Protective effect of Alisol A on cerebral ischemia-reperfusion induced neurovascular unit dysfunction by activating AKT/GSK3β pathway in vivo

Background: Neurovascular unit (NVU) dysfunction is a major process in the pathophysiological process of cerebral ischemia-reperfusion (CI/R). Our previous studies have confirmed that the main active ingredient of Alisma orientale exhibits protective effect on CI/R injury. Therefore, this study is designed to verify whether Alisol A, one of the main active components of Alisma, attenuates CI/R-induced NVU dysfunction through activation of AKT/GSK3β pathway. Methods C57BL/6J mice were used to establish the animal model of global cerebral ischemia- reperfusion (GCI/R) and treated with Alisol A and GSK690693 (an AKT inhibitor). We carried out modified neurological severity score (mNSS) and morris water maze (MWM) to test learning and memory abilities. Nissl staining and CD31, GFAP, Iba1, NeuN immunostaining were performed to determine morphological and quantitative changes in neuronal and endothelial cells, as well as overactivation of astrocytes and microglia. Ultrastructure changes of NVU were observed by transmission electron microscope (TEM). Expression of IL-6, IL-1β, BAX, Bcl-2 and AKT/GSK3βwere detected by enzyme-linked immunosorbent assay (ELISA) and western blot. The alterations in neuronal/glial metabolism were measured using magnetic resonance spectroscopy (MRS). Results The data showed that Alisol A treatment significantly improved neurological deficits and memory loss caused by GCI/R in C57BL/6J mice. Furthermore, Alisol A administration effectively suppressed the disruption of neurons and endothelial cells, activation of astrocytes and microglia, cell apoptosis and release of inflammatory factors in GCI/R-induced C57BL/6J mice, which were reversed by GSK690693. Conclusions Alisol A significantly alleviated NVU damage caused by GCI/R via activation of AKT/GSK3β, suggesting that Alisol A maybe a promising medicine for the treatment of GCI/R.