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Thomasi B, Valdetaro L, Ricciardi MC, Gonçalves de Carvalho M, Fialho Tavares I, Tavares-Gomes AL. Enteric glia as a player of gut-brain interactions during Parkinson's disease. Front Neurosci 2023; 17:1281710. [PMID: 38027511 PMCID: PMC10644407 DOI: 10.3389/fnins.2023.1281710] [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: 08/22/2023] [Accepted: 10/10/2023] [Indexed: 12/01/2023] Open
Abstract
The enteric glia has been shown as a potential component of neuroimmune interactions that signal in the gut-brain axis during Parkinson's disease (PD). Enteric glia are a peripheral glial type found in the enteric nervous system (ENS) that, associated with enteric neurons, command various gastrointestinal (GI) functions. They are a unique cell type, with distinct phenotypes and distribution in the gut layers, which establish relevant neuroimmune modulation and regulate neuronal function. Comprehension of enteric glial roles during prodromal and symptomatic phases of PD should be a priority in neurogastroenterology research, as the reactive enteric glial profile, gastrointestinal dysfunction, and colonic inflammation have been verified during the prodromal phase of PD-a moment that may be interesting for interventions. In this review, we explore the mechanisms that should govern enteric glial signaling through the gut-brain axis to understand pathological events and verify the possible windows and pathways for therapeutic intervention. Enteric glia directly modulate several functional aspects of the intestine, such as motility, visceral sensory signaling, and immune polarization, key GI processes found deregulated in patients with PD. The search for glial biomarkers, the investigation of temporal-spatial events involving glial reactivity/signaling, and the proposal of enteric glia-based therapies are clearly demanded for innovative and intestine-related management of PD.
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Affiliation(s)
- Beatriz Thomasi
- Department of Physiology, Michigan State University, East Lansing, MI, United States
| | - Luisa Valdetaro
- Department of Molecular Pathobiology, NYU College of Dentistry, New York, NY, United States
| | - Maria Carolina Ricciardi
- Neuroglial Interaction Lab, Neuroscience Program, Universidade Federal Fluminense, Niterói, Brazil
| | | | - Isabela Fialho Tavares
- Neuroglial Interaction Lab, Neurobiology Department, Universidade Federal Fluminense, Niterói, Brazil
| | - Ana Lucia Tavares-Gomes
- Neuroglial Interaction Lab, Neuroscience Program, Universidade Federal Fluminense, Niterói, Brazil
- Neuroglial Interaction Lab, Neurobiology Department, Universidade Federal Fluminense, Niterói, Brazil
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2
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Thomasi B, Gulbransen B. Mini-review: Intercellular communication between enteric glia and neurons. Neurosci Lett 2023; 806:137263. [PMID: 37085112 PMCID: PMC10150911 DOI: 10.1016/j.neulet.2023.137263] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 04/13/2023] [Accepted: 04/17/2023] [Indexed: 04/23/2023]
Abstract
The enteric nervous system is a dense network of enteric neurons and glia housed in the gastrointestinal tract. This system is responsible for performing several functions that enable digestion as well as maintaining gut homeostasis through diverse signaling processes including those that arise from interactions with the immune system. Bidirectional communication between enteric neurons and enteric glia has gained increased attention for playing essential roles in enteric nervous system function. Neuronal mediators such as neurotransmitters stimulate enteric glia and subsequent gliotransmission processes refine neuronal signaling during intestinal motor control. In this mini-review, we present and discuss the basis of intercellular signaling between neurons and glia in the enteric nervous system and the relevance of these interactions to gut function.
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3
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The Enteric Glia and Its Modulation by the Endocannabinoid System, a New Target for Cannabinoid-Based Nutraceuticals? MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27196773. [PMID: 36235308 PMCID: PMC9570628 DOI: 10.3390/molecules27196773] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 09/21/2022] [Accepted: 09/26/2022] [Indexed: 11/29/2022]
Abstract
The enteric nervous system (ENS) is a part of the autonomic nervous system that intrinsically innervates the gastrointestinal (GI) tract. Whereas enteric neurons have been deeply studied, the enteric glial cells (EGCs) have received less attention. However, these are immune-competent cells that contribute to the maintenance of the GI tract homeostasis through supporting epithelial integrity, providing neuroprotection, and influencing the GI motor function and sensation. The endogenous cannabinoid system (ECS) includes endogenous classical cannabinoids (anandamide, 2-arachidonoylglycerol), cannabinoid-like ligands (oleoylethanolamide (OEA) and palmitoylethanolamide (PEA)), enzymes involved in their metabolism (FAAH, MAGL, COX-2) and classical (CB1 and CB2) and non-classical (TRPV1, GPR55, PPAR) receptors. The ECS participates in many processes crucial for the proper functioning of the GI tract, in which the EGCs are involved. Thus, the modulation of the EGCs through the ECS might be beneficial to treat some dysfunctions of the GI tract. This review explores the role of EGCs and ECS on the GI tract functions and dysfunctions, and the current knowledge about how EGCs may be modulated by the ECS components, as possible new targets for cannabinoids and cannabinoid-like molecules, particularly those with potential nutraceutical use.
