The beneficial role of probiotic akkermansia muciniphila in inflammatory bowel disease

Abstract Inflammatory bowel diseases (IBD), including Crohn’s disease and ulcerative colitis, is a chronic relapsing gastrointestinal inflammatory disease mediated by dysregulated immune responses to resident intestinal microbiota. Current conventional approaches including aminosalicylates, corticosteroids, immunosuppressive agents, and biological therapies are focused on reducing intestinal inflammation besides inducing and maintaining disease remission, and managing complications. However, these therapies are not curative and are associated with various limitations, such as drug resistance, low responsiveness and adverse events. Recent accumulated evidence has revealed the involvement of mucin-degrading bacterium Akkermansia muciniphila (A. muciniphila) in the regulation of host barrier function and immune response. Although the role of commensal A. muciniphila in IBD is controversial and needs further investigations, most clinical and experimental results still support the protective effect of A. muciniphila in the process and development of intestinal inflammation. Therefore, A. muciniphila-targeted and -based therapies is now considered a valuable therapeutic approach to treat IBD patients. However, how to selectively enrich the growth and colonization of A. muciniphila in the host intestine with direct or indirect interventions have not been clarified. This review reveals an interesting phenomenon that not only viable A. muciniphila, but pasteurised A. muciniphila, and its ingredients such as AmEVs, Amuc_1100 and P9 also can alleviate intestinal inflammation, suggesting a therapeutic potential of A. muciniphila in the treatment of IBD. More importantly, because of the natural characteristics individual strains grow, we believe that it is more promising weapon for the treatment of IBD to improve the intestinal microenvironment of A. muciniphila than to simply increase the number of individual bacteria itself. Therefore, it has become a research hotspot in recent years to improve intestinal microenvironment and indirectly promote the colonization of A. muciniphila through the supplementation of other probiotic or prebiotics, natural diets, drugs, and herbs, and achieved good progress, holds promise for A. muciniphila-targeted and -based therapies in the treatment of IBD.