Acupuncture-moxibustion in treating irritable bowel syndrome: How does it work?

Effectiveness and safety of acupuncture modalities for overweight and obesity treatment: a systematic review and network meta-analysis of RCTs

Introduction

The effectiveness and safety of acupuncture in the treatment of obesity have not been assessed. This poses a challenge for clinicians who choose to use acupuncture in the treatment of obesity, as they are unable to prioritize this approach based on outcome variables.

Methods

In May 2024, a literature search of five databases was conducted. Only randomized controlled trials evaluating body weight (BW), body mass index, waist circumference (WC), and adverse events in patients with a body mass index (BMI) of 25 or higher for various acupuncture modalities were included. The risk of bias was assessed using the Cochrane risk-of-bias tool for randomized trials, version 2. Pairwise meta-analysis (PMA) and Bayesian network meta-analysis (NMA) were performed using a random effects model for quantitative synthesis.

Results

Fourteen studies (n = 868) were included. The included studies evaluated the following acupuncture modalities: electroacupuncture (EA) (N = 6), laser acupuncture (LA) (N = 2), auricular acupuncture (AA) (N = 5), and manual acupuncture (MA) (N = 3). The PMA found that adding EA to usual care (UC), compared to UC alone, reduced BW (MD = 2.46, 95% CI = 1.12 to 3.80, I 2 = 58%, REM, N = 3, n = 157). The NMA of BW showed the following effect sizes for UC alone versus each acupuncture modality combined with UC: LA (MD = 2.09, 95% CI = 0.04 to 3.86), EA (MD = 2.04, 95% CI = 0.88 to 3.50), AA (MD = 1.69, 95% CI = -0.11 to 3.58), and MA (MD = 1.02, 95% CI = -0.82 to 2.94). The probability of each modality being the optimal treatment was evaluated using the surface under the cumulative ranking curve. EA was the most efficacious for BW and BMI, while LA was the most efficacious for WC.

Discussion

EA and LA can effectively complement clinical obesity management. The number of included studies was limited, and publication bias may have occurred, necessitating a cautious interpretation of the results. Furthermore, most studies lasted between six and 12 weeks. Future clinical studies of acupuncture for obesity should include longer follow-up periods.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=387788, identifier CRD42023387788.

Electroacupuncture protects the intestinal mucosal barrier in diarrhea-predominant Irritable Bowel Syndrome rats by regulating the MCs/Tryptase/PAR-2/MLCK pathway

OBJECTIVE

The pathogenesis of diarrhea-predominant irritable bowel syndrome (IBS-D) is related to damage to the intestinal mucosal barrier function. Based on the Mast cell (MC)/Tryptase/Protease-activated receptor-2 (PAR-2)/Myosin light chain kinase (MLCK) pathway, this study explored the effect of electroacupuncture (EA) on IBS-D rats and its possible mechanism of protecting the intestinal mucosal barrier.

METHODS

The IBS-D rat model was established by mother-offspring separation, acetic acid enema, and chronic restraint stress. The efficacy of EA on IBS-D rats was evaluated by observing the rate of loose stool (LSP) and the minimum volume threshold of abdominal withdrawal reflex (AWR) in rats. Mast cells and the ultrastructure of intestinal mucosa were observed by H&E staining, toluidine blue staining, and transmission electron microscopy. The expression levels of Tryptase, PAR-2, MLCK, zonula occludens-1 (ZO-1), and Occludin in rats were detected by ELISA, qRT-PCR, and western blot.

RESULTS

After 7 days of intervention, compared to the IBS-D group, the loose stool rates of rats in IBS-D + EA group and IBS-D + ketotifen group were decreased (P < 0.01), the minimum volume thresholds of AWR were improved (P < 0.01), the inflammation of colon tissue decreased, the number of MCs were decreased (P < 0.01), the expression of Tryptase, PAR-2, and MLCK were lowered (P < 0.01, P < 0.05), and the expression of ZO-1 and Occludin were enhanced (P < 0.01, P < 0.05). Compared to the EA group, there was no significant difference in each index between the ketotifen groups (P > 0.05).

CONCLUSION

EA has a good therapeutic effect on IBS-D rats. Regulating the MCs/Tryptase/PAR-2/MLCK pathway may be a mechanism to protect the intestinal mucosal barrier.

The Gut-Liver-Brain Axis: From the Head to the Feet

The gut-liver-brain axis, a multifaceted network of communication, intricately connects the enteric, hepatic, and central nervous systems [...].

Acupuncture for postoperative gastrointestinal dysfunction in cancer: a systematic review and meta-analysis

Background

Postoperative gastrointestinal dysfunction (PGD) in cancer is the commonest and most severe postoperative complication in patients with cancer. Acupuncture has been widely used for PGD in cancer. This study aimed to evaluate the efficacy and safety of acupuncture for PGD in cancer.

Methods

We comprehensively searched eight randomised controlled trials (RCTs) of acupuncture for PGD in cancer published until November 2022. Time to first flatus (TFF) and time to first defecation (TFD) were the primary outcomes, and time to bowel sound recovery (TBSR) and the length of hospital stay (LOS) were the secondary outcomes. The Cochrane Collaboration Risk of Bias Tool was used to assess the quality of the RCTs, and the Grading of Recommendations Assessment, Development, and Evaluations (GRADE) system was used to evaluate the certainty of the evidence. The meta-analysis was performed using RevMan 5.4, and a publication bias test was performed using Stata 15.1.

Results

Sixteen RCTs involving 877 participants were included in this study. The meta-analysis indicated that acupuncture could effectively reduce the TFF, TFD, and TBSR compared with routine treatment (RT), sham acupuncture, and enhanced recovery after surgery (ERAS). However, acupuncture did not shorten the LOS compared with RT and ERAS. The subgroup analysis revealed that acupuncture could significantly reduce the TFF and TFD. Acupuncture effectively reduced the TFF and TFD in all cancer types included in this review. Besides, local acupoints in combination with distal acupoints could reduce the TFF and TFD, and distal-proximal acupoints could significantly reduce the TFD. No trial reported adverse events of acupuncture.

Conclusions

Acupuncture is an effective and relatively safe modality for treating PGD in cancer. We anticipate that there will be more high-quality RCTs involving more acupuncture techniques and cancer types, focusing on combining acupoints for PGD in cancer, further determining the effectiveness and safety of acupuncture for PGD in patients with cancer outside China.

Systematic review registration

https://www.crd.york.ac.uk/prospero, identifier CRD42022371219.

