RESUMO
Assessment of the presence and severity of alcohol hangovers relies on the subjective method of self-report. Therefore, there is a need of adequate biomarkers that (1) correlate significantly with hangover severity, and (2) correspond to the level of hangover-related performance impairment objectively. In this naturalistic study, n = 35 social drinkers participated. Urine samples were obtained the morning after alcohol consumption and after an alcohol-free control day. Concentrations of 5-hydroxytryptophol (5-HTOL), 5-hydroxyindoleacetic acid (5-HIAA) and the 5-HTOL/5-HIAA ratio were determined. The results confirm previous findings that 5-HTOL and the 5HTOL/5-HIAA ratio are useful biomarkers of recent alcohol consumption. Significant correlations were found with the amount of alcohol consumed, total drink time, and estimated BAC. However, urine concentrations of 5-HTOL and 5-HIAA (and their ratio 5HTOL/5-HIAA) did not significantly correlate with hangover severity. In conclusion, urine 5-HTOL, 5-HIAA, and the 5HTOL/5-HIAA ratio cannot be considered to be suitable biomarkers of alcohol hangover.
RESUMO
Cytochrome P450 1A2 (CYP1A2) plays an important role in drug metabolism. Caffeine (CAF) is converted into paraxanthine (PX) by this enzyme and is used as a xenobiotic substrate to determine the CYP1A2 phenotype in humans. A method for the quantification of CAF and PX in saliva was developed using liquid-liquid extraction with ethyl acetate and analysis with ultra-high-performance liquid chromatography. Peaks from CAF, PX and internal standard were resolved within 6min. The method was validated from 0.05 to 5µgmL(-1) CAF and 0.025-2.5µgmL(-1) PX. Inter- and intra-day accuracies ranged from 91.2 to 107.2% with precisions <13.5%. The limits of detection were 0.16 and 0.63 ngmL(-1) for PX and CAF, respectively. PX/CAF concentration ratios from volunteers were 0.26-1.09 with mean ratios of 0.78±0.26 and 0.38±0.10 for regular and light/non-coffee drinkers, respectively.
