二氢杨梅素对高脂饮食诱导的小鼠肥胖的影响及其机制

目的:观察二氢杨梅素(DHM)对高脂饮食诱导小鼠肥胖的影响,并探讨其作用机制是否与促进WAT棕色化有关。方法:60只c57bl/6j小鼠随机分为6组(n=10):①正常对照组(ND组):普通饲料喂养、②正常对照+低剂量DHM组(ND+L-DHM组):普通饲料喂养同时用低剂量DHM(125 mg/(kg·d))处理、③正常对照+高剂量DHM组(ND+H-DHM组):普通饲料喂养同时用高剂量DHM(250 mg/(kg·d))处理、④高脂饮食组(HFD):高脂饲料喂养、⑤高脂饮食+低剂量DHM组(HFD+L-DHM组):高脂饲料喂养同时用低剂量DHM处理、⑥高脂饮食+高剂量DHM组(HFD+H-DHM组):高脂饲料喂养同时用高剂量DHM处理。16周后小鼠空腹过夜,取血测空腹血糖和血脂,随后处死动物,测体长,算出Lee's指数;取肩胛下、腹股沟和附睾处脂肪组织称重后,甲醛固定、HE染色观察脂肪细胞大小,免疫组化检测解偶联蛋白1(UCP1)的表达;实验期间每4周测一次小鼠体重。结果:与ND组相比较,HFD组小鼠体重显著升高,提示肥胖小鼠模型复制成功。此外,HFD组小鼠体脂重量、脂肪细胞直径、Lee's指数和血糖显著增加、脂肪细胞UCP1的表达升高;使用L-DHM和H-DHM处理HFD小鼠后,体脂重量、脂肪细胞直径、Lee's指数和血糖等指标显著逆转,而脂肪细胞UCP1的表达升高更为显著;但L-DHM和H-DHM对正常小鼠上述指标无显著影响。结论:二氢杨梅素抑制高脂饮食诱导的小鼠肥胖,其机制可能与促进WAT棕色化有关。

Effects of dihydromyricetin on high fat diet induced obesity in mice and its mechanism

Objective:To observe the effects of dihydromyricetin(DHM)on obesity induced by high-fat diet in mice,and to explore whether its mechanism of action is related to the promotion of WAT browning.Methods:Sixty c57bl/6j mice were randomly divided into 6 groups(n=10):①normal control group(ND group):normal feed feeding;②Normal control+low dose DHM group(ND+L-DHM group):normal feed feeding was treated with low dose DHM(125 mg/(kg·d));③Normal control+high dose DHM group(ND+H-DHM group):normal feed feeding was treated with high dose DHM(250 mg/(kg·d));④High-fat diet group(HFD):high-fat diet;⑤high-fat diet+low-dose DHM group(HFD+L-DHM group):high-fat diet feeding with low-dose DHM;⑥High-fat diet+high-dose DHM group(HFD+H-DHM group):High-fat diet was treated with high-dose DHM.After 16 weeks,the mice were fasted overnight,blood samples were collected for fasting blood glucose and blood lipids,then the animals were sacrificed,body length was measured,and Lee's index was calculated.After weighing the adipose tissue in the scapula,groin and epididymis,formaldehyde fixation and HE staining were used to observe the fat cells size,immunohistochemistry was used to detect the expression of uncoupling protein 1(UCP1).The body weight was measured every 4 weeks during the experiment.Results:Compared with the ND group,the body weight of the mice in the HFD group was increased significantly,suggesting that the obese mouse model replicated successfully.In addition,the body fat weight,fat cell diameter,Lee's index and blood glucose of the HFD group were increased significantly,and the expression of UCP1 in the adipocytes was increased.Body weight,fat cell diameter,Lee's index and blood glucose of HFD mice treated with L-DHM and H-DHM were reversed significantly,while the expression of UCP1 in adipocytes was more significantly increased;however,L-DHM and H-DHM had no significant effects on the above indicators in normal mice.Conclusion:Dihydromyricetin inhibited high fat diet induced mouse obesity;the mechanism might be associated with promoting WAT browning.