关键词: 乳酸菌, 高糖高脂饮食, 血脂, 抗炎因子, 抗氧化活性

Abstract: Objective: To study the effects of two Lactobacillus strains on blood glucose, blood lipids, serum inflammatory cytokines, liver antioxidant level, pancreatic pathology, and the expression of the genes encodig interleukin-10 (IL-10) and adiponectin (adipoq) in epididymal adipose tissue in diabetic mice. Methods: Out of six Lactobacillus strains, two Lactobacillu casei strains (SY13 and D36) were selected for their potent lipid-lowering effect in terms of cholesterollowering ability, and acid and bile salt tolerance in vitro. The diabetic mouse model was established by feeding mice a highglucose and high-fat diet and injecting them with streptozotocin (STZ). Totally 100 male Balb/c mice were randomly divided into four groups of 25 mice per group: control, model, SY13 and D36 groups. The control group was fed a normal diet, while all the other groups were given a high-glucose and high-fat diet. The SY13 and D36 groups were additionally administered by gavage with Lactobacillu casei SY13 and D36, respectively. Some of the mice were scarified at the end of the sixth, tenth and fourth week of administration for the detection of blood glucose, blood lipids and other related biochemical indexes. HE staining was used to observe the pathological change of pancreatic tissues, and the mRNA expression of IL-10 and Adipoq genes in epididymal adipose tissues were detected by reverse transcription quantative real-time polymerase chain reaction. Results: L. casei SY13 and D36 had high cholesterol-lowering capacity, and strong acid and bile salt tolerance. Compared with the model group, both strains significantly repressed the increase in blood sugar and serum total cholesterol, triglyceride and low-density lipoprotein cholesterol levels, and increased the levels of serum high-density lipoprotein chrolestserol and anti-inflammatory factor interleukin-10 (IL-10) (P < 0.05). In addition, they significantly increased the activity of glutatione peroxidase, superoxide dismutase and catalase in liver and decreased malondialdehyde (P < 0.05). The strains also improved glucose metabolism disorders, obviously alleviated the pathological changes of islet and adenocytic cells, and promoted the mRNA expression of IL-10 and Adipoq genes in adipose tissues. Conclusion: Lactobacillus casei SY13 and D36 can significantly improve glucose and lipid metabolism in mice with diabetes induced by a high-glucose and high-fat diet combined with STZ injection.

Key words: Lactobacillus, high-glucose and high-fat diet, serum lipids, anti-inflammatory factor, antioxidant activity