TitleLipoic acid and vitamin C potentiate nitric oxide synthesis in human aortic endothelial cells independently of cellular glutathione status.
Publication TypeJournal Article
Year of Publication2002
AuthorsVisioli F, Smith A, Zhang W, Keaney JF, Hagen T, Frei B
JournalRedox Rep
Date Published2002
KeywordsAntioxidants, Aorta, Ascorbic Acid, Endothelium, Vascular, Glutathione, Humans, Nitric Oxide, Nitric Oxide Synthase, Nitric Oxide Synthase Type III, Pyrrolidonecarboxylic Acid, Thiazoles, Thiazolidines, Thioctic Acid

Vitamin C and thiol agents improve vasomotor function. To determine whether these compounds directly affect endothelial function, nitric oxide (NO) synthesis was measured in human aortic endothelial cells treated with ascorbic acid or the thiol modulating agents lipoic acid or L-2-oxothiazolidine-4-carboxylic acid (OTC). A dose-dependent increase in A23187-stimulated NO synthesis and elevated cGMP levels were observed in all cases except for OTC. Cellular GSH levels were not significantly increased, and the GSH/GSSG ratio was not significantly affected by treatment of the cells with lipoic acid, OTC, or ascorbic acid. Thus, vitamin C and lipoic acid potentiate endothelial NO synthesis and bioactivity by mechanisms that appear to be independent of cellular GSH levels and redox environment.

Alternate JournalRedox Rep.
PubMed ID12396668
Grant ListHL60886 / HL / NHLBI NIH HHS / United States