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Cullum SA, Platt S, Dale N, Isaac OC, Wragg ES, Soave M, Veprintsev DB, Woolard J, Kilpatrick LE, Hill SJ. Mechano-sensitivity of β2-adrenoceptors enhances constitutive activation of cAMP generation that is inhibited by inverse agonists. Commun Biol 2024; 7:417. [PMID: 38580813 PMCID: PMC10997663 DOI: 10.1038/s42003-024-06128-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 03/29/2024] [Indexed: 04/07/2024] Open
Abstract
The concept of agonist-independent signalling that can be attenuated by inverse agonists is a fundamental element of the cubic ternary complex model of G protein-coupled receptor (GPCR) activation. This model shows how a GPCR can exist in two conformational states in the absence of ligands; an inactive R state and an active R* state that differ in their affinities for agonists, inverse agonists, and G-protein alpha subunits. The proportion of R* receptors that exist in the absence of agonists determines the level of constitutive receptor activity. In this study we demonstrate that mechanical stimulation can induce β2-adrenoceptor agonist-independent Gs-mediated cAMP signalling that is sensitive to inhibition by inverse agonists such as ICI-118551 and propranolol. The size of the mechano-sensitive response is dependent on the cell surface receptor expression level in HEK293G cells, is still observed in a ligand-binding deficient D113A mutant β2-adrenoceptor and can be attenuated by site-directed mutagenesis of the extracellular N-glycosylation sites on the N-terminus and second extracellular loop of the β2-adrenoceptor. Similar mechano-sensitive agonist-independent responses are observed in HEK293G cells overexpressing the A2A-adenosine receptor. These data provide new insights into how agonist-independent constitutive receptor activity can be enhanced by mechanical stimulation and regulated by inverse agonists.
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Affiliation(s)
- Sean A Cullum
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Simon Platt
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Natasha Dale
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Oliver C Isaac
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Edward S Wragg
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Mark Soave
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Dmitry B Veprintsev
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Jeanette Woolard
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Laura E Kilpatrick
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
- Division of Bimolecular Science and Medicinal Chemistry, School of Pharmacy, Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Stephen J Hill
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK.
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK.
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2
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Fountzilas C, Velasco SA, Bshara W, LeVea CM, Gupta M, Ji W, George A, Attwood K, Iyer RV. Evaluation of the serotonin pathway as a biomarker in cholangiocarcinoma. J Gastrointest Oncol 2023; 14:2192-2201. [PMID: 37969829 PMCID: PMC10643599 DOI: 10.21037/jgo-23-115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Accepted: 07/21/2023] [Indexed: 11/17/2023] Open
Abstract
Background Cholangiocarcinomas (CCAs) are rare and aggressive malignant tumors of the biliary tract. Serotonin (5HT) has tumor-promoting effects in CCA while inhibition of 5HT synthesis can decrease tumor growth. Methods In this retrospective study, we evaluated the expression of 5HT and tryptophane hydroxylase-1 (TPH-1) in tumor specimens from patients treated with cisplatin plus gemcitabine (CisGem). We included consecutive patients ≥18 years, with locally advanced unresectable, recurrent, or metastatic CCA who were treated with CisGem and had available archival tumor tissue for immunohistochemistry. Formalin-fixed paraffin (FFPE) sections were stained for 5HT and TPH-1. Specimens were evaluated for neuroendocrine features and tumor-infiltrating lymphocytes (TILs). Serum 5HT was measured. Results We identified 23 patients fulfilling the inclusion criteria. 5HT expression was absent in almost all tumors examined. TPH-1 expression was neither associated with stage or primary tumor location nor predictive of response to CisGem. There was a trend for improved overall survival (OS) in patients whose tumors had high TPH-1 expression. The examined tumor specimens had no neuroendocrine features. Most sections had no TILs. There was a trend for worse OS in patients with high serum 5HT concentration. Conclusions Tumor TPH-1 expression was not predictive of response to treatment. There was a trend for improved long-term outcomes in patients with high tumor TPH expression and lower serum 5HT concentration.
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Affiliation(s)
- Christos Fountzilas
- Department of Medicine, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | | | - Wiam Bshara
- Pathology Network Shared Resource, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Charles M. LeVea
- Department of Pathology, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Medhavi Gupta
- Program in Women’s Oncology, Women & Infants Hospital, Brown University, Providence, RI, USA
| | - Wenyan Ji
- Center for Biostatistics and Health Data Science, Virginia Tech, Roanoke, VA, USA
| | - Anthony George
- Department of Biostatistics and Bioinformatics, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Kristopher Attwood
- Department of Biostatistics and Bioinformatics, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Renuka V. Iyer
- Department of Medicine, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
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3
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Swain SM, Liddle RA. Mechanosensing Piezo channels in gastrointestinal disorders. J Clin Invest 2023; 133:e171955. [PMID: 37781915 PMCID: PMC10541197 DOI: 10.1172/jci171955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/03/2023] Open
Abstract
All cells in the body are exposed to physical force in the form of tension, compression, gravity, shear stress, or pressure. Cells convert these mechanical cues into intracellular biochemical signals; this process is an inherent property of all cells and is essential for numerous cellular functions. A cell's ability to respond to force largely depends on the array of mechanical ion channels expressed on the cell surface. Altered mechanosensing impairs conscious senses, such as touch and hearing, and unconscious senses, like blood pressure regulation and gastrointestinal (GI) activity. The GI tract's ability to sense pressure changes and mechanical force is essential for regulating motility, but it also underlies pain originating in the GI tract. Recent identification of the mechanically activated ion channels Piezo1 and Piezo2 in the gut and the effects of abnormal ion channel regulation on cellular function indicate that these channels may play a pathogenic role in disease. Here, we discuss our current understanding of mechanically activated Piezo channels in the pathogenesis of pancreatic and GI diseases, including pancreatitis, diabetes mellitus, irritable bowel syndrome, GI tumors, and inflammatory bowel disease. We also describe how Piezo channels could be important targets for treating GI diseases.
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4
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Asseri AH, Bakhsh T, Abuzahrah SS, Ali S, Rather IA. The gut dysbiosis-cancer axis: illuminating novel insights and implications for clinical practice. Front Pharmacol 2023; 14:1208044. [PMID: 37361202 PMCID: PMC10288883 DOI: 10.3389/fphar.2023.1208044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 05/31/2023] [Indexed: 06/28/2023] Open
Abstract
The human intestinal microbiota, also known as the gut microbiota, comprises more than 100 trillion organisms, mainly bacteria. This number exceeds the host body cells by a factor of ten. The gastrointestinal tract, which houses 60%-80% of the host's immune cells, is one of the largest immune organs. It maintains systemic immune homeostasis in the face of constant bacterial challenges. The gut microbiota has evolved with the host, and its symbiotic state with the host's gut epithelium is a testament to this co-evolution. However, certain microbial subpopulations may expand during pathological interventions, disrupting the delicate species-level microbial equilibrium and triggering inflammation and tumorigenesis. This review highlights the impact of gut microbiota dysbiosis on the development and progression of certain types of cancers and discusses the potential for developing new therapeutic strategies against cancer by manipulating the gut microbiota. By interacting with the host microbiota, we may be able to enhance the effectiveness of anticancer therapies and open new avenues for improving patient outcomes.
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Affiliation(s)
- Amer H. Asseri
- Biochemistry Department, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia
- Center for Artificial Intelligence in Precision Medicines, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Tahani Bakhsh
- Department of Biology, College of Science, University of Jeddah, Jeddah, Saudi Arabia
| | | | - Sajad Ali
- Department of Biotechnology, Yeungnam University, Gyeongsan, Republic of Korea
| | - Irfan A. Rather
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia
- Centre of Excellence in Bionanoscience Research, King Abdulaziz University, Jeddah, Saudi Arabia
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Lozano-Ojalvo D, Chen X, Dunkin D, Agashe C, Baker MG, Bird JA, Molina E, Nowak-Wegrzyn A, Berin MC. Untargeted serum metabolomic analysis reveals a role for purinergic signaling in FPIES. J Allergy Clin Immunol 2023; 151:797-802. [PMID: 36306938 PMCID: PMC9994238 DOI: 10.1016/j.jaci.2022.09.035] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 08/12/2022] [Accepted: 09/01/2022] [Indexed: 11/17/2022]
Abstract
BACKGROUND Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy with a typical onset in infancy. Its symptoms are distinct from those of IgE-mediated food allergies and include severe repetitive vomiting, lethargy, and pallor. FPIES reactions are associated with TH17 cytokines and a systemic innate immune activation; however, the link between immune activation and symptoms is poorly understood. OBJECTIVE Our aim was to use an untargeted metabolomics approach to identify novel pathways associated with FPIES reactions. METHODS Serum samples were obtained before, during, and after oral food challenge (OFC) (10 subjects with FPIES and 10 asymptomatic subjects), and they were analyzed by untargeted metabolomics. Two-way ANOVA with false discovery rate adjustment was used for analysis of metabolites. Stomach and duodenal biopsy specimens from non-FPIES donors were stimulated with adenosine in vitro and serotonin measured by immunoassay. RESULTS The levels of a total of 34 metabolites, including inosine and urate of the purine signaling pathway, were increased during OFCs performed on the patients with symptomatic FPIES compared with the levels found for asymptomatic subjects. Expression of the purine receptors P2RX7 and P2RY10 and the ectonucleotidase CD73 in peripheral blood was significantly reduced after OFC of the patients with FPIES. The level of the serotonin metabolite 5-hydroxyindoleacetate was significantly elevated after reaction. Adenosine stimulation of gastric and duodenal biopsy specimens from FPIES-free donors induced a significant release of serotonin, suggesting a link between purinergic pathway activation and serotonin release. CONCLUSIONS Activation of the purinergic pathway during FPIES reactions provides a possible mechanism connecting inflammation and vomiting by triggering serotonin release from gastric and duodenal mucosa.
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Affiliation(s)
- Daniel Lozano-Ojalvo
- Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York; Jaffe Food Allergy Institute, Icahn School of Medicine at Mount Sinai, New York; Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York
| | - Xin Chen
- Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York; Pediatric Gastroenterology, Icahn School of Medicine at Mount Sinai, New York
| | - David Dunkin
- Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York; Pediatric Gastroenterology, Icahn School of Medicine at Mount Sinai, New York
| | - Charuta Agashe
- Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York; Jaffe Food Allergy Institute, Icahn School of Medicine at Mount Sinai, New York
| | - Mary Grace Baker
- Jaffe Food Allergy Institute, Icahn School of Medicine at Mount Sinai, New York
| | - J Andrew Bird
- Department of Pediatrics, Division of Allergy and Immunology, University of Texas Southwestern Medical Center, Dallas
| | - Elena Molina
- Instituto de Investigación en Ciencias de la Alimentación CIAL, Madrid
| | - Anna Nowak-Wegrzyn
- Department of Pediatrics, New York University Grossman School of Medicine, Hassenfeld Children's Hospital, New York; Department of Pediatrics, Gastroenterology and Nutrition, Collegium Medicum, University of Warmia and Mazury, Olsztyn, Poland
| | - M Cecilia Berin
- Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York; Jaffe Food Allergy Institute, Icahn School of Medicine at Mount Sinai, New York; Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York.
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Glutamine increases stability of TPH1 mRNA via p38 mitogen-activated kinase in mouse mastocytoma cells. Mol Biol Rep 2023; 50:267-277. [PMID: 36331742 PMCID: PMC9884262 DOI: 10.1007/s11033-022-07693-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 06/07/2022] [Accepted: 06/08/2022] [Indexed: 11/06/2022]
Abstract
Expression changes for tryptophan hydroxylase 1 (TPH1), the rate-limiting enzyme in serotonin synthesis, by environmental glutamine (GLN) were examined in mouse mastocytoma-derived P815-HTR cells. GLN-treated cells exhibited a robust increase in TPH1 mRNA after a 6 h exposure to GLN. 6-Diazo-5-oxo-L-norleucine (DON), a glutamine-utilizing glutaminase inhibitor, significantly inhibited the GLN-induction of TPH1 mRNA. Nuclear run-on assays and mRNA decay experiments demonstrated that the primary mechanism leading to increased TPH1 mRNA levels was not due to transcriptional changes, but rather due to increased TPH1 RNA stability induced by GLN. Treatment with GLN also led to activation of p38 MAP kinase, but not p42/44 MAPK. In addition, SB203580, a p38 MAP kinase specific inhibitor, completely abolished the GLN-mediated increase of TPH1 mRNA levels, suggesting the pathway stabilizing TPH1 mRNA might be mediated by the activated p38 MAP kinase pathway. Additionally, SB203580 significantly reduced the stability of TPH1 mRNA, and this reduction of the stability was not affected by GLN in the culture medium, implying a sequential signaling from GLN being mediated by p38 MAP kinase, resulting in alteration of TPH1 mRNA stability. TPH1 mRNA stability loss was also dependent on de novo protein synthesis as shown by treatment of cells with a transcriptional/translational blocker. We provide evidence that TPH1 mRNA levels are increased in response to increased exogenous GLN in mouse mastocytoma cells via a stabilization of TPH1 mRNA due to the activity of the p38 MAP kinase.
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Mercado-Perez A, Beyder A. Gut feelings: mechanosensing in the gastrointestinal tract. Nat Rev Gastroenterol Hepatol 2022; 19:283-296. [PMID: 35022607 PMCID: PMC9059832 DOI: 10.1038/s41575-021-00561-y] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/22/2021] [Indexed: 12/11/2022]
Abstract
The primary function of the gut is to procure nutrients. Synchronized mechanical activities underlie nearly all its endeavours. Coordination of mechanical activities depends on sensing of the mechanical forces, in a process called mechanosensation. The gut has a range of mechanosensory cells. They function either as specialized mechanoreceptors, which convert mechanical stimuli into coordinated physiological responses at the organ level, or as non-specialized mechanosensory cells that adjust their function based on the mechanical state of their environment. All major cell types in the gastrointestinal tract contain subpopulations that act as specialized mechanoreceptors: epithelia, smooth muscle, neurons, immune cells, and others. These cells are tuned to the physical properties of the surrounding tissue, so they can discriminate mechanical stimuli from the baseline mechanical state. The importance of gastrointestinal mechanosensation has long been recognized, but the latest discoveries of molecular identities of mechanosensors and technical advances that resolve the relevant circuitry have poised the field to make important intellectual leaps. This Review describes the mechanical factors relevant for normal function, as well as the molecules, cells and circuits involved in gastrointestinal mechanosensing. It concludes by outlining important unanswered questions in gastrointestinal mechanosensing.
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Affiliation(s)
- Arnaldo Mercado-Perez
- Enteric NeuroScience Program (ENSP), Division of Gastroenterology & Hepatology, Mayo Clinic, Rochester, MN, USA
- Medical Scientist Training Program (MSTP), Mayo Clinic, Rochester, MN, USA
| | - Arthur Beyder
- Enteric NeuroScience Program (ENSP), Division of Gastroenterology & Hepatology, Mayo Clinic, Rochester, MN, USA.
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN, USA.
