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Pirani H, Soltany A, Hossein Rezaei M, Khodabakhshi Fard A, Nikooie R, Khoramipoor K, Chamari K, Khoramipour K. Lactate-induced autophagy activation: unraveling the therapeutic impact of high-intensity interval training on insulin resistance in type 2 diabetic rats. Sci Rep 2024; 14:1108. [PMID: 38212600 PMCID: PMC10784291 DOI: 10.1038/s41598-023-50589-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 12/21/2023] [Indexed: 01/13/2024] Open
Abstract
Impaired autophagy is a hallmark of diabetes. The current study proposed to investigate if high intensity interval training (HIIT) induced lactate accumulation could stimulate autophagy in type 2 diabetic male rats. 28 male Wistar rats were randomly assigned into four groups: Healthy Control (CO), Diabetes Control (T2D), Exercise (EX), and Diabetes + Exercise (T2D + EX). Diabetes was induced by feeding high-fat diet and administrating single dose of streptozotocin (35 mg/kg). After becoming diabetic, the animals in the exercise groups (EX and T2D + EX) performed an eight-week HIIT (4-10 interval, 80-100% Vmax, 5 days per week). Serum levels of lactate, glucose and insulin as well as the levels of lactate, pyruvate, lactate transporter monocarboxylate transporter 1 (MCT1), phosphorylated mitogen-activated protein kinases (p-MAP 1 and 2), phosphorylated extracellular signal-regulated protein kinases 1 and 2 (p-ERK 1 and 2), mammalian target of rapamycin (p-mTOR), ribosomal protein S6 kinase beta-1 (p-70S6k), p90 ribosomal S6 kinases (p-90RSK), autophagy related 7 (ATG7), Beclin-1, microtubule-associated protein 1A/1B, and 2A/2B -light chain 3 levels (LC3-I), (LC3- II), (LC3I/LC3II) in soleus muscle were measured. Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) and serum glucose was lower in T2D + EX compared to T2D group (P < 0.0001). While serum and soleus muscle levels of lactate was not different between T2D and T2D + Ex, the levels of Pyruvate (P < 0.01), MCT1, p-ERK1/2, p-mTOR, p70S6k, P-90RSK, ATG7, LC3-II, and LC3-II/LC3I ratios were higher in T2D + EX compared to T2D group (P < 0.0001). We concluded that eight weeks of high-intensity interval training could activated ERK/P90SRK while inhibiting mTOR/P70S6K signaling pathway in lactate dependent manner. It means increased autophagy which resulted in improve insulin resistance (IR) and reduce blood glucose.
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Affiliation(s)
- Hossein Pirani
- Department of Basic Sciences, Chabahar Maritime University, Chabahar, Iran
| | - Afsaneh Soltany
- Department of Biology, Faculty of Science, University of Shiraz, Shiraz, Iran
| | - Maryam Hossein Rezaei
- Department of Exercise Physiology, Faculty of Physical Education and Sport Sciences, Shahid Bahonar University, Kerman, Iran
| | - Adeleh Khodabakhshi Fard
- Department on Nutrition, Faculty of Public Health, Kerman University of Medical Sciences, Kerman, Iran
| | - Rohollah Nikooie
- Department of Exercise Physiology, Faculty of Physical Education and Sport Sciences, Shahid Bahonar University, Kerman, Iran
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Kimya Khoramipoor
- Department of Nursing, Faculty of Nursing and Midwifery, Kurdistan University of Medical Sciences, Kurdistan, Iran
| | - Karim Chamari
- Higher Institute of Sport and Physical Education, ISSEP Ksar Said, Manouba University, Manouba, Tunisia
| | - Kayvan Khoramipour
- Neuroscience Research Center, Institute of Neuropharmacology and Department of Physiology and Pharmacology, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran.
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Guo YP, Pan SS, Chen TR, Huang Y, Wan DF, Tong YS. Exercise preconditioning promotes myocardial GLUT4 translocation and induces autophagy to alleviate exhaustive exercise-induced myocardial injury in rats. J Mol Histol 2023; 54:453-472. [PMID: 37715078 DOI: 10.1007/s10735-023-10152-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 09/03/2023] [Indexed: 09/17/2023]
Abstract
Exercise preconditioning (EP) is a line of scientific inquiry into the short-term biochemical mediators of cardioprotection in the heart. This study examined the involvement of autophagy induced by energy metabolism in myocardial remodelling by EP and myocardial protection. A total of 120 healthy male Sprague Dawley (SD) rats were randomly divided into six groups. Plasma cTnI, HBFP staining and electrocardiographic indicators were examined in the context of myocardial ischemic/hypoxic injury and protection. Western blotting and fluorescence double labelling were used to investigate the relationship between energy metabolism and autophagy in EP-resistant myocardial injury caused by exhaustive exercise. Compared with those in the C group, the levels of myocardial ischemic/hypoxic injury were significantly increased in the EE group. Compared with those in the EE group, the levels of myocardial ischemic/hypoxic injury were significantly decreased in the EEP + EE and LEP + EE groups. Compared with that in the EE group, the level of GLUT4 in the sarcolemma was significantly increased, and the colocalization of GLUT4 with the sarcolemma was significantly increased in the EEP + EE and LEP + EE groups (P < 0.05). LC3-II and LC3-II/LC3-I levels of the EEP + EE group were significantly elevated compared with those in the EE group (P < 0.05). The levels of p62 were significantly decreased in the EEP + EE and LEP + EE groups compared with the EE group (P < 0.05). EP promotes GLUT4 translocation and induced autophagy to alleviate exhaustive exercise-induced myocardial ischemic/hypoxic injury.
