Boosting Good Bacteria in the Colon Without Probiotics

Avenanthramides inhibit proliferation of human colon cancer cell lines in vitro.

A high intake of whole grain foods is associated with reduced risk of colon cancer, but the mechanism underlying this protection has yet to be elucidated. Chronic inflammation and associated cyclooxygenase-2 (COX-2) expression in the colon epithelium are causally related to epithelial carcinogenesis, proliferation, and tumor growth. We examined the effect of avenanthramides (Avns), unique polyphenols from oats with anti-inflammatory properties, on COX-2 expression in macrophages, colon cancer cell lines, and on proliferation of human colon cancer cell lines. We found that Avns-enriched extract of oats (AvExO) had no effect on COX-2 expression, but it did inhibit COX enzyme activity and prostaglandin E(2) (PGE(2)) production in lipopolysaccharide-stimulated mouse peritoneal macrophages. Avns (AvExO, Avn-C, and the methylated form of Avn-C (CH3-Avn-C)) significantly inhibited cell proliferation of both COX-2-positive HT29, Caco-2, and LS174T, and COX-2-negative HCT116 human colon cancer cell lines, CH3-Avn-C being the most potent. However, Avns had no effect on COX-2 expression and PGE(2) production in Caco-2 and HT29 colon cancer cells. These results indicate that the inhibitory effect of Avns on colon cancer cell proliferation may be independent of COX-2 expression and PGE(2) production. Thus, Avns might reduce colon cancer risk through inhibition of macrophage PGE(2) production and non-COX-related antiproliferative effects in colon cancer cells. Interestingly, Avns had no effect on cell viability of confluence-induced differentiated Caco-2 cells, which display the characteristics of normal colonic epithelial cells. Our results suggest that the consumption of oats and oat bran may reduce the risk of colon cancer not only because of their high fiber content but also due to Avns, which attenuate proliferation of colonic cancer cells.

Probiotics as prevention and treatment for diarrhea.

PURPOSE OF REVIEW: To critically appraise evidence on probiotic use for prevention and treatment of diarrhea in children and adults. RECENT FINDINGS: Several randomized controlled trials and meta-analyses suggested that probiotics are effective in primary and secondary prevention of gastroenteritis and its treatment. Selected Lactobacillus strains had a modest, although significant effect in primary prevention. Saccharomyces boulardii was effective in antibiotic-associated and in Clostridium difficile diarrhea. There is evidence that it might prevent diarrhea in day-care centers. Lactobacillus rhamnosus GG was associated with reduced diarrheal duration and severity, more evident in case of childhood Rotavirus diarrhea. Similar, although weaker, evidence was obtained with S. boulardii. Both strains are included in evidence-based recommendations for gastroenteritis management in children. Data on other Lactobacillus strains are preliminary. Probiotic efficacy was related to cause, early administration and bacterial load, and their mechanisms were associated with antiinfectious action in the intestine or, indirectly, to modulation of innate and adaptive immunity. SUMMARY: Probiotics have gained a role as adjunctive treatment of infantile gastroenteritis together with rehydration. Their efficacy is less convincing in adults, but promising in antibiotic-associated diarrhea. However, evidence of efficacy is limited to a few strains.

Assessment of psychotropic-like properties of a probiotic formulation (Lactobacillus helveticus R0052 and Bifidobacterium longum R0175) in rats and...

In a previous clinical study, a probiotic formulation (PF) consisting of Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 (PF) decreased stress-induced gastrointestinal discomfort. Emerging evidence of a role for gut microbiota on central nervous system functions therefore suggests that oral intake of probiotics may have beneficial consequences on mood and psychological distress. The aim of the present study was to investigate the anxiolytic-like activity of PF in rats, and its possible effects on anxiety, depression, stress and coping strategies in healthy human volunteers. In the preclinical study, rats were daily administered PF for 2 weeks and subsequently tested in the conditioned defensive burying test, a screening model for anti-anxiety agents. In the clinical trial, volunteers participated in a double-blind, placebo-controlled, randomised parallel group study with PF administered for 30 d and assessed with the Hopkins Symptom Checklist (HSCL-90), the Hospital Anxiety and Depression Scale (HADS), the Perceived Stress Scale, the Coping Checklist (CCL) and 24 h urinary free cortisol (UFC). Daily subchronic administration of PF significantly reduced anxiety-like behaviour in rats (P < 0·05) and alleviated psychological distress in volunteers, as measured particularly by the HSCL-90 scale (global severity index, P < 0·05; somatisation, P < 0·05; depression, P < 0·05; and anger-hostility, P < 0·05), the HADS (HADS global score, P < 0·05; and HADS-anxiety, P < 0·06), and by the CCL (problem solving, P < 0·05) and the UFC level (P < 0·05). L. helveticus R0052 and B. longum R0175 taken in combination display anxiolytic-like activity in rats and beneficial psychological effects in healthy human volunteers.

Dose-response efficacy of a proprietary probiotic formula of Lactobacillus acidophilus CL1285 and Lactobacillus casei LBC80R for antibiotic-associa...

OBJECTIVES: Standard therapies for antibiotic-associated diarrhea (AAD) and Clostridium difficile-associated diarrhea (CDAD) have limited efficacy. Probiotic prophylaxis is a promising alternative for reduction of AAD and CDAD incidence. METHODS: In this single-center, randomized, double-blind, placebo-controlled dose-ranging study, we randomized 255 adult inpatients to one of three groups: two probiotic capsules per day (Pro-2, n=86), one probiotic capsule and one placebo capsule per day (Pro-1, n=85), or two placebo capsules per day (n=84). Each probiotic capsule contained 50 billion c.f.u. of live organisms (Lactobacillus acidophilus CL1285 +Lactobacillus casei LBC80R Bio-K+ CL1285). Probiotic prophylaxis began within 36 h of initial antibiotic administration, continued for 5 days after the last antibiotic dose, and patients were followed for an additional 21 days. RESULTS: Pro-2 (15.5%) had a lower AAD incidence vs. Pro-1 (28.2%). Each probiotic group had a lower AAD incidence vs. placebo (44.1%). In patients who acquired AAD, Pro-2 (2.8 days) and Pro-1 (4.1 days) had shorter symptom duration vs. placebo (6.4 days). Similarly, Pro-2 (1.2%) had a lower CDAD incidence vs. Pro-1 (9.4%). Each treatment group had a lower CDAD incidence vs. placebo (23.8%). Gastrointestinal symptoms were less common in the treatment groups vs. placebo and in Pro-2 vs. Pro-1. CONCLUSIONS: The proprietary probiotic blend used in this study was well tolerated and effective for reducing risk of AAD and, in particular, CDAD in hospitalized patients on antibiotics. A dose-ranging effect was shown with 100 billion c.f.u., yielding superior outcomes and fewer gastrointestinal events compared to 50 billion c.f.u. (ClinicalTrials.gov number NCT00958308).

The impact of meals on a probiotic during transit through a model of the human upper gastrointestinal tract.

Commercial literature on various probiotic products suggests that they can be taken before meals, during meals or after meals or even without meals. This has led to serious confusion for the industry and the consumer. The objective of our study was to examine the impact of the time of administration with respect to mealtime and the impact of the buffering capacity of the food on the survival of probiotic microbes during gastrointestinal transit. We used an in vitro Digestive System (IViDiS) model of the upper gastrointestinal tract to examine the survival of a commercial multi-strain probiotic, ProtecFlor®. This product, in a capsule form, contains four different microbes: two lactobacilli (Lactobacillus helveticus R0052 and Lactobacillus rhamnosus R0011), Bifidobacterium longum R0175 and Saccharomyces cerevisiae boulardii. Enumeration during and after transit of the stomach and duodenal models showed that survival of all the bacteria in the product was best when given with a meal or 30 minutes before a meal (cooked oatmeal with milk). Probiotics given 30 minutes after the meal did not survive in high numbers. Survival in milk with 1% milk fat and oatmeal-milk gruel were significantly better than apple juice or spring water. S. boulardii was not affected by time of meal or the buffering capacity of the meal. The protein content of the meal was probably not as important for the survival of the bacteria as the fat content. We conclude that ideally, non-enteric coated bacterial probiotic products should be taken with or just prior to a meal containing some fats.

The increase in plasma nitrite after a dietary nitrate load is markedly attenuated by an antibacterial mouthwash.

Recent studies surprisingly show that dietary inorganic nitrate, abundant in vegetables, can be metabolized in vivo to form nitrite and then bioactive nitric oxide. A reduction in blood pressure was recently noted in healthy volunteers after dietary supplementation with nitrate; an effect consistent with formation of vasodilatory nitric oxide. Oral bacteria have been suggested to play a role in bioactivation of nitrate by first reducing it to the more reactive anion nitrite. In a cross-over designed study in seven healthy volunteers we examined the effects of a commercially available chlorhexidine-containing antibacterial mouthwash on salivary and plasma levels of nitrite measured after an oral intake of sodium nitrate (10mg/kg dissolved in water). In the control situation the salivary and plasma levels of nitrate and nitrite increased greatly after the nitrate load. Rinsing the mouth with the antibacterial mouthwash prior to the nitrate load had no effect on nitrate accumulation in saliva or plasma but abolished its conversion to nitrite in saliva and markedly attenuated the rise in plasma nitrite. We conclude that the acute increase in plasma nitrite seen after a nitrate load is critically dependent on nitrate reduction in the oral cavity by commensal bacteria. The removal of these bacteria with an antibacterial mouthwash will very likely attenuate the NO-dependent biological effects of dietary nitrate.

Bismuth therapy in gastrointestinal diseases.

Bismuth therapy has shown efficacy against two major gastrointestinal disorders: peptic ulcer disease and diarrhea. In peptic ulcer disease it is as effective as the H2-receptor antagonists, costs considerably less, and offers a lower rate of relapse. When Helicobacter pylori is implicated, bismuth acts as an antimicrobial agent, suppressing the organism but not eliminating it. In recent studies, bismuth compounds have been used with conventional antibiotics, producing elimination of the organism, histological improvement, and amelioration of symptoms for periods longer than one year. Bismuth subsalicylate has shown modest efficacy in treating traveler's diarrhea and acute and chronic diarrhea in children, and it is effective prophylactically for traveler's diarrhea. An epidemic of neurological toxicity was reported in France in the 1970's with prolonged bismuth treatment, usually bismuth subgallate and subnitrate. Such toxicity has been rare with bismuth subsalicylate and colloidal bismuth subcitrate. However, recent studies have demonstrated intestinal absorption of bismuth (about 0.2% of the ingested dose) and sequestration of this heavy metal in multiple tissue sites, even occurring with conventional dosing over a 6-week period. These findings have inspired recommendations that treatment periods with any bismuth-containing compound should last no longer than 6-8 weeks, followed by 8-week bismuth-free intervals.

Nutrition and colonic health: the critical role of the microbiota.

PURPOSE OF REVIEW: To highlight mechanisms whereby diet affects colonic function and disease patterns. RECENT FINDINGS: Topical nutrients are preferentially used by the gut mucosa to maintain structure and function. With the colon, topical nutrients are generated by the colonic microbiota to maintain mucosal health. Most importantly, short chain fatty acids control proliferation and differentiation, thereby reducing colon cancer risk. In patients with massive loss of small intestine, short chain fatty acid production supports survival by releasing up to 1000 kcal energy/day. Human studies show that the microbiota synthesizes a large pool of utilizable folate which may support survival in impoverished populations. Unfortunately, the microbiota may also elaborate toxic products from food residues such as genotoxic hydrogen sulfide by sulfur-reducing bacteria in response to a high-meat diet. The employment of culture-free techniques based on 16S regions of DNA has revealed that our colons harbor over 800 bacterial species and 7000 different strains. Evidence suggests that the diet directly influences the diversity of the microbiota, providing the link between diet, colonic disease, and colon cancer. The microbiota, however, can determine the efficiency of food absorption and risk of obesity. SUMMARY: Our investigations have focused on a small number of bacterial species: characterization of microbiota and its metabolism can be expected to provide the key to colonic health and disease.

High polyphenol, low probiotic diet for weight loss because of intestinal microbiota interaction.

The relative proportion of Bacteroidetes to Firmicutes is decreased in obese people. This imbalance in gut microbiota generates signals controlling the expression of genes by the epithelial intestinal cells. Both dairy and non-dairy probiotics increase body weight, reportedly through Lactobacillus species growth in the gut. On the other hand, daily intake of some fruits and drinks such as three apples or three pears or grapefruit, or green tea, which all are rich in polyphenols, can significantly reduce body weight in obese people. Metabolism of polyphenols by microbiota involves the cleavage of glycosidic linkages. Glycans, which are the product of glycosidic cleavage, are necessary for survival of the intestinal microbiota as a nutrient foundation. There are two pivotal points: (i) Firmicutes possess a disproportionately smaller number of glycan-degrading enzymes than Bacteroidetes, (ii) Firmicutes are more repressed than the Bacteroidetes by phenolic compounds' antimicrobial properties. The Bacteroidetes community prevails following dietary polyphenol intake and its fermentation to phenolic compounds, due to having more glycan-degrading enzymes, so this may thus be a mechanism by which dietary polyphenols exert their weight lowering effect. I suggest that future studies utilize clone libraries and fingerprinting techniques enabling identification of the composition and community structure of the microbiota, and dot blot hybridization or fluorescent in situ hybridization to analyze abundance of particular taxa in obese and individuals. A supplementation with polyphenols with high bioavailability in obese individuals with higher Firmicutes/Bacteroides community ratio phenotype, when associated to a probiotic restricted diet, is proposed for weight loss; this hypothesis could have relevant implication in planning a successful dietary regimen and/or neutraceutical/pharmaceutical preparations for achieving and maintaining a normal body weight in obese individuals, especially including much more use of polyphenol-rich foodstuffs and/or polyphenol-rich syrups, and including low amounts of probiotic-rich foodstuffs like yogurt, soy yogurt, or as probiotic supplements. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Anti-proliferative activity and chemoprotective effects towards DNA oxidative damage of fresh and cooked Brassicaceae.

Epidemiological evidence shows that regular consumption of Brassicaceae is associated with a reduced risk of cancer and heart disease. Cruciferous species are usually processed before eating and the real impact of cooking practices on their bioactive properties is not fully understood. We have evaluated the effect of common cooking practices (boiling, microwaving, and steaming) on the biological activities of broccoli, cauliflower and Brussels sprouts. Anti-proliferative and chemoprotective effects towards DNA oxidative damage of fresh and cooked vegetable extracts were evaluated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium and Comet assays on HT-29 human colon carcinoma cells. The fresh vegetable extracts showed the highest anti-proliferative and antioxidant activities on HT-29 cells (broccoli>cauliflower = Brussels sprouts). No genotoxic activity was detected in any of the samples tested. The cooking methods that were applied influenced the anti-proliferative activity of Brassica extracts but did not alter considerably the antioxidant activity presented by the raw vegetables. Raw, microwaved, boiled (except broccoli) and steamed vegetable extracts, at different concentrations, presented a protective antioxidative action comparable with vitamin C (1 mm). These data provide new insight into the influence of domestic treatment on the quality of food, which could support the recent epidemiological studies suggesting that consumption of cruciferous vegetables, mainly cooked, may be related to a reduced risk of developing cancer.

Faecal urobilinogen levels and pH of stools in population groups with different incidence of cancer of the colon, and their possible role in its aetiology.

Mean faecal urobilinogen levels and the pH of stools were both found to be higher in subjects from a population group at high risk of developing cancer of the colon than in subjects matched for age, sex and socioeconomic status from a low-risk population group. An alkaline reaction of the colon contents seems to have a tumorigenic effect by a direct action on the mucus of the mucous cells. An acidic reaction, on the other hand, appears to be protective. These differences are dependent on the patterns of diet and manner of eating. Proper mastication of food, roughage, cellulose and vegetable fibre, and short-chain fatty acids of milk and fermented milk products in the diet appear to be protective.

Black pepper and its pungent principle-piperine: a review of diverse physiological effects.

Black pepper (Piper nigrum) is one of the most widely used among spices. It is valued for its distinct biting quality attributed to the alkaloid, piperine. Black pepper is used not only in human dietaries but also for a variety of other purposes such as medicinal, as a preservative, and in perfumery. Many physiological effects of black pepper, its extracts, or its major active principle, piperine, have been reported in recent decades. Dietary piperine, by favorably stimulating the digestive enzymes of pancreas, enhances the digestive capacity and significantly reduces the gastrointestinal food transit time. Piperine has been demonstrated in in vitro studies to protect against oxidative damage by inhibiting or quenching free radicals and reactive oxygen species. Black pepper or piperine treatment has also been evidenced to lower lipid peroxidation in vivo and beneficially influence cellular thiol status, antioxidant molecules and antioxidant enzymes in a number of experimental situations of oxidative stress. The most far-reaching attribute of piperine has been its inhibitory influence on enzymatic drug biotransforming reactions in the liver. It strongly inhibits hepatic and intestinal aryl hydrocarbon hydroxylase and UDP-glucuronyl transferase. Piperine has been documented to enhance the bioavailability of a number of therapeutic drugs as well as phytochemicals by this very property. Piperine's bioavailability enhancing property is also partly attributed to increased absorption as a result of its effect on the ultrastructure of intestinal brush border. Although initially there were a few controversial reports regarding its safety as a food additive, such evidence has been questionable, and later studies have established the safety of black pepper or its active principle, piperine, in several animal studies. Piperine, while it is non-genotoxic, has in fact been found to possess anti-mutagenic and anti-tumor influences.

Antagonistic effects of sulfide and butyrate on proliferation of colonic mucosa: a potential role for these agents in the pathogenesis of ulcerativ...

