Long-Term Changes of Diffusion Tensor Imaging and Behavioural Status after Acupuncture Treatment in Rats with Transient Focal Cerebral Ischaemia

Neuroplasticity of Acupuncture for Stroke: An Evidence-Based Review of MRI

Acupuncture is widely recognized as a potentially effective treatment for stroke rehabilitation. Researchers in this area are actively investigating its therapeutic mechanisms. Magnetic resonance imaging (MRI), as a noninvasive, high anatomical resolution technique, has been employed to investigate neuroplasticity on acupuncture in stroke patients from a system level. However, there is no review on the mechanism of acupuncture treatment for stroke based on MRI. Therefore, we aim to summarize the current evidence about this aspect and provide useful information for future research. After searching PubMed, Web of Science, and Embase databases, 24 human and five animal studies were identified. This review focuses on the evidence on the possible mechanisms underlying mechanisms of acupuncture therapy in treating stroke by regulating brain plasticity. We found that acupuncture reorganizes not only motor-related network, including primary motor cortex (M1), premotor cortex, supplementary motor area (SMA), frontoparietal network (LFPN and RFPN), and sensorimotor network (SMN), as well as default mode network (aDMN and pDMN), but also language-related brain areas including inferior frontal gyrus frontal, temporal, parietal, and occipital lobes, as well as cognition-related brain regions. In addition, acupuncture therapy can modulate the function and structural plasticity of post-stroke, which may be linked to the mechanism effect of acupuncture.

Fire Acupuncture versus conventional acupuncture to treat spasticity after stroke: A systematic review and meta-analysis

BACKGROUND

Post-stroke spasm is currently a complex clinical problem that remains to be resolved. Due to its excellent efficacy and few side effects, clinicians have used fire acupuncture to treat post-stroke spasticity in China.

OBJECTIVES

The purpose of this study was to evaluate the clinical efficacy of fire acupuncture compared with conventional acupuncture to treat post-stroke spasms and provide a detailed summary of the commonly used acupoints.

METHODS

Eight databases (MEDLINE/PubMed, Web of Science, the Cochrane database, EMBASE, CBM, CNKI, WanFang, and VIP) were searched for randomized controlled trials (RCTs) published from database inception through August 30, 2020. RCTs that compared fire acupuncture with conventional acupuncture as a treatment intervention for patients with spasticity after stroke were included. Revman 5.3 software was used to calculate risk ratios (RR) and standard mean differences (SMD) with 95% confidence intervals (CI). Methodological evaluation or critical appraisal of the included articles was assessed using RoB-2.

RESULTS

Sixteen studies with a total of 1,118 patients were included. Although according to the standards of the Rob 2.0 tool, most studies are considered to have some problems. Comprehensive analysis of the results revealed a consistent trend indicating several advantages of using fire needles compared to conventional acupuncture in treating post-stroke spasms, including the effective rate, recovery rate, and improvement of multiple scales represented by MAS. Concerning secondary outcomes, using the scales of FMA, BI, or NDS in this random model meta-analysis, fire acupuncture exhibited better performance compared to acupuncture [SMD = 2.27, 95%CI [1.40,3.13 (random-effects model) ], [SMD = 1.46,95% CI [1.03,1.90 (random-effects model)], and [SMD = 0.90, 95%CI [0.44,1.35 (random-effects model)], respectively, with moderately high heterogeneity. When the effective rate was used as an outcome in the subgroup analysis, fire needles performed better than conventional acupuncture with respect to damage to the upper or lower limbs, and the thickness and depth of acupuncture. When the modified Ashworth scale (MAS) was used as the outcome, and the damage occurred in the lower extremity, the acupuncture depth exceeded 15mm, or the duration of stroke was longer than six months, the fire needles did not perform better than conventional acupuncture, [SMD = 0.01, 95%CI [-0.47,0.48 (fix-effects model)], [SMD = 0.21 [-0.51,0.93(random-effects model)], and [SMD = 0.76, 95%CI [-0.08,1.60 (random-effects model)], respectively. The acupoints identified with the highest frequencies in this study were Yang-meridian, including LI11-Quchi (nine times), LI4-Hegu (seven times), and ST36-Zusanli (five times). Moreover, no serious adverse effects were reported in any of the studies included in this analysis.

