1
|
Attarian S, Beloribi-Djefaflia S, Bernard R, Nguyen K, Cances C, Gavazza C, Echaniz-Laguna A, Espil C, Evangelista T, Feasson L, Audic F, Zagorda B, Milhe De Bovis V, Stojkovic T, Sole G, Salort-Campana E, Sacconi S. French National Protocol for diagnosis and care of facioscapulohumeral muscular dystrophy (FSHD). J Neurol 2024:10.1007/s00415-024-12538-3. [PMID: 38955828 DOI: 10.1007/s00415-024-12538-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 06/21/2024] [Accepted: 06/23/2024] [Indexed: 07/04/2024]
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is one of the most common genetically inherited myopathies in adults. It is characterized by incomplete penetrance and variable expressivity. Typically, FSHD patients display asymmetric weakness of facial, scapular, and humeral muscles that may progress to other muscle groups, particularly the abdominal and lower limb muscles. Early-onset patients display more severe muscle weakness and atrophy, resulting in a higher frequency of associated skeletal abnormalities. In these patients, multisystem involvement, including respiratory, ocular, and auditory, is more frequent and severe and may include the central nervous system. Adult-onset FSHD patients may also display some degree of multisystem involvement which mainly remains subclinical. In 95% of cases, FSHD patients carry a pathogenic contraction of the D4Z4 repeat units (RUs) in the subtelomeric region of chromosome 4 (4q35), which leads to the expression of DUX4 retrogene, toxic for muscles (FSHD1). Five percent of patients display the same clinical phenotype in association with a mutation in the SMCHD1 gene located in chromosome 18, inducing epigenetic modifications of the 4q D4Z4 repeated region and expression of DUX4 retrogene. This review highlights the complexities and challenges of diagnosing and managing FSHD, underscoring the importance of standardized approaches for optimal patient outcomes. It emphasizes the critical role of multidisciplinary care in addressing the diverse manifestations of FSHD across different age groups, from skeletal abnormalities in early-onset cases to the often-subclinical multisystem involvement in adults. With no current cure, the focus on alleviating symptoms and slowing disease progression through coordinated care is paramount.
Collapse
Affiliation(s)
- Shahram Attarian
- Reference Center for Neuromuscular Disorders and ALS, Timone University Hospital, Aix-Marseille University, Marseille, France.
- FILNEMUS, European Reference Network for Rare Diseases (ERN-NMD), Marseille, France.
- Marseille Medical Genetics, Aix Marseille Université-Inserm UMR_1251, 13005, Marseille, France.
| | - Sadia Beloribi-Djefaflia
- Reference Center for Neuromuscular Disorders and ALS, Timone University Hospital, Aix-Marseille University, Marseille, France
| | - Rafaelle Bernard
- Marseille Medical Genetics, Aix Marseille Université-Inserm UMR_1251, 13005, Marseille, France
| | - Karine Nguyen
- Marseille Medical Genetics, Aix Marseille Université-Inserm UMR_1251, 13005, Marseille, France
| | - Claude Cances
- Reference Center for Neuromuscular Disorders, Toulouse Children's Hospital, Toulouse, France
- Pediatric Neurology Department, Toulouse Children's Hospital, Toulouse, France
| | - Carole Gavazza
- Reference Center for Neuromuscular Disorders and ALS, Timone University Hospital, Aix-Marseille University, Marseille, France
| | - Andoni Echaniz-Laguna
- Department of Neurology, APHP, CHU de Bicêtre, Le Kremlin Bicêtre, France
- French National Reference Center for Rare Neuropathies (NNERF), Le Kremlin Bicêtre, France
- Inserm U1195, University Paris Saclay, Le Kremlin Bicêtre, France
| | - Caroline Espil
- Reference Center for Neuromuscular Disorders AOC, Children's Hospital, CHU Bordeaux, Bordeaux, France
| | - Teresinha Evangelista
- Institute of Myology, Nord/Est/Ile-de-France Neuromuscular Reference Center, Pitié-Salpêtrière Hospital, APHP, Sorbonne University, Paris, France
| | - Léonard Feasson
- Department of Clinical and Exercise Physiology, University Hospital Center of Saint-Etienne, 42000, Saint-Etienne, France
- Inter-University Laboratory of Human Movement Biology, EA 7424, Jean Monnet University, 42000, Saint-Etienne, France
| | - Frédérique Audic
- Reference Center for Neuromuscular Diseases in Children PACARARE, Neuropediatrics Department, Timone University Children's Hospital, Marseille, France
| | - Berenice Zagorda
- Department of Clinical and Exercise Physiology, University Hospital Center of Saint-Etienne, 42000, Saint-Etienne, France
| | - Virginie Milhe De Bovis
- Reference Center for Neuromuscular Disorders and ALS, Timone University Hospital, Aix-Marseille University, Marseille, France
| | - Tanya Stojkovic
- Institute of Myology, Nord/Est/Ile-de-France Neuromuscular Reference Center, Pitié-Salpêtrière Hospital, APHP, Sorbonne University, Paris, France
| | - Guilhem Sole
- Centre de Référence des Maladies Neuromusculaires AOC, FILNEMUS, Hôpital Pellegrin, CHU de Bordeaux, Bordeaux, France
| | - Emmanuelle Salort-Campana
- Reference Center for Neuromuscular Disorders and ALS, Timone University Hospital, Aix-Marseille University, Marseille, France
| | - Sabrina Sacconi
- Peripheral Nervous System and Muscle Department, Université Côte d'Azur, CHU Nice, Pasteur 2, Nice Hospital, France.
| |
Collapse
|
2
|
Jolfayi AG, Kohansal E, Ghasemi S, Naderi N, Hesami M, MozafaryBazargany M, Moghadam MH, Fazelifar AF, Maleki M, Kalayinia S. Exploring TTN variants as genetic insights into cardiomyopathy pathogenesis and potential emerging clues to molecular mechanisms in cardiomyopathies. Sci Rep 2024; 14:5313. [PMID: 38438525 PMCID: PMC10912352 DOI: 10.1038/s41598-024-56154-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 03/01/2024] [Indexed: 03/06/2024] Open
Abstract
The giant protein titin (TTN) is a sarcomeric protein that forms the myofibrillar backbone for the components of the contractile machinery which plays a crucial role in muscle disorders and cardiomyopathies. Diagnosing TTN pathogenic variants has important implications for patient management and genetic counseling. Genetic testing for TTN variants can help identify individuals at risk for developing cardiomyopathies, allowing for early intervention and personalized treatment strategies. Furthermore, identifying TTN variants can inform prognosis and guide therapeutic decisions. Deciphering the intricate genotype-phenotype correlations between TTN variants and their pathologic traits in cardiomyopathies is imperative for gene-based diagnosis, risk assessment, and personalized clinical management. With the increasing use of next-generation sequencing (NGS), a high number of variants in the TTN gene have been detected in patients with cardiomyopathies. However, not all TTN variants detected in cardiomyopathy cohorts can be assumed to be disease-causing. The interpretation of TTN variants remains challenging due to high background population variation. This narrative review aimed to comprehensively summarize current evidence on TTN variants identified in published cardiomyopathy studies and determine which specific variants are likely pathogenic contributors to cardiomyopathy development.
Collapse
Affiliation(s)
- Amir Ghaffari Jolfayi
- Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Erfan Kohansal
- Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Serwa Ghasemi
- Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Niloofar Naderi
- Cardiogenetic Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Mahshid Hesami
- Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | | | - Maryam Hosseini Moghadam
- Cardiogenetic Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Amir Farjam Fazelifar
- Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Majid Maleki
- Cardiogenetic Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Samira Kalayinia
- Cardiogenetic Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
3
|
Mohassel P, Yun P, Syeda S, Batra A, Bradley AJ, Donkervoort S, Monges S, Cohen JS, Leung DG, Munell F, Ortez C, Sánchez‐Montáñez A, Karachunski P, Brandsema J, Medne L, Chaudhry V, Tasca G, Foley AR, Udd B, Arai AE, Walter GA, Bönnemann CG. A comprehensive study of skeletal muscle imaging in FHL1-related reducing body myopathy. Ann Clin Transl Neurol 2023; 10:1442-1455. [PMID: 37483011 PMCID: PMC10424657 DOI: 10.1002/acn3.51834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 05/09/2023] [Accepted: 05/31/2023] [Indexed: 07/25/2023] Open
Abstract
OBJECTIVE FHL1-related reducing body myopathy is an ultra-rare, X-linked dominant myopathy. In this cross-sectional study, we characterize skeletal muscle ultrasound, muscle MRI, and cardiac MRI findings in FHL1-related reducing body myopathy patients. METHODS Seventeen patients (11 male, mean age 35.4, range 12-76 years) from nine independent families with FHL1-related reducing body myopathy underwent clinical evaluation, muscle ultrasound (n = 11/17), and lower extremity muscle MRI (n = 14/17), including Dixon MRI (n = 6/17). Muscle ultrasound echogenicity was graded using a modified Heckmatt scale. T1 and STIR axial images of the lower extremity muscles were evaluated for pattern and distribution of abnormalities. Quantitative analysis of intramuscular fat fraction was performed using the Dixon MRI images. Cardiac studies included electrocardiogram (n = 15/17), echocardiogram (n = 17/17), and cardiac MRI (n = 6/17). Cardiac muscle function, T1 maps, T2-weighted black blood images, and late gadolinium enhancement patterns were analyzed. RESULTS Muscle ultrasound showed a distinct pattern of increased echointensity in skeletal muscles with a nonuniform, multifocal, and "geographical" distribution, selectively involving the deeper fascicles of muscles such as biceps and tibialis anterior. Lower extremity muscle MRI showed relative sparing of gluteus maximus, rectus femoris, gracilis, and lateral gastrocnemius muscles and an asymmetric and multifocal, "geographical" pattern of T1 hyperintensity within affected muscles. Cardiac studies revealed mild and nonspecific abnormalities on electrocardiogram and echocardiogram with unremarkable cardiac MRI studies. INTERPRETATION Skeletal muscle ultrasound and muscle MRI reflect the multifocal aggregate formation in muscle in FHL1-related reducing body myopathy and are practical and informative tools that can aid in diagnosis and monitoring of disease progression.
Collapse
Affiliation(s)
- Payam Mohassel
- Neurogenetics BranchNational Institute of Neurological Disorders and StrokeBethesdaMDUSA
- Present address:
Department of NeurologyJohns Hopkins University School of MedicineBaltimoreMDUSA
| | - Pomi Yun
- Neurogenetics BranchNational Institute of Neurological Disorders and StrokeBethesdaMDUSA
| | - Safoora Syeda
- Neurogenetics BranchNational Institute of Neurological Disorders and StrokeBethesdaMDUSA
| | - Abhinandan Batra
- Department of Physical TherapyUniversity of FloridaGainesvilleFLUSA
| | | | - Sandra Donkervoort
- Neurogenetics BranchNational Institute of Neurological Disorders and StrokeBethesdaMDUSA
| | - Soledad Monges
- Servicio de NeurologíaHospital de Pediatría J.P. GarrahanBuenos AiresArgentina
| | - Julie S. Cohen
- Department of NeurologyKennedy Krieger Institute, Johns Hopkins University School of MedicineBaltimoreMDUSA
| | - Doris G. Leung
- Department of NeurologyKennedy Krieger Institute, Johns Hopkins University School of MedicineBaltimoreMDUSA
| | - Francina Munell
- Pediatric NeurologyVall d'Hebron University HospitalBarcelonaSpain
| | - Carlos Ortez
- Department of Pediatric Neurology, Neuromuscular UnitHospital Sant Joan de Déu and Institut de Recerca Sant Joan de DéuBarcelonaSpain
| | - Angel Sánchez‐Montáñez
- Pediatric NeuroradiologyHospital Universitari Vall d'Hebron, Vall d'Hebron, Autonomous University of BarcelonaBarcelonaSpain
| | | | - John Brandsema
- Division of NeurologyChildren's Hospital of PhiladelphiaPhiladelphiaPAUSA
| | - Livija Medne
- Division of NeurologyChildren's Hospital of PhiladelphiaPhiladelphiaPAUSA
| | - Vinay Chaudhry
- Department of NeurologyUniversity of North CarolinaChapel HillNCUSA
| | - Giorgio Tasca
- Unità Operativa Complessa di NeurologiaFondazione Policlinico Universitario A. Gemelli IRCCSRomeItaly
- John Walton Muscular Dystrophy Research CentreNewcastle University and Newcastle Hospitals NHS Foundation TrustsNewcastleUpon TyneUK
| | - A. Reghan Foley
- Neurogenetics BranchNational Institute of Neurological Disorders and StrokeBethesdaMDUSA
| | - Bjarne Udd
- Folkhalsan Research Center, Department of Medical GeneticsUniversity of HelsinkiHelsinkiFinland
| | - Andrew E. Arai
- Advanced Cardiovascular Imaging LaboratoryNHLBI, NIHBethesdaMDUSA
| | - Glenn A. Walter
- Department of Physiology and Functional GenomicsUniversity of FloridaGainesvilleFLUSA
| | - Carsten G. Bönnemann
- Neurogenetics BranchNational Institute of Neurological Disorders and StrokeBethesdaMDUSA
| |
Collapse
|
4
|
Aohara K, Kimura H, Takeda A, Izumiya Y, Nishino I, Itoh Y. [Sibling cases of four and a half LIM domains 1 (FHL1) myopathy who developed respiratory failure without apparent limb weakness]. Rinsho Shinkeigaku 2022; 62:726-731. [PMID: 36031379 DOI: 10.5692/clinicalneurol.cn-001761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
A 60-year-old man developed dyspnea without apparent limb weakness. He had cardiomyopathy in his 30s and was treated for chronic heart failure since 42. He was diagnosed as having four and a half LIM domains 1 (FHL1) mutation at 53 following the same diagnosis of his younger brother. He was first admitted to the cardiology department for possible worsening of chronic cardiac failure. Blood gas analysis showing respiratory acidosis prompted his treatment with a respirator. Neurological examination revealed that he had mild weakness limited to the shoulder girdle muscles and contracture at jaw, spine, elbows and ankles. Skeletal muscle CT showed truncal atrophy. He, as well as his younger brother, was diagnosed with FHL1 myopathy resulting in ventilation failure and was discharged after successful weaning from the respirator in the daytime. The present sibling cases are the first with FHL1 mutation to develop respiratory failure without limb weakness and suggest that FHL1 myopathy as a differentially diagnosis of hereditary myopathies with early respiratory failure.
