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Completed

NCT Number: NCT03353441

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

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).

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Key information

Conditions

Healthy Behavior Behavioral Symptoms Cognition Disorders Cognitive Dysfunction Cognitive Impairment Mental Disorders Neurocognitive Disorders Stress, Psychological

Age range

18 year–40 year

Sex eligibility

Male

Study type

Interventional

Phase

Not applicable

Primary location

daacro GmbH & Co. KG

Trier, Rhineland-Palatinate, 54296, Germany

About this study

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.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

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

Treatment and study plan

Microencapsulated Sublingual Glycine (MSG)

Dietary Supplement

Glycine (MSG) tablet

Other names: Bidicin

Placebo

Dietary Supplement

Lactose tablet manufactured to mimic Glycine (MSG) tablet

Primary outcomes

  1. Delayed memory performance after the TSST (correct words)

    Time frame: 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 outcomes

  1. Delayed memory performance before and during the TSST

    Time frame: 15 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

  2. Immediate memory performance before and after the TSST

    Time frame: 44 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

  3. VAS stress

    Time frame: 20 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.

  4. VAS anxiety

    Time frame: 20 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.

  5. VAS insecurity

    Time frame: 20 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.

  6. VAS sleepiness

    Time frame: 20 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.

  7. VAS tension

    Time frame: 20 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.

  8. VAS lack of energy

    Time frame: 20 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.

  9. STAI-state

    Time frame: 20 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.

  10. Systolic and diastolic blood pressure

    Time frame: 25 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

  11. Delayed memory performance after the TSST (perseverations, wrong words)

    Time frame: 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

  12. Cognitive performance before and after the TSST (Stroop)

    Time frame: 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

  13. Cognitive performance before and after the TSST (CogTrack)

    Time frame: 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

  14. Heart rate

    Time frame: Continous 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

  15. Salivary Cortisol

    Time frame: 45, 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

Other outcomes

  1. TICS

    Time frame: Baseline

    Do Trier Inventory for Chronic Stress (TICS) scores differ between groups? The TICS includes 57 items. Stress chronicity is measured by the frequency of stressful events perceived retrospectively within the last 3 months. Answers are given on a five-point rating scale, where 0 resembles "never" and 4 "very often". For analysis the questionnaire items are assigned to 10 scales: Work overload (range 0-32), Social overload (0-24), Pressure to succeed (0-36), Work dissatisfaction (0-32), excessive demands at work (0-24), Lack of social recognition (0-16), Social stress (0-24), Social isolation (0-24) and Chronic worrying (0-16); the last scale presents a Screening scale for chronic stress (0-48). Scores are obtained by summing up the values of the scale specific questionnaire items.

  2. STAI-trait

    Time frame: Baseline

    Do State Trait Anxiety Inventory (STAI) trait scores differ between groups? The STAI-trait measures anxiety as a personality trait and comprises 20 items. Answers are given on a four-point rating scale ranging from 1 = "almost never" to 4 = "almost always". 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 trait anxiety. The score range is 20-80; higher scores indicate more anxiety.

  3. Mental arithmetic performance during the TSST

    Time frame: 37.5 minutes after first product intake

    Efficacy of the intake of Glycine (MSG) on arithmetic performance compared to placebo and control group. One part of the Trier Social Stress Test (TSST) is a mental arithmetic task. The subject is asked to stepwise subtract 17 from 2023 as quickly and correctly as possible. Performance will be measured by counting how many numbers the subject enumerates and how many times the subject has to restart. Furthermore, the lowest correct number and the shortest run will be recorded.

  4. eCB levels

    Time frame: 45, 10 minutes before first product intake, 28, 46, 55 minutes after first product intake, 10, 20, 35 and 50 minutes after second product intake

    Exploration of endocannabinoid levels (eCB)

  5. Blood Glucose levels

    Time frame: 75 minutes before first product intake, 25 and 46 minutes after first product intake

    Exploration of blood glucose levels

Sponsors and collaborators

Lead sponsor

Daacro

Network

Collaborators

  • OOO MNPK BIOTIKI

Registry information

Official study title

Effects of Microencapsulated Sublingual Glycine (Bidicin) on Cognitive Performance in Healthy Men After an Acute Stressor - a Randomized, Partly Double-blind Placebo-controlled Clinical Trial

Important dates

Study start
2017
Primary completion
2018
Study completion
2018
First posted
Nov 27, 2017
Registry last updated
Jul 26, 2018

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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