Antiangiogenic activity of Tripterygium wilfordii and its terpenoids

Ethnopharmacological relevance: Tripterygium wilfordii I look. f. (Celastraceae) has been traditionally used as folk medicine for centuries in China for the treatment of immune-inflammatory diseases. Aim of the study: This study aimed to assess the antiangiogenic activities which support the therapeutic use of Tripterygium wilfordii and its terpenoids for angiogenesis disease such as cancer. Materials and methods: The ethanol extract of Tripterygium wilfordii and subsequent fractions were evaluated on an in vivo antiangiogenic zebrafish embryo model. Results: Three antiangiogenic terpenoids were isolated by bioassay-guided purification, namely, celastrol (4), cangoronine (5) and triptolide (7). Among them, triptolide manifested the most patent antiangiogenic activity against vessel formation by nearly 50% at 1.2 mu M. Semi-quantitative RT-PCR analysis revealed that triptolide dose- and time-dependently reduced the mRNA expression of angiopoietin (angpt)2 and tie2 in zebrafish, indicating the involvement of angpt2/tie2 signaling pathway in the antiangiogenic action of triptolide. Conclusions: The discovery of an alternative pathway further confirms the value of ethnopharmacological investigations into traditional botanicals for leads for potential drug development. (c) 2008 Elsevier Ireland Ltd. All rights reserved.