1
|
The Effects of Mechanical Loading Variations on the Hypertrophic, Anti-Apoptotic, and Anti-Inflammatory Responses of Differentiated Cardiomyocyte-like H9C2 Cells. Cells 2022; 11:cells11030473. [PMID: 35159283 PMCID: PMC8834179 DOI: 10.3390/cells11030473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/25/2021] [Accepted: 01/26/2022] [Indexed: 11/28/2022] Open
Abstract
Cardiomyocytes possess the ability to respond to mechanical stimuli by adapting their biological functions. This study investigated cellular and molecular events in cardiomyocyte-like H9C2 cells during differentiation as well as the signalling and gene expression responses of the differentiated cells under various mechanical stretching protocols in vitro. Immunofluorescence was used to monitor MyHC expression and structural changes during cardiomyoblast differentiation. Moreover, alterations in the expression of cardiac-specific markers, cell cycle regulatory factors, MRFs, hypertrophic, apoptotic, atrophy and inflammatory factors, as well as the activation of major intracellular signalling pathways were evaluated during differentiation and under mechanical stretching of the differentiated H9C2 cells. Compared to undifferentiated cells, advanced-differentiation cardiomyoblasts exhibited increased expression of cardiac-specific markers, MyHC, MRFs, and IGF-1 isoforms. Moreover, differentiated cells that underwent a low strain/frequency mechanical loading protocol of intermediate duration showed enhanced expression of MRFs and hypertrophic factors, along with a decreased expression of apoptotic, atrophy, and inflammatory factors compared to both high-strain/frequency loading protocols and to unloaded cells. These findings suggest that altering the strain and frequency of mechanical loading applied on differentiated H9C2 cardiomyoblasts can regulate their anabolic/survival program, with a low-strain/frequency stretching being, overall, most effective at inducing beneficial responses.
Collapse
|
2
|
Moustogiannis A, Philippou A, Taso O, Zevolis E, Pappa M, Chatzigeorgiou A, Koutsilieris M. The Effects of Muscle Cell Aging on Myogenesis. Int J Mol Sci 2021; 22:ijms22073721. [PMID: 33918414 PMCID: PMC8038215 DOI: 10.3390/ijms22073721] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 03/30/2021] [Accepted: 03/31/2021] [Indexed: 02/06/2023] Open
Abstract
The process of myogenesis gradually deteriorates as the skeletal muscle ages, contributing to muscle mass loss. The aim of this study is to investigate the effect of senescence/aging on skeletal myogenesis, in vitro. A model of multiple cell divisions of C2C12 myoblasts was used to replicate cell senescence. Control and aged myoblasts were investigated during myogenesis, i.e., at days 0, 2, and 6of differentiation. SA-β-gal activity and comet assay were used as markers of aging and DNA damage. Flow cytometry was performed to characterize potential differences in cell cycle between control and aged cells. Alterations in the mRNA and/or protein expression of myogenic regulatory factors (MRFs), IGF-1 isoforms, apoptotic, atrophy, inflammatory, metabolic and aging-related factors were evaluated. Compared with the control cells, aged myoblasts exhibited G0/G1 cell cycle arrest, DNA damage, increased SA-β-gal activity, and increased expression of aging-related factors p16 and p21 during differentiation. Moreover, aged myoblasts showed a reduction in the expression of MRFs and metabolic/anabolic factors, along with an increased expression of apoptotic, atrophy and inflammatory factors. A diminished differentiation capacity characterized the aged myoblasts which, in combination with the induction of apoptotic and atrophy factors, indicated a disrupted myogenic lineage in the senescent muscle cells.
Collapse
Affiliation(s)
- Athanasios Moustogiannis
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 MicrasAsias, 115 27 Goudi-Athens, Greece; (A.P.); (O.T.); (E.Z.); (A.C.); (M.K.)
