Home-Based Transcutaneous Neuromodulation Improved Constipation via Modulating Gastrointestinal Hormones and Bile Acids

The associations between modifiable risk factors and constipation: a comprehensive mendelian randomization study

OBJECTIVE

Early identification of modifiable risk factors is crucial for the prevention of constipation. This study systematically investigated the relationship between genetically predicted modifiable risk factors and constipation.

METHODS

The inverse variance weighting (IVW) method was employed as the primary analytical approach. For similar exposure indicators, the multivariate Mendelian randomization (MVMR) method was used to adjust for potential biases in univariate MR analysis. The robustness of the results was further evaluated using the MR-Egger intercept test, Cochran's Q test, and leave-one-out analysis. Bonferroni correction was applied to reduce the false positive rate in the results.

RESULTS

The IVW analysis indicated a significant causal association between genetically predicted gastroesophageal reflux disease [OR (95% CI) = 1.192 (1.079-1.315), P = 0.0005], atorvastatin use [OR (95% CI) = 16.995 (3.327-86.816), P = 0.0007], and constipation. Additionally, there was a potential causal association between education level [OR (95% CI) = 0.859 (0.767-0.964), P = 0.009], major depressive disorder [OR (95% CI) = 1.206 (1.041-1.399), P = 0.013], hypothyroidism [OR (95% CI) = 2.299 (1.327-3.985), P = 0.003], and aspirin use [OR (95% CI) = 4.872 (1.174-20.221), P = 0.029] with constipation. No causal associations were found for the other included indicators. Sensitivity analysis demonstrated the absence of evidence for heterogeneity and pleiotropy in any positive results.

CONCLUSION

This study identified several risk factors that could be targeted for the prevention of constipation, offering valuable insights for public health policies.

Posterior tibial nerve electrical stimulation in chronic constipation: a systematic review and meta-analysis

Aim

A systematic review and meta-analysis were performed to investigate posterior tibial nerve electrical stimulation application methods in patients with chronic constipation.

Background

Posterior tibial nerve electrical stimulation is a management procedure for chronic constipation.

Methods

A comprehensive search was conducted on Ovid, PubMed, Scopus, ProQuest, Web of Science, and The Cochrane Library based on the PICO formation of the study. All randomized controlled trials and quasi-experimental studies in which patients with chronic constipation were treated with transcutaneous tibial nerve stimulation (TTNS) or percutaneous tibial nerve stimulation (PTNS) were included in this study. Two independent reviewers screened all titles, abstracts, and full texts. The selected studies' quality was assessed critically using the Joanna Briggs Institute checklists. The data synthesis was conducted using Review Manager Software.

Results

Out of 1016 records, 11 studies were included in this study. The results showed that TTNS was effective in improving constipation symptoms (SMD: -1.52, CI 95%: -2.81 to -0.22, p< 0.0001) and reducing defecation time of patients with chronic constipation (SMD: -0.86, CI 95%: -1.60 to -0.13, p= 0.17). Additionally, PTNS was found to improve the quality of life of these patients (SMD: -1.32, CI 95%: -2.05 to -0.59, p< 0.00001).

Conclusion

Both TTNS and PTNS can be effective interventions for chronic constipation. To suggest a definitive and standard treatment plan, further research is needed to determine optimal parameters for TTNS and PTNS applications.

Electroacupuncture Alleviates Functional Constipation in Mice by Activating Enteric Glial Cell Autophagy via PI3K/AKT/mTOR Signaling

OBJECTIVE

To investigate autophagy-related mechanisms of electroacupuncture (EA) action in improving gastrointestinal motility in mice with functional constipation (FC).

