It is thought that vitamin C has protective roles on stress-induced heart damage and the development of cardiovascular diseases, but its precise role and mechanisms are unclear. In the present study, we investigated the specific mechanisms by which vitamin C leads to protecting the heart from stress-induced damage in the Gulo(-/-) mice which cannot synthesize vitamin C like humans. By exposure to stress (1h/day), the heartbeat and cardiac output in vitamin C-insufficient Gulo(-/-) mice were definitely decreased, despite a significant increase of adrenaline (ADR) and noradrenaline (NA) production. A change of cardiac structure caused by the death of cardiomyocytes and an increased expression of matrix metalloprotease (MMP)-2 and -9 were also found. Moreover, lipid peroxidation and the production of tumor necrosis factor-alpha (TNF-α) in the heart were increased. Finally, all vitamin C-insufficient Gulo(-/-) mice were expired within 2 weeks. Interestingly, all of the findings in vitamin C-insufficient Gulo(-/-) mice were completely prevented by the supplementation of a sufficient amount of vitamin C. Taken together, vitamin C insufficiency increases the risk of stress-induced cardiac damage with structural and functional changes arising from the apoptosis of cardiomyocytes.
Kim H, Bae S, Kim Y, Cho CH, Kim SJ, Kim YJ, Lee SP, Kim HR, Hwang YI, Kang JS, Lee WJ.