肠道菌Akkermansia muciniphila的特性及其与机体健康的关系

Characteristics of intestinal bacterium Akkermansia muciniphila and the association with host health

Akkermansia muciniphila是一种从粪便中分离到的严格厌氧肠道菌,在肠道中的丰度通常占1%-3%,可以利用肠道黏蛋白作为唯一碳源和氮源进行生长,主要代谢产物为丙酸。Akkermansia muciniphila在肠道中的定殖与宿主的健康息息相关,它可以改善肥胖、糖尿病患者的炎症反应以及胰岛素抵抗和葡萄糖耐受等不良症状,还可以调节机体的免疫应答,维持体内代谢平衡。虽然多数情况下该菌表现出有益作用,也有个别研究发现高血红素铁膳食诱导的肠道上皮细胞增生与Akkermansia muciniphila丰度的增加有关,可破坏肠道黏液层。然而,关于该菌利用黏蛋白的代谢机制及其影响宿主健康的机制尚不清楚,有待进一步探索。

Akkermansia muciniphila was isolated from human faeces in anaerobic medium containing gastric mucin as the sole carbon and nitrogen source. It represents approximately 1% to 3% of the total microbiota in the intestine of healthy adult, and it produces propionic acid as main metabolite. This mucin-degrading bacterium has been closely correlated with host health. A. muciniphila administration could enhance glucose tolerance, reduce insulin resistance, modulate pathways involved in establishing homeostasis for basal metabolism and immune tolerance toward commensal microbiota. But on the contrary, the abundance of the mucin-degrading A. muciniphila was significantly increased by heine diet, which is associated with epithelial hyperproliferation, and destroyed mucus layer. The mechanisms of mucin utilization by this bacterium in the gut and the interactive mechanisms between A. muciniphila and host is still unknown and need further explorations.