Excessive iron is toxic to cells and organelles, where it can generate harmful reactive oxygen species (ROS) resulting in oxidative tissue damage. Liver is the major organ for iron storage and redox active iron in this tissue can cause fibrosis and cirrhosis in β-thalassemia patients. Desferrioxamine (DFO), deferiprone (DFP) and deferasirox (DFX) are clinically approved iron chelators used for the treatment of patients with iron overload, but none of these chelators are completely free of side effects. In this study we report the properties of a new iron chelator 1-(N-acetyl-6-aminohexyl)-3-hydroxypyridin-4-one (CM1). The labile iron pool (LIP) content was measured by using a calcein fluorescence technique and the lipidperoxidation products were quantified using the thiobarbituric acid reactive substances (TBARS) method. The cytotoxicity of CM1 was also examined with the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. CM1 was demonstrated to reduce iron-induced redox damage and to decrease the levels of the intracellular iron pool in hepatocytes. CM1 is a potentially useful iron-chelating agent which has potential to ameliorate liver iron overload and ROS-induced lipid peroxidation. CM1 is currently under investigation for oral efficacy.
KeywordsIron3-Hydroxypyridin-4-OneLabile Iron PoolLipid PeroxidationHepatocyte
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