Aldioxa improves delayed gastric emptying and impaired gastric compliance, pathophysiologic mechanisms of functional dyspepsia

Targeted metabolomics revealed the mechanisms underlying the role of Liansu capsule in ameliorating functional dyspepsia

ETHNOPHARMACOLOGICAL RELEVANCE

Liansu capsule could alleviate dyspeptic symptoms; however, the mechanisms underlying its role in treating functional dyspepsia (FD) remain unclear.

AIM OF THE STUDY

To elucidate the mechanism underlying the efficacy of Liansu capsule in alleviating FD symptoms.

MATERIALS AND METHODS

Thirty-six male mice were randomly divided into the following six groups: control, model, low-strength Liansu, moderate-strength Liansu, high-strength Liansu, and domperidone groups. Small intestine propulsion rate, gastric residual rate and histopathological analysis were performed to evaluate efficacy of Liansu capsule. Levels of interleukin-1β, interleukin-6, tumor necrosis factor α, phosphorylation of p65, ghrelin and gastrin were verified by real-time quantitative polymerase chain reaction and immunofluorescence assays. Targeted metabolomic analyses, western blotting and immunofluorescence assays were used to explore the mechanism of Liansu capsule in ameliorating FD.

RESULTS

The Liansu capsule significantly ameliorated the symptoms of FD, and markedly increased the levels of ghrelin and gastrin. Moreover, Liansu capsule significantly downregulated the levels of the proinflammatory cytokine interleukin-1β, interleukin-6, tumor necrosis factor α, and inhibited the phosphorylation of p65. Targeted metabolomic analyses showed that Liansu capsule significantly reduced the levels of deoxycholic acid and hyodeoxycholic acid, which were significantly elevated in the model group. Furthermore, these results showed that deoxycholic acid and hyodeoxycholic acid markedly promoted the levels of Takeda G-protein-coupled receptor 5 (TGR5), phosphorylated signal transducer and activator of transcription 3 (STAT3), and Kruppel-like factor 5 (KLF5) in vitro. whereas, Liansu capsule significantly reduced the levels of TGR5, phosphorylated STAT3, and KLF5.

CONCLUSION

Our findings indicated that Liansu capsule improved FD by regulating the deoxycholic acid/hyodeoxycholic acid-TGR5-STAT3-KLF5 axis. The findings reveal a novel mechanism underlying the role of Liansu capsule, which may be a promising therapeutic strategy for FD.

The efficacy of cognitive behavior stress management on functional dyspepsia: A protocol for systematic review and meta-analysis

BACKGROUND

Functional dyspepsia and digestive disorders are common, debilitating and costly. Little information is available about the role of stress management in terms of cognitive-behavioral treatment of dyspepsia. We performed a protocol for systematic review and meta-analysis to evaluate the effectiveness of cognitive behavior stress management for the treatment of functional dyspepsia.

METHODS

A comprehensive search of several databases from 1966 to March 2022 will be conducted. The databases include Ovid Medline In-Process & Other Non-Indexed Citations, Ovid MEDLINE, Ovid EMBASE, Ovid PsycINFO, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, and Scopus. The primary outcome for this study was the rate of successful treatment (presence of no more than mild pain or discomfort after treatment). The secondary outcomes were improvement of dyspepsia at short-term (<1 year) and long-term (≥1 year) follow up, improvement in quality of life, and development of treatment-related adverse events. The risk of bias in each included study will be assessed utilizing the Cochrane Collaboration's risk of bias tool. The Review Manager 5.3 (Cochrane Collaboration, Oxford, UK) will be used to analyze the data.

RESULTS

We will synthesize the current studies to evaluate the effectiveness and safety of cognitive behavior stress management on functional dyspepsia.

CONCLUSION

The result of this review will provide more reliable references to help clinicians make decisions when dealing with functional dyspepsia.

Gastric accommodation: Physiology, diagnostic modalities, clinical relevance, and therapies

BACKGROUND

Gastric accommodation is an essential gastric motor function which occurs following ingestion of a meal. Impaired gastric fundic accommodation (IFA) is associated with dyspeptic symptoms. Gastric accommodation is mediated by the vagal pathway with several important physiologic factors such as duodenal nutrient feedback playing a significant role. IFA has been described as a pathophysiologic factor in several gastrointestinal disorders including functional dyspepsia, diabetic gastropathy, post-Nissen fundoplication, postsurgical gastrectomy, and rumination syndrome. Modalities for gastric accommodation assessment include gastric barostat, intragastric meal distribution via scintigraphy, drinking tests (eg, water load), SPECT, MRI, 2D and 3D ultrasound, and intragastric high-resolution manometry. Several treatment options including sumatriptan, buspirone, tandospirone, ondansetron, and acotiamide may improve symptoms by increasing post-meal gastric volume.

