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Recombinant human interleukin-1{beta} (rhIL-1{beta}) regulates several activities of the osteoblast cells derived from mouse calvarial bone explants in vitro. rhIL-1{beta} stimulated cellular proliferation and the synthesis of prostaglandin E_2(PGE_2) and plasminogen activator activity in the cultured cells in a dose-dependent manner. However, the induction of osteocalcin synthesis and alkaine phosphatase activity in response to vitamine D, two characteristics of the osteoblast phenotype, were antagonized by rhIL-1{beta} over a similar dose range. This study supports the role of IL-1{beta} in the pathological modulation of bone cell metabolism, with regard to implication in the pathogenesis of osteoporosis by IL-1{beta}. When the mouse calvarial bone cells were used, the bone resorption induced by IL-1{beta} was strongly inhibited by calcitonin treatment, indicating osteoclast-mediated bone resorption. On the other hand, the medicinal extracts of Taeyoungjon-Jahage (T.Y.J-J.H.G extracts) was tested for whether they could inhibit IL-1{beta}-induced PGE_2 production. Cell viability was not significantly affected by treatment with the indicated concentration of the extracts. The T.Y.J.-J.H.G. extracts were shown to have the inhibitory effects against the synthesis of PGE_2. We also examined the effect of the pretreatment with a various concentrations of the T.Y.J.-J.H.G. extracts then treated the PGE_2-induction agents. Pretreatment of the T.Y.J.-J.H.G. extracts for 1 h, which by itself had little effect on cell survival, did not enhance the synthesis of PGE_2. Furthermore, the T.Y.J-J.H.G. extracts were shown to have the protective effects against plasminogen dependent fibrinolysis induced by the bone resorption agents of IL-1{beta}. Pretreatment of the T.Y.J.-J.H.G. extracts for 1 h did not enhance the plasminogen dependent fibrinolysis. Finally, calcitonin showed the inhibitory activity the IL-1{beta}-stimulated bone resorption in the mouse calvarial bone cells having both of the osteoblast and osteoclast cells. Seemingly, pretreatment of the T.Y.J.-J.H.G. extracts for 1 h reduced the bone resorption. These results clearly indicated that calcitonin and T.Y.J.-J.H.G. extracts play key roles in inhibition of the osteoclast-mediated bone resorption.
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