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Hong S, Lee J, Moon J, Kong E, Jeon J, Kim YS, Kim HR, Kim P. Intravital longitudinal cellular visualization of oral mucosa in a murine model based on rotatory side-view confocal endomicroscopy. BIOMEDICAL OPTICS EXPRESS 2022; 13:4160-4174. [PMID: 36032579 PMCID: PMC9408257 DOI: 10.1364/boe.462269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 06/21/2022] [Accepted: 06/25/2022] [Indexed: 06/15/2023]
Abstract
Oral mucosa is a soft tissue lining the inside of the mouth, protecting the oral cavity from microbiological insults. The mucosal immune system is composed of diverse types of cells that defend against a wide range of pathogens. The pathophysiology of various oral mucosal diseases has been studied mostly by ex vivo histological analysis of harvested specimens. However, to analyze dynamic cellular processes in the oral mucosa, longitudinal in vivo observation of the oral mucosa in a single mouse during pathogenesis is a highly desirable and efficient approach. Herein, by utilizing micro GRIN lens-based rotatory side-view confocal endomicroscopy, we demonstrated non-invasive longitudinal cellular-level in vivo imaging of the oral mucosa, visualizing fluorescently labeled cells including various immune cells, pericytes, nerve cells, and lymphatic and vascular endothelial cells. With rotational and sliding movement of the side-view endomicroscope on the oral mucosa, we successfully achieved a multi-color wide-area cellular-level visualization in a noninvasive manner. By using a transgenic mouse expressing photoconvertible protein, Kaede, we achieved longitudinal repetitive imaging of the same microscopic area in the buccal mucosa of a single mouse for up to 10 days. Finally, we performed longitudinal intravital visualization of the oral mucosa in a DNFB-derived oral contact allergy mouse model, which revealed highly dynamic spatiotemporal changes of CSF1R or LysM expressing immune cells such as monocytes, macrophages, and granulocytes in response to allergic challenge for one week. This technique can be a useful tool to investigate the complex pathophysiology of oral mucosal diseases.
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Affiliation(s)
- Sujung Hong
- Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
- KI for Health Science and Technology (KIHST), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
| | - Jingu Lee
- Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
- KI for Health Science and Technology (KIHST), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
| | - Jieun Moon
- Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
- KI for Health Science and Technology (KIHST), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
| | - Eunji Kong
- KI for Health Science and Technology (KIHST), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
| | - Jehwi Jeon
- KI for Health Science and Technology (KIHST), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
| | - Yeon soo Kim
- Department of Otorhinolaryngology, Konyang University College of Medicine, Konyang University Hospital, Daejeon, 35365, Republic of Korea
| | - Hyung-Ryong Kim
- Department of Pharmacology, College of Dentistry, Jeonbuk National University, Jeonju, 54896, Republic of Korea
| | - Pilhan Kim
- Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
- KI for Health Science and Technology (KIHST), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
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2
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Gorzo KA, Gordon GR. Photonics tools begin to clarify astrocyte calcium transients. NEUROPHOTONICS 2022; 9:021907. [PMID: 35211642 PMCID: PMC8857908 DOI: 10.1117/1.nph.9.2.021907] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 02/01/2022] [Indexed: 05/27/2023]
Abstract
Astrocytes integrate information from neurons and the microvasculature to coordinate brain activity and metabolism. Using a variety of calcium-dependent cellular mechanisms, these cells impact numerous aspects of neurophysiology in health and disease. Astrocyte calcium signaling is highly diverse, with complex spatiotemporal features. Here, we review astrocyte calcium dynamics and the optical imaging tools used to measure and analyze these events. We briefly cover historical calcium measurements, followed by our current understanding of how calcium transients relate to the structure of astrocytes. We then explore newer photonics tools including super-resolution techniques and genetically encoded calcium indicators targeted to specific cellular compartments and how these have been applied to astrocyte biology. Finally, we provide a brief overview of analysis software used to accurately quantify the data and ultimately aid in our interpretation of the various functions of astrocyte calcium transients.
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Affiliation(s)
- Kelsea A. Gorzo
- University of Calgary, Hotchkiss Brain Institute, Cumming School of Medicine, Calgary, Alberta, Canada
| | - Grant R. Gordon
- University of Calgary, Hotchkiss Brain Institute, Cumming School of Medicine, Calgary, Alberta, Canada
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3
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Astrocyte-neuron signaling in the mesolimbic dopamine system: the hidden stars of dopamine signaling. Neuropsychopharmacology 2021; 46:1864-1872. [PMID: 34253855 PMCID: PMC8429665 DOI: 10.1038/s41386-021-01090-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 06/14/2021] [Accepted: 06/28/2021] [Indexed: 02/06/2023]
Abstract
Astrocytes are fundamental components of brain information processing and possess the ability to respond to synaptic signaling with increases in cytoplasmic calcium and modulate neuronal activity with the subsequent release of neuroactive transmitters. Dopamine signaling is essential for brain physiology and pathology, participating in learning and memory, motor control, neurological diseases, and psychiatric diseases, and astrocytes are emerging as a key cellular target of dopamine signaling. The present review will examine evidence revealing that astrocytes respond to dopamine and modulate information processing in the primary brain regions implicated in the mesolimbic dopamine system. Astrocytes exhibit circuit-specific modulation of neuronal networks and have the potential to serve as a therapeutic target for interventions designed for dopamine pathologies.
