Suppression of DAPK1 reduces ischemic brain injury through inhibiting cell death signaling and promoting neural remodeling

The role of death-associated protein kinase1 (DAPK1) in post-stroke functional recovery is controversial, as is its mechanism of action and any neural remodeling effect after ischemia. To assess the debatable role of DAPK1, we established the middle cerebral artery occlusion (MCAo) model in DAPK1 knockout mice and Sprague-Dawley (SD) rats. We identified that the genetic deletion of the DAPK1 as well as pharmacological inhibition of DAPK1 showed reduced brain infarct volume and neurological deficit. We report that DAPK1 inhibition (DI) reduces post-stroke neuronal death by inhibiting BAX/BCL2 and LC3/Beclin1 mediated apoptosis and autophagy, respectively. Histological analysis displayed a reduction in nuclear condensation, neuronal dissociation, and degraded cytoplasm in the DI group. The DI treatment showed enhanced dendrite spine density and neurite outgrowth, upregulated neural proliferation marker proteins like brain-derived neurotrophic factor, and reduced structural abnormalities of the cortical pyramidal neurons. This research shows that DAPK1 drives cell death, its activation exacerbates functional recovery after cerebral ischemia and shows that oxazolone-based DI could be an excellent candidate for stroke and ischemic injury intervention.