Influence exerted by redox-active metals on oxidative stress evidence in an experiment

Our research goal was to study influence exerted by Fe2+ and Cr6+ cations on oxidative stress signs during an experiment on Wistar rats. We detected that when these metals were introduced into animals it caused free radical oxidation activation which became apparent through changes in chemiluminescense intensity in blood serum, in increased malonic dialdehyde and diene conjugants concentrations in blood serum and tissues (liver and pancreas), and in depression of antioxidant enzymes of superoxide dismutase and catalase erythrocytes. We showed that Fe2+ introduction with drinking water in a dose equal to maximum permissible concentration (MPC) could cause moderate activation of free radical oxidation as iron was a key element in active particles generation in biological media, including superoxide-anion-radical and most reactive hydroxyl radical. As we studied possible influence exerted by another redox-active metal, namely Cr6+, in concentration equal to 1 MPC we also detected enhanced free radical processes in blood serum which became more intense as exposure duration grew. Luminescence sum representing total antioxidant blood serum activity was almost 2.5 times higher as per two experimental periods when Cr6+ was introduced in comparison with intact animals. Processes activation under chromium cations effects is determined by its direct influence on free-radical mechanisms. Cr6+ ions recover to Cr3+in biological media; one-electron recovery process with intermediates forming at intermediate oxidation levels involves occurrence of active oxygen forms; it results in free radical processes enhancement.