熊果酸对斑马鱼血管生成及斑马鱼移植癌的抑制作用

Inhibition of ursolic acid on angiogenesis and xenografts in zebrsfish (danio rerio)

目的研究熊果酸(ursolic acid,UA)对斑马鱼节间血管生成以及对斑马鱼移植癌的影响。方法采用AB系和转基因(trangenosis,TG)血管荧光斑马鱼(VEGFR2:GFP)作为实验模型动物,在荧光显微镜下观察不同剂量UA对斑马鱼胚胎背部节间血管(intersegment vessels,ISV)生成情况的影响;利用微量注射的方法分别建立斑马鱼的人肝癌细胞及肠腺癌斑马鱼的移植癌模型,在共聚焦显微镜下分别观察UA对肝癌细胞的影响,及人肠腺癌诱导的肠下静脉丛(subintestinal veins,SIVs)的变化,计算抑制率和SIVs生长情况,结果显微镜示UA 5与10 mg·L-1组引起TG斑马鱼节间荧光血管残缺或者缺失,抑制率分别为20.25%、26.65%;在斑马鱼肝癌SMMC-7721模型实验中,3个UA剂量组可减少移植肝癌细胞光密度(optical density,OD),抑制率分别为38.01%、54.69%(P<0.01)、61.88%(P<0.01),具有剂量依赖性;在斑马鱼移植瘤SIVs的实验中,UA 10 mg·L-1与15 mg·L-1组对移植癌诱导的SIVs增生有明显的抑制作用(P<0.01)。结论 UA对斑马鱼生理性及移植瘤引起的血管生成有明显抑制作用,这种抑制血管生成的作用与阻滞VEGFR2相关。

Aim To investigate the anti-angiogenesis and anti-xenograftes of UA in zebrafish larvaes. Meth-ods 24 hour post-fertilization ( hpf ) TG zebrafish was treated with different concentration of UA for 24h, and the number of intersegmental vessels( IVS) were detec-ted under fluorescent microscope respectively;then the models of AB/TG zebrafish xenografts were established by be micro-injected with SMMC-7721 or HT-29 cell at 48hpf respectively, and after cocultured with UA for 48h, optical density (OD) of the SMMC-7721 cell and subintestinal veins ( SIVs) induced by HT-29 were e-valuated under confocal microscope. Results ISV as-say showed that UA could cause IVS missing or disap-perance, inhibition ratio reaching 20. 25% and 26. 65%. UA blocked the spread of SMMC-7721 cells in zebrafish and OD value,and inhibition ratios at three concentrations were 38. 01%, 54. 69%, 61. 88%, re-spectively; in another SIVs assay induced by xeno-grafts, UA at concentration 10 and 15mg·L-1 showed that SIVs were inhibited (P<0. 01) obviously. Con-clusion UA could inhibit the angiogenesis and the growth of SMMC-7721/HT-29 xenografts,and the anti-tumor mechanism may be related with VEGFR2 expres-sion.