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8
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Lyu D, Kou G, Li S, Li L, Li B, Zhou R, Yang X, Tian W, Li Y, Zuo X. Digital Spatial Profiling Reveals Functional Shift of Enterochromaffin Cell in Patients With Ulcerative Colitis. Front Cell Dev Biol 2022; 10:841090. [PMID: 35465329 PMCID: PMC9023741 DOI: 10.3389/fcell.2022.841090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 02/21/2022] [Indexed: 11/30/2022] Open
Abstract
As a major component of the enteroendocrine system, enterochromaffin (EC) cells play a key role in ulcerative colitis (UC). However, the scarcity of EC cells has limited the investigation of their function. In this study, we applied digital spatial profiling to acquire transcriptomic data for EC cells and other epithelial cells from colonoscopic biopsy samples from eight patients with UC and seven healthy controls. Differential expression analysis, gene set enrichment analysis, and weighted gene coexpression network analysis were performed to identify differentially expressed genes and pathways and coexpression networks. Results were validated using an online dataset obtained by single-cell RNA sequencing, along with immunofluorescence staining and quantitative real-time PCR. In healthy participants, 10 genes were significantly enriched in EC cells, functionally concentrated in protein and bioamine synthesis. A coexpression network containing 17 hub genes, including TPH1, CHGA, and GCLC, was identified in EC cells. In patients with UC, EC cells gained increased capacity for protein synthesis, along with novel immunological functions such as antigen processing and presentation, whereas chemical sensation was downregulated. The specific expression of CHGB and RGS2 in EC cells was confirmed by immunofluorescence staining. Our results illuminate the transcriptional signatures of EC cells in the human colon. EC cells’ newly observed functional shift from sensation to secretion and immunity indicates their pivotal role in UC.
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Affiliation(s)
- Dongping Lyu
- Department of Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
- Laboratory of Translational Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
| | - Guanjun Kou
- Department of Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
- Laboratory of Translational Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
| | - Shiyang Li
- Department of Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
- Advanced Medical Research Institute, Shandong University, Jinan, China
- Key Laboratory for Experimental Teratology of Ministry of Education, Shandong University, Jinan, China
| | - Lixiang Li
- Department of Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
- Laboratory of Translational Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
- Robot Engineering Laboratory for Precise Diagnosis and Therapy of GI Tumor, Qilu Hospital, Shandong University, Jinan, China
| | - Bing Li
- Department of Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
- Laboratory of Translational Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
| | - Ruchen Zhou
- Department of Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
- Laboratory of Translational Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
| | - Xiaoxiao Yang
- Department of Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
- Laboratory of Translational Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
| | - Wenyu Tian
- Advanced Medical Research Institute, Shandong University, Jinan, China
| | - Yanqing Li
- Department of Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
- Laboratory of Translational Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
- Robot Engineering Laboratory for Precise Diagnosis and Therapy of GI Tumor, Qilu Hospital, Shandong University, Jinan, China
| | - Xiuli Zuo
- Department of Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
- Laboratory of Translational Gastroenterology, Qilu Hospital, Shandong University, Jinan, China
- Robot Engineering Laboratory for Precise Diagnosis and Therapy of GI Tumor, Qilu Hospital, Shandong University, Jinan, China
- *Correspondence: Xiuli Zuo,
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Tao E, Zhu Z, Hu C, Long G, Chen B, Guo R, Fang M, Jiang M. Potential Roles of Enterochromaffin Cells in Early Life Stress-Induced Irritable Bowel Syndrome. Front Cell Neurosci 2022; 16:837166. [PMID: 35370559 PMCID: PMC8964523 DOI: 10.3389/fncel.2022.837166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 02/09/2022] [Indexed: 12/04/2022] Open
Abstract
Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal disorders, also known as disorders of the gut–brain interaction; however, the pathophysiology of IBS remains unclear. Early life stress (ELS) is one of the most common risk factors for IBS development. However, the molecular mechanisms by which ELS induces IBS remain unclear. Enterochromaffin cells (ECs), as a prime source of peripheral serotonin (5-HT), play a pivotal role in intestinal motility, secretion, proinflammatory and anti-inflammatory effects, and visceral sensation. ECs can sense various stimuli and microbiota metabolites such as short-chain fatty acids (SCFAs) and secondary bile acids. ECs can sense the luminal environment and transmit signals to the brain via exogenous vagal and spinal nerve afferents. Increasing evidence suggests that an ECs-5-HT signaling imbalance plays a crucial role in the pathogenesis of ELS-induced IBS. A recent study using a maternal separation (MS) animal model mimicking ELS showed that MS induced expansion of intestinal stem cells and their differentiation toward secretory lineages, including ECs, leading to ECs hyperplasia, increased 5-HT production, and visceral hyperalgesia. This suggests that ELS-induced IBS may be associated with increased ECs-5-HT signaling. Furthermore, ECs are closely related to corticotropin-releasing hormone, mast cells, neuron growth factor, bile acids, and SCFAs, all of which contribute to the pathogenesis of IBS. Collectively, ECs may play a role in the pathogenesis of ELS-induced IBS. Therefore, this review summarizes the physiological function of ECs and focuses on their potential role in the pathogenesis of IBS based on clinical and pre-clinical evidence.
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Affiliation(s)
- Enfu Tao
- Endoscopy Center and Gastrointestinal Laboratory, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, National Children’s Regional Medical Center, Hangzhou, China
- Wenling Maternal and Child Health Care Hospital, Wenling, China
| | - Zhenya Zhu
- Endoscopy Center and Gastrointestinal Laboratory, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, National Children’s Regional Medical Center, Hangzhou, China
| | - Chenmin Hu
- Endoscopy Center and Gastrointestinal Laboratory, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, National Children’s Regional Medical Center, Hangzhou, China
| | - Gao Long
- Endoscopy Center and Gastrointestinal Laboratory, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, National Children’s Regional Medical Center, Hangzhou, China
| | - Bo Chen
- Endoscopy Center and Gastrointestinal Laboratory, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, National Children’s Regional Medical Center, Hangzhou, China
| | - Rui Guo
- Endoscopy Center and Gastrointestinal Laboratory, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, National Children’s Regional Medical Center, Hangzhou, China
| | - Marong Fang
- Institute of Neuroscience and Gastrointestinal Laboratory, Children’s Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Mizu Jiang
- Department of Gastroenterology, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, National Children’s Regional Medical Center, Hangzhou, China
- *Correspondence: Mizu Jiang,
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10
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Geesala R, Lin YM, Zhang K, Shi XZ. Targeting Mechano-Transcription Process as Therapeutic Intervention in Gastrointestinal Disorders. Front Pharmacol 2021; 12:809350. [PMID: 34992543 PMCID: PMC8724579 DOI: 10.3389/fphar.2021.809350] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 12/06/2021] [Indexed: 12/16/2022] Open
Abstract
Mechano-transcription is a process whereby mechanical stress alters gene expression. The gastrointestinal (GI) tract is composed of a series of hollow organs, often encountered by transient or persistent mechanical stress. Recent studies have revealed that persistent mechanical stress is present in obstructive, functional, and inflammatory disorders and alters gene transcription in these conditions. Mechano-transcription of inflammatory molecules, pain mediators, pro-fibrotic and growth factors has been shown to play a key role in the development of motility dysfunction, visceral hypersensitivity, inflammation, and fibrosis in the gut. In particular, mechanical stress-induced cyclooxygenase-2 (COX-2) and certain pro-inflammatory mediators in gut smooth muscle cells are responsible for motility dysfunction and inflammatory process. Mechano-transcription of pain mediators such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) may lead to visceral hypersensitivity. Emerging evidence suggests that mechanical stress in the gut also leads to up-regulation of certain proliferative and pro-fibrotic mediators such as connective tissue growth factor (CTGF) and osteopontin (OPN), which may contribute to fibrostenotic Crohn's disease. In this review, we will discuss the pathophysiological significance of mechanical stress-induced expression of pro-inflammatory molecules, pain mediators, pro-fibrotic and growth factors in obstructive, inflammatory, and functional bowel disorders. We will also evaluate potential therapeutic targets of mechano-transcription process for the management of these disorders.
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11
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Microbiomics in Collusion with the Nervous System in Carcinogenesis: Diagnosis, Pathogenesis and Treatment. Microorganisms 2021; 9:microorganisms9102129. [PMID: 34683450 PMCID: PMC8538279 DOI: 10.3390/microorganisms9102129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/23/2021] [Accepted: 09/27/2021] [Indexed: 11/17/2022] Open
Abstract
The influence of the naturally occurring population of microbes on various human diseases has been a topic of much recent interest. Not surprisingly, continuously growing attention is devoted to the existence of a gut brain axis, where the microbiota present in the gut can affect the nervous system through the release of metabolites, stimulation of the immune system, changing the permeability of the blood–brain barrier or activating the vagus nerves. Many of the methods that stimulate the nervous system can also lead to the development of cancer by manipulating pathways associated with the hallmarks of cancer. Moreover, neurogenesis or the creation of new nervous tissue, is associated with the development and progression of cancer in a similar manner as the blood and lymphatic systems. Finally, microbes can secrete neurotransmitters, which can stimulate cancer growth and development. In this review we discuss the latest evidence that support the importance of microbiota and peripheral nerves in cancer development and dissemination.
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12
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Hinman SS, Huling J, Wang Y, Wang H, Bretherton RC, DeForest CA, Allbritton NL. Magnetically-propelled fecal surrogates for modeling the impact of solid-induced shear forces on primary colonic epithelial cells. Biomaterials 2021; 276:121059. [PMID: 34412014 PMCID: PMC8405591 DOI: 10.1016/j.biomaterials.2021.121059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 07/16/2021] [Accepted: 08/04/2021] [Indexed: 12/27/2022]
Abstract
The colonic epithelium is continuously exposed to an array of biological and mechanical stimuli as its luminal contents are guided over the epithelial surface through regulated smooth muscle contraction. In this report, the propulsion of solid fecal contents over the colonic epithelium is recapitulated through noninvasive actuation of magnetic agarose hydrogels over primary intestinal epithelial cultures, in contrast to the vast majority of platforms that apply shear forces through liquid microflow. Software-controlled magnetic stepper motors enable experimental control over the frequency and velocity of these events to match in vivo propulsive contractions, while the integration of standardized well plate spacing facilitates rapid integration into existing assay pipelines. The application of these solid-induced shear forces did not deleteriously affect cell monolayer surface coverage, viability, or transepithelial electrical resistance unless the device parameters were raised to a 50× greater contraction frequency and 4× greater fecal velocity than those observed in healthy humans. At a frequency and velocity that is consistent with average human colonic motility, differentiation of the epithelial cells into absorptive and goblet cell phenotypes was not affected. Protein secretion was modulated with a two-fold increase in luminal mucin-2 secretion and a significant reduction in basal interleukin-8 secretion. F-actin, zonula occludens-1, and E-cadherin were each present in their proper basolateral locations, similar to those of static control cultures. While cellular height was unaffected by magnetic agarose propulsion, several alterations in lateral morphology were observed including decreased circularity and compactness, and an increase in major axis length, which align with surface epithelial cell morphologies observed in vivo and may represent early markers of luminal exfoliation. This platform will be of widespread utility for the investigation of fecal propulsive forces on intestinal physiology, shedding light on how the colonic epithelium responds to mechanical cues.
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Affiliation(s)
- Samuel S Hinman
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Jennifer Huling
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina State University, Raleigh, NC, USA
| | - Yuli Wang
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Hao Wang
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Ross C Bretherton
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Cole A DeForest
- Department of Bioengineering, University of Washington, Seattle, WA, USA; Department of Chemical Engineering, University of Washington, Seattle, WA, USA
| | - Nancy L Allbritton
- Department of Bioengineering, University of Washington, Seattle, WA, USA.
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13
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Yang X, Lou J, Shan W, Ding J, Jin Z, Hu Y, Du Q, Liao Q, Xie R, Xu J. Pathophysiologic Role of Neurotransmitters in Digestive Diseases. Front Physiol 2021; 12:567650. [PMID: 34194334 PMCID: PMC8236819 DOI: 10.3389/fphys.2021.567650] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 05/06/2021] [Indexed: 01/09/2023] Open
Abstract
Neurotransmitters are special molecules that serve as messengers in chemical synapses between neurons, cells, or receptors, including catecholamines, serotonin, dopamine, and other neurotransmitters, which play an important role in both human physiology and pathology. Compelling evidence has indicated that neurotransmitters have an important physiological role in various digestive diseases. They act as ligands in combination with central or peripheral receptors, and transmits signals through chemical synapses, which are involved in regulating the physiological and pathological processes of the digestive tract organs. For instance, neurotransmitters regulate blood circulation and affect intestinal movement, nutrient absorption, the gastrointestinal innate immune system, and the microbiome. In this review, we will focus on the role of neurotransmitters in the pathogenesis of digestive tract diseases to provide novel therapeutic targets for new drug development in digestive diseases.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Rui Xie
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Jingyu Xu
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
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14
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Suga N, Murakami A, Arimitsu H, Nakamura T, Nakamura Y, Kato Y. Luteolin suppresses 5-hydroxytryptamine elevation in stimulated RBL-2H3 cells and experimental colitis mice. J Clin Biochem Nutr 2021; 69:20-27. [PMID: 34376910 PMCID: PMC8325766 DOI: 10.3164/jcbn.20-192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 12/20/2020] [Indexed: 01/11/2023] Open
Abstract
Increased 5-hydroxytryptamine may be associated with the development and progression of inflammatory bowel disease. In this study, we examined the suppressive effect of flavonoids on the increased intra- and extracellular 5-hydroxytryptamine levels in rat mast RBL-2H3 cells, known to produce 5-hydroxytryptamine by the phorbol 12-myristate 13-acetate stimulation. Among the flavonoids examined, luteolin and quercetin significantly reduced the cellular 5-hydroxytryptamine concentration. Gene and protein expression analyses revealed that luteolin significantly suppressed cellular tryptophan hydroxylase 1 expression induced by phorbol 12-myristate 13-acetate stimulation. Mitogen-activated protein kinase/extracellular signal-regulated kinase signaling was also suppressed by luteolin, suggesting that this pathway is one of targets of 5-hydroxytryptamine modulation by luteolin. An in vivo experimental colitis model was prepared by administering 2.5% dextran sodium sulfate in drinking water to C57BL/6 mice for seven days. The ingestion of 0.1% dietary luteolin suppressed the increasing 5-hydroxytryptamine in the colorectal mucosa. In conclusion, luteolin possesses a suppressive effect on extensive 5-hydroxytryptamine formation in both experimental RBL-2H3 cells and colitis models.
