Urinary excretion of 8-hydroxy-2'-deoxyguanosine measured by high-performance liquid chromatography with electrochemical detection.
There is good evidence that oxidative DNA damage permanently occurs in living cells. The oxidative DNA damage product 8-hydroxy-2'-deoxyguanosine (8-OHdG) is one of the predominant forms of radical-induced lesions to DNA, and has therefore been widely used as a biomarker for oxidative stress, either in cellular DNA or as DNA repair product in urine. In this paper we describe the use of a high-performance liquid chromatographic procedure with electrochemical detection for the measurement of urinary 8-OHdG. Our study has addressed the questions (i) of baseline urinary levels of 8-OHdG in spot urine and 24-h urine, (ii) of inter- and intra-individual variation of this biomarker, and (iii) of confounding factors for the excretion of 8-OHdG. No significant difference between the mean group levels of 8-OHdG/creatinine in spot urine (2.03+/-1.21 micromol/mol, n=148) and in 24-h urine (1.86+/-1.09 micromol/mol, n=67) was observed. However, when only 24-h urine was used for analysis, 8-OHdG was found to be statistically significantly higher in smokers. By multiple linear regression analysis, urinary creatinine was identified as the only predictor of 8-OHdG/24 h (r(p)=0.33, P=0.007). High intra-individual coefficients of variation of 8-OHdG/24 h were observed in two healthy subjects over a period of 10 consecutive days (37 and 57%, respectively), indicating that the intra-individual fluctuation of urinary 8-OHdG has so far been underestimated. Therefore, we suggest that single values of 8-OHdG should be considered with caution, in particular in small study groups and when spot urine is used.
Pilger
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Department of Occupational Medicine, Vienna General Hospital, University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria. alex.pilger@akh-wien.ac.at
Ivancsits
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Germadnik
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Rüdiger
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D000080242:8-Hydroxy-2'-Deoxyguanosine; D000328:Adult; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000652:urine*; D004563:Electrochemistry; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress
D000080242:8-Hydroxy-2'-Deoxyguanosine; D003849:Deoxyguanosine