Abstract
Although electroacupuncture (EA) has been shown to be effective in the treatment of stroke, its mechanisms of action remain undefined. This study explored the therapeutic effects of EA in rats with cerebral ischemia-reperfusion injury (CIRI) and evaluated its possible mechanisms in promoting angiogenesis. To evaluate the effect of EA, we used 2, 3, 5-Triphenyl-2H-Tetrazolium Chloride (TTC) staining and behavior score to calculate the cerebral infarct volume and neurological deficit score after CIRI. Western blot (WB) analysis was employed to evaluate the expression of cluster of differentiation 34 (CD34), erythropoietin (EPO), vascular endothelial growth factor (VEGF) and phospho-Src (p-Src) in the brain of the rats with CIRI. On the other hand, we established an oxygen-glucose deprivation/reoxygenation (OGD/R) injury model using brain microvascular endothelial cells (BMECs), and analyzed cell viability and expression of VEGF or p-Src using cell counting kit-8 (CCK-8) and WB, respectively. Our data showed that EA at the GV26 acupoint could significantly promote the expression of CD34, EPO, VEGF and p-Src in CIRI rats. Our CCK-8 results demonstrated that intervention with recombinant EPO and VEGF proteins remarkably improved the viability of BMECs after OGD/R, while a Src inhibitor, PP1, reversed this phenotype. The WB results showed that the recombinant EPO protein increased the expression of VEGF and p-Src, which was significantly inhibited by PP1. Taken together, our findings showed that EA at the GV26 acupoint can significantly attenuate ischemic injury after stroke and promote angiogenesis via activation of EPO-mediated Src and VEGF signaling pathways. Besides, the upregulation of VEGF may also be associated with the activation of Src by EPO.