Transforming Growth Factor-alpha Regulation of Insulin-like Growth Factor-II, Insulin-like Growth Factor Binding Protein-1 and 3 secretion and Epidermal Growth Factor receptor expression in human luteinized granulosa cells / 대한산부인과학회잡지

ABSTRACT

OBJECTIVE: To investigate the effects of transforming growth factor (TGF)-alpha on insulin-like growth factor (IGF)-II, insulin-like growth factor binding protein (IGFBP)-1, and 3 secretion and epidermal growth factor (EGF) receptor expression in cultured human luteinized granulosa cells. MATERIALS AND METHODS: Human luteinized granulosa cells were obtained from follicular fluid by transvaginal oocyte aspiration from infertile patients undergoing in vitro fertilization and cultured for 72 hours with TGF-alpha at concentration of 1.0, 10.0, 100.0 ng/ml. The luteinized granulosa cells not treated with TGF-alpha served as control. The secretion of IGF-II, IGFBP-1 and 3 were determined in conditioned media by immunoradiometric assay (IRMA) and reverse transcription-polymerase chain reaction (RT-PCR) was performed for EGF receptor mRNA expression. RESULTS: The cell numbers of 1.0 and 10.0 ng/ml supplement groups were significantly decreased compared to control (p<0.05, p<0.05, respectively), although the cell viabilities were similar in all groups. IGF-II levels were significantly higher in TGF-alpha treatment group at 1.0 and 10.0 ng/ml (p<0.01, p<0.01, respectively), but lower in 100.0 ng/ml (p<0.01). However, the concentrations of IGFBP-1, and 3 per one granulosa cell in each group were no statistically significant differences among the groups. The mRNA concentration of EGF receptor in cultured human luteinized granulosa cells were not significantly different among the groups. CONCLUSION: This study suggests that TGF-alpha regulate intrafollicular bioavailable IGF-II levels, by which TGF-alpha might involved luteinizations. However, TGF-alpha may not directly regulate EGF receptor mRNA expression in cultured human luteinized granulosa cells.