Hickey James L, James Janine L, Henderson Clare A, Price Katherine A, Mot Alexandra I, Buncic Gojko, Crouch Peter J, White Jonathan M, White Anthony R, Smith Trevor A, Donnelly Paul S
The Florey Institute of Neuroscience and Mental Health , Parkville, Melbourne, Victoria 3052, Australia.
Inorg Chem. 2015 Oct 5;54(19):9556-67. doi: 10.1021/acs.inorgchem.5b01599. Epub 2015 Sep 23.
The intracellular distribution of fluorescently labeled copper and zinc bis(thiosemicarbazonato) complexes was investigated in M17 neuroblastoma cells and primary cortical neurons with a view to providing insights into the neuroprotective activity of a copper bis(thiosemicarbazonato) complex known as Cu(II)(atsm). Time-resolved fluorescence measurements allowed the identification of the Cu(II) and Zn(II) complexes as well as the free ligand inside the cells by virtue of the distinct fluorescence lifetime of each species. Confocal fluorescent microscopy of cells treated with the fluorescent copper(II)bis(thiosemicarbazonato) complex revealed significant fluorescence associated with cytoplasmic puncta that were identified to be lysosomes in primary cortical neurons and both lipid droplets and lysosomes in M17 neuroblastoma cells. Fluorescence lifetime imaging microscopy confirmed that the fluorescence signal emanating from the lipid droplets could be attributed to the copper(II) complex but also that some degree of loss of the metal ion led to diffuse cytosolic fluorescence that could be attributed to the metal-free ligand. The accumulation of the copper(II) complex in lipid droplets could be relevant to the neuroprotective activity of Cu(II)(atsm) in models of amyotrophic lateral sclerosis and Parkinson's disease.
研究了荧光标记的铜和锌双（硫代半卡巴腙）配合物在M17神经母细胞瘤细胞和原代皮层神经元中的细胞内分布，旨在深入了解一种名为Cu(II)(atsm)的铜双（硫代半卡巴腙）配合物的神经保护活性。时间分辨荧光测量能够凭借每种物质独特的荧光寿命识别细胞内的Cu(II)和Zn(II)配合物以及游离配体。用荧光铜（II）双（硫代半卡巴腙）配合物处理的细胞的共聚焦荧光显微镜显示，与细胞质斑点相关的显著荧光在原代皮层神经元中被鉴定为溶酶体，在M17神经母细胞瘤细胞中则为脂滴和溶酶体。荧光寿命成像显微镜证实，脂滴发出的荧光信号可归因于铜（II）配合物，但金属离子的一定程度损失也导致了可归因于无金属配体的弥漫性胞质荧光。脂滴中铜（II）配合物的积累可能与Cu(II)(atsm)在肌萎缩侧索硬化症和帕金森病模型中的神经保护活性有关。