PURPOSE

Our aim is to provide an overview of the physiology, diagnostic modalities, and therapies for IFA. A literature search was conducted on PubMed, Google Scholar, and other sources to identify relevant studies available until December 2020. Gastric accommodation is an important gastric motor function which if impaired, is associated with several upper gastrointestinal disorders. There are an increasing number of gastric accommodation testing modalities; however, each has facets which warrant consideration. Evidence regarding potentially effective therapies for IFA is growing.

Carnosine and Lung Disease

Carnosine (β-alanyl-L-histidine) is a small dipeptide with numerous activities, including antioxidant effects, metal ion chelation, proton buffering capacity, and inhibitory effects on protein carbonylation and glycation. Carnosine has been mostly studied in organs where it is abundant, including skeletal muscle, cerebral cortex, kidney, spleen, and plasma. Recently, the effect of supplementation with carnosine has been studied in organs with low levels of carnosine, such as the lung, in animal models of influenza virus or lipopolysaccharide-induced acute lung injury and pulmonary fibrosis. Among the known protective effects of carnosine, its antioxidant effect has attracted increasing attention for potential use in treating lung disease. In this review, we describe the in vitro and in vivo biological and physiological actions of carnosine. We also report our recent study and discuss the roles of carnosine or its related compounds in organs where carnosine is present in only small amounts (especially the lung) and its protective mechanisms.

Protective effect of polaprezinc on cadmium-induced injury of lung epithelium

Cadmium is a toxic metal contained in food, water and the atmosphere, and exposure to cadmium can cause respiratory diseases in humans. Various health problems caused by cadmium result from oxidative stress-dependent cellular injury. Metallothioneins are intracellular, cysteine-rich, metal-binding proteins that have a detoxifying action on heavy metals such as cadmium in various organs. In addition, expression of metallothioneins is induced by metals with low biological toxicity, such as zinc. Therefore, in this study we examined whether polaprezinc, a chelate compound consisting of carnosine and zinc, can suppress cadmium-induced lung epithelial cell death. We found that cell viability markers (intracellular ATP levels and mitochondrial activity) and cytotoxicity (lactate dehydrogenase release) were decreased and increased, respectively by cadmium treatment; however, polaprezinc significantly reversed these changes. Moreover, cadmium-dependent endoplasmic reticulum stress responses were suppressed by polaprezinc treatment. We then examined the protective mechanisms of polaprezinc, focusing on oxidative stress. Cadmium induced the production of reactive oxygen species (ROS) in A549 cells in a dose-dependent manner and polaprezinc significantly suppressed this cadmium-induced ROS production. Finally, we examined whether polaprezinc exerts an antioxidative action by inducing metallothioneins. We found that polaprezinc dose-dependently induced metallothioneins using real-time RT-PCR, ELISA, and western blotting analyses. These results indicate that polaprezinc can suppress cadmium-induced lung epithelial cell death and oxidative stress by inducing metallothioneins. We therefore suggest that polaprezinc may have therapeutic effects against respiratory diseases, such as chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis.

Idebenone has preventative and therapeutic effects on pulmonary fibrosis via preferential suppression of fibroblast activity

Alveolar epithelial injury induced by reactive oxygen species (ROS) and abnormal collagen production by activated fibroblasts (myofibroblasts) is involved in the onset and exacerbation of idiopathic pulmonary fibrosis (IPF). Compared with alveolar epithelial cells, lung fibroblasts, especially myofibroblasts, exhibit an apoptosis-resistance phenotype (apoptosis paradox) that appears to be involved in IPF pathogenesis. Thus, we screened for chemicals eliciting preferential cytotoxicity of LL29 cells (lung fibroblasts from an IPF patient) compared with A549 cells (human lung alveolar epithelial cell line) from medicines already in clinical use. We identified idebenone, a synthetic analogue of coenzyme Q10 (CoQ₁₀, an antioxidant) that has been used clinically as a brain metabolic stimulant. Idebenone induced cell growth inhibition and cell death in LL29 cells at a lower concentration than in A549 cells, a feature that was not observed for other antioxidant molecules (such as CoQ₁₀) and two IPF drugs (pirfenidone and nintedanib). Administration of idebenone prevented bleomycin-induced pulmonary fibrosis and increased pulmonary ROS levels. Importantly, idebenone also improved pulmonary fibrosis and lung function when administered after the development of fibrosis, whereas administration of CoQ₁₀ similarly prevented bleomycin-induced pulmonary fibrosis, but had no effect after its development. Administration of idebenone, but not CoQ₁₀, suppressed bleomycin-induced increases in lung myofibroblasts. In vitro, treatment of LL29 cells with idebenone, but not CoQ₁₀, suppressed TGF-β–induced collagen production. These results suggest that in addition to antioxidant activity, idebenone exerts inhibitory activity on the function of lung fibroblasts, with the former activity being preventative and the latter therapeutic for bleomycin-induced fibrosis. Thus, we propose that idebenone may be more therapeutically beneficial for IPF patients than current treatments.

