MAFLD under the lens: the role of gut microbiota

Abstract

Obesity, the metabolic syndrome, and metabolic dysfunction-associated fatty liver disease (MAFLD) can be portrayed as transmissible diseases. Indeed, they can be induced, in animal models, by cohabitation or by transplantation of fecal microbiota from other animals or humans with those diseases. As such, to get a 10,000-foot view, we need to see under the lens the microbes that populate our gut. Gut microbiota participates in the harvesting of energy from nutrients, it allows the digestion of otherwise indigestible nutrients such as fibers, and it also produces short chain fatty acids and some vitamins while emitting different compounds that can regulate whole-body metabolism and elicit proinflammatory responses. The metabolic syndrome and MAFLD share physiopathology and also patterns of gut dysbiota. Moreover, MAFLD also correlates with dysbiota patterns that are associated with direct steatogenic or fibrogenic effects. In the last decade, a tremendous effort has allowed a fair understanding of the dysbiota patterns associated with MAFLD. More recently, research is moving towards the delineation of microbiota-targeted therapies to manage metabolic dysfunction and MAFLD. This review provides in-depth insight into the state-of-the-art of gut dysbiosis in MAFLD, targeting clinical hepatologists.

Keywords

MAFLD / gut microbiota / obesity / diabetes mellitus

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