1
|
Orgil BO, Purevjav E. Molecular Pathways and Animal Models of Cardiomyopathies. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1441:991-1019. [PMID: 38884766 DOI: 10.1007/978-3-031-44087-8_64] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2024]
Abstract
Cardiomyopathies are a heterogeneous group of disorders of the heart muscle that ultimately result in congestive heart failure. Rapid progress in genetics, molecular and cellular biology with breakthrough innovative genetic-engineering techniques, such as next-generation sequencing and multiomics platforms, stem cell reprogramming, as well as novel groundbreaking gene-editing systems over the past 25 years has greatly improved the understanding of pathogenic signaling pathways in inherited cardiomyopathies. This chapter will focus on intracellular and intercellular molecular signaling pathways that are activated by a genetic insult in cardiomyocytes to maintain tissue and organ level regulation and resultant cardiac remodeling in certain forms of cardiomyopathies. In addition, animal models of different clinical forms of human cardiomyopathies with their summaries of triggered key molecules and signaling pathways will be described.
Collapse
Affiliation(s)
- Buyan-Ochir Orgil
- Department of Pediatrics, The Heart Institute, Division of Cardiology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Enkhsaikhan Purevjav
- Department of Pediatrics, The Heart Institute, Division of Cardiology, University of Tennessee Health Science Center, Memphis, TN, USA.
| |
Collapse
|
2
|
Erdman VV, Karimov DD, Tuktarova IA, Timasheva YR, Nasibullin TR, Korytina GF. Alu Deletions in LAMA2 and CDH4 Genes Are Key Components of Polygenic Predictors of Longevity. Int J Mol Sci 2022; 23:13492. [PMID: 36362280 PMCID: PMC9657309 DOI: 10.3390/ijms232113492] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 10/27/2022] [Accepted: 10/31/2022] [Indexed: 10/18/2023] Open
Abstract
Longevity is a unique human phenomenon and a highly stable trait, characterized by polygenicity. The longevity phenotype occurs due to the ability to successfully withstand the age-related genomic instability triggered by Alu elements. The purpose of our cross-sectional study was to evaluate the combined contribution of ACE*Ya5ACE, CDH4*Yb8NBC516, COL13A1*Ya5ac1986, HECW1*Ya5NBC182, LAMA2*Ya5-MLS19, PLAT*TPA25, PKHD1L1*Yb8AC702, SEMA6A*Yb8NBC597, STK38L*Ya5ac2145 and TEAD1*Ya5ac2013 Alu elements to longevity. The study group included 2054 unrelated individuals aged from 18 to 113 years who are ethnic Tatars from Russia. We analyzed the dynamics of the allele and genotype frequencies of the studied Alu polymorphic loci in the age groups of young (18-44 years old), middle-aged (45-59 years old), elderly (60-74 years old), old seniors (75-89 years old) and long-livers (90-113 years old). Most significant changes in allele and genotype frequencies were observed between the long-livers and other groups. The search for polygenic predictors of longevity was performed using the APSampler program. Attaining longevity was associated with the combinations LAMA2*ID + CDH4*D (OR = 2.23, PBonf = 1.90 × 10-2) and CDH4*DD + LAMA2*ID + HECW1*D (OR = 4.58, PBonf = 9.00 × 10-3) among persons aged between 18 and 89 years, LAMA2*ID + CDH4*D + SEMA6A*I for individuals below 75 years of age (OR = 3.13, PBonf = 2.00 × 10-2), LAMA2*ID + HECW1*I for elderly people aged 60 and older (OR = 3.13, PBonf = 2.00 × 10-2) and CDH4*DD + LAMA2*D + HECW1*D (OR = 4.21, PBonf = 2.60 × 10-2) and CDH4*DD + LAMA2*D + ACE*I (OR = 3.68, PBonf = 1.90 × 10-2) among old seniors (75-89 years old). The key elements of combinations associated with longevity were the deletion alleles of CDH4 and LAMA2 genes. Our results point to the significance for human longevity of the Alu polymorphic loci in CDH4, LAMA2, HECW1, SEMA6A and ACE genes, involved in the integration systems.
Collapse
Affiliation(s)
- Vera V. Erdman
- Institute of Biochemistry and Genetics, Subdivision of the Ufa Federal Research Centre of the Russian Academy of Sciences, 450054 Ufa, Russia
| | - Denis D. Karimov
- Ufa Research Institute of Labor Medicine and Human Ecology, 450106 Ufa, Russia
| | - Ilsia A. Tuktarova
- Institute of Biochemistry and Genetics, Subdivision of the Ufa Federal Research Centre of the Russian Academy of Sciences, 450054 Ufa, Russia
| | - Yanina R. Timasheva
- Institute of Biochemistry and Genetics, Subdivision of the Ufa Federal Research Centre of the Russian Academy of Sciences, 450054 Ufa, Russia
| | - Timur R. Nasibullin
- Institute of Biochemistry and Genetics, Subdivision of the Ufa Federal Research Centre of the Russian Academy of Sciences, 450054 Ufa, Russia
| | - Gulnaz F. Korytina
- Institute of Biochemistry and Genetics, Subdivision of the Ufa Federal Research Centre of the Russian Academy of Sciences, 450054 Ufa, Russia
| |
Collapse
|
3
|
Fabian L, Dowling JJ. Zebrafish Models of LAMA2-Related Congenital Muscular Dystrophy (MDC1A). Front Mol Neurosci 2020; 13:122. [PMID: 32742259 PMCID: PMC7364686 DOI: 10.3389/fnmol.2020.00122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 06/11/2020] [Indexed: 01/28/2023] Open
Abstract
LAMA2-related congenital muscular dystrophy (CMD; LAMA2-MD), also referred to as merosin deficient CMD (MDC1A), is a severe neonatal onset muscle disease caused by recessive mutations in the LAMA2 gene. LAMA2 encodes laminin α2, a subunit of the extracellular matrix (ECM) oligomer laminin 211. There are currently no treatments for MDC1A, and there is an incomplete understanding of disease pathogenesis. Zebrafish, due to their high degree of genetic conservation with humans, large clutch sizes, rapid development, and optical clarity, have emerged as an excellent model system for studying rare Mendelian diseases. They are particularly suitable as a model for muscular dystrophy because they contain at least one orthologue to all major human MD genes, have muscle that is similar to human muscle in structure and function, and manifest obvious and easily measured MD related phenotypes. In this review article, we present the existing zebrafish models of MDC1A, and discuss their contribution to the understanding of MDC1A pathomechanisms and therapy development.
Collapse
Affiliation(s)
- Lacramioara Fabian
- Program for Genetics and Genome Biology, Hospital for Sick Children, Toronto, ON, Canada
| | - James J Dowling
- Program for Genetics and Genome Biology, Hospital for Sick Children, Toronto, ON, Canada.,Division of Neurology, Hospital for Sick Children, Toronto, ON, Canada.,Departments of Pediatrics and Molecular Genetics, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
4
|
Disabled-2: a positive regulator of the early differentiation of myoblasts. Cell Tissue Res 2020; 381:493-508. [PMID: 32607799 PMCID: PMC7431403 DOI: 10.1007/s00441-020-03237-2] [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: 01/21/2020] [Accepted: 06/05/2020] [Indexed: 11/25/2022]
Abstract
Dab2 is an adaptor protein and a tumor suppressor. Our previous study has found that Dab2 was expressed in early differentiating skeletal muscles in mouse embryos. In this study, we determined the role of Dab2 in the skeletal muscle differentiation using C2C12 myoblasts in vitro and Xenopus laevis embryos in vivo. The expression of Dab2 was increased in C2C12 myoblasts during the formation of myotubes in vitro. Knockdown of Dab2 expression in C2C12 myoblasts resulted in a reduction of myotube formation, whereas the myotube formation was enhanced upon overexpression of Dab2. Re-expression of Dab2 in C2C12 myoblasts with downregulated expression of Dab2 restored their capacity to form myotubes. Microarray profiling and subsequent network analyses on the 155 differentially expressed genes after Dab2 knockdown showed that Mef2c was an important myogenic transcription factor regulated by Dab2 through the p38 MAPK pathway. It was also involved in other pathways that are associated with muscular development and functions. In Xenopus embryos developed in vivo, XDab2 was expressed in the myotome of somites where various myogenic markers were also expressed. Knockdown of XDab2 expression with antisense morpholinos downregulated the expression of myogenic markers in somites. In conclusion, this study is the first to provide solid evidence to show that Dab2 is a positive regulator of the early myoblast differentiation.
Collapse
|
5
|
Yamamoto-Shimojima K, Ono H, Imaizumi T, Yamamoto T. Novel LAMA2 variants identified in a patient with white matter abnormalities. Hum Genome Var 2020; 7:16. [PMID: 32509318 PMCID: PMC7248065 DOI: 10.1038/s41439-020-0103-5] [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: 03/01/2020] [Revised: 04/23/2020] [Accepted: 04/24/2020] [Indexed: 11/24/2022] Open
Abstract
Comprehensive genomic analysis was performed in a patient with mild psychomotor developmental delay, elevated creatine kinase, and white matter abnormalities. The results revealed biallelic pathogenic variants in the gene related to merosin-deficient congenital muscular dystrophy, NM_000426.3(LAMA2):c.1338_1339del [p.Gly447Phefs*7] and c.2749 + 2dup, which consist of compound heterozygous involvement with predicted loss-of-function and splicing abnormalities.
