[Effect of lipopolysaccharide on cyclooxygenase-2 expression and prostaglandin E2 release in human nasal epithelia]

To detect cyclooxygenase-2 (COX-2) expression and prostaglandin E2 (PGE2) release in human nasal epithelia (HNE) induced by lipopolysaccharide (LPS) in different concentration gradient and time gradient, and to investigate their roles in nasal inflammatory pathogenesis.

Western Blot and fluorescent real time quantitative PCR were performed to detect the expression of COX-2 in HNE induced by LPS and blocked by selective inhibitor of COX-2. The concentrations of PGE2 were determined by enzyme immunoassay.

Low expressions of COX-2 and PGE2 were detected in normal HNE. COX-2 expression and PGE2 release increased in HNE induced by LPS in time-dependent or dose-dependent manner. The increased release of PGE2 was later than that of COX-2 expression. COX-2 expression and PGE2 release were dose-dependently attenuated by selective inhibitor of COX-2.

LPS effectively induces COX-2 expression and PGE2 release in HNE. And COX-2 is responsible for the synthesis of PGE2. These results indicate that the increased expression of COX-2 and PGE2 is involved in the inflammation of HNE induced by LPS in vitro.