Assessment of the effect of testosterone on the acrosome reaction of human spermatozoa

Abstract

In the acrosome reaction, the spermatozoon plasma membrane fuses with the outer acrosomal membrane, resulting in the release of the acrosomal content. Several compounds, such as sex steroids, are known to modulate the acrosomal exocytosis. Testosterone regulates various functions in male reproductive physiology; however, little is known about the relationship between testosterone and the acrosome reaction. Thus, our objective was to study the effect of testosterone on the acrosome reaction of human spermatozoa. To evaluate the acrosomal exocytosis, spermatozoa were incubated with testosterone (0.2, 2.0 and 20 nmol l(-1)), progesterone and control medium for 60, 120, 240 and 1440 min. The acrosome reaction was assessed by staining with Hoechst 33258 and fluorescein isothiocyanate-conjugated P. sativum agglutinin lectin. In general, spermatozoa incubated with progesterone had the highest percentage of acrosomal exocytosis. The percentage of acrosome reaction obtained in the three treatments with testosterone differed from that observed for progesterone at 120, 240 and 1440 min (24 h). Additionally, significant differences were found between testosterone (2.0 and 20 nmol l(-1)) and progesterone after 60 min. Differences between control and the three testosterone treatments studied were obtained only at 1440 min. In general terms, these results show that testosterone exerts no inductor effects on the acrosome reaction of human spermatozoa.

Evaluation of morphological criteria of sperm quality before in vitro fertilization and intracytoplasmic sperm injection

“…Apoptotic sperm are differentiated from necrotic using double staining with fluorescein isothiocyanate (FITC)-labeled annexin V and Hoechst 33258 (Collodel et al 2009b, de Vantery Arrighiet al 2009). The number of viable acrosome-reacted sperm can be evaluated by staining with Hoechst 33258 and fluorescein isothiocyanate-conjugated Pisum sativum agglutinin lectin (Vigil et al 2008, Tapia et al 2011, Montjean et al 2012, Vigil et al 2012.…”

Sperm Transport Through the Female Reproductive Tract

“…Dentro de este contexto, se ha reportado que la testosterona genera perturbaciones menores en la fluidez de las membranas externa y plasmática del acrosoma, viéndose impedida la fusión de membranas (Shivaji & Jagannadham, 1992). Lo anterior está de acuerdo con nuestros estudios (Vigil et al, 2012a), en los cuales se ha observado que concentraciones fisiológicas de testosterona ejercen un efecto inhibitorio sobre la exocitosis acrosomal del espermatozoide humano.…”

Occurrence and reproductive roles of hormones in seminal plasma

“…Besides progesterone, other steroid hormones are present in both the female reproductive tract and in seminal plasma, and contribute to modulation the above processes [ 9 ]. Some in vitro studies have been undertaken to understand the effects of steroid sex hormones: human spermatozoa were incubated with testosterone [ 10 ] or estradiol [ 11 ], and the acrosome reaction was assessed by staining with Hoechst 33,258 and fluorescein isothiocyanate-conjugated P. sativum agglutinin lectin. While no convincing effect of testosterone was found [ 10 ], estradiol acted as an inhibitor [ 11 ].…”