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Affiliation(s)
- Naoko Suga
- Graduate School of Human Science and Environment, University of Hyogo, Himeji, Hyogo 670-0092, Japan
| | - Akira Murakami
- Graduate School of Human Science and Environment, University of Hyogo, Himeji, Hyogo 670-0092, Japan.,Research Institute for Food and Nutritional Sciences, University of Hyogo, Himeji, Hyogo 670-0092, Japan
| | - Hideyuki Arimitsu
- Graduate School of Human Science and Environment, University of Hyogo, Himeji, Hyogo 670-0092, Japan.,Research Institute for Food and Nutritional Sciences, University of Hyogo, Himeji, Hyogo 670-0092, Japan
| | - Toshiyuki Nakamura
- Graduate School of Environmental and Life Science, Okayama University, Okayama, Okayama 700-8530, Japan
| | - Yoshimasa Nakamura
- Graduate School of Environmental and Life Science, Okayama University, Okayama, Okayama 700-8530, Japan
| | - Yoji Kato
- Graduate School of Human Science and Environment, University of Hyogo, Himeji, Hyogo 670-0092, Japan.,Research Institute for Food and Nutritional Sciences, University of Hyogo, Himeji, Hyogo 670-0092, Japan
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15
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van Son J, Koekkoek LL, La Fleur SE, Serlie MJ, Nieuwdorp M. The Role of the Gut Microbiota in the Gut-Brain Axis in Obesity: Mechanisms and Future Implications. Int J Mol Sci 2021; 22:ijms22062993. [PMID: 33804250 PMCID: PMC7999163 DOI: 10.3390/ijms22062993] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 03/12/2021] [Accepted: 03/13/2021] [Indexed: 12/17/2022] Open
Abstract
Interaction between the gut and the brain is essential for energy homeostasis. In obesity, this homeostasis is disrupted, leading to a positive energy balance and weight gain. Obesity is a global epidemic that affects individual health and strains the socioeconomic system. Microbial dysbiosis has long been reported in obesity and obesity-related disorders. More recent literature has focused on the interaction of the gut microbiota and its metabolites on human brain and behavior. Developing strategies that target the gut microbiota could be a future approach for the treatment of obesity. Here, we review the microbiota–gut–brain axis and possible therapeutic options.
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Affiliation(s)
- Jamie van Son
- Department of Endocrinology and Metabolism, Amsterdam UMC, location AMC, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands; (J.v.S.); (L.L.K.); (S.E.L.F.); (M.J.S.)
- Department of Vascular Medicine, Amsterdam UMC, Location AMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Laura L. Koekkoek
- Department of Endocrinology and Metabolism, Amsterdam UMC, location AMC, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands; (J.v.S.); (L.L.K.); (S.E.L.F.); (M.J.S.)
| | - Susanne E. La Fleur
- Department of Endocrinology and Metabolism, Amsterdam UMC, location AMC, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands; (J.v.S.); (L.L.K.); (S.E.L.F.); (M.J.S.)
| | - Mireille J. Serlie
- Department of Endocrinology and Metabolism, Amsterdam UMC, location AMC, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands; (J.v.S.); (L.L.K.); (S.E.L.F.); (M.J.S.)
| | - Max Nieuwdorp
- Department of Vascular Medicine, Amsterdam UMC, Location AMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
- Correspondence:
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16
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Gunn D, Murthy R, Major G, Wilkinson-Smith V, Hoad C, Marciani L, Remes-Troche J, Gill S, Rossi M, Harris H, Ahn-Jarvis J, Warren F, Whelan K, Spiller R. Contrasting effects of viscous and particulate fibers on colonic fermentation in vitro and in vivo, and their impact on intestinal water studied by MRI in a randomized trial. Am J Clin Nutr 2020; 112:595-602. [PMID: 32619212 DOI: 10.1093/ajcn/nqaa173] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 06/11/2020] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Wheat bran, nopal, and psyllium are examples of particulate, viscous and particulate, and viscous fibers, respectively, with laxative properties yet contrasting fermentability. OBJECTIVES We assessed the fermentability of these fibers in vitro and their effects on intestinal function relevant to laxation in vivo using MRI. METHODS Each fiber was predigested prior to measuring gas production in vitro during 48-h anaerobic incubation with healthy fecal samples. We performed a randomized, 3-way crossover trial in 14 healthy volunteers who ingested 7.5 g fiber twice on the day prior to study initiation and once with the study test meal. Serial MRI scans obtained after fasting and hourly for 4 h following meal ingestion were used to assess small bowel water content (SBWC), colonic volumes, and T1 of the ascending colon (T1AC) as measures of colonic water. Breath samples for hydrogen analysis were obtained while patients were in the fasted state and every 30 min for 4 h following meal ingestion. RESULTS In vitro, the onset of gas production was significantly delayed with psyllium (mean ± SD: 14 ± 5 h) compared with wheat bran (6 ± 2 h, P = 0.003) and was associated with a smaller total gas volume (P = 0.01). Prefeeding all 3 fibers for 24 h was associated with an increased fasting T1AC (>75% of values >90th centile of the normal range). There was a further rise during the 4 h after psyllium (0.3 ± 0.3 s P = 0.009), a fall with wheat bran (-0.2 ± 0.2 s; P = 0.02), but no change with nopal (0.0 ± 0.1 s, P = 0.2). SBWC increased for all fibers; nopal stimulated more water than wheat bran [AUC mean (95% CI) difference: 7.1 (0.6, 13.8) L/min, P = 0.03].Breath hydrogen rose significantly after wheat bran and nopal but not after psyllium (P < 0.0001). CONCLUSION Both viscous and particulate fibers are equally effective at increasing colonic T1 over a period of 24 h. Mechanisms include water trapping in the small bowel by viscous fibers and delivery of substrates to the colonic microbiota by more fermentable particulate fiber. This trial was registered at clinicaltrials.gov as NCT03263065.
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Affiliation(s)
- David Gunn
- NIHR Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and the University of Nottingham, Nottingham, United Kingdom.,Nottingham Digestive Diseases Centre, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Rajani Murthy
- Nottingham Digestive Diseases Centre, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Giles Major
- NIHR Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and the University of Nottingham, Nottingham, United Kingdom.,Nottingham Digestive Diseases Centre, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Victoria Wilkinson-Smith
- NIHR Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and the University of Nottingham, Nottingham, United Kingdom.,Nottingham Digestive Diseases Centre, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Caroline Hoad
- NIHR Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and the University of Nottingham, Nottingham, United Kingdom.,Sir Peter Mansfield Imaging Centre, University of Nottingham, United Kingdom
| | - Luca Marciani
- NIHR Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and the University of Nottingham, Nottingham, United Kingdom.,Nottingham Digestive Diseases Centre, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Jose Remes-Troche
- Digestive Physiology and Motility Lab, Medical Biological Research Institute, University of Veracruz, Veracruz, Mexico
| | - Samantha Gill
- King's College London, Department of Nutritional Sciences, London, United Kingdom
| | - Megan Rossi
- King's College London, Department of Nutritional Sciences, London, United Kingdom
| | - Hannah Harris
- Quadram Institute of Biosciences, Food, Innovation and Health, Norwich Research Park, Norwich, United Kingdom
| | - Jennifer Ahn-Jarvis
- Quadram Institute of Biosciences, Food, Innovation and Health, Norwich Research Park, Norwich, United Kingdom
| | - Fred Warren
- Quadram Institute of Biosciences, Food, Innovation and Health, Norwich Research Park, Norwich, United Kingdom
| | - Kevin Whelan
- King's College London, Department of Nutritional Sciences, London, United Kingdom
| | - Robin Spiller
- NIHR Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and the University of Nottingham, Nottingham, United Kingdom.,Nottingham Digestive Diseases Centre, School of Medicine, University of Nottingham, Nottingham, United Kingdom
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17
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Kannen V, Bader M, Sakita JY, Uyemura SA, Squire JA. The Dual Role of Serotonin in Colorectal Cancer. Trends Endocrinol Metab 2020; 31:611-625. [PMID: 32439105 DOI: 10.1016/j.tem.2020.04.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 03/18/2020] [Accepted: 04/27/2020] [Indexed: 02/07/2023]
Abstract
Serotonin (5-HT) has complex effects on the central nervous system (CNS), neuroendocrine mechanisms, immunological reactions, intestinal microbiome, and cancer. It has been associated with more severe signs and symptoms of colitis, as well as promoting colorectal cancer (CRC) cells toward expansion. However, recent findings revealed that impairments in 5-HT synthesis lead to high levels of DNA damage in colonocytes, which is linked with inflammatory reactions promoting the development of CRC. Here, we review the diverse roles of 5-HT in intestinal homeostasis and in CRC and discuss how improved understanding of the modulation of the 5-HT pathway could be helpful for the design of novel anticancer therapies.
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Affiliation(s)
- Vinicius Kannen
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Canada; Department of Genetics, University of Sao Paulo, Ribeirao Preto, Brazil.
| | - Michael Bader
- Max-Delbrück-Center for Molecular Medicine, Berlin, Germany; Charité, University Medicine Berlin, Germany; Institute for Biology, University of Lübeck, Lübeck, Germany
| | - Juliana Y Sakita
- Department of Genetics, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Sergio A Uyemura
- Department of Toxicology, Bromatology, and Clinical Analysis, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Jeremy A Squire
- Department of Genetics, University of Sao Paulo, Ribeirao Preto, Brazil; Department of Pathology and Molecular Medicine, Queen's University, Kingston, Canada
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18
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Kaelberer MM, Rupprecht LE, Liu WW, Weng P, Bohórquez DV. Neuropod Cells: The Emerging Biology of Gut-Brain Sensory Transduction. Annu Rev Neurosci 2020; 43:337-353. [PMID: 32101483 PMCID: PMC7573801 DOI: 10.1146/annurev-neuro-091619-022657] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Guided by sight, scent, texture, and taste, animals ingest food. Once ingested, it is up to the gut to make sense of the food's nutritional value. Classic sensory systems rely on neuroepithelial circuits to convert stimuli into signals that guide behavior. However, sensation of the gut milieu was thought to be mediated only by the passive release of hormones until the discovery of synapses in enteroendocrine cells. These are gut sensory epithelial cells, and those that form synapses are referred to as neuropod cells. Neuropod cells provide the foundation for the gut to transduce sensory signals from the intestinal milieu to the brain through fast neurotransmission onto neurons, including those of the vagus nerve. These findings have sparked a new field of exploration in sensory neurobiology-that of gut-brain sensory transduction.
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Affiliation(s)
- Melanie Maya Kaelberer
- Gut-Brain Neurobiology Laboratory, Department of Medicine, School of Medicine, Duke University, Durham, North Carolina 27710, USA;
| | - Laura E Rupprecht
- Gut-Brain Neurobiology Laboratory, Department of Medicine, School of Medicine, Duke University, Durham, North Carolina 27710, USA;
| | - Winston W Liu
- Gut-Brain Neurobiology Laboratory, Department of Medicine, School of Medicine, Duke University, Durham, North Carolina 27710, USA;
- School of Medicine, Duke University, Durham, North Carolina 27710, USA
| | - Peter Weng
- Gut-Brain Neurobiology Laboratory, Department of Medicine, School of Medicine, Duke University, Durham, North Carolina 27710, USA;
- School of Medicine, Duke University, Durham, North Carolina 27710, USA
| | - Diego V Bohórquez
- Gut-Brain Neurobiology Laboratory, Department of Medicine, School of Medicine, Duke University, Durham, North Carolina 27710, USA;
- Department of Neurobiology, Duke University, Durham, North Carolina 27710, USA
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19
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Kaelberer MM, Rupprecht LE, Liu WW, Weng P, Bohórquez DV. Neuropod Cells: The Emerging Biology of Gut-Brain Sensory Transduction. Annu Rev Neurosci 2020. [PMID: 32101483 DOI: 10.1146/annurev‐neuro‐091619‐022657] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Guided by sight, scent, texture, and taste, animals ingest food. Once ingested, it is up to the gut to make sense of the food's nutritional value. Classic sensory systems rely on neuroepithelial circuits to convert stimuli into signals that guide behavior. However, sensation of the gut milieu was thought to be mediated only by the passive release of hormones until the discovery of synapses in enteroendocrine cells. These are gut sensory epithelial cells, and those that form synapses are referred to as neuropod cells. Neuropod cells provide the foundation for the gut to transduce sensory signals from the intestinal milieu to the brain through fast neurotransmission onto neurons, including those of the vagus nerve. These findings have sparked a new field of exploration in sensory neurobiology-that of gut-brain sensory transduction.
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Affiliation(s)
- Melanie Maya Kaelberer
- Gut-Brain Neurobiology Laboratory, Department of Medicine, School of Medicine, Duke University, Durham, North Carolina 27710, USA;
| | - Laura E Rupprecht
- Gut-Brain Neurobiology Laboratory, Department of Medicine, School of Medicine, Duke University, Durham, North Carolina 27710, USA;
| | - Winston W Liu
- Gut-Brain Neurobiology Laboratory, Department of Medicine, School of Medicine, Duke University, Durham, North Carolina 27710, USA; .,School of Medicine, Duke University, Durham, North Carolina 27710, USA
| | - Peter Weng
- Gut-Brain Neurobiology Laboratory, Department of Medicine, School of Medicine, Duke University, Durham, North Carolina 27710, USA; .,School of Medicine, Duke University, Durham, North Carolina 27710, USA
| | - Diego V Bohórquez
- Gut-Brain Neurobiology Laboratory, Department of Medicine, School of Medicine, Duke University, Durham, North Carolina 27710, USA; .,Department of Neurobiology, Duke University, Durham, North Carolina 27710, USA
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20
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Holton NW, Singhal M, Kumar A, Ticho AL, Manzella CR, Malhotra P, Jarava D, Saksena S, Dudeja PK, Alrefai WA, Gill RK. Hepatocyte nuclear factor-4α regulates expression of the serotonin transporter in intestinal epithelial cells. Am J Physiol Cell Physiol 2020; 318:C1294-C1304. [PMID: 32348179 PMCID: PMC7311735 DOI: 10.1152/ajpcell.00477.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 04/23/2020] [Accepted: 04/23/2020] [Indexed: 12/20/2022]
Abstract
The serotonin transporter (SERT) functions to regulate the availability of serotonin (5-HT) in the brain and intestine. An intestine-specific mRNA variant arising from a unique transcription start site and alternative promoter in the SERT gene has been identified (iSERT; spanning exon 1C). A decrease in SERT is implicated in several gut disorders, including inflammatory bowel diseases (IBD). However, little is known about mechanisms regulating the iSERT variant, and a clearer understanding is warranted for targeting SERT for the treatment of gut disorders. The current studies examined the expression of iSERT across different human intestinal regions and investigated its regulation by HNF4α (hepatic nuclear factor-4α), a transcription factor important for diverse cellular functions. iSERT mRNA abundance was highest in the human ileum and Caco-2 cell line. iSERT mRNA expression was downregulated by loss of HNF4α (but not HNF1α, HNF1β, or FOXA1) in Caco-2 cells. Overexpression of HNF4α increased iSERT mRNA concomitant with an increase in SERT protein. Progressive promoter deletion and site-directed mutagenesis revealed that the HNF4α response element spans nucleotides -1,163 to -1150 relative to the translation start site. SERT mRNA levels in the intestine were drastically reduced in the intestine-specific HNF4α-knockout mice relative to HNF4αFL/FL mice. Both HNF4α and SERT mRNA levels were also downregulated in mouse model of ileitis (SAMP) compared with AKR control mice. These results establish the transcriptional regulation of iSERT at the gut-specific internal promoter (hSERTp2) and have identified HNF4α as a critical modulator of basal SERT expression in the intestine.
