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   复旦学报(医学版)  2019, Vol. 46 Issue (6): 726-732      DOI: 10.3969/j.issn.1672-8467.2019.06.002
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孙敏敏, 曹学森, 潘翠珍, 郭瑶, 谭笑, 舒先红. 二维斑点追踪显像(STI)评价硫酸吲哚酚(IS)对肾功能不全(CRF)大鼠的心脏毒性[J]. 复旦学报医学版, 2019, 46(6): 726-732.
SUN Min-min, CAO Xue-sen, PAN Cui-zhen, GUO Yao, TAN Xiao, SHU Xian-hong. Assessment of indoxyl sulfate (IS)-induced cardiotoxicity in rats with chronic renal failure (CRF) by speckle tracking imaging (STI)[J]. Fudan University Journal of Medical Sciences, 2019, 46(6): 726-732.
二维斑点追踪显像(STI)评价硫酸吲哚酚(IS)对肾功能不全(CRF)大鼠的心脏毒性
孙敏敏1,3,4 ▲, 曹学森2 ▲, 潘翠珍1,3,4 , 郭瑶1,3,4 , 谭笑2 , 舒先红1,3,4     
1. 复旦大学附属中山医院心超室 上海 200032;
2. 复旦大学附属中山医院肾内科 上海 200032;
3. 上海市影像医学研究所 上海 200032;
4. 上海市心血管病研究所 上海 200032
收稿日期：2018-07-23
基金项目：上海市卫计委科研课题青年基金项目（20174Y0054）；上海市自然科学基金面上项目（19ZR1450900）
摘要：目的 采用二维斑点追踪显像（speckle tracking imaging，STI）技术评价硫酸吲哚酚（indoxyl sulfate，IS）在肾功能不全（chronic renal failure，CRF）大鼠模型中的心脏毒性。方法 方法30只6周龄SD大鼠，随机入组肾功能不全CRF手术对照组、CRF+IS处理（IS）组和假手术（sham operation，SOR）组，每组10只。对CRF组和IS组实施5/6肾切除术建立肾功能不全模型，建模成功后，IS组给予隔天腹腔注射IS（100 mg/kg）约24周。每组大鼠在基线和注射结束1周时采集左室短轴二维超声图像，分析获得应变及应变率参数并进行组间及组内比较。实验完成后取心脏标本行病理学检查。结果 IS组中3只大鼠在IS注射12~20周中发生猝死，实验结束时SOR组10例，CRF组10例，IS组7例纳入统计分析。3组的左室内径均较基线明显增大，IS组和CRF组的室壁厚度均较基线明显增厚，IS组肥厚程度更为显著（P均 < 0.01）。实验前后，径向应变（radial strain，RS）在CRF组显著增加（P=0.017），但在IS组及SOR组差异无统计学意义。舒张功能参数环向应变率（circumferential peak E'/peak/A'，E'/A'-SRc）和径向应变率（radial peak E'/peak/A'，E'/A'-SRr）在IS组和CRF组均较基线显著降低，且实验后IS组显著低于CRF组（P均 < 0.01）。CRF组及IS组的心脏重量均显著大于SOR组（P均 < 0.05）。心肌细胞面积在SOR组、CRF组及IS组依次增大，且心肌纤维化程度在SOR组、CRF组和IS组依次增加（P均 < 0.05）。结论 IS可以加重肾功能不全大鼠的心肌损害，表现为心肌细胞的肥厚，坏死和纤维化，且左室舒张功能的下降早于收缩功能受损，应变率显像的舒张功能指标可敏感检测IS导致的左室舒张功能改变。
关键词：硫酸吲哚酚(IS)    心脏毒性    斑点追踪显像(STI)    应变    应变率    
Assessment of indoxyl sulfate (IS)-induced cardiotoxicity in rats with chronic renal failure (CRF) by speckle tracking imaging (STI)
SUN Min-min1,3,4 ▲, CAO Xue-sen2 ▲, PAN Cui-zhen1,3,4 , GUO Yao1,3,4 , TAN Xiao2 , SHU Xian-hong1,3,4     
1. Department of Echocardiography, Fudan University, Shanghai 200032, China;
2. Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai 200032, China;
3. Shanghai Medical Imaging Institute, Shanghai 200032, China;
4. Shanghai Institute of Cardiovascular Disease, Shanghai 200032, China
Foundation item: This work was supported by the Youth Foundation of Shanghai Municipal Commission of Health and Family Planning (20174Y0054) and the General Program of Shanghai Natural Science Foundation (19ZR1450900)
Corresponding author: SHU Xian-hong, E-mail:shu.xianhong@zs-hospital.sh.cn.
▲SUN Min-min and CAO Xue-sen contributed equally to this work
Abstract: Objective To investigate the cardiotoxicity of indoxyl sulfate (IS) in a chronic renal failure (CRF) rat model by speckle tracking imaging (STI). Methods Thirty SD rats aged 6 weeks were divided into 3 groups, including CRF group, CRF+IS group and sham operation (SOR) group (n=10 for each).The 5/6 nephrectomy was performed on CRF and IS groups to build CRF model.After modeling success, IS group was given intraperitoneal injection of IS (100 mg/kg) every other day for up to 24 weeks.Echocardiography was performed at baseline and 1 week after the end of IS treatment.Strain and strain rate of left ventricular short axis were compared between-group and intra-group based on STI analysis.After the experiment, the heart specimens were taken for pathological examination. Results Sudden death occurred in 3 rats in IS group during 12-20 weeks of IS injection.At the end of the experiment, 10 cases in SOR group, 10 cases in CRF group and 7 cases in IS group were included in the statistical analysis.Left ventricular end-diastolic diameter (LVEDD) was enlarged in all the 3 groups.Left ventricular wall thickness (LVWT) was increased in IS group and CRF group and the increases were more notable in IS group (all P < 0.01).Radial strain (RS) was increased in CRF group (P=0.017), while no significant difference was found in IS group and SOR group compared with the baseline data.Both circumferential peak E'/peak A' (E'/A'-SRc) and radial peak E'/peak A' (E'/A'-SRr) decreased in CRF group and IS group, and the decreases were more significant in IS group compared with CRF group (all P < 0.01).The heart weights were increased in CRF group and IS group compared with SOR group (all P < 0.05).Histological analysis showed myocardial hypertrophy, necrosis, fibrosis happened in CRF and IS group, and the areas of myocardial cells were in ascending order of SOR, CRF and IS groups (all P < 0.05). Conclusions IS exposure can aggravate myocardial hypertrophy, necrosis and fibrosis in CRF rats.Left ventricular diastolic dysfunction happened earlier than systolic dysfunction.Left ventricular diastolic functional parameters provided by STI could sensitively detect IS-induced myocardial injury.
Key words: indoxyl sulfate (IS)    cardiotoxicity    speckle tracking imaging (STI)    strain    strain rate    