CONCLUSIONS

Despite several limitations, this was the first meta-analysis to focus on the treatment of post-stroke spasticity using fire needle acupuncture compared with conventional acupuncture. Our results confirmed that fire needles could provide a better clinical effect than conventional acupuncture, which will help standardize fire needle treatment strategies for post-stroke spasms.

Effects of acupuncture on cardiovascular risks in patients with hypertension: a Korean cohort study

OBJECTIVES

The aim of this study was to investigate the effects of acupuncture on major adverse cardiovascular events (MACE), myocardial infarction, stroke and death in hypertensive patients taking anti-hypertensives.

METHODS

Using the Korean National Health Insurance Service-National Sample Cohort (NHIS-NSC) database, this study identified 59,370 patients taking anti-hypertensives who had been diagnosed with hypertension between 2003 and 2006. They were divided into acupuncture and non-acupuncture groups. The follow-up period ended with the diagnosis of myocardial infarction, stroke or death. After propensity score matching (PSM), there were 18,011 patients each in the non-acupuncture and acupuncture groups. We calculated the incidence rate, hazard ratio (HR) and 95% confidence interval (CI) for MACE, myocardial infarction, stroke and death in patients with hypertension using a stratified Cox proportional hazard model. In addition, secondary outcome analyses for stroke and cardiovascular mortality were performed.

RESULTS

After PSM, the HRs for MACE (0.83, 95% CI 0.80-0.86), all-cause mortality (0.73, 95% CI 0.70-0.76) and myocardial infarction (0.85, 95% CI 0.79-0.92) were significantly lower in the acupuncture group than in the non-acupuncture group. Moreover, the HRs for stroke-related mortality, hemorrhage stroke-related mortality, ischemic stroke-related mortality, ischemic heart disease-related mortality and circulatory system disease-related mortality were significantly lower in the acupuncture group than in the non-acupuncture group.

CONCLUSION

This observational study with long-term follow-up extends the evidence base in support of the effectiveness of acupuncture for the management of hypertension and potentially reduce the burden of cardiovascular disease.

Application of survival analysis techniques to determine the optimal number of acupuncture therapy sessions for stroke patients

BACKGROUND

Acupuncture has shown clinical benefits in stroke patients but there is currently no clear recommendation on the number of acupuncture sessions that should be offered. The aim of this study was to determine the optimal number of acupuncture therapy sessions, following which significant clinical improvement could be anticipated.

METHODS

We performed a retrospective observational study in stroke patients who had received acupuncture therapy as an adjunct treatment at Trang Hospital-a non-academic provincial hospital in Southern Thailand-between 1 July 2016 and 30 June 2017. Significant clinical improvement in activities of daily living (ADLs) was defined as an increase in the Barthel Index of ⩾10 points from baseline. Survival analysis techniques were applied to determine the optimal number of acupuncture therapy sessions.

RESULTS

Of 89 patients, 78% had a significant clinical improvement. Kaplan-Meier analysis estimated that 50% of the patients exhibited significant improvements by the eighth acupuncture therapy session. By the 16th session, the proportion of patients increased to 81%. Subgroup analyses revealed that the clinical improvement did not depend on baseline Barthel index, whereas early treatment (within 3 months of stroke onset) was associated with a faster response than late treatment. The median numbers of sessions required to achieve a significant improvement in the early and late treatment groups were 8 and 11, respectively.

CONCLUSION

Stroke patients who were going to improve saw a significant improvement in Barthel index by the 16th acupuncture session and the marginal improvement declined substantially afterward. Our approach required minimal data available from the medical records of a non-academic facility, yet practical implication could be achieved.

TRIAL REGISTRATION

The study was retrospectively registered on 18 August 2017 with the Thai Clinical Trials Registry (ref. TCTR20170822002).

