Background. Urolithiasis is the process of stone formation in the urinary tract. Its etiology is only partly known, and efficient therapeutic approaches are currently lacking. Metabolomics is increasingly used in biomarkers discovery for its ability to identify mediators of relevant (patho)physiological processes. Amino acids may be involved in kidney stone formation. The aim of the present study was to investigate the presence of an amino acid signature in stone former urine through a targeted metabolomic approach. Methods. A panel of 35 amino acids and derivatives was assessed in urines from 15 stone former patients and 12 healthy subjects by UPLC-MS. Partial Least Squares Discriminant Analysis (PLS-DA) was used to define amino acid profiles of cases and controls. Results and Discussion. Our approach led to the definition of a specific amino acid fingerprint in people with kidney stones. A urinary amino acid profile of stone formers was characterized by lower levels of α-aminobutyric acid, asparagine, ethanolamine, isoleucine, methionine, phenylalanine, serine, tryptophan, and valine. Metabolomic analysis may lend insights into the pathophysiology of urolithiasis and allow tracking this prevalent condition over time.

中文翻译：

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特定的尿氨基酸特征是患有肾结石的人的特征。

背景。尿石症是泌尿道结石形成的过程。它的病因只是部分已知，目前缺乏有效的治疗方法。代谢组学因其识别相关（病理）生理过程介质的能力而越来越多地用于生物标志物的发现。氨基酸可能与肾结石的形成有关。本研究的目的是通过靶向代谢组学方法研究结石前尿液中氨基酸特征的存在。方法。通过 UPLC-MS 在 15 名结石病患者和 12 名健康受试者的尿液中评估了一组 35 种氨基酸和衍生物。偏最小二乘判别分析 (PLS-DA) 用于定义病例和对照的氨基酸谱。结果与讨论。我们的方法导致了肾结石患者特定氨基酸指纹的定义。结石形成者的尿氨基酸谱以较低水平的α-氨基丁酸、天冬酰胺、乙醇胺、异亮氨酸、蛋氨酸、苯丙氨酸、丝氨酸、色氨酸和缬氨酸为特征。代谢组学分析可能有助于深入了解尿石症的病理生理学，并允许随着时间的推移跟踪这种普遍情况。