心血管并发症是终末期肾病(end-stage renal disease, ESRD)患者的首要死因[1], 传统心血管疾病危险因素不能完全解释患者心血管死亡风险显著增加。尿毒症毒素是ESRD患者心血管并发症的独立危险因素[2]。硫酸吲哚酚(indoxyl sulfate, IS)作为一种代表性蛋白结合肾脏毒素, 在患者体内升高最早且最明显, 常规透析方法无法清除, 在动脉粥样硬化和心肌肥厚过程中参与关键步骤[3-4]。IS在体外可引起心肌细胞肥厚及成纤维细胞纤维合成增加[5], 在高血压大鼠模型中IS可通过氧化应激促进心肌细胞纤维化[6], 故无创性超声心动图监测IS引起的心脏重构和功能改变对临床意义重大。斑点追踪显像(speckle tracking imaging, STI)基于高帧频灰阶超声图像, 实时跟踪心肌内回声斑点的空间运动, 时间及空间分辨率较高, 无角度依赖性[7-8]。本研究采用5/6肾切除SD大鼠模型, 通过外源性IS诱导, 明确IS作用下在体心脏的形态、功能及病理改变, 同时采用STI技术对大鼠的左室功能进行评估, 以探测其应用价值。

资料和方法

实验试剂  麻醉用5%戊巴比妥钠(国药集团化学有限公司); 0.9%氯化钠注射液(百特制药有限公司); 硫酸吲哚酚(美国Sigma公司)。

仪器和分析软件  Vivid E9心脏超声诊断仪(美国GE公司)配备12S探头(11 MHz), 数据分析采用EchoPac BT12工作站。

研究对象  30只6周龄SD大鼠, 体质量为(220±20)g, 由复旦大学上海医学院动物实验中心提供和笼养, 室温和相对湿度恒定, 食物及水源供应充足。随机分为3组, 每组10只, 即假手术(sham operation, SOR)组、肾功能不全手术对照(chronic renal failure, CRF)组和CRF+IS处理组。本研究获得复旦大学实验动物关怀和利用委员会的许可。

