Pharmacokinetic Study in Healthy Volunteers

This study investigates the evaluation of solanidine as an exogenous biomarker to phenotype CYP2D6-activity in humans. Participants will be classified by their CYP2D6 genotype into poor metabolizers (PM), low intermediate metabolizers (LIM), extensive metabolizers (EM) and ultra-rapid metabolizers (UM), forming four distinct study arms: Arm 1) Poor Metabolizers (PM) n=10 Arm 2) Low Intermediate Metabolizers (LIM) n=5 Arm 3) Extensive Metabolizers (EM) n=10 Arm 4) Ultra-rapid Metabolizers (UM) n=5 Participants will be given a standardized potato-rich meal, serving as the natural source of solanidine, and will be phenotyped for CYP2D6 activity with a single oral microdose of the probe drug yohimbine. The objectives of the study are as follows: 1. To evaluate the suitability of the SSDA/solanidine and m414/solanidine metabolic ratio as an exogenous biomarker to phenotype CYP2D6 activity in humans. 2. To characterize the postprandial plasma concentration profile of solanidine, its CYP2D6-dependent metabolites, and its parent molecules α-solanine and α-chaconine following a potato-rich meal.

This study investigates the differences in the kinetic parameters of fisetin in two cohorts of healthy volunteers: Cohort 1) volunteers aged 18-30 years (n = 40) Cohort 2) volunteers aged 65 years or older (n = 40) The purpose of this study is: 1. To describe the fisetin kinetics after a single dose oral administration in older age. 2. To compare the fisetin kinetics after a single dose oral administration in old and young age. FISEKIN-1 is designed as a four-arm study protocol. As well as two different age groups (18-30 years vs. 65 years and older), we want to compare fisetin kinetic parameters in fasted and fed condition: Arm 1) 500 mg fisetin (1x 5 capsule), fasted condition, cohort 1: young age Arm 2) 500 mg fisetin (1x 5 capsule), fasted condition, cohort 2: old age Arm 3) 500 mg fisetin (1x 5 capsule), fed condition, cohort 1: young age Arm 4) 500 mg fisetin (1x 5 capsule), fed condition, cohort 2: old age