1
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Agca S, Kir S. EDA2R-NIK signaling in cancer cachexia. Curr Opin Support Palliat Care 2024; 18:126-131. [PMID: 38801457 DOI: 10.1097/spc.0000000000000705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
PURPOSE OF REVIEW Cachexia is a debilitating condition causing weight loss and skeletal muscle wasting that negatively influences treatment and survival of cancer patients. The objective of this review is to describe recent discoveries on the role of a novel signaling pathway involving ectodysplasin A2 receptor (EDA2R) and nuclear factor κB (NFκB)-inducing kinase (NIK) in muscle atrophy. RECENT FINDINGS Studies identified tumor-induced upregulation of EDA2R expression in muscle tissues in pre-clinical cachexia models and patients with various cancers. Activation of EDA2R by its ligand promoted atrophy in cultured myotubes and muscle tissue, which depended on NIK activity. The non-canonical NFκB pathway via NIK also stimulated muscle atrophy. Mice lacking EDA2R or NIK were protected from muscle loss due to tumors. Tumor-induced cytokine oncostatin M (OSM) upregulated EDA2R expression in muscles whereas OSM receptor-deficient mice were resistant to muscle wasting. SUMMARY Recent discoveries revealed a mechanism involving EDA2R-NIK signaling and OSM that drives cancer-associated muscle loss, opening up new directions for designing anti-cachexia treatments. The therapeutic potential of targeting this mechanism to prevent muscle loss should be further investigated. Future research should also explore broader implications of the EDA2R-NIK pathway in other muscle wasting diseases and overall muscle health.
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Affiliation(s)
- Samet Agca
- Department of Molecular Biology and Genetics, Koc University, Istanbul, Turkey
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2
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Cheon YH, Lee CH, Chung CH, Kim JY, Lee MS. Vigeo Promotes Myotube Differentiation and Protects Dexamethasone-Induced Skeletal Muscle Atrophy via Regulating the Protein Degradation, AKT/mTOR, and AMPK/Sirt-1/PGC1α Signaling Pathway In Vitro and In Vivo. Nutrients 2024; 16:2687. [PMID: 39203823 PMCID: PMC11357481 DOI: 10.3390/nu16162687] [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: 07/12/2024] [Revised: 08/01/2024] [Accepted: 08/12/2024] [Indexed: 09/03/2024] Open
Abstract
Sarcopenia, a condition caused by an imbalance between muscle growth and loss, can severely affect the quality of life of elderly patients with metabolic, inflammatory, and cancer diseases. Vigeo, a nuruk-fermented extract of three plants (Eleutherococcus senticosus Maxim (ESM), Achyranthes japonica (Miq.) Nakai (AJN), and Atractylodes japonica Koidzumi (AJK)) has been reported to have anti-osteoporotic effects. However, evidence of the effects of Vigeo on muscle atrophy is not available. Here, in the in vivo model of dexamethasone (Dex)-induced muscle atrophy, Vigeo treatment significantly reversed Dex-induced decreases in calf muscle volume, gastrocnemius (GA) muscle weight, and histological cross-section area. In addition, in mRNA and protein analyses isolated from GA muscle, we observed that Vigeo significantly protected against Dex-induced mouse muscle atrophy by inhibiting protein degradation regulated by atrogin and MuRF-1. Moreover, we demonstrated that Vigeo significantly promoted C2C12 cell line differentiation, as evidenced by the increased width and length of myotubes, and the increased number of fused myotubes with three or more nuclei. Vigeo alleviated the formation of myotubes compared to the control group. Vigeo also significantly increased the mRNA and protein expression of myosin heavy chain (MyHC), MyoD, and myogenin compared to that in the control. Vigeo treatment significantly reduced the mRNA and protein expression of muscle degradation markers atrogin-1 and muscle RING Finger 1 (MuRF-1) in the C2C12 cell line in vitro. Vigeo also activated the AMP-activated protein kinase (AMPK)/silent information regulator 1 (Sirt-1)/peroxisome proliferator-activated receptor-γ co-activator-1α (PGC1α) mitochondrial biogenesis pathway and the Akt/mTOR protein synthesis signaling pathway in Dex-induced myotube atrophy. These findings suggest that Vigeo may have protective effects against Dex-induced muscle atrophy. Therefore, we propose Vigeo as a supplement or potential therapeutic agent to prevent or treat sarcopenia accompanied by muscle atrophy and degeneration.
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Affiliation(s)
- Yoon-Hee Cheon
- Musculoskeletal and Immune Disease Research Institute, School of Medicine, Wonkwang University, 460 Iksandae-ro, Iksan 54538, Republic of Korea; (Y.-H.C.); (C.-H.L.); (C.-H.C.)
| | - Chang-Hoon Lee
- Musculoskeletal and Immune Disease Research Institute, School of Medicine, Wonkwang University, 460 Iksandae-ro, Iksan 54538, Republic of Korea; (Y.-H.C.); (C.-H.L.); (C.-H.C.)
- Division of Rheumatology, Department of Internal Medicine, Wonkwang University Hospital, 460 Iksandae-ro, Iksan 54538, Republic of Korea
| | - Chong-Hyuk Chung
- Musculoskeletal and Immune Disease Research Institute, School of Medicine, Wonkwang University, 460 Iksandae-ro, Iksan 54538, Republic of Korea; (Y.-H.C.); (C.-H.L.); (C.-H.C.)
- Division of Rheumatology, Department of Internal Medicine, Wonkwang University Hospital, 460 Iksandae-ro, Iksan 54538, Republic of Korea
| | - Ju-Young Kim
- Musculoskeletal and Immune Disease Research Institute, School of Medicine, Wonkwang University, 460 Iksandae-ro, Iksan 54538, Republic of Korea; (Y.-H.C.); (C.-H.L.); (C.-H.C.)
| | - Myeung-Su Lee
- Musculoskeletal and Immune Disease Research Institute, School of Medicine, Wonkwang University, 460 Iksandae-ro, Iksan 54538, Republic of Korea; (Y.-H.C.); (C.-H.L.); (C.-H.C.)
- Division of Rheumatology, Department of Internal Medicine, Wonkwang University Hospital, 460 Iksandae-ro, Iksan 54538, Republic of Korea
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3
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Özen SD, Kir S. Ectodysplasin A2 receptor signaling in skeletal muscle pathophysiology. Trends Mol Med 2024; 30:471-483. [PMID: 38443222 DOI: 10.1016/j.molmed.2024.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 02/05/2024] [Accepted: 02/09/2024] [Indexed: 03/07/2024]
Abstract
Skeletal muscle is essential in generating mechanical force and regulating energy metabolism and body temperature. Pathologies associated with muscle tissue often lead to impaired physical activity and imbalanced metabolism. Recently, ectodysplasin A2 receptor (EDA2R) signaling has been shown to promote muscle loss and glucose intolerance. Upregulated EDA2R expression in muscle tissue was associated with aging, denervation, cancer cachexia, and muscular dystrophies. Here, we describe the roles of EDA2R signaling in muscle pathophysiology, including muscle atrophy, insulin resistance, and aging-related sarcopenia. We also discuss the EDA2R pathway, which involves EDA-A2 as the ligand and nuclear factor (NF)κB-inducing kinase (NIK) as a downstream mediator, and the therapeutic potential of targeting these proteins in the treatment of muscle wasting and metabolic dysfunction.
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Affiliation(s)
- Sevgi Döndü Özen
- Department of Molecular Biology and Genetics, Koc University, Istanbul 34450, Turkey
| | - Serkan Kir
- Department of Molecular Biology and Genetics, Koc University, Istanbul 34450, Turkey.
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4
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Domaniku A, Bilgic SN, Kir S. Muscle wasting: emerging pathways and potential drug targets. Trends Pharmacol Sci 2023; 44:705-718. [PMID: 37596181 DOI: 10.1016/j.tips.2023.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 07/28/2023] [Accepted: 07/28/2023] [Indexed: 08/20/2023]
Abstract
Muscle wasting is a serious comorbidity associated with many disorders, including cancer, kidney disease, heart failure, and aging. Progressive loss of skeletal muscle mass negatively influences prognosis and survival, and is often accompanied by frailty and poor quality of life. Clinical trials testing therapeutics against muscle wasting have yielded limited success. Some therapies improved muscle mass in patients without appreciable differences in physical performance. This review article discusses emerging pathways that regulate muscle atrophy, including oncostatin M (OSM) and ectodysplasin A2 (EDA2) receptor (EDA2R) signaling, outcomes of recent clinical trials, and potential drug targets for future therapies.
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Affiliation(s)
- Aylin Domaniku
- Department of Molecular Biology and Genetics, Koc University, Istanbul 34450, Turkey
| | - Sevval Nur Bilgic
- Department of Molecular Biology and Genetics, Koc University, Istanbul 34450, Turkey
| | - Serkan Kir
- Department of Molecular Biology and Genetics, Koc University, Istanbul 34450, Turkey.
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5
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Sawano S, Fukushima M, Akasaka T, Nakamura M, Tatsumi R, Ikeuchi Y, Mizunoya W. Up- and Downregulated Genes after Long-Term Muscle Atrophy Induced by Denervation in Mice Detected Using RNA-Seq. Life (Basel) 2023; 13:life13051111. [PMID: 37240756 DOI: 10.3390/life13051111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 04/24/2023] [Accepted: 04/27/2023] [Indexed: 05/28/2023] Open
Abstract
Skeletal muscle atrophy occurs rapidly as a result of inactivity. Although there are many reports on changes in gene expression during the early phase of muscle atrophy, the patterns of up-and downregulated gene expression after long-term and equilibrated muscle atrophy are poorly understood. In this study, we comprehensively examined the changes in gene expression in long-term denervated mouse muscles using RNA-Seq. The murine right sciatic nerve was denervated, and the mice were housed for five weeks. The cross-sectional areas of the hind limb muscles were measured using an X-ray CT system 35 days after denervation. After 28 d of denervation, the cross-sectional area of the muscle decreased to approximately 65% of that of the intact left muscle and reached a plateau. Gene expression in the soleus and extensor digitorum longus (EDL) muscles on the 36th day was analyzed using RNA-Seq and validated using RT-qPCR. RNA-Seq analysis revealed that three genes-Adora1, E230016M11Rik, and Gm10718-were upregulated and one gene-Gm20515-was downregulated in the soleus muscle; additionally, four genes-Adora1, E230016M11Rik, Pigh, and Gm15557-were upregulated and one gene-Fzd7-was downregulated in the EDL muscle (FDR < 0.05). Among these genes, E230016M11Rik, one of the long non-coding RNAs, was significantly upregulated in both the muscles. These findings indicate that E230016M11Rik could be a candidate gene for the maintenance of atrophied skeletal muscle size and an atrophic state.
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Affiliation(s)
- Shoko Sawano
- Department of Animal and Marine Bioresource Sciences, Graduate School of Agriculture, Kyushu University, Fukuoka 819-0395, Japan
- Department of Food and Life Science, School of Life and Environmental Science, Azabu University, Sagamihara 252-5201, Japan
| | - Misaki Fukushima
- Department of Animal and Marine Bioresource Sciences, Graduate School of Agriculture, Kyushu University, Fukuoka 819-0395, Japan
| | - Taiki Akasaka
- Department of Animal and Marine Bioresource Sciences, Graduate School of Agriculture, Kyushu University, Fukuoka 819-0395, Japan
| | - Mako Nakamura
- Department of Animal and Marine Bioresource Sciences, Graduate School of Agriculture, Kyushu University, Fukuoka 819-0395, Japan
| | - Ryuichi Tatsumi
- Department of Animal and Marine Bioresource Sciences, Graduate School of Agriculture, Kyushu University, Fukuoka 819-0395, Japan
| | - Yoshihide Ikeuchi
- Department of Animal and Marine Bioresource Sciences, Graduate School of Agriculture, Kyushu University, Fukuoka 819-0395, Japan
| | - Wataru Mizunoya
- Department of Animal and Marine Bioresource Sciences, Graduate School of Agriculture, Kyushu University, Fukuoka 819-0395, Japan
- Department of Animal Science and Biotechnology, School of Veterinary Medicine, Azabu University, Sagamihara 252-5201, Japan
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6
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Hughes DC, Baehr LM, Waddell DS, Sharples AP, Bodine SC. Ubiquitin Ligases in Longevity and Aging Skeletal Muscle. Int J Mol Sci 2022; 23:7602. [PMID: 35886949 PMCID: PMC9315556 DOI: 10.3390/ijms23147602] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/07/2022] [Accepted: 07/08/2022] [Indexed: 12/07/2022] Open
Abstract
The development and prevalence of diseases associated with aging presents a global health burden on society. One hallmark of aging is the loss of proteostasis which is caused in part by alterations to the ubiquitin-proteasome system (UPS) and lysosome-autophagy system leading to impaired function and maintenance of mass in tissues such as skeletal muscle. In the instance of skeletal muscle, the impairment of function occurs early in the aging process and is dependent on proteostatic mechanisms. The UPS plays a pivotal role in degradation of misfolded and aggregated proteins. For the purpose of this review, we will discuss the role of the UPS system in the context of age-related loss of muscle mass and function. We highlight the significant role that E3 ubiquitin ligases play in the turnover of key components (e.g., mitochondria and neuromuscular junction) essential to skeletal muscle function and the influence of aging. In addition, we will briefly discuss the contribution of the UPS system to lifespan. By understanding the UPS system as part of the proteostasis network in age-related diseases and disorders such as sarcopenia, new discoveries can be made and new interventions can be developed which will preserve muscle function and maintain quality of life with advancing age.
