Interleukin-1β stimulates ovarian phospholipase A2 (PLA2) expression and activity : Up-regulation of both secretory and cytosolic PLA2

• Published in: Endocrinology (Philadelphia) 1997, Vol.138 (1), p.314-321
• Main Authors: KOL, S, BEN-SHLOMO, I, ANDO, M, PAYNE, D. W, ADASHI, E. Y
• Format: Article
• Language: English
• Subjects: Arachidonic acid; Biological activity; Biological and medical sciences; Biosynthesis; Cell physiology; Fundamental and applied biological sciences. Psychology; Gene expression; IL-1β; Interleukin 1; Interleukin 1 receptor antagonist; Interleukins; Lecithin; Molecular and cellular biology; Phosphatidylcholine; Phosphatidylethanolamine; Phospholipase; Phospholipase A2; Phospholipids; Receptors; Responses to growth factors, tumor promotors, other factors
• ISSN: 0013-7227; 1945-7170
• DOI: 10.1210/endo.138.1.4898

Interleukin (IL)-1β has been shown to stimulate ovarian prostaglandin biosynthesis. We hypothesized that this effect entails the induction of phospholipase A2 (PLA2). Treatment of cultured whole ovarian dispersates of immature rat origin with IL-1β produced significant increases in [3H]arachidonic acid (AA) release and [3H]prostanoid accumulation as well as increases in cellular PLA2 activity and in secretory PLA2 and cytosolic PLA2 transcripts. Cotreatment with IL-1 receptor antagonist reversed IL-mediated (and basal) release of [3H]labeled AA and prostaglandin products, as well as cellular PLA2 activity. Treatment with IL-1β also promoted a significant decrease in the cellular content of[ 3H]phospholipids (apparently phosphatidylethanolamine but not phosphatidylcholine). These observations establish the ovary as a site of IL-1-dependent sPLA2 and cPLA2 gene expression, document the presence of a possible phosphatidylethanolamine-dependent PLA2 activity in cultured whole ovarian dispersates, reveal the up-regulatory, receptor-mediated action of IL-1β in this regard and suggest the existence of endogenous PLA2-stimulating/IL-1-like bioactivity.