研究方法

动物模型制备及实验流程  采用5/6肾切除术[9]建立肾功能不全大鼠模型。一期手术采用5%戊巴比妥钠(50 mg/kg)腹腔注射麻醉, 左肾被腹正中暴露切开, 暴露左肾, 剥离肾包膜, 将左肾上下级各1/ 3切除, 明胶海绵压迫止血并缝合。一期手术后1周行二期手术, 同样方法麻醉, 右侧背部切开暴露右肾, 结扎肾蒂, 摘除右肾。SOR组与5/6肾切除术组动物同期进行二次手术, 仅切开并剥离肾包膜暴露肾脏后关腹。术后6周(13周龄)采集血液标本, 测血肌酐较基线上升2~3倍, 建模成功。IS组隔天腹腔注射IS(100 mg/kg)[10]24周, 每次注射前配置IS溶液, 另两组注射等量生理盐水24周。所有大鼠在IS注射结束1周时采集血液标本, 测量肌酐及IS浓度, 采集心超图像后处死, 采集心脏标本, 血液IS浓度测量采用高效液相色谱-电喷雾电离-串联质谱(HPLC-ESI-MS/MS)法[11]。

超声心动图像采集  所有大鼠均于基线状态下及IS注射结束1周时采集常规二维及斑点追踪显像图像, 采用GE E9超声诊断仪, 12S探头, 采集时频率设为11 MHz, 深度为2.5 cm, 帧频为(220±25)F/s。图像定量分析采用EchoPAC BT12脱机软件。

二维超声图像定量分析  在大鼠左室胸骨旁长轴切面, 将取样线尽量垂直穿过室间隔及二尖瓣前叶瓣尖, 取M型, 测量左室舒张末内径(left ventricular end-diastolic diameter, LVEDD)及收缩末内径(left ventricular end-systolic diameter, LVESD), 计算左室射血分数(left ventricular ejection fraction, LVEF)。于左室乳头肌水平短轴根据时钟法分为4个象限, 于每个象限内分别测量左室壁厚度且取平均值为左室壁厚度(left ventricular wall thickness, LVWT)。

斑点追踪图像分析  采用大鼠左室乳头肌水平短轴图像, 进入斑点追踪分析2D分析系统, 手动描绘心内膜, 调整追踪环宽度, 软件自动识别并跟踪整个心动周期内的左室壁声学斑点, 自动计算出左室应变及应变率指标(图 1):环向应变(circumferential strain, CS)、径向应变(radial strain, RS)、径向应变率(RS rate, SRr)和环向应变率(CS rate, SRc), 径向应变率舒张早期E’峰(E’-SRr)和径向应变率舒张晚期A’峰(A’-SRr), 环向应变率舒张早期E’峰(E’-SRc)和环向应变率舒张晚期A’峰(A’-SRc), 并计算左室舒张功能参数径向E’/A’-SRr和环向E’/A’-SRc[12]。每个图像分别分析3个心动周期并取平均值。

CS:Circumferential strain; RS:Radial strain; RSr:RS rate; STI:speckle tracking imaging. 图 1 STI测量左室CS (A)、RS (B)及RSr (C) Fig 1 CS (A), RS (B) and RSr (C) of left ventricle by STI
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病理学检查  图像采集结束后处死大鼠, 取心脏, 称重, 观察心肌大体形态。HE染色, 光镜下观察心肌细胞形态(细胞核、胞质、横纹), 细胞核呈蓝色, 细胞质呈淡红色, 评价心肌细胞肥厚及坏死程度。在200倍镜下摄片, 测量镜下细胞总面积及细胞数, 计算单个细胞面积平均值。Masson染色, 观察心肌细胞纤维化程度, 心脏组织中胶原纤维呈蓝色。病理切片评分由1名经验丰富且不知情的病理科医师完成。

一致性检验  对10例随机选取的大鼠图像使用斑点追踪显像分析的测量结果进行一致性检验。观察者内差异为同一观察者间隔24 h以上的2次测量结果比较, 观察者间差异为2位独立观察者各自的测量结果比较, 采用组内相关系数(intra-class correlation coefficient, ICC)表示。

统计学方法  计量资料采用x±s表示, 采用General Linear Model中的Repeated Measures分析基线和实验完成时以及各组之间的超声数据比较。一致性检验采用ICC表示。以双侧P < 0.05为差异有统计学意义。统计分析软件为SPSS 16.0。

