细胞凋亡拮抗剂AS1501对急性放射病小鼠的保护作用研究  

Protective effect of apoptosis antagonist AS1501 against acute radiation sickness mice

作　　者：曹琳超 赵丹阳 郑颖 甘慧 孟志云 窦桂芳 顾若兰 CAO Lin-chao;ZHAO Dan-yang;ZHENG Ying;GAN Hui;MENG Zhi-yun;DOU Gui-fang;GU Ruo-lan(Institute of Radiation Medicine,Academy of Military Medical Sciences,Academy of Military Sciences,Beijing 100850,China)

机构地区：[1]军事科学院军事医学研究院辐射医学研究所,北京100850

出　　处：《军事医学》2022年第10期726-731,736,共7页Military Medical Sciences

基　　金：北京市自然科学基金(7202148)。

摘　　要：目的为研究死亡受体5(DR5)介导的细胞凋亡在放射损伤效应中的作用及其作为放射损伤防护药物研发新靶标的可行性,采用重组表达的DR5细胞凋亡拮抗剂(AS1501)对^(60)Co-γ射线单次全身照射急性放射病(ARS)小鼠的治疗效果进行评价。方法45只C57BL/6小鼠随机分成模型对照组、阳性对照组、AS1501低(5 mg/kg)、中(10 mg/kg)、高(15 mg/kg)剂量给药组,观察不同剂量AS1501对8.5 Gy ^(60)Co-γ射线照射后小鼠3个月长期生存率的影响;63只C57BL/6小鼠随机分成正常对照组、AS1501治疗组和模型对照组,AS1501组经4.0 Gy ^(60)Co-γ射线单次全身照射后尾静脉注射AS1501(15 mg/kg),各组动物分别于照射后2 h,1和4 d流式细胞仪检测骨髓造血干/祖细胞(LSK/LK)数量;照射后2 h,1、4、7、11和14 d细胞计数检测骨髓有核细胞(BMNC)数量,称重法计算脾脏及胸腺脏器指数;照射后第3天取小鼠胸腺组织,免疫荧光双标记检测小鼠受照射前后及AS1501给药后胸腺组织中DR5蛋白表达及细胞凋亡水平。结果AS1501能有效提高极重度骨髓型ARS小鼠3个月生存率,且呈明显剂量依赖性;与模型对照组比较,AS150115 mg/kg可显著增加ARS小鼠照射后第1~11天的胸腺重量、胸腺指数及骨髓BMNC水平(P<0.05),促进照射后2 h骨髓LSK/LK水平恢复;免疫荧光双标记结果显示,照射后3 d小鼠胸腺组织中DR5蛋白表达和细胞凋亡水平均显著上调,AS1501可有效抑制胸腺细胞凋亡水平。结论DR5细胞凋亡拮抗剂AS1501能有效减轻ARS小鼠造血免疫系统的早期损伤,促进免疫器官功能恢复,提高极重度骨髓型ARS小鼠生存率,提示TRAIL-DR5介导的细胞凋亡可能在急性放射损伤效应中发挥重要作用。Objective To study the role of death receptor 5(DR5)-mediated apoptosis in radiation injury and the feasibility of DR5 being used as a potential target for the development of new anti-radiation drugs.Methods Forty-five C57BL/6 mice were randomly divided into the model control group,normal control group,positive control group,AS1501 low(5 mg/kg),medium(10 mg/kg)and high dose groups(15 mg/kg)respectively.The 3-month survival rate of different groups after exposure to 8.5 Gy 60Co-γray was observed.After mice were treated with 4.0 Gy 60Co-γray single whole-body irradiation,AS150115 mg/kg was injected into the caudal vein at 2 h,1 d,4 d,7 d,11 d and 14 d post-irradiation.The number of bone marrow nucleated cells(BMNCs)was measured by cell count and the organ indexes of the spleen and thymus were calculated.The number of bone marrow hematopoietic stem/progenitor cells(LSK/LK)was measured by flow cytometry at 2 h,1 d and 4 d post-irradiation.The immunofluorescence double labeling was used to detect the changes in expressions of DR5 protein and the apoptosis levels in the thymus at 3 d post-irradiation.Results AS1501 could effectively increase the 3-month survival rate of ARS mice after high-dose 60Co-γray irradiation,in a dose-dependent manner.The administration of AS150115 mg/kg could significantly increase the organ indexes of the thymus and promote BMNC in ARS mice at 1-11 d post-irradiation(P<0.05).The LSK/LK level was also significantly increased at 2 h post-irradiation(P<0.05).Immunofluorescence double labeling test showed that the expression of DR5 protein and the level of apoptosis in thymus tissue of ARS mice were obviously up-regulated at 3 d post-irradiation,and that AS1501 could inhibit the level of apoptosis in thymus tissue of the ARS mice.Conclusion DR5 apoptosis antagonist AS1501 can effectively reduce the early injury to the hematopoietic immune system in ARS mice,promote the recovery of immune organs,and improve the survival rate of ARS mice of the severe bone marrow type,suggesting that TRAIL-DR5 m

关 键 词：死亡受体5 放射损伤 放射防护 急性放射病 细胞凋亡拮抗剂 

分 类 号：R818[医药卫生—放射医学] R979.6[医药卫生—临床医学]