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4
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Fabbri R, Saracino E, Treossi E, Zamboni R, Palermo V, Benfenati V. Graphene glial-interfaces: challenges and perspectives. NANOSCALE 2021; 13:4390-4407. [PMID: 33599662 DOI: 10.1039/d0nr07824g] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Graphene nanosheets are mechanically strong but flexible, electrically conductive and bio-compatible. Thus, due to these unique properties, they are being intensively studied as materials for the next generation of neural interfaces. Most of the literature focused on optimizing the interface between these materials and neurons. However, one of the most common causes of implant failure is the adverse inflammatory reaction of glial cells. These cells are not, as previously considered, just passive and supportive cells, but play a crucial role in the physiology and pathology of the nervous system, and in the interaction with implanted electrodes. Besides providing structural support to neurons, glia are responsible for the modulation of synaptic transmission and control of central and peripheral homeostasis. Accordingly, knowledge on the interaction between glia and biomaterials is essential to develop new implant-based therapies for the treatment of neurological disorders, such as epilepsy, brain tumours, and Alzheimer's and Parkinson's disease. This work provides an overview of the emerging literature on the interaction of graphene-based materials with glial cells, together with a complete description of the different types of glial cells and problems associated with them. We believe that this description will be important for researchers working in materials science and nanotechnology to develop new active materials to interface, measure and stimulate these cells.
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Affiliation(s)
- Roberta Fabbri
- Consiglio Nazionale delle Ricerche, Istituto per la Sintesi Organica e la Fotoreattività (CNR-ISOF), via Piero Gobetti 101, 40129 Bologna, Italy.
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5
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Iijima K, Oshima T, Kawakami R, Nemoto T. Optical clearing of living brains with MAGICAL to extend i n vivo imaging. iScience 2021; 24:101888. [PMID: 33364578 PMCID: PMC7750414 DOI: 10.1016/j.isci.2020.101888] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 10/02/2020] [Accepted: 11/26/2020] [Indexed: 12/16/2022] Open
Abstract
To understand brain functions, it is important to observe directly how multiple neural circuits are performing in living brains. However, due to tissue opaqueness, observable depth and spatiotemporal resolution are severely degraded in vivo. Here, we propose an optical brain clearing method for in vivo fluorescence microscopy, termed MAGICAL (magical additive glycerol improves clear alive luminance). MAGICAL enabled two-photon microscopy to capture vivid images with fast speed, at cortical layer V and hippocampal CA1 in vivo. Moreover, MAGICAL promoted conventional confocal microscopy to visualize finer neuronal structures including synaptic boutons and spines in unprecedented deep regions, without intensive illumination leading to phototoxic effects. Fluorescence emission spectrum transmissive analysis showed that MAGICAL improved in vivo transmittance of shorter wavelength light, which is vulnerable to optical scattering, thus unsuited for in vivo microscopy. These results suggest that MAGICAL would transparentize living brains via scattering reduction. Oral glycerol administration (MAGICAL) enhances fluorescent signals in living brains MAGICAL achieves in vivo optical clearing for living brains via scattering reduction MAGICAL enables in vivo microscopy to observe brains faster, deeper, and more finely
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Affiliation(s)
- Kouichirou Iijima
- Research Institute for Electronic Science, Hokkaido University, N20W10, Kita-ku, Sapporo, Hokkaido 001-0020, Japan
| | - Takuto Oshima
- Graduate School of Information Science and Technology, Hokkaido University, N14W9, Kita-ku, Sapporo, Hokkaido 060-0814, Japan
| | - Ryosuke Kawakami
- Research Institute for Electronic Science, Hokkaido University, N20W10, Kita-ku, Sapporo, Hokkaido 001-0020, Japan.,Graduate School of Information Science and Technology, Hokkaido University, N14W9, Kita-ku, Sapporo, Hokkaido 060-0814, Japan
| | - Tomomi Nemoto
- Research Institute for Electronic Science, Hokkaido University, N20W10, Kita-ku, Sapporo, Hokkaido 001-0020, Japan.,Graduate School of Information Science and Technology, Hokkaido University, N14W9, Kita-ku, Sapporo, Hokkaido 060-0814, Japan.,Division of Biophotonics, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Higashiyama 5-1, Myodaiji, Okazaki 444-0865, Aichi, Japan.,Biophotonics Research Group, Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Higashiyama 5-1, Myodaiji, Okazaki, Aichi 444-8787, Japan.,School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Higashiyama 5-1, Myodaiji, Okazaki, Aichi 444-8787, Japan
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6
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Carrier M, Robert MÈ, González Ibáñez F, Desjardins M, Tremblay MÈ. Imaging the Neuroimmune Dynamics Across Space and Time. Front Neurosci 2020; 14:903. [PMID: 33071723 PMCID: PMC7539119 DOI: 10.3389/fnins.2020.00903] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 08/04/2020] [Indexed: 12/13/2022] Open
Abstract
The immune system is essential for maintaining homeostasis, as well as promoting growth and healing throughout the brain and body. Considering that immune cells respond rapidly to changes in their microenvironment, they are very difficult to study without affecting their structure and function. The advancement of non-invasive imaging methods greatly contributed to elucidating the physiological roles performed by immune cells in the brain across stages of the lifespan and contexts of health and disease. For instance, techniques like two-photon in vivo microscopy were pivotal for studying microglial functional dynamics in the healthy brain. Through these observations, their interactions with neurons, astrocytes, blood vessels and synapses were uncovered. High-resolution electron microscopy with immunostaining and 3D-reconstruction, as well as super-resolution fluorescence microscopy, provided complementary insights by revealing microglial interventions at synapses (phagocytosis, trogocytosis, synaptic stripping, etc.). In addition, serial block-face scanning electron microscopy has provided the first 3D reconstruction of a microglial cell at nanoscale resolution. This review will discuss the technical toolbox that currently allows to study microglia and other immune cells in the brain, as well as introduce emerging methods that were developed and could be used to increase the spatial and temporal resolution of neuroimmune imaging. A special attention will also be placed on positron emission tomography and the development of selective functional radiotracers for microglia and peripheral macrophages, considering their strong potential for research translation between animals and humans, notably when paired with other imaging modalities such as magnetic resonance imaging.