Collapse
Affiliation(s)
- Keiko Yamamoto-Shimojima
- Japan Society for the Promotion of Science (RPD), Tokyo, Japan
- Institute of Medical Genetics, Tokyo Women’s Medical University, Tokyo, Japan
- Tokyo Women’s Medical University Institute for Integrated Medical Sciences, Tokyo, Japan
| | - Hiroaki Ono
- Department of Pediatrics, Hiroshima Prefectural Hospital, Hiroshima, Japan
| | - Taichi Imaizumi
- Institute of Medical Genetics, Tokyo Women’s Medical University, Tokyo, Japan
- Department of Pediatrics, St. Marianna University School of Medicine, Kawasaki, Japan
| | - Toshiyuki Yamamoto
- Institute of Medical Genetics, Tokyo Women’s Medical University, Tokyo, Japan
- Tokyo Women’s Medical University Institute for Integrated Medical Sciences, Tokyo, Japan
- Department of Pediatrics, St. Marianna University School of Medicine, Kawasaki, Japan
| |
Collapse
|
6
|
Heikkinen A, Härönen H, Norman O, Pihlajaniemi T. Collagen XIII and Other ECM Components in the Assembly and Disease of the Neuromuscular Junction. Anat Rec (Hoboken) 2019; 303:1653-1663. [PMID: 30768864 DOI: 10.1002/ar.24092] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 08/17/2018] [Accepted: 09/27/2018] [Indexed: 12/15/2022]
Abstract
Alongside playing structural roles, the extracellular matrix (ECM) acts as an interaction platform for cellular homeostasis, organ development, and maintenance. The necessity of the ECM is highlighted by the diverse, sometimes very serious diseases that stem from defects in its components. The neuromuscular junction (NMJ) is a large peripheral motor synapse differing from its central counterparts through the ECM included at the synaptic cleft. Such synaptic basal lamina (BL) is specialized to support NMJ establishment, differentiation, maturation, stabilization, and function and diverges in molecular composition from the extrasynaptic ECM. Mutations, toxins, and autoantibodies may compromise NMJ integrity and function, thereby leading to congenital myasthenic syndromes (CMSs), poisoning, and autoimmune diseases, respectively, and all these conditions may involve synaptic ECM molecules. With neurotransmission degraded or blocked, muscle function is impaired or even prevented. At worst, this can be fatal. The article reviews the synaptic BL composition required for assembly and function of the NMJ molecular machinery through the lens of studies primarily with mouse models but also with human patients. In-depth focus is given to collagen XIII, a postsynaptic-membrane-spanning but also shed ECM protein that in recent years has been revealed to be a significant component for the NMJ. Its deficiency in humans causes CMS, and autoantibodies against it have been recognized in autoimmune myasthenia gravis. Mouse models have exposed numerous details that appear to recapitulate human NMJ phenotypes relatively faithfully and thereby can be readily used to generate information necessary for understanding and ultimately treating human diseases. Anat Rec, 2019. © 2019 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Anne Heikkinen
- Oulu Center for Cell-Matrix Research, Biocenter Oulu, Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Heli Härönen
- Oulu Center for Cell-Matrix Research, Biocenter Oulu, Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Oula Norman
- Oulu Center for Cell-Matrix Research, Biocenter Oulu, Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Taina Pihlajaniemi
- Oulu Center for Cell-Matrix Research, Biocenter Oulu, Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| |
Collapse
|
7
|
Yoon S, Beermann ML, Yu B, Shao D, Bachschmid M, Miller JB. Aberrant Caspase Activation in Laminin-α2-Deficient Human Myogenic Cells is Mediated by p53 and Sirtuin Activity. J Neuromuscul Dis 2018; 5:59-73. [PMID: 29278895 PMCID: PMC5836413 DOI: 10.3233/jnd-170262] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Background: Mutations in the LAMA2 gene encoding laminin-α2 cause congenital muscular dystrophy Type 1A (MDC1A), a severe recessive disease with no effective treatment. Previous studies have shown that aberrant activation of caspases and cell death through a pathway regulated by BAX and KU70 is a significant contributor to pathogenesis in laminin-α2-deficiency. Objectives: To identify mechanisms of pathogenesis in MDC1A. Methods: We used immunocytochemical and molecular studies of human myogenic cells and mouse muscles—comparing laminin-α2-deficient vs. healthy controls—to identify mechanisms that regulate pathological activation of caspase in laminin-α2-deficiency. Results: In cultures of myogenic cells from MDC1A donors, p53 accumulated in a subset of nuclei and aberrant caspase activation was inhibited by the p53 inhibitor pifithrin-alpha. Also, the p53 target BBC3 (PUMA) was upregulated in both MDC1A myogenic cells and Lama2–/– mouse muscles. In addition, studies with sirtuin inhibitors and SIRT1 overexpression showed that caspase activation in MDC1A myotubes was inversely related to sirtuin deacetylase activity. Caspase activation in laminin-α2-deficiency was, however, not associated with increased phosphorylation of p38 MAPK. Conclusions: Aberrant caspase activation in MDC1A cells was mediated both by sirtuin deacetylase activity and by p53. Interventions that inhibit aberrant caspase activation by targeting sirtuin or p53 function could potentially be useful in ameliorating MDC1A.
Collapse
Affiliation(s)
- Soonsang Yoon
- Department of Neurology, Boston University School of Medicine, Boston, MA, USA
| | - Mary Lou Beermann
- Department of Neurology, Boston University School of Medicine, Boston, MA, USA
| | - Bryant Yu
- Department of Neurology, Boston University School of Medicine, Boston, MA, USA
| | - Di Shao
- Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA, USA
| | - Markus Bachschmid
- Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA, USA
| | | |
Collapse
|
8
|
Zhou J, Tan J, Ma D, Zhang J, Cheng J, Luo C, Liu G, Wang Y, Xu Z. Identification of Two Novel LAMA2 Mutations in a Chinese Patient with Congenital Muscular Dystrophy. Front Genet 2018; 9:43. [PMID: 29487616 PMCID: PMC5816747 DOI: 10.3389/fgene.2018.00043] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2017] [Accepted: 01/30/2018] [Indexed: 01/06/2023] Open
Abstract
Merosin-deficient CMD type 1A (MDC1A), caused by mutations of laminin subunit alpha 2 (LAMA2), is a predominant subtype of congenital muscular dystrophy (CMD). Herein, we described a Chinese patient with MDC1A who was admitted to hospital 17 days after birth because of marasmus and feeding difficulties. Mutations were identified by targeted capture and next generation sequencing (NGS) and further confirmed by Sanger sequencing. Paternity was confirmed by short tandem repeat analysis. Physical examination showed malnutrition, poor suck and appendicular hypotonia. Her serum CK levels were 2483 and 1962 U/L at 2 and 4 months of age, respectively. Brain magnetic resonance imaging performed at 1 month of age presented hyperintensity on T2-weighted images, T1-weighted images in parietal and occipital lobes, and diffusion-weighted image (DWI) as well as hypointensity on fluid attenuated inversion recovery (FLAIR) image; however, the cerebellum and corpus arenaceum were normal. At 7 months of age, delayed developmental milestones were observed, and she failed to turn her body over and raise her head up. A point mutation (c.1782+2T > G) and a frameshift duplication (c.8217dupT) in the LAMA2 gene were identified by targeted capture and NGS and further confirmed by Sanger sequencing. Moreover, genotyping with multiple short tandem repeat markers confirmed paternity to demonstrate that the point mutation is de novo. The frameshift duplication (c.8217dupT), inherited from her mother, was predicted to cause a substitution of Pro (P) to Ser (S) at the 2740th amino-acid residue and generate a prematurely truncated protein. The in silico analysis suggests that the mutation (c.1782+2T > G) may lead to aberrant splicing of LAMA2. Our case further confirms the heterogeneous clinical spectrum of MDC1A and presents two novel LAMA2 mutations to expand the mutation spectrum of MDC1A.
Collapse
Affiliation(s)
- Jing Zhou
- Department of Prenatal Diagnosis, State Key Laboratory of Reproductive Medicine, The Affiliated Obstetrics and Gynecology Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Jianxin Tan
- Department of Prenatal Diagnosis, State Key Laboratory of Reproductive Medicine, The Affiliated Obstetrics and Gynecology Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Dingyuan Ma
- Department of Prenatal Diagnosis, State Key Laboratory of Reproductive Medicine, The Affiliated Obstetrics and Gynecology Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Jingjing Zhang
- Department of Prenatal Diagnosis, State Key Laboratory of Reproductive Medicine, The Affiliated Obstetrics and Gynecology Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Jian Cheng
- Department of Prenatal Diagnosis, State Key Laboratory of Reproductive Medicine, The Affiliated Obstetrics and Gynecology Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Chunyu Luo
- Department of Prenatal Diagnosis, State Key Laboratory of Reproductive Medicine, The Affiliated Obstetrics and Gynecology Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Gang Liu
- Department of Prenatal Diagnosis, State Key Laboratory of Reproductive Medicine, The Affiliated Obstetrics and Gynecology Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Yuguo Wang
- Department of Prenatal Diagnosis, State Key Laboratory of Reproductive Medicine, The Affiliated Obstetrics and Gynecology Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Zhengfeng Xu
- Department of Prenatal Diagnosis, State Key Laboratory of Reproductive Medicine, The Affiliated Obstetrics and Gynecology Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| |
Collapse
|
9
|
Smith LR, Barton ER. Regulation of fibrosis in muscular dystrophy. Matrix Biol 2018; 68-69:602-615. [PMID: 29408413 DOI: 10.1016/j.matbio.2018.01.014] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 01/15/2018] [Accepted: 01/16/2018] [Indexed: 02/08/2023]
Abstract
The production of force and power are inherent properties of skeletal muscle, and regulated by contractile proteins within muscle fibers. However, skeletal muscle integrity and function also require strong connections between muscle fibers and their extracellular matrix (ECM). A well-organized and pliant ECM is integral to muscle function and the ability for many different cell populations to efficiently migrate through ECM is critical during growth and regeneration. For many neuromuscular diseases, genetic mutations cause disruption of these cytoskeletal-ECM connections, resulting in muscle fragility and chronic injury. Ultimately, these changes shift the balance from myogenic pathways toward fibrogenic pathways, culminating in the loss of muscle fibers and their replacement with fatty-fibrotic matrix. Hence a common pathological hallmark of muscular dystrophy is prominent fibrosis. This review will cover the salient features of muscular dystrophy pathogenesis, highlight the signals and cells that are important for myogenic and fibrogenic actions, and discuss how fibrosis alters the ECM of skeletal muscle, and the consequences of fibrosis in developing therapies.
Collapse
Affiliation(s)
- Lucas R Smith
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, PA, United States
| | - Elisabeth R Barton
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, United States.
| |
Collapse
|
10
|
Development Aspects of Zebrafish Myotendinous Junction: a Model System for Understanding Muscle Basement Membrane Formation and Failure. CURRENT PATHOBIOLOGY REPORTS 2017. [DOI: 10.1007/s40139-017-0140-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|
11
|
Gao Y, Chen H, Lui WY, Lee WM, Cheng CY. Basement Membrane Laminin α2 Regulation of BTB Dynamics via Its Effects on F-Actin and Microtubule Cytoskeletons Is Mediated Through mTORC1 Signaling. Endocrinology 2017; 158:963-978. [PMID: 28323988 PMCID: PMC5460804 DOI: 10.1210/en.2016-1630] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 01/11/2017] [Indexed: 11/19/2022]
Abstract
A local axis connects the apical ectoplasmic specialization (ES) at the Sertoli-spermatid interface, the basal ES at the blood-testis barrier (BTB), and the basement membrane across the seminiferous epithelium functionally in rat testes. As such, cellular events that take place simultaneously across the epithelium such as spermiation and BTB remodeling that occur at the apical ES and the basal ES, respectively, at stage VIII of the cycle are coordinated. Herein, laminin α2, a structural component of the basement membrane, was found to regulate BTB dynamics. Sertoli cells were cultured in vitro to allow the establishment of a tight junction (TJ) barrier that mimicked the BTB in vivo. Knockdown of laminin α2 by transfecting Sertoli cells with laminin α2-specific short hairpin RNA vs the nontargeting negative control was shown to perturb the Sertoli cell TJ barrier, illustrating laminin α2 was involved in regulating BTB dynamics. This regulatory effect was mediated through mammalian target of rapamycin complex 1 (mTORC1) signaling because the two mTORC1 downstream signaling molecules ribosomal protein S6 and Akt1/2 were activated and inactivated, respectively, consistent with earlier findings that mTORC1 is involved in promoting BTB remodeling. Also, laminin α2 knockdown induced F-actin and microtubule (MT) disorganization through changes in the spatial expression of F-actin regulators actin-related protein 3 and epidermal growth factor receptor pathway substrate 8 vs end-binding protein 1 (a MT plus-end tracking protein, +TIP). These laminin α2 knockdown-mediated effects on F-actin and MT organization was blocked by exposing Sertoli cells to rapamycin, an inhibitor of mTORC1 signaling, and also SC79, an activator of Akt. In summary, laminin α2-mediated regulation on Sertoli cell BTB dynamics is through mTORC1 signaling.
