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Damage-associated molecular pattern recognition is required for induction of retinal neuroprotective pathways in a sex-dependent manner. Sci Rep 2018; 8:9115. [PMID: 29904087 PMCID: PMC6002365 DOI: 10.1038/s41598-018-27479-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 06/04/2018] [Indexed: 12/29/2022] Open
Abstract
Retinal degeneration is a common cause of irreversible blindness and is caused by the death of retinal light-sensitive neurons called photoreceptors. At the onset of degeneration, stressed photoreceptors cause retinal glial cells to secrete neuroprotective factors that slow the pace of degeneration. Leukemia inhibitory factor (LIF) is one such factor that is required for endogenous neuroprotection. Photoreceptors are known to release signals of cellular stress, called damage-associated molecular patterns (DAMPs) early in degeneration, and we hypothesized that receptors for DAMPs or pattern recognition receptors (PRRs) play a key role in the induction of LIF and neuroprotective stress responses in retinal glial cells. Toll-like receptor 2 (TLR2) is a well-established DAMP receptor. In our experiments, activation of TLR2 protected both male and female mice from light damage, while the loss of TLR2 in female mice did not impact photoreceptor survival. In contrast, induction of protective stress responses, microglial phenotype and photoreceptor survival were strongly impacted in male TLR2−/− mice. Lastly, using publicly available gene expression data, we show that TLR2 is expressed highly in resting microglia prior to injury, but is also induced in Müller cells in inherited retinal degeneration.
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52
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Caputi V, Giron MC. Microbiome-Gut-Brain Axis and Toll-Like Receptors in Parkinson's Disease. Int J Mol Sci 2018; 19:ijms19061689. [PMID: 29882798 PMCID: PMC6032048 DOI: 10.3390/ijms19061689] [Citation(s) in RCA: 209] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 05/31/2018] [Accepted: 06/03/2018] [Indexed: 12/14/2022] Open
Abstract
Parkinson’s disease (PD) is a progressively debilitating neurodegenerative disease characterized by α-synucleinopathy, which involves all districts of the brain-gut axis, including the central, autonomic and enteric nervous systems. The highly bidirectional communication between the brain and the gut is markedly influenced by the microbiome through integrated immunological, neuroendocrine and neurological processes. The gut microbiota and its relevant metabolites interact with the host via a series of biochemical and functional inputs, thereby affecting host homeostasis and health. Indeed, a dysregulated microbiota-gut-brain axis in PD might lie at the basis of gastrointestinal dysfunctions which predominantly emerge many years prior to the diagnosis, corroborating the theory that the pathological process is spread from the gut to the brain. Toll-like receptors (TLRs) play a crucial role in innate immunity by recognizing conserved motifs primarily found in microorganisms and a dysregulation in their signaling may be implicated in α-synucleinopathy, such as PD. An overstimulation of the innate immune system due to gut dysbiosis and/or small intestinal bacterial overgrowth, together with higher intestinal barrier permeability, may provoke local and systemic inflammation as well as enteric neuroglial activation, ultimately triggering the development of alpha-synuclein pathology. In this review, we provide the current knowledge regarding the relationship between the microbiota-gut⁻brain axis and TLRs in PD. A better understanding of the dialogue sustained by the microbiota-gut-brain axis and innate immunity via TLR signaling should bring interesting insights in the pathophysiology of PD and provide novel dietary and/or therapeutic measures aimed at shaping the gut microbiota composition, improving the intestinal epithelial barrier function and balancing the innate immune response in PD patients, in order to influence the early phases of the following neurodegenerative cascade.
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Affiliation(s)
- Valentina Caputi
- Pharmacology Building, Department of Pharmaceutical and Pharmacological Sciences, University of Padova, 35131 Padova, Italy.
- APC Microbiome Ireland, University College Cork, T12YT20 Cork, Ireland.
| | - Maria Cecilia Giron
- Pharmacology Building, Department of Pharmaceutical and Pharmacological Sciences, University of Padova, 35131 Padova, Italy.
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Abstract
Microfluidic organ-on-a-chip models of human intestine have been developed and used to study intestinal physiology and pathophysiology. In this article, we review this field and describe how microfluidic Intestine Chips offer new capabilities not possible with conventional culture systems or organoid cultures, including the ability to analyze contributions of individual cellular, chemical, and physical control parameters one-at-a-time; to coculture human intestinal cells with commensal microbiome for extended times; and to create human-relevant disease models. We also discuss potential future applications of human Intestine Chips, including how they might be used for drug development and personalized medicine.