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4
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Bhave S, Ho WLN, Cheng K, Omer M, Bousquet N, Guyer RA, Hotta R, Goldstein AM. Tamoxifen administration alters gastrointestinal motility in mice. Neurogastroenterol Motil 2022; 34:e14357. [PMID: 35279902 DOI: 10.1111/nmo.14357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 12/13/2021] [Accepted: 01/28/2022] [Indexed: 02/08/2023]
Abstract
BACKGROUND Tamoxifen is widely used for Cre-estrogen receptor-mediated genomic recombination in transgenic mouse models to mark cells for lineage tracing and to study gene function. However, recent studies have highlighted off-target effects of tamoxifen in various tissues and cell types when used for induction of Cre recombination. Despite the widespread use of these transgenic Cre models to assess gastrointestinal (GI) function, the effect of tamoxifen exposure on GI motility has not been described. METHODS We examined the effects of tamoxifen on GI motility by measuring total GI transit, gastric emptying, small intestinal transit, and colonic contractility in wild-type adult mice. KEY RESULTS We observed a significant delay in total GI transit in tamoxifen-treated mice, with unaltered gastric emptying, accelerated small intestinal transit, and abnormal colonic motility. CONCLUSION Our findings highlight the importance of considering GI motility alterations induced by tamoxifen when designing protocols that utilize tamoxifen as a Cre-driver for studying GI function.
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Affiliation(s)
- Sukhada Bhave
- Department of Pediatric Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Wing Lam N Ho
- Department of Pediatric Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Katarina Cheng
- Department of Pediatric Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Meredith Omer
- Department of Pediatric Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Nicole Bousquet
- Department of Pediatric Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Richard A Guyer
- Department of Pediatric Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Ryo Hotta
- Department of Pediatric Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Allan M Goldstein
- Department of Pediatric Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
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5
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Kirichenko EY, Skatchkov SN, Ermakov AM. Structure and Functions of Gap Junctions and Their Constituent Connexins in the Mammalian CNS. BIOCHEMISTRY MOSCOW SUPPLEMENT SERIES A-MEMBRANE AND CELL BIOLOGY 2021; 15:107-119. [PMID: 34512926 PMCID: PMC8432592 DOI: 10.1134/s1990747821020069] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Numerous data obtained in the last 20 years indicate that all parts of the mature central nervous system, from the retina and olfactory bulb to the spinal cord and brain, contain cells connected by gap junctions (GJs). The morphological basis of the GJs is a group of joined membrane hemichannels called connexons, the subunit of each connexon is the protein connexin. In the central nervous system, connexins show specificity and certain types of them are expressed either in neurons or in glial cells. Connexins and GJs of neurons, combining certain types of inhibitory hippocampal and neocortical neuronal ensembles, provide synchronization of local impulse and rhythmic activity, thalamocortical conduction, control of excitatory connections, which reflects their important role in the processes of perception, concentration of attention and consolidation of memory, both on the cellular and at the system level. Connexins of glial cells are ubiquitously expressed in the brain, and the GJs formed by them provide molecular signaling and metabolic cooperation and play a certain role in the processes of neuronal migration during brain development, myelination, tissue homeostasis, and apoptosis. At the same time, mutations in the genes of glial connexins, as well as a deficiency of these proteins, are associated with such diseases as congenital neuropathies, hearing loss, skin diseases, and brain tumors. This review summarizes the existing data of numerous molecular, electrophysiological, pharmacological, and morphological studies aimed at progress in the study of the physiological and pathophysiological significance of glial and neuronal connexins and GJs for the central nervous system.
