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Iseki Y, Ono Y, Hibi C, Tanaka S, Takeshita S, Maejima Y, Kurokawa J, Murakawa M, Shimomura K, Sakamoto K. Opening of Intermediate Conductance Ca 2+-Activated K + Channels in C2C12 Skeletal Muscle Cells Increases the Myotube Diameter via the Akt/Mammalian Target of Rapamycin Pathway. J Pharmacol Exp Ther 2020; 376:454-462. [PMID: 33376149 DOI: 10.1124/jpet.120.000290] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 12/23/2020] [Indexed: 11/22/2022] Open
Abstract
The activation of potassium channels and the ensuing hyperpolarization in skeletal myoblasts are essential for myogenic differentiation. However, the effects of K+ channel opening in myoblasts on skeletal muscle mass are unclear. Our previous study revealed that pharmacological activation of intermediate conductance Ca2+-activated K+ channels (IKCa channels) increases myotube formation. In this study, we investigated the effects of 5,6-dichloro-1-ethyl-1,3-dihydro-2H-benzimidazol-2-one (DCEBIO), a Ca2+-activated K+ channel opener, on the mass of skeletal muscle. Application of DCEBIO to C2C12 cells during myogenesis increased the diameter of C2C12 myotubes in a concentration-dependent manner. This DCEBIO-induced hypertrophy was abolished by gene silencing of IKCa channels. However, it was resistant to 1 µM but sensitive to 10 µM TRAM-34, a specific IKCa channel blocker. Furthermore, DCEBIO reduced the mitochondrial membrane potential by opening IKCa channels. Therefore, DCEBIO should increase myotube mass by opening of IKCa channels distributed in mitochondria. Pharmacological studies revealed that mitochondrial reactive oxygen species (mitoROS), Akt, and mammalian target of rapamycin (mTOR) are involved in DCEBIO-induced myotube hypertrophy. An additional study demonstrated that DCEBIO-induced muscle hypertrophic effects are only observed when applied in the early stage of myogenic differentiation. In an in vitro myotube inflammatory atrophy experiment, DCEBIO attenuated the reduction of myotube diameter induced by endotoxin. Thus, we concluded that DCEBIO increases muscle mass by activating the IKCa channel/mitoROS/Akt/mTOR pathway. Our study suggests the potential of DCEBIO in the treatment of muscle wasting diseases. SIGNIFICANCE STATEMENT: Our study shows that 5,6-dichloro-1-ethyl-1,3-dihydro-2H-benzimidazol-2-one (DCEBIO), a small molecule opener of Ca2+-activated K+ channel, increased muscle diameter via the mitochondrial reactive oxygen species/Akt/mammalian target of rapamycin pathway. And DCEBIO overwhelms C2C12 myotube atrophy induced by endotoxin challenge. Our report should inform novel role of K+ channel in muscle development and novel usage of K+ channel opener such as for the treatment of muscle wasting diseases.
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Affiliation(s)
- Yuzo Iseki
- Departments of Bioregulation and Pharmacological Medicine (Y.I., Y.O., S.T., Y.M., K.Sh., K.Sa.) and Anesthesiology (Y.I., M.M.), Fukushima Medical University, School of Medicine, Fukushima, Japan; Department of Disaster and Emergency Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan (Y.O.); and Department of Bio-Informational Pharmacology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka-shi, Shizuoka, Japan (C.H., S.T., J.K., K.Sa.)
| | - Yuko Ono
- Departments of Bioregulation and Pharmacological Medicine (Y.I., Y.O., S.T., Y.M., K.Sh., K.Sa.) and Anesthesiology (Y.I., M.M.), Fukushima Medical University, School of Medicine, Fukushima, Japan; Department of Disaster and Emergency Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan (Y.O.); and Department of Bio-Informational Pharmacology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka-shi, Shizuoka, Japan (C.H., S.T., J.K., K.Sa.)
| | - Chihiro Hibi
- Departments of Bioregulation and Pharmacological Medicine (Y.I., Y.O., S.T., Y.M., K.Sh., K.Sa.) and Anesthesiology (Y.I., M.M.), Fukushima Medical University, School of Medicine, Fukushima, Japan; Department of Disaster and Emergency Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan (Y.O.); and Department of Bio-Informational Pharmacology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka-shi, Shizuoka, Japan (C.H., S.T., J.K., K.Sa.)
| | - Shoko Tanaka
- Departments of Bioregulation and Pharmacological Medicine (Y.I., Y.O., S.T., Y.M., K.Sh., K.Sa.) and Anesthesiology (Y.I., M.M.), Fukushima Medical University, School of Medicine, Fukushima, Japan; Department of Disaster and Emergency Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan (Y.O.); and Department of Bio-Informational Pharmacology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka-shi, Shizuoka, Japan (C.H., S.T., J.K., K.Sa.)
| | - Shunya Takeshita
- Departments of Bioregulation and Pharmacological Medicine (Y.I., Y.O., S.T., Y.M., K.Sh., K.Sa.) and Anesthesiology (Y.I., M.M.), Fukushima Medical University, School of Medicine, Fukushima, Japan; Department of Disaster and Emergency Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan (Y.O.); and Department of Bio-Informational Pharmacology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka-shi, Shizuoka, Japan (C.H., S.T., J.K., K.Sa.)
