Physiological variations of isoprostanes: a step forward?

Abstract

To the Editor: Ide et al1 recently reported that 15-F2t-IsoP urinary levels were higher in healthy young men compared with healthy premenopausal women, showing that lipid peroxidation is increased in the former group. Isoprostanes appear to be specific and sensitive biomarkers of lipid peroxidation2 and are widely used in clinical trials. Unlike the 5-series and the 15-F2t-IsoP metabolites, our knowledge of the physiological variations of 15-F2t-IsoP is increasing, essential criteria before assessing this biomarker in pathological states. The study by Ide et al provides important but incomplete information concerning the physiological variations of 15-F2t-IsoP in humans. This study was meticulously performed, using a validated assay.3 The numerous exclusion criteria (smoking, hypertension, dyslipidemia, diabetes, alcoholism, medication including vitamins and oral contraceptives) give weight to the validity of the results, because few biases are likely to have been introduced. Furthermore, four potential limitations of the study that the authors outline in the discussion can reasonably be ruled out: the confounding effects of exercise or of …