Increased oxidative DNA damage, as assessed by urinary 8-hydroxy-2'-deoxyguanosine concentrations, and serum redox status in persons exposed to mercury.
BACKGROUND
Mercury is a ubiquitous and highly toxic environmental pollutant. In this study, we evaluated the relationship between mercury exposure and oxidative stress, serum and urinary mercury concentrations, oxidative DNA damage, and serum redox status in chronically mercury-exposed persons compared with healthy controls.


METHODS
We measured urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG), which we used as a biomarker of oxidative DNA damage in the mercury-exposed persons, by HPLC with electrochemical detection (ECD). We evaluated antioxidant status by measuring the activities of superoxide dismutase and glutathione peroxidase and the concentrations of total reduced glutathione and protein-bound thiols in serum.


RESULTS
The significant increase in 8-OHdG concentrations in urine indicated that mercury-induced oxidative damage to DNA occurred in vivo. Differences in body mercury burden and antioxidant enzyme activities were statistically significant between the mercury-exposed persons and controls. Serum and urinary mercury concentrations in the mercury-exposed persons were more than 40-fold higher than in controls.


CONCLUSIONS
Mercury exposure can induce oxidative DNA damage, whereas the antioxidative repair systems can be expected to minimize DNA lesions caused by mercury. Measurement of urinary 8-OHdG could be useful for evaluating in vivo oxidative DNA damage in mercury-exposed populations.
Chen
Chunying
C
Key Laboratory of Nuclear Analytical Techniques and Laboratory for Nanoscale Materials and Related Bio-Environmental Sciences, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, Peoples Republic of China.
Qu
Liya
L
Li
Bai
B
Xing
Li
L
Jia
Guang
G
Wang
Tiancheng
T
Gao
Yuxi
Y
Zhang
Peiqun
P
Li
Mei
M
Chen
Wei
W
Chai
Zhifang
Z
D000080242:8-Hydroxy-2'-Deoxyguanosine; D000328:Adult; D000368:Aged; D000975:Antioxidants / Q000032:analysis*; D001798:Blood Proteins / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D004249:DNA Damage; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000652:urine*; D004785:Environmental Pollutants / Q000097:blood / Q000633:toxicity* / Q000652:urine; D005978:Glutathione / Q000097:blood; D005979:Glutathione Peroxidase / Q000097:blood; D006801:Humans; D017669:Mercury Compounds / Q000097:blood / Q000633:toxicity* / Q000652:urine; D008875:Middle Aged; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D011485:Protein Binding; D044967:Serum; D013438:Sulfhydryl Compounds / Q000097:blood; D013482:Superoxide Dismutase / Q000097:blood
D000975:Antioxidants; D001798:Blood Proteins; D004785:Environmental Pollutants; D017669:Mercury Compounds; D013438:Sulfhydryl Compounds; D000080242:8-Hydroxy-2'-Deoxyguanosine; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D003849:Deoxyguanosine; D005978:Glutathione