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Talaverón R, Morado-Díaz CJ, Herrera A, Gálvez V, Pastor AM, Matarredona ER. The Gap Junction Inhibitor Octanol Decreases Proliferation and Increases Glial Differentiation of Postnatal Neural Progenitor Cells. Int J Mol Sci 2024; 25:6288. [PMID: 38927995 PMCID: PMC11203596 DOI: 10.3390/ijms25126288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2024] [Revised: 05/30/2024] [Accepted: 06/04/2024] [Indexed: 06/28/2024] Open
Abstract
Neural precursor cells (NPCs) that persist in the postnatal/adult subventricular zone (SVZ) express connexins that form hemichannels and gap junctions. Gap junctional communication plays a role in NPC proliferation and differentiation during development, but its relevance on postnatal age remains to be elucidated. In this work we aimed to evaluate the effect of the blockade of gap junctional communication on proliferation and cell fate of NPCs obtained from the SVZ of postnatal rats. NPCs were isolated and expanded in culture as neurospheres. Electron microscopy revealed the existence of gap junctions among neurosphere cells. Treatment of cultures with octanol, a broad-spectrum gap junction blocker, or with Gap27, a specific blocker for gap junctions formed by connexin43, produced a significant decrease in bromodeoxyuridine incorporation. Octanol treatment also exerted a dose-dependent antiproliferative effect on glioblastoma cells. To analyze possible actions on NPC fate, cells were seeded in the absence of mitogens. Treatment with octanol led to an increase in the percentage of astrocytes and oligodendrocyte precursors, whereas the percentage of neurons remained unchanged. Gap27 treatment, in contrast, did not modify the differentiation pattern of SVZ NPCs. Our results indicate that general blockade of gap junctions with octanol induces significant effects on the behavior of postnatal SVZ NPCs, by reducing proliferation and promoting glial differentiation.
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Affiliation(s)
- Rocío Talaverón
- Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Sevilla, 41012 Seville, Spain;
- Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain; (C.J.M.-D.); (A.M.P.)
| | - Camilo J. Morado-Díaz
- Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain; (C.J.M.-D.); (A.M.P.)
| | - Alejandro Herrera
- Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain; (C.J.M.-D.); (A.M.P.)
| | - Victoria Gálvez
- Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain; (C.J.M.-D.); (A.M.P.)
| | - Angel M. Pastor
- Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain; (C.J.M.-D.); (A.M.P.)
| | - Esperanza R. Matarredona
- Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain; (C.J.M.-D.); (A.M.P.)
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Papadakos SP, Chatzikalil E, Arvanitakis K, Vakadaris G, Stergiou IE, Koutsompina ML, Argyrou A, Lekakis V, Konstantinidis I, Germanidis G, Theocharis S. Understanding the Role of Connexins in Hepatocellular Carcinoma: Molecular and Prognostic Implications. Cancers (Basel) 2024; 16:1533. [PMID: 38672615 PMCID: PMC11048329 DOI: 10.3390/cancers16081533] [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: 03/25/2024] [Revised: 04/15/2024] [Accepted: 04/16/2024] [Indexed: 04/28/2024] Open
Abstract
Connexins, a family of tetraspan membrane proteins forming intercellular channels localized in gap junctions, play a pivotal role at the different stages of tumor progression presenting both pro- and anti-tumorigenic effects. Considering the potential role of connexins as tumor suppressors through multiple channel-independent mechanisms, their loss of expression may be associated with tumorigenic activity, while it is hypothesized that connexins favor the clonal expansion of tumor cells and promote cell migration, invasion, and proliferation, affecting metastasis and chemoresistance in some cases. Hepatocellular carcinoma (HCC), characterized by unfavorable prognosis and limited responsiveness to current therapeutic strategies, has been linked to gap junction proteins as tumorigenic factors with prognostic value. Notably, several members of connexins have emerged as promising markers for assessing the progression and aggressiveness of HCC, as well as the chemosensitivity and radiosensitivity of hepatocellular tumor cells. Our review sheds light on the multifaceted role of connexins in HCC pathogenesis, offering valuable insights on recent advances in determining their prognostic and therapeutic potential.
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Affiliation(s)
- Stavros P. Papadakos
- First Department of Pathology, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece; (S.P.P.); (E.C.)
| | - Elena Chatzikalil
- First Department of Pathology, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece; (S.P.P.); (E.C.)
| | - Konstantinos Arvanitakis
- Division of Gastroenterology and Hepatology, First Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (K.A.); (G.V.)