- Correspondence: ; Tel.: +30-210-7462690; Fax: +30-210-7462571
| | - Anastassios Philippou
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 MicrasAsias, 115 27 Goudi-Athens, Greece; (A.P.); (O.T.); (E.Z.); (A.C.); (M.K.)
| | - Orjona Taso
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 MicrasAsias, 115 27 Goudi-Athens, Greece; (A.P.); (O.T.); (E.Z.); (A.C.); (M.K.)
| | - Evangelos Zevolis
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 MicrasAsias, 115 27 Goudi-Athens, Greece; (A.P.); (O.T.); (E.Z.); (A.C.); (M.K.)
| | - Maria Pappa
- First Department of Propaedeutic Internal Medicine, Joint Rheumatology Program, National and Kapodistrian University of Athens, 75 MicrasAsias, 115 27 Goudi-Athens, Greece;
| | - Antonios Chatzigeorgiou
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 MicrasAsias, 115 27 Goudi-Athens, Greece; (A.P.); (O.T.); (E.Z.); (A.C.); (M.K.)
| | - Michael Koutsilieris
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 MicrasAsias, 115 27 Goudi-Athens, Greece; (A.P.); (O.T.); (E.Z.); (A.C.); (M.K.)
| |
Collapse
|
3
|
Stavropoulos A, Varras M, Philippou A, Vasilakaki T, Varra VK, Varra FN, Tsavari A, Lazaris AC, Koutsilieris M. Immunohistochemical expression of insulin-like growth factor-1Ec in primary endometrial carcinoma: Association with PTEN, p53 and survivin expression. Oncol Lett 2020; 20:395. [PMID: 33193855 PMCID: PMC7656117 DOI: 10.3892/ol.2020.12258] [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: 04/03/2020] [Accepted: 09/16/2020] [Indexed: 12/21/2022] Open
Abstract
Chronic hyperinsulinemia due to insulin resistance and elevated levels of insulin-like growth factor (IGF)-1 and IGF-2 are suggestive of a significantly higher risk of endometrial carcinoma. There is a wealth of evidence showing differential expression of IGF-1 isoforms in various types of cancer. In the present study, 99 archived endometrial carcinoma tissue sections were retrospectively assessed by immunohistochemistry for IGF-1Ec isoform expression. Expression of IGF-1Ec was also assessed in nine cases of non-neoplastic endometrial tissue adjacent to the tumor, in 30 cases with normal endometrium and in 30 cases with endometrial hyperplasia. Furthermore, the association between IGF-1Ec and the concurrent expression of phosphatase and tensin homologue deleted on chromosome 10 (PTEN), p53 or survivin was assessed, as well as their combined expression in association with clinicopathological variables. In endometrial carcinoma, IGF-1Ec expression was high in non-endometrioid carcinoma (serous papillary or clear cell carcinoma) compared with that in endometrioid adenocarcinoma. IGF-1Ec expression was also high in the presence of tumoral necrosis. Furthermore, there was a significant correlation between the histological differentiation and the sum of staining intensity and the number of IGF-1Ec immunopositive cells in endometrial carcinoma. There was a moderate negative correlation between co-expression of IGF-1Ec and PTEN, for both the number of immunopositive cells (P=0.006, ρ=−0.343) and the sum of staining (scores and intensity; P=0.006, ρ=−0.343). Furthermore, there was a positive correlation between the sum of staining (scores and intensity) and co-expression of IGF-1Ec and survivin (P=0.043, ρ=0.225). However, there was no association between concomitant expression of IGF-1Ec and p53. These results emphasized the importance of IGF-1Ec expression during development of non-estrogen dependent endometrial adenocarcinoma. IGF-1Ec and PTEN may function opposingly during endometrial carcinogenesis. By contrast, IGF-1Ec and survivin may share common molecular pathways and may promote, in parallel, tumoral development.
