Role and mechanism of gut microbiota and metabolites in schizophrenia complicated with sleep disorder.

Schizophrenia (SCZ) is a major mental disorder with a high disability rate, and its pathogenesis involves the interaction of multiple factors such as genetics, environment, immunity, and neurodevelopment. Most SCZ patients are complicated with significant sleep disorder (SD), manifested as insomnia, sleep fragmentation, reduction in slow-wave sleep, and circadian rhythm disturbance. This comorbidity not only aggravates the severity of psychiatric symptoms but also significantly impacts treatment adherence and long-term prognosis. In recent years, the role of gut microbiota and its metabolites in mental diseases has received increasing attention. Existing studies have shown that the gut microbiota regulates brain function through the microbiota-gut-brain axis, affects the metabolism of neurotransmitters and immune-inflammatory responses, and thus may play an important role in the occurrence and development of SCZ and SD. However, the specific mechanism is still not clear enough at present, and there are still deficiencies in relevant studies. This article reviews the characteristics of gut microbiota diversity and metabolome related to sleep in SCZ patients, explores the potential mechanism of the role of gut microbiota and its metabolites in SCZ complicated with SD, provides a new microbial-metabolic perspective for understanding the pathogenesis of SD in SCZ patients, and suggests the potential therapeutic value of improving sleep problems in SCZ patients through probiotic intervention or metabolic regulation. These findings not only deepen the understanding of the comorbidity mechanism of mental diseases and SD but also provide a theoretical basis for new intervention strategies based on the gut-brain axis.