ROS-responsive, brain- and M1 microglia-targeting modified ginkgetin-loaded smart liposomes ameliorate cerebral ischemia by HIF-1α-mediated negative regulation of microglia pyroptosis

Ischemic stroke triggers a cascade of mitochondrial dysfunction, oxidative stress, neuroinflammation, and pyroptosis, ultimately leading to neuronal injury and neurological deficits. Therapeutic efficacy is often limited by inadequate blood-brain barrier penetration and off-target effects. To address these challenges, we designed 3R@Lipo/Gink, a biocompatible liposomal formulation modified with an ROS-responsive TK polymer and two functional peptides-RVG29 for enhanced brain delivery and MG1 for microglia enrichment-to enable precise transport of ginkgetin, which has been demonstrated to exert neuroprotective effects through multiple potential mechanisms, to ischemic lesions. In a middle cerebral artery occlusion/reperfusion model, 3R@Lipo/Gink markedly reduced infarct size, alleviated neuronal injury, and improved motor performance. Single-cell RNA sequencing and in vitro co-culture experiments identified microglia and neurons as the primary responsive cell types. Mechanistic studies showed that 3R@Lipo/Gink suppressed HIF-1α expression, thereby downregulating c-Myc-mediated microglial proliferation and attenuating NLRP3-dependent pyroptosis. These protective effects were reversed by FG-4592, a prolyl hydroxylase inhibitor that stabilizes HIF-1α, supporting the involvement of the HIF-1α pathway. Through mitigating microglial overactivation and interrupting the inflammatory-pyroptotic loop, 3R@Lipo/Gink ultimately remodels the microglia-mediated inflammatory microenvironment around neurons and improves functional recovery. These findings highlight 3R@Lipo/Gink as a promising targeted nanotherapeutic strategy for ischemic stroke and other nervous system diseases.