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Abstract
Myostatin (GDF-8) was discovered 25 years ago as a new transforming growth factor-β family member that acts as a master regulator of skeletal muscle mass. Myostatin is made by skeletal myofibers, circulates in the blood, and acts back on myofibers to limit growth. Myostatin appears to have all of the salient properties of a chalone, which is a term proposed over a half century ago to describe hypothetical circulating, tissue-specific growth inhibitors that control tissue size. The elucidation of the molecular, cellular, and physiological mechanisms underlying myostatin activity suggests that myostatin functions as a negative feedback regulator of muscle mass and raises the question as to whether this type of chalone mechanism is unique to skeletal muscle or whether it also operates in other tissues.
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Affiliation(s)
- Se-Jin Lee
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, Farmington, Connecticut, USA.,The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut, USA;
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2
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Kappes EC, Kattamuri C, Czepnik M, Yarawsky AE, Brûlé E, Wang Y, Ongaro L, Herr AB, Walton KL, Bernard DJ, Thompson TB. Follistatin Forms a Stable Complex With Inhibin A That Does Not Interfere With Activin A Antagonism. Endocrinology 2023; 164:7010688. [PMID: 36718082 DOI: 10.1210/endocr/bqad017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 01/17/2023] [Accepted: 01/19/2023] [Indexed: 02/01/2023]
Abstract
Inhibins are transforming growth factor-β family heterodimers that suppress follicle-stimulating hormone (FSH) secretion by antagonizing activin class ligands. Inhibins share a common β chain with activin ligands. Follistatin is another activin antagonist, known to bind the common β chain of both activins and inhibins. In this study, we characterized the antagonist-antagonist complex of inhibin A and follistatin to determine if their interaction impacted activin A antagonism. We isolated the inhibin A:follistatin 288 complex, showing that it forms in a 1:1 stoichiometric ratio, different from previously reported homodimeric ligand:follistatin complexes, which bind in a 1:2 ratio. Small angle X-ray scattering coupled with modeling provided a low-resolution structure of inhibin A in complex with follistatin 288. Inhibin binds follistatin via the shared activin β chain, leaving the α chain free and flexible. The inhibin A:follistatin 288 complex was also shown to bind heparin with lower affinity than follistatin 288 alone or in complex with activin A. Characterizing the inhibin A:follistatin 288 complex in an activin-responsive luciferase assay and by surface plasmon resonance indicated that the inhibitor complex readily dissociated upon binding type II receptor activin receptor type IIb, allowing both antagonists to inhibit activin signaling. Additionally, injection of the complex in ovariectomized female mice did not alter inhibin A suppression of FSH. Taken together, this study shows that while follistatin binds to inhibin A with a substochiometric ratio relative to the activin homodimer, the complex can dissociate readily, allowing both proteins to effectively antagonize activin signaling.
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Affiliation(s)
- Emily C Kappes
- Department of Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati, Cincinnati, OH, USA
| | - Chandramohan Kattamuri
- Department of Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati, Cincinnati, OH, USA
| | - Magdalena Czepnik
- Department of Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati, Cincinnati, OH, USA
| | | | - Emilie Brûlé
- Departments of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada
| | - Ying Wang
- Departments of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Luisina Ongaro
- Departments of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Andrew B Herr
- Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Kelly L Walton
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, QLD, Australia
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Daniel J Bernard
- Departments of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada
- Departments of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Thomas B Thompson
- Department of Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati, Cincinnati, OH, USA
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Zhong X, Narasimhan A, Silverman LM, Young AR, Shahda S, Liu S, Wan J, Liu Y, Koniaris LG, Zimmers TA. Sex specificity of pancreatic cancer cachexia phenotypes, mechanisms, and treatment in mice and humans: role of Activin. J Cachexia Sarcopenia Muscle 2022; 13:2146-2161. [PMID: 35510530 PMCID: PMC9397557 DOI: 10.1002/jcsm.12998] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 02/04/2022] [Accepted: 03/16/2022] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Cachexia is frequent, deadly, and untreatable for patients with pancreatic ductal adenocarcinoma (PDAC). The reproductive hormone and cytokine Activin is a mediator of PDAC cachexia, and Activin receptor targeting was clinically tested for cancer cachexia therapy. However, sex-specific manifestations and mechanisms are poorly understood, constraining development of effective treatments. METHODS Cachexia phenotypes, muscle gene/protein expression, and effects of the Activin blocker ACVR2B/Fc were assessed in LSL-KrasG12D/+ , LSL-Trp53R172H/+ , and Pdx-1-Cre (KPC) mice with autochthonic PDAC. Effects of PDAC and sex hormones were modelled by treating C2C12 myotubes with KPC-cell conditioned medium (CM) and estradiol. Muscle gene expression by RNAseq and change in muscle from serial CT scans were measured in patients with PDAC. RESULTS Despite equivalent tumour latency (median 17 weeks) and mortality (24.5 weeks), male KPC mice showed earlier and more severe cachexia than females. In early PDAC, male gastrocnemius, quadriceps, and tibialis anterior muscles were reduced (-21.7%, -18.9%, and -20.8%, respectively, all P < 0.001), with only gastrocnemius reduced in females (-16%, P < 0.01). Sex differences disappeared in late PDAC. Plasma Activin A was similarly elevated between sexes throughout, while oestrogen and testosterone levels suggested a virilizing effect of PDAC in females. Estradiol partially protected myotubes from KPC-CM induced atrophy and promoted expression of the potential Activin inhibitor Fstl1. Early-stage female mice showed greater muscle expression of Activin inhibitors Fst, Fstl1, and Fstl3; this sex difference disappeared by late-stage PDAC. ACVR2B/Fc initiated in early PDAC preserved muscle and fat only in male KPC mice, with increases of 41.2%, 52.6%, 39.3%, and 348.8%, respectively, in gastrocnemius, quadriceps, tibialis, and fat pad weights vs. vehicle controls, without effect on tumour. No protection was observed in females. At protein and RNA levels, pro-atrophy pathways were induced more strongly in early-stage males, with sex differences less evident in late-stage disease. As with mass, ACVR2B/Fc blunted atrophy-associated pathways only in males. In patients with resectable PDAC, muscle expression of Activin inhibitors FSTL1, FSLT3, and WFIKKN2/GASP2 were higher in women than men. Overall, among 124 patients on first-line gemcitabine/nab-paclitaxel for PDAC, only men displayed muscle loss (P < 0.001); average muscle wasting in men was greater (-6.63 ± 10.70% vs. -1.62 ± 12.00% mean ± SD, P = 0.038) and more rapid (-0.0098 ± 0.0742%/day vs. -0.0466 ± 0.1066%/day, P = 0.017) than in women. CONCLUSIONS Pancreatic ductal adenocarcinoma cachexia displays sex-specific phenotypes in mice and humans, with Activin a preferential driver of muscle wasting in males. Sex is a major modulator of cachexia mechanisms. Consideration of sexual dimorphism is essential for discovery and development of effective treatments.
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Affiliation(s)
- Xiaoling Zhong
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
- Richard L. Roudebush Veterans Administration Medical CenterIndianapolisINUSA
| | - Ashok Narasimhan
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
| | | | - Andrew R. Young
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
| | - Safi Shahda
- Department of MedicineIndiana University School of MedicineIndianapolisINUSA
| | - Sheng Liu
- Department of Medical and Molecular GeneticsIndiana University School of MedicineIndianapolisINUSA
- Center for Computational Biology and BioinformaticsIndianapolisINUSA
| | - Jun Wan
- Department of Medical and Molecular GeneticsIndiana University School of MedicineIndianapolisINUSA
- Center for Computational Biology and BioinformaticsIndianapolisINUSA
- Indiana University Melvin and Bren Simon Comprehensive Cancer CenterIndianapolisINUSA
| | - Yunlong Liu
- Department of Medical and Molecular GeneticsIndiana University School of MedicineIndianapolisINUSA
- Center for Computational Biology and BioinformaticsIndianapolisINUSA
- Indiana University Melvin and Bren Simon Comprehensive Cancer CenterIndianapolisINUSA
- Indiana Center for Musculoskeletal HealthIndianapolisINUSA
| | - Leonidas G. Koniaris
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
- Richard L. Roudebush Veterans Administration Medical CenterIndianapolisINUSA
- Indiana University Melvin and Bren Simon Comprehensive Cancer CenterIndianapolisINUSA
- Indiana Center for Musculoskeletal HealthIndianapolisINUSA
| | - Teresa A. Zimmers
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
- Richard L. Roudebush Veterans Administration Medical CenterIndianapolisINUSA
- Center for Computational Biology and BioinformaticsIndianapolisINUSA
- Indiana University Melvin and Bren Simon Comprehensive Cancer CenterIndianapolisINUSA
- Indiana Center for Musculoskeletal HealthIndianapolisINUSA
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Puolakkainen T, Rummukainen P, Pihala-Nieminen V, Ritvos O, Savontaus E, Kiviranta R. Treatment with Soluble Activin Type IIB Receptor Ameliorates Ovariectomy-Induced Bone Loss and Fat Gain in Mice. Calcif Tissue Int 2022; 110:504-517. [PMID: 35024891 PMCID: PMC8927044 DOI: 10.1007/s00223-021-00934-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 11/25/2021] [Indexed: 11/23/2022]
Abstract
INTRODUCTION In postmenopausal osteoporosis, hormonal changes lead to increased bone turnover and metabolic alterations including increased fat mass and insulin resistance. Activin type IIB receptors bind several growth factors of the TGF-β superfamily and have been demonstrated to increase muscle and bone mass. We hypothesized that ActRIIB-Fc treatment could improve bone and muscle mass, inhibit fat accumulation, and restore metabolic alterations in an ovariectomy (OVX) model of postmenopausal osteoporosis. MATERIALS AND METHODS Female C57Bl/6 N mice were subjected to SHAM or OVX procedures and received intraperitoneal injections of either PBS or ActRIIB-Fc (5 mg/kg) once weekly for 7 weeks. Glucose and insulin tolerance tests (GTT and ITT, respectively) were performed at 7 and 8 weeks, respectively. Bone samples were analyzed with micro-computed tomography imaging, histomorphometry, and quantitative RT-PCR. RESULTS Bone mass decreased in OVX PBS mice compared to the SHAM PBS group but ActRIIB-Fc was able to prevent these changes as shown by µCT and histological analyses. This was due to decreased osteoclast numbers and function demonstrated by histomorphometric and qRT-PCR analyses. OVX induced adipocyte hypertrophy that was rescued by ActRIIB-Fc, which also decreased systemic adipose tissue accumulation. OVX itself did not affect glucose levels in GTT but ActRIIB-Fc treatment resulted in impaired glucose clearance in both SHAM and OVX groups. OVX induced mild insulin resistance in ITT but ActRIIB-Fc treatment did not affect this. CONCLUSION Our results reinforce the potency of ActRIIB-Fc as a bone-enhancing agent but also bring new insight into the metabolic effects of ActRIIB-Fc in normal and OVX mice.
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Affiliation(s)
- Tero Puolakkainen
- Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Petri Rummukainen
- Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Vappu Pihala-Nieminen
- Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Olli Ritvos
- Department of Physiology, University of Helsinki, Helsinki, Finland
| | - Eriika Savontaus
- Clinical Pharmacology, Turku University Hospital, Turku, Finland
- Turku Center for Disease Modeling, Institute of Biomedicine, University of Turku, Turku, Finland
| | - Riku Kiviranta
- Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, 20520, Turku, Finland.
- Department of Endocrinology, Division of Medicine, University of Turku and Turku University Hospital, Turku, Finland.
- Turku Center for Disease Modeling, Institute of Biomedicine, University of Turku, Turku, Finland.
