Involvement of Rho-kinase in prostaglandin E(1)-stimulated VEGF synthesis through stress-activated protein kinase/c-Jun N-terminal kinase in osteoblast-like MC3T3-E1 cells.
We have previously shown that prostaglandin E(1) (PGE(1)) stimulates the synthesis of vascular endothelial growth factor (VEGF) through p38 mitogen-activated protein (MAP) kinase and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) but not p44/p42 MAP kinase in osteoblast-like MC3T3-E1 cells. In the present study, we investigated the involvement of Rho-kinase in the PGE(1)-stimulated VEGF synthesis in these cells. PGE(1) induced within 3min the phosphorylation of myosin phosphatase targeting subunit (MYPT-1), a substrate of Rho-kinase. Y27632 and fasudil, specific inhibitors of Rho-kinase, which attenuated the MYPT-1 phosphorylation, significantly suppressed the PGE(1)-stimulated VEGF synthesis. Y27632 and fasudil markedly reduced the PGE(1)-induced phosphorylation of SAPK/JNK without affecting the phosphorylation levels of p38 MAP kinase or p44/p42 MAP kinase. These results strongly suggest that Rho-kinase functions at a point upstream of SAPK/JNK and regulates PGE(1)-stimulated VEGF synthesis in osteoblasts.
Adachi
Seiji
S
Department of Pharmacology, Gifu University Graduate School of Medicine, Gifu 501-1194, Japan.
Tokuda
Haruhiko
H
Matsushima-Nishiwaki
Rie
R
Kato
Kenji
K
Natsume
Hideo
H
Minamitani
Chiho
C
Mizutani
Jun
J
Otsuka
Takanobu
T
Kozawa
Osamu
O
D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine / Q000031:analogs & derivatives / Q000494:pharmacology; D016475:3T3 Cells; D000527:Alprostadil / Q000494:pharmacology*; D000577:Amides / Q000494:pharmacology; D000818:Animals; D002460:Cell Line; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism*; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D009219:Myosin-Light-Chain Kinase / Q000378:metabolism; D043263:Myosin-Light-Chain Phosphatase; D010006:Osteoblasts / Q000166:cytology*; D010766:Phosphorylation / Q000187:drug effects; D011725:Pyridines / Q000494:pharmacology; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis*; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism; D054460:rho-Associated Kinases / Q000378:metabolism*
D000577:Amides; D011725:Pyridines; D042461:Vascular Endothelial Growth Factor A; C108830:Y 27632; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D054460:rho-Associated Kinases; D009219:Myosin-Light-Chain Kinase; D048031:JNK Mitogen-Activated Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D048051:p38 Mitogen-Activated Protein Kinases; D043263:Myosin-Light-Chain Phosphatase; C510645:Ppp1r12a protein, mouse; D000527:Alprostadil; C049347:fasudil