Reactive Oxygen Species, Antioxidant Mechanisms, and Serum Cytokine Levels in Cancer Patients:
Impact of an Antioxidant Treatment
 (PubMed, Journal of Environmental Pathology, Toxicology and Oncology, 2003:22(1))

Researchers at the University of Cagliari in Italy studied 28 advanced stage cancer patients by dividing them into 5 groups and assigning one of 5 antioxidant treatments to each group. Their goal was to distinguish whether the oxidative stress levels found in the cancer patients resulted from the body producing excess oxidants or a defect in the body's ability to counteract oxidants. The researchers administered the antioxidants daily for 10 days, during which time they performed various tests, including monitoring blood levels of reactive oxygen species, a marker for free radicals. They also tested for glutathione peroxidase and superoxide dismutase, enzymes produced by the body to counteract reactive oxygen species. The investigators found that 4 of the antioxidants reduced reactive oxygen species levels and 2 of them (cysteine-containing compounds and amifostine) also increased glutathione peroxidase activity. These findings suggest that antioxidants have potential for treating cancer patients because they both reduce reactive oxygen species levels and boost glutathione peroxidase activity.