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Le VQ, Iacob RE, Zhao B, Su Y, Tian Y, Toohey C, Engen JR, Springer TA. Protection of the Prodomain α1-Helix Correlates with Latency in the Transforming Growth Factor-β Family. J Mol Biol 2022; 434:167439. [PMID: 34990654 PMCID: PMC8981510 DOI: 10.1016/j.jmb.2021.167439] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 11/16/2021] [Accepted: 12/29/2021] [Indexed: 11/18/2022]
Abstract
The 33 members of the transforming growth factor beta (TGF-β) family are fundamentally important for organismal development and homeostasis. Family members are synthesized and secreted as pro-complexes of non-covalently associated prodomains and growth factors (GF). Pro-complexes from a subset of family members are latent and require activation steps to release the GF for signaling. Why some members are latent while others are non-latent is incompletely understood, particularly because of large family diversity. Here, we have examined representative family members in negative stain electron microscopy (nsEM) and hydrogen deuterium exchange (HDX) to identify features that differentiate latent from non-latent members. nsEM showed three overall pro-complex conformations that differed in prodomain arm domain orientation relative to the bound growth factor. Two cross-armed members, TGF-β1 and TGF-β2, were each latent. However, among V-armed members, GDF8 was latent whereas ActA was not. All open-armed members, BMP7, BMP9, and BMP10, were non-latent. Family members exhibited remarkably varying HDX patterns, consistent with large prodomain sequence divergence. A strong correlation emerged between latency and protection of the prodomain α1-helix from exchange. Furthermore, latency and protection from exchange correlated structurally with increased α1-helix buried surface area, hydrogen bonds, and cation-pi bonds. Moreover, a specific pattern of conserved basic and hydrophobic residues in the α1-helix and aromatic residues in the interacting fastener were found only in latent members. Thus, this first comparative survey of TGF-β family members reveals not only diversity in conformation and dynamics but also unique features that distinguish latent members.
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Affiliation(s)
- Viet Q Le
- Program in Cellular and Molecular Medicine, Boston Children's Hospital and Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, United States
| | - Roxana E Iacob
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, United States
| | - Bo Zhao
- Program in Cellular and Molecular Medicine, Boston Children's Hospital and Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, United States; Department of Immunology, Molecular Cancer Research Center, School of Medicine, Sun Yat-sen University, Shenzhen, China
| | - Yang Su
- Program in Cellular and Molecular Medicine, Boston Children's Hospital and Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, United States
| | - Yuan Tian
- Program in Cellular and Molecular Medicine, Boston Children's Hospital and Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, United States
| | - Cameron Toohey
- Program in Cellular and Molecular Medicine, Boston Children's Hospital and Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, United States
| | - John R Engen
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, United States. https://twitter.com/jrengen
| | - Timothy A Springer
- Program in Cellular and Molecular Medicine, Boston Children's Hospital and Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, United States.
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Wang XH, Mitch WE, Price SR. Pathophysiological mechanisms leading to muscle loss in chronic kidney disease. Nat Rev Nephrol 2022; 18:138-152. [PMID: 34750550 DOI: 10.1038/s41581-021-00498-0] [Citation(s) in RCA: 60] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/01/2021] [Indexed: 12/16/2022]
Abstract
Loss of muscle proteins is a deleterious consequence of chronic kidney disease (CKD) that causes a decrease in muscle strength and function, and can lead to a reduction in quality of life and increased risk of morbidity and mortality. The effectiveness of current treatment strategies in preventing or reversing muscle protein losses is limited. The limitations largely stem from the systemic nature of diseases such as CKD, which stimulate skeletal muscle protein degradation pathways while simultaneously activating mechanisms that impair muscle protein synthesis and repair. Stimuli that initiate muscle protein loss include metabolic acidosis, insulin and IGF1 resistance, changes in hormones, cytokines, inflammatory processes and decreased appetite. A growing body of evidence suggests that signalling molecules secreted from muscle can enter the circulation and subsequently interact with recipient organs, including the kidneys, while conversely, pathological events in the kidney can adversely influence protein metabolism in skeletal muscle, demonstrating the existence of crosstalk between kidney and muscle. Together, these signals, whether direct or indirect, induce changes in the levels of regulatory and effector proteins via alterations in mRNAs, microRNAs and chromatin epigenetic responses. Advances in our understanding of the signals and processes that mediate muscle loss in CKD and other muscle wasting conditions will support the future development of therapeutic strategies to reduce muscle loss.
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Affiliation(s)
- Xiaonan H Wang
- Renal Division, Department of Medicine, Emory University, Atlanta, GA, USA
| | - William E Mitch
- Nephrology Division, Department of Medicine, Baylor College of Medicine, Houston, TX, USA
| | - S Russ Price
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, NC, USA. .,Department of Internal Medicine, Brody School of Medicine, East Carolina University, Greenville, NC, USA.
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Ikeno Y, Inomata M, Tsukimura Y, Suzuki Y, Takeuchi H, Harada Y, Kon R, Ikarashi N, Chiba Y, Yamada T, Kamei J, Sakai H. Eicosapentaenoic acid suppresses cisplatin-induced muscle atrophy by attenuating the up-regulated gene expression of ubiquitin. J Nutr Biochem 2022; 103:108953. [PMID: 35121023 DOI: 10.1016/j.jnutbio.2022.108953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 07/15/2021] [Accepted: 01/04/2022] [Indexed: 10/19/2022]
Abstract
Previously it was shown that cisplatin causes muscle atrophy. Under this condition, cisplatin increased the expression of atorogenes, such as muscle ring finger 1 and atrogin-1 (also known as muscle atrophy F-box protein), in mouse skeletal muscle. It was reported recently that ubiquitin (Ub) and ubiquitinated protein levels in skeletal muscle were also up-regulated in cisplatin-induced muscle atrophy, and cisplatin-induced ubiquitinated proteins were degraded by the 26S proteasome pathway. Eicosapentaenoic acid (EPA) is effective against skeletal muscle atrophy in mice. However, it is unclear how EPA suppresses the Ub-proteasome pathway. In this study, the effect of EPA on cisplatin-induced muscle atrophy in mice was examined. Mice were intraperitoneally injected with cisplatin or vehicle control once daily for 4 days. EPA or its vehicle was orally administered 30 min before cisplatin administration. Cisplatin systemic administration induced decrease in muscle mass, myofiber diameter, and increase in Ub genes and ubiquitinated proteins in mouse skeletal muscle were recovered by co-treatment with EPA. However, weight loss and up-regulated atrogenes induced by cisplatin were not changed by co-treatment with EPA in skeletal muscle. In this study, EPA attenuated cisplatin-induced muscle atrophy via down-regulation of up-regulated Ub gene expression. Although further clinical studies are needed, EPA administration can be effective in the development of muscle atrophy in cisplatin-treated patients.
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Affiliation(s)
- Yohei Ikeno
- Department of Biomolecular Pharmacology, School of Pharmacy, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 1428501, Japan
| | - Maya Inomata
- Department of Biomolecular Pharmacology, School of Pharmacy, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 1428501, Japan
| | - Yuka Tsukimura
- Department of Biomolecular Pharmacology, School of Pharmacy, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 1428501, Japan
| | - Yuta Suzuki
- Department of Biomolecular Pharmacology, School of Pharmacy, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 1428501, Japan
| | - Hiroto Takeuchi
- Department of Biomolecular Pharmacology, School of Pharmacy, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 1428501, Japan
| | - Yui Harada
- Department of Biomolecular Pharmacology, School of Pharmacy, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 1428501, Japan
| | - Risako Kon
- Department of Biomolecular Pharmacology, School of Pharmacy, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 1428501, Japan
| | - Nobutomo Ikarashi
- Department of Biomolecular Pharmacology, School of Pharmacy, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 1428501, Japan
| | - Yoshihiko Chiba
- Laboratory of Molecular Biology and Physiology, School of Pharmacy, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 1428501, Japan
| | - Takeshi Yamada
- Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery, Nippon Medical School, Tokyo, Japan
| | - Junzo Kamei
- Department of Biomolecular Pharmacology, School of Pharmacy, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 1428501, Japan
| | - Hiroyasu Sakai
- Department of Biomolecular Pharmacology, School of Pharmacy, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 1428501, Japan.
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The role of pro-domains in human growth factors and cytokines. Biochem Soc Trans 2021; 49:1963-1973. [PMID: 34495310 PMCID: PMC8589418 DOI: 10.1042/bst20200663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/17/2021] [Accepted: 08/19/2021] [Indexed: 11/30/2022]
Abstract
Many growth factors and cytokines are produced as larger precursors, containing pro-domains, that require proteolytic processing to release the bioactive ligand. These pro-domains can be significantly larger than the mature domains and can play an active role in the regulation of the ligands. Mining the UniProt database, we identified almost one hundred human growth factors and cytokines with pro-domains. These are spread across several unrelated protein families and vary in both their size and composition. The precise role of each pro-domain varies significantly between the protein families. Typically they are critical for controlling bioactivity and protein localisation, and they facilitate diverse mechanisms of activation. Significant gaps in our understanding remain for pro-domain function — particularly their fate once the bioactive ligand has been released. Here we provide an overview of pro-domain roles in human growth factors and cytokines, their processing, regulation and activation, localisation as well as therapeutic potential.
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Potential of Activin B as a Clinical Biomarker in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). Biomolecules 2021; 11:biom11081189. [PMID: 34439855 PMCID: PMC8394088 DOI: 10.3390/biom11081189] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 08/09/2021] [Accepted: 08/10/2021] [Indexed: 12/13/2022] Open
Abstract
Reliable serum biomarkers are of immense need for diagnostic purposes of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)-a disabling and complex disease for which diagnosis is mainly based on clinical symptoms. The aim of this study was to evaluate a possible diagnostic potential of activin B by directly comparing 134 cases of ME/CFS with 54 healthy controls. Analyses of human activin B level in plasma samples were performed using a validated human activin B ELISA assay. The results of the study show that activin B levels did not differ statistically significantly between ME/CFS patients and healthy controls (p = 0.6511). No gender or age-related differences in activin B levels were observed in the ME/CFS group and healthy controls. The level of activin B tended to decrease with increasing visual analogue scale score (r = -0.2004; p = 0.5085) nevertheless the results obtained so far does not support the clinical utility of activin B as a biomarker for ME/CFS.
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10
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Characterization of tolloid-mediated cleavage of the GDF8 procomplex. Biochem J 2021; 478:1733-1747. [PMID: 33876824 DOI: 10.1042/bcj20210054] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 04/15/2021] [Accepted: 04/19/2021] [Indexed: 12/14/2022]
Abstract
Growth differentiation factor 8 (GDF8), a.k.a. myostatin, is a member of the larger TGFβ superfamily of signaling ligands. GDF8 has been well characterized as a negative regulator of muscle mass. After synthesis, GDF8 is held latent by a noncovalent complex between the N-terminal prodomain and the signaling ligand. Activation of latent GDF8 requires proteolytic cleavage of the prodomain at residue D99 by a member of the tolloid family of metalloproteases. While tolloid proteases cleave multiple substrates, they lack a conserved consensus sequence. Here, we investigate the tolloid cleavage site of the GDF8 prodomain to determine what residues contribute to tolloid recognition and subsequent proteolysis. Using sequential alanine mutations, we identified several residues adjacent to the scissile bond, including Y94, that when mutated, abolish tolloid-mediated activation of latent GDF8. Using the astacin domain of Tll1 (Tolloid Like 1) we determined that prodomain mutants were more resistant to proteolysis. Purified latent complexes harboring the prodomain mutations, D92A and Y94A, impeded activation by tolloid but could be fully activated under acidic conditions. Finally, we show that co-expression of GDF8 WT with prodomain mutants that were tolloid resistant, suppressed GDF8 activity. Taken together our data demonstrate that residues towards the N-terminus of the scissile bond are important for tolloid-mediated activation of GDF8 and that the tolloid-resistant version of the GDF8 prodomain can function dominant negative to WT GDF8.
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11
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Targeting the Activin Receptor Signaling to Counteract the Multi-Systemic Complications of Cancer and Its Treatments. Cells 2021; 10:cells10030516. [PMID: 33671024 PMCID: PMC7997313 DOI: 10.3390/cells10030516] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 02/23/2021] [Accepted: 02/24/2021] [Indexed: 02/07/2023] Open
Abstract
Muscle wasting, i.e., cachexia, frequently occurs in cancer and associates with poor prognosis and increased morbidity and mortality. Anticancer treatments have also been shown to contribute to sustainment or exacerbation of cachexia, thus affecting quality of life and overall survival in cancer patients. Pre-clinical studies have shown that blocking activin receptor type 2 (ACVR2) or its ligands and their downstream signaling can preserve muscle mass in rodents bearing experimental cancers, as well as in chemotherapy-treated animals. In tumor-bearing mice, the prevention of skeletal and respiratory muscle wasting was also associated with improved survival. However, the definitive proof that improved survival directly results from muscle preservation following blockade of ACVR2 signaling is still lacking, especially considering that concurrent beneficial effects in organs other than skeletal muscle have also been described in the presence of cancer or following chemotherapy treatments paired with counteraction of ACVR2 signaling. Hence, here, we aim to provide an up-to-date literature review on the multifaceted anti-cachectic effects of ACVR2 blockade in preclinical models of cancer, as well as in combination with anticancer treatments.
