Gut microbiota is an endocrine organ

The gut microbiota affects the processes of food digestion, intestinal peristalsis, controls the work of the intestinal epithelium, has protective properties against pathogenic microorganisms, activating local immunity and stimulating the secretion of mucus by intestinal cells. Besides the gut microbiota participates in the metabolism of proteins, fats and carbohydrates, mediates the processes of gluconeogenesis, glycogenolysis, lipogenesis and lipolysis, and affects on feelings of hunger and satiety. All these processes occur because the gut microbiota produces active metabolites throughout their life activity. Gut microbiota and active metabolites of the gut microbiota activate the synthesis of hormones. The gut microbiota affects the synthesis of hormones such as glucagon-like peptide-1, glucagon-like peptide-2, YY-peptide, glucose-dependent insu-linotropic peptide, ghrelin, leptin, cholecystokinin, serotonin, and insulin. Disturbance of the secretion of these hormones is one of the links in the pathogenesis of endocrine diseases such as diabetes and obesity. Thus, the gut microbiota is an endocrine organ. Changes in the composition and functions of the gut microbiota lead to metabolic disorders.

This article describes the effect of gut germs and active metabolites of the gut microbiota on the synthesis hormones by means of receptor mechanisms, genes, and enzymes.

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