【目的】研究脾胃虚损型重症肌无力(myasthenia gravis,MG)患者与正常人骨骼肌蛋白的差异性表达情况,以探讨MG的发病机制。【方法】采用双向电泳技术对脾胃虚损型MG患者与正常人的骨骼肌蛋白进行分离,采用Image Master 2D platinum 5.0软件对所得的图像进行分析,寻找差异性蛋白。对比值≥1.5的差异蛋白点运用基质辅助激光解吸电离—飞行时间质谱法进行鉴定,在IPI数据库进行搜索,寻找匹配的相关蛋白质。【结果】通过双向电泳技术分析,在实验组脾胃虚损型MG患者与正常对照组骨骼肌中共找到27个表达差异的蛋白质斑点,其中实验组呈低表达,对照组呈高表达的有14个蛋白质点;实验组呈高表达,对照组呈低表达的有13个蛋白质点。对27个表达差异的蛋白质点中选择比值较大的15个蛋白质点进行质谱鉴定,共鉴定出10个蛋白。【结论】MG的发病和(或)病理过程可能是多种机制参与的结果,与骨骼肌收缩有关的肌细胞结构蛋白表达变化、线粒体能量代谢障碍、钙通道以及氧自由基等均可能与此相关,MG与纤维蛋白原及其肽链,MG并发胸腺增生或胸腺瘤与ADP-Ribosylarginine Hydrolase是否存在关系,尚不明确。
Objective To study the differences of skeletal muscle protein expression between myasthenia gravis (MG) patients of spleen and stomach deficiency type and the normal volunteers, and to explore the pathogenesis of MG. Methods We applied the two-dimensional electrophoresis (2-DE) technology to separate the skeletal muscle protein of spleen and stomach deficiency MG patients and the normal, and used Image Master 2D platinum 5.0 software to analyze the obtained images. And then the differential proteins with the relative ratio being or over 1.5 were identified by using matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS) . Finally, the matched proteins were obtained after searching in the IPI database. Results By means of 2-DE technology, 27 protein spots which expressed differently were found in MG patients of spleen and stomach deficiency type and the normal. Of the 27 protein spots, 14 had low expression in the experimental group and high expression in the normal control group, and 13 had high expression in the experimental group and low expression in the normal control group. Among 27 differential proteins, 10 proteins have been identified from the 15 proteins with higher relative ratio. Conclusion The pathogenesis and (or) pathological process of MG would probably be the results of a variety of mechanisms involved, such as the changes of muscle cell structural protein expression, the disorder of mitochondrial energy metabolism, as well as calcium channel and oxygen free radicals associated with skeletal muscle contraction. However, it still remains uncertain that MG is related with fibrinogen and its peptide chain, or the complications of thymie hyperplasia and thymic tumor in MG are correlated with ADP-ibosylarginine hydrolase.