作者:Daniela Pucci、Alessandra Crispini、Bárbara Sanz Mendiguchía、Sante Pirillo、Mauro Ghedini、Sabrina Morelli、Loredana De Bartolo
DOI:10.1039/c3dt50513h
日期:——
New Zn(II)-curcumin based heteroleptic complexes (1–5) have been synthesized and fully characterized, with the aim to improve the bioactivity of the precursor derivative [(bpy-9)Zn(curc)Cl] (A), a potentially intercalating antitumor agent recently reported. Some structural changes have been made starting from the reference complex A, in order to introduce new functionalities, such as electrostatic and/or covalent interactions. In particular, keeping the same N,N chelating ligand, namely bpy-9, two completely different Zn(II) species have been obtained: a tetracoordinated Zn(II) cation with tetrafluoroborate as counterion (1) and a dimeric neutral complex in which the sulfate anion acts as a bridging group through two Zn(II) centres (2). Moreover, by changing the N,N chelating unit, [(Ln)Zn(curc)Cl] complexes (3–5), in which the Zn(II) ion shows the same pentacoordination seen in the precursor complex A, have been obtained. The antitumour activity of all new Zn(II) complexes was tested in vitro against the human neuroblastoma cell line SH-SY5Y in a biohybrid membrane system and the results indicate that all species exhibit strong cytotoxic activity. In particular the ionic tetrafluoroborate Zn(II) complex, 1, and the neutral phenanthroline based Zn(II) derivative, 4, show the strongest growth inhibition, being even more effective than the model complex A. Both complexes have a dose-dependent anti-proliferative effect on cells as demonstrated by the decrease of viability and the increase of Annexin V and PI-positive cells with the increase of their concentration. Cells treated with complexes 1 and 4 undergo apoptosis that involves the activation of JNK, caspase 3 and MMP changes. Finally, complex 1 is more effective in the induction of caspase-3 activation demonstrating its ability to trigger the execution-phase of cell apoptosis.
为了提高前体衍生物[(bpy-9)Zn(curc)Cl](A)的生物活性,我们合成了新的 Zn(II)-姜黄素异质配合物(1-5),并对其进行了全面表征。为了引入新的功能,如静电和/或共价相互作用,我们从参考复合物 A 开始对其结构进行了一些改变。特别是,在保留相同的 N,N 螯合配体(即 bpy-9)的情况下,得到了两种完全不同的 Zn(II):一种是以四氟硼酸盐为反离子的四配位 Zn(II)阳离子(1),另一种是二聚中性复合物,其中硫酸根阴离子作为桥基穿过两个 Zn(II)中心(2)。此外,通过改变 N,N 螯合单元,还得到了[(Ln)Zn(curc)Cl] 复合物(3-5),其中的 Zn(II)离子显示出与前体复合物 A 相同的五配位。在生物杂交膜系统中,针对人神经母细胞瘤细胞株 SH-SY5Y 对所有新型 Zn(II) 复合物的抗肿瘤活性进行了体外测试。尤其是离子型四氟硼酸锌(II)络合物 1 和中性菲罗啉基锌(II)衍生物 4 显示出最强的生长抑制作用,甚至比模型络合物 A 更有效。用复合物 1 和 4 处理的细胞会发生凋亡,其中包括 JNK、caspase 3 和 MMP 的活化变化。最后,复合物 1 在诱导 caspase-3 激活方面更为有效,这表明它有能力触发细胞凋亡的执行阶段。