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12
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Kim MJ, O'Connor MB. Drosophila Activin signaling promotes muscle growth through InR/TORC1-dependent and -independent processes. Development 2021; 148:dev190868. [PMID: 33234715 PMCID: PMC7823159 DOI: 10.1242/dev.190868] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Accepted: 11/16/2020] [Indexed: 12/25/2022]
Abstract
The Myostatin/Activin branch of the TGF-β superfamily acts as a negative regulator of vertebrate skeletal muscle size, in part, through downregulation of insulin/insulin-like growth factor 1 (IGF-1) signaling. Surprisingly, recent studies in Drosophila indicate that motoneuron-derived Activin signaling acts as a positive regulator of muscle size. Here we demonstrate that Drosophila Activin signaling promotes the growth of muscle cells along all three axes: width, thickness and length. Activin signaling positively regulates the insulin receptor (InR)/TORC1 pathway and the level of Myosin heavy chain (Mhc), an essential sarcomeric protein, via increased Pdk1 and Akt1 expression. Enhancing InR/TORC1 signaling in the muscle of Activin pathway mutants restores Mhc levels close to those of the wild type, but only increases muscle width. In contrast, hyperactivation of the Activin pathway in muscles increases overall larval body and muscle fiber length, even when Mhc levels are lowered by suppression of TORC1. Together, these results indicate that the Drosophila Activin pathway regulates larval muscle geometry and body size via promoting InR/TORC1-dependent Mhc production and the differential assembly of sarcomeric components into either pre-existing or new sarcomeric units depending on the balance of InR/TORC1 and Activin signals.
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Affiliation(s)
- Myung-Jun Kim
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Michael B O'Connor
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
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13
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Khanal P, He L, Herbert AJ, Stebbings GK, Onambele-Pearson GL, Degens H, Morse CI, Thomis M, Williams AG. The Association of Multiple Gene Variants with Ageing Skeletal Muscle Phenotypes in Elderly Women. Genes (Basel) 2020; 11:genes11121459. [PMID: 33291384 PMCID: PMC7762041 DOI: 10.3390/genes11121459] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 11/24/2020] [Accepted: 12/03/2020] [Indexed: 12/20/2022] Open
Abstract
There is a scarcity of studies that have investigated the role of multiple single nucleotide polymorphisms (SNPs) on a range of muscle phenotypes in an elderly population. The present study investigated the possible association of 24 SNPs with skeletal muscle phenotypes in 307 elderly Caucasian women (aged 60–91 years, 66.3 ± 11.3 kg). Skeletal muscle phenotypes included biceps brachii thickness, vastus lateralis cross-sectional areas, maximal hand grip strength, isometric knee extension and elbow flexion torque. Genotyping for 24 SNPs, chosen on their skeletal muscle structural or functional links, was conducted on DNA extracted from blood or saliva. Of the 24 SNPs, 10 were associated with at least one skeletal muscle phenotype. HIF1A rs11549465 was associated with three skeletal muscle phenotypes and PTK2 rs7460 and ACVR1B rs10783485 were each associated with two phenotypes. PTK2 rs7843014, COL1A1 rs1800012, CNTF rs1800169, NOS3 rs1799983, MSTN rs1805086, TRHR rs7832552 and FTO rs9939609 were each associated with one. Elderly women possessing favourable genotypes were 3.6–13.2% stronger and had 4.6–14.7% larger muscle than those with less favourable genotypes. These associations, together with future work involving a broader range of SNPs, may help identify individuals at particular risk of an age-associated loss of independence.
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Affiliation(s)
- Praval Khanal
- Musculoskeletal Science and Sports Medicine Research Centre, Department of Sport and Exercise Sciences, Manchester Metropolitan University, Manchester M15 6BH, UK; (L.H.); (G.K.S.); (G.L.O.-P.); (C.I.M.); (A.G.W.)
- Department of Movement Sciences, Physical Activity, Sports & Health Research Group, KU Leuven, 3001 Leuven, Belgium;
- Correspondence: ; Tel.: +977-9841528705
| | - Lingxiao He
- Musculoskeletal Science and Sports Medicine Research Centre, Department of Sport and Exercise Sciences, Manchester Metropolitan University, Manchester M15 6BH, UK; (L.H.); (G.K.S.); (G.L.O.-P.); (C.I.M.); (A.G.W.)
- Department of Movement Sciences, Physical Activity, Sports & Health Research Group, KU Leuven, 3001 Leuven, Belgium;
| | - Adam J. Herbert
- Department of Sport and Exercise, Birmingham City University, Birmingham B5 5JU, UK;
| | - Georgina K. Stebbings
- Musculoskeletal Science and Sports Medicine Research Centre, Department of Sport and Exercise Sciences, Manchester Metropolitan University, Manchester M15 6BH, UK; (L.H.); (G.K.S.); (G.L.O.-P.); (C.I.M.); (A.G.W.)
| | - Gladys L. Onambele-Pearson
- Musculoskeletal Science and Sports Medicine Research Centre, Department of Sport and Exercise Sciences, Manchester Metropolitan University, Manchester M15 6BH, UK; (L.H.); (G.K.S.); (G.L.O.-P.); (C.I.M.); (A.G.W.)
| | - Hans Degens
- Department of Life Sciences, Manchester Metropolitan University, Manchester M15 6BH, UK;
- Institute of Sport Science and Innovations, Lithuanian Sports University, LT-44221 Kaunsas, Lithuania
- Pharmacy of Targu Mures, University of Medicine, 540142 Targu Mures, Romania
| | - Christopher I. Morse
- Musculoskeletal Science and Sports Medicine Research Centre, Department of Sport and Exercise Sciences, Manchester Metropolitan University, Manchester M15 6BH, UK; (L.H.); (G.K.S.); (G.L.O.-P.); (C.I.M.); (A.G.W.)
| | - Martine Thomis
- Department of Movement Sciences, Physical Activity, Sports & Health Research Group, KU Leuven, 3001 Leuven, Belgium;
| | - Alun G. Williams
- Musculoskeletal Science and Sports Medicine Research Centre, Department of Sport and Exercise Sciences, Manchester Metropolitan University, Manchester M15 6BH, UK; (L.H.); (G.K.S.); (G.L.O.-P.); (C.I.M.); (A.G.W.)
- Institute of Sport, Exercise and Health, University College London, London W1T 7HA, UK
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14
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Hagg A, Kharoud S, Goodchild G, Goodman CA, Chen JL, Thomson RE, Qian H, Gregorevic P, Harrison CA, Walton KL. TMEPAI/PMEPA1 Is a Positive Regulator of Skeletal Muscle Mass. Front Physiol 2020; 11:560225. [PMID: 33250771 PMCID: PMC7672205 DOI: 10.3389/fphys.2020.560225] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 10/12/2020] [Indexed: 12/20/2022] Open
Abstract
Inhibition of myostatin- and activin-mediated SMAD2/3 signaling using ligand traps, such as soluble receptors, ligand-targeting propeptides and antibodies, or follistatin can increase skeletal muscle mass in healthy mice and ameliorate wasting in models of cancer cachexia and muscular dystrophy. However, clinical translation of these extracellular approaches targeting myostatin and activin has been hindered by the challenges of achieving efficacy without potential effects in other tissues. Toward the goal of developing tissue-specific myostatin/activin interventions, we explored the ability of transmembrane prostate androgen-induced (TMEPAI), an inhibitor of transforming growth factor-β (TGF-β1)-mediated SMAD2/3 signaling, to promote growth, and counter atrophy, in skeletal muscle. In this study, we show that TMEPAI can block activin A, activin B, myostatin and GDF-11 activity in vitro. To determine the physiological significance of TMEPAI, we employed Adeno-associated viral vector (AAV) delivery of a TMEPAI expression cassette to the muscles of healthy mice, which increased mass by as much as 30%, due to hypertrophy of muscle fibers. To demonstrate that TMEPAI mediates its effects via inhibition of the SMAD2/3 pathway, tibialis anterior (TA) muscles of mice were co-injected with AAV vectors expressing activin A and TMEPAI. In this setting, TMEPAI blocked skeletal muscle wasting driven by activin-induced phosphorylation of SMAD3. In a model of cancer cachexia associated with elevated circulating activin A, delivery of AAV:TMEPAI into TA muscles of mice bearing C26 colon tumors ameliorated the muscle atrophy normally associated with cancer progression. Collectively, the findings indicate that muscle-directed TMEPAI gene delivery can inactivate the activin/myostatin-SMAD3 pathway to positively regulate muscle mass in healthy settings and models of disease.
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Affiliation(s)
- Adam Hagg
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.,Centre for Muscle Research, Department of Physiology, The University of Melbourne, Melbourne, VIC, Australia.,Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Swati Kharoud
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.,Faculty of Science, Engineering and Technology, Swinburne University of Technology, Melbourne, VIC, Australia
| | - Georgia Goodchild
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Craig A Goodman
- Centre for Muscle Research, Department of Physiology, The University of Melbourne, Melbourne, VIC, Australia.,Australian Institute for Musculoskeletal Science, Sunshine Hospital, The University of Melbourne, St Albans, VIC, Australia
| | - Justin L Chen
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.,Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Rachel E Thomson
- Centre for Muscle Research, Department of Physiology, The University of Melbourne, Melbourne, VIC, Australia.,Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Hongwei Qian
- Centre for Muscle Research, Department of Physiology, The University of Melbourne, Melbourne, VIC, Australia.,Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Paul Gregorevic
- Centre for Muscle Research, Department of Physiology, The University of Melbourne, Melbourne, VIC, Australia.,Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia.,Department of Neurology, The University of Washington School of Medicine, Seattle, WA, United States
| | - Craig A Harrison
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.,Hudson Institute of Medical Research, Clayton, VIC, Australia
| | - Kelly L Walton
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.,Hudson Institute of Medical Research, Clayton, VIC, Australia
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15
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Wang J, Zhang K, Hou X, Yue W, Yang H, Chen X, Wang J, Wang C. Molecular characteristic of activin receptor IIB and its functions in growth and nutrient regulation in Eriocheir sinensis. PeerJ 2020; 8:e9673. [PMID: 32953259 PMCID: PMC7473049 DOI: 10.7717/peerj.9673] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 07/16/2020] [Indexed: 01/08/2023] Open
Abstract
Activin receptor IIB (ActRIIB) is a serine/threonine-kinase receptor binding with transforming growth factor-β (TGF-β) superfamily ligands to participate in the regulation of muscle mass in vertebrates. However, its structure and function in crustaceans remain unknown. In this study, the ActRIIB gene in Eriocheir sinensis (Es-ActRIIB) was cloned and obtained with a 1,683 bp open reading frame, which contains the characteristic domains of TGF-β type II receptor superfamily, encoding 560 amino acids. The mRNA expression of Es-ActRIIB was the highest in hepatopancreas and the lowest in muscle at each molting stage. After injection of Es-ActRIIB double-stranded RNA during one molting cycle, the RNA interference (RNAi) group showed higher weight gain rate, higher specific growth rate, and lower hepatopancreas index compared with the control group. Meanwhile, the RNAi group displayed a significantly increased content of hydrolytic amino acid in both hepatopancreas and muscle. The RNAi group also displayed slightly higher contents of saturated fatty acid and monounsaturated fatty acid but significantly decreased levels of polyunsaturated fatty acid compared with the control group. After RNAi on Es-ActRIIB, the mRNA expressions of five ActRIIB signaling pathway genes showed that ActRI and forkhead box O (FoxO) were downregulated in hepatopancreas and muscle, but no significant expression differences were found in small mother against decapentaplegic (SMAD) 3, SMAD4 and mammalian target of rapamycin. The mRNA expression s of three lipid metabolism-related genes (carnitine palmitoyltransferase 1β (CPT1β), fatty acid synthase, and fatty acid elongation) were significantly downregulated in both hepatopancreas and muscle with the exception of CPT1β in muscles. These results indicate that ActRIIB is a functionally conservative negative regulator in growth mass, and protein and lipid metabolism could be affected by inhibiting ActRIIB signaling in crustacean.
