Glutathione Deficiency Decreases Tissue Ascorbate Levels in Newborn Rats： Ascorbate Spares Glutathione and Protects [1991]; Alton Meister, Cornell University;_WJD_2016-0913_V001R01_IR93_IR94_

Glutathione Deficiency Decreases Tissue Ascorbate Levels in Newborn Rats： Ascorbate Spares Glutathione and Protects [1991]; Alton Meister, Cornell University;_WJD_2016-0913_V001R01_IR93_IR94_
Source (資訊來源):
http://www.jstor.org/stable/2357111?seq=1#page_scan_tab_contents
Info cited on 2016-09-13-WD2 (資訊引用於 中華民國105年9月13日) by 湯偉晉 (WeiJin Tang)
- - - - - - - - - - -
2016-09-13
Glutathione Deficiency Decreases Tissue Ascorbate Levels in Newborn Rats: Ascorbate Spares Glutathione and Protects

Glutathione Deficiency Decreases Tissue Ascorbate Levels in Newborn Rats: Ascorbate Spares Glutathione and Protects

Glutathione Deficiency Decreases Tissue Ascorbate Levels in Newborn Rats: Ascorbate Spares Glutathione and Protects
Johannes Mrtensson and Alton Meister
Proceedings of the National Academy of Sciences of the United States of America
Vol. 88, No. 11 (Jun. 1, 1991), pp. 4656-4660
Published by: National Academy of Sciences
Stable URL: http://www.jstor.org/stable/2357111
Page Count: 5

Abstract
Glutathione deficiency in newborn rats, produced by administration of L-buthionine-(S,R)-sulfoximine, a transition-state inactivator of γ-glutamylcysteine synthetase, decreases ascorbate levels of kidney, liver, brain, and lung. These tissues, especially their mitochondria, undergo severe damage and the animals die within a few days. When glutathione levels are markedly decreased, ascorbate levels decrease leading to formation of dehydroascorbate, which is degraded. Ascorbate has high antioxidant activity, but it (and other antioxidants such as α-tocopherol) must be maintained in reduced forms. These studies show in vivo that an important function of glutathione is to maintain tissue ascorbate. Administration of large doses of ascorbate (but not of dehydroascorbate) to buthionine sulfoximine-treated newborn rats decreases mortality, leads to normal levels of ascorbate, and spares glutathione. Newborn rats given lower doses of buthionine sulfoximine develop cataracts that, as shown previously, can be prevented by giving glutathione monoester; as found here, such cataracts can be partially prevented by administration of high doses of ascorbate or dehydroascorbate. Ascorbate spares glutathione indicating that these compounds have similar antioxidant actions. Ascorbate may have reductive functions that are not efficiently performed by glutathione. Although glutathione normally functions to maintain ascorbate, α-tocopherol, and other cellular components in reduced states, ascorbate can serve as an essential antioxidant in the presence of severe glutathione deficiency.

- - - - - - - - - - -