Xueshuantong injection combined with Salvianolate lyophilized injection improves the synaptic plasticity against focal cerebral ischemia/reperfusion injury in rats through PI3K/AKT/mTOR and RhoA/ROCK pathways

The combined use of two or more different drugs can better promote nerve recovery and its prognosis for treatment of stroke. Salvianolate lyophilized injection (SLI) made from the aqueous extraction of salvia miltiorrhiza and Xueshuantong injection (lyophilized) (XST) made from the Panax Notoginseng extraction are two herbal standardized preparations that have been widely used in China for the treatment of ischemic stroke. In this study, we investigated the neuroprotective effects of XST combined with SLI in the recovery stage of middle cerebral artery occlusion / reperfusion (MCAO/R) injury rat. Wistar rats were subjects to MCAO/R, then were treated with SLI or XST alone, or with their combination (1X1S) via tail injection daily for 14 days. The pathological status of the brain was detected by neurological deficit scores, TTC, regional cerebral blood flow and Nissl staining. Golgi-Cox staining was used to assess dendritic, axonal and synaptic remodeling. The expression of MAP-2, β-Tubulin, PSD95, SYN, BDNF and VEGF were analyzed by western blotting and immunofluorescence. The results showed that administration of 1X1S not only significantly decreased neurological scores and infarct volumes, but also increased regional cerebral blood flow, strengthened dendritic and synaptic remodeling compared with XST, SLI used alone. And the mechanism of combined of 1X1S to exert neuroprotection may be associated with PI3K/ AKT/ mTOR and RhoA/ROCK2 pathways. Overall, these findings suggest that combination of XST and SLI promotes dendritic spine density and synaptic plasticity via upregulation of the PI3K/ AKT/ mTOR pathways and inhabitation the RhoA/ROCK2 signaling pathway in rat with MCAO/R, showing its multiple-action-multiple-target efficacy and suggest a potential new strategy for ischemia.