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54
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Mu Q, Tavella VJ, Luo XM. Role of Lactobacillus reuteri in Human Health and Diseases. Front Microbiol 2018; 9:757. [PMID: 29725324 PMCID: PMC5917019 DOI: 10.3389/fmicb.2018.00757] [Citation(s) in RCA: 385] [Impact Index Per Article: 64.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 04/04/2018] [Indexed: 12/13/2022] Open
Abstract
Lactobacillus reuteri (L. reuteri) is a well-studied probiotic bacterium that can colonize a large number of mammals. In humans, L. reuteri is found in different body sites, including the gastrointestinal tract, urinary tract, skin, and breast milk. The abundance of L. reuteri varies among different individuals. Several beneficial effects of L. reuteri have been noted. First, L. reuteri can produce antimicrobial molecules, such as organic acids, ethanol, and reuterin. Due to its antimicrobial activity, L. reuteri is able to inhibit the colonization of pathogenic microbes and remodel the commensal microbiota composition in the host. Second, L. reuteri can benefit the host immune system. For instance, some L. reuteri strains can reduce the production of pro-inflammatory cytokines while promoting regulatory T cell development and function. Third, bearing the ability to strengthen the intestinal barrier, the colonization of L. reuteri may decrease the microbial translocation from the gut lumen to the tissues. Microbial translocation across the intestinal epithelium has been hypothesized as an initiator of inflammation. Therefore, inflammatory diseases, including those located in the gut as well as in remote tissues, may be ameliorated by increasing the colonization of L. reuteri. Notably, the decrease in the abundance of L. reuteri in humans in the past decades is correlated with an increase in the incidences of inflammatory diseases over the same period of time. Direct supplementation or prebiotic modulation of L. reuteri may be an attractive preventive and/or therapeutic avenue against inflammatory diseases.
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Affiliation(s)
| | | | - Xin M. Luo
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, United States
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55
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Beckett EAH, Staikopoulos V, Hutchinson MR. Differential effect of morphine on gastrointestinal transit, colonic contractions and nerve-evoked relaxations in Toll-Like Receptor deficient mice. Sci Rep 2018; 8:5923. [PMID: 29651005 PMCID: PMC5897409 DOI: 10.1038/s41598-018-23717-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 03/20/2018] [Indexed: 12/13/2022] Open
Abstract
Toll-like receptors (TLRs) are expressed in enteric neurons, glia, gastrointestinal (GI) smooth muscle and mucosa, yet their functional roles in the GI tract are not fully understood. TLRs have been linked to many of the undesirable central effects of chronic opioid administration including hyperalgesia and dependence via activation of central microglia. Opioid-induced bowel dysfunction (OIBD) remains a primary reason for the reduction or withdrawal of opioid analgesics. Morphine-induced inhibition of colonic motility was assessed in vivo by GI transit studies and in vitro using isolated colons from wildtype (WT) and TLR deficient mice. Morphine slowed movement of ingested content in WT but this retardation effect was attenuated in TLR4−/− and TLR2/4−/−. In isolated colons, morphine reduced amplitude and frequency colonic migrating motor contractions in both WT and TLR2/4−/−. Electrical field stimulation elicited distal colon relaxation that was potentiated by morphine in WT but not in TLR2/4−/−. Inhibitory junction potentials were of similar amplitude and kinetics in WT and TLR2/4−/− distal colon and not altered by morphine. Enteric nerve density and proportion of nitrergic nerves were similar in WT and TLR2/4−/− distal colon. These data suggest an involvement of TLRs in opioid pharmacodynamics and thus a potential interventional target for OIBD.
