1
|
Yuan WQ, Huang WP, Jiang YC, Xu H, Duan CS, Chen NH, Liu YJ, Fu XM. The function of astrocytes and their role in neurological diseases. Eur J Neurosci 2023; 58:3932-3961. [PMID: 37831013 DOI: 10.1111/ejn.16160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 09/11/2023] [Accepted: 09/13/2023] [Indexed: 10/14/2023]
Abstract
Astrocytes have countless links with neurons. Previously, astrocytes were only considered a scaffold of neurons; in fact, astrocytes perform a variety of functions, including providing support for neuronal structures and energy metabolism, offering isolation and protection and influencing the formation, function and elimination of synapses. Because of these functions, astrocytes play an critical role in central nervous system (CNS) diseases. The regulation of the secretiory factors, receptors, channels and pathways of astrocytes can effectively inhibit the occurrence and development of CNS diseases, such as neuromyelitis optica (NMO), multiple sclerosis, Alzheimer's disease (AD), Parkinson's disease (PD) and Huntington's disease. The expression of aquaporin 4 in AS is directly related to NMO and indirectly involved in the clearance of Aβ and tau proteins in AD. Connexin 43 has a bidirectional effect on glutamate diffusion at different stages of stroke. Interestingly, astrocytes reduce the occurrence of PD through multiple effects such as secretion of related factors, mitochondrial autophagy and aquaporin 4. Therefore, this review is focused on the structure and function of astrocytes and the correlation between astrocytes and CNS diseases and drug treatment to explore the new functions of astrocytes with the astrocytes as the target. This, in turn, would provide a reference for the development of new drugs to protect neurons and promote the recovery of nerve function.
Collapse
Affiliation(s)
- Wen-Qin Yuan
- College of Pharmacy, Jiangxi University of Chinese Medicine, Nanchang, China
| | - Wei-Peng Huang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica and Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- College of Pharmacy, Minzu University of China, Beijing, China
| | - Yang-Chao Jiang
- College of Pharmacy, Jiangxi University of Chinese Medicine, Nanchang, China
| | - Hao Xu
- College of Economics and Management, Jiangxi University of Chinese Medicine, Nanchang, China
| | - Chong-Shen Duan
- College of Pharmacy, Jiangxi University of Chinese Medicine, Nanchang, China
| | - Nai-Hong Chen
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica and Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Ying-Jiao Liu
- College of Pharmacy, Jiangxi University of Chinese Medicine, Nanchang, China
| | - Xiao-Mei Fu
- College of Pharmacy, Jiangxi University of Chinese Medicine, Nanchang, China
| |
Collapse
|
2
|
Lei L, Wang YT, Hu D, Gai C, Zhang Y. Astroglial Connexin 43-Mediated Gap Junctions and Hemichannels: Potential Antidepressant Mechanisms and the Link to Neuroinflammation. Cell Mol Neurobiol 2023; 43:4023-4040. [PMID: 37875763 DOI: 10.1007/s10571-023-01426-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 10/14/2023] [Indexed: 10/26/2023]
Abstract
Major depression disorder (MDD) is a neuropsychiatric disorder associated with a high suicide rate and a higher disability rate than any other disease. Evidence suggests that the pathological mechanism of MDD is related to astrocyte dysfunction. Depression is mainly associated with the expression of connexin 43 (Cx43) and the function of Cx43-mediated gap junctions and hemichannels in astrocytes. Moreover, neuroinflammation has been a hotspot in research on the pathology of depression, and Cx43-mediated functions are thought to be involved in neuroinflammation-related depression. However, the specific mechanism of Cx43-mediated functions in neuroinflammation-related depression pathology remains unclear. Therefore, this review summarizes and discusses Cx43 expression, the role of gap junction intercellular communication, and its relationship with neuroinflammation in depression. This review also focuses on the effects of antidepressant drugs (e.g., monoamine antidepressants, psychotropic drugs, and N-methyl-D-aspartate receptor antagonists) on Cx43-mediated function and provides evidence for Cx43 as a novel target for the treatment of MDD. The pathogenesis of MDD is related to astrocyte dysfunction, with reduced Cx43 expression, GJ dysfunction, decreased GJIC and reduced BDNF expression in the depressed brain. The effect of Cx43 on neuroinflammation-related depression involving inflammatory cytokines, glutamate excitotoxicity, and HPA axis dysregulation. Antidepressant drugs targeting Cx43 can effectively relieve depressive symptoms.
Collapse
Affiliation(s)
- Lan Lei
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Sunshine Southern Avenue, Fang-Shan District, Beijing, 102488, China
| | - Ya-Ting Wang
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Sunshine Southern Avenue, Fang-Shan District, Beijing, 102488, China
| | - Die Hu
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Sunshine Southern Avenue, Fang-Shan District, Beijing, 102488, China
| | - Cong Gai
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Sunshine Southern Avenue, Fang-Shan District, Beijing, 102488, China
| | - Yi Zhang
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Sunshine Southern Avenue, Fang-Shan District, Beijing, 102488, China.
| |
Collapse
|
3
|
Darvishmolla M, Saeedi N, Tavassoli Z, Heysieattalab S, Janahmadi M, Hosseinmardi N. Maladaptive plasticity induced by morphine is mediated by hippocampal astrocytic Connexin-43. Life Sci 2023; 330:121969. [PMID: 37541575 DOI: 10.1016/j.lfs.2023.121969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 07/16/2023] [Accepted: 07/18/2023] [Indexed: 08/06/2023]
Abstract
AIMS Drug addiction is an aberrant learning process that involves the recruitment of memory systems. We have previously demonstrated that morphine exposure causes maladaptive synaptic plasticity which involved hippocampal glial cells, especially astrocytes. Morphine addiction has been associated with astrocytic connexin 43 (Cx43), which plays a role in synaptic homeostasis. This study aimed to examine the role of hippocampal astrocytic Cx43 in morphine-induced maladaptive plasticity as a mechanism of addiction. MAIN METHODS Male rats were injected with morphine (10 mg/kg) subcutaneously every 12 h for nine days to induce dependence. Cx43 was inhibited by TAT-Gap19 (1 μl/1 nmol) microinjection in the CA1 region of the hippocampus 30 min before each morning morphine injection. Field potential recordings were used to assess synaptic plasticity. fEPSP was recorded from the CA1 area following CA3 stimulation. KEY FINDINGS Electrophysiological results showed that morphine treatment altered baseline synaptic responses. It also appears that morphine treatment augmented long-term potentiation (LTP) compared with the control group. Hippocampal astrocytic Cx43 inhibition, with the TAT-Gap19, undermines these effects of morphine on baseline synaptic responses and LTP. Despite this, long-term depression (LTD) did not differ significantly between the groups. Additionally, in the morphine-receiving group, inhibition of Cx43 significantly reduced the paired-pulse index at an 80-millisecond inter-pulse interval when assessing short-term plasticity. SIGNIFICANCE The results of this study demonstrated that inhibiting Cx43 reduced synaptic plasticity induced by morphine. It can be concluded that hippocampal astrocytes through Cx43 are involved in morphine-induced metaplasticity.
Collapse
Affiliation(s)
- Mahgol Darvishmolla
- Department of Physiology, Medical School, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neurophysiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Negin Saeedi
- Department of Physiology, Medical School, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neurophysiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Zohreh Tavassoli
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | | | - Mahyar Janahmadi
- Department of Physiology, Medical School, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neurophysiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Narges Hosseinmardi
- Department of Physiology, Medical School, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neurophysiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
4
|
Sun N, Cui WQ, Min XM, Zhang GM, Liu JZ, Wu HY. A new perspective on hippocampal synaptic plasticity and post-stroke depression. Eur J Neurosci 2023; 58:2961-2984. [PMID: 37518943 DOI: 10.1111/ejn.16093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 07/01/2023] [Accepted: 07/03/2023] [Indexed: 08/01/2023]
Abstract
Post-stroke depression, a common complication after stroke, severely affects the recovery and quality of life of patients with stroke. Owing to its complex mechanisms, post-stroke depression treatment remains highly challenging. Hippocampal synaptic plasticity is one of the key factors leading to post-stroke depression; however, the precise molecular mechanisms remain unclear. Numerous studies have found that neurotrophic factors, protein kinases and neurotransmitters influence depressive behaviour by modulating hippocampal synaptic plasticity. This review further elaborates on the role of hippocampal synaptic plasticity in post-stroke depression by summarizing recent research and analysing possible molecular mechanisms. Evidence for the correlation between hippocampal mechanisms and post-stroke depression helps to better understand the pathological process of post-stroke depression and improve its treatment.
Collapse
Affiliation(s)
- Ning Sun
- First College of Clinical Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Wen-Qiang Cui
- Department of Neurology, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Xiao-Man Min
- College of Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Guang-Ming Zhang
- College of Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Jia-Zheng Liu
- College of Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Hong-Yun Wu
- Department of Neurology, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, China
| |
Collapse
|
5
|
Wang J, Yang L. The role of exosomes in central nervous system tissue regeneration and repair. Biomed Mater 2023; 18:052003. [PMID: 37399812 DOI: 10.1088/1748-605x/ace39c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 07/03/2023] [Indexed: 07/05/2023]
Abstract
Exosomes are membrane-bound vesicles secreted by various cell types into the extracellular environment and contain kinds of bioactive molecules. These molecules can mediate various biological processes such as cell differentiation, proliferation, and survival, making them attractive for tissue regeneration and repair. Owing to their nanoscale size, bilayer membrane structure, and receptor-mediated transcytosis, exosomes can cross the blood-brain barrier (BBB) and reach the central nervous system (CNS) tissue. Additionally, exosomes can be loaded with exogenous substances after isolation. It has been suggested that exosomes could be used as natural drug carriers to transport therapeutic agents across the BBB and have great potential for CNS disease therapy by promoting tissue regeneration and repair. Herein, we discuss perspectives on therapeutic strategies to treat neurodegenerative disease or spinal cord injury using a variety of cell types-derived exosomes with kinds of exosomal contents, as well as engineering strategies of specific functional and exosome administration routes.
Collapse
Affiliation(s)
- Jingtao Wang
- Guangzhou Xinhua University, No.19 Huamei Road, Guangzhou, Guangdong 510520, People's Republic of China
| | - Lingyan Yang
- Guangzhou Laboratory, No. 9 XingDaoHuanBei Road, Guangzhou International Bio Island, Guangzhou, Guangdong 510005, People's Republic of China
| |
Collapse
|
6
|
Zhang M, Wang ZZ, Chen NH. Connexin 43 Phosphorylation: Implications in Multiple Diseases. Molecules 2023; 28:4914. [PMID: 37446576 DOI: 10.3390/molecules28134914] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 06/16/2023] [Accepted: 06/20/2023] [Indexed: 07/15/2023] Open
Abstract
Connexin 43 (Cx43) is most widely distributed in mammals, especially in the cardiovascular and nervous systems. Its phosphorylation state has been found to be regulated by the action of more than ten kinases and phosphatases, including mitogen-activated protein kinase/extracellular signaling and regulating kinase signaling. In addition, the phosphorylation status of different phosphorylation sites affects its own synthesis and assembly and the function of the gap junctions (GJs) to varying degrees. The phosphorylation of Cx43 can affect the permeability, electrical conductivity, and gating properties of GJs, thereby having various effects on intercellular communication and affecting physiological or pathological processes in vitro and in vivo. Therefore, clarifying the relationship between Cx43 phosphorylation and specific disease processes will help us better understand the disease. Based on the above clinical and preclinical findings, we present in this review the functional significance of Cx43 phosphorylation in multiple diseases and discuss the potential of Cx43 as a drug target in Cx43-related disease pathophysiology, with an emphasis on the importance of connexin 43 as an emerging therapeutic target in cardiac and neuroprotection.
Collapse
Affiliation(s)
- Meng Zhang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100050, China
| | - Zhen-Zhen Wang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100050, China
| | - Nai-Hong Chen
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100050, China
| |
Collapse
|
7
|
Alotaibi G, Khan A, Ronan PJ, Lutfy K, Rahman S. Glial Glutamate Transporter Modulation Prevents Development of Complete Freund's Adjuvant-Induced Hyperalgesia and Allodynia in Mice. Brain Sci 2023; 13:brainsci13050807. [PMID: 37239279 DOI: 10.3390/brainsci13050807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 05/12/2023] [Accepted: 05/13/2023] [Indexed: 05/28/2023] Open
Abstract
Glial glutamate transporter (GLT-1) modulation in the hippocampus and anterior cingulate cortex (ACC) is critically involved in nociceptive pain. The objective of the study was to investigate the effects of 3-[[(2-methylphenyl) methyl] thio]-6-(2-pyridinyl)-pyridazine (LDN-212320), a GLT-1 activator, against microglial activation induced by complete Freund's adjuvant (CFA) in a mouse model of inflammatory pain. Furthermore, the effects of LDN-212320 on the protein expression of glial markers, such as ionized calcium-binding adaptor molecule 1 (Iba1), cluster of differentiation molecule 11b (CD11b), mitogen-activated protein kinases (p38), astroglial GLT-1, and connexin 43 (CX43), were measured in the hippocampus and ACC following CFA injection using the Western blot analysis and immunofluorescence assay. The effects of LDN-212320 on the pro-inflammatory cytokine interleukin-1β (IL-1β) in the hippocampus and ACC were also assessed using an enzyme-linked immunosorbent assay. Pretreatment with LDN-212320 (20 mg/kg) significantly reduced the CFA-induced tactile allodynia and thermal hyperalgesia. The anti-hyperalgesic and anti-allodynic effects of LDN-212320 were reversed by the GLT-1 antagonist DHK (10 mg/kg). Pretreatment with LDN-212320 significantly reduced CFA-induced microglial Iba1, CD11b, and p38 expression in the hippocampus and ACC. LDN-212320 markedly modulated astroglial GLT-1, CX43, and, IL-1β expression in the hippocampus and ACC. Overall, these results suggest that LDN-212320 prevents CFA-induced allodynia and hyperalgesia by upregulating astroglial GLT-1 and CX43 expression and decreasing microglial activation in the hippocampus and ACC. Therefore, LDN-212320 could be developed as a novel therapeutic drug candidate for chronic inflammatory pain.
