title: Development of podocyte injuries in Osborne-Mendel rats is accompanied by reduced expression of podocyte proteins.
abstract: Osborne-Mendel (OM) rats spontaneously develop glomerulopathy with progressive podocyte injury. Changes in protein expression levels in the foot processes of podocytes have been suggested to play an important role in the development of renal disease. The aim of this study was to investigate the temporal relationship between the expression of five podocyte proteins (nephrin, podocin, synaptopodin, α-actinin-4 and α3-integrin) and the development of podocyte injuries, proteinuria and glomerulosclerosis in OM rats. Male OM rats 5-20 weeks of age and age-matched Fischer 344 rats were used. Semiquantitative analysis of expression of the five podocyte proteins was performed by immunofluorescence labelling. Nephrin mRNA expression was determined by quantitative real-time reverse transcriptase polymerase chain reaction and nephrin protein expression was determined by mass spectrometry. Progressive reduction in expression of the podocyte proteins correlated with the progression of podocyte injuries, the development of proteinuria and the subsequent development of glomerulosclerosis. Nephrin mRNA expression and nephrin concentration also showed temporal decreases in OM rats. Altered expression of podocyte proteins preceded the development of proteinuria and glomerulosclerosis, suggesting that this event contributes to podocyte dysfunction and progression to glomerulosclerosis.
authors.affiliation: Research Institute of Biosciences, School of Veterinary Medicine, Azabu University, Kanagawa, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yasuno
authors.forename: S
authors.initials: S
authors.lastname: Araki
authors.forename: H
authors.initials: H
authors.lastname: Sakashita
authors.forename: R
authors.initials: R
authors.lastname: Kobayashi
authors.forename: T
authors.initials: T
authors.lastname: Baba
authors.forename: H
authors.initials: H
authors.lastname: Kawakami
authors.forename: J
authors.initials: J
authors.lastname: Kamiie
authors.forename: K
authors.initials: K
authors.lastname: Ogihara
authors.forename: K
authors.initials: K
authors.lastname: Shirota
mesh_terms: D000185:Actinin / Q000032:analysis / Q000096:biosynthesis*; D000818:Animals; D015153:Blotting, Western; D005455:Fluorescent Antibody Technique; D005923:Glomerulosclerosis, Focal Segmental / Q000378:metabolism* / Q000473:pathology; D047908:Intracellular Signaling Peptides and Proteins / Q000032:analysis / Q000096:biosynthesis*; D008297:Male; D008565:Membrane Proteins / Q000032:analysis / Q000096:biosynthesis*; D042282:Microdissection; D008840:Microfilament Proteins / Q000032:analysis / Q000096:biosynthesis*; D050199:Podocytes / Q000378:metabolism* / Q000473:pathology; D011507:Proteinuria / Q000378:metabolism / Q000473:pathology; D051381:Rats; D060888:Real-Time Polymerase Chain Reaction
chemical_list: C491751:Actn4 protein, rat; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D008840:Microfilament Proteins; C407223:NPHS2 protein; C503969:Synpo protein, rat; C113267:nephrin; D000185:Actinin
keywords: Osborne–Mendel rat; glomerulopathy; podocyte; proteinuria