Acupuncture promotes post-stroke angiogenesis and neuroprotection through regulation of the DLL4/Notch1 signaling pathway.

OBJECTIVES: Acupuncture, a core component of traditional Chinese medicine, is widely used for treating ischemic stroke; however, its neuroprotective mechanisms remain unclear. This study investigated the pro-angiogenic and neuroprotective effects of acupuncture following ischemic stroke and examined the potential involvement of DLL4/Notch1 signaling in these processes. METHODS: , acupuncture serum was evaluated as a modulatory factor in BMSC endothelial differentiation and was found to enhance cellular responsiveness to VEGFA165 and bFGF rather than acting as an independent angiogenic inducer, while DLL4 overexpression and knockdown were used to clarify its role in angiogenesis. In PC12 OGD/R cells, DLL4 plasmid transfection assessed viability (CCK-8), apoptosis (Hoechst and Annexin V/PI), and network-like phenotypes, along with Notch1/Hes1/Hes5, HIF-1α, and VEGF pathway analysis. RESULTS: Acupuncture improved survival, motor function, and body weight, reduced infarct size, and increased microvascular density, associated with HIF-1α downregulation and DLL4, Notch1, and VEGF upregulation. Acupuncture serum alone had limited instructive capacity for endothelial differentiation, but acted permissively to enhance BMSC responsiveness to VEGFA165 and bFGF, resulting in improved differentiation-associated marker expression and tube formation. DLL4 overexpression enhanced vascular integrity, while knockdown reversed these effects. In PC12 OGD/R cells, DLL4 overexpression reduced apoptosis, improved viability, and enhanced network-like phenotypes, accompanied by increased Notch1/Hes1/Hes5 and VEGF expression and reduced HIF-1α expression. CONCLUSIONS: Acupuncture facilitates angiogenesis and neurofunctional recovery after ischemic stroke, with DLL4/Notch1-associated regulatory responses potentially contributing to these effects. DLL4 upregulation may further enhance angiogenic and neuroprotective outcomes, suggesting that DLL4 may represent a potential therapeutic target in acupuncture-mediated post-stroke repair.