Abstract

It has been suggested that thiol-containing amino acids could be used as biomarkers for diseases associated with oxidative stress. We investigated the thiol-containing amino acids, homocysteine (Hcy), cysteine (Cys), glutathione (GSH) and γ-glutamylcysteine (γ-GluCys), in commercial human serum by using liquid chromatography–tandem mass spectrometry (LC–MS/MS) after precolumn derivatization with 4-fluoro-7-sulfobenzofurazan. This method was applied to determine the composition of thiol-containing amino acids in exosomes prepared from the serum. Hcy, Cys, GSH and γ-GluCys could be detected in the exosomal fraction, and the ratio of each thiol-containing amino acid was similar to those in the corresponding native serum. Cys (94.76%) was most enriched in the exosomal fraction, followed by GSH (2.97%), γ-GluCys (1.59%) and Hcy (0.68%). These findings suggest that thiol-containing amino acids, Hcy, Cys, GSH and γ-GluCys, are included in exosomes in human serum.

中文翻译：

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血清外泌体中含硫醇氨基酸的LC-MS / MS分析。

摘要

已经提出，含硫醇的氨基酸可用作与氧化应激有关的疾病的生物标记。我们使用液相色谱-串联质谱（LC-MS / MS）对商业人血清中的含硫醇氨基酸，高半胱氨酸（Hcy），半胱氨酸（Cys），谷胱甘肽（GSH）和γ-谷氨酰半胱氨酸（γ-GluCys）进行了研究。 MS）用4-氟-7-磺基苯并呋喃酯预柱衍生后 该方法用于确定由血清制备的外泌体中含硫醇氨基酸的组成。在外泌体组分中可以检测到Hcy，Cys，GSH和γ-GluCys，每种含硫醇氨基酸的比例与相应的天然血清中的相似。Cys（94.76％）在外泌体组分中含量最高，其次是GSH（2.97％），γ-GluCys（1.59％）和Hcy（0.68％）。