Association Between Serum and Neuroimaging Measurements of the GABAergic System
NCT Number: NCT06464172
Status: NOT_YET_RECRUITING
Study Type: INTERVENTIONAL
Phases: NA
Conditions: GABAergic System
Interventions: OTHER: Acute Oral gamma-aminobutyric acid (Natural Health Product in Canada)|OTHER: Acute Placebo
Sponsor: Francois Corbin
Sex: ALL
Age: ADULT
Enrollment: 30
Study Design: Allocation: RANDOMIZED|Intervention Model: CROSSOVER|Masking: DOUBLE (PARTICIPANT, OUTCOMES_ASSESSOR)|Primary Purpose: BASIC_SCIENCE
Start Date: 2024-10-01
Completion Date: 2025-07-01

Summary:
The goal of this study is to better understand the relationship between peripheral and central nervous system measurements of the gamma-aminobutyric acid (GABA) system in otherwise healthy individuals. the main questions it aims to answer are:

1. Does GABA cross the blood-brain barrier?
2. Can peripheral measurements of the GABAergic system be used to study GABA in the brain?

Participants will receive oral GABA and Placebo and undergo blood draws, MRI scans and transcranial magnetic stimulation sessions.

Primary Outcome Measures: Impact of Acute GABA consumption on peripheral serum GABA concentrations, Serum GABA concentration will be measured before and after acute administration of GABA and placebo., Pre-GABA, 40 minutes after acute administration of GABA, Pre-Placebo, 40 minutes after acute administration of Placebo|Impact of Acute GABA consumption on short intracortical inhibition, TMS-derived measure of Intracortical inhibition: The degree of decrease of peak-to-peak motor evoked potential (MEP) amplitude induced by the administration of a conditioning stimulus (set at 70% of resting motor threshold) 2-4 ms before the test stimulus (stimulation intensity required to produce an MEP of 1 millivolt (mV), approximately 120% of resting motor threshold), Pre-GABA, 40 minutes after acute administration of GABA, Pre-Placebo, 40 minutes after acute administration of Placebo
Secondary Outcome Measures: Impact of Acute GABA consumption on short intracortical facilitation, Transcranial magnetic stimulation (TMS) -derived measure of Intracortical facilitation: The degree of increase of peak-to-peak motor evoked potential (MEP) amplitude induced by the administration of a conditioning stimulus (set at 80% of resting motor threshold) 12-24 ms before the test stimulus (stimulation intensity required to produce an MEP of 1 mV, approximately 120% of resting motor threshold)., Pre-GABA, 40 minutes after acute administration of GABA, Pre-Placebo, 40 minutes after acute administration of Placebo|Impact of Acute GABA consumption on GABA concentrations in the brain, Estimation of GABA concentrations in the brain from magnetic resonance spectroscopy, Pre-GABA, 40 minutes after acute administration of GABA, Pre-Placebo, 40 minutes after acute administration of Placebo|Impact of Acute GABA consumption on subjective alertness, Subjective alertness will be measured using the Biphasic Alcohol Alertness Scale (BAES). This scale which measures alertness and sedation and is comprised of 6 items, for each item participants rate how they feel from 1 (not at all) to 10 (extremely), Pre-GABA, 40 minutes after acute administration of GABA, Pre-Placebo, 40 minutes after acute administration of Placebo|Impact of Acute GABA consumption on objective alertness, Objective alertness will be measured using the psychomotor vigilance task (PVT). This computerised task measures alertness, participants will have to respond to visual cues that are presented at random intervals on the screen., Pre-GABA, 40 minutes after acute administration of GABA, Pre-Placebo, 40 minutes after acute administration of Placebo