It has been shown that feces of patients with ulcerative colitis uniformly contain sulfate reducing bacteria. Sulfide produced by these bacteria interferes with butyrate-dependent energy metabolism of cultured colonocytes and may be involved in the pathogenesis of ulcerative colitis. Mucosal biopsies from the sigmoid rectum of 10 patients (no caner, polyps, inflammatory bowel disease) were incubated with either NaCl, sodium hydrogen sulfide (1 mmol/L), a combination of both sodium hydrogen sulfide and butyrate (10 mmol/L), or butyrate. Mucosal proliferation was assessed by bromodeoxyuridine labeling of cells in S-phase. Compared to NaCl, sulfide increased the labeling of the entire crypt significantly, by 19% (p < 0.05). This effect was due to an expansion of the proliferative zone to the upper crypt (compartments 3-5), where the increase in proliferation was 54%. Sulfide-induced hyperproliferation was reversed when samples were coincubated with sulfide and butyrate. The study shows that sodium hydrogen sulfide induces mucosal hyperproliferation. Our data support a possible role of sulfide in the pathogenesis of UC and confirm the role of butyrate in the regulation of colonic proliferation and in the treatment of UC.

Suppression of colonic cancer by dietary phytic acid.

Large differences exist between human populations in the frequency of colonic cancer. Epidemiological evidence indicates that these differences are strongly influenced by country of residence, and a negative correlation has been found between the fiber content of the diet and frequency of colonic cancer. This has prompted the hypothesis that high-fiber diets are in some way protective. However, reanalysis of the dietary data provides equally strong support for the hypothesis that the protective element may be phytic acid (inositol hexaphosphate). This heat- and acid-stable substance is present in high concentration in many food items, including cereal grains, nuts, and seeds. Phytic acid forms chelates with various metals and suppresses damaging iron-catalyzed redox reactions. Inasmuch as colonic bacteria have been shown to produce oxygen radicals in appreciable amounts, dietary phytic acid might suppress oxidant damage to intestinal epithelium and neighboring cells. Indeed, rapidly accumulating data from animal models indicate that dietary supplementation with phytic acid may provide substantial protection against experimentally induced colonic cancer. Should further investigations yield additional support for this hypothesis, purposeful amplification of dietary phytic acid content would represent a simple method for reducing the risk of colonic carcinogenesis.

Probiotics for the prevention of pediatric antibiotic-associated diarrhea.

BACKGROUND: Antibiotics alter the microbial balance within the gastrointestinal tract. Probiotics may prevent antibiotic-associated diarrhea (AAD) via restoration of the gut microflora. Antibiotics are prescribed frequently in children and AAD is common in this population. OBJECTIVES: To assess the efficacy and adverse effects of probiotics (any specified strain or dose) for the prevention of antibiotic-associated diarrhea in children. To assess adverse events associated with the use of probiotics when co-administered with antibiotics in children. SEARCH STRATEGY: MEDLINE, EMBASE, CENTRAL, CINAHL , AMED, and the Web of Science (inception to August 2006) were searched along with specialized registers including the Cochrane IBD/FBD Review Group, CISCOM, Chalmers PedCAM Research Register and trial registries from inception to 2005. Letters were sent to authors of included trials, nutra/pharmaceutical companies, and experts in the field requesting additional information on ongoing or unpublished trials. Conference proceedings, dissertation abstracts, and reference lists from included and relevant articles were hand searched. SELECTION CRITERIA: Randomized, parallel, controlled (placebo, active, or no treatment) trials comparing co-administered probiotics with antibiotics for the prevention of diarrhea secondary to antibiotic use in children (0 to 18 years). DATA COLLECTION AND ANALYSIS: Methodological quality assessment and data extraction were conducted independently by two authors (BCJ, AS). Dichotomous data (incidence of diarrhea, adverse events) were combined using pooled relative risks, and continuous data (mean duration of diarrhea, mean daily stool frequency) as weighted mean differences, along with their corresponding 95% confidence intervals. Adverse events were summarized using risk difference. For overall pooled results on the incidence of diarrhea, a priori sensitivity analyses included per protocol versus intention to treat, random versus fixed effects, and methodological quality criterion. Subgroup analysis were conducted on probiotic strain, dose, definition of antibiotic-associated diarrhea, and antibiotic agent. MAIN RESULTS: Ten studies met the inclusion criteria. Trials included treatment with either Lactobacilli spp., Bifidobacterium spp., Streptococcus spp., or Saccharomyces boulardii alone or in combination. Six studies used a single strain probiotic agent and four combined two probiotic strains. The per protocol analysis for 9/10 trials reporting on the incidence of diarrhea show statistically significant results favouring probiotics over active/non active controls (RR 0.49; 95% CI 0.32 to 0.74). However, intention to treat analysis showed non-significant results overall (RR 0.90; 95% CI 0.50 to 1.63). Five of ten trials monitored for adverse events (n = 647); none reported a serious adverse event. AUTHORS' CONCLUSIONS: Probiotics show promise for the prevention of pediatric AAD. While per protocol analysis yields treatment effect estimates that are both statistically and clinically significant, as does analysis of high quality studies, the estimate from the intention to treat analysis was not statistically significant. Future studies should involve probiotic strains and doses with the most promising evidence (e.g., Lactobacillus GG, Lactobacillus sporogenes, Saccharomyces boulardii at 5 to 40 billion colony forming units/day). Research done to date does not permit determination of the effect of age (e.g., infant versus older children) or antibiotic duration (e.g., 5 days versus 10 days). Future trials would benefit from a validated primary outcome measure for antibiotic-associated diarrhea that is sensitive to change and reflects what treatment effect clinicians, parents, and children consider important. The current data are promising, but it is premature to routinely recommend probiotics for the prevention of pediatric AAD.

Therapeutic Roles of Curcumin: Lessons Learned from Clinical Trials

Extensive research over the past half century has shown that curcumin (diferuloylmethane), a component of the golden spice turmeric (Curcuma longa), can modulate multiple cell signaling pathways. Extensive clinical trials over the past quarter century have addressed the pharmacokinetics, safety, and efficacy of this nutraceutical against numerous diseases in humans. Some promising effects have been observed in patients with various pro-inflammatory diseases including cancer, cardiovascular disease, arthritis, uveitis, ulcerative proctitis, Crohn’s disease, ulcerative colitis, irritable bowel disease, tropical pancreatitis, peptic ulcer, gastric ulcer, idiopathic orbital inflammatory pseudotumor, oral lichen planus, gastric inflammation, vitiligo, psoriasis, acute coronary syndrome, atherosclerosis, diabetes, diabetic nephropathy, diabetic microangiopathy, lupus nephritis, renal conditions, acquired immunodeficiency syndrome, β-thalassemia, biliary dyskinesia, Dejerine-Sottas disease, cholecystitis, and chronic bacterial prostatitis. Curcumin has also shown protection against hepatic conditions, chronic arsenic exposure, and alcohol intoxication. Dose-escalating studies have indicated the safety of curcumin at doses as high as 12 g/day over 3 months. Curcumin’s pleiotropic activities emanate from its ability to modulate numerous signaling molecules such as pro-inflammatory cytokines, apoptotic proteins, NF–κB, cyclooxygenase-2, 5-LOX, STAT3, C-reactive protein, prostaglandin E2, prostate-specific antigen, adhesion molecules, phosphorylase kinase, transforming growth factor-β, triglyceride, ET-1, creatinine, HO-1, AST, and ALT in human participants. In clinical trials, curcumin has been used either alone or in combination with other agents. Various formulations of curcumin, including nanoparticles, liposomal encapsulation, emulsions, capsules, tablets, and powder, have been examined. In this review, we discuss in detail the various human diseases in which the effect of curcumin has been investigated.

Effect of meal composition and cooking duration on the fate of sulforaphane following consumption of broccoli by healthy human subjects.

The isothiocyanate, sulforaphane, has been implicated in the cancer-protective effects of brassica vegetables. When broccoli is consumed, sulforaphane is released from hydrolysis of glucoraphanin by plant myrosinase and/or colonic microbiota. The influence of meal composition and broccoli-cooking duration on isothiocyanate uptake was investigated in a designed experiment. Volunteers (n 12) were each offered a meal, with or without beef, together with 150 g lightly cooked broccoli (microwaved 2.0 min) or fully cooked broccoli (microwaved 5.5 min), or a broccoli seed extract. They received 3 g mustard containing pre-formed allyl isothiocyanate (AITC) with each meal. Urinary output of allyl (AMA) and sulforaphane (SFMA) mercapturic acids, the biomarkers of production of AITC and sulforaphane respectively, were measured for 24 h after meal consumption. The estimated yield of sulforaphane in vivo was about 3-fold higher after consumption of lightly cooked broccoli than fully cooked broccoli. Absorption of AITC from mustard was about 1.3-fold higher following consumption of the meat-containing meal compared with the non meat-containing alternative. The meal matrix did not significantly influence the hydrolysis of glucoraphanin and its excretion as SFMA from broccoli. Isothiocyanates may interact with the meal matrix to a greater extent if they are ingested pre-formed rather than after their production from hydrolysis of glucosinolates in vivo. The main influence on the production of isothiocyanates in vivo is the way in which brassica vegetables are cooked, rather than the effect of the meal matrix.

Probiotic effects on cold and influenza-like symptom incidence and duration in children.

OBJECTIVE: Probiotic consumption effects on cold and influenza-like symptom incidence and duration were evaluated in healthy children during the winter season. METHODS: In this double-blind, placebo-controlled study, 326 eligible children (3-5 years of age) were assigned randomly to receive placebo (N = 104), Lactobacillus acidophilus NCFM (N = 110), or L acidophilus NCFM in combination with Bifidobacterium animalis subsp lactis Bi-07 (N = 112). Children were treated twice daily for 6 months. RESULTS: Relative to the placebo group, single and combination probiotics reduced fever incidence by 53.0% (P = .0085) and 72.7% (P = .0009), coughing incidence by 41.4% (P = .027) and 62.1% (P = .005), and rhinorrhea incidence by 28.2% (P = .68) and 58.8% (P = .03), respectively. Fever, coughing, and rhinorrhea duration was decreased significantly, relative to placebo, by 32% (single strain; P = .0023) and 48% (strain combination; P < .001). Antibiotic use incidence was reduced, relative to placebo, by 68.4% (single strain; P = .0002) and 84.2% (strain combination; P < .0001). Subjects receiving probiotic products had significant reductions in days absent from group child care, by 31.8% (single strain; P = .002) and 27.7% (strain combination; P < .001), compared with subjects receiving placebo treatment. CONCLUSION: Daily dietary probiotic supplementation for 6 months was a safe effective way to reduce fever, rhinorrhea, and cough incidence and duration and antibiotic prescription incidence, as well as the number of missed school days attributable to illness, for children 3 to 5 years of age.

Diet, microbiota, and microbial metabolites in colon cancer risk in rural Africans and African Americans

Background: Epidemiologic studies have suggested that most cases of sporadic colon cancer can be attributed to diet. The recognition that colonic microbiota have a major influence on colonic health suggests that they might mediate colonic carcinogenesis. Objective: To examine the hypothesis that the influence of diet on colon cancer risk is mediated by the microbiota through their metabolites, we measured differences in colonic microbes and their metabolites in African Americans with a high risk and in rural native Africans with a low risk of colon cancer. Design: Fresh fecal samples were collected from 12 healthy African Americans aged 50–65 y and from 12 age- and sex-matched native Africans. Microbiomes were analyzed with 16S ribosomal RNA gene pyrosequencing together with quantitative polymerase chain reaction of the major fermentative, butyrate-producing, and bile acid–deconjugating bacteria. Fecal short-chain fatty acids were measured by gas chromatography and bile acids by liquid chromatography–mass spectrometry. Results: Microbial composition was fundamentally different, with a predominance of Prevotella in native Africans (enterotype 2) and of Bacteroides in African Americans (enterotype 1). Total bacteria and major butyrate-producing groups were significantly more abundant in fecal samples from native Africans. Microbial genes encoding for secondary bile acid production were more abundant in African Americans, whereas those encoding for methanogenesis and hydrogen sulfide production were higher in native Africans. Fecal secondary bile acid concentrations were higher in African Americans, whereas short-chain fatty acids were higher in native Africans. Conclusion: Our results support the hypothesis that colon cancer risk is influenced by the balance between microbial production of health-promoting metabolites such as butyrate and potentially carcinogenic metabolites such as secondary bile acids.

Hypothesis: is antibiotic use associated with breast cancer?

The hypothesis that antibiotic use may increase cancer risk was first proposed several decades ago and some research suggests an increased risk of breast cancer among women with conditions likely to require long-term antibiotic use (e.g., acne, recurrent urinary-tract infections, UTI). However, this hypothesis has not been verified and the possible biological mechanisms are not entirely clear. A recent cohort study in Finland reported an increased risk of breast-cancer associated with antibiotic use for UTI. The effect of antibiotics on the ability of intestinal microflora to metabolise phytochemicals from edible plants into compounds that may protect against cancer was proposed as a potential mechanism. We extend this hypothesis by proposing that antibiotic use may be associated with breast-cancer risk through effects on immune and inflammatory factors, such as cytokines, T lymphocytes, prostaglandins, and matrix metalloproteinases, as well as disruption of phytochemical and oestrogen metabolism by intestinal microflora. We suggest that some mechanisms may increase breast-cancer risk, while others may decrease risk, depending on the antibiotic classification.

Treatment of abdominal pain in irritable bowel syndrome.

Functional abdominal pain in the context of irritable bowel syndrome (IBS) is a challenging problem for primary care physicians, gastroenterologists and pain specialists. We review the evidence for the current and future non-pharmacological and pharmacological treatment options targeting the central nervous system and the gastrointestinal tract. Cognitive interventions such as cognitive behavioral therapy and hypnotherapy have demonstrated excellent results in IBS patients, but the limited availability and labor-intensive nature limit their routine use in daily practice. In patients who are refractory to first-line therapy, tricyclic antidepressants (TCA) and selective serotonin reuptake inhibitors are both effective to obtain symptomatic relief, but only TCAs have been shown to improve abdominal pain in meta-analyses. A diet low in fermentable carbohydrates and polyols (FODMAP) seems effective in subgroups of patients to reduce abdominal pain, bloating, and to improve the stool pattern. The evidence for fiber is limited and only isphagula may be somewhat beneficial. The efficacy of probiotics is difficult to interpret since several strains in different quantities have been used across studies. Antispasmodics, including peppermint oil, are still considered the first-line treatment for abdominal pain in IBS. Second-line therapies for diarrhea-predominant IBS include the non-absorbable antibiotic rifaximin and the 5HT3 antagonists alosetron and ramosetron, although the use of the former is restricted because of the rare risk of ischemic colitis. In laxative-resistant, constipation-predominant IBS, the chloride-secretion stimulating drugs lubiprostone and linaclotide, a guanylate cyclase C agonist that also has direct analgesic effects, reduce abdominal pain and improve the stool pattern.

Mechanisms of primary cancer prevention by butyrate and other products formed during gut flora-mediated fermentation of dietary fibre.

Dietary fibres are indigestible food ingredients that reach the colon and are then fermented by colonic bacteria, resulting mainly in the formation of short-chain fatty acids (SCFA) such as acetate, propionate, and butyrate. Those SCFA, especially butyrate, are recognised for their potential to act on secondary chemoprevention by slowing growth and activating apoptosis in colon cancer cells. Additionally, SCFA can also act on primary prevention by activation of different drug metabolising enzymes. This can reduce the burden of carcinogens and, therefore, decrease the number of mutations, reducing cancer risk. Activation of GSTs by butyrate has been studied on mRNA, protein, and enzyme activity level by real-time RT-PCR, cDNA microarrays, Western blotting, or photometrical approaches, respectively. Butyrate had differential effects in colon cells of different stages of cancer development. In HT29 tumour cells, e.g., mRNA GSTA4, GSTP1, GSTM2, and GSTT2 were induced. In LT97 adenoma cells, GSTM3, GSTT2, and MGST3 were induced, whereas GSTA2, GSTT2, and catalase (CAT) were elevated in primary colon cells. Colon cells of different stages of carcinogenesis differed in post-transcriptional regulatory mechanisms because butyrate increased protein levels of different GST isoforms and total GST enzyme activity in HT29 cells, whereas in LT97 cells, GST protein levels and activity were slightly reduced. Because butyrate increased histone acetylation and phosphorylation of ERK in HT29 cells, inhibition of histone deacetylases and the influence on MAPK signalling are possible mechanisms of GST activation by butyrate. Functional consequences of this activation include a reduction of DNA damage caused by carcinogens like hydrogen peroxide or 4-hydroxynonenal (HNE) in butyrate-treated colon cells. Treatment of colon cells with the supernatant from an in vitro fermentation of inulin increased GST activity and decreased HNE-induced DNA damage in HT29 cells. Additional animal and human studies are needed to define the exact role of dietary fibre and butyrate in inducing GST activity and reducing the risk of colon cancer.

