Intestinal helminths reverse gut dysbiosis induced by urbanization: case study in a small rodent

本研究分析了184只啮齿类动物消化道沿着4个区域（小肠、盲肠、结肠和直肠）的肠道微生物群。argenteus和Myodes rufocanus）采集自城市公园和国家森林。我发现两种生境的微生物群落不同，城市M。rufocanus可能正在经历生态失调（即不健康的肠道微生物群）。尤其是Urban M. rufocanus在下胃肠道中具有较高丰度的潜在致病性螺杆菌。通过使用稳定同位素分析他们的饮食习惯，我发现城市A。speciosus表现出扩大的饮食生态位相比，他们的自然同种。此外，这两个物种都经历了饮食的转变，在城市栖息地根据他们的生活史与A。speciosus消耗较多的动物蛋白质; rufocanus更多C3植物。这种饮食变化部分解释了观察到的肠道微生物群变化。最后，我发现蠕虫可能有助于保护城市动物免受生态失调，通过促进益生菌物种，如Butyricicoccus。

I analyzed the gut microbiota in four regions (i.e. small intestine, cecum, colon, and rectum) along the digestive tract of 184 rodents comprised of three species (i.e. Apodemus speciosus, A. argenteus, and Myodes rufocanus) collected from urban parks and the national forest. I found that the microbial community differed between the two types of habitat and that urban M. rufocanus may be experiencing dysbiosis (i.e. unhealthy gut microbiota). In particular, urban M. rufocanus is harboring higher abundances of potentially pathogenic Helicobacter in the lower gastro intestinal tract. By analyzing their dietary habits using stable isotope analysis, I found that urban A. speciosus exhibited an expanded dietary niche as compared to their natural conspecifics. Furthermore, both species have undergone a dietary shift within the urban habitat in accordance with their life history with A. speciosus consuming more animal protein and M. rufocanus more C3 plants. This dietary shift partially explains the observed changes in the gut microbiota. Lastly, I found that helminths may help protect urban animals from dysbiosis through the promotion of probiotic bacterial species such as Butyricicoccus.