- Basic and Translational Research Unit, Special Unit for Biomedical Research and Education, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece
| | - Georgios Vakadaris
- Division of Gastroenterology and Hepatology, First Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (K.A.); (G.V.)
| | - Ioanna E. Stergiou
- Pathophysiology Department, School of Medicine, National and Kapodistrian University of Athens, 11527 Athens, Greece; (I.E.S.); (M.-L.K.)
| | - Maria-Loukia Koutsompina
- Pathophysiology Department, School of Medicine, National and Kapodistrian University of Athens, 11527 Athens, Greece; (I.E.S.); (M.-L.K.)
| | - Alexandra Argyrou
- Academic Department of Gastroenterology, Laikon General Hospital, Athens University Medical School, 11527 Athens, Greece; (A.A.); (V.L.)
| | - Vasileios Lekakis
- Academic Department of Gastroenterology, Laikon General Hospital, Athens University Medical School, 11527 Athens, Greece; (A.A.); (V.L.)
| | | | - Georgios Germanidis
- Division of Gastroenterology and Hepatology, First Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (K.A.); (G.V.)
- Basic and Translational Research Unit, Special Unit for Biomedical Research and Education, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece
| | - Stamatios Theocharis
- First Department of Pathology, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece; (S.P.P.); (E.C.)
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Cao JW, Liu LY, Yu YC. Gap junctions regulate the development of neural circuits in the neocortex. Curr Opin Neurobiol 2023; 81:102735. [PMID: 37263136 DOI: 10.1016/j.conb.2023.102735] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 04/12/2023] [Accepted: 05/07/2023] [Indexed: 06/03/2023]
Abstract
Gap junctions between cells are ubiquitously expressed in the developing brain. They are involved in major steps of neocortical development, including neurogenesis, cell migration, synaptogenesis, and neural circuit formation, and have been implicated in cortical column formation. Dysfunctional gap junctions can contribute to or even cause a variety of brain diseases. Although the role of gap junctions in neocortical development is better known, a comprehensive understanding of their functions is far from complete. Here we explore several critical open questions surrounding gap junctions and their involvement in neural circuit development. Addressing them will greatly impact our understanding of the fundamental mechanisms of neocortical structure and function as well as the etiology of brain disease.
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Affiliation(s)
- Jun-Wei Cao
- School of Basic Medical Sciences, Xiangnan University, Chenzhou, Hunan 423000, China
| | - Lin-Yun Liu
- Jing'an District Central Hospital of Shanghai, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Institutes of Brain Science, Shanghai 200032, China
| | - Yong-Chun Yu
- Jing'an District Central Hospital of Shanghai, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Institutes of Brain Science, Shanghai 200032, China.
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Xu C, Zhong W, Zhang H, Jiang J, Zhou H. Gap26 inhibited angiogenesis through the β-catenin-VE-cadherin-VEGFR2-Erk signaling pathway. Life Sci 2023:121836. [PMID: 37295713 DOI: 10.1016/j.lfs.2023.121836] [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: 04/18/2023] [Revised: 05/22/2023] [Accepted: 06/04/2023] [Indexed: 06/12/2023]
Abstract
PURPOSE To investigate the effect of connexin 43 (Cx43) on corneal neovascularization and its regulation of VEGFR2 on vascular endothelial cells. METHODS In vivo, we used mouse corneal suture model to induce corneal neovascularization and discovered the function of gap26 in corneal neovascularization. In vitro, the effect of gap26 on HUVEC was observed by cell proliferation, tube formation and scratch experiments. WB and PCR detected the changes in angiogenic protein and mRNA expression. Knockdown of key mRNA in neovascularization using siRNA confirmed that Cx43 regulates neovascularization through the β-catenin-VE-cadherin-VEGFR2-Erk signaling pathway. RESULTS In vivo, gap26 can reduce mouse corneal neovascularization. In vitro, we show that Cx43 expression is increased in the presence of VEGFA stimulation, and when we use gap26 to inhibit Cx43 can reduce vascular endothelial cell proliferation, tube formation and migration. We found that the expression of pVEGFR2 and pErk increased in response to VEGFA, while they decreased after using gap26. And the expression of β-catenin and VE-cadherin decreased in response to VEGFA, while they increased after using gap26. Furthermore, we found that Cx43 regulates angiogenesis through the β-catenin-VE-cadherin-VEGFR2-Erk pathway. CONCLUSIONS Gap26 can downregulate VEGFR2 phosphorylation by stabilizing the expression of β-catenin and VE-cadherin on the cell membrane, thereby inhibiting VEGFA-induced HUVECs proliferation, migration and tube formation and inhibiting corneal neovascularization.
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Affiliation(s)
- Chuyang Xu
- Department of Ophthalmology, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China
| | - Wei Zhong
- Department of Ophthalmology, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China
| | - Hong Zhang
- Department of Ophthalmology, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China
| | - Jinlan Jiang
- Scientific Research Center, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China.
| | - Hongyan Zhou
- Department of Ophthalmology, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China.
