Parabacteroides distasonis ameliorates insulin resistance via activation of intestinal GPR109a

The gut microbiota plays a pivotal role in insulin resistance (IR). In this study, we conducted a case-control study on Chinese adults and found a negative correlation between Parabacteroides distasonis and IR. Oral administration of P. distasonis in mice effectively improved IR. Furthermore, we also performed a screening of bioactive dietary fibers to induce the growth of P. distasonis and discovered that Dendrobium officinale polysaccharide (DOP) exhibited a favorable growth-promoting effect on P. distasonis and improved IR in mice. These findings uncover the unique mechanisms by which P. distasonis influences IR and provide feasible strategies for utilizing bioactive dietary fibers in the treatment and prevention of IR. The sequencing data included in the project were 16S rRNA amplicon sequencing, including: 1. analysis of the differences in gut microbiota between Chinese adult type 2 diabetes patients and healthy individuals (a total of 60 samples). 2. investigation of the effects of three dietary fibers, DOP, inulin (IN), and B-glucan (BG), on the gut microbiota of type 2 diabetes patients in vitro (a total of 120 samples). 3. evaluation of the impact of DOP on the gut microbiota of IR mice (a total of 12 samples).