Bifunctional Fluorescent Probe for Simultaneous Imaging of H ₂ S and Hcy Crosstalk and Therapeutic Evaluation in Acute Kidney Injury

Acute kidney injury (AKI) is a critical clinical condition characterized by the rapid loss of renal function, requiring timely detection and intervention. Hydrogen sulfide (H₂S) and homocysteine (Hcy) have been identified as key biomarkers in AKI, yet their dynamic interplay and coordinated regulation remain elusive. Herein, we report a bifunctional fluorescent probe (<b>Probe 1</b>), based on coumarin derivatives, capable of real-time, simultaneous imaging of H₂S and Hcy in distinct fluorescence channels with high sensitivity, selectivity, and rapid response. <b>Probe 1</b> enables the concurrent detection of H₂S and Hcy and was successfully applied to visualize both endogenous and exogenous levels in living cells. Notably, this probe achieved the first dual-channel imaging of H₂S and Hcy fluctuations in cisplatin-induced AKI models, both in vitro and in vivo. Furthermore, it was employed to evaluate therapeutic responses to AKI-related drug treatments, demonstrating its value for dynamic monitoring of disease progression and intervention efficacy. This study presents the first chemical tool for investigating the synergistic roles of H₂S and Hcy in AKI, offering new insights into sulfur-based signaling pathways and providing a promising platform for early diagnosis and therapeutic evaluation in AKI.