title: Skeletal muscle tissue from the Goto-Kakizaki rat model of type-2 diabetes exhibits increased levels of the small heat shock protein Hsp27.
abstract: In order to increase our understanding of diabetes-related muscle weakness, we carried out a mass spectrometry-based proteomic analysis of skeletal muscle preparations from the Goto-Kakizaki rat model of type-2 diabetes. Fluorescence difference in-gel electrophoresis was performed to determine potential differences in the global protein expression profile of muscle extracts. Besides changes in contractile proteins and metabolic enzymes, the abundance of the small stress proteins αB-crystallin and Hsp27 was significantly increased. The up-regulation of the low-molecular-mass heat shock protein Hsp27 was confirmed by an alternative fluorescent staining method of two-dimensional gels and immunoblotting. The observed protein alterations in the cellular stress response, distinct metabolic pathways, regulatory mechanisms and the contractile apparatus might be directly or indirectly associated with peripheral resistance to insulin signalling, making these newly identified muscle proteins potential biomarkers of type-2 diabetes. Increased levels of molecular chaperones suggest considerably enhanced cellular stress levels in diabetic muscle fibres.
authors.affiliation: Department of Biology, National University of Ireland, Maynooth, County Kildare, Ireland.
authors.forename: Edel
authors.initials: E
authors.lastname: Mullen
authors.forename: Elaine
authors.initials: E
authors.lastname: O'Reilly
authors.forename: Kay
authors.initials: K
authors.lastname: Ohlendieck
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism* / Q000473:pathology; D015180:Electrophoresis, Gel, Two-Dimensional; D055551:HSP27 Heat-Shock Proteins / Q000737:chemistry / Q000378:metabolism*; D050888:Heat-Shock Proteins, Small / Q000737:chemistry / Q000378:metabolism*; D015151:Immunoblotting; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000473:pathology*; D009942:Organometallic Compounds / Q000378:metabolism; D010449:Peptide Mapping; D010618:Phenanthrolines / Q000378:metabolism; D040901:Proteomics; D051381:Rats; D014020:Tissue Extracts
chemical_list: D055551:HSP27 Heat-Shock Proteins; D050888:Heat-Shock Proteins, Small; C486114:Hspb1 protein, rat; D009942:Organometallic Compounds; D010618:Phenanthrolines; D014020:Tissue Extracts; C518776:ruthenium II tris (bathophenanthroline disulfonate)