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Affiliation(s)
- Jingan Wang
- Key Laboratory of Freshwater Fisheries Germplasm Resources, Ministry of Agriculture and Rural Affairs, National Demonstration Center for Experimental Fisheries Science Education / Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai, China
| | - Kaijun Zhang
- Key Laboratory of Freshwater Fisheries Germplasm Resources, Ministry of Agriculture and Rural Affairs, National Demonstration Center for Experimental Fisheries Science Education / Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai, China
| | - Xin Hou
- Key Laboratory of Freshwater Fisheries Germplasm Resources, Ministry of Agriculture and Rural Affairs, National Demonstration Center for Experimental Fisheries Science Education / Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai, China
| | - Wucheng Yue
- Key Laboratory of Freshwater Fisheries Germplasm Resources, Ministry of Agriculture and Rural Affairs, National Demonstration Center for Experimental Fisheries Science Education / Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai, China
| | - He Yang
- Key Laboratory of Freshwater Fisheries Germplasm Resources, Ministry of Agriculture and Rural Affairs, National Demonstration Center for Experimental Fisheries Science Education / Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai, China
| | - Xiaowen Chen
- Key Laboratory of Freshwater Fisheries Germplasm Resources, Ministry of Agriculture and Rural Affairs, National Demonstration Center for Experimental Fisheries Science Education / Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai, China
| | - Jun Wang
- Key Laboratory of Freshwater Fisheries Germplasm Resources, Ministry of Agriculture and Rural Affairs, National Demonstration Center for Experimental Fisheries Science Education / Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai, China
| | - Chenghui Wang
- Key Laboratory of Freshwater Fisheries Germplasm Resources, Ministry of Agriculture and Rural Affairs, National Demonstration Center for Experimental Fisheries Science Education / Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai, China
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16
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von Palffy S, Landberg N, Sandén C, Zacharaki D, Shah M, Nakamichi N, Hansen N, Askmyr M, Lilljebjörn H, Rissler M, Karlsson C, Scheding S, Richter J, Eaves CJ, Bhatia R, Järås M, Fioretos T. A high-content cytokine screen identifies myostatin propeptide as a positive regulator of primitive chronic myeloid leukemia cells. Haematologica 2020; 105:2095-2104. [PMID: 31582541 PMCID: PMC7395258 DOI: 10.3324/haematol.2019.220434] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 09/26/2019] [Indexed: 12/30/2022] Open
Abstract
Aberrantly expressed cytokines in the bone marrow (BM) niche are increasingly recognized as critical mediators of survival and expansion of leukemic stem cells. To identify regulators of primitive chronic myeloid leukemia (CML) cells, we performed a high-content cytokine screen using primary CD34+ CD38low chronic phase CML cells. Out of the 313 unique human cytokines evaluated, 11 were found to expand cell numbers ≥2-fold in a 7-day culture. Focusing on novel positive regulators of primitive CML cells, the myostatin antagonist myostatin propeptide gave the largest increase in cell expansion and was chosen for further studies. Herein, we demonstrate that myostatin propeptide expands primitive CML and normal BM cells, as shown by increased colony-forming capacity. For primary CML samples, retention of CD34-expression was also seen after culture. Furthermore, we show expression of MSTN by CML mesenchymal stromal cells, and that myostatin propeptide has a direct and instant effect on CML cells, independent of myostatin, by demonstrating binding of myostatin propeptide to the cell surface and increased phosphorylation of STAT5 and SMAD2/3. In summary, we identify myostatin propeptide as a novel positive regulator of primitive CML cells and corresponding normal hematopoietic cells.
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Affiliation(s)
- Sofia von Palffy
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, Lund, Sweden
| | - Niklas Landberg
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, Lund, Sweden
| | - Carl Sandén
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, Lund, Sweden
| | - Dimitra Zacharaki
- Division of Molecular Hematology, Lund Stem Cell Center, Lund University, Lund, Sweden
| | - Mansi Shah
- Division of Hematology, Oncology and Bone Marrow Transplantation, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Naoto Nakamichi
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Nils Hansen
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, Lund, Sweden
| | - Maria Askmyr
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, Lund, Sweden
| | - Henrik Lilljebjörn
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, Lund, Sweden
| | - Marianne Rissler
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, Lund, Sweden
| | - Christine Karlsson
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, Lund, Sweden
| | - Stefan Scheding
- Division of Molecular Hematology, Lund Stem Cell Center, Lund University, Lund, Sweden
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Johan Richter
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Connie J Eaves
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Ravi Bhatia
- Division of Hematology, Oncology and Bone Marrow Transplantation, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Marcus Järås
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, Lund, Sweden
| | - Thoas Fioretos
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, Lund, Sweden
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17
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Nguyen HQ, Iskenderian A, Ehmann D, Jasper P, Zhang Z, Rong H, Welty D, Narayanan R. Leveraging Quantitative Systems Pharmacology Approach into Development of Human Recombinant Follistatin Fusion Protein for Duchenne Muscular Dystrophy. CPT-PHARMACOMETRICS & SYSTEMS PHARMACOLOGY 2020; 9:342-352. [PMID: 32419339 PMCID: PMC7306616 DOI: 10.1002/psp4.12518] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 04/13/2020] [Indexed: 12/12/2022]
Abstract
Quantitative understanding about the dynamics of drug-target interactions in biological systems is essential, especially in rare disease programs with small patient populations. Follistatin, by antagonism of myostatin and activin, which are negative regulators of skeletal muscle and inflammatory response, is a promising therapeutic target for Duchenne Muscular Dystrophy. In this study, we constructed a quantitative systems pharmacology model for FS-EEE-Fc, a follistatin recombinant protein to investigate its efficacy from dual target binding, and, subsequently, to project its human efficacious dose. Based on model simulations, with an assumed efficacy threshold of 7-10% muscle volume increase, 3-5 mg/kg weekly dosing of FS-EEE-Fc is predicted to achieve meaningful clinical outcome. In conclusion, the study demonstrated an application of mechanism driven approach at early stage of a rare disease drug development to support lead compound optimization, enable human dose, pharmacokinetics, and efficacy predictions.
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Affiliation(s)
- Hoa Q Nguyen
- Shire HGT, Inc. (a Takeda company), Lexington, Massachusetts, USA
| | | | - David Ehmann
- Shire HGT, Inc. (a Takeda company), Lexington, Massachusetts, USA
| | - Paul Jasper
- RES Group, Inc., Needham, Massachusetts, USA
| | | | - Haojing Rong
- Kymera Therapeutics, Cambridge, Massachusetts, USA
| | - Devin Welty
- Nuventra Pharma Sciences, Research Triangle Park, North Carolina, USA
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18
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Cisplatin-Induced Skeletal Muscle Dysfunction: Mechanisms and Counteracting Therapeutic Strategies. Int J Mol Sci 2020; 21:ijms21041242. [PMID: 32069876 PMCID: PMC7072891 DOI: 10.3390/ijms21041242] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 02/08/2020] [Accepted: 02/09/2020] [Indexed: 12/17/2022] Open
Abstract
Among the severe side effects induced by cisplatin chemotherapy, muscle wasting is the most relevant one. This effect is a major cause for a clinical decline of cancer patients, since it is a negative predictor of treatment outcome and associated to increased mortality. However, despite its toxicity even at low doses, cisplatin remains the first-line therapy for several types of solid tumors. Thus, effective pharmacological treatments counteracting or minimizing cisplatin-induced muscle wasting are urgently needed. The dissection of the molecular pathways responsible for cisplatin-induced muscle dysfunction gives the possibility to identify novel promising therapeutic targets. In this context, the use of animal model of cisplatin-induced cachexia is very useful. Here, we report an update of the most relevant researches on the mechanisms underlying cisplatin-induced muscle wasting and on the most promising potential therapeutic options to preserve muscle mass and function.
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19
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Zhong X, Pons M, Poirier C, Jiang Y, Liu J, Sandusky GE, Shahda S, Nakeeb A, Schmidt CM, House MG, Ceppa EP, Zyromski NJ, Liu Y, Jiang G, Couch ME, Koniaris LG, Zimmers TA. The systemic activin response to pancreatic cancer: implications for effective cancer cachexia therapy. J Cachexia Sarcopenia Muscle 2019; 10:1083-1101. [PMID: 31286691 PMCID: PMC6818463 DOI: 10.1002/jcsm.12461] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 04/19/2019] [Accepted: 05/14/2019] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Pancreatic ductal adenocarcinoma (PDAC) is a particularly lethal malignancy partly due to frequent, severe cachexia. Serum activin correlates with cachexia and mortality, while exogenous activin causes cachexia in mice. METHODS Isoform-specific activin expression and activities were queried in human and murine tumours and PDAC models. Activin inhibition was by administration of soluble activin type IIB receptor (ACVR2B/Fc) and by use of skeletal muscle specific dominant negative ACVR2B expressing transgenic mice. Feed-forward activin expression and muscle wasting activity were tested in vivo and in vitro on myotubes. RESULTS Murine PDAC tumour-derived cell lines expressed activin-βA but not activin-βB. Cachexia severity increased with activin expression. Orthotopic PDAC tumours expressed activins, induced activin expression by distant organs, and produced elevated serum activins. Soluble factors from PDAC elicited activin because conditioned medium from PDAC cells induced activin expression, activation of p38 MAP kinase, and atrophy of myotubes. The activin trap ACVR2B/Fc reduced tumour growth, prevented weight loss and muscle wasting, and prolonged survival in mice with orthotopic tumours made from activin-low cell lines. ACVR2B/Fc also reduced cachexia in mice with activin-high tumours. Activin inhibition did not affect activin expression in organs. Hypermuscular mice expressing dominant negative ACVR2B in muscle were protected for weight loss but not mortality when implanted with orthotopic tumours. Human tumours displayed staining for activin, and expression of the gene encoding activin-βA (INHBA) correlated with mortality in patients with PDAC, while INHBB and other related factors did not. CONCLUSIONS Pancreatic adenocarcinoma tumours are a source of activin and elicit a systemic activin response in hosts. Human tumours express activins and related factors, while mortality correlates with tumour activin A expression. PDAC tumours also choreograph a systemic activin response that induces organ-specific and gene-specific expression of activin isoforms and muscle wasting. Systemic blockade of activin signalling could preserve muscle and prolong survival, while skeletal muscle-specific activin blockade was only protective for weight loss. Our findings suggest the potential and need for gene-specific and organ-specific interventions. Finally, development of more effective cancer cachexia therapy might require identifying agents that effectively and/or selectively inhibit autocrine vs. paracrine activin signalling.