Longitudinal Brain Functional Connectivity Changes of the Cortical Motor-Related Network in Subcortical Stroke Patients with Acupuncture Treatment

In clinical practice, the effectiveness of the rehabilitation therapy such as acupuncture combining conventional Western medicine (AG) on stroke people's motor-related brain network and their behaviors has not been systematically studied. In the present study, seventeen adult ischemic patients were collected and divided into two groups: the conventional Western medicine treatment group (CG) and the AG. The neurological deficit scores (NDS) and resting-state functional MRI data were collected before and after treatment. Compared with the CG patients, AG patients exhibited a significant enhancement of the percent changes of NDS from pre- to posttreatment intervention. All patients showed significant changes of functional connectivity (FC) between the pair of cortical motor-related regions. After treatment, both patient groups showed a recovery of brain connectivity to the nearly normal level compared with the controls in these pairs. Moreover, a significant correlation between the percent changes of NDS and the pretreatment FC values of bilateral primary motor cortex (M1) in all patients was found. In conclusion, our results showed that AG therapy can be an effective means for ischemic stroke patients to recover their motor function ability. The FC strengths between bilateral M1 of stroke patients can predict stroke patients' treatment outcome after rehabilitation therapy.

Mechanisms of Acupuncture Therapy in Ischemic Stroke Rehabilitation: A Literature Review of Basic Studies

Acupuncture is recommended by the World Health Organization (WHO) as an alternative and complementary strategy for stroke treatment and for improving stroke care. Clinical trial and meta-analysis findings have demonstrated the efficacy of acupuncture in improving balance function, reducing spasticity, and increasing muscle strength and general well-being post-stroke. The mechanisms underlying the beneficial effects of acupuncture in stroke rehabilitation remain unclear. The aim of this study was to conduct a literature review, summarize the current known mechanisms in ischemic stroke rehabilitation through acupuncture and electroacupuncture (EA) therapy, and to detail the frequently used acupoints implicated in these effects. The evidence in this review indicates that five major different mechanisms are involved in the beneficial effects of acupuncture/EA on ischemic stroke rehabilitation: (1) Promotion of neurogenesis and cell proliferation in the central nervous system (CNS); (2) Regulation of cerebral blood flow in the ischemic area; (3) Anti-apoptosis in the ischemic area; (4) Regulation of neurochemicals; and, (5) Improvement of impaired long-term potentiation (LTP) and memory after stroke. The most frequently used acupoints in basic studies include Baihui (GV20), Zusanli (ST36), Quchi (LI11), Shuigou (GV26), Dazhui (GV14), and Hegu (LI4). Our findings show that acupuncture exerts a beneficial effect on ischemic stroke through modulation of different mechanisms originating in the CNS.

Neuronal Regeneration after Electroacupuncture Treatment in Ischemia-Reperfusion-Injured Cerebral Infarction Rats

Adult neuronal cells which can regenerate have been reported. The present study investigated whether acupuncture enhances neuronal regeneration in ischemic stroke rats. We established an ischemic stroke rat model by occluding the cerebral blood flow of the right middle cerebral artery for 15 minutes and then allowing reperfusion in Sprague–Dawley rats. The results indicated that, in these rats, 2 Hz electroacupuncture (EA) at both Zusanli (ST36) and Shangjuxu (ST37) acupoints reduced the infarction/hemisphere ratio 8 days after reperfusion and reduced the modified neurological severity score (mNSS) and increased the rotarod test time 4 and 8 days after reperfusion, respectively. In addition, 2 Hz reduced nestin immunoreactive cells in the penumbra area and the ischemic core area; 2 Hz EA also reduced Ki67 immunoreactive cells and increased glial fibrillary acidic protein immunoreactive cells in the penumbra area. These findings suggest that 2 Hz EA at the ST36 and ST37 acupoints has a neuroprotective role. However, additional studies are needed to further investigate these preliminary results.

