Resveratrol derivative, trans-3,5,4'-trimethoxystilbene, exerts antiangiogenic and vascular-disrupting effects in zebrafish through the downregulation of VEGFR2 and cell-cycle modulation.

Angiogenesis plays an important role in the development of neoplastic diseases such as cancer. Resveratrol and its derivatives exert antiangiogenic effects, but the mechanisms of their actions remain unclear. The aim of this study was to evaluate the antiangiogenic activity of resveratrol and its derivative trans-3,5,4'-trimethoxystilbene in vitro using human umbilical vein endothelial cells (HUVECs) and in vivo using transgenic zebrafish, and to clarify their mechanisms of action in zebrafish by gene expression analysis of the vascular endothelial growth factor (VEGF) receptor (VEGFR2/KDR) and cell-cycle analysis. trans-3,5,4'-Trimethoxystilbene showed significantly more potent antiangiogenic activity than that of resveratrol in both assays. In zebrafish, trans-3,5,4'-trimethoxystilbene caused intersegmental vessel regression and downregulated VEGFR2 mRNA expression. Trans-3,5,4'-trimethoxystilbene also induced G2/M cell-cycle arrest, most specifically in endothelial cells of zebrafish embryos. We propose that the antiangiogenic and vascular-targeting activities of trans-3,5,4'-trimethoxystilbene result from the downregulation of VEGFR2 expression and cell-cycle arrest at G2/M phase.

Effect of resveratrol on proliferation and differentiation of embryonic cardiomyoblasts.

Resveratrol (trans-3,5,4'-trihydroxystilbene), a polyphenolic compound found largely in the skins of red grapes, has been used as a nutritional supplement or an investigational new drug for prevention of cardiovascular diseases. Previous reports showed that resveratrol had a protective effect against oxidative agent-induced cell injury. Our studies indicate that resveratrol plays a role in the differentiation of cardiomyoblasts. The cardiomyoblast cell line, H9c2, was exposed to 30-120 microM resveratrol for up to 5 days. Resveratrol inhibits cardiomyoblast proliferation without causing cells injury. Moreover, resveratrol treatment modulated the differentiation of morphological characteristics including elongation and cell fusion in cardiomyoblasts. Proliferation and differentiation of H9c2 cells were further revealed by measurement of the mRNA expression of a cell cycle marker (CDK2), a differentiation marker (myogenin), and a contractile apparatus protein (MLC-2). Gene expression analysis revealed that resveratrol promoted entry into cell cycle arrest but extended the myogenic differentiation progress. These results have implications for the role of resveratrol in modulating cell cycle control and differentiation in cardiomyoblasts.