Endothelin-1 stimulates heat shock protein 27 induction in osteoblasts: involvement of p38 MAP kinase.
We previously reported that endothelin-1 (ET-1) activates p42/p44 mitogen-activated protein (MAP) kinase in osteoblast-like MC3T3-E1 cells and consequently induces synthesis of interleukin-6. In the present study, we investigated the effect of ET-1 on the induction of heat shock protein 27 (HSP 27) in MC3T3-E1 cells. ET-1 time and dose dependently stimulated HSP 27 accumulation. ET-1 induced an increase in the levels of mRNA for HSP 27. Both staurosporine and calphostin C, inhibitors of protein kinase C (PKC), suppressed the ET-1-induced HSP 27 accumulation. 12-O-tetradecanoylphorbol 13-acetate (TPA), a PKC activator, induced the HSP 27 accumulation and the expression of mRNA for HSP 27. The ET-1-stimulated HSP 27 accumulation was reduced in PKC-downregulated MC3T3-E1 cells. The HSP 27 accumulation by ET-1 was not suppressed by PD-98059, an inhibitor of the upstream kinase that activates p42/p44 MAP kinase. ET-1 or TPA induced the phosphorylation of p38 MAP kinase. SB-203580, an inhibitor of p38 MAP kinase, reduced the ET-1-stimulated HSP 27 accumulation. Calphostin C and U-73122, a phospholipase C inhibitor, suppressed the ET-1-induced phosphorylation of p38 MAP kinase. U-73122 and propranolol, a phosphatidic acid phosphohydrolase inhibitor, reduced the ET-1-stimulated HSP 27 accumulation. SB-203580 suppressed the ET-1-stimulated increase in the mRNA levels for HSP 27. These results strongly suggest that ET-1 stimulates HSP 27 induction in osteoblasts and that p38 MAP kinase activation is involved in the HSP 27 induction.
Kawamura
H
H
Department of Pharmacology, Gifu University School of Medicine, Gifu 500-8705, Japan.
Otsuka
T
T
Matsuno
H
H
Niwa
M
M
Matsui
N
N
Kato
K
K
Uematsu
T
T
Kozawa
O
O
D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology; D015152:Blotting, Northern; D002273:Carcinogens / Q000494:pharmacology; D002478:Cells, Cultured; D019332:Endothelin-1 / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004963:Estrenes / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D019833:Genistein / Q000494:pharmacology; D006360:Heat-Shock Proteins / Q000235:genetics*; D007093:Imidazoles / Q000494:pharmacology; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009281:Naphthalenes / Q000494:pharmacology; D009842:Oligopeptides / Q000494:pharmacology; D010006:Osteoblasts / Q000166:cytology* / Q000201:enzymology*; D010456:Peptides, Cyclic / Q000494:pharmacology; D010703:Phorbol Esters / Q000494:pharmacology; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D010766:Phosphorylation; D010880:Piperidines / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism; D011725:Pyridines / Q000494:pharmacology; D011760:Pyrrolidinones / Q000494:pharmacology; D012333:RNA, Messenger / Q000032:analysis; D012886:Skull / Q000166:cytology; D019311:Staurosporine / Q000494:pharmacology; D048051:p38 Mitogen-Activated Protein Kinases
D000959:Antihypertensive Agents; D002273:Carcinogens; D019332:Endothelin-1; D004791:Enzyme Inhibitors; D004963:Estrenes; D005419:Flavonoids; D006360:Heat-Shock Proteins; D007093:Imidazoles; D009281:Naphthalenes; D009842:Oligopeptides; D010456:Peptides, Cyclic; D010703:Phorbol Esters; D010726:Phosphodiesterase Inhibitors; D010880:Piperidines; D011725:Pyridines; D011760:Pyrrolidinones; D012333:RNA, Messenger; C060229:1-(6-((3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione; C086539:BQ 788; D011433:Propranolol; D019833:Genistein; D011493:Protein Kinase C; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D019311:Staurosporine; C058819:calphostin C; C093642:SB 203580; C072247:cyclo(Trp-Asp-Pro-Val-Leu); C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one