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Affiliation(s)
- Xiaoling Zhong
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
- IUPUI Center for Cachexia Innovation, Research and TherapyIndianapolisINUSA
| | - Marianne Pons
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
| | - Christophe Poirier
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
| | - Yanlin Jiang
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
| | - Jianguo Liu
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
| | - George E. Sandusky
- Department of Pathology and Laboratory MedicineIndiana University School of MedicineIndianapolisINUSA
- IU Simon Cancer CenterIndianapolisINUSA
| | - Safi Shahda
- IU Simon Cancer CenterIndianapolisINUSA
- Department of MedicineIndiana University School of MedicineIndianapolisINUSA
| | - Attila Nakeeb
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
- IU Simon Cancer CenterIndianapolisINUSA
| | - C. Max Schmidt
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
- IU Simon Cancer CenterIndianapolisINUSA
| | - Michael G. House
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
- IU Simon Cancer CenterIndianapolisINUSA
| | - Eugene P. Ceppa
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
- IU Simon Cancer CenterIndianapolisINUSA
| | - Nicholas J. Zyromski
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
- IU Simon Cancer CenterIndianapolisINUSA
| | - Yunlong Liu
- IUPUI Center for Cachexia Innovation, Research and TherapyIndianapolisINUSA
- IU Simon Cancer CenterIndianapolisINUSA
- Department of Medical and Molecular GeneticsIndiana University School of MedicineIndianapolisINUSA
- Center for Computational Biology and BioinformaticsIndiana University School of MedicineIndianapolisINUSA
- Indiana Center for Musculoskeletal HealthIndiana University School of MedicineIndianapolisINUSA
| | - Guanglong Jiang
- Department of Medical and Molecular GeneticsIndiana University School of MedicineIndianapolisINUSA
| | - Marion E. Couch
- IU Simon Cancer CenterIndianapolisINUSA
- Indiana Center for Musculoskeletal HealthIndiana University School of MedicineIndianapolisINUSA
- Department of Otolaryngology—Head & Neck SurgeryIndiana University School of MedicineIndianapolisINUSA
| | - Leonidas G. Koniaris
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
- IUPUI Center for Cachexia Innovation, Research and TherapyIndianapolisINUSA
- IU Simon Cancer CenterIndianapolisINUSA
- Indiana Center for Musculoskeletal HealthIndiana University School of MedicineIndianapolisINUSA
| | - Teresa A. Zimmers
- Department of SurgeryIndiana University School of MedicineIndianapolisINUSA
- IUPUI Center for Cachexia Innovation, Research and TherapyIndianapolisINUSA
- IU Simon Cancer CenterIndianapolisINUSA
- Indiana Center for Musculoskeletal HealthIndiana University School of MedicineIndianapolisINUSA
- Department of Otolaryngology—Head & Neck SurgeryIndiana University School of MedicineIndianapolisINUSA
- Department of Anatomy, Cell Biology & PhysiologyIndiana University School of MedicineIndianapolisINUSA
- Department of Biochemistry and Molecular BiologyIndiana University School of MedicineIndianapolisINUSA
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20
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Walton KL, Chen JL, Arnold Q, Kelly E, La M, Lu L, Lovrecz G, Hagg A, Colgan TD, Qian H, Gregorevic P, Harrison CA. Activin A-Induced Cachectic Wasting Is Attenuated by Systemic Delivery of Its Cognate Propeptide in Male Mice. Endocrinology 2019; 160:2417-2426. [PMID: 31322699 DOI: 10.1210/en.2019-00257] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 07/12/2019] [Indexed: 12/12/2022]
Abstract
In cancer, elevated activin levels promote cachectic wasting of muscle, irrespective of tumor progression. In excess, activins A and B use the myostatin signaling pathway in muscle, triggering a decrease in protein synthesis and an increase in protein degradation, which ultimately leads to atrophy. Recently, we demonstrated that local delivery of engineered activin and myostatin propeptides (natural inhibitors of these growth factors) could induce profound muscle hypertrophy in healthy mice. Additionally, the expression of these propeptides effectively attenuated localized muscle wasting in models of dystrophy and cancer cachexia. In this study, we examined whether a systemically administered recombinant propeptide could reverse activin A-induced cachectic wasting in mice. Chinese hamster ovary cells stably expressing activin A were transplanted into the quadriceps of nude mice and caused an 85-fold increase in circulating activin A levels within 12 days. Elevated activin A induced a rapid reduction in body mass (-16%) and lean mass (-10%). In agreement with previous findings, we demonstrated that adeno-associated virus-mediated delivery of activin propeptide to the tibialis anterior muscle blocked activin-induced wasting. In addition, despite massively elevated levels of activin A in this model, systemic delivery of the propeptide significantly reduced activin-induced changes in lean and body mass. Specifically, recombinant propeptide reversed activin-induced wasting of skeletal muscle, heart, liver, and kidneys. This is the first study to demonstrate that systemic administration of recombinant propeptide therapy effectively attenuates tumor-derived activin A insult in multiple tissues.
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Affiliation(s)
- Kelly L Walton
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Victoria, Australia
- Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Justin L Chen
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Victoria, Australia
- Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Quinn Arnold
- Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Victoria, Australia
| | - Emily Kelly
- Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Mylinh La
- National Collaborative Research Infrastructure Strategy Facility, Commonwealth Scientific and Industrial Research Organisation BioMedical Manufacturing Program, Clayton, Victoria, Australia
| | - Louis Lu
- National Collaborative Research Infrastructure Strategy Facility, Commonwealth Scientific and Industrial Research Organisation BioMedical Manufacturing Program, Clayton, Victoria, Australia
| | - George Lovrecz
- National Collaborative Research Infrastructure Strategy Facility, Commonwealth Scientific and Industrial Research Organisation BioMedical Manufacturing Program, Clayton, Victoria, Australia
| | - Adam Hagg
- Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Department of Physiology, Centre for Muscle Research, The University of Melbourne, Melbourne, Victoria, Australia
| | - Timothy D Colgan
- Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Hongwei Qian
- Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Department of Physiology, Centre for Muscle Research, The University of Melbourne, Melbourne, Victoria, Australia
| | - Paul Gregorevic
- Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Victoria, Australia
- Department of Physiology, Centre for Muscle Research, The University of Melbourne, Melbourne, Victoria, Australia
- Department of Neurology, University of Washington School of Medicine, Seattle, Washington
| | - Craig A Harrison
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Victoria, Australia
- Hudson Institute of Medical Research, Clayton, Victoria, Australia
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Seachrist DD, Keri RA. The Activin Social Network: Activin, Inhibin, and Follistatin in Breast Development and Cancer. Endocrinology 2019; 160:1097-1110. [PMID: 30874767 PMCID: PMC6475112 DOI: 10.1210/en.2019-00015] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 03/08/2019] [Indexed: 12/13/2022]
Abstract
Activins and inhibins are closely related protein heterodimers with a similar tissue distribution; however, these two complexes have opposing functions in development and disease. Both are secreted cytokine hormones, with activin the primary inducer of downstream signaling cascades and inhibin acting as a rheostat that exquisitely governs activin function. Adding to the complexity of activin signaling, follistatin, a highly glycosylated monomeric protein, binds activin with high affinity and restrains downstream pathway activation but through a mechanism distinct from that of inhibin. These three proteins were first identified as key ovarian hormones in the pituitary-gonadal axis that direct the synthesis and secretion of FSH from the pituitary, hence controlling folliculogenesis. Research during the past 30 years has expanded the roles of these proteins, first by discovering the ubiquitous expression of the trio and then by implicating them in a wide array of biological functions. In concert, these three hormones govern tissue development, homeostasis, and disease in multiple organ systems through diverse autocrine and paracrine mechanisms. In the present study, we have reviewed the actions of activin and its biological inhibitors, inhibin, and follistatin, in mammary gland morphogenesis and cancer.
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Affiliation(s)
- Darcie D Seachrist
- Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio
| | - Ruth A Keri
- Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, Ohio
- Division of General Medical Sciences–Oncology, Case Western Reserve University, Cleveland, Ohio
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Bloise E, Ciarmela P, Dela Cruz C, Luisi S, Petraglia F, Reis FM. Activin A in Mammalian Physiology. Physiol Rev 2019; 99:739-780. [DOI: 10.1152/physrev.00002.2018] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Activins are dimeric glycoproteins belonging to the transforming growth factor beta superfamily and resulting from the assembly of two beta subunits, which may also be combined with alpha subunits to form inhibins. Activins were discovered in 1986 following the isolation of inhibins from porcine follicular fluid, and were characterized as ovarian hormones that stimulate follicle stimulating hormone (FSH) release by the pituitary gland. In particular, activin A was shown to be the isoform of greater physiological importance in humans. The current understanding of activin A surpasses the reproductive system and allows its classification as a hormone, a growth factor, and a cytokine. In more than 30 yr of intense research, activin A was localized in female and male reproductive organs but also in other organs and systems as diverse as the brain, liver, lung, bone, and gut. Moreover, its roles include embryonic differentiation, trophoblast invasion of the uterine wall in early pregnancy, and fetal/neonate brain protection in hypoxic conditions. It is now recognized that activin A overexpression may be either cytostatic or mitogenic, depending on the cell type, with important implications for tumor biology. Activin A also regulates bone formation and regeneration, enhances joint inflammation in rheumatoid arthritis, and triggers pathogenic mechanisms in the respiratory system. In this 30-yr review, we analyze the evidence for physiological roles of activin A and the potential use of activin agonists and antagonists as therapeutic agents.
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Affiliation(s)
- Enrrico Bloise
- Department of Morphology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy; Department of Obstetrics and Gynecology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Department of Molecular and Developmental Medicine, Obstetrics and Gynecological Clinic, University of Siena, Siena, Italy; and Department of Biomedical, Experimental and Clinical Sciences, Division of Obstetrics and
| | - Pasquapina Ciarmela
- Department of Morphology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy; Department of Obstetrics and Gynecology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Department of Molecular and Developmental Medicine, Obstetrics and Gynecological Clinic, University of Siena, Siena, Italy; and Department of Biomedical, Experimental and Clinical Sciences, Division of Obstetrics and
| | - Cynthia Dela Cruz
- Department of Morphology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy; Department of Obstetrics and Gynecology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Department of Molecular and Developmental Medicine, Obstetrics and Gynecological Clinic, University of Siena, Siena, Italy; and Department of Biomedical, Experimental and Clinical Sciences, Division of Obstetrics and
| | - Stefano Luisi
- Department of Morphology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy; Department of Obstetrics and Gynecology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Department of Molecular and Developmental Medicine, Obstetrics and Gynecological Clinic, University of Siena, Siena, Italy; and Department of Biomedical, Experimental and Clinical Sciences, Division of Obstetrics and
| | - Felice Petraglia
- Department of Morphology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy; Department of Obstetrics and Gynecology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Department of Molecular and Developmental Medicine, Obstetrics and Gynecological Clinic, University of Siena, Siena, Italy; and Department of Biomedical, Experimental and Clinical Sciences, Division of Obstetrics and
| | - Fernando M. Reis
- Department of Morphology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy; Department of Obstetrics and Gynecology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Department of Molecular and Developmental Medicine, Obstetrics and Gynecological Clinic, University of Siena, Siena, Italy; and Department of Biomedical, Experimental and Clinical Sciences, Division of Obstetrics and
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Antsiferova M, Piwko-Czuchra A, Cangkrama M, Wietecha M, Sahin D, Birkner K, Amann VC, Levesque M, Hohl D, Dummer R, Werner S. Activin promotes skin carcinogenesis by attraction and reprogramming of macrophages. EMBO Mol Med 2017; 9:27-45. [PMID: 27932444 PMCID: PMC5210090 DOI: 10.15252/emmm.201606493] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Activin has emerged as an important player in different types of cancer, but the underlying mechanisms are largely unknown. We show here that activin overexpression is an early event in murine and human skin tumorigenesis. This is functionally important, since activin promoted skin tumorigenesis in mice induced by the human papillomavirus 8 oncogenes. This was accompanied by depletion of epidermal γδ T cells and accumulation of regulatory T cells. Most importantly, activin increased the number of skin macrophages via attraction of blood monocytes, which was prevented by depletion of CCR2‐positive monocytes. Gene expression profiling of macrophages from pre‐tumorigenic skin and bioinformatics analysis demonstrated that activin induces a gene expression pattern in skin macrophages that resembles the phenotype of tumor‐associated macrophages in different malignancies, thereby promoting angiogenesis, cell migration and proteolysis. The functional relevance of this finding was demonstrated by antibody‐mediated depletion of macrophages, which strongly suppressed activin‐induced skin tumor formation. These results demonstrate that activin induces skin carcinogenesis via attraction and reprogramming of macrophages and identify novel activin targets involved in tumor formation.
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Affiliation(s)
- Maria Antsiferova
- Department of Biology, Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland
| | | | - Michael Cangkrama
- Department of Biology, Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland
| | - Mateusz Wietecha
- Department of Biology, Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland
| | - Dilara Sahin
- Department of Biology, Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland
| | - Katharina Birkner
- Department of Biology, Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland
| | - Valerie C Amann
- Department of Dermatology, University Hospital, Zurich, Switzerland
| | | | - Daniel Hohl
- Department of Dermatology, University of Lausanne, Lausanne, Switzerland
| | - Reinhard Dummer
- Department of Dermatology, University Hospital, Zurich, Switzerland
| | - Sabine Werner
- Department of Biology, Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland
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25
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Walton KL, Johnson KE, Harrison CA. Targeting TGF-β Mediated SMAD Signaling for the Prevention of Fibrosis. Front Pharmacol 2017; 8:461. [PMID: 28769795 PMCID: PMC5509761 DOI: 10.3389/fphar.2017.00461] [Citation(s) in RCA: 384] [Impact Index Per Article: 54.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 06/27/2017] [Indexed: 01/18/2023] Open
Abstract
Fibrosis occurs when there is an imbalance in extracellular matrix (ECM) deposition and degradation. Excessive ECM deposition results in scarring and thickening of the affected tissue, and interferes with tissue and organ homeostasis – mimicking an exaggerated “wound healing” response. Many transforming growth factor-β (TGF-β) ligands are potent drivers of ECM deposition, and additionally, have a natural affinity for the ECM, creating a concentrated pool of pro-fibrotic factors at the site of injury. Consequently, TGF-β ligands are upregulated in many human fibrotic conditions and, as such, are attractive targets for fibrosis therapy. Here, we will discuss the contribution of TGF-β proteins in the pathogenesis of fibrosis, and promising anti-fibrotic approaches that target TGF-β ligands.
