In previous studies we have shown that IL- 1β induced both PGE2 release and total cellular cPLA2 activity and cPLA2 protein synthesis in human amnion-derived WISH cells. In this study, the effect of IL-1β on cPLA2 and PGHS-2 mRNA expression was investigated. Using RT-PCR, we found that IL-1β (0.1 ng/ml) coordinately induced both cPLA2 and PGHS-2 mRNA expression within 2 hours. The synthetic glucocorticoid dexamethasone (10-10-10-6M) inhibited IL-1β-induced cPLA2 and PGHS-2 mRNA expression activity and protein synthesis and PGE2 release in a concentration dependent manner. In the absence of IL-1β, dexamethasone alone (10-6M) inhibited basal CPLA2 activity, mRNA expression and protein synthesis. In addition, cycloheximide (5 μg/ml) apparently superinduced, but actinomycin D (2 μg/ml) inhibited IL-1β-induced cPLA2 and PGHS-2 mRNA expression suggesting that both are immediate early genes and a transcriptional mechanism is involved in the induction of both CPLA2 and PGHS-2 mRNA by IL-1beta;.
ASJC Scopus subject areas
- Cell Biology