Catalase and Superoxide Dismutase Activities as Biomarkers of Oxidative Stress in Workers Exposed to Mercury Vapors

Abstract

For this article we investigated the role of three blood antioxidant enzyme activities and total antioxidant status (TAS) as biological markers of oxidative stress in workers exposed to mercury (Hg(o)) vapors. Twenty-two female workers took part in the study. The examination included a questionnaire on age, educational level, occupational history, actual health status, previous accidents and diseases, smoking and dietary habits, and alcohol consumption. Blood and urine sampling for biological analyses completed this examination. The workers were classified into three subgroups according to their creatinine-corrected Hg concentration in urine. Blood antioxidant enzyme activities and TAS were compared between groups with nonparametric distribution-free methods. A significant difference existed in catalase activity and a slight, but not significant, difference existed in Cu2+/Zn2+ superoxide dismutase (Cu2+/Zn2+ SOD) activity between the three groups. No differences were observed in either the glutathione peroxidase activity or the TAS between these groups. Catalase and Cu2+/Zn2+ SOD activities were increased in the groups of workers with higher creatinine-corrected urinary Hg concentrations when compared with the group of lower creatinine-corrected urinary Hg concentrations. Catalase activity was positively correlated with the creatinine-corrected concentration of Hg in urine, and Cu2+/Zn2+ SOD activity was slightly correlated with the creatinine-corrected concentration of Hg in urine. The role of erythrocyte catalase and Cu2+/Zn2+ SOD activities we have measured is in agreement with the hypothesis of the involvement of reactive oxygen species production as an important event in chronic exposure to Hg(o) vapors in humans. In spite of the small size of the sample, these results indicate that erythrocyte catalase and Cu2+/Zn2+ SOD activities could be considered as markers of biological effect in workers exposed to Hg(o) vapors.

Enzymatic Antioxidants in Erythrocytes Following Heavy Metal Exposure: Possible Role in Early Diagnosis of Poisoning

“…1991). Recently, Perrin-Nadif et al (1996) reported altered blood SOD and catalase in Hg-exposed workers and suggested these enzymes as biomarkers of oxidative stress . Although our investigation has shown dosedependent changes in RBC antioxidant enzymes, further work correlating enzymatic changes with blood metal levels particularly in human subjects exposed to heavy metals is needed in order to validate the possible use of these parameters for an early diagnosis and toxicity evaluation.…”

Relationship between blood antioxidants and occupational exposure to polycyclic aromatic hydrocarbons in coke oven workers

“…Thus, we assessed oxidative stress in workers exposed to oxidants by measuring the blood antioxidant enzyme activities and total plasma antioxidant concentration mentioned above. Recently, we found that erythrocyte catalase and Cu ϩϩ / Zn ϩϩ SOD activities were increased in workers with higher creatinine-corrected concentration of mercury (Hg) in urine when compared with workers with lower creatininecorrected concentration of Hg in urine [Perrin-Nadif et al, 1996b]. Moreover, catalase activity was positively correlated with the urinary creatinine-corrected concentration of Hg.…”

“…As ROS have very short half-lives [Pryor, 1986] and cannot be directly measured in epidemiological studies, we measured total plasma antioxidant concentration and blood antioxidant enzyme activities to assess the effects of chronic occupational exposure to oxidants in humans. Recently, we found that erythrocyte catalase and Cu ϩϩ /Zn ϩϩ SOD activities could be considered markers of oxidative stress in workers exposed to mercury vapors [Perrin-Nadif et al, 1996b]. Although antioxidant enzymes are closely related to carcinogenesis [Sun, 1990], the relationship between occupational exposure to PAHs and oxidative stress has not been sufficiently investigated in healthy exposed workers.…”

Diclofenac Sodium, a Nonselective Nonsteroidal Anti-Inflammatory Drug Aggravates Doxorubicin-Induced Cardiomyopathy in Rats

“…36 Various endogenous adaptive responses with the endogenous antioxidant enzymes (CAT, GSH, and SOD) come into play to counteract the damage caused by ROS. 37,38 In pathologic conditions of altered redox balance, these enzymes are consumed to neutralize free radicals; therefore, measurement of the endogenous antioxidant enzymes have been performed to assess the amount of oxidative stress. The activity of the CAT was significantly raised, whereas the GSH and SOD was significantly reduced in cardiac tissue of the DIC alone and/or in combination with the DOX-treated animals compared with the control (P , 0.05 and P , 0.001) and the toxic control (P , 0.001) animals, respectively.…”