Green tea polyphenols as an anti-oxidant and anti-inflammatory agent for cardiovascular protection.

Our review aims to examine the cellular and molecular mechanisms of cardiovascular protection of green tea polyphenols, particularly epigallocatechin gallate (EGCG), which focuses on the anti-oxidative and anti-inflammatory effects. EGCG is the major and the most active component in green tea. Studies have shown that EGCG protects cellular damage by inhibiting DNA damage and oxidation of LDL. One of the protective properties of EGCG is its ability to scavenge free radicals. EGCG can also reduce the inflammatory response associated with local tissue injuries such as the hepatocellular necrosis in acute liver injury induced by carbon tetrachloride. The protective effect of EGCG is due to its ability to decrease lipid peroxidation, oxidative stress and the production of nitric oxide (NO) radicals by inhibiting the expression of iNOS. EGCG also ameliorates the overproduction of pro-inflammatory cytokines and mediators, reduces the activity of NF-kappaB and AP-1 and the subsequent formation of peroxynitrite with NO and reactive oxygen species. Thus, EGCG effectively mitigates cellular damage by lowering the inflammatory reaction and reducing the lipid peroxidation and NO generated radicals leading to the oxidative stress. Green tea is proposed to be a dietary supplement in the prevention of cardiovascular diseases in which oxidative stress and proinflammation are the principal causes.