Collapse
Affiliation(s)
- Kenta Aohara
- Department of Neurology, Osaka City University Graduate School of Medicine
| | - Hiroko Kimura
- Department of Neurology, Osaka City University Graduate School of Medicine
| | - Akitoshi Takeda
- Department of Neurology, Osaka City University Graduate School of Medicine
| | - Yasuhiro Izumiya
- Department of Cardiology, Osaka City University Graduate School of Medicine
| | - Ichizo Nishino
- Department of Neuromuscular Research, National Center of Neurology and Psychiatry
| | - Yoshiaki Itoh
- Department of Neurology, Osaka City University Graduate School of Medicine
| |
Collapse
|
5
|
Darki L, Jalali-Sohi A, Guzman S, Mathew AJ, Bucelli RC, Hurth KM, Beydoun SR. Reducing body myopathy associated with the LIM2 p.(His123Arg) FHL1 variant. Clin Neurol Neurosurg 2021; 207:106795. [PMID: 34273663 DOI: 10.1016/j.clineuro.2021.106795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 06/30/2021] [Accepted: 07/02/2021] [Indexed: 10/20/2022]
Abstract
Reducing body myopathy (RBM) is a rare muscle disorder, with marked presence of characteristic intracytoplasmic aggregates in affected muscle fibers. RBM is associated with FHL1 gene mutations. Clinical presentations of RBM have ranged from early fatal to adult onset progressive muscle weakness. We present herein the clinical, electrodiagnostic, and muscle biopsy findings of a 17-year-old female with progressive muscle weakness and contracture. Muscle biopsy showed atrophic fibers that contained menadione nitroblue tetrazolium (NBT) positive reducing bodies. Genetic testing revealed a variant of uncertain significance in the FHL1 gene at a position known to be pathogenic when substituted by other amino acids (p.His123Arg). This variant was later reclassified as pathogenic.
Collapse
Affiliation(s)
- Leila Darki
- Neuromuscular Division, Department of Neurology of the University of Southern California Keck School of Medicine, Los Angeles, CA, United States.
| | - Arash Jalali-Sohi
- Neuromuscular Division, Department of Neurology of the University of Southern California Keck School of Medicine, Los Angeles, CA, United States
| | - Samuel Guzman
- Department of Pathology of the University of Southern California Keck School of Medicine, Los Angeles, CA, United States
| | - Anna J Mathew
- Department of Pathology of the University of Southern California Keck School of Medicine, Los Angeles, CA, United States
| | - Robert C Bucelli
- Department of Neurology of Washington University School of Medicine in St. Louis, St. Louis, Missouri, United States
| | - Kyle M Hurth
- Department of Pathology of the University of Southern California Keck School of Medicine, Los Angeles, CA, United States
| | - Said R Beydoun
- Neuromuscular Division, Department of Neurology of the University of Southern California Keck School of Medicine, Los Angeles, CA, United States
| |
Collapse
|
6
|
Mota IA, Correia CDC, Fontana PN, Carvalho AADS. Reducing body myopathy - A new pathogenic FHL1 variant and literature review. Neuromuscul Disord 2021; 31:847-853. [PMID: 34366191 DOI: 10.1016/j.nmd.2021.03.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 03/17/2021] [Accepted: 03/31/2021] [Indexed: 11/26/2022]
Abstract
Reducing body myopathy (RBM) is a rare disease marked by progressive muscle weakness caused by a mutation in FHL1 gene. We describe a new pathogenic variant and contrasted it with 44 other cases identified in the literature. A male child presented at age 3 suffering frequent falls and progressive muscular weakness. At age 8, he was wheelchair-bound and required ventilatory support. His mother and sister died due to the same problem. Creatine kinase was 428 IU/L (<190). Muscle biopsy showed typical reducing bodies, and genetic analysis identified a novel pathogenic hemizygous variant, c.370_375del. We identified 44 previous reported cases separated in two groups: 28 cases with mean age onset 7.6 ± 5 years and 16 with 26.7 ± 4.2 years. The time for the diagnosis was shorter to younger group. The initial symptoms, rigid spine, contractures, scoliosis and axial and neck weaknesses, dysphagia, cardiac involvement, were predominant in younger group. The variant c.369C > G predominated in younger group and c.448T > C in older one. Pathogenic variants positions seemed related to severe phenotype. Most wheelchair patients belonged to younger group. The data from this compilation and our case provided a general characterization spectrum and prognosis between two groups of age onset with RBM.
Collapse
Affiliation(s)
- Isabella Araujo Mota
- Neurorehabilitation service at Hospital Universitário Lauro Wanderley, João Pessoa, Paraíba, Brazil
| | - Carolina da Cunha Correia
- Assistant Professor of Neurology at Faculdade de Ciências Medicas - Universidade de Pernambuco (UPE), Recife, Brazil
| | - Pedro Nogueira Fontana
- Post Graduate Program in Health Sciences, Faculdade de Ciências Médicas da Universidade de Pernambuco (UPE), Recife, Brazil
| | | |
Collapse
|
7
|
Williams ZJ, Velez-Irizarry D, Petersen JL, Ochala J, Finno CJ, Valberg SJ. Candidate gene expression and coding sequence variants in Warmblood horses with myofibrillar myopathy. Equine Vet J 2021; 53:306-315. [PMID: 32453872 PMCID: PMC7864122 DOI: 10.1111/evj.13286] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 03/18/2020] [Accepted: 05/02/2020] [Indexed: 12/19/2022]
Abstract
BACKGROUND Myofibrillar myopathy (MFM) of unknown aetiology has recently been identified in Warmblood (WB) horses. In humans, 16 genes have been implicated in various MFM-like disorders. OBJECTIVES To identify variants in 16 MFM candidate genes and compare allele frequencies of all variants between MFM WB and non-MFM WB and coding variants with moderate or severe predicted effects in MFM WB with publicly available data of other breeds. To compare differential gene expression and muscle fibre contractile force between MFM and non-MFM WB. STUDY DESIGN Case-control. ANIMALS 8 MFM WB, 8 non-MFM WB, 33 other WB, 32 Thoroughbreds, 80 Quarter Horses and 77 horses of other breeds in public databases. METHODS Variants were called within transcripts of 16 candidate genes using gluteal muscle mRNA sequences aligned to EquCab3.0 and allele frequencies compared by Fisher's exact test among MFM WB, non-MFM WB and public sequences across breeds. Candidate gene differential expression was determined between MFM and non-MFM WB by fitting a negative binomial generalised log-linear model per gene (false discovery rate <0.05). The maximal isometric force/cross-sectional area generated by isolated membrane-permeabilised muscle fibres was determined. RESULTS None of the 426 variants identified in 16 candidate genes were associated with MFM including 26 missense variants. Breed-specific differences existed in allele frequencies. Candidate gene differential expression and muscle fibre-specific force did not differ between MFM WB (143.1 ± 34.7 kPa) and non-MFM WB (140.2 ± 43.7 kPa) (P = .8). MAIN LIMITATIONS RNA-seq-only assays transcripts expressed in skeletal muscle. Other possible candidate genes were not evaluated. CONCLUSIONS Evidence for association of variants with a disease is essential because coding sequence variants are common in the equine genome. Variants identified in MFM candidate genes, including two coding variants offered as commercial MFM equine genetic tests, did not associate with the WB MFM phenotype.
Collapse
Affiliation(s)
- Zoë J. Williams
- Large Animal Clinical Sciences, Michigan State University, College of Veterinary Medicine, East Lansing, MI, USA
| | - Deborah Velez-Irizarry
- Large Animal Clinical Sciences, Michigan State University, College of Veterinary Medicine, East Lansing, MI, USA
| | - Jessica L. Petersen
- Department of Animal Science, University of Nebraska Lincoln, Lincoln, NE, USA
| | - Julien Ochala
- Faculty of Life Sciences and Medicine, King’s College London, London, UK
| | - Carrie J. Finno
- University of California at Davis, School of Veterinary Medicine, Davis, CA, USA
| | - Stephanie J. Valberg
- Large Animal Clinical Sciences, Michigan State University, College of Veterinary Medicine, East Lansing, MI, USA
| |
Collapse
|
8
|
Chen L, Lin HX, Yang XX, Chen DF, Dong HL, Yu H, Liu GL, Wu ZY. Clinical and genetic characteristics of Chinese patients with reducing body myopathy. Neuromuscul Disord 2021; 31:442-449. [PMID: 33846077 DOI: 10.1016/j.nmd.2021.02.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 02/04/2021] [Accepted: 02/09/2021] [Indexed: 10/22/2022]
Abstract
Reducing body myopathy (RBM) is a rare myopathy characterized by reducing bodies (RBs) in morphological presentation. The clinical manifestations of RBM present a wide clinical spectrum, varying from infantile lethal form through childhood and adult benign forms. FHL1 gene is the causative gene of RBM. To date, only 6 Chinese RBM patients have been reported. Here, we reported the clinical presentations and genetic findings of 3 Chinese RBM patients from two families. Two novel pathogenic variants, c.395G>A and c.401_402insGAC, were identified by whole exome sequencing. Furthermore, by reviewing previous studies, we revealed that most RBM patients manifested with an early onset, symmetric, progressive limb-girdle and axial muscle weakness with joint contractures, rigid spine or scoliosis except familial female patients who exhibited asymmetric benign muscle involvements. Our results provide insightful information to help better diagnose and understand the disease.
Collapse
Affiliation(s)
- Lei Chen
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China
| | - Hui-Xia Lin
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China
| | - Xin-Xia Yang
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China
| | - Dian-Fu Chen
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China
| | - Hai-Lin Dong
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China
| | - Hao Yu
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China
| | - Gong-Lu Liu
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China.
| | - Zhi-Ying Wu
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China.
| |
Collapse
|
9
|
Silva AMS, Camelo CG, Matsui-Júnior C, Mendonça RDH, Campos LM, Elias AM, Silva CA, Reed UC, Zanoteli E. Child Neurology: A Case of FHL1-Related Disease Presenting as Inflammatory Myopathy. Neurology 2020; 96:e1383-e1386. [PMID: 33361250 DOI: 10.1212/wnl.0000000000011320] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- André Macedo Serafim Silva
- From the Department of Neurology (A.M.S.S., C.G.C., C.M.-J., R.d.H.M., U.C.R., E.Z.) and Pediatric Rheumatology Unit, Instituto da Criança (L.M.C., A.M.E., C.A.S.), Hospital das Clínicas HCFMUSP, Faculdade de Medicina da Universidade de São Paulo, Brazil.
| | - Clara Gontijo Camelo
- From the Department of Neurology (A.M.S.S., C.G.C., C.M.-J., R.d.H.M., U.C.R., E.Z.) and Pediatric Rheumatology Unit, Instituto da Criança (L.M.C., A.M.E., C.A.S.), Hospital das Clínicas HCFMUSP, Faculdade de Medicina da Universidade de São Paulo, Brazil
| | - Ciro Matsui-Júnior
- From the Department of Neurology (A.M.S.S., C.G.C., C.M.-J., R.d.H.M., U.C.R., E.Z.) and Pediatric Rheumatology Unit, Instituto da Criança (L.M.C., A.M.E., C.A.S.), Hospital das Clínicas HCFMUSP, Faculdade de Medicina da Universidade de São Paulo, Brazil
| | - Rodrigo de Holanda Mendonça
- From the Department of Neurology (A.M.S.S., C.G.C., C.M.-J., R.d.H.M., U.C.R., E.Z.) and Pediatric Rheumatology Unit, Instituto da Criança (L.M.C., A.M.E., C.A.S.), Hospital das Clínicas HCFMUSP, Faculdade de Medicina da Universidade de São Paulo, Brazil
| | - Lúcia Maria Campos
- From the Department of Neurology (A.M.S.S., C.G.C., C.M.-J., R.d.H.M., U.C.R., E.Z.) and Pediatric Rheumatology Unit, Instituto da Criança (L.M.C., A.M.E., C.A.S.), Hospital das Clínicas HCFMUSP, Faculdade de Medicina da Universidade de São Paulo, Brazil
| | - Adriana Maluf Elias
- From the Department of Neurology (A.M.S.S., C.G.C., C.M.-J., R.d.H.M., U.C.R., E.Z.) and Pediatric Rheumatology Unit, Instituto da Criança (L.M.C., A.M.E., C.A.S.), Hospital das Clínicas HCFMUSP, Faculdade de Medicina da Universidade de São Paulo, Brazil
| | - Clovis Artur Silva
- From the Department of Neurology (A.M.S.S., C.G.C., C.M.-J., R.d.H.M., U.C.R., E.Z.) and Pediatric Rheumatology Unit, Instituto da Criança (L.M.C., A.M.E., C.A.S.), Hospital das Clínicas HCFMUSP, Faculdade de Medicina da Universidade de São Paulo, Brazil.
