Study Finds Probiotics Alleviate Depression, Improve Sleep
Much work indicates that the human gut microbiome is involved in mental health via bidirectional interactions within the gut-brain axis, which involves the immune, neural, endocrine, and metabolic pathways between the gut and the brain. Thus, oral intake of probiotics may have therapeutic effects on psychiatric symptoms by promoting a healthy and balanced gut microbiome.
In recent years, more and more publications suggest that probiotics composed of specific strains of genera Lactobacilliand Bifidobacteriummay have the potential to prevent and treat various psychiatric conditions such as depression and anxiety. However, the researchers behind the current study believe that only a few RCTs have investigated the effects of probiotics containing Lactobacilliand BifidobacteriumOn the mental health of healthy individuals, and the studies that do exist have used small sample sizes and failed to perform gut microbiome analyzes to confirm restoration of gut microbiome homeostasis – one of the most reliable markers of probiotic effects.
NVP-1704 probiotic is a blend of Lactobacillus reuteriNK33 and Bifidobacterium adolescentisNK98. Several preclinical trials have shown that NVP-1704 can relieve anxiety and depression in mice by modulating gut immune responses and the composition of the gut microbiota.
The present study aimed to examine the efficacy and safety of administration of NVP-1704 for the management of stress-related symptoms, such as depression, anxiety and insomnia, in healthy adults. The research team conducted a randomized, double-blind, placebo-controlled parallel study at Bundang Hospital, Seoul National University, Korea, with a sample of 22 participants, and included an analysis of the gut microbiome to confirm the effects of our intervention.
Participants were randomly assigned to the intervention or to the placebo group. They were asked to take two capsules with water once a day, daily, for eight weeks. Each 500 mg capsule of NVP-1704 contained 2.5 × 109Colony-forming units of microorganisms (2.0 × 109UFC for Lactobacillus reuteriNK33 and 0.5 × 109UFC for Bifidobacterium adolescentisNK98).
All participants were asked to complete self-report questionnaires regarding symptoms of stress, depression and anxiety on the first, third and last visits.
Subjective quality of sleep and symptoms of insomnia were assessed using the Pittsburgh Sleep Quality Index (PSQI) and Insomnia Severity Index (ISI), respectively.
Blood samples were taken during the initial and follow-up assessments. To assess the inflammatory response and the activity of the hypothalamic-pituitary-adrenal (HPA) axis, we measured the serum levels of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), adrenocorticotropic hormone (ACTH) and cortisol. Simultaneously, the blood level of brain-derived neurotrophic factor (BDNF) was assessed as an index of neuroplasticity.
Participants were invited to submit fecal samples during the final visit for bacterial sequencing.
24-hour dietary reminders and food diaries reported on the second, third and last visits, daily intakes of calories, carbohydrates, protein, fat, water, dietary fiber, vitamins and mineral nutrients were calculated.
The data obtained suggests that NVP-1704 is a safe and well-tolerated probiotic with beneficial effects on depression and sleep in healthy adults. Our study also revealed a significant reduction in serum levels of pro-inflammatory cytokine IL-6 after treatment with NVP-1704. Consistent with these results, our microbiome analysis demonstrated that individuals treated with NVP-1704 had a gut microbiota composition with reduced ratios of EnterobacteriaceaeTo Bifidobacteriaand EnterobacteriaceaeTo Lactobacillaceae, Which could be associated with better mental health.
They conclude that the significant reduction in serum levels of pro-inflammatory cytokine IL-6 suggests the administration of Bifidobacteriumand LactobacilliThe strains can down-regulate the secretion of pro-inflammatory cytokines.
Their report states: “Although the exact mechanism remains to be elucidated, modulation of neuroinflammatory pathways due to beneficial alteration in the gut microbiome may be the key elements underlying the beneficial effects of NVP-1704. Neuroinflammation induced by various medical conditions plays an important role in the pathophysiology of depression, anxiety, and insomnia. Therefore, IL-6 suppression could be responsible for the psychotropic effects of NVP-1704 treatment.
Large-scale and highly controlled longitudinal human studies may be conducted in the future to confirm the beneficial effects of various probiotics on mental health and sleep.
Lee, HJ; Hong, JK; Kim, J.-K. ; Kim, D.-H .; Jang, southwest; Han, S.-W .; Yoon, I.-Y.
“Effects of Probiotic NVP-1704 on Mental Health and Sleep in Healthy Adults: An 8-Week Randomized, Double-Blind, Placebo-Controlled Trial”
https://doi.org/10.3390/nu13082660 (DOI registration)