Aberrant expression of the endocannabinoid system in spermatozoa from asthenozoospermic patients

PEREZ-MARTÍNEZ, SILVINA; ARENAS, G.; MARTÍNEZ, EDUARDO; REY, R.; BURDET, J.

Montreal

Congreso; Society for Study of Reproduction SSR 46th Annual meeting; 2013

Society for Study of Reproduction (SSR)

Aberrant asthenozoospermic patients expression of the endocannabinoid system in spermatozoa from 1 1 2 1 2 1 Burdet Juliana, , Arenas Gabriela, Martínez Eduardo, Rey Valzacchi Gastón and Perez Martinez Silvina. 1 Laboratorio de Biología de la Reproducción en Mamíferos CEFyBO ? CONICET; Centro de reproducción asistida PROCREARTE. 2 Male infertility is a major cause of problems for many couples when conceiving a child. As one of the important factors that cause infertility, asthenospermia is characterized as low sperm motility. The endocannabinoid system, mainly through the action of anandamide (AEA) at cannabinoid (CB1, CB2) and vanilloid (TRPV1) receptors, plays a crucial role in controlling functionality of sperm, with a clear impact on male reproductive potential. Endocannabinoids are lipid mediators that mimic the effects of cannabinoids. Their effects depend on the concentration in the extracellular space, which is controlled principally by its degrading enzyme: fatty acid amide hydrolase (FAAH). In mice, FAAH deficiency (FAAH-/ -) increases AEA levels in the reproductive tract and reduces sperm motility and its ability to fertilize an egg. The aim of this study was to characterize FAAH enzyme and TRPV1 receptor in patients affected by idiopathic asthenozoospermia. Spermatozoa normozoospermic donors (Normo) were selected by glass wool. To characterize FAAH and TRPV1 proteins, Western blot and indirect immunofluorescence assays were performed using specific anti-FAAH and anti-TRPV1 antibodies. Results showed no significant differences in FAAH protein expression between Normo and Astheno. However, FAAH immunolocalization was different in these groups. In Normo, FAAH enzyme was mainly localized in the post-acrosomal region and mid-piece of the tail (66 %). In Astheno, FAAH localization varied between: a) post-acrosomal region and mid- piece of the tail (38%), b) mid-piece of the tail (10%) and c) acrosome region and end piece of the tail (52%). Interestingly, a decrease in FAAH activity was observed in Astheno compared to Normo. Furthermore, a significant decrease of TRPV1 protein expression was detected in Astheno patients (p<0.05). TRPV1 immunolocalization was observed along the sperm tail both in Normo and Astheno. However, the percentage of immnodetection in Astheno was lower than in Normo (15% vs 68%, respectively; p<0.001), according to western blot results. Asthenozoospermia is a common cause of male infertility. Its etiology probably includes a series of biochemical and functional defects, among which a deregulation of the endocannabinoid system may be involved. Different FAAH enzyme location and a decrease in TRPV1 expression suggest that aberrant endocannabinoid system may be involved sperm motility failure of astenoszoopermic patients.