Integrated Cancer Research Program, Rajiv Gandhi Centre for Biotechnology, Kerala, India.
Int J Nanomedicine. 2011;6:2113-22. doi: 10.2147/IJN.S24074. Epub 2011 Sep 23.
Several reports have demonstrated the anticancer activities of plumbagin, a naphthoquinone derivative isolated from plants belonging to Plumbaginaceae family. However, to the best of our knowledge, there are no reports which describe gold nanoconjugation with plumbagin, even though plumbagin is considered to be a promising therapeutic agent. In this report, we demonstrate the fabrication and characterization of gold nanoparticles conjugated with plumbagin (AuPB) that can reduce the toxicity of the latter, and their capacity for cellular localization and generation of reactive oxygen species. The anticancer activity and ability of plumbagin to produce reactive oxygen species was studied and compared with that of bromoderivatives of 1,4 naphthoquinones such as 2-bromo-1,4-naphthoquinone (2-BNQ) and 2,3-dibromo-1, 4-naphthoquinone (2,3-DBNQ) and their gold nanoconjugates. Plumbagin and bromoderivatives of 1,4 naphthoquinones in the form of gold nanoconjugates showed reduced cytotoxicity and apoptosis compared with the pristine compounds, ie, plumbagin, 2-BNQ, and 2,3-DBNQ. Interestingly, we observed that the gold nanoparticles could quench the reactive oxygen species-generating capacity of plumbagin, 2-BNQ, and 2,3-BNQ, which is one of the main mechanisms of action of the naphthoquinones. Therefore, it can be concluded that conjugation with gold nanoparticles can reduce the cytotoxicity of these compounds.
已有多项报告证实，从白花丹科植物中分离出的萘醌衍生物白花丹素具有抗癌活性。然而，据我们所知，目前还没有关于将白花丹素与金纳米结合的报道，尽管白花丹素被认为是一种很有前途的治疗剂。在本报告中，我们展示了金纳米与白花丹素（AuPB）结合的制备和表征，这种结合可以降低后者的毒性，以及它们的细胞定位和活性氧生成能力。我们研究了白花丹素的抗癌活性和产生活性氧的能力，并将其与 1,4 萘醌的溴代衍生物如 2-溴-1,4-萘醌（2-BNQ）和 2,3-二溴-1,4-萘醌（2,3-DBNQ）及其金纳米复合物进行了比较。以金纳米复合物形式存在的白花丹素和 1,4 萘醌的溴代衍生物的细胞毒性和细胞凋亡作用均低于原始化合物（即白花丹素、2-BNQ 和 2,3-DBNQ）。有趣的是，我们观察到金纳米粒子可以猝灭白花丹素、2-BNQ 和 2,3-DBNQ 产生活性氧的能力，这是萘醌类化合物的主要作用机制之一。因此，可以得出结论，与金纳米粒子结合可以降低这些化合物的细胞毒性。
