The steady-state levels of oxidative DNA damage and of lipid peroxidation (F-2-isoprostanes) are not correlated in healthy human subjects

Oxidative damage to DNA in human tissues can be determined by measuring mul tiple products of oxidative damage to the purine and pyrimidine bases using gas chromatography-mass spectrometry (GC-MS). Oxidative damage to lipids ( lipid peroxidation) can be quantitated by the mass spectrometry-based deter mination of F-2-isoprostanes, specific end-products of the peroxidation of arachidonic acid residues in lipids. For both DNA base damage products and 8-epi prostaglandin F-2 alpha (PGF(2 alpha)), there is a wide variation in levels between different healthy human subjects. We measured multiple produ cts of oxidative damage to DNA bases in white cells, and 8-epi PGF(2 alpha) in plasma, from blood samples obtained from healthy human subjects in the UK and in Portugal. No correlation of 8-epi PGF(2 alpha) levels with levels of any modified DNA base (including 8-hydroxyguanine) was observed. We con clude that no single parameter can be measured as an index of "oxidative st ress" or "oxidative damage" in vivo.