Huang Yue, Liu Yang, Dong Chuan, Zan Qi, Feng Feng, Wang Ruibing, Shuang Shaomin
College of Chemistry and Chemical Engineering & Institute of Environmental Science, Shanxi University, Taiyuan, 030006, PR China.
College of Chemistry and Chemical Engineering, Shanxi Datong University, Datong, 037009, PR China.
Biosens Bioelectron. 2025 May 15;276:117246. doi: 10.1016/j.bios.2025.117246. Epub 2025 Feb 7.
Mitophagy is a key pathway for regulating mitochondrial quality and quantity which is essential for the preservation of cellular homeostasis. Mitophagy process may be accompanied by changes of the mitochondrial microenvironments. The multifunctional fluorescent probe is crucial for the precise detection of multiple microenvironments, which is vital for the visualization of mitophagy. Herein, a mitochondria-immobilized fluorescent probe DPP was designed and fabricated to visualize mitophagy by monitoring polarity and viscosity in dual-channel. The DPP is characterized by "D-π-A″ structure, which provides the basis for the intramolecular charge transfer (ICT) and twisted intramolecular charge transfer (TICT) platform, enabling dual-channel responses to polarity and viscosity at emission wavelengths of 487 nm and 656 nm, respectively. The significant wavelength gap (169 nm) between the above channels prevents signal crosstalk. Additionally, the incorporation of 1, 4-dibenzyl chloride grants the probe mitochondrial immobilization capabilities, avoiding the leak of probe due to mitochondrial depolarization during autophagy. The DPP accumulates in mitochondria and monitors polarity and viscosity changes in green and red channels, respectively. Notably, the investigation of the relationship between polarity and viscosity revealed that an increase in viscosity is accompanied by a decrease in polarity. The mitophagy was effectively observed through the induction of DPP by rapamycin, with a particular emphasis on the increase in viscosity and decrease in polarity. Thus, DPP offers a powerful tool for a deeper understanding of the physiological and pathological processes associated with mitophagy and are regulated by various microenvironmental parameters.
线粒体自噬是调节线粒体质量和数量的关键途径，对维持细胞内稳态至关重要。线粒体自噬过程可能伴随着线粒体微环境的变化。多功能荧光探针对于精确检测多种微环境至关重要，这对线粒体自噬的可视化至关重要。在此，设计并制备了一种固定在线粒体上的荧光探针DPP，通过双通道监测极性和粘度来实现线粒体自噬的可视化。DPP具有“D-π-A”结构，为分子内电荷转移（ICT）和扭曲分子内电荷转移（TICT）平台提供了基础，分别在487 nm和656 nm发射波长下实现对极性和粘度的双通道响应。上述通道之间显著的波长差距（169 nm）可防止信号串扰。此外，1,4-二苄基氯的引入赋予了探针线粒体固定能力，避免了自噬过程中线粒体去极化导致的探针泄漏。DPP在线粒体中积累，分别在绿色通道和红色通道中监测极性和粘度变化。值得注意的是，对极性和粘度之间关系的研究表明，粘度增加伴随着极性降低。通过雷帕霉素诱导DPP有效观察到了线粒体自噬，特别强调了粘度增加和极性降低。因此，DPP为深入了解与线粒体自噬相关的生理和病理过程以及受各种微环境参数调节提供了有力工具。