Collapse
Affiliation(s)
- Ying Gao
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York 10065
| | - Haiqi Chen
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York 10065
| | - Wing-yee Lui
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Will M. Lee
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - C. Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York 10065
| |
Collapse
|
12
|
Gao Y, Mruk D, Chen H, Lui WY, Lee WM, Cheng CY. Regulation of the blood-testis barrier by a local axis in the testis: role of laminin α2 in the basement membrane. FASEB J 2017; 31:584-597. [PMID: 27815338 PMCID: PMC5240664 DOI: 10.1096/fj.201600870r] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 10/11/2016] [Indexed: 02/06/2023]
Abstract
Laminin α2 is one of the constituent components of the basement membrane (BM) in adult rat testes. Earlier studies that used a mouse genetic model have shown that a deletion of laminin α2 impedes male fertility by disrupting ectoplasmic specialization (ES; a testis-specific, actin-rich anchoring junction) function along the length of Sertoli cell in the testis. This includes ES at the Sertoli cell-elongating/elongated spermatid interface, which is known as apical ES and possibly the Sertoli-Sertoli cell interface, known as basal ES, at the blood-testis barrier (BTB). Studies have also illustrated that there is a local regulatory axis that functionally links cellular events of spermiation that occur near the luminal edge of tubule lumen at the apical ES and the basal ES/BTB remodeling near the BM at opposite ends of the seminiferous epithelium during the epithelial cycle, known as the apical ES-BTB-BM axis. However, the precise role of BM in this axis remains unknown. Here, we show that laminin α2 in the BM serves as the crucial regulator in this axis as laminin α2, likely its 80-kDa fragment from the C terminus, was found to be transported across the seminiferous epithelium at stages VIII-IX of the epithelial cycle, from the BM to the luminal edge of the tubule, possibly being used to modulate apical ES restructuring at these stages. Of more importance, a knockdown of laminin α2 in Sertoli cells was shown to induce the Sertoli cell tight junction permeability barrier disruption via changes in localization of adhesion proteins at the tight junction and basal ES at the Sertoli cell BTB. These changes were found to be mediated by a disruption of F-actin organization that was induced by changes in the spatiotemporal expression of actin binding/regulatory proteins. Furthermore, laminin α2 knockdown also perturbed microtubule (MT) organization by considerable down-regulation of MT polymerization via changes in the spatiotemporal expression of EB1 (end-binding protein 1), a +TIP (MT plus-end tracking protein). In short, laminin α2 in the BM seems to play a crucial role in the BTB-BM axis by modulating BTB dynamics during spermatogenesis.-Gao, Y., Mruk, D., Chen, H., Lui, W.-Y., Lee, W. M., Cheng, C. Y. Regulation of the blood-testis barrier by a local axis in the testis: role of laminin α2 in the basement membrane.
Collapse
Affiliation(s)
- Ying Gao
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA
| | - Dolores Mruk
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA
| | - Haiqi Chen
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA
| | - Wing-Yee Lui
- School of Biological Sciences, The University of Hong Kong, Hong Kong, China
| | - Will M Lee
- School of Biological Sciences, The University of Hong Kong, Hong Kong, China
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA;
| |
Collapse
|
13
|
Mehta P, Piao X. Adhesion G-protein coupled receptors and extracellular matrix proteins: Roles in myelination and glial cell development. Dev Dyn 2017; 246:275-284. [PMID: 27859941 DOI: 10.1002/dvdy.24473] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 11/08/2016] [Accepted: 11/10/2016] [Indexed: 01/05/2023] Open
Abstract
Adhesion G protein-coupled receptors (aGPCRs) are a large family of transmembrane proteins that play important roles in many processes during development, primarily through cell-cell and cell-extracellular matrix (ECM) interactions. In the nervous system, they have been linked to the complex process of myelination, both in the central and peripheral nervous system. GPR126 is essential in Schwann cell-mediated myelination in the peripheral nervous system (PNS), while GPR56 is involved in oligodendrocyte development central nervous system (CNS) myelination. VLGR1 is another aGPCR that is associated with the expression of myelin-associated glycoprotein (MAG) which has inhibitory effects on the process of nerve repair. The ECM is composed of a vast array of structural proteins, three of which interact specifically with aGPCRs: collagen III/GPR56, collagen IV/GPR126, and laminin-211/GPR126. As druggable targets, aGPCRs are valuable in their ability to unlock treatment for a wide variety of currently debilitating myelin disorders. Developmental Dynamics 246:275-284, 2017. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Paulomi Mehta
- Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Xianhua Piao
- Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| |
Collapse
|
14
|
Wheeler NA, Fuss B. Extracellular cues influencing oligodendrocyte differentiation and (re)myelination. Exp Neurol 2016; 283:512-30. [PMID: 27016069 PMCID: PMC5010977 DOI: 10.1016/j.expneurol.2016.03.019] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 03/03/2016] [Accepted: 03/18/2016] [Indexed: 02/07/2023]
Abstract
There is an increasing number of neurologic disorders found to be associated with loss and/or dysfunction of the CNS myelin sheath, ranging from the classic demyelinating disease, multiple sclerosis, through CNS injury, to neuropsychiatric diseases. The disabling burden of these diseases has sparked a growing interest in gaining a better understanding of the molecular mechanisms regulating the differentiation of the myelinating cells of the CNS, oligodendrocytes (OLGs), and the process of (re)myelination. In this context, the importance of the extracellular milieu is becoming increasingly recognized. Under pathological conditions, changes in inhibitory as well as permissive/promotional cues are thought to lead to an overall extracellular environment that is obstructive for the regeneration of the myelin sheath. Given the general view that remyelination is, even though limited in human, a natural response to demyelination, targeting pathologically 'dysregulated' extracellular cues and their downstream pathways is regarded as a promising approach toward the enhancement of remyelination by endogenous (or if necessary transplanted) OLG progenitor cells. In this review, we will introduce the extracellular cues that have been implicated in the modulation of (re)myelination. These cues can be soluble, part of the extracellular matrix (ECM) or mediators of cell-cell interactions. Their inhibitory and permissive/promotional roles with regard to remyelination as well as their potential for therapeutic intervention will be discussed.
Collapse
Affiliation(s)
- Natalie A Wheeler
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States
| | - Babette Fuss
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States.
| |
Collapse
|
15
|
The extracellular matrix protein laminin α2 regulates the maturation and function of the blood-brain barrier. J Neurosci 2015; 34:15260-80. [PMID: 25392494 DOI: 10.1523/jneurosci.3678-13.2014] [Citation(s) in RCA: 150] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Laminins are major constituents of the gliovascular basal lamina of the blood-brain barrier (BBB); however, the role of laminins in BBB development remains unclear. Here we report that Lama2(-/-) mice, lacking expression of the laminin α2 subunit of the laminin-211 heterotrimer expressed by astrocytes and pericytes, have a defective BBB in which systemically circulated tracer leaks into the brain parenchyma. The Lama2(-/-) vascular endothelium had significant abnormalities, including altered integrity and composition of the endothelial basal lamina, inappropriate expression of embryonic vascular endothelial protein MECA32, substantially reduced pericyte coverage, and tight junction abnormalities. Additionally, astrocytic endfeet were hypertrophic and lacked appropriately polarized aquaporin4 channels. Laminin-211 appears to mediate these effects at least in part by dystroglycan receptor interactions, as preventing dystroglycan expression in neural cells led to a similar set of BBB abnormalities and gliovascular disturbances, which additionally included perturbed vascular endothelial glucose transporter-1 localization. These findings provide insight into the cell and molecular changes that occur in congenital muscular dystrophies caused by Lama2 mutations or inappropriate dystroglycan post-translational modifications, which have accompanying brain abnormalities, including seizures. Our results indicate a novel role for laminin-dystroglycan interactions in the cooperative integration of astrocytes, endothelial cells, and pericytes in regulating the BBB.
Collapse
|
16
|
Kevelam SH, van Engelen BG, van Berkel CG, Küsters B, van der Knaap MS. LAMA2
mutations in adult-onset muscular dystrophy with leukoencephalopathy. Muscle Nerve 2014; 49:616-7. [DOI: 10.1002/mus.24147] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Revised: 11/28/2013] [Accepted: 12/04/2013] [Indexed: 11/11/2022]
Affiliation(s)
- Sietske H. Kevelam
- Department of Child Neurology; VU Medical Center; Amsterdam The Netherlands
- Department of Clinical Genetics; Medical Genomics Section, Amsterdam; The Netherlands
| | - Baziel G.M. van Engelen
- Department of Neurology; Radboud University Nijmegen Medical Center; Nijmegen The Netherlands
| | | | - Benno Küsters
- Department of Pathology; Radboud University Nijmegen Medical Center; Nijmegen The Netherlands
- Department of Pathology; Maastricht University Medical Center; Maastricht The Netherlands
| | | |
Collapse
|
17
|
Aoki Y, Nagata T, Yokota T, Nakamura A, Wood MJA, Partridge T, Takeda S. Highly efficient in vivo delivery of PMO into regenerating myotubes and rescue in laminin-α2 chain-null congenital muscular dystrophy mice. Hum Mol Genet 2013; 22:4914-28. [PMID: 23882132 PMCID: PMC7108576 DOI: 10.1093/hmg/ddt341] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Phosphorodiamidate morpholino oligomer (PMO)-mediated exon skipping is among the more promising approaches to the treatment of several neuromuscular disorders including Duchenne muscular dystrophy. The main weakness of this approach arises from the low efficiency and sporadic nature of the delivery of charge-neutral PMO into muscle fibers, the mechanism of which is unknown. In this study, to test our hypothesis that muscle fibers take up PMO more efficiently during myotube formation, we induced synchronous muscle regeneration by injection of cardiotoxin into the tibialis anterior muscle of Dmd exon 52-deficient mdx52 and wild-type mice. Interestingly, by in situ hybridization, we detected PMO mainly in embryonic myosin heavy chain-positive regenerating fibers. In addition, we showed that PMO or 2′-O-methyl phosphorothioate is taken up efficiently into C2C12 myotubes when transfected 24–72 h after the induction of differentiation but is poorly taken up into undifferentiated C2C12 myoblasts suggesting efficient uptake of PMO in the early stages of C2C12 myotube formation. Next, we tested the therapeutic potential of PMO for laminin-α2 chain-null dy3K/dy3K mice: a model of merosin-deficient congenital muscular dystrophy (MDC1A) with active muscle regeneration. We confirmed the recovery of laminin-α2 chain and slightly prolonged life span following skipping of the mutated exon 4 in dy3K/dy3K mice. These findings support the idea that PMO entry into fibers is dependent on a developmental stage in myogenesis rather than on dystrophinless muscle membranes and provide a platform for developing PMO-mediated therapies for a variety of muscular disorders, such as MDC1A, that involve active muscle regeneration.
