0bjective:To confirm the role of decreased chemerin on aerobic exercise-induced improvement of glucose and lipid metabolism using exogenous chemerin in obese,diabetic and atherosclerotic rats,and to explore whether the mechanisms is related to the key enzymes or proteins of glucose and lipid metabolism mediated by peroxi-some proliferator-activated receptor γ(PPARγ)in the peripheral metabolic organs(liver,muscle and fat),includ-ing lipoprotein triglyceride lipase(ATGL)and lipoprotein lipase(LPL)and glucose transporter 4(GLUT4). Method:①Animal experiments:Total of 130 male rats aged 6 weeks were included in this study.In addition to the normal control(Con,n=17)rats,the model rats with obesity(OB),atherosclerosis(AS)and diabetes mellitus(DM)were established by 8-week high-fat diet,8-week high-fat diet combined with intraperitoneal injection of Vitamin D3 or of low dose of streptozotocin,respectively.All the successfully established model rats were ran-domly divided into:the control[AS(n=8),OB(n=8)and DM(n=10)and the exercise(EAS(n=8),EOB(n=8)and EDM(n=10)]rats.All exercise groups were participated in the 4-week moderate-intensity treadmill running exercise with gradually increased load,six days per week and one time per day.Serum chemerin were detect-ed by ELISA.Protein levels of chemerin,CMKLR1,PPARγ,ATGL,LPL and GLUT4 in tissues(liver,gastrocne-mius and perirenal fat)were detected by Western blot.In order to confirm the mediation role of PPARγ,diabet-ic rats were randomly divided into 4 groups:DM(n=10),EDM(n=10),EDM plus PPARγ agonist pioglitazone(EDP,n=10)and EDM plus PPARγ antagonist GW9662(EDG,n=10),and the protein levels of ATGL,LPL and GLUT4 were detected.②Cell experiments:3T3-L1 cells were treated with exogenous chemerin(200 ng/ml)for 48 h,then the cells were collected to detect the protein levels of PPARγ,ATGL,LPL and GLUT4. Result:①The serum chemerin and the protein levels of chemerin and CMKLR1 in tissues(liver,gastrocnemius and perirenal fat)of EAS,EOB and EDM groups rats were significantly decreased after 4-week aerobic exer-cise,with the improvement of blood glucose and lipid.The protein levels of PPARγ,ATGL,LPL in liver,gas-trocnemius and perirenal fat,and GLUT4 in gastrocnemius were significantly increased in the EAS,EOB and EDM rats after 4-week aerobic exercise.② In DM rats,the increase of ATGL,LPL and GLUT4 induced by aerobic exercise were partially reversed by PPARγ inhibitor GW9662 and further enhanced by PPARγ agonist pioglitazone.(3)The protein levels of PPARγ,ATGL,LPL and GLUT4 in 3T3-L1 cells were significantly re-duced after treating the cells with exogenous chemerin. Conclusion:The improved effect of 4 weeks of aerobic exercise on blood glucose and blood lipid in rats with obesity,diabetic and atherosclerosis is related to the reduction of chemerin,thereby upregulating key en-zymes and proteins of glycolipid metabolism(including ATGL,LPL and GLUT4).The effect of chemerin on the above key enzymes and protein is mediated by PPARγ in diabetes rats.