辐射诱导细胞内凝溶胶蛋白变化及其对小鼠氧化损伤的影响

The changes of gelsolin in irradiated cells and its effects on oxidative injury of mice

为研究凝溶胶蛋白(Gelsolin)在辐射损伤中的作用,以6、8和12 Gyγ射线分别照射BALB/c小鼠和人小肠上皮隐窝细胞(HIEC)。于照后不同时间抽提HIEC全蛋白,Western blot半定量法检测胞浆型Gelsolin(cGSN)蛋白相对含量。照射后24 h给受照小鼠注射重组人源Gelsolin蛋白,不同照后时间收集小鼠血液。检测血浆中丙二醛(MDA)、超氧化物歧化酶(SOD)和谷胱甘肽(GSH)含量。结果显示8 Gy剂量组照射后2-12 h,HIEC细胞cGSN相对表达均低于正常水平,照后24 h时则高于正常水平,其中照后12 h变化与正常水平相比差异显著(p<0.05)。12 Gy剂量组照后2 h cGSN相对表达低于正常水平,照后4-24 h高于正常水平,其中照后6 h和12 h变化与正常水平比差异显著(p<0.05)。BALB/c小鼠6 Gy剂量组照射后2和7 d时,Gelsolin给药组GSH、SOD显著高于单纯照射对照组(p<0.05),MDA显著低于单纯照射对照组(p<0.05)。推论,外源性补充Gelsolin对辐射所致氧化性损伤具有一定缓解作用。

The changes of gelsolin in irradiated cells and its effects on oxidative injury of irradiated mice were investigated. The relative expression levels ofcGSN in cultured human intestinal epithelial cells （HIEC） irradiated by 137Cs γ-rays with 8 Gy and 12 Gy were detected by western blot assay. BALB/c mice were divided randomly into gelsolin group treated with gelsolin, irradiated group and normal control group. Then the contents of plasma malonaldehyde （MDA）, superoxide dismutase （SOD） and whole blood glutathione （GSH） were examined at 2 d and 7 d after irradiation of 6 Gy γ-rays. The relative level of cGSN in HIEC exposed to 8 Gy was lower than that of the normal level from 2 to 12 h post-radiation （the difference between post-irradiation observed at 12 h and normal level was sig- nificant, p〈0.05）, but higher than that of the normal level observed at 24 h post-radiation. The level of cGSN in HIEC exposed with 12 Gy was also lower than that of normal level determined at 2 h post-radiation but higher than that of the normal level from 4 to 24 h post-radiation. （The differences at 6 and 12 h time points comparing to the normal level were statistical significant respectively, p〈0.05）. Plasma levels of GSH and SOD in gelsolin treated mice after exposure to 6 Gy irradiation were obviously higher than that of irradiation treated groups at 2 and 7 d （p〈0.05）, whereas MDA level was significantly lower than that of only irradiation treated groups （p〈0.05）. Gelsolin might be able to protect mice against oxidative injury induced by radiation.