Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, Colorado.
Vitalant Research Institute, Denver, Colorado.
Transfusion. 2020 Jun;60(6):1197-1211. doi: 10.1111/trf.15813. Epub 2020 May 11.
Coffee consumption is extremely common in the United States. Coffee is rich with caffeine, a psychoactive, purinergic antagonist of adenosine receptors, which regulate red blood cell energy and redox metabolism. Since red blood cell (purine) metabolism is a critical component to the red cell storage lesion, here we set out to investigate whether caffeine levels correlated with alterations of energy and redox metabolism in stored red blood cells.
We measured the levels of caffeine and its main metabolites in 599 samples from the REDS-III RBC-Omics (Recipient Epidemiology Donor Evaluation Study III Red Blood Cell-Omics) study via ultra-high-pressure-liquid chromatography coupled to high-resolution mass spectrometry and correlated them to global metabolomic and lipidomic analyses of RBCs stored for 10, 23, and 42 days.
Caffeine levels positively correlated with increased levels of the main red cell antioxidant, glutathione, and its metabolic intermediates in glutathione-dependent detoxification pathways of oxidized lipids and sugar aldehydes. Caffeine levels were positively correlated with transamination products and substrates, tryptophan, and indole metabolites. Expectedly, since caffeine and its metabolites belong to the family of xanthine purines, all xanthine metabolites were significantly increased in the subjects with the highest levels of caffeine. However, high-energy phosphate compounds ATP and DPG were not affected by caffeine levels, despite decreases in glucose oxidation products-both via glycolysis and the pentose phosphate pathway.
Though preliminary, this study is suggestive of a beneficial correlation between the caffeine levels and improved antioxidant capacity of stored red cells.
咖啡在美国的消费极为普遍。咖啡富含咖啡因，一种嘌呤能拮抗剂，可抑制腺苷受体，调节红细胞能量和氧化还原代谢。由于红细胞（嘌呤）代谢是红细胞储存损伤的关键组成部分，因此我们着手研究咖啡因水平是否与储存红细胞能量和氧化还原代谢的改变相关。
我们通过超高压液相色谱与高分辨率质谱联用，测量了来自 REDS-III RBC-Omics（受者流行病学供者评估研究 III 红细胞组学）研究的 599 个样本中的咖啡因及其主要代谢物的水平，并将其与储存 10、23 和 42 天的 RBC 的全球代谢组学和脂质组学分析相关联。
咖啡因水平与主要红细胞抗氧化剂谷胱甘肽及其在氧化脂质和糖醛酸的谷胱甘肽依赖解毒途径中的代谢中间产物的水平升高呈正相关。咖啡因水平与转氨基产物和底物色氨酸以及吲哚代谢物呈正相关。可以预期的是，由于咖啡因及其代谢物属于黄嘌呤嘌呤家族，所有黄嘌呤代谢物在咖啡因水平最高的受试者中均显著增加。然而，高能磷酸化合物 ATP 和 DPG 不受咖啡因水平的影响，尽管葡萄糖氧化产物减少，无论是通过糖酵解还是磷酸戊糖途径。
尽管初步研究，但该研究表明咖啡因水平与储存红细胞抗氧化能力的改善之间存在有益的相关性。