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Affiliation(s)
- E Yu Kirichenko
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-on-Don, 344090 Russia
| | - S N Skatchkov
- Department of Biochemistry, School of Medicine, P.O. Box 60327, Universidad Central del Caribe, Bayamón, PR, 00960-6032 USA.,Department of Physiology, School of Medicine, P.O. Box 60327, Universidad Central del Caribe, Bayamón, PR, 00960-6032 USA
| | - A M Ermakov
- Faculty of Bioengineering and Veterinary Medicine, Don State Technical University, Rostov-on-Don, 344003 Russia
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6
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Seguella L, Gulbransen BD. Enteric glial biology, intercellular signalling and roles in gastrointestinal disease. Nat Rev Gastroenterol Hepatol 2021; 18:571-587. [PMID: 33731961 PMCID: PMC8324524 DOI: 10.1038/s41575-021-00423-7] [Citation(s) in RCA: 130] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/28/2021] [Indexed: 02/07/2023]
Abstract
One of the most transformative developments in neurogastroenterology is the realization that many functions normally attributed to enteric neurons involve interactions with enteric glial cells: a large population of peripheral neuroglia associated with enteric neurons throughout the gastrointestinal tract. The notion that glial cells function solely as passive support cells has been refuted by compelling evidence that demonstrates that enteric glia are important homeostatic cells of the intestine. Active signalling mechanisms between enteric glia and neurons modulate gastrointestinal reflexes and, in certain circumstances, function to drive neuroinflammatory processes that lead to long-term dysfunction. Bidirectional communication between enteric glia and immune cells contributes to gastrointestinal immune homeostasis, and crosstalk between enteric glia and cancer stem cells regulates tumorigenesis. These neuromodulatory and immunomodulatory roles place enteric glia in a unique position to regulate diverse gastrointestinal disease processes. In this Review, we discuss current concepts regarding enteric glial development, heterogeneity and functional roles in gastrointestinal pathophysiology and pathophysiology, with a focus on interactions with neurons and immune cells. We also present a working model to differentiate glial states based on normal function and disease-induced dysfunctions.
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Affiliation(s)
- Luisa Seguella
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, Rome, Italy
- Department of Physiology, Neuroscience Program, Michigan State University, East Lansing, MI, USA
| | - Brian D Gulbransen
- Department of Physiology, Neuroscience Program, Michigan State University, East Lansing, MI, USA.
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7
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Li Y, Wang Y, Chang H, Cheng B, Miao J, Li S, Hu H, Huang L, Wang Q. Inhibitory Effects of Dexmedetomidine and Propofol on Gastrointestinal Tract Motility Involving Impaired Enteric Glia Ca 2+ Response in Mice. Neurochem Res 2021; 46:1410-1422. [PMID: 33656693 DOI: 10.1007/s11064-021-03280-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 02/20/2021] [Accepted: 02/20/2021] [Indexed: 12/31/2022]
Abstract
Propofol and dexmedetomidine are popular used for sedation in ICU, however, inadequate attention has been paid to their effect on gastrointestinal tract (GIT) motility. Present study aimed to compare the effect of propofol and dexmedetomidine on GIT motility at parallel level of sedation and explore the possible mechanism. Male C57BL/6 mice (8-10 weeks) were randomly divided into control, propofol and dexmedetomidine group. After intraperitoneal injection of propofol or dexmedetomidine, comparable sedative level was confirmed by sedative score, physiological parameters and electroencephalogram (EEG). Different segments of GIT motility in vivo (gastric emptying, small intestine transit, distal colon bead expulsion, stool weight and number of fecal pellets, gastrointestinal transit and whole gut transit time) and colonic migrating motor complexes (CMMCs) pattern in vitro were evaluated. The Ca2+ response of primary enteric glia was examined under the treatment of propofol or dexmedetomidine. There is little difference in physiological parameters and composite permutation entropy index (CPEI) between administration of 50 mg/kg propofol and 40 μg/kg dexmedetomidine, indicated that parallel level of sedation was reached. Data showed that propofol and dexmedetomidine had significantly inhibitory effect on GIT motility while dexmedetomidine was stronger. Also, the amplitude (ΔF/F0) of Ca2+ response in primary enteric glia was attenuated after treated with the sedatives while the effect of dexmedetomidine was greater than propofol. These findings demonstrated that dexmedetomidine caused stronger inhibitory effects on GIT motility in sedative mice, which may involve impaired Ca2+ response in enteric glia. Hence, dexmedetomidine should be carefully applied especially for potential GIT dysmotility patient.
