Analgesic Effect Of Acupuncture Research Articles

Dose-effect relationship between electroacupuncture with different parameters and the regulation of endogenous opioid peptide system: 不同参数电针对内源性阿片肽系统调节的量效关系

Endogenous opioid peptides (EOP) are the neurochemical basis of the anesthetic and analgesic effects of acupuncture, and the quantity of acupuncture stimulus can be controlled accurately by using electroacupuncture (EA). The present study explores the dose-effect relationship between EA with different parameters and the regulation of EOP system. In this paper, the intervention effects of EA on EOP system were specially discussed in terms of the single factor and the different combinations of the frequency, waveform and current intensity. This study shows that EOP system presents a frequency-response specificity. The low frequency of EA promotes the release of enkephalin, β-endorphin and endomorphin, the high one activates the dynorphin system selectively, and the intermediate frequency works on promoting the release of enkephalin and β-endorphin, as well as dynorphin. Sparse-dense wave of EA may induce the release of enkephalin, β-endorphin, endomorphin and dynorphin, presenting a synergistic effect. However, the waveform of EA should be selected flexibly in clinical practice. Sometimes the better therapeutic effect can also be obtained with the continuous wave of EA. EOP system is involved in mediating appropriate intensity of EA, while the acupuncture effect generated by an extra strong EA stimulation refers to a kind of stress response of non-opioid mechanism. The different combinations of EA parameters result in various effects. The combination of EA parameters should be optimized in accordance with different diseases, which is valuable for guiding clinical practice and the development of EA therapy.

Modulation effects of different treatments on periaqueductal gray resting state functional connectivity in knee osteoarthritis knee pain patients.

The analgesic effect of acupuncture is widely recognized, but the mechanical characteristics of acupuncture for pain relief, compared to non-steroidal anti-inflammatory (NSAIDs) and placebo medication, remain unknown. To compare the modulation effects of acupuncture treatment with NSAIDs and placebo medication on descending pain modulation system (DPMS) in knee osteoarthritis (KOA) patients. This study recruited 180 KOA patients with knee pain and 41 healthy controls (HCs). Individuals with KOA knee pain were divided randomly into groups of verum acupuncture (VA), sham acupuncture (SA), celecoxib (SC), placebo (PB), and waiting list (WT), with 36 patients in each group. VA and SA groups included ten sessions of puncturing acupoints or puncturing non-acupoints acupuncture treatment for two successive weeks. Celecoxib capsules were continuously given orally to patients in the SC group at a dosage of 200 mg daily for 2 weeks. In the PB group, patients received a placebo capsule once a day for 2 weeks at the same dosage as celecoxib capsules. In the WL group, patients did not receive any treatment. Patients underwent a resting-state BOLD-fMRI scan pre- and post-receiving the therapy, whereas HCs only underwent a baseline scan. Seed (ventrolateral periaqueductal gray, vlPAG, a key node in DPMS) based resting-state functional connectivity (rs-FC) was applied in the data analysis. All groups demonstrated improved knee pain scores relative to the initial state. There was no statistical difference between the VA and SA groups in all clinical outcomes, and vlPAG rs-FC alterations. KOA knee pain individuals reported higher vlPAG rs-FC in the bilateral thalamus than HCs. KOA knee pain patients in the acupuncture group (verum + sham, AG) exhibited increased vlPAG rs-FC with the right dorsolateral prefrontal cortex (DLPFC) and the right angular, which is associated with knee pain improvement. In contrast with the SC and PB group, the AG exhibited significantly increased vlPAG rs-FC with the right DLPFC and angular. Contrary to the WT group, the AG showed greater vlPAG rs-FC with the right DLPFC and precuneus. Acupuncture treatment, celecoxib, and placebo medication have different modulation effects on vlPAG DPMS in KOA knee pain patients. Acupuncture could modulate vlPAG rs-FC with brain regions associated with cognitive control, attention, and reappraisal for knee pain relief in KOA patients, compared with celecoxib and placebo medication.

Bibliometric Analysis of 100 Most Highly Cited Publications on Acupuncture for Migraine.