结果

实验室数据  IS组中3只大鼠在注射IS后12~20周猝死, 未采集实验后的超声图像, 故未纳入最终统计分析。经解剖发现, 这3只大鼠中2只存在大量心包和腹腔积液, 1只在注射部位出现巨大坏死包块。3组大鼠基线、建模成功及实验结束时的血肌酐数值及血IS值见表 1。

表 1 3组大鼠基线、建模成功和实验结束时的血肌酐值及血IS值 Tab 1 Serum creatinine and IS on baseline, successful modeling and post-operation in the 3 groups of rats (x±s)
StateSOR group (n=10)CRF group (n=10)IS group (n=7)
Scr (μmol/L)IS (μg/mL)Scr (μmol/L)IS (μg/mL)Scr (μmol/L)IS (μg/mL)
Baseline58.1±4.60.9±0.253.8±6.50.9±0.458.9±7.90.9±0.6
Successful modeling61.8±5.51.0±0.2163.8±10.0(1)(2)4.7±1.0(1)(2)167.4±12.3(1)(2)4.6±1.1(1)(2)
Post-operation60.6±6.70.9±0.3170.2±21.6(1)(2)4.5±0.9(1)(2)258.6±37.8(1)(2)(3)20.1±2.6(1)(2)(3)
(1) vs.Baseline, (2)vs. SOR group, (3)vs. CRF group, P < 0.05.Scr:Serum creatinine; IS:Indoxyl sulfate.
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常规超声心动图数据比较  基线状态下3组参数差异无统计学意义。3组LVEDD较基线均明显增大; SOR组室壁厚度与基线差异无统计学意义, 而另两组室壁厚度较基线均明显增厚(P均 < 0.05);SOR组LVEF由92%±3%降至88%±5%(P < 0.001), 而另两组LVEF术后与基线无明显改变(图 2和表 2~3)。

A:SOR group; B:CRF group; C:IS group. 图 2 大鼠术后左室乳头肌水平短轴图像 Fig 2 Images of short axis of left ventricle after operations in rats
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表 2 3组大鼠基线与实验后心超数据比较 Tab 2 Comparison of echocardiographic parameters on baseline and post-operation in the 3 groups of rats (x±s)
ParametersSOR group (n=10)CRF group (n=10)IS group (n=7)
BaselinePost-
operation		PBaselinePost-
operation		PBaselinePost-
operation		P
HR (bpm)217±22201±210.005218±19227±370.368221±20240±350.126
LVEDD (mm)5.86±0.517.08±0.58< 0.0015.68±0.527.01±0.72< 0.0015.82±0.456.73±0.620.012
LVWT (mm)1.64±0.101.70±0.080.4311.68±0.042.22±0.26< 0.0011.61±0.132.94±0.31< 0.001
LVEF (%)91±586±50.02190±491±40.45191±594±40.387
RS (%)24.1±9.223.8±9.60.13524.3±11.137.4±17.8< 0.00127.6±10.331.5±15.10.265
CS (%)-10.9±3.5-10.5±4.50.103-10.9±3.8-13.5±4.60.002-12.1±4.2-13.2±3.40.432
SRr (s-1)4.8±1.18.4±1.7< 0.0014.5±0.89.7±2.1< 0.0014.7±0.79.7±1.8< 0.001
SRc (s-1)-3.5±0.3-3.6±0.50.389-3.4±0.4-5.1±1.2< 0.001-3.5±0.4-5.4±0.8< 0.001
E’/A’-SRr0.9±0.20.9±0.30.4210.9±0.20.4±0.1< 0.0010.9±0.30.2±0.1< 0.001
E’/A’-SRc0.9±0.20.9±0.20.5630.9±0.30.4±0.1< 0.0010.9±0.20.2±0.1< 0.001
HR:Heart rate; LVEDD:Left ventricular end-diastolic diameter; LVWT:Left ventricular wall thickness; LVEF:Left ventricular ejection fraction; RS:Radial strain; CS:Circumferential strain; SRr:RS rate; SRc:CS rate.
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表 3 3组大鼠实验后心超数据的组间比较 Tab 3 Pairwise comparison of echocardiographic parameters on post-operation in the 3 groups of rats (P value)
ParametersCRF vs.SORIS vs.SORIS vs.CRF
HR (bpm)0.0850.0060.841
LVEDD (mm)0.8470.1670.236
LVWT (mm)0.001< 0.0010.002
LVEF (%)0.1070.0920.584
RS (%)0.0010.0670.107
CS (%)0.0090.0340.724
SRr (s-1)0.0750.1020.862
SRc (s-1)< 0.001< 0.0010.357
E’/A’-SRr< 0.001< 0.0010.007
E’/A’-SRc< 0.001< 0.0010.006
Abbreviations refer to Tab 2.
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应变参数比较  基线状态下3组CS及RS差异无统计学意义。实验前后比较, RS在CRF组中显著增加(P=0.017), RS及CS在IS组及SOR组差异均无统计学意义(表 3)。

