Interstitial cells of Cajal, the Maestro in health and disease

Nobiletin, an active component of Wenyang Yiqi formula, alleviates constipation associated depression through targeting MAPT to inhibit the MAPK signaling pathway

BACKGROUND

Slow transit constipation (STC) is a common gastrointestinal disorder that is often accompanied by depression. Nobiletin is a natural compound that has been shown to have anti-inflammatory and anti-depressant effects.

PURPOSE

To study the effects of nobiletin extracted from Wenyang Yiqi Formula 19 (WYF) on STC accompanied by depression and the related mechanism in STC mouse models.

METHODS

In this study, the effects of nobiletin on STC accompanied by depression were investigated in both an STC animal model and an in vitro study. The animal model was induced by loperamide, and the in vitro study used Interstitial cells of Cajal (ICCs) isolated from STC mice. The efficacy of nobiletin was assessed by comparing various parameters, including stool particle counts, moisture content, intestinal propulsive rate, colon histopathology, microtubule-associated protein-tau (MAPT) expression in colon tissue, serum levels of TNF-α, IL-1β, IL-6, IFN-γ, and the levels of MAPK pathway-related proteins among three experimental groups.

RESULTS

Nobiletin treatment significantly improved stool particle counts, moisture content, intestinal propulsive rate, and colon histopathology in the STC animal model. Nobiletin also decreased MAPT expression in colon tissue and serum levels of TNF-α, IL-1β, IL-6, IFN-γ, and the levels of MAPK pathway-related proteins. In the in vitro study, nobiletin treatment reversed the increased cell proliferation and cell apoptosis observed in ICC isolated from the STC model.

CONCLUSION

The findings of this study indicate that nobiletin exhibits promising therapeutic potential in addressing STC accompanied by depression. This potential may be attributed to its ability to regulate the function of ICC by targeting MAPT.

Serum Metabolic Profile in Schizophrenia Patients With Antipsychotic-Induced Constipation and Its relationship With Gut Microbiome

BACKGROUND AND HYPOTHESIS

Antipsychotics (APs), the cornerstone of schizophrenia treatment, confer a relatively high risk of constipation. However, the mechanisms underpinning AP-induced constipation are poorly understood. Thus, we hypothesized that (1) schizophrenia patients with AP-induced constipation have distinct metabolic patterns; (2) there is more than one mechanism at play in producing this adverse drug effect; and (3) AP-associated changes in the gut microbiome are related to the altered metabolic profiles.

STUDY DESIGN

Eighty-eight schizophrenia patients, including 44 with constipation (C) and 44 matched patients without constipation (NC), were enrolled in this study. Constipation was diagnosed by Rome IV criteria for constipation and colonic transit time using radiopaque markers (ROMs) while severity was evaluated with the Bristol Stool Form Scale (BSS) and Constipation Assessment Scale (CAS). Fasting blood samples were drawn from all participants and were subjected to non-targeted liquid chromatography-mass spectrometry (LC-MS) metabolomic analysis.

STUDY RESULTS

Eleven metabolites were significantly altered in AP-induced constipation which primarily disturbed sphingolipid metabolism, choline metabolism, and sphingolipid signaling pathway (P value < .05, FDR < 0.05). In the C group, changes in the gut bacteria showed a certain degree of correlation with 2 of the significantly altered serum metabolites and were associated with alterations in choline metabolism.

CONCLUSIONS

Our findings indicated that there were disturbances in distinct metabolic pathways that were associated with AP-induced constipation. In addition, this study presents evidence of a link between alterations in the gut microbiome and host metabolism which provides additional mechanistic insights on AP-induced constipation.

Interstitial Cells of Cajal and Enteric Nervous System in Gastrointestinal and Neurological Pathology, Relation to Oxidative Stress

The enteric nervous system (ENS) is organized into two plexuses-submucosal and myenteric-which regulate smooth muscle contraction, secretion, and blood flow along the gastrointestinal tract under the influence of the rest of the autonomic nervous system (ANS). Interstitial cells of Cajal (ICCs) are mainly located in the submucosa between the two muscle layers and at the intramuscular level. They communicate with neurons of the enteric nerve plexuses and smooth muscle fibers and generate slow waves that contribute to the control of gastrointestinal motility. They are also involved in enteric neurotransmission and exhibit mechanoreceptor activity. A close relationship appears to exist between oxidative stress and gastrointestinal diseases, in which ICCs can play a prominent role. Thus, gastrointestinal motility disorders in patients with neurological diseases may have a common ENS and central nervous system (CNS) nexus. In fact, the deleterious effects of free radicals could affect the fine interactions between ICCs and the ENS, as well as between the ENS and the CNS. In this review, we discuss possible disturbances in enteric neurotransmission and ICC function that may cause anomalous motility in the gut.

Distributions of Platelet-Derived Growth Factor Receptor-α Positive Cells and Interstitial Cells of Cajal in the Colon of Rats with Diabetes Mellitus Type 2

Background and Objectives: Diabetic gastroenteropathy (DG) is a common complication of diabetes mellitus type 2. Interstitial cells are non-neural cells of mesenchymal origin inserted between nerve elements and smooth muscle cells, necessary for normal function and peristaltic contractions in the gastrointestinal (GI) tract. There are at least two types of interstitial cells within the GI muscle layer-interstitial cells of Cajal (ICC) and interstitial platelet-derived growth factor receptor α-positive cells (IPC). The mechanism of diabetic gastroenteropathy is unclear, and interstitial cells disorders caused by metabolic changes in diabetes mellitus (DM) could explain the symptoms of DG (slow intestinal transit, constipation, fecal incontinence). The aim of this study was to identify PDGFRα and c-kit immunoreactive cells in the colon of rats with streptozotocin-nicotinamide-induced diabetes mellitus type 2, as well as to determine their distribution in relation to smooth muscle cells and enteric nerve structures. Materials and Methods: Male Wistar rats were used, and diabetes type 2 was induced by an intraperitoneal injection of streptozotocin, immediately after intraperitoneal application of nicotinamide. The colon specimens were exposed to PDGFRα and anti-c-kit antibodies to investigate interstitial cells; enteric neurons and smooth muscle cells were immunohistochemically labeled with NF-M and desmin antibodies. Results: Significant loss of the intramuscular ICC, myenteric ICC, and loss of their connection in intramuscular linear arrays and around the ganglion of the myenteric plexus were observed with no changes in nerve fiber distribution in the colon of rats with diabetes mellitus type 2. IPC were rarely present within the colon muscle layer with densely distributed PDGFRα+ cells in the colon mucosa and submucosa of both experimental groups. In summary, a decrease in intramuscular ICC, discontinuities and breakdown of contacts between myenteric ICC without changes in IPC and nerve fibers distribution were observed in the colon of streptozotocin/nicotinamide-induced diabetes type 2 rats.

Efficacy of Bacillus coagulans BC01 on loperamide hydrochloride-induced constipation model in Kunming mice

In this study, the laxative effect of Bacillus coagulans BC01 (BC01) in mice was investigated using a functional constipation mouse model. Six-week-old male specific pathogen-free (SPF) Kunming mice were randomly divided into five groups: normal control group (saline), model group (loperamide hydrochloride), drug control group (bisacodyl), BC01 low-dose group (4.0 × 10⁸ CFU/mL) and BC01 high-dose group (4.0 × 10⁹ CFU/mL). Except for the normal group, the functional constipation model was established by administering 0.25 mL of a loperamide hydrochloride suspension (1 mg/mL) twice daily for four consecutive days by oral gavage. After modeling, the BC01 groups were administered 0.25 mL of BC01. The bisacodyl served as a control and was administered orally at a dose of 100 mg/kg, while the other groups were administered 0.25 mL of sterile saline. After 7 days of continuous administration, the experimental mice were again induced by loperamide hydrochloride. During this period, the mechanism of BC01 to improve constipation symptoms in mice was analyzed by measuring the changes in body weight, fecal water content, small intestine propulsion rate, histology of small intestinal tissue sections, fecal microbial diversity, serum indices, as well as mRNA and protein expression levels in the small intestinal tissue. BC01 was found to significantly promote the intestinal propulsion rate and increase the fecal water content in the mice. BC01 could also alleviates constipation by regulating gastrointestinal motility (substance P, motilin, endothelin-1, somatostatin, and vasoactive intestinal peptide), gene expression (c-Kit, SCF, COX-2, NF-κB, iNOS, and eNOS), intestinal inflammation (eNOS, iNOS, NF-κB), and the intestinal microbiota composition in the constipated mice. In addition, the high-dose BC01 treatment had the best preventive effect on constipation. BC01 is a probiotic strain to effectively relieve the adverse effects of constipation.

