阿霉素诱导心肌病小鼠模型的构建

doi:10.19401/j.cnki.1007-3639.2022.10.003

摘要/Abstract

摘要：

背景与目的：阿霉素又称多柔比星，是临床实践中治疗各种肿瘤中有效、应用广泛的细胞毒性化疗药物之一，属于蒽环类抗肿瘤药物。然而该药物会引起严重的不良反应，特别是剂量依赖性心脏毒性，因而成为肿瘤心脏病学领域颇受关注的问题。目前国际上尚无公认、统一、稳健的阿霉素诱导心肌病模型的构建方法。为探讨最佳给药剂量及频次构建阿霉素诱导急性心肌病设计本实验。方法：40只8 ~ 10周龄雄性C57BL/6J小鼠随机分为4组：对照组（control，CON）给予等量生理盐水腹腔注射，以及在阿霉素累积剂量相同的情况下，根据不同给药剂量及频次的M1组（单次给药15 mg/kg）、M2组（单次5 mg/kg，连续3d给药）、M3组（单次7.5 mg/kg，隔天给药，共2次）腹腔注射阿霉素构建阿霉素诱导急性心肌病模型。分别从小鼠一般生命体征、体重变化和存活率、心脏超声、体表心电图、N末端B型利钠肽原（N-terminal pro-B-type natriuretic peptide，NT-proBNP）、心肌肌钙蛋白I（cardiac troponin I，cTnI）及心肌组织形态改变等方面综合评估造模效果。结果：与CON相比，M1、M2、M3组小鼠体重均显著下降（P<0.001）；M3组较M1和M2组存活率更高（80% vs 40%、50%，P<0.05）。相较于CON、M1组和M2组，体表心电图显示M3组PR间期[（0.064 2±0.003 8）s vs（0.042 3±0.000 9）s、（0.052 7±0.007 9）s和（0.062 0±0.001 2）s，P均<0.05]、QT间期[（0.047 5±0.000 2）s vs （0.022 0±0.000 9）s、（0.038 6±0.004 4）s和（0.044 4±0.003 0）s，P均<0.05]显著延长；心脏超声检查结果显示，M3左心室射血分数显著下降（40.40%±2.24% vs 54.72%±1.64%、46.00%±4.41%和54.68%±3.38%，P均<0.05），M3左心室短轴缩短率显著下降（19.40%±1.20% vs 27.88%±1.05%、22.57%±2.50%和27.86%±2.20%），差异有统计学意义（P均<0.05）；心脏标志物检测显示，与CON相比，阿霉素给药组M1组、M2组、M3组血清NT-proBNP水平显著升高[（638.13±12.69）pg/mL vs（1 271.36±11.76）pg/mL、（1 270.85±36.19）pg/mL和（1 225.26±24.19）pg/mL，P均<0.05）。组织形态学显示，M3心肌细胞空泡化程度及数量显著高于CON、M1和M2（81个/视野 vs 3个/视野、65个/视野、34个/视野，P<0.05）。结论：腹腔注射阿霉素诱导急性心肌病模型的方法简便、可靠；阿霉素腹腔注射剂量7.5 mg/kg，隔天给药2次，累积剂量15 mg/kg模型最理想。

关键词: 阿霉素心脏毒性, 心肌病, 肿瘤心脏病, 模型

Abstract:

Background and purpose: Adriamycin also named as doxorubicin, is one of the most widely used cytotoxic chemotherapeutic agents for clinical practice for the treatment of various tumors, and belongs to anthracycline antitumor drugs. Unfortunately, this drug will cause serious side effects, especially dose-dependent cardiotoxicity, which has become a concern in the field of onco-cardiology. At present, there is no universally recognized, unified and robust method to construct Doxorubicin-induced cardiomyopathy model. This experiment was designed to explore the optimal dose and frequency of doxorubicin-induced cardiomyopathy in a mouse model.Methods: Forty 8-10-week-old male C57BL/6J mice were randomly divided into 4 groups (control group and 3 model groups). The model group was divided into model 1 (M1) group (15 mg/kg, single dose) and M2 group (5 mg/ kg, once a day for 3 days continuously) and M3 group (7.5 mg/kg, twice on alternate days). General vital signs (body weight change and survival rate), echocardiography, body surface electrocardiogram (ECG), N-terminal pro-B-type natriuretic peptide (NT-proBNP), cardiac troponin I (cTnI) and myocardial tissue morphological changes were evaluated comprehensively.Results: Compared with the control group, the body weight of mice in M1, M2 and M3 groups decreased significantly (P<0.001); M3 group had higher survival rate than M1 and M2 group (80% vs 40% and 50%, P<0.05). Compared with the control group, M1 group and M2 group, the body surface ECG showed that the PR interval of M3 group [(0.064 2±0.003 8)s vs (0.042 3±0.000 9)s, (0.052 7±0.007 9) s and (0.062 0±0.001 2)s, P<0.05] and QT interval [(0.047 5±0.000 2)s vs (0.022 0±0.000 9)s, (0.038 6±0.004 4)s and (0.044 4±0.003 0)s, P<0.05] were significantly prolonged. Cardiac ultrasound showed that M3 ejection fraction decreased significantly (40.40%±2.24% vs 54.72%±1.64%, 46.00%±4.41% and 54.68%±3.38%, P<0.05). M3 short-axis shortening rate decreased significantly (19.40%±1.20% vs 27.88%±1.05%, 22.57%±2.50% and 27.86%±2.20%, P<0.05). Cardiac markers showed that compared with CON, the serum NT-proBNP levels of M1, M2 and M3 in adriamycin group were significantly increased [(638.13±12.69) pg/mL vs (1 271.36±11.76) pg/mL, (1 270.85±36.19) pg/mL and (1 225.26±24.19) pg/ mL, P<0.05]. Histomorphology showed that the vacuoles in cardiomyocyte of M3 group was significantly increased compared with CON, M1 and M2 group (81/field vs 3/field, 65/field and 34/field, P<0.05).Conclusion: Intraperitoneal injection of adriamycin in acute heart failure model is simple and reliable. The model in which adriamycin is administered by intraperitoneal injection at a dose of 7.5 mg/ kg, twice on alternate days, with cumulative dose of 15 mg/kg is optimal.