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Affiliation(s)
- David C. Hughes
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA; (L.M.B.); (S.C.B.)
| | - Leslie M. Baehr
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA; (L.M.B.); (S.C.B.)
| | - David S. Waddell
- Department of Biology, University of North Florida, Jacksonville, FL 32224, USA;
| | - Adam P. Sharples
- Institute for Physical Performance, Norwegian School of Sport Sciences (NiH), 0863 Oslo, Norway;
| | - Sue C. Bodine
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA; (L.M.B.); (S.C.B.)
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7
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Dunlap KR, Laskin GR, Waddell DS, Black AJ, Steiner JL, Vied C, Gordon BS. Aerobic exercise-mediated changes in the expression of glucocorticoid responsive genes in skeletal muscle differ across the day. Mol Cell Endocrinol 2022; 550:111652. [PMID: 35461977 DOI: 10.1016/j.mce.2022.111652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 03/30/2022] [Accepted: 04/18/2022] [Indexed: 10/18/2022]
Abstract
Glucocorticoids are released in response to acute aerobic exercise. The objective was to define changes in the expression of glucocorticoid target genes in skeletal muscle in response to acute aerobic exercise at different times of day. We identified glucocorticoid target genes altered in skeletal muscle by acute exercise by comparing data sets from rodents subjected to acute aerobic exercise in the light or dark cycles to data sets from C2C12 myotubes treated with glucocorticoids. The role of glucocorticoid receptor signaling and REDD1 protein in mediating gene expression was assessed in exercised mice. Changes to expression of glucocorticoid genes were greater when exercise occurred in the dark cycle. REDD1 was required for the induction of genes induced at both times of day. In all, the time of day at which aerobic exercise is conducted dictates changes to the expression of glucocorticoid target genes in skeletal muscle with REDD1 contributing to those changes.
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Affiliation(s)
- Kirsten R Dunlap
- Department of Nutrition and Integrative Physiology, Florida State University, 600 W. Cottage Avenue, Tallahassee, FL, 32306, USA
| | - Grant R Laskin
- Department of Nutrition and Integrative Physiology, Florida State University, 600 W. Cottage Avenue, Tallahassee, FL, 32306, USA
| | - David S Waddell
- Department of Biology, University of North Florida, 1 UNF Drive, Jacksonville, FL, 32224, USA
| | - Adam J Black
- Department of Cell Biology and Physiology, University of North Carolina, 111 Mason Farm Rd, Chapel Hill, NC, 27599, USA
| | - Jennifer L Steiner
- Department of Nutrition and Integrative Physiology, Florida State University, 600 W. Cottage Avenue, Tallahassee, FL, 32306, USA; Institute of Sports Sciences and Medicine, Florida State University, 600 W. Cottage Ave, Tallahassee, FL, 32306, USA
| | - Cynthia Vied
- Translational Sciences Laboratory, Florida State University College of Medicine, 1115 West Call Street, Tallahassee, FL, 32306, USA
| | - Bradley S Gordon
- Department of Nutrition and Integrative Physiology, Florida State University, 600 W. Cottage Avenue, Tallahassee, FL, 32306, USA; Institute of Sports Sciences and Medicine, Florida State University, 600 W. Cottage Ave, Tallahassee, FL, 32306, USA.
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8
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α-Arrestins and Their Functions: From Yeast to Human Health. Int J Mol Sci 2022; 23:ijms23094988. [PMID: 35563378 PMCID: PMC9105457 DOI: 10.3390/ijms23094988] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 04/26/2022] [Accepted: 04/27/2022] [Indexed: 12/10/2022] Open
Abstract
α-Arrestins, also called arrestin-related trafficking adaptors (ARTs), constitute a large family of proteins conserved from yeast to humans. Despite their evolutionary precedence over their extensively studied relatives of the β-arrestin family, α-arrestins have been discovered relatively recently, and thus their properties are mostly unexplored. The predominant function of α-arrestins is the selective identification of membrane proteins for ubiquitination and degradation, which is an important element in maintaining membrane protein homeostasis as well as global cellular metabolisms. Among members of the arrestin clan, only α-arrestins possess PY motifs that allow canonical binding to WW domains of Rsp5/NEDD4 ubiquitin ligases and the subsequent ubiquitination of membrane proteins leading to their vacuolar/lysosomal degradation. The molecular mechanisms of the selective substrate’s targeting, function, and regulation of α-arrestins in response to different stimuli remain incompletely understood. Several functions of α-arrestins in animal models have been recently characterized, including redox homeostasis regulation, innate immune response regulation, and tumor suppression. However, the molecular mechanisms of α-arrestin regulation and substrate interactions are mainly based on observations from the yeast Saccharomyces cerevisiae model. Nonetheless, α-arrestins have been implicated in health disorders such as diabetes, cardiovascular diseases, neurodegenerative disorders, and tumor progression, placing them in the group of potential therapeutic targets.
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9
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Zaripova KA, Kalashnikova EP, Belova SP, Kostrominova TY, Shenkman BS, Nemirovskaya TL. Role of Pannexin 1 ATP-Permeable Channels in the Regulation of Signaling Pathways during Skeletal Muscle Unloading. Int J Mol Sci 2021; 22:ijms221910444. [PMID: 34638792 PMCID: PMC8508840 DOI: 10.3390/ijms221910444] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/22/2021] [Accepted: 09/24/2021] [Indexed: 12/17/2022] Open
Abstract
Skeletal muscle unloading results in atrophy. We hypothesized that pannexin 1 ATP-permeable channel (PANX1) is involved in the response of muscle to unloading. We tested this hypothesis by blocking PANX1, which regulates efflux of ATP from the cytoplasm. Rats were divided into six groups (eight rats each): non-treated control for 1 and 3 days of the experiments (1C and 3C, respectively), 1 and 3 days of hindlimb suspension (HS) with placebo (1H and 3H, respectively), and 1 and 3 days of HS with PANX1 inhibitor probenecid (PRB; 1HP and 3HP, respectively). When compared with 3C group there was a significant increase in ATP in soleus muscle of 3H and 3HP groups (32 and 51%, respectively, p < 0.05). When compared with 3H group, 3HP group had: (1) lower mRNA expression of E3 ligases MuRF1 and MAFbx (by 50 and 38% respectively, p < 0.05) and MYOG (by 34%, p < 0.05); (2) higher phosphorylation of p70S6k and p90RSK (by 51 and 35% respectively, p < 0.05); (3) lower levels of phosphorylated eEF2 (by 157%, p < 0.05); (4) higher level of phosphorylated GSK3β (by 189%, p < 0.05). In conclusion, PANX1 ATP-permeable channels are involved in the regulation of muscle atrophic processes by modulating expression of E3 ligases, and protein translation and elongation processes during unloading.
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Affiliation(s)
- Ksenia A. Zaripova
- Institute of Biomedical Problems, RAS, 123007 Moscow, Russia; (K.A.Z.); (E.P.K.); (S.P.B.); (B.S.S.)
| | - Ekaterina P. Kalashnikova
- Institute of Biomedical Problems, RAS, 123007 Moscow, Russia; (K.A.Z.); (E.P.K.); (S.P.B.); (B.S.S.)
| | - Svetlana P. Belova
- Institute of Biomedical Problems, RAS, 123007 Moscow, Russia; (K.A.Z.); (E.P.K.); (S.P.B.); (B.S.S.)
| | - Tatiana Y. Kostrominova
- Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine-Northwest, Gary, IN 46408, USA;
| | - Boris S. Shenkman
- Institute of Biomedical Problems, RAS, 123007 Moscow, Russia; (K.A.Z.); (E.P.K.); (S.P.B.); (B.S.S.)
| | - Tatiana L. Nemirovskaya
- Institute of Biomedical Problems, RAS, 123007 Moscow, Russia; (K.A.Z.); (E.P.K.); (S.P.B.); (B.S.S.)
- Correspondence:
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10
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Dörner MF, Boknik P, Köpp F, Buchwalow IB, Neumann J, Gergs U. Mechanisms of Systolic Cardiac Dysfunction in PP2A, PP5 and PP2AxPP5 Double Transgenic Mice. Int J Mol Sci 2021; 22:ijms22179448. [PMID: 34502355 PMCID: PMC8431312 DOI: 10.3390/ijms22179448] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 08/26/2021] [Accepted: 08/26/2021] [Indexed: 12/15/2022] Open
Abstract
As part of our ongoing studies on the potential pathophysiological role of serine/threonine phosphatases (PP) in the mammalian heart, we have generated transgenic mice with cardiac muscle cell-specific overexpression of PP2Acα (PP2A) and PP5 (PP5). For further studies we crossbred PP2A and PP5 mice to obtain PP2AxPP5 double transgenic mice (PP2AxPP5, DT) and compared them with littermate wild-type mice (WT) serving as a control. The mortality of DT mice was greatly enhanced vs. other genotypes. Cardiac fibrosis was noted histologically and mRNA levels of collagen 1α, collagen 3α and fibronectin 1 were augmented in DT. DT and PP2A mice exhibited an increase in relative heart weight. The ejection fraction (EF) was reduced in PP2A and DT but while the EF of PP2A was nearly normalized after β-adrenergic stimulation by isoproterenol, it was almost unchanged in DT. Moreover, left atrial preparations from DT were less sensitive to isoproterenol treatment both under normoxic conditions and after hypoxia. In addition, levels of the hypertrophy markers atrial natriuretic peptide and B-type natriuretic peptide as well as the inflammation markers interleukin 6 and nuclear factor kappa B were increased in DT. PP2A enzyme activity was enhanced in PP2A vs. WT but similar to DT. This was accompanied by a reduced phosphorylation state of phospholamban at serine-16. Fittingly, the relaxation times in left atria from DT were prolonged. In summary, cardiac co-overexpression of PP2A and PP5 were detrimental to animal survival and cardiac function, and the mechanism may involve dephosphorylation of important regulatory proteins but also fibrosis and inflammation.
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Affiliation(s)
- Mara-Francine Dörner
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, D-06097 Halle, Germany; (M.-F.D.); (F.K.); (J.N.)
- Mibe GmbH Arzneimittel, D-06796 Brehna, Germany
| | - Peter Boknik
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Westfälische Wilhelms-Universität, D-48149 Münster, Germany;
| | - Friedrich Köpp
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, D-06097 Halle, Germany; (M.-F.D.); (F.K.); (J.N.)
| | - Igor B. Buchwalow
- Institute for Hematopathology, Fangdieckstr. 75a, D-22547 Hamburg, Germany;
| | - Joachim Neumann
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, D-06097 Halle, Germany; (M.-F.D.); (F.K.); (J.N.)
| | - Ulrich Gergs
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, D-06097 Halle, Germany; (M.-F.D.); (F.K.); (J.N.)
- Correspondence: ; Tel.: +49-345-557-4093
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11
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Smith AL, Gjoka E, Izhar M, Novo KJ, Mason BC, De Las Casas A, Waddell DS. FGGY carbohydrate kinase domain containing is expressed and alternatively spliced in skeletal muscle and attenuates MAP kinase and Akt signaling. Gene 2021; 800:145836. [PMID: 34280510 DOI: 10.1016/j.gene.2021.145836] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 06/09/2021] [Accepted: 07/13/2021] [Indexed: 01/03/2023]
Abstract
Skeletal muscle atrophy can result from a range of physiological conditions, including denervation, immobilization, hindlimb unweighting, and aging. To better characterize the molecular genetic events of atrophy, a microarray analysis revealed that FGGY carbohydrate kinase domain containing (Fggy) is expressed in skeletal muscle and is induced in response to denervation. Bioinformatic analysis of the Fggy gene locus revealed two validated isoforms with alternative transcription initiation sites that we have designated Fggy-L-552 and Fggy-S-387. Additionally, we cloned two novel alternative splice variants, designated Fggy-L-482 and Fggy-S-344, from cultured muscle cells suggesting that at least four Fggy splice variants are expressed in skeletal muscle. Quantitative RT-PCR was performed using RNA isolated from muscle cells and primers designed to distinguish the four alternative Fggy transcripts and found that the Fggy-L transcripts are more highly expressed during myoblast differentiation, while the Fggy-S transcripts show relatively stable expression in proliferating myoblasts and differentiated myotubes. Confocal fluorescent microscopy revealed that the Fggy-L variants appear to localize evenly throughout the cytoplasm, while the Fggy-S variants produce a more punctuate cytoplasmic localization pattern in proliferating muscle cells. Finally, ectopic expression of Fggy-L-552 and Fggy-S-387 resulted in inhibition of muscle cell differentiation and attenuation of the MAP kinase and Akt signaling pathways. The identification and characterization of novel genes such as Fggy helps to improve our understanding of the molecular and cellular events that lead to atrophy and may eventually result in the identification of new therapeutic targets for the treatment of muscle wasting.
