From our daily nutrition and synthesis within cells, nucleosides enter the bloodstream and circulate throughout the body and tissues. Nucleosides and nucleotides are classically viewed as precursors of nucleic acids, but recently they have emerged as a novel energy source for central carbon metabolism. Through catabolism by nucleoside phosphorylases, the ribose sugar group is released and can provide substrates for lower steps in glycolysis. In environments with limited glucose, such as at sites of infection or in the tumor microenvironment (TME), cells can use, and may even require, this alternative energy source. Here, we discuss the implications of these new findings in health and disease and speculate on the potential new roles of nucleosides and nucleic acids in energy metabolism.

中文翻译：

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核苷是中心碳代谢中被忽视的燃料

从我们日常的营养和细胞内的合成中，核苷进入血液并在整个身体和组织中循环。核苷和核苷酸传统上被视为核酸的前体，但最近它们已成为中心碳代谢的新型能源。通过核苷磷酸化酶的分解代谢，核糖基团被释放，并可为糖酵解的较低步骤提供底物。在葡萄糖有限的环境中，例如在感染部位或肿瘤微环境（TME）中，细胞可以使用甚至可能需要这种替代能源。在这里，我们讨论这些新发现对健康和疾病的影响，并推测核苷和核酸在能量代谢中的潜在新作用。