ReviewPart of the Series: From Dietary Antioxidants to Regulators in Cellular Signalling and Gene ExpressionReview: When is an antioxidant not an antioxidant? A review of novel actions and reactions of vitamin C

@article{Duarte2005ReviewPartOT,
  title={ReviewPart of the Series: From Dietary Antioxidants to Regulators in Cellular Signalling and Gene ExpressionReview: When is an antioxidant not an antioxidant? A review of novel actions and reactions of vitamin C},
  author={Tiago L Duarte and Joseph Lunec},
  journal={Free Radical Research},
  year={2005},
  volume={39},
  pages={671 - 686}
}
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… Expand
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Vitamin C modulation of H2O2-induced damage and iron homeostasis in human cells.
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References

SHOWING 1-10 OF 144 REFERENCES
Vitamin C and genomic stability.
TLDR
There is limited evidence that supplements of Vitamin C might have beneficial effects in disorders of vascular function, and that diet-derived Vitamin C may decrease gastric cancer incidence in certain populations, but it is not clear whether it is the antioxidant or other properties of ascorbate that are responsible for these two actions. Expand
Does vitamin C act as a pro‐oxidant under physiological conditions?
  • A. Carr, B. Frei
  • Medicine, Biology
  • FASEB journal : official publication of the Federation of American Societies for Experimental Biology
  • 1999
TLDR
Although the data on protein oxidation in humans are sparse and inconclusive, the available data in animals consistently show an antioxidant role of vitamin C, both in the presence and absence of metal ions. Expand
Novel repair action of vitamin C upon in vivo oxidative DNA damage
TLDR
The kinetics of 8‐oxo‐2′‐deoxyguanosine removal and processing in vivo are illustrated, for the first time in humans, suggesting a role for vitamin C in the regulation of DNA repair enzymes and thereby demonstrating a non‐scavenging antioxidant effect. Expand
The effect of vitamin C or vitamin E supplementation on basal and H2O2-induced DNA damage in human lymphocytes
TLDR
These supplementation regimens may be used to limit the possible adverse effects of reactive oxygen species (including those produced during the course of an immune response) on lymphocytes in vivo, and so help to maintain their functional capacity. Expand
Vitamin C-Induced Decomposition of Lipid Hydroperoxides to Endogenous Genotoxins
TLDR
It is determined that vit C induces lipid hydroperoxide decomposition to the DNA-reactive bifunctional electrophiles 4-oxo-2-nonenal, 4,5-epoxy-2(E)-decenal), and 4-hydroxy- 2-nonnal, a precursor of etheno- 2′-deoxyadenosine, a highly mutagenic lesion found in human DNA. Expand
Vitamins C and E: acute interactive effects on biomarkers of antioxidant defence and oxidative stress.
TLDR
The data from this first controlled study of acute effects of single doses of Vitamin C and/or E show no evidence of either a protective or deleterious effect on DNA damage, resistance of DNA to oxidant challenge, or lipid peroxidation. Expand
Evidence that dietary supplementation with carotenoids and carotenoid-rich foods modulates the DNA damage:repair balance in human lymphocytes
TLDR
The results suggest that carotenoids andCarotenoid-rich foods can influence DNA damage:repair by modulation of discrete stages in the DNA repair mechanisms. Expand
New evidence for antioxidant properties of vitamin C.
TLDR
It is concluded that ascorbic acid is an antioxidant and that doses up to 5,000 mg neither induce mutagenic lesions nor have negative effects on NK cell activity, apoptosis, or cell cycle. Expand
Vitamin C supplementation decreases oxidative DNA damage in mononuclear blood cells of smokers
TLDR
This study suggests that long-term vitamin C supplementation at high dose, i. Expand
Ascorbic acid oxidation product(s) protect human low density lipoprotein against atherogenic modification. Anti- rather than prooxidant activity of vitamin C in the presence of transition metal ions.
TLDR
The data indicate that vitamin C protects LDL against atherogenic modification by two different mechanisms that may act in concert: (i) free radical scavenging by AA prevents aqueous oxidants from attacking and oxidizing LDL, and (ii) stable modification of LDL by DHA or decomposition product(s) thereof imparts increased resistance to metal ion-dependent oxidation. Expand
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