利拉鲁肽对ob/ob小鼠骨骼肌胰岛素抵抗的影响和相关机制研究  

Effects of liraglutide on insulin resistance in skeletal muscle of ob/ob mice and the underlying mechanisms

作　　者：徐志凯 高歌 赵丽华 高宇[2] 郭晓宇[2] 邢恩鸿[3] Xu Zhikai;Gao Ge;Zhao Lihua;Gao Yu;Guo Xiaoyu;Xing Enhong(Graduate School of Chengde Medical University,Chengde 067000,China;Department of Endocrinology,Affiliated Hospital of Chengde Medical University,Hebei Key Laboratory of Panvascular Diseases,Chengde 067000,China;Central Laboratory,Affiliated Hospital of Chengde Medical University,Chengde 067000,China)

机构地区：[1]承德医学院研究生学院,承德067000 [2]承德医学院附属医院内分泌科,河北省泛血管疾病重点实验室,承德067000 [3]承德医学院附属医院中心实验室,承德067000

出　　处：《中华糖尿病杂志》2024年第12期1411-1417,共7页CHINESE JOURNAL OF DIABETES MELLITUS

基　　金：河北省自然科学基金(C2022406011);河北省研究生创新能力培养资助项目(CXZZSS2024120);承德市生物医药产业研究院建设项目(202205B086)。

摘　　要：目的探讨利拉鲁肽对ob/ob小鼠骨骼肌胰岛素抵抗的影响,并探讨骨骼肌应激诱导蛋白2(Sesn2)/腺苷酸活化蛋白激酶(AMPK)、自噬因子表达及与胰岛素抵抗的相关性。方法将30只雄性7周龄ob/ob小鼠按照随机数字表法分为3组:ob/ob小鼠组(Ob组)、高脂喂养组(Ob+HFD组)和利拉鲁肽组(Ob+HFD+Lir组),每组10只,另将10只雄性C57BL/6J小鼠作为正常对照组(NC组),NC、Ob及Ob+HFD组小鼠腹腔注射生理盐水,Ob+HFD+Lir组小鼠腹腔注射利拉鲁肽注射液400μg·kg^(-1)·d^(-1),适应性喂养1周,随后干预5周。检测各组小鼠体重,并进行口服葡萄糖耐量实验(OGTT),透射电镜观察腓肠肌形态和自噬小体数量,Western blotting检测小鼠腓肠肌组织中Sesn2、AMPK、磷酸化的AMPK(p-AMPK)、螯合体1(P62)、微管相关蛋白1轻链3Ⅰ(LC3Ⅰ)、微管相关蛋白1轻链3Ⅱ(LC3Ⅱ)、蛋白激酶B(AKT)、磷酸化的AKT(p-AKT)及葡萄糖转运蛋白4(GLUT4)蛋白的表达。组间比较采用单因素方差分析。结果与NC组比较,Ob组和Ob+HFD组小鼠体重及OGTT时间-血糖曲线的曲线下面积(AUC)增加,与Ob组比较,Ob+HFD组体重及AUC增加,与Ob+HFD组比较,Ob+HFD+Lir组小鼠体重和AUC降低,差异均有统计学意义[NC组、Ob组、Ob+HFD组、Ob+HFD+Lir组AUC分别为(1196.0±136.5)、(1573.0±117.4)、(1781.0±193.6)、(1312.0±140.8)mmol·L^(-1)·min^(-1),P<0.05]。与NC组比较,Ob组和Ob+HFD组透射电镜观察小鼠腓肠肌组织自噬小体数量减少,肌组织损伤,胞质局部水肿,肌原纤维局部断裂,肌丝粗细不一;与Ob组比较,Ob+HFD组腓肠肌组织自噬小体数量进一步减少,肌组织损伤更明显,胞质水肿,肌原纤维排列紊乱,细胞器肿胀,而Ob+HFD+Lir组小鼠腓肠肌自噬小体数量增加,肌组织损伤较轻,胞质略浅、变淡,细胞器轻度肿胀,肌原纤维少量断裂,差异具有统计学意义(P<0.05)。与NC组比较,Ob组和Ob+HFD组小鼠腓肠肌Sesn2、GLUT4蛋白表达降低,p-AMPK/AMPK、LC3Ⅱ/LCObjective To investigate the effects of liraglutide on insulin resistance in the skeletal muscle of ob/ob mice,and to explore the correlation between the expression of sestrin2/adenosine monophosphate-activated protein kinase(Sesn2/AMPK),autophagy factors and insulin resistance.Methods Thirty male 7-week-old ob/ob mice were randomly divided into three groups:ob/ob mice group(Ob group,n=10),high-fat diet group(Ob+HFD group,n=10),and liraglutide group(Ob+HFD+Lir group,n=10).In addition,10 male C57BL/6J mice were used as the normal control group(NC group).Mice in the NC,Ob,and Ob+HFD groups were injected intraperitoneally with normal saline,while mice in the Ob+HFD+Lir group were injected intraperitoneally with liraglutide injection at a dose of 400μg·kg^(-1)·d^(-1).After one week of adaptive feeding,the intervention lasted for 5 weeks.Mouse body weight was measured,oral glucose tolerance test(OGTT)was performed,transmission electron microscopy was used to observe the morphology of gastrocnemius muscle and the number of autophagosomes,and Western blotting was used to detect the expression of Sesn2,AMPK,phosphorylated AMPK(p-AMPK),sequestosome 1(P62),microtubule-associated protein 1 light chain 3Ⅰ(LC3Ⅰ),microtubule-associated protein 1 light chain 3Ⅱ(LC3Ⅱ),protein kinase B(AKT),phosphorylated AKT(p-AKT),and glucose transporter 4(GLUT4)proteins in mouse gastrocnemius muscle tissue.One-way analysis of variance(ANOVA)was used to compare between groups.Results Compared with the NC group,the body weight and the area under the curve(AUC)of the time-blood glucose curve during OGTT increased in the Ob and Ob+HFD groups.Compared with the Ob group,the body weight and AUC increased in the Ob+HFD group.Compared with the Ob+HFD group,the body weight and AUC decreased in the Ob+HFD+Lir group,with statistically significant differences[NC group AUC(1196.0±136.5)mmol·L^(-1)·min^(-1),Ob group AUC(1573.0±117.4)mmol·L^(-1)·min^(-1),Ob+HFD group AUC(1781.0±193.6)mmol·L^(-1)·min^(-1),Ob+HFD+Lir group AUC(1312.0±140.8)

关 键 词：利拉鲁肽 应激诱导蛋白 一磷酸腺苷活化蛋白激酶 骨骼肌 自噬 胰岛素抵抗 

分 类 号：R587.1[医药卫生—内分泌]