Acupuncture for Psychological Disorders Caused by Chronic Pain: A Review and Future Directions

A neural circuit associated with anxiety-like behaviors induced by chronic inflammatory pain and the anxiolytic effects of electroacupuncture

AIMS

Negative emotions induced by chronic pain are a serious clinical problem. Electroacupuncture (EA) is a clinically proven safe and effective method to manage pain-related negative emotions. However, the circuit mechanisms underlying the effect of EA treatment on negative emotions remain unclear.

METHODS

Plantar injection of complete Freund's adjuvant (CFA) was performed to establish a rat model of chronic inflammatory pain-induced anxiety-like behaviors. Adeno-associated virus (AAV) tracing was used to identify excitatory synaptic transmission from the rostral anterior cingulate cortex (rACC) to the dorsal raphe nucleus (DRN). Employing chemogenetic approaches, we examined the role of the rACC-DRN circuit in chronic pain-induced anxiety-like behaviors and investigated whether EA could reverse chronic pain-induced dysfunctions of the rACC-DRN circuit and anxiety-like behaviors.

RESULTS

We found that chemogenetic activation of the rACC-DRN circuit alleviated CFA-induced anxiety-like behaviors, while chemogenetic inhibition of the rACC-DRN circuit resulted in short-term CFA-induced anxiety-like behaviors. Further research revealed that the development of CFA-induced anxiety-like behaviors was attributed to the dysfunction of rACC CaMKII neurons projecting to DRN serotonergic neurons (rACCCaMKII-DRN5-HT neurons) but not rACC CaMKII neurons projecting to DRN GABAergic neurons (rACCCaMKII-DRNGABA neurons). This is supported by the findings that chemogenetic activation of the rACCCaMKII-DRN5-HT circuit alleviates anxiety-like behaviors in rats with chronic pain, whereas neither chemogenetic inhibition nor chemogenetic activation of the rACCCaMKII-DRNGABA circuit altered CFA chronic pain-evoked anxiety-like behaviors in rats. More importantly, we found that EA could reverse chronic pain-induced changes in the activity of rACC CaMKII neurons and DRN 5-HTergic neurons and that chemogenetic inhibition of the rACCCaMKII-DRN5-HT circuit blocked the therapeutic effects of EA on chronic pain-induced anxiety-like behaviors.

CONCLUSIONS

Our data suggest that the reversal of rACCCaMKII-DRN5-HT circuit dysfunction may be a mechanism underlying the therapeutic effect of EA on chronic pain-induced anxiety-like behaviors.

Functional connectivity patterns are altered by low back pain and cause different responses to sham and real dry needling therapies: a systematic review of fMRI studies

BACKGROUND

There is a relationship between low back pain (LBP) and central nervous system dysfunction. Needling therapies (e.g. acupuncture, dry needling) are proposed to impact the nervous system, however their specific influence is unclear.

PURPOSE

Determine how needling therapies alter functional connectivity and LBP as measured by functional magnetic resonance imaging (fMRI).

METHODS

Databases were searched following PRISMA guidelines. Studies using fMRI on individuals with LBP receiving dry needling or acupuncture compared to control or sham treatments were included.

RESULTS

Eight studies were included, all of which used acupuncture. The quality of studies ranged from good (n = 6) to excellent (n = 2). After acupuncture, individuals with LBP demonstrated significant functional connectivity changes across several networks, notably the salience, somatomotor, default mode network (DMN) and limbic networks. A meta-analysis demonstrated evidence of no effect to potential small effect of acupuncture in reducing LBP (SMD -0.28; 95% CI: -0.70, 0.13).

CONCLUSION

Needling therapies, like acupuncture, may have a central effect on patients beyond the local tissue effects, reducing patients' pain and disability due to alterations in neural processing, including the DMN, and potentially other central nervous system effects. The meta-analysis should be interpreted with caution due to the narrow focus and confined sample used.

Research hotspots and trends on acupuncture treatment for headache: a bibliometric analysis from 2003 to 2023

Background

While acupuncture treatment has gained extensive usage in addressing headaches, there remains a notable gap in the literature analysis for this field. Therefore, this study aims to conduct a literature review using Citespace, VOSviewer, and Bibliometrix, aiming to examine the current status, strengths, and potential future directions in the utilization of acupuncture for headache treatment.

Methods

Relevant literature on acupuncture treatment for headaches between 2003 and 2023 was retrieved from the Web of Science (WoS) core database. Utilizing CiteSpace 6.1.R6, VOSviewer 1.6.18, and Bibliometrix 4.1.4, we conducted bibliometric analyses across various categories, including countries/regions, institutions, authors, journals, references, and keywords.