Characterization of Neurochemical Signature Alterations in the Enteric Nervous System in Autoimmune Encephalomyelitis

To date, it has remained unclear whether gastrointestinal symptoms, which are frequently observed in patients with multiple sclerosis (MS), are accompanied by pathology of the enteric nervous system (ENS). Here, the neurotransmitter signature of ENS neurons and morphological alterations of interstitial cells of Cajal (ICCs) were studied in patients with MS and mice with experimental autoimmune encephalomyelitis (EAE), which is an animal model of MS. Immunohistochemical analysis was performed on colonic whole mounts from mice with EAE and on paraffin-embedded sections of intestinal tissue from patients with MS. Antibodies against neurotransmitters or their enzymes (including vasoactive intestinal peptide (VIP), neuronal nitric oxide synthase (nNOS), and choline acetyltransferase (ChAT)) were used in conjunction with pan-neuronal markers. In addition, the presence of anoctamin 1 (ANO1)-expressing ICCs was studied. ENS changes were observed in the myenteric plexus, but they were absent in the submucosal plexus of both EAE mice and patients with MS. There was a significant decrease in the percentage of ChAT-positive neurons in EAE mice as opposed to a trend toward an increase in patients with MS. Moreover, while ANO1 expression was decreased in EAE mice, patients with MS displayed a significant increase. Although additional studies are necessary to accomplish an in-depth characterization of ENS alterations in MS, our results imply that such alterations exist and may reveal novel insights into the pathophysiology of MS.

Deregulation of Ca2+-Signaling Systems in White Adipocytes, Manifested as the Loss of Rhythmic Activity, Underlies the Development of Multiple Hormonal Resistance at Obesity and Type 2 Diabetes

Various types of cells demonstrate ubiquitous rhythmicity registered as simple and complex Ca²⁺-oscillations, spikes, waves, and triggering phenomena mediated by G-protein and tyrosine kinase coupled receptors. Phospholipase C/IP₃-receptors (PLC/IP₃R) and endothelial NO-synthase/Ryanodine receptors (NOS/RyR)–dependent Ca²⁺ signaling systems, organized as multivariate positive feedback generators (PLC-G and NOS-G), underlie this rhythmicity. Loss of rhythmicity at obesity may indicate deregulation of these signaling systems. To issue the impact of cell size, receptors’ interplay, and obesity on the regulation of PLC-G and NOS-G, we applied fluorescent microscopy, immunochemical staining, and inhibitory analysis using cultured adipocytes of epididumal white adipose tissue of mice. Acetylcholine, norepinephrine, atrial natriuretic peptide, bradykinin, cholecystokinin, angiotensin II, and insulin evoked complex [Ca²⁺]_i responses in adipocytes, implicating NOS-G or PLC-G. At low sub-threshold concentrations, acetylcholine and norepinephrine or acetylcholine and peptide hormones (in paired combinations) recruited NOS-G, based on G proteins subunits interplay and signaling amplification. Rhythmicity was cell size- dependent and disappeared in hypertrophied cells filled with lipids. Contrary to control cells, adipocytes of obese hyperglycemic and hypertensive mice, growing on glucose, did not accumulate lipids and demonstrated hormonal resistance being non responsive to any hormone applied. Preincubation of preadipocytes with palmitoyl-L-carnitine (100 nM) provided accumulation of lipids, increased expression and clustering of IP₃R and RyR proteins, and partially restored hormonal sensitivity and rhythmicity (5–15% vs. 30–80% in control cells), while adipocytes of diabetic mice were not responsive at all. Here, we presented a detailed kinetic model of NOS-G and discussed its control. Collectively, we may suggest that universal mechanisms underlie loss of rhythmicity, Ca²⁺-signaling systems deregulation, and development of general hormonal resistance to obesity.

Fibrostenotic strictures in Crohn's disease

The use of biologic agents including anti-tumor necrosis factor monoclonal antibodies followed by anti-integrins and anti-interleukins has drastically changed the treatment paradigm of Crohn’s disease (CD) by improving clinical symptoms and mucosal healing. However, up to 70% of CD patients still eventually undergo surgery mainly due to fibrostenotic strictures. There are no specific anti-fibrotic drugs yet. This review comprehensively addresses the mechanism, prediction, diagnosis and treatment of the fibrostenotic strictures in CD. We also introduce promising anti-fibrotic agents which may be available in the near future and summarize challenges in developing novel therapies to treat fibrostenotic strictures in CD.

Laxative Effects of Yangyin Tongmi Capsule on a Model of Diphenoxylate-Induced Constipation in Mice

Constipation is characterized by reduced number of bowel movements, dry stools, and difficult defecation. Yangyin Tongmi capsule (YTC), a traditional Chinese formula, is used in the treatment of constipation, while the underlying mechanisms remain unknown. Herein, this work attempted to prove the effects of YTC on constipation treatment and its possible mechanisms. KM mice were randomly divided into four groups (n = 10/group) and treated with double distilled water (Control), diphenoxylate (Model: 10 mg/kg), or diphenoxylate plus low-dose YTC (L-YTC: 0.6 g/kg) or high-dose YTC (H-YTC: 1.2 g/kg). The data indicated that YTC can significantly shorten the discharge time of the first black stool, improve intestinal propulsion rate, and increase the water content and quantity of feces in mice. ELISA suggested that YTC regulate the content of intestinal hormones and neurotransmitters, such as motilin (MTL), gastrin (GT), somatostatin (SST), substance P (SP), acetylcholine (Ach), and nitric oxide (NO). The expression levels of aquaporin 3 (AQP3) and aquaporin 8 (AQP8) in the colon were examined by immunohistochemistry. In the meantime, the expression levels of P2X2, C-kit, and stem cell factor (SCF) in the colon were examined by western blot analysis. The results of this study suggest that YTC has mitigative effects on diphenoxylate-induced constipation by regulating the content of intestinal hormones and neurotransmitters and regulating the expression of related proteins in the colon.

Anti- and pro-oxidant effects of quercetin stabilized by microencapsulation on interstitial cells of Cajal, nitrergic neurons and M2-like macrophages in the jejunum of diabetic rats

Given the well-known antioxidant and neuroprotective properties of quercetin, the aim of this work was to evaluate the effects of quercetin stabilized by microencapsulation at two doses (10 mg kg^-1 and 100 mg kg^-1) on the oxidative/antioxidant status, number and morphological features of ICC, nitrergic neurons and M2-like macrophages in jejunum of diabetic rats. The rats were randomly distributed into six groups: normoglycemic control (N), diabetic control (D) and either normoglycemic or diabetic groups treated with quercetin-loaded microcapsules at a dose of 10 mg kg^-1 (NQ10 and DQ10, respectively) or 100 mg kg^-1 (NQ100 and DQ100, respectively). After 60 days, the jejunum was collected. Whole mounts were immunostained for Ano1, nNOS and CD206, and oxidative stress levels and total antioxidant capacity of the jejunum were measured. Diabetes led to a loss of ICC and nitrergic neurons, but increased numbers of M2-like macrophages and elevated levels of oxidative stress were seen in diabetic animals. High-dose administration of quercetin (100 mg kg^-1) further aggravated the diabetic condition (DQ100) but this treatment resulted in harmful effects on healthy rats (NQ100), pointing to a pro-oxidant activity. However, low-dose administration of quercetin (10 mg kg^-1) gave rise to antioxidant and protective effects on ICC, nNOS, macrophages and oxidative/antioxidant status in DQ100, but NQ100 displayed infrequent negative outcomes in normoglycemic animals. Microencapsulation of the quercetin may become promising alternatives to reduce diabetes-induced oxidative stress but antioxidant therapies should be careful used under healthy status to avoid toxic effects.

Targeting the Enteric Nervous System to Treat Metabolic Disorders? "Enterosynes" as Therapeutic Gut Factors

The gut-brain axis is of crucial importance for controlling glucose homeostasis. Alteration of this axis promotes the type 2 diabetes (T2D) phenotype (hyperglycaemia, insulin resistance). Recently, a new concept has emerged to demonstrate the crucial role of the enteric nervous system in the control of glycaemia via the hypothalamus. In diabetic patients and mice, modification of enteric neurons activity in the proximal part of the intestine generates a duodenal hyper-contractility that generates an aberrant message from the gut to the brain. In turn, the hypothalamus sends an aberrant efferent message that provokes a state of insulin resistance, which is characteristic of a T2D state. Targeting the enteric nervous system of the duodenum is now recognized as an innovative strategy for treatment of diabetes. By acting in the intestine, bioactive gut molecules that we called "enterosynes" can modulate the function of a specific type of neurons of the enteric nervous system to decrease the contraction of intestinal smooth muscle cells. Here, we focus on the origins of enterosynes (hormones, neurotransmitters, nutrients, microbiota, and immune factors), which could be considered therapeutic factors, and we describe their modes of action on enteric neurons. This unsuspected action of enterosynes is proposed for the treatment of T2D, but it could be applied for other therapeutic solutions that implicate communication between the gut and brain.

