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Han JW, Shin SK, Bae HR, Lee H, Moon SY, Seo WD, Kwon EY. Wheat seedlings extract ameliorates sarcopenia in aged mice by regulating protein synthesis and degradation with anti-inflammatory and mitochondrial biogenesis effects. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2024; 130:155747. [PMID: 38788397 DOI: 10.1016/j.phymed.2024.155747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Revised: 04/29/2024] [Accepted: 05/14/2024] [Indexed: 05/26/2024]
Abstract
BACKGROUND Chronic inflammation, which becomes more prevalent during aging, contributes to sarcopenia by reducing muscle mass and strength. PURPOSE Wheat seedlings extract (WSE) is known for its various physiological activities, including anti-inflammation and antioxidant effects. However, its efficacy against sarcopenia is not well documented. STUDY DESIGN 8-week-old and 50-week-old C57BL/6 J mice were used as young control (YC group) and aged controls (AC group), respectively. Then, aged mice were randomly divided into 5 groups (WSE100mg/kg, WSE200mg/kg, WSE400mg/kg, and schizandrin as a positive control) and fed each experimental diet for 10 weeks. METHOD We investigated the effects of WSE on muscle quality and protein homeostasis pathways based on improvements in mitochondrial function and chronic inflammation. We then used TNFα-treated C2C12 to investigate the effects of isoorientin (ISO) and isoschaftoside (ISS), the active substances of WSE, on the myogenic pathway. RESULTS We administered WSE to aging mice and observed an increase in muscle mass, thickness, protein content, and strength in mice treated with WSE at a dose of 200 mg/kg or 400 mg/kg. Furthermore, the administration of WSE led to a reduction in inflammatory factors (TNFα, IL-1, and IL-6) and an increase in mitochondrial biogenesis (p-AMPK/SIRT3/PGC1α) in muscle. This effect was also observed in TNFα-induced muscle atrophy in C2C12 cells, and we additionally identified the upregulation of myogenic regulatory factors, including Myf5, Myf6, MyoD, and myogenin, by WSE, ISO, and ISS. CONCLUSION These findings suggest that WSE could function as a dietary anti-inflammatory factor and mitochondrial activator, potentially exerting modulatory effects on the metabolism and mechanical properties of skeletal muscles in the aging population. Furthermore, Our results demonstrate the potential value of ISO and ISS as functional food ingredients for preventing muscle atrophy.
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Affiliation(s)
- Ji-Won Han
- Department of Food Science and Nutrition, Kyungpook National University, 80, Daehak-ro, Buk-Ku, Daegu 41566, South Korea; Center for Food and Nutritional Genomics Research, Kyungpook National University, 80, Daehak-ro, Buk-Ku, Daegu 41566, South Korea
| | - Su-Kyung Shin
- Department of Food Science and Nutrition, Kyungpook National University, 80, Daehak-ro, Buk-Ku, Daegu 41566, South Korea; Center for Food and Nutritional Genomics Research, Kyungpook National University, 80, Daehak-ro, Buk-Ku, Daegu 41566, South Korea
| | - Heekyong R Bae
- Department of Food Science and Nutrition, Kyungpook National University, 80, Daehak-ro, Buk-Ku, Daegu 41566, South Korea; Center for Food and Nutritional Genomics Research, Kyungpook National University, 80, Daehak-ro, Buk-Ku, Daegu 41566, South Korea
| | - HanGyeol Lee
- Division of Crop Foundation, National Institute of Crop Science (NICS), Rural Development Administration (RDA), Wanju 55365, South Korea
| | - So Yeon Moon
- Division of Crop Foundation, National Institute of Crop Science (NICS), Rural Development Administration (RDA), Wanju 55365, South Korea
| | - Woo Duck Seo
- Division of Crop Foundation, National Institute of Crop Science (NICS), Rural Development Administration (RDA), Wanju 55365, South Korea
| | - Eun-Young Kwon
- Center for Food and Nutritional Genomics Research, Kyungpook National University, 80, Daehak-ro, Buk-Ku, Daegu 41566, South Korea.
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Gellhaus B, Böker KO, Schilling AF, Saul D. Therapeutic Consequences of Targeting the IGF-1/PI3K/AKT/FOXO3 Axis in Sarcopenia: A Narrative Review. Cells 2023; 12:2787. [PMID: 38132107 PMCID: PMC10741475 DOI: 10.3390/cells12242787] [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: 11/06/2023] [Revised: 12/05/2023] [Accepted: 12/06/2023] [Indexed: 12/23/2023] Open
Abstract
The high prevalence of sarcopenia in an aging population has an underestimated impact on quality of life by increasing the risk of falls and subsequent hospitalization. Unfortunately, the application of the major established key therapeutic-physical activity-is challenging in the immobile and injured sarcopenic patient. Consequently, novel therapeutic directions are needed. The transcription factor Forkhead-Box-Protein O3 (FOXO3) may be an option, as it and its targets have been observed to be more highly expressed in sarcopenic muscle. In such catabolic situations, Foxo3 induces the expression of two muscle specific ubiquitin ligases (Atrogin-1 and Murf-1) via the PI3K/AKT pathway. In this review, we particularly evaluate the potential of Foxo3-targeted gene therapy. Foxo3 knockdown has been shown to lead to increased muscle cross sectional area, through both the AKT-dependent and -independent pathways and the reduced impact on the two major downstream targets Atrogin-1 and Murf-1. Moreover, a Foxo3 reduction suppresses apoptosis, activates satellite cells, and initiates their differentiation into muscle cells. While this indicates a critical role in muscle regeneration, this mechanism might exhaust the stem cell pool, limiting its clinical applicability. As systemic Foxo3 knockdown has also been associated with risks of inflammation and cancer progression, a muscle-specific approach would be necessary. In this review, we summarize the current knowledge on Foxo3 and conceptualize a specific and targeted therapy that may circumvent the drawbacks of systemic Foxo3 knockdown. This approach presumably would limit the side effects and enable an activity-independent positive impact on skeletal muscle.
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Affiliation(s)
- Benjamin Gellhaus
- Department of Trauma, Orthopedics and Reconstructive Surgery, Georg-August University of Goettingen, 37075 Goettingen, Germany; (B.G.); (K.O.B.); (A.F.S.)
| | - Kai O. Böker
- Department of Trauma, Orthopedics and Reconstructive Surgery, Georg-August University of Goettingen, 37075 Goettingen, Germany; (B.G.); (K.O.B.); (A.F.S.)
| | - Arndt F. Schilling
- Department of Trauma, Orthopedics and Reconstructive Surgery, Georg-August University of Goettingen, 37075 Goettingen, Germany; (B.G.); (K.O.B.); (A.F.S.)
| | - Dominik Saul
- Department of Trauma, Orthopedics and Reconstructive Surgery, Georg-August University of Goettingen, 37075 Goettingen, Germany; (B.G.); (K.O.B.); (A.F.S.)
- Department of Trauma and Reconstructive Surgery, Eberhard Karls University Tuebingen, BG Trauma Center Tuebingen, 72072 Tuebingen, Germany
- Division of Endocrinology, Mayo Clinic, Rochester, MN 55905, USA
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN 55905, USA
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3
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Hayes N, Fogarty M, Sadofsky L, Jones HS. Physiologically-obtainable polyphenol exposures modulate reactive oxygen and nitrogen species signaling in the C2C12 model of skeletal muscle ageing. Eur J Pharmacol 2023; 941:175511. [PMID: 36646202 DOI: 10.1016/j.ejphar.2023.175511] [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: 09/10/2022] [Revised: 01/10/2023] [Accepted: 01/13/2023] [Indexed: 01/15/2023]
Abstract
Age-related frailty is a significant health and social care burden, with limited treatment options. There is a lack of suitable cell culture model for screening large numbers of test compounds to identify those which promote healthy skeletal muscle function. This paper describes the characterization of reactive oxygen and nitrogen species (RONS) signalling changes in young and aged myoblasts and myotubes using C2C12 cells, and the application of aged cultures to assess the effect of dietary polyphenols on RONS signalling. Aged myoblasts and myotubes showed significantly increased reactive oxygen species (p < 0.01 and p < 0.001 respectively), nitric oxide (p < 0.05 for myoblasts and myotubes), and lipid peroxidation (p < 0.05 for myoblasts and myotubes). Nine polyphenols were assessed in aged myoblasts and myotubes using concentrations and incubation times consistent with known pharmacokinetic parameters for these compounds. Although several polyphenols were seen to reduce single markers of RONS signalling, only kaempferol and resveratrol significantly reduced multiple markers in both cell models. Modulation of enzymatic antioxidant activities was assessed as a possible mechanism of action, although superoxide dismutase and catalase activities were significantly reduced in aged (versus young) myotubes (p < 0.01 and p < 0.05 respectively), no effect of polyphenol treatment on these enzyme activities were observed. Overall, this research has shown the utility of the C2C12 model (myoblasts and myotubes) for screening compounds in aged muscle, and that resveratrol and kaempferol (using pharmacokinetically-informed exposures) can modulate RONS signalling in skeletal muscle cells after an acute exposure.
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Affiliation(s)
- Nathan Hayes
- Department of Biological and Marine Sciences, University of Hull, Hull, HU6 7RX, UK
| | | | - Laura Sadofsky
- Centre for Atherothrombotic and Metabolic Research, Hull York Medical School, Hull, HU6 7RX, UK
| | - Huw Simon Jones
- Institute of Cancer Therapeutics, University of Bradford, Bradford, BD7 1DP, UK.
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Hunter DJ, James LS, Hussey B, Ferguson RA, Lindley MR, Mastana SS. Impacts of Eccentric Resistance Exercise on DNA Methylation of Candidate Genes for Inflammatory Cytokines in Skeletal Muscle and Leukocytes of Healthy Males. Genes (Basel) 2023; 14:478. [PMID: 36833405 PMCID: PMC9957508 DOI: 10.3390/genes14020478] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 02/06/2023] [Accepted: 02/10/2023] [Indexed: 02/16/2023] Open
Abstract
Physical inactivity and a poor diet increase systemic inflammation, while chronic inflammation can be reduced through exercise and nutritional interventions. The mechanisms underlying the impacts of lifestyle interventions on inflammation remain to be fully explained; however, epigenetic modifications may be critical. The purpose of our study was to investigate the impacts of eccentric resistance exercise and fatty acid supplementation on DNA methylation and mRNA expression of TNF and IL6 in skeletal muscle and leukocytes. Eight non-resistance exercise-trained males completed three bouts of isokinetic eccentric contractions of the knee extensors. The first bout occurred at baseline, the second occurred following a three-week supplementation of either omega-3 polyunsaturated fatty acid or extra virgin olive oil and the final bout occurred after eight-weeks of eccentric resistance training and supplementation. Acute exercise decreased skeletal muscle TNF DNA methylation by 5% (p = 0.031), whereas IL6 DNA methylation increased by 3% (p = 0.01). Leukocyte DNA methylation was unchanged following exercise (p > 0.05); however, three hours post-exercise the TNF DNA methylation decreased by 2% (p = 0.004). In skeletal muscle, increased TNF and IL6 mRNA expression levels were identified immediately post-exercise (p < 0.027); however, the leukocyte mRNA expression was unchanged. Associations between DNA methylation and markers of exercise performance, inflammation and muscle damage were identified (p < 0.05). Acute eccentric resistance exercise is sufficient to induce tissue-specific DNA methylation modifications to TNF and IL6; however, neither eccentric training nor supplementation was sufficient to further modify the DNA methylation.
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Affiliation(s)
- David John Hunter
- Translational Chemical Biology Research Group, School of Sport, Exercise and Health Sciences, Loughborough University, Epinal Way, Loughborough LE11 3TU, UK
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, Epinal Way, Loughborough LE11 3TU, UK
| | - Lynsey S. James
- Translational Chemical Biology Research Group, School of Sport, Exercise and Health Sciences, Loughborough University, Epinal Way, Loughborough LE11 3TU, UK
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, Epinal Way, Loughborough LE11 3TU, UK
| | - Bethan Hussey
- Translational Chemical Biology Research Group, School of Sport, Exercise and Health Sciences, Loughborough University, Epinal Way, Loughborough LE11 3TU, UK
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, Epinal Way, Loughborough LE11 3TU, UK
| | - Richard A. Ferguson
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, Epinal Way, Loughborough LE11 3TU, UK
| | - Martin R. Lindley
- Translational Chemical Biology Research Group, School of Sport, Exercise and Health Sciences, Loughborough University, Epinal Way, Loughborough LE11 3TU, UK
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, Epinal Way, Loughborough LE11 3TU, UK
- School of Biomedical Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Sarabjit S. Mastana
- Translational Chemical Biology Research Group, School of Sport, Exercise and Health Sciences, Loughborough University, Epinal Way, Loughborough LE11 3TU, UK
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, Epinal Way, Loughborough LE11 3TU, UK
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5
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Allen SL, Elliott BT, Carson BP, Breen L. Improving physiological relevance of cell culture: the possibilities, considerations, and future directions of the ex vivo coculture model. Am J Physiol Cell Physiol 2023; 324:C420-C427. [PMID: 36571441 PMCID: PMC9902212 DOI: 10.1152/ajpcell.00473.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 12/15/2022] [Accepted: 12/15/2022] [Indexed: 12/27/2022]
Abstract
In vitro models provide an important platform for the investigation of cellular growth and atrophy to inform, or extend mechanistic insights from, logistically challenging in vivo trials. Although these models allow for the identification of candidate mechanistic pathways, many models involve supraphysiological dosages, nonphysiological conditions, or experimental changes relating to individual proteins or receptors, all of which limit translation to human trials. To overcome these drawbacks, the use of ex vivo human plasma and serum has been used in cellular models to investigate changes in myotube hypertrophy, cellular protein synthesis, anabolic and catabolic markers in response to differing age, disease states, and nutrient status. However, there are currently no concurrent guidelines outlining the optimal methodology for this model. This review discusses the key methodological considerations surrounding the use of ex vivo plasma and serum with a focus in application to skeletal muscle cell lines (i.e., C2C12, L6, and LHCN-M2) and human primary skeletal muscle cells (HSMCs) as a means to investigate molecular signaling in models of atrophy and hypertrophy, alongside future directions.
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Affiliation(s)
- Sophie L Allen
- School of Sport Exercise and Rehabilitation Sciences, https://ror.org/03angcq70University of Birmingham, Birmingham, United Kingdom
- NIHR Birmingham Biomedical Research Centre, University Hospitals Birmingham NHS Foundation Trust, University of Birmingham, Birmingham, United Kingdom
| | - Bradley T Elliott
- Translational Physiology Research Group, School of Life Sciences, University of Westminster, London, United Kingdom
| | - Brian P Carson
- Department of Physical Education and Sport Sciences, Faculty of Education and Health Sciences, University of Limerick, Limerick, Ireland
- Health Research Institute, University of Limerick, Limerick, Ireland
| | - Leigh Breen
- School of Sport Exercise and Rehabilitation Sciences, https://ror.org/03angcq70University of Birmingham, Birmingham, United Kingdom
- NIHR Birmingham Biomedical Research Centre, University Hospitals Birmingham NHS Foundation Trust, University of Birmingham, Birmingham, United Kingdom
- MRC-Versus Arthritis Centre for Musculoskeletal Aging Research, University of Birmingham, Birmingham, United Kingdom
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6
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Lang CH. IMPORTANCE OF THE INNATE IMMUNE RESPONSE IN SKELETAL MUSCLE TO SEPSIS-INDUCED ALTERATIONS IN PROTEIN BALANCE. Shock 2023; 59:214-223. [PMID: 36730901 PMCID: PMC9957944 DOI: 10.1097/shk.0000000000002029] [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] [Indexed: 02/04/2023]
Abstract
ABSTRACT There is growing appreciation that skeletal muscle is a fully functional component of the body's innate immune system with the potential to actively participate in the host response to invading bacteria as opposed to being a passive target. In this regard, skeletal muscle in general and myocytes specifically possess an afferent limb that recognizes a wide variety of host pathogens via their interaction with multiple classes of cell membrane-bound and intracellular receptors, including toll-like receptors, cytokine receptors, NOD-like receptors, and the NLRP inflammasome. The efferent limb of the innate immune system in muscle is equally robust and with an increased synthesis and secretion of a variety of myocyte-derived cytokines (i.e., myokines), including TNF-α, IL-1, IL-6, and NO as well as multiple chemokines in response to appropriate stimulation. Herein, the current narrative review focuses primarily on the immune response of myocytes per se as opposed to other cell types within whole muscle. Moreover, because there are important differences, this review focuses specifically on systemic infection and inflammation as opposed to the response of muscle to direct injury and various types of muscular dystrophies. To date, however, there are few definitive muscle-specific studies that are necessary to directly address the relative importance of muscle-derived immune activation as a contributor to either the systemic immune response or the local immune microenvironment within muscle during sepsis and the resultant downstream metabolic disturbances.