The immunomodulatory mechanisms for acupuncture practice

The system physiology approaches that emerge in western countries in recent years echo the holistic view of ancient Traditional Chinese Medicine (TCM) practices that deal with the root, rather than only the symptoms of diseases. Particularly, TCM practices, including acupuncture, emphasize the mobilization of self-healing mechanisms to bring back body homeostasis. Acupuncture has been practiced for over two thousand years to modulate body physiology via stimulation at specific body regions (acupoints). With the development of various research on acupuncture therapy, its regulatory effect on the immune system has been gradually recognized, especially on immunological diseases, including infectious and allergic diseases. In this study, we reviewed the immunomodulatory mechanism of acupuncture and systematically integrates existing research to respectively elucidate the modulatory mechanisms of acupuncture on the innate immune system, adaptive immune system, and well-known neuroanatomical mechanisms, including intact somatosensory-autonomic reflex pathway. With the advances made in recent systems physiology studies, we now have a great opportunity to gain insight into how acupuncture modulates immunity, and subsequently improves its efficacy.

Acupuncture vs. antispasmodics in the treatment of irritable bowel syndrome: An adjusted indirect treatment comparison meta-analysis

Background: Acupuncture has been extensively applied to manage irritable bowel syndrome (IBS) in clinical practice in China. Some randomized controlled trials (RCTs) have demonstrated their efficacy, but it has rarely been compared with first-line antispasmodics to verify their effectiveness. Therefore, we compare acupuncture with antispasmodics in the treatment of IBS by using an adjusted indirect treatment comparison meta-analysis.

Methods: Embase, OVID Medline, and the Cochrane Central Register of Controlled Trials databases were searched from inception to 14 March 2022, with no language restrictions. RCTs comparing antispasmodics or acupuncture with placebo or one of the antispasmodics were enrolled. The primary outcome of interest was the improvement of abdominal pain. And the secondary outcomes of interest were the relief of global IBS symptoms and adverse events. The random-effects model was utilized to pool data. The effect size was measured by standardized mean difference (SMD) or relative ratio, and the effectiveness of acupuncture and different antispasmodics were ranked by P-scores.

Results: Thirty-five RCTs (n = 5,190) were included. The analysis showed that cimetropium, drotaverine, acupuncture, and pinarverium were superior over placebo in relieving abdominal pain; cimetropium (SMD, −3.00 [95%CI, −4.47 to −1.53], P-score = 0.99) ranked the most effective. In pairwise comparisons, acupuncture had a greater improvement than most antispasmodics except cimetropium and drotaverine in relieving abdominal pain, although the between-group difference was statistically insignificant. In the analysis of continuous outcome in the relief of global IBS symptoms, the result showed that pinaverium was more effective (SMD, 1.72 [95%CI, 0.53 to 2.92], P-score = 0.90) than placebo. Trimebutine and acupuncture had greater improvements than placebo, but no significant difference was shown between groups. In pairwise comparisons, acupuncture was more effective than pinaverium (SMD, −1.11 [95%CI, −1.94 to −0.28]) in relieving global IBS symptoms. In the analysis of adverse events, acupuncture had a lower adverse event rate than most of the other antispasmodics.

Conclusion: Cimetropium, drotaverine, and acupuncture were all better than placebo in improving abdominal pain. Acupuncture was preferred over pinaverium in relieving global IBS symptoms, and acupuncture had lower adverse events than most antispasmodics.

Ameliorating effects of electroacupuncture on the low-grade intestinal inflammation in rat model of diarrhea-predominant irritable bowel syndrome

BACKGROUND AND AIM

We aim to investigate the effects and mechanisms of electroacupuncture (EA) at ST25 and ST37 on the intestinal low-grade inflammation (LGI) in rat model of Diarrhea-predominant irritable bowel syndrome (IBS-D).

METHODS

IBS-D model rats were established by acetic acid enema combined with restraint and tail clamping. Before EA intervention, they were divided into three groups: blank 1 group, blank 2 group, and IBS-D model group. Diarrhea symptoms and visceral pain sensitivity were evaluated. After constructed the model successfully, the remaining IBS-D model group rats were randomly divided into model group and EA group. Local intestinal inflammation (HE staining), changes of intestinal mucosa (occludin protein and microvascular diameter) were evaluated. Differences between two groups were compared using t-test or Mann-Whitney U-test. Differences among more than two groups were compared using one-way ANOVA or Kruskal-Wallis test.

RESULTS

After modeling, the results of HE staining in intestinal tract of IBS-D model rats showed LGI. Compared with the model group, 4 h fecal moisture content (diarrhea index) and the AWR score were decreased in the EA group. The results of HE in EA group showed that the infiltration of intestinal inflammatory cells were alleviated. Additionally, EA significantly upregulated the expression of occludin protein and partially dilated the intestinal microvascular diameter. Pearson correlation analysis showed that the symptoms of IBS-D rats were correlated with the changes of intestinal mucosa.

CONCLUSION

EA may treat intestinal LGI in IBS-D rats by upregulating the expression of occludin protein and dilating the intestinal microvascular diameter.

Effect of acupuncture for diarrhea-predominant irritable bowel syndrome: study protocol for a randomized clinical trial

Background

Diarrhea-predominant irritable bowel syndrome (IBS-D) is the most common subtype of IBS. Acupuncture is commonly used to treat IBS-D, but its effect is uncertain because of the poor quality of prior studies. This trial aims to evaluate the efficacy and safety of acupuncture treatment for IBS-D through comparisons with sham acupuncture.

Methods/design

This is a large-scale, multi-center, randomized, two-arm interventional clinical trial. Participants will take part in a total of 20 weeks of study, which contained 3 phases: 2-week screening, 6-week treatment, and 12-week follow-up. Based on the composite response rate of the primary endpoint in our pilot study (a sham acupuncture response rate of 27% and a true acupuncture of approximately 45%), 280 randomly allocated participants were planned. Eligible participants will be randomly assigned to the true acupuncture group and sham acupuncture group according to a ratio of 1:1, and a total of 15 sessions of treatment overall 6-week treatment period will be brought. The primary endpoint is a composite response rate at week 6, and the responder is defined as who responses in both abdominal pain intensity and stool consistency. Furthermore, composite response rates at other weeks, IBS Symptom Severity Scale, IBS Quality of Life, Adequate Relief scale, and individual IBS symptoms (abdominal pain, bloating, stool frequency) are chosen as secondary endpoints.

Discussion

This trial may provide high-quality evidence for the efficacy and safety of acupuncture in the treatment of IBS-D. The results of this study will be published in peer-reviewed journals.