Gastric Emptying of Low- and High-Caloric Liquid Meals Measured Using Ultrasonography in Healthy Volunteers

Purpose

Delayed gastric emptying is present in patients with functional dyspepsia (FD), diabetes mellitus, and neurological diseases. Diet may affect gastric emptying symptoms in patients with FD. We sought to determine the extent to which gastric emptying and symptoms of dyspepsia are influenced by caloric content in healthy subjects using ultrasonography.

Materials and Methods

32 healthy volunteers were given 2 meals with different caloric content in random order. Gastric emptying was determined using ultrasonography to measure antral area when fasting, and postprandially at intervals of 0, 10, 20, and 30 min. Dyspeptic symptoms including discomfort, nausea, and fullness were graded.

Results

The antral area following a high-caloric meal compared to a low-caloric meal was significantly increased at 0, 10, 20, and 30 min (P=0.0203,<0.0001<0.0001,<0.0001, respectively), as was the median fullness (P<0.0048, 0.0001, 0.0009, 0.0001, respectively) measured at the same time points. There was a weak correlation (r2=0.1, P<0.0001) between the antral area and subjective fullness. No differences between gastric emptying in males and females were found.

Conclusion

The caloric content of a meal influences gastric emptying. Using ultrasonography to measure the antral area helps us to assess gastric emptying and therefore to assess patients with functional dyspepsia.

Choosing an Animal Model for the Study of Functional Dyspepsia

Functional dyspepsia (FD) is a common functional gastrointestinal disorder with pain or discomfort in the upper abdomen as the main characteristic. The prevalence of FD worldwide varies between 5% and 11%. This condition adversely affects attendance and productivity in the workplace. Emerging evidence is beginning to unravel the pathophysiologies of FD, and new data on treatment are helping to guide evidence-based practice. In order to better understand the pathophysiologies of FD and explore better treatment options, various kinds of animal models of FD have been developed. However, it is unclear which of these models most closely mimic the human disease. This review provides a comprehensive overview of the currently available animal models of FD in relationship to the clinical features of the disease. The rationales, methods, merits, and disadvantages for modelling specific symptoms of FD are discussed in detail.

Comparative Researches of Semen Arecae and Charred Semen Arecae on Gastrointestinal Motility, Motilin, Substance P, and CCK in Chronically Stressed Rats

Aims

To compare the effects of Semen Arecae (SA) and Charred Semen Arecae (CSA) on gastrointestinal motility, motilin, substance P (SP), and cholecystokinin (CCK) in chronically stressed rats.

Methods

Rats were randomly divided into control group and stress group. Rats in stress group were randomly exposed to a variety of unpredictable stimulations for 21 days. Then, the rats were treated orally with distilled water, SA, CSA, and mosapride for 7 days. Gastric residue rate and intestinal propulsion rate were evaluated. Serum levels of motilin and SP were measured by enzyme-linked immunosorbent assay (ELISA). CCK mRNA was quantified by using quantitative real-time PCR (qRT-PCR).

Results

Both SA and CSA improved the intestinal propulsion and reduced the gastric residue in chronically stressed rats. Furthermore, the serum levels of motilin and SP were significantly higher and the CCK mRNA expressions in intestine and hypothalamus were downregulated in SA and CSA groups. Furthermore, it was found that CSA is more effective.

Conclusion

Both SA and CSA enhanced gastrointestinal motility and increased serum levels of motilin and SP in chronically stressed rats via downregulating CCK mRNA expressions in intestine and hypothalamus. Importantly, CSA possessed more effective promoting effects.

