51
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Gross SM, Lehman SL. Functional phosphorylation sites in cardiac myofilament proteins are evolutionarily conserved in skeletal myofilament proteins. Physiol Genomics 2016; 48:377-87. [PMID: 26993364 DOI: 10.1152/physiolgenomics.00112.2015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 03/11/2016] [Indexed: 01/14/2023] Open
Abstract
Protein phosphorylation plays an important role in regulating cardiac contractile function, but phosphorylation is not thought to play a regulatory role in skeletal muscle. To examine how myofilament phosphorylation arose in the human heart, we analyzed the amino acid sequences of 25 cardiac phosphorylation sites in animals ranging from fruit flies to humans. These analyses indicated that of the 25 human phosphorylation sites examined, 11 have been conserved across vertebrates and four have been sporadically present in vertebrates. Furthermore, all 11 of the cardiac sites found across vertebrates were present in skeletal muscle isoforms, along with three sites that were sporadically present. Based on the conservation of amino acid sequences between cardiac and skeletal contractile proteins, we tested for phosphorylation in mammalian skeletal muscle using several biochemical techniques and found evidence that multiple myofilament proteins were phosphorylated. Several of these phosphorylation sites were validated using mass spectrometry, including one site that is present in slow- and fast-twitch troponin I (TnI), but was lost in cardiac TnI. Thus, several myofilament phosphorylation sites present in the human heart likely arose in invertebrate muscle, have been evolutionarily conserved in skeletal muscle, and potentially have functional effects in both skeletal and cardiac muscle.
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Affiliation(s)
- Sean M Gross
- Department of Integrative Biology, University of California, Berkeley, Berkeley, California; and Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, Oregon
| | - Steven L Lehman
- Department of Integrative Biology, University of California, Berkeley, Berkeley, California; and
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52
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Terrill JR, Pinniger GJ, Graves JA, Grounds MD, Arthur PG. Increasing taurine intake and taurine synthesis improves skeletal muscle function in the mdx mouse model for Duchenne muscular dystrophy. J Physiol 2016; 594:3095-110. [PMID: 26659826 DOI: 10.1113/jp271418] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 11/18/2015] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Duchenne muscular dystrophy (DMD) is a fatal muscle wasting disease associated with increased inflammation, oxidative stress and myofibre necrosis. Cysteine precursor antioxidants such as N-acetyl cysteine (NAC) and l-2-oxothiazolidine-4-carboxylate (OTC) reduce dystropathology in the mdx mouse model for DMD, and we propose this is via increased synthesis of the amino acid taurine. We compared the capacity of OTC and taurine treatment to increase taurine content of mdx muscle, as well as effects on in vivo and ex vivo muscle function, inflammation and oxidative stress. Both treatments increased taurine in muscles, and improved many aspects of muscle function and reduced inflammation. Taurine treatment also reduced protein thiol oxidation and was overall more effective, as OTC treatment reduced body and muscle weight, suggesting some adverse effects of this drug. These data suggest that increasing dietary taurine is a better candidate for a therapeutic intervention for DMD. ABSTRACT Duchenne muscular dystrophy (DMD) is a fatal muscle wasting disease for which there is no widely available cure. Whilst the mechanism of loss of muscle function in DMD and the mdx mouse model are not fully understood, disruptions in intracellular calcium homeostasis, inflammation and oxidative stress are implicated. We have shown that protein thiol oxidation is increased in mdx muscle, and that the indirect thiol antioxidant l-2-oxothiazolidine-4-carboxylate (OTC), which increases cysteine availability, decreases pathology and increases in vivo strength. We propose that the protective effects of OTC are a consequence of conversion of cysteine to taurine, which has itself been shown to be beneficial to mdx pathology. This study compares the efficacy of taurine with OTC in decreasing dystropathology in mdx mice by measuring in vivo and ex vivo contractile function and measurements of inflammation and protein thiol oxidation. Increasing the taurine content of mdx muscle improved both in vivo and ex vivo muscle strength and function, potentially via anti-inflammatory and antioxidant effects of taurine. OTC treatment increased taurine synthesis in the liver and taurine content of mdx muscle, improved muscle function and decreased inflammation. However, OTC was less effective than taurine treatment, with OTC also decreasing body and EDL muscle weights, suggesting that OTC had some detrimental effects. These data support continued research into the use of taurine as a therapeutic intervention for DMD, and suggest that increasing dietary taurine is the better strategy for increasing taurine content and decreasing severity of dystropathology.
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Affiliation(s)
- Jessica R Terrill
- School of Chemistry and Biochemistry, the University of Western Australia, Perth, Western Australia.,School of Anatomy, Physiology and Human Biology, the University of Western Australia, Perth, Western Australia
| | - Gavin J Pinniger
- School of Anatomy, Physiology and Human Biology, the University of Western Australia, Perth, Western Australia
| | - Jamie A Graves
- School of Anatomy, Physiology and Human Biology, the University of Western Australia, Perth, Western Australia
| | - Miranda D Grounds
- School of Anatomy, Physiology and Human Biology, the University of Western Australia, Perth, Western Australia
| | - Peter G Arthur
- School of Chemistry and Biochemistry, the University of Western Australia, Perth, Western Australia
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53
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Lamboley CR, Wyckelsma VL, McKenna MJ, Murphy RM, Lamb GD. Ca(2+) leakage out of the sarcoplasmic reticulum is increased in type I skeletal muscle fibres in aged humans. J Physiol 2015; 594:469-81. [PMID: 26574292 DOI: 10.1113/jp271382] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 11/11/2015] [Indexed: 12/16/2022] Open
Abstract
KEY POINTS The amount of Ca(2+) stored in the sarcoplasmic reticulum (SR) of muscle fibres is decreased in aged individuals, and an important question is whether this results from increased Ca(2+) leakage out through the Ca(2+) release channels (ryanodine receptors; RyRs). The present study examined the effects of blocking the RyRs with Mg(2+), or applying a strong reducing treatment, on net Ca(2+) accumulation by the SR in skinned muscle fibres from Old (∼70 years) and Young (∼24 years) adults. Raising cytoplasmic [Mg(2+)] and reducing treatment increased net SR Ca(2+) accumulation in type I fibres of Old subjects relative to that in Young. The densities of RyRs and dihydropyridine receptors were not significantly changed in the muscle of Old subjects. These findings indicate that oxidative modification of the RyRs causes increased Ca(2+) leakage from the SR in muscle fibres in Old subjects, which probably deleteriously affects normal muscle function both directly and indirectly. ABSTRACT The present study examined whether the lower Ca(2+) storage levels in the sarcoplasmic reticulum (SR) in vastus lateralis muscle fibres in Old (70 ± 4 years) relative to Young (24 ± 4 years) human subjects is the result of increased leakage of Ca(2+) out of the SR through the Ca(2+) release channels/ryanodine receptors (RyRs) and due to oxidative modification of the RyRs. SR Ca(2+) accumulation in mechanically skinned muscle fibres was examined in the presence of 1, 3 or 10 mm cytoplasmic Mg(2+) because raising [Mg(2+)] strongly inhibits Ca(2+) efflux through the RyRs. In type I fibres of Old subjects, SR Ca(2+) accumulation in the presence of 1 mm Mg(2+) approached saturation at shorter loading times than in Young subjects, consistent with Ca(2+) leakage limiting net uptake, and raising [Mg(2+)] to 10 mm in such fibres increased maximal SR Ca(2+) accumulation. No significant differences were seen in type II fibres. Treatment with dithiothreitol (10 mm for 5 min), a strong reducing agent, also increased maximal SR Ca(2+) accumulation at 1 mm Mg(2+) in type I fibres of Old subjects but not in other fibres. The densities of dihydropyridine receptors and RyRs were not significantly different in muscles of Old relative to Young subjects. These findings indicate that Ca(2+) leakage from the SR is increased in type I fibres in Old subjects by reversible oxidative modification of the RyRs; this increased SR Ca(2+) leak is expected to have both direct and indirect deleterious effects on Ca(2+) movements and muscle function.