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Wu L, Jiang T, Fu Z, Wang L, You H, Xue J, Luo D. Connexin 43 dephosphorylation at serine 282 induces spontaneous arrhythmia and increases susceptibility to ischemia/reperfusion injury. Heliyon 2023; 9:e15879. [PMID: 37215881 PMCID: PMC10196788 DOI: 10.1016/j.heliyon.2023.e15879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 04/23/2023] [Accepted: 04/25/2023] [Indexed: 05/24/2023] Open
Abstract
Background Connexin 43 (Cx43), the predominant gap junction protein in hearts, is modified by specific (de)phosphorylation events under physiological and pathological states to affect myocardium function and structure. Previously we found that deficiency in Cx43 S282 phosphorylation could impair intercellular communication and contribute to cardiomyocyte apoptosis by activating p38 mitogen-activated protein kinase (p38 MAPK)/factor-associated suicide (Fas)/Fas-associating protein with a novel death domain (FADD) pathway, which is involved in myocardium injury in ischemia/reperfusion (I/R) heart. In addition, mutant at Cx43 S282 substituted with alanine heterozygous mice (S282A+/-) exhibited different degrees of ventricular arrhythmias and only some underwent myocardium apoptosis. In this study, we aimed to investigate the role of Cx43 pS282 in different cardiac pathological phenotypes. Methods We examined cardiac function, structure, and relevant protein expression in S282A+/- mice (aged 2, 10 and 30 weeks) by electrocardiograph, echocardiography, histological staining, and co-immunoprecipitation followed by Western blot. Intraperitoneal isoprenaline injection and I/R surgery were applied in S282A+/- mice as external stimulus. 2,3,5-triphenyltetrazolium chloride staining was used for myocardium infarction evaluation. Results Adult S282A+/- mice (aged 10 and 30 weeks) still exhibited spontaneous arrhythmia. Unlike neonatal stage (aged around 2 weeks), no apoptosis-related manifestations and the activation of p38 MAPK-Fas-FADD apoptotic pathway were observed in adult S282A+/- hearts. S282A+/- neonatal mice with cardiomyocytes apoptosis exhibited more than 60% dephosphorylation at Cx43 S282 than WT mice, while less than 40% S282 dephosphorylation were found in adult S282A+/- mice. In addition, although S282A+/- mice displayed normal cardiac function, they were highly susceptible to isoproterenol-induced ECG alternans and prone to cardiac injury and deaths upon I/R attack. Conclusions These results reinforce that Cx43 S282 dephosphorylation acts as a susceptibility factor in regulating cardiomyocyte survival and cardiac electrical homeostasis in basal conditions and contributes to myocardium injury in the setting of I/R. Cx43 S282 phosphorylation was competent to induce spontaneous arrhythmias, cardiomyocyte apoptosis and deaths based on the degree of S282 dephosphorylation.
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Affiliation(s)
- Lulin Wu
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, PR China
| | - Tianhui Jiang
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, PR China
| | - Zhiping Fu
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, PR China
| | - Luqi Wang
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, PR China
| | - Hongjie You
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, PR China
| | - Jingyi Xue
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, PR China
| | - Dali Luo
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, PR China
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Liu S, Lan Y, Zhao Y, Zhang Q, Lin T, Lin K, Guo J, Yan Y. Expression of connexin 43 protein in cardiomyocytes of heart failure mouse model. Front Cardiovasc Med 2022; 9:1028558. [PMID: 36277751 PMCID: PMC9581147 DOI: 10.3389/fcvm.2022.1028558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 09/21/2022] [Indexed: 11/13/2022] Open
Abstract
Heart failure (HF) is the end stage of various cardiovascular diseases, with high morbidity and mortality, and is associated with a poor prognosis. One of the primary causes of HF is aortic valve disease, manifested by progressive aortic valve stenosis (AVS), resulting in increased left ventricular load, ventricular hypertrophy, ultimately ventricular dysfunction, and HF. Early assessment of the degree of cardiomyopathy and timely intervention is expected to improve patients’ cardiac function and delay or even avoid the occurrence of HF. The Wnt signaling pathway is mainly involved in regulating myocardial insufficiency after valve stenosis. Connexin 43 protein (Cx43) is an essential target of Wnt signaling pathway that forms gap junction (GJ) structures and is widely distributed in various organs and tissues, especially in the heart. The distribution and transformation of Cx43 among cardiac cells are crucial for the development of HF. To specifically label Cx43 in vivo, we established a new Cx43-BFP-GFP mouse model with two loxp sites on both sides of the tag BFP-polyA box, which can be removed by Cre recombination. This double-reporter line endowed us with a powerful genetic tool for determining the area, spatial distribution, and functional status of Cx43. It also indicated changes in electrical conduction between cells in a steady or diseased state.
