White hyacinth bean polysaccharide ameliorates diabetes via microbiota-gut-brain axis in type 2 diabetes mellitus rats

Gut played a potent role in onset and progression of metabolic disorders, presenting an exciting direction for diabetes prevention. Here, the anti-diabetic effects of White hyacinth bean polysaccharides (WHBP) were observed, including the reduction of blood glucose levels and improvement of intestinal impairment in type 2 diabetes mellitus (T2DM) rats. Further data concerning intestinal protection suggested that WHBP restored intestinal barrier, as evidenced by inhibition of intestinal pathological damage, up-regulation of Zonula occluden-1 expression and manipulation of the redox system in T2DM rats. Moreover, WHBP-mediated anti-diabetic effects were in parallel with the adjustment of changes in gut microbiota composition of T2DM rats. Meanwhile, hypersecretion of corticotropin-releasing hormone, adrenocorticotropic hormone, and corticosterone levels, which were critical coordinators of the hypothalamic-pituitary-adrenal (HPA) axis, were suppressed in T2DM rats exposed to WHBP, indicating that WHBP-mediated health benefits were referring to regulate brain feedback in reduction of HPA axis. Concomitantly, further suggested and expanded on gut-brain communication by data of microbial metabolites short-chain fatty acids, mediators of gut-brain interactions, were remarkably raised in cecum contents of T2DM rats subjected to WHBP. Collectively, WHBP performed anti-diabetic effects were associated with control of microbiota-gut-brain axis implicated in intestinal barrier, HPA axis, gut microbiota and their metabolites.