Collapse
Affiliation(s)
- Yoshitsugu Aoki
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Ogawa-Higashi 4-1-1, Kodaira, Tokyo 187-8502, Japan
| | | | | | | | | | | | | |
Collapse
|
18
|
Miciak JJ, Warsing LC, Tibbs ME, Jasper JR, Jampel SB, Malik FI, Tankersley C, Wagner KR. Fast skeletal muscle troponin activator in the dy2J muscular dystrophy model. Muscle Nerve 2013; 48:279-85. [PMID: 23512724 DOI: 10.1002/mus.23848] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/12/2013] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Tirasemtiv is a novel small molecule activator of the fast skeletal muscle troponin complex that produces sensitization of the sarcomere to calcium. Tirasemtiv is currently in Phase II clinical trials for neuromuscular disease. METHODS We conducted a blinded, randomized, placebo-controlled preclinical study of the effect of tirasemtiv on forearm grip strength, endurance, respiratory physiology, and muscle pathology in adequate sample sizes of the Lama2(dy-2J) mouse model of congenital muscular dystrophy. RESULTS Mice receiving a high dose of tirasemtiv had significantly higher muscle fiber cross-sectional area and respiratory response to CO₂ stimulation at 16 weeks than mice on low dose or placebo. There were no changes in muscle pathology, serum creatine kinase, strength, endurance, or respiration following long-term treatment. CONCLUSIONS We conclude that tirasemtiv influences the structure of the skeletal muscle fiber in this model of muscular dystrophy but does not impact muscle function, as evaluated in this study.
Collapse
Affiliation(s)
- Jessica J Miciak
- Center for Genetic Muscle Disorders, The Kennedy Krieger Institute, 707 North Broadway, Baltimore, Maryland 21205, USA
| | | | | | | | | | | | | | | |
Collapse
|
19
|
Masaki T. Polarization and myelination in myelinating glia. ISRN NEUROLOGY 2012; 2012:769412. [PMID: 23326681 PMCID: PMC3544266 DOI: 10.5402/2012/769412] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 11/13/2012] [Indexed: 01/13/2023]
Abstract
Myelinating glia, oligodendrocytes in central nervous system and Schwann cells in peripheral nervous system, form myelin sheath, a multilayered membrane system around axons enabling salutatory nerve impulse conduction and maintaining axonal integrity. Myelin sheath is a polarized structure localized in the axonal side and therefore is supposed to be formed based on the preceding polarization of myelinating glia. Thus, myelination process is closely associated with polarization of myelinating glia. However, cell polarization has been less extensively studied in myelinating glia than other cell types such as epithelial cells. The ultimate goal of this paper is to provide insights for the field of myelination research by applying the information obtained in polarity study in other cell types, especially epithelial cells, to cell polarization of myelinating glia. Thus, in this paper, the main aspects of cell polarization study in general are summarized. Then, they will be compared with polarization in oligodendrocytes. Finally, the achievements obtained in polarization study for epithelial cells, oligodendrocytes, and other types of cells will be translated into polarization/myelination process by Schwann cells. Then, based on this model, the perspectives in the study of Schwann cell polarization/myelination will be discussed.
Collapse
Affiliation(s)
- Toshihiro Masaki
- Department of Medical Science, Teikyo University of Science, 2-2-1 Senju-Sakuragi, Adachi-ku, Tokyo 120-0045, Japan
| |
Collapse
|
20
|
Meinen S, Lin S, Ruegg MA. Angiotensin II type 1 receptor antagonists alleviate muscle pathology in the mouse model for laminin-α2-deficient congenital muscular dystrophy (MDC1A). Skelet Muscle 2012; 2:18. [PMID: 22943509 PMCID: PMC3598380 DOI: 10.1186/2044-5040-2-18] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 07/31/2012] [Indexed: 12/22/2022] Open
Abstract
Background Laminin-α2-deficient congenital muscular dystrophy (MDC1A) is a severe muscle-wasting disease for which no curative treatment is available. Antagonists of the angiotensin II receptor type 1 (AT1), including the anti-hypertensive drug losartan, have been shown to block also the profibrotic action of transforming growth factor (TGF)-β and thereby ameliorate disease progression in mouse models of Marfan syndrome. Because fibrosis and failure of muscle regeneration are the main reasons for the severe disease course of MDC1A, we tested whether L-158809, an analog derivative of losartan, could ameliorate the dystrophy in dyW/dyW mice, the best-characterized model of MDC1A. Methods L-158809 was given in food to dyW/dyW mice at the age of 3 weeks, and the mice were analyzed at the age of 6 to 7 weeks. We examined the effect of L-158809 on muscle histology and on muscle regeneration after injury as well as the locomotor activity and muscle strength of the mice. Results We found that TGF-β signaling in the muscles of the dyW/dyW mice was strongly increased, and that L-158809 treatment suppressed this signaling. Consequently, L-158809 reduced fibrosis and inflammation in skeletal muscle of dyW/dyW mice, and largely restored muscle regeneration after toxin-induced injury. Mice showed improvement in their locomotor activity and grip strength, and their body weight was significantly increased. Conclusion These data provide evidence that AT1 antagonists ameliorate several hallmarks of MDC1A in dyW/dyW mice, the best-characterized mouse model for this disease. Because AT1 antagonists are well tolerated in humans and widely used in clinical practice, these results suggest that losartan may offer a potential future treatment of patients with MDC1A.
Collapse
Affiliation(s)
- Sarina Meinen
- Biozentrum, University of Basel, Basel, Switzerland.
| | | | | |
Collapse
|
21
|
Gupta VA, Kawahara G, Myers JA, Chen AT, Hall TE, Manzini MC, Currie PD, Zhou Y, Zon LI, Kunkel LM, Beggs AH. A splice site mutation in laminin-α2 results in a severe muscular dystrophy and growth abnormalities in zebrafish. PLoS One 2012; 7:e43794. [PMID: 22952766 PMCID: PMC3428294 DOI: 10.1371/journal.pone.0043794] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Accepted: 07/24/2012] [Indexed: 11/18/2022] Open
Abstract
Congenital muscular dystrophy (CMD) is a clinically and genetically heterogeneous group of inherited muscle disorders. In patients, muscle weakness is usually present at or shortly after birth and is progressive in nature. Merosin deficient congenital muscular dystrophy (MDC1A) is a form of CMD caused by a defect in the laminin-α2 gene (LAMA2). Laminin-α2 is an extracellular matrix protein that interacts with the dystrophin-dystroglycan (DGC) complex in membranes providing stability to muscle fibers. In an N-ethyl-N-nitrosourea mutagenesis screen to develop zebrafish models of neuromuscular diseases, we identified a mutant fish that exhibits severe muscular dystrophy early in development. Genetic mapping identified a splice site mutation in the lama2 gene. This splice site is highly conserved in humans and this mutation results in mis-splicing of RNA and a loss of protein function. Homozygous lama2 mutant zebrafish, designated lama2cl501/cl501, exhibited reduced motor function and progressive degeneration of skeletal muscles and died at 8–15 days post fertilization. The skeletal muscles exhibited damaged myosepta and detachment of myofibers in the affected fish. Laminin-α2 deficiency also resulted in growth defects in the brain and eye of the mutant fish. This laminin-α2 deficient mutant fish represents a novel disease model to develop therapies for modulating splicing defects in congenital muscular dystrophies and to restore the muscle function in human patients with CMD.
Collapse
Affiliation(s)
- Vandana A. Gupta
- Genomics Program and Division of Genetics, Boston Children’s Hospital, Harvard Medical School, The Manton Center for Orphan Disease Research, Boston, Massachusetts, United States of America
| | - Genri Kawahara
- Genomics Program and Division of Genetics, Boston Children’s Hospital, Harvard Medical School, The Manton Center for Orphan Disease Research, Boston, Massachusetts, United States of America
| | - Jennifer A. Myers
- Genomics Program and Division of Genetics, Boston Children’s Hospital, Harvard Medical School, The Manton Center for Orphan Disease Research, Boston, Massachusetts, United States of America
| | - Aye T. Chen
- Stem Cell Program and Pediatric Hematology/Oncology, Boston Children’s Hospital and Dana Farber Cancer Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Thomas E. Hall
- Australian Regenerative Medicine Institute, Monash University, Clayton Campus, Victoria, Australia
| | - M. Chiara Manzini
- Genomics Program and Division of Genetics, Boston Children’s Hospital, Harvard Medical School, The Manton Center for Orphan Disease Research, Boston, Massachusetts, United States of America
| | - Peter D. Currie
- Australian Regenerative Medicine Institute, Monash University, Clayton Campus, Victoria, Australia
| | - Yi Zhou
- Stem Cell Program and Pediatric Hematology/Oncology, Boston Children’s Hospital and Dana Farber Cancer Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Leonard I. Zon
- Stem Cell Program and Pediatric Hematology/Oncology, Boston Children’s Hospital and Dana Farber Cancer Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, Massachusetts, United States of America
- Howard Hughes Medical Institute, San Francisco, California, United States of America
| | - Louis M. Kunkel
- Genomics Program and Division of Genetics, Boston Children’s Hospital, Harvard Medical School, The Manton Center for Orphan Disease Research, Boston, Massachusetts, United States of America
| | - Alan H. Beggs
- Genomics Program and Division of Genetics, Boston Children’s Hospital, Harvard Medical School, The Manton Center for Orphan Disease Research, Boston, Massachusetts, United States of America
- * E-mail:
| |
Collapse
|
22
|
Relucio J, Menezes MJ, Miyagoe-Suzuki Y, Takeda S, Colognato H. Laminin regulates postnatal oligodendrocyte production by promoting oligodendrocyte progenitor survival in the subventricular zone. Glia 2012; 60:1451-67. [PMID: 22706957 DOI: 10.1002/glia.22365] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Accepted: 05/10/2012] [Indexed: 01/28/2023]
Abstract
The laminin family of extracellular matrix proteins are expressed broadly during embryonic brain development, but are enriched at ventricular and pial surfaces where laminins mediate radial glial attachment during corticogenesis. In the adult brain, however, laminin distribution is restricted, yet is found within the vascular basal lamina and associated fractones of the ventricular zone (VZ)-subventricular zone (SVZ) stem cell niche, where laminins regulate adult neural progenitor cell proliferation. It remains unknown, however, if laminins regulate the wave of oligodendrogenesis that occurs in the neonatal/early postnatal VZ-SVZ. Here we report that Lama2, the gene that encodes the laminin α2-subunit, regulates postnatal oligodendrogenesis. At birth, Lama2-/- mice had significantly higher levels of dying oligodendrocyte progenitor cells (OPCs) in the OPC germinal zone of the dorsal SVZ. This translated into fewer OPCs, both in the dorsal SVZ well as in an adjacent developing white matter tract, the corpus callosum. In addition, intermediate progenitor cells that give rise to OPCs in the Lama2-/- VZ-SVZ were mislocalized and proliferated nearer to the ventricle surface. Later, delays in oligodendrocyte maturation (with accompanying OPC accumulation), were observed in the Lama2-/- corpus callosum, leading to dysmyelination by postnatal day 21. Together these data suggest that prosurvival laminin interactions in the developing postnatal VZ-SVZ germinal zone regulate the ability, or timing, of oligodendrocyte production to occur appropriately.