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Affiliation(s)
- Kelly L Walton
- Growth Factor Therapeutics Laboratory, Department of Physiology, Monash University, ClaytonVIC, Australia
| | - Katharine E Johnson
- Growth Factor Therapeutics Laboratory, Department of Physiology, Monash University, ClaytonVIC, Australia
| | - Craig A Harrison
- Growth Factor Therapeutics Laboratory, Department of Physiology, Monash University, ClaytonVIC, Australia
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26
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Specific targeting of TGF-β family ligands demonstrates distinct roles in the regulation of muscle mass in health and disease. Proc Natl Acad Sci U S A 2017; 114:E5266-E5275. [PMID: 28607086 DOI: 10.1073/pnas.1620013114] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The transforming growth factor-β (TGF-β) network of ligands and intracellular signaling proteins is a subject of intense interest within the field of skeletal muscle biology. To define the relative contribution of endogenous TGF-β proteins to the negative regulation of muscle mass via their activation of the Smad2/3 signaling axis, we used local injection of adeno-associated viral vectors (AAVs) encoding ligand-specific antagonists into the tibialis anterior (TA) muscles of C57BL/6 mice. Eight weeks after AAV injection, inhibition of activin A and activin B signaling produced moderate (∼20%), but significant, increases in TA mass, indicating that endogenous activins repress muscle growth. Inhibiting myostatin induced a more profound increase in muscle mass (∼45%), demonstrating a more prominent role for this ligand as a negative regulator of adult muscle mass. Remarkably, codelivery of activin and myostatin inhibitors induced a synergistic response, resulting in muscle mass increasing by as much as 150%. Transcription and protein analysis indicated that this substantial hypertrophy was associated with both the complete inhibition of the Smad2/3 pathway and activation of the parallel bone morphogenetic protein (BMP)/Smad1/5 axis (recently identified as a positive regulator of muscle mass). Analyses indicated that hypertrophy was primarily driven by an increase in protein synthesis, but a reduction in ubiquitin-dependent protein degradation pathways was also observed. In models of muscular dystrophy and cancer cachexia, combined inhibition of activins and myostatin increased mass or prevented muscle wasting, respectively, highlighting the potential therapeutic advantages of specifically targeting multiple Smad2/3-activating ligands in skeletal muscle.
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27
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Latres E, Mastaitis J, Fury W, Miloscio L, Trejos J, Pangilinan J, Okamoto H, Cavino K, Na E, Papatheodorou A, Willer T, Bai Y, Hae Kim J, Rafique A, Jaspers S, Stitt T, Murphy AJ, Yancopoulos GD, Gromada J. Activin A more prominently regulates muscle mass in primates than does GDF8. Nat Commun 2017; 8:15153. [PMID: 28452368 PMCID: PMC5414365 DOI: 10.1038/ncomms15153] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 03/06/2017] [Indexed: 12/19/2022] Open
Abstract
Growth and differentiation factor 8 (GDF8) is a TGF-β superfamily member, and negative regulator of skeletal muscle mass. GDF8 inhibition results in prominent muscle growth in mice, but less impressive hypertrophy in primates, including man. Broad TGF-β inhibition suggests another family member negatively regulates muscle mass, and its blockade enhances muscle growth seen with GDF8-specific inhibition. Here we show that activin A is the long-sought second negative muscle regulator. Activin A specific inhibition, on top of GDF8 inhibition, leads to pronounced muscle hypertrophy and force production in mice and monkeys. Inhibition of these two ligands mimics the hypertrophy seen with broad TGF-β blockers, while avoiding the adverse effects due to inhibition of multiple family members. Altogether, we identify activin A as a second negative regulator of muscle mass, and suggest that inhibition of both ligands provides a preferred therapeutic approach, which maximizes the benefit:risk ratio for muscle diseases in man. Inhibition of GDF8 increases muscle mass in mice, but is less effective in monkeys and humans. Here the authors show that activin A also inhibits muscle hypertrophy and that concomitant inhibition of activin A and GDF8 synergistically increases muscle mass in mice and non-human primates.
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Affiliation(s)
- Esther Latres
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Jason Mastaitis
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Wen Fury
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Lawrence Miloscio
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Jesus Trejos
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Jeffrey Pangilinan
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Haruka Okamoto
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Katie Cavino
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Erqian Na
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Angelos Papatheodorou
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Tobias Willer
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Yu Bai
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Jee Hae Kim
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Ashique Rafique
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Stephen Jaspers
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Trevor Stitt
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Andrew J Murphy
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - George D Yancopoulos
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Jesper Gromada
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591, USA
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Lidbury BA, Kita B, Lewis DP, Hayward S, Ludlow H, Hedger MP, de Kretser DM. Activin B is a novel biomarker for chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) diagnosis: a cross sectional study. J Transl Med 2017; 15:60. [PMID: 28302133 PMCID: PMC5353946 DOI: 10.1186/s12967-017-1161-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 03/10/2017] [Indexed: 12/15/2022] Open
Abstract
Background Investigations of activin family proteins as serum biomarkers for chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME). CFS/ME is a disease with complex, wide-ranging symptoms, featuring persistent fatigue of 6 months or longer, particularly post exertion. No definitive biomarkers are available. Methods A cross-sectional, observational study of CFS/ME patients fulfilling the 2003 Canadian Consensus Criteria, in parallel with healthy non-fatigued controls, was conducted. Comparisons with a previously defined activin reference population were also performed. For the total study cohort the age range was 18–65 years with a female: male participant ratio of greater than 3:1. All participants were assessed via a primary care community clinic. Blood samples were collected for pathology testing after physical examination and orthostatic intolerance assessment. Cytokines, activin A, activin B and follistatin were also measured in sera from these samples. All data were compared between the CFS/ME and control cohorts, with the activins and follistatin also compared with previously defined reference intervals. Results Serum activin B levels for CFS/ME participants were significantly elevated when compared to the study controls, as well as the established reference interval. Serum activin A and follistatin were within their normal ranges. All routine and special pathology markers were within the normal laboratory reference intervals for the total study cohort, with no significant differences detected between CFS/ME and control groups. Also, no significant differences were detected for IL-2, IL-4, IL-6, IL-10, IL-17A, TNF or IFN-gamma. Conclusion Elevated activin B levels together with normal activin A levels identified patients with the diagnostic symptoms of CFS/ME, thus providing a novel serum based test. The activins have multiple physiological roles and capture the diverse array of symptoms experienced by CFS/ME patients.
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Affiliation(s)
- Brett A Lidbury
- Pattern Recognition and Pathology, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, 2601, Australia. .,The National Centre for Epidemiology and Public Health, The Research School of Population Health, ANU, Canberra, ACT, 2601, Australia.
| | - Badia Kita
- Paranta Biosciences Limited, Caulfield North, VIC, 3161, Australia
| | - Donald P Lewis
- CFS Discovery, Donvale Medical Specialist Centre, Donvale, VIC, 3111, Australia
| | - Susan Hayward
- The Hudson Medical Research Institute, Monash University, Clayton, VIC, 3168, Australia
| | - Helen Ludlow
- Centre for Proteins and Peptides, School of Life Sciences, Oxford Brookes University, Headington, Oxford, OX3 0BP, UK
| | - Mark P Hedger
- The Hudson Medical Research Institute, Monash University, Clayton, VIC, 3168, Australia
| | - David M de Kretser
- The Hudson Medical Research Institute, Monash University, Clayton, VIC, 3168, Australia.,Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, 3168, Australia
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Puolakkainen T, Ma H, Kainulainen H, Pasternack A, Rantalainen T, Ritvos O, Heikinheimo K, Hulmi JJ, Kiviranta R. Treatment with soluble activin type IIB-receptor improves bone mass and strength in a mouse model of Duchenne muscular dystrophy. BMC Musculoskelet Disord 2017; 18:20. [PMID: 28103859 PMCID: PMC5244551 DOI: 10.1186/s12891-016-1366-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 12/14/2016] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Inhibition of activin/myostatin pathway has emerged as a novel approach to increase muscle mass and bone strength. Duchenne muscular dystrophy (DMD) is a neuromuscular disorder that leads to progressive muscle degeneration and also high incidence of fractures. The aim of our study was to test whether inhibition of activin receptor IIB ligands with or without exercise could improve bone strength in the mdx mouse model for DMD. METHODS Thirty-two mdx mice were divided to running and non-running groups and to receive either PBS control or soluble activin type IIB-receptor (ActRIIB-Fc) once weekly for 7 weeks. RESULTS Treatment of mdx mice with ActRIIB-Fc resulted in significantly increased body and muscle weights in both sedentary and exercising mice. Femoral μCT analysis showed increased bone volume and trabecular number (BV/TV +80%, Tb.N +70%, P < 0.05) in both ActRIIB-Fc treated groups. Running also resulted in increased bone volume and trabecular number in PBS-treated mice. However, there was no significant difference in trabecular bone structure or volumetric bone mineral density between the ActRIIB-Fc and ActRIIB-Fc-R indicating that running did not further improve bone structure in ActRIIB-Fc-treated mice. ActRIIB-Fc increased bone mass also in vertebrae (BV/TV +20%, Tb.N +30%, P < 0.05) but the effects were more modest. The number of osteoclasts was decreased in histological analysis and the expression of several osteoblast marker genes was increased in ActRIIB-Fc treated mice suggesting decreased bone resorption and increased bone formation in these mice. Increased bone mass in femurs translated into enhanced bone strength in biomechanical testing as the maximum force and stiffness were significantly elevated in ActRIIB-Fc-treated mice. CONCLUSIONS Our results indicate that treatment of mdx mice with the soluble ActRIIB-Fc results in a robust increase in bone mass, without any additive effect by voluntary running. Thus ActRIIB-Fc could be an attractive option in the treatment of musculoskeletal disorders.
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Affiliation(s)
- Tero Puolakkainen
- Department of Medical Biochemistry and Genetics, University of Turku, Kiinamyllynkatu 10, FI-20520, Turku, Finland
| | - Hongqian Ma
- Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland.,Institute of Dentistry, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Heikki Kainulainen
- Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
| | - Arja Pasternack
- Department of Physiology, University of Helsinki, Helsinki, Finland
| | - Timo Rantalainen
- Centre for Physical Activity and Nutrition Research, Deakin University, Melbourne, Australia
| | - Olli Ritvos
- Department of Physiology, University of Helsinki, Helsinki, Finland
| | - Kristiina Heikinheimo
- Department of Oral and Maxillofacial Surgery, Institute of Dentistry, University of Turku, Turku, Finland.,Department of Oral Diagnostic Sciences, Institute of Dentistry, University of Eastern Finland, Kuopio, Finland.,Kuopio University Hospital, Kuopio, Finland
| | - Juha J Hulmi
- Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland.,Department of Physiology, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Riku Kiviranta
- Department of Medical Biochemistry and Genetics, University of Turku, Kiinamyllynkatu 10, FI-20520, Turku, Finland. .,Department of Endocrinology, Turku University Hospital, Turku, Finland.
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31
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Chen JL, Colgan TD, Walton KL, Gregorevic P, Harrison CA. The TGF-β Signalling Network in Muscle Development, Adaptation and Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 900:97-131. [PMID: 27003398 DOI: 10.1007/978-3-319-27511-6_5] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Skeletal muscle possesses remarkable ability to change its size and force-producing capacity in response to physiological stimuli. Impairment of the cellular processes that govern these attributes also affects muscle mass and function in pathological conditions. Myostatin, a member of the TGF-β family, has been identified as a key regulator of muscle development, and adaptation in adulthood. In muscle, myostatin binds to its type I (ALK4/5) and type II (ActRIIA/B) receptors to initiate Smad2/3 signalling and the regulation of target genes that co-ordinate the balance between protein synthesis and degradation. Interestingly, evidence is emerging that other TGF-β proteins act in concert with myostatin to regulate the growth and remodelling of skeletal muscle. Consequently, dysregulation of TGF-β proteins and their associated signalling components is increasingly being implicated in muscle wasting associated with chronic illness, ageing, and inactivity. The growing understanding of TGF-β biology in muscle, and its potential to advance the development of therapeutics for muscle-related conditions is reviewed here.
