Short-chain fatty acids: metabolism, functions and diagnostic capacity in metabolic disorders

The purpose of this review is to analyze the role of short-chain fatty acids (SCFAs), such as acetate, propionate, and butyrate, in maintaining gastrointestinal health, metabolism, and the development of metabolic diseases, including obesity, type 2 diabetes, and non-alcoholic fatty liver disease (NAFLD). SCFAs are produced as a result of dietary fibers fermentation by gut microbiota and play a key role in the regulation of numerous processes. Acetate, propionate, and butyrate influence glucose and lipid metabolism, insulin sensitivity, and inflammatory responses. In NAFLD and other metabolic disorders, changes in fecal and circulating SCFA levels are observed, and this fact suggests their potential as diagnostic biomarkers. Conflicting data concerning SCFA concentrations in different stages of diseases make further research necessary to understand their role in pathogenesis. The gut-liver axis and the connection with microbial metabolites, such as SCFAs, play a significant role in the development and progression of NAFLD. SCFAs may serve as promising diagnostic markers for assessing metabolic disorders, including NAFLD, obesity, and diabetes. Their concentrations in various biological samples provide important insights into the state of gut microbiota and can aid in early diagnosis and monitoring of metabolic disease progression and cardiovascular complications.