Prostaglandin E2 enhances transforming growth factor-beta 1 and TGF-beta receptors synthesis: An in vivo and in vitro study

The aims of this study were to determine how Prostaglandin E2 (PGE2) locally applied affected the immunodistribution of latent transforming growth factor-beta 1 (TGF-β1), and how the eicosanoid modified TGF-β1 release and TGF-β receptors gene expression in cultured osteoblasts. PGE2 locally delivered on the rat mandible at doses of 0.1 and 0.05 mg/day, but not 0.025 mg/day, over 20 days significantly increased latent TGF-β  1 immunodistribution (P<0.001P<0.001), comparing with a placebo-treated group. Cultured osteoblasts stimulated with 10−5 or 10−7 M PGE2 significantly varied the level of activated TGF-β1 released into supernatants at different experimental periods compared with negative and positive controls. TGF-β   receptor type I gene expression was significantly increased in osteoblasts (P<0.01P<0.01) after 10 days of treatment with 10−5 and 10−7 M PGE2, whereas 10−3 M PGE2 produced the opposite effect. It is concluded that PGE2 may stimulate bone deposition by affecting TGF-β pathway. This effect on the pathway appears to be dose-dependent.