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Affiliation(s)
- Yuan-Pan Guo
- Shanghai University of Sport, 399 Changhai Road, Shanghai, 200438, China
| | - Shan-Shan Pan
- Shanghai University of Sport, 399 Changhai Road, Shanghai, 200438, China.
| | - Tian-Ran Chen
- Shanghai University of Sport, 399 Changhai Road, Shanghai, 200438, China
| | - Yue Huang
- Shanghai University of Sport, 399 Changhai Road, Shanghai, 200438, China
| | - Dong-Feng Wan
- Shanghai University of Sport, 399 Changhai Road, Shanghai, 200438, China
| | - Yi-Shan Tong
- Shanghai University of Sport, 399 Changhai Road, Shanghai, 200438, China
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Santosa I, Shoji H, Arai Y, Awata K, Tokita K, Shimizu T. Hepatic and Skeletal Muscle Autophagy Marker Levels in Rat Models of Prenatal and Postnatal Protein Restriction. Nutrients 2023; 15:3058. [PMID: 37447384 DOI: 10.3390/nu15133058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 06/29/2023] [Accepted: 07/01/2023] [Indexed: 07/15/2023] Open
Abstract
Fetal growth restriction (FGR) leads to adult-onset metabolic syndrome. Intrauterine and early postnatal caloric restriction ameliorates the risk in animal models. To understand the underlying mechanism, we compared autophagic marker levels between offspring with FGR and those with prenatal and early postnatal protein restriction (IPPR). We postulated that FGR would impair, whereas IPPR would help regulate, autophagy in neonatal rats. This study involved control (Con), FGR offspring (Pre), and IPPR offspring groups (Pre + Post); n = 5/group. We assessed the abundance of autophagy markers in the liver and skeletal muscles. At birth, the Pre group pups had lower levels of some autophagy-related proteins, with increased p62 expression and a low microtubule-associated protein light chain beta (LC3-II:LC3-I) ratio. This finding suggests a lower hepatic autophagy flux in FGR offspring than the Con group. The hepatic levels of autophagy proteins were considerably decreased in the Pre and Pre + Post groups at 21 days of age compared to the Con group, but the LC3-II:LC3-I ratio was higher in the Pre + Post group than in the Con and Pre groups. The muscle levels of beclin-1, LC3-II, and p62 were lower in the Pre group pups, with no difference in the LC3-II:LC3-I ratio among the groups. An imbalance in the nutritional environment is associated with downstream autophagic flux, thus suggesting that FGR offspring will have impaired autophagic flux, and that post-natal nutrition restriction might help reduce this risk.
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Affiliation(s)
- Irena Santosa
- Department of Pediatrics and Adolescent Medicine, Graduate School of Medicine, Juntendo University, Bunkyo, Tokyo 113-8421, Japan
| | - Hiromichi Shoji
- Department of Pediatrics, Faculty of Medicine, Juntendo University, Bunkyo, Tokyo 113-8421, Japan
| | - Yoshiteru Arai
- Department of Pediatrics, Faculty of Medicine, Juntendo University, Bunkyo, Tokyo 113-8421, Japan
| | - Kentaro Awata
- Department of Pediatrics, Faculty of Medicine, Juntendo University, Bunkyo, Tokyo 113-8421, Japan
| | - Kazuhide Tokita
- Department of Pediatrics, Faculty of Medicine, Juntendo University, Bunkyo, Tokyo 113-8421, Japan
| | - Toshiaki Shimizu
- Department of Pediatrics and Adolescent Medicine, Graduate School of Medicine, Juntendo University, Bunkyo, Tokyo 113-8421, Japan
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Tao Z, Lin R, Zhang R, He P, Lei C, Li Y. Ischemia reperfusion myocardium injuries in type 2 diabetic rats: Effects of ketamine and insulin on LC3-II and mTOR expression. Int J Immunopathol Pharmacol 2023; 37:3946320231196450. [PMID: 37643354 PMCID: PMC10467302 DOI: 10.1177/03946320231196450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 08/03/2023] [Indexed: 08/31/2023] Open
Abstract
Objectives: Myocardiopathy occurs in ischemia-induced injury caused by dysregulation of autophagy of cardiac tissues. The present report evaluates the protective effect of ketamine and insulin against myocardial injury in type 2 diabetic rats (T2DM).Methods: The effects of ketamine and its combination with insulin on biochemical parameters and inflammatory cytokines in the serum of I/R-induced myocardial injury in T2DM rats were evaluated. The parameters of reactive oxygen species and the expression of autophagosome signaling pathway proteins were also determined. Using transmission electron microscopy, we investigated autophagosomes. Western blots were used to detect autophagy-associated signaling pathways. Myocardial function was determined by echocardiography and histopathological changes in myocardial tissues were also determined in I/R-induced myocardial injury in type 2 diabetic rats.Results: There was a significant reduction in glucose, AST, LDH, and CK-MB levels and cytokines (IL-1β, IL-6, and TNF-α) in serum of the ketamine (p < .05) and ketamine + insulin (p < .01) groups than in the diabetic + I/R. MDA and ROS levels were reduced with a substantial (p < .05) increase in GSH levels through improved cardiac function in the ketamine (p < .05) and ketamine + insulin (p < .01) groups than the diabetic + I/R group. There was an increase in mature autophagosomes in diabetic+I/R+Kt+In compared to diabetic+I/R+Kt alone in infarction and marginal zones. It should be noted that the significant increase (p < .01) in protein levels of the autophagy-associated intracellular signaling pathways AMPK and mTOR, as well as an increase in LC3-II and BECLIN-1, suggests that ketamine combined with insulin-activated autophagy-associated intracellular signaling AMPK and mTOR.Conclusion: The findings of the study suggest that ketamine combined with insulin administration remarkably protects I/R-induced myocardial injury in rats with T2DM by reducing the dysregulation of autophagy.