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Affiliation(s)
- Yansong Li
- Department of Anesthesiology & Center for Brain Science, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, Shaanxi, China
| | - Yubo Wang
- School of Life Science and Technology, Xidian University, Xi'an, 710061, Shaanxi, China
| | - Haiqing Chang
- Department of Anesthesiology & Center for Brain Science, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, Shaanxi, China
| | - Bo Cheng
- Department of Anesthesiology & Center for Brain Science, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, Shaanxi, China
| | - Jiwen Miao
- Department of Anesthesiology & Center for Brain Science, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, Shaanxi, China
| | - Shuang Li
- Department of Anesthesiology & Center for Brain Science, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, Shaanxi, China
| | - Hao Hu
- Department of Pharmacology, School of Basic Medical Sciences, Health Science Center, Xi'an Jiaotong University, Xi'an, 710061, Shaanxi, China
| | - Liyu Huang
- School of Life Science and Technology, Xidian University, Xi'an, 710061, Shaanxi, China
| | - Qiang Wang
- Department of Anesthesiology & Center for Brain Science, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, Shaanxi, China.
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8
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Broadhead MJ, Miles GB. A common role for astrocytes in rhythmic behaviours? Prog Neurobiol 2021; 202:102052. [PMID: 33894330 DOI: 10.1016/j.pneurobio.2021.102052] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 03/03/2021] [Accepted: 04/13/2021] [Indexed: 01/16/2023]
Abstract
Astrocytes are a functionally diverse form of glial cell involved in various aspects of nervous system infrastructure, from the metabolic and structural support of neurons to direct neuromodulation of synaptic activity. Investigating how astrocytes behave in functionally related circuits may help us understand whether there is any conserved logic to the role of astrocytes within neuronal networks. Astrocytes are implicated as key neuromodulatory cells within neural circuits that control a number of rhythmic behaviours such as breathing, locomotion and circadian sleep-wake cycles. In this review, we examine the evidence that astrocytes are directly involved in the regulation of the neural circuits underlying six different rhythmic behaviours: locomotion, breathing, chewing, gastrointestinal motility, circadian sleep-wake cycles and oscillatory feeding behaviour. We discuss how astrocytes are integrated into the neuronal networks that regulate these behaviours, and identify the potential gliotransmission signalling mechanisms involved. From reviewing the evidence of astrocytic involvement in a range of rhythmic behaviours, we reveal a heterogenous array of gliotransmission mechanisms, which help to regulate neuronal networks. However, we also observe an intriguing thread of commonality, in the form of purinergic gliotransmission, which is frequently utilised to facilitate feedback inhibition within rhythmic networks to constrain a given behaviour within its operational range.
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Affiliation(s)
- Matthew J Broadhead
- School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK.
| | - Gareth B Miles
- School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK
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9
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Sensing and Regulating Synaptic Activity by Astrocytes at Tripartite Synapse. Neurochem Res 2021; 46:2580-2585. [PMID: 33837868 PMCID: PMC10159683 DOI: 10.1007/s11064-021-03317-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 03/27/2021] [Accepted: 03/29/2021] [Indexed: 12/11/2022]
Abstract
Astrocytes are recognized as more important cells than historically thought in synaptic function through the reciprocal exchange of signaling with the neuronal synaptic elements. The idea that astrocytes are active elements in synaptic physiology is conceptualized in the Tripartite Synapse concept. This review article presents and discusses recent representative examples that highlight the heterogeneity of signaling in tripartite synapse function and its consequences on neural network function and animal behavior.
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10
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King AC, Wood TE, Rodriguez E, Parpura V, Gray M. Differential effects of SNARE-dependent gliotransmission on behavioral phenotypes in a mouse model of Huntington's disease. Exp Neurol 2020; 330:113358. [PMID: 32387649 PMCID: PMC7313419 DOI: 10.1016/j.expneurol.2020.113358] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 04/14/2020] [Accepted: 05/05/2020] [Indexed: 01/31/2023]
Abstract
Huntington's disease (HD) is a dominantly inherited neurodegenerative disease caused by a polyglutamine expansion in the widely expressed huntingtin protein. Multiple studies have indicated the importance of mutant huntingtin (mHTT) in astrocytes to HD pathogenesis. Astrocytes exhibit SNARE-dependent exocytosis and gliotransmission, which can be hampered by transgenic expression of dominant negative SNARE (dnSNARE) in these glial cells. We used BACHD mice and crossed them with the dnSNARE model to determine if pan-astrocytic SNARE-dependent exocytosis plays an important role in vivo in the progression of HD behavioral phenotypes. We assessed motor and neuropsychiatric behaviors in these mice. At 12 months of age there was a significant improvement in motor coordination (rotarod test) in BACHD/dnSNARE mice when compared to BACHD mice. Analyses of open field performance revealed significant worsening of center entry (at 9 and 12 months), but not distance traveled in BACHD/dnSNARE when compared to BACHD mice, and variable/inconclusive results on vertical plane entry. While no differences between BACHD and BACHD/dnSNARE mice at 12 months of age in the forced swim test were found, we did observe a significant decrease in performance of BACHD/dnSNARE mice in the light-dark box paradigm. Thus, reduction of astrocytic SNARE-dependent exocytosis has differential effects on the psychiatric-like and motor phenotypes observed in BACHD mice. These data suggest broadly targeting SNARE-dependent exocytosis in astrocytes throughout the brain as a means to modulate gliotransmission in HD may contribute to worsening of specific behavioral deficits and perhaps a brain-region specific approach would be required.
