Measurement of urinary excretion of 5-hydroxymethyluracil in human by GC/NICI/MS:: Correlation with cigarette smoking, urinary TBARS and etheno DNA adduct

摘要: Abstract 5-Hydroxymethyluracil (5-HMU) is derived from radiation in addition to endogenous oxidative DNA damage and it one of the most abundant adducts. Human 5-HMU-DNA-glycosylase has been shown repair this lesion. Whether urinary levels 5-HMU a valid biomarker for vivo investigated. However, controversial results on its relation cigarette smoking were reported. To facilitate analysis epidemiological studies, highly sensitive specific assay based stable isotope dilution gas chromatography/negative ion chemical ionization/mass spectrometry was developed. The limit detection N1,N3-bis(pentafluorobenzyl)-HMU 10 fg (20 amol) (S/N = 4) injected column quantification urine 0.7 nM 5-HMU. Using as little 10 μL human samples, 21 healthy volunteers accurately quantified. No correlation observed between smoking. there statistically significant association thiobarbituric acid-reactive substances (r = 0.71, p = 0.0003). In addition, also correlated with 1,N6-ethenoadenine (r = 0.54, p = 0.01). These findings suggest that should be valuable assessing role repair.