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Affiliation(s)
- Justin L Chen
- Centre for Endocrinology and Metabolism, Hudson Institute of Medical Research, Clayton, VIC, 3168, Australia.,Department of Molecular and Translational Sciences, Monash University, Melbourne, VIC, Australia.,Muscle Research and Therapeutics Development, Baker IDI Heart and Diabetes Institute, Melbourne, VIC, 3004, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Melbourne, VIC, Australia
| | - Timothy D Colgan
- Muscle Research and Therapeutics Development, Baker IDI Heart and Diabetes Institute, Melbourne, VIC, 3004, Australia.,Department of Physiology, The University of Melbourne, Melbourne, VIC, Australia
| | - Kelly L Walton
- Centre for Endocrinology and Metabolism, Hudson Institute of Medical Research, Clayton, VIC, 3168, Australia.,Department of Molecular and Translational Sciences, Monash University, Melbourne, VIC, Australia
| | - Paul Gregorevic
- Muscle Research and Therapeutics Development, Baker IDI Heart and Diabetes Institute, Melbourne, VIC, 3004, Australia. .,Department of Biochemistry and Molecular Biology, Monash University, Melbourne, VIC, Australia. .,Department of Physiology, The University of Melbourne, Melbourne, VIC, Australia. .,Department of Neurology, School of Medicine, The University of Washington, Seattle, WA, USA.
| | - Craig A Harrison
- Centre for Endocrinology and Metabolism, Hudson Institute of Medical Research, Clayton, VIC, 3168, Australia. .,Department of Molecular and Translational Sciences, Monash University, Melbourne, VIC, Australia. .,Department of Physiology, Monash University, Melbourne, VIC, Australia.
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Laurent MR, Dubois V, Claessens F, Verschueren SMP, Vanderschueren D, Gielen E, Jardí F. Muscle-bone interactions: From experimental models to the clinic? A critical update. Mol Cell Endocrinol 2016; 432:14-36. [PMID: 26506009 DOI: 10.1016/j.mce.2015.10.017] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 10/13/2015] [Accepted: 10/20/2015] [Indexed: 02/06/2023]
Abstract
Bone is a biomechanical tissue shaped by forces from muscles and gravitation. Simultaneous bone and muscle decay and dysfunction (osteosarcopenia or sarco-osteoporosis) is seen in ageing, numerous clinical situations including after stroke or paralysis, in neuromuscular dystrophies, glucocorticoid excess, or in association with vitamin D, growth hormone/insulin like growth factor or sex steroid deficiency, as well as in spaceflight. Physical exercise may be beneficial in these situations, but further work is still needed to translate acceptable and effective biomechanical interventions like vibration therapy from animal models to humans. Novel antiresorptive and anabolic therapies are emerging for osteoporosis as well as drugs for sarcopenia, cancer cachexia or muscle wasting disorders, including antibodies against myostatin or activin receptor type IIA and IIB (e.g. bimagrumab). Ideally, increasing muscle mass would increase muscle strength and restore bone loss from disuse. However, the classical view that muscle is unidirectionally dominant over bone via mechanical loading is overly simplistic. Indeed, recent studies indicate a role for neuronal regulation of not only muscle but also bone metabolism, bone signaling pathways like receptor activator of nuclear factor kappa-B ligand (RANKL) implicated in muscle biology, myokines affecting bone and possible bone-to-muscle communication. Moreover, pharmacological strategies inducing isolated myocyte hypertrophy may not translate into increased muscle power because tendons, connective tissue, neurons and energy metabolism need to adapt as well. We aim here to critically review key musculoskeletal molecular pathways involved in mechanoregulation and their effect on the bone-muscle unit as a whole, as well as preclinical and emerging clinical evidence regarding the effects of sarcopenia therapies on osteoporosis and vice versa.
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Affiliation(s)
- Michaël R Laurent
- Gerontology and Geriatrics, Department of Clinical and Experimental Medicine, KU Leuven, 3000 Leuven, Belgium; Laboratory of Molecular Endocrinology, Department of Cellular and Molecular Medicine, KU Leuven, 3000 Leuven, Belgium; Centre for Metabolic Bone Diseases, University Hospitals Leuven, 3000 Leuven, Belgium.
| | - Vanessa Dubois
- Laboratory of Molecular Endocrinology, Department of Cellular and Molecular Medicine, KU Leuven, 3000 Leuven, Belgium
| | - Frank Claessens
- Laboratory of Molecular Endocrinology, Department of Cellular and Molecular Medicine, KU Leuven, 3000 Leuven, Belgium
| | - Sabine M P Verschueren
- Research Group for Musculoskeletal Rehabilitation, Department of Rehabilitation Science, KU Leuven, 3000 Leuven, Belgium
| | - Dirk Vanderschueren
- Clinical and Experimental Endocrinology, Department of Clinical and Experimental Medicine, KU Leuven, 3000 Leuven, Belgium
| | - Evelien Gielen
- Gerontology and Geriatrics, Department of Clinical and Experimental Medicine, KU Leuven, 3000 Leuven, Belgium; Centre for Metabolic Bone Diseases, University Hospitals Leuven, 3000 Leuven, Belgium
| | - Ferran Jardí
- Clinical and Experimental Endocrinology, Department of Clinical and Experimental Medicine, KU Leuven, 3000 Leuven, Belgium
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Namwanje M, Brown CW. Activins and Inhibins: Roles in Development, Physiology, and Disease. Cold Spring Harb Perspect Biol 2016; 8:cshperspect.a021881. [PMID: 27328872 DOI: 10.1101/cshperspect.a021881] [Citation(s) in RCA: 155] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Since their original discovery as regulators of follicle-stimulating hormone (FSH) secretion and erythropoiesis, the TGF-β family members activin and inhibin have been shown to participate in a variety of biological processes, from the earliest stages of embryonic development to highly specialized functions in terminally differentiated cells and tissues. Herein, we present the history, structures, signaling mechanisms, regulation, and biological processes in which activins and inhibins participate, including several recently discovered biological activities and functional antagonists. The potential therapeutic relevance of these advances is also discussed.
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Affiliation(s)
- Maria Namwanje
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
| | - Chester W Brown
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030 Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030 Texas Children's Hospital, Houston, Texas 77030
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Chen JL, Walton KL, Qian H, Colgan TD, Hagg A, Watt MJ, Harrison CA, Gregorevic P. Differential Effects of IL6 and Activin A in the Development of Cancer-Associated Cachexia. Cancer Res 2016; 76:5372-82. [PMID: 27328730 DOI: 10.1158/0008-5472.can-15-3152] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 06/13/2016] [Indexed: 11/16/2022]
Abstract
Cachexia is a life-threatening wasting syndrome lacking effective treatment, which arises in many cancer patients. Although ostensibly induced by multiple tumor-produced cytokines (tumorkines), their functional contribution to initiation and progression of this syndrome has proven difficult to determine. In this study, we used adeno-associated viral vectors to elevate circulating levels of the tumorkines IL6 and/or activin A in animals in the absence of tumors as a tactic to evaluate hypothesized roles in cachexia development. Mice with elevated levels of IL6 exhibited 8.1% weight loss after 9 weeks, whereas mice with elevated levels of activin A lost 11% of their body weight. Co-elevation of both tumorkines to levels approximating those observed in cancer cachexia models induced a more rapid and profound body weight loss of 15.4%. Analysis of body composition revealed that activin A primarily triggered loss of lean mass, whereas IL6 was a major mediator of fat loss. Histologic and transcriptional analysis of affected organs/tissues (skeletal muscle, fat, and liver) identified interactions between the activin A and IL6 signaling pathways. For example, IL6 exacerbated the detrimental effects of activin A in skeletal muscle, whereas activin A curbed the IL6-induced acute-phase response in liver. This study presents a useful model to deconstruct cachexia, opening a pathway to determining which tumorkines are best targeted to slow/reverse this devastating condition in cancer patients. Cancer Res; 76(18); 5372-82. ©2016 AACR.
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Affiliation(s)
- Justin L Chen
- Hudson Institute of Medical Research, Clayton, Australia. Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Kelly L Walton
- Hudson Institute of Medical Research, Clayton, Australia
| | - Hongwei Qian
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Timothy D Colgan
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia. Department of Physiology, The University of Melbourne, Melbourne, Australia
| | - Adam Hagg
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Matthew J Watt
- The Obesity and Metabolism Program of the Biomedicine Discovery Institute, Monash University, Clayton, Australia. Department of Physiology, Monash University, Clayton, Australia
| | - Craig A Harrison
- Hudson Institute of Medical Research, Clayton, Australia. Department of Physiology, Monash University, Clayton, Australia. Department of Molecular and Translational Sciences, Monash University, Clayton, Australia
| | - Paul Gregorevic
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia. Department of Physiology, The University of Melbourne, Melbourne, Australia. Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia. Department of Neurology, The University of Washington School of Medicine, Seattle, Washington.
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Sanchez-Duffhues G, Fotsis T, ten Dijke P. Signal Transduction: Gain of Activin Turns Muscle into Bone. Curr Biol 2016; 25:R1136-8. [PMID: 26654374 DOI: 10.1016/j.cub.2015.10.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Recent data provide an unexpected twist in our understanding of the pathogenesis of fibrodysplasia ossificans progressiva. Surprisingly, the causative amino acid mutation of the BMP receptor responds to activin, thereby turning soft tissues into bone.
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Affiliation(s)
- Gonzalo Sanchez-Duffhues
- Department of Molecular Cell Biology, Cancer Genomics Centre Netherlands, Leiden University Medical Center, The Netherlands
| | - Theodore Fotsis
- Department of Biomedical Research, Institute of Molecular Biology & Biotechnology, FORTH & Laboratory of Biological Chemistry, Medical School, University of Ioannina, University Campus, University of Ioannina, 45110 Ioannina, Greece. Currently: Visiting Professor, School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Peter ten Dijke
- Department of Molecular Cell Biology, Cancer Genomics Centre Netherlands, Leiden University Medical Center, The Netherlands.
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Voisin S, Guilherme JPFL, Yan X, Pushkarev VP, Cieszczyk P, Massidda M, Calò CM, Dyatlov DA, Kolupaev VA, Pushkareva YE, Maciejewska A, Sawczuk M, Lancha AH, Artioli GG, Eynon N. ACVR1B rs2854464 Is Associated with Sprint/Power Athletic Status in a Large Cohort of Europeans but Not Brazilians. PLoS One 2016; 11:e0156316. [PMID: 27253421 PMCID: PMC4890799 DOI: 10.1371/journal.pone.0156316] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 05/12/2016] [Indexed: 11/18/2022] Open
Abstract
Skeletal muscle strength and mass, major contributors to sprint/power athletic performance, are influenced by genetics. However, to date, only a handful of genetic variants have been associated with sprint/power performance. The ACVR1B A allele (rs rs2854464) has previously been associated with increased muscle-strength in non-athletic cohort. However, no follow-up and/or replications studies have since been conducted. Therefore, the aim of the present study was to compare the genotype distribution of ACVR1B rs2854464 between endurance athletes (E), sprint/power (S/P) athletes, mixed athletes (M), and non-athletic control participants in 1672 athletes (endurance athletes, n = 482; sprint/power athletes, n = 578; mixed athletes, n = 498) and 1089 controls (C) of both European Caucasians (Italian, Polish and Russians) and Brazilians. We have also compared the genotype distribution according to the athlete's level of competition (elite vs. sub-elite). DNA extraction and genotyping were performed using various methods. Fisher's exact test (adjusted for multiple comparisons) was used to test whether the genotype distribution of rs2854464 (AA, AG and GG) differs between groups. The A allele was overrepresented in S/P athletes compared with C in the Caucasian sample (adjusted p = 0.048), whereas there were no differences in genotype distribution between E athletes and C, in neither the Brazilian nor the Caucasian samples (adjusted p > 0.05). When comparing all Caucasian athletes regardless of their sporting discipline to C, we found that the A allele was overrepresented in athletes compared to C (adjusted p = 0.024). This association was even more pronounced when only elite-level athletes were considered (adjusted p = 0.00017). In conclusion, in a relatively large cohort of athletes from Europe and South America we have shown that the ACVR1B rs2854464 A allele is associated with sprint/power performance in Caucasians but not in Brazilian athletes. This reinforces the notion that phenotype-genotype associations may be ethnicity-dependent.