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Affiliation(s)
- Micaël Carrier
- Axe Neurosciences, Centre de Recherche du CHU de Québec, Université Laval, Québec City, QC, Canada
| | - Marie-Ève Robert
- Axe Neurosciences, Centre de Recherche du CHU de Québec, Université Laval, Québec City, QC, Canada
| | - Fernando González Ibáñez
- Axe Neurosciences, Centre de Recherche du CHU de Québec, Université Laval, Québec City, QC, Canada
| | - Michèle Desjardins
- Axe Oncologie, Centre de Recherche du CHU de Québec, Université Laval, Québec City, QC, Canada.,Department of Physics, Physical Engineering and Optics, Université Laval, Québec City, QC, Canada
| | - Marie-Ève Tremblay
- Axe Neurosciences, Centre de Recherche du CHU de Québec, Université Laval, Québec City, QC, Canada.,Department of Molecular Medicine, Université Laval, Québec City, QC, Canada.,Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
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7
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Pham C, Moro DH, Mouffle C, Didienne S, Hepp R, Pfrieger FW, Mangin JM, Legendre P, Martin C, Luquet S, Cauli B, Li D. Mapping astrocyte activity domains by light sheet imaging and spatio-temporal correlation screening. Neuroimage 2020; 220:117069. [PMID: 32585347 DOI: 10.1016/j.neuroimage.2020.117069] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 06/12/2020] [Accepted: 06/15/2020] [Indexed: 02/08/2023] Open
Abstract
Astrocytes are a major type of glial cell in the mammalian brain, essentially regulating neuronal development and function. Quantitative imaging represents an important approach to study astrocytic signaling in neural circuits. Focusing on astrocytic Ca2+ activity, a key pathway implicated in astrocye-neuron interaction, we here report a strategy combining fast light sheet fluorescence microscopy (LSFM) and correlative screening-based time series analysis, to map activity domains in astrocytes in living mammalian nerve tissue. Light sheet of micron-scale thickness enables wide-field optical sectioning to image astrocytes in acute mouse brain slices. Using both chemical and genetically encoded Ca2+ indicators, we demonstrate the complementary advantages of LSFM in mapping Ca2+ domains in astrocyte populations as compared to epifluorescence and two-photon microscopy. Our approach then revealed distinct kinetics of Ca2+ signals between cortical and hypothalamic astrocytes in resting conditions and following the activation of adrenergic G protein coupled receptor (GPCR). This observation highlights the activity heterogeneity across regionally distinct astrocyte populations, and indicates the potential of our method for investigating dynamic signals in astrocytes.
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Affiliation(s)
- Cuong Pham
- Sorbonne Université, Institute of Biology Paris Seine, Neuroscience Paris Seine, CNRS UMR8246, INSERM U1130, UPMC UMCR18, Paris, 75005, France
| | - Daniela Herrera Moro
- Unité de Biologie Fonctionnelle et Adaptative, Centre National la Recherche Scientifique, Unité Mixte de Recherche 8251, Université Paris Diderot, Sorbonne Paris Cité, 75205, Paris, France
| | - Christine Mouffle
- Sorbonne Université, Institute of Biology Paris Seine, Neuroscience Paris Seine, CNRS UMR8246, INSERM U1130, UPMC UMCR18, Paris, 75005, France
| | - Steve Didienne
- Sorbonne Université, Institute of Biology Paris Seine, Neuroscience Paris Seine, CNRS UMR8246, INSERM U1130, UPMC UMCR18, Paris, 75005, France
| | - Régine Hepp
- Sorbonne Université, Institute of Biology Paris Seine, Neuroscience Paris Seine, CNRS UMR8246, INSERM U1130, UPMC UMCR18, Paris, 75005, France
| | - Frank W Pfrieger
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000, Strasbourg, France
| | - Jean-Marie Mangin
- Sorbonne Université, Institute of Biology Paris Seine, Neuroscience Paris Seine, CNRS UMR8246, INSERM U1130, UPMC UMCR18, Paris, 75005, France
| | - Pascal Legendre
- Sorbonne Université, Institute of Biology Paris Seine, Neuroscience Paris Seine, CNRS UMR8246, INSERM U1130, UPMC UMCR18, Paris, 75005, France
| | - Claire Martin
- Unité de Biologie Fonctionnelle et Adaptative, Centre National la Recherche Scientifique, Unité Mixte de Recherche 8251, Université Paris Diderot, Sorbonne Paris Cité, 75205, Paris, France
| | - Serge Luquet
- Unité de Biologie Fonctionnelle et Adaptative, Centre National la Recherche Scientifique, Unité Mixte de Recherche 8251, Université Paris Diderot, Sorbonne Paris Cité, 75205, Paris, France
| | - Bruno Cauli
- Sorbonne Université, Institute of Biology Paris Seine, Neuroscience Paris Seine, CNRS UMR8246, INSERM U1130, UPMC UMCR18, Paris, 75005, France
| | - Dongdong Li
- Sorbonne Université, Institute of Biology Paris Seine, Neuroscience Paris Seine, CNRS UMR8246, INSERM U1130, UPMC UMCR18, Paris, 75005, France.
