低聚壳聚糖对小鼠的辐射损伤防护作用探讨

探讨低聚壳聚糖对受γ射线照射小鼠辐射损伤防护作用。采用γ射线照射小鼠,检测骨髓有核细胞数、淋巴细胞凋亡数、脾脏脏器系数、细胞凋亡相关基因和P53蛋白、GADD45蛋白变化。流式细胞仪检测细胞凋亡,RT-PCR技术检测凋亡基因,Western blot方法检测蛋白表达。结果表明,与单纯照射组相比,低聚壳聚糖能提高受照小鼠的存活率;提高骨髓有核细胞数,降低骨髓淋巴细胞凋亡细胞数量;下调脾脏凋亡相关基因Bax、caspas-3,上调Bc1-2,Bcl-2/Bax比值升高;抑制P53蛋白、GADD45蛋白表达。结果提示,低聚壳聚糖可能通过抑制P53蛋白、GADD45蛋白表达,影响凋亡相关基因表达,抑制凋亡细胞的产生,促进造血功能恢复,从而起到保护受照损伤小鼠作用。

Discussion on the Protective Effect of Oligochitosan on Radiation Damage in Mice

The protective effect of oligochitosan on radiation damage in mice exposed to gamma rays was explored by means of flow cytometry,RT-PCR,Western blotting. The changes in bone marrow nucleated cells,lymphocyte apoptosis,spleen organ coefficient,cell apoptosis-related genes,P53 protein and GADD45 protein were tested. As compared with the control group,γ-ray exposed mice with a gavage of oligochitosan showed an improved survival rate,increase numbers of bone marrow nucleated cells,reduced numbers of apoptotic cells in bone marrow lymphocytes. For the test group,oligochitosan was observed to be able to down-regulate Bax,caspas-3 and up-regulate Bc1-2 for apoptosis-related genes,which give rise to anincreased Bcl-2/Bax ratio,and inhibite expression of P53 protein and GADD45 protein also. It suggests that oligochitosan may inhibit the expression of P53 protein and GADD45 protein,affect the expression of apoptosis-related genes,inhibit the production of apoptotic cells,and promote haematopoietic function recovery,and thus protect mice from radiation damage.