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Affiliation(s)
- Charles H Lang
- Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
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7
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Waldemer-Streyer RJ, Kim D, Chen J. Muscle cell-derived cytokines in skeletal muscle regeneration. FEBS J 2022; 289:6463-6483. [PMID: 35073461 PMCID: PMC9308828 DOI: 10.1111/febs.16372] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 01/13/2022] [Accepted: 01/21/2022] [Indexed: 12/14/2022]
Abstract
Regeneration of the mammalian adult skeletal muscle is a well-orchestrated process regulated by multiple proteins and signalling pathways. Cytokines constitute a major class of regulators of skeletal myogenesis. It is well established that infiltrating immune cells at the site of muscle injury secrete cytokines, which play critical roles in the myofibre repair and regeneration process. In the past 10-15 years, skeletal muscle itself has emerged as a prolific producer of cytokines. Much attention in the field has been focused on the endocrine effects of muscle-secreted cytokines (myokines) on metabolic regulation. However, ample evidence suggests that muscle-derived cytokines also regulate myogenic differentiation and muscle regeneration in an autocrine manner. In this review, we survey cytokines that meet two criteria: (a) evidence of expression by muscle cells; (b) evidence demonstrating a myogenic function. Dozens of cytokines representing several major classes make up this group, and together they regulate all steps of the myogenic process. How such a large array of cytokines coordinate their signalling to form a regulatory network is a fascinating, pressing question. Functional studies that can distinguish the source of the cytokines in vivo are also much needed in order to facilitate exploration of their full therapeutic potential.
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Affiliation(s)
| | | | - Jie Chen
- Department of Cell & Developmental Biology, University of Illinois at Urbana-Champaign, 601 S. Goodwin Ave., Urbana, IL 61801
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8
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Wu KC, Chu PC, Cheng YJ, Li CI, Tian J, Wu HY, Wu SH, Lai YC, Kao HH, Hsu AL, Lin HW, Lin CH. Development of a traditional Chinese medicine-based agent for the treatment of cancer cachexia. J Cachexia Sarcopenia Muscle 2022; 13:2073-2087. [PMID: 35718751 PMCID: PMC9397559 DOI: 10.1002/jcsm.13028] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 04/19/2022] [Accepted: 05/13/2022] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Despite recent advances in understanding the pathophysiology of cancer cachexia, prevention/treatment of this debilitating disease remains an unmet medical need. METHODS We developed an integrated, multi-tiered strategy involving both in vitro and in vivo muscle atrophy platforms to identify traditional Chinese medicine (TCM)-based anti-cachectic agents. In the initial screening, we used inflammatory cytokine-induced atrophy of C2C12 myotubes as a phenotypic screening platform to assess the protective effects of TCMs. The selected TCMs were then evaluated for their abilities to protect Caenorhabditis elegans from age-related reduction of mobility and contractility, followed by the C-26 colon adenocarcinoma mouse model of cachexia to confirm the anti-muscle atrophy effects (body/skeletal muscle weights, fibre size distribution, grip strengths, and serum IL-6). Transcriptome analysis, quantitative real-time polymerase chain reaction, and immunoblotting were performed to gain understanding of the potential mechanism(s) by which effective TCM protected against C26 tumour-induced muscle atrophy. RESULTS Of 29 widely used TCMs, Dioscorea radix (DR) and Mu Dan Pi (MDP) showed a complete protection (all P values, 0.0002) vis-à-vis C26 conditioned medium control in the myotube atrophy platform. MDP exhibited a unique ability to ameliorate age-associated decreases in worm mobility, accompanied by improved total body contractions, relative to control (P < 0.0001 and <0.01, respectively), which, however, was not noted with DR. This differential in vivo protective effect between MDP and DR was also confirmed in the C-26 mouse model. MDP at 1000 mg/kg (MDP-H) was effective in protecting body weight loss (P < 0.05) in C-26 tumour-bearing mice without changing food or water intake, accompanied by the restoration of the fibre size distribution of hindleg skeletal muscles (P < 0.0001) and the forelimb grip strength (P < 0.05). MDP-treated C-26-tumour-bearing mice were alert, showed normal posture and better body conditions, and exhibited lower serum IL-6 levels (P = 0.06) relative to vehicle control. This decreased serum IL-6 was associated with the in vitro suppressive effect of MDP (25 and 50 μg/mL) on IL-6 secretion into culture medium by C26 cells. RNA-seq analysis, followed by quantitative real-time polymerase chain reaction and/or immunoblotting, shows that MDP's anti-cachectic effect was attributable to its ability to reverse the C-26 tumour-induced re-programming of muscle homoeostasis-associated gene expression, including that of two cachexia drivers (MuRF1 and Atrogin-1), in skeletal muscles. CONCLUSIONS All these findings suggest the translational potential of MDP to foster new strategies for the prevention and/or treatment of cachexia. The protective effect of MDP on other types of muscle atrophy such as sarcopenia might warrant investigations.
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Affiliation(s)
- Kun-Chang Wu
- School of Pharmacy, College of Pharmacy, China Medical University, Taichung, Taiwan.,Research Center for Healthy Aging, China Medical University, Taichung, Taiwan
| | - Po-Chen Chu
- Department of Cosmeceutics and Graduate Institute of Cosmeceutics, China Medical University, Taichung, Taiwan
| | - Yu-Jung Cheng
- Department of Physical Therapy and Graduate Institute of Rehabilitation Science, China Medical University, Taichung, Taiwan.,Department of Rehabilitation, China Medical University Hospital, Taichung, Taiwan
| | - Chia-Ing Li
- School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan.,Department of Medical Research, China Medical University Hospital, Taichung, Taiwan
| | - Jingkui Tian
- Institute of Cancer and Basic Medicine, Chinese Academy of Sciences, Cancer Hospital of the University of Chinese Academy of Sciences, Zhejiang Cancer Hospital, Hangzhou, China.,College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, China
| | - Hsing-Yu Wu
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Szu-Hsien Wu
- School of Pharmacy, College of Pharmacy, China Medical University, Taichung, Taiwan.,Institute of New Drug Development, China Medical University, Taichung, Taiwan
| | - Yi-Chun Lai
- Research Center for Healthy Aging, China Medical University, Taichung, Taiwan
| | - Hsiang-Han Kao
- Department of Family Medicine, China Medical University Hospital, Taichung, Taiwan
| | - Ao-Lin Hsu
- Research Center for Healthy Aging, China Medical University, Taichung, Taiwan.,PhD Program for Aging, China Medical University, Taichung, Taiwan.,Department of Internal Medicine, Division of Geriatrics & Palliative Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Hsiang-Wen Lin
- School of Pharmacy, College of Pharmacy, China Medical University, Taichung, Taiwan.,Department of Pharmacy, China Medical University Hospital, Taichung, Taiwan.,Department of Pharmacy System, Outcomes and Policy, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA
| | - Chih-Hsueh Lin
- School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan.,Department of Geriatric Medicine, China Medical University Hospital, Taichung, Taiwan
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Wu SE, Hsu JC, Chang YL, Chuang HC, Chiu YL, Chen WL. Benzo[a]pyrene exposure in muscle triggers sarcopenia through aryl hydrocarbon receptor-mediated reactive oxygen species production. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 239:113599. [PMID: 35567930 DOI: 10.1016/j.ecoenv.2022.113599] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 04/29/2022] [Accepted: 04/30/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Benzo[a]pyrene (BaP), a toxic carcinogen, is associated with various adverse effects but is rarely discussed in muscle-related disorders. This study investigated in vitro and in vivo effects triggered by BaP exposure in muscles and hypothesized that exposure might induce conditions similar to sarcopenia due to the shared mechanism of oxidative stress. In vitro experiments used C2C12 mouse myoblasts to examine effects induced by BaP exposure in control (untreated) and BaP-treated (10 µM/ml) muscle cells. An established TNF-α-treated sarcopenia model was utilized to verify our results. In vivo experiments compared immunohistochemical staining of sarcopenia-related markers in rats exposed to clean air and polluted air. RESULTS In C2C12 cells, after 2-72 h of BaP exposure, elevated mRNA and protein expressions were observed in aryl hydrocarbon receptor (AhR) and cytochrome P450 1A1, subsequently in ROS (NOX2 and NOX4) production, inflammatory cytokines (IL-6, TNF-α, and NF-kB), and proteins mediating apoptotic cell death (caspase-3 and PARP). Two myokines also altered mRNA and protein expressions akin to changes in sarcopenia, namely decreased irisin levels and increased myostatin levels. In addition, N-acetylcysteine, a well-known antioxidant, led to decrease in oxidative markers induced by BaP. The validation by TNF-α-treated sarcopenia model revealed comparable biological responses in either TNF-α or BaP treated C2C12 cells. In vivo experiments with rats exposed to air pollution showed increased expression of BaP, AhR, 8-hydroxydeoxyguanosine, and myostatin and decreased irisin expression in immunohistochemical staining. CONCLUSIONS Our results suggest that BaP exerts deleterious effects on the muscle, leading to conditions indicative of sarcopenia. Antioxidant supplementation may be a treatment option for BaP-induced sarcopenia, but further validation studies are needed.
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Affiliation(s)
- Shou-En Wu
- Department of Dermatology, Tri-Service General Hospital, School of Medicine, National Defense Medical Center, Taipei City, Taiwan (R.O.C); Division of Family Medicine, Department of Family and Community Medicine, Tri-Service General Hospital, School of Medicine, National Defense Medical Center, Taipei City, Taiwan (R.O.C); Division of Geriatric Medicine, Department of Family and Community Medicine, Tri-Service General Hospital, Taipei, Taiwan (R.O.C)
| | - Ju-Chun Hsu
- Department of Biochemistry, National Defense Medical Center, Taiwan (R.O.C)
| | - Yung-Lung Chang
- Department of Biochemistry, National Defense Medical Center, Taiwan (R.O.C)
| | - Hsiao-Chi Chuang
- School of Respiratory Therapy, College of Medicine, Taipei Medical University, Taipei, Taiwan (R.O.C); Division of Pulmonary Medicine, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan (R.O.C); Cell Physiology and Molecular Image Research Center, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan (R.O.C)
| | - Yi-Lin Chiu
- Department of Biochemistry, National Defense Medical Center, Taiwan (R.O.C)
| | - Wei-Liang Chen
- Division of Family Medicine, Department of Family and Community Medicine, Tri-Service General Hospital, School of Medicine, National Defense Medical Center, Taipei City, Taiwan (R.O.C); Division of Geriatric Medicine, Department of Family and Community Medicine, Tri-Service General Hospital, Taipei, Taiwan (R.O.C); Department of Biochemistry, National Defense Medical Center, Taiwan (R.O.C).
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10
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Coleman CS, Stanley BA, Lang CH. Enrichment of Newly Synthesized Proteins following treatment of C2C12 Myotubes with Endotoxin and Interferon-γ. Inflammation 2022; 45:1313-1331. [PMID: 35028803 PMCID: PMC9106851 DOI: 10.1007/s10753-022-01622-3] [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: 08/31/2021] [Revised: 12/17/2021] [Accepted: 01/04/2022] [Indexed: 11/28/2022]
Abstract
Inflammation in muscle induces the synthesis of mediators that can impair protein synthesis and enhance proteolysis, and when sustained lead to muscle atrophy. Furthermore, muscle-derived mediators that are secreted may participate in disrupting the function of other peripheral organs. Selective identification of newly synthesized proteins can provide insight on biological processes that depend on the continued synthesis of specific proteins to maintain homeostasis as well as those proteins that are up- or down-regulated in response to inflammation. We used puromycin-associated nascent chain proteomics (PUNCH-P) to characterize new protein synthesis in C2C12 myotubes and changes resulting from their exposure to the inflammatory mediators lipopolysaccharide (LPS) and interferon (IFN)-γ for either a short (4 h) or prolonged (16 h) time period. We identified sequences of nascent polypeptide chains belonging to a total of 1523 proteins and report their detection from three independent samples of each condition at each time point. The identified nascent proteins correspond to approximately 15% of presently known proteins in C2C12 myotubes and are enriched in specific cellular components and pathways. A subset of these proteins was identified only in treated samples and has functional characteristics consistent with the synthesis of specific new proteins in response to LPS/IFNγ. Thus, the identification of proteins from their nascent polypeptide chains provides a resource to analyze the role of new synthesis of proteins in both protein homeostasis and in proteome responses to stimuli in C2C12 myotubes. Our results reveal a profile of actively translating proteins for specific cellular components and biological processes in normal C2C12 myotubes and a different enrichment of proteins in response to LPS/IFNγ. Collectively, our data disclose a highly interconnected network that integrates the regulation of cellular proteostasis and reveal a diverse immune response to inflammation in muscle which may underlie the concomitantly observed atrophy and be important in inter-organ communication.
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Affiliation(s)
- Catherine S Coleman
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA, 17033, USA
| | - Bruce A Stanley
- Section of Research Resources, Penn State College of Medicine, Hershey, PA, 17033, USA
| | - Charles H Lang
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA, 17033, USA.
- Department of Surgery, Penn State College of Medicine, Hershey, PA, 17033, USA.
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11
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Allen SL, Marshall RN, Edwards SJ, Lord JM, Lavery GG, Breen L. The effect of young and old ex vivo human serum on cellular protein synthesis and growth in an in vitro model of aging. Am J Physiol Cell Physiol 2021; 321:C26-C37. [PMID: 33909501 DOI: 10.1152/ajpcell.00093.2021] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In vitro models of muscle aging are useful for understanding mechanisms of age-related muscle loss and aiding the development of targeted therapies. To investigate mechanisms of age-related muscle loss in vitro utilizing ex vivo human serum, fasted blood samples were obtained from four old (72 ± 1 yr) and four young (26 ± 3 yr) men. Older individuals had elevated levels of plasma CRP, IL-6, HOMA-IR, and lower concentric peak torque and work-per-repetition compared with young participants (P < 0.05). C2C12 myotubes were serum and amino acid starved for 1 h and conditioned with human serum (10%) for 4 h or 24 h. After 4 h, C2C12 cells were treated with 5 mM leucine for 30 min. Muscle protein synthesis (MPS) was determined through the surface sensing of translation (SUnSET) technique and regulatory signaling pathways were measured via Western blot. Myotube diameter was significantly reduced in myotubes treated with serum from old, in comparison to young donors (84%, P < 0.001). MPS was reduced in myotubes treated with old donor serum, compared with young serum before leucine treatment (32%, P < 0.01). MPS and the phosphorylation of Akt, p70S6K, and eEF2 were increased in myotubes treated with young serum in response to leucine treatment, with a blunted response identified in cells treated with old serum (P < 0.05). Muscle protein breakdown signaling pathways did not differ between groups. In summary, we show that myotubes conditioned with serum from older individuals had decreased myotube diameter and MPS compared with younger individuals, potentially driven by low-grade systemic inflammation.