Migraine is a serious global health concern that imposed a huge economic burden on social health care. Over the past few decades, the analgesic effects of acupuncture have been widely recognized, and there is a growing body of research on acupuncture for migraine. Citation analysis is a branch of bibliometrics that helps researchers analyze and identify historical or landmark studies within the scientific literature. Currently, there is no analysis of the 100 most highly cited publications on acupuncture for migraine. The 100 most highly cited publications on acupuncture for migraine were screened using the Science Citation Index Expanded of the Web of Science Core Collection database. CiteSpace and VOSviewer programs were used for bibliometric analysis. A total of 493 publications on acupuncture for migraine were identified. 100 of the most highly cited publications on acupuncture for migraine were published from 1984-2020. These publications were cited 6142 times with an h-index of 44 and 84% were original articles. The highest frequency of citations was 416. A total of 335 authors were involved in the study with 37 lead authors. 212 institutions from 20 countries contributed to the 100 most highly cited publications. The most published studies came from the United States (n=36), followed by China (n=27) and Germany (n=26). The Technical University of Munich published the largest number of papers (n = 15). Top-cited publications mainly came from the Headache (n=13, citations=582). Neuroimaging is gradually emerging as a hot topic of research. This is the first bibliometric analysis to offer a thorough list of the 100 most highly cited papers on acupuncture for migraine, demonstrating significant progress and emerging trends in this field to assist researchers in determining the direction for further research.

Revealing the Central Mechanism of Acupuncture for Primary Dysmenorrhea Based on Neuroimaging: A Narrative Review.

The central mechanism of acupuncture for primary dysmenorrhea was explored by summarizing the changes in different regional networks of the brain induced by acupuncture stimulation by analyzing the existing studies. The original studies were collected and selected from three English databases such as PubMed and four Chinese databases as China Knowledge Network (CNKI). The main keyword clusters are neuroimaging, acupuncture, and primary dysmenorrhea. The literature review yielded 130 possibly qualified studies, and 23 articles fulfilled the criteria for inclusion. Regarding the type of acupuncture studies, 6 moxibustion studies and 17 manual acupuncture studies for primary dysmenorrhea were included. Based on functional magnetic resonance imaging (fMRI), perfusion-weighted imaging (PWI), and positron emission tomography-computer tomography techniques (PET-CT), one or more analysis methods such as amplitude of low-frequency fluctuations (ALFF), regional homogeneity (ReHo), functional connectivity (FC), and independent components analysis (ICA) were used. The results are summarized. To summarize the high-frequency brain area alterations observed in patients with acupuncture-induced primary dysmenorrhea were the anterior cingulate gyrus, thalamus, insula, precentral gyrus, middle frontal gyrus, postcentral gyrus, putamen, and cerebellum. The results suggest that the mechanism of acupuncture in the treatment of primary dysmenorrhea is the involvement of networks regulating different areas of the brain in the analgesic effects of acupuncture. The brain regions involved in primary dysmenorrhea acupuncture analgesia were mainly located in the pain matrix, default mode network, salience network, and limbic system.

Mast Cell-Associated Serotonin in Acupoint Contributes to Acupuncture Analgesia in Arthritis Rats by Mediating ATP Release.

The activation of subcutaneous mast cells (MCs) helps to trigger the analgesic effect induced by acupuncture (AP), a traditional oriental therapy, that has been gradually accepted worldwide. This work aimed to reveal whether the serotonin (5-hydroxytryptamine, 5-HT) released from MCs plays an important role in this process, which has a controversial effect in the mechanism of pain. In vivo tests, a 20-min session of AP was applied at Zusanli acupuncture point (acupoint) of acute ankle arthritis rats. Pain thresholds of the injured hindpaw were assessed to reflect the pain state, and the targeting substances in the interstitial space of the treated acupoint were sampled by microdialysis. In vitro experiments, exogenous 5-HT (exo-5-HT) was introduced to mediate adenosine triphosphate (ATP) release from cultured MCs. Needling promoted 5-HT accumulation at the Zusanli acupoint, which was prevented by sodium cromolyn. AP's analgesic effect was suppressed by the inhibition of 5-HT receptors at the acupoint, especially 5-HT1A subtype. In vitro tests, mechanical perturbation mimicking needling stimulation induced MCs to release 5-HT. 1 μM and 10 μM of exo-5-HT facilitated ATP release, which was restrained by blocking of 5-HT1 receptors rather than 5-HT3 receptors. As 5-HT, ATP and adenosine were also transiently accumulated in the treated acupoint during needling. Promoting ATP hydrolysis or activation adenosine A1 receptors duplicated AP analgesic effect. Finally, the inhibition of ATP receptors by suramin or pyridoxal phosphate-6-azo tetrasodium salt hydrate (PPADS) prevented AP analgesic effect. Our results suggest that MC-associated 5-HT release at acupoints contributes to AP analgesia, and the mediation of ATP secretion through 5-HT1A receptors might be the underlying mechanism at play. ATP could facilitate adenosine production or the propagation of needling signals.

