School of Chemical Sciences, National Institute for Cellular Biotechnology, Dublin City University Dublin, Ireland.
Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche Bologna, Italy ; Institute of Nanoscience and Nanotechnology, National Center for Scientific Research "Demokritos," Athens, Greece.
Front Chem. 2015 Apr 21;3:28. doi: 10.3389/fchem.2015.00028. eCollection 2015.
The deleterious effects of metal-catalyzed reactive oxygen species (ROS) in biological systems can be seen in a wide variety of pathological conditions including cancer, cardiovascular disease, aging, and neurodegenerative disorder. On the other hand however, targeted ROS production in the vicinity of nucleic acids-as demonstrated by metal-activated bleomycin-has paved the way for ROS-active chemotherapeutic drug development. Herein we report mechanistic investigations into the oxidative nuclease activity and redox properties of copper(II) developmental therapeutics Cu(DPQ)(phen) (Cu-DPQ-Phen), Cu(DPPZ)(phen) (Cu-DPPZ-Phen), and {Cu(phen)2}2(μ-terph) (Cu-Terph), with results being compared directly to Sigman's reagent Cu(phen)2 throughout (phen = 1,10-phenanthroline; DPQ = dipyridoquinoxaline; DPPZ = dipyridophenazine; Terph = terephthalate). Oxidative DNA damage was identified at the minor groove through use of surface bound recognition elements of methyl green, netropsin, and [Co(NH3)6]Cl3 that functioned to control complex accessibility at selected regions. ROS-specific scavengers and stabilizers were employed to identify the cleavage process, the results of which infer hydrogen peroxide produced metal-hydroxo or free hydroxyl radicals ((•)OH) as the predominant species. The extent of DNA damage owing to these radicals was then quantified through 8-oxo-2'-deoxyguanosine (8-oxo-dG) lesion detection under ELISA protocol with the overall trend following Cu-DPQ-Phen > Cu-Terph > Cu-Phen > Cu-DPPZ. Finally, the effects of oxidative damage on DNA replication processes were investigated using the polymerase chain reaction (PCR) where amplification of 120 base pair DNA sequences of varying base content were inhibited-particularly along A-T rich chains-through oxidative damage of template strands.
金属催化的活性氧物种 (ROS) 在生物系统中的有害影响可见于多种病理状况，包括癌症、心血管疾病、衰老和神经退行性疾病。然而另一方面，靶向核酸附近的 ROS 产生——如金属激活的博来霉素所证明的那样——为 ROS 活性化疗药物的开发铺平了道路。在此，我们报告了对铜(II) 发育治疗剂 Cu(DPQ)(phen) (Cu-DPQ-Phen)、Cu(DPPZ)(phen) (Cu-DPPZ-Phen) 和 {Cu(phen)2}2(μ-terph) (Cu-Terph) 的氧化核酶活性和氧化还原性质的机制研究，结果与 Sigman 试剂 Cu(phen)2 进行了直接比较（phen = 1,10-菲咯啉；DPQ = 二吡啶并喹喔啉；DPPZ = 二吡啶并吩嗪；Terph = 对苯二甲酸）。通过使用甲绿、萘啶和 [Co(NH3)6]Cl3 的表面结合识别元件，在小沟中鉴定到氧化 DNA 损伤，这些元件用于控制所选区域的复合物可及性。使用 ROS 特异性清除剂和稳定剂来确定裂解过程，结果推断过氧化氢产生的金属羟自由基或游离羟基自由基 ((•)OH) 是主要物种。通过 ELISA 方案中 8-氧代-2'-脱氧鸟苷 (8-oxo-dG) 损伤检测定量了这些自由基引起的 DNA 损伤程度，总体趋势为 Cu-DPQ-Phen > Cu-Terph > Cu-Phen > Cu-DPPZ。最后，通过聚合酶链反应 (PCR) 研究了氧化损伤对 DNA 复制过程的影响，其中不同碱基含量的 120 碱基对 DNA 序列的扩增受到模板链氧化损伤的抑制，特别是在富含 A-T 的链上。
