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• W2049951278 abstract "Activin A, a member of the transforming growth factor-β superfamily, provides pleiotropic regulation of fibrosis and inflammation. We aimed at determining whether selective inhibition of activin A would provide a regenerative benefit. The introduction of activin A into normal muscle increased the expression of inflammatory and muscle atrophy genes Tnf, Tnfrsf12a, Trim63, and Fbxo32 by 3.5-, 10-, 2-, and 4-fold, respectively. The data indicate a sensitive response of muscle to activin A. Two hours after cardiotoxin-induced muscle damage, local activin A protein expression increased by threefold to ninefold. Neutralization of activin A with a specific monoclonal antibody in this muscle injury model decreased the muscle protein levels of lymphotoxin α and Il17a by 32% and 42%, respectively. Muscle histopathological features showed that activin A antibody–treated mice displayed an increase in muscle degradation, with the concomitant 9.2-fold elevation in F4/80-positive cells 3 days after injury. At the same time, the number of Pax7/Myod1-positive cells also increased, indicative of potentiated muscle precursor activation. Ultimately, activin A inhibition resulted in rapid recovery of muscle contractile properties indicated by a restoration of maximum and specific force. In summary, selective inhibition of activin A with a monoclonal antibody in muscle injury leads to the early onset of tissue degradation and subsequent enhanced myogenesis, thereby accelerating muscle repair and functional recovery. Activin A, a member of the transforming growth factor-β superfamily, provides pleiotropic regulation of fibrosis and inflammation. We aimed at determining whether selective inhibition of activin A would provide a regenerative benefit. The introduction of activin A into normal muscle increased the expression of inflammatory and muscle atrophy genes Tnf, Tnfrsf12a, Trim63, and Fbxo32 by 3.5-, 10-, 2-, and 4-fold, respectively. The data indicate a sensitive response of muscle to activin A. Two hours after cardiotoxin-induced muscle damage, local activin A protein expression increased by threefold to ninefold. Neutralization of activin A with a specific monoclonal antibody in this muscle injury model decreased the muscle protein levels of lymphotoxin α and Il17a by 32% and 42%, respectively. Muscle histopathological features showed that activin A antibody–treated mice displayed an increase in muscle degradation, with the concomitant 9.2-fold elevation in F4/80-positive cells 3 days after injury. At the same time, the number of Pax7/Myod1-positive cells also increased, indicative of potentiated muscle precursor activation. Ultimately, activin A inhibition resulted in rapid recovery of muscle contractile properties indicated by a restoration of maximum and specific force. In summary, selective inhibition of activin A with a monoclonal antibody in muscle injury leads to the early onset of tissue degradation and subsequent enhanced myogenesis, thereby accelerating muscle repair and functional recovery. Activin A and myostatin (Mstn) are transforming growth factor (TGF)-β receptor ligands and are part of a large family of proteins implicated to play critical roles in embryonic development through adulthood.1Massague J. TGFbeta signalling in context.Nat Rev Mol Cell Biol. 2012; 13: 616-630Crossref PubMed Scopus (2040) Google Scholar Extensive research has been reported on the role of Mstn in controlling muscle mass gain. Many laboratories have demonstrated that blocking Mstn signaling, by a variety of genetic and pharmacological modes, results in the improvement of disease features in mouse models of muscular dystrophy and injury.2Bartoli M. Poupiot J. Vulin A. Fougerousse F. Arandel L. Daniele N. Roudaut C. Noulet F. Garcia L. Danos O. Richard I. AAV-mediated delivery of a mutated myostatin propeptide ameliorates calpain 3 but not alpha-sarcoglycan deficiency.Gene Ther. 2007; 14: 733-740Crossref PubMed Scopus (73) Google Scholar, 3Bogdanovich S. Krag T.O. Barton E.R. Morris L.D. Whittemore L.A. Ahima R.S. Khurana T.S. Functional improvement of dystrophic muscle by myostatin blockade.Nature. 