Trial registration

Chinese Clinical Trial Registry: ChiCTR2100044762. Registered on 26 March 2021.

Effectiveness and safety of acupuncture for postoperative ileus following gastrointestinal surgery: A systematic review and meta-analysis

Background

Postoperative ileus (POI) is an important complication of gastrointestinal (GI) surgery. Acupuncture has been increasingly used in treating POI. This study aimed to assess the effectiveness and safety of acupuncture for POI following GI surgery.

Methods

Seven databases (PubMed, Embase, the Cochrane Library, China National Knowledge Infrastructure, Wan fang Data, VIP Database for Chinese Technical Periodicals, and Chinese Biomedical Literature Database) and related resources were searched from inception to May 30, 2021. Randomized controlled trials (RCTs) reporting the acupuncture for POI in GI were included. The quality of RCTs was assessed by the Cochrane Collaboration Risk of Bias tool, and the certainty of the evidence was evaluated by the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. A meta-analysis was performed by using RevMan 5.4 software.

Results

Eighteen RCTs involving 1413 participants were included. The meta-analysis showed that acupuncture could reduce the time to first flatus (TFF) (standardized mean difference [SMD] = −1.14, 95% confidence interval [CI]: −1.54 to −0.73, P < 0.00001), time to first defecation (TFD) (SMD = −1.31, 95% CI: −1.88 to −0.74, P < 0.00001), time to bowel sounds recovery (TBSR) (SMD = −1.57, 95% CI: −2.14 to −1.01, P < 0.00001), and length of hospital stay (LOS) (mean difference [MD] = −1.68, 95% CI: −2.55 to −0.80, P = 0.0002) compared with usual care. A subgroup analysis found that acupuncture at distal acupoints once daily after surgery had superior effects on reducing TFF and TFD. A sensitivity analysis supported the validity of the finding. Acupuncture also manifested an effect of reducing TFF, TFD and TBSR compared with sham acupuncture but the result was not stable. Relatively few trials have reported whether adverse events have occurred.

Conclusions

Acupuncture showed a certain effect in reducing POI following GI surgery with very low-to-moderate quality of evidence. The overall safety of acupuncture should be further validated. More high-quality, large-scale, and multicenter original trials are needed in the future.

Mild moxibustion for Irritable Bowel Syndrome with Diarrhea (IBS-D): A randomized controlled trial

ETHNOPHARMACOLOGICAL RELEVANCE

Moxibustion therapy is a traditional Chinese medicine external treatment method, which involves crushing dried herb Artemisia argyi H. Lév. & Vanio and rolling it into a long cigarette-like strip, igniting it and using its warmth to stimulate specific acupuncture points for a certain period of time. It is often used in Asia to treat various diseases, especially abdominal pain. Clinical reports suggest that acupuncture and moxibustion are the effective treatment for Irritable Bowel Syndrome with Diarrhea (IBS-D). However, there is no placebo-controlled study to prove its safety and efficacy.

OBJECTIVE

To evaluate the effects of mild moxibustion (MM) for the treatment of irritable bowel syndrome with diarrhea (IBS-D) through comparisons with those of placebo moxibustion.

PATIENTS AND METHODS

This was a single-site, randomized controlled trial was conducted at Shanghai Research Institute of Acupuncture and Meridian in China and enrolled 76 participants who met the Rome IV diagnostic criteria for IBS-D between May 2017 and December 2019. 76 participants were randomized to either mild moxibustion (MM) or placebo moxibustion group (PM) in a 1:1 ratio. 18 sessions of MM or PM were implemented over the course of 6 weeks (3 times per week). The primary outcome was adequate relief after 6 weeks of treatment.

RESULTS

Of 76 patients with IBS-D who were randomized (38 in the MM group and 38 in the PM group) were included in the intention-to-treat (ITT) analysis set. After treatment at week 6, the response rate was significantly higher in the MM group than the PM group (81.58% vs. 36.84%) with an estimated difference of 44.74 (95% CI, 23.46 to 66.02, P < 0.001). No participant reported severe adverse effects.

CONCLUSION

The findings suggest that mild moxibustion may be more effective than placebo moxibustion for the treatment of IBS-D, with effects lasting up to 12 weeks.

TRIAL REGISTRATION

ChiCTR, ChiCTR2100046852. Registered 29 May 2021 - Retrospectively registered, URL: http://www.chictr.org.cn/showproj.aspx?proj=127000.

The herbal preparation STW 5 affects serotonergic pathways in the brain and colon as well as stress parameters in experimental irritable bowel syndrome

BACKGROUND

Exposure to stress has been related to disturbance in 5-hydroxytryptamine (5-HT) signaling in the brain-gut axis and is considered as a major predisposing factor for the development of irritable bowel syndrome (IBS). The present study aimed to investigate the possible involvement of 5-HT and some other stress-related parameters in the effectiveness of STW 5 against stress-induced IBS.

METHODS

Rats were subjected to restraint stress (RS) for 1 h/day for 14 consecutive days to induce IBS-like symptoms and were given STW 5 orally at the same time. At the end of the experiment, blood samples were withdrawn, then animals were euthanized and the brain hippocampi, cerebral cortices, as well as colons were isolated for biochemical and histopathological assessments.

RESULTS

RS increased the plasma corticotrophin releasing factor (CRF) with concomitant increase in hippocampal and cortical 5-HT levels, as well as mast cell inflammatory mediators, oxidative stress biomarkers, and histopathological inflammatory changes observed in rat colon. It also decreased the colonic content of 5-HT with consequent decrease in fecal pellet output (FPO). Treatment with STW 5 protected against these changes.

CONCLUSION

The protective effect of STW 5 against RS-induced IBS is related to its ability to normalize the induced changes in 5-HT in the brain-gut axis and counteract the stress-induced oxidative stress and inflammation.

Electroacupuncture Alleviates Visceral Hypersensitivity in IBS-D Rats by Inhibiting EGCs Activity through Regulating BDNF/TrkB Signaling Pathway

Objective

To determine whether electroacupuncture (EA) could alleviate visceral hypersensitivity in diarrhea-predominant irritable bowel syndrome (IBS-D) rats by inhibiting EGCs activity via the BDNF/TrkB signaling pathway.

