Subacute intranasal oxytocin improves neurological recovery after ischemic stroke

Abstract

Oxytocin (OXT) is a neuropeptide known for its anti-inflammatory and neuroprotective properties; however, its role in post-stroke recovery remains poorly defined. In this study, we investigated whether intranasal OXT administration during the subacute phase of stroke improves neurological outcomes and modulates microglial responses. Male mice underwent permanent middle cerebral artery occlusion and received intranasal OXT (300 ng/g) or saline on days 3 and 5 post-stroke. Neurological function was assessed using the modified neurological severity score; infarct volume was evaluated through hematoxylin-eosin (HE) staining, and survival rates were monitored until day 7. Immunofluorescence was used to assess microglial polarization in the peri-infarct region. OXT-treated mice showed significantly greater functional improvement and higher survival rates than saline-treated controls. Infarct volume was significantly reduced, and microglial polarization was altered by OXT, with a decrease in pro-inflammatory M1-type markers and an increase in anti-inflammatory M2-type markers. These findings demonstrate that OXT promotes neurological recovery through anti-inflammatory and neuroprotective mechanisms. Given its feasibility as a non-invasive delivery method, intranasal OXT may offer a promising therapeutic approach to enhance post-stroke neurorepair.