Elm bark extract improves immunomodulation and ameliorates oxidative stress in irradiated mice

Abstract

Background Radiation therapy can result in side effects such as cellular and tissue inflammation and organ damage. Previously, elm bark (EB) extract has been reported to exert antioxidant and anti-inflammatory effects. In this study, we investigated whether EB administration could improve immunocompetence and ameliorate radiation-induced intestinal damage in irradiated mice. Methods After exposure to radiation of 15 Gy, mice were orally administered with EB extract (0 mg/kg, 50 mg/kg, and 500 mg/kg body weight) every other day for 2 weeks, and there was a 2-week washout period. The proliferation of splenocytes and cytokine production of macrophage were measured as indices of immune activity, and histological grade and antioxidant levels in radiation-induced intestinal injury were measured. Results Radiation exposure reduced the T-cell proliferation in splenocytes and the levels of interleukin-1β and interleukin-6 from macrophage at Week 2. The supplement of EB extract at low concentration (50 mg/kg body weight; EB-50) tended to enhance T-and B-cell proliferation in irradiated mice. The histological grades of the small intestine were induced by radiation exposure, whereas histological grade of the EB-50 group was lower than that of the irradiated control at Week 4. The EB-50 treatment reduced the level of glutathione at Day 5 and Week 2 and reduced myeloperoxidase activity at Week 4, suggesting that EB-50 may counteract the intestinal inflammation caused by radiation exposure. Conclusion Our results indicate that EB extract (50 mg/kg body weight) protects against radiation damage, at least in part, by improving immunomodulation and ameliorating oxidative stress in irradiated mice. © 2017 Korea Food Research Institute