Insulin-like growth factor-II stimulates human granulosa-luteal cell proliferation in vitro

To determine the effect of insulin-like growth factor-II (IGF-II) on human granulosa cell proliferation in vitro.

Thymidine incorporation and cell count were determined to assess human granulosa cell proliferation.

The study was performed in an academic research environment.

Granulosa cells were obtained from women undergoing IVF procedures.

Granulosa cells were dispersed enzymatically and cultured in both serum-containing and serum-free medium.

Granulosa cell proliferation in basal conditions and after stimulation with IGF-II given alone or in combination with basic fibroblast growth factor (basic FGF).

Treatment of human granulosa cells with IGF-II for 24 hours significantly increased thymidine incorporation. Furthermore, this mitogenic effect was confirmed when granulosa cells were cultured in presence of IGF-II for 7 to 10 days and their proliferation was evaluated by cell counting. The association of IGF-II and basic FGF did not result in a synergistic or additive effect.

As already demonstrated in other species, IGF-II also is able to stimulate human granulosa cell proliferation in vitro. Thus, it might be considered among the intraovarian modulators of granulosa cell physiology.