Probiotics, prebiotics infant formula use in preterm or low birth weight infants: a systematic review

Background Previous reviews (2005 to 2009) on preterm infants given probiotics or prebiotics with breast milk or mixed feeds focused on prevention of Necrotizing Enterocolitis, sepsis and diarrhea. This review assessed if probiotics, prebiotics led to improved growth and clinical outcomes in formula fed preterm infants. Methods Cochrane methodology was followed using randomized controlled trials (RCTs) which compared preterm formula containing probiotic(s) or prebiotic(s) to conventional preterm formula in preterm infants. The mean difference (MD) and corresponding 95% confidence intervals (CI) were reported for continuous outcomes, risk ratio (RR) and corresponding 95% CI for dichotomous outcomes. Heterogeneity was assessed by visual inspection of forest plots and a chi2 test. An I2 test assessed inconsistencies across studies. I2> 50% represented substantial heterogeneity. Results Four probiotics studies (N=212), 4 prebiotics studies (N=126) were included. Probiotics: There were no significant differences in weight gain (MD 1.96, 95% CI: -2.64 to 6.56, 2 studies, n=34) or in maximal enteral feed (MD 35.20, 95% CI: -7.61 to 78.02, 2 studies, n=34), number of stools per day increased significantly in probiotic group (MD 1.60, 95% CI: 1.20 to 2.00, 1 study, n=20). Prebiotics: Galacto-oligosaccharide / Fructo-oligosaccharide (GOS/FOS) yielded no significant difference in weight gain (MD 0.04, 95% CI: -2.65 to 2.73, 2 studies, n=50), GOS/FOS yielded no significant differences in length gain (MD 0.01, 95% CI: -0.03 to 0.04, 2 studies, n=50). There were no significant differences in head growth (MD −0.01, 95% CI: -0.02 to 0.00, 2 studies, n=76) or age at full enteral feed (MD −0.79, 95% CI: -2.20 to 0.61, 2 studies, n=86). Stool frequency increased significantly in prebiotic group (MD 0.80, 95% CI: 0.48 to 1.1, 2 studies, n=86). GOS/FOS and FOS yielded higher bifidobacteria counts in prebiotics group (MD 2.10, 95% CI: 0.96 to 3.24, n=27) and (MD 0.48, 95% CI: 0.28 to 0.68, n=56). Conclusions There is not enough evidence to state that supplementation with probiotics or prebiotics results in improved growth and clinical outcomes in exclusively formula fed preterm infants.

Diallyl sulfide inhibits PhIP-induced DNA strand breaks in normal human breast epithelial cells.

Heterocyclic amines (HCAs) are formed when meat products such as beef, chicken, pork and fish are cooked at high temperatures. The most abundant HCA found in the human diet is 2-amino-1-methyl-6-phenylimidazo[4,5-b] pyridine (PhIP). PhIP causes mammary carcinomas in female rats and mice, and is associated with an increased risk of developing colon, breast, and prostate cancer in humans. PhIP is metabolized by cytochrome P-450s producing N-OH-PhIP. The N-OH-PhIP can be esterified by phase II enzymes forming an arylnitrenium ion that binds to DNA causing adducts. Furthermore, N-OH-PhIP may be reduced by cytochrome b5 reductase producing superoxide anions and hydroxyl radicals causing DNA strand breaks. Diallyl sulfide (DAS) has been shown to prevent cancer in several animal models, presumably by metabolic modulation. We hypothesize that PhIP produces reactive oxygen species causing DNA strand breaks and that DAS will inhibit the formation of PhIP induced DNA strand breaks. To test this hypothesis we treated normal breast epithelial (MCF-10A) cells with PhIP, DAS and a combination of PhIP and DAS. The detection of lipid peroxides was used as a surrogate for ROS. Lipid peroxides were detected using a PeroxiDetect kit (Sigma). PhIP increased the production of lipid peroxides and DAS decreased the PhIP-induced peroxidation by 47%. To determine if PhIP causes DNA strand breaks in MCF-10A cells, cells were treated for 3, 6, 9, and 24 h with PhIP (100 microM), DAS (100 microM) and a combination of PhIP (100 microM) and DAS (100 microM). DNA strand breaks were evaluated using the Comet assay. PhIP produced DNA strand breaks in a dose- and time-dependent fashion. We have shown that DAS inhibits PhIP-induced DNA strand breaks by inhibiting the production of reactive oxygen species. Therefore, we propose that DAS can prevent PhIP-induced breast cancer.

A randomized, double-blind, placebo-controlled pilot study of a probiotic in emotional symptoms of chronic fatigue syndrome

Chronic fatigue syndrome (CFS) is complex illness of unknown etiology. Among the broad range of symptoms, many patients report disturbances in the emotional realm, the most frequent of which is anxiety. Research shows that patients with CFS and other so-called functional somatic disorders have alterations in the intestinal microbial flora. Emerging studies have suggested that pathogenic and non-pathogenic gut bacteria might influence mood-related symptoms and even behavior in animals and humans. In this pilot study, 39 CFS patients were randomized to receive either 24 billion colony forming units of Lactobacillus casei strain Shirota (LcS) or a placebo daily for two months. Patients provided stool samples and completed the Beck Depression and Beck Anxiety Inventories before and after the intervention. We found a significant rise in both Lactobacillus and Bifidobacteria in those taking the LcS, and there was also a significant decrease in anxiety symptoms among those taking the probiotic vs controls (p = 0.01). These results lend further support to the presence of a gut-brain interface, one that may be mediated by microbes that reside or pass through the intestinal tract.

Intestinal Microbial Metabolism of Phosphatidylcholine and Cardiovascular Risk

BACKGROUND Recent studies in animals have shown a mechanistic link between intestinal microbial metabolism of the choline moiety in dietary phosphatidylcholine (lecithin) and coronary artery disease through the production of a proatherosclerotic metabolite, trimethylamine-N-oxide (TMAO). We investigated the relationship among intestinal microbiota-dependent metabolism of dietary phosphatidylcholine, TMAO levels, and adverse cardiovascular events in humans. METHODS We quantified plasma and urinary levels of TMAO and plasma choline and betaine levels by means of liquid chromatography and online tandem mass spectrometry after a phosphatidylcholine challenge (ingestion of two hard-boiled eggs and deuterium [d9]-labeled phosphatidylcholine) in healthy participants before and after the suppression of intestinal microbiota with oral broad-spectrum antibiotics. We further examined the relationship between fasting plasma levels of TMAO and incident major adverse cardiovascular events (death, myocardial infarction, or stroke) during 3 years of follow-up in 4007 patients undergoing elective coronary angiography. RESULTS Time-dependent increases in levels of both TMAO and its d9 isotopologue, as well as other choline metabolites, were detected after the phosphatidylcholine challenge. Plasma levels of TMAO were markedly suppressed after the administration of antibiotics and then reappeared after withdrawal of antibiotics. Increased plasma levels of TMAO were associated with an increased risk of a major adverse cardiovascular event (hazard ratio for highest vs. lowest TMAO quartile, 2.54; 95% confidence interval, 1.96 to 3.28; P<0.001). An elevated TMAO level predicted an increased risk of major adverse cardiovascular events after adjustment for traditional risk factors (P<0.001), as well as in lower-risk subgroups. CONCLUSIONS The production of TMAO from dietary phosphatidylcholine is dependent on metabolism by the intestinal microbiota. Increased TMAO levels are associated with an increased risk of incident major adverse cardiovascular events. (Funded by the National Institutes of Health and others.)

Determination of urinary lignans and phytoestrogen metabolites, potential antiestrogens and anticarcinogens, in urine of women on various habitual ...

Recently two groups of compounds with diphenolic structure, the lignans and the isoflavonic phytoestrogens, were detected and identified in human urine and other biological fluids. These compounds are of great biological interest because they exhibit both in vitro and in vivo weak estrogenic and sometimes also antiestrogenic activities and many plant lignans have been shown to have anticarcinogenic, antiviral, antifungal and other interesting biological effects. The compounds found in relatively large amounts (10-1000 times more than estrogens) in urine are modified by intestinal bacteria from plant lignans and phytoestrogens, which are present in fiber-rich food such as grain and beans. They bind with low affinity to estrogen receptors and preliminary results suggest that they may induce production of sex hormone binding globulin (SHBG) in the liver and in this way may influence sex hormone metabolism and biological effects. Five compounds, the lignans enterolactone (Enl), enterodiol (End) and the isoflavonic phytoestrogen metabolites daidzein (Da), equol (Eq) and O-desmethylangolensin (O-Dma) were measured in urine by gas chromatography-mass spectrometry (selected ion monitoring) using deuterated internal standards in 5 groups of women (total number 53). The members of three dietary groups (omnivores, lactovegetarians and macrobiotics) were living in Boston and of two groups in Helsinki (omnivores and lactovegetarians). Until now measurements have been carried out in 94 72-h samples. The highest mean excretion of the most abundant compound, enterolactone, was found in the macrobiotic group and the lowest in the omnivoric groups. Total mean 24-h excretion of enterolactone was 17,680 nmol in the macrobiotics, 4,170 nmol in the Boston lactovegetarians, 3,650 nmol in the Helsinki lactovegetarians, 2,460 nmol in the Helsinki omnivores and 2,050 nmol in the Boston omnivores. The other diphenols followed approximately the same pattern. In an earlier study the lowest excretion of enterolactone (1,040 nmol/24 h) was found in a group of postmenopausal apparently healthy breast cancer patients living in Boston. It is concluded that further studies are necessary to elucidate the possible role of these compounds in cancer and other diseases. However, the evidence obtained until now seems to justify the conclusion that these compounds may be among the dietary factors affording protection against hormone-dependent cancers in vegetarians and semivegetarians.

Probiotics function mechanistically as delivery vehicles for neuroactive compounds: Microbial endocrinology in the design and use of probiotics.

I hypothesize here that the ability of probiotics to synthesize neuroactive compounds provides a unifying microbial endocrinology-based mechanism to explain the hitherto incompletely understood action of commensal microbiota that affect the host's gastrointestinal and psychological health. Once ingested, probiotics enter an interactive environment encompassing microbiological, immunological, and neurophysiological components. By utilizing a trans-disciplinary framework known as microbial endocrinology, mechanisms that would otherwise not be considered become apparent since any candidate would need to be shared among all three components. The range of neurochemicals produced by probiotics includes neurochemicals for which receptor-based targets on immune and neuronal elements (intestinal and extra-intestinal) have been well characterized. Production of neurochemicals by probiotics therefore allows for their consideration as delivery vehicles for neuroactive compounds. This unifying microbial endocrinology-based hypothesis, which may facilitate the selection and design of probiotics for clinical use, also highlights the largely unrecognized role of neuroscience in understanding how microbes may influence health. Copyright © 2011 WILEY Periodicals, Inc.

Storage elevates phenolic content and antioxidant activity but suppresses antiproliferative and pro-apoptotic properties of colored-flesh potatoes ...

Colored-flesh potatoes are an excellent source of health-benefiting dietary polyphenols, but are stored for up to 3-6 months before consumption. This study investigated the effect of simulated commercial storage conditions on antioxidant activity (DPPH, ABTS), phenolic content (FCR) and composition (UPLC-MS), and anticancer properties (early, HCT-116 and advanced stage, HT-29 human colon cancer cell lines) of potato bioactive compounds. Extracts from seven potato clones of differing flesh colors (white, yellow, and purple) before and after 90 days of storage were used in this study. The antioxidant activity of all clones increased with storage; however, an increase in total phenolic content was observed only in purple-fleshed clones. Advanced purple-fleshed selection CO97227-2P/PW had greater levels of total phenolics, monomeric anthocyanins, antioxidant activity and a diverse anthocyanin composition as compared with Purple Majesty. Purple-fleshed potatoes were more potent in suppressing proliferation and elevating apoptosis of colon cancer cells compared with white- and yellow-fleshed potatoes. The extracts from both fresh and stored potatoes (10-30 μg/mL) suppressed cancer cell proliferation and elevated apoptosis compared with the solvent control, but these anticancer effects were more pronounced with the fresh potatoes. Storage duration had a strong positive correlation with antioxidant activity and percentage of viable cancer cells and a negative correlation with apoptosis induction. These results suggest that although the antioxidant activity and phenolic content of potatoes were increased with storage, the antiproliferative and pro-apoptotic activities were suppressed. Thus, in the assessment of the effects of farm to fork operations on the health-benefiting properties of plant foods, it is critical to use quantitative analytical techniques in conjunction with in vitro and/or in vivo biological assays.

Multi-targeted prevention of cancer by sulforaphane

Isothiocyanates are found in cruciferous vegetables such as broccoli, Brussels sprouts, cauliflower, and cabbage. Epidemiologic studies suggest that cruciferous vegetable intake may lower overall cancer risk, including colon and prostate cancer. Sulforaphane (SFN) is an isothiocyanate found in cruciferous vegetables and is especially high in broccoli and broccoli sprouts. SFN has proved to be an effective chemoprotective agent in cell culture, carcinogen-induced and genetic animal cancer models, as well as in xenograft models of cancer. Early research focused on the “blocking activity” of SFN via Phase 2 enzyme induction, as well as inhibition of enzymes involved in carcinogen activation, but there has been growing interest in other mechanisms of chemoprotection by SFN. Recent studies suggest that SFN offers protection against tumor development during the “post-initiation” phase and mechanisms for suppression effects of SFN, including cell cycle arrest and apoptosis induction are of particular interest. In humans, a key factor in determining the efficacy of SFN as a chemoprevention agent is gaining an understanding of the metabolism, distribution and bioavailability of SFN and the factors that alter these parameters. This review discusses the established anti-cancer properties of SFN, with an emphasis on the possible chemoprevention mechanisms. The current status of SFN in human clinical trials also is included, with consideration of the chemistry, metabolism, absorption and factors influencing SFN bioavailability.

Carrageenan induces interleukin-8 production through distinct Bcl10 pathway in normal human colonic epithelial cells.

Carrageenan is a high molecular weight sulfated polygalactan used to improve the texture of commercial food products. Its use increased markedly during the last half century, although carrageenan is known to induce inflammation in rheumatological models and in intestinal models of colitis. We performed studies to determine its direct effects on human intestinal cells, including normal human intestinal epithelial cells from colonic surgeries, the normal intestinal epithelial cell line NCM460, and normal rat ileal epithelial cells. Cells were treated with high molecular weight lambda-carrageenan at a concentration of 1 mug/ml for 1-96 h. IL-8, IL-8 promoter activity, total and nuclear NF-kappaB, IkappaBalpha, phospho-IkappaBalpha, and Bcl10 were assessed by immunohistochemistry, Western blot, ELISA, and cDNA microarray. Increased Bcl10, nuclear and cytoplasmic NF-kappaB, IL-8 promoter activation, and IL-8 secretion were detected following carrageenan exposure. Knockdown of Bcl10 by siRNA markedly reduced the increase in IL-8 that followed carrageenan exposure in the NCM460 cells. These results show, for the first time, that exposure of human intestinal epithelial cells to carrageenan triggers a distinct inflammatory pathway via activation of Bcl10 with NF-kappaB activation and upregulation of IL-8 secretion. Since Bcl10 contains a caspase-recruitment domain, similar to that found in NOD2/CARD15 and associated with genetic predisposition to Crohn's disease, the study findings may represent a link between genetic and environmental etiologies of inflammatory bowel disease. Because of the high use of carrageenan as a food additive in the diet, the findings may have clinical significance.

Relevance of protein fermentation to gut health.

It is generally accepted that carbohydrate fermentation results in beneficial effects for the host because of the generation of short chain fatty acids, whereas protein fermentation is considered detrimental for the host's health. Protein fermentation mainly occurs in the distal colon, when carbohydrates get depleted and results in the production of potentially toxic metabolites such as ammonia, amines, phenols and sulfides. However, the effectivity of these metabolites has been established mainly in in vitro studies. In addition, some important bowel diseases such as colorectal cancer (CRC) and ulcerative colitis appear most often in the distal colon, which is the primary site of protein fermentation. Finally, epidemiological studies revealed that diets rich in meat are associated with the prevalence of CRC, as is the case in Western society. Importantly, meat intake not only increases fermentation of proteins but also induces increased intake of fat, heme and heterocyclic amines, which may also play a role in the development of CRC. Despite these indications, the relationship between gut health and protein fermentation has not been thoroughly investigated. In this review, the existing evidence about the potential toxicity of protein fermentation from in vitro animal and human studies will be summarized. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The effect of dietary factors on nitrosoproline levels in human urine.

The effect of dietary components on the levels of nitrosoproline ( NPRO ) excreted over a 24 h period in the urine was examined in volunteers ingesting known amounts of various food products. The ingestion of nitrite-preserved meats (85-170 g per meal), including canned, rolled or Yunnan ham, cured pork, luncheon meat, and various Chinese and European-style sausages, led to urinary NPRO excretion levels ranging from 2.5 to 78.5 micrograms/24 h, whereas the consumption of non-preserved meat and fish products, including chicken, herring, salmon, shrimp, ground beef (hamburger), pork chops and beef liver, led to relatively low NPRO excretion levels, ranging from 0.0 to 0.8 micrograms/24 h. The urinary NPRO levels of 22 vegetarians and 14 lacto-vegetarians averaged 0.8 and 1.4 micrograms/24 h, respectively. A change from a nitrite-preserved meat diet to a vegetarian diet was accompanied by an approximately six-fold reduction in urinary NPRO levels; however, these remained above control levels for at least 3 days following the dietary change. The relatively high NPRO levels following the ingestion of nitrite-preserved meats could not be reduced by nitrite-trapping chemicals, including ascorbic acid, ferulic acid, caffeic acid, or phenolic-containing mixtures such as coffee and tea, which were effective in suppressing endogenous NPRO formation following the intake of nitrate and proline. The high urinary NPRO levels after ingestion of preserved meat products appear to be due to the consumption of preformed NPRO . An understanding of the relative contribution of preformed and endogenously formed nitrosamines appears to be essential when designing dietary intervention programmes.

Curcumin-induced apoptosis of human colon cancer colo 205 cells through the production of ROS, Ca2+ and the activation of caspase-3.

Curcumin (diferuloylmethane), the yellow pigment in turmeric (Curcuma longa), is known to inhibit proliferation of cancer cells by arresting them at various phases of the cell cycle and to induce apoptosis in tumor cells. Curcumin-induced apoptosis mainly involves the activation of caspase-3 and mitochondria-mediated pathway in various cancer cells of different tissue origin. In the present study, the induction of apoptosis and cytotoxicity by curcumin in colon cancer colo 205 cells was investigated by using flow cytometry. The results demonstrated that curcumin induced cytotoxicity and apoptosis dose- and time-depedently. Curcumin induced the production of reactive oxygen species (ROS) and Ca+2, decreased the levels of mitochondria membrane potential and induced caspase-3 activity. Curcumin also promoted the expression of Bax, cytochrome C, p53 and p21 but inhibited the expression of Bcl-2. These observations suggest that curcumin may have a possible therapeutic potential in colon cancer patients.