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Affiliation(s)
- Elizabeth A H Beckett
- Discipline of Physiology, Adelaide Medical School, University of Adelaide, Adelaide, South Australia, 5005, Australia.
| | - Vasiliki Staikopoulos
- Discipline of Physiology, Adelaide Medical School, University of Adelaide, Adelaide, South Australia, 5005, Australia.,Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - Mark R Hutchinson
- Discipline of Physiology, Adelaide Medical School, University of Adelaide, Adelaide, South Australia, 5005, Australia.,Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, University of Adelaide, Adelaide, South Australia, 5005, Australia
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56
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Brun P, Qesari M, Marconi PC, Kotsafti A, Porzionato A, Macchi V, Schwendener RA, Scarpa M, Giron MC, Palù G, Calistri A, Castagliuolo I. Herpes Simplex Virus Type 1 Infects Enteric Neurons and Triggers Gut Dysfunction via Macrophage Recruitment. Front Cell Infect Microbiol 2018; 8:74. [PMID: 29600197 PMCID: PMC5862801 DOI: 10.3389/fcimb.2018.00074] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 02/27/2018] [Indexed: 12/27/2022] Open
Abstract
Herpes Simplex Virus type 1 (HSV-1), a neurotropic pathogen widespread in human population, infects the enteric nervous system (ENS) in humans and rodents and causes intestinal neuromuscular dysfunction in rats. Although infiltration of inflammatory cells in the myenteric plexus and neurodegeneration of enteric nerves are common features of patients suffering from functional intestinal disorders, the proof of a pathogenic link with HSV-1 is still unsettled mainly because the underlying mechanisms are largely unknown. In this study we demonstrated that following intragastrical administration HSV-1 infects neurons within the myenteric plexus resulting in functional and structural alterations of the ENS. By infecting mice with HSV-1 replication-defective strain we revealed that gastrointestinal neuromuscular anomalies were however independent of viral replication. Indeed, enteric neurons exposed to UV-inactivated HSV-1 produced monocyte chemoattractant protein-1 (MCP-1/CCL2) to recruit activated macrophages in the longitudinal muscle myenteric plexus. Infiltrating macrophages produced reactive oxygen and nitrogen species and directly harmed enteric neurons resulting in gastrointestinal dysmotility. In HSV-1 infected mice intestinal neuromuscular dysfunctions were ameliorated by in vivo administration of (i) liposomes containing dichloromethylene bisphosphonic acid (clodronate) to deplete tissue macrophages, (ii) CCR2 chemokine receptor antagonist RS504393 to block the CCL2/CCR2 pathway, (iii) Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME) and AR-C 102222 to quench production of nitrogen reactive species produced via iNOS. Overall these data demonstrate that HSV-1 infection makes enteric neurons recruit macrophages via production of a specific chemoattractant factor. The resulting inflammatory reaction is mandatory for intestinal dysmotility. These findings provide insights into the neuro-immune communication that occurs in the ENS following HSV-1 infection and allow recognition of an original pathophysiologic mechanism underlying gastrointestinal diseases as well as identification of novel therapeutic targets.
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Affiliation(s)
- Paola Brun
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Marsela Qesari
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy
| | - Peggy C Marconi
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Andromachi Kotsafti
- Esophageal and Digestive Tract Surgery Unit, Veneto Institute of Oncology IOV-IRCCS, Padova, Italy
| | | | - Veronica Macchi
- Department of Neurosciences, University of Padova, Padova, Italy
| | - Reto A Schwendener
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - Marco Scarpa
- Esophageal and Digestive Tract Surgery Unit, Veneto Institute of Oncology IOV-IRCCS, Padova, Italy
| | - Maria C Giron
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy
| | - Giorgio Palù
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Arianna Calistri
- Department of Molecular Medicine, University of Padova, Padova, Italy
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57
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Brun P, Akbarali HI. Culture of Neurons and Smooth Muscle Cells from the Myenteric Plexus of Adult Mice. Methods Mol Biol 2018; 1727:119-125. [PMID: 29222777 PMCID: PMC8841101 DOI: 10.1007/978-1-4939-7571-6_9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In the enteric nervous system, neurons make contact with smooth muscle cells to regulate gastrointestinal functions. Since neuronal cell alterations and intestinal motor dysfunctions are strictly linked, in vitro models based on the culture of neurons or smooth muscle cells are of great advantage to elucidate the functions of the enteric nervous system under physiological and pathological conditions. In this chapter, we provide the protocol for isolation of neurons and smooth muscle cells from the myenteric plexus of adult mice. The isolated cells are suitable for immunocytochemical applications or electrophysiological investigations and/or co-culturing experiments.
