Characteristics of intestinal microbiota in patients with type 2 diabetes mellitus and obesity and its relationship with insulin resistance in Qinghai region
Objective To investigate the characteristics of intestinal microbiota and its relationship with insulin resistance(IR)in patients with type 2 diabetes mellitus(T2DM)and obesity.Methods A total of 80 patients with newly diagnosed T2DM were enrolled in this study from The Second Department of Endocrinology,Qinghai Provincial People's Hospital and divided into simple T2DM group(T2DM,n=40)and T2DM combined with obesity group(Obe,n=40)according to the combination of obesity.The differences of diet structure,biochemical indexes and intestinal flora were compared between the two groups,and the relationship between intestinal flora and BMI,IR was analyzed.Results Compared with the T2DM group,BMI,WC,TG,HOMA-IR,and intake of refined grains,poultry and eggs,and cooking oil were significantly higher(P<0.05),while in take of vegetables and fruits was significantly lower in the Obe group(P<0.05).Microbiota analysis showed that there were 647 OTUs in both groups,90 specific to the T2DM group and 114 specific to the Obe group.The difference of intestinal flora was greater between the two groups than that within the group(P<0.05),and the differences within and between the groups were the least at the phylum level(P<0.05).The dominant flora were Bacteroides and Firmicutes.There were significant differences in the relative abundance of flora in 2 phyla,3 classes,5 orders,8 families,17 genera,and 15 species between the two groups(P<0.05).Bacteroides,Clostridium laprosii and Butylum were positively correlated with BMI(P<0.05),Bifidobacterium,Dialisteria,Streptococcus,Rosesia,Escherichia and Leptotrichia were negatively correlated with BMI(P<0.05).Fusobacterium was positively correlated with HOMA-IR(P<0.05).Conclusions Compared with patients with T2DM alone,patients with T2DM and obesity have a decreased proportion of beneficial bacteria and an increased proportion of pathogenic bacteria in the intestinal flora,which may further aggravate IR and affect the progression of T2DM.