A narrative review of relationship between gut microbiota and neuropsychiatric disorders: mechanisms and clinical application of probiotics and prebiotics.

The gut microbiota is a kind of fixed-value bacteria in the human intestine, characterized by a large quantity, a wide variety and interdependence with each other and with the host. The gut microbiota is considered to be an important link in maintaining health and pathogenic mechanism of many diseases. The gut microbiota affects the central nervous system under the action of the microbe-gut-brain axis through nerve, immune, endocrine and metabolic pathways. The gut microbiota not only regulates the gastrointestinal tract but plays a vital role in the development and function of the brain. More and more studies believe that normal gut microbiota is essential for the development of the central nervous system and emotional regulation. The imbalance of the gut microbiota can affect some neuropsychiatric diseases. Probiotics and prebiotics are active microorganisms beneficial to the human body and can regulate the microecological balance of the human intestinal tract. Current research shows that probiotics and prebiotics have a good preventive effect on Alzheimer's disease, Parkinson's disease, depression, autism spectrum disorders and other neurological and mental diseases. Based on this, we review the relevant research on the pathogenesis of probiotics and prebiotics and neuropsychiatric diseases, in an attempt to providing new ideas for exploring the treatment and prevention of neuropsychiatric diseases.