Ameliorating effects and autonomic mechanisms of needle-less transcutaneous electrical stimulation at ST36 on stress-induced impairment in gastric slow waves

Electroacupuncture pretreatment at ST36 alleviates acute gastric mucosal lesions induced by water immersion restraint stress through the TRPV1/SP/CGRP/NO pathway in rats

OBJECTIVE

The aim of this study was to determine the impact of electro-acupuncture (EA) pretreatment on the progression of acute gastric mucosal lesions (AGMLs) induced by water immersion restraint stress (WIRS) and explore the related mechanisms including the transient receptor potential vanilloid (TRPV)1 signaling pathways.

METHODS

Rats treated with EA for 4 days were subjected to WIRS for 6 h. Microscopic lesions, oxidative stress and TRPV1, substance P (SP), calcitonin gene-related peptide (CGRP) and nitric oxide (NO) levels in the dorsal root ganglion (DRG) and gastric tissues were detected.

RESULTS

The results indicated the development of AGMLs with a substantial increase of TRPV1/SP in the DRG and TRPV1/SP/MDA (malondialdehyde activity) in the stomach, and a significant decrease in CGRP/NO/SOD (superoxide dismutase) in gastric tissues, using a combination of real-time reverse transcription polymerase chain reaction, Western blotting and enzyme-linked immunosorbent assay.

CONCLUSION

The TRPV1 signaling pathways likely play an important role in the pathogenesis of AGML. In addition, EA pretreatment protected gastric mucosa lesions induced by WIRS by reducing the expression of TRPV1/SP in the DRG and gastric mucosa, as well as up-regulating gastric CGRP/NO. Antioxidant mechanisms are likely to at least partially mediate the protective effects of EA against AGML.

Autonomic and cytokine mechanisms of acute electroacupuncture in a rodent model of functional dyspepsia

BACKGROUND

Cytokines have been presumed to play an important role in the pathophysiology of functional dyspepsia (FD). Electroacupuncture (EA) has been used for FD treatment; however, its mechanisms remain largely unknown. This study aimed to (1) compare the plasma levels of cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-10, in "FD" rats with normal control rats; (2) investigate whether EA, using chronically implanted electrodes, could inhibit the release of these cytokines; and (3) explore the correlation of cytokine levels with plasma norepinephrine (NE) levels and gastric emptying (GE).

METHODS

A rodent model of FD was established via neonatal treatment with intragastric iodoacetamide. After 8 weeks, the rats were implanted with electrodes at acupoint ST36 for EA. The plasma levels of cytokines and NE were measured using enzyme-linked immunosorbent assay. We explored the correlations of cytokine levels with NE levels and GE.

KEY RESULTS

(i) "FD" rats demonstrated increased levels of TNF-α, IL-1β, and IL-6 (p < 0.05 each) compared with the control rats. (ii) EA significantly decreased the plasma levels of TNF-α, IL-1β, and IL-6 in "FD" rats (p < 0.05 each) compared with sham EA. (iii) The plasma levels of NE were positively correlated with those of IL-6 (r = 0.86, p < 0.05) and IL-1β (r = 0.81, p < 0.05), whereas NE levels and GE were negatively correlated with IL-10 levels (r = -0.870, p < 0.05 and r = -0.791, p < 0.05, respectively).

CONCLUSIONS

EA inhibits the release of proinflammatory cytokines probably via the suppression of sympathetic activity in "FD" rats.

Effect and mechanism of needleless transcutaneous neuromodulation on gastrointestinal function after pancreaticoduodenectomy

BACKGROUND

Gastrointestinal motility disorders tend to develop after pancreaticoduodenectomy (PD). The objectives of this study were: (1) to investigate the impact of needleless transcutaneous neuromodulation (TN) on the postoperative recuperation following pancreaticoduodenectomy (PD), and (2) to explore the underlying mechanisms by which TN facilitates the recovery of gastrointestinal function after PD.

METHODS

A total of 41 patients scheduled for PD were randomized into two groups: the TN group (n = 21) and the Sham-TN group (n = 20). TN was performed at acupoints ST-36 and PC-6 twice daily for 1 h from the postoperative day 1 (POD1) to day 7. Sham-TN was performed at non-acupoints. Subsequent assessments incorporated both heart rate variation and dynamic electrogastrography to quantify alterations in vagal activity (HF) and gastric pacing activity.

RESULTS

1)TN significantly decreased the duration of the first passage of flatus (p < 0.001) and defecation (p < 0.01) as well as the time required to resume diet (p < 0.001) when compared to sham-TN;2)Compared with sham-TN, TN increased the proportion of regular gastric pacing activity (p < 0.01);3) From POD1 to POD7, there was a discernible augmentation in HF induced by TN stimulation(p < 0.01);4) TN significantly decreased serum IL-6 levels from POD1 to POD7 (p < 0.001);5) TN was an independent predictor of shortened hospital stay(β = - 0.349, p = 0.035).

CONCLUSION

Needleless TN accelerates the recovery of gastrointestinal function and reduces the risk of delayed gastric emptying in patients after PD by enhancing vagal activity and controlling the inflammatory response.

Noninvasive Transcutaneous Auricular Vagal Nerve Stimulation Improves Gastric Slow Waves Impaired by Cold Stress in Healthy Subjects

BACKGROUND/AIMS

Stress is known to inhibit gastric motility. The aim of this study was to investigate the effects and autonomic mechanisms of transcutaneous auricular vagal nerve stimulation (taVNS) on cold stress (CS)-induced impairment in gastric motility that are relevant to the brain-gut interactions in healthy volunteers.

MATERIALS AND METHODS

Healthy volunteers (eight women; age 28.2 ± 1.8 years) were studied in four randomized sessions (control, CS, CS + taVNS, and CS + sham-electrical stimulation [sham-ES]). Each session was composed of 30 minutes in the fasting state and 30 minutes after a standard test meal. CS was induced during minutes 10 to 30 after the meal, whereas taVNS or sham-ES was performed during minutes 0 to 30 after the meal. The electrogastrogram and electrocardiogram were recorded for assessing gastric slow waves and autonomic functions, respectively.

RESULTS

First, CS decreased the percentage of normal gastric slow waves (59.7% ± 9.8% vs 85.4% ± 4.5%, p < 0.001 vs control); this impairment was dramatically improved by taVNS (75.5% ± 6.3% vs 58.4% ± 12.5%, p < 0.001 vs sham-ES). Second, CS increased the symptom score (22.0 ± 12.1 vs 39.3 ± 11.5, p = 0.001 vs control); taVNS, but not sham-ES, reduced the symptom score (26.0 ± 12.2 vs 38.3 ± 21.6, p = 0.026 vs sham-ES). Third, CS decreased vagal activity assessed from the spectral analysis of heart rate variability (0.21 ± 0.10 vs 0.26 ± 0.11, p < 0.05 vs control) and increased the sympathovagal ratio (4.89 ± 1.94 vs 3.74 ± 1.32, p = 0.048 vs control); taVNS normalized CS-induced suppression in vagal activity (0.27 ± 0.13 vs 0.22 ± 0.10, p = 0.049 vs sham-ES; p > 0.05 vs control) and CS-induced increase in the sympathovagal ratio (3.28 ± 1.61 vs 4.28 ± 2.10, p = 0.042 vs sham-ES; p > 0.05 vs control).

