The cytotoxic mechanisms of interest include, but are not limited to, oxygen activation and toxicity. Oxygen toxicity involves the generation of chemical species such as superoxide anion radical, singlet oxygen, hydrogen peroxide and hydroxyl radical. Aerobic organisms have engineered defenses against the deleterious effects of these species. Under conditions of persistent production, however, the normal body defenses may be overwhelmed causing a metabolic state called oxidative stress. My interests in the toxicity of xenobiotics and oxygen radicals include the beneficial effects of such defenses as the antioxidant vitamins, enzymes, and glutathione.
Recent work focuses on the effects of xenobiotics on mitochondrial function.
Since mitochondria are an important source of oxygen radical species , we are also characterizing the conditions under which hydroxyl radical is formed in this organelle. Vissers, MC and Thomas, C. Hypochlorous acid disrupts the adhesive properties of subendothelial matrix. Oxygen dependence of hypericin-induced phototoxicity to EMT6 mouse mammary carcinoma cells. Photoactivation of hypericin generates singlet oxygen in mitochondria and inhibits succinoxidase.