Regulation of prostaglandin biosynthesis by interleukin-1 in cultured bovine endometrial cells

Abstract

Interleukin-1 (IL1) has been shown to be a potent stimulator of prostaglandin (PG) production in bovine endometrium. The aim of the present study was to determine the cell types in the endometrium (epithelial or stromal cells) responsible for the secretion of PGE2 and PGF2a in response to IL1A, and the intracellular mechanisms of IL1A action. Cultured bovine epithelial and stromal cells were exposed to IL1A or IL1B (0 . 006-3 . 0 nM) for 24 h. IL1A and IL1B dose-dependently stimulated PGE2 and PGF2a production in the stromal cells, but not in the epithelial cells. The stimulatory effect of IL1A (0 . 06-3 . 0 nM) on PG production was greater than that of IL1B.The stimulatory actions of IL1A on PG production was augmented by supplementing arachidonic acid (AA). When the stromal cells were incubated with IL1A and inhibitors of phospholipase (PL) C or PLA2 (1 mM; anthranilic acid), only PLA2 inhibitor completely stopped the stimulatory action of IL1A on PG production. Moreover, a specific cyclooxygenase-2 (COX2) inhibitor blocked the stimulatory effect of IL1A on PG production. IL1A (0 . 06 nM) promoted COX2 and microsomal PGE synthase-1 (PGES1) gene and its protein expression. The expression of COX1, PGES2, PGES3, and PGF synthase (PGFS) mRNA was not affected by IL1A in the stromal cells. The overall results indicate that 1) the target of IL1A and IL1B for stimulating both PGE2 and PGF2a production is the stromal cells, 2) IL1A is a far more potent stimulator than IL1B on PG production in stromal cells, 3) the stimulatory effect of IL1A on PG production is mediated via the activation of PLA2 and COX2, and (4) IL1A induced PG production by increasing expressions of COX2 and PGES1 mRNAs and their proteins in bovine stromal cells.

Summer heat stress affects prostaglandin synthesis in the bovine oviduct

“…The homogeneity of the epithelial cells was evaluated using immunofluorescence staining for specific markers of epithelial (cytokeratin) and stromal (vimentin) cells as described previously (Malayer & Woods 1998, Tanikawa et al 2008 with our modification. Briefly, oviductal epithelial and endometrial stromal (control) cells were seeded on collagencoated sterile cover glasses in six-well plates at a density of 5.0!10 4 cells/ml.…”

“…Briefly, oviductal epithelial and endometrial stromal (control) cells were seeded on collagencoated sterile cover glasses in six-well plates at a density of 5.0!10 4 cells/ml. The endometrial stromal cells were isolated as described previously (Tanikawa et al 2008). The cells were fixed with 4% (wt/vol) paraformaldehyde (Nacalai Tesque, Inc., Kyoto, Japan) for 10 min 48 h after seeding.…”

Is interleukin-1α a luteotrophic or luteolytic agent in cattle?

“…This cytokine, together with IL1B, also affects bovine CL in vitro by modulating the secretions of both PGE 2 and PGF 2a , depending on the stage of the estrous cycle (Davidson et al 1995, Nishimura et al 2004. However, IL1A is thought to stimulate PGE 2 production more strongly than IL1B in stromal cells of the bovine endometrium (Tanikawa et al 2008). In bovine stromal cells, IL1A induced PGE 2 production by increasing the expressions of PTGS2 and PGE 2 synthase type 1 mRNA and their proteins without any effects on PGF 2a synthase (PGFS) expression (Tanikawa et al 2008).…”

“…Previous results suggest that stromal cells are the target of IL1A and IL1B for stimulating the production of both PGs (Tanikawa et al 2008). The action of IL1 and IL2 on both OXT receptor (OXTR) mRNA expression and endometrial PG production may alter luteolysis (Leung et al 2001).…”

“…The action of IL1 and IL2 on both OXT receptor (OXTR) mRNA expression and endometrial PG production may alter luteolysis (Leung et al 2001). Recent in vitro studies from our laboratory suggest that IL1A plays some role in regulating the PGF 2a to PGE 2 ratio during the estrous cycle, and that this effect is mediated via regulation of PGE synthase (Tanikawa et al 2005(Tanikawa et al , 2008. However, based on in vitro studies, there is no consensus whether IL1A has luteotrophic or luteolytic properties (Betts & Hansen 1992, Leung et al 2001, Tanikawa et al 2005.…”