Effect of lipopolysaccharide and cytokines on synthesis and secretion of leukotrienes from endometrial epithelial cells of pigs

In the present study, effects were studied of lipopolysaccharide (LPS), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-4 and IL-10 on the mRNA and protein expression of 5-lipooxygenase (5-LO), leukotriene (LT)A4 hydrolase (LTAH) and LTC4 synthase (LTCS), and secretion of LTB4 and LTC4 from endometrial epithelial cells of pigs, as well as on viability of these cells. Cells were incubated for 24 h with LPS (10 or 100 ng/ml of medium), TNF-α, IL-1β, IL-4 or IL-10 (each cytokine: 1 or 10 ng/ml of medium). Larger doses of TNF-α and IL-10 and both doses of IL-1β increased the relative abundance of mRNA/protein of 5-LO in the cells. A similar effect was exerted by the smaller dose of LPS on 5-LO mRNA content. Smaller doses of LPS and IL-4, and the larger dose of IL-10 increased the relative abundance of mRNA/protein LTAH, while both doses of TNF-α and the larger dose of IL-1β increased the protein content of this enzyme. Relative abundance of the mRNA/protein of LTCS was greater with the smaller dose of LPS, both doses of TNF-α and greater doses of IL-1β and IL-10, while relative abundance of LTCS mRNA was greater in response to the larger dose of LPS and both doses of IL-4. The LTB4 and LTC4 release was increased by the smaller dose of LPS, both doses of TNF-α and larger doses of IL-1β and IL-10. The IL-4 at the smaller dose exerted a stimulatory effect on LTB4 release. Larger doses of TNF-α and IL-4 enhanced cell viability. Interactions with LPS and cytokines revealed in this study may represent mechanisms important for the regulation of endometrium functions of pigs under physiological or pathological conditions.