Relationship between indicators of oxidative stress and idiopathic infertility in men

Abstract

Male infertility is a major health problem worldwide. According to a study of the WHO and the European Association of Urologists, the incidence of infertility is increasing worldwide. The male factor causes up to 50% of all cases of infertility in married couples and approximately 7% of men worldwide suffer from infertility. No cause can be found in approximately 30% of infertile men, and these cases are called idiopathic infertility. In many such cases, oxidative stress is believed to be the main causative factor. Oxidative stress, which is characterized by an imbalance between the production of reactive oxygen species and the antioxidant defense system, which is responsible for their neutralization, leads to damage to many cellular structures, especially phospholipids of cell membranes. The study is aimed at studying the adverse effect of lipid peroxidation on spermatogenesis in idiopathic male infertility. The study was conducted on the sperm of 56 men with normozoospermia and 30 men with oligoasthenozoospermia. The levels of malondialdehyde, zinc, fructose, NO-synthase activity and glutathione peroxidase (GP) in seminal plasma were correlated with sperm count and motility. Ejaculate malondialdehyde and NO-synthase activity were significantly higher, while zinc, fructose and GP were significantly lower in oligoasthenospermic than in normospermic men (p<0.001). A 1.8-fold decrease in the level of fructose in the spermogram of patients of group oligoasthenospermia, compared to the data of normozoospermic men correlated with processes of impaired motility and viability of spermatozoa. This was confirmed by the data obtained in the scientific work, in the form of a statistically significant difference in the average indicator of the quantitative content of fructose in the studied groups of patients. In particular, we found a positive correlation between the fructose content in the ejaculate and sperm motility (r=0.69), as well as a positive correlation between fructose content and the number of spermatozoa in the ejaculate (r=0.53). There was a significant negative correlation between malondialdehyde and NO-synthase with sperm count and motility in oligoasthenospermia. Elevated levels of malondialdehyde, NO-synthase in sperm, and decreased levels of zinc and GP in oligoasthenospermia may be responsible for impaired sperm membrane integrity and play a role in sperm DNA damage. The positive correlation of zinc with sperm count and sperm motility indicates an important role of zinc in spermatogenesis. Thus, these parameters may be useful in determining the fertilization potential of sperm in the diagnosis, prognosis and treatment of male infertility, especially idiopathic infertility.

Keywords: sperm plasma, malondialdehyde, glutathione peroxidase, NO-synthase, zinc, fructose.