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Affiliation(s)
- Nathaniel W Holton
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
| | - Megha Singhal
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
| | - Anoop Kumar
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
| | - Alexander L Ticho
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, Illinois
| | - Christopher R Manzella
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, Illinois
| | - Pooja Malhotra
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
| | - David Jarava
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
| | - Seema Saksena
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
- Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Pradeep K Dudeja
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
- Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Waddah A Alrefai
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
- Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Ravinder K Gill
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
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21
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Chandrasekaran B, Samarneh S, Jaber AMY, Kassab G, Agrawal N. Therapeutic Potentials of A2B Adenosine Receptor Ligands: Current Status and Perspectives. Curr Pharm Des 2020; 25:2741-2771. [PMID: 31333084 DOI: 10.2174/1381612825666190717105834] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 07/03/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND Adenosine receptors (ARs) are classified as A1, A2A, A2B, and A3 subtypes belong to the superfamily of G-protein coupled receptors (GPCRs). More than 40% of modern medicines act through either activation or inhibition of signaling processes associated with GPCRs. In particular, A2B AR signaling pathways are implicated in asthma, inflammation, cancer, ischemic hyperfusion, diabetes mellitus, cardiovascular diseases, gastrointestinal disorders, and kidney disease. METHODS This article reviews different disease segments wherein A2B AR is implicated and discusses the potential role of subtype-selective A2B AR ligands in the management of such diseases or disorders. All the relevant publications on this topic are reviewed and presented scientifically. RESULTS This review provides an up-to-date highlight of the recent advances in the development of novel and selective A2B AR ligands and their therapeutic role in treating various disease conditions. A special focus has been given to the therapeutic potentials of selective A2B AR ligands in the management of airway inflammatory conditions and cancer. CONCLUSIONS This systematic review demonstrates the current status and perspectives of A2B AR ligands as therapeutically useful agents that would assist medicinal chemists and pharmacologists in discovering novel and subtype-selective A2B AR ligands as potential drug candidates.
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Affiliation(s)
- Balakumar Chandrasekaran
- Faculty of Pharmacy, Philadelphia University-Jordan, P. O. Box: 1, Philadelphia University-19392, Amman, Jordan
| | - Sara Samarneh
- Faculty of Pharmacy, Philadelphia University-Jordan, P. O. Box: 1, Philadelphia University-19392, Amman, Jordan
| | - Abdul Muttaleb Yousef Jaber
- Faculty of Pharmacy, Philadelphia University-Jordan, P. O. Box: 1, Philadelphia University-19392, Amman, Jordan
| | - Ghadir Kassab
- Faculty of Pharmacy, Philadelphia University-Jordan, P. O. Box: 1, Philadelphia University-19392, Amman, Jordan
| | - Nikhil Agrawal
- College of Health Sciences, University of KwaZulu-Natal, P. O. Box: 4000, Westville, Durban, South Africa
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22
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Liu YL, Chen Y, Fan WT, Cao P, Yan J, Zhao XZ, Dong WG, Huang WH. Mechanical Distension Induces Serotonin Release from Intestine as Revealed by Stretchable Electrochemical Sensing. Angew Chem Int Ed Engl 2020; 59:4075-4081. [PMID: 31829491 DOI: 10.1002/anie.201913953] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 12/04/2019] [Indexed: 12/17/2022]
Abstract
The role of endogenous serotonin (5-HT) in gastrointestinal motility is still highly controversial. Although electrochemical techniques allow for direct and real-time recording of biomolecules, the dynamic monitoring of 5-HT release from elastic and tubular intestine during motor reflexes remains a great challenge because of the specific peristalsis patterns and inevitable passivation of the sensing interface. A stretchable sensor with antifouling and decontamination properties was assembled from gold nanotubes, titanium dioxide nanoparticles, and carbon nanotubes. The sandwich-like structure endowed the sensor with satisfying mechanical stability and electrochemical performance, high resistance against physical adsorption, and superior efficiency in the photodegradation of biofouling molecules. Insertion of the sensor into the lumen of rat ileum (the last section of the small intestine) successfully mimics intestinal peristalsis, and simultaneous real-time monitoring of distension-evoked 5-HT release was possible for the first time. Our results unambiguously reveal that mechanical distension of the intestine induces endogenous 5-HT overflow, and 5-HT level is closely associated with the physiological or pathological states of the intestine.
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Affiliation(s)
- Yan-Ling Liu
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China
| | - Yan Chen
- Key Laboratory of Hubei Province for Digestive System Disease, Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Wen-Ting Fan
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China
| | - Pan Cao
- Key Laboratory of Hubei Province for Digestive System Disease, Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Jing Yan
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China
| | - Xing-Zhong Zhao
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Wei-Guo Dong
- Key Laboratory of Hubei Province for Digestive System Disease, Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Wei-Hua Huang
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China
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Liu Y, Chen Y, Fan W, Cao P, Yan J, Zhao X, Dong W, Huang W. Mechanical Distension Induces Serotonin Release from Intestine as Revealed by Stretchable Electrochemical Sensing. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201913953] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Yan‐Ling Liu
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education) College of Chemistry and Molecular Sciences Wuhan University Wuhan 430072 China
| | - Yan Chen
- Key Laboratory of Hubei Province for Digestive System Disease Department of Gastroenterology Renmin Hospital of Wuhan University Wuhan 430060 China
| | - Wen‐Ting Fan
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education) College of Chemistry and Molecular Sciences Wuhan University Wuhan 430072 China
| | - Pan Cao
- Key Laboratory of Hubei Province for Digestive System Disease Department of Gastroenterology Renmin Hospital of Wuhan University Wuhan 430060 China
| | - Jing Yan
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education) College of Chemistry and Molecular Sciences Wuhan University Wuhan 430072 China
| | - Xing‐Zhong Zhao
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education School of Physics and Technology Wuhan University Wuhan 430072 China
| | - Wei‐Guo Dong
- Key Laboratory of Hubei Province for Digestive System Disease Department of Gastroenterology Renmin Hospital of Wuhan University Wuhan 430060 China
| | - Wei‐Hua Huang
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education) College of Chemistry and Molecular Sciences Wuhan University Wuhan 430072 China
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24
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Effects of Qigong Exercise on Non-Motor Symptoms and Inflammatory Status in Parkinson's Disease: A Protocol for a Randomized Controlled Trial. MEDICINES 2019; 6:medicines6010013. [PMID: 30669324 PMCID: PMC6473798 DOI: 10.3390/medicines6010013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 01/04/2019] [Accepted: 01/16/2019] [Indexed: 12/26/2022]
Abstract
Background: Non-motor symptoms such as sleep disturbance, cognitive decline, fatigue, anxiety, and depression in Parkinson’s disease (PD) impact quality of life. Increased levels of pro-inflammatory cytokines in individuals with PD have been reported, which may contribute to non-motor symptoms. A mind-body exercise, Qigong, has demonstrated benefits across different medical conditions. However, a lack of evidence causes clinicians and patients to be uncertain about the effects of Qigong in individuals with PD. This study will examine the effects of Qigong on non-motor symptoms and inflammatory status in individuals with PD. Methods: Sixty individuals with PD will be recruited. Qigong and sham Qigong group (n = 30 for each) will receive a 12-week intervention. Participants will practice their assigned exercise at home (2×/day) and attend routinely group exercise meetings. Results: Clinical questionnaires and neuropsychological tests will measure non-motor symptoms including sleep quality (primary outcome). Biomarker assays will measure inflammatory status. A two-way mixed-design analysis of variance (ANOVA) will be utilized. Conclusions: This study may generate evidence for the benefits of Qigong on non-motor symptoms of PD and the effect on inflammatory status. Findings may lead to the development of a novel, safe, and cost-effective rehabilitation approach for individuals with PD.
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25
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Cives M, Pelle' E, Quaresmini D, Rizzo FM, Tucci M, Silvestris F. The Tumor Microenvironment in Neuroendocrine Tumors: Biology and Therapeutic Implications. Neuroendocrinology 2019; 109:83-99. [PMID: 30699437 DOI: 10.1159/000497355] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 01/30/2019] [Indexed: 12/12/2022]
Abstract
Neuroendocrine tumors (NETs) include a heterogeneous group of malignancies arising in the diffuse neuroendocrine system and characterized by indolent growth. Complex interactions take place among the cellular components of the microenvironment of these tumors, and the recognition of the molecular mediators of their interplay and cross talk is crucial to discover novel therapeutic targets. NET cells overexpress a plethora of proangiogenic molecules including vascular endothelial growth factor, platelet-derived growth factor, fibroblast growth factor, semaphorins, and angiopoietins that promote both recruitment and proliferation of endothelial cell precursors, thus resulting among the most vascularized cancers with a microvessel density 10-fold higher than epithelial tumors. Also, NETs operate multifaceted interactions with stromal cells, both at local and distant sites, and whether their paracrine secretion of serotonin, connective tissue growth factor, and transforming growth factor β primarily drives the fibroblast activation to enhance the tumor proliferation, on the other side NET-derived profibrotic factors accelerate the extracellular matrix remodeling and contribute to heart valves and/or mesenteric fibrosis development, namely, major complications of functioning NETs. However, at present, little is known on the immune landscape of NETs, but accumulating evidence shows that tumor-infiltrating neutrophils, mast cells, and/or macrophages concur to promote the neoangiogenic switch of these tumors by either direct or indirect mechanisms. On the other hand, immune checkpoint molecules are heterogeneously expressed in NETs' surrounding cells, and it is unclear whether or not tumor-infiltrating lymphocytes are antitumor armed within the microenvironment, given their low mutational load. Here, we review the current knowledge on both gastroenteropancreatic and pulmonary NETs' microenvironment as well as both established and innovative treatments aimed at targeting the tumor-host interplay.
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Affiliation(s)
- Mauro Cives
- Department of Biomedical Sciences and Human Oncology, University of Bari "Aldo Moro", Bari, Italy
| | - Eleonora Pelle'
- Department of Biomedical Sciences and Human Oncology, University of Bari "Aldo Moro", Bari, Italy
| | - Davide Quaresmini
- Department of Biomedical Sciences and Human Oncology, University of Bari "Aldo Moro", Bari, Italy
| | - Francesca Maria Rizzo
- Department of Biomedical Sciences and Human Oncology, University of Bari "Aldo Moro", Bari, Italy
| | - Marco Tucci
- Department of Biomedical Sciences and Human Oncology, University of Bari "Aldo Moro", Bari, Italy
| | - Franco Silvestris
- Department of Biomedical Sciences and Human Oncology, University of Bari "Aldo Moro", Bari, Italy,
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Alcaino C, Knutson KR, Treichel AJ, Yildiz G, Strege PR, Linden DR, Li JH, Leiter AB, Szurszewski JH, Farrugia G, Beyder A. A population of gut epithelial enterochromaffin cells is mechanosensitive and requires Piezo2 to convert force into serotonin release. Proc Natl Acad Sci U S A 2018; 115:E7632-E7641. [PMID: 30037999 PMCID: PMC6094143 DOI: 10.1073/pnas.1804938115] [Citation(s) in RCA: 154] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Enterochromaffin (EC) cells constitute the largest population of intestinal epithelial enteroendocrine (EE) cells. EC cells are proposed to be specialized mechanosensory cells that release serotonin in response to epithelial forces, and thereby regulate intestinal fluid secretion. However, it is unknown whether EE and EC cells are directly mechanosensitive, and if so, what the molecular mechanism of their mechanosensitivity is. Consequently, the role of EE and EC cells in gastrointestinal mechanobiology is unclear. Piezo2 mechanosensitive ion channels are important for some specialized epithelial mechanosensors, and they are expressed in mouse and human EC cells. Here, we use EC and EE cell lineage tracing in multiple mouse models to show that Piezo2 is expressed in a subset of murine EE and EC cells, and it is distributed near serotonin vesicles by superresolution microscopy. Mechanical stimulation of a subset of isolated EE cells leads to a rapid inward ionic current, which is diminished by Piezo2 knockdown and channel inhibitors. In these mechanosensitive EE cells force leads to Piezo2-dependent intracellular Ca2+ increase in isolated cells as well as in EE cells within intestinal organoids, and Piezo2-dependent mechanosensitive serotonin release in EC cells. Conditional knockout of intestinal epithelial Piezo2 results in a significant decrease in mechanically stimulated epithelial secretion. This study shows that a subset of primary EE and EC cells is mechanosensitive, uncovers Piezo2 as their primary mechanotransducer, defines the molecular mechanism of their mechanotransduction and mechanosensitive serotonin release, and establishes the role of epithelial Piezo2 mechanosensitive ion channels in regulation of intestinal physiology.
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Affiliation(s)
- Constanza Alcaino
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Mayo Clinic, Rochester, MN 55905
| | - Kaitlyn R Knutson
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Mayo Clinic, Rochester, MN 55905
| | - Anthony J Treichel
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Mayo Clinic, Rochester, MN 55905
| | - Gulcan Yildiz
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Mayo Clinic, Rochester, MN 55905
| | - Peter R Strege
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Mayo Clinic, Rochester, MN 55905
| | - David R Linden
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Mayo Clinic, Rochester, MN 55905
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN 55905
| | - Joyce H Li
- Division of Gastroenterology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01655
| | - Andrew B Leiter
- Division of Gastroenterology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01655
| | - Joseph H Szurszewski
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Mayo Clinic, Rochester, MN 55905
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN 55905
| | - Gianrico Farrugia
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Mayo Clinic, Rochester, MN 55905
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN 55905
| | - Arthur Beyder
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Mayo Clinic, Rochester, MN 55905;
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN 55905
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27
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Videlock EJ, Mahurkar-Joshi S, Hoffman JM, Iliopoulos D, Pothoulakis C, Mayer EA, Chang L. Sigmoid colon mucosal gene expression supports alterations of neuronal signaling in irritable bowel syndrome with constipation. Am J Physiol Gastrointest Liver Physiol 2018; 315:G140-G157. [PMID: 29565640 PMCID: PMC6109711 DOI: 10.1152/ajpgi.00288.2017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 03/01/2018] [Accepted: 03/05/2018] [Indexed: 01/31/2023]
Abstract
Peripheral factors likely play a role in at least a subset of irritable bowel syndrome (IBS) patients. Few studies have investigated mucosal gene expression using an unbiased approach. Here, we performed mucosal gene profiling in a sex-balanced sample to identify relevant signaling pathways and gene networks and compare with publicly available profiling data from additional cohorts. Twenty Rome III+ IBS patients [10 IBS with constipation (IBS-C), 10 IBS with diarrhea (IBS-D), 5 men/women each), and 10 age-/sex-matched healthy controls (HCs)] underwent sigmoidoscopy with biopsy for gene microarray analysis, including differential expression, weighted gene coexpression network analysis (WGCNA), gene set enrichment analysis, and comparison with publicly available data. Expression levels of 67 genes were validated in an expanded cohort, including the above samples and 18 additional participants (6 each of IBS-C, IBS-D, HCs) using NanoString nCounter technology. There were 1,270 differentially expressed genes (FDR < 0.05) in IBS-C vs. HCs but none in IBS or IBS-D vs. HCs. WGNCA analysis identified activation of the cAMP/protein kinase A signaling pathway. Nine of 67 genes were validated by the NanoString nCounter technology (FDR < 0.05) in the expanded sample. Comparison with publicly available microarray data from the Mayo Clinic and University of Nottingham supports the reproducibility of 17 genes from the microarray analysis and three of nine genes validated by nCounter in IBS-C vs. HCs. This study supports the involvement of peripheral mechanisms in IBS-C, particularly pathways mediating neuronal signaling. NEW & NOTEWORTHY Peripheral factors play a role in the pathophysiology of irritable bowel syndrome (IBS), which, to date, has been mostly evident in IBS with diarrhea. Here, we show that sigmoid colon mucosal gene expression profiles differentiate IBS with constipation from healthy controls. These profiling data and analysis of additional cohorts also support the concept that peripheral neuronal pathways contribute to IBS pathophysiology.