应变率参数比较  基线状态下比较3组SRr、SRc、E’/A’-SRr及E’/A’-SRc, 差异均无统计学意义。CRF组和IS组实验后SRc及SRr较基线均明显增加(P < 0.001); 而SOR组实验前后SRc无显著变化, 实验后SRr较基线明显增加(P=0.001)。实验后3组SRc及SRr比较差异无统计学意义。IS组和CRF组实验后E’/A’-SRc和E’/A’-SRr较基线均显著降低(P均 < 0.001), SOR组则无显著变化。实验后IS组E’/A’-SRc和E’/A’-SRr均显著低于CRF组(P=0.01和0.001, 表 3)。

一致性检验  STI指标RS、CS、SRr、SRc、E’/A’-SRr和E’/A’-SRc的观察者内差异的ICC值分别为0.93(95%CI:0.79~0.98, P < 0.001)、0.91(95%CI:0.76~0.95, P < 0.001)、0.92(95%CI:0.80~0.96, P < 0.001)、0.91(95%CI:0.73~0.97, P < 0.001)、0.88(95%CI:0.70~0.93, P=0.001)和0.89(95%CI:0.71~0.94, P=0.001), 观察者间差异的ICC值分别为0.90(95%CI:0.75~0.95, P < 0.001)、0.89(95%CI:0.73~0.94, P < 0.001)、0.89(95%CI:0.73~0.93, P < 0.001)、0.88(95%CI:0.72~0.93, P < 0.001)、0.83(95%CI:0.70~0.92, P=0.001)和0.85(95%CI:0.73~0.94, P=0.001)。提示STI测量获得的应变及应变率参数一致性较好。

病理学检查  CRF组及IS组的心脏重量均大于SOR组(P < 0.05)。HE染色示:SOR组、CRF组及IS组心肌细胞面积依次增大(P < 0.05);Masson染色示:3组心肌纤维化程度依次增加(图 3, 表 4)。

A:SOR group; B:CRF group; C:IS group.A1, B1 and C1:HE staining; A2, B2 and C2:Masson staining (blue area indicated fibrosis). 图 3 大鼠心脏的病理学检查(×200) Fig 3 Pathologial examination of rats' cardiac tissues (×200)
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表 4 3组大鼠心脏重量及心肌细胞面积的比较 Tab 4 Histological analysis of heart weight and myocardial cell area in the 3 groups of rats (x±s)
ParametersSOR group
(n=10)		CRF group
(n=10)		IS group
(n=7)		P (1)P (2)P (3)
Heart weight (g)/100 g body weight0.47±0.040.53±0.030.58±0.050.0230.0070.106
Area of myocardial cell (μm2)496±14568±12739±110.0030.001< 0.001
(1)CRF vs.SOR; (2)IS vs.SOR; (3)IS vs.CRF.
表选项
讨论

IS分子式为C8H7NO4S, 相对分子质量为213 210, 为阴离子蛋白结合尿毒症毒素, 是肠道细菌酵解蛋白质的产物。肠道细菌分解色氨酸产生吲哚, 经门静脉入肝, 经羟化生成3-羟基吲哚, 再经硫酸化生成IS。循环中90%以上的IS和白蛋白非共价结合, 正常情况下IS通过近端肾小管分泌由尿液排出体外, 肾功能受损时在体内蓄积[13]。近年来IS在ESRD患者心血管并发症中的作用越来越受到重视, 研究发现:IS是预测ESRD患者并发心血管疾病的重要标志物[14]; 血浆IS高浓度是全因死亡和心血管疾病死亡的强力预测因子[15]; 258例维持性血液透析患者中, 血浆IS高浓度组较低浓度组的心衰发生风险增加5.31倍[16]。基础研究证实, IS可通过多种途径参与动脉粥样硬化的发生[17-18], 同时通过诱导氧化应激[6]、激活p38 MAPK、p42/44 MAPK和NF-κB[19]、抑制肾脏Klotho基因表达[20]等多条通路促进心肌细胞肥厚和胶原纤维增生; 动物实验证实, 口服碳吸附剂AST-120可通过抑制IS前体的吸收, 显著降低肾功能不全大鼠的心肌纤维化和改善预后[21]。