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Affiliation(s)
- Shaoyan Liu
- Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yang Lan
- Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yun Zhao
- Department of Cardiac Surgery, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Qianyu Zhang
- School of Life Sciences and Technology, Shanghai Tech University, Shanghai, China
| | - Tzuchun Lin
- Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Kaibin Lin
- Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Junjie Guo
- Department of Cardiology, The Affiliated Hospital of Qingdao University, Qingdao, China,Qingdao Municipal Key Laboratory of Hypertension (Key Laboratory of Cardiovascular Medicine), Qingdao, China,*Correspondence: Junjie Guo,
| | - Yan Yan
- Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai, China,Yan Yan,
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GJA1/CX43 High Expression Levels in the Cervical Spinal Cord of ALS Patients Correlate to Microglia-Mediated Neuroinflammatory Profile. Biomedicines 2022; 10:biomedicines10092246. [PMID: 36140348 PMCID: PMC9496195 DOI: 10.3390/biomedicines10092246] [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: 08/14/2022] [Revised: 09/04/2022] [Accepted: 09/07/2022] [Indexed: 11/17/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder affecting motoneurons (MNs) with a fatal outcome. The typical degeneration of cortico-spinal, spinal, and bulbar MNs, observed in post-mortem biopsies, is associated with the activation of neuroimmune cells. GJA1, a member of the connexins (Cxs) gene family, encodes for connexin 43 (Cx43), a core gap junctions (GJs)- and hemichannels (HCs)-forming protein, involved in cell death, proliferation, and differentiation. Recently, Cx43 expression was found to play a role in ALS pathogenesis. Here, we used microarray and RNA-seq datasets from the NCBI of the spinal cord of control (NDC) and ALS patients, which were stratified according to the GJA1 gene expression. Genes that positively or negatively correlated to GJA1 expression were used to perform a genomic deconvolution analysis (GDA) using neuroimmune signatures. Expression analysis revealed a significantly higher GJA1 expression in the MNs of ALS patients as compared to NDC. Gene deconvolution analysis revealed that positively correlated genes were associated with microglia activation, whereas negatively correlated genes were associated with neuronal activation profiles. Moreover, gene ontology analysis, performed on genes characterizing either microglia or neuronal signature, indicated immune activation or neurogenesis as main biological processes. Finally, using a synthetic analysis of drugs able to revert the GJA1 transcriptomic signatures, we found a specific drug profile for ALS patients with high GJA1 expression levels, composed of amlodipine, sertraline, and prednisolone. In conclusion, our exploratory study suggests GJA1 as a new neuro-immunological gene correlated to microglial cellular profile in the spinal cord of ALS patients. Further studies are warranted to confirm these results and to evaluate the therapeutic potential of drugs able to revert typical GJA1/CX43 signature in ALS patients
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Novel Approaches Used to Examine and Control Neurogenesis in Parkinson's Disease. Int J Mol Sci 2021; 22:ijms22179608. [PMID: 34502516 PMCID: PMC8431772 DOI: 10.3390/ijms22179608] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/31/2021] [Accepted: 09/02/2021] [Indexed: 12/16/2022] Open
Abstract
Neurogenesis is a key mechanism of brain development and plasticity, which is impaired in chronic neurodegeneration, including Parkinson’s disease. The accumulation of aberrant α-synuclein is one of the features of PD. Being secreted, this protein produces a prominent neurotoxic effect, alters synaptic plasticity, deregulates intercellular communication, and supports the development of neuroinflammation, thereby providing propagation of pathological events leading to the establishment of a PD-specific phenotype. Multidirectional and ambiguous effects of α-synuclein on adult neurogenesis suggest that impaired neurogenesis should be considered as a target for the prevention of cell loss and restoration of neurological functions. Thus, stimulation of endogenous neurogenesis or cell-replacement therapy with stem cell-derived differentiated neurons raises new hopes for the development of effective and safe technologies for treating PD neurodegeneration. Given the rapid development of optogenetics, it is not surprising that this method has already been repeatedly tested in manipulating neurogenesis in vivo and in vitro via targeting stem or progenitor cells. However, niche astrocytes could also serve as promising candidates for controlling neuronal differentiation and improving the functional integration of newly formed neurons within the brain tissue. In this review, we mainly focus on current approaches to assess neurogenesis and prospects in the application of optogenetic protocols to restore the neurogenesis in Parkinson’s disease.
