Effect of Tea Consumption on Steroid Profile in Healthy Volunteers

Effect of Tea Consumption on Steroid Profile in Healthy Volunteers. Pilot Study

Open label phase I clinical trial in healthy volunteers designed to assess changes on steroid profile after green tea consumption.

Study Overview

• Status: Completed
• Conditions: Healthy Volunteers; Doping in Sports
• Intervention / Treatment: Dietary supplement: Green tea

Detailed Description

Anabolic androgenic steroids are included in the list of banned substances in sports by the World Anti-Doping Agency (WADA) because of its ability to improve the performance of athletes.

Testosterone glucuronization by UGT2B17 isoenzyme (Uridine Diphosphate Glucuronyltransferase 2B17) is inhibited in vitro by green tea flavonols like epicatechin, epigallocatechin gallate (EGCG) and catechin gallate.

Therefore a diet rich in green tea could interfere in androgens' glucuronization and cause a change on the steroid profile of the athletes that could be considered a false positive.

A clinical trial designed to assess changes on steroid profile in healthy volunteers after green tea consumption will be conducted. Subjects with different UGT2B17 genotype will be recruited (10 of each type: ins/ins, ins/del, del/del) to study if the genotype can modulate the results obtained.

Urine samples obtained before and during 7 days of green tea consumption will be used to compare steroid profile. Blood samples will be also collected to assess EGCG pharmacokinetics.

• Study Type: Interventional
• Enrollment (Actual): 29
• Phase: Phase 1

Contacts and Locations

Study Locations

• Spain
  • Barcelona, Spain, 08003
    • Parc de Salut Mar-IMIM

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 50 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Male

Description

Inclusion Criteria:

• Understand and accept the study's procedures and sign an informed consent form
• Body mass index (BMI=weight/heigth2) between 19 and 27 kg/m2, weight between 50 and 100 kg.
• No evidence of somatic or psychiatric disorders as per past medical history and physical examination
• EKG, blood and urine tests taken before entry into the study within the normal range. Minor and transient abnormalities may be acceptable if, according to the Principal Investigator's criterion and the state of the art, they are felt to have no clinical relevance, entail no danger to the participant, and don't interfere with the product's assessment. These abnormalities and their non-relevance must be specifically justified in writing)

Exclusion Criteria:

• Evidence of a preexisting condition (including gastrointestinal, liver, or kidney disorders) that may alter the absorption, distribution, metabolism or excretion of the drug or symptoms suggestive of drug-induced gastrointestinal irritation
• Previous psychiatric disorders, alcoholism, abuse of prescription drugs or illegal substances or regular consumption of psychoactive drugs
• Having donated blood or having participated in this same study in the preceding 8 weeks, or having participated in any clinical trial with drugs in the preceding 12 weeks
• Having had any somatic disease or having undergone major surgery in the 3 months prior to inclusion in the trial
• Individuals intolerant or having experienced a severe adverse reaction to green tea or caffeine
• Having regularly taken medication in the month before the trial, except for vitamins, herb-based remedies, dietary supplements that if, according to the Principal Investigator or his appointed collaborators' opinion, they pose no threat to the subjects and they won't interfere with the study's objectives. Single doses of symptomatic drugs taken during the week before the experimental session will not constitute an exclusion criterion if it can be assumed that it has been completely eliminated on the day of the experimental session
• Smokers of >10 cigarettes/day
• Consumption of >40 g/day of alcohol
• Daily consumption of less than one xanthine-containing beverages per day
• Hepatitis B, hepatitis C or human immunodeficiency virus-positive individuals
• Vegetarian subjects or with aberrant diets

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Green tea; Green tea consumption along 7 days.

Dietary supplement: Green tea; Lipton pure green tea, 5 teas on the first 6 days, and 9 teas on the day 7. Teas will be ingested at 08:00 am, 10:30 am, 13:00 pm, 15:30 pm, 18:00 pm days 1-6, and 08:00 am (*), 10:30 am, 13:00 pm (*), 15:30 pm, 18:00 pm (*), 20:30 pm on day 7. One bag of tea will be used to prepare the beverages with exception of some beverages on day 7 that will be prepared with two bags (*).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Steroid profile in urine	24 hours urine will be collected.	From 3 days before consumption (day -3,-2,-1) till day 8 (day 1-8) after consumption

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Epigallocatechin gallate (EGCG) blood concentrations	One sample before tea administration (day -1) and 3 samples on day 7 (before, 1hour and 2 hours after first tea on day 7).	Baseline and day 7
Serious and non serious adverse events	Adverse events reported by subjects and interrogated by investigators will be collected.	From inclusion till day 9 (final visit)
UGT2B17 Genotype	Sample for pharmacogenetics will be obtained before tea administration	Baseline

Collaborators and Investigators

• Sponsor: Parc de Salut Mar
• Collaborators: World Anti-Doping Agency
• Investigators: Study Director: Rosa Ventura, PhD, World Anti-doping Agency

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2016
• Primary Completion (Actual): February 14, 2017
• Study Completion (Actual): February 14, 2017

Study Registration Dates

• First Submitted: May 18, 2016
• First Submitted That Met QC Criteria: May 19, 2016
• First Posted (Estimate): May 20, 2016

Study Record Updates

• Last Update Posted (Actual): July 28, 2017
• Last Update Submitted That Met QC Criteria: July 26, 2017
• Last Verified: July 1, 2017

More Information

Terms related to this study

• Keywords: green tea; steroid profile
• Other Study ID Numbers: IMIMFTCL/EGCG/3

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No