Collapse
Affiliation(s)
- Ghallab Alotaibi
- Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University, Brookings, SD 57007, USA
| | - Amna Khan
- Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University, Brookings, SD 57007, USA
| | - Patrick J Ronan
- Research Service, Sioux Falls VA Healthcare System, Sioux Falls, SD 57105, USA
- Department of Psychiatry and Basic Biomedical Sciences, University of South Dakota Sanford School of Medicine, Sioux Falls, SD 57105, USA
| | - Kabirullah Lutfy
- College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, USA
| | - Shafiqur Rahman
- Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University, Brookings, SD 57007, USA
- Research Service, Sioux Falls VA Healthcare System, Sioux Falls, SD 57105, USA
| |
Collapse
|
8
|
Cheung G, Chever O, Rollenhagen A, Quenech'du N, Ezan P, Lübke JHR, Rouach N. Astroglial Connexin 43 Regulates Synaptic Vesicle Release at Hippocampal Synapses. Cells 2023; 12:cells12081133. [PMID: 37190042 DOI: 10.3390/cells12081133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 04/01/2023] [Accepted: 04/03/2023] [Indexed: 05/17/2023] Open
Abstract
Connexin 43, an astroglial gap junction protein, is enriched in perisynaptic astroglial processes and plays major roles in synaptic transmission. We have previously found that astroglial Cx43 controls synaptic glutamate levels and allows for activity-dependent glutamine release to sustain physiological synaptic transmissions and cognitiogns. However, whether Cx43 is important for the release of synaptic vesicles, which is a critical component of synaptic efficacy, remains unanswered. Here, using transgenic mice with a glial conditional knockout of Cx43 (Cx43-/-), we investigate whether and how astrocytes regulate the release of synaptic vesicles from hippocampal synapses. We report that CA1 pyramidal neurons and their synapses develop normally in the absence of astroglial Cx43. However, a significant impairment in synaptic vesicle distribution and release dynamics were observed. In particular, the FM1-43 assays performed using two-photon live imaging and combined with multi-electrode array stimulation in acute hippocampal slices, revealed a slower rate of synaptic vesicle release in Cx43-/- mice. Furthermore, paired-pulse recordings showed that synaptic vesicle release probability was also reduced and is dependent on glutamine supply via Cx43 hemichannel (HC). Taken together, we have uncovered a role for Cx43 in regulating presynaptic functions by controlling the rate and probability of synaptic vesicle release. Our findings further highlight the significance of astroglial Cx43 in synaptic transmission and efficacy.
Collapse
Affiliation(s)
- Giselle Cheung
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, 75231 Paris, France
| | - Oana Chever
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, 75231 Paris, France
| | - Astrid Rollenhagen
- Institute for Neuroscience and Medicine INM-10, Research Center Jülich, 52428 Jülich, Germany
- Jülich-Aachen Research Alliance Translational Brain Medicine, 52056 Aachen, Germany
| | - Nicole Quenech'du
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, 75231 Paris, France
| | - Pascal Ezan
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, 75231 Paris, France
| | - Joachim H R Lübke
- Institute for Neuroscience and Medicine INM-10, Research Center Jülich, 52428 Jülich, Germany
- Jülich-Aachen Research Alliance Translational Brain Medicine, 52056 Aachen, Germany
- Department of Psychiatry, Psychotherapy and Psychosomatics, Rheinisch-Westfaelische Technische Hochschule Aachen University, 52056 Aachen, Germany
| | - Nathalie Rouach
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, 75231 Paris, France
| |
Collapse
|
9
|
Connexins Signatures of the Neurovascular Unit and Their Physio-Pathological Functions. Int J Mol Sci 2022; 23:ijms23179510. [PMID: 36076908 PMCID: PMC9455936 DOI: 10.3390/ijms23179510] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 08/19/2022] [Accepted: 08/21/2022] [Indexed: 11/16/2022] Open
Abstract
Central nervous system (CNS) homeostasis is closely linked to the delicate balance of the microenvironment in which different cellular components of the neurovascular unit (NVU) coexist. Intercellular communication plays a pivotal role in exchanges of signaling molecules and mediators essential for survival functions, as well as in the removal of disturbing elements that can lead to related pathologies. The specific signatures of connexins (Cxs), proteins which form either gap junctions (GJs) or hemichannels (HCs), represent the biological substrate of the pathophysiological balance. Connexin 43 (Cx43) is undoubtedly one of the most important factors in glia–neuro–vascular crosstalk. Herein, Cxs signatures of every NVU component are highlighted and their critical influence on functional processes in healthy and pathological conditions of nervous microenvironment is reviewed.
Collapse
|
10
|
Dincã DM, Lallemant L, González-Barriga A, Cresto N, Braz SO, Sicot G, Pillet LE, Polvèche H, Magneron P, Huguet-Lachon A, Benyamine H, Azotla-Vilchis CN, Agonizantes-Juárez LE, Tahraoui-Boris J, Martinat C, Hernández-Hernández O, Auboeuf D, Rouach N, Bourgeois CF, Gourdon G, Gomes-Pereira M. Myotonic dystrophy RNA toxicity alters morphology, adhesion and migration of mouse and human astrocytes. Nat Commun 2022; 13:3841. [PMID: 35789154 PMCID: PMC9253038 DOI: 10.1038/s41467-022-31594-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 06/21/2022] [Indexed: 11/24/2022] Open
Abstract
Brain dysfunction in myotonic dystrophy type 1 (DM1), the prototype of toxic RNA disorders, has been mainly attributed to neuronal RNA misprocessing, while little attention has been given to non-neuronal brain cells. Here, using a transgenic mouse model of DM1 that expresses mutant RNA in various brain cell types (neurons, astroglia, and oligodendroglia), we demonstrate that astrocytes exhibit impaired ramification and polarization in vivo and defects in adhesion, spreading, and migration. RNA-dependent toxicity and phenotypes are also found in human transfected glial cells. In line with the cell phenotypes, molecular analyses reveal extensive expression and accumulation of toxic RNA in astrocytes, which result in RNA spliceopathy that is more severe than in neurons. Astrocyte missplicing affects primarily transcripts that regulate cell adhesion, cytoskeleton, and morphogenesis, and it is confirmed in human brain tissue. Our findings demonstrate that DM1 impacts astrocyte cell biology, possibly compromising their support and regulation of synaptic function. Myotonic dystrophy type 1 (DM1) is characterized by debilitating neurological symptoms. Dinca et al. demonstrate the pronounced impact of DM1 on the morphology and RNA metabolism of astrocytes. Their findings suggest astroglial pathology in DM1 brain dysfunction.
Collapse
Affiliation(s)
- Diana M Dincã
- Sorbonne Université, Inserm, Centre de Recherche en Myologie, 75013, Paris, France
| | - Louison Lallemant
- Sorbonne Université, Inserm, Centre de Recherche en Myologie, 75013, Paris, France
| | | | - Noémie Cresto
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, Inserm, Labex Memolife, 75005, Paris, France
| | - Sandra O Braz
- Sorbonne Université, Inserm, Centre de Recherche en Myologie, 75013, Paris, France.,Inserm UMR1163, Institut Imagine, Université Paris Cite, 75015, Paris, France
| | - Géraldine Sicot
- Sorbonne Université, Inserm, Centre de Recherche en Myologie, 75013, Paris, France
| | - Laure-Elise Pillet
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, Inserm, Labex Memolife, 75005, Paris, France.,Doctoral School N°562, Paris Descartes University, Paris, 75006, France
| | - Hélène Polvèche
- Inserm/UEVE UMR861, Université Paris Saclay I-STEM, 91110, Corbeil-Essonnes, France
| | - Paul Magneron
- Sorbonne Université, Inserm, Centre de Recherche en Myologie, 75013, Paris, France
| | - Aline Huguet-Lachon
- Sorbonne Université, Inserm, Centre de Recherche en Myologie, 75013, Paris, France
| | - Hélène Benyamine
- Sorbonne Université, Inserm, Centre de Recherche en Myologie, 75013, Paris, France
| | - Cuauhtli N Azotla-Vilchis
- Laboratory of Genomic Medicine, Department of Genetics, National Rehabilitation Institute (INR-LGII), Mexico City, Mexico
| | - Luis E Agonizantes-Juárez
- Laboratory of Genomic Medicine, Department of Genetics, National Rehabilitation Institute (INR-LGII), Mexico City, Mexico
| | - Julie Tahraoui-Boris
- Inserm/UEVE UMR861, Université Paris Saclay I-STEM, 91110, Corbeil-Essonnes, France
| | - Cécile Martinat
- Inserm/UEVE UMR861, Université Paris Saclay I-STEM, 91110, Corbeil-Essonnes, France
| | - Oscar Hernández-Hernández
- Laboratory of Genomic Medicine, Department of Genetics, National Rehabilitation Institute (INR-LGII), Mexico City, Mexico
| | - Didier Auboeuf
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allée d'Italie, 69364, Lyon, France
| | - Nathalie Rouach
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, Inserm, Labex Memolife, 75005, Paris, France
| | - Cyril F Bourgeois
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allée d'Italie, 69364, Lyon, France
| | - Geneviève Gourdon
- Sorbonne Université, Inserm, Centre de Recherche en Myologie, 75013, Paris, France.
| | - Mário Gomes-Pereira
- Sorbonne Université, Inserm, Centre de Recherche en Myologie, 75013, Paris, France.
| |
Collapse
|
11
|
Linsambarth S, Carvajal FJ, Moraga‐Amaro R, Mendez L, Tamburini G, Jimenez I, Verdugo DA, Gómez GI, Jury N, Martínez P, Zundert B, Varela‐Nallar L, Retamal MA, Martin C, Altenberg GA, Fiori MC, Cerpa W, Orellana JA, Stehberg J. Astroglial gliotransmitters released via Cx43 hemichannels regulate NMDAR‐dependent transmission and short‐term fear memory in the basolateral amygdala. FASEB J 2022; 36:e22134. [DOI: 10.1096/fj.202100798rr] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 12/16/2021] [Accepted: 12/17/2021] [Indexed: 11/11/2022]
Affiliation(s)
- Sergio Linsambarth
- Laboratorio de Neurobiología Instituto de Ciencias Biomédicas Facultad de Medicina y Facultad de Ciencias de la Vida Universidad Andres Bello Santiago Chile
| | - Francisco J. Carvajal
- Laboratorio de Función y Patología Neuronal Departamento de Biología Celular y Molecular Facultad de Ciencias Biológicas Pontificia Universidad Católica de Chile Santiago Chile
| | - Rodrigo Moraga‐Amaro
- Laboratorio de Neurobiología Instituto de Ciencias Biomédicas Facultad de Medicina y Facultad de Ciencias de la Vida Universidad Andres Bello Santiago Chile
| | - Luis Mendez
- Laboratorio de Neurobiología Instituto de Ciencias Biomédicas Facultad de Medicina y Facultad de Ciencias de la Vida Universidad Andres Bello Santiago Chile
| | - Giovanni Tamburini
- Laboratorio de Neurobiología Instituto de Ciencias Biomédicas Facultad de Medicina y Facultad de Ciencias de la Vida Universidad Andres Bello Santiago Chile
| | - Ivanka Jimenez
- Laboratorio de Neurobiología Instituto de Ciencias Biomédicas Facultad de Medicina y Facultad de Ciencias de la Vida Universidad Andres Bello Santiago Chile
| | - Daniel Antonio Verdugo
- Laboratorio de Neurobiología Instituto de Ciencias Biomédicas Facultad de Medicina y Facultad de Ciencias de la Vida Universidad Andres Bello Santiago Chile
| | - Gonzalo I. Gómez
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud Universidad Autónoma de Chile Santiago Chile
| | - Nur Jury
- Instituto de Ciencias Biomédicas Facultad de Medicina y Facultad de Ciencias de la Vida Universidad Andres Bello Santiago Chile
| | - Pablo Martínez
- Instituto de Ciencias Biomédicas Facultad de Medicina y Facultad de Ciencias de la Vida Universidad Andres Bello Santiago Chile
| | - Brigitte Zundert
- Instituto de Ciencias Biomédicas Facultad de Medicina y Facultad de Ciencias de la Vida Universidad Andres Bello Santiago Chile
| | - Lorena Varela‐Nallar
- Instituto de Ciencias Biomédicas Facultad de Medicina y Facultad de Ciencias de la Vida Universidad Andres Bello Santiago Chile
| | - Mauricio A. Retamal
- Centro de Fisiología Celular e Integrativa. Facultad de Medicina Clínica Alemana Universidad del Desarrollo Santiago Chile
| | - Claire Martin
- Unité de Biologie Fonctionnelle et Adaptative Centre National la Recherche Scientifique Unité Mixte de Recherche 8251 Université Paris Diderot, Sorbonne Paris Cité Paris France
| | - Guillermo A. Altenberg
- Department of Cell Physiology and Molecular Biophysics Center for Membrane Protein Research Texas Tech University Health Sciences Center Lubbock Texas USA
| | - Mariana C. Fiori
- Department of Cell Physiology and Molecular Biophysics Center for Membrane Protein Research Texas Tech University Health Sciences Center Lubbock Texas USA
| | - Waldo Cerpa
- Laboratorio de Función y Patología Neuronal Departamento de Biología Celular y Molecular Facultad de Ciencias Biológicas Pontificia Universidad Católica de Chile Santiago Chile
| | - Juan A. Orellana
- Departamento de Neurología Escuela de Medicina Pontificia Universidad Católica de Chile Santiago Chile
| | - Jimmy Stehberg
- Laboratorio de Neurobiología Instituto de Ciencias Biomédicas Facultad de Medicina y Facultad de Ciencias de la Vida Universidad Andres Bello Santiago Chile
| |
Collapse
|
12
|
Involvement of Hippocampal Astrocytic Connexin-43 in Morphine dependence. Physiol Behav 2022; 247:113710. [DOI: 10.1016/j.physbeh.2022.113710] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 01/17/2022] [Accepted: 01/18/2022] [Indexed: 11/20/2022]
|
13
|
Tao XD, Liu ZR, Zhang YQ, Zhang XH. Connexin43 hemichannels contribute to working memory and excitatory synaptic transmission of pyramidal neurons in the prefrontal cortex of rats. Life Sci 2021; 286:120049. [PMID: 34662549 DOI: 10.1016/j.lfs.2021.120049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 10/08/2021] [Accepted: 10/08/2021] [Indexed: 11/30/2022]
Abstract
The gap junction is essential for the communication between astrocytes and neurons by various connexins. Connexin43 hemichannels (Cx43 HCs), one of important subunits of gap junction protein, is highly expressed in astrocytes. It has been demonstrated that Cx43 HCs is involved in synaptic plasticity and learning and memory. However, whether the role of Cx43 HCs in the prefrontal cortex (PFC), a key brain region mediating cognitive and executive functions including working memory, still remains unclear. Here, we investigate that the role of Cx43 HCs in working memory through pharmacological inhibition of Cx43 HCs in the PFC. Gap26, a specific hemichannels blocker for Cx43 HCs, was bilaterally infused into the prelimbic (PrL) area of the PFC and then spatial working memory was examined in delayed alternation task in T-maze. Furthermore, the effect of Gap26 on synaptic transmission of prefrontal pyramidal neurons was examined using whole-cell patch recording in slice containing PFC. The demonstrate that inhibition of prefrontal cortex Cx43 HCs impairs the working memory and excitatory synaptic transmission of PFC neurons, suggesting that Cx43 HCs in the PFC contributes to working memory and excitatory synaptic transmission of neurons in rats.
