Indian Council of Agricultural Research-Central Institute for Research on Buffaloes, Hisar, Haryana 125 001, India.
Indian Council of Agricultural Research-National Research Centre on Mithun, Nagaland 797 106, India.
J Proteomics. 2024 Aug 30;306:105259. doi: 10.1016/j.jprot.2024.105259. Epub 2024 Jul 15.
The present study investigated the urinary metabolic profiles of early pregnant and non-pregnant Mithun to identify potential pregnancy detection biomarkers. Urine samples were collected on days 0, 10, 18, 35 and 45 of gestation from pregnant (n = 6) and on days 0, 10 and 18 from non-pregnant (n = 6) Mithun. Urinary metabolites were assessed using proton nuclear magnetic resonance (H NMR) spectroscopy and identified 270 metabolites. Statistical analyses demonstrated pronounced distinctions in metabolite profiles between pregnant and non-pregnant samples. Twenty-five metabolites that could discriminate between pregnant and non-pregnant Mithun based on Variable Importance in Projection (VIP) scores >1 were identified. Upon further examination of six metabolites (kynurenine, kynurenate, 3-hydroxykynurenine, quinolinate, tyrosine and leucine) identified with high VIP scores, ROC curve analyses demonstrated their significant predictive potential, with AUC values ranging between 0.50 and 0.85. Additionally, a combined panel of top 25 metabolites yielded an AUC value of 0.85. Pathway analysis identified seven potential metabolic pathway modulations during early gestation, with particular emphasis on phenylalanine, tyrosine and tryptophan biosynthesis, tryptophan pathway and pathways involved in the metabolism of various amino acids. In conclusion, kynurenine, kynurenate, 3-hydroxykynurenine, quinolinate, tyrosine, and leucine show promise as non-invasive urinary biomarkers for early pregnancy detection in Mithun. SIGNIFICANCE: This study presents the first report on the metabolic profile of urine from early pregnant and non-pregnant Mithun (Bos frontalis). The metabolites like kynurenine and its derivatives (kynurenate, 3-hydroxykynurenine and quinolinate), tyrosine and leucine were documented signature urinary metabolites associated with early pregnancy in Mithun. The identified combination of metabolites holds promise as predictive biomarkers for non-invasive urinary-based early pregnancy diagnostics in Mithun. In addition, this study identified changes in metabolic pathways that involve phenylalanine, tyrosine, tryptophan and related amino acids and biomarkers identified were either precursors or products within these metabolic pathways.
本研究旨在探讨早期怀孕和未怀孕的羚牛尿液代谢谱，以鉴定潜在的妊娠检测生物标志物。采集怀孕（n=6）和未怀孕（n=6）羚牛在妊娠第 0、10、18、35 和 45 天及第 0、10 和 18 天的尿液样本。使用质子核磁共振（1H NMR）光谱法评估尿液代谢物，鉴定出 270 种代谢物。统计分析表明，怀孕和未怀孕样本的代谢谱存在明显差异。基于变量重要性投影（VIP）得分>1，鉴定出 25 种可区分怀孕和未怀孕羚牛的代谢物。进一步检查 6 种代谢物（犬尿氨酸、犬尿氨酸盐、3-羟基犬尿氨酸、喹啉酸、酪氨酸和亮氨酸），发现它们的 VIP 得分较高，ROC 曲线分析显示它们具有显著的预测潜力，AUC 值在 0.50 到 0.85 之间。此外，前 25 种代谢物的组合得到 AUC 值为 0.85。途径分析确定了妊娠早期七个潜在的代谢途径调节，特别强调了苯丙氨酸、酪氨酸和色氨酸的生物合成、色氨酸途径和各种氨基酸代谢途径。总之，犬尿氨酸、犬尿氨酸盐、3-羟基犬尿氨酸、喹啉酸、酪氨酸和亮氨酸有望成为羚牛早期妊娠检测的非侵入性尿液生物标志物。意义：本研究首次报道了早期怀孕和未怀孕羚牛尿液的代谢谱。代谢物如犬尿氨酸及其衍生物（犬尿氨酸盐、3-羟基犬尿氨酸和喹啉酸）、酪氨酸和亮氨酸被记录为与羚牛早期妊娠相关的特征性尿液代谢物。鉴定出的代谢物组合有望成为羚牛非侵入性尿液早期妊娠诊断的预测生物标志物。此外，本研究还发现了涉及苯丙氨酸、酪氨酸、色氨酸和相关氨基酸的代谢途径变化，所鉴定的生物标志物是这些代谢途径中的前体或产物。