Recent Perspectives on the Relations between Fecal Mutagenicity, Genotoxicity, and Diet

DNA damage is an essential component of the genesis of colonic cancer. Gut microbial products and food components are thought to be principally responsible for the damage that initiates disease progression. Modified Ames tests and Comet assays have been developed for measuring mutagenicity and genotoxicity. Their relevance to oncogenesis remains to be confirmed, as does the relative importance of different mutagenic and genotoxic compounds present in fecal water and the bacteria involved in their metabolism. Dietary intervention studies provide clues to the likely risks of oncogenesis. High-protein diets lead to increases in N-nitroso compounds in fecal water and greater DNA damage as measured by the Comet assay, for example. Other dietary interventions, such as non-digestible carbohydrates and probiotics, may lead to lower fecal genotoxicity. In order to make recommendations to the general public, we must develop a better understanding of how genotoxic compounds are formed in the colon, how accurate the Ames and Comet assays are, and how diet affects genotoxicity.

The effect of inositol hexaphosphate on the expression of selected metalloproteinases and their tissue inhibitors in IL-1β-stimulated colon cancer cells

Introduction Matrix metalloproteinases (MMPs) have repeatedly been shown to play a very active role in extracellular matrix degradation associated with tumor invasion and metastasis. Tissue inhibitors of MMPs (TIMPs) are well-known for their ability to inhibit MMP activity thereby inhibiting malignant progression. Inositol hexaphosphate (IP6 phytic acid) has been recognized to have both preventive and therapeutic effects against various cancers including that of colon. In in vitro studies, IP6 has been demonstrated to inhibit cancer cell adhesion and migration. In the present study, the effect of IP6 on the expression of MMP and TIMP genes was evaluated in unstimulated and IL-1β-stimulated colon cancer cell line Caco-2. Materials and methods Real-time QRT-PCR was used to validate the transcription level of selected MMP and TIMP genes in Caco-2 cells after treatment with 1 ng/ml of IL-1β, 2.5 mM of IP6, and both for 6, 12, and 24 h. Results Stimulation of cells with IL-1β only resulted in an overexpression of MMP and their TIMP mRNAs. A significant decrease in MMP-13, MMP-3, MMP-2, and TIMP-1 basal expression was achieved by IP6. IP6 was also an efficient downregulator of MMP-1, MMP-9, and TIMP-2 genes transcription stimulated by IL-1β in 6 h lasting culture. After 12 h, IL-1β-induced MMP-2 mRNA expression was significantly reduced by IP6. Conclusion Proinflammatory cytokine IL-1β upregulates MMP and TIMP mRNAs expression in colon cancer epithelial cells Caco-2. IP6 (2.5 mM) influences constitutive expression of both MMP and TIMP genes and downregulates IL-1β stimulated transcription of some of these genes. IP6 exerts its anti-metastatic activity through modulation of MMP and TIMP genes expression to prevent cancer cell migration and invasion.

Defecation frequency and timing, and stool form in the general population: a prospective study.

Because the range of bowel habits and stool types in the community is unknown we questioned 838 men and 1059 women, comprising 72.2% of a random stratified sample of the East Bristol population. Most of them kept records of three consecutive defecations, including stool form on a validated six point scale ranging from hard, round lumps to mushy. Questionnaire responses agreed moderately well with recorded data. Although the most common bowel habit was once daily this was a minority practice in both sexes; a regular 24 hour cycle was apparent in only 40% of men and 33% of women. Another 7% of men and 4% of women seemed to have a regular twice or thrice daily bowel habit. Thus most people had irregular bowels. A third of women defecated less often than daily and 1% once a week or less. Stools at the constipated end of the scale were passed more often by women than men. In women of child bearing age bowel habit and the spectrum of stool types were shifted towards constipation and irregularity compared with older women and three cases of severe slow transit constipation were discovered in young women. Otherwise age had little effect on bowel habit or stool type. Normal stool types, defined as those least likely to evoke symptoms, accounted for only 56% of all stools in women and 61% in men. Most defecations occurred in the early morning and earlier in men than in women. We conclude that conventionally normal bowel function is enjoyed by less than half the population and that, in this aspect of human physiology, younger women are especially disadvantaged.

The response of the colon to eating.

Much evidence indicates that there is an increased motor activity in the colon from eating in several species of animals. Though some of this effect may be cephalic in origin, the greater part of the response results from the arrival of food in the stomach and proximal intestine. Chemoreceptor stimulation appears to be more important than mechanoreceptor stimulation in bringing about this effect. The means by which this effect comes about could be either hormonal or neural. Several polypeptide hormones released from the proximal gut by eating are candidates. Neural pathways through both parasympathetic and sympathetic systems could be responsible. The exact nature of the change in colonic motility that is produced is unknown. It could involve changes in the pacemakers for colonic contractions (the electrical slow waves of the colon and the migrating spike burst of the colon), changes in the excitability of the colonic musculature or changes in colonic mucosal function.

High colonic pH promotes colorectal cancer.

Considerable evidence suggests that the carcinogens or co-carcinogens responsible for the development of colorectal cancer are either bacterially degraded bile acids or cholesterol. It is proposed that a high colonic pH promotes co-carcinogen formation from these substances and that acidification of the colon either by dietary fibre (following its bacterial digestion to short-chain fatty acids) or milk (in lactose-intolerant individuals) may prevent this process.

Antifungal mechanisms supporting boric acid therapy of Candida vaginitis.

BACKGROUND: Boric acid is a commonly cited treatment for recurrent and resistant yeast vaginitis, but data about the extent and mechanism of its antifungal activity are lacking. OBJECTIVES: The aim of this study was to use in vitro methods to understand the spectrum and mechanism of boric acid as a potential treatment for vaginal infection. METHODS: Yeast and bacterial isolates were tested by agar dilution to determine the intrinsic antimicrobial activity of boric acid. Established microbial physiology methods illuminated the mechanism of the action of boric acid against Candida albicans. RESULTS: C. albicans strains (including fluconazole-resistant strains) were inhibited at concentrations attainable intravaginally; as were bacteria. Broth dilution MICs were between 1563 and 6250 mg/L and boric acid proved fungistatic (also reflected by a decrease in CO(2) generation); prolonged culture at 50,000 mg/L was fungicidal. Several organic acids in yeast nitrogen broth yielded a lower pH than equimolar boric acid and sodium borate but were less inhibitory. Cold or anaerobic incubation protected yeast at high boric acid concentrations. Cells maintained integrity for 6 h in boric acid at 37 degrees C, but after 24 h modest intrusion of propidium iodide occurred; loss of plate count viability preceded uptake of vital stain. Growth at sub-MIC concentrations of boric acid decreased cellular ergosterol. The drug efflux pump CDR1 did not protect Candida as CDR1 expression was abrogated by boric acid. Boric acid interfered with the development of biofilm and hyphal transformation. CONCLUSIONS: Boric acid is fungistatic to fungicidal depending on concentration and temperature. Inhibition of oxidative metabolism appears to be a key antifungal mechanism, but inhibition of virulence probably contributes to therapeutic efficacy in vivo.

Curcumin, an active component of turmeric in the prevention and treatment of ulcerative colitis: preclinical and clinical observations.

Inflammatory bowel disease (IBD) comprising of ulcerative colitis (UC) and Crohn's disease (CD) is a major ailment affecting the small and large bowel. In clinics, IBD is treated using 5-amninosalicylates, antibiotics, the steroids and immunomodulators. Unfortunately, the long term usages of these agents are associated with undue side effects and compromise the therapeutic advantage. Accordingly, there is a need for novel agents that are effective, acceptable and non toxic to humans. Preclinical studies in experimental animals have shown that curcumin, an active principle of the Indian spice turmeric (Curcuma longa Linn) is effective in preventing or ameliorating UC and inflammation. Over the last few decades there has been increasing interest in the possible role of curcumin in IBD and several studies with various experimental models of IBD have shown it to be effective in mediating the inhibitory effects by scavenging free radicals, increasing antioxidants, influencing multiple signaling pathways, especially the kinases (MAPK, ERK), inhibiting myeloperoxidase, COX-1, COX-2, LOX, TNF-α, IFN-γ, iNOS; inhibiting the transcription factor NF-κB. Clinical studies have also shown that co-administration of curcumin with conventional drugs was effective, to be well-tolerated and treated as a safe medication for maintaining remission, to prevent relapse and improve clinical activity index. Large randomized controlled clinical investigations are required to fully understand the potential of oral curcumin for treating IBD.

Diet and cell growth modulation by ammonia.

Fiber is not digested by endogenous enzymes but is fermented by microbes principally in the large intestine. With fermentable energy available, microbes synthesize protein by using ammonia released by their enzymes from urea and other nitrogenous substances in ingesta and intestinal secretions. Fibber fermentation also yields fatty acids that lower the concentration of free ammonia by lowering pH. Fiber increases bulk and water of intestinal contents, shortens transit time, and decreases the concentration of toxic substances in contact with the intestinal mucosa. These processes decrease duration and intensity of exposure of the intestinal mucosa to free ammonia, the form of nitrogen that is most toxic and most readily absorbed by cells. At concentrations found in the lower bowel on usual Western diets, ammonia destroys cells, alters nucleic acid synthesis, increases intestinal mucosal cell mass, increases virus infections, favors growth of cancerous cells over noncancerous cells in tissue culture, and increases virus infections. Ammonia in the bowel increases as protein intake increases. The attributes of ammonia and the epidemiological evidence comparing populations that maintain low intakes of unrefined carbohydrate with those that consume high intakes of protein, fat, and refined carbohydrates implicate ammonia in carcinogenesis and other disease processes.

Red meat and colon cancer: should we become vegetarians, or can we make meat safer?

The effect of meat consumption on cancer risk is a controversial issue. However, recent meta-analyses show that high consumers of cured meats and red meat are at increased risk of colorectal cancer. This increase is significant but modest (20-30%). Current WCRF-AICR recommendations are to eat no more than 500 g per week of red meat, and to avoid processed meat. Moreover, our studies show that beef meat and cured pork meat promote colon carcinogenesis in rats. The major promoter in meat is heme iron, via N-nitrosation or fat peroxidation. Dietary additives can suppress the toxic effects of heme iron. For instance, promotion of colon carcinogenesis in rats by cooked, nitrite-treated and oxidized high-heme cured meat was suppressed by dietary calcium and by α-tocopherol, and a study in volunteers supported these protective effects in humans. These additives, and others still under study, could provide an acceptable way to prevent colorectal cancer. Copyright © 2011 Elsevier B.V. All rights reserved.

Gut inflammation in chronic fatigue syndrome

Chronic fatigue syndrome (CFS) is a debilitating disease characterized by unexplained disabling fatigue and a combination of accompanying symptoms the pathology of which is incompletely understood. Many CFS patients complain of gut dysfunction. In fact, patients with CFS are more likely to report a previous diagnosis of irritable bowel syndrome (IBS), a common functional disorder of the gut, and experience IBS-related symptoms. Recently, evidence for interactions between the intestinal microbiota, mucosal barrier function, and the immune system have been shown to play a role in the disorder's pathogenesis. Studies examining the microecology of the gastrointestinal (GI) tract have identified specific microorganisms whose presence appears related to disease; in CFS, a role for altered intestinal microbiota in the pathogenesis of the disease has recently been suggested. Mucosal barrier dysfunction promoting bacterial translocation has also been observed. Finally, an altered mucosal immune system has been associated with the disease. In this article, we discuss the interplay between these factors in CFS and how they could play a significant role in GI dysfunction by modulating the activity of the enteric nervous system, the intrinsic innervation of the gut. If an altered intestinal microbiota, mucosal barrier dysfunction, and aberrant intestinal immunity contribute to the pathogenesis of CFS, therapeutic efforts to modify gut microbiota could be a means to modulate the development and/or progression of this disorder. For example, the administration of probiotics could alter the gut microbiota, improve mucosal barrier function, decrease pro-inflammatory cytokines, and have the potential to positively influence mood in patients where both emotional symptoms and inflammatory immune signals are elevated. Probiotics also have the potential to improve gut motility, which is dysfunctional in many CFS patients.

Anti-cancer properties of phenolics from apple waste on colon carcinogenesis in vitro.

Colorectal cancer is one of the most common cancers in Western countries. The World Health Organisation identifies diet as a critical risk factor in the development and progression of this disease and the protective role of high levels of fruit and vegetable consumption. Several studies have shown that apples contain several phenolic compounds that are potent anti-oxidants in humans. However, little is known about other beneficial properties of apple phenolics in cancer. We have used the HT29, HT115 and CaCo-2 cell lines as in vitro models to examine the effect of apple phenolics (0.01-0.1% apple extract) on key stages of colorectal carcinogenesis, namely; DNA damage (Comet assay), colonic barrier function (TER assay), cell cycle progression (DNA content assay) and invasion (Matrigel assay). Our results indicate that a crude extract of apple phenolics can protect against DNA damage, improve barrier function and inhibit invasion (p<0.05). The anti-invasive effects of the extract were enhanced with twenty-four hour pretreatment of cells (p<0.05). We have shown that a crude apple extract from waste, rich in phenolic compounds, beneficially influences key stages of carcinogenesis in colon cells in vitro.

Human gut microbiota and its relationship to health and disease.

Probiotics are live microorganisms that confer a health benefit on the host when administered in appropriate amounts. Over 700 randomized, controlled, human studies have been conducted with probiotics thus far, with the results providing strong support for the use of probiotics in the clinical prevention or treatment of gastrointestinal tract disorders and metabolic syndrome. The present review is based on webinar presentations that were developed by the American Gastroenterological Association (AGA) in partnership with the International Scientific Association for Probiotics and Prebiotics (ISAPP) and the North American branch of the International Life Sciences Institute (ILSI North America). The presentations provided gastroenterologists and researchers with fundamental and current scientific information on the influence of gut microbiota on human health and disease, as well as clinical intervention strategies and practical guidelines for the use of probiotics and prebiotics. © 2011 International Life Sciences Institute.

Effect of diet on serum albumin and hemoglobin adducts of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in humans.

2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is the most abundant heterocyclic amine formed in meat and fish during cooking and can be used as a model compound for this class of chemicals possibly involved in human carcinogenesis. Knowing the exposure to heterocyclic amines is important for establishing their role in human diseases. Serum albumin (SA) and globin (Gb) adducts were first tested as biomarkers of exposure to PhIP in male Fischer 344 rats given oral doses of 0.1, 0.5, 1 and 10 mg/kg. Blood samples were collected 24 hr after treatment and PhIP released from SA and Gb after acidic hydrolysis was analyzed by gas chromatography-mass spectrometry or liquid chromatography-tandem mass spectrometry. PhIP-SA and Gb adducts increased linearly with the dose. Studies on 35 volunteers with different dietary habits exhibited that diet was a major determinant in the formation of both adducts. PhIP-SA adducts were significantly higher in meat consumers than in vegetarians (6.7 +/- 1.6 and 0.7 +/- 0.3 fmol/mg SA; respectively, mean +/- SE; p = 0.04, Mann-Whitney U test). The Gb adduct pattern was quantitatively lower but paralleled SA (3 +/- 0.8 in meat consumers and 0.3 +/- 0.1 in vegetarians). PhIP-SA adducts were no different in smokers and in non-smokers. The results show for the first time that PhIP-blood protein adducts are present in humans not given the synthetic compound. Both biomarkers appear to be suitable for assessing dietary exposure and internal PhIP dose and may be promising tools for studying the role of heterocyclic amines in the etiology of colon cancer and other diseases. Copyright 2000 Wiley-Liss, Inc.

Dietary roles of non-starch polysaccharides in human nutrition: a review.

Nonstarch polysaccharides (NSPs) occur naturally in many foods. The physiochemical and biological properties of these compounds correspond to dietary fiber. Nonstarch polysaccharides show various physiological effects in the small and large intestine and therefore have important health implications for humans. The remarkable properties of dietary NSPs are water dispersibility, viscosity effect, bulk, and fermentibility into short chain fatty acids (SCFAs). These features may lead to diminished risk of serious diet related diseases which are major problems in Western countries and are emerging in developing countries with greater affluence. These conditions include coronary heart disease, colo-rectal cancer, inflammatory bowel disease, breast cancer, tumor formation, mineral related abnormalities, and disordered laxation. Insoluble NSPs (cellulose and hemicellulose) are effective laxatives whereas soluble NSPs (especially mixed-link β-glucans) lower plasma cholesterol levels and help to normalize blood glucose and insulin levels, making these kinds of polysaccharides a part of dietary plans to treat cardiovascular diseases and Type 2 diabetes. Moreover, a major proportion of dietary NSPs escapes the small intestine nearly intact, and is fermented into SCFAs by commensal microflora present in the colon and cecum and promotes normal laxation. Short chain fatty acids have a number of health promoting effects and are particularly effective in promoting large bowel function. Certain NSPs through their fermented products may promote the growth of specific beneficial colonic bacteria which offer a prebiotic effect. Various modes of action of NSPs as therapeutic agent have been proposed in the present review. In addition, NSPs based films and coatings for packaging and wrapping are of commercial interest because they are compatible with several types of food products. However, much of the physiological and nutritional impact of NSPs and the mechanism involved is not fully understood and even the recommendation on the dose of different dietary NSPs intake among different age groups needs to be studied.