Acupuncture as an additional analgesic method in the perioperative period

Acupuncture is a traditional Chinese therapeutic method that uses a sterile thin needle technique to puncture the skin at specific strategic points on the body. World Health Organisation has acknowledged acupuncture as a complementary treatment method for over 300 diseases. Nowadays, many available studies conducted in China, the United States, and Europe confirm the efficacy of acupuncture, its analgesic effect, while providing direct health benefits without or with minimal side-effects. There are many scientific evidence mechanisms of acupuncture?s analgesic effects. One of the mechanisms is described in the oldest and best-known Gate Control Theory which explains how pain pathways are modulated through normal anti-nociceptive pathways in the spinal cord. The second mechanism of analgesia shows that there are changes in descendent inhibition of pain pathway and secretion of neurotransmitters when the acupuncture needle is placed at the specific acupuncture point. In addition, it has been proved that there is an increased secretion of endogenous opioids during acupuncture procedures, which help reduce the pain sensations. Analgesic effects of acupuncture on cerebral function have been confirmed with use of functional magnetic resonance imaging and positron emission tomography scans. Although there is an increased number of relevant studies that confirm the effects and benefits of acupuncture therapy in the perioperative period, some important factors are still missing: the standardization process of acupuncture technique, the determination of types of surgery where the acupuncture method shows the best therapeutic effect, the determination of the best technique and time interval for the most effective analgesia.

Proteomic analysis of rat colonic mucosa following acupuncture treatment for irritable bowel syndrome with diarrhea

To investigate the molecular pathological mechanisms of irritable bowel syndrome with diarrhea (IBS-D) and elucidate the effects of acupuncture on IBS-D colonic mucosa protein abundance in rats, a label-free high-throughput liquid chromatography-tandem mass spectrometry (LC-MS)-based proteomics analysis was used to survey the global changes of colonic mucosa proteins between different groups. Sixteen Sprague-Dawley (SD) male rats were randomly divided into four groups: the control group (C); the IBS-D model group (M); the syndrome differentiation acupuncture group (SD) and the traditional acupuncture group (T). IBS-D model rats were obtained using the CAS (chronic acute combining stress model) method. Comparative bioinformatics analysis of the proteomic data was analyzed using MaxQuant software, Perseus software, online tools DAVID, VENNY and STRING. Functional enrichment and network analyses revealed a close relationship between IBS-D and several biological processes including energy metabolism, muscular excitation/contraction, and both traditional acupuncture and syndrome differentiation acupuncture can reverse the impairments of normal energy metabolism. Moreover, the syndrome differentiation acupuncture can regulate the protein cluster relating inflammation, wound repair and cell protection against oxidative stress which is associated with acupuncture analgesic effect. Differentially expressed proteins Atp5a1 and Bpnt1 were selected as representative proteins and subjected to western blotting. In conclusion, our study provides further insight into the pathological and molecular mechanisms of IBS-D and acupuncture treatments, and serves as an experimental basis for clinical applications.

Effective Oriental Magic for Analgesia: Acupuncture.

Pain is a kind of complex physiological and psychological symptom, which makes the person debilitated and uncomfortable. Some persistent pain is unbearable for the patients, reducing the quality of life and bringing considerable pressure to the individuals and society. Pain killers seem to be effective in analgesia for patients, but their safety and addiction are crucial issues. From the theory of traditional Chinese medicine (TCM), the blocked meridian is the main cause of pain, and effective acupuncture can play a positive analgesic effect. Acupuncture that can date back thousands of years is one of the ancient medical practices in China. Its safety and effectiveness are respected. Based on its superior safety and inferior side effects, it has been gradually recognized as a therapeutic intervention method for complementary medicine, which is also generally used to treat multiple pain diseases. It is shown by modern medical studies that neurotransmitters are the material basis for the acupuncture effect, and the effect of acupuncture analgesia is related to changes in neurotransmitters. However, the specific mechanism has not been elucidated. This review aims to comprehensively discuss the historical evolution of acupuncture analgesia, clinical research of acupuncture analgesia, comparison of acupuncture and drug therapy, the neurotransmitter mechanism of acupuncture analgesia, the effect of acupuncture manipulation on analgesia, and bibliometric analysis of acupuncture treatment for pain, to explore the superiority and related mechanism of acupuncture analgesia from different aspects, and to provide a more effective treatment for alleviating patients' pain.

