日本質量分析学会 第67回質量分析総合討論会

演題概要

ポスター発表

第2日 5月16日(木)  P会場(多目的ホール)

親水性相互作用クロマトグラフィー質量分析法による哺乳類組織及び細胞に存在する内在性イノシトールポリ/ピロリン酸の検出と定量

(1東海大支援セ2東海大医・神経3フライブルグ大4ユニバーシティカレッジロンドン)
o伊藤誠敏1藤井奈津子2佐々木亜由美1田中政之1Jessen, Henning3Saiardi, Adolfo4永田栄一郎2

Myo-inositol phosphates (InsPs) play an important role in a variety of physiological functions in animals and plants. Among the InsPs, inositol pyrophosphates such as diphosphoinositol pentakisphosphate (InsP7), a highly-phosphorylated InsP generated from inositol hexakisphosphate (InsP6) by InsP6 kinases, are implicated in the development of cancer and neurodegenerative disorders. However, their precise roles remains elusive due to a lack of direct and sensitive methods to quantitate their abundance in biological samples.
We have recently developed an analytical method whereby InsP6 and InsP7 can be directly and sensitively determined using tandem mass spectrometry coupled with hydrophilic interaction liquid chromatography (HILIC)1). A polymer-based amino HILIC column, but not those with other chemical functionalities such as unmodified silica and zwitterionic group, achieved chromatographic separation of these InsPs with minimal peak tailing. Using this method, we succeeded at determining not only the amount of InsP6 in C57BL/6J mouse brain but also the concentrations of these InsPs in HEK293 cells before and after InsP7 induction by the NaF treatment. Furthermore, this analysis revealed the presence of endogenous InsP7 in human peripheral blood cells. Further improvement of this method is currently underway to simultaneously detect InsP8, another inositol pyrophosphate engendered by the phosphorylation of InsP7.