The broad spectrum mixed-lineage kinase 3 inhibitor URMC-099 prevents acute microgliosis and cognitive decline in a mouse model of perioperative neurocognitive disorders

Perioperative neurocognitive disorders (PND), including delirium and postoperative cognitive dysfunction, are serious complications that afflict up to 50% of surgical patients and for which there are no disease-modifying therapeutic options. Here, we test whether prophylactic treatment with the broad spectrum mixed-lineage kinase 3 inhibitor URMC-099 prevents surgery-induced neuroinflammation and cognitive impairment in a translational model of orthopedic surgery-induced PND. We used a combination of two-photon scanning laser microscopy and CLARITY with light-sheet microscopy to define surgery-induced changes in microglial dynamics and morphology. Orthopedic surgery induced widespread microglial activation in the hippocampus and cortex that accompanied impairments in episodic memory. URMC-099 prophylaxis prevented these neuropathological sequelae without impacting bone fracture healing. Together, these findings provide compelling evidence for the advancement of URMC-099 as a therapeutic option for PND.