***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Heavy exercise causes gut symptoms and , in extreme cases , " heat stroke " partially due to increased intestinal permeability of luminal toxins . We examined  bovine colostrum  , a natural source of growth factors , as a potential moderator of such effects . Twelve volunteers completed a double-blind , placebo-controlled , crossover protocol  ( 14 days colostrum/placebo ) prior to st and ardized exercise . Gut permeability utilized 5 h urinary lactulose-to-rhamnose ratios . In vitro studies ( T84 , HT29 , NCM460 human colon cell lines ) examined colostrum effects on temperature-induced apoptosis ( active caspase-3 and 9 , Baxα , Bcl-2 ) , heat shock protein 70 ( HSP70 ) expression and epithelial electrical resistance . In both study arms , exercise  increased blood lactate , heart rate , core temperature ( mean 1.4 ° C rise ) by similar amounts . Gut hormone profiles were similar in both arms although GLP-1 levels rose following exercise in the placebo but not the colostrum arm ( P = 0.026 ) . Intestinal permeability in the placebo arm increased 2.5-fold following exercise ( 0.38 ± 0.012 baseline , to 0.92 ± 0.014 , P < 0.01 ) , whereas colostrum truncated rise by 80 % ( 0.38 ± 0.012 baseline to 0.49 ± 0.017 ) following exercise . In vitro apoptosis increased by 47 - 65 % in response to increasing temperature by 2 ° C . This effect was truncated by 60 % if colostrum was present ( all P < 0.01 ) . Similar results were obtained examining epithelial resistance ( colostrum truncated temperature-induced fall in resistance by 64 % , P < 0.01 ) . Colostrum increased HSP70 expression at both 37 and 39 ° C ( P < 0.001 ) and was truncated by addition of an EGF receptor-neutralizing antibody . Temperature-induced increase in Baxα and reduction in Bcl-2 was partially reversed by presence of colostrum . Colostrum may have value in enhancing athletic performance and preventing heat stroke This study investigated plasma lipopolysaccharides ( LPS ) concentration and intestinal permeability after 60-min run at 70 % maximum oxygen uptake ( VO2max ) in hot [ 33 ° C , 50 % relative humidity ( rH ) ] and cool ( 22 ° C , 62 % rH ) conditions . Fifteen volunteers gave their informed consent to participate in this study . Their venous blood sample s were taken before , after , 2 and 5 h after exercise in each of the conditions . The order of the two environmental conditions in which they exercised in was r and omised and counterbalanced . Plasma LPS concentration increased by an average of 54.0 % ( 95 % confidence interval : 30.7 , 75.1 % ) after exercising in the hot trial but no significant changes were observed in cool trial , where mean plasma LPS concentration was 12.0 ± 6.4 pg mL−1 ( before ) , 10.9 ± 5.4 pg mL−1 ( after ) , 10.7 ± 6.0 pg mL−1 ( 2 h after ) and 10.6 ± 5.7 pg mL−1 ( 5 h after ) . Median ( range ) plasma claudin-3 ( CLDN3 ) concentration was significantly higher after exercise ( hot : 8.2 [ 1.0–13.0 ] ng mL−1 and cool : 7.6 [ 0.6–13.4 ] ng mL−1 ) as compared to before exercise ( hot : 6.6 [ 0.7–11.8 ] ng mL−1 and cool : 6.7 [ 0.8–12.6 ] ng mL−1 ) ( p < 0.05 ) , but there is no significant difference observed between trials ( p > 0.05 ) . Changes in intestinal permeability are only affected by exercise while exercise-induced endotoxemia is affected by environmental conditions . This study , thus , highlights that an increase in intestinal permeability is not sufficient to trigger exercise-induced endotoxemia , suggesting that post-LPS translocation events may have a greater impact in its occurrence The purpose of this study was to determine whether aspirin ( A ) ingestion combined with prolonged exercise increases gastrointestinal permeability and whether consumption of a carbohydrate-containing ( CHO ) or a CHO + glutamine-containing ( CHO+G ) beverage would reduce this effect . Seventeen subjects completed six experiments . They ingested A ( 1,300 mg ) or placebo ( P ) pills the evening before and before running 60 min at 70 % maximal oxygen uptake . Also , before running they ingested a solution containing 5 g lactulose ( L ) , 5 g sucrose ( S ) , and 2 g rhamnose ( R ) . During each trial , either a 6 % CHO beverage , a 6 % CHO+G ( 0.6 % ; 41 mM ) beverage , or a water placebo ( WP ) was consumed . For 4 h after a run , all urine was collected to measure urinary excretion of L , R , and S. S excretion ( percentage of dose ingested ; measure of gastroduodenal permeability ) was significantly greater ( P < 0.05 ) during the A trial while the subjects drank the WP compared with all other trials . Administration of A also significantly increased L/R ( measure of intestinal permeability ) for the CHO and WP trials compared with all P trials . Ingestion the CHO or CHO+G beverages significantly reduced S excretion and L excretion when A was administered , but it did not reduce L/R. These results indicate that gastroduodenal and intestinal permeability increase after A ingestion during prolonged running and that ingestion of a CHO beverage attenuates the gastroduodenal effect but not the intestinal effect . Furthermore , addition of G to the CHO beverage provided no additional benefit in reducing gastroduodenal or intestinal permeability Thermotolerance and heat acclimation are key adaptation processes that have been hitherto viewed as separate phenomena . Here , we provide evidence that these processes may share a common basis , as both may potentially be governed by the heat shock response . We evaluated the effects of a heat shock response-inhibitor ( quercetin ; 2,000 mg/day ) on established markers of thermotolerance [ gastrointestinal barrier permeability , plasma TNF-α , IL-6 , and IL-10 concentrations , and leukocyte heat shock protein 70 ( HSP70 ) content ] . Heat acclimation reduced body temperatures , heart rate , and physiological strain during exercise/heat stress ) in male subjects ( n = 8) completing a 7-day heat acclimation protocol . These same subjects completed an identical protocol under placebo supplementation ( placebo )  . Gastrointestinal barrier permeability and TNF-α were increased on the 1st day of exercise/heat stress in quercetin ; no differences in these variables were reported in placebo .  Exercise HSP70 responses were increased , and plasma cytokines ( IL-6 , IL-10 ) were decreased on the 7th day of heat acclimation in placebo ; with concomitant reductions in exercise body temperatures , heart rate , and physiological strain . In contrast , gastrointestinal barrier permeability remained elevated , HSP70 was not increased , and IL-6 , IL-10 , and exercise body temperatures were not reduced on the 7th day of heat acclimation in quercetin . While exercise heart rate and physiological strain were reduced in quercetin , this occurred later in exercise than with placebo . Consistent with the concept that thermotolerance and heat acclimation are related through the heat shock response , repeated exercise/heat stress increases cytoprotective HSP70 and reduces circulating cytokines , contributing to reductions in cellular and systemic markers of heat strain . Exercising under a heat shock response-inhibitor prevents both cellular and systemic heat adaptations BACKGROUND Glutamine ( GLN ) is the preferred fuel for enterocytes , and GLN supplementation is critical during stressful conditions . The aim of this study was to evaluate the effect of GLN on intestinal barrier permeability and bacterial translocation in a murine experimental model . METHODS Swiss male mice ( 25 - 30 g ) were r and omized into 3 groups : ( 1 ) sham group ; ( 2 ) intestinal obstruction ( IO ) group ; ( 3 ) IO and GLN ( 500 mg/kg/d ) group . Two different experiments were carried out to assess intestinal permeability and bacterial translocation . In the first experiment , the animals were divided into the 3 groups described above and received diethylenetriamine pentaacetate radiolabeled with technetium ( (99m)Tc ) on the eighth day . At different time points after intestinal obstruction , blood was collected to determine radioactivity . The animals were killed , and the small intestine was removed for histological analyses . In the bacterial translocation study , on the eighth day all groups received Escherichia coli labeled with (99m)Tc . After 90 minutes , the animals underwent intestinal obstruction and were killed 18 hours later . Blood , mesenteric lymph nodes , liver , spleen , and lungs were removed to determine radioactivity . Statistical significance was considered when P < or = .05 . RESULTS The levels of intestinal permeability and bacterial translocation were higher in the IO group than in the sham and GLN groups ( P < .05 ) . GLN decreased intestinal permeability and bacterial translocation to physiologic levels in the treated animals and preserved intestinal barrier integrity . CONCLUSIONS GLN had a positive impact on the intestinal barrier by reducing permeability and bacterial translocation to physiologic levels and preserving mucosal integrity Purpose This study aim ed to investigate the effects of multi-strain probiotics supplementation on gastrointestinal permeability , systemic markers of inflammation and running performance when exercising in the heat . Methods Ten male runners were r and omized to 4 weeks of daily supplementation with a probiotics capsule ( 45 billion CFU of Lactobacillus , Bifidobacterium and Streptococcus strains ) or placebo , separated by a washout period ( double-blind , cross-over trial ) . After each treatment , the runners exercised to fatigue at 80 % of their ventilatory threshold at 35 ° C and 40 % humidity . To assess gastrointestinal permeability , runners ingested lactulose and rhamnose before exercise and post-exercise urine was collected to measure sugar concentrations . Venous blood sample s were collected before , immediately after and 1 h after exercise , and core temperature was monitored during exercise . Results Probiotics supplementation significantly increased run time to fatigue ( min : s 37:44 ± 2:42 versus 33:00 ± 2:27 ; P = 0.03 , d = 0.54 ) . Average core temperature during exercise was similar between trials ( probiotic 38.1 ± 0.2 ° C , placebo 38.1 ± 0.1 ° C ; P = 0.77 , d = 0.13 ) . Serum lipopolysaccharide concentration increased post-exercise ( P < 0.001 ) , while there was a moderate to large reduction in pre-exercise ( d = 0.70 ) and post-exercise ( d = 1.24 ) concentration following probiotics supplementation . Plasma concentrations of IL-6 , IL-10 and IL-1ra increased after exercise ( P < 0.01 ) , but there was no significant difference between trials ( P > 0.05 ) . There was a small to moderate reduction ( d = 0.35 ) in urine lactulose : rhamnose and a small reduction ( d = 0.25 ) in symptoms of gastrointestinal discomfort following probiotics supplementation ( both P = 0.25 ) . Conclusion Four weeks of supplementation with a multi-strain probiotic increased running time to fatigue in the heat . Further studies are required to eluci date the exact mechanisms for this performance benefit Non-steroidal anti-inflammatory drugs ( NSAIDs ) are effective analgesics but cause gastrointestinal injury . Present prophylactic measures are suboptimal and novel therapies are required . Bovine colostrum is a cheap , readily available source of growth factors , which reduces gastrointestinal injury in rats and mice . We therefore examined whether spray-dried , defatted colostrum could reduce the rise in gut permeability ( a non-invasive marker of intestinal injury ) caused by NSAIDs in volunteers and patients taking NSAIDs for clinical reasons . Healthy male volunteers ( n=7 ) participated in a r and omized crossover trial comparing changes in gut permeability ( lactulose/rhamnose ratios ) before and after 5 days of 50 mg of indomethacin three times daily ( tds ) per oral with colostrum ( 125 ml , tds ) or whey protein ( control ) co-administration . A second study examined the effect of colostral and control solutions ( 125 ml , tds for 7 days ) on gut permeability in patients ( n=15 ) taking a substantial , regular dose of an NSAID for clinical reasons . For both studies , there was a 2 week washout period between treatment arms . In volunteers , indomethacin caused a 3-fold increase in gut permeability in the control arm ( 
    Output:
    
Conclusion The magnitude of exercise-induced hyperthermia is directly associated with the increase in intestinal permeability