Importance of the assessment of coenzyme Q10, alpha-tocopherol and oxidative stress for the diagnosis and therapy of infertility in men

Abstract

Male infertility is one of the most stressful factors of couples, being present in about 40% cases. It is usually caused by a low number of sperm (oligozoospermia) or poor sperm motility (asthenozoospermia). The sperm motility is used as an indicator of semen quality and male infertility. To the impairment of male reproduction health can contribute genetic, nutritional and environmental factors, smoking and drugs. It is well documented that excessive reactive oxygen species (ROS) production decreases sperm motility, impairs sperm function, damages the morphology of spermatozoa (1, 2). To the decreased sperm motility contribute also disturbances of sperm mitochondrial function and energy production, low levels of coenzyme Q10 and carnitine, as well as sperm mitochondrial deoxyribonucleic acid (DNA) defects. The origin of sperm dysfunction, however, is not well understood. Oxidative stress has been established as a major factor in the pathogenesis of male infertility. Low level of coenzyme Q10 contributes to the decreased sperm motility, which plays a vital role in sperm mitochondrial energy production and neutralization of reactive oxygen species (ROS).The aim of the present study was to find out, if an assessment of coenzyme Q10-TOTAL (CoQ10-TOTAL), α-tocopherol, γ-tocopherol and oxidative stress could contribute to the diagnosis of infertility in men. Two groups of infertile men, according to sperm motility (a+b and b+c) were included in the study. CoQ10-TOTAL, α-tocopherol, γ-tocopherol in plasma and seminal fluid, and parameter of oxidative stress (thiobarbituric acid reactive substances - TBARS) in plasma were determined. Higher sperm density and decreased sperm pathology were found in group a+b vs b+c (class a and b - fast and weak forward motility, class c - nonprogressive motility). Concentrations of CoQ10-TOTAL and α-tocopherol were significantly increased in seminal fluid of groups a+b vs b+c, opposite results were estimated in plasma. Concentrations of γ-tocopherol in plasma and seminal fluid of both groups were similar. Plasmatic TBARS concentrations were increased in both groups of infertile men. We suppose that incorporation of oxidative stress assessment, CoQ10-TOTAL and α-tocopherol concentrations in seminal fluid and plasma into routine andrology can play an important role for the diagnosis and targeted therapy of male infertility (Tab. 1, Ref. 16).