Inhibition of photohemolysis induced by m-chloroperbenzoic acid by metal complexes with SOD-mimetic activity

Red blood cells (RBCs) are probably the most common target through the damaging action of reactive oxygen species on the cells. The photohemolysis activity of m-chloroperbenzoic acid (CPBA) was concentration- and exposure time-dependent. Twenty minutes photo exposure time and 200 μm of CPBA concentration were optimum to study the effect of generated superoxide (O_{2-) and hydroxyl (&bull•OH) radicals on RBCs. RBCs lysis photosensitized by CPBA was investigated in the presence of (VL2O)(VL2H2O)]Cl6, MnL2O]2Cl42H2O, FeL2Cl2]Cl H2O, CoL2Cl2]4H2O or ZnL2Cl2]H2O respectively, where L is 2-methylaminopyridine, with SOD-mimetic activities with the aim of ascertaining their protective activity towards the photo induced cell damage. The decrease of photolytic activity caused by these complexes was concentration-dependent and the maximum percentage of protective activity was 75, 70, 68, 57 or 24% for (VL2O)(VL2H2O)]Cl6, MnL2O]2Cl4 2H2O, FeL2Cl2]Cl H2O, CoL2Cl2]4H2O or ZnL2Cl2]H2O complex respectively, against the cell irradiated without addition of metal complexes. The comparison between the decrease of photolytic activity caused by these complexes and their SOD-mimetic activity of these metal complexes showed an appreciable correlation.}