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Affiliation(s)
- Anastasia L Smith
- University of North Florida, Department of Biology, 1 UNF Drive, Jacksonville, FL 32224, USA
| | - Erisa Gjoka
- University of North Florida, Department of Biology, 1 UNF Drive, Jacksonville, FL 32224, USA
| | - Mahnoor Izhar
- University of North Florida, Department of Biology, 1 UNF Drive, Jacksonville, FL 32224, USA
| | - Karla J Novo
- University of North Florida, Department of Biology, 1 UNF Drive, Jacksonville, FL 32224, USA
| | - Brittany C Mason
- University of North Florida, Department of Biology, 1 UNF Drive, Jacksonville, FL 32224, USA
| | - Annabella De Las Casas
- University of North Florida, Department of Biology, 1 UNF Drive, Jacksonville, FL 32224, USA
| | - David S Waddell
- University of North Florida, Department of Biology, 1 UNF Drive, Jacksonville, FL 32224, USA.
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12
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Gu X, Jin B, Qi Z, Yin X. Identification of potential microRNAs and KEGG pathways in denervation muscle atrophy based on meta-analysis. Sci Rep 2021; 11:13560. [PMID: 34193880 PMCID: PMC8245453 DOI: 10.1038/s41598-021-92489-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Accepted: 05/24/2021] [Indexed: 12/28/2022] Open
Abstract
The molecular mechanism of muscle atrophy has been studied a lot, but there is no comprehensive analysis focusing on the denervated muscle atrophy. The gene network that controls the development of denervated muscle atrophy needs further elucidation. We examined differentially expressed genes (DEGs) from five denervated muscle atrophy microarray datasets and predicted microRNAs that target these DEGs. We also included the differentially expressed microRNAs datasets of denervated muscle atrophy in previous studies as background information to identify potential key microRNAs. Finally, we compared denervated muscle atrophy with disuse muscle atrophy caused by other reasons, and obtained the Den-genes which only differentially expressed in denervated muscle atrophy. In this meta-analysis, we obtained 429 up-regulated genes, 525 down-regulated genes and a batch of key microRNAs in denervated muscle atrophy. We found eight important microRNA-mRNA interactions (miR-1/Jun, miR-1/Vegfa, miR-497/Vegfa, miR-23a/Vegfa, miR-206/Vegfa, miR-497/Suclg1, miR-27a/Suclg1, miR-27a/Mapk14). The top five KEGG pathways enriched by Den-genes are Insulin signaling pathway, T cell receptor signaling pathway, MAPK signaling pathway, Toll-like receptor signaling pathway and B cell receptor signaling pathway. Our research has delineated the RNA regulatory network of denervated muscle atrophy, and uncovered the specific genes and terms in denervated muscle atrophy.
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Affiliation(s)
- Xinyi Gu
- Department of Orthopedics and Traumatology, Peking University People's Hospital, Beijing, 100044, China.,Key Laboratory of Trauma and Neural Regeneration (Peking University), Beijing, 100044, China
| | - Bo Jin
- Department of Orthopedics and Traumatology, Peking University People's Hospital, Beijing, 100044, China.,Key Laboratory of Trauma and Neural Regeneration (Peking University), Beijing, 100044, China
| | - Zhidan Qi
- Department of Orthopedics and Traumatology, Peking University People's Hospital, Beijing, 100044, China.,Key Laboratory of Trauma and Neural Regeneration (Peking University), Beijing, 100044, China
| | - Xiaofeng Yin
- Department of Orthopedics and Traumatology, Peking University People's Hospital, Beijing, 100044, China. .,Key Laboratory of Trauma and Neural Regeneration (Peking University), Beijing, 100044, China.
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13
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The emerging role of the sympathetic nervous system in skeletal muscle motor innervation and sarcopenia. Ageing Res Rev 2021; 67:101305. [PMID: 33610815 DOI: 10.1016/j.arr.2021.101305] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 01/06/2021] [Accepted: 02/15/2021] [Indexed: 12/30/2022]
Abstract
Examining neural etiologic factors'role in the decline of neuromuscular function with aging is essential to our understanding of the mechanisms underlying sarcopenia, the age-dependent decline in muscle mass, force and power. Innervation of the skeletal muscle by both motor and sympathetic axons has been established, igniting interest in determining how the sympathetic nervous system (SNS) affect skeletal muscle composition and function throughout the lifetime. Selective expression of the heart and neural crest derivative 2 gene in peripheral SNs increases muscle mass and force regulating skeletal muscle sympathetic and motor innervation; improving acetylcholine receptor stability and NMJ transmission; preventing inflammation and myofibrillar protein degradation; increasing autophagy; and probably enhancing protein synthesis. Elucidating the role of central SNs will help to define the coordinated response of the visceral and neuromuscular system to physiological and pathological challenges across ages. This review discusses the following questions: (1) Does the SNS regulate skeletal muscle motor innervation? (2) Does the SNS regulate presynaptic and postsynaptic neuromuscular junction (NMJ) structure and function? (3) Does sympathetic neuron (SN) regulation of NMJ transmission decline with aging? (4) Does maintenance of SNs attenuate aging sarcopenia? and (5) Do central SN group relays influence sympathetic and motor muscle innervation?
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14
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Bollmann P, Werner F, Jaron M, Bruns TA, Wache H, Runte J, Boknik P, Kirchhefer U, Müller FU, Buchwalow IB, Rothemund S, Neumann J, Gergs U. Initial Characterization of Stressed Transgenic Mice With Cardiomyocyte-Specific Overexpression of Protein Phosphatase 2C. Front Pharmacol 2021; 11:591773. [PMID: 33597873 PMCID: PMC7883593 DOI: 10.3389/fphar.2020.591773] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 12/07/2020] [Indexed: 12/17/2022] Open
Abstract
As part of our ongoing studies on the potential pathophysiological role of serine/threonine phosphatases (PP) in the mammalian heart, we have generated mice with cardiac-specific overexpression of PP2Cβ (PP2C-TG) and compared them with littermate wild type mice (WT) serving as a control. Cardiac fibrosis was noted histologically in PP2C-TG. Collagen 1a, interleukin-6 and the natriuretic peptides ANP and BNP were augmented in PP2C-TG vs. WT (p < 0.05). Left atrial preparations from PP2C-TG were less resistant to hypoxia than atria from WT. PP2C-TG maintained cardiac function after the injection of lipopolysaccharide (LPS, a model of sepsis) and chronic isoproterenol treatment (a model of heart failure) better than WT. Crossbreeding of PP2C-TG mice with PP2A-TG mice (a genetic model of heart failure) resulted in double transgenic (DT) mice that exhibited a pronounced increase of heart weight in contrast to the mild hypertrophy noted in the mono-transgenic mice. The ejection fraction was reduced in PP2C-TG and in PP2A-TG mice compared with WT, but the reduction was the highest in DT compared with WT. PP2A enzyme activity was enhanced in PP2A-TG and DT mice compared with WT and PP2C-TG mice. In summary, cardiac overexpression of PP2Cβ and co-overexpression of both the catalytic subunit of PP2A and PP2Cβ were detrimental to cardiac function. PP2Cβ overexpression made cardiac preparations less resistant to hypoxia than WT, leading to fibrosis, but PP2Cβ overexpression led to better adaptation to some stressors, such as LPS or chronic β-adrenergic stimulation. Hence, the effect of PP2Cβ is context sensitive.
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Affiliation(s)
- Paula Bollmann
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Franziska Werner
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Marko Jaron
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Tom A Bruns
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Hartmut Wache
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Jochen Runte
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Peter Boknik
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Westfälische Wilhelms-Universität, Münster, Germany
| | - Uwe Kirchhefer
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Westfälische Wilhelms-Universität, Münster, Germany
| | - Frank U Müller
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Westfälische Wilhelms-Universität, Münster, Germany
| | | | | | - Joachim Neumann
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Ulrich Gergs
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
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15
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Gorza L, Sorge M, Seclì L, Brancaccio M. Master Regulators of Muscle Atrophy: Role of Costamere Components. Cells 2021; 10:cells10010061. [PMID: 33401549 PMCID: PMC7823551 DOI: 10.3390/cells10010061] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 12/28/2020] [Accepted: 12/29/2020] [Indexed: 12/11/2022] Open
Abstract
The loss of muscle mass and force characterizes muscle atrophy in several different conditions, which share the expression of atrogenes and the activation of their transcriptional regulators. However, attempts to antagonize muscle atrophy development in different experimental contexts by targeting contributors to the atrogene pathway showed partial effects in most cases. Other master regulators might independently contribute to muscle atrophy, as suggested by our recent evidence about the co-requirement of the muscle-specific chaperone protein melusin to inhibit unloading muscle atrophy development. Furthermore, melusin and other muscle mass regulators, such as nNOS, belong to costameres, the macromolecular complexes that connect sarcolemma to myofibrils and to the extracellular matrix, in correspondence with specific sarcomeric sites. Costameres sense a mechanical load and transduce it both as lateral force and biochemical signals. Recent evidence further broadens this classic view, by revealing the crucial participation of costameres in a sarcolemmal “signaling hub” integrating mechanical and humoral stimuli, where mechanical signals are coupled with insulin and/or insulin-like growth factor stimulation to regulate muscle mass. Therefore, this review aims to enucleate available evidence concerning the early involvement of costamere components and additional putative master regulators in the development of major types of muscle atrophy.
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Affiliation(s)
- Luisa Gorza
- Department of Biomedical Sciences, University of Padova, 35121 Padova, Italy
- Correspondence:
| | - Matteo Sorge
- Department of Molecular Biotechnology and Health Sciences, University of Torino, 10126 Torino, Italy; (M.S.); (L.S.); (M.B.)
| | - Laura Seclì
- Department of Molecular Biotechnology and Health Sciences, University of Torino, 10126 Torino, Italy; (M.S.); (L.S.); (M.B.)
| | - Mara Brancaccio
- Department of Molecular Biotechnology and Health Sciences, University of Torino, 10126 Torino, Italy; (M.S.); (L.S.); (M.B.)
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16
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Dai J, Xiang Y, Fu D, Xu L, Jiang J, Xu J. Ficus carica L. Attenuates Denervated Skeletal Muscle Atrophy via PPARα/NF-κB Pathway. Front Physiol 2020; 11:580223. [PMID: 33343385 PMCID: PMC7744683 DOI: 10.3389/fphys.2020.580223] [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: 07/05/2020] [Accepted: 10/13/2020] [Indexed: 12/31/2022] Open
Abstract
Treatment options for denervated skeletal muscle atrophy are limited, in part because the underlying molecular mechanisms are not well understood. Unlike previous transcriptomics studies conducted in rodent models of peripheral nerve injury, in the present study, we performed high-throughput sequencing with denervated atrophic biceps muscle and normal (non-denervated) sternocleidomastoid muscle samples obtained from four brachial plexus injury (BPI) patients. We also investigated whether Ficus carica L. (FCL.) extract can suppress denervated muscle atrophy in a mouse model, along with the mechanism of action. We identified 1471 genes that were differentially expressed between clinical specimens of atrophic and normal muscle, including 771 that were downregulated and 700 that were upregulated. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses revealed that the differentially expressed genes were mainly enriched in the GO terms “structural constituent of muscle,” “Z disc,” “M band,” and “striated muscle contraction,” as well as “Cell adhesion molecules,” “Glycolysis/Gluconeogenesis,” “Peroxisome proliferator-activated receptor alpha (PPARα) signaling pathway,” and “P53 signaling pathway.” In experiments using mice, the reduction in wet weight and myofiber diameter in denervated muscle was improved by FCL. extract compared to saline administration, which was accompanied by downregulation of the proinflammatory cytokines interleukin (IL)-1β and IL-6. Moreover, although both denervated groups showed increased nuclear factor (NF)-κB activation and PPARα expression, the degree of NF-κB activation was lower while PPARα and inhibitor of NF-κB IκBα expression was higher in FCL. extract-treated mice. Thus, FCL. extract suppresses denervation-induced inflammation and attenuates muscle atrophy by enhancing PPARα expression and inhibiting NF-κB activation. These findings suggest that FCL. extract has therapeutic potential for preventing denervation-induced muscle atrophy caused by peripheral nerve injury or disease.