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Affiliation(s)
- Elizabeth J Videlock
- G. Oppenheimer Center for Neurobiology of Stress and Resilience, Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California , Los Angeles, California
| | - Swapna Mahurkar-Joshi
- G. Oppenheimer Center for Neurobiology of Stress and Resilience, Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California , Los Angeles, California
| | - Jill M Hoffman
- Inflammatory Bowel Disease Research Center, Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California , Los Angeles, California
| | - Dimitrios Iliopoulos
- Center for Systems Biomedicine, Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California , Los Angeles, California
| | - Charalabos Pothoulakis
- Inflammatory Bowel Disease Research Center, Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California , Los Angeles, California
| | - Emeran A Mayer
- G. Oppenheimer Center for Neurobiology of Stress and Resilience, Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California , Los Angeles, California
| | - Lin Chang
- G. Oppenheimer Center for Neurobiology of Stress and Resilience, Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California , Los Angeles, California
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Kannen V, Sakita JY, Carneiro ZA, Bader M, Alenina N, Teixeira RR, de Oliveira EC, Brunaldi MO, Gasparotto B, Sartori DC, Fernandes CR, Silva JS, Andrade MV, Silva WA, Uyemura SA, Garcia SB. Mast Cells and Serotonin Synthesis Modulate Chagas Disease in the Colon: Clinical and Experimental Evidence. Dig Dis Sci 2018; 63:1473-1484. [PMID: 29569002 DOI: 10.1007/s10620-018-5015-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 03/07/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND Trypanosoma cruzi (T. cruzi) infects millions of Latin Americans each year and can induce chagasic megacolon. Little is known about how serotonin (5-HT) modulates this condition. Aim We investigated whether 5-HT synthesis alters T. cruzi infection in the colon. MATERIALS AND METHODS Forty-eight paraffin-embedded samples from normal colon and chagasic megacolon were histopathologically analyzed (173/2009). Tryptophan hydroxylase 1 (Tph1) knockout (KO) mice and c-KitW-sh mice underwent T. cruzi infection together with their wild-type counterparts. Also, mice underwent different drug treatments (16.1.1064.60.3). RESULTS In both humans and experimental mouse models, the serotonergic system was activated by T. cruzi infection (p < 0.05). While treating Tph1KO mice with 5-HT did not significantly increase parasitemia in the colon (p > 0.05), rescuing its synthesis promoted trypanosomiasis (p < 0.01). T. cruzi-related 5-HT release (p < 0.05) seemed not only to increase inflammatory signaling, but also to enlarge the pericryptal macrophage and mast cell populations (p < 0.01). Knocking out mast cells reduced trypanosomiasis (p < 0.01), although it did not further alter the neuroendocrine cell number and Tph1 expression (p > 0.05). Further experimentation revealed that pharmacologically inhibiting mast cell activity reduced colonic infection (p < 0.01). A similar finding was achieved when 5-HT synthesis was blocked in c-KitW-sh mice (p > 0.05). However, inhibiting mast cell activity in Tph1KO mice increased colonic trypanosomiasis (p < 0.01). CONCLUSION We show that mast cells may modulate the T. cruzi-related increase of 5-HT synthesis in the intestinal colon.
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Affiliation(s)
- Vinicius Kannen
- Department of Toxicology, Bromatology, and Clinical Analysis, University of Sao Paulo, Ribeirão Preto, 14040-903, Brazil.
- Department of Pathology, University of Sao Paulo, Ribeirão Preto, Brazil.
| | - Juliana Y Sakita
- Department of Toxicology, Bromatology, and Clinical Analysis, University of Sao Paulo, Ribeirão Preto, 14040-903, Brazil
| | - Zumira A Carneiro
- Department of Toxicology, Bromatology, and Clinical Analysis, University of Sao Paulo, Ribeirão Preto, 14040-903, Brazil
| | - Michael Bader
- Max Delbrück Center for Molecular Medicine, Berlin, Germany
- Charité University Medicine Berlin, Berlin, Germany
- Berlin Institute of Health (BIH), Berlin, Germany
| | - Natalia Alenina
- Max Delbrück Center for Molecular Medicine, Berlin, Germany
- Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg, Russia
| | - Regina R Teixeira
- Department of Toxicology, Bromatology, and Clinical Analysis, University of Sao Paulo, Ribeirão Preto, 14040-903, Brazil
| | | | | | - Bianca Gasparotto
- Department of Toxicology, Bromatology, and Clinical Analysis, University of Sao Paulo, Ribeirão Preto, 14040-903, Brazil
| | - Daniela C Sartori
- Department of Biochemistry and Immunology, University of São Paulo, Ribeirão Preto, Brazil
| | | | - João S Silva
- Department of Biochemistry and Immunology, University of São Paulo, Ribeirão Preto, Brazil
| | - Marcus V Andrade
- Department of Clinical Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Wilson A Silva
- Department of Genetics, University of Sao Paulo, Ribeirão Preto, Brazil
| | - Sergio A Uyemura
- Department of Toxicology, Bromatology, and Clinical Analysis, University of Sao Paulo, Ribeirão Preto, 14040-903, Brazil
| | - Sérgio B Garcia
- Department of Pathology, University of Sao Paulo, Ribeirão Preto, Brazil
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Beyder A. In Pursuit of the Epithelial Mechanosensitivity Mechanisms. Front Endocrinol (Lausanne) 2018; 9:804. [PMID: 30697191 PMCID: PMC6340920 DOI: 10.3389/fendo.2018.00804] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 12/21/2018] [Indexed: 01/08/2023] Open
Abstract
Mechanosensation is critical for normal gastrointestinal (GI) function. Disruption in GI mechanosensation leads to human diseases. Mechanical forces in the GI tract are sensed by specialized mechanosensory cells, as well as non-specialized mechanosensors, like smooth muscle cells. Together, these cellular mechanosensors orchestrate physiologic responses. GI epithelium is at the interface of the body and the environment. It encounters a variety of mechanical forces that range from shear stress due to flow of luminal contents to extrinsic compression due to smooth muscle contraction. Mechanical forces applied to the GI mucosa lead to a large outflow of serotonin, and since serotonin is concentrated in a single type of an epithelial cell, called enterochromaffin cell (ECC), it was assumed that ECC is mechanosensitive. Recent studies show that a subset of ECCs is indeed mechanosensitive and that Piezo2 mechanosensitive ion channels are necessary for coupling force to serotonin release. This review aims to place this mechanism into the larger context of ECC mechanotransduction.
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Affiliation(s)
- Arthur Beyder
- Enteric Neuroscience Program, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN, United States
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
- *Correspondence: Arthur Beyder
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30
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Asano T, Takenaga M. Adenosine A 2B Receptors: An Optional Target for the Management of Irritable Bowel Syndrome with Diarrhea? J Clin Med 2017; 6:jcm6110104. [PMID: 29099770 PMCID: PMC5704121 DOI: 10.3390/jcm6110104] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 10/31/2017] [Accepted: 11/02/2017] [Indexed: 12/12/2022] Open
Abstract
Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder, with the characteristic symptoms of chronic abdominal pain and altered bowel habits (diarrhea, constipation, or both). IBS is a highly prevalent condition, which negatively affects quality of life and is a significant burden on global healthcare costs. Although many pharmacological medicines have been proposed to treat IBS, including those targeting receptors, channels, and chemical mediators related to visceral hypersensitivity, successful pharmacotherapy for the disease has not been established. Visceral hypersensitivity plays an important role in IBS pathogenesis. Immune activation is observed in diarrhea-predominant patients with IBS and contributes to the development of visceral hypersensitivity. Adenosine is a chemical mediator that regulates many physiological processes, including inflammation and nociception. Among its receptors, the adenosine A2B receptor regulates intestinal secretion, motor function, and the immune response. We recently demonstrated that the adenosine A2B receptor is involved in visceral hypersensitivity in animal models of IBS. In this review, we discuss the possibility of the adenosine A2B receptor as a novel therapeutic target for IBS.
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Affiliation(s)
- Teita Asano
- Institute of Medical Science, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki 216-8512, Japan.
| | - Mitsuko Takenaga
- Institute of Medical Science, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki 216-8512, Japan.
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31
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Costello CM, Phillipsen MB, Hartmanis LM, Kwasnica MA, Chen V, Hackam D, Chang MW, Bentley WE, March JC. Microscale Bioreactors for in situ characterization of GI epithelial cell physiology. Sci Rep 2017; 7:12515. [PMID: 28970586 PMCID: PMC5624909 DOI: 10.1038/s41598-017-12984-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 09/14/2017] [Indexed: 02/08/2023] Open
Abstract
The development of in vitro artificial small intestines that realistically mimic in vivo systems will enable vast improvement of our understanding of the human gut and its impact on human health. Synthetic in vitro models can control specific parameters, including (but not limited to) cell types, fluid flow, nutrient profiles and gaseous exchange. They are also “open” systems, enabling access to chemical and physiological information. In this work, we demonstrate the importance of gut surface topography and fluid flow dynamics which are shown to impact epithelial cell growth, proliferation and intestinal cell function. We have constructed a small intestinal bioreactor using 3-D printing and polymeric scaffolds that mimic the 3-D topography of the intestine and its fluid flow. Our results indicate that TEER measurements, which are typically high in static 2-D Transwell apparatuses, is lower in the presence of liquid sheer and 3-D topography compared to a flat scaffold and static conditions. There was also increased cell proliferation and discovered localized regions of elevated apoptosis, specifically at the tips of the villi, where there is highest sheer. Similarly, glucose was actively transported (as opposed to passive) and at higher rates under flow.
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Affiliation(s)
- Cait M Costello
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, USA
| | - Mikkel B Phillipsen
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, USA
| | - Leonard M Hartmanis
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, USA
| | - Marek A Kwasnica
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, USA
| | - Victor Chen
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, USA
| | - David Hackam
- Division of Pediatric Surgery, Department of Surgery, Johns Hopkins University, Baltimore, USA
| | - Matthew W Chang
- Department of Biochemistry, Yong Loo Lin School of Medicine, NUS, Singapore, Singapore
| | - William E Bentley
- Institute for Biomedical Devices, University of Maryland, Maryland, USA
| | - John C March
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, USA.
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Liñán-Rico A, Ochoa-Cortes F, Zuleta-Alarcon A, Alhaj M, Tili E, Enneking J, Harzman A, Grants I, Bergese S, Christofi FL. UTP - Gated Signaling Pathways of 5-HT Release from BON Cells as a Model of Human Enterochromaffin Cells. Front Pharmacol 2017; 8:429. [PMID: 28751862 PMCID: PMC5508028 DOI: 10.3389/fphar.2017.00429] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 06/15/2017] [Indexed: 12/30/2022] Open
Abstract
Background: Enterochromaffin cells (EC) synthesize and release 5-HT and ATP to trigger or modulate gut neural reflexes and transmit information about visceral/pain sensation. Alterations in 5-HT signaling mechanisms may contribute to the pathogenesis of IBD or IBS, but the pharmacologic or molecular mechanisms modulating Ca2+-dependent 5-HT release are not understood. Previous studies indicated that purinergic signaling via ATP and ADP is an important mechanism in modulation of 5-HT release. However, EC cells also respond to UTP and UDP suggesting uridine triphosphate receptor and signaling pathways are involved as well. We tested the hypothesis that UTP is a regulator of 5-HT release in human EC cells. Methods: UTP signaling mechanisms were studied in BON cells, a human EC model, using Fluo-4/Ca2+imaging, patch-clamp, pharmacological analysis, immunohistochemistry, western blots and qPCR. 5-HT release was monitored in BON or EC isolated from human gut surgical specimens (hEC). Results: UTP, UTPγS, UDP or ATP induced Ca2+oscillations in BON. UTP evoked a biphasic concentration-dependent Ca2+response. Cells responded in the order of UTP, ATP > UTPγS > UDP >> MRS2768, BzATP, α,β-MeATP > MRS2365, MRS2690, and NF546. Different proportions of cells activated by UTP and ATP also responded to UTPγS (P2Y4, 50% cells), UDP (P2Y6, 30%), UTPγS and UDP (14%) or MRS2768 (<3%). UTP Ca2+responses were blocked with inhibitors of PLC, IP3R, SERCA Ca2+pump, La3+sensitive Ca2+channels or chelation of intracellular free Ca2+ by BAPTA/AM. Inhibitors of L-type, TRPC, ryanodine-Ca2+pools, PI3-Kinase, PKC or SRC-Kinase had no effect. UTP stimulated voltage-sensitive Ca2+currents (ICa), Vm-depolarization and inhibited IK (not IA) currents. An IKv7.2/7.3 K+ channel blocker XE-991 mimicked UTP-induced Vm-depolarization and blocked UTP-responses. XE-991 blocked IK and UTP caused further reduction. La3+ or PLC inhibitors blocked UTP depolarization; PKC inhibitors, thapsigargin or zero Ca2+buffer did not. UTP stimulated 5-HT release in hEC expressing TPH1, 5-HT, P2Y4/P2Y6R. Zero-Ca2+buffer augmented Ca2+responses and 5-HT release. Conclusion: UTP activates a predominant P2Y4R pathway to trigger Ca2+oscillations via internal Ca2+mobilization through a PLC/IP3/IP3R/SERCA Ca2+signaling pathway to stimulate 5-HT release; Ca2+influx is inhibitory. UTP-induced Vm-depolarization depends on PLC signaling and an unidentified K channel (which appears independent of Ca2+oscillations or Ica/VOCC). UTP-gated signaling pathways triggered by activation of P2Y4R stimulate 5-HT release.