Association of vesicoureteral reflux and gastroesophageal reflux disease in children: A population-based study

INTRODUCTION

Practitioners have anecdotally hinted at a possible association between gastroesophageal reflux disease (GERD) and vesicoureteral reflux (VUR). We sought to identify an association in diagnosis between GERD and VUR using a population-based dataset in a well-defined geographic area covered by a single-payer healthcare system.

METHODS

A retrospective review of individuals aged 0-16 years registered in the Nova Scotia Medical Service Insurance database from January 1997 to December 2012 was completed. Presence of GERD and VUR were ascertained based on billing codes. The baseline prevalence of GERD and VUR was calculated for this population for the same time period. Proportions of VUR patients with and without GERD were compared. The risk of being diagnosed with VUR in patients with GERD controlling for sex was calculated.

RESULTS

Of 404 300 patients identified, 6.6% had a diagnosis of GERD (n=27 092), 0.33% had a diagnosis of VUR (n=1348), and 0.08% were diagnosed with both (n=327). Among patients with VUR, the prevalence of GERD was 24.3% compared to 6.6% in patients without VUR (p<0.0001). Among patients with GERD, the prevalence of VUR was 1.2% compared to 0.27% in patients without (p<0.0001). The risk of being diagnosed with VUR was higher in the presence of GERD (odds ratio [OR] 4.49; 95% confidence interval [CI] 3.96-5.09; p<0.0001), irrespective of sex.

CONCLUSIONS

The odds of being diagnosed with VUR is more than 4.5 times higher in an individual with GERD. The clinical significance of this association remains to be explored.

RNA-Seq-based transcriptomic profiling of primary interstitial cells of Cajal in response to bovine viral diarrhea virus infection

Infections with bovine viral diarrhea virus (BVDV) contribute significantly to health-related economic losses in the beef and dairy industries and are widespread throughout the world. Severe acute BVDV infection is characterized by a gastrointestinal (GI) inflammatory response. The mechanism of inflammatory lesions caused by BVDV remains unknown. The interstitial cells of Cajal (ICC) network plays a pivotal role as a pacemaker in the generation of electrical slow waves for GI motility, and it is crucial for the reception of regulatory inputs from the enteric nervous system. The present study investigated whether ICC were a good model for studying GI inflammatory lesions caused by BVDV infection. Primary ICC were isolated from the duodenum of Merino sheep. The presence of BVDV was detected in ICC grown for five passages after BVDV infection, indicating that BVDV successfully replicated in ICC. After infection with BVDV strain TC, the cell proliferation proceeded slowly or declined. Morphological changes, including swelling, dissolution, and formation of vacuoles in the ICC were observed, indicating quantitative, morphological and functional changes in the cells. RNA sequencing (RNA-Seq) was performed to investigate differentially expressed genes (DEGs) in BVDV-infected ICC and explore the molecular mechanism of underlying quantitative, morphological and functional changes of ICC. Eight hundred six genes were differentially expressed after BVDV infection, of which 538 genes were upregulated and 268 genes were downregulated. Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses showed that the 806 DEGs were significantly enriched in 27 pathways, including cytokine-cytokine receptor interaction, interleukin (IL)-17 signaling and mitogen-activated protein kinase (MAPK) signaling pathways. The DEGs and raw files of high-throughput sequencing of this study were submitted to the NCBI Gene Expression Omnibus (GEO) database (accession number GSE122344). Finally, 21 DEGs were randomly selected, and the relative repression levels of these genes were tested using the quantitative real-time PCR (qRT-PCR) to validate the RNA-Seq results. The results showed that the related expression levels of 21 DEGs were similar to RNA-Seq. This study is the first to establish a new infection model for investigating GI inflammatory lesions induced by BVDV infection. RNA-Seq-based transcriptomic profiling can provide a basis for study on BVDV-associated inflammatory lesions.

Telocytes in the mouse testicular interstitium: implications of G-protein-coupled estrogen receptor (GPER) and estrogen-related receptor (ERR) in the regulation of mouse testicular interstitial cells

Telocytes (TCs), a novel type of interstitial cells, are involved in tissue homeostasis maintenance. This study aimed to investigate TC presence in the interstitium of mouse testis. Additionally, inactivation of the G-coupled membrane estrogen receptor (GPER) in the testis was performed to obtain insight into TC function, regulation, and interaction with other interstitial cells. Mice were injected with a GPER antagonist (G-15; 50 μg/kg bw), and the GPER-signaling effect on TC distribution, ultrastructure, and function, as well as the interstitial tissue interaction of GPER with estrogen-related receptors (ERRs), was examined. Microscopic observations of TC morphology were performed with the use of scanning and transmission electron microscopes. Telocyte functional markers (CD34; c-kit; platelet-derived growth factor receptors α and β, PDGFRα and β; vascular endothelial growth factor, VEGF; and vimentin) were analyzed by immunohistochemistry/immunofluorescence and Western blot. mRNA expression of CD34 as well as ERR α, β, and γ was measured by qRT-PCR. Relaxin and Ca2+ concentrations were analyzed by immunoenzymatic and colorimetric assays, respectively. For the first time, we reveal the presence of TCs in the interstitium together with the peritubular area of mouse testis. Telocytes were characterized by specific features such as a small cell body and extremely long prolongations, constituting a three-dimensional network mainly around the interstitial cells. Expression of all TC protein markers was confirmed. Based on scanning electron microscopic observation in GPER-blocked testis, groups of TCs were frequently seen. No changes were found in TC ultrastructure in GPER-blocked testis when compared to the control. However, tendency to TC number change (increase) after the blockage was observed. Concomitantly, no changes in mRNA CD34 expression and increase in ERR expression were detected in GPER-blocked testes. In addition, Ca2+ was unchanged; however, an increase in relaxin concentration was observed. Telocytes are an important component of the mouse testicular interstitium, possibly taking part in maintaining its microenvironment as well as contractile and secretory functions (via themselves or via controlling of other interstitial cells). These cells should be considered a unique and useful target cell type for the prevention and treatment of testicular interstitial tissue disorders based on estrogen-signaling disturbances.

Recently Discovered Interstitial Cell Population of Telocytes: Distinguishing Facts from Fiction Regarding Their Role in the Pathogenesis of Diverse Diseases Called "Telocytopathies"

In recent years, the interstitial cells telocytes, formerly known as interstitial Cajal-like cells, have been described in almost all organs of the human body. Although telocytes were previously thought to be localized predominantly in the organs of the digestive system, as of 2018 they have also been described in the lymphoid tissue, skin, respiratory system, urinary system, meninges and the organs of the male and female genital tracts. Since the time of eminent German pathologist Rudolf Virchow, we have known that many pathological processes originate directly from cellular changes. Even though telocytes are not widely accepted by all scientists as an individual and morphologically and functionally distinct cell population, several articles regarding telocytes have already been published in such prestigious journals as Nature and Annals of the New York Academy of Sciences. The telocyte diversity extends beyond their morphology and functions, as they have a potential role in the etiopathogenesis of different diseases. The most commonly described telocyte-associated diseases (which may be best termed "telocytopathies" in the future) are summarized in this critical review. It is difficult to imagine that a single cell population could be involved in the pathogenesis of such a wide spectrum of pathological conditions as extragastrointestinal stromal tumors ("telocytomas"), liver fibrosis, preeclampsia during pregnancy, tubal infertility, heart failure and psoriasis. In any case, future functional studies of telocytes in vivo will help to understand the mechanism by which telocytes contribute to tissue homeostasis in health and disease.

