Light‐Controlled Modulation of 15‐Lipoxygenase‐1 Regulates Intestinal Inflammatory Signaling
Anastasia Louka, Eirini‐Eleni Kalaitzaki, Athanasios Panousis, Sotirios Bonoras, Charalampos Livas, George Froudakis, Ioannis Drygiannakis, Athina Damianaki, George Kolios, Vassilis Valatas, Nikolaos EleftheriadisABSTRACT
Photopharmacology offers powerful opportunities for the spatiotemporal control of biological processes, yet the rational design of photoswitchable enzyme inhibitors remains challenging. Here, we report a target‐guided strategy for the development of diazo‐based photoswitchable inhibitors of human 15‐lipoxygenase‐1 (15‐LOX‐1), a key enzyme in inflammatory signaling, ferroptosis, and cancer. Guided by the structural features of known ligands, we developed three complementary photoswitch classes: reversible azobenzenes (ABs), azo‐heteroarenes (HAs), and covalent azo‐bis‐alkynes (BAs). These compounds exhibit efficient E / Z photoisomerization and high bistability, supported by single‐crystal x‐ray diffraction and density functional theory calculations. Enzymatic inhibitory and kinetic studies revealed distinct activity and selectivity profiles within the tested substrates/isoenzyme: AB and HA derivatives function as E ‐ON/Z‐OFF inhibitors, whereas BA derivatives display Z ‐ON/ E ‐OFF behavior, enabling programmable light‐controlled modulation. We validated 15‐LOX‐1 as a therapeutic target in cellular and in vivo mouse models of colonic inflammation, where inhibition suppressed IL‐8 expression. Finally, using our reversible and covalent photoswitches, we demonstrate photoisomer‐dependent suppression of IL‐8. Beyond 15‐LOX‐1, this work establishes a generalizable framework for the rational development of selective photoswitchable inhibitors with tunable biological outcomes.