Radioprotective effects of nitroxide compound NHCOCH3-TEMPO in BALB/c mice

Abstract

Objective To investigate the protective effects of nitroxide compound NHCOCH3-TEMPO against γ-ray irradiation-induced injury in male BALB/c mice. Methods 120 BALB/c male mice were randomly divided into two super group, each super group then were randomly divided into 6 groups: control group, normal saline(NS)+ γ group, low-dose TEMPO+ γ group, middle-dose TEMPO+ γ group, high-dose TEMPO+ γ group and the positive control (WR-2721)+ γ group. BALB/c mice were intraperitoneally injected with nitroxide compound at 0.5 h before whole body 60Co γ-ray irradiation. The drug dosages were as follows: WR-2721 group 200 mg/kg, low-dose TEMPO group 100 mg/kg, middle-dose TEMPO group 200 mg/kg, high-dose TEMPO group 400 mg/kg. The first super group of the mice was given 7 Gy γ-ray whole-body irradiation, and then 30 d survival rate was observed. The second super group of the mice was given 4 Gy γ-ray whole-body irradiation. The number of nucleated cells and the content of DNA in bone marrow, as well as the blood routine were detected. Results At 8th and 15th day after 4 Gy γ-ray irradiation, the number of bone marrow nucleated cells, the content of DNA significantly increased in TEMPO+ γ-ray groups compared with NS+ γ-ray group(t=2.53-6.13, P<0.05). The number of white blood cells significantly increased in middle dose TEMPO+ γ-ray groups compared with NS+ γ-ray group(t=4.34, P<0.05), while there was no significant difference in the number of red blood cells between the TEMPO+ γ-ray group and the NS+ γ-ray group. After 7 Gy γ-ray irradiation, the survival rate of mice on the 30th day significantly increased in low-dose TEMPO+ γ-ray group compared with NS+ γ-ray group(χ2=5.934, P<0.05). Conclusions The nitroxide compound NHCOCH3-TEMPO could provide radio protective effects in BALB/c mice. Key words: Nitroxide compound; BALB/c mice; γ-rays; Radiation protection