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8
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Vicente-Gutierrez C, Bolaños JP. An ex vivo Approach to Assess Mitochondrial ROS by Flow Cytometry in AAV-tagged Astrocytes in Adult Mice. Bio Protoc 2020; 10:e3550. [PMID: 33659524 PMCID: PMC7842736 DOI: 10.21769/bioprotoc.3550] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 01/16/2020] [Accepted: 01/17/2020] [Indexed: 11/02/2022] Open
Abstract
Mitochondrial reactive oxygen species (mROS) are naturally produced signalling molecules extremely relevant for understanding both health- and disease-associated biological processes. The study of mROS in the brain is currently underway to decipher their physiopathological roles and contributions in neurological diseases. Recent advances in this field have highlighted the importance of studying mROS signalling and redox biology at the cellular level. Neurons are especially sensitive to the harmful effects of excess mROS while astrocytic mROS have been shown to play a relevant physiological role in cerebral homeostasis and behaviour. However, given the complexity of the brain, investigating mROS formation in a specific cell-type in adult animals is methodologically challenging. Here we propose an approach to specifically assess mROS abundance in astrocytes that combines i) a targeting strategy based on the use of adeno-associated virus (AAV) vectors expressing the green fluorescent protein (GFP) under an astrocyte (glial fibrillary acidic protein or GFAP) promoter, along with, ii) a robust and widely extended protocol for the measurement of mROS by flow cytometry using commercial probes. The significance of this work is that it allows the selective study of astrocytic mROS abundance by means of easily accessible technology.
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Affiliation(s)
- Carlos Vicente-Gutierrez
- Institute of Functional Biology and Genomics (IBFG), University of Salamanca, CSIC, Salamanca, Spain
- Institute of Biomedical Research of Salamanca (IBSAL), Salamanca, Spain
- CIBERFES, Madrid, Spain
| | - Juan P. Bolaños
- Institute of Functional Biology and Genomics (IBFG), University of Salamanca, CSIC, Salamanca, Spain
- Institute of Biomedical Research of Salamanca (IBSAL), Salamanca, Spain
- CIBERFES, Madrid, Spain
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9
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Droguerre M, Tsurugizawa T, Duchêne A, Portal B, Guiard BP, Déglon N, Rouach N, Hamon M, Mouthon F, Ciobanu L, Charvériat M. A New Tool for In Vivo Study of Astrocyte Connexin 43 in Brain. Sci Rep 2019; 9:18292. [PMID: 31797899 PMCID: PMC6892890 DOI: 10.1038/s41598-019-54858-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 11/20/2019] [Indexed: 01/22/2023] Open
Abstract
Astrocytes are glial cells organized in dynamic and structured networks in the brain. These plastic networks, involving key proteins such as connexin 43 (Cx43), are engaged in fine neuronal tuning and have recently been considered as emerging therapeutic targets in central nervous system disorders. We developed and validated a new application of the manganese-enhanced magnetic resonance imaging (MEMRI) technique allowing in vivo investigations of astrocyte-neuron interactions through quantification of brain Cx43 functional activity. The proof of concept has been achieved by quantification of MEMRI signals in brain after either local astrocyte-specific Cx43 knockdown with shRNA or systemic administration of Cx43 blockers. Unilateral hippocampal Cx43 genetical silencing was associated with an ipsilateral local increase of MEMRI signal. Furthermore, Cx43 blockers also enhanced MEMRI signal responses in hippocampus. Altogether, these data reveal the MEMRI technique as a tool for quantitative imaging of in vivo Cx43-dependent function in astrocytes under physiological and pathological conditions.
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Affiliation(s)
| | | | | | - Benjamin Portal
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31330, Toulouse, France
| | - Bruno P Guiard
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31330, Toulouse, France
| | - Nicole Déglon
- Laboratory of Neurotherapies and NeuroModulation, Neuroscience research Center (CRN), Lausanne University Hospital (CHUV) and University of Lausanne, 1011, Lausanne, Switzerland.,Laboratory of Neurotherapies and NeuroModulation, Department of Clinical Neuroscience (DNC), Lausanne University Hospital (CHUV) and University of Lausanne, 1011, Lausanne, Switzerland
| | - Nathalie Rouach
- Laboratory of Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, 75005, France
| | - Michel Hamon
- Theranexus, 60 Avenue Rockefeller, 69008, Lyon, France
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10
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Synapse-specific astrocyte gating of amygdala-related behavior. Nat Neurosci 2017; 20:1540-1548. [PMID: 28945222 DOI: 10.1038/nn.4649] [Citation(s) in RCA: 185] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 08/30/2017] [Indexed: 12/12/2022]
Abstract
The amygdala plays key roles in fear and anxiety. Studies of the amygdala have largely focused on neuronal function and connectivity. Astrocytes functionally interact with neurons, but their role in the amygdala remains largely unknown. We show that astrocytes in the medial subdivision of the central amygdala (CeM) determine the synaptic and behavioral outputs of amygdala circuits. To investigate the role of astrocytes in amygdala-related behavior and identify the underlying synaptic mechanisms, we used exogenous or endogenous signaling to selectively activate CeM astrocytes. Astrocytes depressed excitatory synapses from basolateral amygdala via A1 adenosine receptor activation and enhanced inhibitory synapses from the lateral subdivision of the central amygdala via A2A receptor activation. Furthermore, astrocytic activation decreased the firing rate of CeM neurons and reduced fear expression in a fear-conditioning paradigm. Therefore, we conclude that astrocyte activity determines fear responses by selectively regulating specific synapses, which indicates that animal behavior results from the coordinated activity of neurons and astrocytes.