目前缺乏IS在体研究资料, 更鲜有运用超声心动图评估的报道。本研究采用常规超声测量, 发现CRF组和IS组左室心肌明显肥厚, 且IS组心肌肥厚更显著, 与心脏大体重量和病理结果一致, 证实超声心动图在评估左心室壁肥厚方面的可行性和准确性。反之, LVEF在CRF组和IS组均未显著受损, 甚至出现代偿性增强, 可能与本实验采用Teichholtz校正公式计算LVEF有关, Teichholtz公式侧重于径向收缩的成分, 而心肌肥厚的功能变化早期常表现为纵向收缩降低而径向收缩代偿性增强[22]。该结果从侧面证实了采用常规超声参数LVEF评估心脏受损的局限性和滞后性。

STI技术基于高帧频灰阶超声图像, 实时跟踪心肌内回声斑点的空间运动, 具有较高的时间及空间分辨率, 无角度依赖性, 能分辨心肌的主动运动和被动牵拉, 多项研究证实其能敏感准确发现心肌的结构功能改变, 且与磁共振结果高度相关[23]。本研究采用STI显示RS在CRF组中显著增加, CS也有增加的趋势, 而IS组前后并无显著变化, 提示IS组的心肌代偿能力下降。Kouzu等[24]在高血压人群中发现其纵向应变较正常人降低, 但其早期RS较正常人增强, 尿毒症性心肌改变发生纵向应变的降低是多个研究获得的共识, 而对于RS及CS是否发生改变仍有争议, 由于大鼠心脏的超声切面非常有限, 无法获得满意的心尖部四腔心等切面, 故未能成功分析长轴应变数据, 这也是本实验的局限性之一。

啮齿类动物作为研究对象, 由于心率快, 超声切面有限, 左心室舒张功能评估一直是个难点, 而STI的应变率显像则为评价左心室的舒张功能开辟了一条全新的道路。文献报道采用应变率显像评价左室舒张功能更为敏感可靠[12]。舒张功能反映心肌细胞的顺应能力, 心肌细胞肥厚、坏死及纤维化均可导致心肌的顺应性下降而产生舒张功能障碍, 而舒张功能障碍可通过心室的充盈不良进一步影响左心室的收缩功能[25]。肾功能不全患者中舒张功能障碍发生率达50%~65%, 且其发生早于收缩功能障碍[26], 与不良预后密切相关[27]。Sato等[28]报道高血浆IS与左室舒张功能障碍密切相关, 这可能与IS刺激心肌细胞肥大、加重纤维化有关。本研究采用STI技术获得左心室舒张功能参数, 通过比较显示CRF组和IS组的左心室舒张功能出现显著减退, 且IS组减退程度更为显著, 证实了STI在动物实验中评价左心室舒张功能的可行性与准确性。

啮齿类动物的心率较快, 对图像的帧频要求较高, 常规二维超声无法兼顾帧频和清晰度, 导致资料无法分析。STI帧频较高, 在本研究中可达到220~250帧/s, 具备较高的时间分辨率[29], 是啮齿类动物实验中心脏超声评估的首选。

本研究的不足之处:(1)未设立单纯注射IS组, 在肾功能正常人群中IS的清除率为(3 023±533) mL·min-1·1.73 m-2, 是肌酐的(22±4)倍[30], 故未设立单纯注射IS大鼠组作为对照; (2)未能成功分析获得纵向应变资料; (3) IS组中有3例大鼠在IS注射期间猝死, 并出现心包、胸腔积液和局部脓肿包块, 可能与IS注射部位消毒操作不规范及IS对局部组织的刺激作用有关, 应规范操作以避免类似情况的发生; (4)动物样本量较小, 未通过IS注射量进行分组研究, 未能进一步分析IS导致的心肌细胞病变是否具有剂量相关性, 这将成为下一步的研究方向。