| | - Umbertina Conti Reed
- From the Department of Neurology (A.M.S.S., C.G.C., C.M.-J., R.d.H.M., U.C.R., E.Z.) and Pediatric Rheumatology Unit, Instituto da Criança (L.M.C., A.M.E., C.A.S.), Hospital das Clínicas HCFMUSP, Faculdade de Medicina da Universidade de São Paulo, Brazil
| | - Edmar Zanoteli
- From the Department of Neurology (A.M.S.S., C.G.C., C.M.-J., R.d.H.M., U.C.R., E.Z.) and Pediatric Rheumatology Unit, Instituto da Criança (L.M.C., A.M.E., C.A.S.), Hospital das Clínicas HCFMUSP, Faculdade de Medicina da Universidade de São Paulo, Brazil
| |
Collapse
|
10
|
Luo YB, Peng Y, Lu Y, Li Q, Duan H, Bi F, Yang H. Expanding the Clinico-Genetic Spectrum of Myofibrillar Myopathy: Experience From a Chinese Neuromuscular Center. Front Neurol 2020; 11:1014. [PMID: 33041974 PMCID: PMC7522348 DOI: 10.3389/fneur.2020.01014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 07/31/2020] [Indexed: 12/14/2022] Open
Abstract
Background: Myofibrillar myopathy is a group of hereditary neuromuscular disorders characterized by dissolution of myofibrils and abnormal intracellular accumulation of Z disc-related proteins. We aimed to characterize the clinical, physiological, pathohistological, and genetic features of Chinese myofibrillar myopathy patients from a single neuromuscular center. Methods: A total of 18 patients were enrolled. Demographic and clinical data were collected. Laboratory investigations, electromyography, and cardiac evaluation was performed. Routine and immunohistochemistry stainings against desmin, αB-crystallin, and BAG3 of muscle specimen were carried out. Finally, next-generation sequencing panel array for genes associated with hereditary neuromuscular disorders were performed. Results: Twelve pathogenic variants in DES, BAG3, FLNC, FHL1, and TTN were identified, of which seven were novel mutations. The novel DES c.1256C>T substitution is a high frequency mutation. The combined recessively/dominantly transmitted c.19993G>T and c.107545delG mutations in TTN gene cause a limb girdle muscular dystrophy phenotype with the classical myofibrillar myopathy histological changes. Conclusions: We report for the first time that hereditary myopathy with early respiratory failure patient can have peripheral nerve and severe spine involvement. The mutation in Ig-like domain 16 of FLNC is associated with the limb girdle type of filaminopathy, and the mutation in Ig-like domain 18 with distal myopathy type. These findings expand the phenotypic and genotypic correlation spectrum of myofibrillar myopathy.
Collapse
Affiliation(s)
- Yue-Bei Luo
- Department of Neurology, Xiangya Hospital, Central South Hospital, Changsha, China
| | - Yuyao Peng
- Department of Neurology, Xiangya Hospital, Central South Hospital, Changsha, China
| | - Yuling Lu
- Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Qiuxiang Li
- Department of Neurology, Xiangya Hospital, Central South Hospital, Changsha, China
| | - Huiqian Duan
- Department of Neurology, Xiangya Hospital, Central South Hospital, Changsha, China
| | - Fangfang Bi
- Department of Neurology, Xiangya Hospital, Central South Hospital, Changsha, China
| | - Huan Yang
- Department of Neurology, Xiangya Hospital, Central South Hospital, Changsha, China
| |
Collapse
|
11
|
Mair D, Biskup S, Kress W, Abicht A, Brück W, Zechel S, Knop KC, Koenig FB, Tey S, Nikolin S, Eggermann K, Kurth I, Ferbert A, Weis J. Differential diagnosis of vacuolar myopathies in the NGS era. Brain Pathol 2020; 30:877-896. [PMID: 32419263 PMCID: PMC8017999 DOI: 10.1111/bpa.12864] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 04/10/2020] [Accepted: 05/07/2020] [Indexed: 12/12/2022] Open
Abstract
Altered autophagy accompanied by abnormal autophagic (rimmed) vacuoles detectable by light and electron microscopy is a common denominator of many familial and sporadic non-inflammatory muscle diseases. Even in the era of next generation sequencing (NGS), late-onset vacuolar myopathies remain a diagnostic challenge. We identified 32 adult vacuolar myopathy patients from 30 unrelated families, studied their clinical, histopathological and ultrastructural characteristics and performed genetic testing in index patients and relatives using Sanger sequencing and NGS including whole exome sequencing (WES). We established a molecular genetic diagnosis in 17 patients. Pathogenic mutations were found in genes typically linked to vacuolar myopathy (GNE, LDB3/ZASP, MYOT, DES and GAA), but also in genes not regularly associated with severely altered autophagy (FKRP, DYSF, CAV3, COL6A2, GYG1 and TRIM32) and in the digenic facioscapulohumeral muscular dystrophy 2. Characteristic histopathological features including distinct patterns of myofibrillar disarray and evidence of exocytosis proved to be helpful to distinguish causes of vacuolar myopathies. Biopsy validated the pathogenicity of the novel mutations p.(Phe55*) and p.(Arg216*) in GYG1 and of the p.(Leu156Pro) TRIM32 mutation combined with compound heterozygous deletion of exon 2 of TRIM32 and expanded the phenotype of Ala93Thr-caveolinopathy and of limb-girdle muscular dystrophy 2i caused by FKRP mutation. In 15 patients no causal variants were detected by Sanger sequencing and NGS panel analysis. In 12 of these cases, WES was performed, but did not yield any definite mutation or likely candidate gene. In one of these patients with a family history of muscle weakness, the vacuolar myopathy was eventually linked to chloroquine therapy. Our study illustrates the wide phenotypic and genotypic heterogeneity of vacuolar myopathies and validates the role of histopathology in assessing the pathogenicity of novel mutations detected by NGS. In a sizable portion of vacuolar myopathy cases, it remains to be shown whether the cause is hereditary or degenerative.
Collapse
Affiliation(s)
- Dorothea Mair
- Institute of Neuropathology, RWTH Aachen University, Aachen, Germany.,Department of Neurology, Kassel School of Medicine, Klinikum Kassel, Kassel, Germany.,University of Southampton, Southampton, UK
| | - Saskia Biskup
- Centre for Genomics and Transcriptomics CeGaT, Tübingen, Germany
| | - Wolfram Kress
- Institute of Human Genetics, University Würzburg, Würzburg, Germany
| | | | - Wolfgang Brück
- Institute of Neuropathology, Göttingen University, Göttingen, Germany
| | - Sabrina Zechel
- Institute of Neuropathology, Göttingen University, Göttingen, Germany
| | | | | | - Shelisa Tey
- Institute of Neuropathology, RWTH Aachen University, Aachen, Germany
| | - Stefan Nikolin
- Institute of Neuropathology, RWTH Aachen University, Aachen, Germany
| | - Katja Eggermann
- Institute of Human Genetics, RWTH Aachen University, Aachen, Germany
| | - Ingo Kurth
- Institute of Human Genetics, RWTH Aachen University, Aachen, Germany
| | - Andreas Ferbert
- Department of Neurology, Kassel School of Medicine, Klinikum Kassel, Kassel, Germany
| | - Joachim Weis
- Institute of Neuropathology, RWTH Aachen University, Aachen, Germany
| |
Collapse
|
12
|
Lim KY, Kim HH, Sung J, Oh B, Kim K, Park S. FHL1
‐mutated reducing body myopathy. Neuropathology 2019; 40:185-190. [DOI: 10.1111/neup.12619] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 10/08/2019] [Accepted: 10/09/2019] [Indexed: 11/29/2022]
Affiliation(s)
- Ka Young Lim
- Department of Pathology Seoul National University Hospital, Seoul National University College of Medicine Seoul South Korea
| | - Hyun Hee Kim
- Department of Pathology Seoul National University Hospital, Seoul National University College of Medicine Seoul South Korea
| | - Jung‐Joon Sung
- Department of Neurology Seoul National University Hospital, Seoul National University College of Medicine Seoul South Korea
| | - Byung‐Mo Oh
- Department of Rehabilitation Medicine Seoul National University Hospital, Seoul National University College of Medicine Seoul South Korea
| | - Keewon Kim
- Department of Rehabilitation Medicine Seoul National University Hospital, Seoul National University College of Medicine Seoul South Korea
| | - Sung‐Hye Park
- Department of Pathology Seoul National University Hospital, Seoul National University College of Medicine Seoul South Korea
- Neuroscience Institute Seoul National University, College of Medicine Seoul South Korea
| |
Collapse
|
13
|
Chen T, Lu X, Shi Q, Guo J, Wang H, Wang Q, Yin X, Zhang Y, Pu C, Zhou D. FHL1-related myopathy may not be classified by reducing bodies in muscle biopsy. Neuromuscul Disord 2019; 30:165-172. [PMID: 32001145 DOI: 10.1016/j.nmd.2019.11.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 11/05/2019] [Accepted: 11/24/2019] [Indexed: 02/08/2023]
Abstract
FHL1-related myopathies, including reducing body myopathy (RBM), X-linked scapulo-axio-peroneal myopathy, rigid spine syndrome, X-linked myopathy with postural muscle atrophy (XMPMA), X-linked Emery-Dreifuss muscular dystrophy and hypertrophic cardiomyopathy, are clinically and pathologically heterogeneous disorders caused by FHL1 gene mutations. According to previous reports, the first three types are myopathies with reducing bodies observed in biopsies, and the last three are myopathies without reducing bodies. We report four FHL1-related myopathy patients, including an XMPMA patient and a RBM family with three patients. Clinical information, muscle biopsies, electromyograms and genetic testing were obtained. Muscle weakness and atrophy, spinal rigidity, and joint contracture were present in the RBM family. The XMPMA patient showed a pseudoathletic appearance with muscle weakness and atrophy, spinal rigidity and deformity. The index patient of the RBM family underwent two muscle biopsies to find reducing bodies. Interestingly, these muscle biopsies revealed reducing bodies and rimmed vacuoles not only in the RBM family but also in the XMPMA patient. Next-generation sequencing identified a reported single missense mutation c.448 C>T (p. C150R) in the RBM family and a novel mutation c.814T>C (p. S272P) in the XMPMA patient. Therefore, FHL1-related myopathies overlap substantially and may not be simply classified into subtypes depending on reducing bodies. Biopsies of additional affected muscles can aid in finding reducing bodies. We report the first XMPMA patient with a novel FHL1 mutation and reducing bodies in a muscle biopsy in China.
Collapse
Affiliation(s)
- Ting Chen
- Department of Neurology, West China Hospital, Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan 610041, China
| | - Xianghui Lu
- Department of Neurology, Chinese PLA General Hospital, 28 Fu Xing Road, Beijing 100853, China
| | - Qiang Shi
- Department of Neurology, Chinese PLA General Hospital, 28 Fu Xing Road, Beijing 100853, China
| | - Junhong Guo
- Department of Neurology, the First Hospital of Shanxi Medical University, 85 Jiefang South Road, Taiyuan 030001, China
| | - Huifang Wang
- Department of Neurology, the First Hospital of Shanxi Medical University, 85 Jiefang South Road, Taiyuan 030001, China
| | - Qian Wang
- Department of Emergency, Chinese Armed Police General Hospital, 69 Yong Ding Road, Beijing 100039, China
| | - Xi Yin
- Department of Neurology, Chinese PLA General Hospital, 28 Fu Xing Road, Beijing 100853, China
| | - Yutong Zhang
- Department of Neurology, Chinese PLA General Hospital, 28 Fu Xing Road, Beijing 100853, China
| | - Chuanqiang Pu
- Department of Neurology, Chinese PLA General Hospital, 28 Fu Xing Road, Beijing 100853, China.
| | - Dong Zhou
- Department of Neurology, West China Hospital, Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan 610041, China.
| |
Collapse
|
14
|
Gaertner-Rommel A, Tiesmeier J, Jakob T, Strickmann B, Veit G, Bachmann-Mennenga B, Paluszkiewicz L, Klingel K, Schulz U, Laser KT, Karger B, Pfeiffer H, Milting H. Molecular autopsy and family screening in a young case of sudden cardiac death reveals an unusually severe case of FHL1 related hypertrophic cardiomyopathy. Mol Genet Genomic Med 2019; 7:e841. [PMID: 31293105 PMCID: PMC6687666 DOI: 10.1002/mgg3.841] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 05/22/2019] [Accepted: 05/29/2019] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Hypertrophic cardiomyopathy (HCM) is a genetic cardiomyopathy with a prevalence of about 1:200. It is characterized by left ventricular hypertrophy, diastolic dysfunction and interstitial fibrosis; HCM might lead to sudden cardiac death (SCD) especially in the young. Due to low autopsy frequencies of sudden unexplained deaths (SUD) the true prevalence of SCD and especially of HCM among SUD remains unclear. Even in cases of proven SCD genetic testing is not a routine procedure precluding appropriate risk stratification and counseling of relatives. METHODS Here we report a case of SCD in a 19-year-old investigated by combined forensic and molecular autopsy. RESULTS During autopsy of the index-patient HCM was detected. As no other possible cause of death could be uncovered by forensic autopsy the event was classified as SCD. Molecular autopsy identified two (probably) pathogenic genetic variants in FHL1 and MYBPC3. The MYBPC3 variant had an incomplete penetrance. The FHL1 variant was a de novo mutation. We detected reduced FHL1 mRNA levels and no FHL1 protein in muscle samples suggesting nonsense-mediated mRNA decay and/or degradation of the truncated protein in the SCD victim revealing a plausible disease mechanism. CONCLUSION The identification of the genetic cause of the SCD contributed to the rational counseling of the relatives and risk assessment within the family. Furthermore our study revealed evidences for the pathomechanism of FHL1 mutations.