Methods

Sprague Dawley rats were randomly divided to a control group (n = 8) and a model preparation group (n = 32), which received Senna solution by gavage and CUMS (chronic unpredictable mild stress) for 14 consecutive days and was further divided to a Model group, an EA group (only electroacupuncture), an EA + TrkB agonist group (electroacupuncture and TrkB), and an EA + DMSO group (electroacupuncture and DMSO, n = 8 for each). Rats in the three EA groups were acupunctured at ST25, ST36, and LR3 for 20 min every day for 14 days. Abdominal withdrawal reflex (AWR) was used to quantify visceral sensitivity; reverse transcription polymerase chain reaction (RT-PCR) and double immunofluorescent staining were used to detect the colocalized expression of GFAP/BDNF and GFAP/TrkB. Western Blot (WB) was used to detect the expression of PLC and SP in the colon. Flow cytometry was used to detect the expression of Ca²⁺.

Results

EA effectively alleviated visceral hypersensitivity in IBS-D rats (P < 0.05). Compared to the control group, the expression of BDNF, TrkB, PLC, SP, and Ca²⁺ and the colocalized expression of GFAP/BDNF and GFAP/TrkB increased in the Model group (P < 0.05), while all these parameters decreased in the EA group following EA intervention (P < 0.05). In addition, no significant difference was found between the EA + TrkB agonist group and the control group (P > 0.05).

Conclusions

EA alleviates visceral hypersensitivity of IBS-D rats possibly by inhibiting the activity of EGCs through the BDNF/TrkB-PLC-Ca²⁺ signaling pathway in the colon.

Quality of Evidence Supporting the Role of Acupuncture for the Treatment of Irritable Bowel Syndrome

Objectives

To systematically collate, appraise, and synthesize the current evidence on acupuncture for irritable bowel syndrome (IBS).

Methods

Systematic reviews (SRs)/meta-analyses (MAs) of acupuncture for IBS were searched in eight databases. For quality evaluation of the enrolled studies, Assessment of Multiple Systematic Reviews 2 (AMSTAR-2) was used for methodological quality, Preferred Reporting Item for Systematic Reviews and Meta-Analyses (PRISMA) for reporting quality, and Grading of Recommendations Assessment, Development, and Evaluation (GRADE) for evidence quality.

Results

Ten studies were included in our review. According to AMSTAR-2, only one study met all the criteria and was rated as high methodological quality, and the rest were rated as low or very low methodological quality. According to the PRISMA checklist, most of the items were fully reported, with the exception of Q5 (protocol and registration), Q8 (search), and Q27 (funding). With the GRADE system, no outcome measure was rated as high quality.

Conclusions

Acupuncture may be a promising therapy for IBS. However, this conclusion must be treated with caution since the quality of SRs/MAs providing evidence is generally low.

Transcutaneous Electrical Acustimulation Improved the Quality of Life in Patients With Diarrhea-Irritable Bowel Syndrome

BACKGROUND AND AIM

Patients with diarrhea-dominant irritable bowel syndrome (IBS-D) experience abdominal pain and reduced quality of life and need effective treatments. This study aimed to evaluate whether transcutaneous electrical acustimulation (TEA) at two acupuncture points, LI4 and ST36, could improve pain and quality of life of patients with IBS-D.

MATERIALS AND METHODS

A total of 42 patients with IBS-D who met the Rome IV criteria were randomly divided into two groups: TEA and sham-TEA. TEA was performed through acupoints Hegu (LI4) and Zusanli (ST36) for one hour twice daily for one month, using previously established parameters; sham-TEA was delivered in the same way as TEA but without actual electrical current stimulation.

RESULTS

The sham-TEA group showed a significantly higher rate of drop-out than the TEA group (29% vs 0%, p = 0.021). TEA, but not sham-TEA, significantly improved quality of life (before: 78.55 ± 9.62, after: 85.97 ± 9.49, p < 0.0001). Both TEA and sham-TEA reduced abdominal pain; however, TEA was more potent than sham-TEA (p = 0.014). The IBS symptom severity scale score was reduced by both TEA and sham-TEA. Autonomic functions assessed by plasma norepinephrine and pancreatic polypeptide were not altered with TEA, nor was interleukin 10 or interleukin 6.

CONCLUSIONS

TEA at LI4 and ST36 improves abdominal pain and quality of life of patients with IBS-D, probably mediated by mechanisms other than autonomic function or inflammatory cytokines.

Acupuncture for Primary Dysmenorrhea: A Potential Mechanism from an Anti-Inflammatory Perspective

The low adverse effects of acupuncture for primary dysmenorrhea (PD), known as one of the most commonly reported gynecological debilitating conditions affecting women's overall health, have been thus far confirmed. Moreover, it has been increasingly recognized that inflammation is involved in such menstrual cramps, and recent studies have further shown that the anti-inflammatory effects of acupuncture are helpful in its control. This review portrays the role of inflammation in PD pathophysiology, provides evidence from clinical and animal studies on acupuncture for inflammation-induced visceral pain, and reflects on acupuncture-related therapies for dysmenorrhea with regard to their anti-inflammatory characteristics. Further research accordingly needs to be carried out to clarify the effects of acupuncture on proinflammatory factors in PD, particularly chemokines and leukocytes. Future studies on this condition from an anti-inflammatory perspective should be also performed in line with the notion of emphasizing stimulation modes to optimize the clinical modalities of acupuncture. Additionally, the effects and mechanism of more convenient self-healing approaches such as TENS/TEAS for PD should be investigated.

Treatment of Irritable Bowel Syndrome by Chinese Medicine: A Review

Irritable bowel syndrome (IBS) is a common refractory disease. Chinese medicine (CM) has remarkable efficacy and advantages on the treatment of IBS. This review summarized the articles focusing on the treatment of IBS with CM to sum up the latest treatment methods for IBS and the underlying mechanisms. Literature analysis showed that prescriptions, acupuncture, and moxibustion are the primary methods of CM treatment for IBS. The potential mechanism centers on the regulation of the enteric nervous system, the alleviation of visceral hypersensitivity, the stability of intestinal flora, and the regulation of the immune system.

Role of gut microbiota via the gut-liver-brain axis in digestive diseases

The gut-brain axis is a bidirectional information interaction system between the central nervous system (CNS) and the gastrointestinal tract, in which gut microbiota plays a key role. The gut microbiota forms a complex network with the enteric nervous system, the autonomic nervous system, and the neuroendocrine and neuroimmunity of the CNS, which is called the microbiota-gut-brain axis. Due to the close anatomical and functional interaction of the gut-liver axis, the microbiota-gut-liver-brain axis has attracted increased attention in recent years. The microbiota-gut-liver-brain axis mediates the occurrence and development of many diseases, and it offers a direction for the research of disease treatment. In this review, we mainly discuss the role of the gut microbiota in the irritable bowel syndrome, inflammatory bowel disease, functional dyspepsia, non-alcoholic fatty liver disease, alcoholic liver disease, cirrhosis and hepatic encephalopathy via the gut-liver-brain axis, and the focus is to clarify the potential mechanisms and treatment of digestive diseases based on the further understanding of the microbiota-gut- liver-brain axis.

