Holothurin B Isolated from Holothuria atra Inhibits Angiogenesis More Potent than Curcumin in Vitro

Background and objectives: Triterpene glycosides as the most bioactive components of sea cucumbers, have been considered for their various pharmacological properties especially anticancer and anti-metastasis activities. Due to the limited information on the biological properties of holothurin B as a marine triterpene glycoside, the present study aimed to examine its effect on angiogenesis and compare it with curcumin using human umbilical vein endothelial cells (HUVECs). Methods: Holothurin B was isolated from Holothuria atra and identified by NMR and Mass spectroscopic data. Cell survival was estimated using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) technique and migration of cells was assessed by Transwell test. Angiogenesis was evaluated in vitro by tube formation assay. Results: Holothurin B reduced HUVECs survival with IC50 value of 8.16 μg/mL. At the concentrations of 5 and 7.5 μg/mL, it significantly decreased the number of migrated cells, the average length and size of tubules, and mean number of junctions; it was more potent than curcumin. Conclusion: Holothurin B could be considered as a potent antiangiogenic constituent through suppressing endothelial cell proliferation, migration and tubulogenesis in vitro, suggesting its potential for further animal and clinical investigations.