CAJ | 학술논문

目的：探讨耐力运动对营养性肥胖小鼠骨骼肌细胞自噬及线粒体自噬的影响及其分子机制。方法：采用6周高脂膳食干预诱导生长期ICR雄性小鼠营养性肥胖模型,建模成功后随机分为高脂膳食对照组（HC,6只）、普通膳食干预组（HN,6只）及普通膳食联合耐力运动干预组（HNE,6只）,另选造模对照ICR小鼠为普通膳食对照组（NC,6只）,HC组小鼠持续喂养6周高脂膳食,NC、HN、HNE饲以普通膳食,HNE组小鼠进行6周跑台耐力训练,速度按周递增即15m/min、22m/min、27 m/min、31 m/min、35 m/min、35 m/min,40 min/次,6次/周。末次训练24h后处死小鼠并采样,应用JC-1探针法检测线粒体膜电位,RT-PCR及Western Blotting技术检测相关基因及蛋白表达情况。结果：1）6周高脂膳食可诱导小鼠体重、LEE’s指数及附睾脂肪百分比显著增加（P〈0.05）,BG、TG、TC、HDL-C、LDL-C含量显著增加（P〈0.05）;2）与HC比,HNE组骨骼肌MHCⅠ、Ⅱa、Ⅱc表达均显著增加（P〈0.05）,HN、HNE组MHCⅡb mRNA表达均下调;3）与NC比,HC组骨骼肌线粒体膜电位显著降低（P〈0.05）,HC、HN、HNE组小鼠骨骼肌mtDNA拷贝数量下降（P〈0.05）;4）与NC组比,HC组小鼠细胞自噬相关信号分子ATG 13、LC3 mRNA表达下调,P62 mRNA表达上调;HN、HNE组BECN1、ATG 13及LC3mRNA含量显著增加（P〈0.05）,HC组LC3Ⅱ/Ⅰ比值下降,HN、HNE组小鼠骨骼肌p62蛋白水平下降,HNE组LC3Ⅱ/Ⅰ比值上调;5）HC组NIX mRNA表达与NC组比下调,而在HN、HNE组含量增加;HNE组PARK2、PARL mRNA较HN组上调;HC组PINK1蛋白含量有所下调,而在HN及HNE组普遍上调（P〈0.05）。结论：1）长期高脂膳食干预可诱导营养性肥胖发生,引起机体代谢紊乱、骨骼肌线粒体功能异常;2）耐力运动结合膳食改善可有效控制营养性肥胖小鼠体重并促进肌球蛋白的表达;3）耐力运动结合膳食改善可缓解营养性肥胖机体细胞自噬水平的下降,而对线粒体自噬的影响主要通过作用于PINK1/Parkin信号以调控骨骼肌线粒体的数量和功能。目的：探討耐力運動對營養性肥胖小鼠骨骼肌細胞自噬及線粒體自噬的影響及其分子機製。方法：採用6週高脂膳食榦預誘導生長期ICR雄性小鼠營養性肥胖模型,建模成功後隨機分為高脂膳食對照組（HC,6隻）、普通膳食榦預組（HN,6隻）及普通膳食聯閤耐力運動榦預組（HNE,6隻）,另選造模對照ICR小鼠為普通膳食對照組（NC,6隻）,HC組小鼠持續餵養6週高脂膳食,NC、HN、HNE飼以普通膳食,HNE組小鼠進行6週跑檯耐力訓練,速度按週遞增即15m/min、22m/min、27 m/min、31 m/min、35 m/min、35 m/min,40 min/次,6次/週。末次訓練24h後處死小鼠併採樣,應用JC-1探針法檢測線粒體膜電位,RT-PCR及Western Blotting技術檢測相關基因及蛋白錶達情況。結果：1）6週高脂膳食可誘導小鼠體重、LEE’s指數及附睪脂肪百分比顯著增加（P〈0.05）,BG、TG、TC、HDL-C、LDL-C含量顯著增加（P〈0.05）;2）與HC比,HNE組骨骼肌MHCⅠ、Ⅱa、Ⅱc錶達均顯著增加（P〈0.05）,HN、HNE組MHCⅡb mRNA錶達均下調;3）與NC比,HC組骨骼肌線粒體膜電位顯著降低（P〈0.05）,HC、HN、HNE組小鼠骨骼肌mtDNA拷貝數量下降（P〈0.05）;4）與NC組比,HC組小鼠細胞自噬相關信號分子ATG 13、LC3 mRNA錶達下調,P62 mRNA錶達上調;HN、HNE組BECN1、ATG 13及LC3mRNA含量顯著增加（P〈0.05）,HC組LC3Ⅱ/Ⅰ比值下降,HN、HNE組小鼠骨骼肌p62蛋白水平下降,HNE組LC3Ⅱ/Ⅰ比值上調;5）HC組NIX mRNA錶達與NC組比下調,而在HN、HNE組含量增加;HNE組PARK2、PARL mRNA較HN組上調;HC組PINK1蛋白含量有所下調,而在HN及HNE組普遍上調（P〈0.05）。結論：1）長期高脂膳食榦預可誘導營養性肥胖髮生,引起機體代謝紊亂、骨骼肌線粒體功能異常;2）耐力運動結閤膳食改善可有效控製營養性肥胖小鼠體重併促進肌毬蛋白的錶達;3）耐力運動結閤膳食改善可緩解營養性肥胖機體細胞自噬水平的下降,而對線粒體自噬的影響主要通過作用于PINK1/Parkin信號以調控骨骼肌線粒體的數量和功能。
목적：탐토내력운동대영양성비반소서골격기세포자서급선립체자서적영향급기분자궤제。방법：채용6주고지선식간예유도생장기ICR웅성소서영양성비반모형,건모성공후수궤분위고지선식대조조（HC,6지）、보통선식간예조（HN,6지）급보통선식연합내력운동간예조（HNE,6지）,령선조모대조ICR소서위보통선식대조조（NC,6지）,HC조소서지속위양6주고지선식,NC、HN、HNE사이보통선식,HNE조소서진행6주포태내력훈련,속도안주체증즉15m/min、22m/min、27 m/min、31 m/min、35 m/min、35 m/min,40 min/차,6차/주。말차훈련24h후처사소서병채양,응용JC-1탐침법검측선립체막전위,RT-PCR급Western Blotting기술검측상관기인급단백표체정황。결과：1）6주고지선식가유도소서체중、LEE’s지수급부고지방백분비현저증가（P〈0.05）,BG、TG、TC、HDL-C、LDL-C함량현저증가（P〈0.05）;2）여HC비,HNE조골격기MHCⅠ、Ⅱa、Ⅱc표체균현저증가（P〈0.05）,HN、HNE조MHCⅡb mRNA표체균하조;3）여NC비,HC조골격기선립체막전위현저강저（P〈0.05）,HC、HN、HNE조소서골격기mtDNA고패수량하강（P〈0.05）;4）여NC조비,HC조소서세포자서상관신호분자ATG 13、LC3 mRNA표체하조,P62 mRNA표체상조;HN、HNE조BECN1、ATG 13급LC3mRNA함량현저증가（P〈0.05）,HC조LC3Ⅱ/Ⅰ비치하강,HN、HNE조소서골격기p62단백수평하강,HNE조LC3Ⅱ/Ⅰ비치상조;5）HC조NIX mRNA표체여NC조비하조,이재HN、HNE조함량증가;HNE조PARK2、PARL mRNA교HN조상조;HC조PINK1단백함량유소하조,이재HN급HNE조보편상조（P〈0.05）。결론：1）장기고지선식간예가유도영양성비반발생,인기궤체대사문란、골격기선립체공능이상;2）내력운동결합선식개선가유효공제영양성비반소서체중병촉진기구단백적표체;3）내력운동결합선식개선가완해영양성비반궤체세포자서수평적하강,이대선립체자서적영향주요통과작용우PINK1/Parkin신호이조공골격기선립체적수량화공능。
