Tumor necrosis factor-alpha alters steroidogenesis and stimulates proliferation of human ovarian granulosal cells in vitro.

OBJECTIVE

To determine if tumor necrosis factor alpha (TNF-alpha) altered human granulosa-luteal cell proliferation and steroidogenesis.

DESIGN

Aspirates of follicles from women undergoing in vitro fertilization were subjected to Percoll gradients to collect an enriched population of granulosa-luteal cells. The granulosa-luteal cells were subjected to culture for a period of 10 or 20 days in the presence or absence of various doses of human recombinant TNF-alpha (0.1 to 10.0 ng/mL).

PATIENTS

Granulosa-luteal cells from nine patients were evaluated for their response to TNF-alpha in vitro. Patients with three follicles > 16 mm and a serum estradiol (E2) concentration of > 1,836 pmol/L were selected for study.

RESULTS

Tumor necrosis factor-alpha increased granulosa-luteal cell number. By day 10 of culture, 10 ng TNF-alpha/mL doubled cell number and > 95% of the cells exhibited 3 beta-hydroxysteroid dehydrogenase. Tumor necrosis factor-alpha at 10 ng/mL increased progesterone (P) accumulation from day 4 through day 20 of culture. Tumor necrosis factor-alpha also increased E2 secretion but in a biphasic manner. During the first 14 days of culture, TNF-alpha increased E2, but thereafter E2 decreased to basal values by day 20. When steroidogenesis was expressed per 1,000 cells per days of culture, TNF-alpha did not increase P beyond controls but significantly increased E2 for the first 14 days of culture after which E2 per 1,000 cells declined.

CONCLUSIONS

The results indicate that TNF-alpha stimulates granulosal-luteal cell growth and E2 secretion in vitro, and thus TNF-alpha may promote cellular events associated with formation of the corpus luteum; i.e., granulosa-cell proliferation and steroidogenesis.