The Effect of Acupuncture on the Motor Function and White Matter Microstructure in Ischemic Stroke Patients

Evidence shows that ischemic stroke can induce brain structural reorganization. Acupuncture is advised as an adjunct to mainstream rehabilitation after stroke. However, the effectiveness of acupuncture is inconsistent among previous studies. Fourteen ischemic patients were collected and divided into two groups: conventional treatment group (CG) and acupuncture treatment group (AG). The results of a Fugl-Meyer Assessment (FMA) and diffusion tensor imaging were collected before and after treatment. The AG exhibited a higher improvement in FMA than the CG. Repeated measures analysis of variance on diffusion data only found a significant main effect for scanning time point in all diffusion indices. In each group, a postpair t-test revealed that diffusion indices values were changed significantly after treatment intervention in the body of the corpus callosum and bilateral corticospinal tracts, the inferior longitudinal fasciculus, the inferior frontooccipital fasciculus, the superior longitudinal fasciculus, the forceps minor, the cingulum gyrus, and the thalamic radiation. However, there was no significant difference in the diffusion indices between the two groups. In conclusion, acupuncture had a better behavioral score than traditional medicine treatment. However, acupuncture did not significantly change WM in the AG compared to the CG as expected within one month after the intervention.

Molecular imaging in traditional Chinese medicine therapy for neurological diseases

With the speeding tendency of aging society, human neurological disorders have posed an ever increasing threat to public health care. Human neurological diseases include ischemic brain injury, Alzheimer's disease, Parkinson's disease, and spinal cord injury, which are induced by impairment or specific degeneration of different types of neurons in central nervous system. Currently, there are no more effective treatments against these diseases. Traditional Chinese medicine (TCM) is focused on, which can provide new strategies for the therapy in neurological disorders. TCM, including Chinese herb medicine, acupuncture, and other nonmedication therapies, has its unique therapies in treating neurological diseases. In order to improve the treatment of these disorders by optimizing strategies using TCM and evaluate the therapeutic effects, we have summarized molecular imaging, a new promising technology, to assess noninvasively disease specific in cellular and molecular levels of living models in vivo, that was applied in TCM therapy for neurological diseases. In this review, we mainly focus on applying diverse molecular imaging methodologies in different TCM therapies and monitoring neurological disease, and unveiling the mysteries of TCM.

Brain connectivity plasticity in the motor network after ischemic stroke

The motor function is controlled by the motor system that comprises a series of cortical and subcortical areas interacting via anatomical connections. The motor function will be disturbed when the stroke lesion impairs either any of these areas or their connections. More and more evidence indicates that the reorganization of the motor network including both areas and their anatomical and functional connectivity might contribute to the motor recovery after stroke. Here, we review recent studies employing models of anatomical, functional, and effective connectivity on neuroimaging data to investigate how ischemic stroke influences the connectivity of motor areas and how changes in connectivity relate to impaired function and functional recovery. We suggest that connectivity changes constitute an important pathophysiological aspect of motor impairment after stroke and important mechanisms of motor recovery. We also demonstrate that therapeutic interventions may facilitate motor recovery after stroke by modulating the connectivity among the motor areas. In conclusion, connectivity analyses improved our understanding of the mechanisms of motor recovery after stroke and may help to design hypothesis-driven treatment strategies and sensitive measures for outcome prediction in stroke patients.

Acupuncture therapy for stroke patients

Acupuncture is one of the most important parts of Traditional Chinese Medicine, has been used for more than 3000 years as prevention and treatment for various diseases in China as well as in adjacent regions, and is widely accepted in western countries in recent years. More and more clinical trials revealed that acupuncture shows positive effect in stroke, not only as a complementary and alternative medicine for poststroke rehabilitation but also as a preventive strategy which could induce cerebral ischemic tolerance, especially when combined with modern electrotherapy. Acupuncture has some unique characteristics, which include acupoint specificity and parameter-dependent effect. It also involves complicated mechanism to exert the beneficial effect on stroke. Series of clinical trials have shown that acupuncture primarily regulates the release of neurochemicals, hemorheology, cerebral microcirculation, metabolism, neuronal activity, and the function of specific brain region. Animal studies showed that the effects of acupuncture therapy on stroke were possibly via inhibition of postischemic inflammatory reaction, stimulation of neurogenesis and angiogenesis, and influence on neural plasticity. Mechanisms for its preconditioning effect include activity enhancement of antioxidant, regulation of the endocannabinoid system, and inhibition of apoptosis. Although being controversial, acupuncture is a promising preventive and treatment strategy for stroke, but further high-quality clinical trials would be needed to provide more confirmative evidence.