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Affiliation(s)
- Andromeda Liñán-Rico
- Department of Anesthesiology, The Wexner Medical Center at The Ohio State University, ColumbusOH, United States
| | - Fernando Ochoa-Cortes
- Department of Anesthesiology, The Wexner Medical Center at The Ohio State University, ColumbusOH, United States
| | - Alix Zuleta-Alarcon
- Department of Anesthesiology, The Wexner Medical Center at The Ohio State University, ColumbusOH, United States
| | - Mazin Alhaj
- Department of Anesthesiology, The Wexner Medical Center at The Ohio State University, ColumbusOH, United States
| | - Esmerina Tili
- Department of Anesthesiology, The Wexner Medical Center at The Ohio State University, ColumbusOH, United States
- Molecular Virology, Immunology and Medical Genetics, The Wexner Medical Center at The Ohio State University, ColumbusOH, United States
| | - Josh Enneking
- Department of Anesthesiology, The Wexner Medical Center at The Ohio State University, ColumbusOH, United States
| | - Alan Harzman
- Department of Surgery, The Wexner Medical Center at The Ohio State University, ColumbusOH, United States
| | - Iveta Grants
- Department of Anesthesiology, The Wexner Medical Center at The Ohio State University, ColumbusOH, United States
| | - Sergio Bergese
- Department of Anesthesiology, The Wexner Medical Center at The Ohio State University, ColumbusOH, United States
| | - Fievos L. Christofi
- Department of Anesthesiology, The Wexner Medical Center at The Ohio State University, ColumbusOH, United States
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Martin AM, Young RL, Leong L, Rogers GB, Spencer NJ, Jessup CF, Keating DJ. The Diverse Metabolic Roles of Peripheral Serotonin. Endocrinology 2017; 158:1049-1063. [PMID: 28323941 DOI: 10.1210/en.2016-1839] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2016] [Accepted: 02/23/2017] [Indexed: 02/07/2023]
Abstract
Serotonin (5-hydroxytryptamine or 5-HT) is a multifunctional bioamine with important signaling roles in a range of physiological pathways. Almost all of the 5-HT in our bodies is synthesized in specialized enteroendocrine cells within the gastrointestinal (GI) mucosa called enterochromaffin (EC) cells. These cells provide all of our circulating 5-HT. We have long appreciated the important contributions of 5-HT within the gut, including its role in modulating GI motility. However, evidence of the physiological and clinical significance of gut-derived 5-HT outside of the gut has recently emerged, implicating 5-HT in regulation of glucose homeostasis, lipid metabolism, bone density, and diseases associated with metabolic syndrome, such as obesity and type 2 diabetes. Although a new picture has developed in the last decade regarding the various metabolic roles of peripheral serotonin, so too has our understanding of the physiology of EC cells. Given that they are scattered throughout the lining of the GI tract within the epithelial cell layer, these cells are typically difficult to study. Advances in isolation procedures now allow the study of pure EC-cell cultures and single cells, enabling studies of EC-cell physiology to occur. EC cells are sensory cells that are capable of integrating cues from ingested nutrients, the enteric nervous system, and the gut microbiome. Thus, levels of peripheral 5-HT can be modulated by a multitude of factors, resulting in both local and systemic effects for the regulation of a raft of physiological pathways related to metabolism and obesity.
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Affiliation(s)
- Alyce M Martin
- Discipline of Human Physiology and Centre for Neuroscience, Flinders University of South Australia, Adelaide 5042, Australia
| | - Richard L Young
- Nutrition and Metabolism, South Australian Health and Medical Research Institute (SAHMRI), Adelaide 5001, Australia
- Adelaide Medical School, University of Adelaide, Adelaide 5005, Australia
| | - Lex Leong
- Infection and Immunity, SAHMRI, Adelaide 5001, Australia
- SAHMRI Microbiome Research Laboratory, School of Medicine, Flinders University of South Australia, Adelaide 5042, Australia
| | - Geraint B Rogers
- Infection and Immunity, SAHMRI, Adelaide 5001, Australia
- SAHMRI Microbiome Research Laboratory, School of Medicine, Flinders University of South Australia, Adelaide 5042, Australia
| | - Nick J Spencer
- Discipline of Human Physiology and Centre for Neuroscience, Flinders University of South Australia, Adelaide 5042, Australia
| | - Claire F Jessup
- Adelaide Medical School, University of Adelaide, Adelaide 5005, Australia
- Discipline of Anatomy and Histology, Flinders University of South Australia, Adelaide 5042, Australia
| | - Damien J Keating
- Discipline of Human Physiology and Centre for Neuroscience, Flinders University of South Australia, Adelaide 5042, Australia
- Nutrition and Metabolism, South Australian Health and Medical Research Institute (SAHMRI), Adelaide 5001, Australia
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Alcaino C, Knutson K, Gottlieb PA, Farrugia G, Beyder A. Mechanosensitive ion channel Piezo2 is inhibited by D-GsMTx4. Channels (Austin) 2017; 11:245-253. [PMID: 28085630 DOI: 10.1080/19336950.2017.1279370] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Enterochromaffin (EC) cells are the primary mechanosensors of the gastrointestinal (GI) epithelium. In response to mechanical stimuliEC cells release serotonin (5-hydroxytryptamine; 5-HT). The molecular details ofEC cell mechanosensitivity are poorly understood. Recently, our group found that human and mouseEC cells express the mechanosensitive ion channel Piezo2. The mechanosensitive currents in a humanEC cell model QGP-1 were blocked by the mechanosensitive channel blocker D-GsMTx4. In the present study we aimed to characterize the effects of the mechanosensitive ion channel inhibitor spider peptide D-GsMTx4 on the mechanically stimulated currents from both QGP-1 and human Piezo2 transfected HEK-293 cells. We found co-localization of 5-HT and Piezo2 in QGP-1 cells by immunohistochemistry. QGP-1 mechanosensitive currents had biophysical properties similar to dose-dependently Piezo2 and were inhibited by D-GsMTx4. In response to direct displacement of cell membranes, human Piezo2 transiently expressed in HEK-293 cells produced robust rapidly activating and inactivating inward currents. D-GsMTx4 reversibly and dose-dependently inhibited both the potency and efficacy of Piezo2 currents in response to mechanical force. Our data demonstrate an effective inhibition of Piezo2 mechanosensitive currents by the spider peptide D-GsMTx4.
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Affiliation(s)
- Constanza Alcaino
- a Department of Physiology & Biomedical Engineering, Enteric Neuroscience Program, Division of Gastroenterology & Hepatology , Mayo Clinic , Rochester , MN , USA
| | - Kaitlyn Knutson
- a Department of Physiology & Biomedical Engineering, Enteric Neuroscience Program, Division of Gastroenterology & Hepatology , Mayo Clinic , Rochester , MN , USA
| | - Philip A Gottlieb
- b Department of Physiology and Biophysics, Center for Single Molecule Biophysics , State University of New York , Buffalo , NY , USA
| | - Gianrico Farrugia
- b Department of Physiology and Biophysics, Center for Single Molecule Biophysics , State University of New York , Buffalo , NY , USA
| | - Arthur Beyder
- a Department of Physiology & Biomedical Engineering, Enteric Neuroscience Program, Division of Gastroenterology & Hepatology , Mayo Clinic , Rochester , MN , USA
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Alcaino C, Farrugia G, Beyder A. Mechanosensitive Piezo Channels in the Gastrointestinal Tract. CURRENT TOPICS IN MEMBRANES 2017; 79:219-244. [PMID: 28728818 PMCID: PMC5606247 DOI: 10.1016/bs.ctm.2016.11.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Sensation of mechanical forces is critical for normal function of the gastrointestinal (GI) tract and abnormalities in mechanosensation are linked to GI pathologies. In the GI tract there are several mechanosensitive cell types-epithelial enterochromaffin cells, intrinsic and extrinsic enteric neurons, smooth muscle cells and interstitial cells of Cajal. These cells use mechanosensitive ion channels that respond to mechanical forces by altering transmembrane ionic currents in a process called mechanoelectrical coupling. Several mechanosensitive ionic conductances have been identified in the mechanosensory GI cells, ranging from mechanosensitive voltage-gated sodium and calcium channels to the mechanogated ion channels, such as the two-pore domain potassium channels K2P (TREK-1) and nonselective cation channels from the transient receptor potential family. The recently discovered Piezo channels are increasingly recognized as significant contributors to cellular mechanosensitivity. Piezo1 and Piezo2 are nonselective cationic ion channels that are directly activated by mechanical forces and have well-defined biophysical and pharmacologic properties. The role of Piezo channels in the GI epithelium is currently under investigation and their role in the smooth muscle syncytium and enteric neurons is still not known. In this review, we outline the current state of knowledge on mechanosensitive ion channels in the GI tract, with a focus on the known and potential functions of the Piezo channels.
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Affiliation(s)
- C Alcaino
- Mayo Clinic College of Medicine, Rochester, MN, United States
| | - G Farrugia
- Mayo Clinic College of Medicine, Rochester, MN, United States
| | - A Beyder
- Mayo Clinic College of Medicine, Rochester, MN, United States
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36
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Linan-Rico A, Ochoa-Cortes F, Beyder A, Soghomonyan S, Zuleta-Alarcon A, Coppola V, Christofi FL. Mechanosensory Signaling in Enterochromaffin Cells and 5-HT Release: Potential Implications for Gut Inflammation. Front Neurosci 2016; 10:564. [PMID: 28066160 PMCID: PMC5165017 DOI: 10.3389/fnins.2016.00564] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 11/22/2016] [Indexed: 12/12/2022] Open
Abstract
Enterochromaffin (EC) cells synthesize 95% of the body 5-HT and release 5-HT in response to mechanical or chemical stimulation. EC cell 5-HT has physiological effects on gut motility, secretion and visceral sensation. Abnormal regulation of 5-HT occurs in gastrointestinal disorders and Inflammatory Bowel Diseases (IBD) where 5-HT may represent a key player in the pathogenesis of intestinal inflammation. The focus of this review is on mechanism(s) involved in EC cell "mechanosensation" and critical gaps in our knowledge for future research. Much of our knowledge and concepts are from a human BON cell model of EC, although more recent work has included other cell lines, native EC cells from mouse and human and intact mucosa. EC cells are "mechanosensors" that respond to physical forces generated during peristaltic activity by translating the mechanical stimulus (MS) into an intracellular biochemical response leading to 5-HT and ATP release. The emerging picture of mechanosensation includes Piezo 2 channels, caveolin-rich microdomains, and tight regulation of 5-HT release by purines. The "purinergic hypothesis" is that MS releases purines to act in an autocrine/paracrine manner to activate excitatory (P2Y1, P2Y4, P2Y6, and A2A/A2B) or inhibitory (P2Y12, A1, and A3) receptors to regulate 5-HT release. MS activates a P2Y1/Gαq/PLC/IP3-IP3R/SERCA Ca2+signaling pathway, an A2A/A2B-Gs/AC/cAMP-PKA signaling pathway, an ATP-gated P2X3 channel, and an inhibitory P2Y12-Gi/o/AC-cAMP pathway. In human IBD, P2X3 is down regulated and A2B is up regulated in EC cells, but the pathophysiological consequences of abnormal mechanosensory or purinergic 5-HT signaling remain unknown. EC cell mechanosensation remains poorly understood.
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Affiliation(s)
- Andromeda Linan-Rico
- Department of Anesthesiology, Wexner Medical Center at Ohio State UniversityColumbus, OH, USA; CONACYT-Centro Universitario de Investigaciones Biomedicas, University of ColimaColima, Mexico
| | - Fernando Ochoa-Cortes
- Department of Anesthesiology, Wexner Medical Center at Ohio State University Columbus, OH, USA
| | - Arthur Beyder
- Enteric Neuroscience Program, Division of Gastroenterology and Hepatology, Department of Physiology and Biomedical Engineering, Mayo Clinic Rochester, MN, USA
| | - Suren Soghomonyan
- Department of Anesthesiology, Wexner Medical Center at Ohio State University Columbus, OH, USA
| | - Alix Zuleta-Alarcon
- Department of Anesthesiology, Wexner Medical Center at Ohio State University Columbus, OH, USA
| | - Vincenzo Coppola
- SBS-Cancer Biology and Genetics, Ohio State University Columbus, OH, USA
| | - Fievos L Christofi
- Department of Anesthesiology, Wexner Medical Center at Ohio State University Columbus, OH, USA
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Kalbe B, Schlimm M, Mohrhardt J, Scholz P, Jansen F, Hatt H, Osterloh S. Helional induces Ca2+ decrease and serotonin secretion of QGP-1 cells via a PKG-mediated pathway. J Mol Endocrinol 2016; 57:201-10. [PMID: 27553203 DOI: 10.1530/jme-16-0063] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 08/22/2016] [Indexed: 12/30/2022]
Abstract
The secretion, motility and transport by intestinal tissues are regulated among others by specialized neuroendocrine cells, the so-called enterochromaffin (EC) cells. These cells detect different luminal stimuli, such as mechanical stimuli, fatty acids, glucose and distinct chemosensory substances. The EC cells react to the changes in their environment through the release of transmitter molecules, most importantly serotonin, to mediate the corresponding physiological response. However, little is known about the molecular targets of the chemical stimuli delivered from consumed food, spices and cosmetics within EC cells. In this study, we evaluated the expression of the olfactory receptor (OR) 2J3 in the human pancreatic EC cell line QGP-1 at the mRNA and protein levels. Using ratiofluorometric Ca(2+) imaging experiments, we demonstrated that the OR2J3-specific agonist helional induces a transient dose-dependent decrease in the intracellular Ca(2+) levels. This Ca(2+) decrease is mediated by protein kinase G (PKG) on the basis that the specific pharmacological inhibition of PKG with Rp-8-pCPT-cGMPS abolished the helional-induced Ca(2+) response. Furthermore, stimulation of QGP-1 cells with helional caused a dose-dependent release of serotonin that was comparable with the release induced by the application of a direct PKG activator (8-bromo-cGMP). Taken together, our results demonstrate that luminal odorants can be detected by specific ORs in QGP-1 cells and thus cause the directed release of serotonin and a PKG-dependent decrease in intracellular Ca(2.)
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Affiliation(s)
- Benjamin Kalbe
- Department of Cell PhysiologyRuhr-University Bochum, Bochum, Germany
| | - Marian Schlimm
- Department of Cell PhysiologyRuhr-University Bochum, Bochum, Germany
| | - Julia Mohrhardt
- Department of ChemosensationInstitute for Biology II, RWTH Aachen University, Aachen, Germany
| | - Paul Scholz
- Department of Cell PhysiologyRuhr-University Bochum, Bochum, Germany
| | - Fabian Jansen
- Department of Cell PhysiologyRuhr-University Bochum, Bochum, Germany
| | - Hanns Hatt
- Department of Cell PhysiologyRuhr-University Bochum, Bochum, Germany
| | - Sabrina Osterloh
- Department of Cell PhysiologyRuhr-University Bochum, Bochum, Germany
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Jin DC, Cao HL, Xu MQ, Wang SN, Wang YM, Yan F, Wang BM. Regulation of the serotonin transporter in the pathogenesis of irritable bowel syndrome. World J Gastroenterol 2016; 22:8137-8148. [PMID: 27688655 PMCID: PMC5037082 DOI: 10.3748/wjg.v22.i36.8137] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Revised: 05/28/2016] [Accepted: 06/15/2016] [Indexed: 02/06/2023] Open
Abstract
Serotonin (5-HT) and the serotonin transporter (SERT) have earned a tremendous amount of attention regarding the pathogenesis of irritable bowel syndrome (IBS). Considering that enteric 5-HT is responsible for the secretion, motility and perception of the bowel, the involvement of altered enteric 5-HT metabolism in the pathogenesis of IBS has been elucidated. Higher 5-HT availability is commonly associated with depressed SERT mRNA in patients with IBS compared with healthy controls. The expression difference of SERT between IBS patients and healthy controls might suggest that SERT plays an essential role in IBS pathogenesis, and SERT was expected to be a novel therapeutic target for IBS. Progress in this area has begun to illuminate the complex regulatory mechanisms of SERT in the etiology of IBS. In this article, current insights regarding the regulation of SERT in IBS are provided, including aspects of SERT gene polymorphisms, microRNAs, immunity and inflammation, gut microbiota, growth factors, among others. Potential SERT-directed therapies for IBS are also described. The potential regulators of SERT are of clinical importance and are important for better understanding IBS pathophysiology and therapeutic strategies.
