Background: The aim of the present study was to evaluate the effect of GnRH analogues on the in-vitro eutopic endometrial cell apoptosis and release of interleukin-1beta (IL-1beta) and vascular endothelial growth factor (VEGF).
Methods: Biopsy specimens of eutopic endometrium obtained from 16 women with untreated endometriosis and 14 controls were studied. Apoptosis, IL-1beta and VEGF release were evaluated in epithelial endometrial cell cultures after incubation with leuprolide acetate (LA) as GnRH agonist, antide as GnRH antagonist, and a combination of both. The percentage of apoptotic cells was evaluated by the acridine orange-ethidium bromide technique, and IL-1beta and VEGF concentrations were assessed by using commercial enzyme-linked immunosorbent assay (ELISA) kits.
Results: We found that LA (100 ng/ml) enhanced apoptosis in endometrial cell cultures from endometriosis patients and controls and this effect was reversed by antide at 10(-7) mol/l. IL-1beta and VEGF release was downregulated by LA in cultures from controls and endometriosis patients. The addition of antide 10(-7) mol/l reversed this inhibition. Endometrial cultures treated with antide at 10(-7) mol/l did not show any significant effects compared with basal conditions.
Conclusions: GnRH agonists appear to have a direct effect in endometrial cells cultures, by enhancing the percentage of apoptotic cells and decreasing the release of pro-mitogenic cytokines such as IL-1beta and VEGF.