The Anti-Inflammatory Actions and Mechanisms of Acupuncture from Acupoint to Target Organs via Neuro-Immune Regulation

Research Hotspots and Trends on Acupuncture for Anti-Inflammation: A Bibliometric Analysis from 2011 to 2021

Purpose

We here explored the research status, research hotspots, and development trend of acupuncture against inflammation from both quantitative and qualitative aspects through bibliometrics.

Methods

We used CiteSpace and VOSviewer to analyze the literature about acupuncture against inflammation from 2011 to 2021 in the Web of Science Core Collection database by using a visual knowledge map.

Results

In total, 1479 articles were included, and the number of articles published each year exhibited an upward trend. The largest number of articles were published in China (661), followed by the United States (287) and South Korea (164). The most productive institution is Beijing University of Chinese Medicine (72), while the most influential institution is the Capital Medical University (0.28). Evidence-based Complementary and Alternative Medicine (131) is the journal that published most articles on the topic. Lin Yiwen is the most prolific author, and Borovikova L is the most influential co-cited author. The keywords that have burst in the last 2 years are inflammation and activation. The keywords with the highest frequency of use are electroacupuncture (EA), inflammation, and expression.

Conclusion

The number of publications on acupuncture for anti-inflammation research is rapidly increasing. China is a productive country, but the influence of centrality is poor. Research institutions are concentrated in universities, and the whole collaborative network needs to be strengthened. The anti-inflammatory mechanism of acupuncture is the main focus of research in this field. Regulation of immune cell balance by acupuncture may be a hot topic in mechanism research. At present, immune cells, vagus nerve, signal pathway, inflammatory corpuscles, cytokines and neurotransmitters are popular research topics. In the future, the basic research of acupuncture for anti-inflammation transformed into clinical practice may be a trend. EA and bee venom acupuncture may be promising research directions for acupuncture treatment for inflammatory diseases.

Research progress on the immunomodulatory mechanism of acupuncture in tumor immune microenvironment

With the constantly deeper understanding of individualized precision therapy, immunotherapy is increasingly developed and personalized. The tumor immune microenvironment (TIME) mainly consists of infiltrating immune cells, neuroendocrine cells, extracellular matrix, lymphatic vessel network, etc. It is the internal environment basis for the survival and development of tumor cells. As a characteristic treatment of traditional Chinese medicine, acupuncture has shown potentially beneficial impacts on TIME. The currently available information demonstrated that acupuncture could regulate the state of immunosuppression through a range of pathways. An effective way to understand the mechanisms of action of acupuncture was to analyze the response following treatment of the immune system. This research reviewed the mechanisms of acupuncture regulating tumor immunological status based on innate and adaptive immunity.

Research progress on acupuncture treatment in central nervous system diseases based on NLRP3 inflammasome in animal models

Central nervous system (CNS) disorders exhibit complex neurophysiological and pathological mechanisms, which seriously affect the quality of life in patients. Acupuncture, widely accepted as complementary and alternative medicine, has been proven to exert significant therapeutic effects on CNS diseases. As a part of the innate immune system, NLRP3 inflammasome contributes to the pathogenesis of CNS diseases via regulating neuroinflammation. To further explore the mechanisms of acupuncture regulating NLRP3 inflammasome in CNS diseases, our study focused on the effects of acupuncture on neuroinflammation and the NLRP3 inflammasome in vascular dementia, Alzheimer's disease, stroke, depression, and spinal cord injury. This study confirmed that the activation of NLRP3 inflammasome promotes the development of CNS diseases, and inhibiting the activation of NLRP3 inflammasome is a potential key target for the treatment of CNS diseases. In addition, it is concluded that acupuncture alleviates neuroinflammation by inhibiting the activation of the NLRP3 inflammasome pathway, thereby improving the progression of CNS diseases, which provides a theoretical basis for acupuncture to attenuate neuroinflammation and improve CNS diseases.

Modified Sipjeondaebo-tang (JAROTANG) for Henoch-Schonlein purpura nephritis (HSPN): Two case reports

INTRODUCTION

Henoch-Schönlein purpura (HSP) is a disease commonly manifesting purpura, joint pain, and gastrointestinal symptoms. It can lead to glomerulonephritis (Henoch-Schönlein purpura nephritis, HSPN), which is directly associated with mortality and progression to chronic kidney disease (CKD). While HSP occurs more commonly in children, deadly outcomes occur at a higher rate in adult patients. Previous studies have not reported effective treatment of HSPN by Western or traditional medicine. Here, we report two cases of adult HSPN patients treated with the herbal medicine Jarotang (JRT, modified Sipjeondaebo-tang, modified SJDBT).

