Electroacupuncture combined with neural stem cell transplantation promotes neurogenesis and functional recovery and is associated with tsRNA expression changes in a rat model of ischemic stroke.

Abstract

BACKGROUND: Electroacupuncture (EA) combined with neural stem cell transplantation (NSCT) represents a promising therapeutic strategy for neurological recovery after ischemic stroke. This study investigated the enhanced effects of EA at 'Quchi' (LI11) and 'Zusanli' (ST36) acupoints combined with NSCT on motor function and neurogenesis in a rat middle cerebral artery occlusion (MCAO) model, and explored the underlying tsRNA-associated molecular changes. METHODS: Neural stem cells (NSCs) were isolated from neonatal rats and characterized. MCAO rats were randomized into five groups: sham, MCAO, EA, NSCT, and EA+NSCT groups. Infarct volume was assessed via T2-weighted MRI, and neurological deficits were evaluated using modified Neurological Severity Scores (mNSS). Motor function was tested via open field and rotarod assays. Neurogenesis was analyzed by immunofluorescence co-staining for Brdu/DCX, Brdu/NeuN, and Brdu/GFAP. TsRNA expression profiles were examined by high-throughput sequencing, followed by bioinformatics analysis. The mRNA and protein levels of predicted target genes BDNF and Wnt1 were quantified by quantitative real-time polymerase chain reaction (qPCR) and Western blot. RESULTS: The EA+NSCT group showed a significantly reduced infarct volume compared with monotherapy groups (P&#x2009;<&#x2009;0.01), along with lower mNSS scores (P&#x2009;<&#x2009;0.05) and improved motor performance (P&#x2009;<&#x2009;0.001). Besides, EA+NSCT further promotes Brdu/GFAP and Brdu/NeuN expression in the peri-infarct cortex, surpassing either treatment alone. Preliminary TsRNA sequencing identified candidate tsRNAs, tRF-1:31-Gly-GCC-2-M2 and tRF-1:31-Gly-CCC-1-M2. The predicted target genes BDNF and Wnt1 were markedly upregulated at the protein level in all treatment groups, with the highest expression in the EA+NSCT group (P&#x2009;<&#x2009;0.01). CONCLUSION: Combined EA and NSCT significantly enhances neurogenesis and functional recovery after ischemic stroke, outperforming either intervention alone. These findings suggest that combined EA and NSCT may be associated with altered tsRNA expression and increased BDNF and Wnt1 levels, which may contribute to NSC differentiation and neural repair.