PROBLEM: Prostaglandins (PGs) are synthesized in the endometrium. Our objective was to evaluate interleukin (IL)-1α-induced production of PGE2 and PGF2α in endometrial stromal cells (ESC) following treatment with ceramide analogues.
METHODS OF STUDY: ESC were obtained from human uterine endometrium by enzymic digestion and filtration. ESC were treated with IL-1α, IL-1 receptor antagonist (ra), C2-ceramide and C6-ceramide. The concentrations of PGE2 and PGF2α in media were determined using ELISA. The induction of prostaglandin H synthase (PGHS)-2 mRNA was also ascertained by reverse transcription-polymerase chain reaction (RT-PCR).
RESULTS: The production of PGE2 and PGF2α was significantly increased by IL-1α and suppressed by IL-1 ra, in a dose-dependent manner. PGF2α production was further increased by treatment with the combination of IL-1α and C2-ceramide as compared with IL-1α treatment alone. There was no significant difference in PGE2 production between cells treated with IL-1α and C2-ceramide and those treated with IL-1α alone. Both PGE2 and PGF2α production were significantly increased by treatment with IL-1α and C6-ceramide as compared with IL-1α treatment alone. Treatment of ESC with IL-1α stimulated PGHS-2 mRNA. PGHS-2 mRNA was decreased when IL-1 ra was added to the IL-1α-stimulated cells.
CONCLUSIONS: These results suggest that IL-1α stimulates the production of PGE2 and PGF2α by a mechanism that involves the sphingomyelin-ceramide system, and thus that ceramide may be important in increasing the production of PGE2 and PGF2α in the human endometrium.