Collapse
Affiliation(s)
- Xiao-Dong Tao
- Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Zhao-Rui Liu
- Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Yu-Qiu Zhang
- Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Xue-Han Zhang
- Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China.
| |
Collapse
|
14
|
Association Between Adenosine A 2A Receptors and Connexin 43 Regulates Hemichannels Activity and ATP Release in Astrocytes Exposed to Amyloid-β Peptides. Mol Neurobiol 2021; 58:6232-6248. [PMID: 34476674 DOI: 10.1007/s12035-021-02538-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 08/17/2021] [Indexed: 12/31/2022]
Abstract
Increasing evidence implicates astrocytes and the associated purinergic modulation in Alzheimer's disease (AD), characterized by cognitive deficits involving the extracellular amyloid-β peptides (Aβ) accumulation. Aβ can affect astrocytic gliotransmitters release, namely ATP, which is rapidly metabolized into adenosine by ecto-5'-nucleotidase, CD73, resulting in adenosine A2A receptors (A2AR) activation that bolsters neurodegeneration. AD's brains exhibit an upregulation of A2AR and of connexin 43 (Cx43), which in astrocytes forms hemichannels that can mediate ATP release. However, a coupling between astrocytic A2AR and Cx43 remains to be established. This was now investigated using astrocytic primary cultures exposed to Aβ1-42 peptides. Aβ triggered ATP release through Cx43 hemichannels, a process blocked by A2AR antagonists and mimicked by selective A2AR activation. A2AR directly regulated hemichannels activity and prevented Cx43 upregulation and phosphorylation observed in Aβ1-42-exposed astrocytes. Moreover, a proximity ligand assay revealed a physical association between astrocytic A2AR and Cx43. Finally, the blockade of CD73-mediated extracellular formation of ATP-derived adenosine prevented the Aβ-induced increase of Cx43 hemichannel activity and of ATP release. Overall, the data identify a feed-forward loop involving astrocytic A2AR and Cx43 hemichannels, whereby A2AR increase Cx43 hemichannel activity leading to increased ATP release, which is converted into adenosine by CD73, sustaining the increased astrocytic A2AR activity in AD-like conditions.
Collapse
|
15
|
Baldwin KT, Tan CX, Strader ST, Jiang C, Savage JT, Elorza-Vidal X, Contreras X, Rülicke T, Hippenmeyer S, Estévez R, Ji RR, Eroglu C. HepaCAM controls astrocyte self-organization and coupling. Neuron 2021; 109:2427-2442.e10. [PMID: 34171291 PMCID: PMC8547372 DOI: 10.1016/j.neuron.2021.05.025] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 04/19/2021] [Accepted: 05/19/2021] [Indexed: 10/21/2022]
Abstract
Astrocytes extensively infiltrate the neuropil to regulate critical aspects of synaptic development and function. This process is regulated by transcellular interactions between astrocytes and neurons via cell adhesion molecules. How astrocytes coordinate developmental processes among one another to parse out the synaptic neuropil and form non-overlapping territories is unknown. Here we identify a molecular mechanism regulating astrocyte-astrocyte interactions during development to coordinate astrocyte morphogenesis and gap junction coupling. We show that hepaCAM, a disease-linked, astrocyte-enriched cell adhesion molecule, regulates astrocyte competition for territory and morphological complexity in the developing mouse cortex. Furthermore, conditional deletion of Hepacam from developing astrocytes significantly impairs gap junction coupling between astrocytes and disrupts the balance between synaptic excitation and inhibition. Mutations in HEPACAM cause megalencephalic leukoencephalopathy with subcortical cysts in humans. Therefore, our findings suggest that disruption of astrocyte self-organization mechanisms could be an underlying cause of neural pathology.
Collapse
Affiliation(s)
- Katherine T Baldwin
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA.
| | - Christabel X Tan
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Samuel T Strader
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Changyu Jiang
- Department of Anesthesiology and Center for Translational Pain Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Justin T Savage
- Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Xabier Elorza-Vidal
- Unitat de Fisiología, Departament de Ciències Fisiològiques, IDIBELL-Institute of Neurosciences, Universitat de Barcelona, L'Hospitalet de Llobregat, Spain
| | - Ximena Contreras
- Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria
| | - Thomas Rülicke
- Institute of Laboratory Animal Science, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Simon Hippenmeyer
- Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria
| | - Raúl Estévez
- Unitat de Fisiología, Departament de Ciències Fisiològiques, IDIBELL-Institute of Neurosciences, Universitat de Barcelona, L'Hospitalet de Llobregat, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII, Madrid, Spain
| | - Ru-Rong Ji
- Department of Anesthesiology and Center for Translational Pain Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Cagla Eroglu
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA; Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA; Duke Institute for Brain Sciences (DIBS), Durham, NC 27710, USA; Duke University Regeneration Next Initiative, Durham, NC 27710, USA.
| |
Collapse
|
16
|
Mazaud D, Capano A, Rouach N. The many ways astroglial connexins regulate neurotransmission and behavior. Glia 2021; 69:2527-2545. [PMID: 34101261 DOI: 10.1002/glia.24040] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 05/17/2021] [Accepted: 05/21/2021] [Indexed: 12/18/2022]
Abstract
Astrocytes have emerged as major players in the brain, contributing to many functions such as energy supply, neurotransmission, and behavior. They accomplish these functions in part via their capacity to form widespread intercellular networks and to release neuroactive factors, which can modulate neurotransmission at different levels, from individual synapses to neuronal networks. The extensive network communication of astrocytes is primarily mediated by gap junction channels composed of two connexins, Cx30 and Cx43, which present distinct temporal and spatial expression patterns. Yet, astroglial connexins are also involved in direct exchange with the extracellular space via hemichannels, as well as in adhesion and signaling processes via unconventional nonchannel functions. Accumulating evidence indicate that astrocytes modulate neurotransmission and behavior through these diverse connexin functions. We here review the many ways astroglial connexins regulate neuronal activity from the molecular level to behavior.
Collapse
Affiliation(s)
- David Mazaud
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France
| | - Anna Capano
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France.,Doctoral School N°158, Sorbonne University, Paris, France
| | - Nathalie Rouach
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France
| |
Collapse
|
17
|
Rurak GM, Woodside B, Aguilar-Valles A, Salmaso N. Astroglial cells as neuroendocrine targets in forebrain development: Implications for sex differences in psychiatric disease. Front Neuroendocrinol 2021; 60:100897. [PMID: 33359797 DOI: 10.1016/j.yfrne.2020.100897] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 12/05/2020] [Accepted: 12/15/2020] [Indexed: 12/23/2022]
Abstract
Astroglial cells are the most abundant cell type in the mammalian brain. They are implicated in almost every aspect of brain physiology, including maintaining homeostasis, building and maintaining the blood brain barrier, and the development and maturation of neuronal networks. Critically, astroglia also express receptors for gonadal sex hormones, respond rapidly to gonadal hormones, and are able to synthesize hormones. Thus, they are positioned to guide and mediate sexual differentiation of the brain, particularly neuronal networks in typical and pathological conditions. In this review, we describe astroglial involvement in the organization and development of the brain, and consider known sex differences in astroglial responses to understand how astroglial cell-mediated organization may play a role in forebrain sexual dimorphisms in human populations. Finally, we consider how sexually dimorphic astroglial responses and functions in development may lead to sex differences in vulnerability for neuropsychiatric disorders.
Collapse
Affiliation(s)
- Gareth M Rurak
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada
| | - Barbara Woodside
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada; Concordia University, Montreal, Quebec, Canada
| | | | - Natalina Salmaso
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada.
| |
Collapse
|
18
|
Mesnil M, Defamie N, Naus C, Sarrouilhe D. Brain Disorders and Chemical Pollutants: A Gap Junction Link? Biomolecules 2020; 11:biom11010051. [PMID: 33396565 PMCID: PMC7824109 DOI: 10.3390/biom11010051] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 12/22/2020] [Accepted: 12/23/2020] [Indexed: 02/07/2023] Open
Abstract
The incidence of brain pathologies has increased during last decades. Better diagnosis (autism spectrum disorders) and longer life expectancy (Parkinson's disease, Alzheimer's disease) partly explain this increase, while emerging data suggest pollutant exposures as a possible but still underestimated cause of major brain disorders. Taking into account that the brain parenchyma is rich in gap junctions and that most pollutants inhibit their function; brain disorders might be the consequence of gap-junctional alterations due to long-term exposures to pollutants. In this article, this hypothesis is addressed through three complementary aspects: (1) the gap-junctional organization and connexin expression in brain parenchyma and their function; (2) the effect of major pollutants (pesticides, bisphenol A, phthalates, heavy metals, airborne particles, etc.) on gap-junctional and connexin functions; (3) a description of the major brain disorders categorized as neurodevelopmental (autism spectrum disorders, attention deficit hyperactivity disorders, epilepsy), neurobehavioral (migraines, major depressive disorders), neurodegenerative (Parkinson's and Alzheimer's diseases) and cancers (glioma), in which both connexin dysfunction and pollutant involvement have been described. Based on these different aspects, the possible involvement of pollutant-inhibited gap junctions in brain disorders is discussed for prenatal and postnatal exposures.
Collapse
Affiliation(s)
- Marc Mesnil
- Laboratoire STIM, ERL7003 CNRS-Université de Poitiers, 1 rue G. Bonnet–TSA 51 106, 86073 Poitiers, France; (M.M.); (N.D.)
| | - Norah Defamie
- Laboratoire STIM, ERL7003 CNRS-Université de Poitiers, 1 rue G. Bonnet–TSA 51 106, 86073 Poitiers, France; (M.M.); (N.D.)
| | - Christian Naus
- Faculty of Medicine, Department of Cellular & Physiological Sciences, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T1Z3, Canada;
| | - Denis Sarrouilhe
- Laboratoire de Physiologie Humaine, Faculté de Médecine et Pharmacie, 6 rue de La Milétrie, bât D1, TSA 51115, 86073 Poitiers, France
- Correspondence: ; Tel.: +33-5-49-45-43-58
| |
Collapse
|
19
|
Portal B, Guiard BP. [Role of astrocytic connexins in the regulation of extracellular glutamate levels: implication for the treatment of major depressive episodes]. Biol Aujourdhui 2020; 214:71-83. [PMID: 33357364 DOI: 10.1051/jbio/2020008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Indexed: 11/14/2022]
Abstract
Major depression is a psychiatric disorder relying on different neurobiological mechanisms. In particular, a hypersensitivity of the hypothalamic-pituitary-adrenal axis leading to an excess of cortisol in blood and a deficit in monoaminergic neurotransmission have been associated with mood disorders. In keeping with these mechanisms, currently available antidepressant drugs act by increasing the extracellular levels of monoamines in the synaptic cleft. Since the discovery of the rapid and long-lasting antidepressant effects of ketamine, an NMDA receptor antagonist, a growing attention in psychiatry is paid to the pharmacological tools able to attenuate glutamatergic neurotransmission. Astrocytes play an important role in the excitatory/inhibitory balance of the central nervous system through the regulation of glutamate reuptake and secretion. Interestingly, the release of this excitatory amino acid is controlled, at least in part, by plasma membrane proteins (i.e. connexins) that cluster together to form gap junctions or hemichannels. Preclinical evidence suggests that these functional entities play a critical role in emotional behaviour. After a brief overview of the literature on mood disorders and related treatments, this review describes the role of astrocytes and connexins in glutamatergic neurotransmission and major depression. Moreover, we highlight the arguments supporting the therapeutic potential of connexins blockers but also the practical difficulties to target the hemichannels while maintaining gap junctions intact.
