title: HANAC Col4a1 Mutation in Mice Leads to Skeletal Muscle Alterations due to a Primary Vascular Defect.
abstract: Collagen IV is a major component of basement membranes (BMs). The α1(IV) chain, encoded by the COL4A1 gene, is expressed ubiquitously and associates with the α2(IV) chain to form the α1α1α2(IV) heterotrimer. Several COL4A1 mutations affecting a conformational domain containing integrin-binding sites are responsible for the systemic syndrome of hereditary angiopathy, nephropathy, aneurysms, and cramps (HANAC). To analyze the pathophysiology of HANAC, Col4a1 mutant mice bearing the p.Gly498Val mutation were generated. Analysis of the skeletal muscles of Col4a1G498Vmutant animals showed morphologic characteristics of a muscular dystrophy phenotype with myofiber atrophy, centronucleation, focal inflammatory infiltrates, and fibrosis. Abnormal ultrastructural aspects of muscle BMs was associated with reduced extracellular secretion of the mutant α1α1α2(IV) trimer. In addition to muscular dystrophic features, endothelial cell defects of the muscle capillaries were observed, with intracytoplasmic accumulation of the mutant α1α1α2(IV) molecules, endoplasmic reticulum cisternae dilation, and up-regulation of endoplasmic reticulum stress markers. Induction of the unfolded protein response in Col4a1 mutant muscle tissue resulted in an excess of apoptosis in endothelial cells. HANAC mutant animals also presented with a muscular functional impairment and increased serum creatine kinase levels reflecting altered muscle fiber sarcolemma. This extensive description of the muscular phenotype of the Col4a1 HANAC murine model suggests a potential contribution of primary endothelial cell defects, together with muscle BM alterations, to the development of COL4A1-related myopathy.
authors.affiliation: Mixed Research Unit S1155, INSERM, Paris, France; University Pierre and Marie Curie Paris 06, Sorbonne University, Paris, France; Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom.
authors.forename: Simon
authors.initials: S
authors.lastname: Guiraud
authors.affiliation: Mixed Research Unit S1155, INSERM, Paris, France; University Pierre and Marie Curie Paris 06, Sorbonne University, Paris, France.
authors.forename: Tiffany
authors.initials: T
authors.lastname: Migeon
authors.affiliation: Research Center in Myology, Institut de Myologie, the Inserm UMRS974, CNRS FRE3617, Pitié-Salpêtrière Hospital Group, University Pierre and Marie Curie Paris 06, Paris Descartes University, The Sorbonne University, Paris, France.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Ferry
authors.affiliation: Mixed Research Unit S1155, INSERM, Paris, France.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Mixed Research Unit S1155, INSERM, Paris, France; University Pierre and Marie Curie Paris 06, Sorbonne University, Paris, France.
authors.forename: Souhila
authors.initials: S
authors.lastname: Ouchelouche
authors.affiliation: Mixed Research Unit S1155, INSERM, Paris, France; University Pierre and Marie Curie Paris 06, Sorbonne University, Paris, France.
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Verpont
authors.affiliation: Shigei Medical Research Institute, Okayama, Japan.
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Sado
authors.affiliation: Research Center in Myology, Institut de Myologie, the Inserm UMRS974, CNRS FRE3617, Pitié-Salpêtrière Hospital Group, University Pierre and Marie Curie Paris 06, Paris Descartes University, The Sorbonne University, Paris, France.
authors.forename: Valérie
authors.initials: V
authors.lastname: Allamand
authors.affiliation: Mixed Research Unit S1155, INSERM, Paris, France; University Pierre and Marie Curie Paris 06, Sorbonne University, Paris, France; Department of Nephrology and Dialysis, Assistance Publique-Hôpitaux de Paris, Tenon Hospital, Paris, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Ronco
authors.affiliation: Mixed Research Unit S1155, INSERM, Paris, France; University Pierre and Marie Curie Paris 06, Sorbonne University, Paris, France; Department of Nephrology and Dialysis, Assistance Publique-Hôpitaux de Paris, Tenon Hospital, Paris, France. Electronic address: emmanuelle.plaisier@tnn.aphp.fr.
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Plaisier
mesh_terms: D000818:Animals; D017209:Apoptosis; D001808:Blood Vessels / Q000002:abnormalities* / Q000473:pathology; D001835:Body Weight; D024141:Collagen Type IV / Q000235:genetics*; D003402:Creatine Kinase / Q000097:blood; D016189:Dystrophin / Q000378:metabolism; D059865:Endoplasmic Reticulum Stress; D042783:Endothelial Cells / Q000473:pathology / Q000648:ultrastructure; D005109:Extracellular Matrix / Q000378:metabolism; D019012:Integrin beta1 / Q000378:metabolism; D051379:Mice; D008817:Mice, Mutant Strains; D009120:Muscle Cramp / Q000235:genetics*; D018482:Muscle, Skeletal / Q000098:blood supply* / Q000473:pathology* / Q000648:ultrastructure; D009154:Mutation / Q000235:genetics*; D009929:Organ Size; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D011928:Raynaud Disease / Q000235:genetics*
chemical_list: C000619517:Col4a1 protein, mouse; D024141:Collagen Type IV; D016189:Dystrophin; D019012:Integrin beta1; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D003402:Creatine Kinase