title: Nephrin and podocin expression around the onset of puromycin aminonucleoside nephrosis.
abstract: Decreased expression levels of the glomerular slit membrane proteins, nephrin and podocin, have been reported after the onset of puromycin aminonucleoside (PA) nephrosis. We examined nephrin and podocin expressions prior to the onset of proteinuria of PA nephrosis to elucidate the proteinuria induction mechanism of PA. PA nephrosis was induced by a subcutaneous single injection of 120 mg kg(-1) PA. The mRNA levels of nephrin and podocin in whole kidney total RNA were quantified by the TaqMan real time PCR quantification system. The localization and levels of nephrin and podocin molecules were analyzed by immunofluorescence and Western blotting, respectively. Albuminuria and proteinuria were significant on days 3 and 4 in PA nephrosis rats. The protein levels of nephrin and podocin decreased significantly at day 3. The protein localization of nephrin and podocin changed at day 2 and day 1, respectively. The mRNA level of nephrin increased at day 2 and subsequently decreased at day 4. The podocin mRNA level did not change significantly. In conclusions, the protein level of nephrin and podocin decreased at the onset of albuminuria in the PA nephrosis. However, the first change induced by PA was the change of podocin localization from a linear pattern to a dot-like one prior to the onset of albuminuria.
authors.affiliation: Department of Pharmacology and Toxicology, Kyorin University School of Medicine, Tokyo, Japan. hosoyamd@kyorin-u.ac.jp
authors.forename: Makoto
authors.initials: M
authors.lastname: Hosoyamada
authors.forename: Kunimasa
authors.initials: K
authors.lastname: Yan
authors.forename: Yukino
authors.initials: Y
authors.lastname: Nishibori
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Takiue
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kudo
authors.forename: Hayato
authors.initials: H
authors.lastname: Kawakami
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Shibasaki
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Endou
mesh_terms: D000818:Animals; D047908:Intracellular Signaling Peptides and Proteins; D007678:Kidney Glomerulus / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D009401:Nephrosis / Q000139:chemically induced / Q000378:metabolism*; D011692:Puromycin Aminonucleoside / Q000633:toxicity*; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; C407223:NPHS2 protein; D012333:RNA, Messenger; C113267:nephrin; D011692:Puromycin Aminonucleoside