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Affiliation(s)
- Sophie L Allen
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom.,National Institute for Health Research, Birmingham Biomedical Research Centre, University Hospitals Birmingham NHS Foundation Trust and University of Birmingham, Birmingham, United Kingdom
| | - Ryan N Marshall
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom.,MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham, United Kingdom
| | - Sophie J Edwards
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Janet M Lord
- National Institute for Health Research, Birmingham Biomedical Research Centre, University Hospitals Birmingham NHS Foundation Trust and University of Birmingham, Birmingham, United Kingdom.,MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham, United Kingdom.,Institute of Inflammation and Ageing, University of Birmingham, Birmingham, United Kingdom
| | - Gareth G Lavery
- National Institute for Health Research, Birmingham Biomedical Research Centre, University Hospitals Birmingham NHS Foundation Trust and University of Birmingham, Birmingham, United Kingdom.,MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham, United Kingdom.,Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom.,Centre for Endocrinology, Diabetes and Metabolism, Birmingham Health Partner, Birmingham, United Kingdom
| | - Leigh Breen
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom.,National Institute for Health Research, Birmingham Biomedical Research Centre, University Hospitals Birmingham NHS Foundation Trust and University of Birmingham, Birmingham, United Kingdom.,MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham, United Kingdom
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12
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Efficient and modified 2-NBDG assay to measure glucose uptake in cultured myotubes. J Pharmacol Toxicol Methods 2021; 109:107069. [PMID: 33892108 DOI: 10.1016/j.vascn.2021.107069] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 04/12/2021] [Accepted: 04/16/2021] [Indexed: 12/23/2022]
Abstract
Under type-2 diabetes, insulin resistance develops in skeletal muscles as a key defect and to study the disorder, its manifestation, and possible solution, measurement of glucose uptake is a fundamental necessity. Of various approaches (i.e. scintillation counting, flow cytometry, fluorometry and spectrophotometry) fluorescent labelled glucose analogue, 2-NBDG solution is the most popular one. Although 2-NBDG based assay is the most widely used approach in various cells including skeletal muscle, even then all available protocols possess huge variability which impacts the overall data reproducibility. Moreover, starvation (use of glucose/serum free medium), one of the prerequisite condition for glucose uptake assay, itself induces stress specifically during longer pre-incubation periods and alters muscle cell metabolism and morphology, but the fact has not been duly considered. Therefore in the present article, using specific skeletal muscle cells i.e. C2C12 myotubes, we have re-established the conditions like pre-incubation time period, concentrations of insulin, glucose and serum/BSA while maintaining the cultured myotubes in morphologically healthy state. Our lab standardized protocols were observed to be effective in studying insulin resistance condition induced by diverse stresses (oxidative & inflammation) in myotubes. Comparative study conducted with already established protocols demonstrates that the present method is more efficient, effective and better improvised for studying glucose uptake in C2C12.
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13
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Turner DC, Gorski PP, Maasar MF, Seaborne RA, Baumert P, Brown AD, Kitchen MO, Erskine RM, Dos-Remedios I, Voisin S, Eynon N, Sultanov RI, Borisov OV, Larin AK, Semenova EA, Popov DV, Generozov EV, Stewart CE, Drust B, Owens DJ, Ahmetov II, Sharples AP. DNA methylation across the genome in aged human skeletal muscle tissue and muscle-derived cells: the role of HOX genes and physical activity. Sci Rep 2020; 10:15360. [PMID: 32958812 PMCID: PMC7506549 DOI: 10.1038/s41598-020-72730-z] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 09/04/2020] [Indexed: 12/15/2022] Open
Abstract
Skeletal muscle tissue demonstrates global hypermethylation with age. However, methylome changes across the time-course of differentiation in aged human muscle derived cells, and larger coverage arrays in aged muscle tissue have not been undertaken. Using 850K DNA methylation arrays we compared the methylomes of young (27 ± 4.4 years) and aged (83 ± 4 years) human skeletal muscle and that of young/aged heterogenous muscle-derived human primary cells (HDMCs) over several time points of differentiation (0, 72 h, 7, 10 days). Aged muscle tissue was hypermethylated compared with young tissue, enriched for; pathways-in-cancer (including; focal adhesion, MAPK signaling, PI3K-Akt-mTOR signaling, p53 signaling, Jak-STAT signaling, TGF-beta and notch signaling), rap1-signaling, axon-guidance and hippo-signalling. Aged cells also demonstrated a hypermethylated profile in pathways; axon-guidance, adherens-junction and calcium-signaling, particularly at later timepoints of myotube formation, corresponding with reduced morphological differentiation and reductions in MyoD/Myogenin gene expression compared with young cells. While young cells showed little alterations in DNA methylation during differentiation, aged cells demonstrated extensive and significantly altered DNA methylation, particularly at 7 days of differentiation and most notably in focal adhesion and PI3K-AKT signalling pathways. While the methylomes were vastly different between muscle tissue and HDMCs, we identified a small number of CpG sites showing a hypermethylated state with age, in both muscle tissue and cells on genes KIF15, DYRK2, FHL2, MRPS33, ABCA17P. Most notably, differential methylation analysis of chromosomal regions identified three locations containing enrichment of 6–8 CpGs in the HOX family of genes altered with age. With HOXD10, HOXD9, HOXD8, HOXA3, HOXC9, HOXB1, HOXB3, HOXC-AS2 and HOXC10 all hypermethylated in aged tissue. In aged cells the same HOX genes (and additionally HOXC-AS3) displayed the most variable methylation at 7 days of differentiation versus young cells, with HOXD8, HOXC9, HOXB1 and HOXC-AS3 hypermethylated and HOXC10 and HOXC-AS2 hypomethylated. We also determined that there was an inverse relationship between DNA methylation and gene expression for HOXB1, HOXA3 and HOXC-AS3. Finally, increased physical activity in young adults was associated with oppositely regulating HOXB1 and HOXA3 methylation compared with age. Overall, we demonstrate that a considerable number of HOX genes are differentially epigenetically regulated in aged human skeletal muscle and HDMCs and increased physical activity may help prevent age-related epigenetic changes in these HOX genes.
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Affiliation(s)
- D C Turner
- Institute for Physical Performance, Norwegian School of Sport Sciences (NiH), Oslo, Norway.,Stem Cells, Ageing and Molecular Physiology Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK.,Institute for Science and Technology in Medicine (ISTM), School of Pharmacy & Bioengineering, Keele University, Staffordshire, UK
| | - P P Gorski
- Institute for Physical Performance, Norwegian School of Sport Sciences (NiH), Oslo, Norway.,Institute for Science and Technology in Medicine (ISTM), School of Pharmacy & Bioengineering, Keele University, Staffordshire, UK
| | - M F Maasar
- Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - R A Seaborne
- Stem Cells, Ageing and Molecular Physiology Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK.,Institute for Science and Technology in Medicine (ISTM), School of Pharmacy & Bioengineering, Keele University, Staffordshire, UK.,Centre for Genomics and Child Health, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - P Baumert
- Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK.,Exercise Biology Group, Faculty of Sport and Health Sciences, Technical University of Munich, Munich, Germany
| | - A D Brown
- Stem Cells, Ageing and Molecular Physiology Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - M O Kitchen
- Institute for Science and Technology in Medicine (ISTM), School of Pharmacy & Bioengineering, Keele University, Staffordshire, UK
| | - R M Erskine
- Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK.,Institute of Sport, Exercise and Health, University College London, London, UK
| | - I Dos-Remedios
- Orthopedics Department, University Hospitals of the North Midlands, Keele University, Staffordshire, UK
| | - S Voisin
- Institute for Health and Sport (iHeS), Victoria University, Footscray, VIC, Australia
| | - N Eynon
- Institute for Health and Sport (iHeS), Victoria University, Footscray, VIC, Australia
| | - R I Sultanov
- Department of Molecular Biology and Genetics, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, Russia
| | - O V Borisov
- Department of Molecular Biology and Genetics, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, Russia.,Institute for Genomic Statistics and Bioinformatics, University Hospital Bonn, Bonn, Germany
| | - A K Larin
- Department of Molecular Biology and Genetics, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, Russia
| | - E A Semenova
- Department of Molecular Biology and Genetics, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, Russia
| | - D V Popov
- Laboratory of Exercise Physiology, Institute of Biomedical Problems of the Russian Academy of Sciences, Moscow, Russia
| | - E V Generozov
- Department of Molecular Biology and Genetics, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, Russia
| | - C E Stewart
- Stem Cells, Ageing and Molecular Physiology Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - B Drust
- School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, UK
| | - D J Owens
- Stem Cells, Ageing and Molecular Physiology Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK.,Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - I I Ahmetov
- Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK. .,Laboratory of Molecular Genetics, Kazan State Medical University, Kazan, Russia. .,Department of Physical Education, Plekhanov Russian University of Economics, Moscow, Russia.
| | - A P Sharples
- Institute for Physical Performance, Norwegian School of Sport Sciences (NiH), Oslo, Norway. .,Stem Cells, Ageing and Molecular Physiology Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK. .,Institute for Science and Technology in Medicine (ISTM), School of Pharmacy & Bioengineering, Keele University, Staffordshire, UK.
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14
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Wong CY, Al-Salami H, Dass CR. C2C12 cell model: its role in understanding of insulin resistance at the molecular level and pharmaceutical development at the preclinical stage. J Pharm Pharmacol 2020; 72:1667-1693. [PMID: 32812252 DOI: 10.1111/jphp.13359] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 07/17/2020] [Accepted: 07/25/2020] [Indexed: 12/11/2022]
Abstract
OBJECTIVES The myoblast cell line, C2C12, has been utilised extensively in vitro as an examination model in understanding metabolic disease progression. Although it is indispensable in both preclinical and pharmaceutical research, a comprehensive review of its use in the investigation of insulin resistance progression and pharmaceutical development is not available. KEY FINDINGS C2C12 is a well-documented model, which can facilitate our understanding in glucose metabolism, insulin signalling mechanism, insulin resistance, oxidative stress, reactive oxygen species and glucose transporters at cellular and molecular levels. With the aid of the C2C12 model, recent studies revealed that insulin resistance has close relationship with various metabolic diseases in terms of disease progression, pathogenesis and therapeutic management. A holistic, safe and effective disease management is highly of interest. Therefore, significant efforts have been paid to explore novel drug compounds and natural herbs that can elicit therapeutic effects in the targeted sites at both cellular (e.g. mitochondria, glucose transporter) and molecular level (e.g. genes, signalling pathway). SUMMARY The use of C2C12 myoblast cell line is meaningful in pharmaceutical and biomedical research due to their expression of GLUT-4 and other features that are representative to human skeletal muscle cells. With the use of the C2C12 cell model, the impact of drug delivery systems (nanoparticles and quantum dots) on skeletal muscle, as well as the relationship between exercise, pancreatic β-cells and endothelial cells, was discovered.
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Affiliation(s)
- Chun Y Wong
- School of Pharmacy and Biomedical Science, Curtin University, Bentley, WA, Australia.,Curtin Health Innovation Research Institute, Bentley, WA, Australia
| | - Hani Al-Salami
- School of Pharmacy and Biomedical Science, Curtin University, Bentley, WA, Australia.,Curtin Health Innovation Research Institute, Bentley, WA, Australia.,Biotechnology and Drug Development Research Laboratory, Curtin University, Bentley, WA, Australia
| | - Crispin R Dass
- School of Pharmacy and Biomedical Science, Curtin University, Bentley, WA, Australia.,Curtin Health Innovation Research Institute, Bentley, WA, Australia
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15
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Ghnaimawi S, Baum J, Liyanage R, Huang Y. Concurrent EPA and DHA Supplementation Impairs Brown Adipogenesis of C2C12 Cells. Front Genet 2020; 11:531. [PMID: 32595696 PMCID: PMC7303889 DOI: 10.3389/fgene.2020.00531] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 05/01/2020] [Indexed: 12/27/2022] Open
Abstract
Maternal dietary supplementation of n−3 polyunsaturated fatty acids (n−3 PUFAs), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), is considered to play positive roles in fetal neuro system development. However, maternal n−3 PUFAs may induce molecular reprogramming of uncommitted fetal myoblasts into adipocyte phenotype, in turn affecting lipid metabolism and energy expenditure of the offspring. The objective of this in vitro study was to investigate the combined effects of EPA and DHA on C2C12 cells undergoing brown adipogenic differentiation. C2C12 myoblasts were cultured to confluency and then treated with brown adipogenic differentiation medium with and without 50 μM EPA and 50 μM DHA. After differentiation, mRNA and protein samples were collected. Gene expression and protein levels were analyzed by real-time PCR and western blot. General Proteomics analysis was conducted using mass spectrometric evaluation. The effect of EPA and DHA on cellular oxygen consumption was measured using a Seahorse XFP Analyzer. Cells treated with n−3 PUFAs had significantly less (P < 0.05) expression of the brown adipocyte marker genes PGC1α, DIO2, and UCP3. Expression of mitochondrial biogenesis-related genes TFAM, PGC1α, and PGC1β were significantly downregulated (P < 0.05) by n−3 PUFAs treatment. Expression of mitochondrial electron transportation chain (ETC)-regulated genes were significantly inhibited (P < 0.05) by n−3 PUFAs, including ATP5J2, COX7a1, and COX8b. Mass spectrometric and western blot evaluation showed protein levels of enzymes which regulate the ETC and Krebs cycle, including ATP synthase α and β (F1F0 complex), citrate synthase, succinate CO-A ligase, succinate dehydrogenase (complex II), ubiquinol-cytochrome c reductase complex subunits (complex III), aconitate hydratase, cytochrome c, and pyruvate carboxylase were all decreased in the n−3 PUFAs group (P < 0.05). Genomic and proteomic changes were accompanied by mitochondrial dysfunction, represented by significantly reduced oxygen consumption rate, ATP production, and proton leak (P < 0.05). This study suggested that EPA and DHA may alter the BAT fate of myoblasts by inhibiting mitochondrial biogenesis and activity and induce white-like adipogenesis, shifting the metabolism from lipid oxidation to synthesis.
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Affiliation(s)
- Saeed Ghnaimawi
- Department of Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR, United States
| | - Jamie Baum
- Department of Food Science, Division of Agriculture, University of Arkansas, Fayetteville, AR, United States
| | - Rohana Liyanage
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR, United States
| | - Yan Huang
- Department of Animal Science, Division of Agriculture, University of Arkansas, Fayetteville, AR, United States
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16
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Rimington RP, Capel AJ, Chaplin KF, Fleming JW, Bandulasena HCH, Bibb RJ, Christie SDR, Lewis MP. Differentiation of Bioengineered Skeletal Muscle within a 3D Printed Perfusion Bioreactor Reduces Atrophic and Inflammatory Gene Expression. ACS Biomater Sci Eng 2019; 5:5525-5538. [PMID: 33464072 DOI: 10.1021/acsbiomaterials.9b00975] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Bioengineered skeletal muscle tissues benefit from dynamic culture environments which facilitate the appropriate provision of nutrients and removal of cellular waste products. Biologically compatible perfusion systems hold the potential to enhance the physiological biomimicry of in vitro tissues via dynamic culture, in addition to providing technological advances in analytical testing and live cellular imaging for analysis of cellular development. To meet such diverse requirements, perfusion systems require the capacity and adaptability to incorporate multiple cell laden constructs of both monolayer and bioengineered tissues. This work reports perfusion systems produced using additive manufacturing technology for the in situ phenotypic development of myogenic precursor cells in monolayer and bioengineered tissue. Biocompatibility of systems 3D printed using stereolithography (SL), laser sintering (LS), and PolyJet outlined preferential morphological development within both SL and LS devices. When exposed to intermittent perfusion in the monolayer, delayed yet physiologically representative cellular proliferation, MyoD and myogenin transcription of C2C12 cells was evident. Long-term (8 days) intermittent perfusion of monolayer cultures outlined viable morphological and genetic in situ differentiation for the live cellular imaging of myogenic development. Continuous perfusion cultures (13 days) of bioengineered skeletal muscle tissues outlined in situ myogenic differentiation, forming mature multinucleated myotubes. Here, reductions in IL-1β and TNF-α inflammatory cytokines, myostatin, and MuRF-1 atrophic mRNA expression were observed. Comparable myosin heavy chain (MyHC) isoform transcription profiles were evident between conditions; however, total mRNA expression was reduced in perfusion conditions. Decreased transcription of MuRF1 and subsequent reduced ubiquitination of the MyHC protein allude to a decreased requirement for transcription of MyHC isoform transcripts. Together, these data appear to indicate that 3D printed perfusion systems elicit enhanced stability of the culture environment, resulting in a reduced basal requirement for MyHC gene expression within bioengineered skeletal muscle tissue.