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Affiliation(s)
- Paola Brun
- Department of Molecular Medicine, University of Padua, Padua, Italy.
| | - Hamid I Akbarali
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
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58
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AL-QUDAH M, SHAMMALA DA, AL-DWAIRI A, AL-SHBOUL O, MUSTAFA AG. Dextran Sodium Sulphate (DSS)-Induced Colitis Alters the Expression of Neurotrophins in Smooth Muscle Cells of Rat Colon. Physiol Res 2017; 66:1009-1020. [DOI: 10.33549/physiolres.933465] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Neurotrophins are present in the gastrointestinal tract where they participate in the survival and growth of enteric neurons, augmentation of enteric circuits, elevation of colonic myoelectrical activity and also in different aspects of colitis. Previous studies largely focused on the role of neural and mucosal neurotrophins in gut inflammation. The expression of neurotrophins in colonic smooth muscle cells (SMCs) and the interactions of this potential source with colitis has not been studied in the gut. The expression of NGF, BDNF, NT-3 and NT-4 in SMCs from longitudinal and circular muscle layers of rat colon from normal and dextran sodium sulphate (DSS)-induced colitis rats was measured by ELISA. NGF, BDNF, NT-3 and NT-4 are differentially expressed in both longitudinal and circular SMCs, where the expressions of BDNF and NT-4 proteins were greater in SMCs from the longitudinal muscle layer than from the circular muscle layer, while NGF protein expression was greater in circular SMCs and NT-3 expression was equal in cells from both muscle layers. Induction of colitis with DSS significantly alters neurotrophins expression pattern in colonic SMCs. NGF levels upregulated in circular SMCs. BDNF level was increased in DSS-induced colitis in longitudinal SMCs. NGF, NT-3 and NT-4 levels were downregulated in longitudinal SMCs of DSS-induced colitis rats' colon. Disturbances of neurotrophins expression in SMCs resulted from colitis might account for the structural and functional changes in inflammatory bowel disease (IBD) such as loss of innervation and characteristic hypercontractility of longitudinal muscle in IBD.
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Affiliation(s)
- M. AL-QUDAH
- Department of Physiology, Jordan University of Science and Technology, Irbid, Jordan
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59
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Caputi V, Marsilio I, Filpa V, Cerantola S, Orso G, Bistoletti M, Paccagnella N, De Martin S, Montopoli M, Dall'Acqua S, Crema F, Di Gangi I, Galuppini F, Lante I, Bogialli S, Rugge M, Debetto P, Giaroni C, Giron MC. Antibiotic-induced dysbiosis of the microbiota impairs gut neuromuscular function in juvenile mice. Br J Pharmacol 2017; 174:3623-3639. [PMID: 28755521 PMCID: PMC5610159 DOI: 10.1111/bph.13965] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 07/18/2017] [Accepted: 07/19/2017] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND AND PURPOSE Gut microbiota is essential for the development of the gastrointestinal system, including the enteric nervous system (ENS). Perturbations of gut microbiota in early life have the potential to alter neurodevelopment leading to functional bowel disorders later in life. We examined the hypothesis that gut dysbiosis impairs the structural and functional integrity of the ENS, leading to gut dysmotility in juvenile mice. EXPERIMENTAL APPROACH To induce gut dysbiosis, broad-spectrum antibiotics were administered by gavage to juvenile (3weeks old) male C57Bl/6 mice for 14 days. Bile acid composition in the intestinal lumen was analysed by liquid chromatography-mass spectrometry. Changes in intestinal motility were evaluated by stool frequency, transit of a fluorescent-labelled marker and isometric muscle responses of ileal full-thickness preparations to receptor and non-receptor-mediated stimuli. Alterations in ENS integrity were assessed by immunohistochemistry and Western blot analysis. KEY RESULTS Antibiotic treatment altered gastrointestinal transit, luminal bile acid metabolism and bowel architecture. Gut dysbiosis resulted in distorted glial network, loss of myenteric plexus neurons, altered cholinergic, tachykininergic and nitrergic neurotransmission associated with reduced number of nNOS neurons and different ileal distribution of the toll-like receptor TLR2. Functional defects were partly reversed by activation of TLR2 signalling. CONCLUSIONS AND IMPLICATIONS Gut dysbiosis caused complex morpho-functional neuromuscular rearrangements, characterized by structural defects of the ENS and increased tachykininergic neurotransmission. Altogether, our findings support the beneficial role of enteric microbiota for ENS homeostasis instrumental in ensuring proper gut neuromuscular function during critical stages of development.
