Wang Jiang-Lin, Zhang Lu, He Huan, Zhang Pengfei, Jiang Feng-Lei
Guangdong Key Laboratory of Nanomedicine, CAS-HK Joint Lab of Biomaterials, CAS Key Laboratory of Biomedical Imaging Science and System, Shenzhen Engineering Laboratory of Nanomedicine and Nanoformulations, Shenzhen Key Laboratory of Metabolic Health, Shenzhen Metabolism and Reproductive Targeted Delivery Proof-of-Concept Center, CAS Key Lab for Health Informatics, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, P. R. China.
Non-Power Nuclear Technology Collaborative Innovation Center, School of Nuclear Technology and Chemistry & Biology, Hubei University of Science and Technology, Xianning 437100, P. R. China.
ACS Sens. 2025 Sep 26;10(9):6828-6839. doi: 10.1021/acssensors.5c01636. Epub 2025 Aug 17.
Mitochondrial membrane potential (ΔΨ) is a critical regulator of cellular homeostasis and an established biomarker in mitochondrial dysfunction. While super-resolution fluorescence imaging reveals intrinsic links between mitochondrial ultrastructure and function, prolonged monitoring of the dynamic ΔΨ remains constrained by the scarcity of photostable voltage-sensitive probes. Here, we designed and synthesized three water-soluble near-infrared boron dipyrromethene (BODIPY) probes (). These cationic pyridinium-functionalized probes exhibit specific mitochondria localization (Pearson's colocalization coefficient >0.93), high photostability (<15% intensity loss after 15 min laser irradiation), and exceptional biocompatibility. When integrated with structured illumination microscopy (SIM), they resolved mitochondrial cristae ultrastructure at 0.24 μm resolution and captured real-time ΔΨ fluctuations during fusion/fission (∼15 mV shifts) and mitochondria-lysosome contact (MLC). Semiquantitative submitochondrial models further revealed voltage gradients (150-170 mV) across cristae junctions, challenging the classical "homogeneous ΔΨ" paradigm. The probes' compatibility with multiplexed imaging enabled continuous ΔΨ tracking during mitophagy, uncovering transient bioenergetic hotspots. This work bridges nanoscale mitochondrial dynamics to disease mechanisms, providing tools to dissect pathologies from neurodegeneration to cancer.
线粒体膜电位（ΔΨ）是细胞稳态的关键调节因子，也是线粒体功能障碍中已确立的生物标志物。虽然超分辨率荧光成像揭示了线粒体超微结构与功能之间的内在联系，但由于光稳定电压敏感探针的稀缺，对动态ΔΨ的长期监测仍然受到限制。在此，我们设计并合成了三种水溶性近红外硼二吡咯亚甲基（BODIPY）探针（）。这些阳离子吡啶功能化探针表现出特定的线粒体定位（皮尔逊共定位系数>0.93）、高光稳定性（激光照射15分钟后强度损失<15%）和出色的生物相容性。当与结构照明显微镜（SIM）结合时，它们以0.24μm的分辨率解析了线粒体嵴超微结构，并捕捉了融合/裂变（约15mV变化）和线粒体-溶酶体接触（MLC）过程中的实时ΔΨ波动。半定量亚线粒体模型进一步揭示了嵴连接处的电压梯度（150-170mV），挑战了经典的“均匀ΔΨ”范式。这些探针与多重成像的兼容性使得在细胞自噬过程中能够持续跟踪ΔΨ，揭示了瞬态生物能量热点。这项工作将纳米级线粒体动力学与疾病机制联系起来，提供了从神经退行性疾病到癌症剖析病理的工具。
