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Chae U, Chun H, Lim J, Shin H, Smith WC, Choi JW, Park KD, Lee CJ, Cho IJ. KDS2010, a reversible MAO-B inhibitor, extends the lifetime of neural probes by preventing glial scar formation. Glia 2024; 72:748-758. [PMID: 38200694 DOI: 10.1002/glia.24500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 12/07/2023] [Accepted: 12/19/2023] [Indexed: 01/12/2024]
Abstract
Implantable neural probes have been extensively utilized in the fields of neurocircuitry, systems neuroscience, and brain-computer interface. However, the long-term functionality of these devices is hampered by the formation of glial scar and astrogliosis at the surface of electrodes. In this study, we administered KDS2010, a recently developed reversible MAO-B inhibitor, to mice through ad libitum drinking in order to prevent glial scar formation and astrogliosis. The administration of KDS2010 allowed long-term recordings of neural signals with implantable devices, which remained stable over a period of 6 months and even restored diminished neural signals after probe implantation. KDS2010 effectively prevented the formation of glial scar, which consists of reactive astrocytes and activated microglia around the implant. Furthermore, it restored neural activity by disinhibiting astrocytic MAO-B dependent tonic GABA inhibition induced by astrogliosis. We suggest that the use of KDS2010 is a promising approach to prevent glial scar formation around the implant, thereby enabling long-term functionality of neural devices.
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Affiliation(s)
- Uikyu Chae
- Department of Convergence Medicine, College of Medicine, Korea University, Seoul, Republic of Korea
| | - Heejung Chun
- Yonsei-SLBigen Research Institute, College of Pharmacy, Yonsei University, Incheon, Republic of Korea
| | - Jiwoon Lim
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, Republic of Korea
- IBS School, University of Science and Technology (UST), Daejeon, Republic of Korea
| | - Hyogeun Shin
- Department of Convergence Medicine, College of Medicine, Korea University, Seoul, Republic of Korea
| | - Wesley Charles Smith
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - Ji Won Choi
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - Ki Duk Park
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - C Justin Lee
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, Republic of Korea
- IBS School, University of Science and Technology (UST), Daejeon, Republic of Korea
| | - Il-Joo Cho
- Department of Convergence Medicine, College of Medicine, Korea University, Seoul, Republic of Korea
- Department of Anatomy, College of Medicine, Korea University, Seoul, Republic of Korea
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2
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Mishima T, Komano K, Tabaru M, Kofuji T, Saito A, Ugawa Y, Terao Y. Repetitive pulsed-wave ultrasound stimulation suppresses neural activity by modulating ambient GABA levels via effects on astrocytes. Front Cell Neurosci 2024; 18:1361242. [PMID: 38601023 PMCID: PMC11004293 DOI: 10.3389/fncel.2024.1361242] [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: 12/28/2023] [Accepted: 03/18/2024] [Indexed: 04/12/2024] Open
Abstract
Ultrasound is highly biopermeable and can non-invasively penetrate deep into the brain. Stimulation with patterned low-intensity ultrasound can induce sustained inhibition of neural activity in humans and animals, with potential implications for research and therapeutics. Although mechanosensitive channels are involved, the cellular and molecular mechanisms underlying neuromodulation by ultrasound remain unknown. To investigate the mechanism of action of ultrasound stimulation, we studied the effects of two types of patterned ultrasound on synaptic transmission and neural network activity using whole-cell recordings in primary cultured hippocampal cells. Single-shot pulsed-wave (PW) or continuous-wave (CW) ultrasound had no effect on neural activity. By contrast, although repetitive CW stimulation also had no effect, repetitive PW stimulation persistently reduced spontaneous recurrent burst firing. This inhibitory effect was dependent on extrasynaptic-but not synaptic-GABAA receptors, and the effect was abolished under astrocyte-free conditions. Pharmacological activation of astrocytic TRPA1 channels mimicked the effects of ultrasound by increasing the tonic GABAA current induced by ambient GABA. Pharmacological blockade of TRPA1 channels abolished the inhibitory effect of ultrasound. These findings suggest that the repetitive PW low-intensity ultrasound used in our study does not have a direct effect on neural function but instead exerts its sustained neuromodulatory effect through modulation of ambient GABA levels via channels with characteristics of TRPA1, which is expressed in astrocytes.
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Affiliation(s)
- Tatsuya Mishima
- Department of Medical Physiology, Kyorin University School of Medicine, Mitaka, Japan
| | - Kenta Komano
- Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
| | - Marie Tabaru
- Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
| | - Takefumi Kofuji
- Department of Medical Physiology, Kyorin University School of Medicine, Mitaka, Japan
- Radioisotope Laboratory, Kyorin University School of Medicine, Mitaka, Japan
| | - Ayako Saito
- Department of Medical Physiology, Kyorin University School of Medicine, Mitaka, Japan
| | - Yoshikazu Ugawa
- Department of Human Neurophysiology, School of Medicine, Fukushima Medical University, Fukushima, Japan
| | - Yasuo Terao
- Department of Medical Physiology, Kyorin University School of Medicine, Mitaka, Japan
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3
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Bhalla M, Lee CJ. Long-term inhibition of ODC1 in APP/PS1 mice rescues amyloid pathology and switches astrocytes from a reactive to active state. Mol Brain 2024; 17:3. [PMID: 38216963 PMCID: PMC10785549 DOI: 10.1186/s13041-024-01076-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 01/05/2024] [Indexed: 01/14/2024] Open
Abstract
Alzheimer's disease (AD) is characterized by the loss of memory due to aggregation of misphosphorylated tau and amyloid beta (Aβ) plaques in the brain, elevated release of inhibitory neurotransmitter gamma-aminobutyric acid (GABA) and reactive oxygen species from astrocytes, and subsequent neurodegeneration. Recently, it was found that enzyme Ornithine Decarboxylase 1 (ODC1) acts as a bridge between the astrocytic urea cycle and the putrescine-to-GABA conversion pathway in the brain of AD mouse models as well as human patients. In this study, we show that the long-term knockdown of astrocytic Odc1 in APP/PS1 animals was sufficient to completely clear Aβ plaques in the hippocampus while simultaneously switching the astrocytes from a detrimental reactive state to a regenerative active state, characterized by proBDNF expression. Our experiments also reveal an effect of astrocytic ODC1 inhibition on the expression of genes involved in synapse pruning and organization, histone modification, apoptotic signaling and protein processing. These genes are previously known to be associated with astrocytic activation and together create a neuroregeneration-supportive environment in the brain. By inhibiting ODC1 for a long period of 3 months in AD mice, we demonstrate that the beneficial amyloid-clearing process of astrocytes can be completely segregated from the systemically harmful astrocytic response to insult. Our study reports an almost complete clearance of Aβ plaques by controlling an endogenous degradation process, which also modifies the astrocytic state to create a regeneration-supportive environment in the brain. These findings present the potential of modulating astrocytic clearance of Aβ as a powerful therapeutic strategy against AD.
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Affiliation(s)
- Mridula Bhalla
- Center for Cognition and Sociality, Life Science Institute (LSI), Institute for Basic Science (IBS), 55, Expo-ro, Yuseong-gu, Daejeon, 34126, Republic of Korea
- IBS School, University of Science and Technology (UST), 217 Gajeong-ro, Yuseong-gu, Daejeon, 34113, Republic of Korea
| | - C Justin Lee
- Center for Cognition and Sociality, Life Science Institute (LSI), Institute for Basic Science (IBS), 55, Expo-ro, Yuseong-gu, Daejeon, 34126, Republic of Korea.
- IBS School, University of Science and Technology (UST), 217 Gajeong-ro, Yuseong-gu, Daejeon, 34113, Republic of Korea.
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4
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Jahanbakhshi H, Moghaddam MH, Sani M, Parvardeh S, Boroujeni ME, Vakili K, Fathi M, Azimi H, Mehranpour M, Abdollahifar MA, Ghafghazi S, Sadidi M, Aliaghaei A, Bayat AH, Peyvandi AA. The elderberry diet protection against intrahippocampal Aβ-induced memory dysfunction; the abrogated apoptosis and neuroinflammation. Toxicol Res (Camb) 2023; 12:1063-1076. [PMID: 38145093 PMCID: PMC10734613 DOI: 10.1093/toxres/tfad097] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/31/2023] [Accepted: 10/04/2023] [Indexed: 12/26/2023] Open
Abstract
This study evaluates whether elderberry (EB) effectively decreases the inflammation and oxidative stress in the brain cells to reduce Aβ toxicity. In the Aβ + EB group, EB powder was added to rats' routine diet for eight consecutive weeks. Then, spatial memory, working memory, and long-term memory, were measured using the Morris water maze, T-maze, and passive avoidance test. Also, in this investigation immunohistopathology, distribution of hippocampal cells, and gene expression was carried out. Voronoi tessellation method was used to estimate the spatial distribution of the cells in the hippocampus. In addition to improving the memory functions of rats with Aβ toxicity, a reduction in astrogliosis and astrocytes process length and the number of branches and intersections distal to the soma was observed in their hippocampus compared to the control group. Further analysis indicated that the EB diet decreased the caspase-3 expression in the hippocampus of rats with Aβ toxicity. Also, EB protected hippocampal pyramidal neurons against Aβ toxicity and improved the spatial distribution of the hippocampal neurons. Moreover, EB decreased the expression of inflammatory and apoptotic genes. Overall, our study suggest that EB can be considered a potent modifier of astrocytes' reactivation and inflammatory responses.
