The Role of Gut Microbiota-Targeted Interventions in the Treatment of Depression
DOI:
https://doi.org/10.12775/JEHS.2026.88.67972Keywords
Depression, Gut–brain axis, Gut microbiota, Probiotics, Prebiotics, SynbioticsAbstract
Aim: This review summarizes current evidence on the role of gut microbiota modulation using probiotics, prebiotics, and synbiotics in the treatment of depression, with particular emphasis on clinical studies and mechanisms of the gut–brain axis.
Introduction: Depression is a prevalent mood disorder affecting more than 280 million people worldwide and is often resistant to standard pharmacological and psychotherapeutic treatments. Growing evidence from animal and human studies indicates that gut microbiota influences brain function and emotional regulation. Dysbiosis may contribute to neuroinflammation, altered neurotransmitter activity, and dysregulation of the hypothalamic–pituitary–adrenal (HPA) axis, thereby worsening depressive symptoms.
Methods: A review of meta-analyses and randomized controlled trials published between 2016 and 2024 was conducted. Studies included adults with depression or comorbid depression and anxiety who received probiotics, prebiotics, or synbiotics. Depression severity was assessed using validated clinical scales.
Results: Probiotic supplementation, particularly multi-strain formulations containing Lactobacillus and Bifidobacterium, was associated with significant reductions in depressive symptoms. Proposed mechanisms include modulation of gut microbiota composition, decreased pro-inflammatory cytokines (IL-1, IL-6), regulation of the HPA axis, effects on neurotransmitter metabolism (serotonin, dopamine, GABA), production of short-chain fatty acids, and vagus nerve activation. Synbiotics may enhance these effects, whereas prebiotics alone showed inconsistent outcomes.
Conclusion: Probiotics and synbiotics appear to be safe and promising adjuncts to standard depression treatment. Targeting the gut–brain axis may represent a future direction for personalized psychiatric interventions.
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Copyright (c) 2026 Justyna Jusiak, Michalina Janiszewska, Maria Łazik, Janusz Łuczak, Paulina Sobkowiak, Maciej Sobkowiak, Justyna Dżumaga, Jeremi Łuczak, Roksana Dybowska, Marta Walaszek
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