重组血管紧张素转换酶2对高血压小鼠肾脏Nephrin信号及结构损伤的影响  

Effects of recombinant angiotensin-converting enzyme 2on renal Nephrin signaling and structural injury in hypertensive mice

作　　者：陈来江 徐颖乐[1] 金海燕[1,2] 徐冉[1] 张振洲[1] 宋蓓[1] 高平进[1] 钟久昌[1] 

机构地区：[1]上海交通大学医学院附属瑞金医院医学基因组学国家重点实验室、上海市高血压研究所 [2]上海交通大学医学院附属瑞金医院临床心理科,上海200025

出　　处：《中华高血压杂志》2015年第10期952-957,共6页Chinese Journal of Hypertension

基　　金：国家重大研究计划资助项目(91339108);国家自然科学基金项目(81170246;81370362);国家重点基础研究发展计划(2014CB542300);上海市卫生局科研课题(201440368)

摘　　要：目的 探讨高血压状态下肾脏组织足细胞蛋白Nephrin信号改变以及重组血管紧张素转换酶2（ACE2）干预治疗对该信号和肾脏超微结构改变的影响。方法 采用10~11周龄C57/B6小鼠,随机分成3组：正常对照组（n=8）;高血压＋安慰剂组（n=6）;高血压＋重组ACE2干预组（n=6）。高血压＋安慰剂组和高血压＋重组ACE2干预组小鼠每天经微泵给予1.5mg/kg血管紧张素Ⅱ（AngⅡ）制备高血压模型,然后每天分别经腹腔注射给予安慰剂或重组ACE2 2mg/kg治疗,为期2周。用尾套法测定小鼠血压水平。采用Western-blot及硫代巴比妥酸比色法检测小鼠肾脏组织中Nephrin表达和丙二醛含量。用透射电镜技术观测小鼠肾脏超微结构改变。结果 与正常对照组相比,高血压＋安慰剂组小鼠血压水平明显升高[（156.2±9.8）比（100.8±9.9）mm Hg,P〈0.01],肾脏组织中Nephrin蛋白表达下调,丙二醛含量增加[Nephrin相对表达：0.48±0.06比1.00±0.08;丙二醛（159.6±12.1）比（55.2±9.0）nmol/g,均P〈0.01],与高血压＋安慰剂组相比,高血压＋重组ACE2组小鼠血压明显下降[（134.8±8.3）比（156.2±9.8）mm Hg,P〈0.05],肾脏组织Nephrin表达增加,丙二醛含量下降[Nephrin：0.71±0.07比0.48±0.06;丙二醛：（98.5±11.5）比（159.6±12.1）nmol/g,均P〈0.05]。另外,重组ACE2干预明显改善高血压小鼠肾脏功能,并减轻肾脏超微结构损伤,表现为肾小管空泡线粒体结构减少,肾小球基底膜增厚与足突细胞融合现象得到改善。结论 高血压状态下存在肾脏组织中Nephrin信号下调,伴有氧化应激增强和结构损伤明显,而重组ACE2治疗通过改善高血压小鼠肾脏Nephrin表达水平,可促使肾脏氧化应激水平降低与结构损伤减轻,提示ACE2对高血压具有一定的肾脏保护功效。Objective To investigate the alteration of renal podocyte Nephrin signaling and ultrastructural injury in hypertension state and the effects of recombinant human angiotensin-converting enzyme 2 （rhACE2） on these altera- tions. Methods The 10- or 11-week C57/B6 mice were randomized to three groups, including the normal control group （n= 8 ）, the hypertension＋ placebo group （n = 6 ） and the hypertension＋ rhACE2 treatment group （ n = 6 ）. Hypertensive model was established by infusion of angiotensin Ⅱ （Ang Ⅱ ） daily with the dose of 1.5 mg/kg, and the hypertensive mice were then treated with rhACE2 （2 mg/kg per day, intraperitoneal） or placebo for 2 weeks. The systolic blood pressure （SBP） of mice was measured by the tail-cuff method. Nephrin protein and malonyldial- dehyde （MDA） concentrations in mouse kidneys were determined with Western blot and thiobarbituric acid （TBA） reactive substances methods, respectively. In addition, renal ultrastructure was observed via transmission electron microscope. Results Compared with control group, SBP levels were obviously elevated in the AngⅡ-induced hy- pertensive mice [（156.2±9.8） vs （100.8±9.9）mm Hg, P〈0.01], associated with reduced Nephrin protein levelsand enhanced MDA content [Nephrin：0.48±0.06 vs 1.00±0.08 and MDA （159.6±12.1） vs （55.2±9.0）nmol/g, P〈0.01, respectively]. Compared with hypertension＋ placebo group, treatment with rhACE2 significantly de- creased SBP levels [（134.8±8.3） vs （156.2±9.8） mm Hg, P〈0.05], and promoted renal Nephrin levels in hy- pertensive mice, along with a marked reduction in MDA contents [Nephrin： 0.71±0.07 vs 0.48±0.06 and MDA （98.5±11.5） vs （159.6±12.1） nmol/g, P〈0.05, respectively]. Finally, treatment with rhACE2 strikingly at- tenuated renal uhrastructure injury in hypertensive mice, characterized with the decrease of vacuolizated mitochondria in renal tubular, and improvement of the thickening glomerular capillary basement membrane and

关 键 词：高血压 血管紧张素转换酶2 氧化应激 NEPHRIN 肾脏保护 

分 类 号：R544.1[医药卫生—心血管疾病]