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Affiliation(s)
- Junxi Dai
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, China.,Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai, China.,Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, China
| | - Yaoxian Xiang
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, China.,Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai, China.,Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, China
| | - Da Fu
- Central Laboratory, Shanghai Tenth People's Hospital, Shanghai, China
| | - Lei Xu
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, China.,Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai, China.,Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, China
| | - Junjian Jiang
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, China.,Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai, China.,Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, China
| | - Jianguang Xu
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, China.,Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai, China.,Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, China.,School of Rehabilitation Science, Shanghai University of Traditional Chinese Medicine, Shanghai, China
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17
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Hughes DC, Baehr LM, Driscoll JR, Lynch SA, Waddell DS, Bodine SC. Identification and characterization of Fbxl22, a novel skeletal muscle atrophy-promoting E3 ubiquitin ligase. Am J Physiol Cell Physiol 2020; 319:C700-C719. [PMID: 32783651 DOI: 10.1152/ajpcell.00253.2020] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Muscle-specific E3 ubiquitin ligases have been identified in muscle atrophy-inducing conditions. The purpose of the current study was to explore the functional role of F-box and leucine-rich protein 22 (Fbxl22), and a newly identified splice variant (Fbxl22-193), in skeletal muscle homeostasis and neurogenic muscle atrophy. In mouse C2C12 muscle cells, promoter fragments of the Fbxl22 gene were cloned and fused with the secreted alkaline phosphatase reporter gene to assess the transcriptional regulation of Fbxl22. The tibialis anterior muscles of male C57/BL6 mice (12-16 wk old) were electroporated with expression plasmids containing the cDNA of two Fbxl22 splice variants and tissues collected after 7, 14, and 28 days. Gastrocnemius muscles of wild-type and muscle-specific RING finger 1 knockout (MuRF1 KO) mice were electroporated with an Fbxl22 RNAi or empty plasmid and denervated 3 days posttransfection, and tissues were collected 7 days postdenervation. The full-length gene and novel splice variant are transcriptionally induced early (after 3 days) during neurogenic muscle atrophy. In vivo overexpression of Fbxl22 isoforms in mouse skeletal muscle leads to evidence of myopathy/atrophy, suggesting that both are involved in the process of neurogenic muscle atrophy. Knockdown of Fbxl22 in the muscles of MuRF1 KO mice resulted in significant additive muscle sparing 7 days after denervation. Targeting two E3 ubiquitin ligases appears to have a strong additive effect on protecting muscle mass loss with denervation, and these findings have important implications in the development of therapeutic strategies to treat muscle atrophy.
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Affiliation(s)
- David C Hughes
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Leslie M Baehr
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Julia R Driscoll
- Department of Biology, University of North Florida, Jacksonville, Florida
| | - Sarah A Lynch
- Department of Biology, University of North Florida, Jacksonville, Florida
| | - David S Waddell
- Department of Biology, University of North Florida, Jacksonville, Florida
| | - Sue C Bodine
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa
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18
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Bodine SC. Edward F. Adolph Distinguished Lecture. Skeletal muscle atrophy: Multiple pathways leading to a common outcome. J Appl Physiol (1985) 2020; 129:272-282. [PMID: 32644910 DOI: 10.1152/japplphysiol.00381.2020] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Skeletal muscle atrophy continues to be a serious consequence of many diseases and conditions for which there is no treatment. Our understanding of the mechanisms regulating skeletal muscle mass has improved considerably over the past two decades. For many years it was known that skeletal muscle atrophy resulted from an imbalance between protein synthesis and protein breakdown, with the net balance shifting toward protein breakdown. However, the molecular and cellular mechanisms underlying the increased breakdown of myofibrils was unknown. Over the past two decades, numerous reports have identified novel genes and signaling pathways that are upregulated and activated in response to stimuli such as disuse, inflammation, metabolic stress, starvation and others that induce muscle atrophy. This review summarizes the discovery efforts performed in the identification of several pathways involved in the regulation of skeletal muscle mass: the mammalian target of rapamycin (mTORC1) and the ubiquitin proteasome pathway and the E3 ligases, MuRF1 and MAFbx. While muscle atrophy is a common outcome of many diseases, it is doubtful that a single gene or pathway initiates or mediates the breakdown of myofibrils. Interestingly, however, is the observation that upregulation of the E3 ligases, MuRF1 and MAFbx, is a common feature of many divergent atrophy conditions. The challenge for the field of muscle biology is to understand how all of the various molecules, transcription factors, and signaling pathways interact to produce muscle atrophy and to identify the critical factors for intervention.
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Affiliation(s)
- Sue C Bodine
- Department of Internal Medicine/Endocrinology and Metabolism, University of Iowa Carver College of Medicine, Iowa City, Iowa
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19
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Cooper LM, West RC, Hayes CS, Waddell DS. Dual-specificity phosphatase 29 is induced during neurogenic skeletal muscle atrophy and attenuates glucocorticoid receptor activity in muscle cell culture. Am J Physiol Cell Physiol 2020; 319:C441-C454. [PMID: 32639872 DOI: 10.1152/ajpcell.00200.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Skeletal muscle atrophy is caused by a decrease in muscle size and strength and results from a range of physiological conditions, including denervation, immobilization, corticosteroid exposure and aging. Newly named dual-specificity phosphatase 29 (Dusp29) has been identified as a novel neurogenic atrophy-induced gene in skeletal muscle. Quantitative PCR analysis revealed that Dusp29 expression is significantly higher in differentiated myotubes compared with proliferating myoblasts. To determine how Dusp29 is transcriptionally regulated in skeletal muscle, fragments of the promoter region of Dusp29 were cloned, fused to a reporter gene, and found to be highly inducible in response to ectopic expression of the myogenic regulatory factors (MRF), MyoD and myogenin. Furthermore, site-directed mutagenesis of conserved E-box elements within the proximal promoter of Dusp29 rendered a Dusp29 reporter gene unresponsive to MRF overexpression. Dusp29, an atypical Dusp also known as Dupd1/Dusp27, was found to attenuate the ERK1/2 branch of the MAP kinase signaling pathway in muscle cells and inhibit muscle cell differentiation when ectopically expressed in proliferating myoblasts. Interestingly, Dusp29 was also found to destabilize AMPK protein while simultaneously enriching the phosphorylated pool of AMPK in muscle cells. Additionally, Dusp29 overexpression resulted in a significant increase in the glucocorticoid receptor (GR) protein and elevation in GR phosphorylation. Finally, Dusp29 was found to significantly impair the ability of the glucocorticoid receptor to function as a transcriptional activator in muscle cells treated with dexamethasone. Identifying and characterizing the function of Dusp29 in muscle provides novel insights into the molecular and cellular mechanisms for skeletal muscle atrophy.
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Affiliation(s)
- Lisa M Cooper
- Department of Biology, University of North Florida, Jacksonville, Florida
| | - Rita C West
- Department of Biology, University of North Florida, Jacksonville, Florida
| | - Caleb S Hayes
- Department of Biology, University of North Florida, Jacksonville, Florida
| | - David S Waddell
- Department of Biology, University of North Florida, Jacksonville, Florida
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20
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Differences in the Role of HDACs 4 and 5 in the Modulation of Processes Regulating MAFbx and MuRF1 Expression during Muscle Unloading. Int J Mol Sci 2020; 21:ijms21134815. [PMID: 32646070 PMCID: PMC7370043 DOI: 10.3390/ijms21134815] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/03/2020] [Accepted: 07/04/2020] [Indexed: 02/06/2023] Open
Abstract
Unloading leads to skeletal muscle atrophy via the upregulation of MuRF-1 and MAFbx E3-ligases expression. Reportedly, histone deacetylases (HDACs) 4 and 5 may regulate the expression of MuRF1 and MAFbx. To examine the HDAC-dependent mechanisms involved in the control of E3-ubiquitin ligases expression at the early stages of muscle unloading we used HDACs 4 and 5 inhibitor LMK-235 and HDAC 4 inhibitor Tasqinimod (Tq). Male Wistar rats were divided into four groups (eight rats per group): nontreated control (C), three days of unloading/hindlimb suspension (HS) and three days HS with HDACs inhibitor LMK-235 (HSLMK) or Tq (HSTq). Treatment with LMK-235 diminished unloading-induced of MAFbx, myogenin (MYOG), ubiquitin and calpain-1 mRNA expression (p < 0.05). Tq administration had no effect on the expression of E3-ligases. The mRNA expression of MuRF1 and MAFbx was significantly increased in both HS and HSTq groups (1.5 and 4.0 folds, respectively; p < 0.05) when compared with the C group. It is concluded that during three days of muscle unloading: (1) the HDACs 4 and 5 participate in the regulation of MAFbx expression as well as the expression of MYOG, ubiquitin and calpain-1; (2) the inhibition of HDAC 4 has no effect on MAFbx expression. Therefore, HDAC 5 is perhaps more important for the regulation of MAFbx expression than HDAC 4.
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21
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Cooper LM, Waddell DS. A tale of two DUSP27s: proposed resolution for the naming of distinct dual-specificity phosphatases. Am J Physiol Cell Physiol 2020; 319:C148-C150. [PMID: 32491926 DOI: 10.1152/ajpcell.00201.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Lisa M Cooper
- Department of Biology, University of North Florida, Jacksonville, Florida
| | - David S Waddell
- Department of Biology, University of North Florida, Jacksonville, Florida
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22
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Labuzan SA, Lynch SA, Cooper LM, Waddell DS. Inhibition of protein phosphatase methylesterase 1 dysregulates MAP kinase signaling and attenuates muscle cell differentiation. Gene 2020; 739:144515. [DOI: 10.1016/j.gene.2020.144515] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 02/24/2020] [Accepted: 02/25/2020] [Indexed: 02/07/2023]
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23
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Kawao N, Morita H, Iemura S, Ishida M, Kaji H. Roles of Dkk2 in the Linkage from Muscle to Bone during Mechanical Unloading in Mice. Int J Mol Sci 2020; 21:ijms21072547. [PMID: 32268570 PMCID: PMC7177709 DOI: 10.3390/ijms21072547] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 04/03/2020] [Accepted: 04/03/2020] [Indexed: 12/17/2022] Open
Abstract
Mechanical unloading simultaneously induces muscle and bone loss, but its mechanisms are not fully understood. The interactions between skeletal muscle and bone have been recently noted. Although canonical wingless-related integration site (Wnt)/β-catenin signaling is crucial for bone metabolism, its roles in the muscle and bone interactions have remained unknown. Here, we performed comprehensive DNA microarray analyses to clarify humoral factors linking muscle to bone in response to mechanical unloading and hypergravity with 3 g in mice. We identified Dickkopf (Dkk) 2, a Wnt/β-catenin signaling inhibitor, as a gene whose expression was increased by hindlimb unloading (HU) and reduced by hypergravity in the soleus muscle of mice. HU significantly elevated serum Dkk2 levels and Dkk2 mRNA levels in the soleus muscle of mice whereas hypergravity significantly decreased those Dkk2 levels. In the simple regression analyses, serum Dkk2 levels were negatively and positively related to trabecular bone mineral density and mRNA levels of receptor activator of nuclear factor-kappa B ligand (RANKL) in the tibia of mice, respectively. Moreover, shear stress significantly suppressed Dkk2 mRNA levels in C2C12 cells, and cyclooxygenase inhibitors significantly antagonized the effects of shear stress on Dkk2 expression. On the other hand, Dkk2 suppressed the mRNA levels of osteogenic genes, alkaline phosphatase activity and mineralization, and it increased RANKL mRNA levels in mouse osteoblasts. In conclusion, we showed that muscle and serum Dkk2 levels are positively and negatively regulated during mechanical unloading and hypergravity in mice, respectively. An increase in Dkk2 expression in the skeletal muscle might contribute to disuse- and microgravity-induced bone and muscle loss.
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Affiliation(s)
- Naoyuki Kawao
- Department of Physiology and Regenerative Medicine, Kindai University Faculty of Medicine, Osakasayama 589-8511, Japan; (N.K.); (S.I.); (M.I.)
| | - Hironobu Morita
- Department of Physiology, Gifu University Graduate School of Medicine, Gifu 501-1194, Japan;
| | - Shunki Iemura
- Department of Physiology and Regenerative Medicine, Kindai University Faculty of Medicine, Osakasayama 589-8511, Japan; (N.K.); (S.I.); (M.I.)
| | - Masayoshi Ishida
- Department of Physiology and Regenerative Medicine, Kindai University Faculty of Medicine, Osakasayama 589-8511, Japan; (N.K.); (S.I.); (M.I.)
| | - Hiroshi Kaji
- Department of Physiology and Regenerative Medicine, Kindai University Faculty of Medicine, Osakasayama 589-8511, Japan; (N.K.); (S.I.); (M.I.)