Collapse
Affiliation(s)
- Jenne Relucio
- Department of Pharmacology, Stony Brook University, Stony Brook, New York, 11794, USA
| | | | | | | | | |
Collapse
|
23
|
Gómez-Díaz B, Rosas-Vargas H, Roque-Ramírez B, Meza-Espinoza P, Ruano-Calderón LA, Fernández-Valverde F, Escalante-Bautista D, Escobar-Cedillo RE, Sánchez-Chapul L, Vargas-Cañas S, López-Hernández LB, Bahena-Martínez E, Luna-Angulo AB, Canto P, Coral-Vázquez RM. Immunodetection analysis of muscular dystrophies in Mexico. Muscle Nerve 2012; 45:338-45. [DOI: 10.1002/mus.22314] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
24
|
Eyermann C, Czaplinski K, Colognato H. Dystroglycan promotes filopodial formation and process branching in differentiating oligodendroglia. J Neurochem 2012; 120:928-47. [PMID: 22117643 DOI: 10.1111/j.1471-4159.2011.07600.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
During central nervous system (CNS) development, individual oligodendrocytes myelinate multiple axons, thus requiring the outgrowth and extensive branching of oligodendroglial processes. Laminin (Lm)-deficient mice have a lower percentage of myelinated axons, which may indicate a defect in the ability to properly extend and branch processes. It remains unclear, however, to what extent extracellular matrix (ECM) receptors contribute to oligodendroglial process remodeling itself. In the current study, we report that the ECM receptor dystroglycan is necessary for Lm enhancement of filopodial formation, process outgrowth, and process branching in differentiating oligodendroglia. During early oligodendroglial differentiation, the disruption of dystroglycan-Lm interactions, via blocking antibodies or dystroglycan small interfering RNA (siRNA), resulted in decreased filopodial number and length, decreased process length, and decreased numbers of primary and secondary processes. Later in oligodendrocyte differentiation, dystroglycan-deficient cells developed fewer branches, thus producing less complex networks of processes as determined by Sholl analysis. In newly differentiating oligodendroglia, dystroglycan was localized in filopodial tips, whereas, in more mature oligodendrocytes, dystroglycan was enriched in focal adhesion kinase (FAK)-positive focal adhesion structures. These results suggest that dystroglycan-Lm interactions influence oligodendroglial process dynamics and therefore may regulate the myelination capacity of individual oligodendroglia.
Collapse
|
25
|
Meinen S, Lin S, Thurnherr R, Erb M, Meier T, Rüegg MA. Apoptosis inhibitors and mini-agrin have additive benefits in congenital muscular dystrophy mice. EMBO Mol Med 2011; 3:465-79. [PMID: 21674808 PMCID: PMC3377088 DOI: 10.1002/emmm.201100151] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Revised: 04/29/2011] [Accepted: 05/17/2011] [Indexed: 11/18/2022] Open
Abstract
Mutations in LAMA2 cause a severe form of congenital muscular dystrophy, called MDC1A. Studies in mouse models have shown that transgenic expression of a designed, miniaturized form of the extracellular matrix molecule agrin (‘mini-agrin’) or apoptosis inhibition by either overexpression of Bcl2 or application of the pharmacological substance omigapil can ameliorate the disease. Here, we tested whether mini-agrin and anti-apoptotic agents act on different pathways and thus exert additive benefits in MDC1A mouse models. By combining mini-agrin with either transgenic Bcl2 expression or oral omigapil application, we show that the ameliorating effect of mini-agrin, which acts by restoring the mechanical stability of muscle fibres and, thereby, reduces muscle fibre breakdown and concomitant fibrosis, is complemented by apoptosis inhibitors, which prevent the loss of muscle fibres. Treatment of mice with both agents results in improved muscle regeneration and increased force. Our results show that the combination of mini-agrin and anti-apoptosis treatment has beneficial effects that are significantly bigger than the individual treatments and suggest that such a strategy might also be applicable to MDC1A patients.
Collapse
|
26
|
Doe JA, Wuebbles RD, Allred ET, Rooney JE, Elorza M, Burkin DJ. Transgenic overexpression of the α7 integrin reduces muscle pathology and improves viability in the dy(W) mouse model of merosin-deficient congenital muscular dystrophy type 1A. J Cell Sci 2011; 124:2287-97. [PMID: 21652631 DOI: 10.1242/jcs.083311] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Merosin-deficient congenital muscular dystrophy 1A (MDC1A) is a devastating neuromuscular disease that results in children being confined to a wheelchair, requiring ventilator assistance to breathe and premature death. MDC1A is caused by mutations in the LAMA2 gene, which results in the partial or complete loss of laminin-211 and laminin-221, the major laminin isoforms found in the basal lamina of skeletal muscle. MDC1A patients exhibit reduced α7β1 integrin; however, it is unclear how the secondary loss of α7β1 integrin contributes to MDC1A disease progression. To investigate whether restoring α7 integrin expression can alleviate the myopathic phenotype observed in MDC1A, we produced transgenic mice that overexpressed the α7 integrin in the skeletal muscle of the dy(W⁻/⁻) mouse model of MDC1A. Enhanced expression of the α7 integrin restored sarcolemmal localization of the α7β1 integrin to laminin-α2-deficient myofibers, changed the composition of the muscle extracellular matrix, reduced muscle pathology, maintained muscle strength and function and improved the life expectancy of dy(W⁻/⁻) mice. Taken together, these results indicate that enhanced expression of α7 integrin prevents muscle disease progression through augmentation and/or stabilization of the existing extracellular matrix in laminin-α2-deficient mice, and strategies that increase α7 integrin in muscle might provide an innovative approach for the treatment of MDC1A.
Collapse
Affiliation(s)
- Jinger A Doe
- Department of Pharmacology, University of Nevada School of Medicine, Reno, NV 89557, USA
| | | | | | | | | | | |
Collapse
|
27
|
Nevo Y, Aga-Mizrachi S, Elmakayes E, Yanay N, Ettinger K, Elbaz M, Brunschwig Z, Dadush O, Elad-Sfadia G, Haklai R, Kloog Y, Chapman J, Reif S. The Ras antagonist, farnesylthiosalicylic acid (FTS), decreases fibrosis and improves muscle strength in dy/dy mouse model of muscular dystrophy. PLoS One 2011; 6:e18049. [PMID: 21445359 PMCID: PMC3062565 DOI: 10.1371/journal.pone.0018049] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Accepted: 02/23/2011] [Indexed: 12/01/2022] Open
Abstract
The Ras superfamily of guanosine-triphosphate (GTP)-binding proteins regulates a diverse spectrum of intracellular processes involved in inflammation and fibrosis. Farnesythiosalicylic acid (FTS) is a unique and potent Ras inhibitor which decreased inflammation and fibrosis in experimentally induced liver cirrhosis and ameliorated inflammatory processes in systemic lupus erythematosus, neuritis and nephritis animal models. FTS effect on Ras expression and activity, muscle strength and fibrosis was evaluated in the dy2J/dy2J mouse model of merosin deficient congenital muscular dystrophy. The dy2J/dy2J mice had significantly increased RAS expression and activity compared with the wild type mice. FTS treatment significantly decreased RAS expression and activity. In addition, phosphorylation of ERK, a Ras downstream protein, was significantly decreased following FTS treatment in the dy2J/dy2J mice. Clinically, FTS treated mice showed significant improvement in hind limb muscle strength measured by electronic grip strength meter. Significant reduction of fibrosis was demonstrated in the treated group by quantitative Sirius Red staining and lower muscle collagen content. FTS effect was associated with significantly inhibition of both MMP-2 and MMP-9 activities. We conclude that active RAS inhibition by FTS was associated with attenuated fibrosis and improved muscle strength in the dy2J/dy2J mouse model of congenital muscular dystrophy.
Collapse
Affiliation(s)
- Yoram Nevo
- Pediatric Neuromuscular Laboratory and the Neuropediatric Unit, Hadassah Hebrew University Hospital, Jerusalem, Israel.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Abstract
Integrins are adhesive proteins that have evolved to mediate cell-cell and cell-matrix communication that is indispensable for development and postnatal physiology. Despite their widespread expression, the genetic deletion of specific integrin family members in lower organisms as well as mammals leads to relatively distinct abnormalities. Many of the processes in which integrins participate have a requirement for strong adhesion coincident with times of mechanical stress. In Drosophila, the absence of specific integrins leads to detachment of muscle from the gut and body wall and separation of the two epithelial layers in the wing. In mice and humans, a deletion of either subunit of the laminin-binding integrin, α6β4 leads to severe skin blistering and defects in other epithelial layers. In addition, integrins have also evolved to serve more subspecialized roles ranging from the establishment of a stem cell niche in Drosophila and mammals, to the regulation of pathogenic tumor vascularization, platelet adhesion, and leukocyte transmigration in mammalian systems. However, some cells seem to function normally in the absence of all integrins, as revealed by the very surprising finding that deletion of all the major integrin types on dendritic cells of mice has no effect on the ability of these cells to migrate within the interstitium of the skin and enter into lymphatics. In addition to serving as transmembrane mechanical links, integrins in vertebrates synergize with a number of receptors including growth factor receptors, to enhance responses. This leads to the activation of a large signaling network that affects cell proliferation and differentiation, as well as cell shape and migration. In vivo studies, in lower organisms, knockout mouse models as well as in inherited human diseases together have provided important insights into how this major, primordial family of adhesion receptors have remained true to their name "integrins" as their diverse functions have in common the ability to integrate extracellular stimuli into intracellular signals that affect cell behavior.
