Oral antioxidants for radioprotection during medical imaging examinations

The oncogenic effect of ionizing radiation (IR) is clearly established and occurs in response to DNA damage. Many diagnostic imaging exams make use of IR and the oncogenic risk of IR-based imaging has been calculated. We hypothesized that the DNA damage sustained from IR exposure during medical imaging exams could be reduced by pre-medicating patients with antioxidants. First, we tested and validated a method for measuring DNA double-strand breaks (DSBs) in peripheral blood mononuclear cells (PBMCs) exposed to low doses of ionizing radiation. Afterwards, we conducted a pilot clinical study in which we administered oral antioxidants to patients undergoing bone scans, prior to radiotracer injection. We showed that oral antioxidant pre-medication reduced the number of DSBs in PBMCs induced by radiotracer injection. Our study shows proof-of-principle for this simple and inexpensive approach to radioprotection in the clinical setting. (author)