An orally administered magnoloside A ameliorates functional dyspepsia by modulating brain-gut peptides and gut microbiota

Mechanisms of neurocentral-eyestalk-intestinal immunotoxicity in whiteleg shrimp Litopenaeus vannamei under ammonia nitrogen exposure

Ammonia-N, as the most toxic nitrogenous waste, has high toxicity to marine animals. However, the interplay between ammonia-induced neuroendocrine toxicity and intestinal immune homeostasis has been largely overlooked. Here, a significant concordance of metabolome and transcriptome-based "cholinergic synapse" supports that plasma metabolites acetylcholine (ACh) plays an important role during NH4Cl exposure. After blocking the ACh signal transduction, the release of dopamine (DA) and 5-hydroxytryptamine (5-HT) in the cerebral ganglia increased, while the release of NPF in the thoracic ganglia and NE in the abdominal ganglia, and crustacean hyperglycemic hormone (CHH) and neuropeptide F (NPF) in the eyestalk decreased, finally the intestinal immunity was enhanced. After bilateral eyestalk ablation, the neuroendocrine system of shrimp was disturbed, more neuroendocrine factors, such as corticotropin releasing hormone (CRH), adrenocorticotropic-hormone (ACTH), ACh, DA, 5-HT, and norepinephrine (NE) were released into the plasma, and further decreased intestinal immunity. Subsequently, these neuroendocrine factors reach the intestine through endocrine or neural pathways and bind to their receptors to affect downstream signaling pathway factors to regulate intestinal immune homeostasis. Combined with different doses of ammonia-N exposure experiment, these findings suggest that NH4Cl may exert intestinal toxicity on shrimp by disrupting the cerebral ganglion-eyestalk axis and the cerebral ganglion-thoracic ganglion-abdominal ganglion axis, thereby damaging intestinal barrier function and inducing inflammatory response.

Effect of Chaihu-Shugan-San on functional dyspepsia and gut microbiota: A randomized, double-blind, placebo-controlled trial

ETHNOPHARMACOLOGICAL RELEVANCE

Chaihu-Shugan-San (CSS) is a classic traditional Chinese medicine (TCM) formula from the Ming Dynasty "Jingyue's Complete Works". In China, it is prevalent for the treatment of a wide range of ailments, with a particular emphasis on functional gastrointestinal disorders (FGIDs). Clinical evidence suggests that CSS has been found to be a highly effective therapeutic approach for the treatment of Functional Dyspepsia (FD), however, there is a limited amount of high-quality clinical evidence, particularly randomized, double-blind, placebo-controlled trials to support this claim.

AIM OF THE STUDY

To evaluate the therapeutic efficacy of Chaihu-Shugan-San (CSS) for treating functional dyspepsia (FD) by comparing it to placebos, as well as to investigate the impact of CSS on the gut microbiota in individuals diagnosed with FD.

MATERIALS AND METHODS

This was a randomized double-blind, placebo-controlled clinical trial implemented at Shuguang Hospital in Shanghai. Between May 2021 and December 2022, 94 participants satisfying the Rome IV diagnostic criteria for FD were enrolled. They were assigned randomly to either the CSS group or the placebo group, with an equal allocation ratio of 1:1. Patients in both groups received the intervention for four weeks. The primary outcome was the dyspepsia symptom scores evaluated by using single dyspepsia symptom scale (SDS) after four weeks of treatment. The secondary outcomes were the solid gastric empties rate measured by a barium strip method, Hamilton anxiety scale (HAMA), Hamilton depression scale (HAMD), and Functional dyspepsia Quality of life scale (FDDQL). In addition, after unblinding, 30 patients in the CSS group were randomly selected and divided into before and after treatment of the FD groups (FD1, FD2), and 30 healthy participants were selected as healthy control group (HC), and the gut microbiota was analyzed by 16S rRNA sequencing.