Collapse
Affiliation(s)
- Benjamin Portal
- Centre de Recherches sur la Cognition Animale, Centre de Biologie Intégrative, Université de Toulouse, CNRS, 31000 Toulouse, France
| | - Bruno P Guiard
- Centre de Recherches sur la Cognition Animale, Centre de Biologie Intégrative, Université de Toulouse, CNRS, 31000 Toulouse, France
| |
Collapse
|
20
|
Lapato AS, Thompson SM, Parra K, Tiwari-Woodruff SK. Astrocyte Glutamate Uptake and Water Homeostasis Are Dysregulated in the Hippocampus of Multiple Sclerosis Patients With Seizures. ASN Neuro 2020; 12:1759091420979604. [PMID: 33297722 PMCID: PMC7734542 DOI: 10.1177/1759091420979604] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
While seizure disorders are more prevalent among multiple sclerosis (MS) patients than the population overall and prognosticate earlier death & disability, their etiology remains unclear. Translational data indicate perturbed expression of astrocytic molecules contributing to homeostatic neuronal excitability, including water channels (AQP4) and synaptic glutamate transporters (EAAT2), in a mouse model of MS with seizures (MS+S). However, astrocytes in MS+S have not been examined. To assess the translational relevance of astrocyte dysfunction observed in a mouse model of MS+S, demyelinated lesion burden, astrogliosis, and astrocytic biomarkers (AQP4/EAAT2/ connexin-CX43) were evaluated by immunohistochemistry in postmortem hippocampi from MS & MS+S donors. Lesion burden was comparable in MS & MS+S cohorts, but astrogliosis was elevated in MS+S CA1 with a concomitant decrease in EAAT2 signal intensity. AQP4 signal declined in MS+S CA1 & CA3 with a loss of perivascular AQP4 in CA1. CX43 expression was increased in CA3. Together, these data suggest that hippocampal astrocytes from MS+S patients display regional differences in expression of molecules associated with glutamate buffering and water homeostasis that could exacerbate neuronal hyperexcitability. Importantly, mislocalization of CA1 perivascular AQP4 seen in MS+S is analogous to epileptic hippocampi without a history of MS, suggesting convergent pathophysiology. Furthermore, as neuropathology was concentrated in MS+S CA1, future study is warranted to determine the pathophysiology driving regional differences in glial function in the context of seizures during demyelinating disease.
Collapse
Affiliation(s)
- Andrew S Lapato
- Division of Biomedical Sciences, UCR School of Medicine, Riverside, California, United States.,Center for Glial-Neuronal Interaction, UCR School of Medicine, Riverside, California, United States
| | - Sarah M Thompson
- Division of Biomedical Sciences, UCR School of Medicine, Riverside, California, United States
| | - Karen Parra
- Division of Biomedical Sciences, UCR School of Medicine, Riverside, California, United States
| | - Seema K Tiwari-Woodruff
- Division of Biomedical Sciences, UCR School of Medicine, Riverside, California, United States.,Center for Glial-Neuronal Interaction, UCR School of Medicine, Riverside, California, United States.,Department of Neuroscience, UCR School of Medicine, Riverside, California, United States
| |
Collapse
|
21
|
Blockade of Glial Connexin 43 Hemichannels Reduces Food Intake. Cells 2020; 9:cells9112387. [PMID: 33142723 PMCID: PMC7693394 DOI: 10.3390/cells9112387] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 10/20/2020] [Accepted: 10/26/2020] [Indexed: 12/16/2022] Open
Abstract
The metabolic syndrome, which comprises obesity and diabetes, is a major public health problem and the awareness of energy homeostasis control remains an important worldwide issue. The energy balance is finely regulated by the central nervous system (CNS), notably through neuronal networks, located in the hypothalamus and the dorsal vagal complex (DVC), which integrate nutritional, humoral and nervous information from the periphery. The glial cells’ contribution to these processes emerged few year ago. However, its underlying mechanism remains unclear. Glial connexin 43 hemichannels (Cx43 HCs) enable direct exchange with the extracellular space and can regulate neuronal network activity. In the present study, we sought to determine the possible involvement of glial Cx43 HCs in energy balance regulation. We here show that Cx43 is strongly expressed in the hypothalamus and DVC and is associated with glial cells. Remarkably, we observed a close apposition of Cx43 with synaptic elements in both the hypothalamus and DVC. Moreover, the expression of hypothalamic Cx43 mRNA and protein is modulated in response to fasting and diet-induced obesity. Functionally, we found that Cx43 HCs are largely open in the arcuate nucleus (ARC) from acute mice hypothalamic slices under basal condition, and significantly inhibited by TAT-GAP19, a mimetic peptide that specifically blocks Cx43 HCs activity. Moreover, intracerebroventricular (i.c.v.) TAT-GAP19 injection strongly decreased food intake, without further alteration of glycaemia, energy expenditures or locomotor activity. Using the immediate early gene c-Fos expression, we found that i.c.v. TAT-GAP19 injection induced neuronal activation in hypothalamic and brainstem nuclei dedicated to food intake regulation. Altogether, these results suggest a tonic delivery of orexigenic molecules associated with glial Cx43 HCs activity and a possible modulation of this tonus during fasting and obesity.
Collapse
|
22
|
Trujillo-Estrada L, Gomez-Arboledas A, Forner S, Martini AC, Gutierrez A, Baglietto-Vargas D, LaFerla FM. Astrocytes: From the Physiology to the Disease. Curr Alzheimer Res 2020; 16:675-698. [PMID: 31470787 DOI: 10.2174/1567205016666190830110152] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 04/12/2019] [Accepted: 05/17/2019] [Indexed: 12/14/2022]
Abstract
Astrocytes are key cells for adequate brain formation and regulation of cerebral blood flow as well as for the maintenance of neuronal metabolism, neurotransmitter synthesis and exocytosis, and synaptic transmission. Many of these functions are intrinsically related to neurodegeneration, allowing refocusing on the role of astrocytes in physiological and neurodegenerative states. Indeed, emerging evidence in the field indicates that abnormalities in the astrocytic function are involved in the pathogenesis of multiple neurodegenerative diseases, including Alzheimer's Disease (AD), Parkinson's Disease (PD), Huntington's Disease (HD) and Amyotrophic Lateral Sclerosis (ALS). In the present review, we highlight the physiological role of astrocytes in the CNS, including their communication with other cells in the brain. Furthermore, we discuss exciting findings and novel experimental approaches that elucidate the role of astrocytes in multiple neurological disorders.
Collapse
Affiliation(s)
- Laura Trujillo-Estrada
- Institute for Memory Impairments and Neurological Disorders (UCI MIND), University of California, Irvine, CA 92697-4545, United States
| | - Angela Gomez-Arboledas
- Department of Cell Biology, Genetic and Physiology, Faculty of Sciences, University of Malaga, Malaga, Spain.,Instituto de Investigación Biomédica de Malaga-IBIMA, Malaga, Spain.,Networking Research Center on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - Stefânia Forner
- Institute for Memory Impairments and Neurological Disorders (UCI MIND), University of California, Irvine, CA 92697-4545, United States
| | - Alessandra Cadete Martini
- Institute for Memory Impairments and Neurological Disorders (UCI MIND), University of California, Irvine, CA 92697-4545, United States
| | - Antonia Gutierrez
- Department of Cell Biology, Genetic and Physiology, Faculty of Sciences, University of Malaga, Malaga, Spain.,Instituto de Investigación Biomédica de Malaga-IBIMA, Malaga, Spain.,Networking Research Center on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - David Baglietto-Vargas
- Institute for Memory Impairments and Neurological Disorders (UCI MIND), University of California, Irvine, CA 92697-4545, United States.,Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, United States
| | - Frank M LaFerla
- Institute for Memory Impairments and Neurological Disorders (UCI MIND), University of California, Irvine, CA 92697-4545, United States.,Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, United States
| |
Collapse
|
23
|
Glial ATP and Large Pore Channels Modulate Synaptic Strength in Response to Chronic Inactivity. Mol Neurobiol 2020; 57:2856-2869. [PMID: 32388797 DOI: 10.1007/s12035-020-01919-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 04/14/2020] [Indexed: 01/08/2023]
Abstract
A key feature of neurotransmission is its ability to adapt to changes in neuronal environment, which is essential for many brain functions. Homeostatic synaptic plasticity (HSP) emerges as a compensatory mechanism used by neurons to adjust their excitability in response to changes in synaptic activity. Recently, glial cells emerged as modulators for neurotransmission by releasing gliotransmitters into the synaptic cleft through pathways that include P2X7 receptors (P2X7R), connexons, and pannexons. However, the role of gliotransmission in the activity-dependent adjustment of presynaptic strength is still an open question. Here, we investigated whether glial cells participate in HSP upon chronic inactivity and the role of adenosine triphosphate (ATP), connexin43 hemichannels (Cx43HCs), and pannexin1 (Panx1) channels in this process. We used immunocytochemistry against vesicular glutamate transporter 1 (vGlut1) to estimate changes in synaptic strength in hippocampal dissociated cultures. Pharmacological manipulations indicate that glial-derived ATP and P2X7R are required for HSP. In addition, inhibition of Cx43 and Panx1 channels reveals a pivotal role for these channels in the compensatory adjustment of synaptic strength, emerging as new pathways for ATP release upon inactivity. The involvement of Panx1 channels was confirmed by using Panx1-deficient animals. Lacking Panx1 in neurons is sufficient to prevent the P2X7R-dependent upregulation of presynaptic strength; however, the P2X7R-dependent compensatory adjustment of synapse density requires both neuronal and glial Panx1. Together, our data supports an essential role for glial ATP signaling and Cx43HCs and Panx1 channels in the homeostatic adjustment of synaptic strength in hippocampal cultures upon chronic inactivity.
Collapse
|
24
|
Zancan M, Malysz T, Moura DJ, Morás AM, Steffens L, Rasia-Filho AA. Gap junctions and expression of Cx36, Cx43 and Cx45 in the posterodorsal medial amygdala of adult rats. Histol Histopathol 2020; 35:395-403. [PMID: 31495909 DOI: 10.14670/hh-18-160] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The posterodorsal medial amygdala (MePD) has an adapted synaptic organization that dynamically modulates reproduction and other social behaviors in rats. Discrete gap junctions between glial cells were previously reported in the MePD neuropil. Connexins (Cx) are components of gap junctions and indicative of cellular electrical coupling. Here, we report the ultrastructural occurrence of gap junctions between neurons in the MePD and demonstrate the expression and immunofluorescent labeling of Cx36, Cx43 and Cx45 in this subcortical area of adult male rats. Few neuronal gap junctions were found in the MePD and, when identified, occurred between dendrites. On the other hand, there is a diffuse presence and distribution of punctate labelling for the tested Cxs. Puncta were visualized isolated or forming clusters in the same focal plane of cell bodies or along the MePD neuropil. The Cx36 puncta were found in neurons, Cx43 in astrocytes and Cx45 in both neurons and astrocytes. Our data indicate the presence of few gap junctions and different Cxs composition in the MePD. Because Cxs can assemble, form hemichannel units and/or serve as transcriptional regulator, it is likely that additional modulation of intercellular communication can occur besides the chemical transmission in the MePD of adult rats.
Collapse
Affiliation(s)
- Mariana Zancan
- Universidade Federal de Ciências da Saúde de Porto Alegre/DCBS-Physiology, Porto Alegre-RS, Brazil
| | - Taís Malysz
- Universidade Federal do Rio Grande do Sul/ICBS-Anatomy, Porto Alegre-RS, Brazil
- Universidade Federal do Rio Grande do Sul/Graduate Program in Neurosciences, Porto Alegre-RS, Brazil
| | - Dinara J Moura
- Universidade Federal de Ciências da Saúde de Porto Alegre/Graduate Program in Biosciences, Porto Alegre-RS, Brazil
| | - Ana Moira Morás
- Universidade Federal de Ciências da Saúde de Porto Alegre/Graduate Program in Biosciences, Porto Alegre-RS, Brazil
| | - Luiza Steffens
- Universidade Federal de Ciências da Saúde de Porto Alegre/Graduate Program in Biosciences, Porto Alegre-RS, Brazil
| | - Alberto A Rasia-Filho
- Universidade Federal do Rio Grande do Sul/Graduate Program in Neurosciences, Porto Alegre-RS, Brazil
- Universidade Federal de Ciências da Saúde de Porto Alegre/Graduate Program in Biosciences, Porto Alegre-RS, Brazil
- Universidade Federal de Ciências da Saúde de Porto Alegre/DCBS-Physiology, Porto Alegre-RS, Brazil.
| |
Collapse
|
25
|
The Therapeutic Potential of Mesenchymal Stem Cell-Derived Exosomes in Treatment of Neurodegenerative Diseases. Mol Neurobiol 2019; 56:8157-8167. [PMID: 31197655 DOI: 10.1007/s12035-019-01663-0] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 05/27/2019] [Indexed: 12/13/2022]
Abstract
Neurologic complications are commonly regarded as irreversible impairments that stem from limited potential of regeneration of the central nervous system (CNS). On the other side, the regenerative potential of stem cells has been evaluated in basic research, as well as in preclinical studies. Mesenchymal stem cells (MSCs) have been regarded as candidate cell sources for therapeutic purposes of various neurological disorders, because of their self-renewal ability, plasticity in differentiation, neurotrophic characteristics, and immunomodulatory properties. Exosomes are extracellular vesicles which can deliver biological information over long distances and thereby influencing normal and abnormal processes in cells and tissues. The therapeutic capacity of exosomes relies on the type of cell, as well as on the physiological condition of a given cell. Therefore, based on tissue type and physiological condition of CNS, exosomes may function as contributors or suppressors of pathological conditions in this tissue. When it comes to the therapeutic viewpoint, the most promising cellular source of exosomes is considered to be MSCs. The aim of this review article is to discuss the current knowledge around the potential of stem cells and MSC-derived exosomes in the treatment of neurodegenerative diseases.
