ALTERED DISTRIBUTION OF MANNOSE 6-PHOSPHATE RECEPTORS IN RAT SPERMATOZOA DUE TO CASTRATION

PULCINI G ; AGUILERA AC; SOSA MA; CARVELLI L

San Juan

Congreso; San Juan; 2023

Sociedad de Biologia de cuyo

In somatic cells, both cation-independent and cation-dependent mannose 6-phosphate receptors (CI-MPR and CD-MPR) play crucial roles in delivering acid hydrolases to lysosomes. Our prior laboratory findings have demonstrated the presence of both CI-MPR and CD-MPR on the plasma membrane of epididymal rat spermatozoa. As sperm undergo maturation during their transit through the epididymal duct, MPRs exhibit dynamic changes in their distribution. Notably, their location undergoes a significant shift after the acrosomal reaction, suggesting a potential connection to the process of sperm maturation. Considering that the epididymis is a steroid hormone-dependent organ, our study aimed to evaluate the impact of testosterone deprivation on the distribution of MPRs in rat spermatozoa. Through indirect immunofluorescence, we observed a redistribution of CD-MPR and CI-MPR in spermatozoa from the epididymal caput of castrated animals when compared to control groups. This redistribution pattern closely resembles that of capacitated and acrosome-reacted spermatozoa obtained from the cauda epididymis. The shift in MPRs distribution due to androgen deprivation may indicate potential alterations in membrane composition and early sperm capacitation. These changes may be attributed to a decrease in the levels of estrogenic sulfotransferase in castrated rats (confirmed by immunoblot), which typically inhibit acrosomal proteolytic enzymes like acrosin, an essential component of sperm training and fertilization. Exploring the hormonal regulation mechanism of sperm maturation provides valuable insights into reproductive health.