RESULTS

After four weeks of treatment, the SDS score exhibited a significant improvement in the CSS group compared to the placebo group (t = 4.882; P ＜0.001). The difference in barium strip gastric emptying rate in the CSS group showed a significant ascent compared to the control group (P < 0.01). The HAMA, HAMD, and FDDQL scores in the CSS group showed a statistically significant increase compared to the control group (all P < 0.01). The results of 16S rRNA sequencing revealed that FD patients had less diverse and abundant microbiota than the healthy people. Additionally, the application of CSS resulted in the modulation of certain bacterial populations, leading to both up-regulation and down-regulation of their quantities.

CONCLUSIONS

These findings suggested that CSS is more effective compared to a placebo in treating FD, relieves anxiety and depression, increases gastric emptying rate in FD patients, and that CSS also affects the bacterial community structure in FD patients.

TRIAL REGISTRATION

ChiCTR, ChiCTR2100045793. Registered 25 Mach 2021.

Xiao Cheng Qi Decoction, an Ancient Chinese Herbal Mixture, Relieves Loperamide-Induced Slow-Transit Constipation in Mice: An Action Mediated by Gut Microbiota

Xiao Cheng Qi (XCQ) decoction, an ancient Chinese herbal mixture, has been used in treating slow-transit constipation (STC) for years. The underlying action mechanism in relieving the clinical symptoms is unclear. Several lines of evidence point to a strong link between constipation and gut microbiota. Short-chain fatty acids (SCFAs) and microbial metabolites have been shown to affect 5-HT synthesis by activating the GPR43 receptor localized on intestinal enterochromaffin cells, since 5-HT receptors are known to influence colonic peristalsis. The objective of this study was to evaluate the efficacy of XCQ in alleviating clinical symptoms in a mouse model of STC induced by loperamide. The application of loperamide leads to a decrease in intestinal transport and fecal water, which is used to establish the animal model of STC. In addition, the relationship between constipation and gut microbiota was determined. The herbal materials, composed of Rhei Radix et Rhizoma (Rhizomes of Rheum palmatum L., Polygonaceae) 55.2 g, Magnoliae Officinalis Cortex (Barks of Magnolia officinalis Rehd. et Wils, Magnoliaceae) 27.6 g, and Aurantii Fructus Immaturus (Fruitlet of Citrus aurantium L., Rutaceae) 36.0 g, were extracted with water to prepare the XCQ decoction. The constipated mice were induced with loperamide (10 mg/kg/day), and then treated with an oral dose of XCQ herbal extract (2.0, 4.0, and 8.0 g/kg/day) two times a day. Mosapride was administered as a positive drug. In loperamide-induced STC mice, the therapeutic parameters of XCQ-treated mice were determined, i.e., (i) symptoms of constipation, composition of gut microbiota, and amount of short-chain fatty acids in feces; (ii) plasma level of 5-HT; and (iii) expressions of the GPR43 and 5-HT4 receptor in colon. XCQ ameliorated the constipation symptoms of loperamide-induced STC mice. In gut microbiota, the treatment of XCQ in STC mice increased the relative abundances of Lactobacillus, Prevotellaceae_UCG_001, Prevotellaceae_NK3B31_group, Muribaculaceae, and Roseburia in feces and decreased the relative abundances of Desulfovibrio, Tuzzerella, and Lachnospiraceae_ NK4A136_group. The levels of SCFAs in stools from the STC group were significantly lower than those the control group, and were greatly elevated via treatment with XCQ. Compared with the STC group, XCQ increased the plasma level of 5-HT and the colonic expressions of the GPR43 and 5-HT4 receptor, significantly. The underlying mechanism of XCQ in anti-constipation could be related to the modulation of gut microbiota, the increase in SCFAs, the increase in plasma 5-HT, and the colonic expressions of the GPR43 and 5-HT4 receptor. Our results indicate that XCQ is a potent natural product that could be a therapeutic strategy for constipation.