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Wang F, Knutson K, Alcaino C, Linden DR, Gibbons SJ, Kashyap P, Grover M, Oeckler R, Gottlieb PA, Li HJ, Leiter AB, Farrugia G, Beyder A. Mechanosensitive ion channel Piezo2 is important for enterochromaffin cell response to mechanical forces. J Physiol 2016; 595:79-91. [PMID: 27392819 DOI: 10.1113/jp272718] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 06/29/2016] [Indexed: 12/31/2022] Open
Abstract
KEY POINTS The gastrointestinal epithelial enterochromaffin (EC) cell synthesizes the vast majority of the body's serotonin. As a specialized mechanosensor, the EC cell releases this serotonin in response to mechanical forces. However, the molecular mechanism of EC cell mechanotransduction is unknown. In the present study, we show, for the first time, that the mechanosensitive ion channel Piezo2 is specifically expressed by the human and mouse EC cells. Activation of Piezo2 by mechanical forces results in a characteristic ionic current, the release of serotonin and stimulation of gastrointestinal secretion. Piezo2 inhibition by drugs or molecular knockdown decreases mechanosensitive currents, serotonin release and downstream physiological effects. The results of the present study suggest that the mechanosensitive ion channel Piezo2 is specifically expressed by the EC cells of the human and mouse small bowel and that it is important for EC cell mechanotransduction. ABSTRACT The enterochromaffin (EC) cell in the gastrointestinal (GI) epithelium is the source of nearly all systemic serotonin (5-hydroxytryptamine; 5-HT), which is an important neurotransmitter and endocrine, autocrine and paracrine hormone. The EC cell is a specialized mechanosensor, and it is well known that it releases 5-HT in response to mechanical forces. However, the EC cell mechanotransduction mechanism is unknown. The present study aimed to determine whether Piezo2 is involved in EC cell mechanosensation. Piezo2 mRNA was expressed in human jejunum and mouse mucosa from all segments of the small bowel. Piezo2 immunoreactivity localized specifically within EC cells of human and mouse small bowel epithelium. The EC cell model released 5-HT in response to stretch, and had Piezo2 mRNA and protein, as well as a mechanically-sensitive inward non-selective cation current characteristic of Piezo2. Both inward currents and 5-HT release were inhibited by Piezo2 small interfering RNA and antagonists (Gd3+ and D-GsMTx4). Jejunum mucosal pressure increased 5-HT release and short-circuit current via submucosal 5-HT3 and 5-HT4 receptors. Pressure-induced secretion was inhibited by the mechanosensitive ion channel antagonists gadolinium, ruthenium red and D-GsMTx4. We conclude that the EC cells in the human and mouse small bowel GI epithelium selectively express the mechanosensitive ion channel Piezo2, and also that activation of Piezo2 by force leads to inward currents, 5-HT release and an increase in mucosal secretion. Therefore, Piezo2 is critical to EC cell mechanosensitivity and downstream physiological effects.
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Affiliation(s)
- Fan Wang
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Departments of Medicine and Physiology & Biomedical Engineering, Mayo Clinic, 200 First Street SW, Rochester, MN, USA.,Department of Gastroenterology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, 300 Yanchang Middle Road, Shanghai, PR China
| | - Kaitlyn Knutson
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Departments of Medicine and Physiology & Biomedical Engineering, Mayo Clinic, 200 First Street SW, Rochester, MN, USA
| | - Constanza Alcaino
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Departments of Medicine and Physiology & Biomedical Engineering, Mayo Clinic, 200 First Street SW, Rochester, MN, USA
| | - David R Linden
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Departments of Medicine and Physiology & Biomedical Engineering, Mayo Clinic, 200 First Street SW, Rochester, MN, USA
| | - Simon J Gibbons
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Departments of Medicine and Physiology & Biomedical Engineering, Mayo Clinic, 200 First Street SW, Rochester, MN, USA
| | - Purna Kashyap
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Departments of Medicine and Physiology & Biomedical Engineering, Mayo Clinic, 200 First Street SW, Rochester, MN, USA
| | - Madhusudan Grover
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Departments of Medicine and Physiology & Biomedical Engineering, Mayo Clinic, 200 First Street SW, Rochester, MN, USA
| | - Richard Oeckler
- Division of Pulmonary and Critical Care, Departments of Medicine and Physiology & Biomedical Engineering, Mayo Clinic, 200 First Street SW, Rochester, MN, USA
| | - Philip A Gottlieb
- Department of Physiology and Biophysics, State University of New York at Buffalo, 3435 Main Street, Buffalo, NY, USA
| | - Hui Joyce Li
- Department of Medicine, Division of Gastroenterology, University of Massachusetts Medical School, 55 N Lake Ave, Worcester, MA, USA
| | - Andrew B Leiter
- Department of Medicine, Division of Gastroenterology, University of Massachusetts Medical School, 55 N Lake Ave, Worcester, MA, USA
| | - Gianrico Farrugia
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Departments of Medicine and Physiology & Biomedical Engineering, Mayo Clinic, 200 First Street SW, Rochester, MN, USA
| | - Arthur Beyder
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Departments of Medicine and Physiology & Biomedical Engineering, Mayo Clinic, 200 First Street SW, Rochester, MN, USA
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Margolis KG, Gershon MD. Enteric Neuronal Regulation of Intestinal Inflammation. Trends Neurosci 2016; 39:614-624. [PMID: 27450201 DOI: 10.1016/j.tins.2016.06.007] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 06/24/2016] [Accepted: 06/27/2016] [Indexed: 02/07/2023]
Abstract
Recent research has highlighted the importance of the two-way interaction between the nervous and immune systems. This interaction is particularly important in the bowel because of the unique properties of this organ. The lumen of the gut is lined by a very large but remarkably thin surface that separates the body from the enteric microbiome. Immune defenses against microbial invasion are thus well developed and neuroimmune interactions are important in regulating and integrating these defenses. Important concepts in the phylogeny of neuroimmunity, enteric neuronal and glial regulation of immunity, changes that occur in the enteric nervous system during inflammation, the fundamental role of serotonin (5-HT) in enteric neuroimmune mechanisms, and future perspectives are reviewed.
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Affiliation(s)
- Kara Gross Margolis
- Department of Pediatrics, Columbia University College of Physicians and Surgeons, 620 West 168th Street, New York, NY 10032, USA
| | - Michael D Gershon
- Department of Pathology and Cell Biology, Columbia University College of Physicians and Surgeons, 650 West 168th Street, New York, NY 10032, USA.
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Terry N, Margolis KG. Serotonergic Mechanisms Regulating the GI Tract: Experimental Evidence and Therapeutic Relevance. Handb Exp Pharmacol 2016; 239:319-342. [PMID: 28035530 DOI: 10.1007/164_2016_103] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Serotonin (5-hydroxytryptamine; 5-HT) is best known as a neurotransmitter critical for central nervous system (CNS) development and function. 95% of the body's serotonin, however, is produced in the intestine where it has been increasingly recognized for its hormonal, autocrine, paracrine, and endocrine actions. This chapter provides the most current knowledge of the critical autocrine and paracrine roles of 5-HT in intestinal motility and inflammation as well as its function as a hormone in osteocyte homeostasis. Therapeutic applications in each of these areas are also discussed.
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Affiliation(s)
- Natalie Terry
- Division of Pediatric Gastroenterology, Children's Hospital of Philadelphia, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Kara Gross Margolis
- Division of Pediatric Gastroenterology, Department of Pediatrics, Morgan Stanley Children's Hospital, Columbia University Medical Center, New York, NY, USA.
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France M, Skorich E, Kadrofske M, Swain GM, Galligan JJ. Sex-related differences in small intestinal transit and serotonin dynamics in high-fat-diet-induced obesity in mice. Exp Physiol 2015; 101:81-99. [PMID: 26381722 DOI: 10.1113/ep085427] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2015] [Accepted: 09/15/2015] [Indexed: 12/17/2022]
Abstract
Obesity alters gastrointestinal (GI) motility and 5-HT signalling. Altered 5-HT signalling disrupts control of GI motility. Levels of extracellular 5-HT depend on enterochromaffin (EC) cell release and serotonin transporter (SERT) uptake. We assessed GI transit and 5-HT signalling in the jejunum of normal and obese mice. Male and female mice were fed a control diet (CD; 10% of kilocalories as fat) or a high-fat diet (HFD; 60% of kilocalories as fat). Gastrointestinal transit was increased in male HFD-fed and female CD-fed compared with male CD-fed mice. The 5-HT3 receptor blocker, alosetron, increased gastric emptying in male CD-fed mice, but decreased transit in female CD-fed mice. The 5-HT-induced jejunal longitudinal muscle contractions in vitro were similar in all mice. In contrast to male CD-fed mice, 5-HT uptake (measured using continuous amperometry in vitro) in male HFD-fed mice was fluoxetine insensitive, yet sensitive to cocaine and the dopamine transporter (DAT) blocker GBR 12909. Immunoreactivity for DAT was present in the mucosa, and protein levels were greater in male HFD-fed compared with CD-fed mice. Extracellular 5-HT and mucosal 5-hydroxyindolacetic acid (5-HT metabolite) were similar in male HFD-fed compared with CD-fed mice. 5-Hydroxytryptamine uptake was fluoxetine sensitive in all females. Greater SERT protein, decreased extracellular 5-HT and greater mucosal 5-hydroxyindolacetic acid were observed in female HFD-fed compared with CD-fed mice. Mucosal 5-HT and EC cell numbers were similar in CD-fed and HFD-fed mice of both sexes; female 5-HT and EC cell numbers were increased compared with males. The HFD did not alter plasma sex hormone levels in any mice. Overall, obesity alters GI transit and 5-HT signalling in a sex-dependent manner.
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Affiliation(s)
- Marion France
- Neuroscience Program, Michigan State University, East Lansing, MI, USA
| | - Emmalee Skorich
- Neuroscience Program, Michigan State University, East Lansing, MI, USA
| | - Mark Kadrofske
- Department of Pediatrics and Human Development, Michigan State University, East Lansing, MI, USA
| | - Greg M Swain
- Neuroscience Program, Michigan State University, East Lansing, MI, USA.,Department of Chemistry, Michigan State University, East Lansing, MI, USA
| | - James J Galligan
- Neuroscience Program, Michigan State University, East Lansing, MI, USA.,Department of Pharmacology & Toxicology, Michigan State University, East Lansing, MI, USA
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Guo CC, Deng Y, Ye H, Zhu YZ, Zheng XB. Role of MAPK signaling pathways in inflammatory bowel disease. Shijie Huaren Xiaohua Zazhi 2015; 23:229-235. [DOI: 10.11569/wcjd.v23.i2.229] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Mitogen-activated protein kinases (MAPKs) are a group of highly conserved serine protein kinases which are distributed in the cytoplasm. MAPK signal transduction pathways play a major role in inflammatory reactions and have a close relation with inflammatory bowel disease (IBD). They could be involved in the regulation of inflammatory mediators as well as IBD-associated genes. This paper reviews the role of MAPK signaling pathways in the pathogenesis of IBD, aiming at providing a new method for the treatment of IBD.
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Kidd M, Modlin IM, Bodei L, Drozdov I. Decoding the Molecular and Mutational Ambiguities of Gastroenteropancreatic Neuroendocrine Neoplasm Pathobiology. Cell Mol Gastroenterol Hepatol 2015; 1:131-153. [PMID: 28210673 PMCID: PMC5301133 DOI: 10.1016/j.jcmgh.2014.12.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 12/19/2014] [Indexed: 02/08/2023]
Abstract
Gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN), considered a heterogeneous neoplasia, exhibit ill-defined pathobiology and protean symptomatology and are ubiquitous in location. They are difficult to diagnose, challenging to manage, and outcome depends on cell type, secretory product, histopathologic grading, and organ of origin. A morphologic and molecular genomic review of these lesions highlights tumor characteristics that can be used clinically, such as somatostatin-receptor expression, and confirms features that set them outside the standard neoplasia paradigm. Their unique pathobiology is useful for developing diagnostics using somatostatin-receptor targeted imaging or uptake of radiolabeled amino acids specific to secretory products or metabolism. Therapy has evolved via targeting of protein kinase B signaling or somatostatin receptors with drugs or isotopes (peptide-receptor radiotherapy). With DNA sequencing, rarely identified activating mutations confirm that tumor suppressor genes are relevant. Genomic approaches focusing on cancer-associated genes and signaling pathways likely will remain uninformative. Their uniquely dissimilar molecular profiles mean individual tumors are unlikely to be easily or uniformly targeted by therapeutics currently linked to standard cancer genetic paradigms. The prevalence of menin mutations in pancreatic NEN and P27KIP1 mutations in small intestinal NEN represents initial steps to identifying a regulatory commonality in GEP-NEN. Transcriptional profiling and network-based analyses may define the cellular toolkit. Multianalyte diagnostic tools facilitate more accurate molecular pathologic delineations of NEN for assessing prognosis and identifying strategies for individualized patient treatment. GEP-NEN remain unique, poorly understood entities, and insight into their pathobiology and molecular mechanisms of growth and metastasis will help identify the diagnostic and therapeutic weaknesses of this neoplasia.
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Key Words
- 5-HT, serotonin, 5-hydroxytryptamine
- Akt, protein kinase B
- BRAF, gene encoding serine/threonine-protein kinase B-Raf
- Blood
- CGH, comparative genomic hybridization
- CREB, cAMP response element-binding protein
- Carcinoid
- CgA, chromogranin A
- D cell, somatostatin
- DAG, diacylglycerol
- EC, enterochromaffin
- ECL, enterochromaffin-like
- EGFR, epidermal growth factor receptor
- ERK, extracellular-signal-regulated kinase
- G cell, gastrin
- GABA, γ-aminobutyric acid
- GEP-NEN, gastroenteropancreatic neuroendocrine neoplasms
- GPCR, G-protein coupled receptor
- Gastroenteropancreatic Neuroendocrine Neoplasms
- IGF-I, insulin-like growth factor-I
- ISG, immature secretory vesicles
- Ki-67
- LOH, loss of heterozygosity
- MAPK, mitogen-activated protein kinase
- MEN-1/MEN1, multiple endocrine neoplasia type 1
- MSI, microsatellite instability
- MTA, metastasis associated-1
- NEN, neuroendocrine neoplasms
- NFκB, nuclear factor κB
- PET, positron emission tomography
- PI3, phosphoinositide-3
- PI3K, phosphoinositide-3 kinase
- PKA, protein kinase A
- PKC, protein kinase C
- PTEN, phosphatase and tensin homolog deleted on chromosome 10
- Proliferation
- SD-208, 2-(5-chloro-2-fluorophenyl)-4-[(4-pyridyl)amino]p-teridine
- SNV, single-nucleotide variant
- SSA, somatostatin analog
- SST, somatostatin
- Somatostatin
- TGF, transforming growth factor
- TGN, trans-Golgi network
- TSC2, tuberous sclerosis complex 2 (tuberin)
- Transcriptome
- VMAT, vesicular monoamine transporters
- X/A-like cells, ghrelin
- cAMP, adenosine 3′,5′-cyclic monophosphate
- mTOR, mammalian target of rapamycin
- miR/miRNA, micro-RNA
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Affiliation(s)
| | - Irvin M. Modlin
- Correspondence Address correspondence to: Irvin M. Modlin, MD, PhD, The Gnostic Consortium, Wren Laboratories, 35 NE Industrial Road, Branford, Connecticut, 06405.
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Nishida K, Dohi Y, Yamanaka Y, Miyata A, Tsukamoto K, Yabu M, Ohishi A, Nagasawa K. Expression of adenosine A2b receptor in rat type II and III taste cells. Histochem Cell Biol 2013; 141:499-506. [PMID: 24327108 DOI: 10.1007/s00418-013-1171-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/26/2013] [Indexed: 10/25/2022]
Abstract
We previously demonstrated that equilibrative nucleoside transporter 1 was expressed in taste cells, suggesting the existence of an adenosine signaling system, but whether or not the expression of an adenosine receptor occurs in rat taste buds remains unknown. Therefore, we examined the expression profiles of adenosine receptors and evaluated their functionality in rat circumvallate papillae. Among adenosine receptors, the mRNA for an adenosine A2b receptor (A2bR) was expressed by the rat circumvallate papillae, and its expression level was significantly greater in the circumvallate papillae than in the non-taste lingual epithelium. A2bR-immunoreactivity was detected primarily in type II taste cells, and partial, but significant expression was also observed in type III ones, but there was no immunoreactivity in type I ones. The cAMP generation in isolated epithelium containing taste buds treated with 500 μM adenosine or 10 μM BAY60-6583 was significantly increased compared to in the controls. These findings suggest that adenosine plays a role in signaling transmission via A2bR between taste cells in rats.
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Affiliation(s)
- Kentaro Nishida
- Department of Environmental Biochemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto, 607-8414, Japan
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Samsel A, Seneff S. Glyphosate, pathways to modern diseases II: Celiac sprue and gluten intolerance. Interdiscip Toxicol 2013; 6:159-84. [PMID: 24678255 PMCID: PMC3945755 DOI: 10.2478/intox-2013-0026] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 11/10/2013] [Accepted: 11/12/2013] [Indexed: 12/20/2022] Open
Abstract
Celiac disease, and, more generally, gluten intolerance, is a growing problem worldwide, but especially in North America and Europe, where an estimated 5% of the population now suffers from it. Symptoms include nausea, diarrhea, skin rashes, macrocytic anemia and depression. It is a multifactorial disease associated with numerous nutritional deficiencies as well as reproductive issues and increased risk to thyroid disease, kidney failure and cancer. Here, we propose that glyphosate, the active ingredient in the herbicide, Roundup(®), is the most important causal factor in this epidemic. Fish exposed to glyphosate develop digestive problems that are reminiscent of celiac disease. Celiac disease is associated with imbalances in gut bacteria that can be fully explained by the known effects of glyphosate on gut bacteria. Characteristics of celiac disease point to impairment in many cytochrome P450 enzymes, which are involved with detoxifying environmental toxins, activating vitamin D3, catabolizing vitamin A, and maintaining bile acid production and sulfate supplies to the gut. Glyphosate is known to inhibit cytochrome P450 enzymes. Deficiencies in iron, cobalt, molybdenum, copper and other rare metals associated with celiac disease can be attributed to glyphosate's strong ability to chelate these elements. Deficiencies in tryptophan, tyrosine, methionine and selenomethionine associated with celiac disease match glyphosate's known depletion of these amino acids. Celiac disease patients have an increased risk to non-Hodgkin's lymphoma, which has also been implicated in glyphosate exposure. Reproductive issues associated with celiac disease, such as infertility, miscarriages, and birth defects, can also be explained by glyphosate. Glyphosate residues in wheat and other crops are likely increasing recently due to the growing practice of crop desiccation just prior to the harvest. We argue that the practice of "ripening" sugar cane with glyphosate may explain the recent surge in kidney failure among agricultural workers in Central America. We conclude with a plea to governments to reconsider policies regarding the safety of glyphosate residues in foods.
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Affiliation(s)
- Anthony Samsel
- Independent Scientist and Consultant, Deerfield, NH 03037, USA
| | - Stephanie Seneff
- Computer Science and Artificial Intelligence Laboratory, MIT, Cambridge, MA, USA
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Giovinazzo F, Schimmack S, Svejda B, Alaimo D, Pfragner R, Modlin I, Kidd M. Chromogranin A and its fragments as regulators of small intestinal neuroendocrine neoplasm proliferation. PLoS One 2013; 8:e81111. [PMID: 24260544 PMCID: PMC3834250 DOI: 10.1371/journal.pone.0081111] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 10/17/2013] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION Chromogranin A is a neuroendocrine secretory product and its loss is a feature of malignant NEN de-differentiation. We hypothesized that chromogranin A fragments were differentially expressed during NEN metastasis and played a role in the regulation of NEN proliferation. METHODS Chromogranin A mRNA (PCR) and protein (ELISA/western blot) were studied in 10 normal human mucosa, 5 enterochromaffin cell preparations, 26 small intestinal NEN primaries and 9 liver metastases. Cell viability (WST-1 assay), proliferation (bromodeoxyuridine ELISA) and expression of AKT/AKT-P (CASE ELISA/western blot) in response to chromogranin A silencing, inhibition of prohormone convertase and mTOR inhibition (RAD001/AKT antisense) as well as different chromogranin A fragments were examined in 4 SI-NEN cell lines. RESULTS Chromogranin A mRNA and protein levels were increased (37-340 fold, p<0.0001) in small intestinal NENs compared to normal enterochromaffin cells. Western blot identified chromogranin A-associated processing bands including vasostatin in small intestinal NENs as well as up-regulated expression of prohormone convertase in metastases. Proliferation in small intestinal NEN cell lines was decreased by silencing chromogranin A as well as by inhibition of prohormone convertase (p<0.05). This inhibition also decreased secretion of chromogranin A (p<0.05) and 5-HT (p<0.05) as well as expression of vasostatin. Metastatic small intestinal NEN cell lines were stimulated (50-80%, p<0.05) and AKT phosphorylated (Ser473: p<0.05) by vasostatin I, which was completely reversed by RAD001 (p<0.01) and AKT antisense (p<0.05) while chromostatin inhibited proliferation (~50%, p<0.05). CONCLUSION Chromogranin A was differentially regulated in primary and metastatic small intestinal NENs and cell lines. Chromogranin A fragments regulated metastatic small intestinal NEN proliferation via the AKT pathway indicating that CgA plays a far more complex role in the biology of these tumors than previously considered.
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Affiliation(s)
- Francesco Giovinazzo
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut, United States of America
- Laboratory of Translational Surgery-LURM, University of Verona, Verona, Italy
| | - Simon Schimmack
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut, United States of America
- University Hospital of General, Visceral- and Transplantation-Surgery of Heidelberg, Heidelberg, Germany
| | - Bernhard Svejda
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut, United States of America
- Department of Pathophysiology and Immunology, University of Graz, Graz, Austria
| | - Daniele Alaimo
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Roswitha Pfragner
- Department of Pathophysiology and Immunology, University of Graz, Graz, Austria
| | - Irvin Modlin
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Mark Kidd
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut, United States of America
- * E-mail:
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Purinergic autocrine regulation of mechanosensitivity and serotonin release in a human EC model: ATP-gated P2X3 channels in EC are downregulated in ulcerative colitis. Inflamm Bowel Dis 2013; 19:2366-79. [PMID: 23917247 PMCID: PMC4037929 DOI: 10.1097/mib.0b013e31829ecf4d] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Alterations in 5-hydroxytryptamine (HT) signaling in inflamed gut may contribute to pathogenesis of inflammatory bowel diseases. Adenosine 5'-triphosphate (ATP) regulates mucosal-mechanosensory reflexes and ATP receptors are sensitive to mucosal inflammation. Yet, it remains unknown whether ATP can modulate 5-HT signaling in enterochromaffin cells (EC). We tested the novel purinergic hypothesis that ATP is a critical autocrine regulator of EC mechanosensitivity and whether EC expression of ATP-gated P2X3-ion channels is altered in inflammatory bowel diseases. METHODS Laser confocal (fluo-4) Ca imaging was performed in 1947 BON cells. Chemical stimulation or mechanical stimulation (MS) was used to study 5-HT or ATP release in human BON or surgical mucosal specimens, and purine receptors by reverse transcription-polymerase chain reaction, Western Blot, or P2X3-immunoreactivity in BON or 5-HT human EC (hEC) in 11 control and 10 severely inflamed ulcerative colitis (UC) cases. RESULTS ATP or MS triggered Ca-transients or 5-HT release in BON. ATP or adenosine diphosphate increased 5-HT release 5-fold. MS caused ATP release, detected after 5'ecto-ATPase inhibition by ARL67156. ARL67156 augmented and apyrase blocked Ca/5-HT mechanosensitive responses. 2-Methyl-thio-adenosine diphosphate 5'-monophosphate-evoked (P2Y1,12) or mechanically-evoked responses were blocked or augmented by a P2Y1,12 antagonist, MRS2179, in different cells or inhibited by U73122. A P2Y12 antagonist, 2MeSAMP, augmented responses. A P2X1,3 agonist, α,β-MeATP, triggered Ca responses, whereas a P2X1,2/3,3 antagonist, 2',3'-O-(2,4,6-trinitrophenyl)-ATP, blocked mechanical responses or cell-surface 5'ATP- labeling. In hEC, α,β-MeATP stimulated 5-HT release. In UC, P2X3-immunoreactivity decreased from 15% to 0.2% of 5-HThECs. Human mucosa and BON expressed P2X1, P2X3, P2X4, P2X5, P2Y1, P2Y2, P2Y4, P2Y6, P2Y11, and P2Y12R-messenger RNA transcripts. CONCLUSIONS ATP is a critical determinant of mechanosensation and 5-HT release via autocrine activation of slow P2Y1-phospholipase C/inositol-1,4,5-triphosphate-Ca or inhibitory P2Y12-purinergic pathways, and fast ATP-gated P2X3-channels. UC downregulation of P2X3-channels (or A2B) is postulated to mediate abnormal 5-HT signaling.
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Biological clocks in the duodenum and the diurnal regulation of duodenal and plasma serotonin. PLoS One 2013; 8:e58477. [PMID: 23737937 PMCID: PMC3667830 DOI: 10.1371/journal.pone.0058477] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Accepted: 02/05/2013] [Indexed: 11/19/2022] Open
Abstract
Serotonin in blood plasma is primarily synthesized in the duodenum, as brain derived serotonin does not cross the blood-brain barrier. Because serotonin in the brain and retina is synthesized under the control of a circadian clock, we sought to determine if a circadian clock in the duodenum regulates serotonin synthesis and release in blood. We examined gene expression in the duodenum of chickens at different times of the day and found that the duodenum rhythmically expresses molecular circadian clock genes and genes controlling serotonin biosynthesis, specifically tryptophan hydroxylase, in a light dark cycle (LD). Analysis of the duodenum and blood plasma showed that the amount of serotonin in the duodenum varies across the day and that serotonin profiles in blood plasma are also rhythmic in LD, but were not rhythmic in constant darkness. Because serotonin in the gut affects duodenal nutrient absorption and gut motility, the control of serotonin production in the duodenum by LD cycles could provide an additional mechanism by which the external environment controls nutrient uptake and digestive function. The diurnal regulation of plasma serotonin may also serve as an additional biochemical signal in the blood encoding time and could be used by target tissues to indicate the status of nutrient absorption.
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Damen R, Haugen M, Svejda B, Alaimo D, Brenna O, Pfragner R, Gustafsson BI, Kidd M. The stimulatory adenosine receptor ADORA2B regulates serotonin (5-HT) synthesis and release in oxygen-depleted EC cells in inflammatory bowel disease. PLoS One 2013; 8:e62607. [PMID: 23638125 PMCID: PMC3637445 DOI: 10.1371/journal.pone.0062607] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 03/27/2013] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVE We recently demonstrated that hypoxia, a key feature of IBD, increases enterochromaffin (EC) cell 5-HT secretion, which is also physiologically regulated by the ADORA2B mechanoreceptor. Since hypoxia is associated with increased extracellular adenosine, we wanted to examine whether this nucleotide amplifies HIF-1α-mediated 5-HT secretion. DESIGN The effects of hypoxia were studied on IBD mucosa, isolated IBD-EC cells, isolated normal EC cells and the EC cell tumor derived cell line KRJ-1. Hypoxia (0.5% O2) was compared to NECA (adenosine agonist), MRS1754 (ADORA2B receptor antagonist) and SCH442146 (ADORA2A antagonist) on HIF signaling and 5-HT secretion. Antisense approaches were used to mechanistically evaluate EC cells in vitro. PCR and western blot were used to analyze transcript and protein levels of HIF-1α signaling and neuroendocrine cell function. An animal model of colitis was evaluated to confirm hypoxia:adenosine signaling in vivo. RESULTS HIF-1α is upregulated in IBD mucosa and IBD-EC cells, the majority (~90%) of which express an activated phenotype in situ. Hypoxia stimulated 5-HT release maximally at 30 mins, an effect amplified by NECA and selectively inhibited by MRS1754, through phosphorylation of TPH-1 and activation of VMAT-1. Transient transfection with Renilla luciferase under hypoxia transcriptional response element (HRE) control identified that ADORA2B activated HIF-1α signaling under hypoxic conditions. Additional signaling pathways associated with hypoxia:adenosine included MAP kinase and CREB. Antisense approaches mechanistically confirmed that ADORA2B signaling was linked to these pathways and 5-HT release under hypoxic conditions. Hypoxia:adenosine activation which could be reversed by 5'-ASA treatment was confirmed in a TNBS-model. CONCLUSION Hypoxia induced 5-HT synthesis and secretion is amplified by ADORA2B signaling via MAPK/CREB and TPH-1 activation. Targeting ADORA2s may decrease EC cell 5-HT production and secretion in IBD.
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Affiliation(s)
- Rikard Damen
- Gastrointestinal Pathobiology Research Group, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Martin Haugen
- Gastrointestinal Pathobiology Research Group, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Bernhard Svejda
- Gastrointestinal Pathobiology Research Group, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Daniele Alaimo
- Gastrointestinal Pathobiology Research Group, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Oystein Brenna
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Roswitha Pfragner
- Institute of Pathophysiology and Immunology, Centre for Molecular Medicine, Graz, Austria
| | - Bjorn I. Gustafsson
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Mark Kidd
- Gastrointestinal Pathobiology Research Group, Yale University School of Medicine, New Haven, Connecticut, United States of America
- * E-mail:
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