Protective Role of Astaxanthin on Radiation-Related Intestinal Toxicity in Rats

Abstract

OBJECTIVE Radiation (RT)-induced intestinal toxicity is a common complication of abdominal or pelvic radiation therapy. Although the underlying pathological features are partially clarified, the appropriate treatment approach is not yet clear. Herein, we sought the protective role of astaxanthin (ATX), which is a natural antioxidant, on the RT-induced toxicity in the rat intestine. METHODS Male Wistar rats that are 10-12 weeks old and weighing 250-350 g were divided into four groups: control, RT alone, RT+ATX, and ATX alone as Groups 1, 2, 3, and 4, respectively. RT was given to the abdomen as one fraction of 8 Gy, and ATX was given as 4 mg/kg for 7 days before RT. Intestinal tissues were taken 24 h after the last ATX injection and radiation for histopathologic, immunohistochemical examination, and oxidative stress measurement. RESULTS Oxidative stress index and oxidant status decreased with ATX administration in the radiation group where an increase was reported in total antioxidant status. ATX treatment decreased the pathological expressions observed in the proprial and epithelial cells of the intestinal villi in the RT group. Similarly, RT exposure increased TNF-α expression while ATX treatment decreased the immunoreaction. CONCLUSION Our results demonstrate that radiation induces apoptosis and histopathologic intestinal mucosal changes which leads to an increase in oxidative stress. ATX significantly ameliorates radiation-induced reactions with its superior antioxidant properties and additional anti-inflammatory and antiapoptotic activities.