CASE SUMMARY

Two female patients (Cases 1 and 2), who were 26 and 27 years old, respectively, came to visit us complaining mainly of cutaneous purpura. Both women were diagnosed with HSP, and the results of urinalysis indicated that the HSP had already progressed to renal involvement (3+ proteinuria with 3+ urine occult blood in case 1; 100-120 RBC/HPF with 2+ urine occult blood in Case 2). Both patients were given modified SJDBT in the name of JRT, with some herbs added to disperse and circulate stagnant qi, relieve indigestion, and clear heat. After treatment, patient 1 showed only a trace level of urine occult blood, with disappearance of purpura and proteinuria. Patient 2 showed complete remission of purpura and hematuria.

CONCLUSIONS

Modified SJDBT, namely, JRT was effective in treating 2 cases of adulthood HSP and subsequent nephritis. This may be due to the ability of this therapy to replenish qi and blood and/or its immunological effect on T cells. The medication can serve as an effective cure for HSPN.

Paper-Based Detection Device for Microenvironment Examination: Measuring Neurotransmitters and Cytokines in the Mice Acupoint

(1) Background: The medical practice of acupuncture involves the insertion of a specialized stainless needle into a specific body point, often called an acupoint, to initiate a perceived phenomenon of de-qi sensation. Therefore, the term “de-qi” describes bodily sensations experienced by the recipient during acupuncture, which may include feelings of soreness, heaviness, fullness, numbness, and migration. However, while acupuncture treatments reportedly result in acupoint activation and an increased release of neurotransmitters or cytokines, detecting these substances released into the acupoint microenvironment is often missed or delayed in clinical and basic practice. (2) Methods: To address this situation, we employed a paper-based enzyme-linked immunosorbent assay method to examine acupoint environmental changes using minute volumes of easily accessible acupoint fluids. (3) Results: Our results indicated that while levels of adenosine triphosphate (ATP), interleukin-1β, interleukin-6, glutamate, substance P, and histamine were all increased in the experimental group following electroacupuncture (EA) treatment, contrary results were observed in the sham EA and transient receptor potential vanilloid 1 (Trpv1^−/−) groups. Subsequently, TRPV1 and its associated molecules were augmented in mouse dorsal root ganglion, spinal cord, thalamus, and the somatosensory cortex, then examined by Western blotting and immunofluorescence techniques. Investigations revealed that these elevations were still unobserved in the sham EA or EA in the Trpv1^−/− groups. Furthermore, results showed that while administering ATP could mimic EA function, it could be reversed by the ATP P2 receptor antagonist, suramin. (4) Conclusions: Our data provide novel information, indicating that changes in neurotransmitter and cytokine levels can offer insight into acupuncture mechanisms and clinical targeting.

The application of acupuncture in cardiopathy: A bibliometric analysis based on Web of Science across ten recent years

Background

With high morbidity and mortality, cardiopathy is a major component of cardiovascular disease, causing a huge burden of disease to public health worldwide. In recent years, research on acupuncture treatment of cardiopathies has been increasing. However, no bibliometric analysis has been conducted to systematically describe the research progress and hotspots in this field. Therefore, this study aimed to conduct a bibliometric analysis of the relevant literature to explore the current status and future development of acupuncture for cardiopathies.

Methods

The Web of Science (WoS) Core Collection Database was searched for literature related to acupuncture therapies for cardiopathies from 2011 to 2021. Using CiteSpace 5.8 R3, cooperation network diagrams of authors, institutions, countries and journals, keyword co-occurrences, and clustering were performed and analyzed.

Results

A total of 321 studies were included. Overall, the number of annual publications increased yearly. These publications came from 31 countries or regions, of which China and the United States made the greatest contributions. In total, 333 authors from 258 institutions participated in this field, and Beijing University of Chinese Medicine and Professor Fanrong Liang were the most published institution and author, respectively. Evidence-based Complementary and Alternative Medicine published the largest number of articles, and CIRCULATION was the most commonly cited journal. Based on co-occurrences and cluster analysis of 257 keywords, three research frontiers and hotspots were identified: acupuncture for blood pressure regulation, acupuncture for coronary heart disease, and acupuncture for regulation of heart rate. In these three research frontiers, the rostral ventrolateral medulla (RVLM) and autonomic nervous system (ANS) are the most popular mechanisms.

Conclusion

A stable development trend has formed in this field. Further research should focus on the role of acupuncture therapies in the treatment of hypertension or hypertensive heart disease, coronary heart disease, and arrhythmia based on the mechanisms related to the RVLM and ANS.

