The Effect of Supplementation With Lactobacillus Helveticus R0052 and Bifidobacterium Longum R0175 Combination Probiotic on Mental Health Indices and Oral Microbiota Status in Healthy Volunteers Facing a Stressful Event
Overview
- Phase
- Not Applicable
- Intervention
- Not specified
- Conditions
- Healthy
- Sponsor
- Medical University of Lodz
- Enrollment
- 100
- Locations
- 1
- Primary Endpoint
- Depression symptoms under examination-related stress
- Status
- Completed
- Last Updated
- last year
Overview
Brief Summary
Probiotics are "live microorganisms which when administered in adequate amounts confer a health benefit on the host". Accumulating evidence indicates their effect in mental health restoration. Beneficial neuropsychological and psychobiological effects are particularly well substantiated in clinical samples. However, it is not clearly documented whether probiotic supplementation reduces depressive and anxiety symptoms in healthy volunteers experiencing temporal deterioration in mental functioning while facing a stressful event. The combination of Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 is particularly well studied in terms of its central nervous system action with significantly deciphered mechanism. As a result, this combination is particularly promising to study the effect of mental health improvement in healthy volunteers facing a stressful event.
The aim of this project is to assess the impact of a 8-week supplementation with probiotic combination of Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 strains in the daily dose of 3 × 10^9 colony forming units on mental health measures and oral microbiota composition and metabolome in healthy young adults facing a psychologically stressful event. The aim will be achieved by comparing the probiotic combination supplement to placebo in a randomized triple-blind controlled trial settings with a participant allocation ratio of 1:1.
The summer academic examination session and the upcoming first take of the final exam in pharmacology at third year of medical studies will be a model of a stressful event. The participants will supplement their diets with probiotic/placebo for 8 weeks before the exam. After giving written informed consent, before the supplementation (relatively stress-free time period in terms of academic activities) the participants will provide background sociodemographic, anthropometric and psychometric data. At that time, participants will also give samples of saliva to assess cortisol and selected cytokines concentrations as well as salivary microbiome and metabolome. At the end of supplementation, a day before the final exam, participants will donate salivary samples and do psychometric tests for the second time to assess the same parameters as at the beginning of the study. Participants will also do a pre-exam test in pharmacology (not considered a formal academic assessment) as a comparator for the results of the formal examination held a day after.
Investigators
Michal Karbownik
Associate Professor
Medical University of Lodz
Eligibility Criteria
Inclusion Criteria
- •status of a third-year medical student at the Faculty of Medicine of the Medical University of Lodz
- •age (18-30 years)
- •high motivation and no formal obstacles to sit the first take of the final exam in pharmacology
- •Body mass index of 18-25 kg/m2
Exclusion Criteria
- •chronic dental diseases (in particular periodontal diseases), neurological, psychiatric, cardiological, gastroenterological, endocrinological, immunological, inflammatory or infectious diseases or disorders
- •psychiatric or neurological diagnosis - within the last 1 year
- •immune disorders or possible immunodeficiency - within the last 5 years
- •previous bariatric surgery - within the last 5 years
- •hospitalization - within the last 3 months
- •presence of central venous catheters
- •use of enteral nutrition (feeding tube or nutritional fistula)
- •pregnant or planning to become pregnant in the next 3 months
- •breast-feeding
- •occurrence of an allergic reaction - within the last 3 months
Outcomes
Primary Outcomes
Depression symptoms under examination-related stress
Time Frame: Day 0, Day 55
Depression symptoms measured with Depression Anxiety Stress Scale - 21 (DASS-21). Seven items, each scored 0 to 3 points, yielding a total between 0 and 21 points. The more points the more severe depression.
Cortisol
Time Frame: Day 0, Day 55
Salivary cortisol level measured with ELISA test
Anxiety symptoms under examination-related stress
Time Frame: Day 0, Day 55
Anxiety symptoms measured with Depression Anxiety Stress Scale - 21 (DASS-21). Seven items, each scored 0 to 3 points, yielding a total between 0 and 21 points. The more points the more severe anxiety.
Stress symptoms under examination-related stress
Time Frame: Day 0, Day 55
Stress symptoms measured with Depression Anxiety Stress Scale - 21 (DASS-21). Seven items, each scored 0 to 3 points, yielding a total between 0 and 21 points. The more points the more severe stress.
Performance under examination-related stress
Time Frame: Day 56
Number of correctly-answered questions in the final examination in pharmacology in relation to subject knowledge assessed in the pre-exam test. 60 questions, each scored 0 or 1 point, yielding a total between 0 and 60 points. The more points the better performance under examination-related stress.
Secondary Outcomes
- Depression symptoms under examination-related stress (supportive measure)(Day 0, Day 55)
- Anxiety symptoms under examination-related stress (supportive measure)(Day 0, Day 55)
- Interleukin-8 (IL-8)(Day 0, Day 55)
- Microbiome(Day 0, Day 55)
- Metabolome(Day 0, Day 55)
- Fatigue under examination-related stress(Day 0, Day 55)
- Interleukin-1β (IL-1β)(Day 0, Day 55)
- Mood(Day 0, Day 55)
- Sleep quality under examination-related stress(Day 0, Day 55)