Chinese Journal of Tissue Engineering Research ›› 2023, Vol. 27 ›› Issue (23): 3714-3720.doi: 10.12307/2023.487

Previous Articles     Next Articles

Mechanism by which aerobic endurance exercise regulates cardiomyocyte autophagy in rats

Liu Jihuan1, Wang Peng1, Yuan Shunling1, Jian Ye1, Huang Shaoze1, Yao Sisi1, Liu Wenfeng1, 2   

  1. 1Hunan Provincial Key Laboratory of Physical Fitness and Exercise Rehabilitation, Hunan Normal University, Changsha 410012, Hunan Province, China; 2Key Laboratory of Protein Chemistry and Developmental Biology, Ministry of Education, Hunan Normal University, Changsha 410081, Hunan Province, China
  • Received:2022-02-23 Accepted:2022-07-18 Online:2023-08-18 Published:2023-01-16
  • Contact: Liu Wenfeng, MD, Professor, Hunan Provincial Key Laboratory of Physical Fitness and Exercise Rehabilitation, Hunan Normal University, Changsha 410012, Hunan Province, China; Key Laboratory of Protein Chemistry and Developmental Biology, Ministry of Education, Hunan Normal University, Changsha 410081, Hunan Province, China
  • About author:Liu Jihuan, Master candidate, Hunan Provincial Key Laboratory of Physical Fitness and Exercise Rehabilitation, Hunan Normal University, Changsha 410012, Hunan Province, China
  • Supported by:
    the National Natural Science Foundation of China, No. 81702236 (to LWF); Key Project of Hunan Provincial Department of Education, No. 20A333 (to LWF); Natural Science Foundation of Hunan Province, No. 2018JJ3363 (to LWF); Hunan Province College Young Backbone Teacher Project, No. [2020]43 (to LWF); Hunan Provincial Postgraduate Research and Innovation Project, No. [2021]267 (to LJH); Young Talents Training Program of Hunan Normal University, No. ET1507 (to LWF)

PDF

76

Abstract: BACKGROUND: In recent years, studies on chronic diseases related to aging have attracted wide attention worldwide. As the heart grows with age, premature aging may occur. Exercise is a safe and healthy intervention that can delay its aging.
OBJECTIVE: To observe the effect of regular aerobic exercise on the aging of cardiomyocytes and explore its mechanism.
METHODS: Healthy male SPF Sprague-Dawley rats aged 3 months (young, n=20), 13 months (middle age, n=24), and 22 months (old, n=24) were randomly divided into youth rest group, youth exercise group, middle age rest group, middle age exercise group, old age rest group, and old age exercise group. The three resting groups did not do aerobic exercise intervention, and the three exercise groups were given a 10-week incremental load aerobic treadmill exercise consisting of 6-week incremental load exercise and 4-week constant load exercise. RT-PCR and immunohistochemical detection were used to detect myocardial Beclin-1, CaMKIIα1, AMPKα1/pAMPKα1, and PI3K/Akt/mTOR pathway-related proteins and genes. 
RESULTS AND CONCLUSION: After regular aerobic exercises, compared with the three resting groups, the expression levels of Beclin-1 in cardiomyocytes were significantly down-regulated in the three exercise groups. The expression levels of myocardial CaMKIIα1 mRNA were also down-regulated in the three exercise groups. The protein expression levels of pAMPKα1 and AMPKα1 in the three resting groups showed an aging trend, and the expression levels of AMPKα1 in the young, middle age, and old age exercise groups were up-regulated by 16.50% (P < 0.05), 63.09% (P < 0.05), and 31.12% (P < 0.01), respectively. The expression levels of pAMPKα1 were also significantly up-regulated by 131.29% in the young exercise group (P < 0.01), 40.55% in the middle age exercise group (P < 0.01), and 16.77% in the old age exercise group (P < 0.05). Overall, the expression levels of PI3K in the myocardium were down-regulated in the three exercise groups compared with the three resting groups, while the expression levels of AKT1 mRNA were down-regulated in the young and middle age exercise groups. The expression level of mTOR mRNA was slightly down-regulated in the young exercise group, little changed in the middle age exercise group, and significantly up-regulated in the old age exercise group. To conclude, aerobic exercise can significantly up-regulate the expression of PI3K, promote the activity of mTOR, down-regulate the expression of CaMKIIα1, down-regulate the ratio of pAMPKα1/AMPKα1, decrease the expression of Beclin-1, regulate the level of myocardial autophagy, and make it tend to be normal and stable in aged rats, thereby delaying myocardial aging.

Key words: regular aerobic exercise, myocardium, aging, autophagy, AMPK/pAMPK signaling pathway

CLC Number: