scholarly journals Hyperglycaemia-Induced Downregulation in Expression of nNOS Intramural Neurons of the Small Intestine in the Pig

2019 ◽  
Vol 20 (7) ◽  
pp. 1681 ◽  
Author(s):  
Michał Bulc ◽  
Katarzyna Palus ◽  
Michał Dąbrowski ◽  
Jarosław Całka
Keyword(s):  
Nitric Oxide ◽  
Nervous System ◽  
Small Intestine ◽  
Enteric Nervous System ◽  
Molecular Mechanisms ◽  
Muscle Relaxation ◽  
Biologically Active ◽  
Enteric Neurons ◽  
Smooth Muscle Relaxation ◽  
Gi Tract

Diabetic autonomic peripheral neuropathy (PN) involves a broad spectrum of organs. One of them is the gastrointestinal (GI) tract. The molecular mechanisms underlying the pathogenesis of digestive complications are not yet fully understood. Digestion is controlled by the central nervous system (CNS) and the enteric nervous system (ENS) within the wall of the GI tract. Enteric neurons exert regulatory effects due to the many biologically active substances secreted and released by enteric nervous system (ENS) structures. These include nitric oxide (NO), produced by the neural nitric oxide synthase enzyme (nNOS). It is a very important inhibitory factor, necessary for smooth muscle relaxation. Moreover, it was noted that nitrergic innervation can undergo adaptive changes during pathological processes. Additionally, nitrergic neurons function may be regulated through the synthesis of other active neuropeptides. Therefore, in the present study, using the immunofluorescence technique, we first examined the influence of hyperglycemia on the NOS- containing neurons in the porcine small intestine and secondly the co-localization of nNOS with vasoactive intestinal polypeptide (VIP), galanin (GAL) and substance P (SP) in all plexuses studied. Following chronic hyperglycaemia, we observed a reduction in the number of the NOS-positive neurons in all intestinal segments studied, as well as an increased in investigated substances in nNOS positive neurons. This observation confirmed that diabetic hyperglycaemia can cause changes in the neurochemical characteristics of enteric neurons, which can lead to numerous disturbances in gastrointestinal tract functions. Moreover, can be the basis of an elaboration of these peptides analogues utilized as therapeutic agents in the treatment of GI complications.

scholarly journals G protein-coupled receptor trafficking and signaling: new insights into the enteric nervous system

2019 ◽  
Vol 316 (4) ◽  
pp. G446-G452 ◽  
Author(s):  
Simona E. Carbone ◽  
Nicholas A. Veldhuis ◽  
Arisbel B. Gondin ◽  
Daniel P. Poole
Keyword(s):  
Nervous System ◽  
Enteric Nervous System ◽  
G Protein ◽  
Molecular Mechanisms ◽  
Intestinal Inflammation ◽  
Receptor Expression ◽  
Enteric Neurons ◽  
Future Research ◽  
Detailed Knowledge ◽  
G Protein Coupled

G protein-coupled receptors (GPCRs) are essential for the neurogenic control of gastrointestinal (GI) function and are important and emerging therapeutic targets in the gut. Detailed knowledge of both the distribution and functional expression of GPCRs in the enteric nervous system (ENS) is critical toward advancing our understanding of how these receptors contribute to GI function during physiological and pathophysiological states. Equally important, but less well defined, is the complex relationship between receptor expression, ligand binding, signaling, and trafficking within enteric neurons. Neuronal GPCRs are internalized following exposure to agonists and under pathological conditions, such as intestinal inflammation. However, the relationship between the intracellular distribution of GPCRs and their signaling outputs in this setting remains a “black box”. This review will briefly summarize current knowledge of agonist-evoked GPCR trafficking and location-specific signaling in the ENS and identifies key areas where future research could be focused. Greater understanding of the cellular and molecular mechanisms involved in regulating GPCR signaling in the ENS will provide new insights into GI function and may open novel avenues for therapeutic targeting of GPCRs for the treatment of digestive disorders.