Probiotic-fermented Qushi decoction alleviates reserpine-induced spleen deficiency syndrome by regulating spleen function and gut microbiota dysbiosis

BACKGROUND

Spleen deficiency syndrome (SDS) is associated with elevated inflammatory factors and dysregulation of gastrointestinal motility hormones and intestinal microbiota. Qushi decoction (QD), a traditional formula, has not been reported using modern scientific research methods for changes in its probiotic fermented QD (FQD) composition and its potential mechanisms to alleviate SDS. Therefore, the aim of this study was to investigate the splenic protection of FQD in SDS rats by modulating gastrointestinal motility hormones and intestinal microbiota.

RESULTS

The results showed that FQD increased total polysaccharides, total protein, total flavonoids and the other active ingredients compared to QD, effectively improved splenic inflammation and apoptosis in SDS rats, and modulated gastrointestinal motility hormones to alleviate diarrhea and other symptoms. In addition, the dysregulation of the gut microbiota was reversed by increasing the levels of Bifidobacterium and decreasing the levels of Escherichia-Shigella and Proteobacteria, which may be related to the regulation of bacterial metabolites to alleviate SDS.

CONCLUSION

These results suggest that FQD is an effective formula for improving SDS. Our findings show that FQD beneficial to the implications for the treatment of SDS. © 2023 Society of Chemical Industry.

Systems biology strategy through integrating metabolomics and network pharmacology to reveal the mechanisms of Xiaopi Hewei Capsule improves functional dyspepsia

Functional dyspepsia (FD) is one of the more common functional disorders, with a prevalence of 20-25 %. It seriously affects the quality life of patients. Xiaopi Hewei Capsule (XPHC) is a classic formula originated from the Chinese Miao minority. Clinical studies have demonstrated that XPHC can effectively alleviate the symptoms of FD, but the molecular mechanism has not been elucidated. The purpose of this work is to investigate the mechanism of XPHC on FD by integrating metabolomics and network pharmacology. The mice models of FD were established, and gastric emptying rate, small intestine propulsion rate, serum level of motilin and gastrin were evaluate to study the interventional effect of XPHC on FD. Next, a metabolomics strategy has been developed to screen differential metabolites and related metabolic pathways induced by XPHC. Then, prediction of active compounds, targets and pathways of XPHC in treating FD were carried out by commonly used network pharmacological method. Finally, two parts of the results were integrated to investigate therapeutic mechanism of XPHC on FD, which were preliminary validated based on molecular docking. Thus, twenty representative different metabolites and thirteen related pathways of XPHC in treating FD were identified. Most of these metabolites were restored using modulation after XPHC treatment. The results of the network pharmacology analysis showed ten crucial compounds and nine hub genes related to the treatment of FD with XPHC. The further integrated analysis focused on four key targets, such as albumin (ALB), epidermal growth factor receptor (EGFR), tumor necrosis factor (TNF) and roto-oncogene tyrosine-protein kinase Src (SRC), and three representative biomarkers such as citric acid, L-leucine and eicosapentaenoic acid. Furthermore, molecular docking results showed that ten bioactive compounds from XPHC have good binding interactions with the four key genes. The functional enrichment analysis indicated that the potential mechanism of XPHC in treating FD was mainly associated with energy metabolism, amino acid metabolism, lipid metabolism, inflammatory reactions and mucosal repair. Our work confirms that network pharmacology-integrated metabolomics strategyis a powerful means to reveal the therapeutic mechanisms of XPHC improves FD, which contribute its further scientific research.

Developing the modified 4-item version of perceived stress scale for functional dyspepsia

BACKGROUND

To develop the modified 4-item version of Perceived Stress Scale (PSS) with a better reliability and validity than the 4-item version of PSS (PSS-4) in evaluating psychological stress in patients with functional dyspepsia (FD). The present study also aimed to explore the correlation between dyspepsia symptoms severity (DSS), anxiety, depression, somatization, quality of life (QoL), and psychological stress assessed by two approaches in FD.

