Department of Pathology, The University of Melbourne, Victoria, Australia.
Metallomics. 2011 Dec;3(12):1280-90. doi: 10.1039/c1mt00092f. Epub 2011 Sep 19.
Copper complexes of bis(thiosemicarbazone) (Cu(II)(btsc)s) have been studied as potential anti-cancer agents and hypoxia imaging agents. More recently, Cu(II)(btsc)s have been identified as possessing potent neuroprotective properties in cell and animal models of neurodegenerative disease. Despite their broad range of pharmacological activity little is known about how cells traffic Cu(II)(btsc)s and how this relates to potential anti-cancer or neuroprotective outcomes. One method of investigating sub-cellular localization of metal complexes is through confocal fluorescence imaging of the compounds in cells. Previously we harnessed the fluorescence of a pyrene group attached to diacetyl-bis(N4-methylthiosemicarbazonato)copper(ii)) (Cu(II)(atsm)), (Cu(II)L(1)). We demonstrated that Cu(II)L(1) was partially localized to lysosomes in HeLa cancer epithelial cells. Here we extend these studies to map the sub-cellular localization of Cu(II)L(1) in M17 neuroblastoma cells. Treatment of M17 or HeLa cells led to rapid association of the Cu-complex into distinct punctate structures that partially co-localized with lysosomes as assessed by co-localization with Lysotracker and acridine orange. No localization to early or late endosomes, the nucleus or mitochondria was observed. We also found evidence for a limited association of Cu(II)L(1) with autophagic structures, however, this did not account for the majority of the punctate localization of Cu(II)L(1). In addition, Cu(II)L(1) revealed partial localization with ER Tracker and was found to inhibit ER stress induced by tunicamycin. This is the first report to comprehensively characterize the sub-cellular localization of a Cu(II)(atsm) derivative in cells of a neuronal origin and the partial association with lysosome/autophagic structures and the ER may have a potential role in neuroprotection.
双（硫代缩氨基甲酸盐）（Cu(II)(btsc)s）的铜配合物已被研究作为潜在的抗癌和缺氧成像剂。最近，Cu(II)(btsc)s 已被确定为在神经退行性疾病的细胞和动物模型中具有强大的神经保护特性。尽管它们具有广泛的药理活性，但对于细胞如何运输 Cu(II)(btsc)s 以及这与潜在的抗癌或神经保护结果有何关系知之甚少。一种研究金属配合物亚细胞定位的方法是通过细胞中化合物的共焦荧光成像。之前，我们利用附着在二乙酰基双（N4-甲基硫代缩氨基甲酸盐）铜（ii）（Cu(II)(atsm)）（Cu(II)L(1)）上的芘基团的荧光。我们证明 Cu(II)L(1)在 HeLa 癌细胞上皮细胞中部分定位于溶酶体。在这里，我们将这些研究扩展到 M17 神经母细胞瘤细胞中 Cu(II)L(1)的亚细胞定位。在 M17 或 HeLa 细胞中处理导致 Cu-复合物迅速与明显的点状结构结合，这些点状结构与溶酶体部分共定位，如用 Lysotracker 和吖啶橙评估的那样。未观察到到早期或晚期内体、核或线粒体的定位。我们还发现了 Cu(II)L(1)与自噬结构的有限关联的证据，然而，这并没有解释 Cu(II)L(1)的大部分点状定位。此外，Cu(II)L(1)显示与 ER Tracker 的部分定位，并发现它可抑制衣霉素诱导的 ER 应激。这是首次全面描述神经元来源细胞中 Cu(II)(atsm)衍生物的亚细胞定位的报告，与溶酶体/自噬结构的部分关联和 ER 可能在神经保护中具有潜在作用。