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Won DH, Hwang DB, Shin YS, Kim SY, Kim C, Hong IS, Kang BC, Che JH, Yun JW. Cellular signaling crosstalk between Wnt signaling and gap junctions inbenzo[a]pyrene toxicity. Cell Biol Toxicol 2021; 39:165-182. [PMID: 34283317 DOI: 10.1007/s10565-021-09630-z] [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: 03/29/2021] [Accepted: 06/24/2021] [Indexed: 11/29/2022]
Abstract
Gap junctional intercellular communication (GJIC) is considered a key biological mechanism to maintain homeostasis in cell differentiation and growth. In addition, as another major signaling pathway associated with cell proliferation and differentiation, Wnt/β-catenin signaling appears to trigger several cellular responses against injury. The purpose of the present study was to investigate the effects of a known toxic agent, benzo[a]pyrene (BaP), on the regulation and interaction between GJIC and Wnt/β-catenin signaling. BaP treatment resulted in GJIC inhibition and decreases the major GJIC protein connexin 43 (Cx43) in WB-F344 rat liver epithelial cells. We also found BaP-mediated downregulation of Wnt/β-catenin signaling related to the PI3K-Akt pathway. To identify the relationship between GJIC and Wnt/β-catenin signaling, we treated WB-F344 cells with the Wnt agonist CHIR99021 and found that it inhibited GJIC while causing a significant reduction in Cx43 expression at both the mRNA and protein levels, through the repression of promoter activity. This Wnt agonist-mediated GJIC inhibition was confirmed using a small interfering RNA directed against the Wnt antagonist Dact2, indicating that Wnt/β-catenin signaling negatively regulates GJIC. Despite the inverse correlation between Wnt/β-catenin signaling and Cx43 promoter activation as indicated by downregulation of β-catenin nuclear translocation and upregulation of Cx43 promoter activation involving HNF3β, BaP treatment decreased the Cx43 protein expression, which was associated with protein degradation, possibly through protein kinase C activation. In conclusion, our results revealed the mechanism of BaP-induced inhibition of GJIC and Wnt/β-catenin signaling. More importantly, linking Wnt/β-catenin signaling to Cx protein expression will have profound implications in understanding the relationships among different major signaling pathways associated with cell proliferation and differentiation in toxicity.
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Affiliation(s)
- Dong-Hoon Won
- Department of Biotechnology, The Catholic University of Korea, Bucheon, 14662, South Korea
| | - Da-Bin Hwang
- Department of Biotechnology, The Catholic University of Korea, Bucheon, 14662, South Korea
| | - Yoo-Sub Shin
- Department of Biotechnology, The Catholic University of Korea, Bucheon, 14662, South Korea
| | - Shin-Young Kim
- Department of Biotechnology, The Catholic University of Korea, Bucheon, 14662, South Korea
| | - Changuk Kim
- Department of Biotechnology, The Catholic University of Korea, Bucheon, 14662, South Korea
| | - In-Sun Hong
- Department of Molecular Medicine, School of Medicine, Gachon University, Incheon, 21999, South Korea
| | - Byeong-Cheol Kang
- Graduate School of Translational Medicine, Seoul National University College of Medicine, Seoul, 03080, South Korea
| | - Jeong-Hwan Che
- Biomedical Center for Animal Resource and Development, Seoul National University College of Medicine, Seoul, 03080, South Korea.
| | - Jun-Won Yun
- Department of Biotechnology, The Catholic University of Korea, Bucheon, 14662, South Korea. .,Department of Medical and Biological Sciences, The Catholic University of Korea, Bucheon, 14662, Republic of Korea.
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Cho HJ, Velichkovska M, Schurhoff N, András IE, Toborek M. Extracellular vesicles regulate gap junction-mediated intercellular communication and HIV-1 infection of human neural progenitor cells. Neurobiol Dis 2021; 155:105388. [PMID: 33962010 DOI: 10.1016/j.nbd.2021.105388] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 04/13/2021] [Accepted: 05/03/2021] [Indexed: 12/11/2022] Open
Abstract
Human immunodeficiency virus-1 (HIV-1) has been shown to cross the blood-brain barrier and cause HIV-associated neurocognitive disorders (HAND) through a process that may involve direct or indirect interactions with the central nervous system (CNS) cells and alterations of amyloid β (Aβ) homeostasis. The present study focused on the mechanisms of HIV-1 infecting human neural progenitor cells (hNPCs) and affecting NPC intercellular communications with human brain endothelial cells (HBMEC). Despite the lack of the CD4 receptor, hNPCs were effectively infected by HIV-1 via a mechanism involving the chemokine receptors, CXCR4 and CCR5. HIV-1 infection increased expression of connexin-43 (Cx43), phosphorylated Cx43 (pCx43), and pannexin 2 (Panx2) protein levels in hNPCs, suggesting alterations in gap-junction (GJ) and pannexin channel communication. Indeed, a functional GJ assay indicated an increase in communication between HIV-infected hNPCs and non-infected HBMEC. We next analyzed the impact of HBMEC-derived extracellular vesicles (EVs) and EVs carrying Aβ (EV-Aβ) on the expression of Cx43, pCx43, and Panx2 in HIV-1 infected and non-infected hNPCs. Exposure to EV-Aβ resulted in significant reduction of Cx43 and pCx43 protein expression in non-infected hNPCs when compared to EV controls. Interestingly, EV-Aβ treatment significantly increased levels of Cx43, pCx43, and Panx2 in HIV-1-infected hNPCs when compared to non-infected controls. These results were confirmed in a GJ functional assay and an ATP release assay, which is an indicator of connexin hemichannel and/or pannexin channel functions. Overall, the current study demonstrates the importance of hNPCs in HIV-1 infection and indicates that intercellular communications between infected hNPCs and HBMEC can be effectively modulated by EVs carrying Aβ as their cargo.
