Journal of Bioenergetics and Biomembranes

, Volume 26, Issue 4, pp 369-377

First online:

Dehydroascorbate reduction

  • William W. WellsAffiliated withDepartment of Biochemistry, Michigan State University
  • , Dian Peng XuAffiliated withDepartment of Biochemistry, Michigan State University

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access


Dehydroascorbic acid is generated in plants and animal cells by oxidation of ascorbic acid. The reaction is believed to occur by the one-electron oxidation of ascorbic acid to semidehydroascorbate radical followed by disproportionation to dehydroascorbic acid and ascorbic acid. Semidehydroascorbic acid may recycle to ascorbic acid catalyzed by membrane-bound NADH-semidehydroscorbate reductase. However, disproportionation of the free radical occurs at a rapid rate, 105 M−1 s−1, accounting for measurable cellular levels of dehydroascorbate. Dehydroascorbate reductase, studied earlier and more extensively in plants, is now recognized as the intrinsic activity of thioltransferases (glutaredoxins) and protein disulfide isomerase in animal cells. These enzymes catalyze the glutathione-dependent two-electron regeneration of ascorbic acid. The importance of the latter route of ascorbic acid renewal was seen in studies of GSH-deficient rodents (Meister, A. (1992)Biochem. Pharmacol. 44 1905–1915). GSH deficiency in newborn animals resulted in decreased tissue ascorbic acid and increased dehydroascorbate-to-ascorbate ratios. Administration of ascorbic acid daily to GSH-deficient animals decreased animal mortality and cell damage from oxygen stress. A cellular role is proposed for dehydroascorbate in the oxidation of nascent protein dithiols to disulfides catalyzed in the endoplasmic reticulum compartment by protein disulfide isomerase.

Key words

Dehydroascorbic acid ascorbic acid semidehydroascorbic acid glutathione glutathione: dehydroascorbate oxidoreductase NADH semidehydroascorbate reductase l-buthionine-SR-sulfoximine gastric ascorbate protein disulfide bonds protein disulfide isomerase