Visualization of the cell-selective distribution of PUFA-containing phosphatidylcholines in mouse brain by imaging mass spectrometry

Previous studies have shown that MALDI-imaging mass spectrometry (IMS) can be used to visualize the distribution of various biomolecules, especially lipids, in the cells and tissues. In this study, we report the cell-selective distribution of PUFA-containing glycerophospholipids (GPLs) in the mouse brain. We established a practical experimental procedure for the IMS of GPLs. We demonstrated that optimization of the composition of the matrix solution and spectrum normalization to the total ion current (TIC) is critical. Using our procedure, we simultaneously differentiated and visualized the localizations of specific molecular species of GPLs in mouse brain sections. The results showed that PUFA-containing phosphatidylcholines (PCs) were distributed in a cell-selective manner: arachidonic acid-and docosahexaenoic acid-containing PCs were seen in the hippocampal neurons and cerebellar Purkinje cells, respectively. Furthermore, these characteristic localizations of PUFA-PCs were formed during neuronal maturation. The phenomenon of brain cell-selective production of specific PUFA-GPLs will help elucidate the potential physiological functions of PUFAs in specific brain regions.-Sugiura, Y., Y. Konishi, N. Zaima, S. Kajihara, H. Nakanishi, R. Taguchi, and M. Setou. Visualization of the cell-selective distribution of PUFA-containing phosphatidylcholines in mouse brain by imaging mass spectrometry. J. Lipid Res. 2009. 50: 1776-1788.

先前的研究表明，基质辅助激光解吸电离成像质谱（IMS）可用于观察各种生物分子，尤其是脂质在细胞和组织中的分布。在本研究中，我们报道了含多不饱和脂肪酸（PUFA）的甘油磷脂（GPLs）在小鼠大脑中的细胞选择性分布。我们建立了一种用于GPLs的IMS的实用实验流程。我们证明了基质溶液成分的优化以及对总离子流（TIC）进行光谱归一化至关重要。利用我们的流程，我们同时区分并观察到了小鼠脑切片中特定GPLs分子种类的定位。结果显示，含PUFA的磷脂酰胆碱（PCs）以细胞选择性的方式分布：含花生四烯酸和含二十二碳六烯酸的PCs分别在海马神经元和小脑浦肯野细胞中被观察到。此外，这些含PUFA的PCs的特征性定位是在神经元成熟过程中形成的。特定PUFA - GPLs在脑细胞中的选择性产生现象将有助于阐明PUFAs在特定脑区的潜在生理功能。——杉浦洋（Sugiura, Y.），小西佑（Y. Konishi），斋间直树（N. Zaima），梶原诚（S. Kajihara），中西浩（H. Nakanishi），田口良（R. Taguchi），濑户正人（M. Setou）。通过成像质谱观察含多不饱和脂肪酸的磷脂酰胆碱在小鼠大脑中的细胞选择性分布。《脂质研究杂志》2009年，50卷：1776 - 1788页。