Key words: Adriamycin-induced cardiotoxicity, Cardiomyopathy, Onco-cardiology, Model

中图分类号:

R542.2

张庆领, 张云鹏, 周赞东, 张跃, 刘彤. 阿霉素诱导心肌病小鼠模型的构建[J]. 中国癌症杂志, 2022, 32(10): 948-959.

ZHANG Qingling, ZHANG Yunpeng, ZHOU Zandong, ZHANG Yue, LIU Tong. Construction of a mouse model of adriamycin-induced cardiomyopathy[J]. China Oncology, 2022, 32(10): 948-959.

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Reference	Cumulative dose	Mode of administration
^[17]	7 mg	1 mg/kg, once a day for continued 7 days
^[15,18]	15 mg	15 mg/kg, once
^[19]		2.5 mg/kg, every other day, six times in a row
^[15]		5 mg /kg, once a week for 3 weeks
^[16]		7.5 mg/kg, twice on alternate days
^[20]	16 mg	4 mg/kg, once a week for 4 weeks
^[21]	18 mg	6 mg/kg, via tail vein at day 0, 2, and 4
^[22-23]	20 mg	5 mg/kg, once a week for 4 weeks
^[24]		20 mg/kg, once
^[25]	24 mg	6 mg/kg, once a week for 4 weeks
^[26-27]	25 mg	5 mg/kg, once a week for 5 weeks

Item	CON	M1	M2	M3
LVID^d/mm	3.752 4±0.133 9	3.738 9±0.152 0	3.427 8±0.157 4	3.247 3±0.229 8
LVID^s/mm	2.706 6±0.104 7	2.707 0±0.142 0	2.470 1±0.124 2	2.486 2±0.180 3
LVPW^d/mm	0. 715 0±0.045 7	0.639 3±0.056 6	0.710 2±0.013 1	0.717 2±0.048 3
LVPW^s/mm	0.990 9±0.027 5	0.686 3±0.019 6	0.916 1±0.030 3	0.927 0±0.071 7
IVS^d/mm	0.787 2±0.075 6	0.822 8±0.100 7	0.778 2±0.049 9	0.727 3±0.053 9
IVS^s/mm	1.200 4±0.039 3	1.130 3±0.182 4	0.951 7±0.027 9	0.940 5±0.046 2
LVEF/%	54.722 9±1.635 1	46.009 3±4.413 7	54.684 3±3.375 4	40.396 6±2.240 7^*
LVFS/%	27.880 8±1.050 3	22.568 3±2.503 1	27.857 9±2.202 7	19.395 5±1.207 5^*
P wave duration/s	0.014 0±0.001 3	0.012 0±0.000 7	0.012 1±0.000 3	0.015 3±0.001 2
PR interval/s	0.042 3±0.000 9	0.052 7±0.007 9	0.062 0±0.001 2	0.064 2±0.003 8^**
QRS duration/s	0.011 2±0.001 0	0.010 5±0.000 8	0.010 5±0.000 1	0.010 3±0.000 6
QT interval/s	0.022 0±0.000 9	0.038 6±0.004 4^*	0.044 4±0.003 0^**	0.047 5±0.000 2^**
QTc interval/s	0.041 9±0.002 0	0.072 1±0.007 5^*	0.848 1±0.003 4^**	0.637 7±0.004 2^*
RR interval^s/s	0.148 5±0.008 6	0.152 2±0.007 6	0.143 3±0.011 7	0.164 8±0.017 5