Collapse
|
26
|
Ali AAH, Stahr A, Ingenwerth M, Theis M, Steinhäuser C, von Gall C. Connexin30 and Connexin43 show a time-of-day dependent expression in the mouse suprachiasmatic nucleus and modulate rhythmic locomotor activity in the context of chronodisruption. Cell Commun Signal 2019; 17:61. [PMID: 31186021 PMCID: PMC6560876 DOI: 10.1186/s12964-019-0370-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 05/14/2019] [Indexed: 11/15/2022] Open
Abstract
Background The astroglial connexins Cx30 and Cx43 contribute to many important CNS functions including cognitive behaviour, motoric capacity and regulation of the sleep-wake cycle. The sleep wake cycle, is controlled by the circadian system. The central circadian rhythm generator resides in the suprachiasmatic nucleus (SCN). SCN neurons are tightly coupled in order to generate a coherent circadian rhythm. The SCN receives excitatory glutamatergic input from the retina which mediates entrainment of the circadian system to the environmental light-dark cycle. Connexins play an important role in electric coupling of SCN neurons and astrocytic-neuronal signalling that regulates rhythmic SCN neuronal activity. However, little is known about the regulation of Cx30 and Cx43 expression in the SCN, and the role of these connexins in light entrainment of the circadian system and in circadian rhythm generation. Methods We analysed time-of-day dependent as well as circadian expression of Cx30 and Cx43 mRNA and protein in the mouse SCN by means of qPCR and immunohistochemistry. Moreover, we analysed rhythmic spontaneous locomotor activity in mice with a targeted deletion of Cx30 and astrocyte specific deletion of Cx43 (DKO) in different light regimes by means of on-cage infrared detectors. Results Fluctuation of Cx30 protein expression is strongly dependent on the light-dark cycle whereas fluctuation of Cx43 protein expression persisted in constant darkness. DKO mice entrained to the light-dark cycle. However, re-entrainment after a phase delay was slightly impaired in DKO mice. Surprisingly, DKO mice were more resilient to chronodisruption. Conclusion Circadian fluctuation of Cx30 and Cx43 protein expression in the SCN is differently regulated. Cx30 and astroglial Cx43 play a role in rhythm stability and re-entrainment under challenging conditions. Electronic supplementary material The online version of this article (10.1186/s12964-019-0370-2) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Amira A H Ali
- Institute of Anatomy II, Medical Faculty, Heinrich-Heine-University, Merowinger Platz 1A, 40225, Düsseldorf, Germany
| | - Anna Stahr
- Institute of Anatomy II, Medical Faculty, Heinrich-Heine-University, Merowinger Platz 1A, 40225, Düsseldorf, Germany
| | - Marc Ingenwerth
- Institute of Pathology, Medical Faculty, University of Duisburg-Essen, Hufelandstrasse 55, 45147, Essen, Germany
| | - Martin Theis
- Institute of Cellular Neurosciences, Medical Faculty, University Bonn, Sigmund Freud Str. 25, 53105, Bonn, Germany
| | - Christian Steinhäuser
- Institute of Cellular Neurosciences, Medical Faculty, University Bonn, Sigmund Freud Str. 25, 53105, Bonn, Germany
| | - Charlotte von Gall
- Institute of Anatomy II, Medical Faculty, Heinrich-Heine-University, Merowinger Platz 1A, 40225, Düsseldorf, Germany.
| |
Collapse
|
27
|
Cui GH, Guo HD, Li H, Zhai Y, Gong ZB, Wu J, Liu JS, Dong YR, Hou SX, Liu JR. RVG-modified exosomes derived from mesenchymal stem cells rescue memory deficits by regulating inflammatory responses in a mouse model of Alzheimer's disease. IMMUNITY & AGEING 2019; 16:10. [PMID: 31114624 PMCID: PMC6515654 DOI: 10.1186/s12979-019-0150-2] [Citation(s) in RCA: 150] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 04/26/2019] [Indexed: 12/23/2022]
Abstract
Background Exosomes are lipid-bilayer enclosed nano-sized vesicles that transfer functional cellular proteins, mRNA and miRNAs. Mesenchymal stem cells (MSCs) derived exosomes have been demonstrated to prevent memory deficits in the animal model of Alzheimer’s disease (AD). However, the intravenously injected exosomes could be abundantly tracked in other organs except for the targeted regions in the brain. Here, we proposed the use of central nervous system-specific rabies viral glycoprotein (RVG) peptide to target intravenously-infused exosomes derived from MSCs (MSC-Exo) to the brain of transgenic APP/PS1 mice. MSC-Exo were conjugated with RVG through a DOPE-NHS linker. Results RVG-tagged MSC-Exo exhibited improved targeting to the cortex and hippocampus after being administered intravenously. Compared with the group administered MSC-Exo, in the group administered RVG-conjugated MSC-Exo (MSC-RVG-Exo) plaque deposition and Aβ levels were sharply decreased and activation of astrocytes was obviously reduced. The brain targeted exosomes derived from MSCs was better than unmodified exosomes to improve cognitive function in APP/PS1 mice according to Morris water maze test. Additionally, although MSC-Exo injected intravenously reduced the expression of pro-inflammatory mediators TNF-α, IL-β, and IL-6, but the changes of anti-inflammatory factors IL-10 and IL-13 were not obvious. However, administration of MSC-RVG-Exo significantly reduced the levels of TNF-α, IL-β, and IL-6 while significantly raised the levels of IL-10, IL-4 and IL-13. Conclusions Taken together, our results demonstrated a novel method for increasing delivery of exosomes for treatment of AD. By targeting exosomes to the cortex and hippocampus of AD mouse, there was a significant improvement in learning and memory capabilities with reduced plaque deposition and Aβ levels, and normalized levels of inflammatory cytokines. Electronic supplementary material The online version of this article (10.1186/s12979-019-0150-2) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Guo-Hong Cui
- 1Department of Neurology, Shanghai No. 9 People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200011 China
| | - Hai-Dong Guo
- 2Department of Anatomy, School of Basic Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203 China
| | - Han Li
- 2Department of Anatomy, School of Basic Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203 China
| | - Yu Zhai
- 1Department of Neurology, Shanghai No. 9 People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200011 China
| | - Zhang-Bin Gong
- 3Department of Biochemistry, School of Basic Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203 China
| | - Jing Wu
- 1Department of Neurology, Shanghai No. 9 People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200011 China
| | - Jian-Sheng Liu
- 1Department of Neurology, Shanghai No. 9 People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200011 China
| | - You-Rong Dong
- 1Department of Neurology, Shanghai No. 9 People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200011 China
| | - Shuang-Xing Hou
- 4Department of Neurology, Shanghai Pudong Hospital, Fudan University Pudong Medical Center, Shanghai, 201399 China
| | - Jian-Ren Liu
- 1Department of Neurology, Shanghai No. 9 People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200011 China
| |
Collapse
|
28
|
Pannasch U, Dossi E, Ezan P, Rouach N. Astroglial Cx30 sustains neuronal population bursts independently of gap-junction mediated biochemical coupling. Glia 2019; 67:1104-1112. [PMID: 30794327 PMCID: PMC6519011 DOI: 10.1002/glia.23591] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 12/21/2018] [Accepted: 12/28/2018] [Indexed: 11/06/2022]
Abstract
Astroglial networks mediated by gap junction channels contribute to neurotransmission and promote neuronal coordination. Connexin 30, one of the two main astroglial gap junction forming protein, alters at the behavioral level the reactivity of mice to novel environment and at the synaptic level excitatory transmission. However, the role and function of Cx30 at the neuronal network level remain unclear. We thus investigated whether Cx30 regulates neuronal population bursts and associated convulsive behavior. We found in vivo that Cx30 is upregulated by kainate-induced seizures and that it regulates in turn the severity of associated behavioral seizures. Using electrophysiology ex vivo, we report that Cx30 regulates aberrant network activity via control of astroglial glutamate clearance independently of gap-junction mediated biochemical coupling. Altogether, our results indicate that astroglial Cx30 is an important player in orchestrating neuronal network activity.
Collapse
Affiliation(s)
- Ulrike Pannasch
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, Centre National de la Recherche Scientifique UMR 7241, Institut National de la Santé et de la Recherche Médicale U1050, Labex Memolife, PSL Research University, Paris, France
| | - Elena Dossi
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, Centre National de la Recherche Scientifique UMR 7241, Institut National de la Santé et de la Recherche Médicale U1050, Labex Memolife, PSL Research University, Paris, France
| | - Pascal Ezan
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, Centre National de la Recherche Scientifique UMR 7241, Institut National de la Santé et de la Recherche Médicale U1050, Labex Memolife, PSL Research University, Paris, France
| | - Nathalie Rouach
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, Centre National de la Recherche Scientifique UMR 7241, Institut National de la Santé et de la Recherche Médicale U1050, Labex Memolife, PSL Research University, Paris, France
| |
Collapse
|
29
|
Specific deletion connexin43 in astrocyte ameliorates cognitive dysfunction in APP/PS1 mice. Life Sci 2018; 208:175-191. [PMID: 30031059 DOI: 10.1016/j.lfs.2018.07.033] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 07/15/2018] [Accepted: 07/18/2018] [Indexed: 11/22/2022]
Abstract
Emerging data indicate an important role for connexin43 (Cx43) in cognitive function, but there is a lack of direct evidence of the role of astroglial Cx43 in cognitive dysfunction in Alzheimer's disease (AD). Here we evaluated the expression pattern of Cx43 in AD and found progressive upregulation of the mRNA and protein levels of Cx43. Subsequently, we generated an astroglial Cx43 knockout (KO) AD mouse model by crossbreeding Gfap (glial fibrillary acidic protein)-Cx43 KO mice with APP/PS1 mice. Then we assessed the cognitive function of 12-month-old APP (amyloid precursor protein)/PS1 (presenilin 1)/Gfap-Cx43 KO mice, which demonstrated that the deletion of astroglial Cx43 significantly ameliorated cognitive dysfunction. To further investigate the underlying mechanisms, we evaluated amyloid plaque formation, astrogliosis, and synaptic function. The number and area of amyloid plaques were not altered, but GFAP expression was significantly decreased and the number of synapses was markedly upregulated. These results suggest that deletion of astroglial Cx43 in APP/PS1 mice did not affect the formation of amyloid plaques but depressed astrogliosis and upregulated synaptic function. Moreover, levels of critical modulators of astroglial activation were also notably reduced, but those of pro- and anti-inflammatory cytokines were not altered. Furthermore, Cx43 regulation of postsynaptic elements targets mainly NMDAR (N-methyl-d-aspartate). In addition, the prevention of AD pathology was reversed by Cx43 re-expression. In sum, specific deletion of astroglial Cx43 in APP/PS1 mice improved cognitive dysfunction by decreasing astrogliosis and increasing synaptic function without affecting amyloid plaque formation or the inflammatory response.
Collapse
|
30
|
Xin W, Bonci A. Functional Astrocyte Heterogeneity and Implications for Their Role in Shaping Neurotransmission. Front Cell Neurosci 2018; 12:141. [PMID: 29896091 PMCID: PMC5987431 DOI: 10.3389/fncel.2018.00141] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 05/08/2018] [Indexed: 12/20/2022] Open
Abstract
In recent years, the role of astrocytes in shaping neuronal signaling has come to the forefront of neuroscience research. The development of genetic tools that enable targeted manipulation of astrocytes has revealed a wealth of mechanisms by which they can alter the synaptic strength and intrinsic excitability of neurons in behaviorally relevant ways. In parallel, several studies have demonstrated significant variability in the gene expression and physiology of astrocytes within and between brain regions. Thus, to form an accurate understanding of how astrocytes contribute to neuronal transmission, we must take into consideration the diversity that exists in their intrinsic properties. In this review, we will summarize recent findings on astrocyte heterogeneity and discuss the implications for their interactions with neurons and their effects on neuronal transmission.