Rapid Detection of Extended-Spectrum-β-Lactamase-Producing Enterobacteriaceae

Enterobacterial strains producing clavulanic-acid-inhibited extended-spectrum β-lactamases (ESBLs) are increasingly reported worldwide. Conventional detection of ESBL production remains time-consuming (24 to 48 h). Therefore, the ESBL NDP (Nordmann/Dortet/Poirel) test was developed for a rapid identification of ESBLs in Enterobacteriaceae. This biochemical test was based on the in vitro detection of a cephalosporin (cefotaxime) hydrolysis that is inhibited by tazobactam addition. The ESBL activity was evidenced by a color change (red to yellow) of a pH indicator (red phenol) due to carboxyl-acid formation resulting from cefotaxime hydrolysis that was reversed by addition of tazobactam (positive test). The ESBL NDP test was applied to cultured strains (215 ESBL producers and 40 ESBL nonproducers). Its sensitivity and specificity were 92.6% and 100%, respectively. Its sensitivity (100%) was excellent for detection of CTX-M producers. A few ESBL producers (n = 16) that remained susceptible to cefotaxime were not detected. The test was also evaluated on spiked blood cultures and showed excellent sensitivity and specificity (100% for both). The test was rapid (less than 1 h) and cost-effective. It can be implemented in any health care facility and is well adapted for infection control purposes in particular.

Novel probiotic candidates for humans isolated from raw fruits and vegetables.

This study was aimed at determining the probiotic potential of a large number of autochthonous lactic acid bacteria isolated from fruit and vegetables. Survival under simulated gastric and intestinal conditions showed that 35% of the strains, mainly belonging to the species Lactobacillus plantarum maintained high cell densities. Selected strains did not affect the immune-mediation by Caco-2 cells. All strains stimulated all 27 immune-mediators by peripheral blood mononuclear cells (PBMC). A significant (P<0.05; P<0.01) increase of the major part of cytokines and growth factors was found. A few chemokines were stimulated. Immune-mediators with pro-inflammatory activity (IL-17, EOTAXIN and IFNγ) were significantly (P<0.01) stimulated by all strains, followed by IL-1b>IP-10>IL-6>MIP1α. Stimulation of IL-12, IL-2 and IL-7 was strain dependent. Only a few strains increased the synthesis of cytokines with anti-inflammatory activity. Six L. plantarum strains were further selected. Four were defined as the strongly adhesive strains (more than 40 bacteria adhering to one Caco-2 cell), and 2 as the adhesive strains (5-40 bacteria adhering to one Caco-2 cell). Five strains grew and acidified chemically defined medium with fructo-oligosaccharides (FOS) as the only carbon source. End-products of FOS fermentation were found. All strains inhibited enterohemorragic Escherichia coli K12 and Bacillus megaterium F6 isolated from human sources. The results of this study showed that some autochthonous lactic acid bacteria from raw fruit and vegetables have functional features to be considered as novel probiotic candidates. Copyright © 2012 Elsevier Ltd. All rights reserved.

Curcumin, demethoxycurcumin and bisdemethoxycurcumin differentially inhibit cancer cell invasion through the down-regulation of MMPs and uPA.

Curcumin (Cur), a component of turmeric (Curcuma longa), has been reported to exhibit antimetastatic activities, but the mechanisms remain unclear. Other curcuminoids present in turmeric, demethoxycurcumin (DMC) and bisdemethoxycurcumin (BDMC) have not been investigated whether they exhibit antimetastatic activity to the same extent as curcumin. The regulation of matrix metalloproteinases (MMPs) and urokinase plasminogen activator (uPA) play important role in cancer cell invasion by cleavage of extracellular matrix (ECM). In this line, we comparatively examined the influence of Cur, DMC and BDMC on the expressions of uPA, MMP-2, MMP-9, membrane Type 1 MMP (MT1-MMP), tissue inhibitor of metalloproteinases (TIMP-2), and in vitro invasiveness of human fibrosarcoma cells. The results indicate that the differential potency for inhibition of cancer cell invasion was BDMC> or =DMC>Cur, whereas the cell migration was not affected. Zymography analysis exhibited that curcumin, DMC and BDMC significantly decreased uPA, active-MMP-2 and MMP-9 but not pro-MMP-2 secretion from the cells in a dose-dependent manner, in which BDMC and DMC show higher potency than curcumin. The suppression of active MMP-2 level correlated with inhibition of MT1-MMP and TIMP-2 protein levels involved in pro-MMP-2 activation. Importantly, BDMC and DMC at 10 microM reduced MT1-MMP and TIMP-2 protein expression, but curcumin slightly reduced only MT1-MMP but not TIMP-2. In addition, three forms of curcuminoids significantly inhibited collagenase, MMP-2, and MMP-9 but not uPA activity. In summary, these data demonstrated that DMC and BDMC show higher antimetastasis potency than curcumin by the differentially down-regulation of ECM degradation enzymes.

Diverse effects of a low dose supplement of lipidated curcumin in healthy middle aged people

Background Curcumin extracts of turmeric are proposed to produce health benefits. To date, human intervention studies have focused mainly on people with existing health problems given high doses of poorly absorbed curcumin. The purpose of the current study was to check whether in healthy people, a low dose of a lipidated curcumin extract could alter wellness-related measures. Methods The present study was conducted in healthy middle aged people (40–60 years old) with a low dose of curcumin (80 mg/day) in a lipidated form expected to have good absorption. Subjects were given either curcumin (N = 19) or placebo (N = 19) for 4 wk. Blood and saliva samples were taken before and after the 4 weeks and analyzed for a variety of blood and saliva measures relevant to health promotion. Results Curcumin, but not placebo, produced the following statistically significant changes: lowering of plasma triglyceride values, lowering of salivary amylase levels, raising of salivary radical scavenging capacities, raising of plasma catalase activities, lowering of plasma beta amyloid protein concentrations, lowering of plasma sICAM readings, increased plasma myeloperoxidase without increased c-reactive protein levels, increased plasma nitric oxide, and decreased plasma alanine amino transferase activities. Conclusion Collectively, these results demonstrate that a low dose of a curcumin-lipid preparation can produce a variety of potentially health promoting effects in healthy middle aged people.

Gut microbiota composition is associated with body weight, weight gain and biochemical parameters in pregnant women.

Obesity is associated with complications during pregnancy and increased health risks in the newborn. The objective of the present study was to establish possible relationships between gut microbiota, body weight, weight gain and biochemical parameters in pregnant women. Fifty pregnant women were classified according to their BMI in normal-weight (n 34) and overweight (n 16) groups. Gut microbiota composition was analysed by quantitative real-time PCR in faeces and biochemical parameters in plasma at 24 weeks of pregnancy. Reduced numbers of Bifidobacterium and Bacteroides and increased numbers of Staphylococcus, Enterobacteriaceae and Escherichia coli were detected in overweight compared with normal-weight pregnant women. E. coli numbers were higher in women with excessive weight gain than in women with normal weight gain during pregnancy, while Bifidobacterium and Akkermansia muciniphila showed an opposite trend. In the whole population, increased total bacteria and Staphylococcus numbers were related to increased plasma cholesterol levels. Increased Bacteroides numbers were related to increased HDL-cholesterol and folic acid levels, and reduced TAG levels. Increased Bifidobacterium numbers were related to increased folic acid levels. Increased Enterobacteriaceae and E. coli numbers were related to increased ferritin and reduced transferrin, while Bifidobacterium levels showed the opposite trend. Therefore, gut microbiota composition is related to body weight, weight gain and metabolic biomarkers during pregnancy, which might be of relevance to the management of the health of women and infants.

Microbial ecology: human gut microbes associated with obesity.

Two groups of beneficial bacteria are dominant in the human gut, the Bacteroidetes and the Firmicutes. Here we show that the relative proportion of Bacteroidetes is decreased in obese people by comparison with lean people, and that this proportion increases with weight loss on two types of low-calorie diet. Our findings indicate that obesity has a microbial component, which might have potential therapeutic implications.

Human gut microbiota: does diet matter?

The human oro-gastrointestinal (GI) tract is a complex system, consisting of oral cavity, pharynx, oesophagus, stomach, small intestine, large intestine, rectum and anus, which all together with the accessory digestive organs constitute the digestive system. The function of the digestive system is to break down dietary constituents into small molecules and then absorb these for subsequent distribution throughout the body. Besides digestion and carbohydrate metabolism, the indigenous microbiota has an important influence on host physiological, nutritional and immunological processes, and commensal bacteria are able to modulate the expression of host genes that regulate diverse and fundamental physiological functions. The main external factors that can affect the composition of the microbial community in generally healthy adults include major dietary changes and antibiotic therapy. Changes in some selected bacterial groups have been observed due to controlled changes to the normal diet e.g. high-protein diet, high-fat diet, prebiotics, probiotics and polyphenols. More specifically, changes in the type and quantity of non-digestible carbohydrates in the human diet influence both the metabolic products formed in the lower regions of the GI tract and the bacterial populations detected in faeces. The interactions between dietary factors, gut microbiota and host metabolism are increasingly demonstrated to be important for maintaining homeostasis and health. Therefore the aim of this review is to summarise the effect of diet, and especially dietary interventions, on the human gut microbiota. Furthermore, the most important confounding factors (methodologies used and intrinsic human factors) in relation to gut microbiota analyses are elucidated.

Consumption of cherries lowers plasma urate in healthy women.

To assess the physiologic effects of cherry consumption, we measured plasma urate, antioxidant and inflammatory markers in 10 healthy women who consumed Bing sweet cherries. The women, age 22-40 y, consumed two servings (280 g) of cherries after an overnight fast. Blood and urine samples were taken before the cherry dose, and at 1.5, 3 and 5 h postdose. Plasma urate decreased 5 h postdose, mean +/- SEM = 183 +/- 15 micro mol/L compared with predose baseline of 214 +/- 13 micro mol/L (P < 0.05). Urinary urate increased postdose, with peak excretion of 350 +/- 33 micro mol/mmol creatinine 3 h postdose compared with 202 +/- 13 at baseline (P < 0.01). Plasma C-reactive protein (CRP) and nitric oxide (NO) concentrations had decreased marginally 3 h postdose (P < 0.1), whereas plasma albumin and tumor necrosis factor-alpha were unchanged. The vitamin C content of the cherries was solely as dehydroascorbic acid, but postdose increases in plasma ascorbic acid indicated that dehydroascorbic acid in fruits is bioavailable as vitamin C. The decrease in plasma urate after cherry consumption supports the reputed anti-gout efficacy of cherries. The trend toward decreased inflammatory indices (CRP and NO) adds to the in vitro evidence that compounds in cherries may inhibit inflammatory pathways.

Immunity: plants as effective mediators.

In the domain of nutrition, exploring the diet-health linkages is major area of research. The outcomes of such interventions led to widespread acceptance of functional and nutraceutical foods; however, augmenting immunity is a major concern of dietary regimens. Indeed, the immune system is incredible arrangement of specific organs and cells that enabled humans to carry out defense against undesired responses. Its proper functionality is essential to maintain the body homeostasis. Array of plants and their components hold immunomodulating properties. Their possible inclusion in diets could explore new therapeutic avenues to enhanced immunity against diseases. The review intended to highlight the importance of garlic (Allium sativum), green tea (Camellia sinensis), ginger (Zingiber officinale), purple coneflower (Echinacea), black cumin (Nigella sativa), licorice (Glycyrrhiza glabra), Astragalus and St. John's wort (Hypericum perforatum) as natural immune boosters. These plants are bestowed with functional ingredients that may provide protection against various menaces. Modes of their actions include boosting and functioning of immune system, activation and suppression of immune specialized cells, interfering in several pathways that eventually led to improvement in immune responses and defense system. In addition, some of these plants carry free radical scavenging and anti-inflammatory activities that are helpful against cancer insurgence. Nevertheless, interaction between drugs and herbs/botanicals should be well investigated before recommended for their safe use, and such information must be disseminated to the allied stakeholders.

Intervention of human breast cell carcinogenesis chronically induced by 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine

More than 85% of breast cancers are sporadic and attributable to long-term exposure to environmental carcinogens, such as those in the diet, through a multistep disease process progressing from non-cancerous to premalignant and malignant stages. The chemical carcinogen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is one of the most abundant heterocyclic amines found in high-temperature cooked meats and is recognized as a mammary carcinogen. However, the PhIP’s mechanism of action in breast cell carcinogenesis is not clear. Here, we demonstrated, for the first time, that cumulative exposures to PhIP at physiologically achievable, pico to nanomolar concentrations effectively induced progressive carcinogenesis of human breast epithelial MCF10A cells from a non-cancerous stage to premalignant and malignant stages in a dose- and exposure-dependent manner. Progressive carcinogenesis was measured by increasingly- acquired cancer-associated properties of reduced dependence on growth factors, anchorage-independent growth, acinar-conformational disruption, proliferation, migration, invasion, tumorigenicity with metastasis and increased stem-like cell populations. These biological changes were accompanied by biochemical and molecular changes, including upregulated H-Ras gene expression, extracellular signal-regulated kinase (ERK) pathway activation, Nox-1 expression, reactive oxygen species (ROS) elevation, increased HIF-1α, Sp1, tumor necrosis factor-α, matrix metalloproteinase (MMP)-2, MMP-9, aldehyde dehydrogenase activity and reduced E-cadherin. The Ras-ERK-Nox-ROS pathway played an important role in not only initiation but also maintenance of cellular carcinogenesis induced by PhIP. Using biological, biochemical and molecular changes as targeted endpoints, we identified that the green tea catechin components epicatechin-3-gallate and epigallocatechin-3-gallate, at non-cytotoxic doses, were capable of suppressing PhIP-induced cellular carcinogenesis and tumorigenicity.

Gerson regimen.

The Gerson regimen, developed by Max Gerson in the 1930s, is promoted as an alternative cancer treatment. It involves consuming fresh, raw fruit and vegetable juices, eliminating salt from the diet, taking supplements such as potassium, vitamin B12, thyroid hormone, pancreatic enzymes, and detoxifying liver with coffee enemas to stimulate metabolism. Gerson therapy is based on the theory that cancer is caused by alteration of cell metabolism by toxic environmental substances and processed food, which changes its sodium and potassium content. It emphasizes increasing potassium intake and minimizing sodium consumption in an effort to correct the electrolyte imbalance, repair tissue, and detoxify the liver. The coffee enemas are believed to cause dilation of bile ducts and excretion of toxic breakdown products by the liver and through the colon wall. None of these theories has been substantiated by scientific research. Despite proponents' claims of recovery rates as high as 70% to 90%, case reviews by the National Cancer Institute (NCI) and the New York County Medical Society found no evidence of usefulness for the Gerson diet. An NCI-sponsored study of Gonzalez therapy, which is similar to the Gerson diet, showed that patients with inoperable pancreatic adenocarcinoma who underwent standard chemotherapy with gemcitabine (Gemzar) survived three times longer and had better quality of life than those who chose enzyme treatment, which included pancreatic enzymes, nutritional supplements, detoxification, and an organic diet.

Dietary suppression of colonic cancer. Fiber or phytate?

The incidence of colonic cancer differs widely between various human populations. It has been suggested that dietary fiber content is of utmost importance and is inversely related to the occurrence of colonic cancer. However, high-fiber diets are not always correlated with low frequency of colonic cancer, suggesting the involvement of additional dietary constituents. Inositol hexaphosphate (phytic acid) is an abundant plant seed component present in many, but not all, fiber-rich diets. The authors have found that phytic acid is a potent inhibitor of iron-mediated generation of the hazardous oxidant, hydroxyl radical. Herein, the authors propose that inhibition of intracolonic hydroxyl radical generation, via the chelation of reactive iron by phytic acid, may help explain the suppression of colonic carcinogenesis and other inflammatory bowel diseases by diets rich in phytic acid.

Diet and cancer of the colon and rectum: a case-control study in China.

A case-control study was carried out in Harbin city to assess the role of diet in the aetiology of colorectal cancer. A total of 336 incident cases of histologically confirmed colorectal cancer (111 colon cancer and 225 rectal cancer) and an equal number of controls with other non-neoplastic diseases were interviewed in hospital wards. Data concerning the average frequency of consumption and amount consumed of single food items were obtained by a dietary history questionnaire. Odds ratios and their confidence limits were computed. Multiple regression for risk status was also used. Vegetables, particularly green vegetables, chives and celery, have a strong protective effect against colorectal cancer. Reduced consumption of meat, eggs, bean products and grain was associated with increasing risk for cancer of the rectum. Alcohol intake was found to be an important risk factor for developing colon cancer and male rectal cancer.

Assessment of normal bowel habits in the general adult population: the Popcol study.

OBJECTIVE: Defining normal stool habit is important when evaluating diarrhoea or constipation, but common confounders such as irritable bowel syndrome (IBS) or the intake of medications with gastrointestinal side effects have not been considered in earlier population based studies defining what is normal. We hypothesized that the exclusion of subjects with common confounders would help to better understand what are "normal bowel habits". We aimed to prospectively study bowel habits in a carefully studied random sample of the general population. MATERIAL AND METHODS: Two hundred and sixty-eight randomly selected subjects between 18 and 70 years completed symptom diaries for one week and were clinically evaluated by a gastroenterologist. They also had a colonoscopy and laboratory investigations to exclude organic disease. RESULTS: One hundred and twenty-four subjects had no organic gastrointestinal abnormality, IBS, or relevant medication; 98% of them had between three stools per day and three per week. Seventy-seven percent of all stools were normal, 12% hard, and 10% loose in consistency. Urgency was reported by 36%; straining by 47% and incomplete defecation by 46%. After the exclusion of subjects with organic abnormalities, women had significantly more symptoms than men in terms of abdominal pain, bloating, constipation, urgency, and feeling of incomplete evacuation but these gender differences disappeared after excluding subjects with IBS. CONCLUSIONS: This study confirms that normal stool frequency is between three per week and three per day. We could not demonstrate any gender or age differences in terms of stool frequency, defecatory symptoms or abdominal bloating. Some degree of urgency, straining, and incomplete evacuation should be considered normal.

Enhancement of immunity in the elderly by dietary supplementation with the probiotic Bifidobacterium lactis HN019.

