Dexamethasone differentiates NG108-15 cells through cyclooxygenase 1 induction.
Cyclooxygenase (COX) is a key enzyme in the conversion of arachidonic acid into prostanoids which participate in various cellular functions including apoptosis, mitogenesis, inflammation, immune modulation and differentiation. Moreover, the synthetic glucocorticoid, dexamethasone has immune modulating and anti-inflammatory effects in vivo. Recently, dexamethasone was found to enhance retinoic acid-induced neuronal differentiation. In this study, we investigated the mechanisms of dexamethasone-mediated neuronal differentiation. Immunoblotting and morphological analysis demonstrated that dexamethasone induced neuronal differentiation through COX 1 induction. This phenomenon was inhibited by indomethacin, a COX inhibitor. In addition, the addition of exogenous prostaglandin E2 (PGE2), a substance produced by the COX-mediated pathway, triggered neurite outgrowth of cells treated with COX inhibitor. Taken together, COX 1 appears to play an important role in dexamethasone-mediated neuronal differentiation.
Kim
Hyeon Soo
HS
Department of Life Science, Division of Molecular and Life Science, Pohang University of Science and Technology, San 31 Hyoja-dong, Nam-gu, Pohang, Kyungbuk 790-784, Korea.
Song
Minseok
M
Kim
Euikyung
E
Ryu
Sung Ho
SH
Suh
Pann-Ghill
PG
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects*; D051545:Cyclooxygenase 1; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D003907:Dexamethasone / Q000494:pharmacology*; D015232:Dinoprostone / Q000378:metabolism; D004790:Enzyme Induction; D006822:Hybrid Cells; D007213:Indomethacin / Q000494:pharmacology; D007527:Isoenzymes / Q000096:biosynthesis*; D008565:Membrane Proteins; D051379:Mice; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis*; D051381:Rats; D014407:Tumor Cells, Cultured
D000893:Anti-Inflammatory Agents; D016861:Cyclooxygenase Inhibitors; D007527:Isoenzymes; D008565:Membrane Proteins; D003907:Dexamethasone; D051545:Cyclooxygenase 1; D011451:Prostaglandin-Endoperoxide Synthases; C496512:Ptgs1 protein, mouse; C496513:Ptgs1 protein, rat; D015232:Dinoprostone; D007213:Indomethacin