Electroacupuncture alters brain network functional connectivity in subacute stroke: A randomised crossover trial.

BACKGROUND: Electroacupuncture (EA) is a promising rehabilitation treatment for upper-limb motor recovery in stroke patients. However, the neurophysiological mechanisms underlying its clinical efficacy remain unclear. This study aimed to explore the immediate modulatory effects of EA on brain network functional connectivity and topological properties. METHODS: The randomized, single-blinded, self-controlled two-period crossover trial was conducted among 52 patients with subacute subcortical stroke. These patients were randomly allocated to receive either EA as the initial intervention or sham electroacupuncture (SEA) as the initial intervention. After a washout period of 24 hours, participants underwent the alternate intervention (SEA or EA). Resting state electroencephalography signals were recorded synchronously throughout both phases of the intervention. The functional connectivity (FC) of the parietofrontal network and small-world (SW) property indices of the whole-brain network were compared across the entire course of the two interventions. RESULTS: The results demonstrated that EA significantly altered ipsilesional parietofrontal network connectivity in the alpha and beta bands (alpha: F = 5.05, P = .011; beta: F = 3.295, P = .047), whereas no significant changes were observed in the SEA group. When comparing between groups, EA significantly downregulated ipsilesional parietofrontal network connectivity in both the alpha and beta bands during stimulation (alpha: t = -1.998, P = .049; beta: t = -2.342, P = .022). Significant differences were also observed in the main effects of time and the group × time interaction for the SW index (time: F = 5.516, P = .026; group × time: F = 6.892, P = .01). In terms of between-group comparisons, the EA group exhibited a significantly higher SW index than the SEA group at the post-stimulation stage (t = 2.379, P = .018). CONCLUSION: These findings suggest that EA downregulates ipsilesional parietofrontal network connectivity and enhances SW properties, providing a potential neurophysiological mechanism for facilitating motor performance in stroke patients.

Electroencephalography-based parietofrontal connectivity modulated by electroacupuncture for predicting upper limb motor recovery in subacute stroke.

BACKGROUND: Predicting motor recovery in stroke patients is essential for effective rehabilitation planning and goal setting. However, intervention-specific biomarkers for such predictions are limited. This study investigates the potential of electroacupuncture (EA) - induced brain network connectivity as a prognostic biomarker for upper limb motor recovery in stroke. METHODS: A randomized crossover and prospective observational study was conducted involving 40 stroke patients within 30 days of onset. Patients underwent both EA and sham electroacupuncture (SEA) interventions. Simultaneously, resting electroencephalography signals were recorded to assess brain response. Patients' motor function was monitored for 3 months and categorized into Poor and proportional (Prop) recovery groups. The correlations between the targeted brain network of parietofrontal (PF) functional connectivity (FC) during the different courses of the 2 EA interventions and partial least squares regression models were constructed to predict upper limb motor recovery. RESULTS: Before the EA intervention, only ipsilesional PF network FC in the beta band correlated with motor recovery (r = -0.37, P = .041). Post-EA intervention, significant correlations with motor recovery were found in the beta band of the contralesional PF network FC (r = -0.43, P = .018) and the delta and theta bands of the ipsilesional PF network FC (delta: r = -0.59, P = .0004; theta: r = -0.45, P = .0157). No significant correlations were observed for the SEA intervention (all P > .05). Specifically, the delta band ipsilesional PF network FC after EA stimulation significantly differed between Poor and Prop groups (t = 3.474, P = .002, Cohen's d = 1.287, Poor > Prop). Moreover, the partial least squares regression model fitted after EA stimulation exhibited high explanatory power (R2 = 0.613), predictive value (Q2 = 0.547), and the lowest root mean square error (RMSE = 0.192) for predicting upper limb proportional recovery compared to SEA. CONCLUSION: EA-induced PF network FC holds potential as a robust prognostic biomarker for upper limb motor recovery, providing valuable insights for clinical decision-making.

[Effect of electroacupuncture of different acupoints on the excitability of detrusor muscle and the expression of BDNF and TrkB in the spinal cord of rats with urinary retention due to spinal cord injury].

OBJECTIVE: To observe the effect of electroacupuncture (EA) of different acupoints on the expression of brain-derived neurotrophic factor (BDNF) and tropomyosine receptor kinase B (TrkB) in the spinal cord and the excitability of detrusor muscle of the uninary bladder in rats with urinary retention owing to spinal cord injury (SCI). METHODS: A total of 100 female SD rats were randomly divided into normal, sham-operation (sham), model, EA-Guanyuan (CV 4), and EA-Shuidao (ST 28) groups, with 20 cases in each. SCI induced urinary retention model was established by using weight dropping method. EA (1 mA, 2 Hz/15 Hz) was applied to "Guanyuan" (CV 4) and "Shuidao" (ST 28) respectively for 20 min, once a day for 10 days. The excitability (tone, contraction frequency) of the detrusor muscle of the bladder was detected in vitro by using electrophysiological method, and the expression of BDNF and TrkB in spinal cord was determined by immunohistochemistry staining. RESULTS: In comparison with normal control and sham groups, the tension and the contraction frequency of detrusor muscle in model group lowered significantly (P<0.05), while compared with model group, both the tension and contraction frequency of detrusor muscle increased pronouncedly in EA-CV 4 and EA-ST 28 groups (P<0.05), and the effect of EA-CV 4 was apparently superior to that of EA-ST 28 (P<0.05). In comparison with normal and sham groups, the BDNF and TrkB immunoreaction positive cells in the spinal cord were significantly more in model group (P<0.05). Compared with model group, those of EA-CV 4 and EA-ST 28 groups were obviously further increased (P<0.05), and the effect of EA-CV 4 group was markedly superior to that of EA-ST 28 group (P<0.05). CONCLUSION: EA of CV 4 and ST 28 can raise the excitability of the smooth muscle of the uninary bladder in rats with SCI-induced urinary retention, which may be related to its effects in upregulating the expression of BDNF and TrkB in the spinal cord. The effects of EA of CV 4 were evidently superior to those of EA of ST 28.