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Affiliation(s)
- Hadiseh Jahanbakhshi
- Hearing Disorders Research Center, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Meysam Hassani Moghaddam
- Department of Anatomical Sciences, Faculty of Medicine, AJA University of Medical Sciences, Tehran, Iran
| | - Mojtaba Sani
- Department of Educational Neuroscience, Aras International Campus, University of Tabriz, Tabriz, Iran
| | - Siavash Parvardeh
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mahdi Eskandarian Boroujeni
- Laboratory of Human Molecular Genetics, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, Poznan, Poland
| | - Kimia Vakili
- Student Research Committee, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mobina Fathi
- Student Research Committee, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Helia Azimi
- Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Maryam Mehranpour
- Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad-Amin Abdollahifar
- Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Shiva Ghafghazi
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Maryam Sadidi
- Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Abbas Aliaghaei
- Hearing Disorders Research Center, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Amir-Hossein Bayat
- Department of Neuroscience, School of Sciences and Advanced Technology in Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Ali Asghar Peyvandi
- Hearing Disorders Research Center, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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5
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Albini M, Krawczun-Rygmaczewska A, Cesca F. Astrocytes and brain-derived neurotrophic factor (BDNF). Neurosci Res 2023; 197:42-51. [PMID: 36780947 DOI: 10.1016/j.neures.2023.02.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 01/17/2023] [Accepted: 02/02/2023] [Indexed: 02/13/2023]
Abstract
Astrocytes are emerging in the neuroscience field as crucial modulators of brain functions, from the molecular control of synaptic plasticity to orchestrating brain-wide circuit activity for cognitive processes. The cellular pathways through which astrocytes modulate neuronal activity and plasticity are quite diverse. In this review, we focus on neurotrophic pathways, mostly those mediated by brain-derived neurotrophic factor (BDNF). Neurotrophins are a well-known family of trophic factors with pleiotropic functions in neuronal survival, maturation and activity. Within the brain, BDNF is the most abundantly expressed and most studied of all neurotrophins. While we have detailed knowledge of the effect of BDNF on neurons, much less is known about its physiology on astroglia. However, over the last years new findings emerged demonstrating that astrocytes take an active part into BDNF physiology. In this work, we discuss the state-of-the-art knowledge about astrocytes and BDNF. Indeed, astrocytes sense extracellular BDNF through its specific TrkB receptors and activate intracellular responses that greatly vary depending on the brain area, stage of development and receptors expressed. Astrocytes also uptake and recycle BDNF / proBDNF at synapses contributing to synaptic plasticity. Finally, experimental evidence is now available describing deficits in astrocytic BDNF in several neuropathologies, suggesting that astrocytic BDNF may represent a promising target for clinical translation.
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Affiliation(s)
- Martina Albini
- Department of Experimental Medicine, University of Genova, Italy; IIT Center for Synaptic Neuroscience and Technology, Genova, Italy
| | - Alicja Krawczun-Rygmaczewska
- IIT Center for Synaptic Neuroscience and Technology, Genova, Italy; Department of Life Sciences, University of Trieste, Italy
| | - Fabrizia Cesca
- IIT Center for Synaptic Neuroscience and Technology, Genova, Italy; Department of Life Sciences, University of Trieste, Italy.
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6
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Sa M, Yoo ES, Koh W, Park MG, Jang HJ, Yang YR, Bhalla M, Lee JH, Lim J, Won W, Kwon J, Kwon JH, Seong Y, Kim B, An H, Lee SE, Park KD, Suh PG, Sohn JW, Lee CJ. Hypothalamic GABRA5-positive neurons control obesity via astrocytic GABA. Nat Metab 2023; 5:1506-1525. [PMID: 37653043 DOI: 10.1038/s42255-023-00877-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 07/25/2023] [Indexed: 09/02/2023]
Abstract
The lateral hypothalamic area (LHA) regulates food intake and energy balance. Although LHA neurons innervate adipose tissues, the identity of neurons that regulate fat is undefined. Here we show that GABRA5-positive neurons in LHA (GABRA5LHA) polysynaptically project to brown and white adipose tissues in the periphery. GABRA5LHA are a distinct subpopulation of GABAergic neurons and show decreased pacemaker firing in diet-induced obesity mouse models in males. Chemogenetic inhibition of GABRA5LHA suppresses fat thermogenesis and increases weight gain, whereas gene silencing of GABRA5 in LHA decreases weight gain. In the diet-induced obesity mouse model, GABRA5LHA are tonically inhibited by nearby reactive astrocytes releasing GABA, which is synthesized by monoamine oxidase B (Maob). Gene silencing of astrocytic Maob in LHA facilitates fat thermogenesis and reduces weight gain significantly without affecting food intake, which is recapitulated by administration of a Maob inhibitor, KDS2010. We propose that firing of GABRA5LHA suppresses fat accumulation and selective inhibition of astrocytic GABA is a molecular target for treating obesity.
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Affiliation(s)
- Moonsun Sa
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seongbuk-gu, Seoul, Republic of Korea
| | - Eun-Seon Yoo
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Wuhyun Koh
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Mingu Gordon Park
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Hyun-Jun Jang
- Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Yong Ryoul Yang
- Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Mridula Bhalla
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
- IBS School, University of Science and Technology, Daejeon, Republic of Korea
| | - Jae-Hun Lee
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Jiwoon Lim
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
- IBS School, University of Science and Technology, Daejeon, Republic of Korea
| | - Woojin Won
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Jea Kwon
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Joon-Ho Kwon
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Yejin Seong
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Byungeun Kim
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology, Seoul, Republic of Korea
- Division of Bio-Medical Science and Technology, University of Science and Technology, Daejeon, Republic of Korea
| | - Heeyoung An
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Seung Eun Lee
- Virus Facility, Research Animal Resource Center, Korea Institute of Science and Technology, Seoul, Republic of Korea
| | - Ki Duk Park
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology, Seoul, Republic of Korea
- Division of Bio-Medical Science and Technology, University of Science and Technology, Daejeon, Republic of Korea
| | - Pann-Ghill Suh
- Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Jong-Woo Sohn
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - C Justin Lee
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea.
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seongbuk-gu, Seoul, Republic of Korea.
- IBS School, University of Science and Technology, Daejeon, Republic of Korea.
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7
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Drew VJ, Park M, Kim T. GABA-Positive Astrogliosis in Sleep-Promoting Areas Associated with Sleep Disturbance in 5XFAD Mice. Int J Mol Sci 2023; 24:9695. [PMID: 37298646 PMCID: PMC10253883 DOI: 10.3390/ijms24119695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 05/29/2023] [Accepted: 05/31/2023] [Indexed: 06/12/2023] Open
Abstract
Sleep disturbances, a debilitating symptom of Alzheimer's disease (AD), are associated with neuropathological changes. However, the relationship between these disturbances and regional neuron and astrocyte pathologies remains unclear. This study examined whether sleep disturbances in AD result from pathological changes in sleep-promoting brain areas. Male 5XFAD mice underwent electroencephalography (EEG) recordings at 3, 6, and 10 months, followed by an immunohistochemical analysis of three brain regions associated with sleep promotion. The findings showed that 5XFAD mice demonstrated reduced duration and bout counts of nonrapid eye movement (NREM) sleep by 6 months and reduced duration and bout counts of rapid eye movement (REM) sleep by 10 months. Additionally, peak theta EEG power frequency during REM sleep decreased by 10 months. Sleep disturbances correlated with the total number of GFAP-positive astrocytes and the ratio of GFAP- and GABA-positive astrocytes across all three sleep-associated regions corresponding to their roles in sleep promotion. The presence of GABRD in sleep-promoting neurons indicated their susceptibility to inhibition by extrasynaptic GABA. This study reveals that neurotoxic reactive astrogliosis in NREM and REM sleep-promoting areas is linked to sleep disturbances in 5XFAD mice, which suggests a potential target for the treatment of sleep disorders in AD.
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Affiliation(s)
| | | | - Tae Kim
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea; (V.J.D.); (M.P.)
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8
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Valles SL, Singh SK, Campos-Campos J, Colmena C, Campo-Palacio I, Alvarez-Gamez K, Caballero O, Jorda A. Functions of Astrocytes under Normal Conditions and after a Brain Disease. Int J Mol Sci 2023; 24:ijms24098434. [PMID: 37176144 PMCID: PMC10179527 DOI: 10.3390/ijms24098434] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 04/26/2023] [Accepted: 05/05/2023] [Indexed: 05/15/2023] Open
Abstract
In the central nervous system (CNS) there are a greater number of glial cells than neurons (between five and ten times more). Furthermore, they have a greater number of functions (more than eight functions). Glia comprises different types of cells, those of neural origin (astrocytes, radial glia, and oligodendroglia) and differentiated blood monocytes (microglia). During ontogeny, neurons develop earlier (at fetal day 15 in the rat) and astrocytes develop later (at fetal day 21 in the rat), which could indicate their important and crucial role in the CNS. Analysis of the phylogeny reveals that reptiles have a lower number of astrocytes compared to neurons and in humans this is reversed, as there have a greater number of astrocytes compared to neurons. These data perhaps imply that astrocytes are important and special cells, involved in many vital functions, including memory, and learning processes. In addition, astrocytes are involved in different mechanisms that protect the CNS through the production of antioxidant and anti-inflammatory proteins and they clean the extracellular environment and help neurons to communicate correctly with each other. The production of inflammatory mediators is important to prevent changes in brain homeostasis. On the contrary, excessive, or continued production appears as a characteristic element in many diseases, such as Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), and in neurodevelopmental diseases, such as bipolar disorder, schizophrenia, and autism. Furthermore, different drugs and techniques have been developed to reverse oxidative stress and/or excess of inflammation that occurs in many CNS diseases, but much remains to be investigated. This review attempts to highlight the functional relevance of astrocytes in normal and neuropathological conditions by showing the molecular and cellular mechanisms of their role in the CNS.