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Affiliation(s)
- Zhiguo Tao
- Department of Anaesthesiology, Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Rongmu Lin
- Department of Anaesthesiology, Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Rui Zhang
- Department of Anaesthesiology, Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Peng He
- Department of Anaesthesiology, Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Chengwen Lei
- Department of Anaesthesiology, Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Yuanhai Li
- Department of Anaesthesiology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
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The Effect of Exercise and Folate Nano-Liposomes on D1 and D2 Receptor Gene Expression in the Brain of Alzheimer's Rats. JORJANI BIOMEDICINE JOURNAL 2022. [DOI: 10.52547/jorjanibiomedj.10.2.36] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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Wang P, Li CG, Zhou X, Ding S. Transcription factor EB enhances autophagy and ameliorates palmitate-induced insulin resistance at least partly via upregulating AMPK activity in skeletal muscle cells. Clin Exp Pharmacol Physiol 2021; 49:302-310. [PMID: 34614219 DOI: 10.1111/1440-1681.13600] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 10/01/2021] [Accepted: 10/01/2021] [Indexed: 12/22/2022]
Abstract
This study aimed to elucidate the role of transcription factor EB (TFEB) in protecting C2C12 myotubes against palmitate (PA)-induced insulin resistance (IR) and explored its mechanism associated with autophagy. PA treatment significantly decreased insulin sensitivity in myotubes and downregulated TFEB protein expression. TFEB overexpression significantly reversed the PA-suppressed glucose transporter 4 (GLUT4) protein expression and improved intracellular glucose uptake and consumption, and also alleviated the decrease of autophagy markers induced by PA. The effect of TFEB overexpression on GLUT4 was also abolished by the autophagy inhibitor 3-MA. In addition, AMPKɑ2-DN inhibited or abolished the effects of TFEB overexpression on upregulation of GLUT4 and PA-induced decrease of autophagy marker expressions. Taken together, our data demonstrated that upregulation of TFEB improved PA-induced IR in C2C12 myotubes by enhancing autophagy and upregulating AMPK activity. TFEB, as a critical regulator of glucose homeostasis in skeletal muscle cells, may be a potential therapeutic target for IR and Type 2 diabetes.
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Affiliation(s)
- Ping Wang
- School of Physical Education, Hangzhou Normal University, Hangzhou, China
| | - Chun Guang Li
- NICM Health Research Institute, Western Sydney University, Westmead, New South Wales, Australia
| | - Xian Zhou
- NICM Health Research Institute, Western Sydney University, Westmead, New South Wales, Australia
| | - Shuzhe Ding
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention, Ministry of Education, East China Normal University, Shanghai, China.,School of Physical Education & Health, East China Normal University, Shanghai, China
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Youssef AM, Mohamed DA, Hussein S, Abdullah DM, Abdelrahman SA. Effects of Quercetin and Coenzyme Q10 on Biochemical, Molecular, and Morphological Parameters of Skeletal Muscle in Trained Diabetic Rats. Curr Mol Pharmacol 2021; 15:239-251. [PMID: 34061009 DOI: 10.2174/1874467214666210521170339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 01/28/2021] [Accepted: 01/29/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND Diabetes mellitus (DM) affects the musculoskeletal system through its metabolic perturbations. Exercise modulates blood sugar levels and increases the body's sensitivity to insulin in patients with DM. OBJECTIVE This study aimed to investigate the potential effects of combined quercetin and coenzyme Q10 (CoQ10) supplements with or without exercise on the histological, biochemical and molecular structures of diabetic rat's skeletal muscle. METHOD A total of 64 adult male albino rats were divided into six groups: control, trained nondiabetic, non-trained diabetic, diabetic rats treated with combined CoQ10 and quercetin, diabetic rats with treadmill training, and diabetic rats treated with treadmill training and CoQ10 and quercetin. Blood and skeletal muscle samples were obtained from all groups for routine histological examination and biochemical determination of cytokine levels and protein activities. Quantitative real-time polymerase chain reaction (qRT-PCR) and morphometric analysis of PAS and Bax expressions were also performed. RESULTS Biochemical analysis revealed improvement in all studied parameters with combined CoQ10 and quercetin than exercise training alone. Combined treatment and exercise showed significant improvement in all parameters especially interleukin 6 and malondialdehyde. Fibronectin type III domain-containing protein 5 (FNDC5) expression and irisin levels increased in all trained groups but combined treatment with exercise significantly increased their levels than exercise alone. Histological analysis revealed improvement after exercise or combined treatment; however, when exercise was combined with CoQ10 and quercetin, marked improvement was observed. CONCLUSION the combination of CoQ10 and quercetin could be promising in preserving musculoskeletal function in patients with DM concomitantly with physical exercise.
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Affiliation(s)
- Amal M Youssef
- Department of Physiology, Faculty of Medicine, Taibah University, Medinah, Saudi Arabia
| | - Dalia A Mohamed
- Medical Histology and Cell Biology Department, Faculty of Medicine, Zagazig University, Zagazig, Egypt
| | - Samia Hussein
- Medical Biochemistry and Molecular Biology Department, Faculty of Medicine, Zagazig University, Zagazig, Egypt
| | - Doaa M Abdullah
- Pharmacology Department, Faculty of Medicine, Zagazig University, Zagazig, Egypt
| | - Shaimaa A Abdelrahman
- Medical Histology and Cell Biology Department, Faculty of Medicine, Zagazig University, Zagazig, Egypt
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Pileggi CA, Parmar G, Harper ME. The lifecycle of skeletal muscle mitochondria in obesity. Obes Rev 2021; 22:e13164. [PMID: 33442950 DOI: 10.1111/obr.13164] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/10/2020] [Accepted: 10/12/2020] [Indexed: 12/12/2022]
Abstract
Skeletal muscle possesses dramatic metabolic plasticity that allows for the rapid adaptation in cellular energy transduction to meet the demands of the organism. Obesity elicits changes in skeletal muscle structure and function, resulting in the accumulation of intramuscular lipids. The accumulation of intramuscular lipids in obesity is associated with impaired skeletal muscle mitochondrial content and function. Mitochondria exist as a dynamic network that is regulated by the processes of biogenesis, fusion, fission, and mitophagy. In this review, we outline adaptations in molecular pathways that regulate mitochondrial structure and function in obesity. We highlight the emerging role of dysregulated skeletal muscle macroautophagy and mitochondrial turnover in obesity. Future research should further elucidate the role of mitophagy in observed reductions in mitochondrial content and function during obesity.
