About: Dehydroascorbic acid is a research topic. Over the lifetime, 1531 publications have been published within this topic receiving 55457 citations. The topic is also known as: dehydroascorbate & DHAA.
Papers published on a yearly basis
TL;DR: It is found that SVCT1 and SVCT2 each mediate concentrative, high-affinity L-ascorbic acid transport that is stereospecific and is driven by the Na+ electrochemical gradient.
Abstract: Vitamin C (L-ascorbic acid) is essential for many enzymatic reactions, in which it serves to maintain prosthetic metal ions in their reduced forms (for example, Fe2+, Cu+), and for scavenging free radicals in order to protect tissues from oxidative damage. The facilitative sugar transporters of the GLUT type can transport the oxidized form of the vitamin, dehydroascorbic acid, but these transporters are unlikely to allow significant physiological amounts of vitamin C to be taken up in the presence of normal glucose concentrations, because the vitamin is present in plasma essentially only in its reduced form. Here we describe the isolation of two L-ascorbic acid transporters, SVCT1 and SVCT2, from rat complementary DNA libraries, as the first step in investigating the importance of L-ascorbic acid transport in regulating the supply and metabolism of vitamin C. We find that SVCT1 and SVCT2 each mediate concentrative, high-affinity L-ascorbic acid transport that is stereospecific and is driven by the Na+ electrochemical gradient. Despite their close sequence homology and similar functions, the two isoforms of the transporter are discretely distributed: SVCT1 is mainly confined to epithelial systems (intestine, kidney, liver), whereas SVCT2 serves a host of metabolically active cells and specialized tissues in the brain, eye and other organs.
TL;DR: No evidence for a role of oxidized glutathione or dehydroascorbate in the dark-deactivation of fructose bisphosphatase could be obtained, but addition of Paraquat to illuminated chloroplasts caused a rapid oxidation of reduced glutathion and ascorbate, and apparent loss of dehydroASCorbate.
Abstract: The stroma of spinach chloroplasts contains ascorbic acid and glutathione at millimolar concentrations. [Reduced glutathione]/[oxidized glutathione] and [ascorbate]/[dehydroascorbate] ratios are high under both light and dark conditions and no evidence for a role of oxidized glutathione or dehydroascorbate in the dark-deactivation of fructose bisphosphatase could be obtained. Addition of H2O2 to chloroplasts in the dark decreases the above ratios, an effect that is reversed on illumination. Addition of Paraquat to illuminated chloroplasts caused a rapid oxidation of reduced glutathione and ascorbate, and apparent loss of dehydroascorbate. Paraquat rapidly inactivated fructose bisphosphatase activity, as assayed under physiological conditions.
TL;DR: In this paper, a modification based on pre-generation of the ABTS radical anions with a thermolabile azo compound, 2,2'-azobis- (2-amidinopropane)HCl (ABAP), was described.
TL;DR: Ascorbate is proposed as a neuromodulator of glutamatergic, dopaminergic, cholinergic, and GABAergic transmission and related behaviors, posited to have potential therapeutic roles against ischemic stroke, Alzheimer's disease, Parkinson’s disease, and Huntington's disease.
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