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Affiliation(s)
- Soraya L Valles
- Department of Physiology, School of Medicine, University of Valencia, Blasco Ibañez 15, 46010 Valencia, Spain
| | - Sandeep Kumar Singh
- Indian Scientific Education and Technology Foundation, Lucknow 226002, India
| | - Juan Campos-Campos
- Department of Physiology, School of Medicine, University of Valencia, Blasco Ibañez 15, 46010 Valencia, Spain
- Faculty of Nursing and Podiatry, University of Valencia, 46010 Valencia, Spain
| | - Carlos Colmena
- Department of Physiology, School of Medicine, University of Valencia, Blasco Ibañez 15, 46010 Valencia, Spain
| | - Ignacio Campo-Palacio
- Department of Physiology, School of Medicine, University of Valencia, Blasco Ibañez 15, 46010 Valencia, Spain
| | - Kenia Alvarez-Gamez
- Department of Physiology, School of Medicine, University of Valencia, Blasco Ibañez 15, 46010 Valencia, Spain
| | - Oscar Caballero
- Department of Physiology, School of Medicine, University of Valencia, Blasco Ibañez 15, 46010 Valencia, Spain
- Faculty of Nursing and Podiatry, University of Valencia, 46010 Valencia, Spain
| | - Adrian Jorda
- Department of Physiology, School of Medicine, University of Valencia, Blasco Ibañez 15, 46010 Valencia, Spain
- Faculty of Nursing and Podiatry, University of Valencia, 46010 Valencia, Spain
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9
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Cunha Feio Leal MD, Amaral Junior FLD, Silva Arruda BFD, Kurosawa JAA, Vieira AA, Maia JCC, Scalfoni VVB, Silveira Junior AMD, Feijó MO, Albuquerque FBAD, Marta MHM, Normando MPN, Silva AGOCD, Trindade FCPD, Siqueira Mendes FDCCD, Sosthenes MCK. The Masticatory Activity Interference in Quantitative Estimation of CA1, CA3 and Dentate Gyrus Hippocampal Astrocytes of Aged Murine Models and under Environmental Stimulation. Int J Mol Sci 2023; 24:ijms24076529. [PMID: 37047502 PMCID: PMC10095286 DOI: 10.3390/ijms24076529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/22/2023] [Accepted: 03/01/2023] [Indexed: 04/03/2023] Open
Abstract
Studies indicating the influence of masticatory dysfunction, due to a soft diet or lack of molars, on impairing spatial memory and learning have led to research about neuronal connections between areas and cell populations possibly affected. In this sense, with scarce detailed data on the subfields of hippocampus in dementia neurodegeneration, there is no information about astrocytic responses in its different layers. Thus, considering this context, the present study evaluated the effects of deprivation and rehabilitation of masticatory activity, aging, and environmental enrichment on the stereological quantification of hippocampal astrocytes from layers CA1, CA3, and DG. For this purpose, we examined mature (6-month-old; 6M), and aged (18-month-old; 18M) mice, subjected to distinct masticatory regimens and environments. Three different regimens of masticatory activity were applied: continuous normal mastication with hard pellets (HD); normal mastication followed by deprived mastication with equal periods of pellets followed by soft powder (HD/SD); or rehabilitated masticatory activity with equal periods of HD, followed by powder, followed by pellets (HD/SD/HD). Under each specific regimen, half of the animals were raised in standard cages (impoverished environment (IE)) and the other half in enriched cages (enriched environment (EE)), mimicking sedentary or active lifestyles. Microscopic stereological, systematic, and random sampling approaches with an optical dissector of GFAP-immunolabeled astrocytes were done, allowing for an astrocyte numerical estimate. Stratum moleculare and hilus, from the dentate gyrus (DG) and Strata Lacunosum-Moleculare, Oriens, and Radiatum, similarly to the dentate gyrus, showed no significant change in any of the investigated variables (age, diet, or environment) in these layers. However, in Stratum radiatum, it was possible to observe significant differences associated with diet regimens and age. Therefore, diet-related differences were found when the HD 18M IE group was compared to the HD/SD/HD 18-month-old group in the same environment (IE) (p = 0.007). In the present study, we present modulatory factors (masticatory function, environmental enrichment, and aging) for the differentiated quantitative laminar response in the hippocampal regions, suggesting other studies to read the plasticity and responsiveness of astrocytes, including the molecular background.
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Affiliation(s)
- Marília da Cunha Feio Leal
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil
| | - Fabio Leite do Amaral Junior
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil
| | - Bernardo Freire da Silva Arruda
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil
| | | | - Amanda Almeida Vieira
- Curso de Medicina, Centro Universitário do Estado do Pará, Belém 66613-903, PA, Brazil
| | | | | | - Antonio Morais da Silveira Junior
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil
| | - Matheus Oliveira Feijó
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil
| | - Fernanda Beatriz Araújo de Albuquerque
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil
| | | | | | - Alana Gabriele Oliveira Cabeça da Silva
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil
| | - Fernanda Catharina Pires da Trindade
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil
| | - Fabíola de Carvalho Chaves de Siqueira Mendes
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil
- Curso de Medicina, Centro Universitário do Estado do Pará, Belém 66613-903, PA, Brazil
| | - Marcia Consentino Kronka Sosthenes
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil
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10
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Murray TE, Richards CM, Robert-Gostlin VN, Bernath AK, Lindhout IA, Klegeris A. Potential neurotoxic activity of diverse molecules released by astrocytes. Brain Res Bull 2022; 189:80-101. [PMID: 35988785 DOI: 10.1016/j.brainresbull.2022.08.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 07/04/2022] [Accepted: 08/14/2022] [Indexed: 11/02/2022]
Abstract
Astrocytes are the main support cells of the central nervous system. They also participate in neuroimmune reactions. In response to pathological and immune stimuli, astrocytes transform to reactive states characterized by increased release of inflammatory mediators. Some of these molecules are neuroprotective and inflammation resolving while others, including reactive oxygen species (ROS), nitric oxide (NO), matrix metalloproteinase (MMP)- 9, L-glutamate, and tumor necrosis factor α (TNF), are well-established toxins known to cause damage to surrounding cells and tissues. We hypothesized that similar to microglia, the brain immune cells, reactive astrocytes can release a broader set of diverse molecules that are potentially neurotoxic. A literature search was conducted to identify such molecules using the following two criteria: 1) evidence of their expression and secretion by astrocytes and 2) direct neurotoxic action. This review describes 14 structurally diverse molecules as less-established astrocyte neurotoxins, including C-X-C motif chemokine ligand (CXCL)10, CXCL12/CXCL12(5-67), FS-7-associated surface antigen ligand (FasL), macrophage inflammatory protein (MIP)- 2α, TNF-related apoptosis inducing ligand (TRAIL), pro-nerve growth factor (proNGF), pro-brain-derived neurotrophic factor (proBDNF), chondroitin sulfate proteoglycans (CSPGs), cathepsin (Cat)B, group IIA secretory phospholipase A2 (sPLA2-IIA), amyloid beta peptides (Aβ), high mobility group box (HMGB)1, ceramides, and lipocalin (LCN)2. For some of these molecules, further studies are required to establish either their direct neurotoxic effects or the full spectrum of stimuli that induce their release by astrocytes. Only limited studies with human-derived astrocytes and neurons are available for most of these potential neurotoxins, which is a knowledge gap that should be addressed in the future. We also summarize available evidence of the role these molecules play in select neuropathologies where reactive astrocytes are a key feature. A comprehensive understanding of the full spectrum of neurotoxins released by reactive astrocytes is key to understanding neuroinflammatory diseases characterized by the adverse activation of these cells and may guide the development of novel treatment strategies.
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Affiliation(s)
- Taryn E Murray
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia V1V 1V7, Canada
| | - Christy M Richards
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia V1V 1V7, Canada
| | - Victoria N Robert-Gostlin
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia V1V 1V7, Canada
| | - Anna K Bernath
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia V1V 1V7, Canada
| | - Ivan A Lindhout
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia V1V 1V7, Canada
| | - Andis Klegeris
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia V1V 1V7, Canada.
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11
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Sa M, Lee JM, Park MG, Lim J, Kim JMJ, Koh W, Yoon BE, Lee CJ. Unaltered Tonic Inhibition in the Arcuate Nucleus of Diet-induced Obese Mice. Exp Neurobiol 2022; 31:147-157. [PMID: 35786638 PMCID: PMC9272119 DOI: 10.5607/en22014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 05/17/2022] [Accepted: 05/18/2022] [Indexed: 11/19/2022] Open
Abstract
The principal inhibitory transmitter, γ-aminobutyric acid (GABA), is critical for maintaining hypothalamic homeostasis and released from neurons phasically, as well as from astrocytes tonically. Although astrocytes in the arcuate nucleus (ARC) of the hypothalamus are shown to transform into reactive astrocytes, the tonic inhibition by astrocytic GABA has not been adequately investigated in diet-induced obesity (DIO). Here, we investigated the expression of monoamine oxidase-B (MAOB), a GABA-synthesizing enzyme, in reactive astrocytes in obese mice. We observed that a chronic high-fat diet (HFD) significantly increased astrocytic MAOB and cellular GABA content, along with enhanced hypertrophy of astrocytes in the ARC. Unexpectedly, we found that the level of tonic GABA was unaltered in chronic HFD mice using whole-cell patch-clamp recordings in the ARC. Furthermore, the GABA-induced current was increased with elevated GABAA receptor α5 (GABRA5) expression. Surprisingly, we found that a nonselective GABA transporter (GAT) inhibitor, nipecotic acid (NPA)-induced current was significantly increased in chronic HFD mice. We observed that GAT1 inhibitor, NO711-induced current was significantly increased, whereas GAT3 inhibitor, SNAP5114-induced current was not altered. The unexpected unaltered tonic inhibition was due to an increase of GABA clearance in the ARC by neuronal GAT1 rather than astrocytic GAT3. These results imply that increased astrocytic GABA synthesis and neuronal GABAA receptor were compensated by GABA clearance, resulting in unaltered tonic GABA inhibition in the ARC of the hypothalamus in obese mice. Taken together, GABA-related molecular pathways in the ARC dynamically regulate the tonic inhibition to maintain hypothalamic homeostasis against the HFD challenge.