Collapse
Affiliation(s)
- Anna Gaertner-Rommel
- Klinikum der Ruhr-Universität Bochum, Klinik für Thorax- und Kardiovaskularchirurgie und Erich und Hanna Klessmann-Institut für Kardiovaskuläre Forschung und Entwicklung, Herz- und Diabeteszentrum NRW, Bad Oeynhausen, Germany
| | - Jens Tiesmeier
- Mühlenkreiskliniken, Krankenhaus Lübbecke-Rahden, Institut für Anästhesiologie, Intensiv- und Notfallmedizin, Medizin Campus OWL, Ruhr-Universität Bochum, Bochum, Germany
| | - Thomas Jakob
- Klinikum Herford, Universitätsklinik für Anästhesiologie, Medizin Campus OWL, Ruhr-Universität Bochum, Herford, Germany
| | | | - Gunter Veit
- Mühlenkreiskliniken, Krankenhaus Lübbecke-Rahden, Institut für Anästhesiologie, Intensiv- und Notfallmedizin, Medizin Campus OWL, Ruhr-Universität Bochum, Bochum, Germany
| | - Bernd Bachmann-Mennenga
- Mühlenkreiskliniken, Johannes Wesling Klinikum, Universitätsinstitut für Anästhesiologie, Intensiv- und Notfallmedizin, Medizin Campus OWL, Ruhr-Universität Bochum, Minden, Germany
| | - Lech Paluszkiewicz
- Klinikum der Ruhr-Universität Bochum, Klinik für Thorax- und Kardiovaskularchirurgie und Erich und Hanna Klessmann-Institut für Kardiovaskuläre Forschung und Entwicklung, Herz- und Diabeteszentrum NRW, Bad Oeynhausen, Germany
| | - Karin Klingel
- Kardiopathologie, Universitätsklinikum Tübingen, Institut für Pathologie und Neuropathologie, Tubingen, Germany
| | - Uwe Schulz
- Klinikum der Ruhr-Universität Bochum, Klinik für Thorax- und Kardiovaskularchirurgie und Erich und Hanna Klessmann-Institut für Kardiovaskuläre Forschung und Entwicklung, Herz- und Diabeteszentrum NRW, Bad Oeynhausen, Germany
| | - Kai T Laser
- Zentrum für angeborene Herzfehler, Herz- und Diabeteszentrum NRW, Klinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
| | - Bernd Karger
- Universitätsklinikum Münster, Institut für Rechtsmedizin, Münster, Germany
| | - Heidi Pfeiffer
- Universitätsklinikum Münster, Institut für Rechtsmedizin, Münster, Germany
| | - Hendrik Milting
- Klinikum der Ruhr-Universität Bochum, Klinik für Thorax- und Kardiovaskularchirurgie und Erich und Hanna Klessmann-Institut für Kardiovaskuläre Forschung und Entwicklung, Herz- und Diabeteszentrum NRW, Bad Oeynhausen, Germany
| |
Collapse
|
15
|
FHL1-related clinical, muscle MRI and genetic features in six Chinese patients with reducing body myopathy. J Hum Genet 2019; 64:919-926. [DOI: 10.1038/s10038-019-0627-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 05/14/2019] [Accepted: 05/30/2019] [Indexed: 01/21/2023]
|
16
|
Kubota A, Juanola-Falgarona M, Emmanuele V, Sanchez-Quintero MJ, Kariya S, Sera F, Homma S, Tanji K, Quinzii CM, Hirano M. Cardiomyopathy and altered integrin-actin signaling in Fhl1 mutant female mice. Hum Mol Genet 2019; 28:209-219. [PMID: 30260394 DOI: 10.1093/hmg/ddy299] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 08/14/2018] [Indexed: 12/20/2022] Open
Abstract
X-linked scapuloperoneal myopathy (X-SM), one of Four-and-a-half LIM 1 (FHL1) related diseases, is an adult-onset slowly progressive myopathy, often associated with cardiomyopathy. We previously generated a knock-in mouse model that has the same mutation (c.365 G > C, p.W122S) as human X-SM patients. The mutant male mouse developed late-onset slowly progressive myopathy without cardiomyopathy. In this study, we observed that heterozygous (Het) and homozygous (Homo) female mice did not show alterations of skeletal muscle function or histology. In contrast, 20-month-old mutant female mice showed signs of cardiomyopathy on echocardiograms with increased systolic diameter [wild-type (WT): 2.74 ± 0.22 mm, mean ± standard deviation (SD); Het: 3.13 ± 0.11 mm, P < 0.01; Homo: 3.08 ± 0.37 mm, P < 0.05) and lower fractional shortening (WT: 31.1 ± 4.4%, mean ± SD; Het: 22.7 ± 2.5%, P < 0.01; Homo: 22.4 ± 6.9%, P < 0.01]. Histological analysis of cardiac muscle revealed frequent extraordinarily large rectangular nuclei in mutant female mice that were also observed in human cardiac muscle from X-SM patients. Western blot demonstrated decreased Fhl1 protein levels in cardiac muscle, but not in skeletal muscle, of Homo mutant female mice. Proteomic analysis of cardiac muscle from 20-month-old Homo mutant female mice indicated abnormalities of the integrin signaling pathway (ISP) in association with cardiac dysfunction. The ISP dysregulation was further supported by altered levels of a subunit of the ISP downstream effectors Arpc1a in Fhl1 mutant mice and ARPC1A in X-SM patient muscles. This study reveals the first mouse model of FHL1-related cardiomyopathy and implicates ISP dysregulation in the pathogenesis of FHL1 myopathy.
Collapse
Affiliation(s)
| | | | | | | | - Shingo Kariya
- Department of Neurology, Columbia University Medical Center
| | - Fusako Sera
- Department of Cardiology, Columbia University Medical Center
| | - Shunichi Homma
- Department of Cardiology, Columbia University Medical Center
| | - Kurenai Tanji
- Department of Neurology, Columbia University Medical Center.,Department of Pathology and Cell Biology, Columbia University Medical Center
| | | | - Michio Hirano
- Department of Neurology, Columbia University Medical Center
| |
Collapse
|
17
|
Concurrent positive anti-3-hydroxy-3-methylglutaryl-coenzyme a reductase antibody with reducing body myopathy: Possible double trouble. Neuromuscul Disord 2019; 29:543-548. [PMID: 31204143 DOI: 10.1016/j.nmd.2019.05.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 05/20/2019] [Indexed: 12/23/2022]
Abstract
Anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase myopathy is less common in children but has been associated with more favorable prognosis than adult patients after immunotherapies. We report anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase antibody positivity in a 6-year-old boy with progressive muscle weakness, scoliosis, spinal rigidity, multiple joint contractures, mild left ventricular hypertrophy, and elevated serum creatine kinase. In contrast to most of previously reported pediatric anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase myopathy, he showed little response to immunotherapies. Muscle biopsy contained changes suggestive of myofiber necrosis and regeneration and reducing bodies. The diagnosis of reducing body myopathy was later confirmed by reported c.368A>G (p.His123Arg) mutation in the FHL1 gene. Although the level of association between these two conditions is still inconclusive, this is the first report of concurrent positive anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase antibody with reducing body myopathy emphasizing the possibility of co-occurrence of immune mediated necrotizing myopathy and muscular dystrophy and importance of comprehensive diagnostic investigations in unusual cases.
Collapse
|
18
|
Malfatti E. Miopatías congénitas. REVISTA MÉDICA CLÍNICA LAS CONDES 2018. [DOI: 10.1016/j.rmclc.2018.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
19
|
Fichna JP, Maruszak A, Żekanowski C. Myofibrillar myopathy in the genomic context. J Appl Genet 2018; 59:431-439. [PMID: 30203143 DOI: 10.1007/s13353-018-0463-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 08/30/2018] [Indexed: 12/31/2022]
Abstract
Myofibrillar myopathy (MFM) is a group of inherited muscular disorders characterized by myofibril dissolution and abnormal accumulation of degradation products. The diagnosis of muscular disorders based on clinical presentation is difficult due to phenotypic heterogeneity and overlapping symptoms. In addition, precise diagnosis does not always explain the disease etiopathology or the highly variable clinical course even among patients diagnosed with the same type of myopathy. The advent of high-throughput next-generation sequencing (NGS) has provided a successful and cost-effective strategy for identification of novel causative genes in myopathies, including MFM. So far, pathogenic mutations associated with MFM phenotype, including atypical MFM-like cases, have been identified in 17 genes: DES, CRYAB, MYOT, ZASP, FLNC, BAG3, FHL1, TTN, DNAJB6, PLEC, LMNA, ACTA1, HSPB8, KY, PYROXD1, and SQSTM + TIA1 (digenic). Most of these genes are also associated with other forms of muscle diseases. In addition, in many MFM patients, numerous genomic variants in muscle-related genes have been identified. The various myopathies and muscular dystrophies seem to form a single disease continuum; therefore, gene identification in one disease impacts the genetic etiology of the others. In this review, we describe the heterogeneity of the MFM genetic background focusing on the role of rare variants, the importance of whole genome sequencing in the identification of novel disease-associated mutations, and the emerging concept of variant load as the basis of the phenotypic heterogeneity.
Collapse
Affiliation(s)
- Jakub Piotr Fichna
- Department of Neurodegenerative Disorders, Mossakowski Medical Research Centre, Polish Academy of Sciences, 5 Pawinskiego St., 02-106, Warsaw, Poland.
| | - Aleksandra Maruszak
- Department of Neurodegenerative Disorders, Mossakowski Medical Research Centre, Polish Academy of Sciences, 5 Pawinskiego St., 02-106, Warsaw, Poland
| | - Cezary Żekanowski
- Department of Neurodegenerative Disorders, Mossakowski Medical Research Centre, Polish Academy of Sciences, 5 Pawinskiego St., 02-106, Warsaw, Poland
| |
Collapse
|
20
|
Ding J, Cong YF, Liu B, Miao J, Wang L. Aberrant Protein Turn-Over Associated With Myofibrillar Disorganization in FHL1 Knockout Mice. Front Genet 2018; 9:273. [PMID: 30083183 PMCID: PMC6065255 DOI: 10.3389/fgene.2018.00273] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 07/04/2018] [Indexed: 12/12/2022] Open
Abstract
Mutations in the FHL1 gene, and FHL1 protein deletion, are associated with rare hereditary myopathies and cardiomyopathies. FHL1-null mice develop age-dependent myopathy and increased autophagic activity. However, the molecular pathway involved in contractile function and increased autophagic activity in the FHL1-null mouse has not yet been fully elucidated. In this study, FHL1 protein was knocked out in mice using Transcription Activator-like Effector Nucleases (TALENs) and the IRS1-FOXO1/mTOR signaling pathway was investigated in skeletal muscles and heart. TALEN constructs caused targeted mutations in 30% of newborn mice; these mutations caused a deletion of 1–13 base pairs which blocked synthesis of the full-length FHL1 protein. Furthermore, 2.5-month old FHL1-null male mice were not prone to global muscular fatigue when compared with WT littermates, but histological analysis and ultrastructural analysis by transmission electron microscopy confirmed the presence of myofibrillar disorganization and the accumulation of autophagosome or autolysosome-like structures in FHL1-null mice. Moreover, autophagy and mitophagy were both activated in FHL1 KO mice and the degradation of autophagic lysosomes was impeded. Enhanced autophagic activity in FHL1 KO mice was induced by FOXO1 up-regulation and protein synthesis was increased via mTOR. The cytoskeletal proteins, MYBPC2 and LDB3, were involved in the formation of pathological changes in FHL1 KO mice. Markers of early differentiation (MEF2C and MYOD1) and terminal differentiation (total MYH) were both up-regulated in tibialis anterior (TA) muscles in FHL1 KO mice. The number of type I and type II fibers increased in FHL1-null TA muscles, but the number of type| | b, and type | | d fibers were both reduced in FHL1-null TA muscles. The results obtained from the heart were consistent with those from the skeletal muscle and indicated autophagic activation by FOXO1 and an increase in protein synthesis via mTOR also occurred in the heart tissue of FHL1 knockout mice. In conclusion, aberrant protein turn-over associated with myofibrillar disorganization in FHL1 knockout mice. the up-regulation of FOXO1 was associated with enhanced autophagic activity and pathological changes in the muscle fibers of FHL1 KO mice. These results indicated that autophagy activated by FOXO1 is a promising therapeutic target for hereditary myopathies and cardiomyopathies induced by FHL1.
Collapse
Affiliation(s)
- Jingjing Ding
- Medical Research Center of Shengjing Hospital, China Medical University, Shenyang, China
| | - Yan Fei Cong
- Medical Research Center of Shengjing Hospital, China Medical University, Shenyang, China
| | - Bo Liu
- Medical Research Center of Shengjing Hospital, China Medical University, Shenyang, China
| | - Jianing Miao
- Medical Research Center of Shengjing Hospital, China Medical University, Shenyang, China
| | - Lili Wang
- Medical Research Center of Shengjing Hospital, China Medical University, Shenyang, China
| |
Collapse
|
21
|
Keßler M, Kieltsch A, Kayvanpour E, Katus H, Schoser B, Schessl J, Just S, Rottbauer W. A zebrafish model for FHL1-opathy reveals loss-of-function effects of human FHL1 mutations. Neuromuscul Disord 2018; 28:521-531. [DOI: 10.1016/j.nmd.2018.03.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 11/27/2017] [Accepted: 03/01/2018] [Indexed: 11/16/2022]
|
22
|
Ehsan M, Jiang H, L Thomson K, Gehmlich K. When signalling goes wrong: pathogenic variants in structural and signalling proteins causing cardiomyopathies. J Muscle Res Cell Motil 2017; 38:303-316. [PMID: 29119312 PMCID: PMC5742121 DOI: 10.1007/s10974-017-9487-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 10/28/2017] [Indexed: 12/20/2022]
Abstract
Cardiomyopathies are a diverse group of cardiac disorders with distinct phenotypes, depending on the proteins and pathways affected. A substantial proportion of cardiomyopathies are inherited and those will be the focus of this review article. With the wide application of high-throughput sequencing in the practice of clinical genetics, the roles of novel genes in cardiomyopathies are recognised. Here, we focus on a subgroup of cardiomyopathy genes [TTN, FHL1, CSRP3, FLNC and PLN, coding for Titin, Four and a Half LIM domain 1, Muscle LIM Protein, Filamin C and Phospholamban, respectively], which, despite their diverse biological functions, all have important signalling functions in the heart, suggesting that disturbances in signalling networks can contribute to cardiomyopathies.