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Affiliation(s)
- C R Lamboley
- Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, Melbourne, VIC, Australia.,School of Life Sciences, La Trobe University, Melbourne, VIC 3086, Australia
| | - V L Wyckelsma
- Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, Melbourne, VIC, Australia.,Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
| | - M J McKenna
- Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, Melbourne, VIC, Australia
| | - R M Murphy
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
| | - G D Lamb
- School of Life Sciences, La Trobe University, Melbourne, VIC 3086, Australia
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54
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Sheng JJ, Jin JP. TNNI1, TNNI2 and TNNI3: Evolution, regulation, and protein structure-function relationships. Gene 2015; 576:385-94. [PMID: 26526134 DOI: 10.1016/j.gene.2015.10.052] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 09/21/2015] [Accepted: 10/20/2015] [Indexed: 12/11/2022]
Abstract
Troponin I (TnI) is the inhibitory subunit of the troponin complex in the sarcomeric thin filament of striated muscle and plays a central role in the calcium regulation of contraction and relaxation. Vertebrate TnI has evolved into three isoforms encoded by three homologous genes: TNNI1 for slow skeletal muscle TnI, TNNI2 for fast skeletal muscle TnI and TNNI3 for cardiac TnI, which are expressed under muscle type-specific and developmental regulations. To summarize the current knowledge on the TnI isoform genes and products, this review focuses on the evolution, gene regulation, posttranslational modifications, and structure-function relationship of TnI isoform proteins. Their physiological and medical significances are also discussed.
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Affiliation(s)
- Juan-Juan Sheng
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Jian-Ping Jin
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI 48201, USA.
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55
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Debold EP. Potential molecular mechanisms underlying muscle fatigue mediated by reactive oxygen and nitrogen species. Front Physiol 2015; 6:239. [PMID: 26388779 PMCID: PMC4555024 DOI: 10.3389/fphys.2015.00239] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 08/07/2015] [Indexed: 11/23/2022] Open
Abstract
Intense contractile activity causes a dramatic decline in the force and velocity generating capacity of skeletal muscle within a few minutes, a phenomenon that characterizes fatigue. Much of the research effort has focused on how elevated levels of the metabolites of ATP hydrolysis might inhibit the function of the contractile proteins. However, there is now growing evidence that elevated levels of reactive oxygen and nitrogen species (ROS/RNS), which also accumulate in the myoplasm during fatigue, also play a causative role in this type of fatigue. The most compelling evidence comes from observations demonstrating that pre-treatment of intact muscle with a ROS scavenger can significantly attenuate the development of fatigue. A clear advantage of this line of inquiry is that the molecular targets and protein modifications of some of the ROS scavengers are well-characterized enabling researchers to begin to identify potential regions and even specific amino acid residues modified during fatigue. Combining this knowledge with assessments of contractile properties from the whole muscle level down to the dynamic motions within specific contractile proteins enable the linking of the structural modifications to the functional impacts, using advanced chemical and biophysical techniques. Based on this approach at least two areas are beginning emerge as potentially important sites, the regulatory protein troponin and the actin binding region of myosin. This review highlights some of these recent efforts which have the potential to offer uniquely precise information on the underlying molecular basis of fatigue. This work may also have implications beyond muscle fatigue as ROS/RNS mediated protein modifications are also thought to play a role in the loss of muscle function with aging and in some acute pathologies like cardiac arrest and ischemia.
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Affiliation(s)
- Edward P Debold
- Department of Kinesiology, University of Massachusetts Amherst, MA, USA
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56
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Juel C, Hostrup M, Bangsbo J. The effect of exercise and beta2-adrenergic stimulation on glutathionylation and function of the Na,K-ATPase in human skeletal muscle. Physiol Rep 2015; 3:3/8/e12515. [PMID: 26296772 PMCID: PMC4562595 DOI: 10.14814/phy2.12515] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Potassium and sodium displacements across the skeletal muscle membrane during exercise may cause fatigue and are in part controlled by the Na,K-ATPase. Regulation of the Na,K-ATPase is therefore important for muscle functioning. We investigated the effect of oxidative stress (glutathionylation) on Na,K-ATPase activity. Ten male subjects performed three bouts of 4-min submaximal exercise followed by intense exercise to exhaustion with and without beta2-adrenergic stimulation with terbutaline. Muscle biopsies were obtained from m. vastus lateralis at rest (Control samples) and at exhaustion. In vitro glutathionylation reduced (P < 0.05) maximal Na,K-ATPase activity in a dose-dependent manner. Na,K-ATPase α subunits, purified by immunoprecipitation and tested by glutathione (GSH) antibodies, had a basal glutathionylation in Control samples and no further glutathionylation with exercise and beta2-adrenergic stimulation. Immunoprecipitation with an anti-GSH antibody and subsequent immunodetection with β1 antibodies showed approximately 20% glutathionylation in Control samples and further glutathionylation after exercise (to 32%) and beta2-adrenergic stimulation (to 38%, P < 0.05). Combining exercise and beta2-adrenergic stimulation raised the β1 glutathionylation to 45% (P < 0.05). In conclusion, both α and β1 subunits of the Na,K-ATPase were glutathionylated in Control samples, which indicates that the maximal Na,K-ATPase activity is overestimated if based on protein density only. β1 subunits are further glutathionylated by exercise and beta2-adrenergic stimulation. Our data suggest that glutathionylation contributes to the complex regulation of Na,K-ATPase function in human skeletal muscle. Glutathionylation of the Na,K-ATPase may explain reductions in maximal Na,K-ATPase activity after exercise, which may be involved in muscle fatigue.
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Affiliation(s)
- Carsten Juel
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Morten Hostrup
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Jens Bangsbo
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
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57
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Cheng AJ, Chaillou T, Gineste C, Schlittler M. Intracellular Ca(2+) handling and myofibrillar Ca(2+) sensitivity are defective in single muscle fibres of aged humans. J Physiol 2015; 593:3237-8. [PMID: 26228551 DOI: 10.1113/jp270960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 06/11/2015] [Indexed: 11/08/2022] Open
Affiliation(s)
- Arthur J Cheng
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Thomas Chaillou
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Charlotte Gineste
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Maja Schlittler
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
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58
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Breitkreuz M, Hamdani N. A change of heart: oxidative stress in governing muscle function? Biophys Rev 2015; 7:321-341. [PMID: 28510229 DOI: 10.1007/s12551-015-0175-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 06/08/2015] [Indexed: 02/07/2023] Open
Abstract
Redox/cysteine modification of proteins that regulate calcium cycling can affect contraction in striated muscles. Understanding the nature of these modifications would present the possibility of enhancing cardiac function through reversible cysteine modification of proteins, with potential therapeutic value in heart failure with diastolic dysfunction. Both heart failure and muscular dystrophy are characterized by abnormal redox balance and nitrosative stress. Recent evidence supports the synergistic role of oxidative stress and inflammation in the progression of heart failure with preserved ejection fraction, in concert with endothelial dysfunction and impaired nitric oxide-cyclic guanosine monophosphate-protein kinase G signalling via modification of the giant protein titin. Although antioxidant therapeutics in heart failure with diastolic dysfunction have no marked beneficial effects on the outcome of patients, it, however, remains critical to the understanding of the complex interactions of oxidative/nitrosative stress with pro-inflammatory mechanisms, metabolic dysfunction, and the redox modification of proteins characteristic of heart failure. These may highlight novel approaches to therapeutic strategies for heart failure with diastolic dysfunction. In this review, we provide an overview of oxidative stress and its effects on pathophysiological pathways. We describe the molecular mechanisms driving oxidative modification of proteins and subsequent effects on contractile function, and, finally, we discuss potential therapeutic opportunities for heart failure with diastolic dysfunction.
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Affiliation(s)
- Martin Breitkreuz
- Department of Cardiovascular Physiology, Ruhr University Bochum, MA 3/56, 44780, Bochum, Germany
| | - Nazha Hamdani
- Department of Cardiovascular Physiology, Ruhr University Bochum, MA 3/56, 44780, Bochum, Germany.