METHODS

According to a random number table, the Kunming mice were divided into the normal control, FC and EA groups in Experiment I. The autophagy inhibitor 3-methyladenine (3-MA) was used to observe whether it antagonized the effects of EA in Experiment II. An FC model was established by diphenoxylate gavage. Then the mice were treated with EA stimulation at Tianshu (ST 25) and Shangjuxu (ST 37) acupoints. The first black stool defecation time, the number, weight, and water content of 8-h feces, and intestinal transit rate were used to assess intestinal transit. Colonic tissues underwent histopathological assessment, and the expressions of autophagy markers microtubule-associated protein 1 light chain 3 (LC3) and Beclin-1 were detected by immunohistochemical staining. The expressions of phosphoinositide 3-kinases (PI3K)-protein kinase B (AKT)-mammalian target of rapamycin (mTOR) signaling pathway members were investigated by Western blot and quantitative reverse transcription-polymerase chain reaction, respectively. The relationship between enteric glial cells (EGCs) and autophagy was observed by confocal immunofluorescence microscopy, localization analysis, and electron microscopy.

RESULTS

EA treatment shortened the first black stool defecation time, increased the number, weight, and water content of 8-h feces, and improved the intestinal transit rate in FC mice (P<0.01). In terms of a putative autophagy mechanism, EA treatment promoted the expressions of LC3 and Beclin-1 proteins in the colonic tissue of FC mice (P<0.05), with glial fibrillary acidic protein (GFAP) and LC3 significantly colocalized. Furthermore, EA promoted colonic autophagy in FC mice by inhibiting PI3K/AKT/mTOR signaling (P<0.05 or P<0.01). The positive effect of EA on intestinal motility in FC mice was blocked by 3-MA.

CONCLUSION

EA treatment can inhibit PI3K/AKT/mTOR signaling in the colonic tissues of FC mice, thereby promoting EGCs autophagy to improve intestinal motility.

The Pathological Effects of Circulating Hydrophobic Bile Acids in Alzheimer's Disease

Recent clinical studies have revealed that the serum levels of toxic hydrophobic bile acids (deoxy cholic acid, lithocholic acid [LCA], and glycoursodeoxycholic acid) are significantly higher in patients with Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI) when compared to control subjects. The elevated serum bile acids may be the result of hepatic peroxisomal dysfunction. Circulating hydrophobic bile acids are able to disrupt the blood-brain barrier and promote the formation of amyloid-β plaques through enhancing the oxidation of docosahexaenoic acid. Hydrophobic bile acid may find their ways into the neurons via the apical sodium-dependent bile acid transporter. It has been shown that hydrophobic bile acids impose their pathological effects by activating farnesoid X receptor and suppressing bile acid synthesis in the brain, blocking NMDA receptors, lowering brain oxysterol levels, and interfering with 17β-estradiol actions such as LCA by binding to E2 receptors (molecular modelling data exclusive to this paper). Hydrophobic bile acids may interfere with the sonic hedgehog signaling through alteration of cell membrane rafts and reducing brain 24(S)-hydroxycholesterol. This article will 1) analyze the pathological roles of circulating hydrophobic bile acids in the brain, 2) propose therapeutic approaches, and 3) conclude that consideration be given to reducing/monitoring toxic bile acid levels in patients with AD or aMCI, prior/in combination with other treatments.

Clinical efficacy and mechanism of transcutaneous neuromodulation on ineffective esophageal motility in patients with gastroesophageal reflux disease

BACKGROUND

Esophageal motility disorder is one of the pathogenesis of gastroesophageal reflux disease (GERD). The clinical and functional relationship between the ineffective esophageal motility (IEM) and GERD have been found. PPI is a widely used drug of this diaease, but some patients have poor efficacy. The purpose of this study was to investigate the efficacy and possible mechanism of Transcutaneous Neuromodulation in these patients.

METHODS

Fifty-six patients with GERD with IEM were enrolled and randomly divided into two groups, one group was TN ST-36 group, the other group was sham TN group. The GERD questionnaire (GerdQ), quality of life score, MOS item short from health survey (SF-36), Hospital Anxiety and Depression Scale (HADS) were used to assess the severity of symptoms. High-resolution esophageal manometry (HRM) test was performed to assess low esophageal sphincter (LES) pressure and distal contractile integral (DCI). The heart rate variability (HRV) test was performed to assess autonomic nervous function.