Collapse
Affiliation(s)
- Aggelis Stavropoulos
- Fourth Obstetrics and Gynecology Department, 'Elena Venizelou' General Hospital, Athens 11521, Greece
| | - Michail Varras
- Fifth Obstetrics and Gynecology Department, 'Elena Venizelou' General Hospital, Athens 11521, Greece
| | - Anastassios Philippou
- Department of Physiology, Medical School, National Kapodistrian University, Athens 11527, Greece
| | - Thivi Vasilakaki
- Pathology Department, 'Tzaneio' General Hospital, Piraeus 18536, Greece
| | | | - Fani-Niki Varra
- Pharmacy Department, Frederick University, Nicosia 1036, Cyprus
| | | | - Andreas C Lazaris
- First Pathology Department, Medical School, National Kapodistrian University, Athens 11527, Greece
| | - Michael Koutsilieris
- Department of Physiology, Medical School, National Kapodistrian University, Athens 11527, Greece
| |
Collapse
|
4
|
Role of Alternatively Spliced Messenger RNA (mRNA) Isoforms of the Insulin-Like Growth Factor 1 (IGF1) in Selected Human Tumors. Int J Mol Sci 2020; 21:ijms21196995. [PMID: 32977489 PMCID: PMC7582825 DOI: 10.3390/ijms21196995] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 09/20/2020] [Accepted: 09/21/2020] [Indexed: 02/07/2023] Open
Abstract
Insulin-like growth factor 1 (IGF1) is a key regulator of tissue growth and development that is also implicated in the initiation and progression of various cancers. The human IGF1 gene contains six exons and five long introns, the transcription of which is controlled by two promoters (P1 and P2). Alternate promoter usage, as well as alternative splicing (AS) of IGF1, results in the expression of six various variants (isoforms) of mRNA, i.e., IA, IB, IC, IIA, IIB, and IIC. A mature 70-kDa IGF1 protein is coded only by exons 3 and 4, while exons 5 and 6 are alternatively spliced code for the three C-terminal E peptides: Ea (exon 6), Eb (exon 5), and Ec (fragments of exons 5 and 6). The most abundant of those transcripts is IGF1Ea, followed by IGF1Eb and IGF1Ec (also known as mechano-growth factor, MGF). The presence of different IGF1 transcripts suggests tissue-specific auto- and/or paracrine action, as well as separate regulation of both of these gene promoters. In physiology, the role of different IGF1 mRNA isoforms and pro-peptides is best recognized in skeletal muscle tissue. Their functions include the development and regeneration of muscles, as well as maintenance of proper muscle mass. In turn, in nervous tissue, a neuroprotective function of short peptides, produced as a result of IGF1 expression and characterized by significant blood-brain barrier penetrance, has been described and could be a potential therapeutic target. When it comes to the regulation of carcinogenesis, the potential biological role of different var iants of IGF1 mRNAs and pro-peptides is also intensively studied. This review highlights the role of IGF1 isoform expression (mRNAs, proteins) in physiology and different types of human tumors (e.g., breast cancer, cervical cancer, colorectal cancer, osteosarcoma, prostate and thyroid cancers), as well as mechanisms of IGF1 spliced variants involvement in tumor biology.
Collapse
|
5
|
Podratz JL, Tang JJ, Polzin MJ, Schmeichel AM, Nesbitt JJ, Windebank AJ, Madigan NN. Mechano growth factor interacts with nucleolin to protect against cisplatin-induced neurotoxicity. Exp Neurol 2020; 331:113376. [PMID: 32511954 DOI: 10.1016/j.expneurol.2020.113376] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 05/11/2020] [Accepted: 06/01/2020] [Indexed: 01/01/2023]
Abstract
Mechano growth factor (MGF) is an alternatively spliced form of insulin-like growth factor-1 (IGF-1) that has shown to be neuroprotective against 6-hydroxydopamine toxicity and ischemic injury in the brain. MGF also induces neural stem cell proliferation in the hippocampus and preserves olfactory function in aging mice. Cisplatin is a chemotherapy drug that induces peripheral neuropathy in 30-40% of treated patients. Our studies were designed to see if MGF would protect dorsal root ganglion (DRG) neurons from cisplatin-induced neurotoxicity and to identify potential mechanisms that may be involved. Expression of endogenous MGF in adult DRG neurons in vivo ameliorated cisplatin-induced thermal hyperalgesia. Exogenous MGF and MGF with a cysteine added to the N-terminus (CMGF) also protected embryonic DRG neurons from cisplatin-induced cell death in vitro. Mass spectroscopy analysis of proteins bound to MGF showed that nucleolin is a key-binding partner. Antibodies against nucleolin prevented the neuroprotective effect of MGF and CMGF in culture. Both nucleolin and MGF are located in the nucleolus of DRG neurons. RNAseq of RNA associated with MGF indicated that MGF may be involved in RNA processing, protein targeting and transcription/translation. Nucleolin is an RNA binding protein that is readily shuttled between the nucleus, cytoplasm and plasma membrane. Nucleolin and MGF may work together to prevent cisplatin-induced neurotoxicity. Exploring the known mechanisms of nucleolin may help us better understand the mechanisms of cisplatin toxicity and how MGF protects DRG neurons.
