靶向线粒体的BODIPY类近红外荧光探针的构建及在活性氮物种检测方面的应用

Mitochondria, which are the major source of intracellular reactive nitrogen species (RNS: NO, ONOO-, HNO), play a significant role in the eukaryotic cells. As the signal carriers, mitochondrial RNS may participate in various biochemical events in mitochondria. Hence, visualization of RNS on mitochondria is of important biological significance. Several mitochondrial targeting fluorescent probes developed so far are insufficient in view of water solubility, anti-background interference, photo-stability, and signal-noise ratio. BODIPY core which is known be photo-stable and highly fluorescent is going to be used as the key scaffold. Pyridinium salts will be installed onto BODIPYs using an innovative synthetic method developed by us to improve water solubility, to afford mitochondrial targeting ability, as well as to favor NIR response. After introduction of RNS responsive functionality into BODIPYs, the response to RNS and sub-cellular localization will be systemically investigated. The structure-activity relationship will be worked out and further optimization will be explored to develop novel mitochondrial targeting and RNS responsive NIR fluorescent probes which should possess high signal-noise ration and excellent photo-stability. Such a study will be significant for the understanding the bio-function of RNS, the mechanism of pathogenesis and treatment.

线粒体是细胞中非常重要的细胞器，线粒体内存在的多种活性氮物种（RNS: NO, ONOO-, HNO）作为信号载体参与线粒体内的生物化学反应，可视化追踪线粒体内活性氮化物具有十分重要的生物学意义。当前具备线粒体靶向功能的活性氮物种荧光探针种类有限，在水溶性、抗背景干扰、光稳定性、信噪比等方面仍有不足之处。本项目选取光稳定性好，荧光效率高的BODIPY类染料为骨架，采用创新合成方法制备吡啶季铵盐取代BODIPY类荧光染料，既改善水溶性，又靶向线粒体，且有利于近红外响应。引入RNS响应基团，系统研究对活性氮物种的响应能力及定位效果；通过构效关系研究，筛选构建水溶性好、信噪比高、光稳定性强、具备近红外波长和线粒体靶向功能的活性氮物种荧光探针，为揭示活性氮物种的生物功能，促进对相关疾病发病机制与治疗机制的认识提供新的技术手段。

线粒体是细胞中非常重要的细胞器，线粒体内存在的多种活性物种作为信号载体参与线粒体内的生物化学反应，可视化追踪线粒体内活性物种具有十分重要的生物学意义。本课题围绕靶向线粒体的BODIPY类近红外荧光染料和探针的构建及应用研究，开发了吡咯合成新方法，构建了二十多个吡啶/吡啶季铵盐取代BODIPY染料，研究其对线粒体靶向能力的影响。本项目基于BODIPY和吡啶季铵盐取代BODIPY染料构建了检测活性氮物种、活性氧物种、活性硫物种和金属离子的荧光探针。得到的染料与探针不仅成功的应用于生物成像，还研究了部分活性物质在体内的浓度变化与炎症和肝损伤之间的关系。其中检测ONOO‒探针在药物性肝损伤程度研究、药物性肝损伤机制研究、药物安全评价等方面具有广阔的应用前景。其它探针为研究生物活性物种在机体中生理和病理的作用提供了灵敏有效的检测手段。