Pigment epithelium-derived factor exerts antioxidative effects in granulosa cells.

Objective: To determine whether supplementing granulosa cells cultures with pigment epithelium-derived factor (PEDF) can protect them from oxidative stress.

Design: We used either granulosa cell line or human primary granulosa cell culture from women undergoing in vitro fertilization (IVF) treatments.

Setting: University research facilities.

Animal(s): Imprinting control region female mice.

Intervention(s): Recombinant PEDF (rPEDF) was added to cultures of either primary granulosa cell culture or granulosa cell line in the present or absence of H2O2 triggering.

Main Outcome Measure(s): We followed cell viability with the use of methylthiazolyl tetrazolium assay and tracked PEDF mechanism of action with the use of Western blot analysis, measuring the level of SOD-1 and GPX-1 mRNA, protein level of BAX, and phosphorylation of AKT.

Result(s): We found that granulosa cell viability and the level of PEDF mRNA were both significantly reduced, in a dose-dependent manner, after exposure to H2O2. The rate of H2O2-induced apoptosis was significantly attenuated in granulosa cells treated with rPEDF. We showed that granulosa cells, of both humans and rodents, express the PEDF receptor, PNPLA2; once stimulated by rPEDF, the cells exhibited phosphorylation of AKT. Finally, we showed that PEDF exerts its antioxidative activity through the AKT signaling pathway.

Conclusion(s): This study demonstrates that PEDF represents a novel intrinsic antioxidant of granulosa cells.