Collapse
Affiliation(s)
- J L Podratz
- Department of Neurology, Mayo Clinic, Rochester, MN, United States of America
| | - J J Tang
- Department of Neurology, Mayo Clinic, Rochester, MN, United States of America
| | - M J Polzin
- Department of Neurology, Mayo Clinic, Rochester, MN, United States of America
| | - A M Schmeichel
- Department of Neurology, Mayo Clinic, Rochester, MN, United States of America
| | - J J Nesbitt
- Department of Neurology, Mayo Clinic, Rochester, MN, United States of America
| | - A J Windebank
- Department of Neurology, Mayo Clinic, Rochester, MN, United States of America.
| | - N N Madigan
- Department of Neurology, Mayo Clinic, Rochester, MN, United States of America
| |
Collapse
|
6
|
Hernandez DM, Kang JH, Choudhury M, Andrianifahanana M, Yin X, Limper AH, Leof EB. IPF pathogenesis is dependent upon TGFβ induction of IGF-1. FASEB J 2020; 34:5363-5388. [PMID: 32067272 PMCID: PMC7136152 DOI: 10.1096/fj.201901719rr] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 02/03/2020] [Accepted: 02/05/2020] [Indexed: 12/13/2022]
Abstract
Pathogenic fibrotic diseases, including idiopathic pulmonary fibrosis (IPF), have some of the worst prognoses and affect millions of people worldwide. With unclear etiology and minimally effective therapies, two-thirds of IPF patients die within 2-5 years from this progressive interstitial lung disease. Transforming Growth Factor Beta (TGFβ) and insulin-like growth factor-1 (IGF-1) are known to promote fibrosis; however, myofibroblast specific upregulation of IGF-1 in the initiation and progression of TGFβ-induced fibrogenesis and IPF have remained unexplored. To address this, the current study (1) documents the upregulation of IGF-1 via TGFβ in myofibroblasts and fibrotic lung tissue, as well as its correlation with decreased pulmonary function in advanced IPF; (2) identifies IGF-1's C1 promoter as mediating the increase in IGF-1 transcription by TGFβ in pulmonary fibroblasts; (3) determines that SMAD2 and mTOR signaling are required for TGFβ-dependent Igf-1 expression in myofibroblasts; (4) demonstrates IGF-1R activation is essential to support TGFβ-driven profibrotic myofibroblast functions and excessive wound healing; and (5) establishes the effectiveness of slowing the progression of murine lung fibrosis with the IGF-1R inhibitor OSI-906. These findings expand our knowledge of IGF-1's role as a novel fibrotic-switch, bringing us one step closer to understanding the complex biological mechanisms responsible for fibrotic diseases and developing effective therapies.
Collapse
Affiliation(s)
- Danielle M. Hernandez
- Mayo Clinic Graduate School of Biomedical Sciences, Biochemistry & Molecular Biology Department, Mayo Clinic College of Medicine and Science, Rochester, MN 55905, USA
- Thoracic Disease Research Unit, Division of Pulmonary and Critical Care Medicine, Department of Medicine, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
- Current Address: Department of Neurosurgery, Masonic Cancer Center, University of Minnesota Twin Cities, Minneapolis, MN 55455, USA
| | - Jeong-Han Kang
- Thoracic Disease Research Unit, Division of Pulmonary and Critical Care Medicine, Department of Medicine, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
- Current Address: Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Malay Choudhury
- Thoracic Disease Research Unit, Division of Pulmonary and Critical Care Medicine, Department of Medicine, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Mahefatiana Andrianifahanana
- Thoracic Disease Research Unit, Division of Pulmonary and Critical Care Medicine, Department of Medicine, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Xueqian Yin
- Thoracic Disease Research Unit, Division of Pulmonary and Critical Care Medicine, Department of Medicine, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
- Current Address: Department of Molecular Medicine, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Andrew H. Limper
- Thoracic Disease Research Unit, Division of Pulmonary and Critical Care Medicine, Department of Medicine, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Edward B. Leof
- Thoracic Disease Research Unit, Division of Pulmonary and Critical Care Medicine, Department of Medicine, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| |
Collapse
|
7
|
Poreba E, Durzynska J. Nuclear localization and actions of the insulin-like growth factor 1 (IGF-1) system components: Transcriptional regulation and DNA damage response. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2020; 784:108307. [PMID: 32430099 DOI: 10.1016/j.mrrev.2020.108307] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 12/14/2022]
Abstract