Collapse
Affiliation(s)
- Mehroz Ehsan
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, UK
| | - He Jiang
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Kate L Thomson
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Katja Gehmlich
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, UK.
| |
Collapse
|
23
|
Sato K, Kimura M, Sugiyama K, Nishikawa M, Okano Y, Nagaoka H, Nagase T, Kitade Y, Ueda H. Four-and-a-half LIM Domains 1 (FHL1) Protein Interacts with the Rho Guanine Nucleotide Exchange Factor PLEKHG2/FLJ00018 and Regulates Cell Morphogenesis. J Biol Chem 2016; 291:25227-25238. [PMID: 27765816 DOI: 10.1074/jbc.m116.759571] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 10/20/2016] [Indexed: 11/06/2022] Open
Abstract
PLEKHG2/FLJ00018 is a Gβγ-dependent guanine nucleotide exchange factor for the small GTPases Rac and Cdc42 and has been shown to mediate the signaling pathways leading to actin cytoskeleton reorganization. Here we showed that the zinc finger domain-containing protein four-and-a-half LIM domains 1 (FHL1) acts as a novel interaction partner of PLEKHG2 by the yeast two-hybrid system. Among the isoforms of FHL1 (i.e. FHL1A, FHL1B, and FHL1C), FHL1A and FHL1B interacted with PLEKHG2. We found that there was an FHL1-binding region at amino acids 58-150 of PLEKHG2. The overexpression of FHL1A but not FHL1B enhanced the PLEKHG2-induced serum response element-dependent gene transcription. The co-expression of FHL1A and Gβγ synergistically enhanced the PLEKHG2-induced serum response element-dependent gene transcription. Increased transcription activity was decreased by FHL1A knock-out with the CRISPR/Cas9 system. Compared with PLEKHG2-expressing cells, the number and length of finger-like protrusions were increased in PLEKHG2-, Gβγ-, and FHL1A-expressing cells. Our results provide evidence that FHL1A interacts with PLEKHG2 and regulates cell morphological change through the activity of PLEKHG2.
Collapse
Affiliation(s)
- Katsuya Sato
- From the United Graduate School of Drug Discovery and Medical Information Sciences and
| | - Masashi Kimura
- the Department of Molecular Pathobiochemistry, Gifu University Graduate School of Medicine, Yanagido 1-1, Gifu 501-1193, Japan
| | - Kazue Sugiyama
- From the United Graduate School of Drug Discovery and Medical Information Sciences and
| | - Masashi Nishikawa
- From the United Graduate School of Drug Discovery and Medical Information Sciences and
| | - Yukio Okano
- the Department of Molecular Pathobiochemistry, Gifu University Graduate School of Medicine, Yanagido 1-1, Gifu 501-1193, Japan
| | - Hitoshi Nagaoka
- the Department of Molecular Pathobiochemistry, Gifu University Graduate School of Medicine, Yanagido 1-1, Gifu 501-1193, Japan
| | - Takahiro Nagase
- the Kazusa DNA Research Institute, 2-6-7 Kazusa-kamatari, Kisarazu, Chiba 292-0818, Japan, and
| | - Yukio Kitade
- From the United Graduate School of Drug Discovery and Medical Information Sciences and.,the Department of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, Yanagido 1-1, Gifu 501-1193, Japan
| | - Hiroshi Ueda
- From the United Graduate School of Drug Discovery and Medical Information Sciences and .,the Department of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, Yanagido 1-1, Gifu 501-1193, Japan
| |
Collapse
|
24
|
Exome sequencing identifies variants in two genes encoding the LIM-proteins NRAP and FHL1 in an Italian patient with BAG3 myofibrillar myopathy. J Muscle Res Cell Motil 2016; 37:101-15. [PMID: 27443559 PMCID: PMC5010835 DOI: 10.1007/s10974-016-9451-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 07/09/2016] [Indexed: 11/06/2022]
Abstract
Myofibrillar myopathies (MFMs) are genetically heterogeneous dystrophies characterized by the disintegration of Z-disks and myofibrils and are associated with mutations in genes encoding Z-disk or Z-disk-related proteins. The c.626 C > T (p.P209L) mutation in the BAG3 gene has been described as causative of a subtype of MFM. We report a sporadic case of a 26-year-old Italian woman, affected by MFM with axonal neuropathy, cardiomyopathy, rigid spine, who carries the c.626 C > T mutation in the BAG3 gene. The patient and her non-consanguineous healthy parents and brother were studied with whole exome sequencing (WES) to further investigate the genetic basis of this complex phenotype. In the patient, we found that the BAG3 mutation is associated with variants in the NRAP and FHL1 genes that encode muscle-specific, LIM domain containing proteins. Quantitative real time PCR, immunohistochemistry and Western blot analysis of the patient’s muscular biopsy showed the absence of NRAP expression and FHL1 accumulation in aggregates in the affected skeletal muscle tissue. Molecular dynamic analysis of the mutated FHL1 domain showed a modification in its surface charge, which could affect its capability to bind its target proteins. To our knowledge this is the first study reporting, in a BAG3 MFM, the simultaneous presence of genetic variants in the BAG3 and FHL1 genes (previously described as independently associated with MFMs) and linking the NRAP gene to MFM for the first time.
Collapse
|
25
|
Willis T, Wood C, Hudson J, Polvikoski T, Barresi R, Lochmüller H, Bushby K, Straub V. Muscle hypertrophy as the presenting sign in a patient with a completeFHL1deletion. Clin Genet 2016; 90:166-70. [DOI: 10.1111/cge.12695] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 11/02/2015] [Accepted: 11/12/2015] [Indexed: 12/19/2022]
Affiliation(s)
- T.A. Willis
- John Walton Muscular Dystrophy Research Centre; Institute of Genetic Medicine; Newcastle upon Tyne UK
| | - C.L. Wood
- John Walton Muscular Dystrophy Research Centre; Institute of Genetic Medicine; Newcastle upon Tyne UK
| | - J. Hudson
- John Walton Muscular Dystrophy Research Centre; Institute of Genetic Medicine; Newcastle upon Tyne UK
| | - T. Polvikoski
- Institute of Neuroscience; Newcastle University; Newcastle upon Tyne UK
| | - R. Barresi
- John Walton Muscular Dystrophy Research Centre; Institute of Genetic Medicine; Newcastle upon Tyne UK
- Rare Diseases Advisory Group Service for Neuromuscular Diseases; Muscle Immunoanalysis Unit; Newcastle upon Tyne UK
| | - H. Lochmüller
- John Walton Muscular Dystrophy Research Centre; Institute of Genetic Medicine; Newcastle upon Tyne UK
| | - K. Bushby
- John Walton Muscular Dystrophy Research Centre; Institute of Genetic Medicine; Newcastle upon Tyne UK
| | - V. Straub
- John Walton Muscular Dystrophy Research Centre; Institute of Genetic Medicine; Newcastle upon Tyne UK
| |
Collapse
|
26
|
Albrecht I, Wick C, Hallgren Å, Tjärnlund A, Nagaraju K, Andrade F, Thompson K, Coley W, Phadke A, Diaz-Gallo LM, Bottai M, Nennesmo I, Chemin K, Herrath J, Johansson K, Wikberg A, Ytterberg AJ, Zubarev RA, Danielsson O, Krystufkova O, Vencovsky J, Landegren N, Wahren-Herlenius M, Padyukov L, Kämpe O, Lundberg IE. Development of autoantibodies against muscle-specific FHL1 in severe inflammatory myopathies. J Clin Invest 2015; 125:4612-24. [PMID: 26551678 DOI: 10.1172/jci81031] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 09/25/2015] [Indexed: 11/17/2022] Open
Abstract
Mutations of the gene encoding four-and-a-half LIM domain 1 (FHL1) are the causative factor of several X-linked hereditary myopathies that are collectively termed FHL1-related myopathies. These disorders are characterized by severe muscle dysfunction and damage. Here, we have shown that patients with idiopathic inflammatory myopathies (IIMs) develop autoimmunity to FHL1, which is a muscle-specific protein. Anti-FHL1 autoantibodies were detected in 25% of IIM patients, while patients with other autoimmune diseases or muscular dystrophies were largely anti-FHL1 negative. Anti-FHL1 reactivity was predictive for muscle atrophy, dysphagia, pronounced muscle fiber damage, and vasculitis. FHL1 showed an altered expression pattern, with focal accumulation in the muscle fibers of autoantibody-positive patients compared with a homogeneous expression in anti-FHL1-negative patients and healthy controls. We determined that FHL1 is a target of the cytotoxic protease granzyme B, indicating that the generation of FHL1 fragments may initiate FHL1 autoimmunity. Moreover, immunization of myositis-prone mice with FHL1 aggravated muscle weakness and increased mortality, suggesting a direct link between anti-FHL1 responses and muscle damage. Together, our findings provide evidence that FHL1 may be involved in the pathogenesis not only of genetic FHL1-related myopathies but also of autoimmune IIM. Importantly, these results indicate that anti-FHL1 autoantibodies in peripheral blood have promising potential as a biomarker to identify a subset of severe IIM.
Collapse
|
27
|
D'Arcy C, Kanellakis V, Forbes R, Wilding B, McGrath M, Howell K, Ryan M, McLean C. X-linked Recessive Distal Myopathy With Hypertrophic Cardiomyopathy Caused by a Novel Mutation in the FHL1 Gene. J Child Neurol 2015; 30:1211-7. [PMID: 25246303 DOI: 10.1177/0883073814549807] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 08/11/2014] [Indexed: 11/16/2022]
Abstract
FHL1 gene mutations are associated with reducing body myopathy, X-linked myopathy with postural muscle atrophy, scapuloperoneal myopathy, Emery-Dreifuss muscular dystrophy, and isolated hypertrophic cardiomyopathy. We describe a boy with a family history consistent with X-linked distal myopathy/cardiomyopathy. The boy first presented at age 14 years and was found to have distal wasting and weakness. Echocardiogram revealed hypertrophic cardiomyopathy. Muscle biopsy showed a vacuolar pathology with no reducing bodies. Sequencing of FHL1 revealed a novel hemizygous c.764G>C missense mutation in exon 8. This is the first report of a predominantly distal myopathy with hypertrophic cardiomyopathy occurring secondary to an FHL1 mutation.
Collapse
Affiliation(s)
- Colleen D'Arcy
- Faculty of Medicine, Nursing and Health Sciences, Monash University, Victoria, Australia Department of Anatomical Pathology, The Alfred Hospital, Victoria, Australia
| | - Voula Kanellakis
- Applied Genetics Diagnostics, University of Melbourne, Melbourne, Australia
| | - Robin Forbes
- Victorian Clinical Genetics Service, Royal Children's Hospital, Victoria, Australia
| | - Brendan Wilding
- Department of Biochemistry and Molecular Biology, Monash University, Victoria, Australia
| | - Meagan McGrath
- Department of Biochemistry and Molecular Biology, Monash University, Victoria, Australia
| | - Katherine Howell
- Children's Neurosciences Centre, Royal Children's Hospital, Victoria, Australia
| | - Monique Ryan
- Children's Neurosciences Centre, Royal Children's Hospital, Victoria, Australia
| | - Catriona McLean
- Faculty of Medicine, Nursing and Health Sciences, Monash University, Victoria, Australia Department of Anatomical Pathology, The Alfred Hospital, Victoria, Australia
| |
Collapse
|
28
|
Jackson S, Schaefer J, Meinhardt M, Reichmann H. Mitochondrial abnormalities in the myofibrillar myopathies. Eur J Neurol 2015. [DOI: 10.1111/ene.12814] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- S. Jackson
- Department of Neurology; Technische Universität Dresden; Dresden Germany
| | - J. Schaefer
- Department of Neurology; Technische Universität Dresden; Dresden Germany
| | - M. Meinhardt
- Department of Pathology; Technische Universität Dresden; Dresden Germany
| | - H. Reichmann
- Department of Neurology; Technische Universität Dresden; Dresden Germany
| |
Collapse
|
29
|
The sarcomeric M-region: a molecular command center for diverse cellular processes. BIOMED RESEARCH INTERNATIONAL 2015; 2015:714197. [PMID: 25961035 PMCID: PMC4413555 DOI: 10.1155/2015/714197] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 02/08/2015] [Indexed: 02/07/2023]
Abstract
The sarcomeric M-region anchors thick filaments and withstands the mechanical stress of contractions by deformation, thus enabling distribution of physiological forces along the length of thick filaments. While the role of the M-region in supporting myofibrillar structure and contractility is well established, its role in mediating additional cellular processes has only recently started to emerge. As such, M-region is the hub of key protein players contributing to cytoskeletal remodeling, signal transduction, mechanosensing, metabolism, and proteasomal degradation. Mutations in genes encoding M-region related proteins lead to development of severe and lethal cardiac and skeletal myopathies affecting mankind. Herein, we describe the main cellular processes taking place at the M-region, other than thick filament assembly, and discuss human myopathies associated with mutant or truncated M-region proteins.