Neutrophils injure gallbladder interstitial Cajal-like cells in a guinea pig model of acute cholecystitis

Acute cholecystitis is a common disease with gallbladder dysmotility. Disease pathogenesis involves immune cell infiltration as well as changes in gallbladder interstitial Cajal-like cells (ICLCs). However, it remains unclear if or how the immune cells affect ICLC morphology, density, distribution, and function in gallbladder tissue during acute cholecystitis. In this study, we explored the acute cholecystitis-related alterations in gallbladder ICLCs in a guinea pig model, focusing on the effects of neighboring neutrophils. Adult guinea pigs were randomly divided into four groups (control, 24 hr common bile duct ligation [CBDL], 48-hr CBDL, and antipolymorphonuclear neutrophil [PMN] treated) and analyzed using methylene blue staining and immunofluorescence. Gallbladder contractility was also monitored. To culture gallbladder ICLCs, collagenase digestion was performed on tissue from 10- to 15-day-old guinea pigs. Neutrophils isolated from the peripheral blood of experimental animals 48-hr postsurgery were also cocultured with the gallbladder ICLCs. Intracellular calcium was detected with Fluo-4 AM dye. Our results showed that gallbladder ICLC density significantly declined during acute cholecystitis and was accompanied by shortening of the cellular processes and damage to their network-like structure. However, pretreatment with anti-PMN partially prevented these changes. Gallbladder contraction was also significantly decreased during acute cholecystitis, and this appeared to be mediated by the neutrophils. Moreover, ICLCs cocultured with neutrophils also had shortened and reduced processes and impaired network-like structure formation. Intracellular calcium transient was less sensitive to contraction agonists and inhibitors when cocultured with neutrophils. Taken together, neutrophils greatly affect gallbladder ICLCs and dysmotility during acute cholecystitis.

Loss of HCN2 leads to delayed gastrointestinal motility and reduced energy intake in mice

Hyperpolarization-activated Cyclic Nucleotide-gated (HCN) channels are important regulators of excitability in neural, cardiac, and other pacemaking cells, which are often altered in disease. In mice, loss of HCN2 leads to cardiac dysrhythmias, persistent spike-wave discharges similar to those seen in absence epilepsy, ataxia, tremor, reduced neuropathic and inflammatory pain, antidepressant-like behavior, infertility, and severely restricted growth. While many of these phenotypes have tissue-specific mechanisms, the cause of restricted growth in HCN2 knockout animals remains unknown. Here, we characterize a novel, 3kb insertion mutation of Hcn2 in the Tremor and Reduced Lifespan 2 (TRLS/2J) mouse that leads to complete loss of HCN2 protein, and we show that this mutation causes many phenotypes similar to other mice lacking HCN2 expression. We then demonstrate that while TRLS/2J mice have low blood glucose levels and impaired growth, dysfunction in hormonal secretion from the pancreas, pituitary, and thyroid are unlikely to lead to this phenotype. Instead, we find that homozygous TRLS/2J mice have abnormal gastrointestinal function that is characterized by less food consumption and delayed gastrointestinal transit as compared to wildtype mice. In summary, a novel mutation in HCN2 likely leads to impaired GI motility, causing the severe growth restriction seen in mice with mutations that eliminate HCN2 expression.

Naringenin induces laxative effects by upregulating the expression levels of c-Kit and SCF, as well as those of aquaporin 3 in mice with loperamide-induced constipation

Constipation is a common affliction which causes discomfort and affects the quality of life of affected individuals. Naringenin (NAR), a natural flavonoid widely found in citrus fruits and tomatoes, has been reported to exhibit various pharmacological effects, such as anti-inflammatory, anti-atherogenic, anti-mutagenic, hepatoprotective and anticancer effects. Increasing evidence has indicated that NAR has potential for use in the treatment of constipation. Thus, the aim of this study was to evaluate the laxative effects of NAR in mice with loperamide-induced (Lop-induced) constipation. The data indicated that NAR relieved Lop-induced constipation in mice based on the changes of fecal parameters (numbers, weight and water content), the intestinal charcoal transit ratio and the histological alteration. ELISA revealed that NAR regulated the production levels of gastrointestinal metabolic components, such as motilin (MTL), gastrin (Gas), endothelin (ET), substance P (SP), acetylcholinesterase (AChE) and vasoactive intestinal peptide (VIP) in serum. The expression levels of enteric nerve-related factors, glial cell line-derived neurotrophic factor (GDNF), transient receptor potential vanilloid 1 (TRPV1), nitric oxide synthase (NOS), c-Kit, stem cell factor (SCF) and aquaporin 3 (AQP3) were examined by western blot analysis and RT-PCR analysis. The results of this study suggest that NAR relieves Lop-induced constipation by increasing the levels of interstitial cells of Cajal markers (c-Kit and SCF), as well as AQP3. Thus, NAR may be effective as a candidate in patients suffering from lifestyle-induced constipation.

Spontaneous body contractions are modulated by the microbiome of Hydra

Spontaneous contractile activity, such as gut peristalsis, is ubiquitous in animals and is driven by pacemaker cells. In humans, disruption of the contraction pattern leads to gastrointestinal conditions, which are also associated with gut microbiota dysbiosis. Spontaneous contractile activity is also present in animals lacking gastrointestinal tract. Here we show that spontaneous body contractions in Hydra are modulated by symbiotic bacteria. Germ-free animals display strongly reduced and less regular contraction frequencies. These effects are partially restored by reconstituting the natural microbiota. Moreover, soluble molecule(s) produced by symbiotic bacteria may be involved in contraction frequency modulation. As the absence of bacteria does not impair the contractile ability itself, a microbial effect on the pacemakers seems plausible. Our findings indicate that the influence of bacteria on spontaneous contractile activity is present in the early-branching cnidarian hydra as well as in Bilateria, and thus suggest an evolutionary ancient origin of interaction between bacteria and metazoans, opening a window into investigating the roots of human motility disorders.

Gastric myoelectric activity during cisplatin-induced acute and delayed emesis reveals a temporal impairment of slow waves in ferrets: effects not reversed by the GLP-1 receptor antagonist, exendin (9-39)

Preclinical studies show that the glucagon-like peptide-1 (GLP-1) receptor antagonist, exendin (9-39), can reduce acute emesis induced by cisplatin. In the present study, we investigate the effect of exendin (9-39) (100 nmol/24 h, i.c.v), on cisplatin (5 mg/kg, i.p.)-induced acute and delayed emesis and changes indicative of ‘nausea’ in ferrets. Cisplatin induced 37.2 ± 2.3 and 59.0 ± 7.7 retches + vomits during the 0-24 (acute) and 24-72 h (delayed) periods, respectively. Cisplatin also increased (P<0.05) the dominant frequency of gastric myoelectric activity from 9.4 ± 0.1 to 10.4 ± 0.41 cpm and decreased the dominant power (DP) during acute emesis; there was a reduction in the % power of normogastria and an increase in the % power of tachygastria; food and water intake was reduced. DP decreased further during delayed emesis, where normogastria predominated. Advanced multifractal detrended fluctuation analysis revealed that the slow wave signal shape became more simplistic during delayed emesis. Cisplatin did not affect blood pressure (BP), but transiently increased heart rate, and decreased heart rate variability (HRV) during acute emesis; HRV spectral analysis indicated a shift to ‘sympathetic dominance’. A hyperthermic response was seen during acute emesis, but hypothermia occurred during delayed emesis and there was also a decrease in HR. Exendin (9-39) did not improve feeding and drinking but reduced cisplatin-induced acute emesis by ~59 % (P<0.05) and antagonised the hypothermic response (P<0.05); systolic, diastolic and mean arterial BP increased during the delayed phase. In conclusion, blocking GLP-1 receptors in the brain reduces cisplatin-induced acute but not delayed emesis. Restoring power and structure to slow waves may represent a novel approach to treat the side effects of chemotherapy.

Pharmacological evaluation of smooth muscle relaxant and cardiac-modulation potential of Phyla nodiflora in ex-vivo and in-vivo experiments

OBJECTIVE

To investigate the pharmacological basis of its uses of Phyla nodiflora (P. nodiflora) for the treatment of anomalies predominantly by smooth muscle containing tissues such as gastrointestinal/vascular/broncho spasm and cardiovascular modulation.

METHODS

The crude hydroalcoholic extract of P. nodiflora (Pn.Cr) and its fractions were evaluated on isolated rabbit jejunum, rat trachea, aorta and atrium. To access the contractile or relaxant effects of testing materials, the tissues were mounted in isolated organ bath and responses were recorded with transducers coupled with data acquisition system. BALB/c mice were challenged with castor oil for the assessment of in-vivo antidiarrheal activity. Normotensive rats were used for in-vivo hypotensive study.