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Affiliation(s)
- Valentina Caputi
- Department of Pharmaceutical and Pharmacological SciencesUniversity of PadovaPadovaItaly
| | - Ilaria Marsilio
- Department of Pharmaceutical and Pharmacological SciencesUniversity of PadovaPadovaItaly
| | - Viviana Filpa
- Department of Medicine and SurgeryUniversity of InsubriaVareseItaly
| | - Silvia Cerantola
- Department of Pharmaceutical and Pharmacological SciencesUniversity of PadovaPadovaItaly
- San Camillo HospitalTrevisoItaly
| | - Genny Orso
- IRCCS ‘E. Medea’ Bosisio PariniLeccoItaly
| | | | - Nicola Paccagnella
- Department of Pharmaceutical and Pharmacological SciencesUniversity of PadovaPadovaItaly
| | - Sara De Martin
- Department of Pharmaceutical and Pharmacological SciencesUniversity of PadovaPadovaItaly
| | - Monica Montopoli
- Department of Pharmaceutical and Pharmacological SciencesUniversity of PadovaPadovaItaly
| | - Stefano Dall'Acqua
- Department of Pharmaceutical and Pharmacological SciencesUniversity of PadovaPadovaItaly
| | - Francesca Crema
- Department of Internal Medicine and Therapeutics, Section of PharmacologyUniversity of PaviaPaviaItaly
| | | | | | | | - Sara Bogialli
- Department of Chemical SciencesUniversity of PadovaPadovaItaly
| | - Massimo Rugge
- Department of MedicineUniversity of PadovaPadovaItaly
| | - Patrizia Debetto
- Department of Pharmaceutical and Pharmacological SciencesUniversity of PadovaPadovaItaly
| | - Cristina Giaroni
- Department of Medicine and SurgeryUniversity of InsubriaVareseItaly
| | - Maria Cecilia Giron
- Department of Pharmaceutical and Pharmacological SciencesUniversity of PadovaPadovaItaly
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60
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Yoo BB, Mazmanian SK. The Enteric Network: Interactions between the Immune and Nervous Systems of the Gut. Immunity 2017; 46:910-926. [PMID: 28636959 PMCID: PMC5551410 DOI: 10.1016/j.immuni.2017.05.011] [Citation(s) in RCA: 289] [Impact Index Per Article: 41.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Revised: 05/25/2017] [Accepted: 05/31/2017] [Indexed: 12/16/2022]
Abstract
Interactions between the nervous and immune systems enable the gut to respond to the variety of dietary products that it absorbs, the broad spectrum of pathogens that it encounters, and the diverse microbiome that it harbors. The enteric nervous system (ENS) senses and reacts to the dynamic ecosystem of the gastrointestinal (GI) tract by translating chemical cues from the environment into neuronal impulses that propagate throughout the gut and into other organs in the body, including the central nervous system (CNS). This review will describe the current understanding of the anatomy and physiology of the GI tract by focusing on the ENS and the mucosal immune system. We highlight emerging literature that the ENS is essential for important aspects of microbe-induced immune responses in the gut. Although most basic and applied research in neuroscience has focused on the brain, the proximity of the ENS to the immune system and its interface with the external environment suggest that novel paradigms for nervous system function await discovery.