IS可以加重肾功能不全大鼠的心肌损害, 表现为心肌细胞的肥厚、坏死和纤维化, 且左室舒张功能的下降早于收缩功能受损, 应变率显像的舒张功能指标可敏感检测IS导致的左室舒张功能改变。

参考文献
[1]
COLLINS AJ, FOLEY RN, CHAVERS B, et al. US renal data system 2011 annual data report[J]. Am J Kidney Dis, 2012, 59(1): e420. [URI]
[2]
LIABEUF S, DRUEKE TB, MASSY ZA. Protein-bound uremic toxins:new insight from clinical studies[J]. Toxins (Basel), 2011, 3(7): 911-919. [DOI]
[3]
LIN CY, HSU SC, LEE HS, et al. Enhanced expression of glucose transporter-1 in vascular smooth muscle cells via the Akt/tuberous sclerosis complex subunit 2(TSC2)/mammalian target of rapamycin (mTOR)/ribosomal S6 protein kinase (S6K) pathway in experimental renal failure[J]. J Vasc Surg, 2013, 57(2): 475-485. [DOI]
[4]
SHIMIZU H, HIROSE Y, GOTO S, et al. Indoxyl sulfate enhances angiotensin Ⅱ signaling through upregulation of epidermal growth factor receptor expression in vascular smooth muscle cells[J]. Life Sci, 2012, 91(5-6): 172-177. [DOI]
[5]
LIU S, WANG BH, KOMPA AR, et al. Antagonists of organic anion transporters 1 and 3 ameliorate adverse cardiac remodelling induced by uremic toxin indoxyl sulfate[J]. Int J Cardiol, 2012, 158(3): 457-458. [DOI]
[6]
YISIREYILI M, SHIMIZU H, SAITO S, et al. Indoxyl sulfate promotes cardiac fibrosis with enhanced oxidative stress in hypertensive rats[J]. Life Sci, 2013, 92(24-26): 1180-1185. [DOI]
[7]
AMUNDSEN BH, HELLE-VALLE T, EDVARDSEN T, et al. Noninvasive myocardial strain measurement by speckle tracking echocardiography:validation against sonomicrometry and tagged magnetic resonance imaging[J]. J Am Coll Cardiol, 2006, 47(4): 789-793. [DOI]
[8]
孟庆国, 尹立雪, 李春梅, 等. 超声斑点成像技术评价左心室长轴心肌节段应变与位移[J]. 中华超声影像学杂志, 2006, 15(10): 721-724. [DOI]
[9]
薛继平, 王健, 康春松. 慢性肾功能衰竭动物模型制作的研究[J]. 实用医技杂志, 2009(12): 953-955. [DOI]
[10]
ADIJIANG A, GOTO S, URAMOTO S, et al. Indoxyl sulphate promotes aortic calcification with expression of osteoblast-specific proteins in hypertensive rats[J]. Nephrol Dial Transplant, 2008, 23(6): 1892-1901. [DOI]
[11]
CHEN J, ZHANG X, ZHANG H, et al. Indoxyl sulfate enhance the hypermethylation of klotho and promote the process of vascular calcification in chronic kidney disease[J]. Int J Biol Sci, 2016, 12(10): 1236-1246. [DOI]
[12]
WANG J, KHOURY DS, THOHAN V, et al. Global diastolic strain rate for the assessment of left ventricular relaxation and filling pressures[J]. Circulation, 2007, 115(11): 1376-1383. [DOI]
[13]
TAN X, CAO X, ZOU J, et al. Indoxyl sulfate, a valuable biomarker in chronic kidney disease and dialysis[J]. Hemodial Int, 2017, 21(2): 161-167. [URI]
[14]
LIN CJ, LIU HL, PAN CF, et al. Indoxyl sulfate predicts cardiovascular disease and renal function deterioration in advanced chronic kidney disease[J]. Arch Med Res, 2012, 43(6): 451-456. [DOI]
[15]
BARRETO FC, BARRETO DV, LIABEUF S, et al. Serum indoxyl sulfate is associated with vascular disease and mortality in chronic kidney disease patients[J]. Clin J Am Soc Nephrol, 2009, 4(10): 1551-1558. [DOI]
[16]
CAO XS, CHEN J, ZOU J, et al. Association of indoxyl sulfate with heart failure among patients on hemodialysis[J]. Clin J Am Soc Nephrol, 2015, 10(1): 111-119. [DOI]
[17]
HUNG SC, KUO KL, HUANG HL, et al. Indoxyl sulfate suppresses endothelial progenitor cell-mediated neovascularization[J]. Kidney Int, 2016, 89(3): 574-585. [DOI]