CONCLUSION

The noninvasive taVNS improves the CS-induced impairment in gastric pace-making activity, possibly by reversing the detrimental effect of CS on autonomic functions. taVNS may have a therapeutic potential for stress-induced gastric dysmotility.

Non-invasive neuromodulation: an emerging intervention for visceral pain in gastrointestinal disorders

Gastrointestinal (GI) disorders, which extend from the esophagus to the anus, are the most common diseases of the GI tract. Among these disorders, pain, encompassing both abdominal and visceral pain, is a predominant feature, affecting the patients' quality of life and imposing a substantial financial burden on society. Pain signals originating from the gut intricately shape brain dynamics. In response, the brain sends appropriate descending signals to respond to pain through neuronal inhibition. However, due to the heterogeneous nature of the disease and its limited pathophysiological understanding, treatment options are minimal and often controversial. Consequently, many patients with GI disorders use complementary and alternative therapies such as neuromodulation to treat visceral pain. Neuromodulation intervenes in the central, peripheral, or autonomic nervous system by alternating or modulating nerve activity using electrical, electromagnetic, chemical, or optogenetic methodologies. Here, we review a few emerging noninvasive neuromodulation approaches with promising potential for alleviating pain associated with functional dyspepsia, gastroparesis, irritable bowel syndrome, inflammatory bowel disease, and non-cardiac chest pain. Moreover, we address critical aspects, including the efficacy, safety, and feasibility of these noninvasive neuromodulation methods, elucidate their mechanisms of action, and outline future research directions. In conclusion, the emerging field of noninvasive neuromodulation appears as a viable alternative therapeutic avenue for effectively managing visceral pain in GI disorders.

Clinical Efficacy and Mechanism of Transcutaneous Neuromodulation on Functional Dyspepsia

BACKGROUND AND AIMS

Prokinetics and proton pump inhibitors are first-line drugs for functional dyspepsia (FD) patients. However, no available treatment is effective for most FD patients, and the pathogenesis is still unclear. The purpose of this study was to investigate the therapeutic effect of transcutaneous neuromodulation (TN) on FD and its potential mechanisms.

MATERIALS AND METHODS

Fifty-seven FD patients were enrolled in the study and randomly divided into 3 groups (TN Neiguan (PC6) group, TN Zusanli (ST36) group, and sham TN group) that received corresponding treatment respectively for 4 weeks. Then, all the patients enrolled received TN PC6 combined with ST36 treatment for another 4 weeks. Dyspepsia symptom questionnaire, Medical outcomes study item short form health survey (SF-36), Hospital Anxiety and Depression Scale were used to assess the severity of symptoms. Gastric accommodation, gastric emptying rate, and related parameters of electrogastrogram were used to assess the pathophysiological mechanism of FD. The possible gastrointestinal hormonal mechanism involved was assessed by detecting serum ghrelin, neuropeptide Y, and vasoactive intestinal peptide. The possible duodenal inflammation mechanism involved was assessed by detecting duodenal mucosa.

RESULTS

TN treatment reduced the dyspepsia symptom score ( P <0.05) and improved the quality of life. After TN treatment, the gastric accommodation ( P <0.01), the gastric emptying rate ( P <0.01), and the percentages of preprandial ( P <0.05) and postprandial ( P <0.05) gastric slow waves (GSW) were increased. The proportions of preprandial ( P <0.05) and postprandial ( P <0.05) gastric electrical rhythm disorder were reduced. The double acupoint combination therapy further enhanced the therapeutic effect of single acupoint. In addition, the levels of ghrelin ( P <0.001) and neuropeptide Y ( P <0.001) were significantly increased, the level of vasoactive intestinal peptide ( P <0.001) was significantly decreased, and the total number of mast cells ( P <0.001) in the duodenal bulb was significantly decreased after double acupoints combination therapy.

CONCLUSIONS

TN treatment significantly improves the dyspepsia symptoms of FD patients and their quality of life. TN treatment increases the percentage of normal GSW, reduces the proportion of gastric electrical rhythm disorder, and improves the gastric accommodation and gastric emptying rate. The therapeutic effect of TN may be caused by regulating gastrointestinal hormone secretion and alleviating local inflammatory responses in duodenum. In addition, the improvement of TN on GSW was closely related to the decrease of bradygastria.

Home‐based transcutaneous electrical acupoint stimulation for high‐normal blood pressure: A randomized controlled trial

The authors investigated the effectiveness of home‐based transcutaneous electrical acupoint stimulation (TEAS) combined with lifestyle modification on blood pressure (BP) control and explored the feasibility of the trial design in this prospective, randomized controlled trial. The authors recruited individuals with high‐normal BP who had a systolic blood pressure (SBP) of 120–139 mm Hg and a diastolic blood pressure (DBP) of 80–89 mm Hg, or both. Participants were randomly assigned to receive either lifestyle modification combined with TEAS four times weekly for 12 weeks at home (intervention group) or solely lifestyle modification (control group). The primary outcome was the change in mean SBP at week 12 from the baseline measurement. A total of 60 participants were randomized in a 1:1 ratio, and an intention‐to‐treat analysis was performed on all of the outcomes. The mean difference in the change in SBP for the intervention group (compared to the control) at week 12 was −3.85 mm Hg (95% CI: −7.58 to −.12; p = .043); for the DBP, the change was −2.27 mm Hg (95% CI: −5.76 to 1.23; p = .199). There was no difference in the proportion of progression to hypertension, quality of life, body mass index (BMI) or waist circumference. In addition, two participants reported TEAS‐related adverse events. The authors found a reduction in SBP control in the pragmatic, home‐based intervention by using TEAS combined with lifestyle modification in adults with high‐normal BP.

Trial Registration: The study was registered in the Chinese Clinical Trial Registry (ChiCTR 1900024982) on August 6, 2019.

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.

Auricular vagal nerve stimulation enhances gastrointestinal motility and improves interstitial cells of Cajal in rats treated with loperamide

BACKGROUND

Gastrointestinal (GI) motility disorders affect a large proportion of the population with limited treatment options. The aims of this study were to investigate the potential of a non-invasive method of auricular vagal nerve stimulation (aVNS) for treating GI dysmotility and to explore possible mechanisms involving slow waves and interstitial cells of Cajal (ICC).

METHODS

Normal rats were treated daily with loperamide for 1 week and then treated, while still on daily loperamide, with aVNS/Sham-aVNS for another 1 week. Gastric emptying (GE), small intestine transit (SIT), and GI slow waves were measured. The plasma level of pancreatic polypeptide (PP) and noradrenaline (NE) was assessed by ELISA. ICC in the gastric antrum were detected by immunohistochemistry.