Transcutaneous electrical acupuncture stimulation (TEAS) for gastrointestinal dysfunction in adults undergoing abdominal surgery: study protocol for a prospective randomized controlled trial

BACKGROUND

Postoperative gastrointestinal (GI) dysfunction (PGD) is a common problem after abdominal surgery. PGD can increase the length of hospital stay and may lead to serious complications. Acupuncture and moxibustion are alternative therapies for PGD that have been used in some settings. However, the effect of preventive application of acupuncture or transcutaneous electrical acupuncture stimulation (TEAS) is still uncertain. The purpose of this study is to investigate the efficacy of the continuous application of TEAS on GI function recovery in adults undergoing abdominal surgery. At the same time, we will try to confirm the mechanism of TEAS through the brain-gut axis.

METHODS/DESIGN

This study is a prospective, single-center, two-arm, randomized controlled trial that will be performed in a general hospital. In total, 280 patients undergoing abdominal surgery were stratified by type of surgery (i.e. gastric or colorectal procedure) and randomized into two treatment groups. The experimental group will receive TEAS stimulation at L14 and PC6, ST36 and ST37. The sham group will receive pseudo-TEAS at sham acupoints. The primary outcome will be the time to the first bowel motion by auscultation. The recovery time of flatus, defecation, the changes in perioperative brain-intestinal peptides, postoperative pain, perioperative complications, and hospitalization duration will be the secondary outcomes.

DISCUSSION

The results of this study will demonstrate that continuous preventive application of TEAS can improve the GI function recovery in patients undergoing abdominal surgery and that this effect may act through brain-gut peptides.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR1900023263 . Registered on 11 May 2019.

Central and Peripheral Mechanism of Acupuncture Analgesia on Visceral Pain: A Systematic Review

Background/Aims

Despite the wide use of acupuncture for the management of visceral pain and the growing interest in the pathophysiology of visceral pain, there is no conclusive elucidation of the mechanisms behind the effects of acupuncture on visceral pain. This systematic review aims to provide an integrative understanding of the treatment mechanism of acupuncture for visceral pain.

Methods

Electronic and hand searches were conducted to identify studies that involved visceral pain and acupuncture.

Results

We retrieved 192 articles, out of which 46 studies were included in our review. The results of our review demonstrated that visceral pain behaviors were significantly alleviated in response to acupuncture treatment in groups treated with this intervention compared to in sham acupuncture or no-treatment groups. Changes in the concentrations of β-endorphin, epinephrine, cortisol, and prostaglandin E2 in plasma, the levels of c-Fos, substance P, corticotropin-releasing hormone, P2X3, acetylcholinesterase (AchE), N-methyl-D-aspartate (NMDA) receptors, and serotonin in the gut/spinal cord, and the neuronal activity of the thalamus were associated with acupuncture treatment in visceral pain.

Conclusions

Acupuncture reduced visceral pain behavior and induced significant changes in neuronal activity as well as in the levels of pain/inflammation-related cytokines and neurotransmitters in the brain-gut axis. Further researches on the thalamus and on a standard animal model are warranted to improve our knowledge on the mechanism of acupuncture that facilitates visceral pain modulation.

Electroacupuncture Alleviated Referral Hindpaw Hyperalgesia via Suppressing Spinal Long-Term Potentiation (LTP) in TNBS-Induced Colitis Rats

Although referred pain or hypersensitivity has been repeatedly reported in irritable bowel syndrome (IBS) patients and experimental colitis rodents, little is known about the neural mechanisms. Spinal long-term potentiation (LTP) of nociceptive synaptic transmission plays a critical role in the development of somatic hyperalgesia in chronic pain conditions. Herein, we sought to determine whether spinal LTP contributes to the referral hyperalgesia in colitis rats and particularly whether electroacupuncture (EA) is effective to alleviate somatic hyperalgesia via suppressing spinal LTP. Rats in the colitis group (induced by colonic infusion of 2,4,6-trinitrobenzenesulfonic acid, TNBS), instead of the control and vehicle groups, displayed evident focal inflammatory destruction of the distal colon accompanied not only with the sensitized visceromotor response (VMR) to noxious colorectal distension (CRD) but also with referral hindpaw hyperalgesia indicated by reduced mechanical and thermal withdrawal latencies. EA at Zusanli (ST36) and Shangjuxu (ST37) attenuated the severity of colonic inflammation, as well as the visceral hypersensitivity and referral hindpaw hyperalgesia in colitis rats. Intriguingly, the threshold of C-fiber-evoked field potentials (CFEFP) was significantly reduced and the spinal LTP was exaggerated in the colitis group, both of which were restored by EA treatment. Taken together, visceral hypersensitivity and referral hindpaw hyperalgesia coexist in TNBS-induced colitis rats, which might be attributed to the enhanced LTP of nociceptive synaptic transmission in the spinal dorsal horn. EA at ST36 and ST37 could relieve visceral hypersensitivity and, in particular, attenuate referral hindpaw hyperalgesia by suppressing the enhanced spinal LTP.

Expression and clinical significance of 5-HT and 5-HT3R in the intestinal mucosa of patient with diarrhea-type irritable bowel syndrome

Expression levels and clinical significance of 5-HT and 5-HT₃R in the intestinal mucosa tissue of patients with diarrhea-type irritable bowel syndrome (D-IBS) were investigated. A retrospective analysis was performed on 46 tissue specimens (observation group) of the intestinal mucosa of patients with D-IBS, who were diagnosed in the Tongde Hospital of Zhejiang Province and received colonoscopy from March 2016 to December 2017, and 18 tissue specimens (control group) of the intestinal mucosa of healthy subjects who received physical examinations. The expression levels of 5-HT and 5-HT₃R in the intestinal mucosa tissue of patients in the observation and control group were detected by ELISA, and the relationship between 5-HT, 5-HT₃R and the clinicopathological parameters of patients with D-IBS was analyzed. Pearson's correlation analysis was used to analyze the correlation of 5-HT and 5-HT₃R in the intestinal mucosa tissue of patients with D-IBS. The expression levels of 5-HT and 5-HT₃R in the intestinal mucosa tissue of patients in the observation group were significantly higher than those of the patients in the control group (344.86±67.52 ng/ml and 13.04±8.34 pg/ml) (P<0.001). There was a positive correlation between the expression level of 5-HT and the expression level of 5-HT₃R in the intestinal mucosa tissue of patients with D-IBS (r=0.725, P<0.001). The expression levels of 5-HT and 5-HT₃R in the intestinal mucosa tissue of patients with D-IBS were both significantly higher than those of the healthy subjects. The expression levels of 5-HT and 5-HT₃R in patients with D-IBS were correlated with age, sex and the history of gastrointestinal infection. 5-HT and 5-HT₃R may be involved in the pathogenesis of D-IBS, and potentially used for clinical treatment.