Collapse
|
29
|
Wiradjaja F, DiTommaso T, Smyth I. Basement membranes in development and disease. ACTA ACUST UNITED AC 2010; 90:8-31. [PMID: 20301220 DOI: 10.1002/bdrc.20172] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Basement membranes (BMs) are specializations of the extracellular matrix that act as key mediators of development and disease. Their sheet like protein matrices typically serve to separate epithelial or endothelial cell layers from underlying mesenchymal tissues, providing both a biophysical support to overlying tissue as well as a hub to promote and regulate cell-cell and cell-protein interactions. In the latter context, the BM is increasingly being recognized as a mediator of growth factor interactions during development. In this review, we discuss recent findings regarding the structure of the BM and its roles in mediating the normal development of the embryo, and we examine congenital diseases affecting the BM which impact embryonic development and health in later life.
Collapse
Affiliation(s)
- Fenny Wiradjaja
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Australia
| | | | | |
Collapse
|
30
|
Biological role of dystroglycan in Schwann cell function and its implications in peripheral nervous system diseases. J Biomed Biotechnol 2010; 2010:740403. [PMID: 20625412 PMCID: PMC2896880 DOI: 10.1155/2010/740403] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2009] [Accepted: 04/20/2010] [Indexed: 11/17/2022] Open
Abstract
Dystroglycan is a central component of the dystrophin-glycoprotein complex (DGC) that links extracellular matrix with cytoskeleton, expressed in a variety of fetal and adult tissues. Dystroglycan plays diverse roles in development and homeostasis including basement membrane formation, epithelial morphogenesis, membrane stability, cell polarization, and cell migration. In this paper, we will focus on biological role of dystroglycan in Schwann cell function, especially myelination. First, we review the molecular architecture of DGC in Schwann cell abaxonal membrane. Then, we will review the loss-of-function studies using targeted mutagenesis, which have revealed biological functions of each component of DGC in Schwann cells. Based on these findings, roles of dystroglycan in Schwann cell function, in myelination in particular, and its implications in diseases will be discussed in detail. Finally, in view of the fact that understanding the role of dystroglycan in Schwann cells is just beginning, future perspectives will be discussed.
Collapse
|
31
|
Improved muscle strength and mobility in the dy(2J)/dy(2J) mouse with merosin deficient congenital muscular dystrophy treated with Glatiramer acetate. Neuromuscul Disord 2010; 20:267-72. [PMID: 20304648 DOI: 10.1016/j.nmd.2010.02.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Revised: 01/29/2010] [Accepted: 02/01/2010] [Indexed: 01/01/2023]
Abstract
The therapeutic effect of Glatiramer acetate, an immune modulating agent, was evaluated in the dy(2J)/dy(2J) mouse with merosin deficient congenital muscular dystrophy, which is a milder variant of the dy/dy mouse. The treated mice showed significant improvement in hind limb muscle strength measured by electronic grip strength meter and in motor performance quantified by video detection software. Glatiramer acetate treatment was associated with significantly increased expression of regeneration transcription factors MyoD and myogenin, and attenuation of the fibrosis markers vimentin and fibronectin. No effective treatment is currently available in congenital muscular dystrophy and Glatiramer acetate may present a new potential treatment for this disorder.
Collapse
|
32
|
Nagra G, Koh L, Aubert I, Kim M, Johnston M. Intraventricular injection of antibodies to β1-integrins generates pressure gradients in the brain favoring hydrocephalus development in rats. Am J Physiol Regul Integr Comp Physiol 2009; 297:R1312-21. [DOI: 10.1152/ajpregu.00307.2009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In some tissues, the injection of antibodies to the β1-integrins leads to a reduction in interstitial fluid pressure, indicating an active role for the extracellular matrix in tissue pressure regulation. If perturbations of the matrix occur in the periventricular area of the brain, a comparable lowering of interstitial pressures may induce transparenchymal pressure gradients favoring ventricular expansion. To examine this concept, we measured periventricular (parenchymal) and ventricular pressures with a servo-null micropipette system (2-μm tip) in adult Wistar rats before and after anti-integrin antibodies or IgG/IgM isotype controls were injected into a lateral ventricle. In a second group, the animals were kept for 2 wk after similar injections and after euthanization, the brains were removed and assessed for hydrocephalus. In experiments in which antibodies to β1-integrins ( n = 10) but not isotype control IgG/IgM ( n = 7) were injected, we observed a decline in periventricular pressures relative to the preinjection values. Under similar circumstances, ventricular pressures were elevated ( n = 10) and were significantly greater than those in the periventricular interstitium. We estimated ventricular to periventricular pressure gradients of up to 4.3 cmH2O. In the chronic preparations, we observed enlarged ventricles in many of the animals that received injections of anti-integrin antibodies (21 of 29 animals; 72%) but not in any animal receiving the isotype controls. We conclude that modulation/disruption of β1-integrin-matrix interactions in the brain generates pressure gradients favoring ventricular expansion, suggesting a novel mechanism for hydrocephalus development.
Collapse
Affiliation(s)
- Gurjit Nagra
- Brain Sciences Program and Department of Laboratory Medicine and Pathobiology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
| | - Lena Koh
- Brain Sciences Program and Department of Laboratory Medicine and Pathobiology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
| | - Isabelle Aubert
- Brain Sciences Program and Department of Laboratory Medicine and Pathobiology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
| | - Minhui Kim
- Brain Sciences Program and Department of Laboratory Medicine and Pathobiology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
| | - Miles Johnston
- Brain Sciences Program and Department of Laboratory Medicine and Pathobiology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
33
|
Vishnudas VK, Miller JB. Ku70 regulates Bax-mediated pathogenesis in laminin-alpha2-deficient human muscle cells and mouse models of congenital muscular dystrophy. Hum Mol Genet 2009; 18:4467-77. [PMID: 19692349 DOI: 10.1093/hmg/ddp399] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The severely debilitating disease Congenital Muscular Dystrophy Type 1A (MDC1A) is caused by mutations in the gene encoding laminin-alpha2. Bax-mediated muscle cell death is a significant contributor to the severe neuromuscular pathology seen in the Lama2-null mouse model of MDC1A. To extend our understanding of pathogenesis due to laminin-alpha2-deficiency, we have now analyzed molecular mechanisms of Bax regulation in normal and laminin-alpha2-deficient muscles and cells, including myogenic cells obtained from patients with a clinical diagnosis of MDC1A. In mouse myogenic cells, we found that, as in non-muscle cells, Bax co-immunoprecipitated with the multifunctional protein Ku70. In addition, cell permeable pentapeptides designed from Ku70, termed Bax-inhibiting peptides (BIPs), inhibited staurosporine-induced Bax translocation and cell death in mouse myogenic cells. We also found that acetylation of Ku70, which can inhibit binding to Bax and can be an indicator of increased susceptibility to cell death, was more abundant in Lama2-null than in normal mouse muscles. Furthermore, myotubes formed in culture from human laminin-alpha2-deficient patient myoblasts produced high levels of activated caspase-3 when grown on poly-L-lysine, but not when grown on a laminin-alpha2-containing substrate or when treated with BIPs. Finally, cytoplasmic Ku70 in human laminin-alpha2-deficient myotubes was both reduced in amount and more highly acetylated than in normal myotubes. Increased susceptibility to cell death thus appears to be an intrinsic property of human laminin-alpha2-deficient myotubes. These results identify Ku70 as a regulator of Bax-mediated pathogenesis and a therapeutic target in laminin-alpha2-deficiency.
Collapse
Affiliation(s)
- Vivek K Vishnudas
- Neuromuscular Biology & Disease Group, Boston Biomedical Research Institute, 64 Grove Street, Watertown, MA 02478, USA
| | | |
Collapse
|
34
|
Páez MC, González MJ, Serrano NC, Shoenfeld Y, Anaya JM. Physiological and pathological implications of laminins: From the gene to the protein. Autoimmunity 2009; 40:83-94. [PMID: 17453709 DOI: 10.1080/08916930600911519] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The extracellular matrix plays an important role in modulating the behavior of cells with which it interacts. There are a number of families of extracellular matrix (ECM) proteins including collagens, proteoglycans and laminins (LM). LM are the major component of the basal lamina (BL). Here, we review the current knowledge on their structure, self-assembly, binding mechanisms, diverse tissue-expression patterns and its impact on pathology. Studies and hypothesis exploring the role of LM and their polymorphic genes on autoimmune diseases (AIDs) such as systemic lupus erythematosus and Sjögren's syndrome (SS) are also discussed.
Collapse
Affiliation(s)
- María-Carolina Páez
- Biomedical Research Center, School of Medicine at Universidad Autónoma de Bucaramanga, Bucaramanga, Colombia
| | | | | | | | | |
Collapse
|
35
|
Chae JH, Lee JS, Hwang H, Kim KJ, Hwang YS, Park JD, Cheon JE, Kim IO, Choe GY, Park SH. Merosin-deficient congenital muscular dystrophy in Korea. Brain Dev 2009; 31:341-6. [PMID: 18723302 DOI: 10.1016/j.braindev.2008.06.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2008] [Revised: 05/19/2008] [Accepted: 06/15/2008] [Indexed: 11/29/2022]
Abstract
Congenital muscular dystrophy (CMD) is a clinically and genetically heterogeneous group of muscle disorders, presenting at birth or early infancy with hypotonia, muscle weakness, joint contractures, and dystrophic changes in the muscles. Merosin-deficient CMD (MDCMD) is rare in Asian populations, but more common in Caucasians, comprising about 50% of CMDs. We report, for the first time in Korea, eight patients with merosin-deficient CMD, confirmed by immunohistochemical staining of muscle or skin samples. We also describe their wide spectrum of clinical features and neuroimaging findings. Among 35 patients diagnosed as CMD, almost 23% of them were proved to have MDCMD with typical phenotypic presentation. We infer that prevalence of MDCMD in Korea may not be as low as expected. One of the patients was diagnosed by skin biopsy, which is good alternative for diagnosis of MDCMD.