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Affiliation(s)
- Bryan B Yoo
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
| | - Sarkis K Mazmanian
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
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61
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Caputi V, Marsilio I, Cerantola S, Roozfarakh M, Lante I, Galuppini F, Rugge M, Napoli E, Giulivi C, Orso G, Giron MC. Toll-Like Receptor 4 Modulates Small Intestine Neuromuscular Function through Nitrergic and Purinergic Pathways. Front Pharmacol 2017. [PMID: 28642706 PMCID: PMC5463746 DOI: 10.3389/fphar.2017.00350] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Objective: Toll-like receptors (TLRs) play a pivotal role in the homeostatic microflora-host crosstalk. TLR4-mediated modulation of both motility and enteric neuronal survival has been reported mainly for colon with limited information on the role of TLR4 in tuning structural and functional integrity of enteric nervous system (ENS) and in controlling small bowel motility. Methods: Male TLR4 knockout (TLR4-/-, 9 ± 1 weeks old) and sex- and age-matched wild-type (WT) C57BL/6J mice were used for the experiments. Alterations in ENS morphology and neurochemical code were assessed by immunohistochemistry whereas neuromuscular function was evaluated by isometric mechanical activity of ileal preparations following receptor and non-receptor-mediated stimuli and by gastrointestinal transit. Results: The absence of TLR4 induced gliosis and reduced the total number of neurons, mainly nNOS+ neurons, in ileal myenteric plexus. Furthermore, a lower cholinergic excitatory response with an increased inhibitory neurotransmission was found together with a delayed gastrointestinal transit. These changes were dependent on increased ileal non-adrenergic non-cholinergic (NANC) relaxations mediated by a complex neuronal-glia signaling constituted by P2X7 and P2Y1 receptors, and NO produced by nNOS and iNOS. Conclusion: We provide novel evidence that TLR4 signaling is involved in the fine-tuning of P2 receptors controlling ileal contractility, ENS cell distribution, and inhibitory NANC neurotransmission via the combined action of NO and adenosine-5'-triphosphate (ATP). For the first time, this study implicates TLR4 at regulating the crosstalk between glia and neurons in small intestine and helps to define its role in gastrointestinal motor abnormalities during dysbiosis.
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Affiliation(s)
- Valentina Caputi
- Department of Pharmaceutical and Pharmacological Sciences, School of Medicine, University of PadovaPadova, Italy
| | - Ilaria Marsilio
- Department of Pharmaceutical and Pharmacological Sciences, School of Medicine, University of PadovaPadova, Italy
| | - Silvia Cerantola
- Department of Pharmaceutical and Pharmacological Sciences, School of Medicine, University of PadovaPadova, Italy.,San Camillo HospitalTreviso, Italy
| | - Mona Roozfarakh
- Medway School of Pharmacy, Universities of Kent and Greenwich at MedwayKent, United Kingdom
| | | | | | - Massimo Rugge
- Department of Medicine, University of PadovaPadova, Italy
| | - Eleonora Napoli
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, DavisCA, United States
| | - Cecilia Giulivi
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, DavisCA, United States.,Medical Investigation of Neurodevelopmental Disorders Institute (M.I.N.D.), University of California, Davis, SacramentoCA, United States
| | - Genny Orso
- IRCCS "E. Medea" Bosisio PariniLecco, Italy
| | - Maria Cecilia Giron
- Department of Pharmaceutical and Pharmacological Sciences, School of Medicine, University of PadovaPadova, Italy
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62
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Veiga-Fernandes H, Pachnis V. Neuroimmune regulation during intestinal development and homeostasis. Nat Immunol 2017; 18:116-122. [DOI: 10.1038/ni.3634] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 11/07/2016] [Indexed: 12/22/2022]
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63
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Veiga-Fernandes H, Mucida D. Neuro-Immune Interactions at Barrier Surfaces. Cell 2017; 165:801-11. [PMID: 27153494 DOI: 10.1016/j.cell.2016.04.041] [Citation(s) in RCA: 173] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Indexed: 12/23/2022]
Abstract
Multidirectional interactions between the nervous and immune systems have been documented in homeostasis and pathologies ranging from multiple sclerosis to autism, and from leukemia to acute and chronic inflammation. Recent studies have addressed this crosstalk using cell-specific targeting, novel sequencing, imaging, and analytical tools, shedding light on unappreciated mechanisms of neuro-immune regulation. This Review focuses on neuro-immune interactions at barrier surfaces-mostly the gut, but also including the skin and the airways, areas densely populated by neurons and immune cells that constantly sense and adapt to tissue-specific environmental challenges.
