Resveratrol, a Polyphenolic Antioxidant in Red Wine, is Dose‐Dependent in Delivering Cardioprotection

Abstract

Recent studies have demonstrated cardioprotective abilities of resveratrol, a polyphenolic antioxidant present in red wine. Resveratrol can also kill cancer cells by exerting a death signal. We reasoned that resveratrol might possess the ability to protect the cells at lower dose as observed during preconditioning of the heart, while at higher dose, it causes cell death as found for cancer cells. The results demonstrated a reduction of PARP-1, Bcl-2 and Ref-1 in both the hearts of I/R and the animals fed high dose of resveratrol, while Akt expression remained unchanged. In contrast, low dose of resveratrol increased the expression of both Ref-1 and Bcl-2 proteins. The proapoptotic protein p53 and p-Bad was increased in the hearts subjected to I/R and further increased for the animals fed high dose of resveratrol while decreased in the hearts of the animals fed low dose of resveratrol. The infarction size increased in the rats that were given the high dose treatment compared to low dose. The results, thus, indicate that at low dose [25 mg/ kg], resveratrol exerts survival signal by upregulating anti-apoptotic and redox protein PARP-1, Bcl-2 and Ref-1 and down regulating proapoptotic p53 and p-Bad proteins. At high dose [100 mg/kg], it exerts death signal by producing the opposite effects. The infarct estimation studies show that high dose resveratrol does not protect the heart, but severely damages the heart tissue.