Organic derivatives of mercury and tin as promoters of membrane lipid peroxidation.

The toxicity mechanisms of mercury and tin organic derivatives are still under debate. Generally the presence of organic moieties in their molecules makes these compounds lipophilic and membrane active species. The recent results suggest that Hg and Sn compounds deplete HS-groups in proteins, glutathione and glutathione-dependent enzymatic systems; this process also results in the production of reactive oxygen species (ROS), the enhancement of membrane lipids peroxidation and damage of the antioxidative defence system. The goal of this review is to present recent results in the studies oriented towards the role of organomercury and organotin compounds in the xenobiotic-mediated enhancement of radical production and hence in the promotion of cell damage as a result of enhanced lipids peroxidation. Moreover the conception of the carbon to metal bond cleavage that leads to the generation of reactive organic radicals is discussed as one of the mechanisms of mercury and tin organic derivatives toxicity. The possible use of natural and synthetic antioxidants as detoxification agents is described. The data collected recently and presented here are fundamentally important to recognizing the difference between the role of metal center and of organic fragments in the biochemical behavior of organomercury and organotin compounds in their interaction with primary biological targets when entering a living organism.