Treatment of poststroke constipation with moxibustion: A case report

RATIONALE

Moxibustion, an important therapeutic measure of TCM, can stimulate acupoints to unblock the meridians and collaterals, regulate the function of qi and blood, support health, and expel pathogens. So it could be an effective and safe for the treatment of constipation and improvement of the quality of life in poststroke patients with constipation.

PATIENT CONCERNS

He has a history of constipation, with the defecation of hard, bound stool every 2 to 3 days with the help of glycerin enema.

DIAGNOSES

Constipation for >6 months; Cerebral infarction for 9 months; Type 2 diabetes for 3 years. Hypertension for approximately 1 month.

INTERVENTIONS

From the fifth day after admission, 5 rounds of moxibustion with moxa cones were administered at the bilateral ST25 and CV6 acupoints.

OUTCOMES

The patient successfully defecated within 1hour. Subsequently, the patient could maintain daily unobstructed defecation with a normal total stool weight and moderate hardness.

LESSONS

Moxibustion is effective and safe for the treatment of constipation and improvement of the quality of life in post-stroke patients with constipation.

Comparison of Electroacupuncture and Mild-Warm Moxibustion on Brain-Gut Function in Patients with Constipation-Predominant Irritable Bowel Syndrome: A Randomized Controlled Trial

OBJECTIVE

To compare the effects of electroacupuncture (EA) and mild-warm moxibustion (Mox) therapies for constipation-predominant irritable bowel syndrome (C-IBS) patients.

METHODS

Sixty C-IBS patients were assigned to 2 groups by simple randomized method, i.e. EA group (30 cases) and Mox group (30 cases). Both EA and Mox treatments were performed on bilateral Tianshu (ST 25) and Shangjuxu (ST 37) for 30 min each time, 6 times per week, for 4 consecutive weeks. The gastrointestinal symptoms and psychological symptoms of the two groups were scored before and after treatment. The effects on the corresponding functional brain areas, namely the anterior cingulate cortex (ACC), insular cortex (IC) and prefrontal cortex (PFC) were observed by functional magnetic resonance imaging (fMRI) before and after treatment.

RESULTS

Compared with the Mox group, greater improvements in abdominal distension, defecation frequency, diffificulty in defecation and stool features were observed in the EA group (all P<0.01), both Hamilton Anxiety Rating Scale and Hamilton Depression Rating Scale scores were signifificantly decreased in the EA group (all P<0.01). Finally, decreased activated voxel values were observed in the ACC, right IC and PFC brain regions of EA group with 150 mL colorectal distension stimulation (P<0.05 or P<0.01).

CONCLUSIONS

Both EA and Mox could signifificantly improve some of the most intrusive symptoms of C-IBS patients, and EA was more effective than Mox. The therapeutic effect of these two therapies might through modulating of the brain-gut axis function. (Registration No. ChiCTRTRC-11001349).

Irritable Bowel Syndrome

: Irritable bowel syndrome (IBS) is a common, chronic gastrointestinal (GI) condition characterized by disturbances in bowel habits and abdominal pain in the absence of known organic pathology. IBS reduces quality of life and is costly to treat. It is diagnosed using the symptom-based Rome criteria for functional GI disorders, which was recently updated and released as Rome IV. Both physiologic and psychological variables play a role in the etiology of IBS and perpetuate symptoms. Although research has shed light on IBS pathophysiology, therapeutic interventions remain symptom driven, employing both pharmacologic and nonpharmacologic approaches. Here, the authors review the epidemiology and pathophysiology of IBS, summarize diagnostic and treatment strategies, and discuss implications for nursing practice.

Neurobiological Mechanism of Acupuncture for Relieving Visceral Pain of Gastrointestinal Origin

It is currently accepted that the neural transduction pathways of gastrointestinal (GI) visceral pain include the peripheral and central pathways. Existing research on the neurological mechanism of electroacupuncture (EA) in the treatment of GI visceral pain has primarily been concerned with the regulation of relevant transduction pathways. The generation of pain involves a series of processes, including energy transduction of stimulatory signals in the sensory nerve endings (signal transduction), subsequent conduction in primary afferent nerve fibers of dorsal root ganglia, and transmission to spinal dorsal horn neurons, the ascending transmission of sensory signals in the central nervous system, and the processing of sensory signals in the cerebral cortex. Numerous peripheral neurotransmitters, neuropeptides, and cytokines participate in the analgesic process of EA in visceral pain. Although EA has excellent efficacy in the treatment of GI visceral pain, the pathogenesis of the disease and the analgesic mechanism of the treatment have not been elucidated. In recent years, research has examined the pathogenesis of GI visceral pain and its influencing factors and has explored the neural transduction pathways of this disease.

The Role of Visceral Hypersensitivity in Irritable Bowel Syndrome: Pharmacological Targets and Novel Treatments

Irritable bowel syndrome (IBS) is the most common disorder referred to gastroenterologists and is characterized by altered bowel habits, abdominal pain, and bloating. Visceral hypersensitivity (VH) is a multifactorial process that may occur within the peripheral or central nervous systems and plays a principal role in the etiology of IBS symptoms. The pharmacological studies on selective drugs based on targeting specific ligands can provide novel therapies for modulation of persistent visceral hyperalgesia. The current paper reviews the cellular and molecular mechanisms underlying therapeutic targeting for providing future drugs to protect or treat visceroperception and pain sensitization in IBS patients. There are a wide range of mediators and receptors participating in visceral pain perception amongst which substances targeting afferent receptors are attractive sources of novel drugs. Novel therapeutic targets for the management of VH include compounds which alter gut-brain pathways and local neuroimmune pathways. Molecular mediators and receptors participating in pain perception and visceroperception include histamine-1 receptors, serotonin (5-hydrodytryptamine) receptors, transient receptor potential vanilloid type I, tachykinins ligands, opioid receptors, voltage-gated channels, tyrosine receptor kinase receptors, protease-activated receptors, adrenergic system ligands, cannabinoid receptors, sex hormones, and glutamate receptors which are discussed in the current review. Moreover, several plant-derived natural compounds with potential to alleviate VH in IBS have been highlighted. VH has an important role in the pathology and severity of complications in IBS. Therefore, managing VH can remarkably modulate the symptoms of IBS. More preclinical and clinical investigations are needed to provide efficacious and targeted medicines for the management of VH.

