基于空气动力辅助离子化-超高分辨质谱成像技术的大鼠肾脏组织中多种类代谢物的分布研究  

Study on Tissue Distribution of A Variety of Endogenous Metabolites by Air Flow Assisted Ionization-Ultra High Resolution Mass Spectrometry Imaging

作　　者：王中华[1] 何秉淑 孙成龙 宋肖炜 贺玖明 张瑞萍 再帕尔·阿不力孜[1,2] WANG Zhong-Hua;HE Bing-Shu;SUN Cheng-Long;SONG Xiao-Wei;HE Jiu-Ming;ZHANG Rui-Ping;ABLIZ Zeper(Centre for Imaging&Systems Biology,College of Life and Environmental Sciences,Minzu University of China,Beijing 100081,China;State Key Laboratory of Bioactive Substances and Functions of Natural Medicines,Institute of Materia Medica,Chinese Academy of Medical Sciences and Peking Union Medical College,Beijing 100050,China)

机构地区：[1]中央民族大学生命与环境科学学院,生物成像与系统生物学研究中心,北京100081 [2]中国医学科学院,北京协和医学院药物研究所,天然药物活性物质与功能国家重点实验室,北京100050

出　　处：《分析化学》2018年第3期406-412,共7页Chinese Journal of Analytical Chemistry

基　　金：本文系国家民委领军人才、中央民族大学优秀青年人才和中央民族大学少数民族事业发展协同创新中心项目(No.2017MDYQ13)资助

摘　　要：质谱成像是近年来发展迅速的新型分子成像技术,在生物医药领域受到越来越广泛的关注。本研究采用敞开式的空气动力辅助离子化-高分辨质谱技术,建立了大鼠肾脏组织中内源性代谢物的质谱成像分析方法(AFAI-MSI)。大鼠肾脏组织经冷冻处理后制备冷冻组织切片,以乙腈-异丙醇-水(4∶4∶2,V/V)为喷雾溶剂,流速为5μL/min,喷雾气(N_2)压力为0.6 MPa,空气辅助气流速为45 L/min,质谱扫描范围为70~1000 Da,质量分辨率为70000。采用正离子检测模式的AFAI-MSI方法对大鼠肾脏组织切片进行了成像分析,结果发现有机胺、糖、神经递质、维生素、多肽、有机酸、甘油磷脂、鞘脂、甘油脂、固醇酯等38种不同类型、其含量差异达4个数量级的内源性代谢物,并观察到这些代谢物在肾脏中呈组织特异性分布,直观地呈现了与肾脏渗透压梯度形成有关的胆碱、乙酰胆碱、甜菜碱、磷酸胆碱和甘油磷酸胆碱等多种小分子代谢物的皮质-髓质轴向分布特征。上述结果表明,基于超高分辨质谱的AFAI-MSI分析方法无需样品预处理,灵敏度高,代谢物覆盖范围宽,可同时获取多种小分子代谢物的结构、含量及其空间分布信息,有望为肾脏中内源性代谢物的原位表征和代谢调控机制研究提供一种新的分析方法。As a promising new molecular imaging technique,mass spectrometry imaging(MSI)has attracted more and more attention in the field of biomedicine.A method of air flow assisted ionization-ultra high resolution mass spectrometry-based mass spectrometric imaging(AFAI-MSI)was developed to profile endogenous metabolites in rat kidney tissue in this study.Rat kidneys were collected and cut into frozen tissue sections,and then were analyzed on an AFAI-MSI system in positive ion mode using acetonitrile-isopmpyl alcohol-water(4:4:2,V/V,5μL/min)as spray solvent,N2 as spray gas(0.6 MPa)and air as assisting gas(45 L/min).The mass range and resolution were set to be 70-1000 Da and 70000,respectively.As a result,a total of 38 metabolites,including organic amines,sugars,vitamins,peptides,neurotransmitters,organic acids,phospholipids,sphingolipids,glyceride,and cholesterol esters,were identified and imaged to characterize their tissue-specific distribution in kidney tissues,and some metabolites,such as choline,acetylcoline,betaine,phoshocholine,and glycerophosphocholine were found to have distinct distribution along the cortex-medulla axis,which may be involved in the formation of osmotic pressure gradient in the kidney.The proposed ultra high resolution mass spectrometry based AFAI-MSI method could work without sample pretreatment,showed high sensitivity and wide metabolite coverage,and was expected to provide a new analytical approach for the research of in situ characterization and metabolic regulation mechanism of endogenous metabolites in kidney.

关 键 词：空气动力辅助离子化 质谱成像 小分子代谢物 肾脏 

分 类 号：O657.63[理学—分析化学] R310[理学—化学]