KEY RESULTS

(a) aVNS significantly increased the percentage of normal GI slow waves (p < 0.05 for both fasting and postprandial states, vs. Sham-aVNS) and accelerated GE (p < 0.05, vs. Sham-aVNS) and SIT (p < 0.05, vs. Sham-aVNS) impaired by loperamide. (b) aVNS increased plasma PP (p < 0.01) and decreased plasma NE (p < 0.01), compared with Sham-aVNS. (c) Gastric ICC was decreased by loperamide (p < 0.01) but increased after aVNS (p < 0.01, vs. Sham aVNS).

CONCLUSIONS & INFERENCES

Loperamide induces upper GI dysmotility. aVNS accelerates upper GI transit and improving pace-making activity mediated via the ICC. Non-invasive aVNS may have a therapeutic potential for upper GI dysmotility.

Integrative Effects and Vagal Mechanisms of Transcutaneous Electrical Acustimulation on Gastroesophageal Motility in Patients With Gastroesophageal Reflux Disease

INTRODUCTION

Impaired esophageal and gastric motilities are known to contribute to symptoms of gastroesophageal reflux disease (GERD). However, there is a lack of GERD therapy, targeting both gastric and esophageal functions. This study was designed to investigate the effects of transcutaneous electrical acustimulation (TEA) on symptoms of GERD and gastroesophageal functions and possible mechanisms in patients with GERD.

METHODS

Thirty patients with GERD with ineffective esophageal motility were equally divided and randomized into a 4-week sham-TEA or 4-week TEA treatment. The GERD questionnaire (GerdQ), GERD health-related quality-of-life questionnaire, high-resolution esophageal manometry, a nutrient drink test, the electrogastrogram, and ECG were performed to assess the severity of reflux symptoms, low esophageal sphincter (LES) pressure, distal contractile integral (DCI), gastric accommodation, gastric slow waves (GSW), and autonomic functions, respectively.

RESULTS

Compared with sham-TEA, the 4-week TEA treatment significantly decreased the GerdQ score (P = 0.011) and GERD health-related quality of life (P = 0.028) and improved nutrient drink-induced fullness (P < 0.001) and belching (P < 0.001) in patients with GERD. Although only acute TEA significantly enhanced LES pressure (P < 0.05), both acute and chronic TEA remarkedly increased DCI (P < 0.05) and reduced the incidence of ineffective esophageal contractions during wet swallows (P = 0.02). In addition, chronic TEA significantly increased gastric accommodation and the percentage of postprandial normal GSW compared with sham-TEA and baseline. Concurrently, TEA-enhanced vagal activity (P = 0.02) and the vagal activity positively correlated with LES pressure (r = 0.528; P = 0.003) and DCI (r = 0.522; P = 0.003).

DISCUSSION

The TEA treatment performed in this study improves reflux-related symptoms, increases DCI, reduces the incidence of ineffective esophageal contractions during wet swallows, and improves gastric accommodation and slow waves. The improvement in GERD symptoms might be attributed to the integrative effects of TEA on these gastroesophageal functions mediated via the vagal mechanism.

Transcutaneous Acupoint Electrical Stimulation on Chemotherapy-Induced Constipation for Non-Small Cell Lung Cancer Patients: A Randomized Controlled Trial

Objective:

Chemotherapy-induced constipation (CIC) adversely affects the quality of life of non-small cell lung cancer (NSCLC) patients. This study aimed to investigate the clinical effects of transcutaneous acupoint electrical stimulation (TAES) on CIC.

Methods:

Sixty NSCLC patients who received chemotherapy at Hunan Cancer Hospital, Changsha, China, were assigned to the TAES (n = 30) or control (n = 30) group using Research Randomizer. In the TAES group, four acupoints, namely Tianshu, Quchi, Zusanli, and Shangjuxu, were stimulated six times a week, lasting for 4 weeks, while the control group received the usual care. The Bristol Stool Form Scale (BSFS) and the Constipation Assessment Scale (CAS) were used.

Results:

Both the BSFS and CAS scores for the experimental group were significantly higher than that for the control group (P = 0.004 and P < 0.001 separately).

Conclusions:

TAES was effective for alleviating constipation in NSCLC patients receiving chemotherapy and was a safe and practical nursing intervention.

Acupuncture at Back-Shu and Front-Mu Acupoints Prevents Gastric Ulcer by Regulating the TLR4/MyD88/NF-κB Signaling Pathway

Purpose

To assess the preventive effects of acupuncture at back-shu and front-mu acupoints on rats with restraint water-immersion stress (RWIS)-induced gastric ulcer.

Methods

Thirty-six rats were randomly divided into four groups for 10 days of treatment as follows: the normal group received no treatment; the model group received RWIS-induced gastric ulcer; the omeprazole group was administered omeprazole orally every 2 days; and the electroacupuncture group received electroacupuncture at the RN12 and BL21 acupoints every 2 days. After 10 days of treatment, except for the normal group, all rats were induced with gastric ulcer by RWIS for 3 h. The ulcer index (UI), ulcer inhibition rate, and histopathological score were calculated. We determined the levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in serum, and the activities of myeloperoxidase (MPO), malondialdehyde (MDA), superoxide dismutase (SOD), nitric oxide (NO), and glutathione peroxidase (GSH-Px) in serum and gastric tissues. Protein expression of MyD88, nuclear factor (NF)-κB (p65), and toll-like receptor (TLR) 4 was quantified in gastric tissues.

Results

The electroacupuncture and omeprazole groups were equivalent in terms of UI, ulcer inhibition rate, and histopathological score. The serum levels of TNF-α and IL-6 were significantly lower in the electroacupuncture group compared with the omeprazole group (P < 0.05). Compared with the model group, there were significant changes in the levels of NO, MPO, GSH-Px, and MDA in all other groups, while the expression of TLR4, MyD88, and NF-κB p65 in gastric tissue decreased significantly in the electroacupuncture group. The expression of TLR4 was substantially lower in the electroacupuncture group compared with the omeprazole group.

Conclusion

Acupuncture at back-shu and front-mu acupoints played a role in preventing gastric ulcer by inhibiting extracellular signals, stimulating kinases in serum and gastric tissues, and activating the inhibition of the TLR4 signaling pathway.

Ameliorating Effects of Transcutaneous Electrical Acustimulation at Neiguan (PC6) and Zusanli (ST36) Acupoints Combined with Adaptive Biofeedback Training on Functional Outlet Obstruction Constipation

BACKGROUND

Stimulant laxatives are still considered the most common treatment for functional outlet obstruction constipation (FOOC). However, the effectiveness of laxatives is unsatisfactory, and the long-term use of laxatives may cause certain adverse events. With this in mind, it is, however, paramount that novel complementary treatment(s) and/or other forms of alternative medicine are adequately investigated.

AIMS

The study aims to explore the effects and potential mechanism(s) of transcutaneous electrical acustimulation (TEA) combined with adaptive biofeedback training (ABT) on FOOC.

METHODS

A total of forty-five patients with FOOC were recruited and were randomly assigned to receive either Macrogol 4000 Powder (MAC, 10 g bid) (group A, n = 15) only, ABT + MAC + Sham-TEA (group B, n = 15), or TEA + ABT + MAC (group C, n = 15) in a six-week study. Individual patients' constipation-symptoms (PAC-SYM) and constipation-quality of life (PAC-QOL) were both assessed and scored. Serum acetylcholine (Ach) and nitric oxide (NO) were measured from drawn blood samples while individual patients' heart rate variability (HRV) was calculated at baseline and after each corresponding therapy. Anorectal manometry and balloon expulsion test were both performed before and after treatment.