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Affiliation(s)
- Chantal A Pileggi
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada.,Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - Gaganvir Parmar
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada.,Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - Mary-Ellen Harper
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada.,Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
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Huang Y, Liu HT, Yuan Y, Guo YP, Wan DF, Pan SS. Exercise Preconditioning Increases Beclin1 and Induces Autophagy to Promote Early Myocardial Protection via Intermittent Myocardial Ischemia-Hypoxia. Int Heart J 2021; 62:407-415. [PMID: 33678798 DOI: 10.1536/ihj.20-597] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Exercise preconditioning (EP) provides protective effects for acute cardiovascular stress; however, its mechanisms need to be further investigated. Autophagy is a degradation pathway essential for myocardium health. Therefore, we investigated whether intermittent myocardial ischemia-hypoxia affected Beclin1 and whether the changes in autophagy levels contribute to EP-induced early myocardial protective effects. Rats were trained on a treadmill using an EP model (four cycles of 10 minutes of running/10 minutes of rest). Exhaustive exercise (EE) was performed to induce myocardial injury. Cardiac troponin I (cTnI) and ischemia-hypoxia staining were used to evaluate myocardial injury and protection. Double-labeled immunofluorescence staining and western blot analysis were employed to examine related markers. EP attenuated the myocardial ischemic-hypoxic injury induced by EE. Compared with the control (C) group, the dissociations of Beclin1/Bcl-2 ratio and Beclin1 expression were both higher in all other groups. Compared with the C group, PI3KC3 and the LC3-II/LC3-I ratio were higher in all other groups, whereas LC3-II was higher in the EE and EEP + EE groups. p62 was higher in the EE group than in the C group but lower in the EEP + EE group than in the EE group. We concluded that EP increases Beclin1 via intermittent myocardial ischemia-hypoxia and induces autophagy, which exerts early myocardial protective effects and reduces the myocardial ischemic-hypoxic injury induced by exhaustive exercise.
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Affiliation(s)
- Yue Huang
- School of Kinesiology, Shanghai University of Sport
| | - Hong-Tao Liu
- School of Kinesiology, Shanghai University of Sport
| | - Yang Yuan
- School of Kinesiology, Shanghai University of Sport
| | - Yuan-Pan Guo
- School of Kinesiology, Shanghai University of Sport
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10
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Kwon I, Song W, Jang Y, Choi MD, Vinci DM, Lee Y. Elevation of hepatic autophagy and antioxidative capacity by endurance exercise is associated with suppression of apoptosis in mice. Ann Hepatol 2021; 19:69-78. [PMID: 31611063 DOI: 10.1016/j.aohep.2019.08.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 08/16/2019] [Accepted: 08/18/2019] [Indexed: 02/04/2023]
Abstract
INTRODUCTION AND OBJECTIVES Endurance exercise (EXE) has emerged as a potent inducer of autophagy essential in maintaining cellular homeostasis in various tissues; however, the functional significance and molecular mechanisms of EXE-induced autophagy in the liver remain unclear. Thus, the aim of this study is to examine the signaling nexus of hepatic autophagy pathways occurring during acute EXE and a potential crosstalk between autophagy and apoptosis. MATERIALS AND METHODS C57BL/6 male mice were randomly assigned to sedentary control group (CON, n=9) and endurance exercise (EXE, n=9). Mice assigned to EXE were gradually acclimated to treadmill running and ran for 60min per day for five consecutive days. RESULTS Our data showed that EXE promoted hepatic autophagy via activation of canonical autophagy signaling pathways via mediating microtubule-associated protein B-light chain 3 II (LC3-II), autophagy protein 7 (ATG7), phosphorylated adenosine mono phosphate-activated protein kinase (p-AMPK), CATHEPSIN L, lysosome-associated membrane protein 2 (LAMP2), and a reduction in p62. Interestingly, this autophagy promotion concurred with enhanced anabolic activation via AKT-mammalian target of rapamycin (mTOR)-p70S6K signaling cascade and enhanced antioxidant capacity such as copper zinc superoxide dismutase (CuZnSOD), glutathione peroxidase (GPX), and peroxiredoxin 3 (PRX3), known to be as antagonists of autophagy. Moreover, exercise-induced autophagy was inversely related to apoptosis in the liver. CONCLUSIONS Our findings indicate that improved autophagy and antioxidant capacity, and potentiated anabolic signaling may be a potent non-pharmacological therapeutic strategy against diverse liver diseases.
