{"title":"Myopathic changes caused by protein aggregates in adult-onset spinal muscular atrophy.","authors":"Satoshi Yamashita, Akihito Nagatoshi, Yosuke Takeuchi, Ichizo Nishino, Mitsuharu Ueda","doi":"10.1111/neup.12901","DOIUrl":null,"url":null,"abstract":"<p><p>Spinal muscular atrophy (SMA), an autosomal-recessive lower motor neuron disease, causes progressive proximal muscle waste and weakness. It remains unclear whether myopathic changes are involved in pathogenesis. We encountered a patient with adult-onset SMA caused by a homozygous deletion in exon 7 of the survival motor neuron 1 (SMN1) gene who had had four copies of SMN2 exon 7. Muscle biopsy showed neurogenic features of groups of atrophic fibers, fiber-type grouping, and pyknotic nuclear clumps associated with fibers with rimmed vacuoles. Immunohistochemistry revealed sarcoplasmic aggregates of phosphorylated TDP-43 and p62 but not SMN. This study demonstrated myopathic changes with the accumulation of phosphorylated p62 and TDP-43 in the muscles of a patient with SMA, suggesting that abnormal protein aggregation may be involved in myopathic pathology.</p>","PeriodicalId":19204,"journal":{"name":"Neuropathology","volume":null,"pages":null},"PeriodicalIF":1.3000,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Neuropathology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1111/neup.12901","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2023/3/2 0:00:00","PubModel":"Epub","JCR":"Q4","JCRName":"CLINICAL NEUROLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Spinal muscular atrophy (SMA), an autosomal-recessive lower motor neuron disease, causes progressive proximal muscle waste and weakness. It remains unclear whether myopathic changes are involved in pathogenesis. We encountered a patient with adult-onset SMA caused by a homozygous deletion in exon 7 of the survival motor neuron 1 (SMN1) gene who had had four copies of SMN2 exon 7. Muscle biopsy showed neurogenic features of groups of atrophic fibers, fiber-type grouping, and pyknotic nuclear clumps associated with fibers with rimmed vacuoles. Immunohistochemistry revealed sarcoplasmic aggregates of phosphorylated TDP-43 and p62 but not SMN. This study demonstrated myopathic changes with the accumulation of phosphorylated p62 and TDP-43 in the muscles of a patient with SMA, suggesting that abnormal protein aggregation may be involved in myopathic pathology.
期刊介绍:
Neuropathology is an international journal sponsored by the Japanese Society of Neuropathology and publishes peer-reviewed original papers dealing with all aspects of human and experimental neuropathology and related fields of research. The Journal aims to promote the international exchange of results and encourages authors from all countries to submit papers in the following categories: Original Articles, Case Reports, Short Communications, Occasional Reviews, Editorials and Letters to the Editor. All articles are peer-reviewed by at least two researchers expert in the field of the submitted paper.