V. Genes, lineages, and tissue interactions in the development of the enteric nervous system

1998 ◽  
Vol 275 (5) ◽  
pp. G869-G873
Author(s):  
Michael D. Gershon
Keyword(s):  
Nervous System ◽  
Enteric Nervous System ◽  
Neurotrophic Factor ◽  
Protein A ◽  
Growth Factor Receptor ◽  
Enteric Neurons ◽  
Gi Tract ◽  
Tissue Interactions ◽  
Multipotent Cells ◽  
V Genes

The enteric nervous system is derived from the vagal, rostral-truncal, and sacral levels of the neural crest. Because the crest-derived population that colonizes the bowel contains multipotent cells, terminal differentiation occurs in the gut and is influenced by both the enteric microenvironment and the responsivity of multiple lineages of precursors. Enteric growth factor-receptor combinations, which promote the development of enteric neurons and/or glia in most of the gastrointestinal (GI) tract, include glial cell line-derived neurotrophic factor-GFRα-1-Ret, NT-3-TrkC, a still-to-be-identified neuropoietic cytokine-ciliary neurotrophic factor receptor-α, serotonin (5-HT)-5-HT2B, and LBP110, a 110-kDa laminin-1 binding protein. A qualitatively different effect is shown by the peptide-receptor combination ET-3-ETB, which inhibits neuronal differentiation and appears to prevent the premature differentiation of enteric neurons before colonization of the GI tract has been completed (resulting in aganglionosis of the terminal colon).

scholarly journals Protein kinase G expression in the small intestine and functional importance for smooth muscle relaxation

1998 ◽  
Vol 275 (4) ◽  
pp. G629-G637 ◽  
Author(s):  
Andrea Huber ◽  
Peter Trudrung ◽  
Martin Storr ◽  
Hartmut Franck ◽  
Volker Schusdziarra ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Small Intestine ◽  
Protein Kinase ◽  
Muscle Relaxation ◽  
Inhibitory Effect ◽  
Enteric Neurons ◽  
Smooth Muscle Relaxation ◽  
No Donor ◽  
Cgmp Analog ◽  
Dependent Protein

In functional experiments, the nitric oxide (NO) donor N-morpholino- N-nitroso-aminoacetonitrile or the cGMP analog 8-(4-chlorophenylthio)-cGMP caused a concentration-dependent, tetrodotoxin-resistant relaxation of precontracted strips from rat small intestine. The inhibitory effect of both substances was completely blocked at lower concentrations and was significantly attenuated at higher concentrations by the selective cGMP-dependent protein kinase (cGK) antagonist KT-5823 (1 μM). cGK-I was identified by immunohistochemistry in circular and longitudinal muscle, lamina muscularis mucosae, and smooth muscle cells of the villi and in fibroblast-like cells of the small intestine. Additionally, there was staining of a subpopulation of myenteric and submucous plexus neurons. Double staining for neuronal NO synthase (nNOS) and cGK-I demonstrated a colocalization of these two enzymes. Western blot analysis of smooth muscle preparations and isolated nerve terminals demonstrated that these structures predominantly contain the cGK-Iβ isoenzyme, whereas the cGK-Iα expression is about threefold less. The isoform cGK-II was entirely confined to mucosal epithelial cells. These results show that cGK-I is expressed in different muscular structures of the small intestine and participates in the NO-induced relaxation of gastrointestinal smooth muscle. The presence of cGK-I in NOS-positive enteric neurons further suggests a possible neuronal action site.

scholarly journals Acute regulation of intestinal ion transport and permeability in response to luminal nutrients: the role of the enteric nervous system

2020 ◽  
Vol 318 (2) ◽  
pp. G254-G264
Author(s):  
Jean-Baptiste Cavin ◽  
Hailey Cuddihey ◽  
Wallace K. MacNaughton ◽  
Keith A. Sharkey
Keyword(s):  
Nervous System ◽  
Small Intestine ◽  
Ion Transport ◽  
Enteric Nervous System ◽  
Intestinal Permeability ◽  
Barrier Function ◽  
Enteric Neurons ◽  
Nerve Activity ◽  
Mouse Small Intestine

The small intestine regulates barrier function to absorb nutrients while avoiding the entry of potentially harmful substances or bacteria. Barrier function is dynamically regulated in part by the enteric nervous system (ENS). The role of the ENS in regulating barrier function in response to luminal nutrients is not well understood. We hypothesize that the ENS regulates intestinal permeability and ion flux in the small intestine in response to luminal nutrients. Segments of jejunum and ileum from mice were mounted in Ussing chambers. Transepithelial electrical resistance (TER), short-circuit current ( Isc), and permeability to 4-kDa FITC-dextran (FD4) were recorded after mucosal stimulation with either glucose, fructose, glutamine (10 mM), or 5% Intralipid. Mucosal lipopolysaccharide (1 mg/mL) was also studied. Enteric neurons were inhibited with tetrodotoxin (TTX; 0.5 μM) or activated with veratridine (10 μM). Enteric glia were inhibited with the connexin‐43 blocker Gap26 (20 μM). Glucose, glutamine, Intralipid, and veratridine acutely modified Isc in the jejunum and ileum, but the effect of nutrients on Isc was insensitive to TTX. TTX, Gap26, and veratridine treatment did not affect baseline TER or permeability. Intralipid acutely decreased permeability to FD4, while LPS increased it. TTX pretreatment abolished the effect of Intralipid and exacerbated the LPS‐induced increase in permeability. Luminal nutrients and enteric nerve activity both affect ion flux in the mouse small intestine acutely but independently of each other. Neither neuronal nor glial activity is required for the maintenance of baseline intestinal permeability; however, neuronal activity is essential for the acute regulation of intestinal permeability in response to luminal lipids and lipopolysaccharide. NEW & NOTEWORTHY Luminal nutrients and enteric nerve activity both affect ion transport in the mouse small intestine acutely, but independently of each other. Activation or inhibition of the enteric neurons does not affect intestinal permeability, but enteric neural activity is essential for the acute regulation of intestinal permeability in response to luminal lipids and lipopolysaccharide. The enteric nervous system regulates epithelial homeostasis in the small intestine in a time-dependent, region- and stimulus-specific manner.

scholarly journals The enteric nervous system of the human and mouse colon at a single-cell resolution

2019 ◽  
Author(s):  
Eugene Drokhlyansky ◽  
Christopher S. Smillie ◽  
Nicholas Van Wittenberghe ◽  
Maria Ericsson ◽  
Gabriel K. Griffin ◽  
...  
Keyword(s):  
Nervous System ◽  
Enteric Nervous System ◽  
Single Cell ◽  
Molecular Mechanisms ◽  
Current Model ◽  
Human Colon ◽  
Enteric Neurons ◽  
Stem Cell Maintenance ◽  
Reference Map ◽  
Human And Mouse

AbstractAs the largest branch of the autonomic nervous system, the enteric nervous system (ENS) controls the entire gastrointestinal tract, but remains incompletely characterized. Here, we develop RAISIN RNA-seq, which enables the capture of intact single nuclei along with ribosome-bound mRNA, and use it to profile the adult mouse and human colon to generate a reference map of the ENS at a single-cell resolution. This map reveals an extraordinary diversity of neuron subsets across intestinal locations, ages, and circadian phases, with conserved transcriptional programs that are shared between human and mouse. These data suggest possible revisions to the current model of peristalsis and molecular mechanisms that may allow enteric neurons to orchestrate tissue homeostasis, including immune regulation and stem cell maintenance. Human enteric neurons specifically express risk genes for neuropathic, inflammatory, and extra-intestinal diseases with concomitant gut dysmotility. Our study therefore provides a roadmap to understanding the ENS in health and disease.

Inhibitory effect of melatonin on nitric oxide synthase in rat enteric nervous system

2001 ◽  
Vol 120 (5) ◽  
pp. A176-A176
Author(s):  
P KOPPITZ ◽  
M STORR ◽  
D SAUR ◽  
M KURJAK ◽  
H ALLESCHER
Keyword(s):  
Nitric Oxide ◽  
Nervous System ◽  
Nitric Oxide Synthase ◽  
Enteric Nervous System ◽  
Inhibitory Effect ◽  
Oxide Synthase

scholarly journals The Baseline Structure of the Enteric Nervous System and Its Role in Parkinson’s Disease

Life ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 732
Author(s):  
Gianfranco Natale ◽  
Larisa Ryskalin ◽  
Gabriele Morucci ◽  
Gloria Lazzeri ◽  
Alessandro Frati ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Nervous System ◽  
Enteric Nervous System ◽  
Gi Tract ◽  
Multiple Control ◽  
Fine Control ◽  
The Central Nervous System ◽  
Degenerative Alterations ◽  
Comprehensive Classification

The gastrointestinal (GI) tract is provided with a peculiar nervous network, known as the enteric nervous system (ENS), which is dedicated to the fine control of digestive functions. This forms a complex network, which includes several types of neurons, as well as glial cells. Despite extensive studies, a comprehensive classification of these neurons is still lacking. The complexity of ENS is magnified by a multiple control of the central nervous system, and bidirectional communication between various central nervous areas and the gut occurs. This lends substance to the complexity of the microbiota–gut–brain axis, which represents the network governing homeostasis through nervous, endocrine, immune, and metabolic pathways. The present manuscript is dedicated to identifying various neuronal cytotypes belonging to ENS in baseline conditions. The second part of the study provides evidence on how these very same neurons are altered during Parkinson’s disease. In fact, although being defined as a movement disorder, Parkinson’s disease features a number of degenerative alterations, which often anticipate motor symptoms. Among these, the GI tract is often involved, and for this reason, it is important to assess its normal and pathological structure. A deeper knowledge of the ENS is expected to improve the understanding of diagnosis and treatment of Parkinson’s disease.

