Urinary 6-sulfatoxymelatonin level in age-related macular degeneration patients

[摘要] Purpose: Melatonin is a potentantioxidant and free radical scavenger. It has been reported that serummelatonin level is relevant to certain aging diseases. The purpose ofthis study was to investigate melatonin levels in age-related maculardegeneration (AMD) patients by measurement of 6-sulfatoxymelatoninlevels (aMT6s), the major metabolite of melatonin in urine, and compareit with a group of age- and gender-matched controls. Methods: The first urine of the morningwas collected from 43 AMD patients and 12 controls who did not haveAMD. The level of aMT6s in specimens was measured by a commercial6-sulfatoxymelatonin ELISA kit. The assay was performed by researchers,who were masked to the clinical information. To adjust for variation inthe diluteness of urine, urinary creatinine level was measured andaMT6s levels were expressed as aMT6s/creatinine. Results: The level of urinaryaMT6s/creatinine (mean±SD) in AMD (6.24±3.45 ng aMT6s/mg creatinine)was significantly lower than that of the controls (10.40±4.51,p=0.0128). After adjustment for various factors (age, smoking, cancer,and coronary heart disease) that may influence the aMT6s level, theodds-ratio of urinary aMT6s comparing AMD patients to controls was 0.65(95% confidence interval=0.48–0.88, p=0.0036), indicating that urinaryaMT6s level in AMD patients was lower than in controls even aftermultivariate adjustment. Conclusions: Urinary aMT6s level in AMDpatients was 40% lower than in age- and gender-matched controls. Thisdifference between AMD patients and controls is present afteradjustment for the factors of age, smoking, and histories of cancer andcoronary heart disease. The significance of this result and the role ofmelatonin in the occurrence of AMD require further investigation.

[学科分类] 生物化学/生物物理