title: Therapeutic effect of all-trans retinoic acid on rats with anti-GBM antibody glomerulonephritis.
abstract: BACKGROUND
  All-trans retinoic acid (ATRA) has antiproliferative and anti-inflammatory effects and is currently used in the treatment of leukemia and dermatologic diseases. We tested the therapeutic potential of ATRA on anti-glomerular basement membrane (GBM) glomerulonephritis rats.
  
  
  METHODS
  Glomerulonephritis was induced in male Wistar-Kyoto rats on day 0 by an intravenous injection of antirat GBM antibody. On day 14 after the induction of anti-GBM glomerulonephritis, some rats were sacrificed (N = 5). Another 10 rats were divided into two groups: the vehicle group (N = 5) and the ATRA treated group (N = 5). ATRA was orally administrated from day 14 to day 27 after disease induction. Blood pressure, body weight, urinary protein excretion, and blood chemistry was determined on days 1, 14, 21, and 27. Kidney samples were obtained on day 28. The kidneys were examined with periodic acid-Schiff staining (PAS) and immunohistochemistry using antibodies against the proliferative cell nuclear antigen (PCNA), rat monocyte and macrophage (ED-1), and alpha-smooth muscle actin (alpha-SMA). Glomerular RNA was extracted from isolated glomeruli, and reverse transcription (RT) followed by polymerase chain reaction (PCR) was performed.
  
  
  RESULTS
  ATRA administration produced a 55% reduction of proteinuria in glomerulonephritis rats. Light microscopic analysis revealed severe necrosis/crescent formation (>50% of the glomerulus) affecting 34% of glomeruli in vehicle rats, whereas ATRA treatment reduced the glomeruli showing severe change to 14%. ATRA also significantly reduced PCNA-positive cells, ED-1-positive cells and alpha-SMA-positive area in the glomeruli. RT-PCR analyses revealed that a wide variety of genes including inflammation related [tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and CCAAT enhancer-binding protein delta (C/EBPdelta)], cell proliferation-related [platelet-derived growth factor (PDGF)] and fibrosis-related [transforming growth factor-beta1 (TGF-beta1), type I collagen, and alpha-SMA) genes were suppressed in the glomeruli of ATRA-treated rats.
  
  
  CONCLUSIONS
  ATRA administration significantly reduced severe necrosis/crescent formation and urinary protein excretion in glomerulonephritis rats. Suppression of a wide variety of gene expression may partly explain the mechanism of ATRA's antiproliferative and anti-inflammatory effects. These data suggest a novel therapeutic application of ATRA toward glomerulonephritis.
authors.affiliation: Department of Internal Medicine and Therapeutics, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Oseto
authors.forename: Toshiki
authors.initials: T
authors.lastname: Moriyama
authors.forename: Noritaka
authors.initials: N
authors.lastname: Kawada
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Nagatoya
authors.forename: Masanobu
authors.initials: M
authors.lastname: Takeji
authors.forename: Akio
authors.initials: A
authors.lastname: Ando
authors.forename: Tadashi
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Enyu
authors.initials: E
authors.lastname: Imai
authors.forename: Masatsugu
authors.initials: M
authors.lastname: Hori
mesh_terms: D000818:Animals; D019867:Anti-Glomerular Basement Membrane Disease / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology / Q000652:urine; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D015870:Gene Expression / Q000187:drug effects; D007668:Kidney / Q000187:drug effects / Q000473:pathology*; D007678:Kidney Glomerulus / Q000503:physiopathology; D008297:Male; D009336:Necrosis; D011507:Proteinuria / Q000209:etiology / Q000652:urine; D051381:Rats; D011921:Rats, Inbred WKY; D014212:Tretinoin / Q000494:pharmacology*
chemical_list: D000893:Anti-Inflammatory Agents; D014212:Tretinoin