Objective：To determine the effect of endurance exercise on cellular autophagy and mi- tophagy in skeletal muscle of obese mice and explore the underlying molecular mechanism. Methods ： After the alimentary obesity ICR mice modle constrction, the obese mice were ran- domly divided into high-fat diet control group （HC, n= 6）, normal diet amelioration group （HN, n= 6） and normal diet combined with endurance exercise group （lINE, n = 6）. The mice of normal diet control group during the constretion of alimentary obesity model were assigned as the normal control group （NC, n= 6）. The mice in groups NC, HN and HNE were fed with nomal diet while the mice of group HC were fed with high fat diet . The mice of group HNE underwent treadmill running for 6 weeks, 45rain/d, 6 times per week. Results ： 1） Fiigh-fat diet for 6 week increased the body weight, Lee＇s index and epididymal fat percentage of mice, while a series of blood index such as BG, TG, TC, HDL-C and LDL-C increased sig- nificantly. 2） The relative contents of myosin heavy chain Ⅰ , Ⅱ a and Ⅱ c mRNA were upregulated in group HNE, compared with group EC. 3） The mitochondrial membrance potential of skeletal muscle in group HC was lower than that of group NC, while the mtDNA relative content in group HC, HN and FINE were lower than NC. 4） Compared to NC, the autophagy related genes ATG13 and LC3 mRNA decreased while P62 mRNA expression level increased; the BECN1, ATG13 and LC3 mRNA relative content of FIN and HNE were higher than thosein HC （P〈0.05） and the ratio of LC3 Ⅱ / Ⅰof HNE increased in skeletal muscle compared with HC. 5 ） The mitophagy related gene NIX mRNA expression was lower in HC compared to that of NC,whereas it accerlarated in group HN and HNE; in group HNE, the PARK2 and PARL mRNA relative content increased compared to HN; the protein content of PINK ldown- regulated in HC and up-regulated obviously in group HN and HNE（P〈0.05）. Conclusion： 1 ） Long-term high-fat-diet intervention can lead to alimentary obesity accompanied with meta- bolic disorders and mitochondrial dysfunction in the skeletal muscle. 2 ） Endurance exercise combined with dietary intervention can effectively slow down the weight gain and increase the protein expression of myosin heavy chain in the alimentarily obese mice. 3 ） Endurance exercise combined with dietary intervention can obviously attenuate the decline of autophagy level in duced by high-fat-diet as well as maintain the quality and function of mitochondria in skeletal muscle, in which the mitophagy related PINK1/Parkin singnaling pathway involves and plays a crititial role.