Handbook of Vitamin C Research

In: Handbook of Vitamin C Research ISBN: 978-1-60741-874-0Editors: Hubert Kucharski and Julek Zajac©2009 Nova Science Publishers, Inc.Chapter XIVVitamin C in the Treatmentof Endothelial DysfunctionAlin StirbanDiabetes Clinic, Heart and Diabetes Center NRW, Ruhr- University Bochum,Bad Oeynhausen, Germany.AbstractEndothelial dysfunction (ED) plays a critical role in the development ofcardiovascular complications preceding by decades their onset. Reversal of ED has beenpostulated to prevent atherosclerosis and several attempts have been done in thisdirection. Vitamin C has been suggested to reverse ED by several mechanisms: it servesas a potent antioxidant; it directly enhances the activity of nitric oxide synthase; the acylCoA oxidase system and counteracts the action of proinflammatory lipids. Multiple datafrom experimental and clinical studies have proven protective effects of vitamin C onendothelium. Though, the therapeutic indication is limited by the low biodisponibilityfollowing oral ascorbate administration and a rapid clearance. While oral, prophylacticapproaches of treatment with vitamin C are difficult to implement, a large body ofevidence prove beneficial effects of parenteral administration in critically ill patients.Supraphysiologic levels of ascorbate may facilitate the restoration of vascular function inpatients after severe burns and other major traumas. This translates clinically intoreduced circulatory shock, fluid requirements and oedema. The effects on themicrocirculation seem to be of particular interest since microcirculation is verysusceptible to oxidative stress that acts pathogenically to cause multiple organ failure.High-dose vitamin C administered parenterally counteracts endotoxin-induced ED andvasohyporeactivity in humans and reverses sepsis-induced alteration of themicrocirculation in animals.Tel.: 00495731 973724, email: astirban@hdz-nrw.de.