Comparison of Electroacupuncture and Moxibustion for Relieving Visceral Hypersensitivity in Rats with Constipation-Predominant Irritable Bowel Syndrome

Aim. To compare whether there is different effect between electroacupuncture (EA) and moxibustion (Mox) on visceral hypersensitivity (their analgesic effects) in constipation-predominant irritable bowel syndrome (C-IBS). Methods. EA at 1 mA and 3 mA and Mox at 43°C and 46°C were applied to the Shangjuxu (ST37, bilateral) acupoint in rats with C-IBS and normal rats. An abdominal withdrawal reflex (AWR) score was used to assess visceral hypersensitivity. Toluidine blue staining was used to assess mast cell (MC) activity in colon of rats. Immunochemistry was used to measure 5-HT and 5-HT4 receptor expression in the colon. Results. AWR scores in all EA (1 mA and 3 mA) and Mox (43°C and 46°C) treatment groups after colorectal distention (CRD) stimulation pressure of 20, 40, 60, and 80 mmHg were significantly lower than those of the model (MC) group (P all < 0.01). The MC counts and degranulation rates in the colon of all EA and Mox treatment groups and the MC group were significantly higher than those of the NC group (P all < 0.01). MC degranulation rates in the colon of all EA and Mox treatment groups were lower than those of the MC group (P all < 0.05). 5-HT expression in colon of all EA and Mox treatment groups was significantly lower than that of the MC group (P all < 0.01), and 5-HT4R expression in colon of both EA groups was significantly higher than that of the MC group (P both < 0.01). Conclusion. EA and Mox treatments may both ameliorate visceral hypersensitivity at different degree in rats with C-IBS, and EA treatment was better than Mox.

Electroacupuncture for patients with diarrhea-predominant irritable bowel syndrome or functional diarrhea: A randomized controlled trial

Diarrhea-predominant irritable bowel syndrome (IBS-D) and functional diarrhea (FD) are highly prevalent, and the effectiveness of acupuncture for managing IBS-D and FD is still unknown.The aim of this study was to compare the effectiveness of electroacupuncture with loperamide.It was a prospective, randomized, parallel group controlled trial.A total of 448 participants were randomly assigned to He electroacupuncture group (n = 113), Shu-Mu electroacupuncture group (n = 111), He-Shu-Mu electroacupuncture group (n = 112), or loperamide group (n = 112). Participants in the 3 acupuncture groups received 16 sessions of electroacupuncture during a 4-week treatment phase, whereas participants in the loperamide group received oral loperamide 2 mg thrice daily. The primary outcome was the change from baseline in stool frequency at the end of the 4-weeks treatment. The secondary outcomes were the Bristol scale, the MOS 36-item short form health survey (SF-36), the weekly average number of days with normal defecations and the proportion of adverse events.Stool frequency was significantly reduced at the end of the 4-week treatment in the 4 groups (mean change from baseline, 5.35 times/week). No significant difference was found between the 3 electroacupuncture groups and the loperamide group in the primary outcome (He vs. loperamide group [mean difference 0.6, 95% CI, -1.2 to 2.4]; Shu-Mu vs. loperamide group [0.4, 95% CI, -1.4 to 2.3]; He-Shu-Mu vs. loperamide group [0.0, 95% CI, -1.8 to 1.8]). Both electroacupuncture and loperamide significantly improved the mean score of Bristol scale and increased the weekly average number of days with normal defecations and the mean scores of SF-36; they were equivalent in these outcomes. However, the participants in electroacupuncture groups did not report fewer adverse events than those in the loperamide group. Similar results were found in a subgroup analysis of separating patients with IBS-D and FD patients.Electroacupuncture is equivalent to loperamide for reducing stool frequency in IBS-D and FD patients. Further studies on cost effectiveness of acupuncture are warranted.

Electroacupuncture versus Moxibustion for Irritable Bowel Syndrome: A Randomized, Parallel-Controlled Trial

Objective. To compare the impacts of electroacupuncture (EA) and mild moxibustion (Mox) on patients with irritable bowel syndrome (IBS). Method. Eighty-two IBS patients were randomly allocated into EA group (n = 41) and Mox group (n = 41) and received corresponding interventions for four weeks. Before and after the treatment, the Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS) was used to evaluate the gastrointestinal symptoms and mental well-being; and the expression of serotonin (5-hydroxytryptamine, 5-HT), 5-HT₃ receptor (5-HT₃R), and 5-HT₄ receptor (5-HT₄R) in sigmoid mucosal tissue were detected. Results. Both EA and Mox can radically improve the total VAS-IBS score (P < 0.05), and EA was found to be more effective in ameliorating the symptom of constipation, while Mox was found to be more effective in ameliorating the symptom of diarrhoea. The abnormal expressions of 5-HT, 5-HT₃R, and 5-HT₄R in both groups were significantly improved after the treatments (all P < 0.05), and EA was superior to Mox in regulating the abnormally decreased 5-HT₄R expression in IBS patients with constipation (P < 0.05). Conclusion. Electroacupuncture and mild moxibustion were both effective in improving IBS symptoms and modulate abnormal expressions of 5-HT, 5-HT₃R, and 5-HT₄R in the colonic tissue.

Effects of electroacupuncture on corticotropin-releasing hormone in rats with chronic visceral hypersensitivity

AIM: To investigate the effect of electroacupuncture on corticotropin-releasing hormone (CRH) in the colon, spinal cord, and hypothalamus of rats with chronic visceral hypersensitivity.

METHODS: A rat model of chronic visceral hypersensitivity was generated according to the internationally accepted method of colorectal balloon dilatation. In the 7^th week after the procedure, rats were randomly divided into a model group (MG), electroacupuncture group (EA), and sham electroacupuncture group (S-EA). After treatment, the abdominal withdrawal reflex (AWR) score was used to assess the behavioral response of visceral hyperalgesia. Immunohistochemistry (EnVision method), ELISA, and fluorescence quantitative PCR methods were applied to detect the expression of CRH protein and mRNA in the colon, spinal cord, and hypothalamus.

