Y-27632 prevents tubulointerstitial fibrosis in mouse kidneys with unilateral ureteral obstruction.
BACKGROUND
The small GTPase Rho is involved in cell-to-substratum adhesion and cell contraction. These actions of Rho mediated by downstream Rho effectors such as Rho-associated coiled-coil forming protein kinase (ROCK) may be partly responsible for the progression of renal interstitial fibrosis.


METHODS
The anti-fibrosis effects of Y-27632, a specific ROCK inhibitor, were studied both in vivo (unilateral ureteral obstruction; UUO) and in vitro. To investigate the therapeutic efficacy of Y-27632 in UUO kidneys, smooth muscle alpha actin (SMalphaA) expression, macrophage infiltration and fibrosis in the obstructed kidneys were studied. SMalphaA, transforming growth factor beta (TGF-beta), alpha1 (I) collagen, osteopontin, macrophage chemoattractant peptide-1 (MCP-1), and intercellular adhesion molecule-1 (ICAM-1) gene expression were examined by Northern blotting. To elucidate the mechanism linking the Rho-ROCK pathway with renal fibrosis, the effects of Y-27632 on in vitro cell proliferation and cell migration were studied.


RESULTS
In vivo analysis showed that Y-27632 suppressed SMalphaA expression, macrophage infiltration and interstitial fibrosis, and that Y-27632 suppressed SMalphaA, TGF-beta and alpha1 (I) collagen mRNA expression. In vitro analysis showed that Y-27632 did not suppress proliferation of renal fibroblasts but suppressed migration of macrophages.


CONCLUSIONS
The Rho-ROCK system may play an important role in the development of tissue fibrosis, and the Rho-ROCK signaling pathway may be a new therapeutic target for preventing interstitial fibrosis in progressive renal disease.
Nagatoya
Katsuyuki
K
Department of Internal Medicine and Therapeutics, Osaka University Graduate School of Medicine, and School ofHealth and Sport Sciences, Osaka University, Osaka, Japan.
Moriyama
Toshiki
T
Kawada
Noritaka
N
Takeji
Masanobu
M
Oseto
Susumu
S
Murozono
Takahiro
T
Ando
Akio
A
Imai
Enyu
E
Hori
Masatsugu
M
D000199:Actins / Q000235:genetics; D000284:Administration, Oral; D000577:Amides / Q000494:pharmacology*; D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects / Q000276:immunology; D002478:Cells, Cultured; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005347:Fibroblasts / Q000166:cytology / Q000502:physiology; D005355:Fibrosis; D015870:Gene Expression / Q000187:drug effects; D047908:Intracellular Signaling Peptides and Proteins; D007668:Kidney / Q000473:pathology*; D008264:Macrophages / Q000166:cytology / Q000187:drug effects; D051379:Mice; D009395:Nephritis, Interstitial / Q000188:drug therapy* / Q000473:pathology / Q000517:prevention & control; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000235:genetics; D011725:Pyridines / Q000494:pharmacology*; D012333:RNA, Messenger / Q000032:analysis; D015398:Signal Transduction / Q000187:drug effects; D014517:Ureteral Obstruction / Q000150:complications / Q000473:pathology*; D018631:ras Proteins; D020741:rho GTP-Binding Proteins / Q000235:genetics; D054460:rho-Associated Kinases; D020742:rhoA GTP-Binding Protein / Q000235:genetics; D020743:rhoB GTP-Binding Protein / Q000235:genetics; D000075024:rhoC GTP-Binding Protein
D000199:Actins; D000577:Amides; D004791:Enzyme Inhibitors; D047908:Intracellular Signaling Peptides and Proteins; D011725:Pyridines; D012333:RNA, Messenger; C108830:Y 27632; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases; C512911:Rhoc protein, mouse; D018631:ras Proteins; D020741:rho GTP-Binding Proteins; D020742:rhoA GTP-Binding Protein; D020743:rhoB GTP-Binding Protein; D000075024:rhoC GTP-Binding Protein