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59
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Gejl KD, Hvid LG, Willis SJ, Andersson E, Holmberg HC, Jensen R, Frandsen U, Hansen J, Plomgaard P, Ørtenblad N. Repeated high-intensity exercise modulates Ca2+sensitivity of human skeletal muscle fibers. Scand J Med Sci Sports 2015; 26:488-97. [DOI: 10.1111/sms.12483] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/26/2015] [Indexed: 12/17/2022]
Affiliation(s)
- K. D. Gejl
- Department of Sports Science and Clinical Biomechanics; SDU Muscle Research Cluster; University of Southern Denmark; Odense Denmark
| | - L. G. Hvid
- Department of Sports Science and Clinical Biomechanics; SDU Muscle Research Cluster; University of Southern Denmark; Odense Denmark
| | - S. J. Willis
- Department of Health Sciences; Swedish Winter Sports Research Centre; Mid Sweden University; Östersund Sweden
| | - E. Andersson
- Department of Health Sciences; Swedish Winter Sports Research Centre; Mid Sweden University; Östersund Sweden
| | - H.-C. Holmberg
- Department of Health Sciences; Swedish Winter Sports Research Centre; Mid Sweden University; Östersund Sweden
- Swedish Olympic Committee; Stockholm Sweden
| | - R. Jensen
- Department of Sports Science and Clinical Biomechanics; SDU Muscle Research Cluster; University of Southern Denmark; Odense Denmark
| | - U. Frandsen
- Department of Sports Science and Clinical Biomechanics; SDU Muscle Research Cluster; University of Southern Denmark; Odense Denmark
| | - J. Hansen
- Department of Infectious Diseases and CMRC; The Centre of Inflammation and Metabolism; Rigshospitalet; Copenhagen Denmark
- Department of Clinical Biochemistry; Rigshospitalet; Copenhagen Denmark
| | - P. Plomgaard
- Department of Infectious Diseases and CMRC; The Centre of Inflammation and Metabolism; Rigshospitalet; Copenhagen Denmark
- Department of Clinical Biochemistry; Rigshospitalet; Copenhagen Denmark
| | - N. Ørtenblad
- Department of Sports Science and Clinical Biomechanics; SDU Muscle Research Cluster; University of Southern Denmark; Odense Denmark
- Department of Health Sciences; Swedish Winter Sports Research Centre; Mid Sweden University; Östersund Sweden
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60
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Lamboley CR, Wyckelsma VL, Dutka TL, McKenna MJ, Murphy RM, Lamb GD. Contractile properties and sarcoplasmic reticulum calcium content in type I and type II skeletal muscle fibres in active aged humans. J Physiol 2015; 593:2499-514. [PMID: 25809942 DOI: 10.1113/jp270179] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 03/23/2015] [Indexed: 01/25/2023] Open
Abstract
KEY POINTS Muscle weakness in old age is due in large part to an overall loss of skeletal muscle tissue, but it remains uncertain how much also stems from alterations in the properties of the individual muscle fibres. This study examined the contractile properties and amount of stored intracellular calcium in single muscle fibres of Old (70 ± 4 years) and Young (22 ± 3 years) adults. The maximum level of force production (per unit cross-sectional area) in fast twitch fibres in Old subjects was lower than in Young subjects, and the fibres were also less sensitive to activation by calcium. The amount of calcium stored inside muscle fibres and available to trigger contraction was also lower in both fast- and slow-twitch muscle fibres in the Old subjects. These findings indicate that muscle weakness in old age stems in part from an impaired capacity for force production in the individual muscle fibres. ABSTRACT This study examined the contractile properties and sarcoplasmic reticulum (SR) Ca(2+) content in mechanically skinned vastus lateralis muscle fibres of Old (70 ± 4 years) and Young (22 ± 3 years) humans to investigate whether changes in muscle fibre properties contribute to muscle weakness in old age. In type II fibres of Old subjects, specific force was reduced by ∼17% and Ca(2+) sensitivity was also reduced (pCa50 decreased ∼0.05 pCa units) relative to that in Young. S-Glutathionylation of fast troponin I (TnIf ) markedly increased Ca(2+) sensitivity in type II fibres, but the increase was significantly smaller in Old versus Young (+0.136 and +0.164 pCa unit increases, respectively). Endogenous and maximal SR Ca(2+) content were significantly smaller in both type I and type II fibres in Old subjects. In fibres of Young, the SR could be nearly fully depleted of Ca(2+) by a combined caffeine and low Mg(2+) stimulus, whereas in fibres of Old the amount of non-releasable Ca(2+) was significantly increased (by > 12% of endogenous Ca(2+) content). Western blotting showed an increased proportion of type I fibres in Old subjects, and increased amounts of calsequestrin-2 and calsequestrin-like protein. The findings suggest that muscle weakness in old age is probably attributable in part to (i) an increased proportion of type I fibres, (ii) a reduction in both maximum specific force and Ca(2+) sensitivity in type II fibres, and also a decreased ability of S-glutathionylation of TnIf to counter the fatiguing effects of metabolites on Ca(2+) sensitivity, and (iii) a reduction in the amount of releasable SR Ca(2+) in both fibre types.
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Affiliation(s)
- C R Lamboley
- Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, PO Box 14428, Melbourne, Victoria, 8001, Australia
| | - V L Wyckelsma
- Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, PO Box 14428, Melbourne, Victoria, 8001, Australia.,La Trobe Rural Health School, La Trobe University, Melbourne, Victoria, 3086, Australia
| | - T L Dutka
- School of Life Sciences, La Trobe University, Melbourne, Victoria, 3086, Australia
| | - M J McKenna
- Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, PO Box 14428, Melbourne, Victoria, 8001, Australia
| | - R M Murphy
- School of Molecular Sciences, La Trobe University, Melbourne, Victoria, 3086, Australia
| | - G D Lamb
- School of Life Sciences, La Trobe University, Melbourne, Victoria, 3086, Australia
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61
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Impact of oxidative stress on exercising skeletal muscle. Biomolecules 2015; 5:356-77. [PMID: 25866921 PMCID: PMC4496677 DOI: 10.3390/biom5020356] [Citation(s) in RCA: 229] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 03/24/2015] [Accepted: 03/30/2015] [Indexed: 01/01/2023] Open
Abstract
It is well established that muscle contractions during exercise lead to elevated levels of reactive oxygen species (ROS) in skeletal muscle. These highly reactive molecules have many deleterious effects, such as a reduction of force generation and increased muscle atrophy. Since the discovery of exercise-induced oxidative stress several decades ago, evidence has accumulated that ROS produced during exercise also have positive effects by influencing cellular processes that lead to increased expression of antioxidants. These molecules are particularly elevated in regularly exercising muscle to prevent the negative effects of ROS by neutralizing the free radicals. In addition, ROS also seem to be involved in the exercise-induced adaptation of the muscle phenotype. This review provides an overview of the evidences to date on the effects of ROS in exercising muscle. These aspects include the sources of ROS, their positive and negative cellular effects, the role of antioxidants, and the present evidence on ROS-dependent adaptations of muscle cells in response to physical exercise.
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62
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Zhang J, Grek C, Ye ZW, Manevich Y, Tew KD, Townsend DM. Pleiotropic functions of glutathione S-transferase P. Adv Cancer Res 2015; 122:143-75. [PMID: 24974181 DOI: 10.1016/b978-0-12-420117-0.00004-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Glutathione S-transferase P (GSTP) is one member of the GST superfamily that is prevalently expressed in mammals. Known to possess catalytic activity through deprotonating glutathione allowing formation of thioether bonds with electrophilic substrates, more recent discoveries have broadened our understanding of the biological roles of this protein. In addition to catalytic detoxification, other properties so far ascribed to GSTP include chaperone functions, regulation of nitric oxide pathways, regulation of a variety of kinase signaling pathways, and participation in the forward reaction of protein S-glutathionylation. The expression of GSTP has been linked with cancer and other human pathologies and more recently even with drug addiction. With respect to human health, polymorphic variants of GSTP may determine individual susceptibility to oxidative stress and/or be critical in the design and development of drugs that have used redox pathways as a discovery platform.