METHODS

A total of 389 FD patients who met the Roman IV criteria completed the 10-item version of the PSS (PSS-10), and 4/10 items were selected by five methods, such as Cronbach's coefficient, exploratory factor analysis (EFA), correlation coefficient, discrete degree, and item analysis, to develop the modified PSS-4. The reliability and validity of the modified PSS-4 and the PSS-4 were compared by internal consistency, EFA, and confirmatory factor analysis (CFA). The correlation between psychological stress assessed by two approaches and DSS, anxiety, depression, somatization, and QoL was explored by Pearson's correlation coefficient and multiple linear regression analysis.

RESULTS

Cronbach's α coefficient of the modified PSS-4 and the PSS-4 was 0.855 and 0.848, respectively, and a common factor was extracted. The cumulative contribution rate of one factor to the overall variance for the modified PSS-4 and the PSS-4 was 70.194% and 68.698%, respectively. The model used for the modified PSS-4 showed that the values of the goodness-of-fit index (GFI) and the adjusted GFI (AGFI) were 0.987 and 0.933, respectively, indicating that the model fitted well. Psychological stress was correlated to DSS, anxiety, depression, somatization, and QoL as assessed by the modified PSS-4 and PSS-4. Multiple linear regression analysis revealed that psychological stress was correlated to somatization, as assessed by the modified PSS-4 (β = 0.251, P < 0.001) and PSS-4 (β = 0.247, P < 0.001). Psychological stress, DSS, and somatization were correlated to QoL, as assessed by the modified PSS-4 (β = 0.173, P < 0.001) and the PSS-4 (β = 0.167, P < 0.001).

CONCLUSIONS

The modified PSS-4 showed better reliability and validity, and psychological stress had a greater effect on the somatization and QoL of FD patients assessed by the modified PSS-4 than PSS-4. These findings were helpful for further investigation of the clinical application of the modified PSS-4 in FD.

Flavonoid extract of saffron by-product alleviates hyperuricemia via inhibiting xanthine oxidase and modulating gut microbiota

Hyperuricemia was associated with the overproduction or inadequate excretion of uric acid, while its association with gut microbiota has emerged although few studies were focused on it. Previously, we have reported a flavonoid extract from saffron floral bio-residues lowered uric acid in potassium oxonate-induced hyperuricemic mice. In this study, the impacts of the flavonoid extract on potassium oxonate-induced hyperuricemic rats were evaluated through its effects on serum, renal, intestinal uric acid, and xanthine oxidase activity. At the same time, the microbial and metabolic features of the flavonoid extract against hyperuricemia were explored using 16S rRNA sequencing techniques and serum metabolomics, respectively. According to the results, the flavonoid extract lowered serum and intestinal uric acid levels in hyperuricemic rats without kidney damage. On the one hand, it inhibited serum and liver xanthine oxidase activities and down-regulated the expression of hepatic xanthine oxidase. On the other hand, it ameliorated the hyperuricemia-associated gut microbiota dysbiosis and alleviated the disturbance of serum metabolome, especially of lipid and amino acid metabolites. The results suggested that the flavonoid extract of saffron floral bio-residues exerts a potent antihyperuricemia effect by inhibiting xanthine oxidase to decrease uric acid production and modulating gut microbiota related to host metabolism.

Intervention Effects of Okra Extract on Brain-Gut Peptides and Intestinal Microorganisms in Sleep Deprivation Rats

Objective

Okra, possessing various bioactive components, is used to treat different diseases. This study sought to estimate the intervention effects of okra extract (OE) on brain-gut peptides (BGPs) and intestinal microorganisms in sleep deprivation (SD) rats.

Methods

SD rat models were established using the modified multiple platform method and then treated with normal saline, diazepam tablets, or different doses of OE. Body weight and average daily water consumption of rats were recorded. Depressive behaviors of rats were assessed by the open field test and sucrose preference test. Serum levels of noradrenaline, melatonin, inflammatory factors (IL-1β/IL-6/TNF-α/IL-4/IL-10), and BGP indexes, including gastrin (GAS), motilin (MTL), 5-hydroxytryptamine (5-HT), cholecystokinin (CCK), and vasoactive intestinal peptide (VIP) were measured by ELISA. Additionally, the DNA relative contents of representative intestinal microorganisms in the collected rat feces were determined using RT-qPCR.

