Green Tea Extract Attenuates Oxidative Stress and Prolongs Red Blood Cell Survival in Iron-Overloaded β-Thalassemic Mice

Green tea extract (GTE) contains catechin polyphenols with potent antioxidant and iron-chelating activities. This study investigated whether GTE could attenuate oxidative stress and improve red blood cell (RBC) survival in iron-overloaded β-thalassemic mice. Catechin composition and antioxidant activity of GTE and black tea extract (BTE) were evaluated using HPLC-photodiode array detection and ABTS radical scavenging assays. Anti-hemolytic effects were examined in RBC from healthy subjects and transfusion-dependent β-thalassemia patients. In vivo studies were performed using male C57BL/6J wild-type (WT) and heterozygous β-globin knockout (BKO) mice fed a ferrocene-enriched diet to induce iron overload. Mice subsequently received oral GTE (300 mg/kg/day) or deferiprone (DFP, 50 mg/kg/day) for 12 weeks. GTE contained markedly higher levels of catechin derivatives, particularly epigallocatechin-3-gallate, and exhibited stronger antioxidant activity than BTE. GTE significantly reduced RBC hemolysis, reactive oxygen species, malondialdehyde, and plasma non-transferrin-bound iron levels while restoring glutathione concentrations and prolonging RBC survival in iron-overloaded mice. The protective effects of GTE were comparable to DFP treatment. These findings suggest that GTE may serve as a promising natural adjunctive strategy for reducing oxidative injuries in β-thalassemia and iron-overload disorders.