title: [Pathogenesis of inclusion body myositis: autoimmune or degenerative disease?].
abstract: While the pathogenesis of inclusion body myositis (IBM) remains undetermined, there are two major hypotheses: the autoimmune hypothesis and the degeneration hypothesis. Herein, we review these hypotheses as well as potential therapeutic approaches. Evidence in favor of a primary autoimmune etiology includes the frequent complication of other autoimmune diseases in patients with IBM and the presence of autoantibodies against cytosolic 5'-nucleotidase 1A. Interleukin (IL)-1β reportedly leads to accumulation of amyloid β via nitric oxide stress in vitro. The degeneration hypothesis addresses the following aspects of IBM: accumulation of amyloid β and other abnormal proteins that are observed in neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease; relation to aging; and poor response to immunotherapy. Overexpression of IL-1β in skeletal muscles of patients with IBM and its secretion from skeletal muscle cells suggests an important role for IL-1β in the pathogenesis of IBM. Thus, IL-1β is a potential treatment target.
authors.affiliation: Department of Clinical Development, Translational Medical Center, National Center of Neurology and Psychiatry (NCNP).
authors.forename: Akinori
authors.initials: A
authors.lastname: Uruha
authors.forename: Ichizo
authors.initials: I
authors.lastname: Nishino
mesh_terms: D000375:Aging; D016229:Amyloid beta-Peptides / Q000378:metabolism; D001323:Autoantibodies / Q000276:immunology / Q000378:metabolism; D001327:Autoimmune Diseases / Q000276:immunology* / Q000378:metabolism; D016207:Cytokines / Q000276:immunology; D006801:Humans; D018979:Myositis, Inclusion Body / Q000175:diagnosis / Q000276:immunology / Q000473:pathology* / Q000628:therapy
chemical_list: D016229:Amyloid beta-Peptides; D001323:Autoantibodies; D016207:Cytokines