None listed
Conditions
Brief summary
This study will aim to observe the short- and medium-term effects of a broccoli-enriched diet on the activity of CYP1A2, CYP2C19, CYP2C9, CYP2D6 and CYP3A4 in men of European and South Asian ancestry. It has been hypothesised that the broccoli-enriched diet will initially reduce the activity of these CYP-isoforms and increase their activity after 6 days of consumption.
Interventions
Broccoli-enriched diet (200 g of microwave-steamed broccoli with lunch and dinner) for 6 days (Days 3-8).
Two food diaries will be used to monitor adherence to the diet. Furthermore, phenethyl isothiocyanate (a broccoli constituent responsible for changes in CYP-enzyme activity) will be detected in participant plasma using an HPLC assay.
Five drugs will be administered as CYP-isoform-selective probes to assess enzyme activity. On study days, participants will receive 100 mg caffeine (CYP1A2),
Broccoli-enriched diet (200 g of microwave-steamed broccoli with lunch and dinner) for 6 days (Days 3-8). Two food diaries will be used to monitor adherence to the diet. Furthermore, phenethyl isothiocyanate (a broccoli constituent responsible for changes in CYP-enzyme activity) will be detected in participant plasma using an HPLC assay. Five drugs will be administered as CYP-isoform-selective probes to assess enzyme activity. On study days, participants will receive 100 mg caffeine (CYP1A2), 20 mg omeprazole (CYP2C19), 25 mg losartan (CYP2C9), 30 mg dextromethorphan (CYP2D6) and 2 mg midazolam (CYP3A4) in 5% dextrose solution. All medicines will be administered orally. The phenotyping cocktail will be administered before (Day 1), concomitantly with (Day 2) and 6 days after a broccoli-enriched diet (Day 9). Please note, the broccoli-enriched diet is administered for 6 days from Days 3-8 (inclusive) with a single 200 g amount concomitantly administered with the cocktail on Day 2.
Sponsors
University of Sydney
Study design
Allocation
Non-randomised trial
Intervention model
Single group
Primary purpose
Prevention
Masking
Open (masking not used)
Eligibility
Sex/Gender
Male
Age
18 Years to 55 Years
Healthy volunteers
Yes
Inclusion criteria
i. Male, aged 18-55 years ii. European or South Asian geographic ancestry iii. Non-smoker or ex-smoker that has abstained from smoking for at least 6 months iv. Ability to comply with the planned procedures and provide written informed consent which requires a level of English language competency to effectively understand the protocol and adequately meet the definition of informed consent v. Self-reported healthy with no reported or diagnosed acute or chronic health conditions vi. Access to a microwave with an appropriate cooking setting
Exclusion criteria
i. Known hypersensitivity or intolerance to any of the five drugs used in the study ii. History of clinical signs of hypotension, specifically fainting, light-headedness and/or a blood pressure lower than 80/60 mmHg iii. Female iv. Known food allergies or intolerances that limit participation in this study v. Oral antimicrobial use within the past 3 months vi. Body mass index (BMI) outside of 18.5-28.0 kg.m-2 vii. Currently taking or using any prescription, OTC, complementary or illicit medicines viii. Recently given blood or recently involved in another clinical study in the last 3 months
Outcome results
None listed