Targeting ALOX12: design, synthesis, and anti-inflammatory mechanism study of linker-free PROTAC molecules

Acute pancreatitis (AP) is a life-threatening disorder with no specific anti-inflammatory treatments available. 12-lipoxygenase (ALOX12) acts as a key regulator of inflammation and pyroptosis during AP progression. In this study, we established an LPS-induced inflammatory model in AR42J cells and confirmed that ALOX12 strongly aggravates AP-associated inflammation and pyroptosis. The ALOX12-targeted compound MH-04 was identified via virtual screening, with an IC₅₀ value of 0.72 μM. We further synthesized eight novel PROTAC molecules using linker-free PROTAC technology. Among these candidates, MH-06 was found to specifically target and effectively degrade ALOX12 protein. Mechanistic assays revealed that MH-06 dose-dependently decreases reactive oxygen species (ROS) production, restores mitochondrial function, inhibits the MAPK signaling pathway and modulates macrophage polarization, thereby lowering the release of pro-inflammatory cytokines. In the cerulein-induced AP mouse model, MH-06 exerted remarkable therapeutic and preventive effects. Collectively, this work offers new perspectives and promising chemical entities for the development of targeted therapies against AP. Given its favorable pharmacological profiles, MH-06 merits further detailed investigation.