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Affiliation(s)
- Jie Zhang
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Christina Grek
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Zhi-Wei Ye
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Yefim Manevich
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Kenneth D Tew
- Professor and Chairman, Department of Cell and Molecular Pharmacology, John C. West Chair of Cancer Research, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Danyelle M Townsend
- Department of Pharmaceutical and Biomedical Sciences, Medical University of South Carolina, Charleston, South Carolina, USA.
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63
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Watanabe D, Kanzaki K, Kuratani M, Matsunaga S, Yanaka N, Wada M. Contribution of impaired myofibril and ryanodine receptor function to prolonged low-frequency force depression after in situ stimulation in rat skeletal muscle. J Muscle Res Cell Motil 2015; 36:275-86. [DOI: 10.1007/s10974-015-9409-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 02/12/2015] [Indexed: 01/21/2023]
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64
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Cheng AJ, Bruton JD, Lanner JT, Westerblad H. Antioxidant treatments do not improve force recovery after fatiguing stimulation of mouse skeletal muscle fibres. J Physiol 2014; 593:457-72. [PMID: 25630265 DOI: 10.1113/jphysiol.2014.279398] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 10/30/2014] [Indexed: 12/20/2022] Open
Abstract
The contractile performance of skeletal muscle declines during intense activities, i.e. fatigue develops. Fatigued muscle can enter a state of prolonged low-frequency force depression (PLFFD). PLFFD can be due to decreased tetanic free cytosolic [Ca(2+) ] ([Ca(2+) ]i ) and/or decreased myofibrillar Ca(2+) sensitivity. Increases in reactive oxygen and nitrogen species (ROS/RNS) may contribute to fatigue-induced force reductions. We studied whether pharmacological ROS/RNS inhibition delays fatigue and/or counteracts the development of PLFFD. Mechanically isolated mouse fast-twitch fibres were fatigued by sixty 150 ms, 70 Hz tetani given every 1 s. Experiments were performed in standard Tyrode solution (control) or in the presence of: NADPH oxidase (NOX) 2 inhibitor (gp91ds-tat); NOX4 inhibitor (GKT137831); mitochondria-targeted antioxidant (SS-31); nitric oxide synthase (NOS) inhibitor (l-NAME); the general antioxidant N-acetylcysteine (NAC); a cocktail of SS-31, l-NAME and NAC. Spatially and temporally averaged [Ca(2+) ]i and peak force were reduced by ∼20% and ∼70% at the end of fatiguing stimulation, respectively, with no marked differences between groups. PLFFD was similar in all groups, with 30 Hz force being decreased by ∼60% at 30 min of recovery. PLFFD was mostly due to decreased tetanic [Ca(2+) ]i in control fibres and in the presence of NOX2 or NOX4 inhibitors. Conversely, in fibres exposed to SS-31 or the anti ROS/RNS cocktail, tetanic [Ca(2+) ]i was not decreased during recovery so PLFFD was only caused by decreased myofibrillar Ca(2+) sensitivity. The cocktail also increased resting [Ca(2+) ]i and ultimately caused cell death. In conclusion, ROS/RNS-neutralizing compounds did not counteract the force decline during or after induction of fatigue.
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Affiliation(s)
- Arthur J Cheng
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
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65
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Smith IC, Vandenboom R, Tupling AR. Juxtaposition of the changes in intracellular calcium and force during staircase potentiation at 30 and 37°C. J Gen Physiol 2014; 144:561-70. [PMID: 25422504 PMCID: PMC4242813 DOI: 10.1085/jgp.201411257] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Temperature-dependent changes in basal calcium and in the calcium transient contribute to force potentiation during repetitive stimulation. Ca2+ entry during the action potential stimulates muscle contraction. During repetitive low frequency stimulation, skeletal muscle undergoes staircase potentiation (SP), a progressive increase in the peak twitch force induced by each successive stimulus. Multiple mechanisms, including myosin regulatory light chain phosphorylation, likely contribute to SP, a temperature-dependent process. Here, we used the Ca2+-sensitive fluorescence indicators acetoxymethyl (AM)-furaptra and AM-fura-2 to examine the intracellular Ca2+ transient (ICT) and the baseline Ca2+ level at the onset of each ICT during SP at 30 and 37°C in mouse lumbrical muscle. The stimulation protocol, 8 Hz for 8 s, resulted in a 27 ± 3% increase in twitch force at 37°C and a 7 ± 2% decrease in twitch force at 30°C (P < 0.05). Regardless of temperature, the peak rate of force production (+df/dt) was higher in all twitches relative to the first twitch (P < 0.05). Consistent with the differential effects of stimulation on twitch force at the two temperatures, raw ICT amplitude decreased during repetitive stimulation at 30°C (P < 0.05) but not at 37°C. Cytosolic Ca2+ accumulated during SP such that baseline Ca2+ at the onset of ICTs occurring late in the train was higher (P < 0.05) than that of those occurring early in the train. ICT duration increased progressively at both temperatures. This effect was not entirely proportional to the changes in twitch duration, as twitch duration characteristically decreased before increasing late in the protocol. This is the first study identifying a changing ICT as an important, and temperature-sensitive, modulator of muscle force during repetitive stimulation. Moreover, we extend previous observations by demonstrating that contraction-induced increases in baseline Ca2+ coincide with greater +df/dt but not necessarily with higher twitch force.
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Affiliation(s)
- Ian C Smith
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Rene Vandenboom
- Department of Kinesiology, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| | - A Russell Tupling
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
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66
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Beckendorf L, Linke WA. Emerging importance of oxidative stress in regulating striated muscle elasticity. J Muscle Res Cell Motil 2014; 36:25-36. [PMID: 25373878 PMCID: PMC4352196 DOI: 10.1007/s10974-014-9392-y] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 10/03/2014] [Indexed: 12/11/2022]
Abstract
The contractile function of striated muscle cells is altered by oxidative/nitrosative stress, which can be observed under physiological conditions but also in diseases like heart failure or muscular dystrophy. Oxidative stress causes oxidative modifications of myofilament proteins and can impair myocyte contractility. Recent evidence also suggests an important effect of oxidative stress on muscle elasticity and passive stiffness via modifications of the giant protein titin. In this review we provide a short overview of known oxidative modifications in thin and thick filament proteins and then discuss in more detail those oxidative stress-related modifications altering titin stiffness directly or indirectly. Direct modifications of titin include reversible disulfide bonding within the cardiac-specific N2-Bus domain, which increases titin stiffness, and reversible S-glutathionylation of cryptic cysteines in immunoglobulin-like domains, which only takes place after the domains have unfolded and which reduces titin stiffness in cardiac and skeletal muscle. Indirect effects of oxidative stress on titin can occur via reversible modifications of protein kinase signalling pathways (especially the NO-cGMP-PKG axis), which alter the phosphorylation level of certain disordered titin domains and thereby modulate titin stiffness. Oxidative stress also activates proteases such as matrix-metalloproteinase-2 and (indirectly via increasing the intracellular calcium level) calpain-1, both of which cleave titin to irreversibly reduce titin-based stiffness. Although some of these mechanisms require confirmation in the in vivo setting, there is evidence that oxidative stress-related modifications of titin are relevant in the context of biomarker design and represent potential targets for therapeutic intervention in some forms of muscle and heart disease.