KEY RESULTS

Compared with sham TN, chronic TN treatment decreased the GERD-Q score (p < 0.001). The anxiety score (p = 0.058) and depression score (p = 0.156) were decreased, but there were no statistical differences. Chronic TN treatment also significantly improved the quality of life of patients, mainly in physical function, physical pain, overall health, vitality, social function, emotional function, and mental health. Acute TN treatment increased the DCI (p < 0.001) and LES pressure (p < 0.001) significantly and decreased the combined percentage of failed and weak peristalsis (p < 0.001). Concurrently, acute TN enhanced vagal activity (p < 0.001).

CONCLUSIONS AND INFERENCES

IEM is an important link in the pathogenesis of GERD. Chronic TN treatment can significantly improve the clinical symptoms of patients. Acute TN treatment can significantly increase LES pressure and DCI and reduce the frequency of esophageal lost peristalsis and weak peristalsis. The improvement of esophageal motility in GERD patients with IEM by TN treatment may be related to the regulation of autonomic nervous function.

Effects of Electroacupuncture for Opioid-Induced Constipation in Patients With Cancer in China: A Randomized Clinical Trial

IMPORTANCE

Opioid-induced constipation (OIC) is prevalent among patients treated with opioids for cancer pain. Safe and effective therapies for OIC in patients with cancer remain an unmet need.

OBJECTIVE

To determine the efficacy of electroacupuncture (EA) for OIC in patients with cancer.

DESIGN, SETTING, AND PARTICIPANTS

This randomized clinical trial was conducted at 6 tertiary hospitals in China among 100 adult patients with cancer who were screened for OIC and enrolled between May 1, 2019, and December 11, 2021.

INTERVENTIONS

Patients were randomized to receive 24 sessions of EA or sham electroacupuncture (SA) over 8 weeks and then were followed up for 8 weeks after treatment.

MAIN OUTCOMES AND MEASURES

The primary outcome was the proportion of overall responders, defined as patients who had at least 3 spontaneous bowel movements (SBMs) per week and an increase of at least 1 SBM from baseline in the same week for at least 6 of the 8 weeks of the treatment period. All statistical analyses were based on the intention-to-treat principle.

RESULTS

A total of 100 patients (mean [SD] age, 64.4 [10.5] years; 56 men [56.0%]) underwent randomization; 50 were randomly assigned to each group. Among them, 44 of 50 patients (88.0%) in the EA group and 42 of 50 patients (84.0%) in the SA group received at least 20 (≥83.3%) sessions of treatment. The proportion of overall responders at week 8 was 40.1% (95% CI, 26.1%-54.1%) in the EA group and 9.0% (95% CI, 0.5%-17.4%) in the SA group (difference between groups, 31.1 percentage points [95% CI, 14.8-47.6 percentage points]; P < .001). Compared with SA, EA provided greater relief for most OIC symptoms and improved quality of life among patients with OIC. Electroacupuncture had no effects on cancer pain and its opioid treatment dosage. Electroacupuncture-related adverse events were rare, and, if any, all were mild and transient.

CONCLUSIONS AND RELEVANCE

This randomized clinical trial found that 8-week EA treatment could increase weekly SBMs with a good safety profile and improve quality of life for the treatment of OIC. Electroacupuncture thus provided an alternative option for OIC in adult patients with cancer.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03797586.

Gut microbiota plays a role in irritable bowel syndrome by regulating 5-HT metabolism

Irritable bowel syndrome (IBS) is a common chronic functional gastrointestinal disorder. Brain-gut-microbiota axis dysfunction is an important pathogenic factor for IBS, in which neurotransmitters and gut microbes play key roles. The gastrointestinal tract contains large amounts of serotonin (5-hydroxytryptamine, 5-HT), a neurotransmitter that has been strongly linked to IBS-related symptoms. More than 90% of serotonin is synthesized in the gut by enterochromaffin cells (ECs), and certain intestinal flora can affect the occurrence and development of IBS by regulating 5-HT and its metabolism. In this review, we will discuss the role of gut microbiota in IBS by regulating 5-HT.

Electroacupuncture vs Prucalopride for Severe Chronic Constipation: A Multicenter, Randomized, Controlled, Noninferiority Trial

INTRODUCTION

This multicenter, randomized, noninferiority trial compared electroacupuncture with prucalopride for the treatment of severe chronic constipation (SCC).

