Effect of Aromatase Inhibitors on VEGF and PGE2 levels in the peritoneal fluid in a murine model of endometriosis

BILOTAS M; MERESMAN GF; SUELDO C; BARAÑAO RI

Huerta Grande, Córdoba, Argentina

Congreso; I Reunión conjunta de Sociedades de Biología de la República Argentina; 2007

It has been demonstrated that Aromatase P450 enzyme is expressed in the eutopic and ectopic endometrium of patients with EDT and that VEGF and PGE2 levels are increased in the PF of these patients. Recently it has been proposed that VEGF and PGE2 would be involved in a positive feedback loop that would promote the local estrogen synthesis produced by Aromatse P450 inside the endometriotic lesions (EL). The AI, Letrozole (L) and Anastrozole (A), are being evaluated as a therapeutic alternative to EDT treatment. The aim of this work was to evaluate the effect of AI on the EL growth and the VEGF and PGE2 levels in the PF in a murine model of EDT. After four weeks from EDT induction, mice were treated with a diary s.c. injection of A, L or saline (Control, C) during another four weeks. At the end of the treatment mice were sacrificed and the lesions were counted and measured. The PF was collected and assayed for VEGF and PGE2 levels by ELISA and RIA respectively. The treatment did not cause EL regression but diminished EL size significantly (p<0.05 vs. C). As well, A and L diminished VEGF levels in the PF (p<0.05 vs. C). Nevertheless, only the treatment with L caused a significant decrease on PGE2 levels in PF (p<0.001) whereas A did not cause any significant change. Our results suggest that AI has a beneficial effect on EL growth and supports further investigation of AI as a possible treatment for EDT.