不同剂量率^(60)Coγ射线照射对人外周血辐射敏感基因表达变化的影响  

Dose-rate effect on radiation-induced gene expressions in human peripheral blood

作　　者：李爽[1] 陆雪[1] 蔡恬静[1] 田梅[1] 刘青杰[1] Li Shuang;Lu Xue;Cai Tianjing;Tian Mei;Liu Qingjie(Key Laboratory of Radiological Protection and Nuclear Emergency,China CDC,National Institute for Radiological Protection,Chinese Center for Disease Control and Prevention,Beijing 100088,China)

机构地区：[1]中国疾病预防控制中心辐射防护与核安全医学所辐射防护与核应急中国疾病预防控制中心重点实验室,北京100088

出　　处：《中华放射医学与防护杂志》2021年第7期481-485,共5页Chinese Journal of Radiological Medicine and Protection

基　　金：国家自然科学基金(81803162)。

摘　　要：目的探讨不同剂量率^(60)Coγ射线照射对辐射诱导的基因表达水平改变的影响。方法^(60)Coγ射线照射3例正常人离体外周血,剂量率分别为0.2、1.0和2.0 Gy/min,照射剂量为0、1、2、4和6 Gy,照射后24 h收集细胞,实时荧光定量(PCR)法对11个基因(CDKN1A、MDM2、PCNA、FDXR、GADD45A、PHPT1、ASTN2、TNFSF4、POLH、GDF-15和PPM1D)mRNA表达水平进行相对定量检测;逐步回归法构建不同剂量率基因组合表达模型。结果不同剂量率0.2、1和2 Gy/min ^(60)Coγ射线照射后,辐射诱导的11个基因的相对表达量随照射剂量增加而升高,具有显著的剂量依赖性(R2=0.744~0.998,P<0.05);0.2 Gy/min ^(60)Coγ射线照射2 Gy后,CDKN1A、FDXR、PHPT1和TNFSF4基因的表达量明显高于1和2 Gy/min剂量率组,差异具有统计学意义(t=3.73、5.73、2.44、2.77、3.53、2.68、2.43、2.05,P<0.05);2 Gy/min ^(60)Coγ射线照射6 Gy后,PPM1D基因表达量明显高于其他两个剂量率组(t=3.82、2.54,P<0.05);不同剂量率基因组合表达模型由2~3个基因组成,回归方程的R2值为0.951~0.976(P<0.05)。结论在0.2~2 Gy/min剂量率范围内,不同剂量率^(60)Coγ射线照射可能会影响辐射诱导人外周血基因表达水平的改变。Objective To explore the influence of dose-rate on radiation-induced gene expression in human peripheral blood.Methods Human peripheral blood ex vivo was irradiated with 0,1,2,4 and 6 Gy of ^(60)Coγ-rays with different dose-rates of 0.2,1 and 2 Gy/min.Human blood cells were harvested at 24 h post-irradiation.Following RNA isolation,the mRNA expression levels ofCDKN1A,MDM2,PCNA,FDXR,GADD45A,PHPT1,ASTN2,TNFSF4,POLH,GDF-15 and PPM1D were measured by quantitative real-time PCR.The stepwise regression method was used to establish the gene combination models.Results The relative mRNA expression levels of 11 genes significantly increased in a dose-dependent manner within the dose range of 0-6 Gy with three dose-rates of irradiation(R2=0.744-0.998,P<0.05).Following the exposure to 2 Gy(0.2 Gy/min) ^(60)Coγ-rays,the expression levels of CDKN1A,FDXR,PHPT1 and TNFSF4 genes were significantly higher than that of the 1 and 2 Gy/min groups(t=3.73,5.73,2.44,2.77,3.53,2.68,2.43,2.05,P<0.05).With 6 Gy irradiation,the changes of radiation-induced PPM1D expression level under a dose rate of 2 Gy/min were significantly higher than other two dose-rates(t=3.82,2.54,P<0.05).The combined expression model at different dose rates was composed of 2-3 genes,and the R2values of regression equations were 0.976,0.964 and 0.951,respectively.Conclusions In a certain range,the dose-rate may affect the changes of radiation-induced gene expression in human peripheral blood.

关 键 词：电离辐射 基因表达 剂量率 

分 类 号：R818[医药卫生—放射医学]