Collapse
Affiliation(s)
- Jong-Hee Chae
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Republic of Korea
| | | | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Girgenrath M, Beermann ML, Vishnudas VK, Homma S, Miller JB. Pathology is alleviated by doxycycline in a laminin-alpha2-null model of congenital muscular dystrophy. Ann Neurol 2009; 65:47-56. [PMID: 19086074 DOI: 10.1002/ana.21523] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Congenital muscular dystrophy type 1A is an autosomal recessive disease that is caused by loss-of-function mutations in the laminin-alpha2 gene, and results in motor nerve and skeletal muscle dysfunction. In a previous study, we used genetic modifications to show that inappropriate induction of apoptosis was a significant contributor to pathogenesis in a laminin-alpha2-deficient mouse model of congenital muscular dystrophy type 1A. To identify a possible pharmacological therapy for laminin-alpha2 deficiency, we designed this study to determine whether treatment with minocycline or doxycycline, which are tetracycline derivatives reported to have antiapoptotic effects in mammals, would significantly increase lifespan and improve neuromuscular function in laminin-alpha2-deficient mice. METHODS Mice that were homozygous for a targeted, inactivating mutation of the laminin-alpha2 gene were placed into control, minocycline-treated, or doxycycline-treated groups. Drug treatment began within 2 weeks of birth, and the progression of disease was followed over time using behavioral, growth, histological, and molecular assays. RESULTS We found that treatment with either minocycline or doxycycline increased the median lifespan of laminin-alpha2-null mice from approximately 32 days to approximately 70 days. Furthermore, doxycycline improved postnatal growth rate and delayed the onset of hind-limb paralysis. Doxycycline-treated laminin-alpha2-deficient muscles had increased Akt phosphorylation, decreased inflammation, and decreased levels of Bax protein, terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling-positive myonuclei, and activated caspase-3. INTERPRETATION Doxycycline or other drugs with similar functional profiles may be a possible route to improving neuromuscular dysfunction caused by laminin-alpha2-deficiency.
Collapse
|
37
|
Oliveira J, Santos R, Soares-Silva I, Jorge P, Vieira E, Oliveira ME, Moreira A, Coelho T, Ferreira JC, Fonseca MJ, Barbosa C, Prats J, Aríztegui ML, Martins ML, Moreno T, Heinimann K, Barbot C, Pascual-Pascual SI, Cabral A, Fineza I, Santos M, Bronze-da-Rocha E. LAMA2 gene analysis in a cohort of 26 congenital muscular dystrophy patients. Clin Genet 2008; 74:502-12. [DOI: 10.1111/j.1399-0004.2008.01068.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
38
|
|
39
|
Meinen S, Barzaghi P, Lin S, Lochmüller H, Ruegg MA. Linker molecules between laminins and dystroglycan ameliorate laminin-alpha2-deficient muscular dystrophy at all disease stages. ACTA ACUST UNITED AC 2007; 176:979-93. [PMID: 17389231 PMCID: PMC2064083 DOI: 10.1083/jcb.200611152] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mutations in laminin-α2 cause a severe congenital muscular dystrophy, called MDC1A. The two main receptors that interact with laminin-α2 are dystroglycan and α7β1 integrin. We have previously shown in mouse models for MDC1A that muscle-specific overexpression of a miniaturized form of agrin (mini-agrin), which binds to dystroglycan but not to α7β1 integrin, substantially ameliorates the disease (Moll, J., P. Barzaghi, S. Lin, G. Bezakova, H. Lochmuller, E. Engvall, U. Muller, and M.A. Ruegg. 2001. Nature. 413:302–307; Bentzinger, C.F., P. Barzaghi, S. Lin, and M.A. Ruegg. 2005. Matrix Biol. 24:326–332.). Now we show that late-onset expression of mini-agrin still prolongs life span and improves overall health, although not to the same extent as early expression. Furthermore, a chimeric protein containing the dystroglycan-binding domain of perlecan has the same activities as mini-agrin in ameliorating the disease. Finally, expression of full-length agrin also slows down the disease. These experiments are conceptual proof that linking the basement membrane to dystroglycan by specifically designed molecules or by endogenous ligands, could be a means to counteract MDC1A at a progressed stage of the disease, and thus opens new possibilities for the development of treatment options for this muscular dystrophy.
Collapse
MESH Headings
- Agrin/genetics
- Agrin/metabolism
- Animals
- Basement Membrane/drug effects
- Basement Membrane/metabolism
- Binding Sites/physiology
- Cells, Cultured
- Chick Embryo
- Disease Models, Animal
- Disease Progression
- Dystroglycans/metabolism
- Genetic Therapy/methods
- Heparan Sulfate Proteoglycans/metabolism
- Laminin/deficiency
- Laminin/genetics
- Mice
- Mice, Transgenic
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/physiopathology
- Muscular Dystrophy, Animal/metabolism
- Muscular Dystrophy, Animal/physiopathology
- Muscular Dystrophy, Animal/therapy
- Protein Structure, Tertiary/physiology
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/metabolism
- Recombinant Fusion Proteins/pharmacology
- Treatment Outcome
Collapse
Affiliation(s)
- Sarina Meinen
- Biozentrum, University of Basel, CH-4056 Basel, Switzerland
| | | | | | | | | |
Collapse
|
40
|
Peter AK, Miller G, Crosbie RH. Disrupted mechanical stability of the dystrophin-glycoprotein complex causes severe muscular dystrophy in sarcospan transgenic mice. J Cell Sci 2007; 120:996-1008. [PMID: 17311848 DOI: 10.1242/jcs.03360] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The dystrophin-glycoprotein complex spans the muscle plasma membrane and provides a mechanical linkage between laminin in the extracellular matrix and actin in the intracellular cytoskeleton. Within the dystrophin-glycoprotein complex, the sarcoglycans and sarcospan constitute a subcomplex of transmembrane proteins that stabilize α-dystroglycan, a receptor for laminin and other components of the extracellular matrix. In order to elucidate the function of sarcospan, we generated transgenic mice that overexpress sarcospan in skeletal muscle. Sarcospan transgenic mice with moderate (tenfold) levels of sarcospan overexpression exhibit a severe phenotype that is similar to mouse models of laminin-deficient congenital muscular dystrophy (MD). Sarcospan transgenic mice display severe kyphosis and die prematurely between 6 and 10 weeks of age. Histological analysis reveals that sarcospan expression causes muscle pathology marked by increased muscle fiber degeneration and/or regeneration. Sarcospan transgenic muscle does not display sarcolemma damage, which is distinct from dystrophin- and sarcoglycan-deficient muscular dystrophies. We show that sarcospan clusters the sarcoglycans into insoluble protein aggregates and causes destabilization of α-dystroglycan. Evidence is provided to demonstrate abnormal extracellular matrix assembly, which represents a probable pathological mechanism for the severe and lethal dystrophic phenotype. Taken together, these data suggest that sarcospan plays an important mechanical role in stabilizing the dystrophin-glycoprotein complex.
Collapse
Affiliation(s)
- Angela K Peter
- Department of Physiological Science, University of California, Los Angeles, CA 90095, USA
| | | | | |
Collapse
|
41
|
Sánchez del Campo LF, Nieto-Cerón S, Morote-García JC, Muñoz-Delgado E, Vidal CJ, Campoy FJ. Butyrylcholinesterase activity and molecular components in thymus of healthy and merosin-deficient Lama2dy mice. Neurochem Int 2007; 50:531-9. [PMID: 17178175 DOI: 10.1016/j.neuint.2006.11.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2006] [Revised: 10/24/2006] [Accepted: 11/02/2006] [Indexed: 01/12/2023]
Abstract
The laminin-alpha2 chain, referred to as merosin, forms part of the laminin-2 heterotrimer (alpha2beta1gamma1), which is principally expressed in the basement membrane of muscle. Nearly half of patients suffering from congenital muscular dystrophy (CMD) have abnormalities in the laminin-alpha2 chain (LAMA2) gene, and the merosin-deficient Lama2dy mouse shows CMD. The expression of merosin in thymus, the abnormalities in the gland of Lama2dy mice, and the presence of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in thymus prompted us to study the possible effects of the deficiency of merosin on thymus BuChE. We found that, while AChE activity decreased by approximately 50% in merosin-deficient thymus, the deficiency had little effect on BuChE activity. About 65% of thymus BuChE activity was extracted with a saline buffer and 30% with 1% Triton X-100. Sedimentation analyses and phenyl-agarose chromatography showed that thymus contained amphiphilic BuChE monomers (G(1)(A),44%) and dimers (G(2)(A),33%), and hydrophilic tetramers (G(4)(H),23%). Binding assays with various plant lectins revealed differences between the oligoglycans linked to BuChE tetramers and lighter components. The deficiency of merosin had no effect on the biosynthesis of thymus BuChE as judged by the lack of major changes between control and Lama2dy mice thymuses in the distribution of BuChE molecules and the level of lectin binding. The detoxifying action of BuChE, its role as a backup to AChE, and the relevance of the cholinergic dialogue between T cells and stromal cells for T lymphocyte proliferation, maturation and survival support a physiological function for BuChE in thymus.
Collapse
Affiliation(s)
- Luis F Sánchez del Campo
- Departamento de Bioquímica y Biología Molecular-A, Universidad de Murcia, E-30071 Espinardo, Murcia, Spain
| | | | | | | | | | | |
Collapse
|
42
|
Gawlik KI, Li JY, Petersén A, Durbeej M. Laminin alpha1 chain improves laminin alpha2 chain deficient peripheral neuropathy. Hum Mol Genet 2006; 15:2690-700. [PMID: 16893907 DOI: 10.1093/hmg/ddl201] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Absence of laminin alpha2 chain leads to a severe form of congenital muscular dystrophy (MDC1A) associated with peripheral neuropathy. Hence, future therapies should be aimed at alleviating both muscle and neurological dysfunctions. Pre-clinical studies in animal models have mainly focused on ameliorating the muscle phenotype. Here we show that transgenic expression of laminin alpha1 chain in muscles and the peripheral nervous system of laminin alpha2 chain deficient mice reduced muscular dystrophy and largely corrected the peripheral nerve defects. The presence of laminin alpha1 chain in the peripheral nervous system resulted in near-normal myelination, restored Schwann cell basement membranes and improved rotarod performance. In summary, we postulate that laminin alpha1 chain is an excellent substitute for laminin alpha2 chain in multiple tissues and suggest that treatment with laminin alpha1 chain may be beneficial for MDC1A in humans.
Collapse
Affiliation(s)
- Kinga I Gawlik
- Muscle Biology Unit, Division for Cell and Matrix Biology, Department of Experimental Medical Science, University of Lund, Sweden
| | | | | | | |
Collapse
|
43
|
Rooney JE, Welser JV, Dechert MA, Flintoff-Dye NL, Kaufman SJ, Burkin DJ. Severe muscular dystrophy in mice that lack dystrophin and alpha7 integrin. J Cell Sci 2006; 119:2185-95. [PMID: 16684813 DOI: 10.1242/jcs.02952] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The dystrophin glycoprotein complex links laminin in the extracellular matrix to the cell cytoskeleton. Loss of dystrophin causes Duchenne muscular dystrophy, the most common human X-chromosome-linked genetic disease. The alpha7beta1 integrin is a second transmembrane laminin receptor expressed in skeletal muscle. Mutations in the alpha7 integrin gene cause congenital myopathy in humans and mice. The alpha7beta1 integrin is increased in the skeletal muscle of Duchenne muscular dystrophy patients and mdx mice. This observation has led to the suggestion that dystrophin and alpha7beta1 integrin have complementary functional and structural roles. To test this hypothesis, we generated mice lacking both dystrophin and alpha7 integrin (mdx/alpha7(-/-)). The mdx/alpha7(-/-) mice developed early-onset muscular dystrophy and died at 2-4 weeks of age. Muscle fibers from mdx/alpha7(-/-) mice exhibited extensive loss of membrane integrity, increased centrally located nuclei and inflammatory cell infiltrate, greater necrosis and increased muscle degeneration compared to mdx or alpha7-integrin null animals. In addition, loss of dystrophin and/or alpha7 integrin resulted in altered expression of laminin-alpha2 chain. These results point to complementary roles for dystrophin and alpha7beta1 integrin in maintaining the functional integrity of skeletal muscle.