Collapse
Affiliation(s)
- Wendy Xin
- Synaptic Plasticity Section, Cellular Neurobiology Branch, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD, United States.,Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Antonello Bonci
- Synaptic Plasticity Section, Cellular Neurobiology Branch, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD, United States.,Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States.,Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, United States.,Department of Neuroscience, Georgetown University Medical Center, School of Medicine, Washington, DC, United States.,Department of Psychiatry, University of Maryland, School of Medicine, Baltimore, MD, United States
| |
Collapse
|
31
|
Walrave L, Pierre A, Albertini G, Aourz N, De Bundel D, Van Eeckhaut A, Vinken M, Giaume C, Leybaert L, Smolders I. Inhibition of astroglial connexin43 hemichannels with TAT-Gap19 exerts anticonvulsant effects in rodents. Glia 2018; 66:1788-1804. [PMID: 29683209 DOI: 10.1002/glia.23341] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 04/04/2018] [Accepted: 04/04/2018] [Indexed: 12/14/2022]
Abstract
Accumulating evidence shows a key function for astrocytic connexin43 (Cx43) signaling in epilepsy. However, the lack of experimental distinction between Cx43 gap junction channels (GJCs) and hemichannels (HCs) has impeded the identification of the exact contribution of either channel configurations to epilepsy. We therefore investigated whether TAT-Gap19, a Cx mimetic peptide that inhibits Cx43 HCs but not the corresponding Cx43 GJCs, influences experimentally induced seizures in rodents. Dye uptake experiments in acute hippocampal slices of mice demonstrated that astroglial Cx43 HCs open in response to the chemoconvulsant pilocarpine and this was inhibited by TAT-Gap19. In vivo, pilocarpine-induced seizures as well as the accompanying increase in D-serine microdialysate levels were suppressed by Cx43 HC inhibition. Moreover, the anticonvulsant action of TAT-Gap19 was reversed by exogenous D-serine administration, suggesting that Cx43 HC inhibition protects against seizures by lowering extracellular D-serine levels. The anticonvulsive properties of Cx43 HC inhibition were further confirmed in electrical seizure mouse models, i.e. an acute 6 Hertz (Hz) model of refractory seizures and a chronic 6 Hz corneal kindling model. Collectively, these results indicate that Cx43 HCs play a role in seizures and underscore their potential as a novel and druggable target in epilepsy treatment.
Collapse
Affiliation(s)
- Laura Walrave
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| | - Anouk Pierre
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| | - Giulia Albertini
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| | - Najat Aourz
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| | - Dimitri De Bundel
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| | - Ann Van Eeckhaut
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| | - Christian Giaume
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, Paris, 75005, France
| | - Luc Leybaert
- Physiology group, Department of Basic Medical Sciences, Ghent University, De Pintelaan 185, Ghent, 9000, Belgium
| | - Ilse Smolders
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| |
Collapse
|
32
|
Mayorquin LC, Rodriguez AV, Sutachan JJ, Albarracín SL. Connexin-Mediated Functional and Metabolic Coupling Between Astrocytes and Neurons. Front Mol Neurosci 2018; 11:118. [PMID: 29695954 PMCID: PMC5905222 DOI: 10.3389/fnmol.2018.00118] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 03/27/2018] [Indexed: 01/24/2023] Open
Abstract
The central nervous system (CNS) requires sophisticated regulation of neuronal activity. This modulation is partly accomplished by non-neuronal cells, characterized by the presence of transmembrane gap junctions (GJs) and hemichannels (HCs). This allows small molecule diffusion to guarantee neuronal synaptic activity and plasticity. Astrocytes are metabolically and functionally coupled to neurons by the uptake, binding and recycling of neurotransmitters. In addition, astrocytes release metabolites, such as glutamate, glutamine, D-serine, adenosine triphosphate (ATP) and lactate, regulating synaptic activity and plasticity by pre- and postsynaptic mechanisms. Uncoupling neuroglial communication leads to alterations in synaptic transmission that can be detrimental to neuronal circuit function and behavior. Therefore, understanding the pathways and mechanisms involved in this intercellular communication is fundamental for the search of new targets that can be used for several neurological disease treatments. This review will focus on molecular mechanisms mediating physiological and pathological coupling between astrocytes and neurons through GJs and HCs.
Collapse
Affiliation(s)
- Lady C Mayorquin
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Andrea V Rodriguez
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Jhon-Jairo Sutachan
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Sonia L Albarracín
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá, Colombia
| |
Collapse
|
33
|
Abstract
Major depressive disorder (MDD) is a chronic and debilitating illness that affects over 350 million people worldwide; however, current treatments have failed to cure or prevent the progress of depression. Increasing evidence suggests a crucial role for connexins in MDD. In this review, we have summarised recent accomplishments regarding the role of connexins, gap junctions, and hemichannels in the aetiology of MDD, and discussed the limitations of current research. A blockage of gap junctions or hemichannels induces depressive behaviour. Possible underlying mechanisms include the regulation of neurosecretory functions and synaptic activity by gap junctions and hemichannels. Gap junctions are functionally inhibited under stress conditions. Conversely, hemichannel permeability is increased. Antidepressants inhibit hemichannel permeability; however, they have contrasting effects on the function of gap junctions under normal conditions and can protect them against stress. In conclusion, the blockage of hemichannels concurrent with improvements in gap junction functionality might be potential targets for depression treatment.
Collapse
Affiliation(s)
- Cong-Yuan Xia
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Zhen-Zhen Wang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Tohru Yamakuni
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai 980-8578, Japan
| | - Nai-Hong Chen
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China; College of Pharmacy, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China.
| |
Collapse
|
34
|
Hillen AEJ, Burbach JPH, Hol EM. Cell adhesion and matricellular support by astrocytes of the tripartite synapse. Prog Neurobiol 2018; 165-167:66-86. [PMID: 29444459 DOI: 10.1016/j.pneurobio.2018.02.002] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 07/25/2017] [Accepted: 02/07/2018] [Indexed: 12/18/2022]
Abstract
Astrocytes contribute to the formation, function, and plasticity of synapses. Their processes enwrap the neuronal components of the tripartite synapse, and due to this close interaction they are perfectly positioned to modulate neuronal communication. The interaction between astrocytes and synapses is facilitated by cell adhesion molecules and matricellular proteins, which have been implicated in the formation and functioning of tripartite synapses. The importance of such neuron-astrocyte integration at the synapse is underscored by the emerging role of astrocyte dysfunction in synaptic pathologies such as autism and schizophrenia. Here we review astrocyte-expressed cell adhesion molecules and matricellular molecules that play a role in integration of neurons and astrocytes within the tripartite synapse.
Collapse
Affiliation(s)
- Anne E J Hillen
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, 3584 CG Utrecht, The Netherlands; Department of Pediatrics/Child Neurology, VU University Medical Center, 1081 HV Amsterdam, The Netherlands
| | - J Peter H Burbach
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, 3584 CG Utrecht, The Netherlands
| | - Elly M Hol
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, 3584 CG Utrecht, The Netherlands; Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, 1098 XH Amsterdam, The Netherlands; Department of Neuroimmunology, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences, 1105 BA Amsterdam, The Netherlands.
| |
Collapse
|
35
|
Cui GH, Wu J, Mou FF, Xie WH, Wang FB, Wang QL, Fang J, Xu YW, Dong YR, Liu JR, Guo HD. Exosomes derived from hypoxia-preconditioned mesenchymal stromal cells ameliorate cognitive decline by rescuing synaptic dysfunction and regulating inflammatory responses in APP/PS1 mice. FASEB J 2018; 32:654-668. [PMID: 28970251 DOI: 10.1096/fj.201700600r] [Citation(s) in RCA: 229] [Impact Index Per Article: 38.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Administration of exosomes derived from mesenchymal stromal cells (MSCs) could improve some neurologic conditions by transferring functional biomolecules to recipient cells. Furthermore, exosomes from hypoxic progenitor cells exerted better therapeutic effects in organ injury through specific cargoes. However, there are no related reports about whether exosomes derived from MSCs or hypoxia-preconditioned MSCs (PC-MSCs) could prevent memory deficits in Alzheimer disease (AD). In this study, the exosomes derived from MSCs or PC-MSCs were systemically administered to transgenic APP/PS1 mice. The expression of miR-21 in MSCs was significantly increased after hypoxic treatment. Injection of exosomes from normoxic MSCs could rescue cognition and memory impairment according to results of the Morris water maze test, reduced plaque deposition, and Aβ levels in the brain; could decrease the activation of astrocytes and microglia; could down-regulate proinflammatory cytokines (TNF-α and IL-1β); and could up-regulate anti-inflammatory cytokines (IL-4 and -10) in AD mice, as well as reduce the activation of signal transducer and activator of transcription 3 (STAT3) and NF-κB. Compared to the group administered exosomes from normoxic MSCs, in the group administered exosomes from PC-MSCs, learning and memory capabilities were significantly improved; the plaque deposition and Aβ levels were lower, and expression of growth-associated protein 43, synapsin 1, and IL-10 was increased; and the levels of glial fibrillary acidic protein, ionized calcium-binding adaptor molecule 1, TNF-α, IL-1β, and activation of STAT3 and NF-κB were sharply decreased. More importantly, exosomes from PC-MSCs effectively increased the level of miR-21 in the brain of AD mice. Additionally, replenishment of miR-21 restored the cognitive deficits in APP/PS1 mice and prevented pathologic features. Taken together, these findings suggest that exosomes from PC-MSCs could improve the learning and memory capabilities of APP/PS1 mice, and that the underlying mechanism may lie in the restoration of synaptic dysfunction and regulation of inflammatory responses through regulation of miR-21.-Cui, G.-H., Wu, J., Mou, F.-F., Xie, W.-H., Wang, F.-B., Wang, Q.-L., Fang, J., Xu, Y.-W., Dong, Y.-R., Liu, J.-R., Guo, H.-D. Exosomes derived from hypoxia-preconditioned mesenchymal stromal cells ameliorate cognitive decline by rescuing synaptic dysfunction and regulating inflammatory responses in APP/PS1 mice.
Collapse
Affiliation(s)
- Guo-Hong Cui
- Department of Neurology, Shanghai No. 9 People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Jing Wu
- Department of Neurology, Shanghai No. 9 People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Fang-Fang Mou
- Department of Anatomy, School of Basic Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Wei-Hua Xie
- Department of Constipation, Acupuncture, and Moxibustion, Hospital of Anhui Province, Hefei, China
| | - Fu-Bo Wang
- Department of Anatomy, School of Basic Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Qiang-Li Wang
- Department of Anatomy, School of Basic Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Jie Fang
- Department of Neurology, Shanghai No. 9 People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yan-Wu Xu
- Department of Anatomy, School of Basic Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - You-Rong Dong
- Department of Neurology, Shanghai No. 9 People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Jian-Ren Liu
- Department of Neurology, Shanghai No. 9 People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Hai-Dong Guo
- Department of Anatomy, School of Basic Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| |
Collapse
|
36
|
Malik S, Theis M, Eugenin EA. Connexin43 Containing Gap Junction Channels Facilitate HIV Bystander Toxicity: Implications in NeuroHIV. Front Mol Neurosci 2017; 10:404. [PMID: 29259541 PMCID: PMC5723329 DOI: 10.3389/fnmol.2017.00404] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 11/21/2017] [Indexed: 02/02/2023] Open
Abstract
Human immunodeficiency virus-1 (HIV-1) infection compromises the central nervous system (CNS) in a significant number of infected individuals, resulting in neurological dysfunction that ranges from minor cognitive deficits to frank dementia. While macrophages/microglia are the predominant CNS cells infected by HIV, our laboratory and others have shown that HIV-infected astrocytes, although present in relatively low numbers with minimal to undetectable viral replication, play key role in NeuroAIDS pathogenesis. Our laboratory has identified that HIV "hijacks" connexin (Cx) containing channels, such as gap junctions (GJs) and hemichannels (HCs), to spread toxicity and apoptosis to uninfected cells even in the absence of active viral replication. In this study, using a murine model with an astrocyte-directed deletion of Cx43 gene (hGFAP-cre Cx43fl/fl) and control Cx43fl/fl mice, we examined whether few HIV-infected human astrocytoma cells (U87-CD4-CCR5), microinjected into the mouse cortex, can spread toxicity and apoptosis through GJ-mediated mechanisms, into the mouse cells, which are resistant to HIV infection. In the control Cx43fl/fl mice, microinjection of HIV-infected U87-CD4-CCR5 cells led to apoptosis in 84.28 ± 6.38% of mouse brain cells around the site of microinjection, whereas hGFAP-cre Cx43fl/fl mice exhibited minimal apoptosis (2.78 ± 1.55%). However, simultaneous injection of GJ blocker, 18α-glycyrrhetinic acid, and Cx43 blocking peptide along with microinjection of HIV-infected cells prevented apoptosis in Cx43fl/fl mice, demonstrating the Cx43 is essential for HIV-induced bystander toxicity. In conclusion, our findings demonstrate that Cx43 expression, and formation of GJs is essential for bystander apoptosis during HIV infection. These findings reveal novel potential therapeutic targets to reduce astrocyte-mediated bystander toxicity in HIV-infected individuals because despite low to undetectable viral replication in the CNS, Cx channels hijacked by HIV amplify viral neuropathogenesis.
Collapse
Affiliation(s)
- Shaily Malik
- Public Health Research Institute (PHRI), Newark, NJ, United States.,Department of Microbiology, Biochemistry, and Molecular Genetics, Rutgers New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, United States
| | - Martin Theis
- Institute of Cellular Neurosciences, University of Bonn, Bonn, Germany
| | - Eliseo A Eugenin
- Public Health Research Institute (PHRI), Newark, NJ, United States.,Department of Microbiology, Biochemistry, and Molecular Genetics, Rutgers New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, United States
| |
Collapse
|
37
|
Heterogeneity and function of hippocampal macroglia. Cell Tissue Res 2017; 373:653-670. [PMID: 29204745 DOI: 10.1007/s00441-017-2746-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 11/16/2017] [Indexed: 12/26/2022]
Abstract
The contribution of glial cells to normal and impaired hippocampal function is increasingly being recognized, although important questions as to the mechanisms that these cells use for their crosstalk with neurons and capillaries are still unanswered or lead to controversy. Astrocytes in the hippocampus are morphologically variable and a single cell contacts with its processes more than 100,000 synapses. They predominantly express inward rectifier K+ channels and transporters serving homeostatic function but may also release gliotransmitters to modify neuronal signaling and brain circulation. Intracellular Ca2+ transients are key events in the interaction of astrocytes with neurons and the vasculature. Hippocampal NG2 glia represent a population of cells with proliferative capacity throughout adulthood. Intriguingly, they receive direct synaptic input from pyramidal neurons and interneurons and express a multitude of ion channels and receptors. Despite in-depth knowledge about the features of these transmembrane proteins, the physiological impact of NG2 glial cells and their synaptic input remain nebulous. Because of the low abundance of oligodendrocytes in the hippocampus, limited information is available about their specific properties. Given the multitude of signaling molecules expressed by the various types of hippocampal glial cells (and because of space constraints), we focus, in this review, on those properties that are considered key for the interaction of the respective cell type with its neighborhood.
