Akkermansia muciniphila as a novel powerful bacterial player in the treatment of metabolic disorders.

Akkermansia muciniphila (A. muciniphila) is a mucin-degrading bacterium that commonly lives in the intestinal mucus layer. It is normally detected in human faecal specimens and is one of the few bacteria potentially associated to obesity development. In this narrative review, possible mechanisms that support how A. muciniphila is implicated in the pathogenesis of obesity and metabolic-associated disease are described with the evaluation of its role as an intermediary or independent agent whose manipulation could be useful in the management of metabolic disorders. The ampleness of A. muciniphila is notably diminished in obesity, type 2 diabetes (T2D), non-alcoholic fatty liver disease (NAFLD), cardiometabolic diseases and low-grade inflammation. Furthermore, an inverse relationship between A. muciniphila, body weight and insulin sensitivity has been observed in both humans and animals. Antidiabetic drugs, gastric bypass surgery, prebiotics and biologically active compounds, such as polyphenols or saponins, have been shown to be associated with A. muciniphila relative abundance and thus could have favourable effects on metabolic disorders. Furthermore, A. muciniphila supplementation alone has been correlated with weight reduction and improvement of metabolic disorders, including fat mass gain, adipose tissue inflammation, metabolic endotoxaemia, and insulin resistance. Nevertheless, since the primary beneficial impacts of this bacterium have been predominantly investigated in various preclinical models, these results need to be confirmed in randomized clinical trials.