Insulin-like growth factor (IGF) system stimulates growth, proliferation, and regulates differentiation of cells in a tissue-specific manner. It is composed of two insulin-like growth factors (IGF-1 and IGF-2), six insulin-like growth factor-binding proteins (IGFBPs), and two insulin-like growth factor receptors (IGF-1R and IGF-2R). IGF actions take place mostly through the activation of the plasma membrane-bound IGF-Rs by the circulating ligands (IGFs) released from the IGFBPs that stabilize their levels in the serum. This review focuses on the IGF-1 part of the system. The IGF-1 gene, which is expressed mainly in the liver as well as in other tissues, comprises six alternatively spliced exons that code for three protein isoforms (pro-IGF-1A, pro-IGF-1B, and pro-IGF-1C), which are processed to mature IGF-1 and E-peptides. The IGF-1R undergoes autophosphorylation, resulting in a signaling cascade involving numerous cytoplasmic proteins such as AKT and MAPKs, which regulate the expression of target genes. However, a more complex picture of the axis has recently emerged with all its components being translocated to the nuclear compartment. IGF-1R takes part in the regulation of gene expression by forming transcription complexes, modifying the activity of chromatin remodeling proteins, and participating in DNA damage tolerance mechanisms. Four IGFBPs contain a nuclear localization signal (NLS), which targets them to the nucleus, where they regulate gene expression (IGFBP-2, IGFBP-3, IGFBP-5, IGFBP-6) and DNA damage repair (IGFBP-3 and IGFBP-6). Last but not least, the IGF-1B isoform has been reported to be localized in the nuclear compartment. However, no specific molecular actions have been assigned to the nuclear pro-IGF-1B or its derivative EB peptide. Therefore, further studies are needed to shed light on their nuclear activity. These recently uncovered nuclear actions of different components of the IGF-1 axis are relevant in cancer cell biology and are discussed in this review.
Collapse
Affiliation(s)
- Elzbieta Poreba
- Institute of Experimental Biology, Faculty of Biology, Adam Mickiewicz University, ul. Uniwersytetu Poznańskiego 6, 61-614, Poznań, Poland.
| | - Julia Durzynska
- Institute of Experimental Biology, Faculty of Biology, Adam Mickiewicz University, ul. Uniwersytetu Poznańskiego 6, 61-614, Poznań, Poland.
| |
Collapse
|
8
|
Pharmacological Benefits and Risk of Using Hormones in Organ Perfusion and Preservation Solutions in the Aspect of Minimizing Hepatic Ischemia-Reperfusion Injury during Storage. BIOMED RESEARCH INTERNATIONAL 2019; 2019:6467134. [PMID: 31828112 PMCID: PMC6881579 DOI: 10.1155/2019/6467134] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/31/2019] [Accepted: 10/23/2019] [Indexed: 01/11/2023]
Abstract
For several years, research has been carried out on the effectiveness of solutions for perfusion and preservation of organs, including the liver. There is a search for an optimal pharmacological composition of these solutions, allowing to preserve or improve vital functions of the organ for as long as possible until it is transplanted into a recipient. Hormones due to their properties, often resulting from their pleiotropic effects, may be a valuable component for optimizing the composition of liver perfusion and preservation solutions. The paper presents the current state of knowledge on liver perfusion and preservation solutions modified with hormones. It also shows the characteristics of the hormones evaluated, taking into account their physiological functions in the body.
Collapse
|
9
|
Barton ER, Pham J, Brisson BK, Park S, Smith LR, Liu M, Tian Z, Hammers DW, Vassilakos G, Sweeney HL. Functional muscle hypertrophy by increased insulin-like growth factor 1 does not require dysferlin. Muscle Nerve 2019; 60:464-473. [PMID: 31323135 PMCID: PMC6771521 DOI: 10.1002/mus.26641] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 07/11/2019] [Accepted: 07/15/2019] [Indexed: 11/24/2022]
Abstract
INTRODUCTION Dysferlin loss-of-function mutations cause muscular dystrophy, accompanied by impaired membrane repair and muscle weakness. Growth promoting strategies including insulin-like growth factor 1 (IGF-1) could provide benefit but may cause strength loss or be ineffective. The objective of this study was to determine whether locally increased IGF-1 promotes functional muscle hypertrophy in dysferlin-null (Dysf-/- ) mice. METHODS Muscle-specific transgenic expression and postnatal viral delivery of Igf1 were used in Dysf-/- and control mice. Increased IGF-1 levels were confirmed by enzyme-linked immunosorbent assay. Testing for skeletal muscle mass and function was performed in male and female mice. RESULTS Muscle hypertrophy occurred in response to increased IGF-1 in mice with and without dysferlin. Male mice showed a more robust response compared with females. Increased IGF-1 did not cause loss of force per cross-sectional area in Dysf-/- muscles. DISCUSSION We conclude that increased local IGF-1 promotes functional hypertrophy when dysferlin is absent and reestablishes IGF-1 as a potential therapeutic for dysferlinopathies.