Problems in randomized controlled trial on acupuncture and moxibustion for migraine in the development of international standard of Guideline for Clinical Practice of Acupuncture and Moxibustion: Migraine

Regarding the development of international standard of Guideline for Clinical Practice of Acupuncture and Moxibustion: Migraine, the existing problems of the design and methodology of randomized controlled trial (RCT) on acupuncture and moxibustion for migraine were summarized in views of participant, intervention, control, outcome and study design. Four directions need to be further explored, (1) research of adolescent migraine, special subtype of migraine and migraine in a special population; (2) research of the immediate analgesic effect of acupuncture and moxibuation at the attack stage of migraine and the therapeutic effect of migraine at each stage; (3) research on safety and health economics; (4) clinical trial registration of acupuncture and moxibustion. In study, the target population should be further determined and specialized, the diagnosis criteria of western medicine and traditional Chinese medicine be generalized and concentrated, the staging and type division of disease be accurate, the intervention procedure be integrated, the control design be rationalized, the outcomes be validated, and the description of randomization and blinding be clarified.

Analgesic effect of acupuncture in patients with stable angina: integrative review

Analgesic effect of acupuncture in patients with stable angina: integrative review

Role of Neuroimmune Crosstalk in Mediating the Anti-inflammatory and Analgesic Effects of Acupuncture on Inflammatory Pain.

Inflammatory pain is caused by peripheral tissue injury and inflammation. Inflammation leads to peripheral sensitization, which may further cause central sensitization, resulting in chronic pain and progressive functional disability. Neuroimmune crosstalk plays an essential role in the development and maintenance of inflammatory pain. Studies in recent years have shown that acupuncture can exert anti-inflammatory and analgesic effects by regulating peripheral (i.e., involving local acupoints and inflamed regions) and central neuroimmune interactions. At the local acupoints, acupuncture can activate the TRPV1 and TRPV2 channels of mast cells, thereby promoting degranulation and the release of histamine, adenosine, and other immune mediators, which interact with receptors on nerve endings and initiate neuroimmune regulation. At sites of inflammation, acupuncture enables the recruitment of immune cells, causing the release of opioid peptides, while also exerting direct analgesic effects via nerve endings. Furthermore, acupuncture promotes the balance of immune cells and regulates the release of inflammatory factors, thereby reducing the stimulation of nociceptive receptors in peripheral organs. Acupuncture also alleviates peripheral neurogenic inflammation by inhibiting the release of substance P (SP) and calcitonin gene-related peptide from the dorsal root ganglia. At the central nervous system level, acupuncture inhibits the crosstalk between glial cells and neurons by inhibiting the p38 MAPK, ERK, and JNK signaling pathways and regulating the release of inflammatory mediators. It also reduces the excitability of the pain pathway by reducing the release of excitatory neurotransmitters and promoting the release of inhibitory neurotransmitters from neurons and glial cells. In conclusion, the regulation of neuroimmune crosstalk at the peripheral and central levels mediates the anti-inflammatory and analgesic effects of acupuncture on inflammatory pain in an integrated manner. These findings provide novel insights enabling the clinical application of acupuncture in the treatment of inflammatory diseases.

Immediate Analgesic Effect of Acupuncture in Patients With Primary Dysmenorrhea: A fMRI Study.

Primary dysmenorrhea (PDM) is a common gynecological disease characterized by lower abdominal pain. Acupuncture is considered a good alternative therapy for PDM. However, the central mechanism of the analgesic effect of acupuncture is largely unknown. In this study, eligible patients were randomized into the real and sham acupuncture groups using a computer-generated, permuted block randomization method. The study cohort comprised 34 patients: 19 in the real acupuncture group and 15 in the sham acupuncture group. The clinical characteristics of the patients during their menstrual period were collected, and imaging scans were performed during the first 3 days of the patients’ menstrual period. We analyzed task and resting functional magnetic resonance imaging (fMRI) data to investigate the potential central mechanism of the immediate effect of acupuncture intervention on the intensity of PDM pain. The task fMRI study found that the rostral anterior cingulate cortex (rACC) and right supplemental motor area were activated during real acupuncture. Using the resting-state functional connectivity (FC) method, we found a post- versus pre-treatment change in the FC of the rACC and left precentral gyrus in the comparison of real acupuncture versus sham acupuncture. In addition, the FC of the rACC–left precentral gyrus at baseline was negatively correlated with short-term analgesia, while the change in the FC of the rACC–left precentral gyrus was positively correlated with short-term analgesia after acupuncture treatment. These findings support the importance of rACC–left precentral gyrus resting-state FC in the modulation of the intensity of PDM pain through acupuncture, which may shed light on the central mechanism of acupuncture in the treatment of PDM.

