Effect of Probiotic on Depression

Study Overview
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Brief Summary
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Depressive disorder, also known as depression, is a type of mood disorder characterized by persistent low mood. The incidence of depression worldwide is about 6%. Growing evidence suggested that the gut microbiota plays a key role in the development of depression. Probiotics can effectively regulate gut microbiota, and showed potential in alleviating depression. This study investigated the effect of formula probiotic (containing Lactobacillus paracasei, Bifidobacterium animalis, Bifidobacterium longum, Bifidobacterium bifidum and Lactobacillus plantarum) on depression.

Official Title
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Effect of Probiotic on Depressive Symptom in Chinese Patients

Conditions
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Depression

Intervention / Treatment
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* Dietary Supplement: Probiotic
* Dietary Supplement: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Normal body mass index ≥ 18.5 until ≤ 29.9 Mild to moderate major depression diagnosed by psychiatrists according to the diagnostic criteria for depressive episodes in DSM-5 (American Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition)) Hamilton Rating Scale for Depression (HAMD-17) score not less than 8 Agreed to intake study product during the study period Agreed to sign written informed consent Exclusion Criteria: Use of systemic antibiotics or antimycotics medication in the 30 days prior to the study Investigator's uncertainty about the willingness or ability of subject to comply with the protocol requirements Persons with a milk protein allergy, lactose intolerance Pregnant or breastfeeding women Subject had other serious diseases

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Probiotic<br>Formula probiotic contains freeze-dried Lactobacillus casei, Bafidobacterium animals, Bifidobacterium longum, Bifidobacterium bidium and Lactobacillus plantarum, each at a dosage of 3.0E+10 CFU per 2g sachet. | Dietary Supplement: Probiotic<br>* Patients received the formula probiotic for consecutive 8 weeks ( one sachet per day ).<br>|
| Placebo Comparator: Placebo<br>Placebo made with only the excipients. The placebo sachet was matched to the study probiotic products for taste, color, and size. | Dietary Supplement: Placebo<br>* Patients received the placebo identical to probiotic for consecutive 8 weeks ( one sachet per day ).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hamilton Depression Rating Scale | Depressive symptoms as measured with the Hamilton Rating Scale for Depression. The score rangs from 0 to 53. The higher score means severer depressive symptoms. | Changes in the HAMD score at baseline and 8-week intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fecal microbiome | changes in the profile of gut microbiota before and after 8-week intervention. | Changes between at baseline and 8-week intervention | 
| Serum Il-1β | Serum Il-1β levels before and after intervention assessed by ELISA. | change from baseline to intervention measurements at 8 weeks | 
| Serum Il-6 | Serum Il-6 levels before and after intervention assessed by ELISA. | change from baseline to intervention measurements at 8 weeks | 
| Serum TNF-α | Serum TNF-α levels before and after intervention assessed by ELISA. | change from baseline to intervention measurements at 8 weeks | 
| Serum cortisol | Serum cortisol levels before and after intervention assessed by ELISA. | change from baseline to intervention measurements at 8 weeks | 
| Serum Brain-derived neurotrophic factor | Serum Brain-derived neurotrophic factor levels before and after intervention assessed by ELISA. | change from baseline to intervention measurements at 8 weeks |