摘要
目的:探讨低剂量电离辐射与小鼠睾丸细胞内质网应激的发生以及PERK-CHOP通路激活的相关性。方法:健康雄性昆明小鼠随机分成时程-效应(75 mGy照射后0、3、6、12和24 h)和剂量-效应(0、50、75、100和200 mGy照射后12 h)组,每组动物10只。采用H2O2和MDA试剂盒比色法检测其含量;利用实时定量逆转录PCR(quantitative RT-PCR)检测GRP78、PERK和CHOP mRNA;Western印迹和图像分析技术检测GRP78、PERK、磷酸化PERK(phosphorylated PERK,pho-PERK)和CHOP蛋白表达。结果:小鼠经75 mGy全身照射后,睾丸组织中H2O2含量随时间延长而增加,MDA含量在3和6 h稍有降低,而后随时间延长而增加,二者在12和24 h较0 h时显著增加(P<0.05,P<0.01);除了GRP78 mRNA(3和24 h)和蛋白表达(6 h)分别在照射后有降低趋势外,GRP78(12 h)、PERK(3、6、12和24 h)和CHOP(12和24 h)的mRNA表达较0 h显著增加(P<0.05,P<0.01),GRP78(12和24 h)、pho-PERK(3、12和24 h)和CHOP(3、6、12和24 h)的蛋白表达也都较0 h显著增加(P<0.05,P<0.01),PERK蛋白表达则无明显变化规律。小鼠经50～200 mGy全身照射后12 h,睾丸组织中H2O2含量在50～100 mGy照射后随剂量增加而增加,200 mGy照射后则稍有降低,MDA含量随剂量增加而增加,而且H2O2含量(75和100 mGy)和MDA含量(75、100和200 mGy)显著高于0 mGy组(P<0.05,P<0.01);除了GRP78mRNA表达在50和200 mGy照射后有降低趋势外,GRP78(75和100 mGy)、PERK(75、100和200 mGy)和CHOP(50、75、100和200 mGy)的mRNA表达都显著高于0 mGy组(P<0.05,P<0.01),GRP78(100和200 mGy)、pho-PERK(50、100和200 mGy)和CHOP(50、75、100和200 mGy)的蛋白表达也都显著高于0 mGy组(P<0.05,P<0.01),而PERK蛋白表达则无明显变化规律。结论:低剂量电离辐射能够诱导小鼠睾丸细胞发生内质网应激,并且激活PERK-CHOP信号通路。
Objective： To explore the correlation of low-dose radiation with endoplasmic reticulum stress and the activation of the PERK-CHOP signaling pathway in mouse testicular cells.Methods： Healthy Kunming mice were randomly assigned to time-effect（0,3,6,12 and 24 h of irradiation at 75 mGy） and dose-effect（12 h of irradiation at 0,50,75,100 and 200 mGy） groups.The contents of H2O2 and MDA were measured by colorimetry with the agent kits,the expressions of GRP78,PERK and CHOP mRNA detected by quantitative RT-PCR,and the levels of GRP78,PERK,phosphorylated PERK（pho-PERK） and CHOP proteins determined by Western blotting and image analysis.Results： After whole-body irradiation of the mice with 75 mGy,the content of H2O2 in the testis tissue was increased with time prolongation,while that of MDA decreased slightly at 3 and 6 h and then increased with the lengthening of time,both increased significantly at 12 and 24 h as compared with those at 0 h（P 〈 0.05,P 〈 0.01）.Apart from reduced levels of GRP78 mRNA at 3 and 24 h and GRP78 protein at 6 h after irradiation,significant increases were found in the mRNA expressions of GRP78 at 12 h,PERK at 3,6,12 and 24 h and CHOP at 12 and 24 h（P 〈 0.05,P 〈 0.01）,as well as in the protein levels of GRP78 at 12 and 24 h,pho-PERK at 3,12 and 24 h and CHOP at 3,6,12 and 24 h in comparison with those at 0 h（P 〈 0.05,P 〈 0.01）.No obvious regularity was observed in the change of the PERK protein expression.After 12 h of whole-body irradiation,the content of H2O2 was increased at 50,75 and 100 mGy,but decreased slightly at 200 mGy,while that of MDA was increased with dose increasing,with significant increases in the content of H2O2 at 75 and 100 mGy and in that of MDA at 75,100 and 200 mGy as compared with the 0 mGy group.Apart from the reduced levels of GRP78 mRNA at 50 and 200 mGy,significant increases were found in the mRNA expressions of PERK at 75,100 and 200 mGy and CHOP at 50,75,100 and 200（P 〈 0.05,P 〈 0.01） as well as in the protein levels of GRP78 at 100 and 200 mGy,pho-PERK at 50,100 and 200 mGy and CHOP at 50,75,100 and 200 mGy as compared with those at 0 mGy（P 〈 0.05,P 〈 0.01）.There were differences in the changes of different protein expressions,but no obvious regularity was seen in the change of the PERK protein expression.Conclusion： Low-dose radiation can induce endoplasmic reticulum stress in mouse testicular cells,and activate the PERK-CHOP signaling pathway.
出处
《中华男科学杂志》
CAS
CSCD
2012年第9期777-782,共6页
National Journal of Andrology
基金
国家自然科学基金(30970681)
吉林大学科学前沿与交叉学科创新项目(200903116)~~
关键词
低剂量电离辐射
内质网应激
PERK
CHOP
睾丸细胞
low-dose radiation； endoplasmic reticulum stress； PKR-like ER kinase； C/EBP homologous protein； testicular cell；
