Effect of Wumeiwan on Intestinal Microflora, Inflammatory Factor and Short Chain Fatty Acids in Type 2 Diabetic Rats / 中国实验方剂学杂志

ABSTRACT

Objective:To study the effects of Wumeiwan on blood glucose, intestinal microflora, tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10) and dietary fiber fermented by intestinal microflora in type 2 diabetic (T2DM) rats. Method:Totally 80 SD clean rats were selected as experimental subjects, and 10 of them were randomly selected as the normal group. The remaining 70 rats were given high-sugar and high-fat emulsion for 8 weeks and intraperitoneally injected with streptozotocin (STZ, 35 mg·kg-1) to establish the rat model of T2DM. The fasting blood glucose higher than 11.10 mmol·L-1 was considered as a successful model. The rats that were not successfully modeled were removed, and the remaining rats that were successfully modeled were randomly divided into model group, metformin group, high-dose Wumeiwan group, medium-dose Wumeiwan group and low-dose Wumeiwan group, with 10 rats in each group. Normal group and model group received (ig) normal saline (20 mL·kg-1·d-1), while metformin group (ig metformin 200 mg·kg-1·d-1), Wumeiwan high, medium and low dose groups (ig Wumeiwan 20, 10, and 5 g·kg-1·d-1) received corresponding drugs respectively. Blood glucose and body weight of rats were monitored regularly before and after administration of the drugs. Blood and feces were collected after four weeks of administration.16S-rDNA high-throughput sequencing technology was used for gene sequencing of intestinal flora. Enzyme linked immunoassay (ELISA) was used to detect the serum levels of inflammatory factors TNF-α and IL-10 in rats, and the contents of acetic acid, propionic acid and butyric acid in feces were detected by gas chromatography. Result:As compared with the normal group, the body weight decreased significantly (P<0.01). Bacteroidetes, Actinobacteria, Bacteroides, Clostridium increased, Firmicutes, Deltaproteobacteria, and Lactobacillus decreased, fasting blood glucose and serum TNF-α levels increased significantly (P<0.01), IL-10 level decreased (P<0.01), and the contents of acetic acid, propionic acid and n-butyric acid of short-chain fatty acids decreased(P<0.05, P<0.01) in model group. As compared with the model group, the body weight decreased; Bacteroidetes, Actinobacteria, Bacteroides and Clostridium decreased. Firmicutes, DeltaProteobacteria and Lactobacillus increased; fasting blood glucose and serum TNF-α decreased (P<0.01), and IL-10 increased (P<0.01), contents of acetic acid, propionic acid and n-butyric acid increased in Wumeiwan high-dose, medium-dose and low-dose groups and metformin group (P<0.05, P<0.01). Conclusion:Wumeiwan may prevent and treat T2DM by regulating intestinal flora, improving inflammatory response, increasing SCFAs content and reducing blood glucose.