O eixo microbiota-intestino-cérebro desvendando a relação entre disbiose e a fisiopatologia da esquizofrenia

Abstract

Schizophrenia is a severe psychiatric disorder with a multifactorial etiology, and recent evidence highlights the role of the gut-brain axis in its pathophysiology. This integrative review aimed to synthesize current evidence on the relationship between gut dysbiosis and schizophrenia. A total of 38 studies were analyzed, including metagenomic research, clinical trials, and experimental models involving fecal microbiota transplantation (FMT). The results demonstrate a recurring microbial signature in schizophrenia, characterized by reduced alpha diversity, enrichment of Veillonella, and depletion of short-chain fatty acid (SCFA)-producing bacteria such as Roseburia and Faecalibacterium. These alterations are correlated with dysregulation of metabolic and neurochemical pathways, including altered plasma SCFA levels and a shift in tryptophan metabolism toward the kynurenine pathway. FMT studies provide causal evidence, demonstrating that dysbiosis can transfer behavioral and neurochemical phenotypes related to the disorder. It was also identified that these microbial changes promote neuroinflammation and compromise the blood-brain barrier. Therefore, the modulation of the gut microbiota represents a promising therapeutic strategy, although further studies are needed to validate interventions such as psychobiotics and microbial biomarkers in robust clinical trials.