2002; 420: 418-421Crossref PubMed Scopus (699) Google Scholar, 4Ohsawa Y. Hagiwara H. Nakatani M. Yasue A. Moriyama K. Murakami T. Tsuchida K. Noji S. Sunada Y. Muscular atrophy of caveolin-3-deficient mice is rescued by myostatin inhibition.J Clin Invest. 2006; 116: 2924-2934Crossref PubMed Scopus (93) Google Scholar, 5Parsons S.A. Millay D.P. Sargent M.A. McNally E.M. Molkentin J.D. Age-dependent effect of myostatin blockade on disease severity in a murine model of limb-girdle muscular dystrophy.Am J Pathol. 2006; 168: 1975-1985Abstract Full Text Full Text PDF PubMed Scopus (81) Google Scholar, 6Qiao C. Li J. Jiang J. Zhu X. Wang B. Xiao X. Myostatin propeptide gene delivery by adeno-associated virus serotype 8 vectors enhances muscle growth and ameliorates dystrophic phenotypes in mdx mice.Hum Gene Ther. 2008; 19: 241-254Crossref PubMed Scopus (125) Google Scholar, 7Wagner K.R. Liu X. Chang X. Allen R.E. Muscle regeneration in the prolonged absence of myostatin.Proc Natl Acad Sci U S A. 2005; 102: 2519-2524Crossref PubMed Scopus (163) Google Scholar Satellite cells are the resident stem cells located between the sarcolemma and basal lamina of the myofiber and are responsible for the facilitation of muscle restoration after injury.8McFarlane C. Hennebry A. Thomas M. Plummer E. Ling N. Sharma M. Kambadur R. Myostatin signals through Pax7 to regulate satellite cell self-renewal.Exp Cell Res. 2008; 314: 317-329Crossref PubMed Scopus (117) Google Scholar, 9McCroskery S. Thomas M. Maxwell L. Sharma M. Kambadur R. Myostatin negatively regulates satellite cell activation and self-renewal.J Cell Biol. 2003; 162: 1135-1147Crossref PubMed Scopus (564) Google Scholar A role for Mstn has also been suggested because of its ability to interfere with the activation of satellite cells to impede muscle growth and repair. Mstn has been shown to be a negative regulator of satellite cell expansion via modulation of Pax7 and Myod1 expression, as well as key cell cycle control factors, such as Cdkn1a and Cdk2, in proliferating satellite and myoblast cells. Although Mstn is generally accepted to be the master regulator of muscle homeostasis, scant evidence exists for other regulatory factors that may have direct roles in skeletal muscle.10McPherron A.C. Lawler A.M. Lee S.J. Regulation of skeletal muscle mass in mice by a new TGF-beta superfamily member.Nature. 1997; 387: 83-90Crossref PubMed Scopus (3066) Google Scholar One of these factors is activin A, which belongs to the activin family (ie, composed of many members that are formed from the following subunits: βA, βB, βC, and βE).11Mellor S.L. Cranfield M. Ries R. Pedersen J. Cancilla B. de Kretser D. Groome N.P. Mason A.J. Risbridger G.P. Localization of activin beta(A)-, beta(B)-, and beta(C)-subunits in human prostate and evidence for formation of new activin heterodimers of beta(C)-subunit.J Clin Endocrinol Metab. 2000; 85: 4851-4858PubMed Scopus (0) Google Scholar, 12Mellor S.L. Ball E.M. O’Connor A.E. Ethier J.F. Cranfield M. Schmitt J.F. Phillips D.J. Groome N.P. Risbridger G.P. Activin betaC-subunit heterodimers provide a new mechanism of regulating activin levels in the prostate.Endocrinology. 2003; 144: 4410-4419Crossref PubMed Scopus (55) Google Scholar, 13Burger H.G. McLachlan R.I. Bangah M. Quigg H. Findlay J.K. Robertson D.M. de Kretser D.M. Warne G.L. Werther G.A. Hudson I.L. Cook J.J. Fiedler R. Greco S. Yong A.B.W. Smith P. Serum inhibin concentrations rise throughout normal male and female puberty.J Clin Endocrinol Metab. 1988; 67: 689-694Crossref PubMed Scopus (61) Google Scholar Activin A is a disulphide-linked dimer containing two of the previously mentioned β-subunits, where it can bind and elicit a response through binding with the activin receptors IIA and IIB (Acvr2a/2b) that mediate its diverse behavior.14Huylebroeck D. Van Nimmen K. Waheed A. von Figura K. Marmenout A. Fransen L. De Waele P. Jaspar J.M. Franchimont P. Stunnenberg H. Van Heuverswijn H. Expression and processing of the activin-A/erythroid differentiation factor precursor: a member of the transforming growth factor-beta superfamily.Mol Endocrinol. 1990; 4: 1153-1165Crossref PubMed Scopus (28) Google Scholar, 15Gray A.M. Mason A.J. Requirement for activin A and transforming growth factor–beta 1 pro-regions in homodimer assembly.Science. 