Effects of Electroacupuncture on Gastrointestinal Motility Function, Pain, and Inflammation via Transient Receptor Potential Vanilloid 1 in a Rat Model after Colonic Anastomoses

Background. Complications after colon surgery are a major obstacle to postoperative recovery. The purpose of this study was to investigate the effect of electroacupuncture (EA) at Zusanli (ST36) on gastrointestinal motility in rats after colonic anastomosis and the mechanism of transient receptor potential vanillin 1 (TRPV1) channel in regulating gastrointestinal motility, pain, and inflammation. Methods. The rats were randomly divided into six groups, including the control, model, EA, sham-EA, capsaicin, and capsaicin+EA groups, with preoperative capsaicin pretreatment and EA treatment at ST36 acupoint after surgery. Rats were treated using EA at ST36 or sham acupoints after surgery for 5 days. Capsaicin was intraperitoneally injected into rats 3 hours before surgery. Gastrointestinal motility was assessed by measuring the gastric residue, small intestinal propulsion in vivo, contractile tension, and frequency of isolated muscle strips in vitro. The mechanical withdrawal threshold (MWT) of abdominal incision skin and spontaneous nociceptive scores were observed and recorded in rats after colon anastomosis. The expressions of TRPV1, substance P (SP), neurokinin 1 (NK1) receptor, nuclear factor kappa-B (NF-κB), interleukin- (IL-) 6, L-1β, and tumor necrosis factor- (TNF-) α were determined. Results. Compared with the model group, electroacupuncture at ST36 point could significantly reduce the residual rate of stomach in rats after operation and increase the propulsive force of the small intestine and the contraction tension of the isolated smooth muscle. Electroacupuncture also increased postoperative day 3 MWT values and decreased postoperative spontaneous nociception scores. In addition, electroacupuncture treatment downregulated the expressions of IL-6, IL-1β, TNF-α, TRPV1, NF-κB, SP, and NK1 receptors in the colon tissue of rats after colonic anastomosis. Conclusions. Our study showed that electroacupuncture at ST36 acupoint could improve gastrointestinal motility in rats after colonic anastomosis and relieve intestinal inflammation and pain. The mechanism may be to inhibit the activation of NF-κB and SP/NK1 receptor signaling pathways by inhibiting TRPV1.

Dopamine relieves inflammatory responses through the D2 receptor after electroacupuncture at ST36 in a mouse model of chronic obstructive pulmonary disease

OBJECTIVE

To detect the role of dopamine in the anti-inflammatory effect of electroacupuncture (EA) at ST36 in a mouse model of chronic obstructive pulmonary disease (COPD).

METHODS

Twenty-eight male BALB/c mice were randomly divided into the control group, model group, sham EA (sham) group or ST36 EA (ST36) group in a 1:1:1:1 ratio (n = 7 each). The COPD mouse model was established through cigarette smoke (CS) exposure for 12 weeks. During the last 2 weeks, EA was applied at a sham point location or ST36 before CS exposure. Lung function, histopathological changes, inflammatory cell counts in bronchoalveolar lavage fluid (BALF), inflammatory cytokines in BALF, plasma, lung tissue homogenate (LTH), and plasma dopamine levels were detected in the different groups. Furthermore, the role of different dopamine receptors was explored through intraperitoneal injections of non-specific dopamine receptor antagonist chlorpromazine, specific dopamine D1 receptor antagonist SCH 23390 and specific dopamine D2 receptor antagonist eticlopride hydrochloride prior to ST36 EA and CS exposure.

RESULTS

EA at ST36 improved lung function, alleviated lung and systemic inflammatory responses by reducing inflammatory cells and cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-8 and IL-1β in BALF, plasma and lung tissue in this COPD mouse model. Plasma dopamine was greatly increased after EA at ST36, negatively correlated with lung histological lesions and inflammatory cytokine levels, and positively correlated with mice body weight and lung function indicators. Chlorpromazine and eticlopride hydrochloride inhibited the anti-inflammatory effect of EA at ST36, while SCH 23390 showed no neutralizing effect.

CONCLUSION

EA at ST36 could alleviate inflammation in this mouse model of COPD through the dopamine D2 receptor pathway.