Collapse
|
30
|
Hunter JM, Kiefer J, Balak CD, Jooma S, Ahearn ME, Hall JG, Baumbach-Reardon L. Review of X-linked syndromes with arthrogryposis or early contractures-aid to diagnosis and pathway identification. Am J Med Genet A 2015; 167A:931-73. [DOI: 10.1002/ajmg.a.36934] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 12/05/2014] [Indexed: 02/03/2023]
Affiliation(s)
- Jesse M. Hunter
- Integrated Functional Cancer Genomics; Translational Genomics Research Institute; Phoenix Arizona
| | - Jeff Kiefer
- Knowledge Mining; Translational Genomics Research Institute; Phoenix Arizona
| | - Christopher D. Balak
- Integrated Functional Cancer Genomics; Translational Genomics Research Institute; Phoenix Arizona
| | - Sonya Jooma
- Integrated Functional Cancer Genomics; Translational Genomics Research Institute; Phoenix Arizona
| | - Mary Ellen Ahearn
- Integrated Functional Cancer Genomics; Translational Genomics Research Institute; Phoenix Arizona
| | - Judith G. Hall
- Departments of Medical Genetics and Pediatrics; University of British Columbia and BC Children's Hospital Vancouver; British Columbia Canada
| | - Lisa Baumbach-Reardon
- Integrated Functional Cancer Genomics; Translational Genomics Research Institute; Phoenix Arizona
| |
Collapse
|
31
|
Narayanaswami P, Weiss M, Selcen D, David W, Raynor E, Carter G, Wicklund M, Barohn RJ, Ensrud E, Griggs RC, Gronseth G, Amato AA. Evidence-based guideline summary: diagnosis and treatment of limb-girdle and distal dystrophies: report of the guideline development subcommittee of the American Academy of Neurology and the practice issues review panel of the American Association of Neuromuscular & Electrodiagnostic Medicine. Neurology 2014; 83:1453-63. [PMID: 25313375 DOI: 10.1212/wnl.0000000000000892] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
OBJECTIVE To review the current evidence and make practice recommendations regarding the diagnosis and treatment of limb-girdle muscular dystrophies (LGMDs). METHODS Systematic review and practice recommendation development using the American Academy of Neurology guideline development process. RESULTS Most LGMDs are rare, with estimated prevalences ranging from 0.07 per 100,000 to 0.43 per 100,000. The frequency of some muscular dystrophies varies based on the ethnic background of the population studied. Some LGMD subtypes have distinguishing features, including pattern of muscle involvement, cardiac abnormalities, extramuscular involvement, and muscle biopsy findings. The few published therapeutic trials were not designed to establish clinical efficacy of any treatment. PRINCIPAL RECOMMENDATIONS For patients with suspected muscular dystrophy, clinicians should use a clinical approach to guide genetic diagnosis based on clinical phenotype, inheritance pattern, and associated manifestations (Level B). Clinicians should refer newly diagnosed patients with an LGMD subtype and high risk of cardiac complications for cardiology evaluation even if they are asymptomatic from a cardiac standpoint (Level B). In patients with LGMD with a known high risk of respiratory failure, clinicians should obtain periodic pulmonary function testing (Level B). Clinicians should refer patients with muscular dystrophy to a clinic that has access to multiple specialties designed specifically to care for patients with neuromuscular disorders (Level B). Clinicians should not offer patients with LGMD gene therapy, myoblast transplantation, neutralizing antibody to myostatin, or growth hormone outside of a research study designed to determine efficacy and safety of the treatment (Level R). Detailed results and recommendations are available on the Neurology® Web site at Neurology.org.
Collapse
Affiliation(s)
- Pushpa Narayanaswami
- From the Department of Neurology (P.N., E.R.), Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA; the Department of Neurology (M.W.), University of Washington Medical Center, Seattle; the Department of Neurology (D.S.), Mayo Clinic, Rochester, MN; the Department of Neurology (W.D.), Massachusetts General Hospital/Harvard Medical School, Boston; St Luke's Rehabilitation Institute (G.C.), Spokane, WA; the Department of Neurology (M.W.), Penn State Hershey Medical Center, PA; the Department of Neurology (R.J.B., G.G.), University of Kansas Medical Center, Kansas City; the Neuromuscular Center (E.E.), Boston VA Medical Center, MA; the Department of Neurology (R.C.G.), University of Rochester Medical Center, NY; and the Department of Neurology (E.E., A.A.A.), Brigham and Women's Hospital/Harvard Medical School, Boston, MA
| | - Michael Weiss
- From the Department of Neurology (P.N., E.R.), Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA; the Department of Neurology (M.W.), University of Washington Medical Center, Seattle; the Department of Neurology (D.S.), Mayo Clinic, Rochester, MN; the Department of Neurology (W.D.), Massachusetts General Hospital/Harvard Medical School, Boston; St Luke's Rehabilitation Institute (G.C.), Spokane, WA; the Department of Neurology (M.W.), Penn State Hershey Medical Center, PA; the Department of Neurology (R.J.B., G.G.), University of Kansas Medical Center, Kansas City; the Neuromuscular Center (E.E.), Boston VA Medical Center, MA; the Department of Neurology (R.C.G.), University of Rochester Medical Center, NY; and the Department of Neurology (E.E., A.A.A.), Brigham and Women's Hospital/Harvard Medical School, Boston, MA
| | - Duygu Selcen
- From the Department of Neurology (P.N., E.R.), Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA; the Department of Neurology (M.W.), University of Washington Medical Center, Seattle; the Department of Neurology (D.S.), Mayo Clinic, Rochester, MN; the Department of Neurology (W.D.), Massachusetts General Hospital/Harvard Medical School, Boston; St Luke's Rehabilitation Institute (G.C.), Spokane, WA; the Department of Neurology (M.W.), Penn State Hershey Medical Center, PA; the Department of Neurology (R.J.B., G.G.), University of Kansas Medical Center, Kansas City; the Neuromuscular Center (E.E.), Boston VA Medical Center, MA; the Department of Neurology (R.C.G.), University of Rochester Medical Center, NY; and the Department of Neurology (E.E., A.A.A.), Brigham and Women's Hospital/Harvard Medical School, Boston, MA
| | - William David
- From the Department of Neurology (P.N., E.R.), Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA; the Department of Neurology (M.W.), University of Washington Medical Center, Seattle; the Department of Neurology (D.S.), Mayo Clinic, Rochester, MN; the Department of Neurology (W.D.), Massachusetts General Hospital/Harvard Medical School, Boston; St Luke's Rehabilitation Institute (G.C.), Spokane, WA; the Department of Neurology (M.W.), Penn State Hershey Medical Center, PA; the Department of Neurology (R.J.B., G.G.), University of Kansas Medical Center, Kansas City; the Neuromuscular Center (E.E.), Boston VA Medical Center, MA; the Department of Neurology (R.C.G.), University of Rochester Medical Center, NY; and the Department of Neurology (E.E., A.A.A.), Brigham and Women's Hospital/Harvard Medical School, Boston, MA
| | - Elizabeth Raynor
- From the Department of Neurology (P.N., E.R.), Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA; the Department of Neurology (M.W.), University of Washington Medical Center, Seattle; the Department of Neurology (D.S.), Mayo Clinic, Rochester, MN; the Department of Neurology (W.D.), Massachusetts General Hospital/Harvard Medical School, Boston; St Luke's Rehabilitation Institute (G.C.), Spokane, WA; the Department of Neurology (M.W.), Penn State Hershey Medical Center, PA; the Department of Neurology (R.J.B., G.G.), University of Kansas Medical Center, Kansas City; the Neuromuscular Center (E.E.), Boston VA Medical Center, MA; the Department of Neurology (R.C.G.), University of Rochester Medical Center, NY; and the Department of Neurology (E.E., A.A.A.), Brigham and Women's Hospital/Harvard Medical School, Boston, MA
| | - Gregory Carter
- From the Department of Neurology (P.N., E.R.), Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA; the Department of Neurology (M.W.), University of Washington Medical Center, Seattle; the Department of Neurology (D.S.), Mayo Clinic, Rochester, MN; the Department of Neurology (W.D.), Massachusetts General Hospital/Harvard Medical School, Boston; St Luke's Rehabilitation Institute (G.C.), Spokane, WA; the Department of Neurology (M.W.), Penn State Hershey Medical Center, PA; the Department of Neurology (R.J.B., G.G.), University of Kansas Medical Center, Kansas City; the Neuromuscular Center (E.E.), Boston VA Medical Center, MA; the Department of Neurology (R.C.G.), University of Rochester Medical Center, NY; and the Department of Neurology (E.E., A.A.A.), Brigham and Women's Hospital/Harvard Medical School, Boston, MA
| | - Matthew Wicklund
- From the Department of Neurology (P.N., E.R.), Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA; the Department of Neurology (M.W.), University of Washington Medical Center, Seattle; the Department of Neurology (D.S.), Mayo Clinic, Rochester, MN; the Department of Neurology (W.D.), Massachusetts General Hospital/Harvard Medical School, Boston; St Luke's Rehabilitation Institute (G.C.), Spokane, WA; the Department of Neurology (M.W.), Penn State Hershey Medical Center, PA; the Department of Neurology (R.J.B., G.G.), University of Kansas Medical Center, Kansas City; the Neuromuscular Center (E.E.), Boston VA Medical Center, MA; the Department of Neurology (R.C.G.), University of Rochester Medical Center, NY; and the Department of Neurology (E.E., A.A.A.), Brigham and Women's Hospital/Harvard Medical School, Boston, MA
| | - Richard J Barohn
- From the Department of Neurology (P.N., E.R.), Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA; the Department of Neurology (M.W.), University of Washington Medical Center, Seattle; the Department of Neurology (D.S.), Mayo Clinic, Rochester, MN; the Department of Neurology (W.D.), Massachusetts General Hospital/Harvard Medical School, Boston; St Luke's Rehabilitation Institute (G.C.), Spokane, WA; the Department of Neurology (M.W.), Penn State Hershey Medical Center, PA; the Department of Neurology (R.J.B., G.G.), University of Kansas Medical Center, Kansas City; the Neuromuscular Center (E.E.), Boston VA Medical Center, MA; the Department of Neurology (R.C.G.), University of Rochester Medical Center, NY; and the Department of Neurology (E.E., A.A.A.), Brigham and Women's Hospital/Harvard Medical School, Boston, MA
| | - Erik Ensrud
- From the Department of Neurology (P.N., E.R.), Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA; the Department of Neurology (M.W.), University of Washington Medical Center, Seattle; the Department of Neurology (D.S.), Mayo Clinic, Rochester, MN; the Department of Neurology (W.D.), Massachusetts General Hospital/Harvard Medical School, Boston; St Luke's Rehabilitation Institute (G.C.), Spokane, WA; the Department of Neurology (M.W.), Penn State Hershey Medical Center, PA; the Department of Neurology (R.J.B., G.G.), University of Kansas Medical Center, Kansas City; the Neuromuscular Center (E.E.), Boston VA Medical Center, MA; the Department of Neurology (R.C.G.), University of Rochester Medical Center, NY; and the Department of Neurology (E.E., A.A.A.), Brigham and Women's Hospital/Harvard Medical School, Boston, MA
| | - Robert C Griggs
- From the Department of Neurology (P.N., E.R.), Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA; the Department of Neurology (M.W.), University of Washington Medical Center, Seattle; the Department of Neurology (D.S.), Mayo Clinic, Rochester, MN; the Department of Neurology (W.D.), Massachusetts General Hospital/Harvard Medical School, Boston; St Luke's Rehabilitation Institute (G.C.), Spokane, WA; the Department of Neurology (M.W.), Penn State Hershey Medical Center, PA; the Department of Neurology (R.J.B., G.G.), University of Kansas Medical Center, Kansas City; the Neuromuscular Center (E.E.), Boston VA Medical Center, MA; the Department of Neurology (R.C.G.), University of Rochester Medical Center, NY; and the Department of Neurology (E.E., A.A.A.), Brigham and Women's Hospital/Harvard Medical School, Boston, MA
| | - Gary Gronseth
- From the Department of Neurology (P.N., E.R.), Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA; the Department of Neurology (M.W.), University of Washington Medical Center, Seattle; the Department of Neurology (D.S.), Mayo Clinic, Rochester, MN; the Department of Neurology (W.D.), Massachusetts General Hospital/Harvard Medical School, Boston; St Luke's Rehabilitation Institute (G.C.), Spokane, WA; the Department of Neurology (M.W.), Penn State Hershey Medical Center, PA; the Department of Neurology (R.J.B., G.G.), University of Kansas Medical Center, Kansas City; the Neuromuscular Center (E.E.), Boston VA Medical Center, MA; the Department of Neurology (R.C.G.), University of Rochester Medical Center, NY; and the Department of Neurology (E.E., A.A.A.), Brigham and Women's Hospital/Harvard Medical School, Boston, MA
| | - Anthony A Amato
- From the Department of Neurology (P.N., E.R.), Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA; the Department of Neurology (M.W.), University of Washington Medical Center, Seattle; the Department of Neurology (D.S.), Mayo Clinic, Rochester, MN; the Department of Neurology (W.D.), Massachusetts General Hospital/Harvard Medical School, Boston; St Luke's Rehabilitation Institute (G.C.), Spokane, WA; the Department of Neurology (M.W.), Penn State Hershey Medical Center, PA; the Department of Neurology (R.J.B., G.G.), University of Kansas Medical Center, Kansas City; the Neuromuscular Center (E.E.), Boston VA Medical Center, MA; the Department of Neurology (R.C.G.), University of Rochester Medical Center, NY; and the Department of Neurology (E.E., A.A.A.), Brigham and Women's Hospital/Harvard Medical School, Boston, MA
| | | | | |
Collapse
|
32
|
Emmanuele V, Kubota A, Garcia-Diaz B, Garone C, Akman HO, Sánchez-Gutiérrez D, Escudero LM, Kariya S, Homma S, Tanji K, Quinzii CM, Hirano M. Fhl1 W122S causes loss of protein function and late-onset mild myopathy. Hum Mol Genet 2014; 24:714-26. [PMID: 25274776 DOI: 10.1093/hmg/ddu490] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
A member of the four-and-a-half-LIM (FHL) domain protein family, FHL1, is highly expressed in human adult skeletal and cardiac muscle. Mutations in FHL1 have been associated with diverse X-linked muscle diseases: scapuloperoneal (SP) myopathy, reducing body myopathy, X-linked myopathy with postural muscle atrophy, rigid spine syndrome (RSS) and Emery-Dreifuss muscular dystrophy. In 2008, we identified a missense mutation in the second LIM domain of FHL1 (c.365 G>C, p.W122S) in a family with SP myopathy. We generated a knock-in mouse model harboring the c.365 G>C Fhl1 mutation and investigated the effects of this mutation at three time points (3-5 months, 7-10 months and 18-20 months) in hemizygous male and heterozygous female mice. Survival was comparable in mutant and wild-type animals. We observed decreased forelimb strength and exercise capacity in adult hemizygous male mice starting from 7 to 10 months of age. Western blot analysis showed absence of Fhl1 in muscle at later stages. Thus, adult hemizygous male, but not heterozygous female, mice showed a slowly progressive phenotype similar to human patients with late-onset muscle weakness. In contrast to SP myopathy patients with the FHL1 W122S mutation, mutant mice did not manifest cytoplasmic inclusions (reducing bodies) in muscle. Because muscle weakness was evident prior to loss of Fhl1 protein and without reducing bodies, our findings indicate that loss of function is responsible for the myopathy in the Fhl1 W122S knock-in mice.