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Affiliation(s)
- Insu Kwon
- Molecular and Cellular Exercise Physiology Laboratory, Department of Movement Sciences and Health, Usha Kundu, MD College of Health, University of West Florida, Pensacola, FLUSA
| | - Wankeun Song
- Molecular and Cellular Exercise Physiology Laboratory, Department of Movement Sciences and Health, Usha Kundu, MD College of Health, University of West Florida, Pensacola, FLUSA
| | - Yongchul Jang
- Molecular and Cellular Exercise Physiology Laboratory, Department of Movement Sciences and Health, Usha Kundu, MD College of Health, University of West Florida, Pensacola, FLUSA
| | - Myung D Choi
- Exercise Science, School of Health Sciences, Oakland University, Rochester, MIUSA
| | - Debra M Vinci
- Molecular and Cellular Exercise Physiology Laboratory, Department of Movement Sciences and Health, Usha Kundu, MD College of Health, University of West Florida, Pensacola, FLUSA
| | - Youngil Lee
- Molecular and Cellular Exercise Physiology Laboratory, Department of Movement Sciences and Health, Usha Kundu, MD College of Health, University of West Florida, Pensacola, FLUSA.
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Skuratovskaia D, Komar A, Vulf M, Litvinova L. Mitochondrial destiny in type 2 diabetes: the effects of oxidative stress on the dynamics and biogenesis of mitochondria. PeerJ 2020; 8:e9741. [PMID: 32904391 PMCID: PMC7453922 DOI: 10.7717/peerj.9741] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 07/26/2020] [Indexed: 12/28/2022] Open
Abstract
Background One reason for the development of insulin resistance is the chronic inflammation in obesity. Materials & Methods Scientific articles in the field of knowledge on the involvement of mitochondria and mitochondrial DNA (mtDNA) in obesity and type 2 diabetes were analyzed. Results Oxidative stress developed during obesity contributes to the formation of peroxynitrite, which causes cytochrome C-related damage in the mitochondrial electron transfer chain and increases the production of reactive oxygen species (ROS), which is associated with the development of type 2 diabetes. Oxidative stress contributes to the nuclease activity of the mitochondrial matrix, which leads to the accumulation of cleaved fragments and an increase in heteroplasmy. Mitochondrial dysfunction and mtDNA variations during insulin resistance may be connected with a change in ATP levels, generation of ROS, mitochondrial division/fusion and mitophagy. This review discusses the main role of mitochondria in the development of insulin resistance, which leads to pathological processes in insulin-dependent tissues, and considers potential therapeutic directions based on the modulation of mitochondrial biogenesis. In this regard, the development of drugs aimed at the regulation of these processes is gaining attention. Conclusion Changes in the mtDNA copy number can help to protect mitochondria from severe damage during conditions of increased oxidative stress. Mitochondrial proteome studies are conducted to search for potential therapeutic targets. The use of mitochondrial peptides encoded by mtDNA also represents a promising new approach to therapy.
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Affiliation(s)
| | - Alexandra Komar
- Immanuel Kant Baltic Federal University, Kaliningrad, Russian Federation
| | - Maria Vulf
- Immanuel Kant Baltic Federal University, Kaliningrad, Russian Federation
| | - Larisa Litvinova
- Immanuel Kant Baltic Federal University, Kaliningrad, Russian Federation
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Herrenbruck AR, Bollinger LM. Role of skeletal muscle autophagy in high-fat-diet-induced obesity and exercise. Nutr Rev 2020; 78:56-64. [PMID: 31529063 DOI: 10.1093/nutrit/nuz044] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Autophagy is a complex degradation pathway responsible for clearing damaged and dysfunctional organelles. High-fat-diet-induced obesity has been shown to alter autophagy throughout the body in a tissue-specific manner. The impact of obesity on skeletal muscle autophagy has yet to be elucidated. This review examines the impact of high-fat-diet-induced obesity and exercise on skeletal muscle autophagy. Better understanding this major quality control mechanism may help develop novel therapies to combat high-fat-diet-induced obesity comorbidities.
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Affiliation(s)
- Adrienne R Herrenbruck
- A.R. Herrenbruck, and L.M. Bollinger are with the Department of Kinesiology and Health Promotion, University of Kentucky, Lexington, Kentucky, USA
| | - Lance M Bollinger
- A.R. Herrenbruck, and L.M. Bollinger are with the Department of Kinesiology and Health Promotion, University of Kentucky, Lexington, Kentucky, USA
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Type 2 diabetes-induced overactivation of P300 contributes to skeletal muscle atrophy by inhibiting autophagic flux. Life Sci 2020; 258:118243. [PMID: 32791154 DOI: 10.1016/j.lfs.2020.118243] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 07/24/2020] [Accepted: 08/06/2020] [Indexed: 12/25/2022]
Abstract
AIMS Although autophagy impairment is a well-established cause of muscle atrophy and P300 has recently been identified as an important regulator of autophagy, the effects of P300 on autophagy and muscle atrophy in type 2 diabetes (T2D) remain unexplored. We aimed at characterizing the role of P300 in diabetic muscle and its underlying mechanism. MAIN METHODS Protein levels of phosphorylated P300, total P300, acetylated histone H3, LC3, p62 and myosin heavy chain, and mRNA levels of Atrogin-1 and MuRF1 were analyzed in palmitic acid (PA)-treated myotubes and db/db mice. Autophagic flux was assessed using transmission electron microscopy, immunofluorescence and mRFP-GFP-LC3 lentivirus transfection in cells. Muscle weight, blood glucose and grip strength were measured in mice. Hematoxylin and eosin (H&E) staining was performed to determine changes in muscle fiber size. To investigate the effects of P300 on autophagy and myofiber remodeling, a P300 specific inhibitor, c646, was utilized. 3-Methyladenine (3-MA) was utilized to inhibit autophagosomes formation, and chloroquine (CQ) was used to block autophagic flux. KEY FINDINGS Phosphorylation of P300 in response to PA enhanced its activity and subsequently suppressed autophagic flux, leading to atrophy-related morphological and molecular changes in myotubes. Inhibition of P300 reestablished autophagic flux and ameliorated PA-induced myotubes atrophy. However, this effect was largely abolished by co-treatment with the autophagy inhibitor CQ. In vivo results demonstrated that inhibition of P300 partially rescued muscle wasting in db/db mice, accompanied with autophagy reactivation. SIGNIFICANCE The findings revealed that T2D-induced overactivation of P300 contributes to muscle atrophy by blocking autophagic flux.
