Short chain fatty acids (SCFA), the products of gut bacteria metabolism and their role in the host

Gut bacterial consortium is essential for the homeostasis of the immune system in mammals. A significant role in maintaining this balance play short-chain fatty acids (SCFA), bacterial metabolites resulting from fermentation of dietary oligosaccharides. The most significant are butyric, propionic and acetic acids present in the microbiome in a specified mole ratio, but these proportions may change due to diet, age, diseases, and other factors. SCFA are the type of messengers between microbiota and immune system. They are responsible for maintaining the balance in the pro-and anti-inflammatory reaction through the set of free fatty acid receptors (GPR). Short chain fatty acids may induce regulatory T-cells (Treg) by an inhibition of histone deacetylase enzyme; the biggest inhibitory potential has butyric acid, causing proliferation and an increase of the functional capabilities of Treg cells. Manipulation of the gut microbiome composition and SCFA level constitutes a promising tool supporting treatment of chronic gastrointestinal diseases associated with an inflammation or caused by dysbiosis due to intensive use of antibiotics.