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17
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Peng Y, Sun Q, Park Y. Chicoric acid promotes glucose uptake and Akt phosphorylation via AMP-activated protein kinase α-dependent pathway. J Funct Foods 2019. [DOI: 10.1016/j.jff.2019.05.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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18
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Shan T, Liu J, Xu Z, Wang Y. Roles of phosphatase and tensin homolog in skeletal muscle. J Cell Physiol 2018; 234:3192-3196. [DOI: 10.1002/jcp.26820] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Accepted: 04/30/2018] [Indexed: 12/16/2022]
Affiliation(s)
- Tizhong Shan
- Institute of Feed Science, College of Animal Sciences Zhejiang University Hangzhou China
- The Key Laboratory of Molecular Animal Nutrition Ministry of Education Hangzhou China
- Zhejiang Provincial Laboratory of Feed and Animal Nutrition Hangzhou China
| | - Jiaqi Liu
- Institute of Feed Science, College of Animal Sciences Zhejiang University Hangzhou China
- The Key Laboratory of Molecular Animal Nutrition Ministry of Education Hangzhou China
- Zhejiang Provincial Laboratory of Feed and Animal Nutrition Hangzhou China
| | - Ziye Xu
- Institute of Feed Science, College of Animal Sciences Zhejiang University Hangzhou China
- The Key Laboratory of Molecular Animal Nutrition Ministry of Education Hangzhou China
- Zhejiang Provincial Laboratory of Feed and Animal Nutrition Hangzhou China
| | - Yizhen Wang
- Institute of Feed Science, College of Animal Sciences Zhejiang University Hangzhou China
- The Key Laboratory of Molecular Animal Nutrition Ministry of Education Hangzhou China
- Zhejiang Provincial Laboratory of Feed and Animal Nutrition Hangzhou China
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19
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Feasibility and Biocompatibility of 3D-Printed Photopolymerized and Laser Sintered Polymers for Neuronal, Myogenic, and Hepatic Cell Types. Macromol Biosci 2018; 18:e1800113. [DOI: 10.1002/mabi.201800113] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 04/24/2018] [Indexed: 12/14/2022]
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20
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Sawicka AK, Hartmane D, Lipinska P, Wojtowicz E, Lysiak-Szydlowska W, Olek RA. l-Carnitine Supplementation in Older Women. A Pilot Study on Aging Skeletal Muscle Mass and Function. Nutrients 2018; 10:nu10020255. [PMID: 29473908 PMCID: PMC5852831 DOI: 10.3390/nu10020255] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Revised: 02/02/2018] [Accepted: 02/17/2018] [Indexed: 12/21/2022] Open
Abstract
Skeletal muscle wasting, associated with aging, may be regulated by the inflammatory cytokines as well as by insulin-like growth factor 1 (IGF-1). l-carnitine possesses anti-inflammatory properties and increases plasma IGF-1 concentration, leading to the regulation of the genes responsible for protein catabolism and anabolism. The purpose of the present study was to evaluate the effect of a 24-week l-carnitine supplementation on serum inflammatory markers, IGF-1, body composition and skeletal muscle strength in healthy human subjects over 65 years of age. Women between 65 and 70 years of age were supplemented for 24 weeks with either 1500 mg l-carnitine-l-tartrate or an isonitrogenous placebo per day in a double-blind fashion. Before and after the supplementation protocol, body mass and composition, as well as knee extensor and flexor muscle strength were determined. In the blood samples, free carnitine, interleukin-6, tumor necrosis factor-α, C-reactive protein and IGF-1 were determined. A marked increase in free plasma carnitine concentration was observed due to l-carnitine supplementation. No substantial changes in other parameters were noted. In the current study, supplementation for 24 weeks affected neither the skeletal muscle strength nor circulating markers in healthy women over 65 years of age. Positive and negative aspects of l-carnitine supplementation need to be clarified.
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Affiliation(s)
- Angelika K Sawicka
- Department of Bioenergetics and Nutrition, Gdansk University of Physical Education and Sport, 80-336 Gdansk, Poland.
| | - Dace Hartmane
- Latvian Institute of Organic Synthesis, LV-1006 Riga, Latvia.
| | - Patrycja Lipinska
- Institute of Physical Culture, Kazimierz Wielki University, 85-091 Bydgoszcz, Poland.
| | - Ewa Wojtowicz
- Department of Anatomy and Anthropology, Gdansk University of Physical Education and Sport, 80-336 Gdansk, Poland.
| | | | - Robert A Olek
- Department of Bioenergetics and Nutrition, Gdansk University of Physical Education and Sport, 80-336 Gdansk, Poland.
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21
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Dugdale HF, Hughes DC, Allan R, Deane CS, Coxon CR, Morton JP, Stewart CE, Sharples AP. The role of resveratrol on skeletal muscle cell differentiation and myotube hypertrophy during glucose restriction. Mol Cell Biochem 2017; 444:109-123. [PMID: 29189984 PMCID: PMC6002440 DOI: 10.1007/s11010-017-3236-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 11/24/2017] [Indexed: 12/01/2022]
Abstract
Glucose restriction (GR) impairs muscle cell differentiation and evokes myotube atrophy. Resveratrol treatment in skeletal muscle cells improves inflammatory-induced reductions in skeletal muscle cell differentiation. We therefore hypothesised that resveratrol treatment would improve muscle cell differentiation and myotube hypertrophy in differentiating C2C12 myoblasts and mature myotubes during GR. Glucose restriction at 0.6 g/L (3.3 mM) blocked differentiation and myotube hypertrophy versus high-glucose (4.5 g/L or 25 mM) differentiation media (DM) conditions universally used for myoblast culture. Resveratrol (10 µM) treatment increased SIRT1 phosphorylation in DM conditions, yet did not improve differentiation when administered to differentiating myoblasts in GR conditions. Resveratrol did evoke increases in hypertrophy of mature myotubes under DM conditions with corresponding elevated Igf-I and Myhc7 gene expression, coding for the ‘slow’ type I MYHC protein isoform. Inhibition of SIRT1 via EX-527 administration (100 nM) also reduced myotube diameter and area in DM conditions and resulted in lower gene expression of Myhc 1, 2 and 4 coding for ‘intermediate’ and ‘faster’ IIx, IIa and IIb protein isoforms, respectively. Resveratrol treatment did not appear to modulate phosphorylation of energy-sensing protein AMPK or protein translation initiator P70S6K. Importantly, in mature myotubes, resveratrol treatment was able to ameliorate reduced myotube growth in GR conditions over an acute 24-h period, but not over 48–72 h. Overall, resveratrol evoked myotube hypertrophy in DM conditions while favouring ‘slower’ Myhc gene expression and acutely ameliorated impaired myotube growth observed during glucose restriction.
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Affiliation(s)
- Hannah F Dugdale
- Stem Cells, Ageing and Molecular Physiology Research (SCAMP) Unit, Exercise Metabolism and Adaptation Research Group (EMARG), Research Institute for Sport and Exercise Sciences (RISES), Liverpool John Moores University, Liverpool, UK
| | - David C Hughes
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Carver College of Medicine, University of Iowa, Iowa City, IA, 52246, USA
| | - Robert Allan
- Centre for Applied Sport and Exercise Sciences, University of Central Lancashire, Preston, UK
| | - Colleen S Deane
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Christopher R Coxon
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, UK
| | - James P Morton
- Stem Cells, Ageing and Molecular Physiology Research (SCAMP) Unit, Exercise Metabolism and Adaptation Research Group (EMARG), Research Institute for Sport and Exercise Sciences (RISES), Liverpool John Moores University, Liverpool, UK
| | - Claire E Stewart
- Stem Cells, Ageing and Molecular Physiology Research (SCAMP) Unit, Exercise Metabolism and Adaptation Research Group (EMARG), Research Institute for Sport and Exercise Sciences (RISES), Liverpool John Moores University, Liverpool, UK
| | - Adam P Sharples
- Institute for Science and Technology in Medicine (ISTM), School of Medicine, Keele University, The Guy Hilton Research Centre, Thornburrow Drive, Hartshill, Staffordshire, ST4 7QB, UK. .,Stem Cells, Ageing and Molecular Physiology Research (SCAMP) Unit, Exercise Metabolism and Adaptation Research Group (EMARG), Research Institute for Sport and Exercise Sciences (RISES), Liverpool John Moores University, Liverpool, UK.
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22
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Rimington RP, Capel AJ, Christie SDR, Lewis MP. Biocompatible 3D printed polymers via fused deposition modelling direct C 2C 12 cellular phenotype in vitro. LAB ON A CHIP 2017; 17:2982-2993. [PMID: 28762415 DOI: 10.1039/c7lc00577f] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The capability to 3D print bespoke biologically receptive parts within short time periods has driven the growing prevalence of additive manufacture (AM) technology within biological settings, however limited research concerning cellular interaction with 3D printed polymers has been undertaken. In this work, we used skeletal muscle C2C12 cell line in order to ascertain critical evidence of cellular behaviour in response to multiple bio-receptive candidate polymers; polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), polyethylene terephthalate (PET) and polycarbonate (PC) 3D printed via fused deposition modelling (FDM). The extrusion based nature of FDM elicited polymer specific topographies, within which C2C12 cells exhibited reduced metabolic activity when compared to optimised surfaces of tissue culture plastic, however assay viability readings remained high across polymers outlining viable phenotypes. C2C12 cells exhibited consistently high levels of morphological alignment across polymers, however differential myotube widths and levels of transcriptional myogenin expression appeared to demonstrate response specific thresholds at which varying polymer selection potentiates cellular differentiation, elicits pre-mature early myotube formation and directs subsequent morphological phenotype. Here we observed biocompatible AM polymers manufactured via FDM, which also appear to hold the potential to simultaneously manipulate the desired biological phenotype and enhance the biomimicry of skeletal muscle cells in vitro via AM polymer choice and careful selection of machine processing parameters. When considered in combination with the associated design freedom of AM, this may provide the opportunity to not only enhance the efficiency of creating biomimetic models, but also to precisely control the biological output within such scaffolds.
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Affiliation(s)
- Rowan P Rimington
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, Leicestershire LE11 3TU, UK.
| | - Andrew J Capel
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, Leicestershire LE11 3TU, UK. and Department of Chemistry, School of Science, Loughborough University, Loughborough, Leicestershire LE11 3TU, UK
| | - Steven D R Christie
- Department of Chemistry, School of Science, Loughborough University, Loughborough, Leicestershire LE11 3TU, UK
| | - Mark P Lewis
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, Leicestershire LE11 3TU, UK.
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23
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Yu Y, Fu L, Wang S, Jin Y, Han S, Chu P, Lu J, Guo Y, He L, Ni X. Investigation of IGF2, IGFBP2 and p63 proteins in rhabdomyosarcoma tumors. Growth Horm IGF Res 2017; 33:17-22. [PMID: 28129571 DOI: 10.1016/j.ghir.2017.01.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 01/12/2017] [Accepted: 01/12/2017] [Indexed: 12/21/2022]
Abstract
UNLABELLED Many efforts have been made to address involvement of the insulin-like growth-factor (IGF) pathway in rhabdomyosarcoma (RMS) pathogenesis, but the actual role of IGF in RMS is still controversial. OBJECTIVE To investigate the implications of IGF2, IGFBP2 and p63 in RMS, and further explored their potential interaction. DESIGN A total of 114 specimens of RMS along with clinic-pathologic characteristics were collected from the year of 2003 to 2013. Protein abundance was detected by immunohistochemical staining, potential relationships between protein levels and clinic-pathological parameters were applied using correlation analysis. RESULTS The results showed positive correlation between IGFBP2 and p63 (r=0.271, p=0.003), suggesting that the interaction of IGFBP2 and p63 might account for the pathogenesis of RMS. In the subtype analysis, positive correlation was still found in embryonal rhabdomyosarcoma (ERMS, r=0.214, p=0.034) and alveolar rhabdomyosarcoma (ARMS, r=0.498, p=0.048). By focusing on the interaction of IGF pathway and p63, our results reveal additional signs to elucidate difference of pathogenesis and severity between ERMS and ARMS. CONCLUSIONS The present study provides novel evidence to elucidate RMS pathogenesis and may be beneficial to clinical diagnosis and therapy for RMS.
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Affiliation(s)
- Yongbo Yu
- Beijing Key Laboratory for Pediatric Diseases of Otolaryngology, Head and Neck Surgery, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Libing Fu
- Beijing Key Laboratory for Pediatric Diseases of Otolaryngology, Head and Neck Surgery, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Shen Wang
- Clinical Diagnostic Center, 302nd Hospital of the People's Liberation Army, Beijing, China
| | - Yaqiong Jin
- Beijing Key Laboratory for Pediatric Diseases of Otolaryngology, Head and Neck Surgery, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Shujing Han
- Beijing Key Laboratory for Pediatric Diseases of Otolaryngology, Head and Neck Surgery, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Ping Chu
- Beijing Key Laboratory for Pediatric Diseases of Otolaryngology, Head and Neck Surgery, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Jie Lu
- Beijing Key Laboratory for Pediatric Diseases of Otolaryngology, Head and Neck Surgery, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Yongli Guo
- Beijing Key Laboratory for Pediatric Diseases of Otolaryngology, Head and Neck Surgery, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Lejian He
- Department of Pathology, Beijing Children's Hospital, Capital Medical University, Beijing, China.
| | - Xin Ni
- Beijing Key Laboratory for Pediatric Diseases of Otolaryngology, Head and Neck Surgery, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing, China; Department of Otolaryngology, Head and Neck Surgery, Beijing Children's Hospital, Capital Medical University, Beijing, China.
