Seminal Malondialdehyde Concentration And Superoxide Dismutase, Catalase Activity In Male Infertility

摘要

Aims & objectives- Reactive oxygen species (ROS) induced lipid peroxidation is associated with sperm function. Malondialdehyde (MDA) concentration, Superoxide dismutase and Catalase (CAT) activity represent the lipid peroxidation and spermicidal antioxidant status respectively. The present study aimed to evaluate the relationship of MDA, Superoxide dismutase and Catalase levels with sperm parameters. Materials & methods-Specimens were divided into two groups: Group I - Normospermia (n=30); Group II - Oligoasthenozoospermia (n=30). Seminal MDA concentration was measured by thiobarbituric acid reaction method. Seminal SOD activity was measured by Marklund and Marklund method. Seminal Catalase activity was measured by potassium dichromate colorimetric assay. Seminal MDA levels, SOD and Catalase activities in both groups were compared. Significance of the data is analyzed using unpaired t-test. Results - MDA concentrations in both groups were significantly different (12.65 ± 1.68 nmole/m vs 21.58 ± 1.54 nmole/ml). SOD & Catalase activities in both groups were also significantly different. SOD levels in oligoasthenozoosperia were 27.99 ± 4.36 Units/ml and in normospermia 12.96 ± 3.35 U/ml whereas levels of catalase in oligiasthenozoosperia were 1.36 ± 0.44 Units/mg of protein and normospermia were 5.12 ± 1.03 Units/mg of protein. SOD & Catalase activities were positively and significantly correlated with the sperm concentration and sperm motility. Conclusion : Measurement of seminal MDA concentrations, antioxidant enzymes SOD & CAT can be used as a additional, simple and useful tool in predicting quality of sperm parameters. Introduction Infertility has been a major medical problem as well as social stigma. Despite of enormous progress in research, most of the blame for infertility is placed on the female. Advances in understanding of gonadal/sperm physiology have increased our knowledge of male infertility. Defective sperm function is the most prevalent cause of male infertility. [1]. Many environmental, physiological, and genetic factors have been implicated in infertility. Hence, it is very important to identify factors, which affect normal sperm function. Free radical-induced oxidative damage to spermatozoa is a condition, which is gaining considerable attention for its role in inducing poor sperm function [2]. Understanding of such conditions will help in designing new and effective treatment strategies.Until recently, Reactive oxygen species (ROS), were considered toxic to the human spermatozoa. However a strong evidence suggests that small amounts of ROS are necessary for spermatozoa to acquire fertilizing capabilities [3], [4],[5]. Theoretically, cellular damage in the semen is due to improper balance between ROS generation and scavenging activities which causes ‘Oxidative stress’.The increased ROS formation leads to lipid peroxidation. This is correlated with reduced sperm motility [6], [7], due to decrease in axonemal protein phosphorylation and sperm immobilization, both of which are associated with a reduction in membrane fluidity [8]. Another hypothesis is that H2O2 can diffuse across the cell membranes and inhibit the activity of enzyme, glucose-6-phosphate dehydrogenase (G6PD). Inhibition of G6PD decreases the availability of NADPH and results in accumulation of oxidized glutathione, which reduces the antioxidant defense of the spermatozoa [9].The seminal plasma is well endowed with an array of antioxidants such as Superoxide dismutase (SOD), Catalase. These antioxidants protect spermatozoa against oxidative stress [10],[11],[12]. SOD scavenges superoxide anion and converts it into less potent hydrogen peroxide. Catalase detoxifies H2O2 to water and oxygen [13] This study was undertaken to correlate detrimental effect of free radicals on sperm physiology in infertile males. The prime aim of the study was to estimate the lipid peroxidation product; MDA & some antioxidants in men with oligoasthenozoospermia compared to