A Reversible Fluorescent Probe for In Situ Monitoring Redox Imbalance during Mitophagy
Junbin Li, Lifei Song, Weiguo Hu, Qin Zuo, R. Li, Min Dai, Yibo Zhou, Zhihe Qing
Abstract
Mitophagy is the lysosome-dependent degradation of damaged and dysfunctional mitochondria, which is closely associated with H 2 O 2 -related redox imbalance and pathological processes. However, development of fast-responding and highly sensitive reversible fluorescent probes for monitoring of mitochondrial H 2 O 2 dynamics is still lacking. Herein, we report a reversible fluorescent probe ( M-HP ) that enables real-time imaging of H 2 O 2 -related redox imbalance. In vitro studies demonstrated that M-HP had a rapid response and high sensitivity to the H 2 O 2 /GSH redox cycle, with a detection limit of 17 nM for H 2 O 2 . M-HP was applied to imaging of H 2 O 2 fluctuation in living cells with excellent reversibility and mitochondrial targeting. M-HP reveals an increase in mitochondrial H 2 O 2 under lipopolysaccharide stimulation and a decrease in H 2 O 2 following the combined treatment with rapamycin. This suggests that the level of oxidative stress is significantly suppressed after the enhancement of mitophagy. The rationally designed M-HP offers a powerful tool for understanding redox imbalance during mitophagy.