Radical-scavenging antioxidants in pre-eclampsia and eclampsia.

OBJECTIVE: Increased free-radical activity may be implicated in the pathogenesis of pre-eclampsia and knowledge of the response of the antioxidant systems is limited in pre-eclampsia and lacking in eclampsia. Accordingly, this study was initiated to assess total antioxidant status in pre-eclampsia and eclampsia. METHOD: Thirty-five patients with pre-eclampsia (20 mild and 15 severe), 10 patients with eclampsia and 20 normotensive women (controls) with singleton gestations in the third trimester participated in this study. Their freshly drawn blood was assayed for total antioxidant status colorimetrically using incubation mixture of ABTS, a peroxidase (metmyoglobin) and H2O2. In addition, serum fibronectin was determined by radial immunodiffusion. RESULT: Serum total antioxidant status levels in mild and severe pre-eclampsia and eclampsia were significantly lower than that of healthy pregnant women (controls). The mean percent decreases amounted to 22%, 40% and 59%, respectively, indicating the propensity of these patients to oxidative stress. CONCLUSION: These results demonstrate that radical-scavenging antioxidants are consumed by the increased free-radical activity in pre-eclampsia. The mechanisms by which free radicals are involved in endothelial dysfunction and renal injury are explained as evidenced by significant negative correlation of fibronectin and positive correlation of creatinine clearance with total antioxidants.

The cardiovascular safety of triphasic contraceptive steroids.

It was hypothesized that estrogen-induced cardioprotection is mediated by up-regulation and down-regulation of expression of nitric oxide (NO) and P-selectin, respectively. Published data on circulating levels of the vasodilator NO, atherogenic glycoprotein P-selectin, and lipoprotein-a [Lp(a)] in users of triphasic contraceptive steroids are lacking. A total of 30 healthy women (nonusers, controls) and 82 women using oral triphasic contraceptive steroids (ethinyl estradiol and levonorgestrel: Triovlar, Schering AG) for 18 to 24 cycles participated in this study. Fasting blood samples were obtained from users and nonusers for the determination of P-selectin and Lp(a) by enzyme immunoassay and NO by a colorimetric method. The serum Lp(a) levels in OC users were significantly higher than those of nonusers. On the other hand, the serum NO levels in OC users were significantly elevated when compared to nonusers. Plasma P-selectin was significantly lowered in OC users p < 0.005. These results demonstrate the beneficial effects of ethinyl estradiol in the triphasic contraceptive regimen. Ethinyl estradiol may afford a degree of anti-atherogenic-cardioprotective effect by up-regulation of the expression of the vasodilator NO and down-regulation of the expression of the atherogenic P-selectin. This may outweigh the cardiovascular risk of the increased atherogenic Lp(a). This study may explain the very low rate of mortality from venous thromboembolism in OC users, which compares favorably with the risks that many people accept in daily life.