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Affiliation(s)
- Moonsun Sa
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon 34126, Korea
| | - Jung Moo Lee
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon 34126, Korea
| | - Mingu Gordon Park
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon 34126, Korea
| | - Jiwoon Lim
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon 34126, Korea
- IBS School, University of Science and Technology (UST), Daejeon 34126, Korea
| | | | - Wuhyun Koh
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon 34126, Korea
| | - Bo-Eun Yoon
- Department of Molecular Biology, Dankook University, Cheonan 31116, Korea
| | - C. Justin Lee
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon 34126, Korea
- IBS School, University of Science and Technology (UST), Daejeon 34126, Korea
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12
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Chun H, Lim J, Park KD, Lee CJ. Inhibition of monoamine oxidase B prevents reactive astrogliosis and scar formation in stab wound injury model. Glia 2021; 70:354-367. [PMID: 34713936 DOI: 10.1002/glia.24110] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 10/13/2021] [Accepted: 10/19/2021] [Indexed: 11/07/2022]
Abstract
Reactive astrocytes manifest molecular, structural, and functional alterations under various pathological conditions. We have previously demonstrated that the reactive astrocytes of the stab wound injury model (STAB) display aberrant cellular gamma-aminobutyric acid (GABA) content and tonic GABA release, whereas the active astrocytes under enriched environment (EE) express high levels of proBDNF. However, the role of monoamine oxidase B (MAO-B) in reactive astrogliosis and hypertrophy still remains unknown. Here, we investigate the role of MAO-B, a GABA-producing enzyme, in reactive astrogliosis in STAB. We observed that the genetic removal of MAO-B significantly reduced the hypertrophy, scar formation, and GABA production of reactive astrocytes, whereas the MAO-B overexpression under glial fibrillary acidic protein (GFAP) promoter enhanced the levels of GFAP and GABA. Furthermore, we found that one of the by-products of the MAO-B action, H2 O2 , but not GABA, was sufficient and necessary for the hypertrophy of reactive astrocytes. Notably, we identified two potent pharmacological tools to attenuate scar-forming astrogliosis-the recently developed reversible MAO-B inhibitor, KDS2010, and an H2 O2 scavenger, crisdesalazine (AAD-2004). Our results implicate that inhibiting MAO-B activity has dual beneficial effects in preventing astrogliosis and scar-formation under brain injury, and that the MAO-B/H2 O2 pathway can be a useful therapeutic target with a high clinical potential.
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Affiliation(s)
- Heejung Chun
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, Republic of Korea
| | - Jiwoon Lim
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, Republic of Korea.,IBS School, University of Science and Technology (UST), Daejeon, Republic of Korea
| | - Ki Duk Park
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Korea Institute of Science and Technology, Seoul, Republic of Korea.,Division of Bio-Med Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul, Republic of Korea
| | - C Justin Lee
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, Republic of Korea.,IBS School, University of Science and Technology (UST), Daejeon, Republic of Korea
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13
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Cho HU, Kim S, Sim J, Yang S, An H, Nam MH, Jang DP, Lee CJ. Redefining differential roles of MAO-A in dopamine degradation and MAO-B in tonic GABA synthesis. Exp Mol Med 2021; 53:1148-1158. [PMID: 34244591 PMCID: PMC8333267 DOI: 10.1038/s12276-021-00646-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 05/07/2021] [Accepted: 05/11/2021] [Indexed: 12/21/2022] Open
Abstract
Monoamine oxidase (MAO) is believed to mediate the degradation of monoamine neurotransmitters, including dopamine, in the brain. Between the two types of MAO, MAO-B has been believed to be involved in dopamine degradation, which supports the idea that the therapeutic efficacy of MAO-B inhibitors in Parkinson's disease can be attributed to an increase in extracellular dopamine concentration. However, this belief has been controversial. Here, by utilizing in vivo phasic and basal electrochemical monitoring of extracellular dopamine with fast-scan cyclic voltammetry and multiple-cyclic square wave voltammetry and ex vivo fluorescence imaging of dopamine with GRABDA2m, we demonstrate that MAO-A, but not MAO-B, mainly contributes to striatal dopamine degradation. In contrast, our whole-cell patch-clamp results demonstrated that MAO-B, but not MAO-A, was responsible for astrocytic GABA-mediated tonic inhibitory currents in the rat striatum. We conclude that, in contrast to the traditional belief, MAO-A and MAO-B have profoundly different roles: MAO-A regulates dopamine levels, whereas MAO-B controls tonic GABA levels.
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Affiliation(s)
- Hyun-U Cho
- Department of Biomedical Engineering, Hanyang University, Seoul, Korea
| | - Sunpil Kim
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, Korea
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Korea
| | - Jeongeun Sim
- Department of Biomedical Engineering, Hanyang University, Seoul, Korea
| | - Seulkee Yang
- Center for Neuroscience, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Korea
| | - Heeyoung An
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, Korea
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Korea
| | - Min-Ho Nam
- Center for Neuroscience, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Korea.
- Department of KHU-KIST Convergence Science and Technology, Kyung Hee University, Seoul, Korea.
| | - Dong-Pyo Jang
- Department of Biomedical Engineering, Hanyang University, Seoul, Korea.
| | - C Justin Lee
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, Korea.
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Korea.
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14
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An H, Lee H, Yang S, Won W, Lee CJ, Nam MH. Adenovirus-induced Reactive Astrogliosis Exacerbates the Pathology of Parkinson's Disease. Exp Neurobiol 2021; 30:222-231. [PMID: 34045369 PMCID: PMC8278136 DOI: 10.5607/en21013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 05/23/2021] [Accepted: 05/23/2021] [Indexed: 12/17/2022] Open
Abstract
Parkinson's disease (PD) is the most prevalent neurodegenerative motor disorder. While PD has been attributed to dopaminergic neuronal death in substantia nigra pars compacta (SNpc), accumulating lines of evidence have suggested that reactive astrogliosis is critically involved in PD pathology. These pathological changes are associated with α-synuclein aggregation, which is more prone to be induced by an A53T mutation. Therefore, the overexpression of A53T-mutated α-synuclein (A53T-α-syn) has been utilized as a popular animal model of PD. However, this animal model only shows marginal-to-moderate extents of reactive astrogliosis and astrocytic α-synuclein accumulation, while these phenomena are prominent in human PD brains. Here we show that Adeno-GFAP-GFP virus injection into SNpc causes severe reactive astrogliosis and exacerbates the A53T-α-syn-mediated PD pathology. In particular, we demonstrate that AAV-CMV-A53T-α-syn injection, when combined with Adeno-GFAP-GFP, causes more significant loss of dopaminergic neuronal tyrosine hydroxylase level and gain of astrocytic GFAP and GABA levels. Moreover, the combination of AAV-CMV-A53T-α-syn and Adeno-GFAP-GFP causes an extensive astrocytic α-syn expression, just as in human PD brains. These results are in marked contrast to previous reports that AAV-CMV-A53T-α-syn alone causes α-syn expression mostly in neurons but rarely in astrocytes. Furthermore, the combination causes a severe PD-like motor dysfunction as assessed by rotarod and cylinder tests within three weeks from the virus injection, whereas Adeno-GFAP-GFP alone or AAV-CMV-A53T-α-syn alone does not. Our findings implicate that inducing reactive astrogliosis exacerbates PD-like pathologies and propose the virus combination as an advanced strategy for developing a new animal model of PD.
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Affiliation(s)
- Heeyoung An
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Korea
| | - Hyowon Lee
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea
- Department of Korean Medical Science, Graduate School, Kyung Hee University, Seoul 02447, Korea
| | - Seulkee Yang
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea
- Division of Bio-Medical Science & Technology, KIST School, University of Science and Technology, Seoul 02792, Korea
| | - Woojin Won
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Korea
| | - C. Justin Lee
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Korea
| | - Min-Ho Nam
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea
- Department of KHU-KIST Convergent Science and Technology, Kyung Hee University, Seoul 02447, Korea
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15
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Excessive Astrocytic GABA Causes Cortical Hypometabolism and Impedes Functional Recovery after Subcortical Stroke. Cell Rep 2021; 32:107861. [PMID: 32640227 DOI: 10.1016/j.celrep.2020.107861] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 05/18/2020] [Accepted: 06/12/2020] [Indexed: 11/20/2022] Open
Abstract
Glucose hypometabolism in cortical structures after functional disconnection is frequently reported in patients with white matter diseases such as subcortical stroke. However, the molecular and cellular mechanisms have been poorly elucidated. Here we show, in an animal model of internal capsular infarct, that GABA-synthesizing reactive astrocytes in distant cortical areas cause glucose hypometabolism via tonic inhibition of neighboring neurons. We find that reversal of aberrant astrocytic GABA synthesis, by pharmacological inhibition and astrocyte-specific gene silencing of MAO-B, reverses the reduction in cortical glucose metabolism. Moreover, induction of aberrant astrocytic GABA synthesis by cortical injection of putrescine or adenovirus recapitulates cortical hypometabolism. Furthermore, MAO-B inhibition causes a remarkable recovery from post-stroke motor deficits when combined with a rehabilitation regimen. Collectively, our data indicate that cortical glucose hypometabolism in subcortical stroke is caused by aberrant astrocytic GABA and MAO-B inhibition and that attenuating cortical hypometabolism can be a therapeutic approach in subcortical stroke.
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16
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Andika FR, Yoon JH, Kim GS, Jeong Y. Intermittent Fasting Alleviates Cognitive Impairments and Hippocampal Neuronal Loss but Enhances Astrocytosis in Mice with Subcortical Vascular Dementia. J Nutr 2021; 151:722-730. [PMID: 33484139 DOI: 10.1093/jn/nxaa384] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/22/2020] [Accepted: 11/10/2020] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Intermittent fasting (IF) is found to exhibit neuroprotection against various insults, including ischemia; however, IF has been mainly applied before disease onset. It remains unknown whether IF implementation alleviates the long-term detrimental effects of a disease after its establishment. OBJECTIVES To investigate the IF effects on cognitive impairments and cerebrovascular pathologies in a subcortical vascular dementia (SVaD) mouse model. METHODS The SVaD model was developed by inducing hypoperfusion and hyperlipidemia in apoE-deficient (apoE-/-) mice. We subjected 10-week-old apoE-/- mice to bilateral common carotid artery stenosis using micro-coils after they were fed a high-fat diet (HFD; 45% energy) for 6 weeks to induce hyperlipidemia. Age-matched wild-type C57BL/6J mice received sham surgery after undergoing an identical HFD treatment. Both the SVaD model and wild-type mice either started a 1-month IF regimen (time-restricted feeding for 6 hours per day) or continued the standard diet ad libitum (6.2% fat energy) at 8 weeks post-surgery. We assessed mice weight, food intake, and outcomes in a behavioral test battery before, during, and after the IF regimen, prior to histopathological analyses (microvessel density, neuronal density, white matter damage, astrocytosis) of their brains. RESULTS SVaD model mice on the IF regimen (SVaD-IF) exhibited higher mean recognition and spatial working memory performance compared to SVaD mice fed ad libitum (SVaD-AL; P < 0.01). Additionally, SVaD-IF mice had ∼5% higher hippocampal neuronal density in the dentate gyrus (DG) and cornu ammonis 1 regions than SVaD-AL mice (P < 0.001), which paralleled their post-IF cognitive enhancements. However, SVaD-IF mice showed an ∼50% increase in hippocampal DG astrocytosis compared to SVaD-AL mice (P < 0.05), with no significant differences in microvessel densities among the 2 groups. CONCLUSIONS The improvements in SVaD-IF mice suggest that IF could be a potential nonpharmacological remedy for SVaD. This finding could stimulate future investigations on IF's neuroprotective potential across many neurovascular diseases.