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Affiliation(s)
- Hyung Joon Cho
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, 33136, USA.
| | - Martina Velichkovska
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - Nicolette Schurhoff
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - Ibolya E András
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - Michal Toborek
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, 33136, USA.
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Connexins in the Heart: Regulation, Function and Involvement in Cardiac Disease. Int J Mol Sci 2021; 22:ijms22094413. [PMID: 33922534 PMCID: PMC8122935 DOI: 10.3390/ijms22094413] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/12/2021] [Accepted: 04/20/2021] [Indexed: 12/20/2022] Open
Abstract
Connexins are a family of transmembrane proteins that play a key role in cardiac physiology. Gap junctional channels put into contact the cytoplasms of connected cardiomyocytes, allowing the existence of electrical coupling. However, in addition to this fundamental role, connexins are also involved in cardiomyocyte death and survival. Thus, chemical coupling through gap junctions plays a key role in the spreading of injury between connected cells. Moreover, in addition to their involvement in cell-to-cell communication, mounting evidence indicates that connexins have additional gap junction-independent functions. Opening of unopposed hemichannels, located at the lateral surface of cardiomyocytes, may compromise cell homeostasis and may be involved in ischemia/reperfusion injury. In addition, connexins located at non-canonical cell structures, including mitochondria and the nucleus, have been demonstrated to be involved in cardioprotection and in regulation of cell growth and differentiation. In this review, we will provide, first, an overview on connexin biology, including their synthesis and degradation, their regulation and their interactions. Then, we will conduct an in-depth examination of the role of connexins in cardiac pathophysiology, including new findings regarding their involvement in myocardial ischemia/reperfusion injury, cardiac fibrosis, gene transcription or signaling regulation.
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12
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Talaverón R, Matarredona ER, Herrera A, Medina JM, Tabernero A. Connexin43 Region 266-283, via Src Inhibition, Reduces Neural Progenitor Cell Proliferation Promoted by EGF and FGF-2 and Increases Astrocytic Differentiation. Int J Mol Sci 2020; 21:ijms21228852. [PMID: 33238452 PMCID: PMC7700635 DOI: 10.3390/ijms21228852] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 11/20/2020] [Accepted: 11/20/2020] [Indexed: 12/13/2022] Open
Abstract
Neural progenitor cells (NPCs) are self-renewing cells that give rise to the major cells in the nervous system and are considered to be the possible cell of origin of glioblastoma. The gap junction protein connexin43 (Cx43) is expressed by NPCs, exerting channel-dependent and -independent roles. We focused on one property of Cx43—its ability to inhibit Src, a key protein in brain development and oncogenesis. Because Src inhibition is carried out by the sequence 266–283 of the intracellular C terminus in Cx43, we used a cell-penetrating peptide containing this sequence, TAT-Cx43266–283, to explore its effects on postnatal subventricular zone NPCs. Our results show that TAT-Cx43266–283 inhibited Src activity and reduced NPC proliferation and survival promoted by epidermal growth factor (EGF) and fibroblast growth factor-2 (FGF-2). In differentiation conditions, TAT-Cx43266–283 increased astrocyte differentiation at the expense of neuronal differentiation, which coincided with a reduction in Src activity and β-catenin expression. We propose that Cx43, through the region 266–283, reduces Src activity, leading to disruption of EGF and FGF-2 signaling and to down-regulation of β-catenin with effects on proliferation and differentiation. Our data indicate that the inhibition of Src might contribute to the complex role of Cx43 in NPCs and open new opportunities for further research in gliomagenesis.
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Affiliation(s)
- Rocío Talaverón
- Instituto de Neurociencias de Castilla y León (INCYL), Universidad de Salamanca, 37007 Salamanca, Spain; (R.T.); (J.M.M.)
| | | | - Alejandro Herrera
- Departamento de Fisiología, Universidad de Sevilla, 41012 Sevilla, Spain; (E.R.M.); (A.H.)
| | - José M. Medina
- Instituto de Neurociencias de Castilla y León (INCYL), Universidad de Salamanca, 37007 Salamanca, Spain; (R.T.); (J.M.M.)
| | - Arantxa Tabernero
- Instituto de Neurociencias de Castilla y León (INCYL), Universidad de Salamanca, 37007 Salamanca, Spain; (R.T.); (J.M.M.)