RESULTS

Hydroalcoholic extract of Pn.Cr at variable concentrations inhibited the natural spontaneous rhythm and 80 mmol/L K⁺ mediated contractions in isolated segment of jejunum with EC₅₀ values of 3.18 and 1.91 mg/mL respectively. Verapamil, a Ca²⁺ channel blocker, demonstrated akin pattern in jejunum and therefore possibly suggesting calcium blocking activity. On isolated rat tracheal tissue, Pn.Cr showed relaxation of high-K⁺ and carbachol mediated contractions (EC₅₀ values: 1.24 and 2.42 mg/mL). Pn.Cr treatment relaxed the rat aortic ring in a cumulative doses with high-K⁺ and phenylephrine-induced contractions (EC₅₀ values 0.25 and 0.92 mg/mL). Activity based fractionation of Pn.Cr showed that dichloromethane fraction was more potent for relaxing the tissues spasm compared to aqueous fraction. In-vivo experiments, significant protection by Pn.Cr (P < 0.05) was observed in castor oil-induced diarrhea (50-500 mg/kg) whereas hypotensive effect in anesthetized rats was seen at the dose range of 1-10 mg/kg of Pn.Cr (P < 0.05).

CONCLUSION

This study suggests the blockage of calcium channel in the smooth muscles as a pharmacological application to make usage of P. nodiflora in the management of diarrhea, asthma and hypotensive effect.

Acute colonic pseudo-obstruction: A systematic review of aetiology and mechanisms

AIM

To critically review the literature addressing the definition, epidemiology, aetiology and pathophysiology of acute colonic pseudo-obstruction (ACPO).

METHODS

A systematic search was performed to identify articles investigating the aetiology and pathophysiology of ACPO. A narrative synthesis of the evidence was undertaken.

RESULTS

No consistent approach to the definition or reporting of ACPO has been developed, which has led to overlapping investigation with other conditions. A vast array of risk factors has been identified, supporting a multifactorial aetiology. The pathophysiological mechanisms remain unclear, but are likely related to altered autonomic regulation of colonic motility, in the setting of other predisposing factors.

CONCLUSION

Future research should aim to establish a clear and consistent definition of ACPO, and elucidate the pathophysiological mechanisms leading to altered colonic function. An improved understanding of the aetiology of ACPO may facilitate the development of targeted strategies for its prevention and treatment.

Stromal and immune cells in gut fibrosis: the myofibroblast and the scarface

Post-inflammatory scarring is the end-result of excessive extracellular matrix (ECM) accumulation and tissue architectural destruction. It represents a failure to effectively remodel ECM and achieve proper reinstitution and healing during chronic relapsing inflammatory processes. Scarring may affect the functionality of any organ, and in the case of inflammatory bowel disease (IBD)-associated fibrosis leads to stricture formation and often surgery to remove the affected bowel. The activated myofibroblast is the final effector cell that overproduces ECM under the influence of various mediators generated by an intense interplay of classic and non-classic immune cells. This review focuses on how proinflammatory mediators from various sources produced in different stages of intestinal inflammation can form profibrotic pathways that eventually lead to tissue scarring through sustained activation of myofibroblasts.

The Effects of Auricular Electro-Acupuncture on Ameliorating the Dysfunction of Interstitial Cells of Cajal Networks and nNOSmRNA Expression in Antrum of STZ-Induced Diabetic Rats

BACKGROUD

Interstitial cells of Cajal (ICCs) and nNOS play a crucial role in diabetic gastrointestinal dysmotility(DGD). Our previous study found that electro-acupuncture(EA) on ear point 'stomach' could repair the gastric dysrhythmias in rats induced by rectal distention(RD) after meal. However, little were known about the possible effect of auricular electro-acupuncture (AEA) on diabetic rats. Thus, we designed this study to investigate the effect of AEA on streptozotocin(STZ)-induced diabetic rats.

METHOD

Forty male Sprague_Dawley (SD) rats were injected with STZ, at the end of 8th week after injection, animals were randomly divided into four groups and received 2 weeks-treatment(10 times) respectively: control group(CON,n = 10, no stimulation), sham auricular electro-acupuncture group(SEA,n = 10, low frequency EA on earlobes), auricular eletro-acupuncture group(AEA,n = 10, low frequency EA on ear point 'stomach'), and ST-36 group(ST-36,n = 10, low frequency EA on ST-36). Gastrointestinal (GI) motility was measured by GI transit rate. ICCs(c-kit+ expression) in antrum were analyzed by Immunohistochemistry and western blotting. NO level in blood serum were detected by Griess Reagent, and nNOSmRNA expression in antrum were determined by Real-time PCR.

RESULTS

GI transit rate and ICCs(c-kit+ expression) in antrum of AEA group have the tendency to increase compared with CON group, but had no statistics difference (P>0.05). nNOSmRNA expression in antrum of AEA group was dramatically increased compared with CON group (P = 0.037).

CONCLUSIONS

Low frequency EA on ear 'stomach' point could significantly up-regulate nNOS mRNA expression and ameliorate the ICCs networks partly in gastric antrum of STZ -induced diabetic rats, which may has benefits on regulating the GI motility.

Effects of electronically stimulating Tianshu (ST 25) and Dachangshu (BL 25), Quchi (LI 11) and Shangjuxu (ST 37) on the expressions of jejunum c-kit protein and c-kit mRNA in rats with functional diarrhea

OBJECTIVE

To investigate the effects of electronically stimulating Tianshu (ST 25) and Dachangshu (BL 25), Quchi (LI 11) and Shangjuxu (ST 37) on the jejunum c-kit protein and c-kit mRNA in rats with functional diarrhea (FD).

METHODS

FD models were established through intragastric administration with folium sennae. Experimental rats were then divided into 4 groups: blank group, model group, electroacupuncture group Ⅰ [Tianshu (ST 25) and Dachangshu (BL 25) of both sides] and electroacupuncture group Ⅱ [Quchi (Li 11) and Shangjuxu (ST 37) of both sides], 10 in each. After treatment with electroacupuncture for 10 days, The expressions of jejunum c-kit protein and c-kit mRNA in each group were detected with Western blot and Real-Time quantitative real-time polymerase chain reaction (PCR).

RESULTS

The expressions of c-kit protein and c-kit mRNA in the model group increased significantly compared to those in the blank group (P < 0.01); the expressions in electroacupuncture group Ⅰsignificantly decreased compared to those in the model group (P < 0.01).

CONCLUSION

Our findings suggest that electronicall stimulating both Tianshu (ST 25) and Dachangshu (BL 25) significantly increased the expressions of jejunum c-kit protein and c-kit mRNA in FD rats, which means the treatment might have better therapeutic effects on FD.

Total Glucosides of Paeony Promote Intestinal Motility in Slow Transit Constipation Rats through Amelioration of Interstitial Cells of Cajal

Objectives

Using an atropine-diphenoxylate-induced slow transit constipation (STC) model, this study explored the effects of the total glucosides of paeony (TGP) in the treatment of STC and the possible mechanisms.

Study Design

A prospective experimental animal study.

Methods

The constipation model was set up in rats with an oral gavage of atropine-diphenoxylate and then treated with the TGP. The volume and moisture content of the faeces were observed and the intestinal kinetic power was evaluated. Meanwhile, the colorimetric method and enzyme linked immunosorbent assay (ELISA) were employed to determine the changes of nitric oxide (NO), nitric oxide synthase (NOS), vasoative intestinal peptide (VIP) and the P substance (SP) in the serum, respectively. The protein expressions of c-kit and stem cell factor (SCF) were assessed by immunohistochemical analysis and western blot, respectively, and the mRNA level of c-kit was measured by a reverse transcription polymerase chain reaction (RT-PCR).

Results

The TGP attenuated STC responses in terms of an increase in the fecal volume and moisture content, an enhancement of intestinal transit rate and the reduction of NO, NOS and VIP in the serum. In addition, the c-kit, a labeling of interstitial cells of Cajal (ICC) increased at both protein and mRNA levels. SCF, which serves as a ligand of c-kit also increased at protein level.

Conclusion

The analysis of our data indicated that the TGP could obviously attenuate STC through improving the function of ICC and blocking the inhibitory neurotransmitters such as NO, NOS and VIP.

Hirschsprung's disease - Postsurgical intestinal dysmotility

OBJECTIVE

To describe the case of an infant with Hirschsprung's disease presenting as total colonic aganglionosis, which, after surgical resection of the aganglionic segment persisted with irreversible functional intestinal obstruction; discuss the difficulties in managing this form of congenital aganglionosis and discuss a plausible pathogenetic mechanism for this case.

CASE DESCRIPTION

The diagnosis of Hirschsprung's disease presenting as total colonic aganglionosis was established in a two-month-old infant, after an episode of enterocolitis, hypovolemic shock and severe malnutrition. After colonic resection, the patient did not recover intestinal motor function that would allow enteral feeding. Postoperative examination of remnant ileum showed the presence of ganglionic plexus and a reduced number of interstitial cells of Cajal in the proximal bowel segments. At 12 months, the patient remains dependent on total parenteral nutrition.

