Green Tea Polyphenols Inhibit Oxidized LDL-induced NF-KB Activation in Human Umbilical Vein Endothelial Cells

Aim: To examine the anti-inflammatory effects of green tea polyphenols on oxLDL-mediated TNFalpha expression and NF-KB activation in the human umbilical vein endothelial cells (HUVECs).

Methods: We postulate that green tea polyphenols regulate TNF-alpha gene expression by modulating NF-KB activation through their inhibition effect on IKB Kinase (IKK) activity and as scavenger of free radicals. Pretreatment of green tea polyphenols reduced oxLDL-induced production of proinflammatory cytokine TNF-alpha and NF-KB activation in dose dependent manner (p < 0.05). Post hoc comparison test with Mann Whitney between various dosage of green tea polyphenols in inhibition of NF-KB activation showed significant result (p < 0.05).

Results: In TNF-alpha expression, there was also declined TNF-alpha productions (p 0.09; 0.2 vs 0.4mg/ml: ns). The effect of green tea polyphenols on TNF-alpha expression were determined by Mann-Whitney test. There is significant difference between the first dose (0.1mg/ml) vs 0.2mg/ml polyphenols (p=0.009); between 0.1 vs 0.4 mg/ml polyphenols (p=0.009). There was no difference when the dose was increased from 0.2 mg/ml to 0,4 mg/ml polyphenols (0.141). In this study, green tea polyphenols showed significant effects on the inhibition of TNF-alpha through NF-KB activation pathway in HUVECs with oxidized LDL.

Conclusion: Green tea polyphenol can be used to prevent the development of atherosclerosis.