- Correspondence: ; Tel.: +34-923-29-45-00 (ext. 5311)
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Dilger N, Neehus AL, Grieger K, Hoffmann A, Menssen M, Ngezahayo A. Gap Junction Dependent Cell Communication Is Modulated During Transdifferentiation of Mesenchymal Stem/Stromal Cells Towards Neuron-Like Cells. Front Cell Dev Biol 2020; 8:869. [PMID: 32984345 PMCID: PMC7487424 DOI: 10.3389/fcell.2020.00869] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 08/11/2020] [Indexed: 12/22/2022] Open
Abstract
In vitro transdifferentiation of patient-derived mesenchymal stem/stromal cells (MSCs) into neurons is of special interest for treatment of neurodegenerative diseases. Although there are encouraging studies, little is known about physiological modulations during this transdifferentiation process. Here, we focus on the analysis of gap junction dependent cell-cell communication and the expression pattern of gap junction-building connexins during small molecule-induced neuronal transdifferentiation of human bone marrow-derived MSCs. During this process, the MSC markers CD73, CD90, CD105, and CD166 were downregulated while the neuronal marker Tuj1 was upregulated. Moreover, the differentiation protocol used in the present study changed the cellular morphology and physiology. The MSCs evolved from a fibroblastoid morphology towards a neuronal shape with round cell bodies and neurite-like processes. Moreover, depolarization evoked action potentials in the transdifferentiated cells. MSCs expressed mRNAs encoding Cx43 and Cx45 as well as trace levels of Cx26, Cx37- and Cx40 and allowed transfer of microinjected Lucifer yellow. The differentiation protocol increased levels of Cx26 (mRNA and protein) and decreased Cx43 (mRNA and protein) while reducing the dye transfer. Cx36 mRNA was nearly undetectable in all cells regardless of treatment. Treatment of the cells with the gap junction coupling inhibitor carbenoxolone (CBX) only modestly altered connexin mRNA levels and had little effect on neuronal differentiation. Our study indicates that the small molecule-based differentiation protocol generates immature neuron-like cells from MSCs. This might be potentially interesting for elucidating physiological modifications and mechanisms in MSCs during the initial steps of differentiation towards a neuronal lineage.
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Affiliation(s)
- Nadine Dilger
- Department of Cell Physiology and Biophysics, Institute of Cell Biology and Biophysics, Leibniz University Hannover, Hanover, Germany
| | - Anna-Lena Neehus
- Department of Cell Physiology and Biophysics, Institute of Cell Biology and Biophysics, Leibniz University Hannover, Hanover, Germany.,Institute of Experimental Hematology, REBIRTH Research Center for Translational and Regenerative Medicine, Hannover Medical School (MHH), Hanover, Germany
| | - Klaudia Grieger
- Department of Cell Physiology and Biophysics, Institute of Cell Biology and Biophysics, Leibniz University Hannover, Hanover, Germany
| | - Andrea Hoffmann
- Graded Implants and Regenerative Strategies, Department of Orthopedic Surgery, Hannover Medical School, Hanover, Germany.,Lower Saxony Centre for Biomedical Engineering, Implant Research and Development (NIFE), Hanover, Germany
| | - Max Menssen
- Department of Biostatistics, Institute of Cell Biology and Biophysics, Leibniz University Hannover, Hanover, Germany
| | - Anaclet Ngezahayo
- Department of Cell Physiology and Biophysics, Institute of Cell Biology and Biophysics, Leibniz University Hannover, Hanover, Germany.,Center for Systems Neuroscience, University of Veterinary Medicine Hannover, Hanover, Germany
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14
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Van Campenhout R, Cooreman A, Leroy K, Rusiecka OM, Van Brantegem P, Annaert P, Muyldermans S, Devoogdt N, Cogliati B, Kwak BR, Vinken M. Non-canonical roles of connexins. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2020; 153:35-41. [PMID: 32220599 DOI: 10.1016/j.pbiomolbio.2020.03.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 03/06/2020] [Accepted: 03/16/2020] [Indexed: 12/12/2022]
Abstract
Gap junctions mediate cellular communication and homeostasis by controlling the intercellular exchange of small and hydrophilic molecules and ions. Gap junction channels are formed by the docking of 2 hemichannels of adjacent cells, which in turn are composed of 6 connexin subunits. Connexin proteins as such can also control the cellular life cycle independent of their channel activities. This has been most demonstrated in the context of cell growth and cell death. Different mechanisms are involved mainly related to direct interaction with cell growth or cell death regulators, but also implying effects on the expression of cell growth and cell death regulators. The present paper focuses on these atypical roles of connexin proteins.
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Affiliation(s)
- Raf Van Campenhout
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Axelle Cooreman
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Kaat Leroy
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Olga M Rusiecka
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
| | - Pieter Van Brantegem
- Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Pieter Annaert
- Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Serge Muyldermans
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Nick Devoogdt
- In Vivo Cellular and Molecular Imaging Laboratory, Vrije Universiteit Brussel, Brussels, Belgium
| | - Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
| | - Brenda R Kwak
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium.