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11
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Fernandez AM, Hernandez-Garzón E, Perez-Domper P, Perez-Alvarez A, Mederos S, Matsui T, Santi A, Trueba-Saiz A, García-Guerra L, Pose-Utrilla J, Fielitz J, Olson EN, Fernandez de la Rosa R, Garcia Garcia L, Pozo MA, Iglesias T, Araque A, Soya H, Perea G, Martin ED, Torres Aleman I. Insulin Regulates Astrocytic Glucose Handling Through Cooperation With IGF-I. Diabetes 2017; 66:64-74. [PMID: 27999108 DOI: 10.2337/db16-0861] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 09/28/2016] [Indexed: 11/13/2022]
Abstract
Brain activity requires a flux of glucose to active regions to sustain increased metabolic demands. Insulin, the main regulator of glucose handling in the body, has been traditionally considered not to intervene in this process. However, we now report that insulin modulates brain glucose metabolism by acting on astrocytes in concert with IGF-I. The cooperation of insulin and IGF-I is needed to recover neuronal activity after hypoglycemia. Analysis of underlying mechanisms show that the combined action of IGF-I and insulin synergistically stimulates a mitogen-activated protein kinase/protein kinase D pathway resulting in translocation of GLUT1 to the cell membrane through multiple protein-protein interactions involving the scaffolding protein GAIP-interacting protein C terminus and the GTPase RAC1. Our observations identify insulin-like peptides as physiological modulators of brain glucose handling, providing further support to consider the brain as a target organ in diabetes.
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Affiliation(s)
- Ana M Fernandez
- Cajal Institute, Consejo Superior de Investigaciones Científicas, Madrid, Spain
- CIBERNED, Madrid, Spain
| | - Edwin Hernandez-Garzón
- Cajal Institute, Consejo Superior de Investigaciones Científicas, Madrid, Spain
- CIBERNED, Madrid, Spain
| | - Paloma Perez-Domper
- Cajal Institute, Consejo Superior de Investigaciones Científicas, Madrid, Spain
- CIBERNED, Madrid, Spain
| | - Alberto Perez-Alvarez
- Cajal Institute, Consejo Superior de Investigaciones Científicas, Madrid, Spain
- Center for Molecular Neurobiology Hamburg, Hamburg, Germany
| | - Sara Mederos
- Cajal Institute, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Takashi Matsui
- Laboratory of Exercise Biochemistry and Neuroendocrinology, University of Tsukuba, Tsukuba, Japan
| | - Andrea Santi
- Cajal Institute, Consejo Superior de Investigaciones Científicas, Madrid, Spain
- CIBERNED, Madrid, Spain
| | - Angel Trueba-Saiz
- Cajal Institute, Consejo Superior de Investigaciones Científicas, Madrid, Spain
- CIBERNED, Madrid, Spain
| | - Lucía García-Guerra
- CIBERNED, Madrid, Spain
- Instituto de Investigaciones Biomédicas "Alberto Sols," Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain
| | - Julia Pose-Utrilla
- CIBERNED, Madrid, Spain
- Instituto de Investigaciones Biomédicas "Alberto Sols," Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain
| | - Jens Fielitz
- Experimental and Clinical Research Center, Charité-Universitätsmedizin, Max Delbrück Center for Molecular Medicine, Berlin, Germany
- Brandenburg Heart Center and Medical University of Brandenburg, Brandenburg, Germany
| | - Eric N Olson
- University of Texas Southwestern Medical Center, Dallas, TX
| | | | - Luis Garcia Garcia
- Pluridisciplinary Institute, Complutense University of Madrid, Madrid, Spain
| | - Miguel Angel Pozo
- Pluridisciplinary Institute, Complutense University of Madrid, Madrid, Spain
| | - Teresa Iglesias
- CIBERNED, Madrid, Spain
- Instituto de Investigaciones Biomédicas "Alberto Sols," Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain
| | - Alfonso Araque
- Cajal Institute, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Hideaki Soya
- Laboratory of Exercise Biochemistry and Neuroendocrinology, University of Tsukuba, Tsukuba, Japan
| | - Gertrudis Perea
- Cajal Institute, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Eduardo D Martin
- Science and Technology Park, Institute for Research in Neurological Disabilities, University of Castilla-La Mancha, Albacete, Spain
| | - Ignacio Torres Aleman
- Cajal Institute, Consejo Superior de Investigaciones Científicas, Madrid, Spain
- CIBERNED, Madrid, Spain
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12
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Hernandez-Garzón E, Fernandez AM, Perez-Alvarez A, Genis L, Bascuñana P, Fernandez de la Rosa R, Delgado M, Angel Pozo M, Moreno E, McCormick PJ, Santi A, Trueba-Saiz A, Garcia-Caceres C, Tschöp MH, Araque A, Martin ED, Torres Aleman I. The insulin-like growth factor I receptor regulates glucose transport by astrocytes. Glia 2016; 64:1962-71. [PMID: 27462832 DOI: 10.1002/glia.23035] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 07/05/2016] [Accepted: 07/07/2016] [Indexed: 12/20/2022]
Abstract
Previous findings indicate that reducing brain insulin-like growth factor I receptor (IGF-IR) activity promotes ample neuroprotection. We now examined a possible action of IGF-IR on brain glucose transport to explain its wide protective activity, as energy availability is crucial for healthy tissue function. Using (18) FGlucose PET we found that shRNA interference of IGF-IR in mouse somatosensory cortex significantly increased glucose uptake upon sensory stimulation. In vivo microscopy using astrocyte specific staining showed that after IGF-IR shRNA injection in somatosensory cortex, astrocytes displayed greater increases in glucose uptake as compared to astrocytes in the scramble-injected side. Further, mice with the IGF-IR knock down in astrocytes showed increased glucose uptake in somatosensory cortex upon sensory stimulation. Analysis of underlying mechanisms indicated that IGF-IR interacts with glucose transporter 1 (GLUT1), the main facilitative glucose transporter in astrocytes, through a mechanism involving interactions with the scaffolding protein GIPC and the multicargo transporter LRP1 to retain GLUT1 inside the cell. These findings identify IGF-IR as a key modulator of brain glucose metabolism through its inhibitory action on astrocytic GLUT1 activity. GLIA 2016;64:1962-1971.