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Affiliation(s)
- Faris Rizky Andika
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.,KAIST Institute for Health Science and Technology, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Jin-Hui Yoon
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.,KAIST Institute for Health Science and Technology, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Gaon Sandy Kim
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.,KAIST Institute for Health Science and Technology, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Yong Jeong
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.,KAIST Institute for Health Science and Technology, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
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17
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Fernandez-Abascal J, Graziano B, Encalada N, Bianchi L. Glial Chloride Channels in the Function of the Nervous System Across Species. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1349:195-223. [PMID: 35138616 PMCID: PMC11247392 DOI: 10.1007/978-981-16-4254-8_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
In the nervous system, the concentration of Cl- in neurons that express GABA receptors plays a key role in establishing whether these neurons are excitatory, mostly during early development, or inhibitory. Thus, much attention has been dedicated to understanding how neurons regulate their intracellular Cl- concentration. However, regulation of the extracellular Cl- concentration by other cells of the nervous system, including glia and microglia, is as important because it ultimately affects the Cl- equilibrium potential across the neuronal plasma membrane. Moreover, Cl- ions are transported in and out of the cell, via either passive or active transporter systems, as counter ions for K+ whose concentration in the extracellular environment of the nervous system is tightly regulated because it directly affects neuronal excitability. In this book chapter, we report on the Cl- channel types expressed in the various types of glial cells focusing on the role they play in the function of the nervous system in health and disease. Furthermore, we describe the types of stimuli that these channels are activated by, the other solutes that they may transport, and the involvement of these channels in processes such as pH regulation and Regulatory Volume Decrease (RVD). The picture that emerges is one of the glial cells expressing a variety of Cl- channels, encoded by members of different gene families, involved both in short- and long-term regulation of the nervous system function. Finally, we report data on invertebrate model organisms, such as C. elegans and Drosophila, that are revealing important and previously unsuspected functions of some of these channels in the context of living and behaving animals.
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Affiliation(s)
- Jesus Fernandez-Abascal
- Department Physiology and Biophysics, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Bianca Graziano
- Department Physiology and Biophysics, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Nicole Encalada
- Department Physiology and Biophysics, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Laura Bianchi
- Department Physiology and Biophysics, University of Miami, Miller School of Medicine, Miami, FL, USA.
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18
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Severe reactive astrocytes precipitate pathological hallmarks of Alzheimer's disease via H 2O 2- production. Nat Neurosci 2020; 23:1555-1566. [PMID: 33199896 DOI: 10.1038/s41593-020-00735-y] [Citation(s) in RCA: 152] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 10/07/2020] [Indexed: 12/29/2022]
Abstract
Although the pathological contributions of reactive astrocytes have been implicated in Alzheimer's disease (AD), their in vivo functions remain elusive due to the lack of appropriate experimental models and precise molecular mechanisms. Here, we show the importance of astrocytic reactivity on the pathogenesis of AD using GiD, a newly developed animal model of reactive astrocytes, where the reactivity of astrocytes can be manipulated as mild (GiDm) or severe (GiDs). Mechanistically, excessive hydrogen peroxide (H2O2) originated from monoamine oxidase B in severe reactive astrocytes causes glial activation, tauopathy, neuronal death, brain atrophy, cognitive impairment and eventual death, which are significantly prevented by AAD-2004, a potent H2O2 scavenger. These H2O2--induced pathological features of AD in GiDs are consistently recapitulated in a three-dimensional culture AD model, virus-infected APP/PS1 mice and the brains of patients with AD. Our study identifies H2O2 from severe but not mild reactive astrocytes as a key determinant of neurodegeneration in AD.
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19
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Choi M, Kim H, Yang EJ, Kim HS. Inhibition of STAT3 phosphorylation attenuates impairments in learning and memory in 5XFAD mice, an animal model of Alzheimer's disease. J Pharmacol Sci 2020; 143:290-299. [PMID: 32507685 DOI: 10.1016/j.jphs.2020.05.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 05/01/2020] [Accepted: 05/18/2020] [Indexed: 02/07/2023] Open
Abstract
The pathophysiological roles of astrocytes in the reactive state are thought to have important significance in the pathogenesis of neurodegenerative diseases, including Alzheimer's disease (AD). However, the detailed mechanisms underlying the transition of astrocytes from the resting state to the reactive state during neurodegenerative disease largely remain to be defined. Here, we investigated the pathways involved in activating astrocytes from the resting state to the reactive state in primary cultured astrocytes treated with oligomeric Aβ and in the hippocampus of 5XFAD mice. Treatment with oligomeric Aβ induced an increase in reactive astrocytes, as assessed by the protein level of glial fibrillary acidic protein (GFAP) and this increase was caused by STAT3 phosphorylation in primary cultured astrocytes. The administration of Stattic, an inhibitor of STAT3, rescued the activation of astrocytes in primary cultured astrocytes and in the hippocampus of 6-month-old 5XFAD mice as well as impairments in learning and memory. Collectively, these results demonstrated that reactive astrocytes in the AD brain are induced via STAT3 and the impairments in learning and memory observed in 5XFAD mice are rescued by STAT3 inhibition, suggesting that the inhibition of STAT3 phosphorylation in astrocytes may be a novel therapeutic target for cognitive impairment in AD.
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Affiliation(s)
- Moonseok Choi
- Department of Pharmacology and Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Hyunju Kim
- Department of Pharmacology and Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Eun-Jeong Yang
- Department of Pharmacology and Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Hye-Sun Kim
- Department of Pharmacology and Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea; Seoul National University Bundang Hospital, Seoul National University College of Medicine, Sungnam, Republic of Korea; Dementia Research Center, Seoul National University College of Medicine, Seoul, Republic of Korea.
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20
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Mohammadi M, Manaheji H, Maghsoudi N, Danyali S, Baniasadi M, Zaringhalam J. Microglia dependent BDNF and proBDNF can impair spatial memory performance during persistent inflammatory pain. Behav Brain Res 2020; 390:112683. [PMID: 32442548 DOI: 10.1016/j.bbr.2020.112683] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Revised: 03/15/2020] [Accepted: 04/27/2020] [Indexed: 12/30/2022]
Abstract
Inflammatory pain is commonly associated with cognitive impairment. However, its molecular mechanisms are poorly understood. Thus, this study was conducted to investigate the molecular mechanisms of behavioral changes associated with inflammatory pain. Briefly, 36 Wistar rats were randomly divided into two main groups: CFA group treated with 100 μL of Complete Freunds' Adjuvant (CFA) and CFA + Minocycline group treated with 100 μL of CFA+40 mg/kg/day of minocycline). After that, each group was divided into three subgroups based on different time points of the study. The pain was induced using CFA and subsequent behavioral changes (i.e., hyperalgesia and learning and spatial memory) were analyzed by the Morris Water Maze (MWM) task and Radiant Heat. Then, the cellular and molecular changes were assessed using Western Blotting, Immunohistochemistry, and Terminal deoxynucleotidyl transferase dUTP Nick End Labeling (TUNEL) techniques. Results of the study indicated that CFA-induced pain impaired spatial learning and memory functions. Studying the cellular changes showed that persistent inflammatory pain increased the microglial activity in CA1 and Dentate Gyrus (DG) regions. Furthermore, an increase was observed in the percentage of TUNEL-positive cells. Also, pro-Brain-Derived Neurotrophic Factor (BDNF)/BDNF ratio, Caspase3, and Receptor-Interacting Protein kinase 3 (RIP3) levels increased in the rats' hippocampus following induction of persistent inflammatory pain. These changes were reversed following the cessation of pain as well as the injection of minocycline. Taking together, the results of the current study for the first time revealed that an increase in the microglia dependent proBDNF/BDNF ratio following persistent inflammatory pain leads to cell death of the CA1 and DG neurons that subsequently causes a cognitive deficit in the learning and spatial memory functions.
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Affiliation(s)
- Mola Mohammadi
- Physiology Department, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neurophysiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Homa Manaheji
- Physiology Department, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neurophysiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Nader Maghsoudi
- Department of Biology, Queens College and Graduate Center of the City University of New York, Flushing, NY, USA; Neurobiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Samira Danyali
- Physiology Department, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neurophysiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mansoureh Baniasadi
- Physiology Department, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neurophysiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Jalal Zaringhalam
- Physiology Department, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neurophysiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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21
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Kim HS, Jeon I, Noh JE, Lee H, Hong KS, Lee N, Pei Z, Song J. Intracerebral Transplantation of BDNF-overexpressing Human Neural Stem Cells (HB1.F3.BDNF) Promotes Migration, Differentiation and Functional Recovery in a Rodent Model of Huntington's Disease. Exp Neurobiol 2020; 29:130-137. [PMID: 32408403 PMCID: PMC7237270 DOI: 10.5607/en20011] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 04/13/2020] [Accepted: 04/13/2020] [Indexed: 02/06/2023] Open
Abstract
Huntington's disease (HD) is a dominantly inherited neurodegenerative disorder caused by abnormally expanded CAG repeats in the huntingtin gene. The huntingtin gene mutation leads to the progressive degeneration of striatal GABAergic medium spiny neurons (MSN) and reduces the level of brain-derived neurotrophic factor (BDNF) in HD patient's brain. BDNF is an essential neurotrophic factor for the cortico-striatal synaptic activity and the survival of GABAergic neurons. In this study, we transplanted BDNF-overexpressing human neural stem cells (HB1.F3.BDNF) into the contra-lateral side of unilateral quinolinic acid (QA)-lesioned striatum of HD rat model. The results of in vivo transplantation were monitored using various behavioral tests, 4.7 T animal magnetic resonance imaging (MRI) and immunohistochemical staining. We observed that the QA-lesioned rats receiving HB1.F3.BDNF cells exhibited significant behavioral improvements in the stepping, rotarod and apomorphine-induced rotation tests. Interestingly, contralaterally transplanted cells were migrated to the QA-lesioned striatum and the size of lateral ventricle was reduced. Histological analyses further revealed that the transplanted cells, which had migrated to the QA lesion site, were differentiated into the cells of GABAergic, MSN-type neurons expressing DARPP-32, and neural networks were established between the transplanted cells and the host brain, as revealed by retrograde tracing. Finally, there was a significant reduction of inflammatory response in HB1.F3.BDNF-transplanted HD animal model, compared with vehicle-transplanted group. Taken together, these results suggest that HB1.F3.BDNF can be an effective therapeutic strategy to treat HD patients in the future.