RESULTS

Firstly, participants in group C had significantly lower scores of PAC-SYM, PAC-QOL, and a decreased anal defecating pressure (ADP) as compared to participants in group B (all p < 0.050). These results, however, suggest the TEAs effect. Secondly, the low-frequency band (LF)/(LF + HF) ratio in groups B and C were decreased as compared to group A (p=0.037, p=0.010, respectively) regarding HRV. On the other hand, the high-frequency band (HF)/(LF + HF) ratio in groups B and C showed an opposite outcome. Finally, the serum Ach in groups B and C was significantly higher as compared to group A (p=0.023, p=0.012, respectively). Of significant importance, the serum NO in groups B and C were notably low as compared to group A (p=0.001, p < 0.001, respectively).

CONCLUSIONS

TEA, combined with ABT, effectively improves constipation symptoms as well as QOL in FOOC patients. It is, however, achieved by decreasing ADP, which mechanisms are mediated via the autonomic and enteric mechanisms.

Effects of electroacupuncture on stress-induced gastric dysrhythmia and mechanisms involving autonomic and central nervous systems in functional dyspepsia

Electroacupuncture (EA) is widely used as an effective method to treat stress-related disorders. However, its mechanisms remain largely unknown. The aim of this study was to investigate the effects and mechanisms of EA on gastric slow wave (GSW) dysrhythmia and c-Fos expression in the nucleus of the solitary tract (NTS) induced by stress in a rodent model of functional dyspepsia (FD). Rats in the neonatal stage were treated using intragastric iodoacetamide. Eight weeks later, the rats were implanted with electrodes in the stomach for the measurement of GSW and electrodes into accupoints ST36 for EA. Autonomic functions were assessed by spectral analysis of heart rate variability. Rats were placed for 30 min in a cylindrical plastic tube for acute restraint stress. The involvement of a central afferent pathway was assessed by measuring c-Fos-immunoreactive cells in the NTS. 1) EA normalized restraint stress-induced impairment of GSW in FD rats. 2) EA significantly increased vagal activity (P = 0.002) and improved sympathovagal balance (P = 0.004) under stress in FD rats. 3) In FD rats under restraint stress, plasma norepinephrine concentration was increased substantially (P < 0.01), which was suppressed with EA. 4) The EA group showed increased c-Fos-positive cell counts in the NTS compared with the sham EA group (P < 0.05) in FD rats. Acute restraint stress induces gastric dysrhythmia in a rodent model of FD. EA at ST36 improves GSW under stress in FD rats mediated via the central and autonomic pathways, involving the NTS and vagal efferent pathway.

Transcutaneous Electrical Acustimulation Improves Gastrointestinal Disturbances Induced by Transcatheter Arterial Chemoembolization in Patients With Liver Cancers

BACKGROUND

Gastrointestinal (GI) disturbances occur in patients who receive chemotherapy via transcatheter arterial chemoembolization (TACE) and could last for an extended period of time in some cases. Antiemetic drugs have a potential risk of developing hepatic failure and are ineffective for delayed nausea and emesis. Transcutaneous electrical acustimulation (TEA) has recently been reported to exert antiemetic and prokinetic effects, but it is unknown whether it has an ameliorating effect on TACE-induced GI disturbances.

AIM

This study was designed to evaluate effects and mechanisms of noninvasive TEA on GI symptoms in patients treated with TACE.

MATERIALS AND METHODS

Seventy-four patients with liver cancers (eighteen female; age 63.4 ± 1.1 years) scheduled for TACE were randomized to TEA (n = 37) or sham-TEA (n = 37). TEA was performed via acupoints, ST36 and PC6 using parameters previously optimized for GI motility (1 h, bid) from the postoperative day 0 (POD0) to POD2. Sham-TEA was performed using the same parameters via non-acupoints. Symptom questionnaires were completed daily. The electrogastrogram (EGG) and electrocardiogram (ECG) were recorded in the fasting state for 30 mins to assess gastric slow waves and autonomic functions, respectively, before and after the 3-day treatment.

RESULTS

1) In the acute phase (<24 h), TEA showed no effects on any of GI symptoms, compared with sham-TEA. 2) In the delayed phase (>24 h), TEA, compared with sham-TEA, decreased the percentage of patients who experienced nausea on POD3 (0% vs. 13.5%, p = 0.021), the nausea score on POD3 (p = 0.022), the anorexia score on POD2 (p = 0.040) and POD3 (p = 0.004), and the bloating score (POD1-3: p < 0.01). 3) In comparison with sham-TEA, TEA increased the number of spontaneous bowel movements (p = 0.001) and the Bristol score of the first stool (p = 0.014) and decreased the number of patients with the use of laxatives (p = 0.022). 4) Physiologically, the 3-day TEA but not sham-TEA increased the percentage of normal gastric slow waves (p < 0.001) and vagal activity (p = 0.006). The vagal activity was negatively correlated with the anorexia score (r = -0.267, p = 0.026). It was found that the sympathovagal ratio and tumor size>5 cm were independent risk factors predicting the occurrence of nausea in patients after TACE.

CONCLUSION

TEA improves major TACE-induced GI disturbances in the delayed phase, including nausea, bloating, impaired gastric pace-making activity, and constipation in patients with liver cancers via the autonomic pathway.

Effects of Varying Acupuncture Manipulations at ST36 (Zusanli) on Gastric Electrical Frequency and Amplitude in Bradygastria Rabbits

Objective

To observe the effects of different manual acupuncture (MA) manipulation on gastric electrical amplitude and frequency for noradrenaline-induced bradygastria in rabbits.

Methods

A total of 60 rabbits were randomly allocated into six groups: four MA manipulation groups; reinforcing by twisting the manipulation group (FTG), reducing by twisting the manipulation group (RTG), reinforcing by lifting and thrusting the manipulation group (FLG), and reducing by lifting and thrusting the manipulation group (RLG), a control group (CG), and a model group (MG). The total treatment time length was 45 minutes. The bradygastria was induced via administration of noradrenaline via the marginal ear vein of the rabbits at 5 minutes from baseline, and the bradygastria model was established at 12 minutes from baseline. The rabbits in the four MA manipulation groups received different stimulation parameters at ST36 (Zusanli) for a duration of 3 minutes in accordance with their respective group allocation. The needles were then retained without further manipulation for a further 25 minutes. Gastric electrical amplitude and frequency were recorded using a data acquisition system (Biopac System MP150) at five different time points: baseline (for a duration of 5 minutes), after the bradygastria model was established at 12 minutes from baseline (for a duration of 5 minutes), during MA manipulation commencing at 17 minutes from baseline (for a duration of 3 minutes), 5 minutes after MA manipulation at 25 minutes from baseline (for a duration of 5 minutes), and at 20 minutes following MA manipulation at 40 minutes from baseline (for a duration of 5 minutes).

