尿液细胞呼吸链酶在MELAS综合征中的表达及意义  

Expression and significance of respiratory chain enzyme of cells in urine sediment in MELAS syndrome

作　　者：吴海荣[1] 马祎楠[2] 戚豫[2] 刘红刚[1] 

机构地区：[1]首都医科大学附属北京同仁医院病理科,100730 [2]北京大学第一医院中心实验室

出　　处：《中华医学杂志》2013年第16期1247-1250,共4页National Medical Journal of China

摘　　要：目的探讨尿液细胞中呼吸链酶在线粒体脑肌病伴高乳酸血症和卒中样发作（MELAS）综合征中的表达及意义。方法采用酶组织化学染色法标记20例A3243G突变的MELAS患者（MELAS组）及其配对20名健康人（对照组）尿液细胞的呼吸链酶，了解MELAS组呼吸链酶的改变情况；同时应用免疫组化的方法检测复合物Ⅳ中核基因组及线粒体基因组编码蛋白对其表达的影响。应用ImageproPlus6．0软件分析染色图片的吸光度（A）值作为染色强度，数据以M（Q1，Q3）表示，并进行统计学分析。结果MELAS组呼吸链酶复合物I染色强度低于对照组[0．06（0．01，0．12）比0．12（0．01，0．62），P=0．010]；复合物Ⅱ的SDH染色强度MELAS组和对照组差别不大，但光镜下观察发现MELAS组有13例（65％）出现细胞质中蓝色颗粒密度增加的线粒体聚集现象；复合物Ⅳ的染色强度低于对照组[0．14（0．03，0．32）比0．23（0．06，0．43），P=0．038]。复合物Ⅳ核基因组编码细胞色素C氧化酶（COX）4蛋白（A21347抗体）表达水平低于对照组[0．05（0．02，0．45）比0．17（0．03，0．70），P=0．000]；线粒体基因组编码MTC02蛋白（A6404抗体）表达水平低于对照组[0．03（0．01，0．07）比0．15（0．09，0．23），P=0．000]。结论A3243G突变MELAS患者尿液细胞存在呼吸链酶的异常改变及复合物Ⅳ两种DNA编码蛋白的低表达，这可能对线粒体脑肌病的诊断、分型及机制研究有重要价值。Objective To explore the expression and significance of respiratory chain enzyme of cells in urine sediment in mitochondrial encephalopathy myopathy, lactic acidosis and stroke-like episodes （MELAS） syndrome. Methods Through enzyme histochemistry, the authors analyzed the changes of respiratory chain enzyme in urine sediment in 20 MELAS patients due to mitochondrial A3243G mutation （MELAS group） and 20 health peoples （control group）. And the impact on the expression of protein encoded by nuclear DNA （A21347） and mitochondrial DNA （A6404） was detected by immunoehemistry. Image pro Plus 6.0 software was used for analysis of absorbance （A） of staining images as staining intensity. The data were expressed as M （ Q1, Q3 ） and analyzed through statistical software. Results The staining intensity of complexes I in the MELAS group was lower than that in the control group （0. 06（0.01, 0. 12） vs 0. 12（0. 01, 0. 62）, P = 0. 010）. The intergroup staining intensity of complex II showed no marked difference. Increased density of blue particle and cytoplasmic gathering was found in 13 cased （65%） of the MELAS group under light microscope. The staining intensity of complexes 1V was expressed at a low level in the MELAS group （0. 14 （0.03, 0. 32 ） vs 0. 23 （0. 06, 0.43 ）, P = 0. 038 ）. The expression of protein encoded by nuclear DNA （A21347） was lower than that in the control group （0.05 （0. 02, 0. 45 ） vs 0. 17 （0. 03, 0. 70）, P = 0. 000）. The expression of protein encoded by mitochondrial DNA （A6404） was also lower than that in the control group （0. 03（0.01,0.07） vs 0. 15 （0. 09, 0. 23）, P =0. 000）. Conclusion Abnormal change of respiratory chain enzyme in urine sediment in MELAS due to mitochondrial A3243G mutation and a low expression of proteins encoded by two kinds of DNA in complexes IV can help to confirm the genetic diagnosis of mitochondrial encephalomyopathies so that different subtypes may be classified and its pathogenesis elucid

关 键 词：MELAS综合征 线粒体脑肌病 呼吸链酶 尿 

分 类 号：R746[医药卫生—神经病学与精神病学]