- Correspondence: ; Tel.: +81-72-366-0221
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24
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Cooper LM, Hanson A, Kavanagh JA, Waddell DS. Fam83d modulates MAP kinase and AKT signaling and is induced during neurogenic skeletal muscle atrophy. Cell Signal 2020; 70:109576. [PMID: 32092437 DOI: 10.1016/j.cellsig.2020.109576] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Revised: 02/20/2020] [Accepted: 02/20/2020] [Indexed: 01/08/2023]
Abstract
Skeletal muscle atrophy is a serious health condition that can arise due to aging, cancer, corticosteroid exposure, and denervation. Previous work comparing gene expression profiles in control and denervated muscle tissue revealed for the first time that Fam83d is expressed in skeletal muscle and is significantly induced in response to denervation. Quantitative PCR and Western blot analysis found that Fam83d is more highly expressed in proliferating myoblasts compared to differentiated myotubes. Characterization of the transcriptional regulation of Fam83d showed that ectopic expression of myogenic regulatory factors inhibits Fam83d reporter gene activity. To assess where Fam83d is localized in the cell, Fam83d was fused with green fluorescent protein, expressed in C2C12 cells, and found to localize in a punctate manner to the cytoplasm of muscle cells. To assess function, Fam83d was ectopically expressed in cultured muscle cells and markers of muscle cell differentiation, the MAP Kinase signaling pathway, and the AKT signaling pathway were analyzed. Fam83d overexpression resulted in significant repression of myosin heavy chain and myogenin expression, while phosphorylated ERK and AKT were also significantly repressed. Interestingly, inhibition of the 26S proteasome and the MAP kinase signaling pathway both resulted in stabilization of Fam83d during muscle cell differentiation. Finally, Fam83d has a putative phospholipase D-like domain that appears to be necessary for destabilizing casein kinase Iα and inhibiting ERK phosphorylation in cultured myoblasts. The discovery that Fam83d is expressed in skeletal muscle combined with the observation that Fam83d, a potential modulator of MAP kinase and AKT signaling, is induced in response to neurogenic atrophy helps further our understanding of the molecular and cellular events of skeletal muscle wasting.
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Affiliation(s)
- Lisa M Cooper
- University of North Florida, Department of Biology, 1 UNF Drive, Jacksonville, FL 32224, United States of America
| | - Abby Hanson
- University of North Florida, Department of Biology, 1 UNF Drive, Jacksonville, FL 32224, United States of America
| | - Jack A Kavanagh
- University of North Florida, Department of Biology, 1 UNF Drive, Jacksonville, FL 32224, United States of America
| | - David S Waddell
- University of North Florida, Department of Biology, 1 UNF Drive, Jacksonville, FL 32224, United States of America.
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Belova SP, Mochalova EP, Nemirovskaya TL. The Role of Class IIa HDACs in the Expression of E3 Ligases ATROGIN-1/MAFbx and MuRF1 under Muscle Unloading. BIOCHEMISTRY MOSCOW SUPPLEMENT SERIES A-MEMBRANE AND CELL BIOLOGY 2020. [DOI: 10.1134/s1990747820010031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Zhang Y, Li C, Yang Z. Is MYND Domain-Mediated Assembly of SMYD3 Complexes Involved in Calcium Dependent Signaling? Front Mol Biosci 2019; 6:121. [PMID: 31737645 PMCID: PMC6837996 DOI: 10.3389/fmolb.2019.00121] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 10/17/2019] [Indexed: 12/17/2022] Open
Abstract
Macromolecular complexes are essential to intracellular signal transduction by creating signaling niches and enabling a chain of reactions that transmit external signals into various cellular responses. Analysis of SMYD3 interactome indicates this protein lysine methyltransferase might be involved in calcium dependent signaling pathways through forming complexes with the phospholipase PLCB3, calcium/calmodulin dependent kinase CAMK2B, or calcineurin inhibitor RCAN3. SMYD3 is well-known as a histone H3K4 methyltransferase involved in epigenetic transcriptional regulation; however, any roles SMYD3 may play in signaling transduction remain unknown. KEGG pathway enrichment analysis reveals the SMYD3 interacting proteins are overrepresented in several signaling pathways such as estrogen signaling pathway, NOD-like receptor signaling pathway, and WNT signaling pathway. Sequence motif scanning reveals a significant enrichment of PXLXP motif in SMYD3 interacting proteins. The MYND domain of SMYD3 is known to bind to the PXLXP motif. The enrichment of the PXLXP motif suggests that the MYND domain is likely to be a key interaction module that mediates formation of some SMYD3 complexes. The presence of the PXLXP motifs in PLCB3 and CAMK2B indicates the potential role of the MYND domain in mediating complex formation in signaling. The structural basis of SMYD3 MYND domain-mediated interactions is unknown. The only available MYND-peptide complex structure suggests the MYND domain-mediated interaction is likely transient and dynamic. The transient nature will make this domain well-suited to mediate signaling transduction processes where it may allow rapid responses to cellular perturbations and changes in environment.
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Affiliation(s)
- Yingxue Zhang
- Department of Biochemistry, Microbiology, and Immunology, Wayne State University School of Medicine, Detroit, MI, United States
| | - Chunying Li
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, United States
| | - Zhe Yang
- Department of Biochemistry, Microbiology, and Immunology, Wayne State University School of Medicine, Detroit, MI, United States
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Yamada T, Ashida Y, Tatebayashi D, Himori K. Myofibrillar function differs markedly between denervated and dexamethasone-treated rat skeletal muscles: Role of mechanical load. PLoS One 2019; 14:e0223551. [PMID: 31596883 PMCID: PMC6785062 DOI: 10.1371/journal.pone.0223551] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 09/24/2019] [Indexed: 01/24/2023] Open
Abstract
Although there is good evidence to indicate a major role of intrinsic impairment of the contractile apparatus in muscle weakness seen in several pathophysiological conditions, the factors responsible for control of myofibrillar function are not fully understood. To investigate the role of mechanical load in myofibrillar function, we compared the skinned fiber force between denervated (DEN) and dexamethasone-treated (DEX) rat skeletal muscles with or without neuromuscular electrical stimulation (ES) training. DEN and DEX were induced by cutting the sciatic nerve and daily injection of dexamethasone (5 mg/kg/day) for 7 days, respectively. For ES training, plantarflexor muscles were electrically stimulated to produce four sets of five isometric contractions each day. In situ maximum torque was markedly depressed in the DEN muscles compared to the DEX muscles (-74% vs. -10%), whereas there was not much difference in the degree of atrophy in gastrocnemius muscles between DEN and DEX groups (-24% vs. -17%). Similar results were obtained in the skinned fiber preparation, with a greater reduction in maximum Ca2+-activated force in the DEN than in the DEX group (-53% vs. -16%). Moreover, there was a parallel decline in myosin heavy chain (MyHC) and actin content per muscle volume in DEN muscles, but not in DEX muscles, which was associated with upregulation of NADPH oxidase (NOX) 2, neuronal nitric oxide synthase (nNOS), and endothelial NOS expression, translocation of nNOS from the membrane to the cytosol, and augmentation of mRNA levels of muscle RING finger protein 1 (MuRF-1) and atrogin-1. Importantly, mechanical load evoked by ES protects against DEN- and DEX-induced myofibrillar dysfunction and these molecular alterations. Our findings provide novel insights regarding the difference in intrinsic contractile properties between DEN and DEX and suggest an important role of mechanical load in preserving myofibrillar function in skeletal muscle.
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Affiliation(s)
- Takashi Yamada
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
- * E-mail:
| | - Yuki Ashida
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
- Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan
| | - Daisuke Tatebayashi
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Koichi Himori
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
- Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan
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Zinc finger protein 593 is upregulated during skeletal muscle atrophy and modulates muscle cell differentiation. Exp Cell Res 2019; 383:111563. [PMID: 31442450 DOI: 10.1016/j.yexcr.2019.111563] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 08/14/2019] [Accepted: 08/17/2019] [Indexed: 12/14/2022]
Abstract
Skeletal muscle atrophy is a debilitating condition that can arise due to aging, cancer, corticosteroid use, and denervation. To better characterize the molecular genetic events of neurogenic atrophy, a previous study analyzed gene expression patterns in gastrocnemius muscle following sciatic nerve transection and found for the first time that Zinc Finger Protein 593 (Zfp593) is expressed in skeletal muscle and is induced in response to denervation. Quantitative PCR and Western blot analyses confirmed that Zfp593 is expressed in both proliferating myoblasts and differentiated myotubes. To assess sub-cellular location, GFP-tagged Zfp593 was expressed in C2C12 cells and found to localize to the nucleus. The Zfp593 protein possesses a putative zinc finger domain and is believed to function as a modulator of the Oct-2 transcription factor. Interestingly, ectopic expression of Zfp593 did not affect the ability of Oct-1 or Oct-2 to inhibit an Oct reporter gene in muscle cells. Finally, Zfp593 overexpression in cultured muscle cells resulted in significant repression of muscle cell differentiation and attenuation of ERK1/2 and p38 phosphorylation, but did not vitiate protein synthesis. The discovery that Zfp593 is expressed in skeletal muscle combined with the observation that it is induced in response to neurogenic atrophy furthers our understanding of the molecular genetic events of muscle wasting.
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Gergs U, Jahn T, Werner F, Köhler C, Köpp F, Großmann C, Neumann J. Overexpression of protein phosphatase 5 in the mouse heart: Reduced contractility but increased stress tolerance - Two sides of the same coin? PLoS One 2019; 14:e0221289. [PMID: 31425567 PMCID: PMC6699691 DOI: 10.1371/journal.pone.0221289] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 08/02/2019] [Indexed: 11/18/2022] Open
Abstract
The pathophysiological mechanisms of sepsis-induced cardiac dysfunction are largely unknown. The Toll-like receptor 4 (TLR4) is expressed in cardiac myocytes and is involved in bacterial endotoxin-mediated inflammatory disorders. TLR4 signaling leads to activation of the nuclear factor kappa B followed by increased expression of cytokines. Several protein phosphatases including PP2Cβ, PP2A or PP1 are known to act as regulators of this signaling pathway. Here, we examined the role of PP5 for the inflammatory response to the bacterial endotoxin lipopolysaccharide in the heart using a transgenic mouse model with cardiac myocyte directed overexpression of PP5. In these transgenic mice, basal cardiac contractility was reduced, in vivo as well as in vitro, but LPS-induced cardiac dysfunction was less pronounced compared to wild type mice. Quantitative RT-PCR suggested an attenuated NF-κB signaling in the heart and cardiac expression of heat shock protein 25 (HSP25) was increased in PP5 transgenic mice. From our data we assume that PP5 increases stress tolerance of cardiac myocytes by downregulation of NF-κB signaling and upregulation of HSP25 expression.
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Affiliation(s)
- Ulrich Gergs
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
- * E-mail:
| | - Tina Jahn
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
| | - Franziska Werner
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
| | - Carolin Köhler
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
| | - Friedrich Köpp
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
| | - Claudia Großmann
- Julius-Bernstein-Institut für Physiologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
| | - Joachim Neumann
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
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Hayes CS, Labuzan SA, Menke JA, Haddock AN, Waddell DS. Ttc39c is upregulated during skeletal muscle atrophy and modulates ERK1/2 MAP kinase and hedgehog signaling. J Cell Physiol 2019; 234:23807-23824. [DOI: 10.1002/jcp.28950] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 05/15/2019] [Accepted: 05/20/2019] [Indexed: 12/19/2022]
Affiliation(s)
- Caleb S. Hayes
- Department of Biology University of North Florida Jacksonville Florida
| | - Sydney A. Labuzan
- Department of Biology University of North Florida Jacksonville Florida
| | - Jacob A. Menke
- Department of Biology University of North Florida Jacksonville Florida
| | - Ashley N. Haddock
- Department of Biology University of North Florida Jacksonville Florida
| | - David S. Waddell
- Department of Biology University of North Florida Jacksonville Florida
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Gordon BS, Rossetti ML, Eroshkin AM. Arrdc2 and Arrdc3 elicit divergent changes in gene expression in skeletal muscle following anabolic and catabolic stimuli. Physiol Genomics 2019; 51:208-217. [DOI: 10.1152/physiolgenomics.00007.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Skeletal muscle is a highly plastic organ regulating various processes in the body. As such, loss of skeletal muscle underlies the increased morbidity and mortality risk that is associated with numerous conditions. However, no therapies are available to combat the loss of muscle mass during atrophic conditions, which is due in part to the incomplete understanding of the molecular networks altered by anabolic and catabolic stimuli. Thus, the current objective was to identify novel gene networks modulated by such stimuli. For this, total RNA from the tibialis anterior muscle of mice that were fasted overnight or fasted overnight and refed the next morning was subjected to microarray analysis. The refeeding stimulus altered the expression of genes associated with signal transduction. Specifically, expression of alpha arrestin domain containing 2 (Arrdc2) and alpha arrestin domain containing 3 (Arrdc3) was significantly lowered 70–85% by refeeding. Subsequent analysis showed that expression of these genes was also lowered 50–75% by mechanical overload, with the combination of nutrients and mechanical overload acting synergistically to lower Arrdc2 and Arrdc3 expression. On the converse, stimuli that suppress growth such as testosterone depletion or acute aerobic exercise increased Arrdc2 and Arrdc3 expression in skeletal muscle. While Arrdc2 and Arrdc3 exhibited divergent changes in expression following anabolic or catabolic stimuli, no other member of the Arrdc family of genes exhibited the consistent change in expression across the analyzed conditions. Thus, Arrdc2 and Arrdc3 are a novel set of genes that may be implicated in the regulation of skeletal muscle mass.