BACKGROUND: The aging process can lead to a decline in cellular immunity. Therefore, the elderly could benefit from safe and effective interventions that restore cellular immune functions. OBJECTIVE: We determined whether dietary supplementation with the known immunostimulating probiotic Bifidobacterium lactis HN019 could enhance aspects of cellular immunity in elderly subjects. DESIGN: Thirty healthy elderly volunteers (age range: 63-84 y; median: 69 y) participated in a 3-stage dietary supplementation trial lasting 9 wk. During stage 1 (run-in), subjects consumed low-fat milk (200 mL twice daily for 3 wk) as a base-diet control. During stage 2 (intervention), they consumed milk supplemented with B. lactis HN019 in a typical dose (5 x 10(10) organisms/d) or a low dose (5 x 10(9) organisms/d) for 3 wk. During stage 3 (washout), they consumed low-fat milk for 3 wk. Changes in the relative proportions of leukocyte subsets and ex vivo leukocyte phagocytic and tumor-cell-killing activity were determined longitudinally by assaying peripheral blood samples. RESULTS: Increases in the proportions of total, helper (CD4(+)), and activated (CD25(+)) T lymphocytes and natural killer cells were measured in the subjects' blood after consumption of B. lactis HN019. The ex vivo phagocytic capacity of mononuclear and polymorphonuclear phagocytes and the tumoricidal activity of natural killer cells were also elevated after B. lactis HN019 consumption. The greatest changes in immunity were found in subjects who had poor pretreatment immune responses. In general, the 2 doses of B. lactis HN019 had similar effectiveness. CONCLUSION: B. lactis HN019 could be an effective probiotic dietary supplement for enhancing some aspects of cellular immunity in the elderly.

Resistant starch lowers fecal concentrations of ammonia and phenols in humans.

We investigated the effect of resistant starch (RS) on markers of colonic protein metabolism. Eleven subjects participated in a randomized crossover study in which they consumed either high-RS (39 +/- 3 g/d, -chi +/- SEM) or low-RS (5 +/- 0.4 g/d) diets for 3 wk. All other macronutrients were kept constant. During the high-RS diet daily excretion of fecal nitrogen increased from 1.84 +/- 0.15 to 2.86 +/- 0.42 g/d (P < 0.01) and excretion of fecal phenols fell from 9.2 +/- 1.4 to 5.3 +/- 0.8 mg/d (P < 0.01). Fecal concentrations of ammonia decreased from 397 +/- 33 to 278 +/- 49 microgram/g (P < 0.01) and phenols decreased from 69 +/- 8 to 39 +/- 10 microgram/g (P < 0.001). Daily output of urinary ammonia, urea, phenols, and total nitrogen did not change significantly, but pH decreased from 6.4 +/- 0.1 to 6.2 +/- 0.1 (P < 0.05) during the high-RS period. These results suggest that RS significantly attenuates the accumulation of potentially harmful byproducts of protein fermentation in the human colon.

Effects of dietary flaxseed lignan extract on symptoms of benign prostatic hyperplasia.

A flaxseed lignan extract containing 33% secoisolariciresinol diglucoside (SDG) was evaluated for its ability to alleviate lower urinary tract symptoms (LUTS) in 87 subjects with benign prostatic hyperplasia (BPH). A randomized, double-blind, placebo-controlled clinical trial with repeated measurements was conducted over a 4-month period using treatment dosages of 0 (placebo), 300, or 600 mg/day SDG. After 4 months of treatment, 78 of the 87 subjects completed the study. For the 0, 300, and 600 mg/day SDG groups, respectively, the International Prostate Symptom Score (IPSS) decreased -3.67 +/- 1.56, -7.33 +/- 1.18, and -6.88 +/- 1.43 (mean +/- SE, P = .100, < .001, and < .001 compared to baseline), the Quality of Life score (QOL score) improved by -0.71 +/- 0.23, -1.48 +/- 0.24, and -1.75 +/- 0.25 (mean +/- SE, P = .163 and .012 compared to placebo and P = .103, < .001, and < .001 compared to baseline), and the number of subjects whose LUTS grade changed from "moderate/severe" to "mild" increased by three, six, and 10 (P = .188, .032, and .012 compared to baseline). Maximum urinary flows insignificantly increased 0.43 +/- 1.57, 1.86 +/- 1.08, and 2.7 +/- 1.93 mL/second (mean +/- SE, no statistical significance reached), and postvoiding urine volume decreased insignificantly by -29.4 +/- 20.46, -19.2 +/- 16.91, and -55.62 +/- 36.45 mL (mean +/- SE, no statistical significance reached). Plasma concentrations of secoisolariciresinol (SECO), enterodiol (ED), and enterolactone (EL) were significantly raised after the supplementation. The observed decreases in IPSS and QOL score were correlated with the concentrations of plasma total lignans, SECO, ED, and EL. In conclusion, dietary flaxseed lignan extract appreciably improves LUTS in BPH subjects, and the therapeutic efficacy appeared comparable to that of commonly used intervention agents of alpha1A-adrenoceptor blockers and 5alpha-reductase inhibitors.

Effect of ascorbic acid and green tea on endogenous formation of N-nitrosodimethylamine and N-nitrosopiperidine in humans.

Many constituents present in the human diet may inhibit endogenous formation of N-nitroso compounds (NOC). Studies with human volunteers showed inhibiting effects of intake of ascorbic acid and green tea consumption on nitrosation using the N-nitrosoproline test. The aim of the present study was to evaluate the effects of ascorbic acid and green tea on urinary excretion of carcinogenic N-nitrosodimethylamine (NDMA) and N-nitrosopiperidine (NPIP) in humans. Twenty-five healthy female volunteers consumed a fish meal rich in amines as nitrosatable precursors in combination with intake of nitrate-containing drinking water at the Acceptable Daily Intake level during 7 consecutive days. During 1 week before and after nitrate intake a diet low in nitrate was consumed. Using the same protocol, the effect of two different doses of ascorbic acid (250 mg and 1 g/day) and two different doses of green tea (2 g and 4 g/day) on formation of NDMA and NPIP was studied. Mean nitrate excretion in urine significantly increased from control (76+/-24) to 167+/-25 mg/24 h. Intake of nitrate and fish resulted in a significant increase in mean urinary excretion of NDMA compared with the control weeks: 871+/-430 and 640+/-277 ng/24 h during days 1-3 and 4-7, respectively, compared with 385+/-196 ng/24 h (p<0.0002). Excretion of NPIP in urine was not related to nitrate intake and composition of the diet. Intake of 250 mg and 1 g of ascorbic acid per day resulted in a significant decrease in urinary NDMA excretion during days 4-7 (p=0.0001), but not during days 1-3. Also, consumption of four cups of green tea per day (2 g) significantly decreased excretion of NDMA during days 4-7 (p=0.0035), but not during days 1-3. Surprisingly, consumption of eight cups of green tea per day (4 g) significantly increased NDMA excretion during days 4-7 (p=0.0001), again not during days 1-3. This increase is probably a result of catalytic effects of tea polyphenols on nitrosation, or of another, yet unknown, mechanism. These results suggest that intake of ascorbic acid and moderate consumption of green tea can reduce endogenous NDMA formation.

The potential to intensify sulforaphane formation in cooked broccoli (Brassica oleracea var. italica) using mustard seeds (Sinapis alba).

Sulforaphane, a naturally occurring cancer chemopreventive, is the hydrolysis product of glucoraphanin, the main glucosinolate in broccoli. The hydrolysis requires myrosinase isoenzyme to be present in sufficient activity; however, processing leads to its denaturation and hence reduced hydrolysis. In this study, the effect of adding mustard seeds, which contain a more resilient isoform of myrosinase, to processed broccoli was investigated with a view to intensify the formation of sulforaphane. Thermal inactivation of myrosinase from both broccoli and mustard seeds was studied. Thermal degradation of broccoli glucoraphanin was investigated in addition to the effects of thermal processing on the formation of sulforaphane and sulforaphane nitrile. Limited thermal degradation of glucoraphanin (less than 12%) was observed when broccoli was placed in vacuum sealed bag (sous vide) and cooked in a water bath at 100°C for 8 and 12 min. Boiling broccoli in water prevented the formation of any significant levels of sulforaphane due to inactivated myrosinase. However, addition of powdered mustard seeds to the heat processed broccoli significantly increased the formation of sulforaphane. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

Fine and ultrafine particles of the diet: influence on the mucosal immune response and association with Crohn's disease.

Crohn's disease is a modern Western disease characterised by transmural inflammation of the gastrointestinal tract. It is of unknown aetiology, but evidence suggests that it results from a combination of genetic predisposition and environmental factors. Bacterial-sized microparticles (0.1-1.0 microm) are potent adjuvants in model antigen-mediated immune responses and are increasingly associated with disease. Microparticles of TiO2 and aluminosilicate accumulate in macrophages of human gut-associated lymphoid tissue where the earliest signs of lesions in Crohn's disease are observed. Dietary microparticles are of endogenous or exogenous origin. Endogenous microparticles dominate and are calcium phosphate (most probably hydroxyapatite), which precipitates in the lumen of the mid-distal gastrointestinal tract due to secretion of Ca and phosphate in the succus entericus. Exogenous dietary microparticles are contaminants (soil and/or dust) and food additives. TiO2, for example, is a food colourant, and aluminosilicates are anti-caking agents, although some aluminosilicates occur as natural contaminants. Food additives alone account for ingestion of approximately 10(12) particles/person per d. Possible mechanisms for the role of exogenous and endogenous dietary microparticles in promoting toleragenic or immune responses of gastrointestinal mucosal phagocytosis are discussed. In a double-blind randomised pilot study we have shown that a diet low in Ca and exogenous microparticles appears to alleviate the symptoms of ileal Crohn's disease, with a significant (P= 0.002) improvement in the Crohn's disease activity index. A multi-centre trial and further mechanistic studies at the cellular level are underway.

Influence of frequent and long-term bean consumption on colonic function and fermentation.

The objective of this study was to determine the influence of frequent and long-term consumption of legume seeds on colonic function. Two groups of subjects were studied--one group habitually consumed legume seeds as part of their normal diet, a second group only infrequently consumed legumes. No differences between these groups could be detected for fecal output and frequency, intestinal transit time, VFA excretion or fecal pH during 23-day study periods in which subjects consumed either their usual diet or 100 g red kidney beans, daily. However, the addition of beans to the diets of both groups provided significantly more dietary fiber, and produced greater fecal output and a higher concentration of VFA in feces. Fecal output appeared to be determined by two independent parameters--dietary fiber intake and VFA excretion. Beans provided a physiologically useful source of dietary fiber and favorably influenced colonic function.

mTORC1 activity as a determinant of cancer risk--rationalizing the cancer-preventive effects of adiponectin, metformin, rapamycin, and low-protein ...

Increased plasma levels of adiponectin, metformin therapy of diabetes, rapamycin administration in transplant patients, and lifelong consumption of low-protein plant-based diets have all been linked to decreased risk for various cancers. These benefits may be mediated, at least in part, by down-regulated activity of the mTORC1 complex, a key regulator of protein translation. By boosting the effective availability of the translation initiator eIF4E, mTORC1 activity promotes the translation of a number of "weak" mRNAs that code for proteins, often up-regulated in cancer, that promote cellular proliferation, invasiveness, and angiogenesis, and that abet cancer promotion and chemoresistance by opposing apoptosis. Measures which inhibit eIF4E activity, either directly or indirectly, may have utility not only for cancer prevention, but also for the treatment of many cancers in which eIF4E drives malignancy. Since eIF4E is overexpressed in many cancers, strategies which target eIF4E directly--some of which are now being assessed clinically--may have the broadest efficacy in this regard. Many of the "weak" mRNAs coding for proteins that promote malignant behavior or chemoresistance are regulated transcriptionally by NF-kappaB and/or Stat3, which are active in a high proportion of cancers; thus, regimens concurrently targeting eIF4E, NF-kappaB, and Stat3 may suppress these proteins at both the transcriptional and translational levels, potentially achieving a very marked reduction in their expression. Copyright © 2011 Elsevier Ltd. All rights reserved.

Influence of a five-day vegetarian diet on urinary levels of antibiotics and phthalate metabolites: a pilot study with "Temple Stay" participants.

Diet is purported to be means of exposure to many environmental contaminants. The purpose of this study is to understand the influence of dietary change on the levels of exposure to several environmental chemicals - in particular, antibiotics and phthalates. For this purpose, we examined the extent to which short-term changes in diet influenced the inadvertent exposure levels to these chemicals in an adult population. We recruited participants (n=25) of a five-day 'Temple Stay' program in Korea and collected urine samples before and after the program. We also conducted a questionnaire survey on participants' dietary patterns prior to their participation. During the program, participants followed the daily routines of Buddhist monks and maintained a vegetarian diet. Urinary levels of three antibiotics and their major metabolites, metabolites of four major phthalates, and malondialdehyde (MDA) as an oxidative stress biomarker were analyzed. The frequency and levels of detection for antibiotics and phthalates noticeably decreased during the program. Urinary MDA levels were significantly lower than before program participation (0.16 versus 0.27mg/g creatinine). Although the exposure to target compounds might be influenced by other behavioral patterns, these results suggest that even short-term changes in dietary behavior may significantly decrease inadvertent exposure to antibiotics and phthalates and hence may reduce oxidative stress levels. Copyright 2010 Elsevier Inc. All rights reserved.

Pharmacodynamic and pharmacokinetic study of oral Curcuma extract in patients with colorectal cancer.

Curcuma spp. extracts, particularly the dietary polyphenol curcumin, prevent colon cancer in rodents. In view of the sparse information on the pharmacodynamics and pharmacokinetics of curcumin in humans, a dose-escalation pilot study of a novel standardized Curcuma extract in proprietary capsule form was performed at doses between 440 and 2200 mg/day, containing 36-180 mg of curcumin. Fifteen patients with advanced colorectal cancer refractory to standard chemotherapies received Curcuma extract daily for up to 4 months. Activity of glutathione S-transferase and levels of a DNA adduct (M(1)G) formed by malondialdehyde, a product of lipid peroxidation and prostaglandin biosynthesis, were measured in patients' blood cells. Oral Curcuma extract was well tolerated, and dose-limiting toxicity was not observed. Neither curcumin nor its metabolites were detected in blood or urine, but curcumin was recovered from feces. Curcumin sulfate was identified in the feces of one patient. Ingestion of 440 mg of Curcuma extract for 29 days was accompanied by a 59% decrease in lymphocytic glutathione S-transferase activity. At higher dose levels, this effect was not observed. Leukocytic M(1)G levels were constant within each patient and unaffected by treatment. Radiologically stable disease was demonstrated in five patients for 2-4 months of treatment. The results suggest that (a) Curcuma extract can be administered safely to patients at doses of up to 2.2 g daily, equivalent to 180 mg of curcumin; (b) curcumin has low oral bioavailability in humans and may undergo intestinal metabolism; and (c) larger clinical trials of Curcuma extract are merited.

Effects of vitamins C and E on N-nitroso compound formation, carcinogenesis, and cancer.

The properties of N-nitroso compounds (NNC) and of vitamins C and E are briefly described. The author reviews the ability of vitamins C and E to inhibit NNC formation in chemical systems, in nitrite-preserved meat, in experimental animals and in humans. Dietary vitamins C and E both produced 30% to 60% inhibitions in most carcinogenesis experiments employing preformed carcinogens. Vitamin C reversed transformation in an in vitro system. Carcinogenicity tests of the vitamins are reviewed (vitamin C can promote bladder carcinogenesis). Intake of fresh fruits and vegetables (which contain vitamin C) is negatively correlated with cancer of the stomach, esophagus, larynx, mouth and cervix. For gastric and esophageal cancer, there is evidence that this association is due to an inhibition of in vivo NNC formation. Vitamin C is apparently not a useful treatment for cancer. The author supports the recommendation that fresh fruit and vegetable intake be increased to lower the risk of cancer.

Rarity of colon cancer in Africans is associated with low animal product consumption, not fiber.

OBJECTIVE: To investigate whether the rarity of colon cancer in black Africans (prevalence, < 1:100,000) can be accounted for by dietary factors considered to reduce risk, and by differences in colonic bacterial fermentation. METHODS: Samples of the adult black South African population were drawn from several rural and urban regions. Food consumption was assessed by home visits, food frequency questionnaires, computerized analysis of 72-h dietary recall, and blood sampling. Colonic fermentation was measured by breath H2 and CH4 response to a traditional meal, and to 10-g of lactulose. Cancer risk was estimated by measurement of epithelial proliferation indices (Ki-67 and BrdU) in rectal mucosal biopsies. Results were evaluated by comparison to measurements in high-risk white South Africans (prevalence, 17:100,000). RESULTS: Epithelial proliferation was significantly lower in rural and urban blacks than whites. The diets of all the black subgroups were characterized by a low animal product and high boiled maize-meal content, whereas whites consumed more fresh animal products, cheese, and wheat products. Blacks consumed below RDA quantities of fiber (43% of RDA), vitamin A (78%), C (62%), folic acid (80%) and calcium (67%), whereas whites consumed more animal protein (177% of RDA) and fat (153%). Fasting and food-induced breath methane production was two to three times higher in blacks. CONCLUSIONS: The low prevalence of colon cancer in black Africans cannot be explained by dietary "protective" factors, such as, fiber, calcium, vitamins A, C and folic acid, but may be influenced by the absence of "aggressive" factors, such as excess animal protein and fat, and by differences in colonic bacterial fermentation.

Hydrogen sulfide induces direct radical-associated DNA damage.