| | - Yuko Maejima
- Departments of Bioregulation and Pharmacological Medicine (Y.I., Y.O., S.T., Y.M., K.Sh., K.Sa.) and Anesthesiology (Y.I., M.M.), Fukushima Medical University, School of Medicine, Fukushima, Japan; Department of Disaster and Emergency Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan (Y.O.); and Department of Bio-Informational Pharmacology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka-shi, Shizuoka, Japan (C.H., S.T., J.K., K.Sa.)
| | - Junko Kurokawa
- Departments of Bioregulation and Pharmacological Medicine (Y.I., Y.O., S.T., Y.M., K.Sh., K.Sa.) and Anesthesiology (Y.I., M.M.), Fukushima Medical University, School of Medicine, Fukushima, Japan; Department of Disaster and Emergency Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan (Y.O.); and Department of Bio-Informational Pharmacology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka-shi, Shizuoka, Japan (C.H., S.T., J.K., K.Sa.)
| | - Masahiro Murakawa
- Departments of Bioregulation and Pharmacological Medicine (Y.I., Y.O., S.T., Y.M., K.Sh., K.Sa.) and Anesthesiology (Y.I., M.M.), Fukushima Medical University, School of Medicine, Fukushima, Japan; Department of Disaster and Emergency Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan (Y.O.); and Department of Bio-Informational Pharmacology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka-shi, Shizuoka, Japan (C.H., S.T., J.K., K.Sa.)
| | - Kenju Shimomura
- Departments of Bioregulation and Pharmacological Medicine (Y.I., Y.O., S.T., Y.M., K.Sh., K.Sa.) and Anesthesiology (Y.I., M.M.), Fukushima Medical University, School of Medicine, Fukushima, Japan; Department of Disaster and Emergency Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan (Y.O.); and Department of Bio-Informational Pharmacology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka-shi, Shizuoka, Japan (C.H., S.T., J.K., K.Sa.)
| | - Kazuho Sakamoto
- Departments of Bioregulation and Pharmacological Medicine (Y.I., Y.O., S.T., Y.M., K.Sh., K.Sa.) and Anesthesiology (Y.I., M.M.), Fukushima Medical University, School of Medicine, Fukushima, Japan; Department of Disaster and Emergency Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan (Y.O.); and Department of Bio-Informational Pharmacology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka-shi, Shizuoka, Japan (C.H., S.T., J.K., K.Sa.)
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Xia Z, Cholewa J, Zhao Y, Shang HY, Yang YQ, Araújo Pessôa K, Su QS, Lima-Soares F, Zanchi NE. Targeting Inflammation and Downstream Protein Metabolism in Sarcopenia: A Brief Up-Dated Description of Concurrent Exercise and Leucine-Based Multimodal Intervention. Front Physiol 2017; 8:434. [PMID: 28690550 PMCID: PMC5479895 DOI: 10.3389/fphys.2017.00434] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Accepted: 06/06/2017] [Indexed: 01/31/2023] Open
Abstract
Sarcopenia is defined as the progressive loss of muscle mass with age, and poses a serious threat to the physiological and psychological health of the elderly population with consequential economic and social burdens. Chronic low-grade inflammation plays a central role in the development of sarcopenia such that it alters cellular protein metabolism to favor proteolysis over synthesis, and thereby accelerates muscular atrophy. The purpose of this review is to highlight how exercise and nutrition intervention strategies can attenuate or treat sarcopenia. Resistance exercise increases not only muscle mass but also muscle strength, while aerobic exercise is able to ameliorate the age-related metabolic disorders. Concurrent exercise training integrates the advantages of both aerobic and resistance exercise, and may exert a significant synergistic effect in the aging organism. Higher protein intakes rich in the amino acid leucine appear to restore skeletal muscle protein metabolism balance by rescuing protein synthesis in older adults. There is good reason to believe that a multimodal treatment, a combination of exercise and increased leucine consumption in the diet, can combat some of the muscle loss associated with aging. Future research is needed to consolidate these findings to humans, and to further clarify to what extent and by which mechanisms protein metabolism might be directly involved in sarcopenia pathogenesis and the multimodal treatment responses.
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Affiliation(s)
- Zhi Xia
- Exercise Physiology and Biochemistry Laboratory, College of Physical Education, Jinggangshan UniversityJi'an, China.,Department of Sports Medicine, Chengdu Sport UniversityChengdu, China
| | - Jason Cholewa
- Department of Kinesiology, Coastal Carolina UniversityConway, SC, United States
| | - Yan Zhao
- Exercise Physiology and Biochemistry Laboratory, College of Physical Education, Jinggangshan UniversityJi'an, China
| | - Hua-Yu Shang
- Department of Sports Medicine, Chengdu Sport UniversityChengdu, China
| | - Yue-Qin Yang
- Exercise Intervention and Health Promotion Hubei Province Synergy Innovation Center, Wuhan Sports UniversityWuhan, China
| | - Kassiana Araújo Pessôa
- Department of Physical Education, Federal University of MaranhãoSão Luís, Brazil.,Laboratory of Cellular and Molecular Biology of Skeletal Muscle (LABCEMME)São Luís, Brazil
| | - Quan-Sheng Su
- Department of Sports Medicine, Chengdu Sport UniversityChengdu, China
| | - Fernanda Lima-Soares
- Department of Physical Education, Federal University of MaranhãoSão Luís, Brazil.,Laboratory of Cellular and Molecular Biology of Skeletal Muscle (LABCEMME)São Luís, Brazil
| | - Nelo Eidy Zanchi
- Department of Physical Education, Federal University of MaranhãoSão Luís, Brazil.,Laboratory of Cellular and Molecular Biology of Skeletal Muscle (LABCEMME)São Luís, Brazil
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