Collapse
Affiliation(s)
- Elisabeth R. Barton
- Anatomy and Cell Biology, School of Dental MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvania
- Applied Physiology and KinesiologyCollege of Health and Human Performance, University of FloridaGainesvilleFlorida
| | - Jennifer Pham
- Department of Physiology, Perleman School of Medicine, University of PennsylvaniaPhiladelphiaPennsylvania
| | - Becky K. Brisson
- Anatomy and Cell Biology, School of Dental MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvania
| | - SooHyun Park
- Anatomy and Cell Biology, School of Dental MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvania
| | - Lucas R. Smith
- Anatomy and Cell Biology, School of Dental MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvania
| | - Min Liu
- Department of Physiology, Perleman School of Medicine, University of PennsylvaniaPhiladelphiaPennsylvania
| | - Zuozhen Tian
- Anatomy and Cell Biology, School of Dental MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvania
| | - David W. Hammers
- Department of Pharmacology and Therapeutics, College of Medicine, University of FloridaGainesvilleFlorida
| | - Georgios Vassilakos
- Applied Physiology and KinesiologyCollege of Health and Human Performance, University of FloridaGainesvilleFlorida
| | - H. Lee Sweeney
- Department of Physiology, Perleman School of Medicine, University of PennsylvaniaPhiladelphiaPennsylvania
- Department of Pharmacology and Therapeutics, College of Medicine, University of FloridaGainesvilleFlorida
| |
Collapse
|
10
|
Vassilakos G, Barton ER. Insulin-Like Growth Factor I Regulation and Its Actions in Skeletal Muscle. Compr Physiol 2018; 9:413-438. [PMID: 30549022 DOI: 10.1002/cphy.c180010] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The insulin-like growth factor (IGF) pathway is essential for promoting growth and survival of virtually all tissues. It bears high homology to its related protein insulin, and as such, there is an interplay between these molecules with regard to their anabolic and metabolic functions. Skeletal muscle produces a significant proportion of IGF-1, and is highly responsive to its actions, including increased muscle mass and improved regenerative capacity. In this overview, the regulation of IGF-1 production, stability, and activity in skeletal muscle will be described. Second, the physiological significance of the forms of IGF-1 produced will be discussed. Last, the interaction of IGF-1 with other pathways will be addressed. © 2019 American Physiological Society. Compr Physiol 9:413-438, 2019.
Collapse
Affiliation(s)
- Georgios Vassilakos
- Department of Applied Physiology and Kinesiology, College of Health and Human Performance, University of Florida, Gainesville, Florida, USA
| | - Elisabeth R Barton
- Department of Applied Physiology and Kinesiology, College of Health and Human Performance, University of Florida, Gainesville, Florida, USA
| |
Collapse
|
11
|
Sun KT, Cheung KK, Au SWN, Yeung SS, Yeung EW. Overexpression of Mechano-Growth Factor Modulates Inflammatory Cytokine Expression and Macrophage Resolution in Skeletal Muscle Injury. Front Physiol 2018; 9:999. [PMID: 30140235 PMCID: PMC6094977 DOI: 10.3389/fphys.2018.00999] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 07/09/2018] [Indexed: 11/13/2022] Open
Abstract
In muscle regeneration, infiltrating myeloid cells, such as macrophages mediate muscle inflammation by releasing key soluble factors. One such factor, insulin-like growth factor 1 (IGF-1), suppresses inflammatory cytokine expression and mediates macrophage polarization to anti-inflammatory phenotype during muscle injury. Previously the IGF-1Ea isoform was shown to be anti-inflammatory. Another isoform of IGF-1, mechano-growth factor (MGF), is structurally and functionally distinct from IGF-1Ea, but its role in muscle inflammation has not yet been characterized. In this study, we hypothesized that MGF expression in muscle injury modulates muscle inflammation. We first investigated changes of transcription and expression of MGF in response to skeletal muscle injury induced by cardiotoxin (CTX) in vivo. At 1–2 days post-injury, Mgf expression was significantly upregulated and positively correlated with that of inflammatory cytokines. Immunostaining revealed that infiltration of neutrophils and macrophages coincided with Mgf upregulation. Furthermore, infiltrating neutrophils and macrophages expressed Mgf, suggesting their contribution to MGF upregulation in muscle injury. Macrophages seem to be the predominant source of MGF in muscle injury, whereas neutrophil depletion did not affect muscle Mgf expression. Given the association of MGF and macrophages, we then studied whether MGF could affect macrophage infiltration and polarization. To test this, we overexpressed MGF in CTX-injured muscles and evaluated inflammatory marker expression, macrophage populations, and muscle regeneration outcomes. MGF overexpression delayed the resolution of macrophages, particularly the pro-inflammatory phenotype. This coincided with upregulation of inflammatory markers. Annexin V-based flow cytometry revealed that MGF overexpression likely delays macrophage resolution by limiting macrophage apoptosis. Although MGF overexpression did not obviously affect muscle regeneration outcomes, the findings are novel and provide insights on the physiological roles of MGF in muscle regeneration.