An Hypothesis for CXCL1/CXCR2 Signaling Regulating Neutrophil-Derived Opioid Peptides Involved in Acupuncture for Inflammatory Pain

Increasing evidences demonstrate that acupuncture is effective in treating inflammatory pain. Recent studies have found that peripheral endogenous opioid peptides in the area of inflammation are involved in acupuncture-treating inflammatory pain. However, the source of endogenous opioid peptides in local area of inflammation and the mechanism of acupuncture regulating these opioid peptides remain unclear. Studies have demonstrated that neutrophils infiltrated in the inflamed tissue contain and release opioid peptides. Chemokine (C-X-C motif) ligand 1 (CXCL1) is one of the key neutrophil chemokines and can promote the blood neutrophil recruitment to the area of inflammation. In our previous experiments, we found that acupuncture could alleviate inflammatory pain and significantly increase the concentration of chemokine CXCL1 in the blood of rats with inflammatory pain. So we suppose that increased concentration of CXCL1 by acupuncture could activate the blood opioid-containing neutrophils via its main receptor chemokine receptor type 2 (CXCR2) and promote them recruit to the inflamed tissue to release opioid peptides, participating in the analgesic effect of acupuncture.

Chemokine CXCL1 in serum mediates the antinociceptive effect of manual acupuncture at ST36.

Inflammatory pain is the most common type of pain encountered clinically. The analgesic effect of acupuncture has been well-documented. The aim of this study was to investigate the involvement of chemokine CXCL1 in the serum on manual acupuncture (MA)-induced antinociception. Rats with inflammatory pain of the right hind paw were induced by intraplantar (i.pl.) administration of complete Freund's adjuvant (CFA). After wards, the CFA-injected rats were treated daily with MA at ST36 from Day 1 to Day 7, and thermal nociceptive thresholds (paw withdrawal latency; PWL) were analyzed. The concentration of CXCL1 in the serum of the rats was measured by enzyme-linked immunosorbent assay (ELISA) after the first and the last MA treatment. Subsequently, the rats were injected with two doses (5 or 10 μg) of recombinant CXCL1 through the tail vein daily from Day 1 to Day 7 or injected with two doses (6.4 or 16 μg) of anti-CXCL1 antibody using the same methods and course at 30 min before MA, and the PWLs were measured again. Finally, naloxone (500 μg, 0.1 mL) was administered by i.pl. injection into the inflamed paw 5 min before the last MA treatment or last injection of recombinant CXCL1. MA significantly increased the PWLs and upregulated the expression of serum CXCL1 in the CFA-injected rats. Without acupuncture, repeated tail vein injection of recombinant CXCL1 showed an analgesic effect on CFA-induced inflammatory pain. Conversely, the neutralization of serum CXCL1 by anti-CXCL1 antibody decreased MA-induced antinociception in a time-dependent manner. Anti-CXCL1 antibody injected just once before the first MA did not affect MA-induced antinociception. The analgesic effects of MA and recombinant CXCL1 were reversed by an i.pl. injection of naloxone. This study indicates MA at ST36 had an analgesic effect on inflammatory pain and found a novel function of CXCL1. Increased serum CXCL1 had an antinociceptive effect on inflammatory pain induced by CFA. CXCL1 in serum appeared to be a key molecule involved in the peripheral mechanism of MA-induced antinociception. The analgesic effect of MA or recombinant CXCL1 on inflammatory pain might be mediated through a peripheral opioid pathway, which needs further investigation.

Analgesic effect of acupuncture and dipyrone on toothache - an energetic analysis

Analgesic effect of acupuncture and dipyrone on toothache - an energetic analysis

High Temporal Summation of Pain Predicts Immediate Analgesic Effect of Acupuncture in Chronic Pain Patients-A Prospective Cohort Study.