COMMENTS

Hirschsprung's disease presenting as total colonic aganglionosis has clinical and surgical characteristics that differentiate it from the classic forms, complicating the diagnosis and the clinical and surgical management. The postoperative course may be associated with permanent morbidity due to intestinal dysmotility. The numerical reduction or alteration of neural connections in the interstitial cells of Cajal may represent a possible physiopathological basis for the condition.

Interstitial cells of Cajal are decreased in patients with gastroschisis associated intestinal dysmotility

BACKGROUND

Gastroschisis associated intestinal dysmotility (GAID) is poorly understood. Animal experiments suggest that interstitial cells of Cajal (ICC), play an important role.

METHODS

Infants with gastroschisis (GS) and GAID (time to full feed >42days) were selected. Age matched GS and control (NEC, ileal atresia, malrotation, and volvulus) samples from primary (T1) and secondary (T2) time points underwent standard histopathology and immunohistochemistry for identification of ICC, followed by evaluation of ICC numbers, distribution, morphology, relation to ganglion cells, and myenteric plexus architecture. Groups were compared using parametric and nonparametric tests.

MAIN RESULTS

Twelve patients had samples available for histopathological evaluation. GAID patients had a significantly lower total number of ICCs than controls (3 vs. 8, P<0.0029). ICC number at T1 was 2.5 vs. 6 (P=0.0629) and significantly lower at T2. (3.5 vs. 11, P=0.0124). GAID patients did not show a significant increase of ICC from T1 to T2. Controls showed a significant increase of ICC over time (6 vs. 11, P=0.0408).

CONCLUSION

Intestinal samples from infants with GAID who underwent stoma formation demonstrated fewer ICC than controls. There was no improvement or cell recovery during the study period. The ability to modulate ICC may have significant implications for the management of GAID.

Sigmoid volvulus is associated with a decrease in enteric plexuses and ganglion cells: a case-control study

PURPOSE

Although sigmoid volvulus (SV) causes acute obstruction, its pathogenesis and mechanism of torsion are unknown, and few reports have described its pathological findings. Here, we evaluated the clinicopathological characteristics of volvulus and factors contributing to volvulus of the sigmoid colon.

METHODS

We compared 14 patients with SV (10 men and 4 women; median age, 78.5 years) with 14 age- and sex-matched control patients for differences in clinical characteristics, focusing on dysmotility (enteric visceral myopathy, neuropathy, and mesenchymopathy).

RESULTS

Of the 14 SV patients, 7 had recurrent volvulus, 11 had an associated condition, and 5 required emergency surgery. Atrophy and fibrosis of the inner muscle were more prevalent in the SV than control patients (p = 0.041). Median extent (per centimeter of muscularis propria) of the myenteric plexus (12.5 versus 17.5, p < 0.001) and submucous plexus (15.0 versus 25.5, p < 0.001) was lower in the SV patients, as were the median numbers of myenteric (9.7 versus 30.4, p < 0.001) and submucous ganglion cells (10.0 versus 23.2, p < 0.001). Inflammatory neuropathy was more prevalent in the SV than control patients (p = 0.046); whereas, the prevalence of mesenchymopathy did not differ (p = 0.481).

CONCLUSIONS

A decrease in the extent of enteric plexus and ganglion cells precedes the clinical manifestation of SV. Although further elucidation is needed, this decrease may play an important role in the diagnosis of SV and in identifying the mechanism leading to torsion in SV.

Decreased expression of stem cell factor mRNA and protein in the gallbladders of guinea pigs fed on high cholesterol diet

OBJECTIVE

Sufficient evidence suggests that the c-kit protooncogene receptor and its ligand stem cell factor (scf) signal pathway play a crucial role in interstitial cells of Cajal (ICCs) development and maintenance of their phenotype. We aimed to determine the expressions of scf mRNA and scf protein in the gallbladders in guinea pigs fed on high cholesterol diet (HCD).

METHODS

The gallbladder and serum samples from 20 guinea pigs of HCD and from 20 guinea pigs of standard diet (StD) were used for this study. Serum lipid analysis was performed using standard laboratory procedure. Expression of scf mRNA was detected by reverse transcription polymerase chain reaction (RT-PCR), and expression of scf protein was detected by Western blot analysis.

RESULTS

Laboratory results showed serum total cholesterol (TC), low density lipoprotein (LDL) cholesterol , high density lipoprotein (HDL) cholesterol and triglyceride (TG) concentrations were significantly higher in the HCD group than in the StD group of guinea pigs (P < 0.001, respectively). Decreased expression of scf mRNA and protein were demonstrated in the HCD group compared with the StD group (P < 0.05 respectively).

CONCLUSION

The data indicates that the expression of scf mRNA and c-kit protein is significantly decreased in the gallbladders in guinea pigs of HCD.

Prolonged ileus in an infant presenting with primary congenital hypothyroidism

Congenital hypothyroidism (CH) is the most common endocrine disorder affecting the newborn. Universal newborn screening (NBS) has virtually eliminated the static encephalopathy and devastating neurodevelopmental syndrome known as cretinism. This report describes the presentation of an infant referred by the primary pediatrician to our hospital at 12 days of age for confirmatory testing after the NBS was consistent with CH. The infant had hypoglycemia secondary to lethargy and poor feeding and required transfer to the neonatal intensive care unit for worsening abdominal distension despite normalization of serum thyroid function tests following hormone replacement. In particular, the recalcitrant ileus and secondary bowel obstruction resulted in an additional diagnostic workup and lengthened hospital day. Our report highlights the acute gastrointestinal consequences of hypothyroidism despite evidence of effective treatment. We believe that the preclinical detection and immediate therapy for CH have lessened the prevalence of this presentation in general practice, and hence practitioners are less likely to be familiar with its natural history and management.

The effect of SCF and ouabain on small intestinal motility dysfunction induced by gastric cancer peritoneal metastasis

The interstitial cells of Cajal (ICCs) play an important role in maintaining the normal function of gastrointestinal dynamics. In our previous study, we reported that, in advanced gastric cancer, the frequency of bowel movement is always reduced, due in part to the decreased number of ICCs. To investigate the impact of ICCs in gastric cancer, we established a mouse model of gastric cancer peritoneal metastasis using SGC-7901 gastric adenocarcinoma cells and their supernatant. Then, stem cell factor (SCF) and ouabain were used as therapeutic agents to improve gut dynamics. Our data showed that, compared with the normal mice, treatment with SGC-7901 cells and their supernatant led to a significant reduction of the muscle layer thickness, a decreased number of ICCs, broadened gaps between ICCs and surrounding cells, degeneration and necrosis of smooth muscle cells (SMCs), and infiltration of inflammatory cells. In contrast to SGC-7901 cell and supernatant treatment, SCF intervention caused mild submucosal edema and mitochondrial proliferation in the ICCs and SMCs. Additionally, ouabain treatment led to inflammatory cells infiltration into the submucosa and a decreased volume of ICCs. In conclusion, our data illustrated that, under the condition of gastric cancer peritoneal metastasis, the dysfunction of intestinal peristalsis may be related to pathological changes in ICCs. Moreover, we demonstrated that SCF treatment may help to improve intestinal dynamics by regulating the number and function of ICCs.

Evaluation of the relation between interstitial cells of cajal (CD117) and serotonin receptor (5HT-3A) with postfundoplication dysphagia

OBJECTIVE

The aim of the present study is to investigate the effect of Nissen fundoplication to the pacemaker cells of an intestinal system and the serotonin receptors on an ICC membrane.

METHODS

Sixteen adult male rats were taken into study. Rats were divided in to the following two groups. Nissen fundoplication was performed to study group (Group 1) and no surgical procedures were applied to control group (group 2). The rats who were subjected to surgery and the rats without surgery were sacrificed on to postoperative 14 days. Specimens for the pathologic analysis were obtained from upper esophagus (group A) and esophagogastric junction (EGJ) (group B). Distribution of ICC and 5HT-3A were evaluated separately.

RESULTS

There was a significant difference (p=0.01, p=0.02, respectively) regarding number of cells stained with CD117 between the group 1B-2B and group 2A-2B. Also there was a significant difference between (p=0.01, p=0.01 respectively) number of cells stained with 5HT-3A in groups 1A-1B and 2A-2B. However, no correlation was detected between group 1B-2B for 5HT-3A.

CONCLUSION

A reduction in the number of ICC was observed in esophagogastric junctions of the fundoplication group but 5HT-3A distribution did not show a significant difference. A decrease in the number of ICC may be effective at postfundoplication dysphagia.