Collapse
MESH Headings
- Animals
- Antigens, CD/genetics
- Antigens, CD/metabolism
- Dystrophin/deficiency
- Dystrophin/genetics
- Dystrophin/metabolism
- Integrin alpha Chains/deficiency
- Integrin alpha Chains/genetics
- Integrin alpha Chains/metabolism
- Laminin/metabolism
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Muscle, Skeletal/ultrastructure
- Muscular Dystrophy, Duchenne/genetics
- Muscular Dystrophy, Duchenne/metabolism
- Muscular Dystrophy, Duchenne/pathology
- Regeneration
- Severity of Illness Index
- Survival Rate
Collapse
|
44
|
Miller JB, Girgenrath M. The role of apoptosis in neuromuscular diseases and prospects for anti-apoptosis therapy. Trends Mol Med 2006; 12:279-86. [PMID: 16650805 DOI: 10.1016/j.molmed.2006.04.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2006] [Revised: 03/16/2006] [Accepted: 04/13/2006] [Indexed: 12/14/2022]
Abstract
Although genetic mutations that are responsible for most of the inherited neuromuscular diseases have been identified, the molecular and cellular mechanisms that cause muscle and nerve depletion are not well understood and therapies are lacking. Histological studies of many neuromuscular diseases indicated that loss of motor-nerve and/or skeletal-muscle function might be due to excessive cell death by apoptosis. Recent studies have confirmed this possibility by showing that pathology in mouse models of amyotrophic lateral sclerosis, congenital muscular dystrophy, oculopharyngeal muscular dystrophy and collagen-VI deficiency, but not Duchenne muscular dystrophy, is significantly ameliorated by genetic or pharmacological interventions that have been designed to inhibit apoptosis. Thus, apoptosis greatly contributes to pathology in mouse models of several neuromuscular diseases, and appropriate anti-apoptosis therapy might therefore be beneficial for the corresponding human diseases.
Collapse
Affiliation(s)
- Jeffrey B Miller
- Neuromuscular Biology and Disease Group, Boston Biomedical Research Institute, 64 Grove Street, Watertown, MA 02472, USA.
| | | |
Collapse
|
45
|
Vitolo D, Ciocci L, Deriu G, Spinelli S, Cortese S, Masuelli L, Morrone S, Filice MJ, Coloni GF, Natali PG, Baroni CD. Laminin alpha2 chain-positive vessels and epidermal growth factor in lung neuroendocrine carcinoma: a model of a novel cooperative role of laminin-2 and epidermal growth factor in vessel neoplastic invasion and metastasis. THE AMERICAN JOURNAL OF PATHOLOGY 2006; 168:991-1003. [PMID: 16507913 PMCID: PMC1606521 DOI: 10.2353/ajpath.2006.041310] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Capillaries expressing the laminin alpha2 chain in basement membranes may be considered early developing vessels in normal and neoplastic human tissues. Therefore, we investigated whether up-regulation of this extracellular matrix protein favors transendothelial migration of neoplastic cells and then metastasis. In lung small and large cell neuroendocrine carcinomas, which exhibit a stronger metastatic tendency among carcinomas, laminin alpha2 chain-positive vessels were more numerous than in carcinoid tumors and supraglottis, breast, and lung non-small cell carcinomas, suggesting a direct relationship between these vessels and metastasis. In vitro studies showed that epidermal growth factor (EGF) induced a more efficient migration of the AE-2 lung neuroendocrine carcinoma cell line through the purified laminin alpha2 chain rather than through the laminin beta1 chain and fibronectin. AE-2 cells constitutively expressed all EGF receptors and the alpha6beta1 integrin, which is one of the laminin alpha2 chain receptors. EGF up-regulated alpha6beta1 expression in several tumors. In this regard, we show that EGF increased the chemo-kinetic migration of AE-2 cells through EAHY endothelial monolayers, which was inhibited by the anti-alpha6 integrin chain monoclonal antibody. These data indicate that laminin alpha2 chain and alpha6beta1 may be mutually involved in EGF-dependent migration of AE-2 cells and that laminin alpha2 chain-positive vessels may favor metastasis of EGF-dependent tumors.
Collapse
Affiliation(s)
- Domenico Vitolo
- Department of Experimental Medicine and Pathology, University of Rome La Sapienza, Rome, Italy.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Polleux F, Anton ES. Neuronal Migration in the Developing Brain. Dev Neurobiol 2006. [DOI: 10.1007/0-387-28117-7_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
47
|
Abstract
Mechanical force is generated within skeletal muscle cells by contraction of specialized myofibrillar proteins. This paper explores how the contractile force generated at the sarcomeres within an individual muscle fiber is transferred through the connective tissue to move the bones. The initial key point for transfer of the contractile force is the muscle cell membrane (sarcolemma) where force is transferred laterally to the basement membrane (specialized extracellular matrix rich in laminins) to be integrated within the connective tissue (rich in collagens) before transmission to the tendons. Connections between (1) key molecules outside the myofiber in the basement membrane to (2) molecules within the sarcolemma of the myofiber and (3) the internal cytoplasmic structures of the cytoskeleton and sarcomeres are evaluated. Disturbances to many components of this complex interactive system adversely affect skeletal muscle strength and integrity, and can result in severe muscle diseases. The mechanical aspects of these crucial linkages are discussed, with particular reference to defects in laminin-alpha2 and integrin-alpha7. Novel interventions to potentially increase muscle strength and reduce myofiber damage are mentioned, and these are also highly relevant to muscle diseases and aging muscle.
Collapse
Affiliation(s)
- M D Grounds
- School of Anatomy and Human Biology, The University of Western Australia, Perth, WA, Australia.
| | | | | |
Collapse
|
48
|
Mendell JR, Boué DR, Martin PT. The congenital muscular dystrophies: recent advances and molecular insights. Pediatr Dev Pathol 2006; 9:427-43. [PMID: 17163796 PMCID: PMC2855646 DOI: 10.2350/06-07-0127.1] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2006] [Accepted: 08/30/2006] [Indexed: 01/16/2023]
Abstract
Over the past decade, molecular understanding of the congenital muscular dystrophies (CMDs) has greatly expanded. The diseases can be classified into 3 major groups based on the affected genes and the location of their expressed protein: abnormalities of extracellular matrix proteins (LAMA2, COL6A1, COL6A2, COL6A3), abnormalities of membrane receptors for the extracellular matrix (fukutin, POMGnT1, POMT1, POMT2, FKRP, LARGE, and ITGA7), and abnormal endoplasmic reticulum protein (SEPN1). The diseases begin in the perinatal period or shortly thereafter. A specific diagnosis can be challenging because the muscle pathology is usually not distinctive. Immunostaining of muscle using a battery of antibodies can help define a disorder that will need confirmation by gene testing. In muscle diseases with overlapping pathological features, such as CMD, careful attention to the clinical clues (e.g., family history, central nervous system features) can help guide the battery of immunostains necessary to target an unequivocal diagnosis.
Collapse
Affiliation(s)
- Jerry R Mendell
- Department of Pediatrics, Columbus Children's Hospital and Research Institute and The Ohio State University, 700 Children's Drive, Columbus, OH 43205, USA.
| | | | | |
Collapse
|
49
|
van Lunteren E, Moyer M, Leahy P. Gene expression profiling of diaphragm muscle in alpha2-laminin (merosin)-deficient dy/dy dystrophic mice. Physiol Genomics 2005; 25:85-95. [PMID: 16368874 DOI: 10.1152/physiolgenomics.00226.2005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Deficiency of alpha2-laminin (merosin) underlies classical congenital muscular dystrophy in humans and dy/dy muscular dystrophy in mice and causes severe muscle dysfunction in both species. To gain greater insight into the biochemical and molecular events that link alpha2-laminin deficiency with muscle fiber necrosis, and the associated compensatory responses, gene expression profiles were characterized in diaphragm muscle from 8-wk-old dy/dy mice using oligonucleotide microarrays. Compared with age-matched normal muscle, dystrophic diaphragm was characterized by predominantly augmented gene expression, irrespective of the fold-change threshold. Among the 69 genes with at least plus or minus twofold significantly altered expression, 30 belonged to statistically overrepresented Gene Ontology (GO) biological process groups. These covered four specific themes: development including muscle development, cell motility with an emphasis on muscle contraction, defense/immune response, and cell adhesion. An additional 11 gene transcripts were assigned to more general overrepresented GO biological process groups (e.g., cellular process, organismal physiological process); the remaining 28 did not belong to any overrepresented groups. GO cellular constituent assignment resulted in the highest degree of overrepresentation in extracellular and muscle fiber locations, whereas GO molecular function assignment was most notable for various types of binding. RT-PCR was performed on 38 of 41 genes with at least plus or minus twofold significantly altered expression that were assigned to overrepresented GO biological process groups, with expression changes verified for 36 of 38 genes. These results indicate that several specific groups of genes have altered expression in response to genetic alpha2-laminin deficiency, with both similarities and differences compared with data reported for dystrophin-deficient muscular dystrophies.
Collapse
Affiliation(s)
- Erik van Lunteren
- Pulmonary and Critical Care Division, Department of Medicine, Case Western Reserve University, Cleveland Veterans Affairs Medical Center, Cleveland, Ohio, USA.
| | | | | |
Collapse
|
50
|
Sánchez del Campo L, Nieto-Cerón S, Muñoz-Delgado E, Vidal CJ, Campoy FJ. Muscular dystrophy with laminin deficiency decreases acetylcholinesterase activity in thymus of dystrophic Lama2dy mice. Chem Biol Interact 2005; 157-158:431-2. [PMID: 16429580 DOI: 10.1016/j.cbi.2005.10.092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have studied the effect of muscular dystrophy by merosin deficiency on mouse thymus acetyl- (AChE) and butyrylcholinesterase (BuChE). The organ contains AChE and BuChE activities. Merosin deficiency causes an important decrease (46%) in AChE specific activity. Thymus produces dimers, monomers and tetramers of AChE, and the three kinds of AChE mRNAs. The drop in AChE activity in dystrophic animals could affect the amount of ACh reaching cholinergic receptors in cells of lymphoid organs.
Collapse
|