Objectives: This prospective cohort study explored whether two distinguished sensory parameters predicted acupuncture effects in chronic pain patients; namely high temporal summation of pain (TS) indicating spinal synaptic facilitation as well as a low vibration detection threshold (VDT) indicating a loss of Aβ-fiber function.Methods: Pinprick induced TS and VDT were assessed by standardized, validated methods at the most painful body site and a pain free control site in 100 chronic pain patients receiving six acupuncture sessions as part of an interdisciplinary multimodal pain treatment (IMPT). Immediate change in pain intensity after the first acupuncture session (first treatment on the first day of IMPT) was assessed by the verbal rating scale (VRS, 0–100). After 4 weeks of treatment, patients indicated in a questionnaire whether acupuncture had relieved pain immediately and whether it had contributed to overall pain reduction and well-being after IMPT.Results: Logistic regression analysis revealed an association between high TS at the control site and a reduction in pain intensity of at least 30% (VRS) after the first acupuncture (OR [95%-CI] 4.3 [1.6–11.8]). Questionnaire ratings of immediate pain relief after acupuncture were associated with high TS at the control site (OR [95%-CI] 3.8 [1.4–10.2] any pain relief, OR [95%-CI] 5.5 [1.7–17.1] over 50% pain reduction) and at the pain site (OR [95%-CI] 3.2 [1.2–8.9] any pain relief). Appraisals of the contribution of acupuncture to overall pain reduction and well-being after IMPT were not associated with TS. The VDT was not associated with any outcome.Conclusion: This explorative study provides first-time evidence that high TS, especially at a pain free control site, but not VDT, might predict immediate analgesic response to acupuncture in chronic pain patients. Thus, highly centrally sensitized chronic pain patients might respond particularly well to acupuncture.

Influence of the Intensity, Components, and Spreading of the Deqi Sensation on the Analgesic Effect of SP6 Needling in Primary Dysmenorrhea Patients: A Secondary Analysis of a Randomised Controlled Trial.

Although deqi, the phenomenon whereby excitation of Qi in the meridians occurs with needling, is critical to the practice of acupuncture and its efficacy, it is poorly understood. So we investigate the influence of the deqi sensation on the analgesic effects of acupuncture in patients who were enrolled in a randomised controlled trial for the treatment of patients with primary dysmenorrhea, a painful and common condition, and cold and dampness stagnation. Two groups were assessed: a deqi group (undergoing deep needling with thick needles and manipulation, n=17) and a non-deqi group (undergoing shallow needling with thin needles and no manipulation, n=51). The Sanyinjiao (SP6) was needled for 30 min in both groups. Pain scores at baseline, upon needle removal, and at 10, 20, and 30 min after needle removal were evaluated by the Visual Analogue Scale for pain. The deqi sensation was evaluated by the Acupuncture Deqi Clinical Assessment Scale. Patients who experienced a genuine deqi sensation (n=39) were selected for further analysis. Compared with patients in the non-deqi group who experienced deqi (n=25), patients who self-reported deqi in the deqi group (n=14) felt a stronger deqi sensation, experienced soreness and fullness more frequently, felt a greater intensity of soreness, fullness, electric sensation, spreading, and radiating, and experienced larger spreading distances. In those who experienced the deqi sensation in the deqi group, the intensity of the sensation, as well as their degree of soreness and fullness, was negatively correlated with pain reduction. In patients who experienced the deqi sensation in the non-deqi group, deqi intensity was positively correlated with pain reduction, while soreness was negatively correlated with pain reduction. The distance of spreading was not correlated with pain reduction in either group. We found, in SP6 needling of patients with primary dysmenorrhea with cold and dampness stagnation, that a moderate deqi response predicted a prolonged analgesic effect better than a strong deqi response.

The anti-inflammatory effect of acupuncture and its significance in analgesia

In the mechanisms of acupuncture analgesia, an important aspect often overlooked is the anti-inflammatory effect of acupuncture, which is mainly attained through the self-limiting inflammatory response-inflammatory reflex and its regulation of hypothalamic-pituitary-adrenal(HPA) axis and autonomic nerve system (the vagus nerve and the sympathetic postganglionic fiber). The significance of anti-inflammatory effect of acupuncture in analgesia is manifested twofold: The first, inflammatory nociceptive pain is a major type of chronic pain. The second, neurogenic inflammation is the mechanism by which certain acupoints or acu-reflex points (ARPs) are formed at the body surface and have short-cut connections to the pathological focus. Selecting ARPs and applying appropriate sensory stimulation or local microtrauma (affected by different needling means or stimulation parameters), combined with low-frequency electrical stimulation or the vagus stimulation in the concha region, are helpful to strengthen the anti-inflammatory and analgesic effect of acupuncture.