Results

After noradrenaline induction, gastric electrical frequency levels in MA and MG groups were significantly decreased compared to the CG group (P < 0.05). However, there were no significant changes to gastric electrical amplitude (P < 0.05). However, there were no significant changes to gastric electrical amplitude (P < 0.05). However, there were no significant changes to gastric electrical amplitude (P < 0.05). However, there were no significant changes to gastric electrical amplitude (P < 0.05). However, there were no significant changes to gastric electrical amplitude (P < 0.05). However, there were no significant changes to gastric electrical amplitude (

Conclusion

All four variations of MA manipulations have a recovery effect on the gastric electrical frequency of rabbits with bradygastria. In particular, results indicated that FTG, RTG, and FLG at ST36 may have a regular and significant recovery trend through the whole process of the acupuncture intervention.

Poststroke Constipation Is Associated With Impaired Rectal Sensation

OBJECTIVES

Constipation is prevalent in individuals after stroke. However, the pathophysiological mechanisms of poststroke constipation remain unclear. This study was designed (i) to investigate the difference in anorectal motility and rectal sensation among stroke patients with constipation, stroke patients without constipation, and healthy controls (HC), (ii) to evaluate the impact of stroke sites on constipation and rectal sensation, (iii) to explore the role of autonomic functions, and (iv) to determine the independent risk factors for poststroke constipation.

METHODS

Seventy-one stroke patients and 24 HC were recruited. General information, clinical characteristics, and relevant questionnaires were collected. Meanwhile, an anorectal manometry test was performed to assess functions of anorectal motility and rectal sensation, and an electrocardiogram was recorded to evaluate autonomic functions.

RESULTS

(i) Constipation patients exhibited increased rectal sensation thresholds, compared with patients without constipation or HC (P < 0.001). Almost no difference was detected in anorectal motility parameters among 3 groups. Constipation-associated clinical characteristics, such as spontaneous bowel movements, were weakly or moderately correlated with rectal sensation thresholds (P < 0.05 to P < 0.001 for various parameters). (ii) Patients with brainstem lesions had increased prevalence of constipation and first sensation threshold, compared with patients without brainstem lesions (P = 0.045, P = 0.025, respectively). (iii) There was a weak positive correlation between sympathetic activity and stroke severity and a weak negative one between vagal activity and stroke severity. Rectal sensation thresholds were positively and weakly correlated with sympathetic activity but negatively with vagal activity. (iv) The desire of defecation threshold and the physical activity were independent risk factors for poststroke constipation (P = 0.043, P = 0.025, respectively).

DISCUSSION

Poststroke constipation is characterized by elevated thresholds for rectal sensation, rather than altered anorectal motility. Patients with brainstem lesions are predisposed to constipation possibly because of the disruption of afferent pathway from the rectum to the brain. Moreover, the desire of defecation threshold and the physical activity level are factors independently associated with poststroke constipation.

Ameliorating Effects and Autonomic Mechanisms of Transcutaneous Electrical Acustimulation in Patients With Gastroesophageal Reflux Disease

BACKGROUND/AIM

Gastric dysmotility is one of pathophysiologies of gastroesophageal reflux disease (GERD). The aim of this study was to investigate the effects of transcutaneous electrical acustimulation (TEA) on gastric accommodation and gastric slow waves, and evaluate possible mechanisms in patients with GERD.

METHODS

Thirty patients were studied in two randomized sessions of sham-TEA and TEA with the measurements of esophageal high-resolution manometry (HRM), gastric accommodation assessed by a nutrient-drinking test, electrogastrogram (EGG), electrocardiogram (ECG), and postprandial dyspeptic symptoms.

RESULTS

Compared with sham-TEA, TEA improved nutrient drinking-induced fullness (42.0 ± 3.3 vs. 31.0 ± 3.5, P = 0.003) at 10 min after the drink, and belching right after the drink (22.0 ± 4.6 vs. 11.7 ± 3.1, P = 0.012) and at 10 min (16.0 ± 3.8 vs. 3.0 ± 1.5, P = 0.002) after the drink. TEA also improved gastric accommodation (954 ± 37 mL vs. 857 ± 47 mL, P = 0.001) and normalized maximal drink-induced impairment in gastric slow waves. Concurrently, TEA enhanced vagal activity assessed from spectral analysis of heart rate variability in the postprandial state (0.42 ± 0.03 vs. 0.49 ± 0.04, P = 0.039). The vagal activity was positively correlated with the percentage of normal slow waves (r = 0.528; P = 0.003) and negatively correlated with the regurgitation score (r = -0.408, P = 0.025).

CONCLUSIONS

Acute TEA increases gastric accommodation, improves gastric slow waves, and reduces postprandial fullness and belching, possibly mediated via the vagal mechanisms.

Ameliorating Effects of Transcutaneous Electrical Acustimulation Combined With Deep Breathing Training on Refractory Gastroesophageal Reflux Disease Mediated via the Autonomic Pathway

AIMS

To investigate the effects and possible mechanisms of transcutaneous electrical acustimulation (TEA) combined with deep breathing training (DBT) on refractory gastroesophageal reflux disease (rGERD).

METHODS

Twenty-one patients with rGERD were recruited and randomly assigned to receive either only esomeprazole (ESO, 20 mg bid) (group A, n = 7), TEA + DBT + ESO (group B, n = 7), or sham-TEA + DBT + ESO (group C, n = 7) in a four-week study. The reflux diagnostic questionnaire (RDQ) score and heart rate variability (HRV) were recorded and evaluated at baseline and at the end of each treatment. Blood samples were collected for the measurement of serum acetylcholine (Ach) and nitric oxide (NO). Esophageal manometry and 24-hour pH monitoring were performed before and after the treatment.

RESULTS

After treatment, 1) the participants in group B had significantly lower scores of RDQ and DeMeester and increased lower esophageal sphincter pressure (LESP) than those in group C (all p < 0.05), suggesting the role of TEA; 2) low frequency band (LF)/(LF + HF) ratio in groups B and C was decreased, compared with group A (p = 0.010, p = 0.042, respectively); high frequency band (HF)/(LF + HF) ratio in B and C groups was significantly increased, compared with group A (p = 0.010, p = 0.042, respectively); 3) The serum Ach in groups B and C was significantly higher than group A (p = 0.022, p = 0.046, respectively); the serum NO in groups B and C was significantly lower than group A (p = 0.010, p = 0.027, respectively).

CONCLUSIONS

TEA combined with the DBT can effectively improve the reflux symptoms in rGERD patients by increasing LESP and reducing gastroesophageal reflux, which may be mediated via the autonomic and enteric mechanisms.

