Development of Improved Spin Probes for Aging Research

描述（由申请人提供）：目前需要改进的自旋探针，以帮助对活性氧（ROS）介导的疾病进行诊断和基础研究。对于年龄相关疾病的研究尤其如此，因为氧化损伤在衰老过程中积累，并且许多年龄相关疾病如帕金森病和阿尔茨海默病的特征在于过量ROS的损伤。自旋探针允许使用各种磁共振技术（例如电子顺磁共振（EPR））来检测和鉴定这些不稳定的氧物质。虽然动物中的某些癌症（Mikuni等人，2004）和组织，如分离的大鼠心脏（Zweier等人，1998），已经使用EPR成像（EPRI）成功地成像，但是使用当前一代的自旋探针，不可能检测年龄相关疾病中ROS的产生。开发新的自旋探针，允许在体内检测由帕金森氏症和其他ROS疾病产生的ROS，将代表诊断这些疾病和指导其治疗的重大进展。为了克服目前的自旋探针化合物的局限性，我们建议调查自旋探针基于单个顺磁性氮原子封装在C60富勒烯，N@C60。在这个物种中，氮被钉在对称富勒烯笼的中心，在那里它的未成对自旋完全被保护不与外部物种反应。富勒烯笼中与外部环境的隔离赋予N@C60最已知的EPR线宽之一（Morton等人，2006），使其检测效率比目前的化合物高100至1000倍。在N@C60表面上发生的ROS反应将在光谱中产生可测量的位移。这些综合特性使N@C60成为理想的自旋探针。鉴于其高潜力，使一个近乎完美的自旋探针，该项目的目的是合成和表征自旋探针的基础上N@C60的分子氧，超氧化物，和其他生物学上重要的活性氧物种。该第一阶段项目的具体目标是：1）首先确定有可能以足够的数量生产我们的候选自旋探针，2）显示我们的N@C60衍生物具有适合用作自旋探针的EPR信号，以及3）提供初步数据以与当前可用的自旋探针进行比较，包括超氧化物的检测。 许多与年龄相关的疾病，如帕金森氏病和阿尔茨海默氏病的特征在于来自过量活性氧（ROS）的损伤，并且使用当前的成像技术不可能非侵入性地检测人体内ROS的产生。自旋探针是设计用于与活性氧（ROS）反应的分子试剂，这使得它们能够使用各种磁共振技术被检测和识别。为了克服目前的代理商的局限性，使更好的成像技术的ROS疾病的发展，我们建议调查基于顺磁性氮原子封装在C60富勒烯，N@C60的新型自旋探针。开发新的自旋探针，允许在体内检测由帕金森氏症和其他ROS疾病产生的ROS，将代表诊断这些疾病和指导其治疗的重大进展。

DESCRIPTION (provided by applicant): There is currently a need for improved spin probes to help with the diagnosis of and fundamental research into diseases mediated by reactive oxygen species (ROS). This is especially true for the study of age related diseases, since oxidative damage accumulates during the aging process, and many age related disorders such as Parkinson's and Alzheimer's disease are characterized by damage from excess ROS. Spin probes allow these unstable oxygen species to be detected and identified using various magnetic resonance techniques, such as electron paramagnetic resonance (EPR). While certain cancers in animals (Mikuni et al., 2004) and tissues, such as an isolated rat heart (Zweier et al., 1998), have been successfully imaged using EPR imaging, (EPRI), with the current generation of spin probes it is not possible to detect the generation of ROS in age related disorders. The development of new spin probes that allow in vivo detection of ROS produced by Parkinson's and other ROS diseases would represent a significant advance for diagnosing these conditions and for guiding their treatment. To overcome limitations of current spin probe compounds, we propose to investigate spin probes based upon single paramagnetic nitrogen atoms encapsulated in C60 fullerenes, N@C60. In this species, the nitrogen is pinned at the center of the symmetric fullerene cage where its unpaired spins are completely protected from reaction with external species. Isolation from the outside environment in the fullerene cage endows N@C60 with one of the narrowest known EPR line widths, (Morton et al., 2006), giving it a detection efficiency 100 to 1000 times better than the current compounds. Reactions of ROS occurring on the surface N@C60 will produce measurable shifts in the spectrum. These combined features make N@C60 the ideal spin probe. Given its high potential to make a nearly perfect spin probe, the aim of this project is to synthesize and characterize a spin probe based on N@C60 for molecular oxygen, superoxide, and other biologically important reactive oxygen species. The specific aims of this phase I project are: 1) First establish that it is possible to produce our candidate spin probe in quantities sufficient for testing, 2) Show that our N@C60 derivative has an EPR signal suitable for use as a spin probe, and 3) Provide preliminary data for comparison with currently available spin probes, including the detection of superoxide. Many age related disorders such as Parkinson's and Alzheimer's disease are characterized by damage from excess reactive oxygen species (ROS), and it is not possible with the current imaging technology to non-invasively detect the generation of ROS in people. Spin probes are molecular agents designed to react with reactive oxygen species (ROS) which enables them to be detected and identified using various magnetic resonance techniques. To overcome the limitations of current agents and enable the development of better imaging techniques for ROS disorders, we propose to investigate new types of spin probes based upon paramagnetic nitrogen atoms encapsulated in C60 fullerenes, N@C60. The development of new spin probes that allow in vivo detection of ROS produced by Parkinson's and other ROS diseases would represent a significant advance for diagnosing these conditions and for guiding their treatment.