Division of Gastroenterology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Faculty of Medicine, Department of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
Department of Chemistry and Biochemistry, National Chung Cheng University, 168 University Road, Ming-Hsiung, Chia Yi 62142, Taiwan.
Clin Chim Acta. 2022 Jun 1;531:137-144. doi: 10.1016/j.cca.2022.03.023. Epub 2022 Apr 1.
Overproduction of the reactive oxygen, nitrogen, and chlorine species by the immune systems during chronic infection and inflammation can cause structural and functional changes of cellular proteins. The high abundance of hemoglobin in blood makes hemoglobin adducts suitable biomarkers for assessing the damage of these reactive species in the body. In this study, a total of 23 types and sites of modification in human hemoglobin were simultaneously analyzed, including monooxygenation of histidine, tyrosine, methionine, and aspartate, conversion of histidine to aspartate and hydroxyaspartate, as well as chlorination and nitration of tyrosine residues. Hemoglobin was isolated from the blood of the study subjects, digested into peptides, and the extents of these modifications were quantified relative to their parent peptides using nanoflow liquid chromatography nanoelectrospray ionization tandem mass spectrometry under selected reaction monitoring (nanoLC - NSI-MS/MS-SRM). The extents of monooxygenation at β-His-77 and β-Tyr-130, chlorination at α-Tyr-24 and β-Tyr-130, and nitrosylation at α-Tyr-24 were elevated in gastric cancer patients. Conversely, conversion of histidine to aspartate at α-His-20, α-His-50, β-His-2, β-His-143, and monooxygenation at β-His-143 were decreased in gastric cancer patients. The areas under the receiver operating characteristics (AUC of ROC) curve of these ten types and sites of hemoglobin modifications were between 0.7644 and 0.9644. The ratio of conversion of histidine to hydroxyaspartate versus conversion of histidine to aspartate was significantly higher in gastric cancer patients at α-His-20, α-His-50, and β-His-143 (p < 0.05) with AUC of ROC ranging between 0.7689 and 0.9178. To our knowledge, this is the first report of simultaneous measurement of multiple types of oxidative and advanced oxidative hemoglobin modifications in gastric cancer patients. The results revealed elevated levels of oxidative stress-induced protein damage in gastric cancer patients and the potential of using these modifications of hemoglobin as biomarkers for evaluation of oxidative stress in one drop of blood.
在慢性感染和炎症过程中，免疫系统过度产生活性氧、氮和氯物种会导致细胞蛋白的结构和功能发生变化。血液中血红蛋白的高含量使血红蛋白加合物成为评估体内这些活性物质损伤的合适生物标志物。在这项研究中，共同时分析了人血红蛋白的 23 种类型和部位的修饰，包括组氨酸、酪氨酸、蛋氨酸和天冬氨酸的单加氧、组氨酸转化为天冬氨酸和羟天冬氨酸，以及酪氨酸残基的氯化和硝化。从研究对象的血液中分离出血红蛋白，将其消化成肽，并使用纳流液相色谱纳喷雾电离串联质谱在选择反应监测（nanoLC-NSI-MS/MS-SRM）下相对于其母体肽定量这些修饰的程度。胃癌患者β-His-77 和 β-Tyr-130 的单加氧、α-Tyr-24 和 β-Tyr-130 的氯化以及α-Tyr-24 的亚硝基化程度升高。相反，胃癌患者α-His-20、α-His-50、β-His-2、β-His-143 的组氨酸向天冬氨酸的转化以及β-His-143 的单加氧程度降低。这十种类型和部位的血红蛋白修饰的受试者工作特征（ROC）曲线下面积（AUC of ROC）在 0.7644 至 0.9644 之间。胃癌患者α-His-20、α-His-50 和β-His-143 组组氨酸转化为羟天冬氨酸与组氨酸转化为天冬氨酸的比值明显更高（p<0.05），ROC 曲线下面积在 0.7689 至 0.9178 之间。据我们所知，这是首次报道同时测量胃癌患者多种类型的氧化和高级氧化血红蛋白修饰。结果表明，胃癌患者的氧化应激诱导蛋白损伤水平升高，并且有可能使用一滴血中的血红蛋白这些修饰作为评估氧化应激的生物标志物。
