Dexmedetomidine acts as an oxidative damage prophylactic in rats exposed to ionizing radiation

Abstract

Study objective To investigate the effects of dexmedetomidine on oxidative injury caused by ionizing radiation. Design Randomized controlled experimental study. Setting Department of radiation oncology and research laboratory of an academic hospital. Interventions Twenty-eight rats were randomized to 4 groups (n = 7 per group). Group S rats were administered physiologic serum; group SR rats were administered physiologic serum and 10 Gy external ionizing radiation. Groups D100 and D200 were administered 100 and 200 ?g/kg dexmedetomidine intraperitoneally, respectively, 45 minutes before ionizing radiation. Measurements Liver, kidney, lung, and thyroid tissue and serum levels of antioxidant enzymes (glutathione peroxidase [GPX], superoxide dismutase, and catalase) and oxidative metabolites (advanced oxidation protein products, malondialdehyde, and nitrate/nitrite, and serum ischemia-modified albumin) were measured 6 hours postprocedure. Main results In group SR, IR decreased antioxidant enzyme levels and increased oxidative metabolite levels (P < .05). In plasma, antioxidant enzyme levels were higher and oxidative metabolite levels were lower in groups D100 and D200 than in group SR (P < .01). In tissues, hepatic and lung GPX levels were higher in groups D100 and D200 than in group SR (P < .001). Renal and thyroid GPX levels were higher in D200 than in group SR (P < .01). Thyroid superoxide dismutase levels were higher in groups D100 and D200 than in group SR (P < .01). Renal, lung, and thyroid catalase levels were higher in group D200 than in group SR (P < .01). Hepatic, renal, and lung advanced oxidation protein products and malondialdehyde levels were lower in groups D100 and D200 than in group SR (P < .01). Hepatic, renal, and lung nitrate/nitrite levels were lower in group D200 than in group SR (P < .05). Conclusions Dexmedetomidine preserves the antioxidant enzyme levels and reduces toxic oxidant metabolites. Therefore, it can provide protection from oxidative injury caused by ionizing radiation. © 2016 Elsevier Inc.