304 - Changes in antioxidant components in midlife women. Is it age or menopause?

Abstract

Background The estrogen decline associated with menopausal transition is believed to be the ‘spark’ that triggers oxidative stress (OS), but it is difficult determinate if OS is due to the menopause changes or aging. Objective To determine OS antioxidant markers in midlife and aged women, and their association with the menopausal state. Methods We carried out a cross-sectional study with 558 women (40-69 yrs) from Mexico City. We measured total plasma antioxidant status (TAS), and erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GPx) with Randox kits; also, we measured serum uric acid level with a Cobas analyzer. We asked the women to the date of last menstruation and then we stratify them according to the Stages of Reproductive Aging Workshop (STRAW) criteria to compare OS markers as premenopausal (PRE), early postmenopausal (POS) and late-POS women. Results The SOD activity statistically decreases after menopause (1.25±0.16, 1.21±0.15 and 1.16±0.09 U/g Hb; PRE, early-POS and late-POS, respectively). GPx activity and TAS decrease, and uric acid level increase in the late-POS group. A negative correlation between years after menopause and GPx activity (r=–0.245, p Conclusion Our findings suggest that SOD activity diminish in early-POS and the other antioxidants decrease with chronological aging. Uric acid level increase with the age in women.