Protective role of ascorbic acid against lipid peroxidation and myocardial injury.

Ascorbic acid (AH2) is a potential scavenger of superoxide radical and singlet oxygen. In the guinea pig, marginal AH2 deficiency results in intracellular oxidative damage in the cardiac tissue as evidenced by lipid peroxidation, formation of fluorescent pigment and loss of structural integrity of the microsomal membranes. The oxidative damage does not occur due to lack of enzymatic scavengers of reactive oxygen species such as superoxide dismutase, catalase and glutathione peroxidase. Also, glutathione transferase activity is not decreased in AH2 deficiency. Lipid peroxidation, fluorescent pigment formation and protein modification disappear after AH2 therapy. These results, if extra-polated to human beings, would indicate that chronic subclinical AH2 deficiency may result in progressive oxidative damage which in the long run may lead to permanent degenerative diseases in the heart.