1990; 247: 1328-1330Crossref PubMed Scopus (217) Google Scholar, 16Attisano L. Wrana J.L. Cheifetz S. Massague J. Novel activin receptors: distinct genes and alternative mRNA splicing generate a repertoire of serine/threonine kinase receptors.Cell. 1992; 68: 97-108Abstract Full Text PDF PubMed Scopus (450) Google Scholar This pleiotropic activity of activin A has led to its purported role in the etiologies of multiple diseases, ranging from cancer-metastasis to osteoporosis.17Leto G. Activin A and bone metastasis.J Cell Physiol. 2010; 225: 302-309Crossref PubMed Scopus (17) Google Scholar, 18Leto G. Incorvaia L. Badalamenti G. Tumminello F.M. Gebbia N. Flandina C. Crescimanno M. Rini G. Activin A circulating levels in patients with bone metastasis from breast or prostate cancer.Clin Exp Metastasis. 2006; 23: 117-122Crossref PubMed Scopus (94) Google Scholar, 19Lotinun S. Pearsall R.S. Davies M.V. Marvell T.H. Monnell T.E. Ucran J. Fajardo R.J. Kumar R. Underwood K.W. Seehra J. Bouxsein M.L. Baron R. A soluble activin receptor Type IIA fusion protein (ACE-011) increases bone mass via a dual anabolic-antiresorptive effect in Cynomolgus monkeys.Bone. 2010; 46: 1082-1088Abstract Full Text Full Text PDF PubMed Scopus (112) Google Scholar, 20Terpos E. Kastritis E. Christoulas D. Gkotzamanidou M. Eleutherakis-Papaiakovou E. Kanellias N. Papatheodorou A. Dimopoulos M.A. Circulating activin-A is elevated in patients with advanced multiple myeloma and correlates with extensive bone involvement and inferior survival: no alterations post-lenalidomide and dexamethasone therapy.Ann Oncol. 2012; 23: 2681-2686Crossref PubMed Scopus (83) Google Scholar, 21Fajardo R.J. Manoharan R.K. Pearsall R.S. Davies M.V. Marvell T. Monnell T.E. Ucran J.A. Pearsall A.E. Khanzode D. Kumar R. Underwood K.W. Roberts B. Seehra J. Bouxsein M.L. Treatment with a soluble receptor for activin improves bone mass and structure in the axial and appendicular skeleton of female cynomolgus macaques (Macaca fascicularis).Bone. 2010; 46: 64-71Abstract Full Text Full Text PDF PubMed Scopus (59) Google Scholar The first report indicating a role for activin A in skeletal muscle could be on the basis of data from Lee,22Lee S.J. Quadrupling muscle mass in mice by targeting TGF-beta signaling pathways.PLoS One. 2007; 2: e789Crossref PubMed Scopus (247) Google Scholar who identified the existence of an additional muscle regulator by crossing Mstn-null mice with mice carrying a follistatin transgene that promoted additional gain in muscle mass. Follistatin has been shown to be a potent inhibitor of activin A, which has been established as an inducer of muscle atrophy when exclusively overexpressed in healthy muscle via electroporation and indirectly through overexpressing activin A tumors.23Zhou X. Wang J.L. Lu J. Song Y. Kwak K.S. Jiao Q. Rosenfeld R. Chen Q. Boone T. Simonet W.S. Lacey D.L. Goldberg A.L. Han H.Q. Reversal of cancer cachexia and muscle wasting by ActRIIB antagonism leads to prolonged survival.Cell. 2010; 142: 531-543Abstract Full Text Full Text PDF PubMed Scopus (664) Google Scholar, 24Gilson H. Schakman O. Kalista S. Lause P. Tsuchida K. Thissen J.P. Follistatin induces muscle hypertrophy through satellite cell proliferation and inhibition of both myostatin and activin.Am J Physiol Endocrinol Metab. 2009; 297: E157-E164Crossref PubMed Scopus (171) Google Scholar These results, albeit in a less robust manner, were recapitulated in a separate study using a transgenic that specifically overexpressed the extracellular domain of the Acvr2b.25Lee S.J. McPherron A.C. Regulation of myostatin activity and muscle growth.Proc Natl Acad Sci U S A. 2001; 98: 9306-9311Crossref PubMed Scopus (1234) Google Scholar Activins have been described as possessing both inflammatory and anti-inflammatory activities and are key regulators of the cytokine cascade that initiates the inflammatory response.26Jones K.L. Mansell A. Patella S. Scott B.J. Hedger M.P. de Kretser D.M. Phillips D.J. Activin A is a critical component of the inflammatory response, and its binding protein, follistatin, reduces mortality in endotoxemia.Proc Natl Acad Sci U S A. 2007; 104: 16239-16244Crossref PubMed Scopus (207) Google Scholar, 27Phillips D.J. de Kretser D.M. Hedger M.P. Activin and related proteins in inflammation: not just interested bystanders.Cytokine Growth Factor Rev. 2009; 20: 153-164Abstract Full Text Full Text PDF PubMed Scopus (132) Google Scholar The inflammatory response is a key driver in soft tissue repair and muscle injury, although its sustained expression can impede tissue regeneration, resulting in fibrosis or scar formation.28Fumagalli M. Musso T. Vermi W. Scutera S. Daniele R. Alotto D. Cambieri I. Ostorero A. Gentili F. Caposio P. Zucca M. Sozzani S. Stella M. Castagnoli C. Imbalance between activin A and follistatin drives postburn hypertrophic scar formation in human skin.Exp Dermatol. 