Bird Susan S, Marur Vasant R, Stavrovskaya Irina G, Kristal Bruce S
Department of Neurosurgery, Brigham and Women's Hospital and, Department of Surgery, Harvard Medical School, 221 Longwood Avenue, LMRC-322, Boston, Massachusetts 02115.
Metabolomics. 2013 Mar;9(1 Suppl):67-83. doi: 10.1007/s11306-012-0400-1.
Lipids play multiple roles essential for proper mitochondrial function, from their involvement in membrane structure and fluidity, cellular energy storage, and signaling. Lipids are also major targets for reactive species, and their peroxidation byproducts themselves mediate further damage. Thousands of lipid species, from multiple classes and categories, are involved in these processes, suggesting lipid quantitative and structural analysis can help provide a better understanding of mitochondrial physiological status. Due to the diversity of lipids that contribute to and reflect mitochondrial function, analytical methods should ideally cover a wide range of lipid classes, and yield both quantitative and structural information. We developed a high resolution LC-MS method that is able to monitor the major lipid classes found in biospecimens (ie. biofluids, cells and tissues) with relative quantitation in an efficient, sensitive, and robust manner while also characterizing individual lipid side-chains, by all ion HCD fragmentation and chromatographic alignment. This method was used to profile the liver mitochondrial lipids from 192 rats undergoing a dietary macronutrient study in which changes in mitochondria function are related to changes in the major fat and glycemic index component of each diet. A total of 381 unique lipids, spanning 5 of the major LIPID MAPS defined categories, including fatty acyls, glycerophospholipids, glycerolipids, sphingolipids and prenols, were identified in mitochondria using the non-targeted LC-MS analysis in both positive and negative mode. The intention of this report is to show the breadth of this non-targeted LC-MS profiling method with regards to its ability to profile, identify and characterize the mitochondrial lipidome and the details of this will be discussed.
脂质对线粒体的正常功能起着多种至关重要的作用，包括参与膜结构和流动性、细胞能量储存以及信号传导。脂质也是活性物质的主要作用靶点，其过氧化副产物本身会介导进一步的损伤。数千种来自多个类别和种类的脂质参与了这些过程，这表明脂质定量和结构分析有助于更好地了解线粒体的生理状态。由于有助于并反映线粒体功能的脂质具有多样性，理想情况下，分析方法应涵盖广泛的脂质类别，并能提供定量和结构信息。我们开发了一种高分辨率液相色谱 - 质谱方法，该方法能够以高效、灵敏且稳健的方式对生物样本（即生物流体、细胞和组织）中发现的主要脂质类别进行相对定量监测，同时通过全离子HCD碎裂和色谱比对来表征单个脂质侧链。此方法用于对192只大鼠的肝脏线粒体脂质进行分析，这些大鼠正在进行一项膳食常量营养素研究，其中线粒体功能的变化与每种饮食中主要脂肪和血糖指数成分的变化相关。使用非靶向液相色谱 - 质谱分析在正离子和负离子模式下，在线粒体中总共鉴定出381种独特的脂质，涵盖了脂质代谢产物标准数据库（LIPID MAPS）定义的5个主要类别，包括脂肪酰基、甘油磷脂、甘油脂、鞘脂和萜类化合物。本报告的目的是展示这种非靶向液相色谱 - 质谱分析方法在分析、鉴定和表征线粒体脂质组方面的广度，并将讨论其详细信息。
