The lowered Lipids Efficiency of Metformin in Fat-fed,Streptozotocin-Treated Rats

Objective To investigate the lowered lipid efficiency of Metformin(Met)on glycometabolism in fat-fed, streptozotocin-treated diabetic rats (Fat-fed/STZ rats). Methods The rat model of type 2 diabetes was established. Male Wistar rats adapted surrounding for a week,then they randomly divided into normal control group(NC group) and model groups that were randomly divided into 3 groups:diabetes control group(DC group), Metgroups(200mg·kg-1) and Lovastatin group (4mg · kg-1)-NC rats were fed conventional chow for seven weeks and then injected with vehicle of 0.1mol/L citric acid buffer (pH 4.5);while model rats were fed high-fat diet (30% of calories as fat) for seven weeks and then injected with streptozotocin (STZ,20mg·kg-1, via the caudal vein once). After two weeks of STZ treatment, all groups were administered daily by gavage for a months.NC group and MC group were administered with 0.1 mol/L citric acid buffer.Then the effects of Met on fast blood glucose,insulin and lipids concentrations in fat-fed,strepotozotocin-treated diabetic rats was studied.Results Before Met administered, all Fat-fed/STZ groups had higher glucose concentrations to NC group,and significantly higher triglyceride (TG), total cholesterin (TC), low-density lipoprotein (LDL-C), high-density lipoprotein (HDL-C). Met (administered for a month) reduced TG (P0.01), TC (P0.01), LDL-C (P0.01) and increased HDL-C (P0.05) in Met groups compared with DC group. Met groups had a somewhat lower glucose and insulin concentrations, but had significantly higher insulin sensitivity index (ISI) (P0.01) to DC group.Conclusions Met can correct the hyperlipidemia and improve insulin resistance in fat-fed, streptozotocin-induced diabetic rats.