Effects Of Lactobacillus On Glucolipids Metabolism And Intestinal Flora In Type 2 Diabetic Mice Fed With High-glucose And High-fat Diet

Objective:To study and analyze effects of lactobacillu that in vitro lipid-lowering on glucolipid metabolism and gut microbiome composition.Method:Two strains of lipid-lowering lactobacillus were screened from laboratory 6 strains lactobacillus by cholesterol lowering,acid and bile salt resistance in vitro test.The diabetes mice model was established by high-glucose and high-fat diet combined with streptozotocin?STZ?.100male Balb/c mice were randomly divided into four groups?25 per group?,the control group?N?was fed as normal,the model group?M?was fed with high-sugar and high-fat diet,SY13 group?SY13?was fed with high-sugar and high-fat diet with SY13 bacteria,36group?36?was fed with high-sugar and high-fat diet with 36 bacteria.The model was feed for 14 weeks used to evaluate preventive and therapeutic effects.Mice were killed respectively at the end of 6^th week and 14^th week,to detected their blood glucose,blood lipid and other related biochemical indexes,HE staining was used to observe the pathological changes of pancreatic tissue,and mRNA expression of IL-10 and Adipoq genes in epididymal adipose tissue were detected by qRT-PCR at the end of 14^th week.In addition,explore the impact of lactobacillus on intestinal microflora abundance and diversity at the end of 6^th week and 14^th week.Result:1.L.casei SY13 and 36 were selected that equipped with high lipid-lowering ability by cholesterol lowering,acid and bile salt resistance in vitro test.2.At end of 6^th week,M group fasting blood glucose value was 10.63mmol/L,N group was 6.43mmol/L,M group blood sugar had a significantly higher than N group?P<0.05?.M group the content of serum total cholesterol?TC??5.26mmol/L?is significantly higher than N group?3.97 mmol/L?,?P<0.05?,the difference value is 1.29 mmol/L.M group content of triglyceride?TG??1.36mmol/L?higher than the N group?1.29mmol/L?,the difference value is 0.07mmol/L.The above three indexs indicated that high-fat diabetes mice model building success.3.End of feeding(the end of 14^th week),compared with M group,SY13 group and 36 group were improved mice glucose metabolism disorder.And significantly decreased levels of serum TC and LDL-C?P<0.05?,increased the level of serum HDL-C and the content of anti-inflammatory factor IL-10.The activities of GSH-Px,SOD and CAT in liver were increased in different degrees,while the activity of MDA was dramatically decreased?P<0.05?.Obviously,alleviated the pathological degree of islet and adenocytic cells.And promoted the expression of IL-10 and Adipoq mRNA in adipose tissue.4.Intestinal flora results at the end of 6^th week and 14^th week showed that high-fat mice intestinal flora diversity is lower than normal mice,also changed a lot in the species composition.Compared with M group,in the level of phylum,SY13 group and 36 group can reduce the Bactercidetes/Firmicutes abundance ratio,which was positively correlated with blood sugar levels,shows that liquid bacteria feeding may decrease the blood sugar level.And in the level of family,both strains of lactobacillus could reduce the abundance of Bacteroidates-S24-7–group,so that the Lactobacillaceae could maintain a high level and increase the number of beneficial bacteria in the intestinal tract.In the level of genus,the relative abundance of Bacteroides in lactobacillu feeding group intestinal tract was increased,which could prevent insulin resistance in mice induced by high-fat diet and alleviate the symptoms of diabetes.SY13 group and 36 group Lactobacillus genus relative content decreased from the end of 6^th week to 14^th week.This could be the bacteria colonize ability decreased as the extension of time.But,its abundance still significantly higher than that of M group?P<0.05?.The feeding of SY13 lactobacillus can decrease the abundance of Desulfovibrio in the intestinal tract of diabetic mice and close to N group,reducing the risk of diabetic complications by alleviating the inflammatory reaction.Finally,NMDS analysis found,that the more duration of liquid bacteria feeding,the less intestinal flora composition differences between high-fat diabetes mice and normal mice.Of course,intestinal flora structure adjustment and improved obviously.