Ascorbic acid protects against peroxidative modification of low-density lipoprotein, maintaining its recognition by LDL receptors.
J Nutr Sci Vitaminol (Tokyo). 2001 Feb ;47(1):28-31. PMID: 11349887
Peroxidatively modified low-density lipoprotein (LDL) may contribute to atherosclerotic processes; therefore, protecting LDL against peroxidation may thus reduce or retard the progression of atherosclerosis. We have evaluated the protective effects of ascorbic acid on copper-catalyzed LDL peroxidative modification. The protective effects of ascorbic acid on copper-catalyzed LDL peroxidative modification were examined by measurement of concentration of lipid hydroperoxides in LDL and by the provision of LDL cholesterol to lymphocytes via LDL receptor-mediated pathway. The measurement of concentration of lipid hydroperoxides in LDL showed that ascorbic acid inhibited peroxidative modification of LDL. Also, ascorbic acid preserved the ability of LDL to be recognized by LDL receptors in peripheral blood lymphocytes to the same extent as native LDL. These findings indicate that ascorbic acid may protect LDL against peroxidative modification, maintaining its ability to act as a ligand for LDL receptors in vivo.