Epigallocatechin-3-gallate and Epicatechin-3-gallate from Green Tea
Decrease Plasma Non-Transferrin Bound Iron and Erythrocyte Oxidative
Authors: Thephinlap, C.1; Ounjaijean, S.1; Khansuwan, U.1; Fucharoen,
S.1; Porter, J. B.1; Srichairatanakool, S.1
Source: Medicinal Chemistry, Volume 3, Number 3, May 2007, pp.
289-296(8)
Publisher: Bentham Science
Abstract:
β-Thalassemia patients suffer from secondary iron overload caused by
increased iron absorption and multiple blood transfusions. Excessive
iron catalyzes free-radical formation, causing oxidative tissue
damage. Non-transferrin bound iron (NTBI) detected in thalassemic
plasma is highly toxic and chelatable. Desferrioxamine and deferiprone
are used to treat the iron overload, but many side effects are found.
Epigallocatechin gallate (EGCG) and epicatechin gallate (ECG) in green
tea (GT) show strong antioxidant properties. We separated the EGCG and
ECG from GT extract using an HPLC, and examined their iron-binding and
free-radical scavenging activities. They bound Fe3+ rapidly to form a
complex with a predominant absorption at 560 nm. EGCG and ECG bound
chemical Fe3+ and chelated the NTBI in a time- and dose dependent
manner. They also decreased oxidative stress in iron-treated
erythrocytes. In conclusion, EGCG and ECG could be natural iron
chelators that efficiently decrease the levels of NTBI and free
radicals in iron overload.
Keywords: Epigallocatechin-3-gallate; epicatechin-3-gallate; green
tea; iron overload; non-transferrin bound iron; oxidative stress
Document Type: Research article
DOI: 10.2174/157340607780620608
Affiliations: 1: Department of Biochemistry,Faculty of Medicine,
Chiang Mai University, Chiang Mai 50200, Thailand.