Effects of Epigallocatechin Gallate (EGCG) in Healthy, Young Adults

Cerebral Blood Flow, Cerebro-electrical Activity and Behavioural Effects of Epigallocatechin Gallate (EGCG) Administration in Healthy, Young Adults

Epigallocatechin gallate (EGCG) is the most abundant catechin (sometimes referred to as tea flavonoids) in green tea extract. A review by Nagle et al (2006) identifies that a large amount of research indicates EGCG (amongst other catechins) is responsible for most of the potential health benefits associated with green tea. EGCG is brain permeable (Nakagawa & Miyazawa, 1997), and it is considered to have neuroprotective and neurorescue effects including modulation of cell survival and cell cycle genes (Levites et al 2002).

Although there have been several human studies looking at the bioavailability of EGCG when administered in varying doses, there have been no studies that have specifically investigated the cognitive effects of this catechin in humans. Therefore, the purpose of this study is to assess the cerebral blood flow (using Near Infrared Spectroscopy), cerebro-electrical activity (EEG) and behavioural effects of EGCG. A randomised, double-blind, placebo-controlled, balanced crossover study will assess the effects of 135 mg and 270 mg pure EGCG in 24 healthy, young adults (18-35). Prior to the first active study day participants will attend a screening/training visit where relevant exclusion criteria will be assessed including any food sensitivities. They will also complete a caffeine consumption questionnaire in order to control for potential caffeine withdrawal effects as a result of restrictions of the study.

Study Overview

• Status: Completed
• Conditions: Cognitive Function; Mood
• Intervention / Treatment: Dietary supplement: EGCG; Dietary supplement: Placebo

• Study Type: Interventional
• Enrollment (Actual): 32
• Phase: Phase 4

Contacts and Locations

Study Locations

• United Kingdom
  • Newcastle upon Tyne, United Kingdom, NE1 8ST
    • Northumbria University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 33 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• healthy
• aged 18-35
• either caffeine consumers (consume more than 150mg caffeine per day) or non-consumers (consume less than 44mg caffeine per day).

Exclusion Criteria:

• smoke or consume any tobacco products
• not proficient in English language
• pregnant (or seeking to become pregnant)
• taking recreational, over the counter/prescription medication (including the contraceptive pill), and/or dietary/herbal supplements
• have food allergies or sensitivities
• have history of/current head trauma, learning difficulties , ADHD, migraines or any gastric problems

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Triple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: 135mg EGCG	Dietary supplement: EGCG; Acute oral administration of capsules containing either: 0mg, 135mg or 270mg. One dosage administered on each of three separate study days.; Other Names: Teavigo; Dietary supplement: Placebo; Pharmaceutical grade silica was utilized as placebo
Active Comparator: 270mg EGCG	Dietary supplement: EGCG; Acute oral administration of capsules containing either: 0mg, 135mg or 270mg. One dosage administered on each of three separate study days.; Other Names: Teavigo; Dietary supplement: Placebo; Pharmaceutical grade silica was utilized as placebo
Placebo Comparator: 0mg EGCG	Dietary supplement: EGCG; Acute oral administration of capsules containing either: 0mg, 135mg or 270mg. One dosage administered on each of three separate study days.; Other Names: Teavigo; Dietary supplement: Placebo; Pharmaceutical grade silica was utilized as placebo

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Modulation of Levels of Total Haemoglobin	This measure assessed changes in levels of total haemoglobin during the 42 minute post- dose task period. Levels are in μmol/L and represent change from baseline levels.	42 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants With Significant Modulation of Cognitive Performance	The cognitive performance of participants was assessed via a range of computerised, mentally demanding, executive function tasks: Serial 3s and 7s subtractions, oddball reaction time task, rapid visual information processing, stroop and simple reaction time.These tasks were completed at baseline and then again 45 minutes after treatment administration. Significant modulation was determined if participants' post dose scores were significantly higher than baseline.	42 minutes
Number of Participants With Significant Modulation of Mood.	Mood was assessed via computerised visual analogue scales at baseline and post- dose time points. Mood scores were calculated as change from baseline. And significant modulation was determined if baseline scores were significantly different to post dose.	42 minutes

Collaborators and Investigators

• Sponsor: Northumbria University
• Investigators: Principal Investigator: Crystal Haskell, Northumbria University

Study record dates

Study Major Dates

• Study Start: August 1, 2009
• Primary Completion (Actual): December 1, 2009
• Study Completion (Actual): December 1, 2009

Study Registration Dates

• First Submitted: September 21, 2009
• First Submitted That Met QC Criteria: September 21, 2009
• First Posted (Estimate): September 22, 2009

Study Record Updates

• Last Update Posted (Estimate): April 13, 2012
• Last Update Submitted That Met QC Criteria: March 20, 2012
• Last Verified: March 1, 2012

More Information

Terms related to this study

• Keywords: cognitive function; Electroencephalography; cerebral blood flow; Near Infrared spectroscopy; mood; Epigallocatechin Gallate; cerebro-electrical activity
• Other Study ID Numbers: 24Z1