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24
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Kasper AM, Turner DC, Martin NRW, Sharples AP. Mimicking exercise in three-dimensional bioengineered skeletal muscle to investigate cellular and molecular mechanisms of physiological adaptation. J Cell Physiol 2017; 233:1985-1998. [DOI: 10.1002/jcp.25840] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 02/02/2017] [Indexed: 12/22/2022]
Affiliation(s)
- Andreas M. Kasper
- Stem Cells, Ageing, and Molecular Physiology (SCAMP) Unit, Exercise Metabolism and Adaptation Research group, Research Institute for Sport and Exercise Sciences (RISES), School of Sport and Exercise Sciences; Liverpool John Moores University; Liverpool UK
| | - Daniel C. Turner
- Stem Cells, Ageing, and Molecular Physiology (SCAMP) Unit, Exercise Metabolism and Adaptation Research group, Research Institute for Sport and Exercise Sciences (RISES), School of Sport and Exercise Sciences; Liverpool John Moores University; Liverpool UK
| | - Neil R. W. Martin
- Musculoskeletal Biology Research Group, School of Sport, Exercise, and Health Sciences; Loughborough University; Loughborough UK
| | - Adam P. Sharples
- Stem Cells, Ageing, and Molecular Physiology (SCAMP) Unit, Exercise Metabolism and Adaptation Research group, Research Institute for Sport and Exercise Sciences (RISES), School of Sport and Exercise Sciences; Liverpool John Moores University; Liverpool UK
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25
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Soriano-Arroquia A, Clegg PD, Molloy AP, Goljanek-Whysall K. Preparation and Culture of Myogenic Precursor Cells/Primary Myoblasts from Skeletal Muscle of Adult and Aged Humans. J Vis Exp 2017. [PMID: 28287512 PMCID: PMC5408649 DOI: 10.3791/55047] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Skeletal muscle homeostasis depends on muscle growth (hypertrophy), atrophy and regeneration. During ageing and in several diseases, muscle wasting occurs. Loss of muscle mass and function is associated with muscle fiber type atrophy, fiber type switching, defective muscle regeneration associated with dysfunction of satellite cells, muscle stem cells, and other pathophysiological processes. These changes are associated with changes in intracellular as well as local and systemic niches. In addition to most commonly used rodent models of muscle ageing, there is a need to study muscle homeostasis and wasting using human models, which due to ethical implications, consist predominantly of in vitro cultures. Despite the wide use of human Myogenic Progenitor Cells (MPCs) and primary myoblasts in myogenesis, there is limited data on using human primary myoblast and myotube cultures to study molecular mechanisms regulating different aspects of age-associated muscle wasting, aiding in the validation of mechanisms of ageing proposed in rodent muscle. The use of human MPCs, primary myoblasts and myotubes isolated from adult and aged people, provides a physiologically relevant model of molecular mechanisms of processes associated with muscle growth, atrophy and regeneration. Here we describe in detail a robust, inexpensive, reproducible and efficient protocol for the isolation and maintenance of human MPCs and their progeny — myoblasts and myotubes from human muscle samples using enzymatic digestion. Furthermore, we have determined the passage number at which primary myoblasts from adult and aged people undergo senescence in an in vitro culture. Finally, we show the ability to transfect these myoblasts and the ability to characterize their proliferative and differentiation capacity and propose their suitability for performing functional studies of molecular mechanisms of myogenesis and muscle wasting in vitro.
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Affiliation(s)
| | - Peter D Clegg
- Institute of Ageing and Chronic Disease, University of Liverpool
| | - Andrew P Molloy
- Institute of Ageing and Chronic Disease, University of Liverpool; Aintree University Hospital
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26
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Saini A, Sharples AP, Al-Shanti N, Stewart CE. Omega-3 fatty acid EPA improves regenerative capacity of mouse skeletal muscle cells exposed to saturated fat and inflammation. Biogerontology 2016; 18:109-129. [PMID: 27864687 PMCID: PMC5288450 DOI: 10.1007/s10522-016-9667-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 11/05/2016] [Indexed: 12/17/2022]
Abstract
Sarcopenic obesity is characterised by high fat mass, low muscle mass and an elevated inflammatory environmental milieu. We therefore investigated the effects of elevated inflammatory cytokine TNF-α (aging/obesity) and saturated fatty acid, palmitate (obesity) on skeletal muscle cells in the presence/absence of EPA, a-3 polyunsaturated fatty acid with proposed anti-inflammatory, anti-obesity activities. In the present study we show that palmitate was lipotoxic, inducing high levels of cell death and blocking myotube formation. Cell death under these conditions was associated with increased caspase activity, suppression of differentiation, reductions in both creatine kinase activity and gene expression of myogenic factors; IGF-II, IGFBP-5, MyoD and myogenin. However, inhibition of caspase activity via administration of Z-VDVAD-FMK (caspase-2), Z-DEVD-FMK (caspase-3) and ZIETD-KMK (caspase 8) was without effect on cell death. By contrast, lipotoxicity associated with elevated palmitate was reduced with the MEK inhibitor PD98059, indicating palmitate induced cell death was MAPK mediated. These lipotoxic conditions were further exacerbated in the presence of inflammation via TNF-α co-administration. Addition of EPA under cytotoxic stress (TNF-α) was shown to partially rescue differentiation with enhanced myotube formation being associated with increased MyoD, myogenin, IGF-II and IGFBP-5 expression. EPA had little impact on the cell death phenotype observed in lipotoxic conditions but did show benefit in restoring differentiation under lipotoxic plus cytotoxic conditions. Under these conditions Id3 (inhibitor of differentiation) gene expression was inversely linked with survival rates, potentially indicating a novel role of EPA and Id3 in the regulation of apoptosis in lipotoxic/cytotoxic conditions. Additionally, signalling studies indicated the combination of lipo- and cyto-toxic effects on the muscle cells acted through ceramide, JNK and MAPK pathways and blocking these pathways using PD98059 (MEK inhibitor) and Fumonisin B1 (ceramide inhibitor) significantly reduced levels of cell death. These findings highlight novel pathways associated with in vitro models of lipotoxicity (palmitate-mediated) and cytotoxicity (inflammatory cytokine mediated) in the potential targeting of molecular modulators of sarcopenic obesity.
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Affiliation(s)
- Amarjit Saini
- Department of Laboratory Medicine, Clinical Physiology, Karolinska Institutet, and Unit of Clinical Physiology, Karolinska University Hospital, 141 86, Stockholm, Sweden
| | - Adam P Sharples
- Stem Cells, Ageing and Molecular Physiology (SCAMP) Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport & Exercise Sciences, School of Sport and Exercise Sciences, Liverpool John Moores University, Life Science Building, Byrom Street Campus, Liverpool, L3 3AF, UK.
| | - Nasser Al-Shanti
- Neuromuscular and Skeletal Ageing Research Group, Healthcare Science Research Institute, Manchester Metropolitan University, Oxford Road, Manchester, M1 5GD, UK
| | - Claire E Stewart
- Stem Cells, Ageing and Molecular Physiology (SCAMP) Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport & Exercise Sciences, School of Sport and Exercise Sciences, Liverpool John Moores University, Life Science Building, Byrom Street Campus, Liverpool, L3 3AF, UK
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27
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Swiderski K, Martins KJB, Chee A, Trieu J, Naim T, Gehrig SM, Baum DM, Brenmoehl J, Chau L, Koopman R, Gregorevic P, Metzger F, Hoeflich A, Lynch GS. Skeletal muscle-specific overexpression of IGFBP-2 promotes a slower muscle phenotype in healthy but not dystrophic mdx mice and does not affect the dystrophic pathology. Growth Horm IGF Res 2016; 30-31:1-10. [PMID: 27544574 DOI: 10.1016/j.ghir.2016.07.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 06/25/2016] [Accepted: 07/27/2016] [Indexed: 01/14/2023]
Abstract
OBJECTIVE The insulin-like growth factor binding proteins (IGFBPs) are thought to modulate cell size and homeostasis via IGF-I-dependent and -independent pathways. There is a considerable dearth of information regarding the function of IGFBPs in skeletal muscle, particularly their role in the pathophysiology of Duchenne muscular dystrophy (DMD). In this study we tested the hypothesis that intramuscular IGFBP-2 overexpression would ameliorate the pathology in mdx dystrophic mice. DESIGN 4week old male C57Bl/10 and mdx mice received a single intramuscular injection of AAV6-empty or AAV6-IGFBP-2 vector into the tibialis anterior muscle. At 8weeks post-injection the effect of IGFBP-2 overexpression on the structure and function of the injected muscle was assessed. RESULTS AAV6-mediated IGFBP-2 overexpression in the tibialis anterior (TA) muscles of 4-week-old C57BL/10 and mdx mice reduced the mass of injected muscle after 8weeks, inducing a slower muscle phenotype in C57BL/10 but not mdx mice. Analysis of inflammatory and fibrotic gene expression revealed no changes between control and IGFBP-2 injected muscles in dystrophic (mdx) mice. CONCLUSIONS Together these results indicate that the IGFBP-2-induced promotion of a slower muscle phenotype is impaired in muscles of dystrophin-deficient mdx mice, which contributes to the inability of IGFBP-2 to ameliorate the dystrophic pathology. The findings implicate the dystrophin-glycoprotein complex (DGC) in the signaling required for this adaptation.
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Affiliation(s)
- Kristy Swiderski
- Basic and Clinical Myology Laboratory, Department of Physiology, University of Melbourne, VIC 3010, Australia
| | - Karen Janet Bernice Martins
- Basic and Clinical Myology Laboratory, Department of Physiology, University of Melbourne, VIC 3010, Australia
| | - Annabel Chee
- Basic and Clinical Myology Laboratory, Department of Physiology, University of Melbourne, VIC 3010, Australia
| | - Jennifer Trieu
- Basic and Clinical Myology Laboratory, Department of Physiology, University of Melbourne, VIC 3010, Australia
| | - Timur Naim
- Basic and Clinical Myology Laboratory, Department of Physiology, University of Melbourne, VIC 3010, Australia
| | - Stefan Martin Gehrig
- Basic and Clinical Myology Laboratory, Department of Physiology, University of Melbourne, VIC 3010, Australia
| | - Dale Michael Baum
- Basic and Clinical Myology Laboratory, Department of Physiology, University of Melbourne, VIC 3010, Australia
| | - Julia Brenmoehl
- Institute for Genome Biology, Leibniz Institute for Farm Animal Biology (FBN), 18196, Dummerstorf, Germany
| | - Luong Chau
- Institute for Genome Biology, Leibniz Institute for Farm Animal Biology (FBN), 18196, Dummerstorf, Germany
| | - René Koopman
- Basic and Clinical Myology Laboratory, Department of Physiology, University of Melbourne, VIC 3010, Australia
| | - Paul Gregorevic
- Muscle Biology and Therapeutics Laboratory, Baker IDI Heart and Diabetes Institute, Melbourne, VIC 3004, Australia
| | - Friedrich Metzger
- F. Hoffmann-La Roche Ltd., pRED, Pharma Research & Early Development, DTA Neuroscience, 4070, Basel, Switzerland
| | - Andreas Hoeflich
- Institute for Genome Biology, Leibniz Institute for Farm Animal Biology (FBN), 18196, Dummerstorf, Germany
| | - Gordon Stuart Lynch
- Basic and Clinical Myology Laboratory, Department of Physiology, University of Melbourne, VIC 3010, Australia.
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28
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Puchert M, Adams V, Linke A, Engele J. Evidence for the involvement of the CXCL12 system in the adaptation of skeletal muscles to physical exercise. Cell Signal 2016; 28:1205-1215. [DOI: 10.1016/j.cellsig.2016.05.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 05/19/2016] [Accepted: 05/24/2016] [Indexed: 12/23/2022]
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29
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Sharples AP, Stewart CE, Seaborne RA. Does skeletal muscle have an 'epi'-memory? The role of epigenetics in nutritional programming, metabolic disease, aging and exercise. Aging Cell 2016; 15:603-16. [PMID: 27102569 PMCID: PMC4933662 DOI: 10.1111/acel.12486] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/24/2016] [Indexed: 12/17/2022] Open
Abstract
Skeletal muscle mass, quality and adaptability are fundamental in promoting muscle performance, maintaining metabolic function and supporting longevity and healthspan. Skeletal muscle is programmable and can ‘remember’ early‐life metabolic stimuli affecting its function in adult life. In this review, the authors pose the question as to whether skeletal muscle has an ‘epi’‐memory? Following an initial encounter with an environmental stimulus, we discuss the underlying molecular and epigenetic mechanisms enabling skeletal muscle to adapt, should it re‐encounter the stimulus in later life. We also define skeletal muscle memory and outline the scientific literature contributing to this field. Furthermore, we review the evidence for early‐life nutrient stress and low birth weight in animals and human cohort studies, respectively, and discuss the underlying molecular mechanisms culminating in skeletal muscle dysfunction, metabolic disease and loss of skeletal muscle mass across the lifespan. We also summarize and discuss studies that isolate muscle stem cells from different environmental niches in vivo (physically active, diabetic, cachectic, aged) and how they reportedly remember this environment once isolated in vitro. Finally, we will outline the molecular and epigenetic mechanisms underlying skeletal muscle memory and review the epigenetic regulation of exercise‐induced skeletal muscle adaptation, highlighting exercise interventions as suitable models to investigate skeletal muscle memory in humans. We believe that understanding the ‘epi’‐memory of skeletal muscle will enable the next generation of targeted therapies to promote muscle growth and reduce muscle loss to enable healthy aging.