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Affiliation(s)
- Lisa Beckendorf
- Department of Cardiovascular Physiology, Institute of Physiology, Ruhr University Bochum, MA 3/56, 44780, Bochum, Germany
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67
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Moen RJ, Cornea S, Oseid DE, Binder BP, Klein JC, Thomas DD. Redox-sensitive residue in the actin-binding interface of myosin. Biochem Biophys Res Commun 2014; 453:345-9. [PMID: 25264102 PMCID: PMC4272649 DOI: 10.1016/j.bbrc.2014.09.072] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 09/18/2014] [Indexed: 12/22/2022]
Abstract
We have examined the chemical and functional reversibility of oxidative modification in myosin. Redox regulation has emerged as a crucial modulator of protein function, with particular relevance to aging. We previously identified a single methionine residue in Dictyostelium discoideum (Dicty) myosin II (M394, near the myosin cardiomyopathy loop in the actin-binding interface) that is functionally sensitive to oxidation. We now show that oxidation of M394 is reversible by methionine sulfoxide reductase (Msr), restoring actin-activated ATPase activity. Sequence alignment reveals that M394 of Dicty myosin II is a cysteine residue in all human isoforms of skeletal and cardiac myosin. Using Dicty myosin II as a model for site-specific redox sensitivity of this Cys residue, the M394C mutant can be glutathionylated in vitro, resulting in reversible inhibition of actin-activated ATPase activity, with effects similar to those of methionine oxidation at this site. This work illustrates the potential for myosin to function as a redox sensor in both non-muscle and muscle cells, modulating motility/contractility in response to oxidative stress.
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Affiliation(s)
- Rebecca J Moen
- Department of Chemistry and Geology, Minnesota State University, Mankato, MN 56001, United States
| | - Sinziana Cornea
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States
| | - Daniel E Oseid
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States
| | - Benjamin P Binder
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States
| | - Jennifer C Klein
- Department of Biology, University of Wisconsin, Lacrosse, Lacrosse, MN 54601, United States
| | - David D Thomas
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States.
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68
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Guellich A, Negroni E, Decostre V, Demoule A, Coirault C. Altered cross-bridge properties in skeletal muscle dystrophies. Front Physiol 2014; 5:393. [PMID: 25352808 PMCID: PMC4196474 DOI: 10.3389/fphys.2014.00393] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 09/23/2014] [Indexed: 12/20/2022] Open
Abstract
Force and motion generated by skeletal muscle ultimately depends on the cyclical interaction of actin with myosin. This mechanical process is regulated by intracellular Ca2+ through the thin filament-associated regulatory proteins i.e.; troponins and tropomyosin. Muscular dystrophies are a group of heterogeneous genetic affections characterized by progressive degeneration and weakness of the skeletal muscle as a consequence of loss of muscle tissue which directly reduces the number of potential myosin cross-bridges involved in force production. Mutations in genes responsible for skeletal muscle dystrophies (MDs) have been shown to modify the function of contractile proteins and cross-bridge interactions. Altered gene expression or RNA splicing or post-translational modifications of contractile proteins such as those related to oxidative stress, may affect cross-bridge function by modifying key proteins of the excitation-contraction coupling. Micro-architectural change in myofilament is another mechanism of altered cross-bridge performance. In this review, we provide an overview about changes in cross-bridge performance in skeletal MDs and discuss their ultimate impacts on striated muscle function.
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Affiliation(s)
- Aziz Guellich
- Service de Cardiologie, Hôpital Henri Mondor, University Paris-Est Créteil Créteil, France ; Equipe 8, Institut National de la Santé et de la Recherche Médicale Créteil, France
| | - Elisa Negroni
- UMRS 974, Institut National de la Santé et de la Recherche Médicale Paris, France ; UM 76, Université Pierre et Marie Curie, Sorbonne Universités Paris, France ; UMR 7215, Centre National de la Recherche Scientifique Paris, France ; Institut de Myologie Paris, France
| | | | - Alexandre Demoule
- UMRS 974, Institut National de la Santé et de la Recherche Médicale Paris, France ; UM 76, Université Pierre et Marie Curie, Sorbonne Universités Paris, France ; UMR 7215, Centre National de la Recherche Scientifique Paris, France ; Institut de Myologie Paris, France ; Assistance Publique-Hopitaux de Paris, Service de Pneumologie et Reanimation Medicale Paris, France
| | - Catherine Coirault
- UMRS 974, Institut National de la Santé et de la Recherche Médicale Paris, France ; UM 76, Université Pierre et Marie Curie, Sorbonne Universités Paris, France ; UMR 7215, Centre National de la Recherche Scientifique Paris, France ; Institut de Myologie Paris, France
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69
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Juel C. Oxidative stress (glutathionylation) and Na,K-ATPase activity in rat skeletal muscle. PLoS One 2014; 9:e110514. [PMID: 25310715 PMCID: PMC4195747 DOI: 10.1371/journal.pone.0110514] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 09/18/2014] [Indexed: 11/20/2022] Open
Abstract
Background Changes in ion distribution across skeletal muscle membranes during muscle activity affect excitability and may impair force development. These changes are counteracted by the Na,K-ATPase. Regulation of the Na,K-ATPase is therefore important for skeletal muscle function. The present study investigated the presence of oxidative stress (glutathionylation) on the Na,K-ATPase in rat skeletal muscle membranes. Results Immunoprecipitation with an anti-glutathione antibody and subsequent immunodetection of Na,K-ATPase protein subunits demonstrated 9.0±1.3% and 4.1±1.0% glutathionylation of the α isoforms in oxidative and glycolytic skeletal muscle, respectively. In oxidative muscle, 20.0±6.1% of the β1 units were glutathionylated, whereas 14.8±2.8% of the β2-subunits appear to be glutathionylated in glycolytic muscle. Treatment with the reducing agent dithiothreitol (DTT, 1 mM) increased the in vitro maximal Na,K-ATPase activity by 19% (P<0.05) in membranes from glycolytic muscle. Oxidized glutathione (GSSG, 0–10 mM) increased the in vitro glutathionylation level detected with antibodies, and decreased the in vitro maximal Na,K-ATPase activity in a dose-dependent manner, and with a larger effect in oxidative compared to glycolytic skeletal muscle. Conclusion This study demonstrates the existence of basal glutathionylation of both the α and the β units of rat skeletal muscle Na,K-ATPase. In addition, the study suggests a negative correlation between glutathionylation levels and maximal Na,K-ATPase activity. Perspective Glutathionylation likely contributes to the complex regulation of Na,K-ATPase function in skeletal muscle. Especially, glutathionylation induced by oxidative stress may have a role in Na,K-ATPase regulation during prolonged muscle activity.
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Affiliation(s)
- Carsten Juel
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
- * E-mail:
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70
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Abstract
The interaction between antioxidant glutathione and the free thiol in susceptible cysteine residues of proteins leads to reversible protein S-glutathionylation. This reaction ensures cellular homeostasis control (as a common redox-dependent post-translational modification associated with signal transduction) and intervenes in oxidative stress-related cardiovascular pathology (as initiated by redox imbalance). The purpose of this review is to evaluate the recent knowledge on protein S-glutathionylation in terms of chemistry, broad cellular intervention, specific quantification, and potential for therapeutic exploitation. The data bases searched were Medline and PubMed, from 2009 to 2014 (term: glutathionylation). Protein S-glutathionylation ensures protection of protein thiols against irreversible over-oxidation, operates as a biological redox switch in both cell survival (influencing kinases and protein phosphatases pathways) and cell death (by potentiation of apoptosis), and cross-talks with phosphorylation and with S-nitrosylation. Collectively, protein S-glutathionylation appears as a valuable biomarker for oxidative stress, with potential for translation into novel therapeutic strategies.
