Aim of study:Molecular mechanisms underlying the lipodystrophy associated metabolic syndrome remain unknown.Ap2-SREBP-1C transgenic mice overexpressing Nsrebp-1 c in adipose tissue under the control of the adipocyte-specific ap2 enhancer feature distinct adipose tissue disorders:barely existing WAT and compensatory hyperplasia of BAT,which contributes to dysfunction.As a result. ap2-SREBP-IC transgenic mice are characterized as models of type2 diabetes,hypercholesteremia and fatty liver.However,the relationship between imparing adipose function and insulin resistance needs to be further clarification.In this study,we aim to investigate the high food diet(HFD)effect on ap2-SREBP-IC mice.We want to observe whether BAT play a crucial role in IR.Material and methods:1 year old ap2-SREBP-lC transgenic mice and their littermates were randomly divided int0 4 groups:2 regular diet group(WT+RD group and TG+RD group) and 2 high fat diet group(WT+HFD group and TG+HFD group) lasting 6 months.The high fat diet consisted of 24% protein,41.0% carbohydrate,24.0% fat.During the experimental session,bodyweight gain,food-intake and water-intake were assayed every Thursday and Sunday.Tissue weigh of BAT.WAT.liver.muscle were calculated after dissection.Genes ACC.FAS in liver were determined by RT-PCR.Plasm levels of glucose,triglyceride,total cholesterol,free fatty acid,HDL-C,LDL-C,insulin,were determined using enzyme-linked immunosorbent assay.Levels of triglyceride,total cholesterol in liver and muscle were calculated by immunosorbent assay after homogenate.UCP-1 was detected by immunohistochemistry.Results:Our results indicated that compared to wildtype mice intaking HFD,BAT in ap2-SREBP-lc mice intaking HFD degenerated dramatically after 6 months HFD intake.BAT markers UCP-1 which is determined by immunohistochemistry expressed stronger.Weigh of WAT varies,weigh of liver in TG+HFD gains more than that in WT+HFD.Daily food intake.water intake and body weigh gain show no differences between each paired group.Levels of total cholesterol increased dramatically in TG+HFD group comparing to TG group,while TC show no differences between WT groups.Triglyceride increased after HFD inake in both WT and TG groups.There arent any accumulation of triglyceride and total cholesterol in muscle.Fasting plasma TC and HDL-C increased in TG+HFD.We also found increased level of CPTI/a in WT+HFD group,but reduced level in TG+HFD group,while compared to their control groups.ACC increased dramatically in TG+HFD group while only a litter in WT+HFD.Conclusions:Lipodystrohy related insulin resistance is closely related to BAT function.HFD intake can affect metabolic syndrome to some extent,whichBAT may play a crucial role.