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Affiliation(s)
| | | | - Alberto Perez-Alvarez
- Cajal Institute, CSIC, Madrid, Spain.,Center for Molecular Neurobiology Hamburg, Hamburg, Germany
| | - Laura Genis
- Cajal Institute, CSIC, Madrid, Spain.,Ciberned, Spain
| | - Pablo Bascuñana
- Pluridisciplinary Institute, Complutense University, Madrid, Spain
| | | | - Mercedes Delgado
- Pluridisciplinary Institute, Complutense University, Madrid, Spain
| | | | - Estefania Moreno
- Ciberned, Spain.,Dept Biochemistry and Molecular Biology, University of Barcelona, Barcelona, Spain
| | - Peter J McCormick
- Ciberned, Spain.,Dept Biochemistry and Molecular Biology, University of Barcelona, Barcelona, Spain.,School of Pharmacy, University of East Anglia, Norwich, Norfolk, United Kingdom
| | - Andrea Santi
- Cajal Institute, CSIC, Madrid, Spain.,Ciberned, Spain
| | | | | | | | | | - Eduardo D Martin
- Science and Technology Park, Institute for Research in Neurological Disabilities, University of Castilla-La Mancha, Albacete, Spain
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13
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Retinal Macroglial Responses in Health and Disease. BIOMED RESEARCH INTERNATIONAL 2016; 2016:2954721. [PMID: 27294114 PMCID: PMC4887628 DOI: 10.1155/2016/2954721] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 04/14/2016] [Indexed: 12/20/2022]
Abstract
Due to their permanent and close proximity to neurons, glial cells perform essential tasks for the normal physiology of the retina. Astrocytes and Müller cells (retinal macroglia) provide physical support to neurons and supplement them with several metabolites and growth factors. Macroglia are involved in maintaining the homeostasis of extracellular ions and neurotransmitters, are essential for information processing in neural circuits, participate in retinal glucose metabolism and in removing metabolic waste products, regulate local blood flow, induce the blood-retinal barrier (BRB), play fundamental roles in local immune response, and protect neurons from oxidative damage. In response to polyetiological insults, glia cells react with a process called reactive gliosis, seeking to maintain retinal homeostasis. When malfunctioning, macroglial cells can become primary pathogenic elements. A reactive gliosis has been described in different retinal pathologies, including age-related macular degeneration (AMD), diabetes, glaucoma, retinal detachment, or retinitis pigmentosa. A better understanding of the dual, neuroprotective, or cytotoxic effect of macroglial involvement in retinal pathologies would help in treating the physiopathology of these diseases. The extensive participation of the macroglia in retinal diseases points to these cells as innovative targets for new drug therapies.
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14
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Reciprocal Regulation of Mitochondrial Dynamics and Calcium Signaling in Astrocyte Processes. J Neurosci 2016; 35:15199-213. [PMID: 26558789 DOI: 10.1523/jneurosci.2049-15.2015] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED We recently showed that inhibition of neuronal activity, glutamate uptake, or reversed-Na(+)/Ca(2+)-exchange with TTX, TFB-TBOA, or YM-244769, respectively, increases mitochondrial mobility in astrocytic processes. In the present study, we examined the interrelationships between mitochondrial mobility and Ca(2+) signaling in astrocyte processes in organotypic cultures of rat hippocampus. All of the treatments that increase mitochondrial mobility decreased basal Ca(2+). As recently reported, we observed spontaneous Ca(2+) spikes with half-lives of ∼1 s that spread ∼6 μm and are almost abolished by a TRPA1 channel antagonist. Virtually all of these Ca(2+) spikes overlap mitochondria (98%), and 62% of mitochondria are overlapped by these spikes. Although tetrodotoxin, TFB-TBOA, or YM-244769 increased Ca(2+) signaling, the specific effects on peak, decay time, and/or frequency were different. To more specifically manipulate mitochondrial mobility, we explored the effects of Miro motor adaptor proteins. We show that Miro1 and Miro2 are both expressed in astrocytes and that exogenous expression of Ca(2+)-insensitive Miro mutants (KK) nearly doubles the percentage of mobile mitochondria. Expression of Miro1(KK) had a modest effect on the frequency of these Ca(2+) spikes but nearly doubled the decay half-life. The mitochondrial proton ionophore, FCCP, caused a large, prolonged increase in cytosolic Ca(2+) followed by an increase in the decay time and the spread of the spontaneous Ca(2+) spikes. Photo-ablation of mitochondria in individual astrocyte processes has similar effects on Ca(2+). Together, these studies show that Ca(2+) regulates mitochondrial mobility, and mitochondria in turn regulate Ca(2+) signals in astrocyte processes. SIGNIFICANCE STATEMENT In neurons, the movement and positioning of mitochondria at sites of elevated activity are important for matching local energy and Ca(2+) buffering capacity. Previously, we demonstrated that mitochondria are immobilized in astrocytes in response to neuronal activity and glutamate uptake. Here, we demonstrate a mechanism by which mitochondria are immobilized in astrocytes subsequent to increases in intracellular [Ca(2+)] and provide evidence that mitochondria contribute to the compartmentalization of spontaneous Ca(2+) signals in astrocyte processes. Immobilization of mitochondria at sites of glutamate uptake in astrocyte processes provides a mechanism to coordinate increases in activity with increases in mitochondrial metabolism.
