Duarte Tiago L, Lunec Joseph
Pharmaceutical Sciences Research Division, Kings College London University.
Free Radic Res. 2005 Jul;39(7):671-86. doi: 10.1080/10715760500104025.
Vitamin C (or ascorbic acid) is regarded as the most important water-soluble antioxidant in human plasma and mammalian cells which have mechanisms to recycle and accumulate it against a concentration gradient, suggesting that the vitamin might also have important intracellular functions. In this review we summarize evidence from human trials that have attempted an association between vitamin C supplementation and an effect on biomarkers of oxidative DNA damage. Most studies reviewed herein showed either a vitamin C-mediated reduction in oxidative DNA damage or a null effect, whereas only a few studies showed an increase in specific base lesions. We also address the possible beneficial effects of vitamin C supplementation for the prevention of cancer and cardiovascular disease. Finally, we discuss the contribution of cell culture studies to our understanding of the mode of action of vitamin C and we review recent evidence that vitamin C is able to modulate gene expression and cellular function, with a particular interest in cell differentiation.
维生素C（或抗坏血酸）被认为是人体血浆和哺乳动物细胞中最重要的水溶性抗氧化剂，这些细胞具有逆浓度梯度循环和积累维生素C的机制，这表明该维生素可能也具有重要的细胞内功能。在本综述中，我们总结了来自人体试验的证据，这些试验试图探寻补充维生素C与对氧化性DNA损伤生物标志物的影响之间的关联。本文综述的大多数研究显示，要么是维生素C介导的氧化性DNA损伤减少，要么是无效应，而只有少数研究显示特定碱基损伤增加。我们还探讨了补充维生素C对预防癌症和心血管疾病可能产生的有益作用。最后，我们讨论了细胞培养研究对我们理解维生素C作用模式的贡献，并综述了最近的证据，即维生素C能够调节基因表达和细胞功能，尤其关注细胞分化。
