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Effects of Microencapsulated Sublingual Glycine (Bidicin) on Cognitive Performance in Healthy Men After an Acute Stressor

Not Applicable
Completed
Conditions
Healthy
Stress, Psychological
Cognitive Impairment
Interventions
Dietary Supplement: Placebo
Dietary Supplement: Microencapsulated Sublingual Glycine (MSG)
Registration Number
NCT03353441
Lead Sponsor
Daacro
Brief Summary

The aim of this study is to assess whether intake of Glycine (MSG) leads to an increase of cognitive performance after an acute stressor compared to placebo. One group will receive verum, one group placebo and one group will not receive any intervention. Cognitive testing will be performed in connection with the Trier Social Stress Test (TSST).

Detailed Description

Stress can enhance or impair memory performances depending on the timing of the stressor and the timing of the memory processes in relation to the stressor. If stress occurs directly before or during the retrieval of information, the performance is impaired. Decreased performances using an acute stressor were also observed for other domains of cognitive functioning like working memory, interference control, cognitive flexibility and attention tasks.

Glycine, the simplest of the amino acids, is an essential component of important biological molecules, a key substance in many metabolic reactions, the major inhibitory neurotransmitter in the spinal cord and brain stem, and an anti-inflammatory, cytoprotective, and immune modulating substance. Studies have found positive effects of Glycine on episodic memory retrieval and in a word retrieval task.

To assess the effect of Glycine (MSG) on cognitive performance after an acute stressor, subjects perform baseline cognitive testing before intake of investigational products (Glycine (MSG), placebo or nothing) and participation in a stress test (Trier Social Stress Test - TSST). After the TSST stress-induced changes in cognitive performance are assessed. A second treatment intake takes place between the first and the remaining cognitive tests.

Recruitment & Eligibility

Status
COMPLETED
Sex
Male
Target Recruitment
90
Inclusion Criteria
  • subject signs the informed consent to participate in the study
  • normally stressed subjects as verified by the TICS questionnaire with scores >3 and <37
Exclusion Criteria
  • smoker
  • any known allergies to the test substances
  • lactose intolerance
  • any known addiction to drugs and/or alcohol
  • hyper- or hypotension (except for those whose blood pressure is stable using medication for more than 3 months)
  • known hyper- or hypothyroidism unless treated and under control (stable for more than 3 months)
  • any known current/acute or chronic physical or psychological diseases besides minor medical conditions (e.g. seasonal allergies)
  • intake of any medication which may affect the cognitive performance (e.g. psychotropics, sedating or stimulating medication)
  • any color vision impairment (e.g. red-green deficiency)
  • intake of dietary supplements or homoeopathic remedies during 2 weeks before V1 or during the study conduction
  • consumption of alcohol during 2 days before V1 or during the study conduction
  • excessive caffeine consumption (>400 mg caffeine/day or >= 4 cups of caffeinated coffee)
  • on a strict diet or practicing sport, extensively
  • attending an exam one week before and after the study participation
  • subjects having previously participated in the TSST
  • employee of the sponsor or Contract Research Organisation (CRO)
  • Investigator doubts truthfulness of self-reported health information
  • not suitable because of limited verbal and cognitive abilities

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
PlaceboPlaceboLactose: 1 tablet prior to TSST; 1 tablet after the TSST
Glycine (MSG)Microencapsulated Sublingual Glycine (MSG)Microencapsulated Sublingual Glycine (MSG): 1 tablet prior to TSST; 1 tablet after the TSST
Primary Outcome Measures
NameTimeMethod
Delayed memory performance after the TSST (correct words)20 minutes after second product intake

Efficacy of the intake of Glycine (MSG) on performance in the Verbal Learning and Memory Test (VLMT) delayed recall task (number of correct words) compared to placebo and control group

Secondary Outcome Measures
NameTimeMethod
Immediate memory performance before and after the TSST44 minutes before, 13 and 48 minutes after first product intake

Efficacy of the intake of Glycine (MSG) on Performance in the Verbal Learning and Memory Test (VLMT) immediate recall task (number of correct words, decreased number of perseverations and wrong words) compared to placebo and control group

VAS stress20 minutes, 37 minutes and 46 minutes after first product intake

Efficacy of the intake of Glycine (MSG) on subjective evaluation of acute stress compared to placebo and control group measured on a Visual Analogue Scale (VAS). The VAS is a 10cm bipolar visual scale ranging from "not at all" to "highly". VAS scores are obtained by using a ruler and measuring the position of the participant's mark with millimeter precision. To control for possible variations due to printing, the total length of the line is also measured and percentage scores for each subject are computed. Percentage scores range from 0-100.

