Effect of Lead on Human Blood Antioxidant Enzymes and Glutathione

Abstract

Human exposure to lead may alter the enzyme antioxidants level and the interaction between antioxidants and blood lead level (BLL) eventually cause oxidative stress. Therefore, the present investigation was carried out to establish the relationship between the antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and antioxidant molecule reduced glutathione (GSH) with varying BLLs. A randomly selected 250 subjects from rural-urban populations of either sex ranging in age from 20 to 70 years were investigated. The mean value of BLL in 250 subjects was 15.16±11.82 μg/dl with a minimum level of 0.1 μg/dl and the maximum level of 39.71 μg/dl. Pearson’s linear correlation analyses were used to evaluate the influence of BLL on the enzyme antioxidants. Significant modulation of enzymes antioxidants on BLLs and characteristics of demographic data such as habits, substances abuse (smoking effect), sex and diet of rural-urban population were observed in present investigation. The urban population, non-vegetarians, males and smokers had higher blood lead levels. The BLL was negatively correlated with the activity of SOD, CAT, GPx and GSH. Increased BLLs and statistically significant decreased activity of enzyme antioxidants might contribute to lead-induced toxicity in urban population. These findings suggest a rationale for lowering the enzyme antioxidants with decreasing BLLs.