title: Fast-twitch sarcomeric and glycolytic enzyme protein loss in inclusion body myositis.
abstract: Inclusion body myositis (IBM) is an inflammatory disease of skeletal muscle of unknown cause. To further understand the nature of the tissue injury in this disease, we developed methods for large-scale detection and quantitation of proteins in muscle biopsy samples and analyzed proteomic data produced by these methods together with histochemical, immunohistochemical, and microarray data. Twenty muscle biopsy samples from patients with inflammatory myopathies (n = 17) or elderly subjects without neuromuscular disease (n = 3) were profiled by proteomic studies using liquid chromatographic separation of peptides followed by mass spectrometry. Thirteen of the diseased samples additionally underwent microarray studies. Seventy muscle specimens from patients with a range of neuromuscular disorders were examined by ATPase histochemical methods. Smaller numbers of samples underwent immunohistochemical and immunoblot studies. Mass spectrometric studies identified and quantified approximately 300 total distinct proteins in each muscle sample. In IBM and to a lesser extent in polymyositis, proteomic studies confirmed by histochemical, immunohistochemical, and immunoblot studies showed loss of many fast-twitch specific structural proteins and glycolytic enzymes despite relative preservation of transcript levels. Increased abundance of a nuclear membrane protein, immunoglobulins, and two calpain-3 substrates were present. The atrophy present in IBM muscle is accompanied by preferential loss of fast-twitch structural proteins and glycolytic enzymes, particularly glycogen debranching enzyme, with relative preservation of the abundance of their respective transcripts. Although muscle atrophy has long been recognized in IBM, these studies are the first to report specific proteins which are reduced in quantity in IBM muscle.
authors.affiliation: Harvard-Partners Center for Genetics and Genomics, Proteomics Core, Harvard Medical School, Boston, Massachusetts USA.
authors.forename: Kenneth C
authors.initials: KC
authors.lastname: Parker
authors.forename: Sek Won
authors.initials: SW
authors.lastname: Kong
authors.forename: Ronan J
authors.initials: RJ
authors.lastname: Walsh
authors.forename: Mohammad
authors.initials: M
authors.lastname: Salajegheh
authors.forename: Behzad
authors.initials: B
authors.lastname: Moghadaszadeh
authors.forename: Anthony A
authors.initials: AA
authors.lastname: Amato
authors.forename: Remedios
authors.initials: R
authors.lastname: Nazareno
authors.forename: Yin Yin
authors.initials: YY
authors.lastname: Lin
authors.forename: Bryan
authors.initials: B
authors.lastname: Krastins
authors.forename: David A
authors.initials: DA
authors.lastname: Sarracino
authors.forename: Alan H
authors.initials: AH
authors.lastname: Beggs
authors.forename: Jack L
authors.initials: JL
authors.lastname: Pinkus
authors.forename: Steven A
authors.initials: SA
authors.lastname: Greenberg
mesh_terms: D000185:Actinin / Q000172:deficiency / Q000235:genetics; D000328:Adult; D000368:Aged; D001706:Biopsy; D002154:Calpain / Q000032:analysis / Q000378:metabolism; D002853:Chromatography, Liquid; D015536:Down-Regulation / Q000235:genetics; D004798:Enzymes / Q000032:analysis / Q000172:deficiency* / Q000235:genetics; D006010:Glycogen Storage Disease Type III / Q000175:diagnosis; D006019:Glycolysis / Q000235:genetics; D006801:Humans; D013058:Mass Spectrometry; D008875:Middle Aged; D018656:Muscle Fibers, Fast-Twitch / Q000378:metabolism* / Q000473:pathology; D009124:Muscle Proteins / Q000032:analysis / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D018995:Myosin Heavy Chains / Q000172:deficiency / Q000235:genetics; D018979:Myositis, Inclusion Body / Q000235:genetics / Q000378:metabolism* / Q000503:physiopathology; D009685:Nuclear Envelope / Q000378:metabolism; D040901:Proteomics / Q000379:methods; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D012518:Sarcomeres / Q000378:metabolism* / Q000473:pathology
chemical_list: C118456:ACTN3 protein, human; D004798:Enzymes; D009124:Muscle Proteins; D012333:RNA, Messenger; D000185:Actinin; C105884:CAPN3 protein, human; D002154:Calpain; D018995:Myosin Heavy Chains