PP027. Alterations in maternal antioxidant micronutrient concentrations in women prior to developing pre-eclampsia

Introduction: Changes in plasma antioxidant trace elements during pregnancy are closely related to mortality and morbidity in the newborn. Deficiencies of specific micronutrient antioxidant activities, associated with copper, selenium, zinc and manganese have previously been associated with pre-eclampsia (PE) at term. The purpose of the present study was to investigate these maternal plasma micronutrient concentrations with associated enzyme activities, specifically the copper-related caeruloplasmin, in a subcohort of the international SCreening fOr Pregnancy Endpoints (SCOPE) study, in early pregnancy, prior to disease onset.

Methods: Pre-disease plasma samples (14-16+6 weeks') collected from women who subsequently developed PE (n=245) and age- and BMI-matched uncomplicated normotensive controls (NC; n=471) were used following written informed consent. Micronutrient concentrations were measured by inductively-coupled mass spectrometry and caeruloplasmin activity by colorimetric activity assay.

Results: Plasma copper concentrations at 15 weeks' gestation were significantly elevated in women who subsequently developed PE; no differences were seen for all other micronutrients (Table). No differences were seen in caeruloplasmin activity between the two groups. However, a positive association between copper concentration and caeruloplasmin activity was observed (r=0.305; R2=0.093; P<0.0001).

Conclusion: Copper has a dual function in pregnancy, while it may be beneficial as a cofactor for numerous antioxidant enzymes, it also a redox-active transition metal, which catalyses the formation of free radicals and increased levels may contribute to oxidative stress status in PE. These data indicate that although women with PE show significantly higher copper, the caeruloplasmin activity is not significantly higher. It seems that during PE, the activity does not increase proportionally with the levels of copper and may indicate a dysfunction of the antioxidant enzyme. Work is underway to characterise copper-dependent antioxidant superoxide dismutase activity and markers of oxidative stress in these women.

Funding: British Heart Foundation (Charity No. 225971).