مقالات پذیرفته شده در نهمین کنگره بین المللی زیست پزشکی
The Effect of Probiotics on the Gut Microbiome and Depression
The Effect of Probiotics on the Gut Microbiome and Depression
Setayesh Nouri,1Atena Tahmasebi,2Yasna Azizpour,3,*
1. Department of Biology, SR.C., Islamic Azad University, Tehran, Iran. 2. Department of Biology, SR.C., Islamic Azad University, Tehran, Iran. 3. Department of Biology, SR.C., Islamic Azad University, Tehran, Iran.
Introduction: Depression is among the most frequent mental disorders, ranking second according to the World Health Organization's statistics. At the beginning of the twentieth century, a new scientific hypothesis emerged: physicians noticed the concomitant onset of the symptoms of depression with bowel illnesses and concluded that bowel health may influence mental disorders like depression. However, that relation remained just a hypothesis until the early 2010s. During the last two decades, many studies have investigated the gut-brain axis and its reciprocal communications. Such relation was confirmed through neural, endocrine, and immune routes.
The first experiments were conducted on germ-free mice, which demonstrated that the absence of gut microbiota led to depression-related outcomes, such as disordered stress responses and altered neurotransmitter levels.
By the early 2010s, the evidence confirmed that probiotics are capable of decreasing the signs of depression; they are called psychobiotics and are helpful bacteria in the therapy of mental disorders.
To synthesize preclinical and clinical evidence on how gut microbiota composition and microbiota-targeted therapies influence emotional regulation and depression.
Methods: This study reviews and synthesizes findings from 16 seminal papers (2010–2024) on probiotics, prebiotics, synbiotics, metabolite pathways, and microbiome composition.
Results: Evidence from animal models and human clinical trials indicates that the gut–brain axis plays a key role in the pathogenesis of depression.
A specific strain of probiotic bacteria is CCFM1025, classified within the species Bifidobacterium breve. This organism plays a role in the regulation of the gut-brain axis, and research has shown its potential antidepressant properties. Findings from studies indicated that this bacterium is safe and does not produce adverse effects. Notably, this probiotic has a distinct impact on tryptophan pathways, and in human trials, it has resulted in a considerable decrease in depression scores over a short duration.
Future Research Directions: Conducting studies with bigger sample sizes and longer duration; assessment of immune mediators and inflammatory markers; exploration of effect longevity following drug withdrawal; exploring special clinical subgroups (e.g., subjects with endogenous major depressive disorders or comorbid gastrointestinal disorders).
Conclusion: Psychobiotics are promising but require longer, large RCTs, mechanistic biomarker studies, and convergence with measures of diet and neuroimaging. Clinical utility is greatest in patients with gastrointestinal symptoms or serotonergic-related side effects, in whom probiotics may be employed as an add-on or alternative therapy.