Results

SD decreased body weight and average daily water consumption and induced depressive behaviors as well as stress and inflammatory responses in rats. SD rats exhibited lowered GAS, MTL, 5-HT, and VIP but elevated CCK and showed diminished DNA relative contents of Bacteroidetes and probiotics (Bifidobacteria and Lactobacilli) but increased Clostridium perfringens. OE at different doses ameliorated the depressive behaviors and mitigated the stress and inflammatory responses in SD rats, raised the serum contents of GAS, MTL, 5-HT, and VIP, reduced CCK level, elevated the DNA relative contents of Bacteroidetes and probiotics, but diminished Clostridium perfringens. OE exhibited similar intervention effects to diazepam tablets (positive control).

Conclusion

OE exerts intervention effects on BGPs and intestinal microorganisms in SD rats.

Pharmacokinetics and metabolites of glycosides and lignans of the stem bark of Magnolia officinalis in functional dyspepsia and normal rats using LC-MS/MS

The stem bark of Magnolia officinalis is a traditional Chinese medicine for the treatment of abdominal distention and functional dyspepsia. The pharmacokinetics of three glycosides (magnoloside A, magnoloside B, and syringin) and two lignans (honokiol and magnolol) in both of normal and functional dyspepsia rats were firstly investigated by ultra-performance liquid chromatography-triple quadrupole mass spectrometry method and the influences of the coexisting compounds on the pharmacokinetic parameters of honokiol and magnolol were also studied. It was found that all of the five target compounds were quickly absorbed and eliminated in both of normal and functional dyspepsia rats, while, their residence time was significantly decreased in pathological states except magnoloside A. The coexisting compounds in the stem bark of M. officinalis significantly reduced absorption and increased elimination of honokiol in vivo. It's worth noticing that the volume of distribution of lignan was quite lower than that of glycoside. Moreover, the metabolic profiling of magnoloside A, honokiol, and magnolol in vivo was analyzed by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry method, from which three prototypes were identified and thirty five metabolites were putatively characterized, and eighteen unknown metabolites were reasonably characterized for the first time. The results indicated that sulfation and glucuronidation were the main metabolic pathways of honokiol and magnolol. This article is protected by copyright. All rights reserved.

Exploration of habitat-related chemomarkers for Magnoliae officinalis cortex applying both global and water-soluble components-based metabolomics method

BACKGROUND

The quality of traditional Chinese medicines (TCMs) has been closely related to their growth regions. The geo-herbalism of TCMs is just like the protected destination of origin on foodstuffs and wines, telling us the specific geographic regions could yield TCMs with superior quality. However, the impact of habitat on TCMs could hardly been indicated in current quality evaluation, defects were as follows: (1) few studies involved the effect of environmental factors, (2) more attentions were paid to several abundant compounds, while global components especially water-soluble compounds were prone to be ignored.

PURPOSE

A new integrated metabolomics analysis based on global and water-soluble components was proposed aiming to explore habitat-related chemomarkers for TCMs combined with correlation analysis to environmental factors. The geo-herbalism of Magnoliae officinalis cortex (MOC) was studied as an example.

METHODS

Multi-metabolomics approach based on UPLC/Q-TOF-MS and GC-MS combined with LC-2ECD were employed to analyze global components and accurately quantified water-soluble compounds, respectively. Meanwhile, decision tree, partial least squares discriminant analysis (PLS-DA) as well as hierarchical clustering analysis (HCA) heat map was applied to classify different samples and explore habitat-related chemomarkers. In addition, support vector machines model was used to verify the importance of screened out chemomarkers in predicting sample classification, and the impact of environmental factors on the markers were also demonstrated by correlation analysis.