Murine genetic deficiency of neuronal nitric oxide synthase (nNOS(-/-) ) and interstitial cells of Cajal (W/W(v) ): Implications for achalasia?

BACKGROUND AND AIM

Nitric oxide (NO) is an important inhibitory mediator of esophageal function, and its lack leads to typical features of achalasia. In contrast, the role of intramuscular interstitial cells of Cajal (ICC-IM) and vasoactive intestinal peptide (VIP) in lower esophageal sphincter (LES) function is still controversial. Therefore, we examined the function and morphology of the LES in vivo in NO-deficient (nNOS(-/-) ), ICC-IM-deficient (W/W(v) )-, and wild-type (WT) mice.

METHODS

Esophageal manometry was performed with a micro-sized transducer catheter to quantify LES pressure, swallow evoked LES relaxation, and esophageal body motility. The LES morphology was examined by semiquantitative analysis of the immunoreactivity (reduction grade I-IV) of neuronal NOS (nNOS), ICC-IM, and VIP and their correlation with esophageal function.

RESULTS

nNOS(-/-) in comparison to WT mice showed a significantly higher LES mean resting pressure with an impaired swallow induced relaxation, whereas W/W(v) mice had a hypotensive LES with decreased relaxation. W/W(v) and nNOS(-/-) mice demonstrated differing degrees of tubular esophageal dysfunction. The reduced immunoreactivity of nNOS correlated with an increased LES pressure and decreased LES relaxation, respectively. Cajal-cell reduction correlated with impaired LES relaxation, whereas VIP reduction revealed no correlation with esophageal function.

CONCLUSIONS

The reduction of ICC-IM and nNOS can cause dysfunction of the LES and esophageal peristalsis, whereas VIP reduction seems to have no effect. ICC-IM and nNOS deficiency might be independent relevant causes of esophageal dysfunction similar to that seen in human achalasia.

Decreased number of interstitial cells of Cajal play an important role in the declined intestinal transit during cholesterol gallstone formation in guinea pigs fed on high cholesterol diet

To study the changes of interstitial cells of Cajal (ICCs) and expression of c-kt and scf mRNA in terminal ileum tissue during cholesterol gallstone formation in guinea pigs fed on high cholesterol diet, forty guinea pigs were divided into the gallstone group and the control group. The animals in the gallstone group were fed on a high cholesterol diet (HCD), while those in the control group fed on a standard diet (StD). The guinea pigs were sacrificed at the 8th week. The expression of c-kit and scf in terminal ileum were determined by RT-PCR and the morphological characteristics and number of ICCs were observed and calculated by using immunohistochemistry. RT-PCR showed that, compared with the control group, the c-kit and scf mRNA expression levels in the gallstone group were significantly declined. In the animal assay, the decreased number of ICCs was present obviously in the gallstone group. We concluded from the study that decreased number of ICCs, decreased expression of c-kit and scf in terminal ileum are present in guinea pigs fed on high cholesterol diet. The c-kit/scf pathway inhibition might be involved in the decline of intestinal transit function during cholesterol gallstone formation.

Incidence and survival analysis of gastrointestinal stromal tumors in shanghai: a population-based study from 2001 to 2010

Objectives. A population-based study was undertaken to investigate the epidemiological features of gastrointestinal stromal tumors (GISTs) in Shanghai, especially the incidence and the preliminary exploration of survival. Methods. A total of 1923 patients with GISTs diagnosed from 2001 to 2010 in Shanghai were reviewed. The annual incidence and overall survival of GISTs were calculated; Cox proportional hazards' regression was used to analyze several prognostic factors. Results. The average crude incidence of GISTs was 2.11 per 100,000 between 2004 and 2008, and the age-standardized incidence was 1.28 per 100,000. The incidence increased gradually from 2004 to 2008. In addition, 57% of cases had GIST in the stomach and 33% in the intestine. The 5-year overall survival of GISTs was 86.98%. The Cox regression analysis showed older age (≥65 yr versus <40 yr, HR = 5.085; (40, 65) yr versus <40 yr, HR = 1.975), male gender (HR = 1.474), and tumor locations (intestinal versus stomach, HR = 1.609) were predictors of its mortality. Conclusion. GISTs, mainly occurring in the stomach, are more common in elderly population, with an increasing incidence from 2004 to 2008. Older age, male gender, and tumor locations are risk factors for its mortality.

Control of urinary drainage and voiding

Urine differs greatly in ion and solute composition from plasma and contains harmful and noxious substances that must be stored for hours and then eliminated when it is socially convenient to do so. The urinary tract that handles this output is composed of a series of pressurizable muscular compartments separated by sphincteric structures. With neural input, these structures coordinate the delivery, collection, and, ultimately, expulsion of urine. Despite large osmotic and chemical gradients in this waste fluid, the bladder maintains a highly impermeable surface in the face of a physically demanding biomechanical environment, which mandates recurring cycles of surface area expansion and increased wall tension during filling, followed by rapid wall compression during voiding. Afferent neuronal inflow from mucosa and submucosa communicates sensory information about bladder fullness, and voiding is initiated consciously through coordinated central and spinal efferent outflow to the detrusor, trigonal internal sphincter, and external urethral sphincter after periods of relative quiescence. Provocative new findings suggest that in some cases, lower urinary tract symptoms, such as incontinence, urgency, frequency, overactivity, and pain may be viewed as a consequence of urothelial defects (either urothelial barrier breakdown or inappropriate signaling from urothelial cells to underlying sensory afferents and potentially interstitial cells). This review describes the physiologic and anatomic mechanisms by which urine is moved from the kidney to the bladder, stored, and then released. Relevant clinical examples of urinary tract dysfunction are also discussed.

Effects of lipopolysaccharide-induced inflammation on the interstitial cells of Cajal

Interstitial cells of Cajal (ICC) have recently been found to display phenotypic changes. The present study is designed to determine whether phenotypic changes occur in ICC associated with an inflammatory microenvironment and whether the ICC phenotype could be recovered after the discontinuation of inflammatory stimuli. Immunohistochemistry studies revealed that the functional ICC marker, c-kit, was markedly reduced in patients with Hirschsprung's disease (n = 34) compared with controls (n = 12), whereas another marker of ICC, CD34, was not altered significantly. Compared with the vehicle group (n = 6), intraperitoneal injection of lipopolysaccharide (LPS; 1.5 mg/kg) in mice (n = 6) significantly induced plasma tumor necrosis factor-alpha (TNF-α) levels as determined by enzyme-linked immunosorbent assay. Western blot and real-time polymerase chain reaction assessment further showed that LPS injection markedly suppressed intestinal c-kit protein and mRNA expression, which could be blocked by Toll-like receptor 4 (TLR4) deficiency (n = 6) rather than TLR2 deficiency (n = 6) and had no effects on CD34. Compared with the vehicle group (n = 6), intraperitoneal TNF-α (30 μg/kg) administration (n = 6) also significantly reduced intestinal c-kit protein and mRNA levels but not CD34 levels. However, the reduction of c-kit induced by TNF-α injection was not suppressed by TLR4 deficiency (n = 6). Intestinal c-kit protein and mRNA levels were markedly restored after the discontinuation of TNF-α administration for 7 days. Moreover, immunofluorescence analysis of primary ICC further confirmed that exposure to TNF-α for 24 h suppressed c-kit expression, which could be restored after discontinuation of TNF-α exposure. CD34 expression was not altered upon exposure to TNF-α. Thus, phenotypic changes in ICC occur in an inflammatory microenvironment in the gut and LPS, TLR4 and TNFα are crucial to this process.

Colorectal sensation and motility

PURPOSE OF REVIEW

To critically evaluate recent advances in the anatomy and physiology of colorectal motility and sensation and to discuss their potential clinical implications.

RECENT FINDINGS

Relatively noninvasive methods for the assessment of colonic transit have been developed and validated and high-resolution colonic and anorectal manometry as well as the barostat, despite their technical challenges, are beginning to show promise in clinical practice. At a more basic level, the importance of interstitial cells of Cajal as pacemakers, neuromodulators and stretch receptors has been revealed and their dysfunction associated with a number of disease states. Although the impact of a variety of biologically active agents on colonic sensorineural function in vitro has been described, the clinical implications of most of these effects remain unknown at this time. As the molecular bases of colonic motor and sensory function are identified, new disease entities are being described and novel therapeutic targets revealed. Equally important is the growing recognition of luminal factors and of the colonic microbiota, in particular, in the generation and modulation of colonic motility and sensation.

