Electroacupuncture Improves Microglial Polarization Induced-Inflammation by Regulating the TGF-β/Smad-3 Signaling Pathway in Ischemic Stroke Mice

Abstract

Aims: This study aimed to investigate the mechanisms underlying the therapeutic effects of electroacupuncture (EA) at the Dazhui (GV14) and Baihui (GV20) acupoints in the treatment of ischemic stroke (IS). Methods and Results: The therapeutic efficacy of EA was evaluated using a middle cerebral artery occlusion (MCAO) mouse model. Neurological function was assessed through behavioral assessments, and infarct volume was measured using magnetic resonance imaging. Techniques such as immunofluorescence and western blotting were employed to analyze neural injury recovery, neuroinflammation, microglia/macrophage activation and polarization, as well as alterations in the TGF-β/Smad3 signaling pathway. Our findings demonstrated that EA significantly improved neurological function and reduced infarct volume in MCAO mice. Furthermore, EA attenuated neuroinflammation by suppressing the polarization of microglia toward the pro-inflammatory M1 phenotype. Additionally, EA decreased the expression of TGF-β and Smad3 proteins following MCAO. Conclusion: EA may inhibit the M1 polarization of microglia/macrophages and provide a protective effect against ischemic brain injury by modulating the TGF-β/Smad-3 signaling pathway. These findings suggest that EA could be a potential therapeutic strategy for IS treatment.