Discovery of a novel AhR–CYP1A1 axis activator for mitigating inflammatory diseases using an in situ functional imaging assay
Zhang Feng, Bei Zhao, Yufan Fan, Lanhui Qin, Jinhui Shi, Lin Chen, Lang Xu, Xudong Jin, Mengru Sun, Hong‐Ping Deng, Hairong Zeng, Zhangping Xiao, Xin Yang, Guangbo Ge
Abstract
The aryl hydrocarbon receptor (AhR) plays a crucial role in regulating many physiological processes. Activating the AhR–CYP1A1 axis has emerged as a novel therapeutic strategy against various inflammatory diseases. Here, a practical in situ cell-based fluorometric assay was constructed to screen AhR-CYP1A1 axis modulators, via functional sensing of CYP1A1 activities in live cells. Firstly, a cell-permeable, isoform-specific enzyme-activable fluorogenic substrate for CYP1A1 was rationally constructed for in-situ visualizing the dynamic changes of CYP1A1 function in living systems, which was subsequently used for discovering the efficacious modulators of the AhR–CYP1A1 axis. Following screening of a compound library, LAC-7 was identified as an efficacious activator of the AhR–CYP1A1 axis, which dose-dependently up-regulated the expression levels of both CYP1A1 and AhR in multiple cell lines. LAC-7 also suppressed macrophage M1 polarization and reduced the levels of inflammatory factors in LPS-induced bone marrow-derived macrophages. Animal tests showed that LAC-7 could significantly mitigate DSS-induced ulcerative colitis and LPS-induced acute lung injury in mice, and markedly reduced the levels of multiple inflammatory factors. Collectively, an optimized fluorometric cell-based assay was devised for in situ functional imaging of CYP1A1 activities in living systems, which strongly facilitated the discovery of efficacious modulators of the AhR–CYP1A1 axis as novel anti-inflammatory agents. An optimized fluorometric cell-based assay was devised for in situ functional imaging of CYP1A1 activities in living systems, which was used for discovering efficacious AhR–CYP1A1 axis activators as novel anti-inflammatory agents.