SUMMARY

The complexities of the basic physiology of colorectal motility and sensation continue to be revealed and our understanding of their regulation has progressed; clinical implications remain at a preliminary stage. Progress has been made, however, in the clinical assessment of colonic motor function.

A molecular signature of tissues with pacemaker activity in the heart and upper urinary tract involves coexpressed hyperpolarization-activated cation and T-type Ca2+ channels

Renal pacemakers set the origin and frequency of the smooth muscle contractions that propel wastes from the kidney to the bladder. Although congenital defects impairing this peristalsis are a leading cause of pediatric renal failure, the mechanisms underlying renal pacemaker activity remain unknown. Using ratiometric optical mapping and video microscopy, we discovered that hyperpolarization-activated cation (HCN) channel block with the specific anatagonist ZD7288 (30 μm; IC50) abolished the pacemaker depolarizations that initiate murine upper urinary tract peristalsis. Optical mapping and immunohistochemistry indicate that pacemaker potentials are generated by cells expressing HCN isoform-3, and that HCN3(+) cells are coupled to definitive smooth muscle via gap junctions. Furthermore, we demonstrate that HCN3(+) cells coexpress T-type Ca(2+) (TTC) channels and that TTC channel inhibition with R(-)efonidipine or NNC55-0396 decreased contractile frequency in a dose-dependent manner. Collectively, these data demonstrate that HCN3(+)/TTC(+) cells are the pacemakers that set the origin and rate of upper urinary tract peristalsis. These results reveal a conserved mechanism controlling autorhythmicity in 2 distinct muscle types, as HCN and TTC channels also mediate cardiac pacemaker activity. Moreover, these findings have translational applications, including the development of novel diagnostics to detect fetal urinary tract motility defects prior to renal damage.-Hurtado, R., Bub, G., Herzlinger, D. A molecular signature of tissues with pacemaker activity in the heart and upper urinary tract involves coexpressed hyperpolarization-activated cation and T-type Ca(2+) channels.

MR imaging in Crohn's disease: correlation of MR motility measurement with histopathology in the terminal ileum

BACKGROUND

The objective of the study was to correlate MR-detectable motility alterations of the terminal ileum with biopsy-documented active and chronic changes in Crohn's disease.

METHODS

This IRB approved retrospective analysis of 43 patients included magnetic resonance enterography (MRE) and terminal ileum biopsies (<2 weeks apart). Motility was measured at the terminal ileum using coronal 2D trueFISP pulse sequences (1.5T MRI,TR 83.8,TE1.89) and dedicated motility assessment software. Motility grading (hypermotility, normal, hypomotility, complete arrest) was agreed by two experienced readers. Motility was compared and correlated with histopathology using two-tailed Kruskal-Wallis test and paired Spearman Rank-Order Correlation tests.

KEY RESULTS

Motility abnormalities were present in 27/43 patients: nine hypomotility and 18 complete arrest. Active disease was diagnosed on 15 biopsies: eight moderate and seven severe inflammatory activity. Chronic changes were diagnosed on 17 biopsies: 13 moderate and four severe cases. In four patients with normal motility alterations on histopathology were diagnosed. Histopathology correlated with presence (P = 0.0056 for hypomotility and P = 0.0119 for complete arrest) and grade (P < 0.0001; P = 0.0004) of motility alterations. A significant difference in the motility was observed in patients with active or chronic CD compared with patients without disease (P < 0.001; P = 0.0024).

CONCLUSIONS & INFERENCES

MR-detectable motility changes of the terminal ileum correlate with histopathological findings both in active and chronic CD. Motility changes may indicate the presence pathology, but do not allow differentiation of active and chronic disease.

Expression and significance of neuroligins in myenteric cells of Cajal in Hirschsprung's disease

PURPOSE

The aim of this study was to investigate the expression and significance of neuroligins in myenteric cells of Cajal (ICC-MY) in Hirschsprung's disease (HSCR).

METHODS

Longitudinal muscle with adherent myenteric plexus (LMMP) from surgical excision waste colon of HSCR children were prepared by peeling off the mucous layer, sub-mucosal layer and circular muscle. Neuroligins, c-Kit (c-Kit-immunoreactivity representing ICC) and their relationship were assessed by double labeling immunofluorescence staining. ICC-MY were dissociated and cultured from LMMP by enzymolysis method, and were purified and analyzed using a combination of magnetic-activated cell sorting (MACS) and flow cytometry (FCM). Western-blot analysis was applied to compare and evaluate the expression levels of neuroligins in ICC-MY which were dissociated from different segments of HSCR (ganglionic colonic segment, transitional colonic segment and aganglionic colonic segment).

RESULTS

Neuroligins and c-Kit were expressed on the same cells (ICC-MY); ICC-MY were dissociated, cultured and purified. For HSCR, neuroligins were expressed significantly in ICC-MY from ganglionic colonic segments, moderately in those from transitional colonic segments and down-regulated significantly in those from aganglionic colonic segments.

CONCLUSIONS

Neuroligins were expressed in ICC-MY of human beings, and the expression varies from different segments of HSCR. This abnormal expression might play an important role in the pathogenesis of this disease through affecting the synaptic function of ICC-MY.

Loss of gastric interstitial cells of Cajal in patients with hereditary transthyretin amyloidosis

BACKGROUND

Hereditary transthyretin (TTR) amyloidosis is a systemic neuropathic disorder caused by TTR gene mutations. Gastrointestinal complications are common and the underlying mechanisms remain unclear. The interstitial cells of Cajal (ICC) function as pacemaker cells in the gastrointestinal tract and are important for gastrointestinal motility. The aim of this study was to investigate the densities of gastric ICC and nerves in patients with TTR amyloidosis compared to non-amyloidosis controls.

METHODS

Antral wall autopsy specimens from 11 Japanese ATTR V30M patients and 10 controls were analyzed with immunohistochemistry and computerized analysis. Antibodies to c-Kit and TMEM16A were used to assess ICC and an antibody to PGP 9.5 was used to assess nervous tissue. The study was approved by a Japanese ethical committee.

RESULTS

The densities of c-Kit-immunoreactive (IR) ICC were significantly lower in the circular and longitudinal muscle layers of patients compared to controls (p = 0.004 for both). Equivalent results were found for TMEM16A-IR ICC. There were no significant differences in PGP 9.5-IR cells in the circular or longitudinal muscle layers between patients and controls (p = 0.173 and 0.099, respectively).

CONCLUSIONS

A loss of gastrointestinal ICC may be an important factor for the digestive disturbances in hereditary TTR amyloidosis.

Allometric scaling relationship between frequency of intestinal contraction and body size in rodents and rabbits

This study aimed to establish an allometric scaling relationship between the frequency of intestinal contractions and body mass of different mammalian species. The frequency of intestinal contractions of rabbit, guinea pig, rat and mouse were measured using an isolated organ system. The isolated rings were prepared from proximal segments of jejunums and the frequency of contractions was recorded by an isometric force procedure. The coefficients of the obtained allometric equation were ascertained by computation of least squares after logarithmic transformation of both body mass and frequency. Significant differences (p less than 0.001) were shown in the frequency of contractions between different species. The highest frequency that corresponded to the mice was 57.7 min-1 and the 95 percent confidence interval (CI) ranged from 45.4 to 70, while rabbits showed the lowest frequency (12.71 min-1, CI: 8.6-16.8). Logarithms of frequency were statistically proportional to logarithms of body mass (r00.99; p less than 0.001). The data fitted an equation F 1/4 18:51B 0:31 and the 95 percent confidence interval of the exponent ranged from -0.30 to -0.32. The results of this study suggest that it is probably possible to extrapolate the intestinal contraction frequency of other mammalian species by the means of allometry scaling.

Advances in research on mechanism of Chinese medicine treatment of functional constipation

Functional constipation is a common disease affecting patients' health and quality of life. Chinese medicine has certain advantages in the treatment of functional constipation. In this article we review the literature and summarize the mechanisms on Chinese medicine treatment of functional constipation. Main mechanisms include lubricating the intestinal tract and increasing intestinal contents, promoting gastrointestinal motility and defecation, increasing the number of interstitial cells of Cajal in the colon and regulating the amount of intestinal neurotransmitters and hormones. We also put forward ideas and suggestions for future research.

Subclinical cecal impaction in a dog

A 7-year-old, bichon frise dog was incidentally diagnosed with cecal impaction. Typhlectomy was performed as cecal rupture and resultant septic peritonitis appeared to be imminent. Histopathological evaluation did not identify an underlying cause for impaction and cecal dysmotility was suspected. Subclinical cecal impaction has not previously been reported in dogs.