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15
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Follain G, Mercier L, Osmani N, Harlepp S, Goetz JG. Seeing is believing: multi-scale spatio-temporal imaging towards in vivo cell biology. J Cell Sci 2016; 130:23-38. [DOI: 10.1242/jcs.189001] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
ABSTRACT
Life is driven by a set of biological events that are naturally dynamic and tightly orchestrated from the single molecule to entire organisms. Although biochemistry and molecular biology have been essential in deciphering signaling at a cellular and organismal level, biological imaging has been instrumental for unraveling life processes across multiple scales. Imaging methods have considerably improved over the past decades and now allow to grasp the inner workings of proteins, organelles, cells, organs and whole organisms. Not only do they allow us to visualize these events in their most-relevant context but also to accurately quantify underlying biomechanical features and, so, provide essential information for their understanding. In this Commentary, we review a palette of imaging (and biophysical) methods that are available to the scientific community for elucidating a wide array of biological events. We cover the most-recent developments in intravital imaging, light-sheet microscopy, super-resolution imaging, and correlative light and electron microscopy. In addition, we illustrate how these technologies have led to important insights in cell biology, from the molecular to the whole-organism resolution. Altogether, this review offers a snapshot of the current and state-of-the-art imaging methods that will contribute to the understanding of life and disease.
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Affiliation(s)
- Gautier Follain
- Microenvironmental Niche in Tumorigenesis and Targeted Therapy, Inserm U1109, MN3T, Strasbourg F-67200, France
- Université de Strasbourg, Strasbourg F-67000, France
- LabEx Medalis, Université de Strasbourg, Strasbourg, F-67000, France
- Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg F-67000, France
| | - Luc Mercier
- Microenvironmental Niche in Tumorigenesis and Targeted Therapy, Inserm U1109, MN3T, Strasbourg F-67200, France
- Université de Strasbourg, Strasbourg F-67000, France
- LabEx Medalis, Université de Strasbourg, Strasbourg, F-67000, France
- Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg F-67000, France
| | - Naël Osmani
- Microenvironmental Niche in Tumorigenesis and Targeted Therapy, Inserm U1109, MN3T, Strasbourg F-67200, France
- Université de Strasbourg, Strasbourg F-67000, France
- LabEx Medalis, Université de Strasbourg, Strasbourg, F-67000, France
- Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg F-67000, France
| | - Sébastien Harlepp
- Université de Strasbourg, Strasbourg F-67000, France
- DON: Optique ultrarapide et nanophotonique, IPCMS UMR7504, Strasbourg 67000, France
- LabEx NIE, Université de Strasbourg, Strasbourg F-67000, France
| | - Jacky G. Goetz
- Microenvironmental Niche in Tumorigenesis and Targeted Therapy, Inserm U1109, MN3T, Strasbourg F-67200, France
- Université de Strasbourg, Strasbourg F-67000, France
- LabEx Medalis, Université de Strasbourg, Strasbourg, F-67000, France
- Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg F-67000, France
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16
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Martín R, Bajo-Grañeras R, Moratalla R, Perea G, Araque A. Circuit-specific signaling in astrocyte-neuron networks in basal ganglia pathways. Science 2015; 349:730-4. [PMID: 26273054 DOI: 10.1126/science.aaa7945] [Citation(s) in RCA: 213] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Astrocytes are important regulatory elements in brain function. They respond to neurotransmitters and release gliotransmitters that modulate synaptic transmission. However, the cell- and synapse-specificity of the functional relationship between astrocytes and neurons in certain brain circuits remains unknown. In the dorsal striatum, which mainly comprises two intermingled subtypes (striatonigral and striatopallidal) of medium spiny neurons (MSNs) and synapses belonging to two neural circuits (the direct and indirect pathways of the basal ganglia), subpopulations of astrocytes selectively responded to specific MSN subtype activity. These subpopulations of astrocytes released glutamate that selectively activated N-methyl-d-aspartate receptors in homotypic, but not heterotypic, MSNs. Likewise, astrocyte subpopulations selectively regulated homotypic synapses through metabotropic glutamate receptor activation. Therefore, bidirectional astrocyte-neuron signaling selectively occurs between specific subpopulations of astrocytes, neurons, and synapses.
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Affiliation(s)
- R Martín
- Instituto Cajal, Consejo Superior de Investigaciones Científicas, 28002 Madrid, Spain
| | - R Bajo-Grañeras
- Instituto Cajal, Consejo Superior de Investigaciones Científicas, 28002 Madrid, Spain
| | - R Moratalla
- Instituto Cajal, Consejo Superior de Investigaciones Científicas, 28002 Madrid, Spain. Centro de Investigación Biomédica en Red Enfermedades Neurodegenerativas, Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - G Perea
- Instituto Cajal, Consejo Superior de Investigaciones Científicas, 28002 Madrid, Spain
| | - A Araque
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA.
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17
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Ozbay BN, Losacco JT, Cormack R, Weir R, Bright VM, Gopinath JT, Restrepo D, Gibson EA. Miniaturized fiber-coupled confocal fluorescence microscope with an electrowetting variable focus lens using no moving parts. OPTICS LETTERS 2015; 40:2553-6. [PMID: 26030555 PMCID: PMC4517461 DOI: 10.1364/ol.40.002553] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We report a miniature, lightweight fiber-coupled confocal fluorescence microscope that incorporates an electrowetting variable focus lens to provide axial scanning for full three-dimensional (3D) imaging. Lateral scanning is accomplished by coupling our device to a laser-scanning confocal microscope through a coherent imaging fiber-bundle. The optical components of the device are combined in a custom 3D-printed adapter with an assembled weight of <2 g that can be mounted onto the head of a mouse. Confocal sectioning provides an axial resolution of ∼12 μm and an axial scan range of ∼80 μm. The lateral field-of-view is 300 μm, and the lateral resolution is 1.8 μm. We determined these parameters by imaging fixed sections of mouse neuronal tissue labeled with green fluorescent protein (GFP) and fluorescent bead samples in agarose gel. To demonstrate viability for imaging intact tissue, we resolved multiple optical sections of ex vivo mouse olfactory nerve fibers expressing yellow fluorescent protein (YFP).