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Affiliation(s)
- Henrique Veiga-Fernandes
- Instituto de Medicina Molecular, Faculdade de Medicina de Lisboa, Av. Prof. Egas Moniz, Edifício Egas Moniz, 1649-028 Lisboa, Portugal.
| | - Daniel Mucida
- Laboratory of Mucosal Immunology, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
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64
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Guarino MPL, Cicala M, Putignani L, Severi C. Gastrointestinal neuromuscular apparatus: An underestimated target of gut microbiota. World J Gastroenterol 2016; 22:9871-9879. [PMID: 28018095 PMCID: PMC5143755 DOI: 10.3748/wjg.v22.i45.9871] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 10/13/2016] [Accepted: 11/16/2016] [Indexed: 02/06/2023] Open
Abstract
Over the last few years, the importance of the resident intestinal microbiota in the pathogenesis of several gastro-intestinal diseases has been largely investigated. Growing evidence suggest that microbiota can influence gastro-intestinal motility. The current working hypothesis is that dysbiosis-driven mucosal alterations induce the production of several inflammatory/immune mediators which affect gut neuro-muscular functions. Besides these indirect mucosal-mediated effects, the present review highlights that recent evidence suggests that microbiota can directly affect enteric nerves and smooth muscle cells functions through its metabolic products or bacterial molecular components translocated from the intestinal lumen. Toll-like receptors, the bacterial recognition receptors, are expressed both on enteric nerves and smooth muscle and are emerging as potential mediators between microbiota and the enteric neuromuscular apparatus. Furthermore, the ongoing studies on probiotics support the hypothesis that the neuromuscular apparatus may represent a target of intervention, thus opening new physiopathological and therapeutic scenarios.
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65
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Sherwin E, Sandhu KV, Dinan TG, Cryan JF. May the Force Be With You: The Light and Dark Sides of the Microbiota-Gut-Brain Axis in Neuropsychiatry. CNS Drugs 2016; 30:1019-1041. [PMID: 27417321 PMCID: PMC5078156 DOI: 10.1007/s40263-016-0370-3] [Citation(s) in RCA: 178] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The role of the gut microbiota in health and disease is becoming increasingly recognized. The microbiota-gut-brain axis is a bi-directional pathway between the brain and the gastrointestinal system. The bacterial commensals in our gut can signal to the brain through a variety of mechanisms, which are slowly being resolved. These include the vagus nerve, immune mediators and microbial metabolites, which influence central processes such as neurotransmission and behaviour. Dysregulation in the composition of the gut microbiota has been identified in several neuropsychiatric disorders, such as autism, schizophrenia and depression. Moreover, preclinical studies suggest that they may be the driving force behind the behavioural abnormalities observed in these conditions. Understanding how bacterial commensals are involved in regulating brain function may lead to novel strategies for development of microbiota-based therapies for these neuropsychiatric disorders.
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Affiliation(s)
- Eoin Sherwin
- APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Kiran V Sandhu
- APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Timothy G Dinan
- APC Microbiome Institute, University College Cork, Cork, Ireland
- Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland
| | - John F Cryan
- APC Microbiome Institute, University College Cork, Cork, Ireland.
- Department of Anatomy and Neuroscience, University College Cork, Western Gateway Building, Cork, Ireland.
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66
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Heuckeroth RO, Schäfer KH. Gene-environment interactions and the enteric nervous system: Neural plasticity and Hirschsprung disease prevention. Dev Biol 2016; 417:188-97. [PMID: 26997034 PMCID: PMC5026873 DOI: 10.1016/j.ydbio.2016.03.017] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 03/04/2016] [Accepted: 03/14/2016] [Indexed: 12/12/2022]
Abstract
Intestinal function is primarily controlled by an intrinsic nervous system of the bowel called the enteric nervous system (ENS). The cells of the ENS are neural crest derivatives that migrate into and through the bowel during early stages of organogenesis before differentiating into a wide variety of neurons and glia. Although genetic factors critically underlie ENS development, it is now clear that many non-genetic factors may influence the number of enteric neurons, types of enteric neurons, and ratio of neurons to glia. These non-genetic influences include dietary nutrients and medicines that may impact ENS structure and function before or after birth. This review summarizes current data about gene-environment interactions that affect ENS development and suggests that these factors may contribute to human intestinal motility disorders like Hirschsprung disease or irritable bowel syndrome.