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Affiliation(s)
- Bradley S. Gordon
- Department of Nutrition, Food & Exercise Sciences, Florida State University, Tallahassee, Florida
- Institute of Sports Sciences and Medicine, Florida State University, Tallahassee, Florida
| | - Michael L. Rossetti
- Department of Nutrition, Food & Exercise Sciences, Florida State University, Tallahassee, Florida
| | - Alexey M. Eroshkin
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California
- Rancho BioSciences, San Diego, California
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Haddock AN, Labuzan SA, Haynes AE, Hayes CS, Kakareka KM, Waddell DS. Dual-specificity phosphatase 4 is upregulated during skeletal muscle atrophy and modulates extracellular signal-regulated kinase activity. Am J Physiol Cell Physiol 2019; 316:C567-C581. [DOI: 10.1152/ajpcell.00234.2018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Skeletal muscle atrophy results from disparate physiological conditions, including denervation, corticosteroid treatment, and aging. The purpose of this study was to describe and characterize the function of dual-specificity phosphatase 4 (Dusp4) in skeletal muscle after it was found to be induced in response to neurogenic atrophy. Quantitative PCR and Western blot analysis revealed that Dusp4 is expressed during myoblast proliferation but rapidly disappears as muscle cells differentiate. The Dusp4 regulatory region was cloned and found to contain a conserved E-box element that negatively regulates Dusp4 reporter gene activity in response to myogenic regulatory factor expression. In addition, the proximal 3′-untranslated region of Dusp4 acts in an inhibitory manner to repress reporter gene activity as muscle cells progress through the differentiation process. To determine potential function, Dusp4 was fused with green fluorescent protein, expressed in C2C12 cells, and found to localize to the nucleus of proliferating myoblasts. Furthermore, Dusp4 overexpression delayed C2C12 muscle cell differentiation and resulted in repression of a MAP kinase signaling pathway reporter gene. Ectopic expression of a Dusp4 dominant negative mutant blocked muscle cell differentiation and attenuated MAP kinase signaling by preferentially targeting the ERK1/2 branch, but not the p38 branch, of the MAP kinase signaling cascade in skeletal muscle cells. The findings presented in this study provide the first description of Dusp4 in skeletal muscle and suggest that Dusp4 may play an important role in the regulation of muscle cell differentiation by regulating MAP kinase signaling.
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Affiliation(s)
- Ashley N. Haddock
- Department of Biology, University of North Florida, Jacksonville, Florida
| | - Sydney A. Labuzan
- Department of Biology, University of North Florida, Jacksonville, Florida
| | - Amy E. Haynes
- Department of Biology, University of North Florida, Jacksonville, Florida
| | - Caleb S. Hayes
- Department of Biology, University of North Florida, Jacksonville, Florida
| | - Karina M. Kakareka
- Department of Biology, University of North Florida, Jacksonville, Florida
| | - David S. Waddell
- Department of Biology, University of North Florida, Jacksonville, Florida
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Rodrigues ACZ, Messi ML, Wang ZM, Abba MC, Pereyra A, Birbrair A, Zhang T, O’Meara M, Kwan P, Lopez EIS, Willis MS, Mintz A, Files DC, Furdui C, Oppenheim RW, Delbono O. The sympathetic nervous system regulates skeletal muscle motor innervation and acetylcholine receptor stability. Acta Physiol (Oxf) 2019; 225:e13195. [PMID: 30269419 PMCID: PMC7224611 DOI: 10.1111/apha.13195] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 09/23/2018] [Accepted: 09/26/2018] [Indexed: 12/19/2022]
Abstract
AIM Symptoms of autonomic failure are frequently the presentation of advanced age and neurodegenerative diseases that impair adaptation to common physiologic stressors. The aim of this work was to examine the interaction between the sympathetic and motor nervous system, the involvement of the sympathetic nervous system (SNS) in neuromuscular junction (NMJ) presynaptic motor function, the stability of postsynaptic molecular organization, and the skeletal muscle composition and function. METHODS Since muscle weakness is a symptom of diseases characterized by autonomic dysfunction, we studied the impact of regional sympathetic ablation on muscle motor innervation by using transcriptome analysis, retrograde tracing of the sympathetic outflow to the skeletal muscle, confocal and electron microscopy, NMJ transmission by electrophysiological methods, protein analysis, and state of the art microsurgical techniques, in C57BL6, MuRF1KO and Thy-1 mice. RESULTS We found that the SNS regulates motor nerve synaptic vesicle release, skeletal muscle transcriptome, muscle force generated by motor nerve activity, axonal neurofilament phosphorylation, myelin thickness, and myofibre subtype composition and CSA. The SNS also modulates the levels of postsynaptic membrane acetylcholine receptor by regulating the Gαi2 -Hdac4-Myogenin-MuRF1pathway, which is prevented by the overexpression of the guanine nucleotide-binding protein Gαi2 (Q205L), a constitutively active mutant G protein subunit. CONCLUSION The SNS regulates NMJ transmission, maintains optimal Gαi2 expression, and prevents any increase in Hdac4, myogenin, MuRF1, and miR-206. SNS ablation leads to upregulation of MuRF1, muscle atrophy, and downregulation of postsynaptic AChR. Our findings are relevant to clinical conditions characterized by progressive decline of sympathetic innervation, such as neurodegenerative diseases and aging.
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Affiliation(s)
- Anna C. Z. Rodrigues
- Department of Internal Medicine, Gerontology, Wake Forest School of Medicine, Winston-Salem, North Carolina
- Neuroscience Program, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Maria L. Messi
- Department of Internal Medicine, Gerontology, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Zhong-Min Wang
- Department of Internal Medicine, Gerontology, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Martin C. Abba
- Basic and Applied Immunological Research Center (CINIBA), School of Medicine, National University of La Plata, Buenos Aires, Argentina
| | - Andrea Pereyra
- Department of Internal Medicine, Gerontology, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Alexander Birbrair
- Department of Internal Medicine, Gerontology, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Tan Zhang
- Department of Internal Medicine, Gerontology, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Meaghan O’Meara
- Department of Internal Medicine, Gerontology, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Ping Kwan
- Department of Internal Medicine, Gerontology, Wake Forest School of Medicine, Winston-Salem, North Carolina
- Neuroscience Program, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Elsa I. S. Lopez
- Department of Internal Medicine, Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Monte S. Willis
- Department of Pathology, McAllister Heart Institute, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina
| | - Akiva Mintz
- Department of Radiology, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - D. Clark Files
- Department of Internal Medicine, Gerontology, Wake Forest School of Medicine, Winston-Salem, North Carolina
- Department of Internal Medicine, Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina
- Department of Internal Medicine, Pulmonary, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Cristina Furdui
- Department of Internal Medicine, Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Ronald W. Oppenheim
- Department of Neurobiology and Anatomy, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Osvaldo Delbono
- Department of Internal Medicine, Gerontology, Wake Forest School of Medicine, Winston-Salem, North Carolina
- Neuroscience Program, Wake Forest School of Medicine, Winston-Salem, North Carolina
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Brown JL, Lee DE, Rosa-Caldwell ME, Brown LA, Perry RA, Haynie WS, Huseman K, Sataranatarajan K, Van Remmen H, Washington TA, Wiggs MP, Greene NP. Protein imbalance in the development of skeletal muscle wasting in tumour-bearing mice. J Cachexia Sarcopenia Muscle 2018; 9:987-1002. [PMID: 30328290 PMCID: PMC6204589 DOI: 10.1002/jcsm.12354] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Accepted: 08/28/2018] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Cancer cachexia occurs in approximately 80% of cancer patients and is a key contributor to cancer-related death. The mechanisms controlling development of tumour-induced muscle wasting are not fully elucidated. Specifically, the progression and development of cancer cachexia are underexplored. Therefore, we examined skeletal muscle protein turnover throughout the development of cancer cachexia in tumour-bearing mice. METHODS Lewis lung carcinoma (LLC) was injected into the hind flank of C57BL6/J mice at 8 weeks age with tumour allowed to develop for 1, 2, 3, or 4 weeks and compared with PBS injected control. Muscle size was measured by cross-sectional area analysis of haematoxylin and eosin stained tibialis anterior muscle. 2 H2 O was used to assess protein synthesis throughout the development of cancer cachexia. Immunoblot and RT-qPCR were used to measure regulators of protein turnover. TUNEL staining was utilized to measure apoptotic nuclei. LLC conditioned media (LCM) treatment of C2C12 myotubes was used to analyse cancer cachexia in vitro. RESULTS Muscle cross-sectional area decreased ~40% 4 weeks following tumour implantation. Myogenic signalling was suppressed in tumour-bearing mice as soon as 1 week following tumour implantation, including lower mRNA contents of Pax7, MyoD, CyclinD1, and Myogenin, when compared with control animals. AchRδ and AchRε mRNA contents were down-regulated by ~50% 3 weeks following tumour implantation. Mixed fractional synthesis rate protein synthesis was ~40% lower in 4 week tumour-bearing mice when compared with PBS controls. Protein ubiquitination was elevated by ~50% 4 weeks after tumour implantation. Moreover, there was an increase in autophagy machinery after 4 weeks of tumour growth. Finally, ERK and p38 MAPK phosphorylations were fourfold and threefold greater than control muscle 4 weeks following tumour implantation, respectively. Inhibition of p38 MAPK, but not ERK MAPK, in vitro partially rescued LCM-induced loss of myotube diameter. CONCLUSIONS Our findings work towards understanding the pathophysiological signalling in skeletal muscle in the initial development of cancer cachexia. Shortly following the onset of the tumour-bearing state alterations in myogenic regulatory factors are apparent, suggesting early onset alterations in the capacity for myogenic induction. Cancer cachexia presents with a combination of a loss of protein synthesis and increased markers of protein breakdown, specifically in the ubiquitin-proteasome system. Also, p38 MAPK may be a potential therapeutic target to combat cancer cachexia via a p38-FOX01-atrogene-ubiquitin-proteasome mechanism.
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Affiliation(s)
- Jacob L Brown
- Integrative Muscle Metabolism Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, 72701, USA
| | - David E Lee
- Integrative Muscle Metabolism Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, 72701, USA
| | - Megan E Rosa-Caldwell
- Integrative Muscle Metabolism Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, 72701, USA
| | - Lemuel A Brown
- Exercise Muscle Biology Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, 72701, USA.,Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Richard A Perry
- Exercise Muscle Biology Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, 72701, USA
| | - Wesley S Haynie
- Exercise Muscle Biology Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, 72701, USA
| | - Kendra Huseman
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 N.E. 13th Street, Oklahoma City, OK, 73104, USA
| | - Kavithalakshmi Sataranatarajan
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 N.E. 13th Street, Oklahoma City, OK, 73104, USA
| | - Holly Van Remmen
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 N.E. 13th Street, Oklahoma City, OK, 73104, USA.,Oklahoma City VA Medical Center, Oklahoma City, OK, USA
| | - Tyrone A Washington
- Exercise Muscle Biology Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, 72701, USA
| | - Michael P Wiggs
- Integrated Physiology and Nutrition Laboratory, Department of Health and Kinesiology, University of Texas at Tyler, Tyler, TX, 75799, USA
| | - Nicholas P Greene
- Integrative Muscle Metabolism Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, 72701, USA
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Cho Y, Ross RS. A mini review: Proteomics approaches to understand disused vs. exercised human skeletal muscle. Physiol Genomics 2018; 50:746-757. [PMID: 29958080 DOI: 10.1152/physiolgenomics.00043.2018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Immobilization, bed rest, or denervation leads to muscle disuse and subsequent skeletal muscle atrophy. Muscle atrophy can also occur as a component of various chronic diseases such as cancer, AIDS, sepsis, diabetes, and chronic heart failure or as a direct result of genetic muscle disorders. In addition to this atrophic loss of muscle mass, metabolic deregulation of muscle also occurs. In contrast, physical exercise plays a beneficial role in counteracting disuse-induced atrophy by increasing muscle mass and strength. Along with this, exercise can also reduce mitochondrial dysfunction and metabolic deregulation. Still, while exercise causes valuable metabolic and functional adaptations in skeletal muscle, the mechanisms and effectors that lead to these changes such as increased mitochondria content or enhanced protein synthesis are not fully understood. Therefore, mechanistic insights may ultimately provide novel ways to treat disuse induced atrophy and metabolic deregulation. Mass spectrometry (MS)-based proteomics offers enormous promise for investigating the molecular mechanisms underlying disuse and exercise-induced changes in skeletal muscle. This review will focus on initial findings uncovered by using proteomics approaches with human skeletal muscle specimens and discuss their potential for the future study.
