@article {Li:May 2007:0022-3573:739, author = "Li, Guo-Xiang", author = "Tang, You-Zhi", author = "Liu, Zai-Qun", title = "The "double-faced" effect of VC-12 on free-radical-induced haemolysis of human erythrocytes: antioxidant and prooxidant", journal = "Journal of Pharmacy and Pharmacology", volume = "59", year = "May 2007", abstract = "Vitamin C is a popular antioxidant; however, its water solubility limits its function in the lipid environment. As a result, the antioxidative properties of its lipophilic derivatives have aroused research attention, especially L-ascorbyl-6-laurate (VC-12). We have investigated the effect of a high concentration of VC-12 on 2,2′-azobis(2-amidinopropane hydrochloride) (AAPH)-induced haemolysis of human erythrocytes. The findings indicated that VC-12 was capable of protecting erythrocytes against AAPH-induced haemolysis when its concentration was below 60 μM. With an increase in the concentration of VC-12 and a decrease in the concentration of AAPH, VC-12 promoted haemolysis remarkably, the mechanism of which has been proposed as VC-12-mediated peroxidation. When the concentration of VC-12 was increased to above 150 μM, VC-12 promoted haemolysis by its function as a surfactant, to unbalance the osmotic pressure within and outside erythrocytes. High concentrations of VC-12 may have generated radicals via autooxidation, resulting in eventual haemolysis. Therefore, the double-faced effect of VC-12 on haemolysis of human erythrocytes was due to its concentration. This information may be useful for the safe use of lipophilic vitamin C.", pages = "739-743(5)", url = "http://www.ingentaconnect.com/content/rpsgb/jpp/2007/00000059/00000005/art00016" doi = "doi:10.1211/jpp.59.5.0016" }