VAS sleepiness20 minutes, 37 minutes and 46 minutes after first product intake

Efficacy of the intake of Glycine (MSG) on subjective evaluation of acute sleepiness compared to placebo and control group measured on a Visual Analogue Scale (VAS). The VAS is a 10cm bipolar visual scale ranging from "not at all" to "highly". VAS scores are obtained by using a ruler and measuring the position of the participant's mark with millimeter precision. To control for possible variations due to printing, the total length of the line is also measured and percentage scores for each subject are computed. Percentage scores range from 0-100.

VAS insecurity20 minutes, 37 minutes and 46 minutes after first product intake

Efficacy of the intake of Glycine (MSG) on subjective evaluation of acute insecurity compared to placebo and control group measured on a Visual Analogue Scale (VAS). The VAS is a 10cm bipolar visual scale ranging from "not at all" to "highly". VAS scores are obtained by using a ruler and measuring the position of the participant's mark with millimeter precision. To control for possible variations due to printing, the total length of the line is also measured and percentage scores for each subject are computed. Percentage scores range from 0-100.

VAS tension20 minutes, 37 minutes and 46 minutes after first product intake

Efficacy of the intake of Glycine (MSG) on subjective evaluation of acute tension compared to placebo and control group measured on a Visual Analogue Scale (VAS). The VAS is a 10cm bipolar visual scale ranging from "not at all" to "highly". VAS scores are obtained by using a ruler and measuring the position of the participant's mark with millimeter precision. To control for possible variations due to printing, the total length of the line is also measured and percentage scores for each subject are computed. Percentage scores range from 0-100.

VAS anxiety20 minutes, 37 minutes and 46 minutes after first product intake

Efficacy of the intake of Glycine (MSG) on subjective evaluation of acute anxiety compared to placebo and control group measured on a Visual Analogue Scale (VAS). The VAS is a 10cm bipolar visual scale ranging from "not at all" to "highly". VAS scores are obtained by using a ruler and measuring the position of the participant's mark with millimeter precision. To control for possible variations due to printing, the total length of the line is also measured and percentage scores for each subject are computed. Percentage scores range from 0-100.

Cognitive performance before and after the TSST (Stroop)10 minutes before first product intake and 23 minutes after second product intake

Efficacy of the intake of Glycine (MSG) on performance in the Stroop test (speed and accuracy) compared to placebo and control group

Delayed memory performance before and during the TSST15 minutes before and 42 minutes after first product intake

Efficacy of the intake of Glycine (MSG) on performance in the Verbal Learning and Memory Test (VLMT) delayed recall task (number of correct words, number of perseverations and wrong words) compared to placebo and control group

Delayed memory performance after the TSST (perseverations, wrong words)20 minutes after second product intake

Efficacy of the intake of Glycine (MSG) on performance in the Verbal Learning and Memory Test (VLMT) delayed recall task (decreased number of perseverations and wrong words) compared to placebo and control group

Heart rateContinous measurement starting 10 minutes after first product intake and ending 10 minutes after second product intake

Efficacy of the intake of Glycine (MSG) on heart rate in response to the TSST compared to placebo and control group

VAS lack of energy20 minutes, 37 minutes and 46 minutes after first product intake

Efficacy of the intake of Glycine (MSG) on subjective evaluation of acute lack of energy compared to placebo and control group measured on a Visual Analogue Scale (VAS). The VAS is a 10cm bipolar visual scale ranging from "not at all" to "highly". VAS scores are obtained by using a ruler and measuring the position of the participant's mark with millimeter precision. To control for possible variations due to printing, the total length of the line is also measured and percentage scores for each subject are computed. Percentage scores range from 0-100.

STAI-state20 minutes and 46 minutes after first product intake

Efficacy of the intake of Glycine (MSG) on state anxiety as measured by the State Trait Anxiety Inventory (STAI) compared to placebo and control group. The STAI-state measures anxiety as a temporary emotional state and comprises 20 items. Answers are given on a four-point rating scale ranging from 1 = "not at all" to 4 = "very true". Some STAI questions relate to the absence of anxiety, and are reversely scored. For analysis of the STAI-scale, items are combined in one scale, which then informs about state anxiety. The score range is 20-80; higher scores indicate more anxiety.

Cognitive performance before and after the TSST (CogTrack)40 minutes before first product intake, immediately after second product intake

Efficacy of the intake of Glycine (MSG) on performance in attention, working memory, learning and recognition tasks of CogTrack compared to placebo and control group

Salivary Cortisol45, 10 minutes before first product intake, 28, 46, 55 minutes after first product intake, 10, 20, 35 and 50 minutes after second product intake

Efficacy of the intake of Glycine (MSG) on salivary cortisol raw values in response to the TSST compared to placebo and control group

Systolic and diastolic blood pressure25 minutes and 46 minutes after first product intake

Efficacy of the intake of Glycine (MSG) on blood pressure in response to the TSST compared to placebo and control group

Trial Locations

Locations (1)

daacro GmbH & Co. KG

🇩🇪

Trier, Rhineland-Palatinate, Germany

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