Determination of Urinary 8-Hydroxydeoxyguanosine by Coupled-Column High-Performance Liquid Chromatography with Electrochemical Detection: A Noninvasive Assay for in Vivo Oxidative DNA Damage in Humans

Oxidative damage to DNA has been suggested to contribute to a number of diseases including cancer and chronic inflammation. In order to study the relationship between oxidative damage to DNA and diseases, it is desirable to develop techniques that can be used for the analysis of DNA damage products in individuals. The present article describes a sensitive analytical method for determination of the oxidative DNA adduct, 8-hydroxydeoxyguanosine (80HdG) in human urine, based on coupled-column high-performance liquid chromatography with electrochemical detection. The method measures down to 2 nmol 80HdG/L urine, which is well below the levels of 80HdG in normal human urine (5-15 nmol/L). It is shown that smokers excrete slightly more 80HdG in their urine than nonsmokers and that patients undergoing radiotherapy or chemotherapy for different malignant diseases excrete significantly more than healthy individuals. The potential use of the method for detecting increased urinary 80HdG excretion and conditions associated with increased oxidative DNA damage in humans is discussed. It is suggested that the assay could be used to detect damage resulting from the exposure of an individual to foreign compounds that stimulate production of reactive oxygen metabolites, and that it could be used to investigate conditions with high rates of DNA damage and repair. Furthermore, the assay may be used to compare 80HdG excretion before and after various types of antioxygen treatment and so help to identify treatments that protect human beings from oxidative DNA damage.