Anti-apoptotic, anti-inflammatory, and immunomodulatory activities of 3,3'-diselenodipropionic acid in mice exposed to whole body γ-radiation.

The present study was designed to evaluate the possible protective effects of 3,3'-diselenodipropionic acid (DSePA), a potent radioprotector, against oxidative organ damage induced by whole body γ-irradiation and explore its mechanistic effects. The mice were subjected to whole body γ-irradiation at 5 Gy for the detection of oxidative stress, apoptosis, and proliferation in the intestinal (jejunum) tissue and at 7 Gy for the examination of intestinal inflammation and immune imbalance. Groups of mice received intraperitoneal injections of DSePA (2 mg/kg/day) or vehicle (phosphate-buffered saline) for 5 consecutive days prior to irradiation. The whole body γ-irradiation of mice led to the induction of oxidative stress and apoptosis in the intestinal tissue, and pretreatment with DSePA significantly reduced both these parameters. It was also found to abrogate the radiation-induced intestinal inflammatory response and augment the proliferation of intestinal cells. Additionally, irradiation-induced polarization of Th1/Th2 immune balance toward the Th2-dominant direction and pretreatment with DSePA ameliorated this shift, which may be beneficial for the recovery from radiation injury. In conclusion, pretreatment with DSePA prevented radiation-induced oxidative damage in small intestine and the underlying mechanisms responsible for this could be attributed to inhibition of oxidative stress, apoptosis, and inflammation.