Exp Mol Med.  2003 Jun;35(3):203-210.

Dexamethasone differentiates NG108-15 cells through cyclooxygenase1 induction

• Kim HS
• Song M
• Kim E
• Ryu SH
• Suh PG

Abstract

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.

Keyword

cell differentiation; dexamethasone; neurites; prostaglandin-endoperoxide synthase; prostaglandins indomethacin

MeSH Terms

Animals
Anti-Inflammatory Agents/pharmacology
Cell Differentiation/*drug effects
Cyclooxygenase Inhibitors/pharmacology
Dexamethasone/*pharmacology
Dinoprostone/metabolism
Enzyme Induction
Hybrid Cells
Indomethacin/pharmacology
Isoenzymes/*biosynthesis
Mice
Prostaglandin-Endoperoxide Synthase/*biosynthesis
Rats
Tumor Cells, Cultured