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Affiliation(s)
- Yoshitake Cho
- Division of Cardiology, Department of Medicine, University of California San Diego , La Jolla, California
| | - Robert S Ross
- Division of Cardiology, Department of Medicine, University of California San Diego , La Jolla, California.,Cardiology Section, Department of Medicine, Veterans Administration Healthcare , San Diego, California
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36
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Gonzalez-Freire M, Adelnia F, Moaddel R, Ferrucci L. Searching for a mitochondrial root to the decline in muscle function with ageing. J Cachexia Sarcopenia Muscle 2018; 9:435-440. [PMID: 29774990 PMCID: PMC5989834 DOI: 10.1002/jcsm.12313] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 04/25/2018] [Indexed: 12/14/2022] Open
Abstract
Sarcopenia, the age-related loss of muscle mass and strength, is linked to a range of adverse outcomes, such as impaired physical performance, cognitive function, and mortality. Preventing sarcopenia may reduce the burden of functional decline with aging and its impact on physiological and economic well-being in older adults. Mitochondria in muscle cells lose their intrinsic efficiency and capacity to produce energy during aging, and it has been hypothesized that such a decline is the main driver of sarcopenia. Oxidative phosphorylation becomes impaired with aging, affecting muscle performance, and contributing to an age-associated decline in mobility. However, it is unclear whether this deterioration is due to a reduced mitochondria population, decreased mitochondrial energetic efficiency, or a reduced capacity to dynamically transport oxygen and nutrients into the mitochondria, and addressing these questions is an active area of research. Further research in humans will require use of new "omics" technologies, progress in neuroimaging techniques that permit energy production assessment, and visualization of molecules critical for energetic metabolism, as well as proxy biomarkers of muscle perfusion.
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Affiliation(s)
- Marta Gonzalez-Freire
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Fatemeh Adelnia
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Ruin Moaddel
- Diabetes Section, Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Luigi Ferrucci
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
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Abstract
Glucocorticoids (GC), produced and released by the adrenal glands, regulate numerous physiological processes in a wide range of tissues. Because of their profound immunosuppressive and anti-inflammatory actions, GC are extensively used for the treatment of immune and inflammatory conditions, the management of organ transplantation, and as a component of chemotherapy regimens for cancers. However, both pathologic endogenous elevation and long-term use of exogenous GC are associated with severe adverse effects. In particular, excess GC has devastating effects on the musculoskeletal system. GC increase bone resorption and decrease formation leading to bone loss, microarchitectural deterioration and fracture. GC also induce loss of muscle mass and strength leading to an increased incidence of falls. The combined effects on bone and muscle account for the increased fracture risk with GC. This review summarizes the advance in knowledge in the last two decades about the mechanisms of action of GC in bone and muscle and the attempts to interfere with the damaging actions of GC in these tissues with the goal of developing more effective therapeutic strategies.
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Affiliation(s)
- Amy Y Sato
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, 46202
| | - Munro Peacock
- Department of Medicine, Division of Endocrinology, Indiana University School of Medicine, Indianapolis, Indiana, 46202
| | - Teresita Bellido
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, 46202.,Department of Medicine, Division of Endocrinology, Indiana University School of Medicine, Indianapolis, Indiana, 46202.,Roudebush Veterans Administration Medical Center, Indianapolis, Indiana, 46202
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Sato AY, Richardson D, Cregor M, Davis HM, Au ED, McAndrews K, Zimmers TA, Organ JM, Peacock M, Plotkin LI, Bellido T. Glucocorticoids Induce Bone and Muscle Atrophy by Tissue-Specific Mechanisms Upstream of E3 Ubiquitin Ligases. Endocrinology 2017; 158:664-677. [PMID: 28359087 PMCID: PMC5460781 DOI: 10.1210/en.2016-1779] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 01/03/2017] [Indexed: 11/19/2022]
Abstract
Glucocorticoid excess, either endogenous with diseases of the adrenal gland, stress, or aging or when administered for immunosuppression, induces bone and muscle loss, leading to osteopenia and sarcopenia. Muscle weakness increases the propensity for falling, which, combined with the lower bone mass, increases the fracture risk. The mechanisms underlying glucocorticoid-induced bone and muscle atrophy are not completely understood. We have demonstrated that the loss of bone and muscle mass, decreased bone formation, and reduced muscle strength, hallmarks of glucocorticoid excess, are accompanied by upregulation in both tissues in vivo of the atrophy-related genes atrogin1, MuRF1, and MUSA1. These are E3 ubiquitin ligases traditionally considered muscle-specific. Glucocorticoids also upregulated atrophy genes in cultured osteoblastic/osteocytic cells, in ex vivo bone organ cultures, and in muscle organ cultures and C2C12 myoblasts/myotubes. Furthermore, glucocorticoids markedly increased the expression of components of the Notch signaling pathway in muscle in vivo, ex vivo, and in vitro. In contrast, glucocorticoids did not increase Notch signaling in bone or bone cells. Moreover, the increased expression of atrophy-related genes in muscle, but not in bone, and the decreased myotube diameter induced by glucocorticoids were prevented by inhibiting Notch signaling. Thus, glucocorticoids activate different mechanisms in bone and muscle that upregulate atrophy-related genes. However, the role of these genes in the effects of glucocorticoids in bone is unknown. Nevertheless, these findings advance our knowledge of the mechanism of action of glucocorticoids in the musculoskeletal system and provide the basis for novel therapies to prevent glucocorticoid-induced atrophy of bone and muscle.
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Affiliation(s)
- Amy Y. Sato
- Department of Anatomy and Cell Biology
- Indiana Center for Musculoskeletal Health, Indianapolis, Indiana 46202
| | | | | | - Hannah M. Davis
- Department of Anatomy and Cell Biology
- Indiana Center for Musculoskeletal Health, Indianapolis, Indiana 46202
| | - Ernie D. Au
- Department of Surgery, Indiana University School of Medicine, Indianapolis, Indiana 46202
- Indiana Center for Musculoskeletal Health, Indianapolis, Indiana 46202
| | - Kevin McAndrews
- Department of Anatomy and Cell Biology
- Roudebush Veterans Affairs Medical Center, Indianapolis, Indiana 46202
| | - Teresa A. Zimmers
- Department of Anatomy and Cell Biology
- Department of Surgery, Indiana University School of Medicine, Indianapolis, Indiana 46202
- Roudebush Veterans Affairs Medical Center, Indianapolis, Indiana 46202
- Indiana Center for Musculoskeletal Health, Indianapolis, Indiana 46202
| | - Jason M. Organ
- Department of Anatomy and Cell Biology
- Department of Biomedical Engineering, Indiana University–Purdue University, Indianapolis, Indiana 46202; and
- Indiana Center for Musculoskeletal Health, Indianapolis, Indiana 46202
| | - Munro Peacock
- Department of Medicine, Division of Endocrinology, and
- Indiana Center for Musculoskeletal Health, Indianapolis, Indiana 46202
| | - Lilian I. Plotkin
- Department of Anatomy and Cell Biology
- Roudebush Veterans Affairs Medical Center, Indianapolis, Indiana 46202
- Indiana Center for Musculoskeletal Health, Indianapolis, Indiana 46202
| | - Teresita Bellido
- Department of Anatomy and Cell Biology
- Department of Medicine, Division of Endocrinology, and
- Roudebush Veterans Affairs Medical Center, Indianapolis, Indiana 46202
- Indiana Center for Musculoskeletal Health, Indianapolis, Indiana 46202
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39
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Lin XY, Chen SZ. Calpain inhibitors ameliorate muscle wasting in a cachectic mouse model bearing CT26 colorectal adenocarcinoma. Oncol Rep 2017; 37:1601-1610. [PMID: 28112357 DOI: 10.3892/or.2017.5396] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2016] [Accepted: 01/05/2017] [Indexed: 11/06/2022] Open
Abstract
Cancer-related cachexia involves increased protein breakdown through various proteolytic pathways, including the ubiquitin-proteasome pathway (UPP). We hypothesized that a calcium- and calpain-dependent pathway might play a crucial role during the proteolytic procedure, and that pathway interventions would ameliorate cancer cachexia in vivo. After being inoculated with CT26 adenocarcinoma cell culture subcutaneously, BALB/c mice developed cachexia in 12 days. They were then administered with different types of calpain inhibitors individually or in combination for 7 consecutive days. Eighteen healthy mice were also assessed as a control group. Changes in body weight, gastrocnemius muscle mass, tumor volume, food intake, survival time, and serum nutritional markers were monitored. Also measured were the levels of calpains, E3 ubiquitin ligases, and apoptosis-associated markers in gastrocnemius muscle. Our study showed that the intraperitoneal administration of calpain inhibitors significantly improved tumor-free body weight and gastrocnemius muscle mass in all treatment groups. Treatment with calpain inhibitors also ameliorated cachexia-associated negative effects in metabolic profiles and increased survival time in most of the tumor-bearing mice compared with the cachexia controls. Furthermore, calpain inhibitors reduced the calpain activity and the expression of MuRF-1 and atrogin-1 in all treatment groups, while increasing the level of cleaved caspase-3 and BAX and lowering the level of BCL-2 in some groups. These results justify further evaluation of calpain inhibitors both alone and in combination with other candidate agents as a potential new therapeutic strategy for treating cancer cachexia.
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Affiliation(s)
- Xing-Yu Lin
- The First Clinical Medical College of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Si-Zeng Chen
- The First Clinical Medical College of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
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40
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Gigliotti D, Xu MC, Davidson MJ, Macdonald PB, Leiter JRS, Anderson JE. Fibrosis, low vascularity, and fewer slow fibers after rotator-cuff injury. Muscle Nerve 2017; 55:715-726. [PMID: 27571286 DOI: 10.1002/mus.25388] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 08/15/2016] [Accepted: 08/23/2016] [Indexed: 01/08/2023]
Abstract
INTRODUCTION Rotator-cuff injury (RCI) represents 50% of shoulder injuries, and prevalence increases with age. Even with successful tendon repair, muscle and joint function may not return. METHODS To explore the dysfunction, supraspinatus and ipsilateral deltoid (control) muscles were biopsied during arthroscopic RCI repair for pair-wise histological and protein-expression studies. RESULTS Supraspinatus showed fiber atrophy (P < 0.0001), fibrosis (by Sirius Red, P = 0.05), reduced vascular density (P < 0.001), and a lower proportion of slow fibers (P < 0.0001) compared with the ipsilateral control muscle. There were also higher levels of atrogin-1 (P = 0.05), vascular endothelial growth factor (VEGF, P < 0.01), and dystrophin (P < 0.008, relative to fiber diameter) versus control. CONCLUSIONS Adaptive changes in vascular endothelial growth factor and dystrophin were likely associated with reduced vascular supply, fatigue resistance, and fibrosis, accompanied by disuse atrophy from mechanical unloading of supraspinatus after tendon tear. Treatment to promote growth and vascularity in atrophic supraspinatus muscle may help improve functional outcome after surgical repair. Muscle Nerve 55: 715-726, 2017.
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Affiliation(s)
- Deanna Gigliotti
- Department of Biological Sciences, Faculty of Science, University of Manitoba, 212 Biological Sciences Building, 50 Sifton Road, Winnipeg, MB, R3T 2N2, Canada
| | - Mark C Xu
- Faculty of Health Sciences College of Medicine Departments of Surgery (Orthopedics) at the University of Manitoba, Winnipeg, Canada
| | - Michael J Davidson
- Faculty of Health Sciences College of Medicine Department of Radiology at the University of Manitoba, Winnipeg, Canada
| | - Peter B Macdonald
- Faculty of Health Sciences College of Medicine Departments of Surgery (Orthopedics) at the University of Manitoba, Winnipeg, Canada.,Pan Am Clinic, Winnipeg, Canada
| | - Jeff R S Leiter
- Faculty of Health Sciences College of Medicine Departments of Surgery (Orthopedics) at the University of Manitoba, Winnipeg, Canada.,Pan Am Clinic, Winnipeg, Canada
| | - Judy E Anderson
- Department of Biological Sciences, Faculty of Science, University of Manitoba, 212 Biological Sciences Building, 50 Sifton Road, Winnipeg, MB, R3T 2N2, Canada
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41
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HUANG J, ZHU X. The Molecular Mechanisms of Calpains Action on Skeletal Muscle Atrophy. Physiol Res 2016; 65:547-560. [DOI: 10.33549/physiolres.933087] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Skeletal muscle atrophy is associated with a loss of muscle protein which may result from both increased proteolysis and decreased protein synthesis. Investigations on cell signaling pathways that regulate muscle atrophy have promoted our understanding of this complicated process. Emerging evidence implicates that calpains play key roles in dysregulation of proteolysis seen in muscle atrophy. Moreover, studies have also shown that abnormally activated calpain results muscle atrophy via its downstream effects on ubiquitin-proteasome pathway (UPP) and Akt phosphorylation. This review will discuss the role of calpains in regulation of skeletal muscle atrophy mainly focusing on its collaboration with either UPP or Akt in atrophy conditions in hope to stimulate the interest in development of novel therapeutic interventions for skeletal muscle atrophy.