RESULTS

By analyzing 148 batches of MOC samples from 21 habitats, 238 variables were picked and 84 of them were identified by UNIFI, meanwhile, seven water-soluble compounds were accurately quantified. Among them, thirteen markers including Var.1, magnolignan E, magnoloside N isomer, α-agarofuran, γ-eudesmol, β-eudesmol, magnolosides A, B, D, F, H, L and M were suggested importance in grouping Chuan-po and the other MOC samples. Support vector machines model also indicated well prediction performance with an accuracy of 96.97%. Most markers belong to water-soluble compounds and temperature and precipitation contributed to such chemical differences.

CONCLUSIONS

The proposed strategy based on multi-metabolomics analysis could aid exploration of habitat-related chemomarkers for TCMs. Meanwhile, the screened out water-soluble compounds could perform equivalent functions in recognition of Daodi medicinal materials (DMMs) and non-DMM samples compared to the global components to some extent.

The rich pharmacological activities of Magnolia officinalis and secondary effects based on significant intestinal contributions

ETHNOPHARMACOLOGICAL RELEVANCE

Magnolia officinalis Cortex (M. officinalis) is a traditional herbal drug widely used in Asian countries. Depending on its multiple biological activities, M. officinalis is used to regulate gastrointestinal (GI) motility, relieve cough and asthma, prevent cardiovascular and cerebrovascular diseases, and treat depression and anxiety.

AIM OF THE REVIEW

We aimed to review the abundant form of pharmacodynamics activity and potential mechanisms of action of M. officinalis and the characteristics of the internal processes of the main components. The potential mechanisms of local and distance actions of M. officinalis based on GI tract was provided, and it was used to reveal the interconnections between traditional use, phytochemistry, and pharmacology.

MATERIALS AND METHODS

Published literatures about M. officinalis and its main components were collected from several scientific databases, including PubMed, Elsevier, ScienceDirect, Google Scholar and Web of Science etc. RESULTS: M. officinalis was shown multiple effects including effects on digestive system, respiratory system, central system, which is consistent with traditional applications, as well as some other activities such as cardiovascular system, anticancer, anti-inflammatory and antioxidant effects and so on. The mechanisms of these activities are abundant. Its chief ingredients such as magnolol and honokiol can be metabolized into active metabolites in vivo, which can increase water solubility and bioavailability and exert pharmacological activity in the whole body. In the GI tract, M. officinalis and its main ingredient can regulate GI hormones and substance metabolism, protect the intestinal barrier and affect the gut microbiota (GM). These actions are effective to improve local discomfort and some distal symptoms such as depression, asthma, or metabolic disorders.

CONCLUSIONS

Although M. officinalis has rich pharmacological effects, the GI tract makes great contributions to it. The GI tract is not only an important place for absorption and metabolism but also a key site to help M. officinalis exert local and distal efficacy. Pharmacodynamical studies on the efficacies of distal tissues based on the contributions of the GI tract hold great potential for understanding the benefits of M. officinalis and providing new ideas for the treatment of important diseases.

Digestive promoting effect and mechanism of Jiao Sanxian in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Jiao Sanxian, a customary term for the three Traditional Chinese Medicines of charred hawthorn (Crataegi Fructus), charred malt (Hordei Fructus Germinatus) and Liu Shenqu (Massa Medicata Fermentata), is a classic prescription for the treatment of functional dyspepsia (FD). This prescription is called "Jiao Sanxian" in China because people believe that it is a miracle medicine for enhancing digestion and improving stagnation of digestive system. Even though Jiao Sanxian is widely used in clinical treatment, the underlying mechanism has not been clarified to date.

AIM OF THE STUDY

The present study is aimed to explore the efficacy and mechanism of Jiao Sanxian in improving the symptoms of FD in rats by using multiple pharmacological methods.