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Wang Y, Zhang K, Qi X, Yang G, Wang H, Zhang Z, Yang B. Effects of propofol on LC3II and mTOR/p-mTOR expression during ischemia-reperfusion myocardium injury in rats with type 2 diabetes mellitus. Exp Ther Med 2020; 19:2441-2448. [PMID: 32256720 PMCID: PMC7098214 DOI: 10.3892/etm.2020.8499] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 11/05/2019] [Indexed: 01/11/2023] Open
Abstract
To investigate the effects of propofol on myocardial ischemia reperfusion in rats with type 2 diabetes, male adult rats were divided into five groups: Sham-operation (CC), ischemia-reperfusion (CI), low-dose propofol (LP), moderate-dose propofol (MP) and high-dose propofol (HP). The LP, MP and HP groups were administered with 6, 12 and 24 mg/kg/h propofol, respectively, prior to occlusion. Heart rate (HR), left ventricular systolic pressure (LVSP) and the rate (dp/dt max) of left ventricular pressure rise in early systole (±dp/dt max) were recorded. The role of autophagy was also studied by measuring the levels of superoxide dismutase (SOD), malondialdehyde (MDA), autophagy marker protein LC3II, mammalian target of rapamycin (mTOR)/phosphorylate (p)-mTOR and cardiac troponin T (cTnT). The myocardial morphological features were assessed using light and electron microscopy. The present results demonstrated that the HR, LVSP, +dp/dt and -dp/dt levels in the propofol groups (LP, MP and HP) were significantly increased (P<0.05) when compared with the CI group. The myocardial cells in the MP group showed mild edematous changes and partially dissolved mitochondrial cristae and membrane rupture. SOD, cTnT and MDA levels were significantly decreased (P<0.05), mTOR expression decreased significantly (P<0.05) and p-mTOR expression increased significantly in the MP group (P<0.05). The present study demonstrated the protective effects of propofol in T2DM rats exhibiting MIRI, with an optimal protective effect at an infusion rate of 12 mg/kg/h. Additionally, the results revealed that propofol led to significant reductions in LC3II and mTOR serum levels and the inhibition of autophagy in myocardial cells.
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Affiliation(s)
- Ying Wang
- Department of Anesthesiology, Affiliated Hospital of Hebei University, Baoding, Hebei 071000, P.R. China
| | - Kecheng Zhang
- Department of Medicine, Hebei University, Baoding, Hebei 071000, P.R. China
| | - Xiuru Qi
- Department of Medicine, Hebei University, Baoding, Hebei 071000, P.R. China
| | - Guang Yang
- Department of Anesthesiology, Affiliated Hospital of Hebei University, Baoding, Hebei 071000, P.R. China
| | - Hongjie Wang
- Department of Medicine, Hebei University, Baoding, Hebei 071000, P.R. China
| | - Zhe Zhang
- Hebei Medical Science and Technology Development Research Center, Shijiazhuang, Hebei 051000, P.R. China
| | - Baofeng Yang
- Health and Family Planning Commission of Hebei, Shijiazhuang, Hebei 050000, P.R. China
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Rosa-Caldwell ME, Jansen LT, Lim S, Dunlap KR, Haynie WS, Washington TA, Greene NP. Neither autophagy nor exercise training mode affect exercise-induced beneficial adaptations in high fat-fed mice. SPORTS MEDICINE AND HEALTH SCIENCE 2020; 2:44-53. [PMID: 35783331 PMCID: PMC9219353 DOI: 10.1016/j.smhs.2020.03.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 02/28/2020] [Accepted: 03/04/2020] [Indexed: 01/06/2023] Open
Abstract
Purpose Methods Results Conclusions
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16
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Fan Z, Xiao Q. Impaired autophagic flux contributes to muscle atrophy in obesity by affecting muscle degradation and regeneration. Biochem Biophys Res Commun 2020; 525:462-468. [PMID: 32102751 DOI: 10.1016/j.bbrc.2020.02.110] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Accepted: 02/15/2020] [Indexed: 12/23/2022]
Abstract
Increased proteolytic activity has been widely associated with skeletal muscle atrophy. However, elevated proteolysis is also critical for the maintenance of intracellular homeostasis. In this study, we aimed to investigate the significance of autophagy in obesity-induced muscle atrophy and clarify the mechanism involved. First, high-fat diet (HFD)-fed rats were administered vehicle or chloroquine (CQ), an autophagy inhibitor, and we found that HFD inhibited autophagic flux and reduced myofiber size and function in rats. Additionally, the expression levels of MyoD were decreased whereas those of Atrogin-1 were increased in rats fed a HFD. Sustained autophagy inhibition by CQ exacerbated HFD-induced muscular damage and changes in the expression of Atrogin-1 and MyoD. Similar effects were reproduced in vitro in myotubes, which exhibited increased levels of autophagy-related proteins, but the resultant autophagic flux was reduced following exposure to palmitic acid (PA)-conditioned medium. Moreover, PA significantly decreased MyoD levels and induced Atrogin-1 expression, leading to progressive myotube atrophy; this phenomenon was aggravated by CQ but alleviated by the autophagy activator rapamycin. Taken together, these in vivo and in vitro findings suggest that autophagic flux is blocked in skeletal muscle of individuals with high lipid, and autophagy mediates high lipid-induced muscle atrophy by affecting muscle degradation and regeneration.
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Affiliation(s)
- Zhen Fan
- Department of Geriatrics, First Affiliated Hospital of Chongqing Medical University, Friendship Road 1, Yuan Jiagang, 400016, Chongqing, China.
| | - Qian Xiao
- Department of Geriatrics, First Affiliated Hospital of Chongqing Medical University, Friendship Road 1, Yuan Jiagang, 400016, Chongqing, China.
