Metabolomics study of cat small intestine during the early stage of Toxoplasma oocyst formation identifies potential biomarkers-pos raw datas

In this study, we used untargeted metabolomics technology to study the changes in metabolites that occurred during the early stage of oocyst formation in the cat small intestine following T. gondii infection and attempted to identify metabolic biomarkers that could potentially be used as diagnostic molecular markers in the future. Domestic cats (Felis catus) were infected with T. gondii Pru tissue cysts, and samples of their small intestinal epithelium were collected at 2 and 4 days post-infection (DPI) for metabolic analysis. LC-MS/MS and multivariate statistical analysis were employed to detect metabolomic signatures that discriminated between the infected and control groups. A total of 1,673 ions and 1,201 ions were obtained in the positive and negative modes, respectively. Of these ions, 175 were up-regulated and 127 were down-regulated in the positive ion mode; whereas, 123 were up-regulated and 81 were down-regulated in the negative ion mode. Three commonly altered ions (0.74_313.0414m/z, 8.82_615.2621m/z and 8.16_325.2362m/z) were determined to have potential research value. Seventy common metabolic pathways were enriched at two time points, with arginine biosynthesis, pyrimidine metabolism, pantothenate and CoA biosynthesis being the three most significant pathways related to T. gondii. The area under the curve (AUC) of differential metabolites combined with relevant literature analysis showed that N-Methylpelletierine and 3,3-Difluoro-17-methyl-5alpha-androstan-17beta-ol have higher predictability and better potential application value than other metabolites.

本研究采用非靶向代谢组学（untargeted metabolomics）技术，探究刚地弓形虫（Toxoplasma gondii，简称T. gondii）感染后，猫小肠内卵囊（oocyst）形成早期阶段的代谢物变化，并尝试鉴定未来可作为诊断分子标志物的潜在代谢生物标志物（metabolic biomarkers）。本研究以家猫（Felis catus）为实验对象，用刚地弓形虫Pru株组织包囊感染实验组猫，并分别于感染后第2天、第4天（days post-infection，DPI）采集小肠上皮样本开展代谢组学分析。本研究采用液相色谱-串联质谱（LC-MS/MS）与多变量统计分析（multivariate statistical analysis）方法，筛选可区分感染组与对照组的代谢组学特征标志物。在正离子模式与负离子模式下，分别共检测到1673个离子峰与1201个离子峰。其中正离子模式下有175个离子峰上调、127个下调；负离子模式下则有123个上调、81个下调。筛选得到3个在两组间均发生显著变化的离子峰（0.74_313.0414m/z、8.82_615.2621m/z与8.16_325.2362m/z），具备潜在研究价值。两个感染时间点共富集到70条共有代谢通路，其中精氨酸生物合成、嘧啶代谢、泛酸与辅酶A生物合成这三条通路与刚地弓形虫感染关联最为显著。结合相关文献分析对差异代谢物的受试者工作特征曲线下面积（area under the curve，AUC）进行评估，结果显示N-甲基石榴碱（N-Methylpelletierine）与3,3-二氟-17-甲基-5α-雄甾烷-17β-醇（3,3-Difluoro-17-methyl-5alpha-androstan-17beta-ol）相较其他代谢物具备更高的预测效能与更优的潜在应用价值。