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Affiliation(s)
- Baris N. Ozbay
- Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, USA
| | - Justin T. Losacco
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, USA
| | - Robert Cormack
- Department of Electrical, Computer and Energy Engineering, University of Colorado Boulder, Colorado 80309, USA
| | - Richard Weir
- Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, USA
| | - Victor M. Bright
- Department of Mechanical Engineering, University of Colorado Boulder, Colorado 80309, USA
| | - Juliet T. Gopinath
- Department of Electrical, Computer and Energy Engineering, University of Colorado Boulder, Colorado 80309, USA
| | - Diego Restrepo
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, USA
| | - Emily A. Gibson
- Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, USA
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18
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Abstract
Experience-dependent plasticity of synaptic transmission, which represents the cellular basis of learning, is accompanied by morphological changes in dendritic spines. Astrocytic processes are intimately associated with synapses, structurally enwrapping and functionally interacting with dendritic spines and synaptic terminals by responding to neurotransmitters and by releasing gliotransmitters that regulate synaptic function. While studies on structural synaptic plasticity have focused on neuronal elements, the structural-functional plasticity of astrocyte-neuron relationships remains poorly known. Here we show that stimuli inducing hippocampal synaptic LTP enhance the motility of synapse-associated astrocytic processes. This motility increase is relatively rapid, starting <5 min after the stimulus, and reaching a maximum in 20-30 min (t(1/2) = 10.7 min). It depends on presynaptic activity and requires G-protein-mediated Ca(2+) elevations in astrocytes. The structural remodeling is accompanied by changes in the ability of astrocytes to regulate synaptic transmission. Sensory stimuli that increase astrocyte Ca(2+) also induce similar plasticity in mouse somatosensory cortex in vivo. Therefore, structural relationships between astrocytic processes and dendritic spines undergo activity-dependent changes with metaplasticity consequences on synaptic regulation. These results reveal novel forms of synaptic plasticity based on structural-functional changes of astrocyte-neuron interactions.
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19
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Mooney MA, Zehri AH, Georges JF, Nakaji P. Laser scanning confocal endomicroscopy in the neurosurgical operating room: a review and discussion of future applications. Neurosurg Focus 2014; 36:E9. [PMID: 24484262 DOI: 10.3171/2013.11.focus13484] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Laser scanning confocal endomicroscopy (LSCE) is an emerging technology for examining brain neoplasms in vivo. While great advances have been made in macroscopic fluorescence in recent years, the ability to perform confocal microscopy in vivo expands the potential of fluorescent tumor labeling, can improve intraoperative tissue diagnosis, and provides real-time guidance for tumor resection intraoperatively. In this review, the authors highlight the technical aspects of confocal endomicroscopy and fluorophores relevant to the neurosurgeon, provide a comprehensive summary of LSCE in animal and human neurosurgical studies to date, and discuss the future directions and potential for LSCE in neurosurgery.
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20
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Lamantia C, Tremblay ME, Majewska A. Characterization of the BAC Id3-enhanced green fluorescent protein transgenic mouse line for in vivo imaging of astrocytes. NEUROPHOTONICS 2014; 1:011014. [PMID: 26157970 PMCID: PMC4478958 DOI: 10.1117/1.nph.1.1.011014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 08/06/2014] [Accepted: 09/03/2014] [Indexed: 06/04/2023]
Abstract
Astrocytes are highly ramified glial cells with critical roles in brain physiology and pathology. Recently, breakthroughs in imaging technology have expanded our understanding of astrocyte function in vivo. The in vivo study of astrocytic dynamics, however, is limited by the tools available to label astrocytes and their processes. Here, we characterize the bacterial artificial chromosome transgenic Id3-EGFP knock-in mouse to establish its usefulness for in vivo imaging of astrocyte processes. Using fixed brain sections, we observed enhanced green fluorescent protein expression in astrocytes and blood vessel walls throughout the brain, although the extent and cell type specificity of expression depended on the brain area and developmental age. Using in vivo two-photon imaging, we visualized astrocytes in cortical layers 1-3 in both thin skull and window preparations. In adult animals, astrocytic cell bodies and fine processes could be followed over many hours. Our results suggest that Id3 mice could be used for in vivo imaging of astrocytes and blood vessels in development and adulthood.
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Affiliation(s)
- Cassandra Lamantia
- University of Rochester, Department of Neurobiology and Anatomy, Rochester, New York 14642, United States
| | - Marie-Eve Tremblay
- University of Rochester, Department of Neurobiology and Anatomy, Rochester, New York 14642, United States
| | - Ania Majewska
- University of Rochester, Department of Neurobiology and Anatomy, Rochester, New York 14642, United States
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21
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Escartin C, Murai KK. Imaging and monitoring astrocytes in health and disease. Front Cell Neurosci 2014; 8:74. [PMID: 24659954 PMCID: PMC3950414 DOI: 10.3389/fncel.2014.00074] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 02/19/2014] [Indexed: 11/28/2022] Open
Affiliation(s)
- Carole Escartin
- CNRS CEA URA 2210 and CEA, DSV, I2BM, MIRCen Fontenay-aux-Roses, France
| | - Keith K Murai
- Department of Neurology and Neurosurgery, Center for Research in Neuroscience Montreal, Canada
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