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Chang H, Peng X, Yan X, Zhang J, Xu S, Wang H, Wang Z, Ma X, Gao Y. Autophagy and Akt-mTOR signaling display periodic oscillations during torpor-arousal cycles in oxidative skeletal muscle of Daurian ground squirrels (Spermophilus dauricus). J Comp Physiol B 2019; 190:113-123. [PMID: 31729534 DOI: 10.1007/s00360-019-01245-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 10/20/2019] [Accepted: 11/06/2019] [Indexed: 12/29/2022]
Abstract
Whether hibernation accelerates or suppresses autophagy is still unknown. In the current study, we examined changes in autophagy in oxidative soleus (SOL) muscle in summer active (SA), pre-hibernation (PRE), torpor (TOR), interbout arousal (IBA), and post-hibernation groups of Daurian ground squirrels (Spermophilus dauricus). Here, the SOL muscle showed no significant atrophy during hibernation in regard to muscle wet weight, fiber cross-sectional area, or MuRF1 protein level. Autophagy-related proteins beclin1 and Atg7 increased significantly, whereas LC3-II decreased significantly in the PRE group compared with the SA group. However, neither the expression nor activity of cathepsin L showed any differences between the SA and PRE groups. In addition, beclin1, LC3-II, and the LC3-II/LC3-I ratio increased, p62 decreased, LC3 puncta increased, p62 puncta decreased, and cathepsin L activity increased in the TOR group compared with the PRE group. In contrast, beclin1, LC3-II, and the LC3-II/LC3-I ratio decreased, p62 increased, LC3 puncta decreased, p62 puncta increased, and cathepsin L activity declined in the IBA group compared with the TOR group. Moreover, the phosphorylation of Akt (Ser473) and mTOR (Ser2448) changed significantly during hibernation and showed an inverse relationship with autophagy changes. In conclusion, autophagy proteins displayed periodic oscillation in the torpor-arousal cycle, which may be advantageous in maintaining SOL muscle mass during the entire hibernation period. Furthermore, the Akt-mTOR signaling was decreased in TOR and increased in IBA group in the SOL muscle of Daurian ground squirrels during hibernation.
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Affiliation(s)
- Hui Chang
- Shaanxi Key Laboratory for Animal Conservation, Northwest University, Xi'an, 710069, People's Republic of China.,Key Laboratory of Resource Biology and Biotechnology in Western China, College of Life Sciences, Northwest University, Ministry of Education, 229# North Taibai Road, Xi'an, 710069, People's Republic of China
| | - Xin Peng
- Key Laboratory of Resource Biology and Biotechnology in Western China, College of Life Sciences, Northwest University, Ministry of Education, 229# North Taibai Road, Xi'an, 710069, People's Republic of China
| | - Xia Yan
- Key Laboratory of Resource Biology and Biotechnology in Western China, College of Life Sciences, Northwest University, Ministry of Education, 229# North Taibai Road, Xi'an, 710069, People's Republic of China
| | - Jie Zhang
- Key Laboratory of Resource Biology and Biotechnology in Western China, College of Life Sciences, Northwest University, Ministry of Education, 229# North Taibai Road, Xi'an, 710069, People's Republic of China
| | - Shenhui Xu
- Key Laboratory of Resource Biology and Biotechnology in Western China, College of Life Sciences, Northwest University, Ministry of Education, 229# North Taibai Road, Xi'an, 710069, People's Republic of China
| | - Huiping Wang
- Shaanxi Key Laboratory for Animal Conservation, Northwest University, Xi'an, 710069, People's Republic of China.,Key Laboratory of Resource Biology and Biotechnology in Western China, College of Life Sciences, Northwest University, Ministry of Education, 229# North Taibai Road, Xi'an, 710069, People's Republic of China
| | - Zhe Wang
- Key Laboratory of Resource Biology and Biotechnology in Western China, College of Life Sciences, Northwest University, Ministry of Education, 229# North Taibai Road, Xi'an, 710069, People's Republic of China
| | - Xiufeng Ma
- Key Laboratory of Resource Biology and Biotechnology in Western China, College of Life Sciences, Northwest University, Ministry of Education, 229# North Taibai Road, Xi'an, 710069, People's Republic of China
| | - Yunfang Gao
- Shaanxi Key Laboratory for Animal Conservation, Northwest University, Xi'an, 710069, People's Republic of China. .,Key Laboratory of Resource Biology and Biotechnology in Western China, College of Life Sciences, Northwest University, Ministry of Education, 229# North Taibai Road, Xi'an, 710069, People's Republic of China.
