Table of Contents
ISRN Obstetrics and Gynecology
Volume 2014, Article ID 818010, 11 pages
http://dx.doi.org/10.1155/2014/818010
Review Article

The Role of Androgen Hormones in Early Follicular Development

Sector of Human Reproduction, Department of Gynecology & Obstetrics, Ribeirão Preto Medical School, University of São Paulo, Avenida Bandeirantes, 3900 Ribeirão Preto, SP, Brazil

Received 19 December 2013; Accepted 18 February 2014; Published 10 April 2014

Academic Editors: R.-C. Chian, N. A. Ginsberg, S. Palomba, and C. J. Petry

Copyright © 2014 Catiele Garcia Gervásio et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Background. Although chronic hyperandrogenism, a typical feature of polycystic ovary syndrome, is often associated with disturbed reproductive performance, androgens have been shown to promote ovarian follicle growth in shorter exposures. Here, we review the main effects of androgens on the regulation of early folliculogenesis and the potential of their application in improving follicular in vitro growth. Review. Androgens may affect folliculogenesis directly via androgen receptors (ARs) or indirectly through aromatization to estrogen. ARs are highly expressed in the granulosa and theca cells of early stage follicles and slightly expressed in mature follicles. Short-term androgen exposure augments FSH receptor expression in the granulosa cells of developing follicles and enhances the FSH-induced cAMP formation necessary for the transcription of genes involved in the control of follicular cell proliferation and differentiation. AR activation also increases insulin-like growth factor (IGF-1) and its receptor gene expression in the granulosa and theca cells of growing follicles and in the oocytes of primordial follicles, thus facilitating IGF-1 actions in both follicular recruitment and subsequent development. Conclusion. During the early and intermediate stages of follicular maturation, locally produced androgens facilitate the transition of follicles from the dormant to the growing pool as well as their further development.