Author(s): Takahiro Kataoka, Yuji Takata, Reo Etani, Yuichi Nishiyama, Atsushi Kawabe, Katsumi Hanamoto, Takehito Taguchi and Kiyonori Yamaoka
Low-dose irradiation activates antioxidative functions and inhibits oxidative damage. Although a wide range of health products have been developed using the activation of biological functions by low-dose irradiation, their effectiveness has not yet been confirmed. The purpose of this study was to determine whether cream containing ultralow volume radionuclides (UVR) protects against carrageenan-induced inflammatory paw edema in mice. Cream containing ultralow volume radionuclides (UVR-cream) or sham cream was applied to the right hind paw of mice and 50 μL of carrageenan was subsequently injected to the right hind paw. Results showed that carrageenan administration induced paw edema; however, application of UVR-cream significantly decreased paw volume at 4 hours. Application of UVR-cream produced slight improvement in carrageenan-induced paw edema compared with sham cream. However, no significant changes were observed in paw edema between sham cream and UVR-cream. Carrageenan administration significantly decreased catalase activity and total glutathione content in paw. No significant changes were observed in the catalase activity or t-GSH content in paw among carrageenan-only, sham cream, and UVR-cream. In conclusion, the effects of UVR-cream differed from the beneficial effects induced by lowdose irradiation, since application of the cream did not activate antioxidative functions.