2007; 16: 600-610Crossref PubMed Scopus (43) Google Scholar These attributes of activin and associated biological features are consistent with a role in muscle injury, specifically, inflammation, macrophage regulation, muscle growth, and repair. However, it is typically assumed that activin A plays a direct role in skeletal muscle. Therefore, understanding activin’s role in inflammation after traumatic injury is essential in delineating a mechanism on how soft tissues may recover from such injury. Coupled with activin A’s role in healthy muscle tissue, to our knowledge, no reports exist on its direct role in the context of disease, particularly in muscle injury. Therefore, the primary goal of this study was to further investigate if selective inhibition of activin A, in both normal adult mouse and injured skeletal muscle tissue, would provide a regenerative benefit. As described herein, our findings confirm a critical role for endogenous activin A, by showing a time-dependent increase in protein levels shortly after muscle injury. Furthermore, local sustained overexpression of activin A, in the context of a normal muscle using target gene electroporation, results in a degeneration of muscle tissue, which is more pronounced than that observed with MSTN overexpression. In the context of muscle injury, selective inhibition of activin A using a monoclonal antibody led to a dramatic and rapid reduction in pathological conditions associated with muscle injury and damage that ultimately improved muscle function. Finally, our data suggest that these effects are accomplished via modulation of the early inflammatory response. We hypothesize that this modulation results in more efficient remodeling of the degenerative tissue resulting from activated macrophages, as evidenced by the changes in F4/80, leading to accelerated myogenesis, as measured by an increase in Pax7-positive cells. Most notably, the resultant muscle is more capable of producing normal muscle function. The results presented in this study reveal that increases in muscle-derived activin A play a deleterious role in skeletal muscle recovery after injury and are a critical contributor to muscle degeneration, which, when neutralized, can result in accelerated muscle repair. All mouse experiments were performed with the approval of Eli Lilly & Company’s Institutional Animal Care and Use Committee and are in accordance with the NIH Guide for the Care and Use of Laboratory Animals. For all studies described herein, 10-week-old C57BL/6 female mice were used (Harlan, Indianapolis, IN). Animals were housed in a room with controlled temperature (22°C ± 2°C) and a 12-hour light-dark cycle, with ad lib access to food and water. C2C12 (CRL-1772; ATCC, Manassas, VA) was cultured in proliferation medium, Dulbecco’s modified Eagle’s medium (Lonza, Basel, Switzerland), supplemented with 10% fetal bovine serum (Gibco, Invitrogen, Carlsbad, CA), 4.5 g/L glucose, 100 U/mL penicillin, 100 mg/mL streptomycin, 1 mmol/L sodium pyruvate, and 2 mmol/L l-glutamine (BioWhittaker, Walkersville, MD). Myotube formation was induced by introduction of 2% horse serum (Biochrom-Seromed, Paris, France) in the medium. Controls used in the cell-based assays were either murine (m)IgG1 or bovine serum albumin (BSA). All in vitro experiments were repeated three times. A mouse monoclonal antibody that recognizes myosin heavy chain (MHC; MAB4470; R&D Systems, Minneapolis, MN) was used to evaluate myotube formation in differentiated C2C12 cells treated with either vehicle or recombinant lymphotoxin α (Lta; R&D Systems). Cells were fixed in 10% formalin overnight and permeabilized in 0.25% Triton X-100 (Sigma-Aldrich, St. Louis, MO) in PBS. Cells were then incubated with 8 μg/mL MHC antibody overnight at 4°C, followed by incubation with a secondary antibody, Alexa 488–conjugated antibodies (1:1000; Invitrogen), for 1 hour at room temperature. ATP was measured in C2C12 myotubes using the commercially available CellTiter-Glo Luminescent Cell Viability Assay kit from Promega (Madison, WI). All plasmids were constructed by inserting the cDNAs into the CAG expression vector (InvivoGen, San Diego, CA). DNA for all in vivo experiments was prepared using the Qiagen ENDO-Free Maxi prep kit (Qiagen, Valencia, CA). DNA was eluted into saline at a concentration of 0.5 μg/μL. Legs were shaved and then percutaneously injected with 25 μg of cDNA. After the injection of the cDNA, four pulses of 160 V/cm for a 0.1-millisecond duration at a 100-millisecond interval were delivered transcutaneously to the limb at a rate of one pulse per second with a BTX 830M electroporator (Harvard Apparatus, Holliston, MA) using gene calipers. All electroporation experiments included five animals per group and were repeated a minimum of four times. Cardiotoxin injury was performed similar to what was described by Garry et al,29Garry D.J. Meeson A. Elterman J. Zhao Y. Yang P. Bassel-Duby R. Williams R.S. Myogenic stem cell function is impaired in mice lacking the forkhead/winged helix protein MNF.Proc Natl Acad Sci U S A. 2000; 97: 5416-5421Crossref PubMed Scopus (129) Google Scholar with slight modifications. Muscle injury was induced by a 100-μL injection of a 10 μmol/L cardiotoxin (CTX; naja naja atra; Sigma-Aldrich part C3987) solution into the right gastrocnemius muscle, with a three-point injection technique, to fully cover the lateral and medial gastrocnemius. Experiments were performed in triplicate, and each study incorporated an uninjured (no CTX or treatment) control group as a reference. Muscle lysates were generated using 1 mL/100 mg of tissue in lysis buffer (Cell Signaling Technologies, Danvers, MA). Samples underwent a treatment with 10 mmol/L dithiothreitol in PBS for 1 hour at room temperature before plating. Antibody was coated and reconstituted in PBS at a final concentration of 100 μg/mL (AF338; R&D Systems). Antibody (100 μL per well) was diluted to 1 μg/mL in coating buffer (SH30256.01; Hyclone, Waltham, MA), incubated for 1 hour at 37°C and blocked for 1 hour; then, samples were incubated at room temperature for 1 hour. Polystreptavidin–horseradish peroxidase and 3,3′,5,5′-tetramethylbenzidine block steps were performed, and plates were read at 450 to 630 nmol/L. The enzyme-linked immunosorbent assay (ELISA) was validated using purified activin A protein. Muscle tissue was evaluated using H&E and Masson’s trichrome, and immunolabeled using anti-mouse F4/80 clone BM8 (eBiosicences, San Diego, CA) at 0.5 or 0.1 μg/mL anti-Pax 7 (Abcam, San Francisco, CA). Images were acquired using digital slide scanning (ScanScope XT; Aperio, Vista, CA). Immunofluorescence experiments were performed with Pax7 and Myod1 primary antibodies conjugated with a fluorescent label via the Alexa Fluor 488 protein labeling kit (Invitrogen) for Pax7 (1.0 μg/mL; Abcam) and the Alexa Fluor 633 protein labeling kit for Myod1 (0.1 μg/mL; Abcam) antibodies. DAPI staining was performed using Flouro-gel II with DAPI (Electron Microscopy Sciences, Hatfield, PA) during the coverslip process. All experiments were repeated for a minimum of three times with at least five animals per group. RNA was extracted from isolated muscles using TRIzol reagent (Life Technologies, Grand Island, NY). Total RNAs were reverse transcribed using the High Capacity cDNA Archive Kit (Applied Biosystems, Foster City, CA). All cDNAs were assayed for genes of interest using TaqMan Gene Expression Analysis (Applied Biosystems) and the Assay-On-Demand primer/probe set. Gene of interest mRNA levels were quantitated by determining the cycle number. Biological samples were subjected to quantitative PCR using the ABI 7900HT Real-Time PCR System (Applied Biosystems). All in situ muscle function experiments were performed using the 807B in situ small animal apparatus from Aurora Scientific (Aurora, ON, Canada), and experiments were repeated to confirm findings. Randomization into three equivalent groups of