Collapse
|
38
|
Dong H, Zhou XW, Wang X, Yang Y, Luo JW, Liu YH, Mao Q. Complex role of connexin 43 in astrocytic tumors and possible promotion of glioma‑associated epileptic discharge (Review). Mol Med Rep 2017; 16:7890-7900. [PMID: 28983585 DOI: 10.3892/mmr.2017.7618] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 06/19/2017] [Indexed: 02/05/2023] Open
Abstract
Connexin (Cx)43 is a multifunction protein which forms gap junction channels and hemi‑channels. It also contains abundant binding domains which possess the ability to interact with certain Cx43‑associated proteins and therefore serve a fundamental role in various physiological and pathological functions. However, the understanding of the association between cancer and Cx43 along with Cx43‑gap junctions (GJ) remains unclear. All available data illustrate that Cx43 and its associated GJ serve important functions in cancers. The expression levels of Cx43 demonstrate a downward trend and an increase in the levels of malignancy, particularly in astrocytomas. The GJ intercellular communication activity in glioma cells can be adjusted via Cx43 phosphorylation and through the combination of Cx43 and its associated protein. Available evidence reveals Cx43 as a tumor‑inhibiting factor that suppresses glioma growth and proliferation. However, its mechanism is also regarded as complicated and ambiguous. Furthermore, it is apparent that Cx43‑GJ and the carboxyl tail may contribute to glioma growth and proliferation too. However, this valuable role could be weakened by its effects on migration and invasiveness. The detailed mechanism remains unclear and full of controversies. Cx43 can enhance the motor ability and invasiveness of astrocytic glioma cells. It is also able to influence glioma cells to detach from the tumor core to the peritumoral neocortex. This peritumoral region has recently been regarded as the basic focus of glioma‑associated seizure. Thus, Cx43 may take part in the onset and development of glioma‑associated epileptic discharge. In addition, change and increase of Cx43 expression in GJs has been observed in seizure perilesional tissue, which is associated with brain tumors. Cx43 or GJ/hemi‑channels exert enduring effects in the promotion of glioma‑associated epileptic release through direct mass effects and change of the tumor microenvironment. However, there are still a number of issues concerning this aspect that require further exploration. Cx43, as a potential treatment target against this incurable disease and its common symptom of epilepsy, requires further investigation.
Collapse
Affiliation(s)
- Hui Dong
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Xing-Wang Zhou
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Xiang Wang
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Yuan Yang
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Jie-Wen Luo
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Yan-Hui Liu
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Qing Mao
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| |
Collapse
|
39
|
Abstract
Neuronal survival, electrical signaling and synaptic activity require a well-balanced micro-environment in the central nervous system. This is achieved by the blood-brain barrier (BBB), an endothelial barrier situated in the brain capillaries, that controls near-to-all passage in and out of the brain. The endothelial barrier function is highly dependent on signaling interactions with surrounding glial, neuronal and vascular cells, together forming the neuro-glio-vascular unit. Within this functional unit, connexin (Cx) channels are of utmost importance for intercellular communication between the different cellular compartments. Connexins are best known as the building blocks of gap junction (GJ) channels that enable direct cell-cell transfer of metabolic, biochemical and electric signals. In addition, beyond their role in direct intercellular communication, Cxs also form unapposed, non-junctional hemichannels in the plasma membrane that allow the passage of several paracrine messengers, complementing direct GJ communication. Within the NGVU, Cxs are expressed in vascular endothelial cells, including those that form the BBB, and are eminent in astrocytes, especially at their endfoot processes that wrap around cerebral vessels. However, despite the density of Cx channels at this so-called gliovascular interface, it remains unclear as to how Cx-based signaling between astrocytes and BBB endothelial cells may converge control over BBB permeability in health and disease. In this review we describe available evidence that supports a role for astroglial as well as endothelial Cxs in the regulation of BBB permeability during development as well as in disease states.
Collapse
|
40
|
Lapato AS, Tiwari-Woodruff SK. Connexins and pannexins: At the junction of neuro-glial homeostasis & disease. J Neurosci Res 2017; 96:31-44. [PMID: 28580666 DOI: 10.1002/jnr.24088] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 04/08/2017] [Accepted: 05/01/2017] [Indexed: 12/15/2022]
Abstract
In the central nervous system (CNS), connexin (Cx)s and pannexin (Panx)s are an integral component of homeostatic neuronal excitability and synaptic plasticity. Neuronal Cx gap junctions form electrical synapses across biochemically similar GABAergic networks, allowing rapid and extensive inhibition in response to principle neuron excitation. Glial Cx gap junctions link astrocytes and oligodendrocytes in the pan-glial network that is responsible for removing excitotoxic ions and metabolites. In addition, glial gap junctions help constrain excessive excitatory activity in neurons and facilitate astrocyte Ca2+ slow wave propagation. Panxs do not form gap junctions in vivo, but Panx hemichannels participate in autocrine and paracrine gliotransmission, alongside Cx hemichannels. ATP and other gliotransmitters released by Cx and Panx hemichannels maintain physiologic glutamatergic tone by strengthening synapses and mitigating aberrant high frequency bursting. Under pathological depolarizing and inflammatory conditions, gap junctions and hemichannels become dysregulated, resulting in excessive neuronal firing and seizure. In this review, we present known contributions of Cxs and Panxs to physiologic neuronal excitation and explore how the disruption of gap junctions and hemichannels lead to abnormal glutamatergic transmission, purinergic signaling, and seizures.
Collapse
Affiliation(s)
- Andrew S Lapato
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, 92521.,Center for Glial-Neuronal Interactions, University of California Riverside, Riverside, CA, 92521
| | - Seema K Tiwari-Woodruff
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, 92521.,Center for Glial-Neuronal Interactions, University of California Riverside, Riverside, CA, 92521.,Neuroscience Graduate Program, University of California Riverside, Riverside, CA, 92521
| |
Collapse
|
41
|
Liew LC, Katsuda T, Gailhouste L, Nakagama H, Ochiya T. Mesenchymal stem cell-derived extracellular vesicles: a glimmer of hope in treating Alzheimer’s disease. Int Immunol 2017; 29:11-19. [DOI: 10.1093/intimm/dxx002] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2016] [Accepted: 01/13/2017] [Indexed: 12/18/2022] Open
Affiliation(s)
- Lee Chuen Liew
- Division of Molecular and Cellular Medicine, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
- Department of Pathology, Immunology and Microbiology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyou-ku, Tokyo 113-0033, Japan
| | - Takeshi Katsuda
- Division of Molecular and Cellular Medicine, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Luc Gailhouste
- Division of Molecular and Cellular Medicine, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Hitoshi Nakagama
- Department of Pathology, Immunology and Microbiology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyou-ku, Tokyo 113-0033, Japan
- National Cancer Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Takahiro Ochiya
- Division of Molecular and Cellular Medicine, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| |
Collapse
|
42
|
Walrave L, Vinken M, Albertini G, De Bundel D, Leybaert L, Smolders IJ. Inhibition of Connexin43 Hemichannels Impairs Spatial Short-Term Memory without Affecting Spatial Working Memory. Front Cell Neurosci 2016; 10:288. [PMID: 28066184 PMCID: PMC5168429 DOI: 10.3389/fncel.2016.00288] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 12/02/2016] [Indexed: 12/15/2022] Open
Abstract
Astrocytes are active players in higher brain function as they can release gliotransmitters, which are essential for synaptic plasticity. Various mechanisms have been proposed for gliotransmission, including vesicular mechanisms as well as non-vesicular ones, for example by passive diffusion via connexin hemichannels (HCs). We here investigated whether interfering with connexin43 (Cx43) HCs influenced hippocampal spatial memory. We made use of the peptide Gap19 that blocks HCs but not gap junction channels and is specific for Cx43. To this end, we microinfused transactivator of transcription linked Gap19 (TAT-Gap19) into the brain ventricle of male NMRI mice and assessed spatial memory in a Y maze. We found that the in vivo blockade of Cx43 HCs did not affect the locomotor activity or spatial working memory in a spontaneous alternation Y maze task. Cx43 blockade did however significantly impair the spatial short-term memory in a delayed spontaneous alternation Y maze task. These results indicate that Cx43 HCs play a role in spatial short-term memory.
Collapse
Affiliation(s)
- Laura Walrave
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Center for Neurosciences, Vrije Universiteit Brussel Brussels, Belgium
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel Brussels, Belgium
| | - Giulia Albertini
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Center for Neurosciences, Vrije Universiteit Brussel Brussels, Belgium
| | - Dimitri De Bundel
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Center for Neurosciences, Vrije Universiteit Brussel Brussels, Belgium
| | - Luc Leybaert
- Physiology Group, Department of Basic Medical Sciences, Ghent University Ghent, Belgium
| | - Ilse J Smolders
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Center for Neurosciences, Vrije Universiteit Brussel Brussels, Belgium
| |
Collapse
|
43
|
Adermark L, Bowers MS. Disentangling the Role of Astrocytes in Alcohol Use Disorder. Alcohol Clin Exp Res 2016; 40:1802-16. [PMID: 27476876 PMCID: PMC5407469 DOI: 10.1111/acer.13168] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2016] [Accepted: 07/02/2016] [Indexed: 01/29/2023]
Abstract
Several laboratories recently identified that astrocytes are critical regulators of addiction machinery. It is now known that astrocyte pathology is a common feature of ethanol (EtOH) exposure in both humans and animal models, as even brief EtOH exposure is sufficient to elicit long-lasting perturbations in astrocyte gene expression, activity, and proliferation. Astrocytes were also recently shown to modulate the motivational properties of EtOH and other strongly reinforcing stimuli. Given the role of astrocytes in regulating glutamate homeostasis, a crucial component of alcohol use disorder (AUD), astrocytes might be an important target for the development of next-generation alcoholism treatments. This review will outline some of the more prominent features displayed by astrocytes, how these properties are influenced by acute and long-term EtOH exposure, and future directions that may help to disentangle astrocytic from neuronal functions in the etiology of AUD.
Collapse
Affiliation(s)
- Louise Adermark
- Addiction Biology Unit, Department of Psychiatry and Neurochemistry, Sahlgrenska Academy, University of Gothenburg, Box 410, SE-405 30 Gothenburg, Sweden
| | - M. Scott Bowers
- Department of Psychiatry, Virginia Commonwealth University, PO Box 980126, Richmond, VA 23298, USA
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, PO Box 980126, Richmond, VA 23298, USA
- Faulk Center for Molecular Therapeutics, Northwestern University; Aptinyx,, Evanston, Il 60201, USA
| |
Collapse
|
44
|
Nagy C, Torres-Platas SG, Mechawar N, Turecki G. Repression of Astrocytic Connexins in Cortical and Subcortical Brain Regions and Prefrontal Enrichment of H3K9me3 in Depression and Suicide. Int J Neuropsychopharmacol 2016; 20:50-57. [PMID: 27516431 PMCID: PMC5737582 DOI: 10.1093/ijnp/pyw071] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Major depressive disorder has been associated with dysfunctional astrocytic networks. The underlying causes, extent, and consequences of such dysfunctions remain to be characterized. Astrocyte-astrocyte communication occurs principally through gap junction channels primarily formed by connexin 30 and 43 (CX30 and CX43). We previously reported decreased connexin expression in the prefrontal cortex of depressed suicides. In the present study, we investigated whether these changes are mediated by epigenetic regulation, and expanded gene expression quantifications to other cortical and subcortical regions to assess the regional distribution of connexion disruptions in depressed suicides. METHODS The expression of CX30 and CX43 was measured by real-time PCR in samples of neocortex (Brodmann areas 4 and 17), cerebellar cortex, mediodorsal thalamus, and caudate nucleus of 22 depressed suicides and 22 matched sudden-death controls. Chromatin immunoprecipitation was used to measure enrichment levels of the repressive chromatin mark H3K9me3 in the prefrontal cortex. RESULTS We found a consistent downregulation of connexin genes in all regions examined, except in the cerebellum where an increase in the expression of CX30 was measured and using chromatin immunoprecipitation we observed an enrichment of H3K9me3 for both Cx30 and Cx43 in the prefrontal cortex. CONCLUSIONS Our study shows widespread astrocytic CX gene repression in depressed suicides that is mediated, at least in part, through epigenetic mechanisms. Taken together, these findings support the notion of widespread cerebral astrocytic dysfunction in major depressive disorder.
