MALDI-TOF-MS对DAI大鼠脑干蛋白质组学的分析

Proteomic Analysis of Rat Brain Stem with DAI by MALDI-TOF-MS

目的应用基质辅助激光解吸/电离-飞行时间质谱(matrix-assisted laser desorption/ionization timeof-flight mass spectrometry,MALDI-TOF-MS)技术建立弥漫性轴索损伤(diffuse axonal injury,DAI)诊断模型,筛选DAI相关蛋白或多肽,为寻找DAI的分子标志物提供理论基础。方法将15只雄性SD大鼠随机分为DAI组(n=10)和对照组(n=5),采用MALDI-TOF-MS技术对两组大鼠脑干组织的蛋白或多肽表达谱进行检测,运用Clin Pro Tools 2.2分析软件筛选出具有差异的分子峰,应用遗传算法建立诊断模型。结果筛选出有差异的分子峰61个(P<0.05),其中DAI组有9个分子峰下调,52个分子峰上调。筛选出5个分子峰建立诊断模型,交叉验证的特异性为96.14%、敏感性为95.98%,盲法验证结果的特异性为73.33%、敏感性为70.00%。结论应用MALDI-TOF-MS技术不仅能够建立特异性和敏感性较高的DAI诊断模型,还可以筛选差异蛋白或多肽,为DAI的法医学鉴定奠定理论基础。

Objective To establish a diagnostic model for diffuse axonal injury （DAI） by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS）. To screen the proteins or peptides associated with DAI for providing the biomarkers with theoretic foundation. Methods Fifteen male Sprague-Dawley rats were randomly divided into DAI group （n=10） and control group （n=5）. The protein or peptide expression profiles of rat brain stem were detected by MALDI-TOF-MS. ClinProTools 2.2 software was used to find specific peaks, and a diagnostic model was established by the genetic al- gorithm. Results There were significant differences in 61 peaks of DAI group （P〈0.05）, 9 peaks were down-regulated and 52 up-regulated. The diagnostic model was established based on 5 different peaks. The specificity and sensitivity of cross validation was 96.14% and 95.98%; while the specificity and sen- sitivity of blind validation showed was 73.33% and 70.00%, respectively. Conclusion A specific and sen- sitive diagnostic model of DAI can be established by MALDI-TOF-MS to provide a potential value for determining DAI in forensic practice.