Nanoliposomes Reduce Stroke Injury Following Middle Cerebral Artery Occlusion in Mice

Abstract

Neuroprotective strategies for stroke remain inadequate. Nanoliposomes comprised of phos-phatidylcholine, cholesterol and monosialogangliosides (NL) induced an antioxidant protective response in endothelial cells exposed to amyloid insults. We tested the hypotheses that NL will preserve SH-SY5Y neuroblastoma cell viability following hypoxic injury and will reduce injury in mice following middle cerebral artery occlusion (MCAO). Neuroblastoma were exposed to 20-hour physoxic (5% oxygen) or hypoxic (1% oxygen) condition without or with NL (100 or 300 µg/mL). Viability was measured using calcein-AM fluorescence and SH-SY5Y gene expression of antioxidant proteins heme oxygenase-1 (HO-1), NAD(P)H quinone dehydrogenase 1 (NQO1) and superoxide dismutase 1 (SOD1) were measured by quantitative polymerase chain reaction. C57BL/6J mice were treated with saline (N=8) or NL (10000 ug/mL, N=7) while undergoing 60-minute MCAO followed by reperfusion. Day 2 post-injury neurologic impairment score and infarction size were compared. Neuroblastoma showed reduced viability following hypoxia that was reversed by NL. NL increased gene expression of HO-1, NQO1 and SOD1 versus controls. NL-treated mice showed reduced neurologic impairment and brain infarct size (18.8±2% versus 27.3±2.3%, p=0.017) versus controls. NL reduced stroke injury in mice subjected to MCAO likely through induction of an antioxidant stress response. NL is a candidate novel agent for stroke.