Xia Hongmei, Tang Chengyi, Gui Heng, Wang Xiaoming, Qi Jinliang, Wang Xiuqiang, Yang Yonghua
*State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210093, People's Republic of China.
Biosci Rep. 2013 Feb 1;33(2):e00020. doi: 10.1042/BSR20120065.
Shikonin has anticancer activity, but it has not yet been applied into clinical use. In the present study, shikonin was prepared using liposomes. We aimed to examine several aspects of sh-L (shikonin-containing liposomes): preparation, angiogenic suppression and cellular uptake through self-fluorescence. Sh-L were prepared using soybean phospholipid and cholesterol to form the membrane and shikonin was encapsulated into the phospholipid membrane. Three liposomes were prepared with shikonin. They had red fluorescence and were analysed using a flow cytometer. Angiogenic suppression of sh-L was determined using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide], Transwell tests, chick CAM (chorioallantoic membrane) and Matrigel™ plug assay. MTT assay showed the median IC₅₀ (inhibitory concentrations) as follows: shikonin, sh-L₁ and sh-L₂ were 4.99±0.23, 5.81±0.57 and 7.17±0.69 μM, respectively. The inhibition rates of migration were 53.58±7.05, 46.56±4.36 and 41.19±3.59% for 3.15 μM shikonin, sh-L₁ and sh-L₂, respectively. The results of CAM and Matrigel plug assay demonstrated that shikonin and sh-L can decrease neovascularization. Effect of shikonin was more obvious than sh-L at the same concentration. The results showed that sh-L decreased the toxicity, the rate of inhibition of migration and angiogenic suppression. The cellular uptake of the sh-L could be pictured because of the self-fluorescence. The self-fluorescence will be useful for conducting further research. Sh-L might be an excellent preparation for future clinical application to cancer patients.
紫草素具有抗癌活性，但尚未应用于临床。在本研究中，采用脂质体制备了紫草素。我们旨在研究含紫草素脂质体（sh-L）的几个方面：制备、血管生成抑制以及通过自身荧光进行细胞摄取。使用大豆磷脂和胆固醇形成膜来制备sh-L，紫草素被包裹在磷脂膜中。用紫草素制备了三种脂质体。它们具有红色荧光，并使用流式细胞仪进行分析。使用MTT [3-(4,5-二甲基噻唑-2-基)-2,5-二苯基-2H-四氮唑溴盐]、Transwell试验、鸡胚绒毛尿囊膜（CAM）和基质胶™ 栓塞试验来测定sh-L的血管生成抑制作用。MTT试验显示的半数抑制浓度（IC₅₀）如下：紫草素、sh-L₁和sh-L₂分别为4.99±0.23、5.81±0.57和7.17±0.69 μM。对于3.15 μM的紫草素、sh-L₁和sh-L₂，迁移抑制率分别为53.58±7.05%、46.56±4.36%和41.19±3.59%。CAM和基质胶栓塞试验的结果表明，紫草素和sh-L均可减少新血管形成。在相同浓度下，紫草素的效果比sh-L更明显。结果表明，sh-L降低了毒性、迁移抑制率和血管生成抑制作用。由于自身荧光，可以观察到sh-L的细胞摄取情况。这种自身荧光将有助于进行进一步的研究。sh-L可能是未来用于癌症患者临床应用的一种优秀制剂。
