MicroRNAs: Decoders of Dysbiosis into Metabolic Diseases?

The identification of molecular factors bridging gut microbiota dysbiosis to alterations of host metabolism still remains a major goal in biomedical research. In fact, on one hand, there is a worldwide consensus about the systemic impact, from brain to liver, from heart to adipose tissue, of gut microbiota dysbiosis. On the other hand, beyond the microbial production of short chain fatty acids and their vast metabolic properties, little is known about the molecular mechanisms linking a change in the activity of gut microbes to a modification of host cell metabolism. In this context, microRNAs (also known as miRs) are promising molecules which could allow explaining how dysbiosis is converted into metabolic outcomes since: 1miRs are pleiotropic regulators of gene expression, targeting multiple mRNAs at once; 2miRs expression in specific organs such as the intestine has been demonstrated to be under the control of gut microbiota; 3alterations in miRs expression have been found in the majority of tissues targeted by gut microbiota dysbiosis during metabolic diseases such as liver, adipose tissue, pancreas, skeletal muscle, intestine, heart and also the brain. In this review publications in the growing field of miRsbased metabolic control at a systemic level will be discussed together with a putative link with gut microbiota dysbiosis.