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Affiliation(s)
- Hyun Sook Kim
- Department of Neurology, CHA Bundang Medical Center, CHA University, Seongnam 3496, Korea
| | - Iksoo Jeon
- CHA Stem Cell Institute, Department of Biomedical Science, CHA University, Seongnam 13488, Korea
| | - Jeong-Eun Noh
- CHA Stem Cell Institute, Department of Biomedical Science, CHA University, Seongnam 13488, Korea
| | - Hyunseung Lee
- Division of Magnetic Imaging Resonance, Korea Basic Science Institute, Cheongju 28119, Korea
| | - Kwan Soo Hong
- Division of Magnetic Imaging Resonance, Korea Basic Science Institute, Cheongju 28119, Korea
| | - Nayeon Lee
- CHA Stem Cell Institute, Department of Biomedical Science, CHA University, Seongnam 13488, Korea
| | - Zhong Pei
- Department of Neurology, National Key Clinical Department and Key Discipline of Neurology, The First Affi liated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Jihwan Song
- CHA Stem Cell Institute, Department of Biomedical Science, CHA University, Seongnam 13488, Korea
- iPS Bio, Inc., Seongnam 1322, Korea
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22
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Khodaei S, Avramescu S, Wang DS, Sheng H, Chan NK, Lecker I, Fernandez-Escobar A, Lei G, Dewar MB, Whissell PD, Baker AJ, Orser BA. Inhibiting α5 Subunit-Containing γ-Aminobutyric Acid Type A Receptors Attenuates Cognitive Deficits After Traumatic Brain Injury. Crit Care Med 2020; 48:533-544. [PMID: 32205600 DOI: 10.1097/ccm.0000000000004161] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
OBJECTIVES Cognitive deficits after traumatic brain injury are a leading cause of disability worldwide, yet no effective pharmacologic treatments exist to improve cognition. Traumatic brain injury increases proinflammatory cytokines, which trigger excess function of α5 subunit-containing γ-aminobutyric acid type A receptors. In several models of brain injury, drugs that inhibit α5 subunit-containing γ-aminobutyric acid type A receptor function improve cognitive performance. Thus, we postulated that inhibiting α5 subunit-containing γ-aminobutyric acid type A receptors would improve cognitive performance after traumatic brain injury. In addition, because traumatic brain injury reduces long-term potentiation in the hippocampus, a cellular correlate of memory, we studied whether inhibition of α5 subunit-containing γ-aminobutyric acid type A receptors attenuated deficits in long-term potentiation after traumatic brain injury. DESIGN Experimental animal study. SETTING Research laboratory. SUBJECTS Adult male mice and hippocampal brain slices. INTERVENTIONS Anesthetized mice were subjected to traumatic brain injury with a closed-head, free-weight drop method. One week later, the mice were treated with L-655,708 (0.5 mg/kg), an inhibitor that is selective for α5 subunit-containing γ-aminobutyric acid type A receptors, 30 minutes before undergoing behavioral testing. Problem-solving abilities were assessed using the puzzle box assay, and memory performance was studied with novel object recognition and object place recognition assays. In addition, hippocampal slices were prepared 1 week after traumatic brain injury, and long-term potentiation was studied using field recordings in the cornu Ammonis 1 region of slices that were perfused with L-655,708 (100 nM). MEASUREMENTS AND MAIN RESULTS Traumatic brain injury increased the time required to solve difficult but not simple tasks in the puzzle box assay and impaired memory in the novel object recognition and object place recognition assays. L-655,708 improved both problem solving and memory in the traumatic brain injury mice. Traumatic brain injury reduced long-term potentiation in the hippocampal slices, and L-655,708 attenuated this reduction. CONCLUSIONS Pharmacologic inhibition of α5 subunit-containing γ-aminobutyric acid type A receptors attenuated cognitive deficits after traumatic brain injury and enhanced synaptic plasticity in hippocampal slices. Collectively, these results suggest that α5 subunit-containing γ-aminobutyric acid type A receptors are novel targets for pharmacologic treatment of traumatic brain injury-induced persistent cognitive deficits.
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Affiliation(s)
- Shahin Khodaei
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Sinziana Avramescu
- Department of Anesthesia, University of Toronto, Toronto, ON, Canada
- Department of Anesthesia, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Dian-Shi Wang
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Heping Sheng
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Nathan K Chan
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Irene Lecker
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | | | - Gang Lei
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Michael B Dewar
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Paul D Whissell
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Andrew J Baker
- Department of Anesthesia, University of Toronto, Toronto, ON, Canada
- Department of Anesthesia, St. Michael's Hospital, Toronto, ON, Canada
| | - Beverley A Orser
- Department of Physiology, University of Toronto, Toronto, ON, Canada
- Department of Anesthesia, University of Toronto, Toronto, ON, Canada
- Department of Anesthesia, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
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23
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Heo JY, Nam MH, Yoon HH, Kim J, Hwang YJ, Won W, Woo DH, Lee JA, Park HJ, Jo S, Lee MJ, Kim S, Shim JE, Jang DP, Kim KI, Huh SH, Jeong JY, Kowall NW, Lee J, Im H, Park JH, Jang BK, Park KD, Lee HJ, Shin H, Cho IJ, Hwang EM, Kim Y, Kim HY, Oh SJ, Lee SE, Paek SH, Yoon JH, Jin BK, Kweon GR, Shim I, Hwang O, Ryu H, Jeon SR, Lee CJ. Aberrant Tonic Inhibition of Dopaminergic Neuronal Activity Causes Motor Symptoms in Animal Models of Parkinson's Disease. Curr Biol 2020; 30:276-291.e9. [PMID: 31928877 DOI: 10.1016/j.cub.2019.11.079] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 10/19/2019] [Accepted: 11/26/2019] [Indexed: 01/12/2023]
Abstract
Current pharmacological treatments for Parkinson's disease (PD) are focused on symptomatic relief, but not on disease modification, based on the strong belief that PD is caused by irreversible dopaminergic neuronal death. Thus, the concept of the presence of dormant dopaminergic neurons and its possibility as the disease-modifying therapeutic target against PD have not been explored. Here we show that optogenetic activation of substantia nigra pars compacta (SNpc) neurons alleviates parkinsonism in acute PD animal models by recovering tyrosine hydroxylase (TH) from the TH-negative dormant dopaminergic neurons, some of which still express DOPA decarboxylase (DDC). The TH loss depends on reduced dopaminergic neuronal firing under aberrant tonic inhibition, which is attributed to excessive astrocytic GABA. Blocking the astrocytic GABA synthesis recapitulates the therapeutic effect of optogenetic activation. Consistently, SNpc of postmortem PD patients shows a significant population of TH-negative/DDC-positive dormant neurons surrounded by numerous GABA-positive astrocytes. We propose that disinhibiting dormant dopaminergic neurons by blocking excessive astrocytic GABA could be an effective therapeutic strategy against PD.