Repeated transcutaneous electrical nerve stimulation of nonspecific acupoints of the upper body attenuates stress-induced visceral hypersensitivity in rats

Irritable bowel syndrome (IBS) is a common stress-related gastrointestinal disorder and visceral hypersensitivity (VH) is characteristically found in IBS patients. Transcutaneous electrical nerve stimulation (TENS) applied to certain acupoints has been shown to benefit IBS patients. Here, we investigated whether nonspecific acupoint is involved in the efficacy of TENS treatment for IBS. Twenty-five male rats were randomly assigned to four experimental groups and one sham-control group. The four experimental groups were defined as TENS-RR, TENS-RL, TENS-LR, and TENS-LL based on the location of the two TENS patches [right (R) or left (L)]. The former and latter letter pairs indicate that the patch locations were the upper chest and upper back, respectively. The heterotypic intermittent stress (HIS) protocol was performed for 16 days. VH was assessed by electromyography to evaluate response to rectal distention (RD). Modulated medium-frequency TENS, sweep range 1-10 Hz, amplitude slightly above the supra motor threshold, was applied 30 min per day followed by RD every second day for the final 7 days of the 16-day HIS period. VH was induced after the rats had been subjected to HIS for 10 days. A significant reduction of VH was observed only in the TENS-LL group compared with that in the sham-control group. These data suggest that repeated TENS treatment can alleviate stress-induced VH in rats. Further, whether TENS patches are attached to the left or right side of the body, which are nonspecific acupoints for gastrointestinal functions, may be an important factor in the treatment of stress-associated gastrointestinal symptoms.

Prokinetic effects of spinal cord stimulation and its autonomic mechanisms in dogs

BACKGROUND

Spinal cord stimulation (SCS) is widely used to treat chronic pain by inhibiting sympathetic activity; however, it is unknown whether it exerts a prokinetic effect on gastric motility. Our aim was to explore effects and possible mechanisms of SCS on glucagon-induced gastric dysmotility and dysrhythmia.

METHODS

Seven female dogs with electrodes chronically placed on the dorsal column of the spinal cord between T10 and T12 segments were studied in 2 randomized sessions (glucagon + sham-SCS, glucagon + SCS). SCS at T10 using a set of optimized stimulation parameters was performed for 30 minute immediately after glucagon injection. The antral manometry, electrogastrogram, and electrocardiogram were recorded to assess gastric contractions, gastric slow waves (GSW), and autonomic functions, respectively.

KEY RESULTS

(a) Compared to baseline, glucagon decreased antral motility index (MI) (6315 ± 565 vs 3243 ± 775, P < 0.001), reduced the percentage of normal GSW (89 ± 3% vs 58 ± 3%, P < 0.01), and increased sympathetic activity (0.25 ± 0 0.06 vs 0.60 ± 0.07, P < 0.01). (b) The sympathetic activity was negatively correlated with antral MI (r = -0.558; P < 0.01) and the percentage of gastric normal slow wave (r = -0.616; P < 0.01). (c) SCS prevented the glucagon-induced impairment in antral hypomotility (MI: 5770 ± 927 vs 5521 ± 1238, P > 0.05) and GSW abnormalities (% of normal waves: 84 ± 4% vs 79 ± 6%, P > 0.05) and sympathetic activity (0.27 ± 0.03 vs 0.33 ± 0.07, P > 0.05).

CONCLUSION

Spinal cord stimulation dramatically improves glucagon-induced impairment in gastric contractions and slow waves by inhibiting sympathetic activity.

Electroacupuncture via chronically implanted electrodes improves gastrointestinal motility by balancing sympathovagal activities in a rat model of constipation

Electroacupuncture (EA) has been reported for treating constipation in clinical studies. However, little is known of the possible mechanisms involved in the prokinetic effect of EA. The aim of this study was to investigate the effects and underlying autonomic mechanisms of EA via chronically implanted electrodes for constipation in rat induced by Loperamide (Lop). Lop was given to regular rats to induce constipation. EA was performed via a pair of electrodes chronically implanted at bilateral acupoint ST-36. Feces characteristics, gastric emptying, small intestinal transit, distal colon transit time (dCTT), and whole gut transit time (WGTT) were measured in various sessions with EA or sham EA in rats with constipation induced by Lop. Heart rate variability (HRV) derived from the electrocardiogram was analyzed to evaluate autonomic functions. The number of fecal pellets was reduced by 27% with Lop (P < 0.01) and normalized by 7-day EA. Similar results were also observed in pellet weight. In normal rats compared with sham EA, EA shortened dCTT by 74% (P < 0.05 vs. sham EA), increased small intestinal transit by 28% (P < 0.01) and gastric emptying by 27% (P < 0.05), and accelerated whole gut transit by 14% (P < 0.05). In Lop-treated rats, the dCTT and WGTT were prolonged by Lop and normalized by EA. Lop significantly decreased vagal activity and increased sympathetic nerve activity; however, EA reversed these effects. EA at ST-36 via chronically implanted electrodes improves Lop-induced constipation by enhancing GI motility via the autonomic mechanisms. NEW & NOTEWORTHY The findings of the present study suggest that the proposed electroacupuncture (EA) may have great therapeutic potential for treating patients with opioid-induced constipation. It was demonstrated that EA at ST-36 improved transit of every organ along the gut mediated via the autonomic mechanisms in normal rats and rats with Lop-induced constipation. It is advised to administrate EA daily instead of two or three times weekly as reported in most of the clinical studies.

Ameliorating effects and mechanisms of chronic electroacupuncture at ST36 in a rodent model of dyspepsia induced by cisplatin

BACKGROUND

Chemotherapy-associated dyspepsia syndrome (CADS) is among the most intensive side effects and critical concerns for patients with cancer. To investigate the effects and mechanisms of chronic electroacupuncture (EA) at ST36 on chemotherapy-associated dyspeptic symptoms (CADS) in rats.

METHODS

Cisplatin (8 mg/kg, ip) was given once to establish CADS model. EA or sham-EA treatment was then performed one hour daily for 21 days.

KEY RESULTS

(a) EA treatment decreased kaolin intake within 24 hours (1.67 ± 0.23 g vs 2.36 ± 0.37 g in sham-EA, P < 0.05); EA increased food intake (9.43 ± 2.28 vs 4.32 ± 1.26 in sham-EA, P < 0.05) and cisplatin-induced reduction of body weight (426.38 ± 13.25 vs 407.92 ± 13.26 in sham-EA, P = 0.05). (b) The incidence of normal behavioral satiety sequence (53%) in EA group was greater than that in sham-EA (32%) group (X²  = 17.68, P < 0.01). (c) EA increased the percentage of normal gastric slow waves (82.6 ± 5.98 vs 22.8 ± 1.90 in sham-EA, P < 0.05). (d) EA normalized cisplatin delayed gastric emptying (71.3% ± 6.8% vs 44.6% ± 11.2% in control, P < 0.05). (e) EA decreased ratio of heart rate variability (0.30 ± 0.03 vs 0.56 ± 0.05 in sham-EA, P < 0.05). (f) EA decreased fasting ghrelin, glucagon-like peptide-1 and peptide YY (P < 0.01 vs sham-EA for all).

CONCLUSIONS AND INFERENCES

Chronic EA ameliorates dyspepsia symptom and improves gastric dysmotility induced by Cisplatin, mediated via the vagal and gastrointestinal hormonal mechanisms.