MATERIALS AND METHODS

The Sprague Dawley (SD) rats were divided into control, model, Jiao Sanxian decoction low-dosage (JSXD LD), Jiao Sanxian decoction medium-dosage (JSXD MD), and Jiao Sanxian decoction high-dosage (JSXD HD) group at random. A FD model was established with reserpine, and animals were given intragastric administration. During this period, weight and food intake of animals were recorded. Samples of rat gastric antrum, spleen, and duodenum were collected for pathological staining and immunohistochemical determination of Ghrelin protein expression after 19 days of treatment. Enzyme-linked immunosorbent assay (ELISA) was used to determine the concentration of related brain gut peptides in serum. Moreover, 16S rRNA sequencing was used to valuate the influence of intestinal flora structure of the cecal contents of experimental rats. And plasma metabolomics by Ultra Performance Liquid Chromatography coupled with Quadrupole-Time-of-Flight mass spectrometry (UPLC-Q/TOF-MS) were performed to further reveal the mechanism of action.

RESULTS

Jiao Sanxian decoction (JSXD) group with different dosage could increase body weight and food intake, improve histopathological changes, and alter disordered brain gut peptides in FD rats. 16S rRNA sequencing results described that JSXD improved the disorder of structural composition, biodiversity and function of gut microbiota in FD rats. Metabolomics illustrated 26 metabolites with JSXD treatment underwent continuous changes, which revealed JSXD might exert digestive effect by ameliorating abnormal metabolic pathways. The most relevant metabolic pathways were arachidonic acid metabolism, pyruvate metabolism, glycerophospholipid metabolism, alanine, aspartate and glutamate metabolism.

CONCLUSIONS

JSXD can improve functional dyspepsia in rats and the mechanism is related to regulate secretion of brain gut peptides, significantly improve the disorder of intestinal flora and ameliorated multi-metabolic pathways.

Gut Hormones as Potential Therapeutic Targets or Biomarkers of Response in Depression: The Case of Motilin

Recent research has identified the gut–brain axis as a key mechanistic pathway and potential therapeutic target in depression. In this paper, the potential role of gut hormones as potential treatments or predictors of response in depression is examined, with specific reference to the peptide hormone motilin. This possibility is explored through two methods: (1) a conceptual review of the possible links between motilin and depression, including evidence from animal and human research as well as clinical trials, based on a literature search of three scientific databases, and (2) an analysis of the relationship between a functional polymorphism (rs2281820) of the motilin (MLN) gene and cross-national variations in the prevalence of depression based on allele frequency data after correction for potential confounders. It was observed that (1) there are several plausible mechanisms, including interactions with diet, monoamine, and neuroendocrine pathways, to suggest that motilin may be relevant to the pathophysiology and treatment of depression, and (2) there was a significant correlation between rs2281820 allele frequencies and the prevalence of depression after correcting for multiple confounding factors. These results suggest that further evaluation of the utility of motilin and related gut peptides as markers of antidepressant response is required and that these molecular pathways represent potential future mechanisms for antidepressant drug development.

Ammonia exposure causes the imbalance of the gut-brain axis by altering gene networks associated with oxidative metabolism, inflammation and apoptosis

Ammonia is an acknowledged environment pollutant in atmosphere with irritating smell. Previous studies have shown that excessive ammonia has toxic effects on farm animals and humans. However, the detail toxicity mechanism of ammonia to pigs is still unknown so far. In order to clarify the mechanism of ammonia toxicity, we established a porcine exogenous ammonia poisoning model and assessed the effects of ammonia on the gut-brain axis by transcriptome sequencing, histological observation and chemical analysis. Our results showed that after 30 d of ammonia exposure, 578 differentially expressed genes (DEGs) and 407 DEGs were obtained in the hypothalamus and jejunum, respectively. These DEGs were enriched into Gene Ontology terms associated with inflammation, oxidative metabolism, apoptosis, and the highly expressed genes among these DEGs were verified by real-time quantitative PCR. The content of glutathione and the activities of glutathione peroxidase and superoxide dismutase were significantly decreased, while malondialdehyde content was increased after ammonia exposure. Corticotropin releasing factor, substance P, 5-hydroxytryptamine and ghrelin contents in serum elevated significantly. Furthermore, pathologic observation in the ammonia group revealed infiltration of lymphocytes in the hypothalamus and significant decrease of jejunal epithelial cells. Our results indicated that ammonia exposure mediated changes in transcriptional profiles, pathological damage, oxidative stress and brain-gut peptide of the pig jejunum and hypothalamus, and induced the imbalance of the brain-gut axis through the "oxidative stress-inflammation-apoptosis" interaction network. Our study not only provides a new perspective for the toxicity assessment of ammonia, but also enriches the toxicology mechanism of ammonia.