Results

A total of 808 research reports were included. China and the United States have significantly contributed to this field. Chengdu University of Chinese Medicine holds the record for the highest number of published papers. Liu Lu has the highest publication output, while Linde K has the highest citation rate. MEDICINE leads in publication frequency, while CEPHALALGIA holds the highest citation rate. The Long-term Effect of Acupuncture for Migraine Prophylaxis a Randomized Clinical Trial is the most cited reference. Migraine was the most researched type. Filiform needle acupuncture was the most widely used stimulation method. The safety and efficacy of acupuncture have received significant attention. Modern mechanism research shows that depression, brain functional connectivity, and neuroimaging technology have become research hotspots in the acupuncture treatment of headaches.

Conclusion

Acupuncture treatment for headaches has established a stable trend with a promising developmental trajectory. Research in this field mainly focuses on different acupuncture prevention and treatment for various types of headaches, the safety and efficacy of acupuncture, etc. Research on the mechanism of action mainly focuses on interpreting bidirectional and holistic regulation between pain and emotion by acupuncture and the regulation of brain function connection and neuroimaging technology by acupuncture. Future research should expand on the advantages and indications of acupuncture treatment for different headaches and their modern mechanisms.

The Emotion Regulation of Acupuncture in Chronic Low Back Pain: A Clinical Neuroimaging Protocol

Introduction

Acupuncture is effective for patients with chronic low back pain (CLBP), which can relieve pain intensity and regulate negative emotional states such as pain-related anxiety and depression. Previous studies mainly discuss the analgesic mechanism of acupuncture treatment of CLBP, but there are multiple dimensions to pain, including sensation, emotion and cognition. Therefore, this study aims to investigate the central mechanism of acupuncture for CLBP from the perspective of emotional regulation by functional magnetic resonance imaging (fMRI).

Methods and Analysis

A total of 72 patients with CLBP will be recruited in the study and randomly assigned to the verum acupuncture group or the sham acupuncture group. The trail will last for 18 weeks including a 2-week baseline, a 4-week treatment and a 12-week for follow-up period. The primary outcomes are the visual analog scale (VAS) and the Japanese Orthopaedic Association Scores (JOA) score. The secondary outcomes are the 12-item short form health survey (SF-12), the state trait anxiety inventory (STAI), the self-rating anxiety scale (SAS) and self-rating depression scale (SDS). The VAS, JOA, STAI SAS and SDS will be collected at baseline, week 2, week 4, and after follow-up. The SF-12 will be evaluated at baseline, week 2 and week 4. Functional magnetic resonance imaging (MRI) data will be collected at baseline and the end of treatment. Emotion-related brain regions will be chosen as regions of interest (ROIs). The gray matter volume (GMV), amplitude of low-frequency fluctuation (ALFF), regional homogeneity (ReHo), functional connectivity (FC), and large-scale functional brain network based on these ROIs will be analyzed within and between the two groups.

Discussion

This study will verify the emotional regulation of acupuncture and explore the mechanism of acupuncture for emotion regulation in patients with CLBP.

Trial Registration Number

https://www.chictr.org.cn/showproj.html?proj=195486, identifier: ChiCTR2300070557.

Scalp electroacupuncture targeting the VTADA neurons to relieve negative emotions and promote the alleviation of chronic pain

Object

Chronic pain and negative emotions are often linked, and both can impact the reward circuit. The use of electroacupuncture (EA) has been found to regulate and improve these conditions. This study explores the potential mechanism of chronic pain relief by adding acupoints with emotional regulation effect to the basis of routine EA analgesia, to optimize the acupoint compatibility scheme of EA in the treatment of analgesia.

Method

For this study, 42 male Wistar rats were used. Recombinant adeno-associated viruses were used to label and regulate the activity of dopamine (DA) neurons. The rat model was established by complete Freund's adjuvant (CFA). Lower limb electroacupuncture (LEA) was applied to the ST36 and BL60 acupoints. In addition, LEA + scalp EA (SEA) was given using the GV20 and GV24+ acupoints besides ST36 and BL60. To evaluate the pain threshold, we measured 50% paw withdrawal thresholds and thermal paw withdrawal latencies. Negative emotions were evaluated through the open field test, marble-burying test, sucrose preference test, and forced swimming test. Moreover, the conditional place preference test was conducted to measure the reward behavior in response to pain relief. Immunofluorescence staining, Western blotting, and qPCR were used to detect the activity of the VTADA-NAc reward circuit.