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Affiliation(s)
- Adam P. Sharples
- Stem Cells, Ageing and Molecular Physiology (SCAMP) Research Unit Exercise Metabolism and Adaptation Research Group (EMARG) Research Institute for Sport and Exercise Sciences (RISES) Liverpool John Moores University Liverpool UK
| | - Claire E. Stewart
- Stem Cells, Ageing and Molecular Physiology (SCAMP) Research Unit Exercise Metabolism and Adaptation Research Group (EMARG) Research Institute for Sport and Exercise Sciences (RISES) Liverpool John Moores University Liverpool UK
| | - Robert A. Seaborne
- Stem Cells, Ageing and Molecular Physiology (SCAMP) Research Unit Exercise Metabolism and Adaptation Research Group (EMARG) Research Institute for Sport and Exercise Sciences (RISES) Liverpool John Moores University Liverpool UK
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30
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Girven M, Dugdale HF, Owens DJ, Hughes DC, Stewart CE, Sharples AP. l-glutamine Improves Skeletal Muscle Cell Differentiation and Prevents Myotube Atrophy After Cytokine (TNF-α) Stress Via Reduced p38 MAPK Signal Transduction. J Cell Physiol 2016; 231:2720-32. [PMID: 26991744 DOI: 10.1002/jcp.25380] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 03/15/2016] [Indexed: 02/06/2023]
Abstract
Tumour Necrosis Factor-Alpha (TNF-α) is chronically elevated in conditions where skeletal muscle loss occurs. As l-glutamine can dampen the effects of inflamed environments, we investigated the role of l-glutamine in both differentiating C2C12 myoblasts and existing myotubes in the absence/presence of TNF-α (20 ng · ml(-1) ) ± l-glutamine (20 mM). TNF-α reduced the proportion of cells in G1 phase, as well as biochemical (CK activity) and morphological differentiation (myotube number), with corresponding reductions in transcript expression of: Myogenin, Igf-I, and Igfbp5. Furthermore, when administered to mature myotubes, TNF-α induced myotube loss and atrophy underpinned by reductions in Myogenin, Igf-I, Igfbp2, and glutamine synthetase and parallel increases in Fox03, Cfos, p53, and Bid gene expression. Investigation of signaling activity suggested that Akt and ERK1/2 were unchanged, JNK increased (non-significantly) whereas P38 MAPK substantially and significantly increased in both myoblasts and myotubes in the presence of TNF-α. Importantly, 20 mM l-glutamine reduced p38 MAPK activity in TNF-α conditions back to control levels, with a corresponding rescue of myoblast differentiation and a reversal of atrophy in myotubes. l-glutamine resulted in upregulation of genes associated with growth and survival including; Myogenin, Igf-Ir, Myhc2 & 7, Tnfsfr1b, Adra1d, and restored atrophic gene expression of Fox03 back to baseline in TNF-α conditions. In conclusion, l-glutamine supplementation rescued suppressed muscle cell differentiation and prevented myotube atrophy in an inflamed environment via regulation of p38 MAPK. l-glutamine administration could represent an important therapeutic strategy for reducing muscle loss in catabolic diseases and inflamed ageing. J. Cell. Physiol. 9999: 231: 2720-2732, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Matthew Girven
- Stem Cells, Ageing and Molecular Physiology Research Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences (RISES), Liverpool John Moores University, Liverpool, United Kingdom
| | - Hannah F Dugdale
- Stem Cells, Ageing and Molecular Physiology Research Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences (RISES), Liverpool John Moores University, Liverpool, United Kingdom
| | - Daniel J Owens
- Stem Cells, Ageing and Molecular Physiology Research Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences (RISES), Liverpool John Moores University, Liverpool, United Kingdom.,Sorbonne Universités, UPMC University of Paris 06, INSERM UMRS974, CNRS FRE3617, Centre de Recherche en Myologie (CRM), GH Pitié Salpêtrière, Paris 13, France
| | - David C Hughes
- Stem Cells, Ageing and Molecular Physiology Research Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences (RISES), Liverpool John Moores University, Liverpool, United Kingdom.,Department of Neurobiology, Physiology and Behavior, University of California Davis, Davis, California
| | - Claire E Stewart
- Stem Cells, Ageing and Molecular Physiology Research Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences (RISES), Liverpool John Moores University, Liverpool, United Kingdom
| | - Adam P Sharples
- Stem Cells, Ageing and Molecular Physiology Research Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences (RISES), Liverpool John Moores University, Liverpool, United Kingdom
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31
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Passey SL, Bozinovski S, Vlahos R, Anderson GP, Hansen MJ. Serum Amyloid A Induces Toll-Like Receptor 2-Dependent Inflammatory Cytokine Expression and Atrophy in C2C12 Skeletal Muscle Myotubes. PLoS One 2016; 11:e0146882. [PMID: 26784349 PMCID: PMC4718684 DOI: 10.1371/journal.pone.0146882] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 12/24/2015] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Skeletal muscle wasting is an important comorbidity of Chronic Obstructive Pulmonary Disease (COPD) and is strongly correlated with morbidity and mortality. Patients who experience frequent acute exacerbations of COPD (AECOPD) have more severe muscle wasting and reduced recovery of muscle mass and function after each exacerbation. Serum levels of the pro-inflammatory acute phase protein Serum Amyloid A (SAA) can rise more than 1000-fold in AECOPD and are predictively correlated with exacerbation severity. The direct effects of SAA on skeletal muscle are poorly understood. Here we have examined SAA effects on pro-inflammatory cachectic cytokine expression (IL-6 and TNFα) and atrophy in C2C12 myotubes. RESULTS SAA increased IL-6 (31-fold) and TNFα (6.5-fold) mRNA levels compared to control untreated cells after 3h of SAA treatment, and increased secreted IL-6 protein at 24h. OxPAPC, a dual TLR2 and TLR4 inhibitor, reduced the response to SAA by approximately 84% compared to SAA alone, and the TLR2 neutralising antibody T2.5 abolished SAA-induced expression of IL-6, indicating that SAA signalling in C2C12 myotubes is primarily via TLR2. SAA also reduced myotube width by 10-13% and induced a 2.5-fold increase in the expression of the muscle atrophy gene Atrogin-1, suggesting direct effects of SAA on muscle wasting. Blocking of TLR2 inhibited the SAA-induced decrease in myotube width and Atrogin-1 gene expression, indicating that SAA induces atrophy through TLR2. CONCLUSIONS These data demonstrate that SAA stimulates a robust pro-inflammatory response in skeletal muscle myotubes via the TLR2-dependent release of IL-6 and TNFα. Furthermore, the observed atrophy effects indicate that SAA could also be directly contributing to the wasting and poor recovery of muscle mass. Therapeutic strategies targeting this SAA-TLR2 axis may therefore ameliorate muscle wasting in AECOPD and a range of other inflammatory conditions associated with loss of muscle mass.
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Affiliation(s)
- Samantha L. Passey
- Lung Health Research Centre, Department of Pharmacology and Therapeutics, University of Melbourne, Parkville, Melbourne, Victoria, Australia
- School of Health and Biomedical Sciences, RMIT University, Bundoora, Melbourne, Victoria, Australia
| | - Steven Bozinovski
- Lung Health Research Centre, Department of Pharmacology and Therapeutics, University of Melbourne, Parkville, Melbourne, Victoria, Australia
- School of Health and Biomedical Sciences, RMIT University, Bundoora, Melbourne, Victoria, Australia
| | - Ross Vlahos
- Lung Health Research Centre, Department of Pharmacology and Therapeutics, University of Melbourne, Parkville, Melbourne, Victoria, Australia
- School of Health and Biomedical Sciences, RMIT University, Bundoora, Melbourne, Victoria, Australia
| | - Gary P. Anderson
- Lung Health Research Centre, Department of Pharmacology and Therapeutics, University of Melbourne, Parkville, Melbourne, Victoria, Australia
| | - Michelle J. Hansen
- Lung Health Research Centre, Department of Pharmacology and Therapeutics, University of Melbourne, Parkville, Melbourne, Victoria, Australia
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Testosterone enables growth and hypertrophy in fusion impaired myoblasts that display myotube atrophy: deciphering the role of androgen and IGF-I receptors. Biogerontology 2015; 17:619-39. [PMID: 26538344 PMCID: PMC4889645 DOI: 10.1007/s10522-015-9621-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 10/19/2015] [Indexed: 11/09/2022]
Abstract
We have previously highlighted the ability of testosterone (T) to improve differentiation and myotube hypertrophy in fusion impaired myoblasts that display reduced myotube hypertrophy via multiple population doublings (PD) versus their parental controls (CON); an observation which is abrogated via PI3K/Akt inhibition (Deane et al. 2013). However, whether the most predominant molecular mechanism responsible for T induced hypertrophy occurs directly via androgen receptor or indirectly via IGF-IR/PI3K/Akt pathway is currently debated. PD and CON C2C12 muscle cells were exposed to low serum conditions in the presence or absence of T (100 nM) ± inhibitors of AR (flutamide/F, 40 μm) and IGF-IR (picropodophyllin/PPP, 150 nM) for 72 h and 7 days (early/late muscle differentiation respectively). T increased AR and Akt abundance, myogenin gene expression, and myotube hypertrophy, but not ERK1/2 activity in both CON and PD cell types. Akt activity was not increased significantly in either cell type with T. Testosterone was also unable to promote early differentiation in the presence of IGF-IR inhibitor (PPP) yet still able to promote appropriate later increases in myotube hypertrophy and AR abundance despite IGF-IR inhibition. The addition of the AR inhibitor powerfully attenuated all T induced increases in differentiation and myotube hypertrophy with corresponding reductions in AR abundance, phosphorylated Akt, ERK1/2 and gene expression of IGF-IR, myoD and myogenin with increases in myostatin mRNA in both cell types. Interestingly, despite basally reduced differentiation and myotube hypertrophy, PD cells showed larger T induced increases in AR abundance vs. CON cells, a response abrogated in the presence of AR but not IGF-IR inhibitors. Furthermore, T induced increases in Akt abundance were sustained despite the presence of IGF-IR inhibition in PD cells only. Importantly, flutamide alone reduced IGF-IR mRNA in both cell types across time points, with an observed reduction in activity of ERK and Akt, suggesting that IGF-IR was transcriptionally regulated by AR. However, where testosterone increased AR protein content there was no increases observed in IGF-IR gene expression. This suggested that sufficient AR was important to enable normal IGF-IR expression and downstream signalling, yet elevated levels of AR due to testosterone had no further effect on IGF-IR mRNA, despite testosterone increasing Akt abundance in the presence of IGF-IR inhibitor. In conclusion, testosterones ability to improve differentiation and myotube hypertrophy occurred predominately via increases in AR and Akt abundance in both CON and PD cells, with fusion impaired cells (PD) showing an increased responsiveness to T induced AR levels. Finally, T induced increases in myotube hypertrophy (but not early differentiation) occurred independently of upstream IGF-IR input, however it was apparent that normal AR function in basal conditions was required for adequate IGF-IR gene expression and downstream ERK/Akt activity.
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Nozaki T, Nikai S, Okabe R, Nagahama K, Eto N. A novel in vitro model of sarcopenia using BubR1 hypomorphic C2C12 myoblasts. Cytotechnology 2015; 68:1705-15. [PMID: 26464273 DOI: 10.1007/s10616-015-9920-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 10/01/2015] [Indexed: 12/23/2022] Open
Abstract
Sarcopenia is the age-related loss of skeletal muscle mass and function with adverse outcomes that include physical disability, poor quality of life, and death. The detailed molecular mechanisms remain unknown. An in vitro muscle atrophy model is needed to enable mechanistic studies. To create such a model, we employed BubR1 insufficiency which causes premature ageing in mice. Using C2C12 cells, a recognized in vitro model of the skeletal muscle cell, we obtained the BubR1 hypomorphic C2C12 (C2C12BKD) cells by using shRNA. The resulting C2C12BKD cells displayed several characteristics of the sarcopenic muscle cell. In C2C12BKD cells, formation of myotubes, assessed by analysis of fusion index, was markedly reduced as was the expression of myogenin and MyoD, two marker genes for myogenesis. Moreover, the cells showed increased expression of the muscle-specific ubiquitin ligases Atrogin-1 and MuRF-1, indicating increased protein degradation through the ubiquitin-proteasome dependent proteolytic pathway. These results suggest that C2C12BKD cells are potentially useful as a novel in vitro model of sarcopenia.
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Affiliation(s)
- Takateru Nozaki
- Department of Biochemistry and Applied Biosciences, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki, 889-2192, Japan
| | - Shiori Nikai
- Department of Biochemistry and Applied Biosciences, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki, 889-2192, Japan
| | - Ryo Okabe
- Department of Biochemistry and Applied Biosciences, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki, 889-2192, Japan
| | - Kiyoko Nagahama
- Interdisciplinary Graduate School of Agriculture and Engineering, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki, 889-2192, Japan
| | - Nozomu Eto
- Department of Biochemistry and Applied Biosciences, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki, 889-2192, Japan.
- Interdisciplinary Graduate School of Agriculture and Engineering, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki, 889-2192, Japan.
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Huang PL, Hou MS, Wang SW, Chang CL, Liou YH, Liao NS. Skeletal muscle interleukin 15 promotes CD8(+) T-cell function and autoimmune myositis. Skelet Muscle 2015; 5:33. [PMID: 26417430 PMCID: PMC4584479 DOI: 10.1186/s13395-015-0058-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 09/08/2015] [Indexed: 12/30/2022] Open
Abstract
Background Interleukin 15 (IL-15) is thought to be abundant in the skeletal muscle under steady state conditions based on RNA expression; however, the IL-15 RNA level may not reflect the protein level due to post-transcriptional regulation. Although exogenous protein treatment and overexpression studies indicated IL-15 functions in the skeletal muscle, how the skeletal muscle cell uses IL-15 remains unclear. In myositis patients, IL-15 protein is up-regulated in the skeletal muscle. Given the supporting role of IL-15 in CD8+ T-cell survival and activation and the pathogenic role of cytotoxic CD8+ T cells in polymyositis and inclusion-body myositis, we hypothesize that IL-15 produced by the inflamed skeletal muscle promotes myositis via CD8+ T cells. Methods Expression of IL-15 and IL-15 receptors at the protein level by skeletal muscle cells were examined under steady state and cytokine stimulation conditions. The functions of IL-15 in the skeletal muscle were investigated using Il15 knockout (Il15−/−) mice. The immune regulatory role of skeletal muscle IL-15 was determined by co-culturing cytokine-stimulated muscle cells and memory-like CD8+ T cells in vitro and by inducing autoimmune myositis in skeletal-muscle-specific Il15−/− mice. Results We found that the IL-15 protein was not expressed by skeletal muscle cells under steady state condition but induced by tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ) stimulation and expressed as IL-15/IL-15 receptor alpha (IL-15Rα) complex. Skeletal muscle cells expressed a scanty amount of IL-15 receptor beta (IL-15Rβ) under either conditions and only responded to a high concentration of IL-15 hyperagonist, but not IL-15. Consistently, deficiency of endogenous IL-15 affected neither skeletal muscle growth nor its responses to TNF-α and IFN-γ. On the other hand, the cytokine-stimulated skeletal muscle cells presented antigen and provided IL-15 to promote the effector function of memory-like CD8+ T cells. Genetic ablation of Il15 in skeletal muscle cells greatly ameliorated autoimmune myositis in mice. Conclusions These findings together indicate that skeletal muscle IL-15 directly regulates immune effector cells but not muscle cells and thus presents a potential therapeutic target for myositis. Electronic supplementary material The online version of this article (doi:10.1186/s13395-015-0058-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Po-Lin Huang
- Molecular Cell Biology, Taiwan International Graduate Program, Institute of Molecular Biology, Academia Sinica, and Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan ; Institute of Molecular Biology, Academia Sinica, Taipei, 11529 Taiwan
| | - Mau-Sheng Hou
- Institute of Molecular Biology, Academia Sinica, Taipei, 11529 Taiwan
| | - Szu-Wen Wang
- Institute of Molecular Biology, Academia Sinica, Taipei, 11529 Taiwan
| | - Chin-Ling Chang
- Institute of Molecular Biology, Academia Sinica, Taipei, 11529 Taiwan
| | - Yae-Huei Liou
- Institute of Molecular Biology, Academia Sinica, Taipei, 11529 Taiwan
| | - Nan-Shih Liao
- Molecular Cell Biology, Taiwan International Graduate Program, Institute of Molecular Biology, Academia Sinica, and Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan ; Institute of Molecular Biology, Academia Sinica, Taipei, 11529 Taiwan
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Sharples AP, Polydorou I, Hughes DC, Owens DJ, Hughes TM, Stewart CE. Skeletal muscle cells possess a 'memory' of acute early life TNF-α exposure: role of epigenetic adaptation. Biogerontology 2015; 17:603-17. [PMID: 26349924 DOI: 10.1007/s10522-015-9604-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 08/27/2015] [Indexed: 12/20/2022]
Abstract
Sufficient quantity and quality of skeletal muscle is required to maintain lifespan and healthspan into older age. The concept of skeletal muscle programming/memory has been suggested to contribute to accelerated muscle decline in the elderly in association with early life stress such as fetal malnutrition. Further, muscle cells in vitro appear to remember the in vivo environments from which they are derived (e.g. cancer, obesity, type II diabetes, physical inactivity and nutrient restriction). Tumour-necrosis factor alpha (TNF-α) is a pleiotropic cytokine that is chronically elevated in sarcopenia and cancer cachexia. Higher TNF-α levels are strongly correlated with muscle loss, reduced strength and therefore morbidity and earlier mortality. We have extensively shown that TNF-α impairs regenerative capacity in mouse and human muscle derived stem cells [Meadows et al. (J Cell Physiol 183(3):330-337, 2000); Foulstone et al. (J Cell Physiol 189(2):207-215, 2001); Foulstone et al. (Exp Cell Res 294(1):223-235, 2004); Stewart et al. (J Cell Physiol 198(2):237-247, 2004); Al-Shanti et al. (Growth factors (Chur, Switzerland) 26(2):61-73, 2008); Saini et al. (Growth factors (Chur, Switzerland) 26(5):239-253, 2008); Sharples et al. (J Cell Physiol 225(1):240-250, 2010)]. We have also recently established an epigenetically mediated mechanism (SIRT1-histone deacetylase) regulating survival of myoblasts in the presence of TNF-α [Saini et al. (Exp Physiol 97(3):400-418, 2012)]. We therefore wished to extend this work in relation to muscle memory of catabolic stimuli and the potential underlying epigenetic modulation of muscle loss. To enable this aim; C2C12 myoblasts were cultured in the absence or presence of early TNF-α (early proliferative lifespan) followed by 30 population doublings in the absence of TNF-α, prior to the induction of differentiation in low serum media (LSM) in the absence or presence of late TNF-α (late proliferative lifespan). The cells that received an early plus late lifespan dose of TNF-α exhibited reduced morphological (myotube number) and biochemical (creatine kinase activity) differentiation vs. control cells that underwent the same number of proliferative divisions but only a later life encounter with TNF-α. This suggested that muscle cells had a morphological memory of the acute early lifespan TNF-α encounter. Importantly, methylation of myoD CpG islands were increased in the early TNF-α cells, 30 population doublings later, suggesting that even after an acute encounter with TNF-α, the cells have the capability of retaining elevated methylation for at least 30 cellular divisions. Despite these fascinating findings, there were no further increases in myoD methylation or changes in its gene expression when these cells were exposed to a later TNF-α dose suggesting that this was not directly responsible for the decline in differentiation observed. In conclusion, data suggest that elevated myoD methylation is retained throughout muscle cells proliferative lifespan as result of early life TNF-α treatment and has implications for the epigenetic control of muscle loss.