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Affiliation(s)
- Doina Popov
- Institute of Cellular Biology and Pathology "N. Simionescu" of the Romanian Academy , 8, B.P. Hasdeu Street, Bucharest 050568 , Romania
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71
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Callahan DM, Miller MS, Sweeny AP, Tourville TW, Slauterbeck JR, Savage PD, Maugan DW, Ades PA, Beynnon BD, Toth MJ. Muscle disuse alters skeletal muscle contractile function at the molecular and cellular levels in older adult humans in a sex-specific manner. J Physiol 2014; 592:4555-73. [PMID: 25038243 DOI: 10.1113/jphysiol.2014.279034] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Physical inactivity that accompanies ageing and disease may hasten disability by reducing skeletal muscle contractility. To characterize skeletal muscle functional adaptations to muscle disuse, we compared contractile performance at the molecular, cellular and whole‐muscle levels in healthy active older men and women (n = 15) and inactive older men and women with advanced‐stage, symptomatic knee osteoarthritis (OA) (n = 16). OA patients showed reduced (P < 0.01) knee extensor function. At the cellular level, single muscle fibre force production was reduced in OA patients in myosin heavy chain (MHC) I and IIA fibres (both P < 0.05) and differences in IIA fibres persisted after adjustments for fibre cross‐sectional area (P < 0.05). Although no group differences in contractile velocity or power output were found for any fibre type, sex was found to modify the effect of OA, with a reduction in MHC IIA power output and a trend towards reduced shortening velocity in women, but increases in both variables in men (P < 0.05 and P = 0.07, respectively). At the molecular level, these adaptations in MHC IIA fibre function were explained by sex‐specific differences (P ≤ 0.05) in myosin–actin cross‐bridge kinetics. Additionally, cross‐bridge kinetics were slowed in MHC I fibres in OA patients (P < 0.01), attributable entirely to reductions in women with knee OA (P < 0.05), a phenotype that could be reproduced in vitro by chemical modification of protein thiol residues. Our results identify molecular and cellular functional adaptations in skeletal muscle that may contribute to reduced physical function with knee OA‐associated muscle disuse, with sex‐specific differences that may explain a greater disposition towards disability in women.
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Affiliation(s)
- Damien M Callahan
- Department of Medicine, College of Medicine, University of Vermont, Burlington, VT, USA
| | - Mark S Miller
- Department of Molecular Physiology and Biophysics, College of Medicine, University of Vermont, Burlington, VT, USA
| | - Andrew P Sweeny
- Department of Medicine, College of Medicine, University of Vermont, Burlington, VT, USA
| | - Timothy W Tourville
- Department of Orthopaedics and Rehabilitation, College of Medicine, University of Vermont, Burlington, VT, USA
| | - James R Slauterbeck
- Department of Orthopaedics and Rehabilitation, College of Medicine, University of Vermont, Burlington, VT, USA
| | - Patrick D Savage
- Department of Medicine, College of Medicine, University of Vermont, Burlington, VT, USA
| | - David W Maugan
- Department of Molecular Physiology and Biophysics, College of Medicine, University of Vermont, Burlington, VT, USA
| | - Philip A Ades
- Department of Medicine, College of Medicine, University of Vermont, Burlington, VT, USA
| | - Bruce D Beynnon
- Department of Orthopaedics and Rehabilitation, College of Medicine, University of Vermont, Burlington, VT, USA
| | - Michael J Toth
- Department of Medicine, College of Medicine, University of Vermont, Burlington, VT, USA Department of Molecular Physiology and Biophysics, College of Medicine, University of Vermont, Burlington, VT, USA
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72
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Alegre-Cebollada J, Kosuri P, Giganti D, Eckels E, Rivas-Pardo JA, Hamdani N, Warren CM, Solaro RJ, Linke WA, Fernández JM. S-glutathionylation of cryptic cysteines enhances titin elasticity by blocking protein folding. Cell 2014; 156:1235-1246. [PMID: 24630725 DOI: 10.1016/j.cell.2014.01.056] [Citation(s) in RCA: 147] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 10/17/2013] [Accepted: 01/24/2014] [Indexed: 12/16/2022]
Abstract
The giant elastic protein titin is a determinant factor in how much blood fills the left ventricle during diastole and thus in the etiology of heart disease. Titin has been identified as a target of S-glutathionylation, an end product of the nitric-oxide-signaling cascade that increases cardiac muscle elasticity. However, it is unknown how S-glutathionylation may regulate the elasticity of titin and cardiac tissue. Here, we show that mechanical unfolding of titin immunoglobulin (Ig) domains exposes buried cysteine residues, which then can be S-glutathionylated. S-glutathionylation of cryptic cysteines greatly decreases the mechanical stability of the parent Ig domain as well as its ability to fold. Both effects favor a more extensible state of titin. Furthermore, we demonstrate that S-glutathionylation of cryptic cysteines in titin mediates mechanochemical modulation of the elasticity of human cardiomyocytes. We propose that posttranslational modification of cryptic residues is a general mechanism to regulate tissue elasticity.
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Affiliation(s)
| | - Pallav Kosuri
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA; Graduate Program in Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - David Giganti
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Edward Eckels
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA; Columbia College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | | | - Nazha Hamdani
- Department of Cardiovascular Physiology, Ruhr University Bochum, 44780 Bochum, Germany
| | - Chad M Warren
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - R John Solaro
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Wolfgang A Linke
- Department of Cardiovascular Physiology, Ruhr University Bochum, 44780 Bochum, Germany
| | - Julio M Fernández
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA.
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73
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Alegre-Cebollada J, Kosuri P, Giganti D, Eckels E, Rivas-Pardo JA, Hamdani N, Warren CM, Solaro RJ, Linke WA, Fernández JM. S-glutathionylation of cryptic cysteines enhances titin elasticity by blocking protein folding. Cell 2014. [PMID: 24630725 DOI: 10.1016/j.cell.2014.01.056.s-glutathionylation] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
The giant elastic protein titin is a determinant factor in how much blood fills the left ventricle during diastole and thus in the etiology of heart disease. Titin has been identified as a target of S-glutathionylation, an end product of the nitric-oxide-signaling cascade that increases cardiac muscle elasticity. However, it is unknown how S-glutathionylation may regulate the elasticity of titin and cardiac tissue. Here, we show that mechanical unfolding of titin immunoglobulin (Ig) domains exposes buried cysteine residues, which then can be S-glutathionylated. S-glutathionylation of cryptic cysteines greatly decreases the mechanical stability of the parent Ig domain as well as its ability to fold. Both effects favor a more extensible state of titin. Furthermore, we demonstrate that S-glutathionylation of cryptic cysteines in titin mediates mechanochemical modulation of the elasticity of human cardiomyocytes. We propose that posttranslational modification of cryptic residues is a general mechanism to regulate tissue elasticity.
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Affiliation(s)
| | - Pallav Kosuri
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA; Graduate Program in Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - David Giganti
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Edward Eckels
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA; Columbia College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | | | - Nazha Hamdani
- Department of Cardiovascular Physiology, Ruhr University Bochum, 44780 Bochum, Germany
| | - Chad M Warren
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - R John Solaro
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Wolfgang A Linke
- Department of Cardiovascular Physiology, Ruhr University Bochum, 44780 Bochum, Germany
| | - Julio M Fernández
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA.
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Oxidative stress in muscular dystrophy: from generic evidence to specific sources and targets. J Muscle Res Cell Motil 2014; 35:23-36. [PMID: 24619215 DOI: 10.1007/s10974-014-9380-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Accepted: 02/19/2014] [Indexed: 01/06/2023]
Abstract
Muscular dystrophies (MDs) are a heterogeneous group of diseases that share a common end-point represented by muscular wasting. MDs are caused by mutations in a variety of genes encoding for different molecules, including extracellular matrix, transmembrane and membrane-associated proteins, cytoplasmic enzymes and nuclear proteins. However, it is still to be elucidated how genetic mutations can affect the molecular mechanisms underlying the contractile impairment occurring in these complex pathologies. The intracellular accumulation of reactive oxygen species (ROS) is widely accepted to play a key role in contractile derangements occurring in the different forms of MDs. However, scarce information is available concerning both the most relevant sources of ROS and their major molecular targets. This review focuses on (i) the sources of ROS, with a special emphasis on monoamine oxidase, a mitochondrial enzyme, and (ii) the targets of ROS, highlighting the relevance of the oxidative modification of myofilament proteins.
