Relationship between Fertilin _ mRNA expression and the fertilizing potentials of human spermatozoa

Abstract

Fertilin is a sperm surface protein that belongs to the ADAM (a disintigrin and a metalloproteinase) family of integral membrane proteins. It mediates adhesion and fusion between the sperm and egg plasma membranes that may play important roles in mammalian fertilization. This study aimed to explore the relation between fertilization ability of human sperm and fertilin mRNA expression in non-fertile men. Expression of fertilin gene mRNA was determined by RT-PCR from 141 semen samples (infertile n=81 and normal fertile n=60 men). Total RNA was extracted from sperm pellets. cDNA was generated then amplified. Computer assisted semen analysis and acrosine activity test were also performed. ELISA was done to measure FSH, LH, testosterone and prolactin. The study showed lowered sperm fertilin expression in infertile group together with decreased sperm motility and other sperm functions. Also, there was significant positive correlation between fertilin expression and testosterone levels. Furthermore, normal morphology may influence changes of fertilin as shown by multiple regression analysis. From this study it can be concluded that infertility which is associated with decreased expression of sperm fertilin could be due to failure of sperm migration into the oviduct. Moreover, defective protease can produce incomplete fertilin processing with improper maturation of sperm proteins. Here in this study showed possible direct role of fertilin- in fertilization and also in sperm morphology and hence sperm capicitation.

Keywords: Fertilin expression, Infertility, Hormonal profile, Sperm function.