Obsessive-Compulsive Disorder and the Gut Microbiota: The Microbiota–Gut–Brain Axis and Therapeutic Approaches
Keywords:
Obsessive-compulsive disorder, Gut microbiota, Microbiota-gut-brain axis, Probiotics, Dietary patternsAbstract
Obsessive-compulsive disorder (OCD) is a psychiatric disorder characterized by obsessions and compulsions that significantly impair functioning, affecting approximately 1–3% of individuals during their lifetime. The persistence of clinically significant symptoms in a sizable percentage of patients necessitates the development of novel treatment strategies despite existing pharmacological and psychotherapy methods. According to recent research, the pathophysiology of OCD may be significantly influenced by the gut-brain-microbiome axis, which characterizes the bidirectional communication between the gut microbiota and the central nervous system. This review examines the relationship between OCD and gut microbiota through the lens of short-chain fatty acids (SCFAs), neurotransmitter modulation, inflammatory pathways, and microbiota-derived metabolites. Through the hypothalamus-pituitary-adrenal (HPA) axis and the vagus nerve, neuroimmune and neurohumoral pathways mediate the reciprocal relationship between gut microbiota and OCD. According to research, OCD may be associated with dysbiosis, reduced microbial diversity, poor formation of SCFAs, and abnormalities in neurotransmitter systems like serotonin, dopamine, glutamate, and GABA. It is also reported that a Western-style diet, which is low in fiber, may contribute to this process by negatively affecting microbiota composition. It has been suggested that microbiota-based interventions, such as probiotics, prebiotics, synbiotics, and micronutrient supplements, may have potential regulatory effects on OCD symptoms. In conclusion, approaches targeting the gut microbiota appear promising for developing new complementary and supportive strategies in the treatment of OCD.
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