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75
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Posch A, Kohn J, Oh K, Hammond M, Liu N. V3 stain-free workflow for a practical, convenient, and reliable total protein loading control in western blotting. J Vis Exp 2013:50948. [PMID: 24429481 DOI: 10.3791/50948] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The western blot is a very useful and widely adopted lab technique, but its execution is challenging. The workflow is often characterized as a "black box" because an experimentalist does not know if it has been performed successfully until the last of several steps. Moreover, the quality of western blot data is sometimes challenged due to a lack of effective quality control tools in place throughout the western blotting process. Here we describe the V3 western workflow, which applies stain-free technology to address the major concerns associated with the traditional western blot protocol. This workflow allows researchers: 1) to run a gel in about 20-30 min; 2) to visualize sample separation quality within 5 min after the gel run; 3) to transfer proteins in 3-10 min; 4) to verify transfer efficiency quantitatively; and most importantly 5) to validate changes in the level of the protein of interest using total protein loading control. This novel approach eliminates the need of stripping and reprobing the blot for housekeeping proteins such as β-actin, β-tubulin, GAPDH, etc. The V3 stain-free workflow makes the western blot process faster, transparent, more quantitative and reliable.
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76
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Pastore A, Piemonte F. Protein glutathionylation in cardiovascular diseases. Int J Mol Sci 2013; 14:20845-76. [PMID: 24141185 PMCID: PMC3821647 DOI: 10.3390/ijms141020845] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Revised: 10/02/2013] [Accepted: 10/08/2013] [Indexed: 02/07/2023] Open
Abstract
The perturbation of thiol-disulfide homeostasis is an important consequence of many diseases, with redox signals implicated in several physio-pathological processes. A prevalent form of cysteine modification is the reversible formation of protein mixed disulfides with glutathione (S-glutathionylation). The abundance of glutathione in cells and the ready conversion of sulfenic acids to S-glutathione mixed disulfides supports the reversible protein S-glutathionylation as a common feature of redox signal transduction, able to regulate the activities of several redox sensitive proteins. In particular, protein S-glutathionylation is emerging as a critical signaling mechanism in cardiovascular diseases, because it regulates numerous physiological processes involved in cardiovascular homeostasis, including myocyte contraction, oxidative phosphorylation, protein synthesis, vasodilation, glycolytic metabolism and response to insulin. Thus, perturbations in protein glutathionylation status may contribute to the etiology of many cardiovascular diseases, such as myocardial infarction, cardiac hypertrophy and atherosclerosis. Various reports show the importance of oxidative cysteine modifications in modulating cardiovascular function. In this review, we illustrate tools and strategies to monitor protein S-glutathionylation and describe the proteins so far identified as glutathionylated in myocardial contraction, hypertrophy and inflammation.
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Affiliation(s)
- Anna Pastore
- Laboratory of Biochemistry, Bambino Gesù Children’s Hospital, IRCCS, 00165 Rome, Italy; E-Mail:
| | - Fiorella Piemonte
- Unit of Neuromuscular and Neurodegenerative Diseases, Bambino Gesù Children’s Hospital, IRCCS, 00165 Rome, Italy
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77
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Katz A, Hernández A, Caballero DMR, Briceno JFB, Amezquita LVR, Kosterina N, Bruton JD, Westerblad H. Effects of N-acetylcysteine on isolated mouse skeletal muscle: contractile properties, temperature dependence, and metabolism. Pflugers Arch 2013; 466:577-85. [PMID: 23912895 DOI: 10.1007/s00424-013-1331-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 07/18/2013] [Accepted: 07/18/2013] [Indexed: 02/08/2023]
Abstract
The effects of the general antioxidant N-acetylcysteine (NAC) on muscle function and metabolism were examined. Isolated paired mouse extensor digitorum longus muscles were studied in the absence or presence of 20 mM NAC. Muscles were electrically stimulated to perform 100 isometric tetanic contractions (300 ms duration) at frequencies resulting in ∼85% of maximal force (70-150 Hz at 25-40 °C). NAC did not significantly affect peak force in the unfatigued state at any temperature but significantly slowed tetanic force development in a temperature-dependent fashion (e.g., time to 50% of peak tension averaged 35 ± 2 ms [control] and 37 ± 1 ms [NAC] at 25 °C vs. 21 ± 1 ms [control] and 52 ± 6 ms [NAC, P < 0.01] at 40 °C). During repeated contractions, NAC maximally enhanced peak force by the fifth tetanus at all temperatures (by ∼30%). Thereafter, the effect of NAC disappeared rapidly at high temperatures (35-40 °C) and more slowly at the lower temperatures (25-30 °C). At all temperatures, the enhancing effect of NAC on peak force was associated with a slowing of relaxation. NAC did not significantly affect myosin light chain phosphorylation at rest or after five contractions (∼50% increase vs. rest). After five tetani, lactate and inorganic phosphate increased about 20-fold and 2-fold, respectively, both in control and NAC-treated muscles. Interestingly, after five tetani, the increase in glucose 6-P was ∼2-fold greater, whereas the increase in malate was inhibited by ∼75% with NAC vs. control, illustrating the metabolic effects of NAC. NAC slightly decreased the maximum shortening velocity in early fatigue (five to seven repeated tetani). These data demonstrate that the antioxidant NAC transiently enhances muscle force generation by a mechanism that is independent of changes in myosin light chain phosphorylation and inorganic phosphate. The slowing of relaxation suggests that NAC enhances isometric force by facilitating fusion (i.e., delaying force decline between pulses). The initial slowing of tension development and subsequent slowing of relaxation suggest that NAC would result in impaired performance during a high-intensity dynamic exercise.
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Affiliation(s)
- Abram Katz
- Department of Physiology and Pharmacology, Karolinska Institutet, 17177, Stockholm, Sweden,
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Gross SM, Lehman SL. Accessibility of myofilament cysteines and effects on ATPase depend on the activation state during exposure to oxidants. PLoS One 2013; 8:e69110. [PMID: 23894416 PMCID: PMC3716824 DOI: 10.1371/journal.pone.0069110] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Accepted: 06/05/2013] [Indexed: 11/28/2022] Open
Abstract
Signaling by reactive oxygen species has emerged as a major physiological process. Due to its high metabolic rate, striated muscle is especially subject to oxidative stress, and there are multiple examples in cardiac and skeletal muscle where oxidative stress modulates contractile function. Here we assessed the potential of cysteine oxidation as a mechanism for modulating contractile function in skeletal and cardiac muscle. Analyzing the cysteine content of the myofilament proteins in striated muscle, we found that cysteine residues are relatively rare, but are very similar between different muscle types and different vertebrate species. To refine this list of cysteines to those that may modulate function, we estimated the accessibility of oxidants to cysteine residues using protein crystal structures, and then sharpened these estimates using fluorescent labeling of cysteines in cardiac and skeletal myofibrils. We demonstrate that cysteine accessibility to oxidants and ATPase rates depend on the contractile state in which preparations are exposed. Oxidant exposure of skeletal and cardiac myofibrils in relaxing solution exposes myosin cysteines not accessible in rigor solution, and these modifications correspond to a decrease in maximum ATPase. Oxidant exposure under rigor conditions produces modifications that increase basal ATPase and calcium sensitivity in ventricular myofibrils, but these effects were muted in fast twitch muscle. These experiments reveal how structural and sequence variations can lead to divergent effects from oxidants in different muscle types.