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Affiliation(s)
- Robert O Heuckeroth
- Department of Pediatrics, The Children's Hospital of Philadelphia Research Institute, USA; The Perelman School of Medicine at the University of Pennsylvania, Abramson Research Center, 3615 Civic Center Boulevard, Philadelphia, PA 19104, USA.
| | - Karl-Herbert Schäfer
- ENS Group, University of Applied Sciences Kaiserslautern/Zweibrücken, Germany; University of Heidelberg, Paediatric Surgery Mannheim, Germany
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67
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Margolis KG, Gershon MD, Bogunovic M. Cellular Organization of Neuroimmune Interactions in the Gastrointestinal Tract. Trends Immunol 2016; 37:487-501. [PMID: 27289177 PMCID: PMC5003109 DOI: 10.1016/j.it.2016.05.003] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 04/19/2016] [Accepted: 05/09/2016] [Indexed: 02/06/2023]
Abstract
The gastrointestinal (GI) tract is the largest immune organ; in vertebrates, it is the only organ whose function is controlled by its own intrinsic enteric nervous system (ENS), but it is additionally regulated by extrinsic (sympathetic and parasympathetic) innervation. The GI nervous and immune systems are highly integrated in their common goal, which is to unite digestive functions with protection from ingested environmental threats. This review discusses the physiological relevance of enteric neuroimmune integration by summarizing the current knowledge of evolutionary and developmental pathways, cellular organization, and molecular mechanisms of neuroimmune interactions in health and disease.
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Affiliation(s)
- Kara Gross Margolis
- Department of Pediatrics, Morgan Stanley Children's Hospital, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - Michael David Gershon
- Department of Pathology and Cell Biology, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - Milena Bogunovic
- Department of Microbiology and Immunology, Penn State University College of Medicine, Hershey, PA, USA.
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68
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Marques C, Meireles M, Faria A, Calhau C. High-Fat Diet-Induced Dysbiosis as a Cause of Neuroinflammation. Biol Psychiatry 2016; 80:e3-4. [PMID: 26774967 DOI: 10.1016/j.biopsych.2015.10.027] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 10/01/2015] [Indexed: 12/26/2022]
Affiliation(s)
- Cláudia Marques
- Departamento de Bioquímica, Universidade do Porto, Porto, Portugal; Centro de Investigação em Tecnologias e Sistemas de Informação em Saúde, Porto, Portugal
| | - Manuela Meireles
- Departamento de Bioquímica, Universidade do Porto, Porto, Portugal
| | - Ana Faria
- Departamento de Bioquímica, Universidade do Porto, Porto, Portugal; Faculdade de Medicina, Faculdade de Ciências da Nutrição e da Alimentação, Universidade do Porto, Porto, Portugal; Faculdade de Ciências, Universidade do Porto, Porto, Portugal
| | - Conceição Calhau
- Departamento de Bioquímica, Universidade do Porto, Porto, Portugal.
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69
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Ratanasirintrawoot S, Israsena N. Stem Cells in the Intestine: Possible Roles in Pathogenesis of Irritable Bowel Syndrome. J Neurogastroenterol Motil 2016; 22:367-82. [PMID: 27184041 PMCID: PMC4930294 DOI: 10.5056/jnm16023] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 03/08/2016] [Indexed: 12/13/2022] Open
Abstract
Irritable bowel syndrome is one of the most common functional gastrointestinal (GI) disorders that significantly impair quality of life in patients. Current available treatments are still not effective and the pathophysiology of this condition remains unclearly defined. Recently, research on intestinal stem cells has greatly advanced our understanding of various GI disorders. Alterations in conserved stem cell regulatory pathways such as Notch, Wnt, and bone morphogenic protein/TGF-β have been well documented in diseases such as inflammatory bowel diseases and cancer. Interaction between intestinal stem cells and various signals from their environment is important for the control of stem cell self-renewal, regulation of number and function of specific intestinal cell types, and maintenance of the mucosal barrier. Besides their roles in stem cell regulation, these signals are also known to have potent effects on immune cells, enteric nervous system and secretory cells in the gut, and may be responsible for various aspects of pathogenesis of functional GI disorders, including visceral hypersensitivity, altered gut motility and low grade gut inflammation. In this article, we briefly summarize the components of these signaling pathways, how they can be modified by extrinsic factors and novel treatments, and provide evidenced support of their roles in the inflammation processes. Furthermore, we propose how changes in these signals may contribute to the symptom development and pathogenesis of irritable bowel syndrome.
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Affiliation(s)
- Sutheera Ratanasirintrawoot
- Stem Cell and Cell Therapy Research Unit, Chulalongkorn University, Bangkok, Thailand.,Department of Research Affairs, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Nipan Israsena
- Stem Cell and Cell Therapy Research Unit, Chulalongkorn University, Bangkok, Thailand.,Department of Pharmacology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
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