Impact of Food Intake on Berberine Kinetics
The influence of genetic variants of the CYP2D6 enzyme and the Organic Cation Transporter 1 on the kinetics of berberine (BERKI-1) has recently been studied. A significant sex difference was observed. These results lead to the BERKI-2 study, investigating the influence of the female hormonal cycle on berberine kinetics. In this study, women took a single berberine dose once in the first and once in the second half of their menstrual cycle, men served as a control group ingesting a single berberine dose. Contrary to our expectations, the previously observed sex difference could not be confirmed.

In both BERKI-1 and 2 studies, the plasma concentration curve exhibited two peaks. The first after about 2-3 h, and the second after approximately 5 h of berberine intake. All participants took a single dose of Berberine under fasting conditions in the morning and 4 h after berberine intake, they ate a meal. Shortly after meal intake, the plasma concentration curve peaked again BERKI-3 will investigate the impact of food intake on berberine bioavailability and the kinetic properties. Given the suspected influence of berberine on glycemic control, we will also measure insulin and glucose after the meal at noon.

As in BERKI-1 and 2, time dependent blood and urine samples will be collected after a single berberine dose. One By measuring berberine metabolites by Liquid Chromatography and Mass-spec One dose will be taken in the fasted condition and the other two after a light or high caloric meal, respectively.

24 heathy volunteers with an equal ratio of man and women will be enrolled.
- EligibilityCriteria: Inclusion Criteria:  wildtype genotypes for CYP2D6 and OCT1 understands the study purpose and design contractually capable and provides signed informed consent form healthy condition or mild and/or well treated forms of allergies, asthma, hypertension and orthopedic diseases  Exclusion Criteria:  BMI ≤18,5kg/m2 and ≥29,9 kg/m2 only in women: known pregnancy or lactation period only in women: positive pregnancy test at screening or any other study visit danemia: Hb < 13 g/dl (8,07 mmol/l) in men or < 12 g/dl (7,45 mmol/l) in women elevated liver function tests (ALAT, ASAT, yGT, Bilirubin > 2xULN) reduced renal function (eGFRMDRD < 60ml/min/1,7m2) currently mentally unstable use of recreational drugs more than twice a week poor venous conditions that make it impossible to place a peripheral venous catheter and regularly draw blood through it - HealthyVolunteers: Accepts Healthy Volunteers - Gender: All - MinimumAge: 18 Years - MaximumAge: 40 Years - StdAgeList: Adult