Among the natural products screened in Tg(fli1a: EGFP)y1 zebrafish, mundoserone was identified as an anti-angiogenic compound. Representative (A-C) bright-field and (D-F) fluorescent images of zebrafish embryos at 24 h post-fertilization treated with 0.1% dimethyl sulfoxide (control), 10 µM mundoserone or 5 µM PTK787 (positive control) for 24 h (magnification, ×40). (G-I) Magnification of images (D-F) (magnification, ×112.5). Compared with those in the control group, embryos treated with mundoserone presented with a lower number of incomplete ISVs and only occasional sprouts (asterisks) of the DA were observed. (J) Chemical structure of mundoserone. DLAV, dorsal longitudinal anastomotic vessels; ISVs, intersegmental vessels; DA, dorsal aorta; PCV, posterior cardinal vein.

Mundoserone inhibits the trunk angiogenesis of zebrafish in a dose-dependent manner. Representative (A-E) bright field and (F-J) fluorescent images of zebrafish embryos at 24 h post-fertilization treated with 0.1% dimethyl sulfoxide (control), mundoserone (2.5, 5 or 10 µM) or 5 µM PTK787 (positive control) for 24 h (magnification, ×40). (K-O) Magnification of images F-J (magnification, ×112.5). Compared with the control, embryos exposed to mundoserone exhibited a lower number of incomplete ISVs and only occasional sprouts (asterisks) of the DA were observed. Quantification of (P) the number of complete ISVs and (Q) inhibition rate in mundoserone-treated embryos. Values are expressed as the mean ± standard error of the mean (n=10). ***P<0.001. ns, not significant; DLAV, dorsal longitudinal anastomotic vessels; ISVs, intersegmental vessels; DA, dorsal aorta; PCV, posterior cardinal vein.