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Affiliation(s)
- Sean M. Gross
- Department of Integrative Biology, University of California, Berkeley, California, United States of America
| | - Steven L. Lehman
- Department of Integrative Biology, University of California, Berkeley, California, United States of America
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79
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Hvid LG, Gejl K, Bech RD, Nygaard T, Jensen K, Frandsen U, Ørtenblad N. Transient impairments in single muscle fibre contractile function after prolonged cycling in elite endurance athletes. Acta Physiol (Oxf) 2013; 208:265-73. [PMID: 23480612 DOI: 10.1111/apha.12095] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 02/28/2013] [Accepted: 03/05/2013] [Indexed: 11/27/2022]
Abstract
AIM Prolonged muscle activity impairs whole-muscle performance and function. However, little is known about the effects of prolonged muscle activity on the contractile function of human single muscle fibres. The purpose of this study was to investigate the effects of prolonged exercise and subsequent recovery on the contractile function of single muscle fibres obtained from elite athletes. METHODS Nine male triathletes (26 ± 1 years, 68 ± 1 mL O2 min(-1) kg(-1) , training volume 16 ± 1 h week(-1) ) performed 4 h of cycling exercise (at 73% of HRmax ) followed by 24 h of recovery. Biopsies from vastus lateralis were obtained before and following 4 h exercise and following 24 h recovery. Measurements comprised maximal Ca(2+) -activated specific force and Ca(2+) sensitivity of slow type I and fast type II single muscle fibres, as well as cycling peak power output. RESULTS Following cycling exercise, specific force was reduced to a similar extent in slow and fast fibres (-15 and -18%, respectively), while Ca(2+) sensitivity decreased in fast fibres only. Single fibre-specific force was fully restored in both fibre types after 24 h recovery. Cycling peak power output was reduced by 4-9% following cycling exercise and fully restored following recovery. CONCLUSION This is the first study to demonstrate that prolonged cycling exercise transiently impairs specific force in type I and II fibres and decreases Ca(2+) sensitivity in type II fibres only, specifically in elite endurance athletes. Further, the changes in single fibre-specific force induced by exercise and recovery coincided temporally with changes in cycling peak power output.
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Affiliation(s)
- L. G. Hvid
- Institute of Sports Science and Clinical Biomechanics, SDU Muscle Research Cluster (SMRC); Institute of Sports Science and Clinical Biomechanics; University of Southern Denmark; Odense; Denmark
| | - K. Gejl
- Institute of Sports Science and Clinical Biomechanics, SDU Muscle Research Cluster (SMRC); Institute of Sports Science and Clinical Biomechanics; University of Southern Denmark; Odense; Denmark
| | - R. D. Bech
- Department of Orthopaedic Surgery; Odense University Hospital; Odense; Denmark
| | - T. Nygaard
- Department of Orthopaedic Surgery; Rigshospitalet; University of Copenhagen; Copenhagen; Denmark
| | - K. Jensen
- Institute of Sports Science and Clinical Biomechanics, SDU Muscle Research Cluster (SMRC); Institute of Sports Science and Clinical Biomechanics; University of Southern Denmark; Odense; Denmark
| | - U. Frandsen
- Institute of Sports Science and Clinical Biomechanics, SDU Muscle Research Cluster (SMRC); Institute of Sports Science and Clinical Biomechanics; University of Southern Denmark; Odense; Denmark
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80
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Allen DG. Dynamic changes in the contractile apparatus during exercise. Acta Physiol (Oxf) 2013; 208:220-1. [PMID: 23614972 DOI: 10.1111/apha.12109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- D. G. Allen
- School of Medical Sciences; University of Sydney; Sydney; NSW; Australia
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81
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Li R, Shen Y. An old method facing a new challenge: re-visiting housekeeping proteins as internal reference control for neuroscience research. Life Sci 2013; 92:747-51. [PMID: 23454168 DOI: 10.1016/j.lfs.2013.02.014] [Citation(s) in RCA: 124] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 02/08/2013] [Accepted: 02/18/2013] [Indexed: 01/09/2023]
Abstract
The study of specific target protein expression is often performed by western blotting, a commonly used method to measure the protein expression in neuroscience research by specific antibodies. Housekeeping proteins are used as an internal control for protein loading as well as reference in the western blotting analysis. This practice is based on the belief that such housekeeping genes are considered to be ubiquitously and constitutively expressed in every tissue and produce the minimal essential transcripts necessary for normal cellular function. The most commonly used housekeeping proteins are β-actin, β-tubulin, and glyceraldehyde 3-phosphate dehydrogenase (GAPDH). However, recent studies have shown significant variation in some housekeeping genes both at the mRNA and protein levels in various neuropathological events, such as spinal cord injury and Alzheimer's diseases. Changes of housekeeping genes are also induced by non-neuronal diseases in various tissues. Therefore, these discoveries raise a potential concern regarding whether using a housekeeping protein as an internal standard for target protein analysis is an appropriate practice. This minireview will focus on (I) the effects of neuronal and non-neuronal diseases, experimental condition, and tissue-specific roles on alteration of housekeeping genes, and (II) alternative internal standards for gene and protein expression analysis.
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Affiliation(s)
- Rena Li
- Center for Hormone Advanced Science and Education, Roskamp Institute, Sarasota, FL 34243, USA.
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82
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Terrill JR, Radley-Crabb HG, Iwasaki T, Lemckert FA, Arthur PG, Grounds MD. Oxidative stress and pathology in muscular dystrophies: focus on protein thiol oxidation and dysferlinopathies. FEBS J 2013; 280:4149-64. [PMID: 23332128 DOI: 10.1111/febs.12142] [Citation(s) in RCA: 130] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 01/14/2013] [Accepted: 01/15/2013] [Indexed: 12/23/2022]
Abstract
The muscular dystrophies comprise more than 30 clinical disorders that are characterized by progressive skeletal muscle wasting and degeneration. Although the genetic basis for many of these disorders has been identified, the exact mechanism for pathogenesis generally remains unknown. It is considered that disturbed levels of reactive oxygen species (ROS) contribute to the pathology of many muscular dystrophies. Reactive oxygen species and oxidative stress may cause cellular damage by directly and irreversibly damaging macromolecules such as proteins, membrane lipids and DNA; another major cellular consequence of reactive oxygen species is the reversible modification of protein thiol side chains that may affect many aspects of molecular function. Irreversible oxidative damage of protein and lipids has been widely studied in Duchenne muscular dystrophy, and we have recently identified increased protein thiol oxidation in dystrophic muscles of the mdx mouse model for Duchenne muscular dystrophy. This review evaluates the role of elevated oxidative stress in Duchenne muscular dystrophy and other forms of muscular dystrophies, and presents new data that show significantly increased protein thiol oxidation and high levels of lipofuscin (a measure of cumulative oxidative damage) in dysferlin-deficient muscles of A/J mice at various ages. The significance of this elevated oxidative stress and high levels of reversible thiol oxidation, but minimal myofibre necrosis, is discussed in the context of the disease mechanism for dysferlinopathies, and compared with the situation for dystrophin-deficient mdx mice.
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Affiliation(s)
- Jessica R Terrill
- School of Anatomy, Physiology and Human Biology, University of Western Australia, Perth, Western Australia, Australia
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83
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Allen DG, Trajanovska S. The multiple roles of phosphate in muscle fatigue. Front Physiol 2012; 3:463. [PMID: 23248600 PMCID: PMC3518787 DOI: 10.3389/fphys.2012.00463] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 11/22/2012] [Indexed: 01/23/2023] Open
Abstract
Muscle fatigue is the decline in performance of muscles observed during periods of intense activity. ATP consumption exceeds production during intense activity and there are multiple changes in intracellular metabolites which may contribute to the changes in crossbridge activity. It is also well-established that a reduction in activation, either through action potential changes or reduction in Ca(2+) release from the sarcoplasmic reticulum (SR), makes an additional contribution to fatigue. In this review we focus on the role of intracellular inorganic phosphate (P(i)) whose concentration can increase rapidly from around 5-30 mM during intense fatigue. Studies from skinned muscle fibers show that these changes substantially impair myofibrillar performance although the effects are strongly temperature dependent. Increased P(i) can also cause reduced Ca(2+) release from the SR and may therefore contribute to the reduced activation. In a recent study, we have measured both P(i) and Ca(2+) release in a blood-perfused mammalian preparation and the results from this preparation allows us to test the extent to which the combined effects of P(i) and Ca(2+) changes may contribute to fatigue.
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Affiliation(s)
- David G Allen
- School of Medical Sciences, Bosch Institute and Sydney School of Medicine, University of Sydney Sydney, NSW, Australia
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84
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Dutka TL, Mollica JP, Posterino GS, Lamb GD. Reply from T. L. Dutka, J. P. Mollica, G. S. Posterino and G. D. Lamb. J Physiol 2012. [DOI: 10.1113/jphysiol.2012.243964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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