|
KMID : 1134820060350080979
|
|
Journal of the Korean Society of Food Science and Nutrition
2006 Volume.35 No. 8 p.979 ~ p.984
|
|
|
Effect of Iron Excess-induced Oxidative Stress on Platelet Aggregation
|
|
Seo Geun-Young
Park Hyo-Jin
Jang Sung-Geun
Park Young-Hyun
|
|
|
Abstract
|
|
|
|
Although iron is essential for many physiological processes, excess iron can lead to tissue damage by promoting the generation of reactive oxygen species (ROS). There is increasing evidence that ROS might play an important role in the pathogenesis of cardiovascular disease. However, the effects of iron excess on platelet function and the thrombotic response to vascular injury are not well understood. We examined the effects of iron excess?induced oxidative stress and the antioxidants on platelet aggregation. Oxidative stress was accessed by either free iron (Fe?²) or hydrogen peroxide (H₂O₂), as well as their combination on washed rabbit platelets (WPs) in vitro. When WPs were stimulated with either Fe?² alone or a subthreshold concentration of collagen, which gave an aggregatory curve with a little effect, and a dose dependent increase in platelet aggregation was observed by increasing concentrations of Fe?² with H₂O₂. This aggregation was associated with the iron-catalyzed formation of hydroxyl radicals from H₂O₂, and were inhibited by NAD/NADP (proton acceptor), catalase (H₂O₂ scavenger), tiron (iron chelator), mannitol (hydroxyl radical scavenger), and indomethacin (cyclooxygenase inhibitor), but not by NADH/NADPH (proton donor), superoxide mutase, and aspirin. However, NADH/NADPH, an essential cofactor for the antioxidant capacity by the supply of reducing potentials, showed the effect of an enhanced radical formation, suggesting a role for NADH/NADPH-dependent oxidase. These results suggest that iron (Fe?²) can directly interact with washed rabbit platelets and this aggregation be mediated by OH? formation as in the Fenton reaction, inhibited by radical scavengers.
|
|
|
KEYWORD
|
|
|
iron, free radical, oxidative stress, platelet aggregation, antioxidants
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|