Result

The injection of CFA significantly lowered the pain threshold. As the pain persisted, the anxiety and depression-like behaviors escalated while the response to reward reduced. Meanwhile, the VTADA-NAc pathway was suppressed with pain chronification. However, activating DA neurons in VTA attenuated the effects induced by CFA. LEA could relieve chronic pain, negative emotions, and reward disorders, while also activating the VTADA-NAc pathway. In addition, LEA + SEA exhibited a more pronounced effect compared with LEA alone. Nevertheless, chemogenetic inhibition of DA neurons decreased the efficacy of LEA + SEA in the treatment of chronic pain and associated comorbidities.

Conclusion

Adding SEA to conventional LEA effectively alleviates negative emotions and chronic pain, potentially due to the activation of the VTADA-NAc reward neural circuit. Thus, LEA + SEA is a more effective treatment for hyperalgesia and associated negative emotions compared with LEA alone.

Manual acupuncture for neuromusculoskeletal disorders: The selection of stimulation parameters and corresponding effects

As a minimally invasive method of physical stimulation, manual acupuncture (MA) is used globally as a sort of therapy for neuromusculoskeletal disorders. In addition to selecting appropriate acupoints, acupuncturists should also determine the stimulation parameters of needling, such as the manipulation (lifting-thrusting or twirling), needling amplitude, velocity, and stimulation time. At present, most studies focus on acupoint combination and mechanism of MA, the relationship between stimulation parameters and their therapeutic effects, as well as the influence on mechanism of action are relatively scattered, and lack of systematic summary and analysis. This paper reviewed the three types of stimulation parameters of MA, their common options and values, corresponding effects and potential mechanisms of action. The purpose of such efforts is to provide a useful reference for the dose-effect relationship of MA and the quantification and standardization of its clinical treatment of neuromusculoskeletal disorders to further promote the application of acupuncture in the world.

Assessment of quality of life and activities of daily living among elderly patients with hypertension and impaired physical mobility in home health care by antihypertensive drugs plus acupuncture: A CONSORT-compliant, randomized controlled trial

BACKGROUND

To evaluate the efficacy of acupuncture in improving quality of life (QOL) and activities of daily living among elderly patients with hypertension and impaired physical mobility in home health care.

METHODS

Seventy participants were allocated randomly to receive either acupuncture together with antihypertensive drugs (n = 35) or antihypertensive drugs only (n = 35). Acupuncture was conducted twice a week for 12 consecutive weeks, each lasting 30 minutes. Acupuncture points San Yin Jiao, Xue Hai, Taichong, Zusanli, and Hegu acupuncture points were used bilaterally. The primary outcome was change in QOL score, evaluating by Short-Form 36 Item Health Survey (SF-36). Secondary outcomes were changes in Barthel index score and blood pressure. Besides, pain evaluation by Visual analog scale, among acupuncture and control subgroups in participants with diagnosis with disease of the musculoskeletal system and connective tissue (ICD-9: 710-739).

RESULTS

Thirty-one participants in each of the acupuncture group and the control group completed the study. After 12 weeks of treatment, compared with the control group, the combination of antihypertensive treatments and acupuncture helped to improve bodily pain (P = .03), physical component summary (P = .04), mental health (P < .001), mental component summary (P = .008), Barthel index (P = .02), and systolic blood pressure (P = .01). In contrast, the control group showed no significant changes. Change in pain score revealed that there were a significant between-group differences after 6weeks (P = .01) and 12weeks of treatment (P = .001).

CONCLUSION

The results of the study suggested that in home health care elderly patients with hypertension and impaired physical mobility, antihypertensive drugs combined with acupuncture therapy will be more beneficial to improve QOL, activities of daily living, and blood pressure.

Clinical effects of glabellar botulinum toxin injections on borderline personality disorder: A randomized controlled trial

BACKGROUND

Inhibition of frowning via injections of botulinum toxin A (BTX) into the glabellar region has shown beneficial effects in the treatment of major depression. Preliminary research suggests that improvements in the affective domain are not depression-specific, but may also translate to other psychiatric disorders.

AIM

This 16-week, single-blind, two-center randomized controlled trial investigated the influence of BTX on clinical symptoms of borderline personality disorder (BPD).

