TY - JOUR
T1 - Basic fibroblast growth factor induces interleukin-6 synthesis in osteoblasts
T2 - Autoregulation by protein kinase C
AU - Kozawa, Osamu
AU - Suzuki, Atsushi
AU - Uematsu, Toshihiko
PY - 1997/9
Y1 - 1997/9
N2 - We previously reported that basic fibroblast growth factor (bFGF) stimulates both phospholipases C and D via independent pathways in osteoblastlike MC3T3-E1 cells. In this study, we investigated the effect of bFGF on interleukin-6 (IL-6) synthesis in these cells. bFGF stimulated the IL-6 synthesis dose-dependently in the range between 1 and 30 ng/ml. The depletion of extracellular Ca2+ by EGTA suppressed the bFGF-induced IL-6 synthesis. TMB-8, an inhibitor of intracellular Ca2+ mobilization, also inhibited the IL-6 synthesis by bFGF. bFGF stimulated the Ca2+ influx from extracellular space. Genistein, a tyrosine kinase inhibitor, suppressed the bFGF-induced Ca2+ influx. Staurosporine, an inhibitor for protein kinases, enhanced the bFGF-induced IL-6 synthesis. Calphostin C, a highly potent and specific inhibitor for protein kinase C (PKC), also enhanced the IL-6 synthesis by bFGF. The bFGF-induced IL-6 synthesis was amplified in PKC down-regulated cells. U-73122, a phospholipase C inhibitor, enhanced the bFGF induced IL-6 synthesis. Propranolol, a phosphatidic acid phosphohydrolase inhibitor, also enhanced the IL-6 synthesis by bFGF. These results strongly suggest that bFGF stimulates IL-6 synthesis, which depends on intracellular Ca2+ mobilization in osteoblastlike cells, and that the IL-6 synthesis by bFGF is autoregulated due to PKC activation.
AB - We previously reported that basic fibroblast growth factor (bFGF) stimulates both phospholipases C and D via independent pathways in osteoblastlike MC3T3-E1 cells. In this study, we investigated the effect of bFGF on interleukin-6 (IL-6) synthesis in these cells. bFGF stimulated the IL-6 synthesis dose-dependently in the range between 1 and 30 ng/ml. The depletion of extracellular Ca2+ by EGTA suppressed the bFGF-induced IL-6 synthesis. TMB-8, an inhibitor of intracellular Ca2+ mobilization, also inhibited the IL-6 synthesis by bFGF. bFGF stimulated the Ca2+ influx from extracellular space. Genistein, a tyrosine kinase inhibitor, suppressed the bFGF-induced Ca2+ influx. Staurosporine, an inhibitor for protein kinases, enhanced the bFGF-induced IL-6 synthesis. Calphostin C, a highly potent and specific inhibitor for protein kinase C (PKC), also enhanced the IL-6 synthesis by bFGF. The bFGF-induced IL-6 synthesis was amplified in PKC down-regulated cells. U-73122, a phospholipase C inhibitor, enhanced the bFGF induced IL-6 synthesis. Propranolol, a phosphatidic acid phosphohydrolase inhibitor, also enhanced the IL-6 synthesis by bFGF. These results strongly suggest that bFGF stimulates IL-6 synthesis, which depends on intracellular Ca2+ mobilization in osteoblastlike cells, and that the IL-6 synthesis by bFGF is autoregulated due to PKC activation.
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U2 - 10.1016/S0898-6568(97)00043-0
DO - 10.1016/S0898-6568(97)00043-0
M3 - Article
C2 - 9376229
AN - SCOPUS:0030826765
SN - 0898-6568
VL - 9
SP - 463
EP - 468
JO - Cellular Signalling
JF - Cellular Signalling
IS - 6
ER -