Effect of Electroacupuncture on the Activity of Corticotrophin-Releasing Hormone Neurons in the Hypothalamus and Amygdala in Rats Exposed to Restraint Water-Immersion Stress

Objective

To investigate the effects of electroacupuncture (EA) treatment on gastric mucosal lesions and the activity of corticotrophin-releasing hormone (CRH) neurons in the paraventricular nucleus (PVN) of the hypothalamus and the central nucleus of the amygdala (CNA) in a rat model of restraint water-immersion stress (RWIS).

Methods

24 male Wistar rats were randomly divided into three groups: normal, RWIS, and RWIS+EA (n=8 per group). Rats in the RWIS group and RWIS+EA group received RWIS for 3 hours. For rats in the RWIS+EA group, EA was applied at ST36 in the bilateral hind legs for 30 min before RWIS. Rats in the normal group did not receive stressors or EA treatment. The gastric mucosal lesions of each rat were evaluated by the erosion index (EI) according to the methods of Guth. The activity of CRH neurons in the PVN and CNA was measured by a dual immunohistochemical test for Fos and CRH in the brain sections.

Results

RWIS induced serious gastric mucosal lesions. The mean gastric EI was significantly decreased in the RWIS+EA group versus the RWIS group (P=0.005). Stress induced significant activation of CRH neurons in the PVN and CNA compared with the normal group (P<0.001 for both). The mean number of Fos+CRH immunoreactive neurons in the PVN and CNA were both decreased inRWIS+EA versusRWIS groups (P<0.001 and P=0.001).

Conclusions

EA at ST36 can ameliorate RWIS-induced gastric mucosal lesions and suppress the Fos expression of CRH neurons in the PVN and CNA, suggesting a potentially therapeutic role for EA in stress-related gastric disorders.

Electroacupuncture via chronically implanted electrodes improves gastric dysmotility mediated by autonomic-cholinergic mechanisms in a rodent model of functional dyspepsia

BACKGROUND

Electroacupuncture (EA) has been shown to be effective in reducing symptoms in patients with functional dyspepsia (FD). However, its mechanisms remain largely unknown. The aim of this study was to investigate mechanisms of the prokinetic effects of EA in a rodent model of FD.

METHODS

A FD model was established by neonatal treatment of iodoacetamide (IA). Eight weeks later, the rats were implanted with electrodes in the stomach for the measurement of gastric slow waves (GSW) and electrodes into acupoints ST36 for EA. Autonomic functions were assessed by the spectral analysis of heart rate variability.

KEY RESULTS

(i) The IA-treated rats ("FD" rats) showed increased dysrhythmia in both fasting and fed states (P < .01) as well as during rectal distention (P < .02). EA reduced the percentage of dysrhythmia (P < .05 for both fasting and fed) and normalized RD-induced impairment in GSW in "FD" rats. Atropine blocked the effect of EA on GSW. (ii) "FD" rats showed delayed gastric emptying (P = .001 vs control) that was accelerated with EA (P = .01, vs sham-EA). (iii) "FD" rats showed increased plasma norepinephrine (P = .006, vs control) that was suppressed with EA (P = .003) and reduced vagal activity that was improved with EA.

CONCLUSIONS AND INFERENCES

Gastric motility (GSW and GE) is impaired in rats treated with IA, possibly attributed to impaired autonomic functions. EA improves GSW and accelerates GE mediated via the autonomic and cholinergic mechanisms.

Preventive effects of transcutaneous electrical acustimulation on ischemic stroke-induced constipation mediated via the autonomic pathway

The aim of this study was to explore the preventive effect and possible mechanisms of transcutaneous electrical acustimulation (TEA) on stroke-induced constipation. A total of 86 ischemic stroke patients were randomly allocated to 2-wk TEA or sham-TEA group. Bowel dairy and Bristol Stool Form Scale were recorded daily. Constipation and dyspeptic symptom assessment was performed at the end of the 14-day treatment. Electrocardiogram was recorded for the assessment of autonomic function. The correlation between autonomic function at admission and stroke severity was assessed. The univariate and multivariate regression analyses were performed to investigate the risk factors for stroke-induced constipation. The cumulative incidence of stroke-induced constipation was 68.2% at the acute stage. Sympathetic nerve activity at admission was positively correlated with stroke severity ( R = 0.47, P < 0.001). Sympathetic nerve activity and stroke severity were independent risk factors for stroke-induced constipation. TEA decreased cumulative incidence of stroke-induced constipation (42.9 vs. 68.2%, P = 0.029). TEA significantly increased frequency of bowel movements (4.5 vs. 5.5, P = 0.001) and spontaneous bowel movements (3.0 vs. 4.5, P = 0.003) per week. TEA decreased straining defecations (0.2 vs. 0, P < 0.001) and laxative use (1 vs. 0, P < 0.001). TEA improved stool consistency and patients' quality of life ( P < 0.05, resp.). TEA increased vagal activity ( P < 0.001 vs. baseline) and decreased sympathetic activity ( P < 0.001 vs. baseline). Ischemic stroke patients are predisposed to autonomic function imbalance. TEA was effective in the prevention of stroke-induced constipation, and the effect was possibly mediated via the autonomic function. NEW & NOTEWORTHY This study illustrated that the brain-gut dysfunction, primarily autonomic function imbalance, was correlated with the stroke-induced constipation. This was the first study to report that transcutaneous electrical acustimulation had a preventive effect on stroke-induced constipation, suggesting a potential novel therapy for bowel problem management. The effect was possibly mediated via the autonomic function.

Needleless Transcutaneous Electrical Acustimulation: A Pilot Study Evaluating Improvement in Post-Operative Recovery

BACKGROUND

Functional gastrointestinal disturbance occurs after abdominal surgeries and could last for an extended period of time in some cases. This study was designed (1) to evaluate the effects of needleless transcutaneous electrical acustimulation (TEA) on postoperative recovery, and (2) to investigate the mechanisms involving autonomic function in postoperative patients after removal of gastrointestinal cancers.

METHODS

Forty-two patients (33 male, age: 69.5 ± 1.5 years) scheduled for abdominal surgical removal of gastrointestinal cancers were randomized to TEA (n = 21) and sham-TEA (n = 21). TEA was performed via acupoints ST36 and PC6 1 h twice daily from the postoperative day (POD) 1 to day 3. Sham-TEA was performed at non-acupoints.

RESULTS

(1) TEA improved major postoperative symptoms by about 30%, including a reduction in time to defecation by 31.7% (P < 0.01 vs. sham-TEA), time to first flatus by 35.9% (P < 0.001), time to ambulation by 42.8% (P < 0.01), time to resuming diet by 26.5% (P < 0.01) and hospital stay by 30% (P < 0.05) as well as pain score by 50% (P < 0.01). (2) TEA significantly increased vagal activity (P < 0.001) and decreased sympathetic activity on POD 4 (P < 0.001) compared with POD 1 as well as the serum level of NE (P < 0.05). (3) The vagal activity, high frequency assessed from the spectral analysis of heart rate variability, was negatively correlated with time to resuming diet, whereas the sympathetic measurement, serum norepinephrine was positively correlated with time to resuming diet and time to flatus. (4) TEA but not sham-TEA decreased TNF-α by 17.4% from POD 1 to POD 4. (5) TEA was an independent predictor of a shorter hospital stay.

