The Effect Of Milk-borne Composit Probiotics On The Regulation Of Intestinal Microbiota In Db/db Diabetic Mice

Objective:To observe the intestinal colonization ability of milk-borne composit probiotics(including 10 lactic acid bacteria and 4 yeasts)and their effects on glucose and lipid metabolism and gut microbiota in db/db diabetic mice,and analyzing whether their hypoglycemic mechanism is related to the regulation of intestinal microbiota.Methods:10 lactic acid bacteria and 4 yeast strains were tested for growth curve,bile salt tolerance and artificial gastrointestinal fluid tolerance.Based on the number of probiotics,composit probiotics were prepared in laboratory.32db/db diabetic mice were divided into four groups and treated for 6 weeks with Metformin(0.3g·kg-1),high dose composit probiotics(1×108 lactic acid bacteria+1×106 yeast)CFU,low dose(1×1010 lactic acid bacteria+1×108 yeast)CFU and a diabetic control group.In addition,10 57BL/Ks mice as normal control group were used for comparison.To observe the effects of composit probiotics on db/db diabetic mice body weight(BW),fasting blood glucose(FBG),glucose tolerance(OGTT),glycosylated hemoglobin(HbAlc),C-peptide,insulin resistance index(IRI),TC,TG,LDL-C,HDL-C,liver,kidney and pancreas histopathology,24mALB and intestinal microbiota.Results:l.Ten strains of lactic acid bacteria and four strains of yeast all have good growth curves,acid production,resistance to bile salts,and resistance to artificial gastrointestinal fluids.2.After 6 weeks of drug intervention,composit probiotics significantly reduced FBG(P<0.01),OGTT(P<0.05),HbAlc(P<0.05),insulin resistance index(P<0.05)and increased C-peptide(P<0.05)levels in db/db diabetic mice.Histological analysis of pancreatic tissue showed that composit probiotics increased the number of islets,islet volume,and the number of islet in db/db diabetic mice.3.The composit probiotics could significantly reduce the content of TG(P<0.001),TC(P<0.05),LDL-C(P<0.05).It was found that the composit probiotics could obviously reduce the liver fat in db/db diabetic mice.4.Composit probiotics can reduce 24h mALB and protect kidney tissue.5.Composit probiotics could significantly increase the number of four lactic acid bacteria and Lactobacillus and decrease the number of Escherichia in the intestine of db/db diabetic mice.Conclusion:Composit probiotics can improve the disorder of blood glucose and abnormal blood lipid in db/db diabetic mice and play an important role in protecting liver and kidney function and regulating intestinal microbiota of db/db diabetic mice.