Collapse
Affiliation(s)
- Keng-Ting Sun
- Muscle Physiology Laboratory, Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Kowloon, Hong Kong
| | - Kwok-Kuen Cheung
- Muscle Physiology Laboratory, Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Kowloon, Hong Kong
| | - Shannon W N Au
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Simon S Yeung
- Muscle Physiology Laboratory, Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Kowloon, Hong Kong
| | - Ella W Yeung
- Muscle Physiology Laboratory, Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Kowloon, Hong Kong
| |
Collapse
|
12
|
Tang JJ, Podratz JL, Lange M, Scrable HJ, Jang MH, Windebank AJ. Mechano growth factor, a splice variant of IGF-1, promotes neurogenesis in the aging mouse brain. Mol Brain 2017; 10:23. [PMID: 28683812 PMCID: PMC5501366 DOI: 10.1186/s13041-017-0304-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 06/05/2017] [Indexed: 11/10/2022] Open
Abstract
Mechano growth factor (MGF) is a splice variant of IGF-1 first described in skeletal muscle. MGF induces muscle cell proliferation in response to muscle stress and injury. In control mice we found endogenous expression of MGF in neurogenic areas of the brain and these levels declined with age. To better understand the role of MGF in the brain, we used transgenic mice that constitutively overexpressed MGF from birth. MGF overexpression significantly increased the number of BrdU+ proliferative cells in the dentate gyrus (DG) of the hippocampus and subventricular zone (SVG). Although MGF overexpression increased the overall rate of adult hippocampal neurogenesis at the proliferation stage it did not alter the distribution of neurons at post-mitotic maturation stages. We then used the lac-operon system to conditionally overexpress MGF in the mouse brain beginning at 1, 3 and 12 months with histological and behavioral observation at 24 months of age. With conditional overexpression there was an increase of BrdU+ proliferating cells and BrdU+ differentiated mature neurons in the olfactory bulbs at 24 months when overexpression was induced from 1 and 3 months of age but not when started at 12 months. This was associated with preserved olfactory function. In vitro, MGF increased the size and number of neurospheres harvested from SVZ-derived neural stem cells (NSCs). These findings indicate that MGF overexpression increases the number of neural progenitor cells and promotes neurogenesis but does not alter the distribution of adult newborn neurons at post-mitotic stages. Maintaining youthful levels of MGF may be important in reversing age-related neuronal loss and brain dysfunction.
Collapse
Affiliation(s)
- Jason J Tang
- Department of Neurology, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN, 55905, USA
| | - Jewel L Podratz
- Department of Neurology, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN, 55905, USA
| | - Miranda Lange
- Department of Neurology, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN, 55905, USA
| | - Heidi J Scrable
- Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, MN, USA.,The Kogod Center on Aging, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Mi-Hyeon Jang
- Department of Neurologic Surgery, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Anthony J Windebank
- Department of Neurology, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN, 55905, USA.
