کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2603487 1133822 2008 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Discriminative protection against hydroxyl and superoxide anion radicals by quercetin in human leucocytes in vitro
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم محیط زیست بهداشت، سم شناسی و جهش زایی
پیش نمایش صفحه اول مقاله
Discriminative protection against hydroxyl and superoxide anion radicals by quercetin in human leucocytes in vitro
چکیده انگلیسی

Antioxidants play a vital role in the cellular protection against oxidative damage. Quercetin is a well-investigated antioxidant and known to be able to protect against cellular oxidative DNA damage. In this study, we tried to relate the protection by quercetin pre-treatment against oxidative DNA damage in human leucocytes in vitro to the interaction of quercetin in solution with hydroxyl and superoxide anion radicals as measured by electron spin resonance (ESR) spectrometry, using DMPO as a spin trap. Further, scavenging capacity of quercetin-treated leucocytes in vitro was evaluated by ESR spectrometry. Quercetin appears capable of protecting human leucocytes against oxidative DNA damage caused by hydrogen peroxide in a dose-dependent manner. The protection of leucocytes against superoxides is ambiguous. Incubation concentrations of quercetin (1, 10, and 50 μM) reduced levels of superoxide-induced oxidative DNA damage, while at 100 μM the amount of damage was increased. These results are supported by ESR-findings on quercetin in solution, also showing a prooxidant effect at 100 μM. ESR spectroscopy showed rate constant values for the reaction kinetics of quercetin in lowering iron-dependent hydroxyl radical formation and NADH-dependent superoxide anion formation of respectively 3.2 × 1012 M−1 s−1 and 1.1 × 104 M−1 s−1. This shows that quercetin is a more potent inhibitor of hydroxyl radical formation than a scavenger of superoxide anions.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Toxicology in Vitro - Volume 22, Issue 2, March 2008, Pages 301–307
نویسندگان
, , , ,