mice (n = 8 per group) was performed on the basis of body weight before the induction of injury. The foot was secured in the foot pedal, and two platinum electrodes were then inserted to stimulate the tibial nerve. Contractions of the gastrocnemius were induced by direct stimulation via the tibial nerve, and single twitches (rectangular pulse, 1 millisecond) were applied at different muscle lengths to determine the optimal length (resting length), measured with calipers as the distance between the medial condyle of the femur and the myotendinous junction near the calcaneus. Finally, the muscle was subjected to strength measurements, with external stimulation applied. The stimulation protocol was evaluated and optimized by stimulating the plantar-flexor muscle groups with trains of 0.1-millisecond square pulses at different pulse frequencies (5 to 150 Hz), train intervals, and current amplitudes. There were 60 seconds in between stimulations. A 50-millisecond train of 2.5-mA pulses at 100 Hz (five pulses per train) produced intense and forceful muscle contractions. Specific force was calculated by dividing the force generated at each frequency by muscle mass and cross-sectional area (CSA), as determined by Burkholder et al.30Burkholder T.J. Fingado B. Baron S. Lieber R.L. Relationship between muscle fiber types and sizes and muscle architectural properties in the mouse hindlimb.J Morphol. 1994; 221: 177-190Crossref PubMed Scopus (354) Google Scholar The formula to calculate the gastrocnemius bundle CSA is calculated from muscle weight and muscle length:CSA=MW×cos(25×pi/180)/1.056/0.45/ML/1000.(1) 30Burkholder T.J. Fingado B. Baron S. Lieber R.L. Relationship between muscle fiber types and sizes and muscle architectural properties in the mouse hindlimb.J Morphol. 1994; 221: 177-190Crossref PubMed Scopus (354) Google Scholar All results were expressed as means ± SEM. Significance (P ≤ 0.05) of the effects of activin A antibody treatment on various parameters was analyzed by one-way analysis of variance and Student’s t-test. We investigated the regulation of muscle-derived activin A in the context of muscle injury and repair. Because of activin A’s role in inflammation, we anticipated that changes in the tissue levels of activin A may be coincidental with the early inflammatory/degenerative phases.26Jones K.L. Mansell A. Patella S. Scott B.J. Hedger M.P. de Kretser D.M. Phillips D.J. Activin A is a critical component of the inflammatory response, and its binding protein, follistatin, reduces mortality in endotoxemia.Proc Natl Acad Sci U S A. 2007; 104: 16239-16244Crossref PubMed Scopus (207) Google Scholar To investigate this early regulation in activin A, gastrocnemius muscles were subjected to local CTX injections that result in focal injury. After the injections, muscle and blood samples were collected from 1 to 24 hours after injury and analyzed using ELISA. CTX venom was chosen as a model because it recapitulates the specific pathological condition observed in muscle injury such as trauma and surgery (namely, inflammation, tissue necrosis, macrophage infiltration, and satellite cell activation).31Charge S.B. Rudnicki M.A. Cellular and molecular regulation of muscle regeneration.Physiol Rev. 2004; 84: 209-238Crossref PubMed Scopus (1926) Google Scholar, 32Garry D.J. Yang Q. Bassel-Duby R. Williams R.S. Persistent expression of MNF identifies myogenic stem cells in postnatal muscles.Dev Biol. 1997; 188: 280-294Crossref PubMed Scopus (104) Google Scholar, 33Prisk V. Huard J. Muscle injuries and repair: the role of prostaglandins and inflammation.Histol Histopathol. 2003; 18: 1243-1256PubMed Google Scholar, 34Huard J. Li Y. Fu F.H. Muscle injuries and repair: current trends in research.J Bone Joint Surg Am. 2002; 84-A: 822-832Crossref PubMed Scopus (484) Google Scholar ELISA data clearly demonstrate that total activin A levels peaked at approximately 8 hours (approximately ninefold increase over background), and were maintained for up to 24 hours (Figure 1A); however, these changes did not influence the serum activin A levels. In contrast, residual injury due to injections with PBS alone did not increase muscle activin A levels (Figure 1B). These findings reveal an important tissue-level activation of muscle-derived activin