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Affiliation(s)
- Adam P Sharples
- Stem Cells, Ageing and Molecular Physiology Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences (RISES), School of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK.
| | - Ioanna Polydorou
- Department of Neuropediatrics and NeuroCure Clinical Research Center, Charité-Universitätsmedizin Berlin, Berlin, Germany.,UFR des Sciences de la Santé, Université de Versailles Saint-Quentin-en-Yvelines, Montigny-Le-Bretonneux, France
| | - David C Hughes
- Stem Cells, Ageing and Molecular Physiology Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences (RISES), School of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK.,Department of Neurobiology, Physiology and Behavior, University of California, Davis, CA, USA
| | - Daniel J Owens
- Stem Cells, Ageing and Molecular Physiology Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences (RISES), School of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - Thomas M Hughes
- Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan, Ghent, Belgium.,Instituto de Física y Astronomía, Universidad de Valparaíso, Valparaiso, Chile
| | - Claire E Stewart
- Stem Cells, Ageing and Molecular Physiology Unit, Exercise Metabolism and Adaptation Research Group, Research Institute for Sport and Exercise Sciences (RISES), School of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
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A novel adipokine C1q/TNF-related protein 3 is expressed in developing skeletal muscle and controls myoblast proliferation and differentiation. Mol Cell Biochem 2015; 409:271-82. [DOI: 10.1007/s11010-015-2531-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 08/06/2015] [Indexed: 01/08/2023]
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Sharples AP, Hughes DC, Deane CS, Saini A, Selman C, Stewart CE. Longevity and skeletal muscle mass: the role of IGF signalling, the sirtuins, dietary restriction and protein intake. Aging Cell 2015; 14:511-23. [PMID: 25866088 PMCID: PMC4531066 DOI: 10.1111/acel.12342] [Citation(s) in RCA: 145] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/03/2015] [Indexed: 12/11/2022] Open
Abstract
Advancing age is associated with a progressive loss of skeletal muscle (SkM) mass and function. Given the worldwide aging demographics, this is a major contributor to morbidity, escalating socio-economic costs and ultimately mortality. Previously, it has been established that a decrease in regenerative capacity in addition to SkM loss with age coincides with suppression of insulin/insulin-like growth factor signalling pathways. However, genetic or pharmacological modulations of these highly conserved pathways have been observed to significantly enhance life and healthspan in various species, including mammals. This therefore provides a controversial paradigm in which reduced regenerative capacity of skeletal muscle tissue with age potentially promotes longevity of the organism. This paradox will be assessed and considered in the light of the following: (i) the genetic knockout, overexpression and pharmacological models that induce lifespan extension (e.g. IRS-1/s6K KO, mTOR inhibition) versus the important role of these signalling pathways in SkM growth and adaptation; (ii) the role of the sirtuins (SIRTs) in longevity versus their emerging role in SkM regeneration and survival under catabolic stress; (iii) the role of dietary restriction and its impact on longevity versus skeletal muscle mass regulation; (iv) the crosstalk between cellular energy metabolism (AMPK/TSC2/SIRT1) and survival (FOXO) versus growth and repair of SkM (e.g. AMPK vs. mTOR); and (v) the impact of protein feeding in combination with dietary restriction will be discussed as a potential intervention to maintain SkM mass while increasing longevity and enabling healthy aging.
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Affiliation(s)
- Adam P. Sharples
- Stem Cells, Ageing & Molecular Physiology Unit; Research Institute for Sport and Exercise Sciences (RISES); Exercise Metabolism and Adaptation Research Group (EMARG); Liverpool John Moores University; Tom Reilly Building Liverpool L3 3AF UK
| | - David C. Hughes
- Stem Cells, Ageing & Molecular Physiology Unit; Research Institute for Sport and Exercise Sciences (RISES); Exercise Metabolism and Adaptation Research Group (EMARG); Liverpool John Moores University; Tom Reilly Building Liverpool L3 3AF UK
- Department of Neurobiology, Physiology and Behavior; University of California; Davis California CA 95616 USA
| | - Colleen S. Deane
- MRC/ARUK Centre of Excellence for Musculoskeletal Ageing Research; School of Medicine; University of Nottingham; Royal Derby Hospital; Derby DE22 3DT UK
- School of Health and Social Care; Bournemouth University; Bournemouth BH12 5BB UK
| | - Amarjit Saini
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm 171 77 Sweden
| | - Colin Selman
- Glasgow Ageing Research Network (GARNER); Institute of Biodiversity, Animal Health and Comparative Medicine; College of Medicine, Veterinary and Life Sciences; University of Glasgow; Glasgow G12 8QQ UK
| | - Claire E. Stewart
- Stem Cells, Ageing & Molecular Physiology Unit; Research Institute for Sport and Exercise Sciences (RISES); Exercise Metabolism and Adaptation Research Group (EMARG); Liverpool John Moores University; Tom Reilly Building Liverpool L3 3AF UK
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Deshmukh AS, Murgia M, Nagaraj N, Treebak JT, Cox J, Mann M. Deep proteomics of mouse skeletal muscle enables quantitation of protein isoforms, metabolic pathways, and transcription factors. Mol Cell Proteomics 2015; 14:841-53. [PMID: 25616865 PMCID: PMC4390264 DOI: 10.1074/mcp.m114.044222] [Citation(s) in RCA: 203] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Indexed: 11/07/2022] Open
Abstract
Skeletal muscle constitutes 40% of individual body mass and plays vital roles in locomotion and whole-body metabolism. Proteomics of skeletal muscle is challenging because of highly abundant contractile proteins that interfere with detection of regulatory proteins. Using a state-of-the art MS workflow and a strategy to map identifications from the C2C12 cell line model to tissues, we identified a total of 10,218 proteins, including skeletal muscle specific transcription factors like myod1 and myogenin and circadian clock proteins. We obtain absolute abundances for proteins expressed in a muscle cell line and skeletal muscle, which should serve as a valuable resource. Quantitation of protein isoforms of glucose uptake signaling pathways and in glucose and lipid metabolic pathways provides a detailed metabolic map of the cell line compared with tissue. This revealed unexpectedly complex regulation of AMP-activated protein kinase and insulin signaling in muscle tissue at the level of enzyme isoforms.
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Affiliation(s)
- Atul S Deshmukh
- From the ‡Department of Proteomics and Signal Transduction, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
| | - Marta Murgia
- From the ‡Department of Proteomics and Signal Transduction, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany; §Department of Biomedical Sciences, University of Padova, Viale G. Colombo 3, 35121 Padua, Italy
| | - Nagarjuna Nagaraj
- From the ‡Department of Proteomics and Signal Transduction, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
| | - Jonas T Treebak
- ¶The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Integrative Physiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jürgen Cox
- From the ‡Department of Proteomics and Signal Transduction, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
| | - Matthias Mann
- From the ‡Department of Proteomics and Signal Transduction, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany; ‖The Novo Nordisk Foundation Center for Protein Research, Department for proteomics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Acute mechanical overload increases IGF-I and MMP-9 mRNA in 3D tissue-engineered skeletal muscle. Biotechnol Lett 2014; 36:1113-24. [PMID: 24563297 DOI: 10.1007/s10529-014-1464-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 01/09/2014] [Indexed: 01/24/2023]
Abstract
Skeletal muscle (SkM) is a tissue that responds to mechanical load following both physiological (exercise) or pathophysiological (bed rest) conditions. The heterogeneity of human samples and the experimental and ethical limitations of animal studies provide a rationale for the study of SkM plasticity in vitro. Many current in vitro approaches of mechanical loading of SkM disregard the three-dimensional (3D) structure in vivo. Tissue engineered 3D SkM, that displays highly aligned and differentiated myotubes, was used to investigate mechano-regulated gene transcription of genes implicated in hypertrophy/atrophy. Static loading (STL) and ramp loading (RPL) at 10 % strain for 60 min were used as mechano-stimulation with constructs sampled immediately for RNA extraction. STL increased IGF-I mRNA compared to both RPL and CON (control, p = 0.003 and 0.011 respectively) whilst MMP-9 mRNA increased in STL and RPL compared to CON (both p < 0.05). IGFBP-2 mRNA was differentially regulated in RPL and STL compared to CON (p = 0.057), whilst a reduction in IGFBP-5 mRNA was found for STL and RPL compared to CON (both p < 0.05). There was no effect in the expression of putative atrophic genes, myostatin, MuRF-1 and MAFBx (all p > 0.05). These data demonstrate a transcriptional signature associated with SkM hypertrophy within a tissue-engineered model that more greatly recapitulates the in vivo SkM structure compared previously published studies.
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Montesano A, Luzi L, Senesi P, Mazzocchi N, Terruzzi I. Resveratrol promotes myogenesis and hypertrophy in murine myoblasts. J Transl Med 2013; 11:310. [PMID: 24330398 PMCID: PMC3867424 DOI: 10.1186/1479-5876-11-310] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 12/05/2013] [Indexed: 12/30/2022] Open
Abstract
Background Nutrigenomics elucidate the ability of bioactive food components to influence gene expression, protein synthesis, degradation and post-translational modifications. Resveratrol (RSV), natural polyphenol found in grapes and in other fruits, has a plethora of health benefits in a variety of human diseases: cardio- and neuroprotection, immune regulation, cancer chemoprevention, DNA repair, prevention of mitochondrial disorder, avoidance of obesity-related diseases. In skeletal muscle, RSV acts on protein catabolism and muscle function, conferring resistance against oxidative stress, injury and cell death, but its action mechanisms and protein targets in myogenesis process are not completely known. Myogenesis is a dynamic multistep process regulated by Myogenic Regulator Factors (MRFs), responsible of the commitment of myogenic cell into skeletal muscle: mononucleated undifferentiated myoblasts break free from cell cycle, elongate and fuse to form multinucleated myotubes. Skeletal muscle hypertrophy can be defined as a result of an increase in the size of pre-existing skeletal muscle fibers accompanied by increased protein synthesis, mainly regulated by Insulin Like Growth Factor 1 (IGF-1), PI3-K/AKT signaling pathways. Aim of this work was the study of RSV effects on proliferation, differentiation process and hypertrophy in C2C12 murine cells. Methods To study proliferative phase, cells were incubated in growth medium with/without RSV (0.1 or 25 μM) until reaching sub confluence condition (24, 48, 72 h). To examine differentiation, at 70% confluence, cells were transferred in differentiation medium both with/without RSV (0.1 or 25 μM) for 24, 48, 72, 96 hours. After 72 hours of differentiation, the genesis of hypertrophy in neo-formed myotubes was analyzed. Results Data showed that RSV regulates cell cycle exit and induces C2C12 muscle differentiation. Furthermore, RSV might control MRFs and muscle-specific proteins synthesis. In late differentiation, RSV has positive effects on hypertrophy: RSV stimulates IGF-1 signaling pathway, in particular AKT and ERK 1/2 protein activation, AMPK protein level and induces hypertrophic morphological changes in neo-formed myotubes modulating cytoskeletal proteins expression. Conclusions RSV might control cell cycle promoting myogenesis and hypertrophy in vitro, opening a novel field of application of RSV in clinical conditions characterized by chronic functional and morphological muscle impairment.
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Affiliation(s)
| | | | | | | | - Ileana Terruzzi
- Division of Metabolic and Cardiovascular Sciences, Metabolism, Nutrigenomics and Cellular Differentiation Unit, DIBIT-San Raffaele Scientific Institute, Milan, Italy.
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Cheng CS, El-Abd Y, Bui K, Hyun YE, Hughes RH, Kraus WE, Truskey GA. Conditions that promote primary human skeletal myoblast culture and muscle differentiation in vitro. Am J Physiol Cell Physiol 2013; 306:C385-95. [PMID: 24336652 DOI: 10.1152/ajpcell.00179.2013] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Conditions under which skeletal myoblasts are cultured in vitro are critical to growth and differentiation of these cells into mature skeletal myofibers. We examined several culture conditions that promoted human skeletal myoblast (HSkM) culture and examined the effect of microRNAs and mechanical stimulation on differentiation. Culture conditions for HSkM are different from those that enable rapid C2C12 myoblast differentiation. Culture on a growth factor-reduced Matrigel (GFR-MG)-coated surface in 2% equine serum-supplemented differentiation medium to promote HSkM differentiation under static conditions was compared with culture conditions used for C2C12 cell differentiation. Such conditions led to a >20-fold increase in myogenic miR-1, miR-133a, and miR-206 expression, a >2-fold increase in myogenic transcription factor Mef-2C expression, and an increase in sarcomeric α-actinin protein. Imposing ±10% cyclic stretch at 0.5 Hz for 1 h followed by 5 h of rest over 2 wk produced a >20% increase in miR-1, miR-133a, and miR-206 expression in 8% equine serum and a >35% decrease in 2% equine serum relative to static conditions. HSkM differentiation was accelerated in vitro by inhibition of proliferation-promoting miR-133a: immunofluorescence for sarcomeric α-actinin exhibited accelerated development of striations compared with the corresponding negative control, and Western blotting showed 30% more α-actinin at day 6 postdifferentiation. This study showed that 100 μg/ml GFR-MG coating and 2% equine serum-supplemented differentiation medium enhanced HSkM differentiation and myogenic miR expression and that addition of antisense miR-133a alone can accelerate primary human skeletal muscle differentiation in vitro.
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Affiliation(s)
- Cindy S Cheng
- Department of Biomedical Engineering, Duke University, Durham, North Carolina; and
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Deane CS, Hughes DC, Sculthorpe N, Lewis MP, Stewart CE, Sharples AP. Impaired hypertrophy in myoblasts is improved with testosterone administration. J Steroid Biochem Mol Biol 2013; 138:152-61. [PMID: 23714396 DOI: 10.1016/j.jsbmb.2013.05.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 05/08/2013] [Accepted: 05/14/2013] [Indexed: 11/24/2022]
Abstract
We investigated the ability of testosterone (T) to restore differentiation in multiple population doubled (PD) murine myoblasts, previously shown to have a reduced differentiation in monolayer and bioengineered skeletal muscle cultures vs. their parental controls (CON) (Sharples et al., 2011, 2012 [7,26]). Cells were exposed to low serum conditions in the presence or absence of T (100nM)±PI3K inhibitor (LY294002) for 72h and 7 days (early and late muscle differentiation respectively). Morphological analyses were performed to determine myotube number, diameter (μm) and myonuclear accretion as indices of differentiation and myotube hypertrophy. Changes in gene expression for myogenin, mTOR and myostatin were also performed. Myotube diameter in CON and PD cells increased from 17.32±2.56μm to 21.02±1.89μm and 14.58±2.66μm to 18.29±3.08μm (P≤0.05) respectively after 72h of T exposure. The increase was comparable in both PD (+25%) and CON cells (+21%) suggesting a similar intrinsic ability to respond to exogenous T administration. T treatment also significantly increased myonuclear accretion (% of myotubes expressing 5+ nuclei) in both cell types after 7 days exposure (P≤0.05). Addition of PI3K inhibitor (LY294002) in the presence of T attenuated these effects in myotube morphology (in both cell types) suggesting a role for the PI3K pathway in T stimulated hypertrophy. Finally, PD myoblasts showed reduced responsiveness to T stimulated mRNA expression of mTOR vs. CON cells and T also reduced myostatin expression in PD myoblasts only. The present study demonstrates testosterone administration improves hypertrophy in myoblasts that basally display impaired differentiation and hypertrophic capacity vs. their parental controls, the action of testosterone in this model was mediated by PI3K/Akt pathway.