Collapse
Affiliation(s)
- Corina Nagy
- McGill Group for Suicide Studies, Douglas Mental Health University Institute (Ms Nagy, Drs Torres-Platas, Machawar, and Turecki); Departments of Neurology and Neurosurgery (Ms Nagy, Drs Torres-Platas, Machawar, and Turecki), Human Genetics (Dr Turecki), and Psychiatry (Drs Mechawar and Turecki), McGill University, Verdun, Québec, Canada
| | - Susana G. Torres-Platas
- McGill Group for Suicide Studies, Douglas Mental Health University Institute (Ms Nagy, Drs Torres-Platas, Machawar, and Turecki); Departments of Neurology and Neurosurgery (Ms Nagy, Drs Torres-Platas, Machawar, and Turecki), Human Genetics (Dr Turecki), and Psychiatry (Drs Mechawar and Turecki), McGill University, Verdun, Québec, Canada
| | - Naguib Mechawar
- McGill Group for Suicide Studies, Douglas Mental Health University Institute (Ms Nagy, Drs Torres-Platas, Machawar, and Turecki); Departments of Neurology and Neurosurgery (Ms Nagy, Drs Torres-Platas, Machawar, and Turecki), Human Genetics (Dr Turecki), and Psychiatry (Drs Mechawar and Turecki), McGill University, Verdun, Québec, Canada
| | | |
Collapse
|
45
|
Augustin V, Bold C, Wadle SL, Langer J, Jabs R, Philippot C, Weingarten DJ, Rose CR, Steinhäuser C, Stephan J. Functional anisotropic panglial networks in the lateral superior olive. Glia 2016; 64:1892-911. [PMID: 27458984 DOI: 10.1002/glia.23031] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 06/24/2016] [Accepted: 06/30/2016] [Indexed: 12/12/2022]
Abstract
Astrocytes form large gap junctional networks that contribute to ion and neurotransmitter homeostasis. Astrocytes concentrate in the lateral superior olive (LSO), a prominent auditory brainstem center. Compared to the LSO, astrocyte density is lower in the region dorsal to the LSO (dLSO) and in the internuclear space between the LSO, the superior paraolivary nucleus (SPN). We questioned whether astrocyte networks exhibit certain properties that reflect the precise neuronal arrangement. Employing whole-cell patch-clamp and concomitant injection of a gap junction-permeable tracer, we analyzed size and orientation of astrocyte networks in LSO, dLSO, and SPN-LSO in acute brainstem slices of mice at postnatal days 10-20. The majority of LSO networks exhibited an oval topography oriented orthogonally to the tonotopic axis, whereas dLSO networks showed no preferred orientation. This correlated with the overall astrocyte morphology in both regions, i.e. LSO astrocyte processes were oriented mainly orthogonally to the tonotopic axis. To assess the spread of small ions within LSO networks, we analyzed the diffusion of Na(+) signals between cells using Na(+) imaging. We found that Na(+) not only diffused between SR101(+) astrocytes, but also from astrocytes into SR101(-) cells. Using PLP-GFP mice for tracing, we could show that LSO networks contained astrocytes and oligodendrocytes. Together, our results demonstrate that LSO astrocytes and LSO oligodendrocytes form functional anisotropic panglial networks that are oriented predominantly orthogonally to the tonotopic axis. Thus, our results point toward an anisotropic ion and metabolite diffusion and a limited glial crosstalk between neighboring isofrequency bands in the LSO. GLIA 2016;64:1892-1911.
Collapse
Affiliation(s)
- Vanessa Augustin
- Department of Biology, Animal Physiology Group, University of Kaiserslautern, Erwin Schroedinger-Strasse 13, Kaiserslautern, Germany
| | - Charlotte Bold
- Department of Biology, Animal Physiology Group, University of Kaiserslautern, Erwin Schroedinger-Strasse 13, Kaiserslautern, Germany
| | - Simon L Wadle
- Department of Biology, Animal Physiology Group, University of Kaiserslautern, Erwin Schroedinger-Strasse 13, Kaiserslautern, Germany
| | - Julia Langer
- Institute of Neurobiology, Universitaetsstasse 1, Heinrich Heine University Duesseldorf, Duesseldorf, Germany
| | - Ronald Jabs
- Medical Faculty, Institute of Cellular Neurosciences, University of Bonn, Sigmund-Freud-Strasse 25, Bonn, Germany
| | - Camille Philippot
- Medical Faculty, Institute of Cellular Neurosciences, University of Bonn, Sigmund-Freud-Strasse 25, Bonn, Germany
| | - Dennis J Weingarten
- Department of Biology, Animal Physiology Group, University of Kaiserslautern, Erwin Schroedinger-Strasse 13, Kaiserslautern, Germany
| | - Christine R Rose
- Institute of Neurobiology, Universitaetsstasse 1, Heinrich Heine University Duesseldorf, Duesseldorf, Germany
| | - Christian Steinhäuser
- Medical Faculty, Institute of Cellular Neurosciences, University of Bonn, Sigmund-Freud-Strasse 25, Bonn, Germany
| | - Jonathan Stephan
- Department of Biology, Animal Physiology Group, University of Kaiserslautern, Erwin Schroedinger-Strasse 13, Kaiserslautern, Germany.
| |
Collapse
|
46
|
Potential Therapies by Stem Cell-Derived Exosomes in CNS Diseases: Focusing on the Neurogenic Niche. Stem Cells Int 2016; 2016:5736059. [PMID: 27195011 PMCID: PMC4853949 DOI: 10.1155/2016/5736059] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 03/27/2016] [Indexed: 12/31/2022] Open
Abstract
Neurodegenerative disorders are one of the leading causes of death and disability and one of the biggest burdens on health care systems. Novel approaches using various types of stem cells have been proposed to treat common neurodegenerative disorders such as Alzheimer's Disease, Parkinson's Disease, or stroke. Moreover, as the secretome of these cells appears to be of greater benefit compared to the cells themselves, the extracellular components responsible for its therapeutic benefit have been explored. Stem cells, as well as most cells, release extracellular vesicles such as exosomes, which are nanovesicles able to target specific cell types and thus to modify their function by delivering proteins, lipids, and nucleic acids. Exosomes have recently been tested in vivo and in vitro as therapeutic conveyors for the treatment of diseases. As such, they could be engineered to target specific populations of cells within the CNS. Considering the fact that many degenerative brain diseases have an impact on adult neurogenesis, we discuss how the modulation of the adult neurogenic niches may be a therapeutic target of stem cell-derived exosomes. These novel approaches should be examined in cellular and animal models to provide better, more effective, and specific therapeutic tools in the future.
Collapse
|
47
|
Lee CY, Dallérac G, Ezan P, Anderova M, Rouach N. Glucose Tightly Controls Morphological and Functional Properties of Astrocytes. Front Aging Neurosci 2016; 8:82. [PMID: 27148048 PMCID: PMC4834307 DOI: 10.3389/fnagi.2016.00082] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 04/01/2016] [Indexed: 01/14/2023] Open
Abstract
The main energy source powering the brain is glucose. Strong energy needs of our nervous system are fulfilled by conveying this essential metabolite through blood via an extensive vascular network. Glucose then reaches brain tissues by cell uptake, diffusion and metabolization, processes primarily undertaken by astrocytes. Deprivation of glucose can however occur in various circumstances. In particular, ageing is associated with cognitive disturbances that are partly attributable to metabolic deficiency leading to brain glycopenia. Despite the crucial role of glucose and its metabolites in sustaining neuronal activity, little is known about its moment-to-moment contribution to astroglial physiology. We thus here investigated the early structural and functional alterations induced in astrocytes by a transient metabolic challenge consisting in glucose deprivation. Electrophysiological recordings of hippocampal astroglial cells of the stratum radiatumin situ revealed that shortage of glucose specifically increases astrocyte membrane capacitance, whilst it has no impact on other passive membrane properties. Consistent with this change, morphometric analysis unraveled a prompt increase in astrocyte volume upon glucose deprivation. Furthermore, characteristic functional properties of astrocytes are also affected by transient glucose deficiency. We indeed found that glucoprivation decreases their gap junction-mediated coupling, while it progressively and reversibly increases their intracellular calcium levels during the slow depression of synaptic transmission occurring simultaneously, as assessed by dual electrophysiological and calcium imaging recordings. Together, these data indicate that astrocytes rapidly respond to metabolic dysfunctions, and are therefore central to the neuroglial dialog at play in brain adaptation to glycopenia.
Collapse
Affiliation(s)
- Chun-Yao Lee
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, Centre National de la Recherche Scientifique UMR 7241, Institut National de la Santé et de la Recherche Médicale U1050, Labex Memolife, PSL Research University Paris, France
| | - Glenn Dallérac
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, Centre National de la Recherche Scientifique UMR 7241, Institut National de la Santé et de la Recherche Médicale U1050, Labex Memolife, PSL Research University Paris, France
| | - Pascal Ezan
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, Centre National de la Recherche Scientifique UMR 7241, Institut National de la Santé et de la Recherche Médicale U1050, Labex Memolife, PSL Research University Paris, France
| | - Miroslava Anderova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech RepublicPrague, Czech Republic; Department of Neuroscience, 2nd Faculty of Medicine, Charles UniversityPrague, Czech Republic
| | - Nathalie Rouach
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, Centre National de la Recherche Scientifique UMR 7241, Institut National de la Santé et de la Recherche Médicale U1050, Labex Memolife, PSL Research University Paris, France
| |
Collapse
|
48
|
Chever O, Dossi E, Pannasch U, Derangeon M, Rouach N. Astroglial networks promote neuronal coordination. Sci Signal 2016; 9:ra6. [DOI: 10.1126/scisignal.aad3066] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
|
49
|
Müller A, Stellmacher A, Freitag CE, Landgraf P, Dieterich DC. Monitoring Astrocytic Proteome Dynamics by Cell Type-Specific Protein Labeling. PLoS One 2015; 10:e0145451. [PMID: 26690742 PMCID: PMC4686566 DOI: 10.1371/journal.pone.0145451] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 12/03/2015] [Indexed: 01/13/2023] Open
Abstract
The ability of the nervous system to undergo long-term plasticity is based on changes in cellular and synaptic proteomes. While many studies have explored dynamic alterations in neuronal proteomes during plasticity, there has been less attention paid to the astrocytic counterpart. Indeed, progress in identifying cell type-specific proteomes is limited owing to technical difficulties. Here, we present a cell type-specific metabolic tagging technique for a mammalian coculture model based on the bioorthogonal amino acid azidonorleucine and the mutated Mus musculus methionyl-tRNA synthetaseL274G enabling azidonorleucine introduction into de novo synthesized proteins. Azidonorleucine incorporation resulted in cell type-specific protein labeling and retained neuronal or astrocytic cell viability. Furthermore, we were able to label astrocytic de novo synthesized proteins and identified both Connexin-43 and 60S ribosomal protein L10a upregulated upon treatment with Brain-derived neurotrophic factor in astrocytes of a neuron-glia coculture. Taken together, we demonstrate the successful dissociation of astrocytic from neuronal proteomes by cell type-specific metabolic labeling offering new possibilities for the analyses of cell type-specific proteome dynamics.
Collapse
Affiliation(s)
- Anke Müller
- Neural Plasticity and Communication, Institute for Pharmacology and Toxicology, Otto–von–Guericke–University Magdeburg, Magdeburg, Germany
| | - Anne Stellmacher
- Neural Plasticity and Communication, Institute for Pharmacology and Toxicology, Otto–von–Guericke–University Magdeburg, Magdeburg, Germany
| | - Christine E. Freitag
- Research Group Neuralomics, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Peter Landgraf
- Neural Plasticity and Communication, Institute for Pharmacology and Toxicology, Otto–von–Guericke–University Magdeburg, Magdeburg, Germany
| | - Daniela C. Dieterich
- Neural Plasticity and Communication, Institute for Pharmacology and Toxicology, Otto–von–Guericke–University Magdeburg, Magdeburg, Germany
- Research Group Neuralomics, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Center for Behavioral Brain Sciences, Magdeburg, Germany
- * E-mail:
| |
Collapse
|
50
|
Del Rio R, Quintanilla RA, Orellana JA, Retamal MA. Neuron-Glia Crosstalk in the Autonomic Nervous System and Its Possible Role in the Progression of Metabolic Syndrome: A New Hypothesis. Front Physiol 2015; 6:350. [PMID: 26648871 PMCID: PMC4664731 DOI: 10.3389/fphys.2015.00350] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 11/09/2015] [Indexed: 01/26/2023] Open
Abstract
Metabolic syndrome (MS) is characterized by the following physiological alterations: increase in abdominal fat, insulin resistance, high concentration of triglycerides, low levels of HDL, high blood pressure, and a generalized inflammatory state. One of the pathophysiological hallmarks of this syndrome is the presence of neurohumoral activation, which involve autonomic imbalance associated to hyperactivation of the sympathetic nervous system. Indeed, enhanced sympathetic drive has been linked to the development of endothelial dysfunction, hypertension, stroke, myocardial infarct, and obstructive sleep apnea. Glial cells, the most abundant cells in the central nervous system, control synaptic transmission, and regulate neuronal function by releasing bioactive molecules called gliotransmitters. Recently, a new family of plasma membrane channels called hemichannels has been described to allow the release of gliotransmitters and modulate neuronal firing rate. Moreover, a growing amount of evidence indicates that uncontrolled hemichannel opening could impair glial cell functions, affecting synaptic transmission and neuronal survival. Given that glial cell functions are disturbed in various metabolic diseases, we hypothesize that progression of MS may relies on hemichannel-dependent impairment of glial-to-neuron communication by a mechanism related to dysfunction of inflammatory response and mitochondrial metabolism of glial cells. In this manuscript, we discuss how glial cells may contribute to the enhanced sympathetic drive observed in MS, and shed light about the possible role of hemichannels in this process.
Collapse
Affiliation(s)
- Rodrigo Del Rio
- Centro de Investigación Biomédica, Universidad Autónoma de Chile Santiago, Chile ; Dirección de Investigación, Universidad Científica del Sur Lima, Perú
| | | | - Juan A Orellana
- Departamento de Neurología, Escuela de Medicina, Pontificia Universidad Católica de Chile Santiago, Chile
| | - Mauricio A Retamal
- Centro de Fisiología Celular e Integrativa, Facultad de Medicina. Clínica Alemana Universidad del Desarrollo Santiago, Chile
| |
Collapse
|