| |
Collapse
|
13
|
Vassilakos G, Philippou A, Koutsilieris M. Identification of the IGF-1 processing product human Ec/rodent Eb peptide in various tissues: Evidence for its differential regulation after exercise-induced muscle damage in humans. Growth Horm IGF Res 2017; 32:22-28. [PMID: 27836414 DOI: 10.1016/j.ghir.2016.11.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 08/16/2016] [Accepted: 11/02/2016] [Indexed: 10/20/2022]
Abstract
OBJECTIVE Insulin-like growth factor-1 (IGF-1) is a pleiotropic factor expressed in various tissues and plays a critical role in skeletal muscle physiology. Alternative splicing of the IGF-1 gene gives rise to different precursor polypeptides (isoforms) which could undergo post-translational cleavage, generating the common mature IGF-1 peptide and different carboxyl terminal extension (E-) peptides, with the fate of the latter being, so far, unknown. The objective if this study was to identify the IGF-1Ec forms or processing product(s), other than mature IGF-1, generated in different human and rodent tissues and particularly in human skeletal muscle after exercise-induced damage. DESIGN Protein lysates from a wide range of human and rodent tissues were immunoblotted with a rabbit anti-human Ec polyclonal antibody raised against the last 24 amino acids of the C-terminal of the Ec peptide. This antibody can recognize the Ec peptide, both as part of IGF-1Ec and alone, and also the corresponding rodent forms, due to the high homology that the human Ec shares with the rodent Eb. RESULTS We were able to confirm, for the first time, that the human Ec peptide and its rodent homologous Eb peptide are produced simultaneously with their precursor protein (pro-IGF-1Ec/Eb) in vivo, in a wide range of tissues (e.g. muscle, liver, heart). Proprotein convertase furin digestion of human muscle and liver protein lysates confirmed that the higher molecular form, pro-IGF-1Ec, can be cleaved to produce the free Ec peptide. Furthermore, initial evidence is provided that Ec peptide is differentially regulated during the process of muscle regeneration after exercise-induced damage in humans. CONCLUSIONS The findings of this study possibly imply that the post-translational modification of the IGF-1Ec pro-peptide may regulate the bioavailability and activity of the processing product(s).
Collapse
Affiliation(s)
- George Vassilakos
- Department of Experimental Physiology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Anastassios Philippou
- Department of Experimental Physiology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Michael Koutsilieris
- Department of Experimental Physiology, Medical School, National and Kapodistrian University of Athens, Athens, Greece.
| |
Collapse
|
14
|
Chen H, Lv K, Dai Z, Ji G, Wang T, Wang Y, Zhang Y, Kan G, Li Y, Qu L. Intramuscular injection of mechano growth factor E domain peptide regulated expression of memory-related sod, miR-134 and miR-125b-3p in rat hippocampus under simulated weightlessness. Biotechnol Lett 2016; 38:2071-2080. [PMID: 27623796 DOI: 10.1007/s10529-016-2210-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 08/31/2016] [Indexed: 01/22/2023]
Abstract
OBJECTIVE To investigate the expression of memory-related antioxidant genes and miRNAs under simulated weightlessness and the regulation of mechano growth factor (MGF) E domain, the peptide preventing nerve damage. RESULTS Igf-iea and mgf mRNA levels, expression of antioxidant genes sod1 and sod2 and levels of miR-134 and miR-125b-3p increased in rat hippocampus after 14 days tail suspension to simulate weightlessness which was inhibited with intramuscular injection of E domain peptide. Therefore, administration of MGF E domain peptide could reverse increased expressions of memory-related igf-iea, mgf, sod1, sod2, miR-134 and miR-125b-3p in rat hippocampus under simulated weightlessness. CONCLUSIONS MGF may regulate the redox state and miRNA-targeted NR-CREB signaling, and intramuscular injection may be the alternative administration because of its safety, convenience and ability to pass through the blood brain barrier.
Collapse
Affiliation(s)
- Hailong Chen
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, 5132-23#, Beiqing Road 26#, Haidian District, Beijing, 100094, China.,Department of Health Technology Research and Development, Space Institute of Southern China (Shenzhen), Shamiao Road 4#, Pingdi Street, Longgang District, Shenzhen, 518117, China
| | - Ke Lv
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, 5132-23#, Beiqing Road 26#, Haidian District, Beijing, 100094, China
| | - Zhongquan Dai
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, 5132-23#, Beiqing Road 26#, Haidian District, Beijing, 100094, China
| | - Guohua Ji
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, 5132-23#, Beiqing Road 26#, Haidian District, Beijing, 100094, China
| | - Tingmei Wang
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, 5132-23#, Beiqing Road 26#, Haidian District, Beijing, 100094, China
| | - Yanli Wang
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, 5132-23#, Beiqing Road 26#, Haidian District, Beijing, 100094, China
| | - Yongliang Zhang
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, 5132-23#, Beiqing Road 26#, Haidian District, Beijing, 100094, China
| | - Guanghan Kan
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, 5132-23#, Beiqing Road 26#, Haidian District, Beijing, 100094, China
| | - Yinghui Li
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, 5132-23#, Beiqing Road 26#, Haidian District, Beijing, 100094, China.
| | - Lina Qu
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, 5132-23#, Beiqing Road 26#, Haidian District, Beijing, 100094, China.
| |
Collapse
|