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Affiliation(s)
- Colleen S Deane
- Muscle Cellular and Molecular Physiology Research Group (MCMPRG), Institute of Sport and Physical Activity Research (ISPAR), University of Bedfordshire, UK; School of Health and Social Care, Bournemouth University, UK
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Durcan PJ, Al-Shanti N, Stewart CE. Identification and characterization of novel Kirrel isoform during myogenesis. Physiol Rep 2013; 1:e00044. [PMID: 24303129 PMCID: PMC3835000 DOI: 10.1002/phy2.44] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 07/03/2013] [Indexed: 12/31/2022] Open
Abstract
Somatic cell fusion is an essential component of skeletal muscle development and growth and repair from injury. Additional cell types such as trophoblasts and osteoclasts also require somatic cell fusion events to perform their physiological functions. Currently we have rudimentary knowledge on molecular mechanisms regulating somatic cell fusion events in mammals. We therefore investigated during in vitro murine myogenesis a mammalian homolog, Kirrel, of the Drosophila Melanogaster genes Roughest (Rst) and Kin of Irre (Kirre) which regulate somatic muscle cell fusion during embryonic development. Our results demonstrate the presence of a novel murine Kirrel isoform containing a truncated cytoplasmic domain which we term Kirrel B. Protein expression levels of Kirrel B are inverse to the occurrence of cell fusion events during in vitro myogenesis which is in stark contrast to the expression profile of Rst and Kirre during myogenesis in Drosophila. Furthermore, chemical inhibition of cell fusion confirmed the inverse expression pattern of Kirrel B protein levels in relation to cell fusion events. The discovery of a novel Kirrel B protein isoform during myogenesis highlights the need for more thorough investigation of the similarities and potential differences between fly and mammals with regards to the muscle cell fusion process.
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Affiliation(s)
- Peter J Durcan
- Department of Physiological Sciences, Stellenbosch University Merriman avenue, Stellenbosch, 7600, Western Cape, South Africa ; Institute for Biomedical Research into Human movement, School of Healthcare Science, Manchester Metropolitan University Oxford road, M1 5GD, Manchester, U.K
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Sharples AP, Al-Shanti N, Hughes DC, Lewis MP, Stewart CE. The role of insulin-like-growth factor binding protein 2 (IGFBP2) and phosphatase and tensin homologue (PTEN) in the regulation of myoblast differentiation and hypertrophy. Growth Horm IGF Res 2013; 23:53-61. [PMID: 23583027 DOI: 10.1016/j.ghir.2013.03.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 01/30/2013] [Accepted: 03/13/2013] [Indexed: 11/22/2022]
Abstract
The complex actions of the insulin-like-growth factor binding proteins (IGFBPs) in skeletal muscle are becoming apparent, with IGFBP2 being implicated in skeletal muscle cell proliferation and differentiation (Ernst et al., 1992; Sharples et al., 2010). Furthermore, PTEN signalling has been linked to IGFBP2 action in other cell types by co-ordinating downstream Akt signalling, a known modulator of myoblast differentiation. The present study therefore aimed to determine the interaction between IGFBP2 and PTEN on myoblast differentiation. It has previously been established that C2C12 cells have high IGFBP2 gene expression upon transfer to low serum media, and that expression reduces rapidly as cells differentiate over 72 h [1]. Wishing to establish a potential role for IGFBP2 in this model, a neutralising IGFBP2 antibody was administered to C2C12 myoblasts upon initiation of differentiation. Myoblasts subsequently displayed reduced morphological differentiation (myotube number), biochemical differentiation (creatine kinase) and myotube hypertrophy (myotube area) with an early reduction in Akt phosphorylation. Knock-down of phosphatase and tensin homologue (PTEN) using siRNA in the absence of the neutralising antibody did not improve differentiation or hypertrophy vs. control conditions, however, in the presence of the neutralising IGFBP2 antibody, differentiation was restored and importantly hypertrophy exceeded that of control levels. Overall, these data suggest that; 1) reduced early availability of IGFBP2 can inhibit myoblast differentiation at later time points, 2) knock-down of PTEN levels can restore myoblast differentiation in the presence of neutralising IGFBP2 antibody, and 3) PTEN inhibition acts as a potent inducer of myotube hypertrophy when the availability of IGFBP2 is reduced in C2C12 myoblasts.
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Affiliation(s)
- Adam P Sharples
- Stem Cell, Ageing and Molecular Physiology (SCAMP) Unit, Research Institute for Sport and Exercise Sciences (RISES), School of Sport and Exercise Sciences, Liverpool John Moores University, Tom Reilly Building, Byrom Street, Liverpool, UK.
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Rao N, Evans S, Stewart D, Spencer KH, Sheikh F, Hui EE, Christman KL. Fibroblasts influence muscle progenitor differentiation and alignment in contact independent and dependent manners in organized co-culture devices. Biomed Microdevices 2013; 15:161-9. [PMID: 22983793 PMCID: PMC3537877 DOI: 10.1007/s10544-012-9709-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Myoblasts are precursor muscle cells that lie nascent to mature skeletal muscle. Once muscle is damaged, these cells migrate, fuse, and regenerate the muscle tissue. It is known that skeletal muscle can partially regenerate in vivo after muscle tissue damage. However, this regeneration does not always occur, especially in more severe injuries. Cellular therapy using tissue-engineering approaches has been shown to improve organ repair and function. To exploit potential benefits of using cell therapy as an avenue for skeletal muscle repair, it is important to understand the cellular dynamics underlying skeletal myocyte formation and growth. Cardiac fibroblasts have been shown to have a major influence on cardiomyocyte function, repair, and overall spatial distribution. However, little is known regarding fibroblasts' role on skeletal myocyte function. In this study, we utilized a reconfigurable co-culture device to understand the contact and paracrine effects of fibroblasts on skeletal myocyte alignment and differentiation using murine myoblast and fibroblast cell lines. We demonstrate that myotube alignment is increased by direct contact with fibroblasts, while myotube differentiation is reduced both in the gap and contact configurations with fibroblasts after 6 days of co-culture. Furthermore, neutralizing antibodies to FGF-2 can block these effects of fibroblasts on myotube differentiation and alignment. Finally, bi-directional signaling is critical to the observed myoblast-fibroblast interactions, since conditioned media could not reproduce the same effects observed in the gap configuration. These findings could have direct implications on cell therapies for repairing skeletal muscle, which have only utilized skeletal myoblasts or stem cell populations alone.
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Affiliation(s)
- Nikhil Rao
- Department of Bioengineering, University of California, San Diego. 2880 Torrey Pines Scenic Drive, La Jolla, CA 92037, USA
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Sharples AP, Player DJ, Martin NRW, Mudera V, Stewart CE, Lewis MP. Modelling in vivo skeletal muscle ageing in vitro using three-dimensional bioengineered constructs. Aging Cell 2012; 11:986-95. [PMID: 22882433 DOI: 10.1111/j.1474-9726.2012.00869.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Degeneration of skeletal muscle (SkM) with age (sarcopenia) is a major contributor to functional decline, morbidity and mortality. Methodological implications often make it difficult to embark on interventions in already frail and diseased elderly individuals. Using in vitro three-dimensional (3D) bioengineered skeletal muscle constructs that model aged phenotypes and incorporate a representative extracellular matrix (collagen), are under tension, and display morphological and transcript expression of mature skeletal muscle may more accurately characterize the SkM niche. Furthermore, an in vitro model would provide greater experimental manipulation with regard to gene, pharmacological and exercise (mechanical stretch/electrical stimulation) therapies and thus strategies for combating muscle wasting with age. The present study utilized multiple population-doubled (MPD) murine myoblasts compared with parental controls (CON), previously shown to have an aged phenotype in monolayer cultures (Sharples et al., 2011), seeded into 3D type I collagen matrices under uniaxial tension. 3D bioengineered constructs incorporating MPD cells had reduced myotube size and diameter vs. CON constructs. MPD constructs were characterized by reduced peak force development over 24 h after cell seeding, reduced transcript expression of remodelling matrix metalloproteinases, MMP2 and MMP9, with reduced differentiation/hypertrophic potential shown by reduced IGF-I, IGF-IR, IGF-IEa, MGF mRNA. Increased IGFBP2 and myostatin in MPD vs. CON constructs also suggested impaired differentiation/reduced regenerative potential. Overall, 3D bioengineered skeletal muscle constructs represent an in vitro model of the in vivo cell niche with MPD constructs displaying similar characteristics to ageing/atrophied muscle in vivo, thus potentially providing a future test bed for therapeutic interventions to contest muscle degeneration with age.
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Affiliation(s)
- Adam P Sharples
- Muscle Cellular and Molecular Physiology Research Group (MCMPRG), Institute for Sport and Physical Activity Research (ISPAR Bedford), University of Bedfordshire, Bedford, UK.
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MmNEU3 sialidase over-expression in C2C12 myoblasts delays differentiation and induces hypertrophic myotube formation. J Cell Biochem 2012; 113:2967-78. [DOI: 10.1002/jcb.24174] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Al-Shanti N, Stewart CE. Inhibitory effects of IL-6 on IGF-1 activity in skeletal myoblasts could be mediated by the activation of SOCS-3. J Cell Biochem 2012; 113:923-33. [PMID: 22033984 DOI: 10.1002/jcb.23420] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In elderly people, low and high levels of insulin-like growth factor 1 (IGF-1) and interleukin-6 (IL-6), respectively, are well documented and may contribute to reduced muscle mass and poor muscle function of ageing and suggesting a biological interactions between IGF-1 and IL-6. However, the dual effect of IGF-1/IL-6 on skeletal muscle differentiation and proliferation has not been fully investigated. We therefore hypothesised that IL-6 impairs the biological activity of IGF-1 in skeletal muscle through inhibiting its signalling pathways, ERK1/2 and Akt. Our aim was to examine the combined effects of these factors on models of muscle wasting, with objectives to examine skeletal muscle differentiation and proliferation using the murine C2 skeletal muscle cell line. Cells were cultured with DM, IGF-1 and IL-6 alone (control treatments), or co-cultured with IGF-1/IL-6. Co-incubation of C2 cells in IGF-1 plus IL-6 resulted in maximal cell death (22 ± 4%; P < 0.005) compared with control treatments (14 ± 2.9%). This was also confirmed by cyclin D1 expression levels in co-incubation treatments (7 ± 3.5%; P < 0.05) compared with control treatments (≈ 23%). The expression levels of myogenic-specific transcriptional factor mRNAs (myoD and myogenin) were also significantly (P < 0.005) reduced by 70% and 90%, respectively, under the co-incubation regimes, compared with control treatments. Signalling investigations showed significant phosphorylation reduction by 20%, (P < 0.05) of ERK1/2 and Akt in co-incubation treatments relative to either treatment alone. Expression studies for SOCS-3 (1.6-fold ± 0.08, P < 0.05) and IRS-1 (0.65-fold ± 0.13 P < 0.005) mRNAs showed significant elevation and reduction for both genes, respectively, in co-treatments relative to control treatments. These data may suggest that IL-6 exerts its inhibitory effects on IGF-1 signalling pathways (ERK1/2 and Akt) through blocking its receptor substrate IRS-1 by SOCS-3.
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Affiliation(s)
- Nasser Al-Shanti
- School of Healthcare Science, Institute for Biomedical Research into Human Movement and Health, Manchester Metropolitan University, Oxford Road, Manchester, M1 5GD, England, UK.
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Ceccarelli G, Benedetti L, Galli D, Prè D, Silvani G, Crosetto N, Magenes G, Cusella De Angelis MG. Low-amplitude high frequency vibration down-regulates myostatin and atrogin-1 expression, two components of the atrophy pathway in muscle cells. J Tissue Eng Regen Med 2012; 8:396-406. [PMID: 22711460 DOI: 10.1002/term.1533] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Revised: 01/18/2012] [Accepted: 04/04/2012] [Indexed: 11/07/2022]
Abstract
Whole body vibration (WBV) is a very widespread mechanical stimulus used in physical therapy, rehabilitation and fitness centres. It has been demonstrated that vibration induces improvements in muscular strength and performance and increases bone density. We investigated the effects of low-amplitude, high frequency vibration (HFV) at the cellular and tissue levels in muscle. We developed a system to produce vibrations adapted to test several parameters in vitro and in vivo. For in vivo experiments, we used newborn CD1 wild-type mice, for in vitro experiments, we isolated satellite cells from 6-day-old CD1 mice, while for proliferation studies, we used murine cell lines. Animals and cells were treated with high frequency vibration at 30 Hz. We analyzed the effects of mechanical stimulation on muscle hypertrophy/atrophy pathways, fusion enhancement of myoblast cells and modifications in the proliferation rate of cells. Results demonstrated that mechanical vibration strongly down-regulates atrophy genes both in vivo and in vitro. The in vitro experiments indicated that mechanical stimulation promotes fusion of satellite cells treated directly in culture compared to controls. Finally, proliferation experiments indicated that stimulated cells had a decreased growth rate compared to controls. We concluded that vibration treatment at 30 Hz is effective in suppressing the atrophy pathway both in vivo and in vitro and enhances fusion of satellite muscle cells.
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Affiliation(s)
- Gabriele Ceccarelli
- Dipartimento di Medicina Sperimentale, University of Pavia, Italy; Centro di Ingegneria Tissutale, University of Pavia, Italy
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Sharples AP, Al-Shanti N, Lewis MP, Stewart CE. Reduction of myoblast differentiation following multiple population doublings in mouse C2 C12 cells: a model to investigate ageing? J Cell Biochem 2012; 112:3773-85. [PMID: 21826704 DOI: 10.1002/jcb.23308] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Ageing skeletal muscle displays declines in size, strength, and functional capacity. Given the acknowledged role that the systemic environment plays in reduced regeneration (Conboy et al. [2005] Nature 433: 760-764), the role of resident satellite cells (termed myoblasts upon activation) is relatively dismissed, where, multiple cellular divisions in-vivo throughout the lifespan could also impact on muscular deterioration. Using a model of multiple population doublings (MPD) in-vitro thus provided a system in which to investigate the direct impact of extensive cell duplications on muscle cell behavior. C(2) C(12) mouse skeletal myoblasts (CON) were used fresh or following 58 population doublings (MPD). As a result of multiple divisions, reduced morphological and biochemical (creatine kinase, CK) differentiation were observed. Furthermore, MPD cells had significantly increased cells in the S and decreased cells in the G1 phases of the cell cycle versus CON, following serum withdrawal. These results suggest continued cycling rather than G1 exit and thus reduced differentiation (myotube atrophy) occurs in MPD muscle cells. These changes were underpinned by significant reductions in transcript expression of: IGF-I and myogenic regulatory factors (myoD and myogenin) together with elevated IGFBP5. Signaling studies showed that decreased differentiation in MPD was associated with decreased phosphorylation of Akt, and with later increased phosphorylation of JNK1/2. Chemical inhibition of JNK1/2 (SP600125) in MPD cells increased IGF-I expression (non-significantly), however, did not enhance differentiation. This study provides a potential model and molecular mechanisms for deterioration in differentiation capacity in skeletal muscle cells as a consequence of multiple population doublings that would potentially contribute to the ageing process.
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Affiliation(s)
- Adam P Sharples
- Faculty of Science and Engineering, Institute for Biomedical Research into Human Movement and Health (IRM), Manchester Metropolitan University, John Dalton Building, Oxford Road, Manchester, UK.
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