Hydrogen sulfide (H(2)S) is produced by indigenous sulfate-reducing bacteria in the large intestine and represents an environmental insult to the colonic epithelium. Clinical studies have linked the presence of either sulfate-reducing bacteria or H(2)S in the colon with chronic disorders such as ulcerative colitis and colorectal cancer, although at this point, the evidence is circumstantial and underlying mechanisms remain undefined. We showed previously that sulfide at concentrations similar to those found in the human colon induced genomic DNA damage in mammalian cells. The present study addressed the nature of the DNA damage by determining if sulfide is directly genotoxic or if genotoxicity requires cellular metabolism. We also questioned if sulfide genotoxicity is mediated by free radicals and if DNA base oxidation is involved. Naked nuclei from untreated Chinese hamster ovary cells were treated with sulfide; DNA damage was induced by concentrations as low as 1 micromol/L. This damage was effectively quenched by cotreatment with butylhydroxyanisole. Furthermore, sulfide treatment increased the number of oxidized bases recognized by formamidopyrimidine [fapy]-DNA glycosylase. These results confirm the genotoxicity of sulfide and strongly implicate that this genotoxicity is mediated by free radicals. These observations highlight the possible role of sulfide as an environmental insult that, given a predisposing genetic background, may lead to genomic instability or the cumulative mutations characteristic of colorectal cancer.

In vitro antimutagenicity of curcumin against environmental mutagens.

The effects of curcumin, the yellow pigment of the spice, turmeric (Curcuma longa) on the mutagenicity of several environmental mutagens were investigated in the Salmonella/microsome test with or without Aroclor 1254-induced rat-liver homogenate (S-9 mix). With Salmonella typhimurium strain TA98 in the presence of S-9 mix, curcumin inhibited the mutagenicity of bidi and cigarette smoke condensates, tobacco and masheri extracts, benzo[a]pyrne and dimethyl benzo[a]anthracene in a dose-dependent manner. Curcumin did not influence the mutagenicity without S-9 mix of sodium azide, monoacetylhydrazine and streptozocin in strain TA100 nor of 4-nitrophenylenediamine in strain TA98. Our observations indicate that curcumin may alter the metabolic activation and detoxification of mutagens.

Plasma and urinary alkylresorcinol metabolites as potential biomarkers of breast cancer risk in Finnish women: a pilot study.

Alkylresorcinols (ARs) are shown to be good biomarkers of consumption of rye and whole-grain wheat products in man. The aim of this pilot study was to investigate AR metabolites as potential biomarkers of breast cancer (BC) risk in Finnish women since intake of cereal fiber and its components has been proposed to reduce this risk through an effect on the enterohepatic circulation of estrogens. This was a cross-sectional and observational pilot study. A total of 20 omnivores, 20 vegetarians, and 16 BC women (6-12 mo after operation) were investigated on 2 occasions 6 mo apart. Dietary intake (5-days record), plasma/urinary AR metabolites [3,5-dihydroxybenzoic acid (DHBA) and 3-(3,5-dihydroxyphenyl)-1-propanoic acid (DHPPA)] and plasma/urinary enterolactone were measured. The groups were compared using nonparametric tests. We observed that plasma DHBA (P = 0.007; P = 0.03), plasma DHPPA (P = 0.02; P = 0.01), urinary DHBA (P = 0.001; P = 0.003), urinary DHPPA (P = 0.001; P = 0.001), and cereal fiber intake (P = 0.007; P = 0.003) were significantly lower in the BC group compared to the vegetarian and omnivore groups, respectively. Based on measurements of AR metabolites in urine and in plasma, whole-grain rye and wheat cereal fiber intake is low in BC subjects. Thus, urinary and plasma AR metabolites may be used as potential biomarkers of BC risk in women. This novel approach will likely also facilitate studies of associations between rye and whole-grain wheat cereal fiber intake and other diseases. Our findings should, however, be confirmed with larger subject populations.

Potential efficacy of broccoli sprouts as a unique supplement for management of type 2 diabetes and its complications.

Functional foods and their nutraceutical components are now considered as supplementary treatments in type 2 diabetes and prevention of its long-term complications. Young broccoli sprouts as a functional food contain many bioactive compounds specially sulforaphane. In hyperglycemic and oxidative conditions, sulforaphane has the potential to activate the NF-E2-related factor-2 (Nrf2)-dependent antioxidant response-signaling pathway, induces phase 2 enzymes, attenuates oxidative stress, and inactivates nuclear factor kappa-B (NF-κB), a key modulator of inflammatory pathways. Interestingly, sulforaphane induces some peroxisome proliferator-activated receptors, which contribute to lipid metabolism and glucose homeostasis. In animal and in vitro models, sulforaphane also shows antihypertensive, anticancer, cardioprotective, and hypocholesterolemic capacity, and has bactericidal properties against Helicobacter pylori. Supplementation of type 2 diabetics with high sulforaphane content broccoli sprouts resulted in increased total antioxidant capacity of plasma and in decreased oxidative stress index, lipid peroxidation, serum triglycerides, oxidized low-density lipoprotein (LDL)/LDL-cholesterol ratio, serum insulin, insulin resistance, and serum high-sensitive C-reactive protein. Sulforaphane could prevent nephropathy, diabetes-induced fibrosis, and vascular complications. Potential efficacy of sulforaphane and probably other bioactive components of young broccoli sprouts makes it as an excellent choice for supplementary treatment in type 2 diabetes.

Meat-Related Compounds and Colorectal Cancer Risk by Anatomical Subsite

Since meat may be involved in the etiology of colorectal cancer, associations between meat-related compounds were examined to elucidate underlying mechanisms in a population-based case-control study. Participants (989 cases/1,033 healthy controls) completed a food frequency questionnaire with a meat-specific module. Multivariable logistic regression was used to examine associations between meat variables and colorectal cancer; polytomous logistic regression was used for subsite-specific analyses. The following significant positive associations were observed for meat-related compounds: 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (DiMeIQx) and colorectal, distal colon, and rectal tumors; 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) and colorectal and colon cancer tumors; nitrites/nitrates and proximal colon cancer; 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and rectal cancer; and benzo[a]pyrene and rectal cancer (P-trends < 0.05 ). For analyses by meat type, cooking method, and doneness preference, positive associations between red processed meat and proximal colon cancer and pan-fried red meat and colorectal cancer were found (P-trends < 0.05). Inverse associations were observed between unprocessed poultry and colorectal, colon, proximal colon, and rectal tumors; grilled/barbequed poultry and proximal colon cancer; and well-done/charred poultry and colorectal, colon, and proximal colon tumors (P-trends < 0.05). HCAs, PAHs, nitrites, and nitrates may be involved in colorectal cancer etiology. Further examination into the unexpected inverse associations between poultry and colorectal cancer is warranted.

The protective effect of the flavonoids on food-mutagen-induced DNA damage in peripheral blood lymphocytes from colon cancer patients.

The food mutagens IQ (2-amino-3-methylimidazo[4,5-f]quinoline) and PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine) are heterocyclic amines (HCA), generated when heating proteinaceous food. This study investigates the protective potential of the flavonoids quercetin (Q) and rutin (R) against oxidative stress induced in vitro by IQ and PhIP in lymphocytes from healthy individuals and untreated, newly diagnosed colon cancer patients using the Comet assay. In the presence of up to 500μM Q and R, the DNA damage resulting from a high dose of PhIP (75μM) or IQ (150μM) was significantly reduced (P<0.001) to levels comparable to six times lower IQ or 7.5 times lower PhIP doses. Lymphocytes from colon cancer patients had greater baseline DNA damage than those from healthy individuals (P<0.01) and this higher level of damage was also observed throughout in vitro treatment. Except for the >50years of age group and male gender, confounding factors such as smoking, drinking and/or dietary habits were not found to be significant. In conclusion, flavonoids reduced oxidative stress caused by food mutagens in vitro in lymphocytes of healthy individuals and colon cancer patients. Thus, dietary supplementation with flavonoid-rich vegetables and fruits may prove very effective in protecting against oxidative stress. Copyright © 2011 Elsevier Ltd. All rights reserved.

Fecal weight, colon cancer risk, and dietary intake of nonstarch polysaccharides (dietary fiber)

Low fecal weight and slow bowel transit time are thought to be associated with bowel cancer risk, but few published data defining bowel habits in different communities exist. Therefore, data on stool weight were collected from 20 populations in 12 countries to define this risk more accurately, and the relationship between stool weight and dietary intake of nonstarch polysaccharides (NSP) (dietary fiber) was quantified. In 220 healthy U.K. adults undertaking careful fecal collections, median daily stool weight was 106 g/day (men, 104 g/day; women, 99 g/day; P = 0.02) and whole-gut transit time was 60 hours (men, 55 hours; women, 72 hours; P = 0.05); 17% of women, but only 1% of men, passed < 50 g stool/day. Data from other populations of the world show average stool weight to vary from 72 to 470 g/day and to be inversely related to colon cancer risk (r = -0.78). Meta-analysis of 11 studies in which daily fecal weight was measured accurately in 26 groups of people (n = 206) on controlled diets of known NSP content shows a significant correlation between fiber intake and mean daily stool weight (r = 0.84). Stool weight in many Westernized populations is low (80-120 g/day), and this is associated with increased colon cancer risk. Fecal output is increased by dietary NSP. Diets characterized by high NSP intake (approximately 18 g/day) are associated with stool weights of 150 g/day and should reduce the risk of bowel cancer.

Probiotics for preventing acute upper respiratory tract infections.

BACKGROUND: Probiotics may improve a person's health by regulating their immune function. Some studies show that probiotic strains can prevent respiratory infections. However, no evidence of the benefits of probiotics for acute upper respiratory tract infections (URTIs) and related potential adverse effects has been published. OBJECTIVES: To assess the effectiveness and safety of probiotics for preventing acute URTIs. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 2), which includes the Cochrane Acute Respiratory Infections Group's Specialised Register, MEDLINE (Ovid) (1950 to May week 1, 2011), EMBASE (1974 to May 2011), Web of Science which includes Science Citation Index (from 1900 to May 2011) and Conference Proceedings Citation Index (from 1991 to May 2011), the Chinese Biomedical Literature Database, which includes the China Biological Medicine Database (from 1978 to May 2011), the Chinese Medicine Popular Science Literature Database (from 2000 to May 2011) and the Masters Degree Dissertation of Beijing Union Medical College Database (from 1981 to May 2011). SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing probiotics with placebo to prevent acute URTIs. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed eligibility, quality of trials and extracted data. MAIN RESULTS: We included 14 RCTs, although we could only extract available data to meta-analyse in 10 trials which involved 3451 participants. We found that probiotics were better than placebo when measuring the number of participants experiencing episodes of acute URTI: at least one episode: odds ratio (OR) 0.58; 95% confidence interval (CI) 0.36 to 0.92; at least three episodes: OR 0.53; 95% CI 0.36 to 0.80; rate ratio of episodes of acute URTI: rate ratio 0.88; 95% CI 0.81 to 0.96; and reduced antibiotic prescription rates for acute URTIs: OR 0.67; 95% CI 0.45 to 0.98. Probiotics and placebo were similar when measuring the mean duration (MD) of an episode of acute URTI: MD -0.29; 95% CI -3.71 to 3.13 and adverse events: OR 0.92; 95% CI 0.37 to 2.28. Side effects of probiotics were minor and gastrointestinal symptoms were the most common. We found that some subgroups had a high level of heterogeneity when conducting pooled analyses. AUTHORS' CONCLUSIONS: Probiotics were better than placebo in reducing the number of participants experiencing episodes of acute URTIs, the rate ratio of episodes of acute URTI and reducing antibiotic use. This indicates that probiotics may be more beneficial than placebo for preventing acute URTIs. However, the results have some limitations and there were no data for older people.

Antioxidant levels and inhibition of cancer cell proliferation in vitro by extracts from organically and conventionally cultivated strawberries.

The effects of extracts from five cultivars of strawberries on the proliferation of colon cancer cells HT29 and breast cancer cells MCF-7 were investigated, and possible correlations with the levels of several antioxidants were analyzed. In addition, the effects of organic cultivation compared to conventional cultivation on the content of antioxidants in the strawberries and strawberry extracts on the cancer cell proliferation were investigated. The ratio of ascorbate to dehydroascorbate was significantly higher in the organically cultivated strawberries. The strawberry extracts decreased the proliferation of both HT29 cells and MCF-7 cells in a dose-dependent way. The inhibitory effect for the highest concentration of the extracts was in the range of 41-63% (average 53%) inhibition compared to controls for the HT29 cells and 26-56% (average 43%) for MCF-7 cells. The extracts from organically grown strawberries had a higher antiproliferative activity for both cell types at the highest concentration than the conventionally grown, and this might indicate a higher content of secondary metabolites with anticarcinogenic properties in the organically grown strawberries. For HT29 cells, there was a negative correlation at the highest extract concentration between the content of ascorbate or vitamin C and cancer cell proliferation, whereas for MCF-7 cells, a high ratio of ascorbate to dehydroascorbate correlated with a higher inhibition of cell proliferation at the second highest concentration. The significance of the effect of ascorbate on cancer cell proliferation might lie in a synergistic action with other compounds.

Inactivation of Tautomerase Activity of Macrophage Migration Inhibitory Factor by Sulforaphane: A Potential Biomarker for Anti-inflammatory Intervention

Background Macrophage migration inhibitory factor (MIF), a proinflammatory cytokine with keto-enol tautomerase activity, rises rapidly in response to inflammation, and is elevated in many chronic diseases. Isothiocyanates, such as sulforaphane from broccoli, are very potent inactivators of MIF tautomerase activity. A simple rapid method for determining this activity in tissues and body fluids may therefore be valuable for assessing severity of inflammation and efficacy of intervention. Methods Existing spectrophotometric assays of MIF, based on conversion of methyl L-dopachrome to methyl 5,6-dihydroxyindole-2-carboxylate and associated loss of absorption at 475 nm, lack sensitivity. Assay sensitivity and efficiency were markedly improved by reducing the nonenzymatic rate, by lowering pH to 6.2, replacing phosphate (which catalyzes the reaction) with Bis-Tris buffer, and converting to a microtiter plate format. Results A structure-potency study of MIF tautomerase inactivation by isothiocyanates showed that sulforaphane, benzyl, n-hexyl, and phenethyl isothiocyanates were especially potent. MIF tautomerase could be readily quantified in human urine concentrated by ultrafiltration. This activity comprised: (i) a heat-labile, sulforaphane-inactivated macromolecular fraction (presumably MIF) that was concentrated during ultrafiltration; (ii) a flow-through fraction, with constant activity during filtration, that was heat-stable, and insensitive to sulforaphane. Administration of the sulforaphane precursor glucoraphanin to human volunteers almost completely abolished urinary tautomerase activity, which was recovered over many hours. Conclusions A simple, rapid, quantitative MIF tautomerase assay has been developed as a potential biomarker for assessing inflammatory severity and effectiveness of intervention. Impact An improved assay for measuring MIF tautomerase activity and its applications are described.

Biocompatibility of micro- and nano-particles in the colon. Part II.

Pathological colonic tissues were investigated with an Environmental Scanning Electron Microscope technique to verify the presence of inorganic, non-biodegradable pollutants, i.e. micro- and nano-debris of exogenous origin, after debris in liver and kidney had been discovered. In all, 18 samples of colon tissues affected by cancer and Crohn's disease were evaluated and found in all the cases to contain micro- and nano-particles. Their chemistry, detected with an X-ray microprobe, indicated a heterogeneous nature, whereas the size of the particles was homogeneous. Three control samples of healthy, young, cadavers were analysed and showed the absence of debris within the normal, healthy colon mucosa. The study reveals the presence of particulate debris, generally considered as biocompatible, in pathological specimens of human colon. The findings suggest a possible link between the presence of such particles and the underlying pathology in the cases analysed.

Immunomodulatory effects of a standardized Lycium barbarum fruit juice in Chinese older healthy human subjects.

Lycium barbarum has been traditionally used in combination with several herbs for medicinal properties, but systematic modern clinical evaluation as a single herb has not been reported. To examine the systematic effects of L. barbarum on immune function, general well-being, and safety, we tested the effects of a standardized L. barbarum fruit juice (GoChi, FreeLife International, Phoenix, AZ, USA) at 120 mL/day, equivalent to at least 150 g of fresh fruit, the amount traditionally used, or placebo for 30 days in a randomized, double-blind, placebo-controlled clinical study in 60 older healthy adults (55-72 years old). The GoChi group showed a statistically significant increase in the number of lymphocytes and levels of interleukin-2 and immunoglobulin G compared to pre-intervention and the placebo group, whereas the number of CD4, CD8, and natural killer cells or levels of interleukin-4 and immunoglobulin A were not significantly altered. The placebo group showed no significant changes in any immune measures. Whereas the GoChi group showed a significant increase in general feelings of well-being, such as fatigue and sleep, and showed a tendency for increased short-term memory and focus between pre- and post-intervention, the placebo group showed no significant positive changes in these measures. No adverse reactions, abnormal symptoms, or changes in body weight, blood pressure, pulse, visual acuity, urine, stool, or blood biochemistry were seen in either group. In conclusion, daily consumption of GoChi significantly increased several immunological responses and subjective feelings of general well-being without any adverse reactions.

Influence of piperine on the pharmacokinetics of curcumin in animals and human volunteers.

The medicinal properties of curcumin obtained from Curcuma longa L. cannot be utilised because of poor bioavailability due to its rapid metabolism in the liver and intestinal wall. In this study, the effect of combining piperine, a known inhibitor of hepatic and intestinal glucuronidation, was evaluated on the bioavailability of curcumin in rats and healthy human volunteers. When curcumin was given alone, in the dose 2 g/kg to rats, moderate serum concentrations were achieved over a period of 4 h. Concomitant administration of piperine 20 mg/kg increased the serum concentration of curcumin for a short period of 1-2 h post drug. Time to maximum was significantly increased (P < 0.02) while elimination half life and clearance significantly decreased (P < 0.02), and the bioavailability was increased by 154%. On the other hand in humans after a dose of 2 g curcumin alone, serum levels were either undetectable or very low. Concomitant administration of piperine 20 mg produced much higher concentrations from 0.25 to 1 h post drug (P < 0.01 at 0.25 and 0.5 h; P < 0.001 at 1 h), the increase in bioavailability was 2000%. The study shows that in the dosages used, piperine enhances the serum concentration, extent of absorption and bioavailability of curcumin in both rats and humans with no adverse effects.

