Fatty acid esters of hydroxy fatty acids (FAHFAs) are a new class of endogenous lipids with promising physiological functions in mammals. We previously introduced a new type of lipids to this family called short-chain fatty acid esters of hydroxy fatty acids (SFAHFAs), branching specific to the C2 carbon of a long-chain fatty acid (≥C20). In this study, we discovered a homologous series of SFAHFAs comprising C16-C26 hydroxy fatty acids esterified with short-chain fatty acids (C2-C5) in mouse colon contents. The detected SFAHFAs were characterized by high-resolution mass spectrometry with MSn analysis. The double-bond position of monounsaturated SFAHFAs was determined by the epoxidation reaction of samples with m-chloroperoxybenzoic acid and their MSn analysis. Further, the measurement of SFAHFA concentration in the colon contents of mice infected with influenza A/Puerto Rico/8/34 (H1N1; PR8) virus revealed a significant increase in their levels compared to native control. A strong correlation was observed between hydroxy fatty acid and SFAHFAs. Detection, characterization, and profiling of these new SFAHFA levels in relation with pandemic H1N1; PR8 influenza virus will contribute to the in-depth study of their function and metabolism.

中文翻译：

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通过 LTQ-Orbitrap-MS 检测小鼠结肠内容物中 SFAHFA 同源序列的结构特征及其在流感病毒感染中的意义。


羟基脂肪酸的脂肪酸酯（FAHFA）是一类新型内源性脂质，在哺乳动物中具有良好的生理功能。我们之前向该家族引入了一种新型脂质，称为羟基脂肪酸的短链脂肪酸酯 (SFAHFA)，其特定于长链脂肪酸 (≥C20) 的 C2 碳进行支化。在这项研究中，我们在小鼠结肠内容物中发现了一系列同源的 SFAFFA，其中包含用短链脂肪酸 (C2-C5) 酯化的 C16-C26 羟基脂肪酸。通过高分辨率质谱和 MSn 分析对检测到的 SFAFFA 进行了表征。通过样品与间氯过苯甲酸的环氧化反应及其 MSn 分析来确定单不饱和 SFAFAs 的双键位置。此外，对感染甲型/波多黎各/8/34（H1N1；PR8）流感病毒的小鼠结肠内容物中SFAFFA浓度的测量显示，与天然对照相比，其水平显着增加。羟基脂肪酸和 SFAFFA 之间观察到很强的相关性。检测、表征和分析与大流行 H1N1 相关的这些新 SFAFFA 水平； PR8流感病毒将有助于深入研究其功能和代谢。