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Affiliation(s)
- Annesha C King
- Graduate Biomedical Sciences Neuroscience Theme, University of Alabama at Birmingham, Birmingham, AL, USA; Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama, Birmingham, AL, USA
| | - Tara E Wood
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama, Birmingham, AL, USA
| | - Efrain Rodriguez
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama, Birmingham, AL, USA
| | - Vladimir Parpura
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Michelle Gray
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama, Birmingham, AL, USA; Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA.
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11
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Broadhead MJ, Miles GB. Bi-Directional Communication Between Neurons and Astrocytes Modulates Spinal Motor Circuits. Front Cell Neurosci 2020; 14:30. [PMID: 32180706 PMCID: PMC7057799 DOI: 10.3389/fncel.2020.00030] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 02/03/2020] [Indexed: 01/22/2023] Open
Abstract
Evidence suggests that astrocytes are not merely supportive cells in the nervous system but may actively participate in the control of neural circuits underlying cognition and behavior. In this study, we examined the role of astrocytes within the motor circuitry of the mammalian spinal cord. Pharmacogenetic manipulation of astrocytic activity in isolated spinal cord preparations obtained from neonatal mice revealed astrocyte-derived, adenosinergic modulation of the frequency of rhythmic output generated by the locomotor central pattern generator (CPG) network. Live Ca2+ imaging demonstrated increased activity in astrocytes during locomotor-related output and in response to the direct stimulation of spinal neurons. Finally, astrocytes were found to respond to neuronally-derived glutamate in a metabotropic glutamate receptor 5 (mGluR5) dependent manner, which in turn drives astrocytic modulation of the locomotor network. Our work identifies bi-directional signaling mechanisms between neurons and astrocytes underlying modulatory feedback control of motor circuits, which may act to constrain network output within optimal ranges for movement.
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Affiliation(s)
- Matthew J Broadhead
- School of Psychology and Neuroscience, University of St Andrews, St Andrews, United Kingdom
| | - Gareth B Miles
- School of Psychology and Neuroscience, University of St Andrews, St Andrews, United Kingdom
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12
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Okura U, Hirashima N, Tanaka M. Calcineurin B1 Deficiency in Glial Cells Reduces Gastrointestinal Motility and Results in Maldigestion and/or Malabsorption in Mice. Biol Pharm Bull 2019; 42:1230-1235. [PMID: 31257299 DOI: 10.1248/bpb.b19-00124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Calcineurin is a Ca2+/calmodulin-dependent protein phosphatase abundantly expressed in the nervous system. To investigate the roles of calcineurin in glial cells, we previously generated glial calcineurin B1-conditional knockout (CKO) mice and found that these mice displayed dysfunction of enteric glial cells, mucosal degeneration and inflammation in the small intestine, and growth retardation and postweaning death, suggesting a novel role of calcineurin in enteric glial cells. Although these findings raised a possibility that abnormalities in calcineurin B1-deficient enteric glial cells may cause dysregulation of gastrointestinal motility and result in maldigestion and/or malabsorption in the CKO mice, these issues remain to be elucidated. In the present study, we showed that gastrointestinal motility was reduced in the CKO mice. Degeneration of mucosal epithelium was observed in the small intestine. Glucose levels were decreased in serum, whereas starch, glucose, and lipid levels were increased in feces. Thus, calcineurin B1 deficiency in glial cells reduces gastrointestinal motility, induces mucosal epithelium degeneration in the small intestine, and results in maldigestion and/or malabsorption in mice, further supporting the important role of calcineurin in enteric glial cells.