Dietary microparticles implicated in Crohn's disease can impair macrophage phagocytic activity and act as adjuvants in the presence of bacterial st...

OBJECTIVE AND DESIGN: Western diets regularly expose the gastrointestinal tract (GI) to large quantities ( > 10(12)/day) of man-made, submicron-sized, particles derived from food additives and excipients. These are taken up by M cells, accumulate in gut macrophages, and may influence the aetiology of inflammatory bowel diseases (IBD). MATERIALS: We investigated the effects of common dietary microparticles on the function of macrophages from healthy donors or active Crohn's disease (CD) patients. METHODS: Macrophages were incubated for 24 h with microparticles before being assayed for cytokine production and phagocytic activity. RESULTS: Microparticles alone were non-stimulatory but, in the presence of bacterial antigens such as LPS, they could act as adjuvants to induce potent cytokine responses. Uptake of high concentrations of microparticles also impaired macrophage phagocytic capacity - but not their ability - to take up 2microM fluorescent beads. CONCLUSIONS: While dietary microparticles alone have limited effects on basic macrophage functions, their ability to act as adjuvants could aggravate ongoing inflammatory responses towards bacterial antigens in the GI tract.

Vegan proteins may reduce risk of cancer, obesity, and cardiovascular disease by promoting increased glucagon activity.

Amino acids modulate the secretion of both insulin and glucagon; the composition of dietary protein therefore has the potential to influence the balance of glucagon and insulin activity. Soy protein, as well as many other vegan proteins, are higher in non-essential amino acids than most animal-derived food proteins, and as a result should preferentially favor glucagon production. Acting on hepatocytes, glucagon promotes (and insulin inhibits) cAMP-dependent mechanisms that down-regulate lipogenic enzymes and cholesterol synthesis, while up-regulating hepatic LDL receptors and production of the IGF-I antagonist IGFBP-1. The insulin-sensitizing properties of many vegan diets--high in fiber, low in saturated fat--should amplify these effects by down-regulating insulin secretion. Additionally, the relatively low essential amino acid content of some vegan diets may decrease hepatic IGF-I synthesis. Thus, diets featuring vegan proteins can be expected to lower elevated serum lipid levels, promote weight loss, and decrease circulating IGF-I activity. The latter effect should impede cancer induction (as is seen in animal studies with soy protein), lessen neutrophil-mediated inflammatory damage, and slow growth and maturation in children. In fact, vegans tend to have low serum lipids, lean physiques, shorter stature, later puberty, and decreased risk for certain prominent 'Western' cancers; a vegan diet has documented clinical efficacy in rheumatoid arthritis. Low-fat vegan diets may be especially protective in regard to cancers linked to insulin resistance--namely, breast and colon cancer--as well as prostate cancer; conversely, the high IGF-I activity associated with heavy ingestion of animal products may be largely responsible for the epidemic of 'Western' cancers in wealthy societies. Increased phytochemical intake is also likely to contribute to the reduction of cancer risk in vegans. Regression of coronary stenoses has been documented during low-fat vegan diets coupled with exercise training; such regimens also tend to markedly improve diabetic control and lower elevated blood pressure. Risk of many other degenerative disorders may be decreased in vegans, although reduced growth factor activity may be responsible for an increased risk of hemorrhagic stroke. By altering the glucagon/insulin balance, it is conceivable that supplemental intakes of key non-essential amino acids could enable omnivores to enjoy some of the health advantages of a vegan diet. An unnecessarily high intake of essential amino acids--either in the absolute sense or relative to total dietary protein--may prove to be as grave a risk factor for 'Western' degenerative diseases as is excessive fat intake.

Biomonitoring of urinary metabolites of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) following human consumption of cooked chicken.

Human risk assessment of exposure to 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) through the diet may be improved by conducting biomonitoring studies comparing metabolism in humans and rodents. Eleven volunteers ingested a meal of cooked chicken containing 4 -OH-PhIP and PhIP in amounts of 0.6 and 0.8microg/kg, respectively and urine was collected for the next 16h. The large number of PhIP metabolites was by treatment of the urine samples with hydrazine hydrate and hydrolytic enzymes reduced to three substances, 4'-OH-PhIP, PhIP and 5-OH-PhIP of which the first is a biomarker for detoxification and the last a biomarker for activation. The eleven volunteers eliminated large amounts of 4'-OH-PhIP in the urine. The majority of which could be accounted for by the presence of 4'-OH-PhIP in the fried chicken, showing that PhIP only to a small extent (11%) was metabolised to 4'-OH-PhIP. A larger fraction of the PhIP exposure, 38%, was recovered as PhIP and the largest fraction (51%) was recovered as 5-OH-PhIP suggesting that PhIP in humans to a large extent is metabolised to reactive substances. In rats, less than 1% of the dose of PhIP was eliminated as 5-OH-PhIP, suggesting that human cancer risk from exposure to PhIP is considerable higher than risk estimations based on extrapolation from rodent bioassays.

Plant-derived health: the effects of turmeric and curcuminoids.

Plants contain numerous polyphenols, which have been shown to reduce inflammation and hereby to increase resistance to disease. Examples of such polyphenols are isothiocyanates in cabbage and broccoli, epigallocatechin in green tee, capsaicin in chili peppers, chalones, rutin and naringenin in apples, resveratrol in red wine and fresh peanuts and curcumin/curcuminoids in turmeric. Most diseases are maintained by a sustained discreet but obvious increased systemic inflammation. Many studies suggest that the effect of treatment can be improved by a combination of restriction in intake of proinflammatory molecules such as advanced glycation end products (AGE), advanced lipoperoxidation end products (ALE), and rich supply of antiinflammatory molecules such as plant polyphenols. To the polyphenols with a bulk of experimental documentation belong the curcuminoid family and especially its main ingredient, curcumin. This review summarizes the present knowledge about these turmericderived ingredients, which have proven to be strong antioxidants and inhibitors of cyclooxigenase-2 (COX-2), lipoxygenase (LOX) and nuclear factor kappa B (NF-kappaB) but also AGE. A plethora of clinical effects are reported in various experimental diseases, but clinical studies in humans are few. It is suggested that supply of polyphenols and particularly curcuminoids might be value as complement to pharmaceutical treatment, but also prebiotic treatment, in conditions proven to be rather therapy-resistant such as Crohn's, long-stayed patients in intensive care units, but also in conditions such as cancer, liver cirrhosis, chronic renal disease, chronic obstructive lung disease, diabetes and Alzheimer's disease.

Characterization of bacteria, clostridia and Bacteroides in faeces of vegetarians using qPCR and PCR-DGGE fingerprinting.

BACKGROUND/AIMS: This study aimed to investigate the quantitative and qualitative changes of bacteria, Bacteroides, Bifidobacterium and Clostridium cluster IV in faecal microbiota associated with a vegetarian diet. METHODS: Bacterial abundances were measured in faecal samples of 15 vegetarians and 14 omnivores using quantitative PCR. Diversity was assessed with PCR-DGGE fingerprinting, principal component analysis (PCA) and Shannon diversity index. RESULTS: Vegetarians had a 12% higher abundance of bacterial DNA than omnivores, a tendency for less Clostridium cluster IV (31.86 +/- 17.00%; 36.64 +/- 14.22%) and higher abundance of Bacteroides (23.93 +/- 10.35%; 21.26 +/- 8.05%), which were not significant due to high interindividual variations. PCA suggested a grouping of bacteria and members of Clostridium cluster IV. Two bands appeared significantly more frequently in omnivores than in vegetarians (p < 0.005 and p < 0.022). One was identified as Faecalibacterium sp. and the other was 97.9% similar to the uncultured gut bacteriumDQ793301. CONCLUSIONS: A vegetarian diet affects the intestinal microbiota, especially by decreasing the amount and changing the diversity of Clostridium cluster IV. It remains to be determined how these shifts might affect the host metabolism and disease risks. Copyright 2009 S. Karger AG, Basel.

Why do African Americans get more colon cancer than Native Africans?

The incidence of colorectal cancer (CRC) is dramatically higher in African Americans (AAs) than in Native Africans (NAs) (60:100,000 vs. <1:100,000) and slightly higher than in Caucasian Americans (CAs). To explore whether the difference could be explained by interactions between diet and colonic bacterial flora, we compared randomly selected samples of healthy 50- to 65-y-old AAs (n = 17) with NAs (n = 18) and CAs (n = 17). Diet was measured by 3-d recall, and colonic metabolism by breath hydrogen and methane responses to oral lactulose. Fecal samples were cultured for 7-alpha dehydroxylating bacteria and Lactobacillus plantarum. Colonoscopic mucosal biopsies were taken to measure proliferation rates. In comparison with NAs, AAs consumed more (P < 0.01) protein (94 +/- 9.3 vs. 58 +/- 4.1 g/d) and fat (114 +/- 11.2 vs. 38 +/- 3.0 g/d), meat, saturated fat, and cholesterol. However, they also consumed more (P < 0.05) calcium, vitamin A, and vitamin C, and fiber intake was the same. Breath hydrogen was higher (P < 0.0001) and methane lower in AAs, and fecal colony counts of 7-alpha dehydroxylating bacteria were higher and of Lactobacilli were lower. Colonic crypt cell proliferation rates were dramatically higher in AAs (21.8 +/- 1.1% vs. 3.2 +/- 0.8% labeling, P < 0.0001). In conclusion, the higher CRC risk and mucosal proliferation rates in AAs than in NAs were associated with higher dietary intakes of animal products and higher colonic populations of potentially toxic hydrogen and secondary bile-salt-producing bacteria. This supports our hypothesis that CRC risk is determined by interactions between the external (dietary) and internal (bacterial) environments.

Green tea: nature's defense against malignancies.

The current practice of introducing phytochemicals to support the immune system or fight against diseases is based on centuries old traditions. Nutritional support is a recent advancement in the domain of diet-based therapies; green tea and its constituents are one of the important components of these strategies to prevent and cure various malignancies. The anti-carcinogenic and anti-mutagenic activities of green tea were highlighted some years ago suggesting that it could reduce the prevalence of cancer and even provide protection. The pharmacological actions of green tea are mainly attributed to polyphenols that includes epigallocatechin-3-gallate (EGCG), epicatechin, epicatechin-3-gallate, epigallocatechin. Green tea and its components effectively mitigate cellular damage arising due to oxidative stress. Green tea is supposed to enhance humoral and cell-mediated immunity, decreasing the risk of certain cancers, and may have certain advantage in treating inflammatory disorders. Much of the cancer chemopreventive properties of green tea are mediated by EGCG that induces apoptosis and promotes cell growth arrest, by altering the expression of cell cycle regulatory proteins, activating killer caspases, and suppressing nuclear factor kappa-B activation. Besides, it regulates and promotes IL-23 dependent DNA repair and stimulates cytotoxic T cells activities in a tumor microenvironment. It also blocks carcinogenesis by modulating the signal transduction pathways involved in cell proliferation, transformation, inflammation and metastasis. The review is intended to highlight the chemistry of green tea, its antioxidant potential, its immunopotentiating properties and mode of action against various cancer cell lines that showed its potential as a chemopreventive agent against colon, skin, lung, prostate, and breast cancer.

Fisetin inhibits various attributes of angiogenesis in vitro and in vivo--implications for angioprevention.

Studies have shown that fisetin, a small phytochemical molecule, has antitumor activity; however, its antiangiogenic activity has not yet been examined. Accordingly, herein, we investigated the antiangiogenic efficacy and associated mechanisms of fisetin in human umbilical vein endothelial cells (HUVECs). Fisetin (10-50 μM) strongly inhibited the regular serum plus growth supplement- and vascular endothelial growth factor (VEGF)-induced growth (up to 92%, P < 0.001) and survival (up to 16%, P < 0.001) of HUVEC in a dose- and time-dependent manner. Fisetin also caused cell cycle arrest at G(1) (strong) and G(2)/M (moderate) phases together with a decrease in cyclin D1 and an increase in p53 levels. Fisetin-caused cell death was accompanied by decreased expression of survivin and an increase in cleaved levels of caspases-3 and -7 and poly-(ADP-ribose) polymerase along with an increased ratio of Bax to Bcl-2. Furthermore, fisetin inhibited capillary-like tube formation on Matrigel (up to 85%, P < 0.001) as well as migration (up to 66%, P < 0.001), which were associated with decreased expression of endothelial nitric oxide synthase (eNOS) and VEGF in HUVEC. It also decreased the expression of eNOS, VEGF, inducible nitric oxide synthase, matrix metalloproteinase-2 and -9 in A549 and DU145 human cancer cells. In vivo matrigel plug assay in mice showed significant decrease in size (up to 43%, P < 0.001), vascularization and hemoglobin content (up to 94%, P < 0.001) in the plugs from fisetin-treated, compared with control mice. Overall, these results suggest that fisetin inhibits various attributes of angiogenesis, which might contribute to its reported antitumor effects, and therefore, fisetin warrants further investigation for its angiopreventive potential toward cancer control.

Non-Specific Protein Modifications by a Phytochemical Induce Heat Shock Response for Self-Defense

Accumulated evidence shows that some phytochemicals provide beneficial effects for human health. Recently, a number of mechanistic studies have revealed that direct interactions between phytochemicals and functional proteins play significant roles in exhibiting their bioactivities. However, their binding selectivities to biological molecules are considered to be lower due to their small and simple structures. In this study, we found that zerumbone, a bioactive sesquiterpene, binds to numerous proteins with little selectivity. Similar to heat-denatured proteins, zerumbone-modified proteins were recognized by heat shock protein 90, a constitutive molecular chaperone, leading to heat shock factor 1-dependent heat shock protein induction in hepa1c1c7 mouse hepatoma cells. Furthermore, oral administration of this phytochemical up-regulated heat shock protein expressions in the livers of Sprague-Dawley rats. Interestingly, pretreatment with zerumbone conferred a thermoresistant phenotype to hepa1c1c7 cells as well as to the nematode Caenorhabditis elegans. It is also important to note that several phytochemicals with higher hydrophobicity or electrophilicity, including phenethyl isothiocyanate and curcumin, markedly induced heat shock proteins, whereas most of the tested nutrients did not. These results suggest that non-specific protein modifications by xenobiotic phytochemicals cause mild proteostress, thereby inducing heat shock response and leading to potentiation of protein quality control systems. We considered these bioactivities to be xenohormesis, an adaptation mechanism against xenobiotic chemical stresses. Heat shock response by phytochemicals may be a fundamental mechanism underlying their various bioactivities.

Nutrients and contaminants in human milk from mothers on macrobiotic and omnivorous diets.

The effect of alternative dietary habits and prolonged lactation on the nutrient and contaminant concentrations in human milk was studied. The study sample consisted of mothers on macrobiotic diets, containing little or no diary products and meat, at 2-3 months postpartum (n = 9) and 9-13 months postpartum (n = 12), and mothers on omnivorous diets at 2-3 months postpartum (n = 10). Protein and zinc concentrations in breast-milk from macrobiotic mothers decreased with stage of lactation. After adjustment for stage of lactation, milk from macrobiotic mothers contained less calcium, magnesium and saturated fatty acids C15:0-C20:0, and more polyunsaturated fatty acids. Observed tendencies for lower protein and fat and higher lactose concentrations in the macrobiotic group were not statistically significant. Concentrations of vitamin B12, HCB and polychlorinated biphenyls (PCB 118, PCB 138, PCB 153 and PCB 180) were lower in the macrobiotic group. After adjustment for confounding variables, meat and fish consumption, but not dairy products, contributed to vitamin B12 concentrations. Meat and diary products strongly contributed to breast-milk concentrations of dieldrin and PCBs, fish to PCB 118, and smoking to DDT and dieldrin. Our findings suggest that breast-milk contamination could be reduced by abstinence from smoking and a moderate intake of animal products. However, risk of nutritional deficiencies rules out complete avoidance of meat, fish or diary products. Quantitative research on the effects of a reduced consumption of animal products, as well as smoking, on breast-milk contamination is warranted.

The metabolic consequences of slow colonic transit.

Intestinal transit has a substantial influence on the enterohepatic circulation of bile acids and steroid hormones, on colonic pH, and on short chain fatty acid concentrations in the distal colon. Slow transit is likely to favor disease processes that are related to over-efficient enterohepatic recirculation and to lack of short chain fatty acid in the distal colon. These include gallstones, large bowel cancer, and possibly breast cancer. The best-documented influence of slow colonic transit is on bile acid metabolism. Slowing colonic transit increases deoxycholate and raises cholesterol saturation of bile, making gallstone formation more likely. In this review, we also examine the evidence that slow colonic transit may be important in the etiology of large bowel and breast cancer. There is a lack of data pertaining to the relationship between colonic transit and diseases such as colon and breast cancer. Should slow colonic transit prove to be a significant factor in the etiology of such diseases, then the health of the population might benefit from dietary and lifestyle changes that speed up intestinal transit.

Lignans and human health.

This review focuses on the possible role in human health of the consumption of lignan-rich foods. Most of the plant lignans in human foods are converted by the intestinal microflora in the upper part of the large bowel to enterolactone and enterodiol, called mammalian or enterolignans. The protective role of these compounds, particularly in chronic Western diseases, is discussed. Evidence suggests that fiber- and lignan-rich whole-grain cereals, beans, berries, nuts, and various seeds are the main protective foods. Many factors, in addition to diet, such as intestinal microflora, smoking, antibiotics, and obesity affect circulating lignan levels in the body. Lignan-rich diets may be beneficial, particularly if consumed for life. Experimental evidence in animals has shown clear anticarcinogenic effects of flaxseed or pure lignans in many types of cancer. Many epidemiological results are controversial, partly because the determinants of plasma enterolactone are very different in different countries. The source of the lignans seems to play a role because other factors in the food obviously participate in the protective effects. The results are promising, but much work is still needed in this area of medicine.