Yuan Min, Breitkopf Susanne B, Asara John M
Division of Signal Transduction, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States of America.
Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America.
PLoS One. 2017 Oct 13;12(10):e0186258. doi: 10.1371/journal.pone.0186258. eCollection 2017.
Horse urine is easily collected and contains molecules readily measurable using mass spectrometry that can be used as biomarkers representative of health, disease or drug tampering. This study aimed at analyzing microliter levels of horse urine to purify, identify and quantify proteins, polar metabolites and non-polar lipids. Urine from a healthy 12 year old quarter horse mare on a diet of grass hay and vitamin/mineral supplements with limited pasture access was collected for serial-omics characterization. The urine was treated with methyl tert-butyl ether (MTBE) and methanol to partition into three distinct layers for protein, non-polar lipid and polar metabolite content from a single liquid-liquid extraction and was repeated two times. Each layer was analyzed by high performance liquid chromatography-high resolution tandem mass spectrometry (LC-MS/MS) to obtain protein sequence and relative protein levels as well as identify and quantify small polar metabolites and lipids. The results show 46 urine proteins, many related to normal kidney function, structural and circulatory proteins as well as 474 small polar metabolites but only 10 lipid molecules. Metabolites were mostly related to urea cycle and ammonia recycling as well as amino acid related pathways, plant diet specific molecules, etc. The few lipids represented triglycerides and phospholipids. These data show a complete mass spectrometry based-omics characterization of equine urine from a single 333 μL mid-stream urine aliquot. These omics data help serve as a baseline for healthy mare urine composition and the analyses can be used to monitor disease progression, health status, monitor drug use, etc.
马尿易于收集，且含有可用质谱法轻松测量的分子，这些分子可用作代表健康、疾病或药物篡改情况的生物标志物。本研究旨在分析微升水平的马尿，以纯化、鉴定和定量蛋白质、极性代谢物和非极性脂质。采集了一匹12岁健康的夸特马母马的尿液，该马以草干草和维生素/矿物质补充剂为食，很少有机会接触牧场，用于进行系列组学表征。将尿液用甲基叔丁基醚（MTBE）和甲醇处理，通过单次液液萃取分成三个不同的层，分别用于分析蛋白质、非极性脂质和极性代谢物含量，并重复两次。对每一层进行高效液相色谱-高分辨率串联质谱分析（LC-MS/MS），以获得蛋白质序列和相对蛋白质水平，同时鉴定和定量小极性代谢物和脂质。结果显示有46种尿蛋白，许多与正常肾功能、结构和循环蛋白有关，还有474种小极性代谢物，但只有10种脂质分子。代谢物大多与尿素循环和氨再循环以及氨基酸相关途径、特定植物饮食分子等有关。少数脂质为甘油三酯和磷脂。这些数据展示了基于质谱的单份333微升中段尿马尿组学特征全貌。这些组学数据有助于作为健康母马尿液成分的基线，其分析可用于监测疾病进展、健康状况、监测药物使用等。