[18]
HSU CC, LU YC, CHIU CA, et al. Levels of indoxyl sulfate are associated with severity of coronary atherosclerosis[J]. Clin Invest Med, 2013, 36(1): E42-E49. [DOI]
[19]
LEKAWANVIJIT S, ADRAHTAS A, KELLY DJ, et al. Does indoxyl sulfate, a uraemic toxin, have direct effects on cardiac fibroblasts and myocytes?[J]. Eur Heart J, 2010, 31(14): 1771-1779. [DOI]
[20]
YANG K, WANG C, NIE L, et al. Klotho protects against indoxyl sulphate-induced myocardial hypertrophy[J]. J Am Soc Nephrol, 2015, 26(10): 2434-2446. [DOI]
[21]
TAN X, HE J, CAO X, et al. Effects of oral carbonic adsorbent (AST-120) on kidney of early-stage chronic kidney disease rats[J]. Ren Fail, 2015, 37(2): 337-342. [DOI]
[22]
雷常慧.三维斑点追踪技术评价肥厚型心肌病早期左心室收缩功能[D].宁夏医科大学, 2015. [URI]
[23]
ROES SD, MOLLEMA SA, LAMB HJ, et al. Validation of echocardiographic two-dimensional speckle tracking longitudinal strain imaging for viability assessment in patients with chronic ischemic left ventricular dysfunction and comparison with contrast-enhanced magnetic resonance imaging[J]. Am J Cardiol, 2009, 104(3): 312-317. [DOI]
[24]
KOUZU H, YUDA S, MURANAKA A, et al. Left ventricular hypertrophy causes different changes in longitudinal, radial, and circumferential mechanics in patients with hypertension:a two-dimensional speckle tracking study[J]. J Am Soc Echocardiogr, 2011, 24(2): 192-199. [DOI]
[25]
ZILE MR, BAICU CF, GAASCH WH. Diastolic heart failure--abnormalities in active relaxation and passive stiffness of the left ventricle[J]. N Engl J Med, 2004, 350(19): 1953-1959. [DOI]
[26]
AHMED A, RICH MW, SANDERS PW, et al. Chronic kidney disease associated mortality in diastolic versus systolic heart failure:a propensity matched study[J]. Am J Cardiol, 2007, 99(3): 393-398. [DOI]
[27]
IWABUCHI Y, OGAWA T, INOUE T, et al. Elevated E/E' predicts cardiovascular events in hemodialysis patients with preserved systolic function[J]. Intern Med, 2012, 51(2): 155-160. [DOI]
[28]
SATO B, YOSHIKAWA D, ISHII H, et al. Relation of plasma indoxyl sulfate levels and estimated glomerular filtration rate to left ventricular diastolic dysfunction[J]. Am J Cardiol, 2013, 111(5): 712-716. [DOI]
[29]
DANDEDL M, HETZER R. Echocardiographic strain and strain rate imaging--clinical applications[J]. Int J Cardiol, 2009, 132(1): 11-24. [URI]
[30]
SIRICH TL, ARONOV PA, PLUMMER NS, et al. Numerous protein-bound solutes are cleared by the kidney with high efficiency[J]. Kidney Int, 2013, 84(3): 585-590. [DOI]

文章信息

孙敏敏, 曹学森, 潘翠珍, 郭瑶, 谭笑, 舒先红
SUN Min-min, CAO Xue-sen, PAN Cui-zhen, GUO Yao, TAN Xiao, SHU Xian-hong
二维斑点追踪显像(STI)评价硫酸吲哚酚(IS)对肾功能不全(CRF)大鼠的心脏毒性
Assessment of indoxyl sulfate (IS)-induced cardiotoxicity in rats with chronic renal failure (CRF) by speckle tracking imaging (STI)
复旦学报医学版, 2019, 46(6): 726-732.
Fudan University Journal of Medical Sciences, 2019, 46(6): 726-732.
Corresponding author
SHU Xian-hong, E-mail:shu.xianhong@zs-hospital.sh.cn.
基金项目
上海市卫计委科研课题青年基金项目（20174Y0054）；上海市自然科学基金面上项目（19ZR1450900）
Foundation item
This work was supported by the Youth Foundation of Shanghai Municipal Commission of Health and Family Planning (20174Y0054) and the General Program of Shanghai Natural Science Foundation (19ZR1450900)

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