Expression of Androgen Receptor and 5-Alpha Reductase in the Endometrium of Infertile Women With Endometriosis

Abstract

Previous studies have suggested that pelvic endometriosis is severer in hyperandrogenic women compared to normoandrogenic women. The aim of this study was to evaluate whether subclinical alterations in the bioavailability and/or sensitivity to androgens would be associated to endometriosis. This was an open, prospective, controlled study involving 34 infertile women who underwent laparoscopy and were divided into 2 groups: control (n=19) and endometriosis (n=15) according to the histological and laparoscopic findings. Endometrial and endometriotic implant biopsies were performed. Serum testostereone, SHBG and insulin levels were measured. RT-PCR analysis and immunohistochemistry were carried out to detect the presence of the androgen receptor and type 1 5α-reductase (5α-R1) gene message and protein expression, respectively. No statistically significant differences were observed between the two groups when anthropometric measurements and testosterone, SHBG or insulin concentrations were analyzed. 5α-R1 mRNA and AR mRNA and protein were present in the intrauterine endometria of both groups, as well as in the pelvic implants of the endometriosis group. The same topographic distribution of AR and mRNA abundance for AR and 5α-R1 were observed regardless of the study group or the tissue being eutopic or ectopic. Infertile women with endometriosis do not appear to be more exposed to circulating testosterone nor to androgen stimulation at the endometrium compared to other infertile women without evidence of endometriosis.