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Chen X, Li H, Wang K, Liang X, Wang W, Hu X, Huang Z, Wang Y. Aerobic Exercise Ameliorates Myocardial Inflammation, Fibrosis and Apoptosis in High-Fat-Diet Rats by Inhibiting P2X7 Purinergic Receptors. Front Physiol 2019; 10:1286. [PMID: 31681001 PMCID: PMC6798156 DOI: 10.3389/fphys.2019.01286] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 09/25/2019] [Indexed: 01/21/2023] Open
Abstract
Background High-fat-diet (HFD) is associated with chronic low-grade inflammation. P2X7 purinergic receptors (P2X7R) are key regulators of inflammasome activation. The benefits of exercise are partly attributed to its anti-inflammatory effect, but whether it regulates P2X7R expression to improve remodeling in cardiac myocytes treated by HFD is not completely clarified. Methods Three groups of Sprague-Dawley (SD) rats were studied: (1) control group (fed a normal chow diet), (2) HFD group, and (3) HFD+ exercise group. H9c2 myocytes were pretreated with or without A438079 (a P2X7R inhibitor) and then exposed to 200 μM palmitic acid (PA) for 24 h. The levels of mRNA and protein were measured by real-time PCR and Western blot, respectively. Masson staining and hematoxylin-eosin (HE) staining were used to identify remodeling of the heart. The concentration of IL-1β in serum or supernatants were measured by ELISA. Results In vivo, collagen deposition and the number of disordered cells significantly increased in the hearts of the HFD group compared to the control group. However, exercise markedly reversed these changes in the myocardium, and the same trends were observed in the expression of MMP9, collagen I and TGF-β. Notably, the expression of P2X7R, NLRP3, caspase-1 in the hearts, and serum IL-1β level were also greatly upregulated in the heart of the HFD diet rats, and all these changes were ameliorated in the HFD + EX group. As expected, exercise also reduced the number of TUNEL-positive cells, which was consistent with the caspase-3, Bax, and Bcl-2 results. Moreover, exercise reduced body weight and blood lipid concentrations in the HFD diet rats. In vitro, we observed that the hallmark of fibrosis, inflammation and apoptosis in H9c2 myocytes enhanced by PA, and the P2X7R inhibitor treatment significantly reduced the expression of the NLRP3, caspase-1, suppressed the secretion of IL-1β of H9c2 cells, inhibited collagen I, TGF-β, MMP9, Bax, caspase-3 levels and increased the expression of Bcl-2, compared with the PA group. In addition, a decrease of the number of TUNEL-positive cells used by A438079 further support that cardiomyocytes apoptosis could be inhibited. Conclusion Aerobic exercise reversed the cardiac remodeling via the reduction of inflammation, fibrosis and apoptosis in HFD rats, at least in part through inhibiting P2X7R expression in cardiomyocytes.
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Affiliation(s)
- Xudong Chen
- The Key Lab of Cardiovascular Disease of Wenzhou, Department of Cardiology, Wenzhou Medical University, Wenzhou, China.,Department of Cardiology, Ningbo Hangzhou Bay Hospital, Ningbo, China
| | - Haiyan Li
- Department of Rehabilitation, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Kangwei Wang
- The Key Lab of Cardiovascular Disease of Wenzhou, Department of Cardiology, Wenzhou Medical University, Wenzhou, China
| | - Xiaohe Liang
- The Key Lab of Cardiovascular Disease of Wenzhou, Department of Cardiology, Wenzhou Medical University, Wenzhou, China
| | - Weiqi Wang
- The Key Lab of Cardiovascular Disease of Wenzhou, Department of Cardiology, Wenzhou Medical University, Wenzhou, China
| | - Xiaokang Hu
- The Key Lab of Cardiovascular Disease of Wenzhou, Department of Cardiology, Wenzhou Medical University, Wenzhou, China
| | - Zhouqing Huang
- Department of Cardiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Yonghua Wang
- Department of Physical Education, Wenzhou Medical University, Wenzhou, China
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Ato S, Kido K, Sato K, Fujita S. Type 2 diabetes causes skeletal muscle atrophy but does not impair resistance training-mediated myonuclear accretion and muscle mass gain in rats. Exp Physiol 2019; 104:1518-1531. [PMID: 31328833 PMCID: PMC6790689 DOI: 10.1113/ep087585] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Accepted: 07/19/2019] [Indexed: 12/12/2022]
Abstract
New Findings What is the central question of this study? Type 2 diabetes mellitus (T2DM) causes skeletal muscle atrophy; does it affect resistance training (RT)‐mediated molecular adaptations and subsequent muscle hypertrophy? What is the main finding and its importance? Although skeletal muscle mass and regulation were not preserved under conditions of T2DM, the response of RT‐induced skeletal muscle hypertrophy was not impaired in T2DM rat skeletal muscle. These findings suggest that the capacity of RT‐mediated muscle mass gain is not diminished in the T2DM condition.
Abstract Type 2 diabetes mellitus (T2DM) is known to cause skeletal muscle atrophy. However, it is not known whether T2DM affects resistance training (RT)‐mediated molecular adaptations and subsequent muscle hypertrophy. Therefore, we investigated the effect of T2DM on response of skeletal muscle hypertrophy to chronic RT using a rat resistance exercise mimetic model. T2DM and healthy control rats were subjected to 18 bouts (3 times per week) of chronic RT on unilateral lower legs. RT significantly increased gastrocnemius muscle mass and myonuclei in both T2DM and healthy control rats to the same extent, even though T2DM caused muscle atrophy in the resting condition. Further, T2DM significantly reduced mechanistic target of rapamycin complex 1 (mTORC1) activity (phosphorylation of p70S6KThr389 and 4E‐BP1Thr37/46) to insulin stimulation and the number of myonuclei in the untrained basal condition, but RT‐mediated adaptations were not affected by T2DM. These findings suggested that although the skeletal muscle mass and regulation were not preserved under basal conditions of T2DM, the response of RT‐induced skeletal muscle hypertrophy was not impaired in T2DM rat skeletal muscle.
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Affiliation(s)
- Satoru Ato
- Graduate School of Sport and Health Science, Ritsumeikan University, Kusatsu, Japan
| | - Kohei Kido
- Graduate School of Sport and Health Science, Ritsumeikan University, Kusatsu, Japan
| | - Koji Sato
- Faculty of Human Development, Kobe University, Kobe, Japan
| | - Satoshi Fujita
- Graduate School of Sport and Health Science, Ritsumeikan University, Kusatsu, Japan
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Effect of Bangle (Zingiber purpureum) extract and low-intensity exercise on mTOR phosphorylation and autophagy flux in skeletal muscles of rats on a high-fat diet. J Funct Foods 2018. [DOI: 10.1016/j.jff.2018.06.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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