A that parallels early inflammatory and/or the resultant degenerative cascade as a result of CTX injury. Because CTX-mediated focal injury increased muscle levels of activin A, we wanted to test the direct consequence of increasing activin A levels in muscle tissue using in vivo electroporation of expression plasmids containing open reading frames corresponding to activin A. We then compared it with the other TGF-β ligands, such as Mstn and Gdf11, in normal muscle. Each animal was intramuscularly injected with 25 μg of either empty vector control or the molar equivalents of the previously mentioned TGF-β family members and subjected to electroporation, similar to methods produced by Yin and Tang35Yin D. Tang J.G. Gene therapy for streptozotocin-induced diabetic mice by electroporational transfer of naked human insulin precursor DNA into skeletal muscle in vivo.FEBS Lett. 2001; 495: 16-20Crossref PubMed Scopus (57) Google Scholar and Kawai et al,36Kawai M. Bessho K. Maruyama H. Miyazaki J. Yamamoto T. Simultaneous gene transfer of bone morphogenetic protein (BMP)-2 and BMP-7 by in vivo electroporation induces rapid bone formation and BMP-4 expression.BMC Musculoskelet Disord. 2006; 7: 62Crossref PubMed Scopus (52) Google Scholar but with slight modifications. Tissues were harvested at the end of the 25-day period to assess the ligands’ effect on muscle mass. Gross observation of the excised gastrocnemius in activin A–treated animals clearly demonstrated a reduction in size and mass relative to the empty vector control-treated animals (Figure 1C). MSTN overexpression resulted in significant muscle atrophy (18.6%) and was comparable to what has been previously reported in other studies,37Durieux A.C. Amirouche A. Banzet S. Koulmann N. Bonnefoy R. Pasdeloup M. Mouret C. Bigard X. Peinnequin A. Freyssenet D. Ectopic expression of myostatin induces atrophy of adult skeletal muscle by decreasing muscle gene expression.Endocrinology. 2007; 148: 3140-3147Crossref PubMed Scopus (114) Google Scholar whereas GDF11 (6.4%) did not produce a significant change in muscle wet weight (Figure 1D). However, activin A overexpression produced a dramatic 52% reduction in muscle mass. These differential changes in muscle mass due to overexpression of these TGF-β members did not appear to be related to their relative mRNA levels in these experiments (Supplemental Figure S1); however, protein levels were not confirmed to ensure equal amounts of active protein were being produced. To better understand the consequence of local activin A overexpression, histopathological analysis was performed on muscles harvested on day 25. This analysis revealed interstitial and perimyocellular macrophage infiltration with necrotic myocytes indicative of an early inflammatory event (Figure 1E). Next, we wanted to identify early gene changes associated with increases of activin A in skeletal muscle. In doing so, we wanted to minimize the interference and difficulty in timing the overexpression with electroporation and adenoviral deliveries. To accomplish this, we examined gene expression changes in muscle after a single intramuscular injection of 5 μg of activin A protein. Predictably, we observed gene changes linked to muscle atrophy, such as f-box protein 32 (Fbxo32) and tripartite motif containing 63 (Trim63) (Figure 2A). However, local introduction of activin A protein surprisingly induced an increase in gene markers related to inflammation, such as tumor necrosis factor (TNF) receptor superfamily member 12A or more commonly known as Tweak receptor (Tnfrsf12a) and TNF α (Tnf), when compared with BSA control (Figure 2B). This finding suggests that locally derived activin A may alter the inflammatory cell milieu at the site of muscle trauma. Having established an increase in muscle-derived activin A expression after CTX injury and identified potential early gene expression changes with local injections of activin A, we set out to explore the consequences of blocking this local increase in activin A in response to CTX injury. To accomplish this, we overexpressed inhibin A, which effectively blocks activin A signaling by forming an inactive heterodimeric complex. Even in the absence of any overt injury, local overexpression using electroporation" @default.