Association between metabolic profile and microbiomic changes in rats with functional dyspepsia

Functional dyspepsia (FD) is one of the most prevalent functional gastrointestinal disorders (FGIDs). Accumulated evidence has shown that FD is a metabolic disease that might relate to gut microbiota, but the relationship between microbiome and the host metabolic changes is still uncertain. To clarify the host–microbiota co-metabolism disorders related to FD, an integrated approach combining ¹H NMR-based metabolomics profiles, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and 16S rRNA gene sequencing was used to investigate the relationship among FD, metabolism of gut microbiota and the host. 34 differential urinary metabolites and 19 differential fecal metabolites, which affected the metabolism of energy, amino acids, nucleotides and short chain fatty acids (SCFAs), were found to have associated with FD. Based on the receiver operating characteristic (ROC) analysis, 10 biomarkers were screened out as diagnostic markers of FD. Meanwhile, the concentrations of Flintibacter, Parasutterella, Eubacterium and Bacteroides significantly increased in the FD group, whereas Eisenbergiella, Butyrivibrio, Intestinimonas, Saccharofermentans, Acetivibrio, Lachnoanaerobaculum and Herbinix significantly decreased. Furthermore, the above altered microbiota revealed a strong correlation with the intermediate products of the tricarboxylic acid (TCA) cycle, amino acids and SCFAs. In our study, it suggested that the energy metabolism was mainly disturbed in FD rats. Our findings also demonstrated that FD might be the result of gut microbiota and metabolism disorders, which was potentially valuable to enrich our understanding of the pathogenesis of FD.

Functional dyspepsia (FD) is one of the most prevalent functional gastrointestinal disorders (FGIDs). The aim of our study was to evaluate the effects of FD on the microbiota and its metabolic profiles in feces and urine.

Weikangning therapy in functional dyspepsia and the protective role of Nrf2

Functional dyspepsia (FD) is a non-organic gastrointestinal disorder that has a marked negative impact on quality of life. Compared with conventional pharmacological therapies, the traditional Chinese medicine weikangning (WKN) is a safe and effective treatment for FD. The present study aimed to determine the molecular mechanisms underlying the efficacy of WKN. The effect of different concentrations of WKN on the proliferation of the human gastric mucosal epithelial cell line GES-1 was assessed. The optimal WKN concentration to promote cell proliferation was determined, and this concentration was used to examine the effect of WKN compared with a domperidone-treated positive control group on the antioxidant capacity of GES-1 cells. The effect of WKN treatment on the growth and antioxidant activity of GES-1 cells was also assessed following nuclear factor erythroid 2 like 2 (Nrf2) knockdown. The optimal WKN dose for promoting cell growth was determined to be 0.025 mg/ml; at this concentration the expression of the antioxidant proteins glutathione S-transferase P and superoxide dismutase 2 (SOD2) were significantly elevated (P<0.0001). Furthermore, the amount of reduced glutathione and activity of SOD2 were significantly increased (P<0.0001 and P<0.01, respectively), and malondialdehyde content was significantly decreased, compared with the controls (P<0.001). With WKN treatment, the transcription of Nrf2 and its downstream genes were significantly upregulated (P<0.01), and the level and nuclear distribution of Nrf2 protein was also markedly increased. Following Nrf2 silencing, the protective antioxidant effects of WKN treatment were impaired and GES-1 cell proliferation decreased. The results of the present study suggest that the efficacy of WKN in protecting gastric mucosal epithelial cells in FD is antioxidant-dependent and mediated by Nrf2 activation.

Protective and therapeutic effect of felodipine against bleomycin-induced pulmonary fibrosis in mice

Idiopathic pulmonary fibrosis (IPF) involves alveolar epithelial injury and abnormal collagen production caused by activated fibroblasts; transforming growth factor (TGF)-β1 is implicated in this activation. In this study, we screened for chemicals capable of inhibiting TGF-β1-induced collagen production in cultured fibroblasts from medicines already in clinical use. We selected felodipine based on its extent of collagen production inhibition, clinical safety profile, and other pharmacological activity. Felodipine is a dihydropyridine Ca²⁺ channel blocker that has been used clinically to treat patients with high blood pressure. Felodipine suppressed collagen production within LL29 cells in the presence of TGF-β1, but not in its absence. Intratracheal administration of felodipine prevented bleomycin-induced pulmonary fibrosis, alteration of lung mechanics and respiratory dysfunction. Felodipine also improved pulmonary fibrosis, as well as lung and respiratory function when administered after fibrosis development. Furthermore, administration of felodipine suppressed a bleomycin-induced increase in activated fibroblasts in the lung. We also found other dihydropyridine Ca²⁺ channel blockers (nifedipine and benidipine) inhibited collagen production in vitro and partially prevented bleomycin-induced pulmonary fibrosis, alteration of lung mechanics and respiratory dysfunction in vivo. We propose that these Ca²⁺ channel blockers may be therapeutically beneficial for IPF patients.