Collapse
Affiliation(s)
- Valentina Emmanuele
- Department of Neurology Pediatric Clinic, Istituto di Ricovero e Cura a Carattere Scientifico G. Gaslini, University of Genoa, Genoa 16100, Italy and
| | | | | | | | | | - Daniel Sánchez-Gutiérrez
- Departamento de Biología Celular, Universidad de Sevilla and Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universdad de Sevilla, 41013 Seville, Spain
| | - Luis M Escudero
- Departamento de Biología Celular, Universidad de Sevilla and Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universdad de Sevilla, 41013 Seville, Spain
| | | | - Shunichi Homma
- Department of Medicine, Columbia University Medical Center, New York, NY 10032, USA
| | - Kurenai Tanji
- Department of Neurology Department of Pathology and Cell Biology
| | | | | |
Collapse
|
33
|
Sabatelli P, Castagnaro S, Tagliavini F, Chrisam M, Sardone F, Demay L, Richard P, Santi S, Maraldi NM, Merlini L, Sandri M, Bonaldo P. Aggresome-Autophagy Involvement in a Sarcopenic Patient with Rigid Spine Syndrome and a p.C150R Mutation in FHL1 Gene. Front Aging Neurosci 2014; 6:215. [PMID: 25191266 PMCID: PMC4137286 DOI: 10.3389/fnagi.2014.00215] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Accepted: 08/04/2014] [Indexed: 11/13/2022] Open
Abstract
The four-and-half LIM domain protein 1 (FHL1) is highly expressed in skeletal and cardiac muscle. Mutations of the FHL1 gene have been associated with diverse chronic myopathies including reducing body myopathy, rigid spine syndrome (RSS), and Emery–Dreifuss muscular dystrophy. We investigated a family with a mutation (p.C150R) in the second LIM domain of FHL1. In this family, a brother and a sister were affected by RSS, and their mother had mild lower limbs weakness. The 34-year-old female had an early and progressive rigidity of the cervical spine and severe respiratory insufficiency. Muscle mass evaluated by DXA was markedly reduced, while fat mass was increased to 40%. CT scan showed an almost complete substitution of muscle by fibro-adipose tissue. Muscle biopsy showed accumulation of FHL1 throughout the cytoplasm and around myonuclei into multiprotein aggregates with aggresome/autophagy features as indicated by ubiquitin, p62, and LC3 labeling. DNA deposits, not associated with nuclear lamina components and histones, were also detected in the aggregates, suggesting nuclear degradation. Ultrastructural analysis showed the presence of dysmorphic nuclei, accumulation of tubulofilamentous and granular material, and perinuclear accumulation of autophagic vacuoles. These data point to involvement of the aggresome–autophagy pathway in the pathophysiological mechanism underlying the muscle pathology of FHL1 C150R mutation.
Collapse
Affiliation(s)
- Patrizia Sabatelli
- Institute of Molecular Genetics, CNR-National Research Council of Italy , Bologna , Italy ; SC Laboratory of Musculoskeletal Cell Biology, Rizzoli Orthopedic Institute , Bologna , Italy
| | - Silvia Castagnaro
- Department of Molecular Medicine, University of Padova , Padova , Italy
| | - Francesca Tagliavini
- Institute of Molecular Genetics, CNR-National Research Council of Italy , Bologna , Italy ; SC Laboratory of Musculoskeletal Cell Biology, Rizzoli Orthopedic Institute , Bologna , Italy
| | - Martina Chrisam
- Department of Molecular Medicine, University of Padova , Padova , Italy
| | - Francesca Sardone
- Institute of Molecular Genetics, CNR-National Research Council of Italy , Bologna , Italy ; SC Laboratory of Musculoskeletal Cell Biology, Rizzoli Orthopedic Institute , Bologna , Italy
| | - Laurence Demay
- UF Cardiogénétique et Myogénétique, Service de Biochimie Métabolique, Groupe Hospitalier Pitié-Salpêtrière , Paris , France
| | - Pascale Richard
- UF Cardiogénétique et Myogénétique, Centre de Génétique, Hôpitaux Universitaires de la Pitié Salpêtrière , Paris , France
| | - Spartaco Santi
- Institute of Molecular Genetics, CNR-National Research Council of Italy , Bologna , Italy ; SC Laboratory of Musculoskeletal Cell Biology, Rizzoli Orthopedic Institute , Bologna , Italy
| | - Nadir M Maraldi
- Institute of Molecular Genetics, CNR-National Research Council of Italy , Bologna , Italy
| | - Luciano Merlini
- SC Laboratory of Musculoskeletal Cell Biology, Rizzoli Orthopedic Institute , Bologna , Italy
| | - Marco Sandri
- Dulbecco Telethon Institute, Venetian Institute of Molecular Medicine , Padova , Italy ; Department of Biomedical Science, University of Padova , Padova , Italy
| | - Paolo Bonaldo
- Department of Molecular Medicine, University of Padova , Padova , Italy
| |
Collapse
|
34
|
A case of adult-onset reducing body myopathy presenting a novel clinical feature, asymmetrical involvement of the sternocleidomastoid and trapezius muscles. J Neurol Sci 2014; 343:206-10. [DOI: 10.1016/j.jns.2014.05.056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Revised: 05/22/2014] [Accepted: 05/24/2014] [Indexed: 11/21/2022]
|
35
|
Abstract
PURPOSE OF REVIEW Myofibrillar myopathies (MFMs) are a heterogeneous group of skeletal and cardiac muscle diseases. In this review, we highlight recent discoveries of new genes and disease mechanisms involved in this group of disorders. RECENT FINDINGS The advent of next-generation sequencing technology, laser microdissection and mass spectrometry-based proteomics has facilitated the discovery of new MFM causative genes and pathomechanisms. New mutations have also been discovered in 'older' genes, helping to find a classification niche for MFM-linked disorders showing variant phenotypes. Cell transfection experiments using primary cultured myoblasts and newer animal models provide insights into the pathogenesis of MFMs. SUMMARY An increasing number of genes are involved in the causation of variant subtypes of MFM. The application of modern technologies in combination with classical histopathological and ultrastructural studies is helping to establish the molecular diagnosis and reach a better understanding of the pathogenic mechanisms of each MFM subtype, thus putting an emphasis on the development of specific means for prevention and therapy of these incapacitating and frequently fatal diseases.
Collapse
|
36
|
Bertrand AT, Bönnemann CG, Bonne G. 199th ENMC international workshop: FHL1 related myopathies, June 7-9, 2013, Naarden, The Netherlands. Neuromuscul Disord 2014; 24:453-62. [PMID: 24613424 DOI: 10.1016/j.nmd.2014.02.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 02/04/2014] [Indexed: 02/04/2023]
Affiliation(s)
- Anne T Bertrand
- Inserm, U974, Paris F-75013, France; Sorbonne Universités, UPMC Univ Paris 06, Myology Center of Research, UM76; CNRS FRE 3617, Institut de Myologie, Paris F-75013, France
| | - Carsten G Bönnemann
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA
| | - Gisèle Bonne
- Inserm, U974, Paris F-75013, France; Sorbonne Universités, UPMC Univ Paris 06, Myology Center of Research, UM76; CNRS FRE 3617, Institut de Myologie, Paris F-75013, France; AP-HP, Groupe Hospitalier Pitié-Salpêtrière, U.F. Cardiogénétique et Myogénétique Moléculaire, Service de Biochimie Métabolique, Paris F-75013, France.
| | | |
Collapse
|
37
|
Wilding BR, McGrath MJ, Bonne G, Mitchell CA. FHL1 mutations that cause clinically distinct human myopathies form protein aggregates and impair myoblast differentiation. J Cell Sci 2014; 127:2269-81. [DOI: 10.1242/jcs.140905] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
FHL1 mutations cause several clinically heterogeneous myopathies including Reducing Body Myopathy (RBM), Scapuloperoneal Myopathy (SPM) and X-Linked Myopathy with Postural Muscle Atrophy (XMPMA). The molecular mechanisms underlying the pathogenesis of FHL1 myopathies are unknown. Protein aggregates designated “Reducing Bodies” (RBs) containing mutant FHL1 are detected in RBM muscle but not several other FHL1 myopathies. Here RBM, SPM and XMPMA FHL1 mutants were expressed in C2C12 cells and showed equivalent protein expression to wild-type FHL1 and formed aggregates positive for the RB stain Menadione-NBT, analogous to RBM muscle aggregates. However HCM and EDMD FHL1 mutants generally exhibited reduced expression. Wild-type FHL1 promotes myoblast differentiation however RBM, SPM and XMPMA mutations impaired differentiation, consistent with loss-of-normal function. Furthermore, SPM and XMPMA mutants retarded myotube formation relative to vector control consistent with a dominant-negative/toxic function. Mutant FHL1 myotube formation was partially rescued by expression of the FHL1-binding partner constitutively-active NFATc1. This is the first study to show FHL1 mutations identified in several clinically distinct myopathies lead to similar protein aggregation and impaired myotube formation suggesting a common pathogenic mechanism despite heterogenous clinical features.
Collapse
|
38
|
Skeletal muscle biopsy analysis in reducing body myopathy and other FHL1-related disorders. J Neuropathol Exp Neurol 2013; 72:833-45. [PMID: 23965743 DOI: 10.1097/nen.0b013e3182a23506] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
FHL1 mutations have been associated with various disorders that include reducing body myopathy (RBM), Emery-Dreifuss-like muscular dystrophy, isolated hypertrophic cardiomyopathy, and some overlapping conditions. We report a detailed histochemical, immunohistochemical, electron microscopic, and immunoelectron microscopic analyses of muscle biopsies from 18 patients carrying mutations in FHL1: 14 RBM patients (Group 1), 3 Emery-Dreifuss muscular dystrophy patients (Group 2), and 1 patient with hypertrophic cardiomyopathy and muscular hypertrophy (Group 2). Group 1 muscle biopsies consistently showed RBs associated with cytoplasmic bodies. The RBs showed prominent FHL1 immunoreactivity whereas desmin, αB-crystallin, and myotilin immunoreactivity surrounded RBs. By electron microscopy, RBs were composed of electron-dense tubulofilamentous material that seemed to spread progressively between the myofibrils and around myonuclei. By immunoelectron microscopy, FHL1 protein was found exclusively inside RBs. Group 2 biopsies showed mild dystrophic abnormalities without RBs; only minor nonspecific myofibrillar abnormalities were observed under electron microscopy. Molecular analysis revealed missense mutations in the second FHL1 LIM domain in Group 1 patients and ins/del or missense mutations within the fourth FHL1 LIM domain in Group 2 patients. Our findings expand the morphologic features of RBM, clearly demonstrate the localization of FHL1 in RBs, and further illustrate major morphologic differences among different FHL1-related myopathies.
Collapse
|
39
|
Abstract
Electron microscopy is an essential component of myopathology, both in diagnostics and research of neuromuscular diseases. Although recently reduced in the diagnostic armamentarium, it has greatly been expanded to mouse models in research. Mostly it is descriptive, but a few additional techniques in combination with transmission electron microscopy have been employed. Foremost among them is immunoelectron microscopy, which assists in guiding molecular analysis in hereditary conditions, but may be vital in diagnostics of certain acquired entities, e.g., undulating tubules in dermatomyositis and in those congenital myopathies where genes and mutations remain to be identified, as in cylindrical spirals myopathy and hexagonal crystalloid-body myopathy.
Collapse
Affiliation(s)
- Hans H Goebel
- Department of Neuropathology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany and
| | | |
Collapse
|
40
|
Domenighetti AA, Chu PH, Wu T, Sheikh F, Gokhin DS, Guo LT, Cui Z, Peter AK, Christodoulou DC, Parfenov MG, Gorham JM, Li DY, Banerjee I, Lai X, Witzmann FA, Seidman CE, Seidman JG, Gomes AV, Shelton GD, Lieber RL, Chen J. Loss of FHL1 induces an age-dependent skeletal muscle myopathy associated with myofibrillar and intermyofibrillar disorganization in mice. Hum Mol Genet 2013; 23:209-25. [PMID: 23975679 DOI: 10.1093/hmg/ddt412] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Recent human genetic studies have provided evidences that sporadic or inherited missense mutations in four-and-a-half LIM domain protein 1 (FHL1), resulting in alterations in FHL1 protein expression, are associated with rare congenital myopathies, including reducing body myopathy and Emery-Dreifuss muscular dystrophy. However, it remains to be clarified whether mutations in FHL1 cause skeletal muscle remodeling owing to gain- or loss of FHL1 function. In this study, we used FHL1-null mice lacking global FHL1 expression to evaluate loss-of-function effects on skeletal muscle homeostasis. Histological and functional analyses of soleus, tibialis anterior and sternohyoideus muscles demonstrated that FHL1-null mice develop an age-dependent myopathy associated with myofibrillar and intermyofibrillar (mitochondrial and sarcoplasmic reticulum) disorganization, impaired muscle oxidative capacity and increased autophagic activity. A longitudinal study established decreased survival rates in FHL1-null mice, associated with age-dependent impairment of muscle contractile function and a significantly lower exercise capacity. Analysis of primary myoblasts isolated from FHL1-null muscles demonstrated early muscle fiber differentiation and maturation defects, which could be rescued by re-expression of the FHL1A isoform, highlighting that FHL1A is necessary for proper muscle fiber differentiation and maturation in vitro. Overall, our data show that loss of FHL1 function leads to myopathy in vivo and suggest that loss of function of FHL1 may be one of the mechanisms underlying muscle dystrophy in patients with FHL1 mutations.
