葛根黄酮的辐射防护及其机制的研究

Study on radiation protection of Pueraria Flavonid and its molecular mechanism

目的研究葛根黄酮对受照射小鼠的辐射防护作用及其作用机制。方法采用60Coγ射线照射小鼠模型,观察8Gy照射小鼠30d存活和死亡动物存活时间。在低剂量照射模型观察用药后外周血指标和脏器系数变化,用原位末端标记法观察受照射小鼠脾细胞凋亡,流式细胞仪检测脾细胞凋亡率,同时检测血清中抗氧化酶和脂质过氧化物水平。结果照前给予葛根黄酮能明显提高受照射小鼠的存活率。葛根黄酮能明显促进受低剂量(5Gy)照射后小鼠的外周血白细胞恢复,提高受照小鼠的胸腺和脾脏指数,抑制受照射小鼠脾细胞凋亡,降低脾细胞内的caspase-3活性,降低脂质过氧化物水平。结论葛根黄酮具有明显的辐射防护作用,效果明显优于愈风宁心片。葛根黄酮抗辐射作用机制可能与抑制辐射敏感细胞的细胞凋亡和抗氧化作用有关。

Objective To investigate radiation protection of Pueraria Flavonid and its molecular mechanism. Methods Kunming mice were intragaatrically （ig） administered with Pueraria Flavonid before exposure to ^60Coγ-ray radiation of 5 Gy. Thirty day survival and average life span of dead mice after irradiation were estimated. Peripheral blood parameters, the organ indexes of thymus and spleen and antioxidant activity were also observed in the irradiated mice. The apoptosis of spleen cells in irradiated mice was detected by FACS and in situ terminal labeling method. The effect of Pueraria Flavonid on the activities of caspase-3 in spleen cells were examined. Results Administration with Pueraria Flavonid increased the 30-day survival and prolonged the average life span of the dead mice. The increases in the number of white blood cells and the organ indexes of thymus and spleen, the decreases in apoptosis rates and caspase-3 activities in spleen cells were observed in Pueraria Flavonid treated group. Cu/Zn-SOD activity was increased and MDA levels significant decreased with a, rlministration of Pueraria Flavonid. Conclusions Pueraria Flavonid performs function in radiation protection, and the underlying mechanism might be related with suppression of apoptosis and antioxidant activity in radiationsensitive cells.