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Affiliation(s)
- Jun Young Heo
- Center for Neuroscience, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; Department of Medical Science, College of Medicine, Chungnam National University, Daejeon 35015, Korea; Infection Control Convergence Research Center, College of Medicine, Chungnam National University, Daejeon 35015, Korea
| | - Min-Ho Nam
- Center for Neuroscience, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; Department of Science in Korean Medicine, Graduate School, Kyung Hee University, Seoul 02447, Korea
| | - Hyung Ho Yoon
- Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Jeongyeon Kim
- Center for Neuroscience, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; Emotion, Cognition and Behavior Research Group, Korea Brain Research Institute, Daegu 41062, Korea
| | - Yu Jin Hwang
- Center for Neuro-Medicine, Brain Science Institute, KIST, Seoul 02792, Korea
| | - Woojin Won
- Center for Neuroscience, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; KU-KIST Graduate School of Converging Science of Technology, Korea University, Seoul 02841, Korea
| | - Dong Ho Woo
- Center for Neuroscience, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea
| | - Ji Ae Lee
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Hyun-Jung Park
- Department of Science in Korean Medicine, Graduate School, Kyung Hee University, Seoul 02447, Korea
| | - Seonmi Jo
- Center for Neuroscience, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea; Department of Genetic Resources Research, National Marine Biodiversity Institute of Korea, Seocheon 33662, Korea
| | - Min Joung Lee
- Department of Medical Science, College of Medicine, Chungnam National University, Daejeon 35015, Korea; Infection Control Convergence Research Center, College of Medicine, Chungnam National University, Daejeon 35015, Korea
| | - Sunpil Kim
- Center for Neuroscience, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; KU-KIST Graduate School of Converging Science of Technology, Korea University, Seoul 02841, Korea
| | - Jeong-Eun Shim
- Department of Biomedical Engineering, Hanyang University, Seoul 04763, Korea
| | - Dong-Pyo Jang
- Department of Biomedical Engineering, Hanyang University, Seoul 04763, Korea
| | - Kyoung I Kim
- Department of Biochemistry & Molecular Biology, Department of Neuroscience, Neurodegeneration Control Research Center, School of Medicine, Kyung Hee University, Seoul 02447, Korea
| | - Sue H Huh
- Department of Biochemistry & Molecular Biology, Department of Neuroscience, Neurodegeneration Control Research Center, School of Medicine, Kyung Hee University, Seoul 02447, Korea
| | - Jae Y Jeong
- Department of Biochemistry & Molecular Biology, Department of Neuroscience, Neurodegeneration Control Research Center, School of Medicine, Kyung Hee University, Seoul 02447, Korea
| | - Neil W Kowall
- Boston University Alzheimer's Disease Center, Boston University School of Medicine, Boston, MA 02118, USA; Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA; VA Boston Healthcare System, Boston, MA 02132, USA
| | - Junghee Lee
- Boston University Alzheimer's Disease Center, Boston University School of Medicine, Boston, MA 02118, USA; Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA; VA Boston Healthcare System, Boston, MA 02132, USA
| | - Hyeonjoo Im
- Center for Neuroscience, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; Center for Neuro-Medicine, Brain Science Institute, KIST, Seoul 02792, Korea
| | - Jong Hyun Park
- Convergence Research Center for Dementia, KIST, Seoul 02792, Korea
| | - Bo Ko Jang
- Convergence Research Center for Dementia, KIST, Seoul 02792, Korea
| | - Ki Duk Park
- Convergence Research Center for Dementia, KIST, Seoul 02792, Korea
| | - Hyunjoo J Lee
- Center for BioMicrosystems, Brain Science Institute, KIST, Seoul 02792, Korea
| | - Hyogeun Shin
- Center for BioMicrosystems, Brain Science Institute, KIST, Seoul 02792, Korea
| | - Il-Joo Cho
- Center for BioMicrosystems, Brain Science Institute, KIST, Seoul 02792, Korea
| | - Eun Mi Hwang
- Center for Functional Connectomics, KIST, Seoul 02792, Korea
| | - YoungSoo Kim
- Center for Neuro-Medicine, Brain Science Institute, KIST, Seoul 02792, Korea; Department of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, and Integrated Science and Engineering Division, Yonsei University, Incheon 21983, Korea
| | - Hye Yun Kim
- Department of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, and Integrated Science and Engineering Division, Yonsei University, Incheon 21983, Korea
| | - Soo-Jin Oh
- Center for Neuroscience, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; Convergence Research Center for Dementia, KIST, Seoul 02792, Korea
| | - Seung Eun Lee
- Virus Facility, Research Animal Resource Center, KIST, Seoul 02792, Korea
| | - Sun Ha Paek
- Department of Neurosurgery, Seoul National University Hospital, Seoul 03080, Korea
| | - Jong Hyuk Yoon
- Neurodegenerative Diseases Research Group, Korea Brain Research Institute, Daegu 41062, Korea
| | - Byung K Jin
- Department of Biochemistry & Molecular Biology, Department of Neuroscience, Neurodegeneration Control Research Center, School of Medicine, Kyung Hee University, Seoul 02447, Korea
| | - Gi Ryang Kweon
- Department of Medical Science, College of Medicine, Chungnam National University, Daejeon 35015, Korea; Infection Control Convergence Research Center, College of Medicine, Chungnam National University, Daejeon 35015, Korea
| | - Insop Shim
- Department of Science in Korean Medicine, Graduate School, Kyung Hee University, Seoul 02447, Korea
| | - Onyou Hwang
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Hoon Ryu
- Center for Neuroscience, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; Center for Neuro-Medicine, Brain Science Institute, KIST, Seoul 02792, Korea; Boston University Alzheimer's Disease Center, Boston University School of Medicine, Boston, MA 02118, USA; Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA; VA Boston Healthcare System, Boston, MA 02132, USA.
| | - Sang Ryong Jeon
- Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea.
| | - C Justin Lee
- Center for Neuroscience, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; KU-KIST Graduate School of Converging Science of Technology, Korea University, Seoul 02841, Korea; Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Korea.
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24
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Cragnolini AB, Lampitella G, Virtuoso A, Viscovo I, Panetsos F, Papa M, Cirillo G. Regional brain susceptibility to neurodegeneration: what is the role of glial cells? Neural Regen Res 2020; 15:838-842. [PMID: 31719244 PMCID: PMC6990768 DOI: 10.4103/1673-5374.268897] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The main pathological feature of the neurodegenerative diseases is represented by neuronal death that represents the final step of a cascade of adverse/hostile events. Early in the neurodegenerative process, glial cells (including astrocytes, microglial cells, and oligodendrocytes) activate and trigger an insidious neuroinflammatory reaction, metabolic decay, blood brain barrier dysfunction and energy impairment, boosting neuronal death. How these mechanisms might induce selective neuronal death in specific brain areas are far from being elucidated. The last two decades of neurobiological studies have provided evidence of the main role of glial cells in most of the processes of the central nervous system, from development to synaptogenesis, neuronal homeostasis and integration into, highly specific neuro-glial networks. In this mini-review, we moved from in vitro and in vivo models of neurodegeneration to analyze the putative role of glial cells in the early mechanisms of neurodegeneration. We report changes of transcriptional, genetic, morphological, and metabolic activity in astrocytes and microglial cells in specific brain areas before neuronal degeneration, providing evidence in experimental models of neurodegenerative disorders, including Parkinson's and Alzheimer's diseases. Understanding these mechanisms might increase the insight of these processes and pave the way for new specific glia-targeted therapeutic strategies for neurodegenerative disorders.
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Affiliation(s)
- Andrea Beatriz Cragnolini
- Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba; Instituto de Investigaciones Biológicas y Tecnológicas (IIByT), CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Giorgia Lampitella
- Human Anatomy and Laboratory of Morphology of Neuronal Networks, Department of Mental and Physical Health and Preventive Medicine, University of Campania "Luigi Vanvitelli, Naples, Italy
| | - Assunta Virtuoso
- Human Anatomy and Laboratory of Morphology of Neuronal Networks, Department of Mental and Physical Health and Preventive Medicine, University of Campania "Luigi Vanvitelli, Naples, Italy
| | - Immacolata Viscovo
- Human Anatomy and Laboratory of Morphology of Neuronal Networks, Department of Mental and Physical Health and Preventive Medicine, University of Campania "Luigi Vanvitelli, Naples, Italy
| | - Fivos Panetsos
- Neuro-computing & Neuro-robotics Research Group, Universidad Complutense de Madrid; Neural Plasticity Research Group, Instituto Investigación Sanitaria Hospital Clínico San Carlos, Madrid, Spain
| | - Michele Papa
- Human Anatomy and Laboratory of Morphology of Neuronal Networks, Department of Mental and Physical Health and Preventive Medicine, University of Campania "Luigi Vanvitelli, Naples, Italy
| | - Giovanni Cirillo
- Human Anatomy and Laboratory of Morphology of Neuronal Networks, Department of Mental and Physical Health and Preventive Medicine, University of Campania "Luigi Vanvitelli, Naples, Italy
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25
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Chávez CE, Oyarzún JE, Avendaño BC, Mellado LA, Inostroza CA, Alvear TF, Orellana JA. The Opening of Connexin 43 Hemichannels Alters Hippocampal Astrocyte Function and Neuronal Survival in Prenatally LPS-Exposed Adult Offspring. Front Cell Neurosci 2019; 13:460. [PMID: 31680871 PMCID: PMC6797550 DOI: 10.3389/fncel.2019.00460] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 09/27/2019] [Indexed: 01/19/2023] Open
Abstract
Clinical evidence has revealed that children born from mothers exposed to viral and bacterial pathogens during pregnancy are more likely to suffer various neurological disorders including schizophrenia, autism bipolar disorder, major depression, epilepsy, and cerebral palsy. Despite that most research has centered on the impact of prenatal inflammation in neurons and microglia, the potential modifications of astrocytes and neuron-astrocyte communication have received less scrutiny. Here, we evaluated whether prenatally LPS-exposed offspring display alterations in the opening of astrocyte hemichannels and pannexons in the hippocampus, together with changes in neuroinflammation, intracellular Ca2+ and nitric oxide (NO) signaling, gliotransmitter release, cell arborization, and neuronal survival. Ethidium uptake recordings revealed that prenatal LPS exposure enhances the opening of astrocyte Cx43 hemichannels and Panx1 channels in the hippocampus of adult offspring mice. This enhanced channel activity occurred by a mechanism involving a microglia-dependent production of IL-1β/TNF-α and the stimulation of p38 MAP kinase/iNOS/[Ca2+]i-mediated signaling and purinergic/glutamatergic pathways. Noteworthy, the activity of Cx43 hemichannels affected the release of glutamate, [Ca2+]i handling, and morphology of astrocytes, whereas also disturbed neuronal function, including the dendritic arbor and spine density, as well as survival. We speculate that excitotoxic levels of glutamate triggered by the activation of Cx43 hemichannels may contribute to hippocampal neurotoxicity and damage in prenatally LPS-exposed offspring. Therefore, the understanding of how astrocyte-neuron crosstalk is an auspicious avenue toward the development of broad treatments for several neurological disorders observed in children born to women who had a severe infection during gestation.
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Affiliation(s)
- Carolina E Chávez
- Departamento de Neurología, Facultad de Medicina, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Juan E Oyarzún
- Departamento de Neurología, Facultad de Medicina, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Beatriz C Avendaño
- Departamento de Neurología, Facultad de Medicina, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Luis A Mellado
- Departamento de Neurología, Facultad de Medicina, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carla A Inostroza
- Departamento de Neurología, Facultad de Medicina, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Tanhia F Alvear
- Departamento de Neurología, Facultad de Medicina, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Juan A Orellana
- Departamento de Neurología, Facultad de Medicina, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Pontificia Universidad Católica de Chile, Santiago, Chile
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26
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Ultrasonic Neuromodulation via Astrocytic TRPA1. Curr Biol 2019; 29:3386-3401.e8. [PMID: 31588000 DOI: 10.1016/j.cub.2019.08.021] [Citation(s) in RCA: 116] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 07/26/2019] [Accepted: 08/08/2019] [Indexed: 01/07/2023]
Abstract
Low-intensity, low-frequency ultrasound (LILFU) is the next-generation, non-invasive brain stimulation technology for treating various neurological and psychiatric disorders. However, the underlying cellular and molecular mechanism of LILFU-induced neuromodulation has remained unknown. Here, we report that LILFU-induced neuromodulation is initiated by opening of TRPA1 channels in astrocytes. The Ca2+ entry through TRPA1 causes a release of gliotransmitters including glutamate through Best1 channels in astrocytes. The released glutamate activates NMDA receptors in neighboring neurons to elicit action potential firing. Our results reveal an unprecedented mechanism of LILFU-induced neuromodulation, involving TRPA1 as a unique sensor for LILFU and glutamate-releasing Best1 as a mediator of glia-neuron interaction. These discoveries should prove to be useful for optimization of human brain stimulation and ultrasonogenetic manipulations of TRPA1.