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Affiliation(s)
- Sarah Voisin
- INRA, UMR1198 Biologie du Développement et Reproduction, F-78350, Jouy-en-Josas, France
- Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, Victoria, Melbourne, Australia
| | | | - Xu Yan
- Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, Victoria, Melbourne, Australia
| | - Vladimir P. Pushkarev
- Laboratory of Radiation Genetics, Urals Research Centre for Radiation Medicine of the Federal Medical-Biological Agency of Russia, Chelyabinsk, Russia
- Department of Radiation Biology, Chelyabinsk State University, Chelyabinsk, Russia
| | - Pawel Cieszczyk
- Academy of Physical Education and Sport, Department of Tourism and Recreation, Gdansk, Poland
- Department of Physical Culture and Health Promotion, University of Szczecin, Szczecin Poland
| | - Myosotis Massidda
- Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
| | - Carla M. Calò
- Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
| | | | | | | | - Agnieszka Maciejewska
- Department of Physical Culture and Health Promotion, University of Szczecin, Szczecin Poland
| | - Marek Sawczuk
- Department of Physical Culture and Health Promotion, University of Szczecin, Szczecin Poland
| | - Antonio H. Lancha
- School of Physical Education and Sport, University of Sao Paulo, Sao Paulo, Brazil
| | - Guilherme G. Artioli
- School of Physical Education and Sport, University of Sao Paulo, Sao Paulo, Brazil
| | - Nir Eynon
- Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, Victoria, Melbourne, Australia
- * E-mail:
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Davey JR, Watt KI, Parker BL, Chaudhuri R, Ryall JG, Cunningham L, Qian H, Sartorelli V, Sandri M, Chamberlain J, James DE, Gregorevic P. Integrated expression analysis of muscle hypertrophy identifies Asb2 as a negative regulator of muscle mass. JCI Insight 2016; 1. [PMID: 27182554 DOI: 10.1172/jci.insight.85477] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The transforming growth factor-β (TGF-β) signaling network is a critical regulator of skeletal muscle mass and function and, thus, is an attractive therapeutic target for combating muscle disease, but the underlying mechanisms of action remain undetermined. We report that follistatin-based interventions (which modulate TGF-β network activity) can promote muscle hypertrophy that ameliorates aging-associated muscle wasting. However, the muscles of old sarcopenic mice demonstrate reduced response to follistatin compared with healthy young-adult musculature. Quantitative proteomic and transcriptomic analyses of young-adult muscles identified a transcription/translation signature elicited by follistatin exposure, which included repression of ankyrin repeat and SOCS box protein 2 (Asb2). Increasing expression of ASB2 reduced muscle mass, thereby demonstrating that Asb2 is a TGF-β network-responsive negative regulator of muscle mass. In contrast to young-adult muscles, sarcopenic muscles do not exhibit reduced ASB2 abundance with follistatin exposure. Moreover, preventing repression of ASB2 in young-adult muscles diminished follistatin-induced muscle hypertrophy. These findings provide insight into the program of transcription and translation events governing follistatin-mediated adaptation of skeletal muscle attributes and identify Asb2 as a regulator of muscle mass implicated in the potential mechanistic dysfunction between follistatin-mediated muscle growth in young and old muscles.
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Affiliation(s)
| | - Kevin I Watt
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Benjamin L Parker
- Charles Perkins Centre, School of Molecular Bioscience, The University of Sydney, Sydney, Australia
| | - Rima Chaudhuri
- Charles Perkins Centre, School of Molecular Bioscience, The University of Sydney, Sydney, Australia
| | - James G Ryall
- National Institute of Arthritis Musculoskeletal and Skin Diseases (NIAMS), NIH, Bethesda, Maryland, USA; Department of Physiology, The University of Melbourne, Melbourne, Australia
| | | | - Hongwei Qian
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Vittorio Sartorelli
- National Institute of Arthritis Musculoskeletal and Skin Diseases (NIAMS), NIH, Bethesda, Maryland, USA
| | - Marco Sandri
- Venetian Institute of Molecular Medicine, The University of Padova, Padova, Italy
| | - Jeffrey Chamberlain
- Department of Neurology, The University of Washington, Seattle, Washington, USA
| | - David E James
- Charles Perkins Centre, School of Molecular Bioscience, The University of Sydney, Sydney, Australia; Sydney Medical School, The University of Sydney, Sydney, Australia
| | - Paul Gregorevic
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia; Department of Physiology, The University of Melbourne, Melbourne, Australia; Department of Neurology, The University of Washington, Seattle, Washington, USA; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
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Wijayarathna R, de Kretser DM. Activins in reproductive biology and beyond. Hum Reprod Update 2016; 22:342-57. [PMID: 26884470 DOI: 10.1093/humupd/dmv058] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 11/20/2015] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Activins are members of the pleiotrophic family of the transforming growth factor-beta (TGF-β) superfamily of cytokines, initially isolated for their capacity to induce the release of FSH from pituitary extracts. Subsequent research has demonstrated that activins are involved in multiple biological functions including the control of inflammation, fibrosis, developmental biology and tumourigenesis. This review summarizes the current knowledge on the roles of activin in reproductive and developmental biology. It also discusses interesting advances in the field of modulating the bioactivity of activins as a therapeutic target, which would undoubtedly be beneficial for patients with reproductive pathology. METHODS A comprehensive literature search was carried out using PUBMED and Google Scholar databases to identify studies in the English language which have contributed to the advancement of the field of activin biology, since its initial isolation in 1987 until July 2015. 'Activin', 'testis', 'ovary', 'embryonic development' and 'therapeutic targets' were used as the keywords in combination with other search phrases relevant to the topic of activin biology. RESULTS Activins, which are dimers of inhibin β subunits, act via a classical TGF-β signalling pathway. The bioactivity of activin is regulated by two endogenous inhibitors, inhibin and follistatin. Activin is a major regulator of testicular and ovarian development. In the ovary, activin A promotes oocyte maturation and regulates granulosa cell steroidogenesis. It is also essential in endometrial repair following menstruation, decidualization and maintaining pregnancy. Dysregulation of the activin-follistatin-inhibin system leads to disorders of female reproduction and pregnancy, including polycystic ovary syndrome, ectopic pregnancy, miscarriage, fetal growth restriction, gestational diabetes, pre-eclampsia and pre-term birth. Moreover, a rise in serum activin A, accompanied by elevated FSH, is characteristic of female reproductive aging. In the male, activin A is an autocrine and paracrine modulator of germ cell development and Sertoli cell proliferation. Disruption of normal activin signalling is characteristic of many tumours affecting reproductive organs, including endometrial carcinoma, cervical cancer, testicular and ovarian cancer as well as prostate cancer. While activin A and B aid the progression of many tumours of the reproductive organs, activin C acts as a tumour suppressor. Activins are important in embryonic induction, morphogenesis of branched glandular organs, development of limbs and nervous system, craniofacial and dental development and morphogenesis of the Wolffian duct. CONCLUSIONS The field of activin biology has advanced considerably since its initial discovery as an FSH stimulating agent. Now, activin is well known as a growth factor and cytokine that regulates many aspects of reproductive biology, developmental biology and also inflammation and immunological mechanisms. Current research provides evidence for novel roles of activins in maintaining the structure and function of reproductive and other organ systems. The fact that activin A is elevated both locally as well as systemically in major disorders of the reproductive system makes it an important biomarker. Given the established role of activin A as a pro-inflammatory and pro-fibrotic agent, studies of its involvement in disorders of reproduction resulting from these processes should be examined. Follistatin, as a key regulator of the biological actions of activin, should be evaluated as a therapeutic agent in conditions where activin A overexpression is established as a contributing factor.
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Affiliation(s)
- R Wijayarathna
- Department of Anatomy and Developmental Biology, Monash University, Wellington Road, Clayton, VIC 3800, Australia Centre for Reproductive Health, Hudson Institute of Medical Research, 27-31, Wright Street, Clayton, VIC 3168, Australia
| | - D M de Kretser
- Department of Anatomy and Developmental Biology, Monash University, Wellington Road, Clayton, VIC 3800, Australia Centre for Reproductive Health, Hudson Institute of Medical Research, 27-31, Wright Street, Clayton, VIC 3168, Australia
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Johnson KE, Makanji Y, Temple-Smith P, Kelly EK, Barton PA, Al-Musawi SL, Mueller TD, Walton KL, Harrison CA. Biological activity and in vivo half-life of pro-activin A in male rats. Mol Cell Endocrinol 2016; 422:84-92. [PMID: 26687063 DOI: 10.1016/j.mce.2015.12.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 12/07/2015] [Accepted: 12/07/2015] [Indexed: 01/01/2023]
Abstract
Mature TGF-β proteins are used in vivo to promote bone growth, combat obesity, reverse fibrosis and pulmonary arterial hypertension, and as potential rejuvenation factors. However, the serum half-life of this family of growth factors is short (∼5 min), limiting their therapeutic potential. Because TGF-β proteins are normally secreted from cells with their prodomains attached, we considered whether these molecules could extend the in vivo half-life and activity of their respective growth factors. Using activin A as a model ligand, we initially modified the cleavage site between the pro- and mature domains to ensure complete processing of the activin A precursor. Co-immunoprecipitation studies confirmed mature activin A is secreted from cells in a non-covalent complex with its prodomain, however, the affinity of this interaction is not sufficient to suppress activin A in vitro biological activity. The plasma clearance profiles of purified pro- and mature activin A were determined over a 4 h period in adult male rats. Both activin forms demonstrated a two-phase decay, with the half-life of pro-activin A (t1/2 fast = 12.5 min, slow = 31.0 min) being greater than that of mature activin A (t1/2 fast = 5.5 min, slow = 20.3 min). Both pro- and mature activin A induced significant increases in serum follicle stimulating hormone levels after 4 h, but no differences were observed in the relative in vivo bioactivities of the two activin isoforms. Increased serum half-life of activin A in the presence of its prodomain identifies a new means to increase the therapeutic effectiveness of TGF-β proteins.
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Affiliation(s)
- Katharine E Johnson
- Hudson Institute of Medical Research, Clayton, VIC 3168, Australia; Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
| | | | - Peter Temple-Smith
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC 3800, Australia
| | - Emily K Kelly
- Hudson Institute of Medical Research, Clayton, VIC 3168, Australia
| | - Peter A Barton
- Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
| | - Sara L Al-Musawi
- Hudson Institute of Medical Research, Clayton, VIC 3168, Australia; Department of Molecular and Translational Science, Monash University, Clayton, VIC 3800, Australia
| | - Thomas D Mueller
- Department of Plant Physiology and Biophysics, Julius-von-Sachs Institute of the University Wuerzburg, Julius-von Sachs Platz 2, Wuerzburg, Germany
| | - Kelly L Walton
- Hudson Institute of Medical Research, Clayton, VIC 3168, Australia; Department of Molecular and Translational Science, Monash University, Clayton, VIC 3800, Australia
| | - Craig A Harrison
- Hudson Institute of Medical Research, Clayton, VIC 3168, Australia; Department of Molecular and Translational Science, Monash University, Clayton, VIC 3800, Australia.
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Evaluation of follistatin as a therapeutic in models of skeletal muscle atrophy associated with denervation and tenotomy. Sci Rep 2015; 5:17535. [PMID: 26657343 PMCID: PMC4675991 DOI: 10.1038/srep17535] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 11/02/2015] [Indexed: 01/25/2023] Open
Abstract
Follistatin is an inhibitor of TGF-β superfamily ligands that repress skeletal muscle growth and promote muscle wasting. Accordingly, follistatin has emerged as a potential therapeutic to ameliorate the deleterious effects of muscle atrophy. However, it remains unclear whether the anabolic effects of follistatin are conserved across different modes of non-degenerative muscle wasting. In this study, the delivery of a recombinant adeno-associated viral vector expressing follistatin (rAAV:Fst) to the hind-limb musculature of mice two weeks prior to denervation or tenotomy promoted muscle hypertrophy that was sufficient to preserve muscle mass comparable to that of untreated sham-operated muscles. However, administration of rAAV:Fst to muscles at the time of denervation or tenotomy did not prevent subsequent muscle wasting. Administration of rAAV:Fst to innervated or denervated muscles increased protein synthesis, but markedly reduced protein degradation only in innervated muscles. Phosphorylation of the signalling proteins mTOR and S6RP, which are associated with protein synthesis, was increased in innervated muscles administered rAAV:Fst, but not in treated denervated muscles. These results demonstrate that the anabolic effects of follistatin are influenced by the interaction between muscle fibres and motor nerves. These findings have important implications for understanding the potential efficacy of follistatin-based therapies for non-degenerative muscle wasting.
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