Pivotal Role of the Interaction Between Herbal Medicines and Gut Microbiota on Disease Treatment

With the recognition of the important role of gut microbiota in both health and disease progression, attempts to modulate its composition, as well as its co-metabolism with the organism, have attracted special attention. Abundant studies have demonstrated that dysfunction or imbalance of gut microbiota is closely related to disease progression, including endocrine diseases, neurodegenerative diseases, tumors, cardiovascular diseases, etc. Herbal medicines have been applied to prevent and treat diseases worldwide for hundreds of years. Although the underlying mechanism seems to be complex, one of the important ones is through modulating gut microbiota. In this review, co-metabolism between herbal medicines and microbiota, as well as the potential pathways are summarized from most recent published papers.

Perioperative transcutaneous electrical acupoint stimulation for improving postoperative gastrointestinal function: A randomized controlled trial

BACKGROUND

Postoperative gastrointestinal dysfunction (PGD) is one of the most common complications in patients undergoing major abdominal surgery. Acupuncture has been used widely in gastrointestinal diseases due to its effectiveness and minimally invasive nature.

OBJECTIVE

This study evaluated the efficacy of using transcutaneous electrical acupoint stimulation (TEAS) during the surgery and postoperative recovery in patients with gastric and colorectal surgery for improving postoperative gastrointestinal function.

DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS

A total of 280 patients undergoing abdominal surgery were stratified by type of surgery (i.e., gastric or colorectal surgery) and randomly allocated into the TEAS group (group T) or the sham group (group S). Patients in group T received TEAS at LI4, PC6, ST36 and ST37. Patients in group S received pseudo-TEAS at sham acupoints. The stimulation was given from 30 min before anesthesia until the end of surgery. The same treatment was performed at 9 am on the 1st, 2nd and 3rd days after surgery, until the recovery of flatus in patients.

MAIN OUTCOME MEASURES

The primary outcome was the time to the first bowel motion, as detected by auscultation. The secondary outcomes included the first flatus and ambulation time, changes of perioperative substance P (SP), incidence of PGD, postoperative pain, postoperative nausea and vomiting (PONV) and some economic indicators.

RESULTS

The time to first bowel motion, first flatus and first ambulation in group T was much shorter than that in group S (P < 0.01). In patients undergoing colorectal surgery, the concentration of SP was lower in group T than in group S on the third day after the operation (P < 0.05). The average incidence of PGD in all patients was 25%, and the frequency of PGD was significantly lower in group T than in group S (18.6% vs. 31.4%, respectively; P < 0.05). TEAS treatment (odds ratio = 0.498; 95% confidence interval: 0.232-0.786) and type of surgery were relevant factors for the development of PGD. Postoperative pain score and PONV occurrence were significantly lower in group T (P < 0.01). Postoperative hospitalization days and the resulting cost to patients were greatly reduced in the TEAS group (P < 0.01).

CONCLUSION

Perioperative TEAS was able to promote the recovery of postoperative gastrointestinal function, reduce the incidence of PGD and PONV. The concentration of SP was decreased by TEAS treatment, which indicates that the brain-gut axis may play a role in how TEAS regulates gastrointestinal function.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR1900023263.

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.