Acotiamide improves stress-induced impaired gastric accommodation

BACKGROUND

Gastric accommodation is a reflex reaction related to gastric reservoir function. Psychological stress, such as anxiety, inhibits gastric accommodation in humans. Acotiamide enhances the effect of acetylcholine in the enteric nervous system, enhances gastric contractility, and accelerates delayed gastric emptying. However, the effect of acotiamide on stress-induced impaired gastric accommodation remains unclear. Therefore, we examined the effect of acotiamide on gastric accommodation and stress-induced impaired gastric accommodation using a conscious guinea pig model.

METHODS

A polyethylene bag was inserted through the distal region of the gastric body into the proximal stomach of 5-week-old male Hartley guinea pigs. Gastric accommodation was evaluated by measuring the intrabag pressure in the proximal stomach after oral administration of a liquid meal. In the stress model, animals were subjected to water-avoidance stress. Acotiamide (Z-338) or nizatidine was administered subcutaneously. Fecal output was determined as the number of fecal pellets.

KEY RESULTS

Administration of the liquid meal significantly decreased intrabag pressure, indicating induction of gastric accommodation. Acotiamide treatment prolonged liquid meal-induced gastric accommodation and significantly increased the number of fecal pellets compared to controls. Water-avoidance stress significantly inhibited liquid meal-induced gastric accommodation. Pretreatment with acotiamide significantly improved stress-induced impaired gastric accommodation. The number of fecal pellets in the acotiamide group increased significantly compared to controls. Acotiamide, but not nizatidine, significantly decreased gastric emptying.

CONCLUSIONS & INFERENCES

Acotiamide prolongs gastric accommodation and improves stress-induced impaired gastric accommodation, indicating a potential role for acotiamide in the treatment of functional dyspepsia through its effects on gastric accommodation reactions.

NMR-based metabonomics and correlation analysis reveal potential biomarkers associated with chronic atrophic gastritis

Chronic atrophic gastritis (CAG) is one of the most important pre-cancerous states with a high prevalence. Exploring of the underlying mechanism and potential biomarkers is of significant importance for CAG. In the present work, ¹H NMR-based metabonomics with correlative analysis was performed to analyze the metabolic features of CAG. 19 plasma metabolites and 18 urine metabolites were enrolled to construct the circulatory and excretory metabolome of CAG, which was in response to alterations of energy metabolism, inflammation, immune dysfunction, as well as oxidative stress. 7 plasma biomarkers and 7 urine biomarkers were screened to elucidate the pathogenesis of CAG based on the further correlation analysis with biochemical indexes. Finally, 3 plasma biomarkers (arginine, succinate and 3-hydroxybutyrate) and 2 urine biomarkers (α-ketoglutarate and valine) highlighted the potential to indicate risks of CAG in virtue of correlation with pepsin activity and ROC analysis. Here, our results paved a way for elucidating the underlying mechanisms in the development of CAG, and provided new avenues for the diagnosis of CAG and presented potential drug targets for treatment of CAG.

Anethole restores delayed gastric emptying and impaired gastric accommodation in rodents

Functional dyspepsia (FD), a functional gastrointestinal disorder, is characterized by persistent or recurrent postprandial upper abdominal discomfort and epigastric pain. The high prevalence of FD and associated healthcare costs suggests that treatment of this condition by methods other than prescribed medicines, such as natural products, could be beneficial. Delayed gastric emptying and impaired gastric accommodation play important roles in the development of FD. Anethole (1-methoxy-4-((E)-propenyl)-benzene), a major component of essential fennel oil, has been used as a flavoring, in alcoholic beverage production and in pharmaceutical formulations for many years. In this study, we examined the effects of anethole on delayed gastric emptying and impaired gastric accommodation in rodents. Oral administration of anethole improved clonidine-induced delayed gastric emptying but did not affect normal gastric emptying in mice. Fennel oil and Anchu-san (a Japanese herbal medicine containing anethole) also restored delayed gastric emptying. Furthermore, oral administration of anethole stimulated gastric accommodation in rats. These results suggest that anethole could be beneficial for the treatment of FD.