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Affiliation(s)
| | - X. ZHU
- Department of Respiratory Diseases, YangPu Hospital of Tongji University, Shanghai, China
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42
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Isolation, expression analysis and characterization of NEFA-interacting nuclear protein 30 and RING finger and SPRY domain containing 1 in skeletal muscle. Gene 2016; 576:319-32. [DOI: 10.1016/j.gene.2015.10.046] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 10/07/2015] [Accepted: 10/16/2015] [Indexed: 11/18/2022]
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43
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Bodine SC, Furlow JD. Glucocorticoids and Skeletal Muscle. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015. [PMID: 26215994 DOI: 10.1007/978-1-4939-2895-8_7] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Glucocorticoids are known to regulate protein metabolism in skeletal muscle, producing a catabolic effect that is opposite that of insulin. In many catabolic diseases, such as sepsis, starvation, and cancer cachexia, endogenous glucocorticoids are elevated contributing to the loss of muscle mass and function. Further, exogenous glucocorticoids are often given acutely and chronically to treat inflammatory conditions such as asthma, chronic obstructive pulmonary disease, and rheumatoid arthritis, resulting in muscle atrophy. This chapter will detail the nature of glucocorticoid-induced muscle atrophy and discuss the mechanisms thought to be responsible for the catabolic effects of glucocorticoids on muscle.
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Affiliation(s)
- Sue C Bodine
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, One Shields Avenue, Davis, CA, 95616, USA,
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44
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Tintignac LA, Brenner HR, Rüegg MA. Mechanisms Regulating Neuromuscular Junction Development and Function and Causes of Muscle Wasting. Physiol Rev 2015; 95:809-52. [DOI: 10.1152/physrev.00033.2014] [Citation(s) in RCA: 224] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The neuromuscular junction is the chemical synapse between motor neurons and skeletal muscle fibers. It is designed to reliably convert the action potential from the presynaptic motor neuron into the contraction of the postsynaptic muscle fiber. Diseases that affect the neuromuscular junction may cause failure of this conversion and result in loss of ambulation and respiration. The loss of motor input also causes muscle wasting as muscle mass is constantly adapted to contractile needs by the balancing of protein synthesis and protein degradation. Finally, neuromuscular activity and muscle mass have a major impact on metabolic properties of the organisms. This review discusses the mechanisms involved in the development and maintenance of the neuromuscular junction, the consequences of and the mechanisms involved in its dysfunction, and its role in maintaining muscle mass during aging. As life expectancy is increasing, loss of muscle mass during aging, called sarcopenia, has emerged as a field of high medical need. Interestingly, aging is also accompanied by structural changes at the neuromuscular junction, suggesting that the mechanisms involved in neuromuscular junction maintenance might be disturbed during aging. In addition, there is now evidence that behavioral paradigms and signaling pathways that are involved in longevity also affect neuromuscular junction stability and sarcopenia.
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Affiliation(s)
- Lionel A. Tintignac
- Biozentrum, University of Basel, Basel, Switzerland; Department of Biomedicine, University of Basel, Basel, Switzerland; and INRA, UMR866 Dynamique Musculaire et Métabolisme, Montpellier, France
| | - Hans-Rudolf Brenner
- Biozentrum, University of Basel, Basel, Switzerland; Department of Biomedicine, University of Basel, Basel, Switzerland; and INRA, UMR866 Dynamique Musculaire et Métabolisme, Montpellier, France
| | - Markus A. Rüegg
- Biozentrum, University of Basel, Basel, Switzerland; Department of Biomedicine, University of Basel, Basel, Switzerland; and INRA, UMR866 Dynamique Musculaire et Métabolisme, Montpellier, France
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45
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Braun TP, Marks DL. The regulation of muscle mass by endogenous glucocorticoids. Front Physiol 2015; 6:12. [PMID: 25691871 PMCID: PMC4315033 DOI: 10.3389/fphys.2015.00012] [Citation(s) in RCA: 155] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 01/08/2015] [Indexed: 01/16/2023] Open
Abstract
Glucocorticoids are highly conserved fundamental regulators of energy homeostasis. In response to stress in the form of perceived danger or acute inflammation, glucocorticoids are released from the adrenal gland, rapidly mobilizing energy from carbohydrate, fat and protein stores. In the case of inflammation, mobilized protein is critical for the rapid synthesis of acute phase reactants and an efficient immune response to infection. While adaptive in response to infection, chronic mobilization can lead to a profound depletion of energy stores. Skeletal muscle represents the major body store of protein, and can become substantially atrophied under conditions of chronic inflammation. Glucocorticoids elicit the atrophy of muscle by increasing the rate of protein degradation by the ubiquitin-proteasome system and autophagy lysosome system. Protein synthesis is also suppressed at the level of translational initiation, preventing the production of new myofibrillar protein. Glucocorticoids also antagonize the action of anabolic regulators such as insulin further exacerbating the loss of protein and muscle mass. The loss of muscle mass in the context of chronic disease is a key feature of cachexia and contributes substantially to morbidity and mortality. A growing body of evidence demonstrates that glucocorticoid signaling is a common mediator of wasting, irrespective of the underlying initiator or disease state. This review will highlight fundamental mechanisms of glucocorticoid signaling and detail the mechanisms of glucocorticoid-induced muscle atrophy. Additionally, the evidence for glucocorticoids as a driver of muscle wasting in numerous disease states will be discussed. Given the burden of wasting diseases and the nodal nature of glucocorticoid signaling, effective anti-glucocorticoid therapy would be a valuable clinical tool. Therefore, the progress and potential pitfalls in the development of glucocorticoid antagonists for muscle wasting will be discussed.
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Affiliation(s)
- Theodore P Braun
- Department of Internal Medicine, University of Washington Medical Center Seattle, WA, USA ; Papé Family Pediatric Research Institute, Oregon Health and Science University Portland, OR, USA
| | - Daniel L Marks
- Department of Internal Medicine, University of Washington Medical Center Seattle, WA, USA
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46
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Sepulveda PV, Bush ED, Baar K. Pharmacology of manipulating lean body mass. Clin Exp Pharmacol Physiol 2015; 42:1-13. [PMID: 25311629 PMCID: PMC4383600 DOI: 10.1111/1440-1681.12320] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 09/29/2014] [Accepted: 09/29/2014] [Indexed: 01/04/2023]
Abstract
Dysfunction and wasting of skeletal muscle as a consequence of illness decreases the length and quality of life. Currently, there are few, if any, effective treatments available to address these conditions. Hence, the existence of this unmet medical need has fuelled large scientific efforts. Fortunately, these efforts have shown many of the underlying mechanisms adversely affecting skeletal muscle health. With increased understanding have come breakthrough disease-specific and broad spectrum interventions, some progressing through clinical development. The present review focuses its attention on the role of the antagonistic process regulating skeletal muscle mass before branching into prospective promising therapeutic targets and interventions. Special attention is given to therapies in development against cancer cachexia and Duchenne muscular dystrophy before closing remarks on design and conceptualization of future therapies are presented to the reader.
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Affiliation(s)
- Patricio V Sepulveda
- Department of Physiology, Monash University, Monash College Wellington Rd, Melbourne Victoria, Australia
| | - Ernest D Bush
- Akashi Therapeutics, Cambridge, MA, University of California Davis, Davis, CA, USA
| | - Keith Baar
- Departments of Neurobiology, Physiology and Behaviour and Physiology and Membrane Biology, University of California Davis, Davis, CA, USA
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47
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Abstract
Muscle RING finger 1 (MuRF1) and muscle atrophy F-box (MAFbx)/atrogin-1 were identified more than 10 years ago as two muscle-specific E3 ubiquitin ligases that are increased transcriptionally in skeletal muscle under atrophy-inducing conditions, making them excellent markers of muscle atrophy. In the past 10 years much has been published about MuRF1 and MAFbx with respect to their mRNA expression patterns under atrophy-inducing conditions, their transcriptional regulation, and their putative substrates. However, much remains to be learned about the physiological role of both genes in the regulation of mass and other cellular functions in striated muscle. Although both MuRF1 and MAFbx are enriched in skeletal, cardiac, and smooth muscle, this review will focus on the current understanding of MuRF1 and MAFbx in skeletal muscle, highlighting the critical questions that remain to be answered.
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Affiliation(s)
- Sue C Bodine
- Departments of Neurobiology, Physiology, and Behavior and Physiology and Membrane Biology, University of California Davis, Davis, California; and Northern California Veterans Affairs Health Systems, Mather, California
| | - Leslie M Baehr
- Membrane Biology, University of California Davis, Davis, California; and
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48
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Gonzalez-Freire M, de Cabo R, Studenski SA, Ferrucci L. The Neuromuscular Junction: Aging at the Crossroad between Nerves and Muscle. Front Aging Neurosci 2014; 6:208. [PMID: 25157231 PMCID: PMC4127816 DOI: 10.3389/fnagi.2014.00208] [Citation(s) in RCA: 203] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 07/25/2014] [Indexed: 01/19/2023] Open
Abstract
Aging is associated with a progressive loss of muscle mass and strength and a decline in neurophysiological functions. Age-related neuromuscular junction (NMJ) plays a key role in musculoskeletal impairment that occurs with aging. However, whether changes in the NMJ precede or follow the decline of muscle mass and strength remains unresolved. Many factors such as mitochondrial dysfunction, oxidative stress, inflammation, changes in the innervation of muscle fibers, and mechanical properties of the motor units probably perform an important role in NMJ degeneration and muscle mass and strength decline in late life. This review addresses the primary events that might lead to NMJ dysfunction with aging, including studies on biomarkers, signaling pathways, and animal models. Interventions such as caloric restriction and exercise may positively affect the NMJ through this mechanism and attenuate the age-related progressive impairment in motor function.
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Affiliation(s)
- Marta Gonzalez-Freire
- Translational Gerontology Branch, National Institute on Aging, Intramural Research Program, National Institutes of Health , Baltimore, MD , USA ; Longitudinal Studies Section, Baltimore Longitudinal Study of Aging, National Institute on Aging, National Institutes of Health , Baltimore, MD , USA
| | - Rafael de Cabo
- Translational Gerontology Branch, National Institute on Aging, Intramural Research Program, National Institutes of Health , Baltimore, MD , USA
| | - Stephanie A Studenski
- Translational Gerontology Branch, National Institute on Aging, Intramural Research Program, National Institutes of Health , Baltimore, MD , USA ; Longitudinal Studies Section, Baltimore Longitudinal Study of Aging, National Institute on Aging, National Institutes of Health , Baltimore, MD , USA
| | - Luigi Ferrucci
- Translational Gerontology Branch, National Institute on Aging, Intramural Research Program, National Institutes of Health , Baltimore, MD , USA ; Longitudinal Studies Section, Baltimore Longitudinal Study of Aging, National Institute on Aging, National Institutes of Health , Baltimore, MD , USA
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49
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Rudolf R, Khan MM, Labeit S, Deschenes MR. Degeneration of neuromuscular junction in age and dystrophy. Front Aging Neurosci 2014; 6:99. [PMID: 24904412 PMCID: PMC4033055 DOI: 10.3389/fnagi.2014.00099] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 05/08/2014] [Indexed: 12/27/2022] Open
Abstract
Functional denervation is a hallmark of aging sarcopenia as well as of muscular dystrophy. It is thought to be a major factor reducing skeletal muscle mass, particularly in the case of sarcopenia. Neuromuscular junctions (NMJs) serve as the interface between the nervous and skeletal muscular systems, and thus they may receive pathophysiological input of both pre- and post-synaptic origin. Consequently, NMJs are good indicators of motor health on a systemic level. Indeed, upon sarcopenia and dystrophy, NMJs morphologically deteriorate and exhibit altered characteristics of primary signaling molecules, such as nicotinic acetylcholine receptor and agrin. Since a remarkable reversibility of these changes can be observed by exercise, there is significant interest in understanding the molecular mechanisms underlying synaptic deterioration upon aging and dystrophy and how synapses are reset by the aforementioned treatments. Here, we review the literature that describes the phenomena observed at the NMJ in sarcopenic and dystrophic muscle as well as to how these alterations can be reversed and to what extent. In a second part, the current information about molecular machineries underlying these processes is reported.
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Affiliation(s)
- Rüdiger Rudolf
- Institute of Molecular and Cell Biology, University of Applied Sciences Mannheim , Mannheim , Germany ; Institute of Medical Technology, University of Heidelberg and University of Applied Sciences Mannheim , Mannheim , Germany ; Institute of Toxicology and Genetics, Karlsruhe Institute of Technology , Eggenstein-Leopoldshafen , Germany
| | - Muzamil Majid Khan
- Institute of Molecular and Cell Biology, University of Applied Sciences Mannheim , Mannheim , Germany ; Institute of Toxicology and Genetics, Karlsruhe Institute of Technology , Eggenstein-Leopoldshafen , Germany
| | - Siegfried Labeit
- Institute of Integrative Pathophysiology, University Medical Centre Mannheim , Mannheim , Germany
| | - Michael R Deschenes
- Department of Kinesiology and Health Sciences, The College of William and Mary , Williamsburg, VA , USA
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