METHODS

Participants with SCC (≤ 2 mean weekly complete spontaneous bowel movements [CSBMs]) were randomly assigned to receive either 28-session electroacupuncture over 8 weeks with follow-up without treatment over 24 weeks or prucalopride (2 mg/d before breakfast) over 32 weeks. The primary outcome was the proportion of participants with ≥3 mean weekly CSBMs over weeks 3-8, based on the modified intention-to-treat population, with -10% as the noninferior margin.

RESULTS

Five hundred sixty participants were randomized, 280 in each group. Electroacupuncture was noninferior to prucalopride for the primary outcome (36.2% vs 37.8%, with a difference of -1.6% [95% confidence interval, -8% to 4.7%], P < 0.001 for noninferiority); almost the same results were found in the per-protocol population. The proportions of overall CSBM responders through weeks 1-8 were similar in the electroacupuncture and prucalopride groups (24.91% vs 25.54%, with a difference of -0.63% [95% confidence interval, -7.86% to 6.60%, P = 0.864]). Except during the first 2-week treatment, no between-group differences were found in outcomes of excessive straining, stool consistency, and quality of life. Adverse events occurred in 49 (17.69%) participants in the electroacupuncture group and 123 (44.24%) in the prucalopride group. One non-treatment-related serious adverse event was recorded in the electroacupuncture group.

DISCUSSION

Electroacupuncture was noninferior to prucalopride in relieving SCC with a good safety profile. The effects of 8-week electroacupuncture could sustain for 24 weeks after treatment. Electroacupuncture is a promising noninferior alternative for SCC (see Visual Abstract, http://links.lww.com/AJG/B776).

Curative Effect and Mechanism of Guiren Runchang Granules on Morphine-Induced Slow Transit Constipation in Mice

Recent studies have identified the curative effects of traditional Chinese medicine for constipation. The mechanism of action of Guiren Runchang granules (GRGs) in the treatment of slow transit constipation (STC) was evaluated in this study. Here, we assessed the efficacy of GRG by comparing the differences in fecal characteristics, stool weight, and intestinal transit rate (ITR) among 6 groups (n = 12/group), which were administered three concentrations of GRG, mosapride, and saline. The influence of GRG on the SCF/c-kit pathway, AQP4, and serum motilin of mice was assessed through ELISA, western blot, and immunohistochemical analysis. The dry weight of mouse feces at 24 hr and ITR in the MD (medium-dose GRG; 9.44 g/kg/d) and HD (high-dose GRG; 18.88 g/kg/d) groups was higher than that in the MC (model control) group. The serum motilin of morphine-induced mice level was lower in the MC group than in the NC (normal control) group, and this condition was improved in the HD group. The HD group expressed significantly higher levels of SCF and c-kit protein but lower levels of AQP4 and simultaneously presented more SCF-positive and c-kit-positive cells. However, no differences in the serum SCF level were found among the six groups. Certain concentrations of GRG are effective in STC mice, the potential mechanism of which may be associated with repairing the SCF/c-kit pathway and reducing the expression of AQP4 in the colon. GRG improved the serum motilin level but had no influence on the serum SCF level.

The role of tibial nerve stimulation for enhanced postoperative recovery after colorectal surgery: a double-blind, parallel-group, randomized controlled trial

BACKGROUND

Postoperative ileus (POI) is the most common cause of prolonged hospital stay following abdominal surgery, despite an optimized enhanced recovery after surgery (ERAS) program. The aim of the study was to evaluate the role of postoperative transcutaneous electrical tibial nerve stimulation (TTNS) in the recovery of bowel function and in shortening hospital stay after colonic resection.

METHODS

Patients having elective laparoscopic colonic surgery within an ERAS program at our institution between June 2016 and June 2019 were enrolled and randomly assigned to a treatment protocol with TTNS or sham electrical stimulation. The primary endpoint was the time of recovery of gastrointestinal motility, measured as the first passage of stool. Secondary endpoints included: first passage of flatus, length of hospital stay, and complication rate related to the use of TTNS.

