Electroacupuncture at Lower He-Sea and Front-Mu Acupoints Ameliorates Insulin Resistance in Type 2 Diabetes Mellitus by Regulating the Intestinal Flora and Gut Barrier

INTRODUCTION: The study objective was to investigate the effects of electroacupuncture performed at the he-sea and front-mu acupoints on the intestinal microflora and intestinal barrier in db/db mice and to explore the related mechanism in type 2 diabetes mellitus. METHODS: Db/m mice in the normal control group (NOC), electroacupuncture group (EA), metformin group (MET) and T2DM group (T2DM) were used as model controls, and db/db mice were used in all three groups, with 8 mice in each group. The treatment period was 2 weeks. Fasting blood glucose (FBG) and triglyceride (TG) levels were measured. Lipopolysaccharide (LPS) and tumor necrosis factor-α (TNF-α) levels were detected by enzyme-linked immune sorbent assay (ELISA). The ileal tissue was stained with hematoxylin-eosin staining (H&E), and histopathological changes were observed under a light microscope. Illumina sequencing was used to analyze the V4 region of the 16S rRNA gene to evaluate the effect of EA on the intestinal flora. RESULTS: Our results suggest that EA treatment can reduce the expression of diabetes-related markers, with an effect similar to that of metformin. After EA intervention, the abundance of Firmicutes and the ratio of Firmicutes to Bacteroidetes increased, while the abundances of Bacteroidetes and Eubacterium decreased. In addition, the serum levels of LPS and TNF-α in the electroacupuncture group were downregulated, and ileal tissue damage was alleviated under an electron microscope. CONCLUSION: EA combined with acupoints can restore the intestinal flora structure, decrease the blood LPS level, reduce levels of inflammation, maintain the integrity of the intestinal barrier, and play a therapeutic role in the treatment of T2DM, mainly by increasing the abundance of Firmicutes and the ratio of Firmicutes to Bacteroidetes and decreasing the abundances of Bacteroidetes and Eubacterium.