CONCLUSIONS

Needleless TEA improves major postoperative symptoms by enhancing vagal and suppressing sympathetic activities.

Inhibitory Effects and Mechanisms of Electroacupuncture via Chronically Implanted Electrodes on Stress-Induced Gastric Hypersensitivity in Rats With Neonatal Treatment of Iodoacetamide

BACKGROUND

Stress is considered an independent factor causing and aggravating gastrointestinal symptoms, including visceral pain. The aim of this study was to investigate effects and mechanisms of electroacupuncture (EA) on stress-induced gastric hypersensitivity in rats treated with neonatal iodoacetamide mimicking human functional dyspepsia (FD).

METHODS

Neonatal rats were treated with gavage of 0.2 mL of 0.1% iodoacetamide in 2% sucrose daily for six days starting on tenth day after birth. The control group was given 0.2 mL of 2% sucrose. When the rats were eight weeks old, acute restraint stress was performed on them for 90 min. EA at ST36 (ZuSanLi) was performed during the acute stress or 30 min after the stress. Adrenoceptor blocking drugs (propranolol and phentolamine) were injected intraperitoneally 30 min before acute restraint stress to explore possible sympathetic mechanisms. Visceral-motor responses to gastric distention were assessed by electromyogram (EMG).

RESULTS

1) Stress-induced gastric hypersensitivity was significantly more severe in the FD rats, compared to the control rats. It was blocked by the adrenoceptor antagonists. 2) EA inhibited stress-induced gastric hypersensitivity; the preventive effect of EA (given during stress) was more remarkable than the curative effect (given after stress). Stress resulted in a higher sympathovagal ratio and this was suppressed by EA.

CONCLUSIONS

Rats treated with neonatal iodoacetamide mimicking FD are more vulnerable to stress. Stress-induced gastric hypersensitivity can be prevented or suppressed by EA at ST36 via the restoration of sympathovagal balance.

Electroacupuncture ameliorates abnormal defaecation and regulates corticotrophin-releasing factor in a rat model of stress

Objective

To examine the effect of electroacupuncture (EA) treatment on abnormal defaecation in a rat model of chronic heterotypic stress (CHS) and investigate the underlying mechanisms.

Methods

20 male Sprague-Dawley rats were randomly divided into three groups: normal (n=6), CHS (n=7), and CHS+EA (n=7). Rats in the CHS group and CHS+EA groups received four different types of stressors for 7 days. For rats in the CHS+EA group, EA was applied at ST36 in the bilateral hind legs for 30 min before each stress-loading session. Rats in the normal group did not receive stressors or EA treatment. The faecal pellets of each rat were collected and weighed at a fixed time every day. Protein expression of corticotrophin-releasing factor (CRF) in the hypothalamus and colorectal tissues was measured by Western blotting at the end of the experiment on the 7th day.

Results

After 7 consecutive days of CHS, the number of faecal pellets, faecal wet weight, and faecal water content were significantly increased in the CHS group compared with the normal group (p=0.035, p=0.008 and p=0.008, respectively). All three parameters were significantly decreased in CHS+EA versus CHS groups (p=0.030, p=0.011 and p=0.006, respectively). Stress significantly increased CRF expression in both the hypothalamus and colorectal tissues. The excessive CRF responses seen following CHS were significantly suppressed by EA treatment.

Conclusions

EA treatment can ameliorate stress loading induced abnormal defaecation in rats and decrease protein expression of CRF centrally (hypothalamus) and peripherally (colorectal tissues), suggesting a potentially therapeutic role for EA in stress-related responses.

Effects of Transcutaneous Electrical Acustimulation on Refractory Gastroesophageal Reflux Disease

Objective. To investigate effects and possible mechanisms of transcutaneous electrical acustimulation (TEA) performed by a wearable watch-size stimulator for refractory gastroesophageal reflux disease (RGERD). Methods. Twenty patients diagnosed as RGERD were enrolled in the study and randomly divided into four groups: esomeprazole group (Group A), esomeprazole combined with TEA group (Group B), esomeprazole combined with sham-TEA group (Group C), and esomeprazole combined with domperidone group (Group D). HRM and 24 h pH-impedance monitoring and GerdQ score were used to measure related indexes before and after treatment. Results. (1) TEA significantly increased LESP, compared with PPI treatment only or PPI plus sham-TEA. After pairwise comparison, LESP of Group B was increased more than Group A (P = 0.008) or Group C (P = 0.021). (2) PPI plus TEA decreased not only the number of acid reflux episodes but also the number of weak acid reflux episodes (P = 0.005). (3) Heartburn and reflux symptoms were improved more with PPI + TEA than with PPI treatment only or PPI plus sham-TEA (GerdQ scores, P = 0.001). Conclusion. TEA can improve symptoms in RGERD patients by increasing LESP and decreasing events of weak acid reflux and acid reflux; addition of TEA to esomeprazole significantly enhances the effect of TEA.

Use of an allostatic neurotechnology by adolescents with postural orthostatic tachycardia syndrome (POTS) is associated with improvements in heart rate variability and changes in temporal lobe electrical activity

Autonomic dysregulation and heterogeneous symptoms characterize postural orthostatic tachycardia syndrome (POTS). This study evaluated the effect of high-resolution, relational, resonance-based, electroencephalic mirroring (HIRREM^®), a noninvasive, allostatic neurotechnology for relaxation and auto-calibration of neural oscillations, on heart rate variability, brain asymmetry, and autonomic symptoms, in adolescents with POTS. Seven subjects with POTS (three males, ages 15–18) underwent a median of 14 (10–16) HIRREM sessions over 13 (8–17) days. Autonomic function was assessed from 10-min continuous heart rate and blood pressure recordings, pre- and post-HIRREM. One-minute epochs of temporal high-frequency (23–36 Hz) brain electrical activity data (T3 and T4, eyes closed) were analyzed from baseline HIRREM assessment and subsequent sessions. Subjects rated autonomic symptoms before and after HIRREM. Four of seven were on fludrocortisone, which was stopped before or during their sessions. Heart rate variability in the time domain (standard deviation of the beat-to-beat interval) increased post-HIRREM (mean increase 51 %, range 10–143, p = 0.03), as did baroreflex sensitivity (mean increase in high-frequency alpha 65 %, range −6 to 180, p = 0.05). Baseline temporal electrical asymmetry negatively correlated with change in asymmetry from assessment to the final HIRREM session (p = 0.01). Summed high-frequency amplitudes at left and right temporal lobes decreased a median of 3.8 μV (p = 0.02). There was a trend for improvements in self-reported symptoms related to the autonomic nervous system. Use of HIRREM was associated with reduced sympathetic bias in autonomic cardiovascular regulation, greater symmetry and reduced amplitudes in temporal lobe high-frequency electrical activity, and a trend for reduced autonomic symptoms. Data suggest the potential for allostatic neurotechnology to facilitate increased flexibility in autonomic cardiovascular regulation, possibly through more balanced activity at regions of the neocortex responsible for autonomic management.

Clinical trial registry “Tilt Table with Suspected postural orthostatic tachycardia syndrome (POTS) Subjects,” Protocol Record: WFUBAHA01.