RESULTS

One hundred and seventy patients who had right hemicolectomy (median age 71 years (range 43-89 years); 47.5% women) and 170 patients who had left colectomy (median age 67 years range (37-92 years); 41.5% women) were enrolled. The only factor significantly affected by TTNS was time to first passage of flatus after right hemicolectomy (reduced from 46 to 33 h, p = 0.04). However, if only patients with low compliance to early oral nutrition (63 of 340; 18.5%) were considered, a statistically significant difference in time until first flatus (p < 0.01) and first bowel movement (p < 0.0001) and a shorter time until discharge (median 5 vs 7 days) were found in both left and right colectomies groups, respectively.

CONCLUSIONS

TTNS may have a positive effect on gastrointestinal tract motility and recovery from POI after colorectal surgery in a selected group, who has low compliance with an ERAS program, without increasing the risk of complications.

Transcutaneous Neuromodulation improved inflammation and sympathovagal ratio in patients with primary biliary ssscholangitis and inadequate response to Ursodeoxycholic acid: a pilot study

Background

At present, ursodeoxycholic acid (UDCA) is internationally recognized as a therapeutic drug in clinic. However, about 40% Primary Biliary Cholangitis (PBC) patients are poor responders to UDCA. It has been demonstrated that Transcutaneous Neuromodulation (TN) can be involved in gut motility, metabolism of bile acids, immune inflammation, and autonomic nerve. Therefore, this study aimed to explore the effect of TN combined with UDCA on PBC and related mechanisms.

Methods

According to inclusion and exclusion criteria, 10 healthy volunteers and 15 PBC patients were recruited to control group and TN group, respectively. PBC patients were alternately but blindly assigned to group A (TN combined with UDCA) and group B (sham-TN combined with UDCA), and a crossover design was used. The TN treatment was performed via the posterior tibial nerve and acupoint ST36 (Zusanli) 1 h twice/day for 2 weeks. T test and nonparametric test were used to analyze the data.

Results

1. TN combined with UDCA improved the liver function of PBC patients shown by a significant decrease of alkaline phosphatase and gamma-glutamyltransferase (γ-GT) (P < 0.05). 2. The treatment also decreased serum IL-6 levels (P < 0.05), but not the level of Tumor Necrosis Factor-α, IL-1β or IL-10. 3. TN combined with UDCA regulated autonomic function, enhanced vagal activity, and decreased the sympathovagal ratio assessed by the spectral analysis of heart rate variability (P < 0.05). 4. There was no change in 13 bile acids in serum or stool after TN or sham-TN.

Conclusions

TN cssombined with UDCA can significantly improve the liver function of PBC patients. It is possibly via the cholinergic anti-inflammatory pathway. TN might be a new non-drug therapy for PBC. Further studies are required.

Trial registration

The study protocol was registered in Chinese Clinical Trial Registry (number ChiCTR1800014633) on 25 January 2018.

Elobixibat for the treatment of constipation

INTRODUCTION

Chronic idiopathic constipation (CC) is highly prevalent worldwide. A subset of patients with CC have reduced fecal (and by inference, intra-colonic) bile acids (BA). Elobixibat, a locally-acting ileal bile acid transporter (IBAT) inhibitor, leads to increased BA delivery to the colon and represents a new class of treatment for CC. BAs accelerate colonic transit and increase colonic secretion. Therefore, IBAT inhibitors have potential to treat patients with CC. Areas covered: Rationale for IBAT inhibitor in therapeutics, and preclinical and clinical pharmacology of elobixibat: In vitro, elobixibat is a highly potent, selective IBAT inhibitor. In humans, elobixibat accelerated colonic transit. In phase 2A, 2B and 3 studies in CC, elobixibat was efficacious, well tolerated and safe. An open-label, phase 3 trial (52 weeks) confirmed the safety of elobixibat. Elobixibat reduces LDL cholesterol, increases serum GLP-1, and has potential in metabolic syndrome. Expert commentary: Uniquely among current treatments of CC, elobixibat stimulates both motor and secretory functions in the colon. These dual effects suggest that, when approved, elobixibat may be a first-line choice for constipation associated with colonic BA deficiency and a second-line treatment for all patients with CC and constipation-predominant irritable bowel syndrome. Further studies are required to confirm efficacy for relief of CC. Once approved, elobixibat will likely become a second-line choice for treatment of CC.