The Effect of Epigallocatechin-3-Gallate on Intimal Hyperplasia after Vascular Grafting

Park, Han Ki; Park, Young Hwan; Song, Suk Won; Lee, Mi Hee; Park, Jong Chul; Joo, Huyn Chul; Chang, Byung Chul

Abstract

BACKGROUND: Intimal hyperplasia is characterized by a proliferation of vascular smooth muscle cells in the intimal layer. Epigallocatechin-3-gallate (EGCG) is known to suppress smooth muscle cell proliferation. We propose that EGCG may have a protective effect against the development of intimal hyperplasia through the suppression of smooth muscle cell proliferation. MATERIAL AND METHOD: Human umbilical vein endothelial cells (HUVEC) and rat aortic smooth muscle cells (RASMC) were cultured with different concentrations of EGCG, and proliferation and migration speed were measured. In 20 dogs, the autologous jugular veins were interposed into the carotid arteries. For the study group (n=10), the graft was stored for 30 minutes in EGCG solution and 300 mM EGCG was applied to the perivascular space after grafting. After 6 weeks, the intimal and medial thickness was measured. RESULT: The proliferation of RASMC and HUVEC was suppressed with EGCG. The migration of RASMC was suppressed with EGCG, but that of HUVEC was not affected. In the in vivo study, the intimal thickness was thinner in EGCG group than in the control group (p<0.05), but the medial thickness did not show any difference. The intimal/medial thickness ratio was lower in the EGCG group (p<0.05).
CONCLUSION
EGCG suppresses intimal hyperplasia after vascular grafting, and this may be mediated by prevention of migration and proliferation of vascular smooth muscle cells. The use of EGCG may offer new therapeutic modality to prevent intimal hyperplasia.