Superoxide dismutase: a review and a modified protocol for activities measurements in rat livers

Superoxide dismutase (SOD) enzymes are considered the first line of Defence against reactive oxygen species. Among the intracellular isoforms of SOD, Cu,ZnSOD is widely distributed, and the MnSOD is localised in the mitochondria. The SOD activities have been measured indirectly by inhibiting oxidation reactions. Most techniques assessing the hepatic SOD activity are adaptations of classical methods and differ significantly from each other. This work assessed the hepatic Cu,ZnSOD activity in the supernatants of two different centrifugations, using two isotonic medium and the pyrogallol method. In most studies conducted in rat liver, only the Cu,Zn or total SOD activities were assessed and sometimes the Cu,ZnSOD activity was calculated based on the inhibition by cyanide. But, as demonstrated here, this inhibition is not complete. Besides, the novelty of this work is that we presented a method for the evaluating the Cu,ZnSOD and MnSOD activities separately and from the same liver.