Neural Effects of Green Tea Extract on Dorsolateral Prefrontal Cortex

Exploratory Behavior Clinical Trial

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01615289
• Other study ID #: EKBB 32/09
• Status: Completed
• Phase: N/A
• First received: June 5, 2012
• Last updated: June 7, 2012
• Start date: July 2010
• Est. completion date: January 2012

Study information

• Verified date: June 2012
• Source: University Hospital, Basel, Switzerland
• Contact: n/a
• Is FDA regulated: No
• Health authority: Switzerland: Ethikkommission
• Study type: Interventional

Clinical Trial Summary

Green tea is being recognized as a beverage with potential benefits for human health and on cognitive function. In vitro and in vivo studies provide preliminary evidence that green tea intake may play a positive role in improving effects on cognitive functions. The investigators aim to examine the neural effects of green tea extract on brain activation in humans.

Description:

As functional neuroimaging provides a means of examining how green tea extract acts on the brain, we used functional magnetic resonance imaging (fMRI) to study healthy volunteers while they performed a working memory task following intra-gastric administration of either 250 ml or 500 ml Rivella green® (RG), a milk whey based green tea extract containing soft drink, or Rivella blue® (RB), a milk whey based soft drink without green tea extract as sham condition in a double-blind, controlled design. Based on the literature on pharmacological and behavioural effects of green tea, we hypothesized - a priori - that green tea extract would subtly modulate the engagement of the dorsolateral prefrontal cortex (DLPFC), a brain region critically involved in many cognitive functions such as working memory processing.

A double-blind, controlled, within-subject study with counterbalanced order of substance administration using an established protocol (6-8) was conducted over 4 sessions (250 ml or 500 ml Rivella green® (including green tea extract; RG), 250 or 500 ml Rivella blue® (RB). Each participant was scanned four times with a one-week interval between scans. The order of substance administration across sessions was counterbalanced across subjects, such that equal numbers followed each substance sequence.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 12
• Est. completion date: January 2012
• Est. primary completion date: January 2011
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Male
• Age group: 18 Years to 35 Years

Eligibility

Inclusion Criteria:

• right-handed healthy males, no drugs, non-smoking

Exclusion Criteria:

• drug abuse, smoker, left-handed

Study Design

Allocation: Randomized, Endpoint Classification: Pharmacodynamics Study, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Prevention

Related Conditions & MeSH terms

• Exploratory Behavior

Intervention

Dietary Supplement:
• Single intragastric instillation of 250 ml green tea extract
Intragastric instillation by feeding tube
• Single intragastric instillation of 500 ml green tea extract
Intragastric instillation by feeding tube
• Single intragastric instillation of 250 ml control solution
Intragastric instillation by feeding tube
• Single intragastric instillation of 500 ml control solution
Intragastric instillation by feeding tube

Locations

Country	Name	City	State
Switzerland	University Hospital	Basel

Sponsors (1)

Lead Sponsor	Collaborator
University Hospital, Basel, Switzerland

Country where clinical trial is conducted

Switzerland, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Functional magnetic resonance imaging (fMRI) in healthy volunteers while they performed a working memory task	Whole brain analysis with a cluster-level threshold was followed by an a priori defined region of interest analysis of the dorsolateral prefrontal cortex including a cluster-level threshold and family-wise error adjustment for multiple comparisons.	0 and 45 min	No