The low-frequency BOLD signal oscillation response in the insular associated to immediate analgesia of ankle acupuncture in patients with chronic low back pain.

PurposeThe present study evaluated the modulation effect of a painless acupuncture technique, ankle acupuncture (AA), on resting-state functional change in patients with chronic low back pain (CLBP).Patients and methodsFourteen participants diagnosed with CLBP received AA and underwent one brain functional image scan after tactile stimulation and another one following the insertion of the needle. The needling sensations and clinical pain intensities were evaluated after the end of each functional image scan. The significance levels of Visual Analog Scales/Scores (VASs) before and after acupuncture were determined using paired t-test. The brain areas showing differences in the amplitude of low-frequency fluctuation (ALFF) and fractional ALFF (fALFF) between the two scans were identified. We also explored the relationship between mean ALFF values in brain areas identified and VAS scores based on Pearson correlation coefficient.ResultsA complete-case analysis was performed on 12 participants. Neither different needling sensations nor any local sensations during the two scans was found. The clinical findings indicated that the scores of VAS scores were significantly lower after AA intervention (P<0.001). Compared with those after tactile stimulation, ALFF decreased in the left insular and increased in the left precuneus and right precentral gyrus, and fALFF decreased in the left insular, during retaining of AA (corrected). Moreover, there was a positive correlation found between mean ALFF change in the left insular and that of VAS values (P<0.05).ConclusionThe present study demonstrated the low-frequency BOLD signal oscillation response in the left insular in brain activity was associated with an immediate analgesia of AA in patients with CLBP, which provides new insights into intrinsic connections between low-frequency brain signals and analgesic effects of acupuncture.

Participation of local exosomes of acupoints in the initiation of acupuncture analgesic effect

ObjectiveTo investigate the local initiation role of local exosomes of acupoints in acupuncture analgesic effect. MethodsThirty-two rats with adjuvant arthritis were randomly divided into model group (Group CFA), model + electroacupuncture group (Group EA), model + antagonist + electroacupuncture group (Group GW4869 + EA), and model + dimethyl sulfoxide + electroacupuncture group (Group DMSO + EA), with 8 rats in each group. The model rat s of adjuvant arthritis were prepared by intradermal injection of 0.1 mL of Freund's adjuvant complete into the metatarsal of the right posterior foot to induce inflammation. No intervention was given in Group CFA, while electroacupuncture was performed in the other three groups at “Zúsānlĭ (足三里 ST 36, bilaterally)” and “Huántiào (环跳 GB 30, bilaterally)” of the rats with the following electroacupuncture parameters: dilatational wave with a frequency of 2/10 Hz, an intensity of 5/10/15 (0.76/1.53/2.3 mA), a duration of 30 min, and an intensity increasing every 10 min. In Group DMSO + EA, DMSO (with a concentration of 0.2%, 50µL/acupoint) was injected at bilateral “ST 36” of the model rats one hour before electroacupuncture, while GW4869 (with a concentration of 3 mg/mL, 50µL/acupoint) was injected at bilateral ST 36 of the model rats one hour before electroacupuncture in Group GW4869 + EA. The paw withdrawal latency (PWL) was used as the therapeutic effect index. ResultsThe PWL of rats in each group at Hour 24 after modeling was significantly lower than that before modeling, indicating that the models were successfully established. After the electroacupuncture treatment, the PWL of rats showed an increasing trend in all groups. The PWL of Group GW4869 + EA (6.74 ± 1.09)s was lower than that of Group EA (7.72 ± 1.54)s on Day 1 after injection, but the difference was not statistically significant (P > 0.05). The PWL values of Group GW4869 + EA (7.72 ± 0.70)s, (7.87 ± 0.58)s were significantly lower than those of Group EA (9.96 ± 0.94)s, (9.66 ± 0.96)s (both P < 0.05) on Days 2 and 3 after injection, and the differences were statistically significant. ConclusionIt was preliminarily found that acupuncture analgesic effect was significantly reduced after local exosomes of acupoints were blocked, indicating that local exosomes of acupoints may be involved in the initiation process of acupuncture effect.