The Effects Of High-intensity Interval Training On Autophagy Signaling Pathway And Mitochondrial Complex In Skeletal Muscle Of Middle-aged Mice

The aim of study:The effects of HIIT on autophagy signaling pathway and mitochondrial complex protein of gastrocnemius muscle in middle aged mice were studied by establishing a long term HIIT exercise model in mice.Methods:Twelve middle-aged(12-month-old)healthy male ICR mice were randomly divided into a quiet control group(CON)and a exercise group(HIIT).The HIIT group of mice underwent 7 weeks of exercise training.At 48 hours after the end of the last training,the mouse gastrocnemius muscle tissue was extracted.Western blotting assay for autophagy-associated protein light chain 3(LC3),ubiquitin-binding protein 1(sequestosome 1,p62),and mitochondrial autophagy-associated protein Parkin,lysosome-associated membrane protein type 2a(Lamp2a)protein expression,AMP-dependent protein kinase(adenosine 5'-monophosphate(AMP)-activated protein kinase,AMPK/rametin target of rapamycin(mTOR)signaling pathway protein expression,mitochondrial complex I V(Mitochondrial complex I V,Complex I V)protein expression;gastrocnemius mitochondrial component autophagy-associated protein LC3,p62 protein expression.Results:1、Effects of high intensity interval training on expression of autophagy related proteins in gastrocnemius of middle aged miceThere was no significant change in the ratio of LC3 Ⅱ/LC3 Ⅰ in the HUT group compared with the CON group;the protein expression of p62 was significantly decreased(P<0.05).Parking protein expression was significantly increased(P<0.05).The protein expression of Lamp2 was significantly increased(P<0.001).2、Effects of high intensity interval training on expression of mitochondrial autophagy related proteins in gastrocnemius of middle aged miceCompared with the CON group,the protein expression of the LC3 Ⅱ/LC3 Ⅰ in the mitochondrial part of the gastrocnemius muscle of the HUT group did not change significantly;there was no significant change in the expression of p62 protein.3、Effects of high intensity interval training on AMPK/mTOR signaling pathway in gastrocnemius of middle aged miceCompared with the CON group,the protein expression of p AMPK/AMPK was significantly increased in the HIIT group(P<0.05).the protein expression of pmTOR/mTOR in the HIIT group was significantly decreased(P<0.01).4、Effects of high intensity interval training on the expression of mitochondrial complex protein in gastrocnemius of middle aged miceCompared with the CON group,the expression of Mitochondrial Complex Ⅱ、Ⅲand V proteins in the gastrocnemius muscle of the HIIT group was significantly increased(P<0.01,P<0.01,P<0.001).Conclusions:1、High intensity interval training may activate autophagy in the gastrocnemius of middle aged mice through the AMPK/mTOR signaling pathway.2、High intensity interval training can increase the expression of mitochondrial complex protein in the gastrocnemius of middle aged mice.