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• W2049951278 title "Inhibition of Activin A Ameliorates Skeletal Muscle Injury and Rescues Contractile Properties by Inducing Efficient Remodeling in Female Mice" @default.
• W2049951278 cites W1970098795 @default.
• W2049951278 cites W1970674526 @default.
• W2049951278 cites W1981158030 @default.
• W2049951278 cites W1982871919 @default.
• W2049951278 cites W1983159021 @default.
• W2049951278 cites W1989214405 @default.
• W2049951278 cites W1994129658 @default.
• W2049951278 cites W1996370046 @default.
• W2049951278 cites W1996399603 @default.
• W2049951278 cites W2000991526 @default.
• W2049951278 cites W2001183029 @default.
• W2049951278 cites W2007757724 @default.
• W2049951278 cites W2008325436 @default.
• W2049951278 cites W2008417845 @default.
• W2049951278 cites W2009557609 @default.
• W2049951278 cites W2010044292 @default.
• W2049951278 cites W2017429680 @default.
• W2049951278 cites W2018988532 @default.
• W2049951278 cites W2019088303 @default.
• W2049951278 cites W2019558909 @default.
• W2049951278 cites W2021984762 @default.
• W2049951278 cites W2026515823 @default.
• W2049951278 cites W2030143181 @default.
• W2049951278 cites W2035635557 @default.
• W2049951278 cites W2044240082 @default.
• W2049951278 cites W2048134135 @default.
• W2049951278 cites W2048569338 @default.
• W2049951278 cites W2053079324 @default.
• W2049951278 cites W2057293159 @default.
• W2049951278 cites W2061495510 @default.
• W2049951278 cites W2061896987 @default.
• W2049951278 cites W2062056760 @default.
• W2049951278 cites W2063881294 @default.
• W2049951278 cites W2065257588 @default.
• W2049951278 cites W2066103558 @default.
• W2049951278 cites W2066197021 @default.
• W2049951278 cites W2066928156 @default.
• W2049951278 cites W2070667194 @default.
• W2049951278 cites W2070881335 @default.
• W2049951278 cites W2076787014 @default.
• W2049951278 cites W2080731799 @default.
• W2049951278 cites W2083409148 @default.
• W2049951278 cites W2083700023 @default.
• W2049951278 cites W2086185423 @default.
• W2049951278 cites W2093932494 @default.
• W2049951278 cites W2094069034 @default.
• W2049951278 cites W2097171062 @default.
• W2049951278 cites W2107128634 @default.
• W2049951278 cites W2108723188 @default.
• W2049951278 cites W2126336330 @default.
• W2049951278 cites W2127247844 @default.
• W2049951278 cites W2144606783 @default.
• W2049951278 cites W2147331787 @default.
• W2049951278 cites W2148402618 @default.
• W2049951278 cites W2149159571 @default.
• W2049951278 cites W2149284281 @default.
• W2049951278 cites W2149993139 @default.
• W2049951278 cites W2151283204 @default.
• W2049951278 cites W2160472630 @default.
• W2049951278 cites W2165658291 @default.
• W2049951278 cites W2169876318 @default.
• W2049951278 cites W4294961496 @default.
• W2049951278 cites W58010252 @default.
• W2049951278 doi "https://doi.org/10.1016/j.ajpath.2013.12.029" @default.
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