METHODS

Fifty-four patients with BPD were randomly assigned to treatment with BTX (n = 27) or a minimal acupuncture (ACU) control condition (n = 27). Clinical outcomes were followed at 2, 4, 6, 8, 12, and 16 weeks. Primary endpoint was the relative score change on the Zanarini Rating Scale for Borderline Personality Disorder (ZAN-BPD) 8 weeks after baseline relative to the control group and adjusted for treatment center. Secondary and additional outcome variables were self-rated borderline symptoms, comorbid symptoms of depression, psychological distress, and clinical global impression.

RESULTS

Participants showed significant improvements at the primary efficacy endpoint in both treatment groups (BTX: M = -0.39, SD = 0.39; ACU: M = -0.35, SD = 0.42), but no superior effect of the BTX condition in comparison with the control intervention was found-F(1,5323) = 0.017, p = 0.68). None of the secondary or additional outcomes yielded significant group differences. Side effects were mild and included headache, transient skin or muscle irritations, and dizziness.

CONCLUSION

Evidence regarding the efficacy of BTX for BDP remains limited, and the design of adequate control conditions presents an opportunity for further research.ClinicalTrials.gov registry: Botulinum Toxin A for Emotional Stabilization in Borderline Personality Disorder (BPD), NCT02728778, https://clinicaltrials.gov/ct2/show/NCT02728778.

Potential Mechanisms of Acupuncture for Functional Dyspepsia Based on Pathophysiology

Functional dyspepsia (FD), a common disorder of gastrointestinal function, originated from the gastroduodenum. Although the therapeutic effect of acupuncture has been investigated by various high-quality randomized controlled trials, the potential mechanisms showed obvious heterogeneity. This review summarized the potential mechanisms of acupuncture on FD in order to guide for future laboratory and clinical studies. Here, we argued that the primary cause of FD was gastroduodenal low-grade inflammation and acid exposure, which impaired mucosal integrity, caused brain-gut axis dysfunction, and impaired brain network connectivity, all of which generated various symptom patterns. Overall the clinical studies indicated that acupuncture was a promising treatment to alleviate symptoms in FD patients, whose efficacy was influenced by acupoints and individual variance. Mechanistically, studies with animal models of FD and patients have shown that acupuncture, a non-invasive strategy for nerve stimulation, may have the potential to control intestinal inflammation and suppress acid-secretion via different somatic autonomic reflex pathways, regulate the brain-gut axis through intestinal microbiota, and has the potential to ameliorate FD-symptoms. The cumulative evidence demonstrated that acupuncture is a promising treatment to alleviate symptoms of FD patients.

Contralateral Acupuncture for the Treatment of Phantom Limb Pain and Phantom Limb Sensation in Oncologic Lower Limb Amputee: A Case Report

Phantom limb pain (PLP) and phantom limb sensation (PLS) are common and distressing sequelae of amputation. Current pain management following amputation is challenging and unsatisfying. In this case study, a 74-year-old woman underwent above-knee amputation because of the rhabdomyosarcoma in the right leg. Despite several analgesics, pain was poorly controlled. The phantom limb pain and sensation were immediately reduced by the contralateral acupuncture, and abolished after the third session with no side-effects, no relapse during the next 9 months. Contralateral acupuncture showed positive effect on PLP and PLS in this case, but more robust evidence would be needed to support the efficacy of this treatment technique for indication.

Electroacupuncture Ameliorates Chronic Inflammatory Pain-Related Anxiety by Activating PV Interneurons in the Anterior Cingulate Cortex

Chronic inflammatory pain is a common clinical disease that tends to be associated with negative emotions such as anxiety and depression. The anterior cingulate cortex (ACC) is involved in pain and pain-related anxiety, and γ-aminobutyric acid (GABA)-ergic interneurons play an important role in chronic pain and anxiety. Electroacupuncture (EA) has good analgesic and antianxiety effect, but the underlying mechanisms have not yet been fully elucidated. In this study, we established a chronic inflammatory pain model and observed that this model induced anxiety-like behaviors and decreased the numbers of parvalbumin (PV) and somatostatin (SOM) positive cells. Activation of PV but not SOM interneurons by chemogenetic techniques alleviated anxiety-like behaviors and pain sensation. EA treatment improved pain sensation, anxiety-like behaviors and increased the number of PV- positive cells in the ACC, but did not affect on the number of SOM-positive cells in the ACC. Moreover, specific inhibition of PV interneurons by chemogenetic methods reversed the analgesic and antianxiety effects of EA. These results suggest that EA ameliorates chronic inflammatory pain and pain-related anxiety by upregulating PV but not SOM interneurons in the ACC.