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Affiliation(s)
- Umi Okura
- Department of Cellular Biophysics, Graduate School of Pharmaceutical Sciences, Nagoya City University
| | - Naohide Hirashima
- Department of Cellular Biophysics, Graduate School of Pharmaceutical Sciences, Nagoya City University
| | - Masahiko Tanaka
- Department of Cellular Biophysics, Graduate School of Pharmaceutical Sciences, Nagoya City University
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13
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Boesmans W, Hao MM, Fung C, Li Z, Van den Haute C, Tack J, Pachnis V, Vanden Berghe P. Structurally defined signaling in neuro-glia units in the enteric nervous system. Glia 2019; 67:1167-1178. [PMID: 30730592 PMCID: PMC6593736 DOI: 10.1002/glia.23596] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 01/11/2019] [Accepted: 01/11/2019] [Indexed: 12/21/2022]
Abstract
Coordination of gastrointestinal function relies on joint efforts of enteric neurons and glia, whose crosstalk is vital for the integration of their activity. To investigate the signaling mechanisms and to delineate the spatial aspects of enteric neuron-to-glia communication within enteric ganglia we developed a method to stimulate single enteric neurons while monitoring the activity of neighboring enteric glial cells. We combined cytosolic calcium uncaging of individual enteric neurons with calcium imaging of enteric glial cells expressing a genetically encoded calcium indicator and demonstrate that enteric neurons signal to enteric glial cells through pannexins using paracrine purinergic pathways. Sparse labeling of enteric neurons and high-resolution analysis of the structural relation between neuronal cell bodies, varicose release sites and enteric glia uncovered that this form of neuron-to-glia communication is contained between the cell body of an enteric neuron and its surrounding enteric glial cells. Our results reveal the spatial and functional foundation of neuro-glia units as an operational cellular assembly in the enteric nervous system.
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Affiliation(s)
- Werend Boesmans
- Laboratory for Enteric NeuroScience (LENS), Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium.,Department of Pathology, GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht, The Netherlands.,Biomedical Research Institute (BIOMED), Hasselt University, Hasselt, Belgium
| | - Marlene M Hao
- Laboratory for Enteric NeuroScience (LENS), Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium.,Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, Australia
| | - Candice Fung
- Laboratory for Enteric NeuroScience (LENS), Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Zhiling Li
- Laboratory for Enteric NeuroScience (LENS), Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Chris Van den Haute
- Laboratory for Neurobiology and Gene Therapy, Department of Neurosciences, University of Leuven, Leuven, Belgium.,Leuven Viral Vector Core, University of Leuven, Leuven, Belgium
| | - Jan Tack
- Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - Vassilis Pachnis
- Development and Homeostasis of the Nervous System Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Pieter Vanden Berghe
- Laboratory for Enteric NeuroScience (LENS), Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
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14
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Grubišić V, Verkhratsky A, Zorec R, Parpura V. Enteric glia regulate gut motility in health and disease. Brain Res Bull 2018; 136:109-117. [PMID: 28363846 PMCID: PMC5620110 DOI: 10.1016/j.brainresbull.2017.03.011] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 02/20/2017] [Accepted: 03/28/2017] [Indexed: 12/16/2022]
Abstract
The enteric nervous system, often referred to as the second brain, is the largest assembly of neurons and glia outside the central nervous system. The enteric nervous system resides within the wall of the digestive tract and regulates local gut reflexes involved in gastrointestinal motility and fluid transport; these functions can be accomplished in the absence of the extrinsic innervation from the central nervous system. It is neurons and their circuitry within the enteric nervous system that govern the gut reflexes. However, it is becoming clear that enteric glial cells are also actively involved in this process through the bidirectional signaling with neurons and other cells in the gut wall. We synthesize the recently discovered modulatory roles of enteric gliotransmission in gut motility and provide our perspective for future lines of research.
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Affiliation(s)
- Vladimir Grubišić
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA; Neuroscience Program, Department of Physiology, Michigan State University, 567 Wilson Road, East Lansing, MI, 48824, USA
| | - Alexei Verkhratsky
- The University of Manchester, Manchester, UK; Achucarro Center for Neuroscience, IKERBASQUE, Basque Foundation for Science, 48011, Bilbao, Spain
| | - Robert Zorec
- Laboratory of Neuroendocrinology-Molecular Cell Physiology, Faculty of Medicine, Institute of Pathophysiology University of Ljubljana, Ljubljana, Slovenia; Celica BIOMEDICAL, Ljubljana, Slovenia
| | - Vladimir Parpura
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA.
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