scholarly journals Dopamine Transporter Genetic Reduction Induces Morpho-Functional Changes in the Enteric Nervous System

Biomedicines ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 465
Author(s):  
Silvia Cerantola ◽  
Valentina Caputi ◽  
Gabriella Contarini ◽  
Maddalena Mereu ◽  
Antonella Bertazzo ◽  
...  
Keyword(s):  
Nervous System ◽  
Small Intestine ◽  
Enteric Nervous System ◽  
Dopamine Transporter ◽  
Myenteric Plexus ◽  
Receptor Activation ◽  
D1 Receptor ◽  
Functional Changes ◽  
Neurochemical Coding ◽  
The Impact

Antidopaminergic gastrointestinal prokinetics are indeed commonly used to treat gastrointestinal motility disorders, although the precise role of dopaminergic transmission in the gut is still unclear. Since dopamine transporter (DAT) is involved in several brain disorders by modulating extracellular dopamine in the central nervous system, this study evaluated the impact of DAT genetic reduction on the morpho-functional integrity of mouse small intestine enteric nervous system (ENS). In DAT heterozygous (DAT+/−) and wild-type (DAT+/+) mice (14 ± 2 weeks) alterations in small intestinal contractility were evaluated by isometrical assessment of neuromuscular responses to receptor and non-receptor-mediated stimuli. Changes in ENS integrity were studied by real-time PCR and confocal immunofluorescence microscopy in longitudinal muscle-myenteric plexus whole-mount preparations (). DAT genetic reduction resulted in a significant increase in dopamine-mediated effects, primarily via D1 receptor activation, as well as in reduced cholinergic response, sustained by tachykininergic and glutamatergic neurotransmission via NMDA receptors. These functional anomalies were associated to architectural changes in the neurochemical coding and S100β immunoreactivity in small intestine myenteric plexus. Our study provides evidence that genetic-driven DAT defective activity determines anomalies in ENS architecture and neurochemical coding together with ileal dysmotility, highlighting the involvement of dopaminergic system in gut disorders, often associated to neurological conditions.

Actions of cysteinyl leukotrienes in the enteric nervous system of guinea-pig stomach and small intestine

2003 ◽  
Vol 459 (1) ◽  
pp. 27-39 ◽  
Author(s):  
Sumei Liu ◽  
Hong-Zhen Hu ◽  
Chuanyun Gao ◽  
Na Gao ◽  
Guodu Wang ◽  
...  
Keyword(s):  
Nervous System ◽  
Small Intestine ◽  
Guinea Pig ◽  
Enteric Nervous System ◽  
Cysteinyl Leukotrienes ◽  
Guinea Pig Stomach

Transdermal Nitroglycerine in the Management of Pain Associated with Primary Dysmenorrhoea: A Multinational Pilot Study

1997 ◽  
Vol 25 (1) ◽  
pp. 41-44 ◽  
Author(s):  
O Ré ◽  
Keyword(s):  
Nitric Oxide ◽  
Pain Relief ◽  
Muscle Relaxation ◽  
Nitric Oxide Donor ◽  
Controlled Study ◽  
Smooth Muscle Relaxation ◽  
Uterine Contractility ◽  
Double Blind ◽  
Patch Application ◽  
Endogenous Nitric Oxide

Endogenous nitric oxide mediates smooth-muscle relaxation with subsequent vasodilatation in the vascular, pulmonary, gastrointestinal and genitourinary tissues. Transdermal nitroglycerine (a nitric oxide donor) has been found effective in inhibiting uterine contractility during premature labour. Sixty-five women with histories of moderate-to-severe pain associated with menses were treated with nitroglycerine patches that delivered 0.2 or 0.1 mg/h. Patches were applied as necessary during the first 3 days of the menstrual cycle for up to three consecutive cycles. Pain intensity was assessed at baseline and at 30 min and at 1, 2 and 4 h after patch application. Most patients obtained pain relief with the first dose of the first day. Pain relief was satisfactory to excellent in 90% of the patients. Headache was reported by 20% of the patients, most often in patients using two consecutive patches. A randomized, double-blind, placebo-controlled study is underway in an attempt to confirm the above findings.

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