相同剂量分割照射与单次照射对小鼠放射性心脏损伤的影响
Effects of the same dose of fractionated radiation and single radiation on the modeling of radiation-induced heart damage in mice
曹虎 1王唱垚 2邵靖媛 1刘杰 3王溢豪 3何智超 4胡舜英 3王华1
作者信息
- 1. 军事科学院军事医学研究院,北京 100850
- 2. 军事科学院军事医学研究院,北京 100850;河北大学生命科学学院,河北保定 071002
- 3. 解放军总医院心血管病医学部,北京 100853
- 4. 军事科学院军事医学研究院,北京 100850;安徽医科大学生命科学学院,合肥 230032
- 折叠
摘要
目的 探索相同剂量分割照射与单次照射对小鼠放射性心脏损伤的影响.方法 野生型C57BL/6J小鼠21只,随机分为正常对照组、分割照射组和单次照射组.采用18 GyX射线,对小鼠心脏分别进行分割(3Gy/次,6次)和单次照射,建立放射性心脏损伤模型.照射后7和28 d通过全自动生化分析仪检测小鼠心肌酶损伤标志物肌酸激酶(CK)、肌酸激酶同工酶MB(CK-MB)、乳酸脱氢酶(LDH)和LDH1,以及外周血清离子(K+、Ca2+、Fe2+和Cl-)的浓度;照射后28 d检测小鼠心脏功能,记录并分析左心室射血分数(EF)、左心室短轴缩短率(FS)、左心室舒张末期容积(LVEDV)、左心室质量(LV mass)和左心室收缩末期容积(LVESV)的变化;激光共聚焦显微镜观察心肌细胞线粒体膜通道孔(mPTP)开放和线粒体膜电位的改变;透射电镜观察心肌超微结构;Masson染色观察心肌纤维化;油红染色观察主动脉粥样硬化;实时定量PCR(RT-qPCR)和Western印迹检测凋亡相关基因与蛋白B细胞淋巴瘤-2相关蛋白X(BAX)和胱天蛋白酶3(casepase-3)的表达.结果 18 Gy X射线照射后7 d,单次照射组小鼠CK、CK-MB、LDH和LDH1的表达水平均显著升高或有升高趋势,而分割照射组仅有CK和LDH1出现升高趋势.照射后28 d,2种照射方式均可导致心肌酶谱4种酶的表达水平升高.照射后7和28 d,2种照射方式均可导致血清离子K+、Fe2+、Ca2+和Cl-的浓度明显降低.2种照射方式都会导致EF和FS降低,LV mass、LVEDV和LVESV升高,2组之间EF和FS的差别具有统计学意义.分割照射和单次照射均会导致mPTP和膜电位的降低,其中单次照射组的改变更加显著,2组之间的差异具有统计学意义.电镜观察发现,X射线照射后心肌细胞线粒体嵴减少,空泡化形成以及心肌纤维束增粗.Masson染色可见,X射线照射后小鼠心肌组织胶原纤维沉积,单次照射组更明显.主动脉大体油红染色发现,2种照射方式均会对小鼠主动脉造成损伤,单次照射组粥样硬化斑块的面积比更大,与分割照射组之间差异存在统计学意义.RT-qPCR和Wester印迹结果显示,X射线照射可导致心肌组织凋亡相关BAX和casepase-3的表达水平增加,在核酸水平单次照射组升高更显著,与分割照射组之间的差异具有统计学意义.结论 相同剂量分割照射和单次照射都会造成小鼠心脏损伤,2种方式均可用于建立放射性心脏损伤模型;单次照射对小鼠心脏造成的损伤更加显著,可根据实际需求选择不同造模方式.
Abstract
Objective To explore the effects of the same dose of fractionated radiation and single radiation on radiation-induced heart damage in mice.Methods Twenty-one wild-type C57BL/6J mice were randomly divided into the normal group,fractionated radiation group and single radiation group.18 Gy X-ray,via fractionated(3 Gy/time,6 times)radiation or single radiation,was used to establish a radiation-induced heart damage model.The concentrations of myocardial enzyme damage markers(creatinekinase(CK),creatinekinase-MB(CK-MB),lactate dehydrogenase(LDH)and LDH1)and peripheral serum ions(K+,Ca2+,Fe2+and Cl-)were detected by an automatic biochemical analyzer at day 7 and 28 after radiation.Ultrasound was used to detect and analyze the cardiac function of mice at day 28 after radiation,including the left ventricular ejection fraction(EF),left ventricular fractional shortening(FS),left ventricular end-diastolic volume(LVEDV),left ventricular mass(LV mass)and left ventricular end-systolic volume(LVESV).The opening of the mitochondrial permeability transition pore(mPTP)and changes of mitochondrial membrane potential of myocardial cells were observed using a laser confocal microscope.The ultrastructure of myocardia was observed under a transmission electron microscope(TEM)and cardiac fibrosis was checked by Masson staining.The atherosclerosis of the aorta was examined by gross oil red staining.Real-time quantitative PCR(RT-qPCR)and Western blotting were performed to detect the expressions ofapoptosis-related genes and proteins,B cell lymphoma-2-associated X protein(BAX)and casepase-3.Results Seven days after 18Gy X-ray irradiation,the expression levels of CK,CK-MB,LDH and LDH1 in the single radiation group increased significantly or trended up,while only CK and LDH1 in the fractionated irradiation group continued to increase.Twenty-eight days after radiation,the expression levels of 4 enzymes in myocardial zymogram were increased by both radiation methods.Seven and twenty-eight days after radiation,the concentrations of serum ions K+,Fe2+,Ca2+and Cl-were significantly decreased by both radiation methods that could lead to the decrease of EF and FS,and the increase of LV mass,LVEDV and LVESV.Single radiation made more difference to EF and FS,and the difference between the two groups was statistically significant.Both methods could decrease the mPTP and mitochondrial membrane potential,especially single radiation,and there was significant difference between the two groups.The results of TEM showed that the mitochondrial cristae of myocardial cells decreased and vacuolated,and the myocardial fiber bundles became thicker after X-ray radiation.Masson staining showed that collagen fibers were deposited in the heart tissue ofmice after X-ray irradiation,particularly in the single radiation group.Gross oil red staining ofthe aorta showed that both methods could damage the aorta of mice,and the area of atherosclerotic plaques in the single radiation group was larger,which was statistically different from that of the fractionated radiation group.The results of RT-qPCR and Western blotting showed that X-ray radiation could increase the expression levels of apoptosis-related BAX and caspase-3 in cardiac tissue,especially in the single radiation group.The mRNAexpressions of BAX and caspase-3 increased more significantly in the single radiation group.Conclusion Both fractionated radiation and single radiation at the same dose can cause heart damage,so they can be used to establish a radiation-induced heart damage model of mice.Single radiation can cause more significant damage to the heart.Different modeling methods can be selected as required.
关键词
放射性心脏损伤/小鼠/动物模型/分割照射/单次照射Key words
radiation-induced heart damage/mouse/animal model/fractionated radiation/single radiation引用本文复制引用
基金项目
国家自然科学基金面上项目(82173450)
出版年
2024
国家科技期刊平台
NSTL
万方数据