Abstract
Objective: To analyze the available scientific evidence regarding the role of the gut microbiome in psychiatric disorders, focusing on the biological mechanisms involved in the gut-brain axis, with the aim of clarifying whether alterations in gut microbiota composition play a causal role in the pathophysiology of these disorders or primarily represent a consequence associated with these conditions. Literature review: The gut microbiota plays an important role in communication between the intestine and the central nervous system through the gut-brain axis, participating in the regulation of immune responses, metabolism, and the production of neurotransmitters and neuroactive molecules. Alterations in microbial composition and diversity, characterized by dysbiosis, may contribute to neuroinflammatory processes, changes in intestinal permeability, dysregulation of the hypothalamic-pituitary-adrenal axis, and alterations in serotonergic, dopaminergic, and GABAergic signaling, and have been associated with the pathophysiology of disorders such as depression and anxiety. Final considerations: Understanding the interaction between the gut microbiota and the central nervous system highlights the potential of the gut-brain axis as a therapeutic target, supporting the development of adjunctive strategies for the prevention and treatment of psychiatric disorders.
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