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27
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Escartin C, Guillemaud O, Carrillo-de Sauvage MA. Questions and (some) answers on reactive astrocytes. Glia 2019; 67:2221-2247. [PMID: 31429127 DOI: 10.1002/glia.23687] [Citation(s) in RCA: 173] [Impact Index Per Article: 34.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 06/12/2019] [Accepted: 06/28/2019] [Indexed: 02/06/2023]
Abstract
Astrocytes are key cellular partners for neurons in the central nervous system. Astrocytes react to virtually all types of pathological alterations in brain homeostasis by significant morphological and molecular changes. This response was classically viewed as stereotypical and is called astrogliosis or astrocyte reactivity. It was long considered as a nonspecific, secondary reaction to pathological conditions, offering no clues on disease-causing mechanisms and with little therapeutic value. However, many studies over the last 30 years have underlined the crucial and active roles played by astrocytes in physiology, ranging from metabolic support, synapse maturation, and pruning to fine regulation of synaptic transmission. This prompted researchers to explore how these new astrocyte functions were changed in disease, and they reported alterations in many of them (sometimes beneficial, mostly deleterious). More recently, cell-specific transcriptomics revealed that astrocytes undergo massive changes in gene expression when they become reactive. This observation further stressed that reactive astrocytes may be very different from normal, nonreactive astrocytes and could influence disease outcomes. To make the picture even more complex, both normal and reactive astrocytes were shown to be molecularly and functionally heterogeneous. Very little is known about the specific roles that each subtype of reactive astrocytes may play in different disease contexts. In this review, we have interrogated researchers in the field to identify and discuss points of consensus and controversies about reactive astrocytes, starting with their very name. We then present the emerging knowledge on these cells and future challenges in this field.
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Affiliation(s)
- Carole Escartin
- Commissariat à l'Energie Atomique et aux Energies Alternatives, Département de la Recherche Fondamentale, Institut de Biologie François Jacob, MIRCen, Fontenay-aux-Roses, France.,Centre National de la Recherche Scientifique, Univ. Paris Sud, Univ. Paris-Saclay, UMR 9199, Neurodegenerative Disease Laboratory, Fontenay-aux-Roses, France
| | - Océane Guillemaud
- Commissariat à l'Energie Atomique et aux Energies Alternatives, Département de la Recherche Fondamentale, Institut de Biologie François Jacob, MIRCen, Fontenay-aux-Roses, France.,Centre National de la Recherche Scientifique, Univ. Paris Sud, Univ. Paris-Saclay, UMR 9199, Neurodegenerative Disease Laboratory, Fontenay-aux-Roses, France
| | - Maria-Angeles Carrillo-de Sauvage
- Commissariat à l'Energie Atomique et aux Energies Alternatives, Département de la Recherche Fondamentale, Institut de Biologie François Jacob, MIRCen, Fontenay-aux-Roses, France.,Centre National de la Recherche Scientifique, Univ. Paris Sud, Univ. Paris-Saclay, UMR 9199, Neurodegenerative Disease Laboratory, Fontenay-aux-Roses, France
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28
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Aberrant Calcium Signals in Reactive Astrocytes: A Key Process in Neurological Disorders. Int J Mol Sci 2019; 20:ijms20040996. [PMID: 30823575 PMCID: PMC6413203 DOI: 10.3390/ijms20040996] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 02/20/2019] [Accepted: 02/21/2019] [Indexed: 02/06/2023] Open
Abstract
Astrocytes are abundant cells in the brain that regulate multiple aspects of neural tissue homeostasis by providing structural and metabolic support to neurons, maintaining synaptic environments and regulating blood flow. Recent evidence indicates that astrocytes also actively participate in brain functions and play a key role in brain disease by responding to neuronal activities and brain insults. Astrocytes become reactive in response to injury and inflammation, which is typically described as hypertrophy with increased expression of glial fibrillary acidic protein (GFAP). Reactive astrocytes are frequently found in many neurological disorders and are a hallmark of brain disease. Furthermore, reactive astrocytes may drive the initiation and progression of disease processes. Recent improvements in the methods to visualize the activity of reactive astrocytes in situ and in vivo have helped elucidate their functions. Ca2+ signals in reactive astrocytes are closely related to multiple aspects of disease and can be a good indicator of disease severity/state. In this review, we summarize recent findings concerning reactive astrocyte Ca2+ signals. We discuss the molecular mechanisms underlying aberrant Ca2+ signals in reactive astrocytes and the functional significance of aberrant Ca2+ signals in neurological disorders.
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29
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Zhou Z, Ikegaya Y, Koyama R. The Astrocytic cAMP Pathway in Health and Disease. Int J Mol Sci 2019; 20:E779. [PMID: 30759771 PMCID: PMC6386894 DOI: 10.3390/ijms20030779] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 02/06/2019] [Accepted: 02/08/2019] [Indexed: 12/11/2022] Open
Abstract
Astrocytes are major glial cells that play critical roles in brain homeostasis. Abnormalities in astrocytic functions can lead to brain disorders. Astrocytes also respond to injury and disease through gliosis and immune activation, which can be both protective and detrimental. Thus, it is essential to elucidate the function of astrocytes in order to understand the physiology of the brain to develop therapeutic strategies against brain diseases. Cyclic adenosine monophosphate (cAMP) is a major second messenger that triggers various downstream cellular machinery in a wide variety of cells. The functions of astrocytes have also been suggested as being regulated by cAMP. Here, we summarize the possible roles of cAMP signaling in regulating the functions of astrocytes. Specifically, we introduce the ways in which cAMP pathways are involved in astrocyte functions, including (1) energy supply, (2) maintenance of the extracellular environment, (3) immune response, and (4) a potential role as a provider of trophic factors, and we discuss how these cAMP-regulated processes can affect brain functions in health and disease.
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Affiliation(s)
- Zhiwen Zhou
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo Bunkyo-ku, Tokyo 113-0033, Japan.
| | - Yuji Ikegaya
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo Bunkyo-ku, Tokyo 113-0033, Japan.
- Center for Information and Neural Networks, Suita City, Osaka 565-0871, Japan.
| | - Ryuta Koyama
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo Bunkyo-ku, Tokyo 113-0033, Japan.
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30
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Small-chain fatty acid activates astrocytic odorant receptor Olfr920. Biochem Biophys Res Commun 2019; 510:383-387. [PMID: 30711253 DOI: 10.1016/j.bbrc.2019.01.106] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 01/19/2019] [Indexed: 11/21/2022]
Abstract
Odorant receptors are the largest subfamily of G protein-coupled receptors and were recently suggested to play critical roles in nonolfactory tissues. However, the expression and function of odorant receptors in astrocytes, the most abundant cells in the brain, are not well known. We demonstrate that Olfr920 is highly expressed and propose that it functions as a short-chain fatty acid sensor in primary cortical astrocytes. The short-chain fatty acid isobutyric acid (IBA) was identified via a luciferase assay as an Olfr920 ligand. We show that IBA activates the Gs protein-adenylyl cyclase-cAMP pathway via Olfr920 in primary cortical astrocytes by using cAMP and knockdown analyses. In addition, IBA reduces lipopolysaccharide-induced glial fibrillary acidic protein expression in reactive astrocytes. These results suggest that astrocytic Olfr920 is a potential novel target for increased reactive astrocytes.
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31
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Lee N, Sa M, Hong YR, Lee CJ, Koo J. Fatty Acid Increases cAMP-dependent Lactate and MAO-B-dependent GABA Production in Mouse Astrocytes by Activating a G αs Protein-coupled Receptor. Exp Neurobiol 2018; 27:365-376. [PMID: 30429646 PMCID: PMC6221839 DOI: 10.5607/en.2018.27.5.365] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 10/20/2018] [Accepted: 10/24/2018] [Indexed: 12/16/2022] Open
Abstract
Medium-chain fatty acids (MCFAs) are mostly generated from dietary triglycerides and can penetrate the blood-brain barrier. Astrocytes in the brain use MCFAs as an alternative energy source. In addition, MCFAs have various regulatory and signaling functions in astrocytes. However, it is unclear how astrocytes sense and take up MCFAs. This study demonstrates that decanoic acid (DA; C10), a saturated MCFA and a ligand of Gαs protein-coupled receptors (Gαs-GPCRs), is a signaling molecule in energy metabolism in primary astrocytes. cAMP synthesis and lactate release were increased via a putative Gαs-GPCR and transmembrane adenylyl cyclase upon short-term treatment with DA. By contrast, monoamine oxidase B-dependent gamma-aminobutyric acid (GABA) synthesis was increased in primary cortical and hypothalamic astrocytes upon long-term treatment with DA. Thus, astrocytes respond to DA by synthesizing cAMP and releasing lactate upon short-term treatment, and by synthesizing and releasing GABA upon long-term treatment, similar to reactive astrocytes. Our data suggest that astrocytes in the brain play crucial roles in lipid-sensing via GPCRs and modulate neuronal metabolism or activity by releasing lactate via astrocyte-neuron lactate shuttle or GABA to influence neighboring neurons.
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Affiliation(s)
- NaHye Lee
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Korea.,Department of New Biology, DGIST, Daegu 42988, Korea.,Center for Bio-Convergence Spin System, DGIST, Daegu 42988, Korea
| | - Moonsun Sa
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea.,Center for Neuroscience and Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea.,Center for Glia-Neuron Interaction, KIST, Seoul 02792, Korea
| | - Yu Ri Hong
- Department of New Biology, DGIST, Daegu 42988, Korea
| | - C Justin Lee
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea.,Center for Neuroscience and Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea.,Center for Glia-Neuron Interaction, KIST, Seoul 02792, Korea
| | - JaeHyung Koo
- Department of New Biology, DGIST, Daegu 42988, Korea.,Center for Bio-Convergence Spin System, DGIST, Daegu 42988, Korea
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