The characteristics of gut microbiota in type 2 diabetes mellitus patients with hypertriglyceridemia

Abstract

Objective: To investigate the characteristics of gut microbiota in type 2 diabetes mellitus (T2DM) patients with hypertriglyceridemia (HTG). Methods: Eighty-one patients first diagnosed with T2DM were enrolled in the Third Xiangya Hospital of Central South University from January 2018 to December 2020, including 58 patients [46 males and 12 females, aged (43±13) years] with HTG [HTG group, triglyceride (TG)≥1.7 mmol/L]. There were 23 cases without HTG (NTG group), including 20 males and 3 females, aged (46±13) years. According to the severity of HTG, the patients of HTG group were divided into severe HTG group (STG group, TG ≥5.6 mmol/L) and mild HTG group (MTG group, 1.7 mmol/L≤TG<5.6 mmol/L). Thirty healthy controls were matched accordingly, including 21 males and 9 females, aged (45±6) years. Clinical laboratory indicators and feces of the subjects were collected and 16S rRNA sequencing was performed to compare the differences in intestinal flora among the groups. Results: The Shannon and Simpson indexes in HTG group were lower than those in NTG group and healthy control group (5.02±0.91 vs 5.45±0.55 and 5.60±0.63, P=0.003; 0.90±0.06 vs 0.93±0.04, 0.94±0.04, P=0.002). Compared with healthy control group and NTG group, the abundance of intestinal P_Proteobacteria, g_Escherichia_Shigella, s_Escherichia_Coli and g_Clostridium_sensu_stricto_1 increased in HTG group, while the abundance of p_Firmicutes, g_Faecalibacterium and Faecalibacterium_prausnitzii decreased. The abundance of g_Clostridium_sensu_stricto_1 in the STG group was higher than that of NTG and MTG groups, while the abundance of g_Faecalibacterium decreased. Spearman correlation analysis suggested that g_Clostridium_sensu_stricto_1 was positively correlated with glycosylated hemoglobin (r=0.22, P=0.044), fasting blood glucose (r=0.36, P=0.001), TG (r=0.27, P=0.015) and total cholesterol (r=0.44, P<0.001). Logistic regression analysis indicated that g_Faecalibacterium was a protective factor for T2DM with HTG(OR=0.90, 95%CI:0.83-0.97, P=0.006). Conclusions: The intestinal flora of T2DM patients with HTG was dysregulated, which was manifested as decreased diversity, increased abundance of P_Proteobacteria and decreased abundance of p_Firmicutes. g_Faecalibacterium is a protective factor for T2DM with HTG.