INTERLEUKIN-1-ALPHA, EPIDERMAL GROWTH-FACTOR, AND TRANSFORMING-GROWTH-FACTOR-BETA EXHIBIT DIFFERENTIAL KINETICS ON ENDOTHELIN-1 SYNTHESIS IN AMNION CELLS

OBJECTIVE: To investigate the effects of three cytokines, interleukin- 1 alpha (IL-1 alpha), epidermal growth factor (EGF), and transforming growth factor-beta (TGF-beta), on the regulation of endothelin-1 (ET-1 ) mRNA and protein production in human amnion cells. METHODS: Human am nion cells were harvested from uncomplicated pregnancies undergoing el ective cesarean delivery at term and grown in primary monolayer cultur e. Cells were treated with IL-1 alpha, EGF, and TGF-beta for dose-resp onse and time course experiments. Northern analysis was used to determ ine ET-1 mRNA expression, and enzyme-linked immunosorbent assay was us ed for ET-1 peptide determination. RESULTS: Interleukin-1 alpha, EGF, and TGF-beta induced the expression of ET-1 mRNA and protein in a dose - and time-dependent fashion. This kinetics of ET-1 mRNA production di d not differ markedly with respect to the inducing cytokine, but the k inetics of ET-1 protein production was quite different. Interleukin-1 alpha and EGF stimulated a rapid increase in ET-1 that peaked by 24 ho urs, and the levels declined to just above the detection limit by 72 h ours. In contrast, TGF-beta-stimulated cells showed modest ET-1 produc tion at early times (4-24 hours) and then gradually increased and peak ed at 72 hours. CONCLUSIONS: Cytokines modulate the expression of ET-1 mRNA and its cognate protein in human amnion cells. The differential kinetics of ET-1 peptide expression in amnion cells suggests that ET m etabolism as well as synthesis contribute to the net expression of end othelin in amnion. Copyright (C) 1998 by the Society of Gynecologic In vestigation.