Enhanced Cognition and Neurogenesis in miR-146b Deficient Mice

The miR-146 family consists of two microRNAs (miRNAs), miR-146a and miR-146b, which are both known to suppress a variety of immune responses. Here in this study, we show that miR-146b is abundantly expressed in neuronal cells, while miR-146a is mainly expressed in microglia and astroglia of adult mice. Accordingly, miR-146b deficient (Mir146b-/-) mice exhibited anxiety-like behaviors and enhanced cognition. Characterization of cellular composition of Mir146b-/- mice using flow cytometry revealed an increased number of neurons and a decreased abundancy of astroglia in the hippocampus and frontal cortex, whereas microglia abundancy remained unchanged. Immunohistochemistry showed a higher density of neurons in the frontal cortex of Mir146b-/- mice, enhanced hippocampal neurogenesis as evidenced by an increased proliferation, and survival of newly generated cells with enhanced maturation into neuronal phenotype. No microglial activation or signs of neuroinflammation were observed in Mir146b-/- mice. Further analysis demonstrated that miR-146b deficiency is associated with elevated expression of glial cell line-derived neurotrophic factor (Gdnf) mRNA in the hippocampus, which might be at least in part responsible for the observed neuronal expansion and the behavioral phenotype. This hypothesis is partially supported by the positive correlation between performance of mice in the object recognition test and Gdnf mRNA expression in Mir146b-/- mice. Together, these results show the distinct function of miR-146b in controlling behaviors and provide new insights in understanding cell-specific function of miR-146b in the neuronal and astroglial organization of the mouse brain.

Clinical Efficacy and Potential Mechanisms of Acupoint Stimulation Combined With Chemotherapy in Combating Cancer: A Review and Prospects

Although chemotherapy is the first-line treatment strategy for a variety of tumors, its side effects have limited its efficacy. This review summarizes the progress on the use of acupoint stimulation to combat chemotherapy-associated side effects, including chemotherapy-induced peripheral neuropathy (CIPN), cognitive impairment (CICI), and gastrointestinal toxicity (GI), as well as myelosuppression and immunosuppression. It was found that acupoint stimulation attenuated CIPN and GI by modulating the 5-hydroxytryptamine system in dorsal root ganglia, the dorsal horn of the spinal cord, and the duodenum by reducing oxidative stress and neuroinflammation. Acupoint stimulation also alleviated GI by activating vagal activity in the nucleus tractus solitarius and promoting the secretion of gastrointestinal neuropeptide hormones. Acupoint stimulation restored both bone marrow hematopoiesis and immune function to combat cancer. In addition, the combination of acupoint stimulation and chemotherapy could inhibit tumor growth by promoting tumor cell apoptosis and the enrichment of chemotherapeutic agents in tumor tissue and by modulating the tumor immune microenvironment and normalizing the vasculature. Multiple evidence also indicates that neuroimmune regulation may be involved in the effects of acupoint stimulation. In conclusion, the evidence suggests that acupoint stimulation can alleviate the side effects of chemotherapy and can also assist chemotherapeutic agents in inhibiting tumor growth, which expands the clinical application of acupoint stimulation in cancer treatment. However, more high-quality clinical studies are needed to confirm the clinical value of acupoint stimulation.

Acupuncture improves the symptoms, intestinal microbiota, and inflammation of patients with mild to moderate Crohn's disease: A randomized controlled trial

BACKGROUND

The efficacy and mechanisms of acupuncture for Crohn's disease (CD) are not well understood. We investigated its effects on symptoms, intestinal microbiota, and circulating inflammatory markers in CD patients.

METHODS

This 48-week, randomized, sham controlled, parallel-group clinical trial was performed at a tertiary outpatient clinic in China. From April 2015 to November 2019, 66 patients (mean age 40·4, 62·1% were male, all were Han Chinese) with mild to moderate active CD and unresponsive to drug treatment were enrolled and randomly assigned equally to an acupuncture group or a sham group. The treatment group received 3 sessions of acupuncture plus moxibustion per week for 12 weeks and a follow-up of 36 weeks. Clinicaltrials.gov: NCT02559037.

FINDINGS

At week 12, the clinical remission rate (the primary outcome) and clinical response rate of acupuncture group were significantly higher than that of sham group, with a difference of 42·4% (95% CI: 20·1%-64·0%) and 45·5% (95% CI: 24·0%-66·9%), respectively, both of which maintained at week 48. The acupuncture group had significantly lower CD activity index and C-reactive protein level at week 12, which maintained at 36-week follow-up. The CD endoscopic index of severity, histopathological score, and recurrence rate at week 48 were significantly lower in acupuncture group. The number of operational taxonomic unit of intestinal microbiota and relative abundance of Faecalibacterium prausnitzii and Roseburia faecis were increased. Plasma diamine oxidase, lipopolysaccharide, and Th1/Th17 related cytokines were decreased in 12-week after acupuncture.

INTERPRETATION

Acupuncture was effective in inducing and maintaining remission in patients with active CD, which was associated with increased abundance of intestinal anti-inflammatory bacteria, enhanced intestinal barrier, and regulation of circulating Th1/Th17-related cytokines.

FUNDING

National Key Basic Research Program of China (2015CB554500 and 2009CB522900), Shanghai Rising-Star Program (19QA1408100).