Amelioration of cerebral ischemia–reperfusion injury based on liposomal drug delivery system with asialo-erythropoietin

Cerebral ischemia-reperfusion (I/R) injury induces secondary cerebral damage. As drugs for treating this type of injury have shown poor efficacy and adverse side effects in clinical trials, a novel therapeutic strategy has been long awaited. In this study, we focused on the disruption of the blood-brain barrier after stroke, and applied a liposomal drug delivery system (DDS) designed to enhance the pharmacological effect of the neuroprotectant and to avoid side effects. PEGylated liposomes were injected at varying time after the start of reperfusion in transient middle cerebral artery occlusion (t-MCAO) model rats. The results showed PEGylated liposomes accumulated in the ischemic hemisphere at an early stage after reperfusion and were retained in the lesion for at least 24h after injection. We also investigated the effectiveness of asialo-erythropoietin (AEPO)-modified PEGylated liposomes (AEPO-liposomes) in treating the cerebral I/R injury. AEPO-liposome treatment significantly reduced TTC-defined cerebral legion following cerebral I/R injury, and ameliorated motor function compared with vehicle and AEPO treatment. In conclusion, these results indicate that AEPO-liposomes are a promising liposomal formulation for protecting the brain from I/R injury, and that this liposomal DDS has potential as a novel strategy for the treatment of cerebral I/R injury.