RESULTS: The sensitivity of the rats to the colorectal distension stimulus applied at different strengths (20-80 mmHg) increased with increasing stimulus strength, resulting in increasing AWR scores in each group. Compared with NG, the AWR score of MG was significantly increased (P < 0.01). After conducting EA, the AWR scores of the rats were decreased compared with MG rats. The relative expression of CRH mRNA in the colon, spinal cord, and hypothalamus of MG rats was significantly increased compared with NG rats (P < 0.01). CRH mRNA in the colon and spinal cord of EA and S-EA rats was decreased to varying degrees (P > 0.05) compared with normal rats (NG). However, the decrease in EA compared with MG rats was statistically significant (P < 0.01). The average optical density of CRH expression in the colon of the MG rats was significantly enhanced compared with NG (P < 0.05), while the average optical density of CRH expression in the EA and S-EA rats was significantly decreased compared with MG rats (P < 0.01, P < 0.05, respectively). Compared with MG rats, the CRH concentration in the spinal cord of EA rats was significantly reduced (P < 0.01), but there was no significant change in S-EA rats (P > 0.05).

CONCLUSION: Electroacupuncture at the Shangjuxu acupoint was able to significantly reduce the visceral hypersensitivity in rats, and regulated the expression of CRH protein and mRNA in the colon, spinal cord and hypothalamus at different levels, playing a therapeutic role in this model of irritable bowel syndrome.

What is the Acupoint? A preliminary review of Acupoints

BACKGROUND

According to traditional Chinese medicine (TCM) theory, acupoints are specifically chosen sites of acupuncture manipulation, and also the basis for studying the mechanism of acupuncture. Stimulating different acupoints on the body surface could provide various therapeutic benefits. However, what is the acupoint? This question is not clear.

REVIEW SUMMARY

We focuse on examining the function of acupoints from different perspectives, including the local and the systemic effects of stimulating acupoints. For example, acupoints may release certain substances or incur some changes, which could adjust the function of organs, maintain homeostasis. Furthermore, the therapeutic effects of verum acupoints versus sham acupoints were discussed. However, due to insufficience in evidence and in current methodologies, research into mechanisms of acupuncture is still incomplete.

CONCLUSION

This review might explain, to some extent, what an acupoint is. Further research into the identity of acupoints is warranted, and multidisciplinary methods using novel technologies may yield significant advances over existing knowledge.

Effect of electroacupuncture on P2X3 receptor regulation in the peripheral and central nervous systems of rats with visceral pain caused by irritable bowel syndrome

The aim of this study is to investigate the role of the purinergic receptor P2X3 in the peripheral and central nervous systems during acupuncture treatment for the visceral pain of irritable bowel syndrome (IBS). A total of 24 8-day-old Sprague-Dawley (SD) neonatal male rats (SPF grade) were stimulated using colorectal distention (CRD) when the rats were awake. The modeling lasted for 2 weeks with one stimulation per day. After 6 weeks, the rats were randomly divided into three groups of eight each: (1) the normal group (NG, n = 8); (2) the model group (MG, n = 8); and (3) the model + electroacupuncture group (EA, n = 8) that received electroacupuncture at a needling depth of 5 mm at the Shangjuxu (ST37, bilateral) and Tianshu (ST25, bilateral) acupoints. The parameters of the Han's acupoint nerve stimulator (HANS) were as follows: sparse-dense wave with a frequency of 2/100 Hz, current of 2 mA, 20 min/stimulation, and one stimulation per day; the treatment was provided for seven consecutive days. At the sixth week after the treatment, the abdominal withdrawal reflex (AWR) score was determined; immunofluorescence and immunohistochemistry were used to measure the expression of the P2X3 receptor in myenteric plexus neurons, prefrontal cortex, and anterior cingulate cortex; and, a real-time PCR assay was performed to measure the expression of P2X3 messenger RNA (mRNA) in the dorsal root ganglion (DRG) and spinal cord. After stimulation with CRD, the expression levels of the P2X3 receptor in the inter-colonic myenteric plexus, DRG, spinal cord, prefrontal cortex, and anterior cingulate cortex were upregulated, and the sensitivity of the rats to IBS visceral pain was increased. Electroacupuncture (EA) could downregulate the expression of the P2X3 receptor and ease the sensitivity to visceral pain. The P2X3 receptor plays an important role in IBS visceral pain. The different levels of P2X3 in the peripheral enteric nervous system and central nervous system mediate the effects of the EA treatment of the visceral hyperalgesia of IBS.

Acupuncture for visceral pain: neural substrates and potential mechanisms

Visceral pain is the most common form of pain caused by varied diseases and a major reason for patients to seek medical consultation. Despite much advances, the pathophysiological mechanism is still poorly understood comparing with its somatic counterpart and, as a result, the therapeutic efficacy is usually unsatisfactory. Acupuncture has long been used for the management of numerous disorders in particular pain and visceral pain, characterized by the high therapeutic benefits and low adverse effects. Previous findings suggest that acupuncture depresses pain via activation of a number of neurotransmitters or modulators including opioid peptides, serotonin, norepinephrine, and adenosine centrally and peripherally. It endows us, by advancing the understanding of the role of ion channels and gut microbiota in pain process, with novel perspectives to probe the mechanisms underlying acupuncture analgesia. In this review, after describing the visceral innervation and the relevant afferent pathways, in particular the ion channels in visceral nociception, we propose three principal mechanisms responsible for acupuncture induced benefits on visceral pain. Finally, potential topics are highlighted regarding the future studies in this field.

An alternative to current therapies of functional dyspepsia: self-administrated transcutaneous electroacupuncture improves dyspeptic symptoms

Functional dyspepsia is of high prevalence with little treatment options. The aim of this study was to develop a new treatment method using self-management transcutaneous electroacupuncture (TEA) for functional dyspepsia (FD). Twenty-eight patients with FD were enrolled and underwent a crossover clinical trial with 2-week TEA at ST36 and PC6 and 2-week sham-TEA at nonacupuncture sham-points. Questionnaires were used to assess symptoms of dyspepsia and quality of life. Physiological testing included gastric emptying and electrogastrography. It was found that (1) TEA but not sham-TEA significantly improved dyspeptic symptoms and 4 domains in quality of life; improvement was also noted in self-rated anxiety and depression scores; (2) gastric emptying was significantly and substantially increased with 2-week TEA but not sham-TEA; and (3) gastric accommodation was also improved with TEA but not sham-TEA, reflected as increased ingested nutrient volumes at the levels of satiety and maximum tolerance. These findings suggest a therapeutic potential of self-administrated TEA method for functional dyspepsia, possibly attributed to improvement in gastric motility.