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Oestrogens as apoptosis regulators in mammalian testis: angels or devils?

Published online by Cambridge University Press:  27 January 2015

Sara Correia
Affiliation:
CICS-UBI, Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
Henrique J. Cardoso
Affiliation:
CICS-UBI, Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
José E. Cavaco
Affiliation:
CICS-UBI, Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
Sílvia Socorro*
Affiliation:
CICS-UBI, Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
*
*Corresponding author: Sílvia Socorro, CICS-UBI - Health Sciences Research Center, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal. E-mail: [email protected]

Abstract

In the mammalian testis, spermatogenesis is a highly coordinated process of germ cell development, which ends with the release of ‘mature’ spermatozoa. The fine regulation of spermatogenesis is strictly dependent on sex steroid hormones, which orchestrate the cellular and molecular events underlying normal development of germ cells. Sex steroids actions also rely on the control of germ cell survival, and the programmed cell death by apoptosis has been indicated as a critical process in regulating the size and quality of the germ line. Recently, oestrogens have emerged as important regulators of germ cell fate. However, the beneficial or detrimental effects of oestrogens in spermatogenesis are controversial, with independent reports arguing for their role as cell survival factors or as apoptosis-inducers. The dual behaviour of oestrogens, shifting from ‘angels to devils’ is supported by the clinical findings of increased oestrogens levels in serum and intratesticular milieu of idiopathic infertile men. This review aims to discuss the available information concerning the role of oestrogens in the control of germ cell death and summarises the signalling mechanisms driven oestrogen-induced apoptosis. The present data represent a valuable basis for the clinical management of hyperoestrogenism-related infertility and provide a rationale for the use of oestrogen-target therapies in male infertility.

Type
Review Article
Copyright
Copyright © Cambridge University Press 2015 

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