Collapse
|
41
|
Eymard B, Ferreiro A, Ben Yaou R, Stojkovic T. Muscle diseases with prominent joint contractures: Main entities and diagnostic strategy. Rev Neurol (Paris) 2013; 169:546-63. [DOI: 10.1016/j.neurol.2013.07.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 07/23/2013] [Accepted: 07/24/2013] [Indexed: 01/13/2023]
|
42
|
Feldkirchner S, Walter MC, Müller S, Kubny C, Krause S, Kress W, Hanisch FG, Schoser B, Schessl J. Proteomic characterization of aggregate components in an intrafamilial variable FHL1-associated myopathy. Neuromuscul Disord 2013; 23:418-26. [DOI: 10.1016/j.nmd.2013.02.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 02/09/2013] [Indexed: 11/28/2022]
|
43
|
Dysregulation of FHL1 spliceforms due to an indel mutation produces an Emery-Dreifuss muscular dystrophy plus phenotype. Neurogenetics 2013; 14:113-21. [PMID: 23456229 DOI: 10.1007/s10048-013-0359-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 02/19/2013] [Indexed: 10/27/2022]
Abstract
Emery-Dreifuss muscular dystrophy (EDMD) is characterised by early-onset joint contractures, progressive muscular weakness and wasting and late-onset cardiac disease. The more common X-linked recessive form of EDMD is caused by mutations in either EMD (encoding emerin) or FHL1 (encoding four and a half LIM domains 1), while mutations in LMNA (encoding lamin A/C), SYNE1 (encoding nesprin-1) and SYNE2 (encoding nesprin-2) lead to autosomal dominant forms of the condition. Here, we identify a three-generation family with an extended EDMD phenotype due to a novel indel mutation in FHL1 that differentially affects the relative expression of the three known transcript isoforms produced from this locus. The additional phenotypic manifestations in this family-proportionate short stature, facial dysmorphism, pulmonary valvular stenosis, thoracic scoliosis, brachydactyly, pectus deformities and genital abnormalities-are reminiscent of phenotypes seen with dysregulated Ras-mitogen-activated protein kinase (RAS-MAPK) signalling [Noonan syndrome (NS) and related disorders]. The misexpression of FHL1 transcripts precipitated by this mutation, together with the role of FHL1 in the regulation of RAS-MAPK signalling, suggests that this mutation confers a complex phenotype through both gain- and loss-of-function mechanisms. This indel mutation in FHL1 broadens the spectrum of FHL1-related disorders and implicates it in the pathogenesis of NS spectrum disorders.
Collapse
|
44
|
Schreckenbach T, Henn W, Kress W, Roos A, Maschke M, Feiden W, Dillmann U, Schulz JB, Weis J, Claeys KG. NovelFHL1mutation in a family with reducing body myopathy. Muscle Nerve 2012; 47:127-34. [DOI: 10.1002/mus.23500] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/11/2012] [Indexed: 11/06/2022]
|
45
|
Feldkirchner S, Schessl J, Müller S, Schoser B, Hanisch FG. Patient-specific protein aggregates in myofibrillar myopathies: laser microdissection and differential proteomics for identification of plaque components. Proteomics 2012; 12:3598-609. [PMID: 23044792 DOI: 10.1002/pmic.201100559] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Revised: 09/17/2012] [Accepted: 10/01/2012] [Indexed: 01/15/2023]
Abstract
Myofibrillar myopathies (MFMs) are histopathologically characterized by desmin-positive protein aggregates and myofibrillar degeneration. While about half of all MFM are caused by mutations in genes encoding sarcomeric and extra-sarcomeric proteins (desmin, filamin C, plectin, VCP, FHL1, ZASP, myotilin, αB-crystallin, and BAG3), the other half of these diseases is due to still unresolved gene defects. The present study aims at the proteomic characterization of pathological protein aggregates in skeletal muscle biopsies from patients with MFM-causing gene mutations. The technical strategy is based on the dissection of plaque versus plaque-free tissue areas from the same individual patient by laser dissection microscopy, filter-aided sample preparation, iTRAQ-labeling, and analysis on the peptide level using offline nano-LC and MALDI-TOF-TOF MS/MS for protein identification and quantification. The outlined workflow overcomes limitations of merely qualitative analyses, which cannot discriminate contaminating nonaggregated proteins. Dependent on the MFM causing mutation, different sets of proteins were revealed as genuine (accumulated) plaque components in independent technical replicates: (i) αB-crystallin, desmin, filamin A/C, myotilin, PRAF3, RTN2, SQSTM, XIRP1, and XIRP2 (patient with defined MFM mutation distinct from FHL1) or (ii) desmin, FHL1, filamin A/C, KBTBD10, NRAP, SQSTM, RL40, XIRP1, and XIRP2 (patient with FHL1 mutation). The results from differential proteomics indicate that plaques from different patients exhibit protein compositions with partial overlap, on the one hand, and mutation-dependent protein contents on the other. The FHL1 mutation-specific pattern was validated for four patients with respect to desmin, SQSTM, and FHL1 by immunohistochemistry.
Collapse
Affiliation(s)
- Sarah Feldkirchner
- Department of Neurology, Friedrich-Baur-Institute, Ludwig-Maximilians-University, Munich, Germany
| | | | | | | | | |
Collapse
|
46
|
Komagamine T, Kawai M, Kokubun N, Miyatake S, Ogata K, Hayashi YK, Nishino I, Hirata K. Selective muscle involvement in a family affected by a second LIM domain mutation of fhl1: An imaging study using computed tomography. J Neurol Sci 2012; 318:163-7. [DOI: 10.1016/j.jns.2012.04.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Revised: 04/04/2012] [Accepted: 04/04/2012] [Indexed: 01/30/2023]
|
47
|
Finsterer J. Stroke and Stroke-like Episodes in Muscle Disease. Open Neurol J 2012; 6:26-36. [PMID: 22715346 PMCID: PMC3377871 DOI: 10.2174/1874205x01206010026] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Revised: 04/02/2012] [Accepted: 04/11/2012] [Indexed: 12/13/2022] Open
Abstract
Background: Though not obvious at a first glance, myopathies may be associated with ischemic stroke. Stroke-like episodes resemble ischemic stroke only to some extent but are a unique feature of certain mitochondrial disorders with a pathogenesis at variance from that of ischemic stroke. Only limited data are available about ischemic stroke in pri-mary myopathies and the management of stroke-like episodes in mitochondrial disorders. This review aims to summarize and discuss current knowledge about stroke in myopathies and to delineate stroke-like episodes from ischemic stroke. Methods: Literature review via PubMED using the search terms “stroke”, “cerebrovascular”, “ischemic event”, “stroke-like episode”, “stroke-mimic”, “mitochondrial disorder”. Results: Stroke in myopathies is most frequently cardioembolic due to atrial fibrillation or atrial flutter, dilated cardio-myopathy, or left-ventricular hypertrabeculation (noncompaction). The second most frequent cause of stroke in myopathies is angiopathy from atherosclerosis or vasculitis, which may be a feature of inflammatory myopathies. Athero-sclerosis may either result from classical risk factors, such as diabetes, arterial hypertension, hyperlpidemia, or smoking, associated with muscle disease, or may be an inherent feature of a mitochondrial disorder. In case of severe heart failure from cardiomyopathy as a manifestation of muscle disease low flow infarcts may occur. Thrombophilic stroke has been described in polymyositis and dermatomyositis in association with anti-phospholipid syndrome. Stroke-like episodes occur particularly in mitochondrial encephalopathy, lactacidosis and stroke-likeepisode syndrome but rarely also in Leigh-syndrome and other mitochondrial disorders. Stroke-like episodes are at variance from ischemic stroke, pathogenically, clinically and on imaging. They may be the manifestation of a vascular, metabolic or epileptic process and present with predominantly vasogenic but also cytotoxic edema on MRI. Differentiation between ischemic stroke and stroke-like episodes is essential in terms of management and prognosis. Management of ischemic stroke in patients with myopathy is not at variance from the treatment of ischemic stroke in non-myopathic patients. There is no standardized treatment of stroke-like episodes but there is increasing evidence that these patients profit from the administration of L-arginine and conse-quent antiepileptic treatment if associated with seizure activity. Conclusions: Ischemic stroke may be a complication of myopathy and needs to be delineated from stroke-like episodes, which are unique to mitochondrial disorders, particularly mitochondrial encephalopathy, lactacidosis and stroke-likeepisode syndrome. Ischemic stroke in myopathies is most frequently cardioembolic and treatment is not at variance from non-myopathic ischemic stroke. Treatment of stroke-like episodes is not standardized but seems to respond to L-arginine and adequate antiepileptic treatment.
Collapse
Affiliation(s)
- Josef Finsterer
- Krankenanstalt Rudolfstiftung, Vienna, Danube University Krems, Austria
| |
Collapse
|
48
|
Friedrich FW, Wilding BR, Reischmann S, Crocini C, Lang P, Charron P, Müller OJ, McGrath MJ, Vollert I, Hansen A, Linke WA, Hengstenberg C, Bonne G, Morner S, Wichter T, Madeira H, Arbustini E, Eschenhagen T, Mitchell CA, Isnard R, Carrier L. Evidence for FHL1 as a novel disease gene for isolated hypertrophic cardiomyopathy. Hum Mol Genet 2012; 21:3237-54. [PMID: 22523091 DOI: 10.1093/hmg/dds157] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is characterized by asymmetric left ventricular hypertrophy, diastolic dysfunction and myocardial disarray. HCM is caused by mutations in sarcomeric genes, but in >40% of patients, the mutation is not yet identified. We hypothesized that FHL1, encoding four-and-a-half-LIM domains 1, could be another disease gene since it has been shown to cause distinct myopathies, sometimes associated with cardiomyopathy. We evaluated 121 HCM patients, devoid of a mutation in known disease genes. We identified three novel variants in FHL1 (c.134delA/K45Sfs, c.459C>A/C153X and c.827G>C/C276S). Whereas the c.459C>A variant was associated with muscle weakness in some patients, the c.134delA and c.827G>C variants were associated with isolated HCM. Gene transfer of the latter variants in C2C12 myoblasts and cardiac myocytes revealed reduced levels of FHL1 mutant proteins, which could be rescued by proteasome inhibition. Contractility measurements after adeno-associated virus transduction in rat-engineered heart tissue (EHT) showed: (i) higher and lower forces of contraction with K45Sfs and C276S, respectively, and (ii) prolonged contraction and relaxation with both mutants. All mutants except one activated the fetal hypertrophic gene program in EHT. In conclusion, this study provides evidence for FHL1 to be a novel gene for isolated HCM. These data, together with previous findings of proteasome impairment in HCM, suggest that FHL1 mutant proteins may act as poison peptides, leading to hypertrophy, diastolic dysfunction and/or altered contractility, all features of HCM.
Collapse
Affiliation(s)
- Felix W Friedrich
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Abstract
The LINC (linker of nucleoskeleton and cytoskeleton) complex is a proposed mechanical link tethering the nucleo- and cyto-skeleton via the NE (nuclear envelope). The LINC components emerin, lamin A/C, SUN1, SUN2, nesprin-1 and nesprin-2 interact with each other at the NE and also with other binding partners including actin filaments and B-type lamins. Besides the mechanostructural functions, the LINC complex is also involved in signalling pathways and gene regulation. Emerin was the first LINC component associated with a human disease, namely EDMD (Emery-Dreifuss muscular dystrophy). Later on, other components of the LINC complex, such as lamins A/C and small isoforms of nesprin-1 and nesprin-2, were found to be associated with EDMD, reflecting a genetic heterogeneity that has not been resolved so far. Only approximately 46% of the EDMD patients can be linked to genes of LINC and non-LINC components, pointing to further genes involved in the pathology of EDMD. Obvious candidates are the LINC proteins SUN1 and SUN2. Recently, screening of binding partners of LINC components as candidates identified LUMA (TMEM43), encoding a binding partner of emerin and lamins, as a gene involved in atypical EDMD. Nevertheless, such mutations contribute only to a very small fraction of EDMD patients. EDMD-causing mutations in STA/EMD (encoding emerin) that disrupt emerin binding to Btf (Bcl-2-associated transcription factor), GCL (germ cell-less) and BAF (barrier to autointegration factor) provide the first glimpses into LINC being involved in gene regulation and thus opening new avenues for functional studies. Thus the association of LINC with human disease provides tools for understanding its functions within the cell.
Collapse
|
50
|
Abstract
During the past 2 years, considerable progress in the field of four and a half LIM domain protein 1 (FHL1)-related myopathies has led to the identification of a growing number of FHL1 mutations. This genetic progress has uncovered crucial pathophysiological concepts, thus redefining clinical phenotypes. Important new characterizations include 4 distinct human myopathies: reducing body myopathy, X-linked myopathy with postural muscle atrophy, Emery-Dreifuss muscular dystrophy, and scapuloperoneal myopathy. Additionally, FHL1 mutations have been discovered in rigid spine syndrome and in a single family with contractures, rigid spine, and cardiomyopathy. In this review, we focus on the clinical phenotypes, which we correlate with the novel genetic and histological findings encountered within FHL1-related myopathies. This correlation will frequently lead to a considerably expanded clinical spectrum associated with a given FHL1 mutation.
Collapse
|