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15
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Kocovic DM, Limaye PV, Colburn LCH, Singh MB, Milosevic MM, Tadic J, Petronijevic M, Vrzic-Petronijevic S, Andjus PR, Antic SD. Cadmium versus Lanthanum Effects on Spontaneous Electrical Activity and Expression of Connexin Isoforms Cx26, Cx36, and Cx45 in the Human Fetal Cortex. Cereb Cortex 2020; 30:1244-1259. [PMID: 31408166 PMCID: PMC7132928 DOI: 10.1093/cercor/bhz163] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 06/25/2019] [Accepted: 06/25/2019] [Indexed: 12/29/2022] Open
Abstract
Electrical activity is important for brain development. In brain slices, human subplate neurons exhibit spontaneous electrical activity that is highly sensitive to lanthanum. Based on the results of pharmacological experiments in human fetal tissue, we hypothesized that hemichannel-forming connexin (Cx) isoforms 26, 36, and 45 would be expressed on neurons in the subplate (SP) zone. RNA sequencing of dissected human cortical mantles at ages of 17-23 gestational weeks revealed that Cx45 has the highest expression, followed by Cx36 and Cx26. The levels of Cx and pannexin expression between male and female fetal cortices were not significantly different. Immunohistochemical analysis detected Cx45- and Cx26-expressing neurons in the upper segment of the SP zone. Cx45 was present on the cell bodies of human SP neurons, while Cx26 was found on both cell bodies and dendrites. Cx45, Cx36, and Cx26 were strongly expressed in the cortical plate, where newborn migrating neurons line up to form cortical layers. New information about the expression of 3 "neuronal" Cx isoforms in each cortical layer/zone (e.g., SP, cortical plate) and pharmacological data with cadmium and lanthanum may improve our understanding of the cellular mechanisms underlying neuronal development in human fetuses and potential vulnerabilities.
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Affiliation(s)
- Dusica M Kocovic
- Faculty of Biology, University of Belgrade, Belgrade 11000, Serbia
| | - Pallavi V Limaye
- Institute for Systems Genomics, Stem Cell Institute, Department of Neuroscience, UConn Health, Farmington, CT 06030, USA
| | - Lauren C H Colburn
- Institute for Systems Genomics, Stem Cell Institute, Department of Neuroscience, UConn Health, Farmington, CT 06030, USA
| | - Mandakini B Singh
- Institute for Systems Genomics, Stem Cell Institute, Department of Neuroscience, UConn Health, Farmington, CT 06030, USA
| | - Milena M Milosevic
- Faculty of Biology, University of Belgrade, Belgrade 11000, Serbia
- Institute for Systems Genomics, Stem Cell Institute, Department of Neuroscience, UConn Health, Farmington, CT 06030, USA
| | - Jasmina Tadic
- Faculty of Medicine, University of Belgrade, Belgrade 11000, Serbia
| | | | | | - Pavle R Andjus
- Faculty of Biology, University of Belgrade, Belgrade 11000, Serbia
| | - Srdjan D Antic
- Institute for Systems Genomics, Stem Cell Institute, Department of Neuroscience, UConn Health, Farmington, CT 06030, USA
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16
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Hou X, Khan MRA, Turmaine M, Thrasivoulou C, Becker DL, Ahmed A. Wnt signaling regulates cytosolic translocation of connexin 43. Am J Physiol Regul Integr Comp Physiol 2019; 317:R248-R261. [DOI: 10.1152/ajpregu.00268.2018] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The availability of intracellular, stabilized β-catenin, a transcription factor coactivator, is tightly regulated; β-catenin is translocated into the nucleus in response to Wnt ligand binding to its cell membrane receptors. Here we show that Wnt signal activation in mammalian cells activates intracellular mobilization of connexin 43 (Cx43), which belongs to a gap junction protein family, a new target protein in response to extracellular Wnt signal activation. Transmission electron microscopy showed that the nuclear localization of Cx43 was increased by 8- to 10-fold in Wnt5A- and 9B-treated cells compared with controls; this Wnt-induced increase was negated in the cells where Cx43 and β-catenin were knocked down using shRNA. There was a significant ( P < 0.001) and concomitant depletion of the cell membrane and cytosolic signal of Cx43 in Wnt-treated cells with an increase in the nuclear signal for Cx43; this was more obvious in cells where β-catenin was knocked down using shRNA. Conversely, Cx43 knockdown resulted in increased β-catenin in the nucleus in the absence of Wnt activation. Coimmunoprecipitation of Cx43 and β-catenin proteins with a casein kinase (CKIδ) antibody showed that Cx43 interacts with β-catenin and may form part of the so-called destruction complex. Functionally, Wnt activation increased the rate of wound reepithelization in rat skin in vivo.
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Affiliation(s)
- Xiaoming Hou
- Prostate Cancer Research Centre, Division of Surgery, University College London, London, United Kingdom
- Research Department of Cell and Developmental Biology, The Centre for Cell and Molecular Dynamics, University College London, London, United Kingdom
| | - Mohammad R. A. Khan
- Prostate Cancer Research Centre at the Centre for Stem Cells and Regenerative Medicine, King's College London, Guy's Hospital, London, United Kingdom
| | - Mark Turmaine
- Division of Biosciences, University College London, London, United Kingdom
| | - Christopher Thrasivoulou
- Research Department of Cell and Developmental Biology, The Centre for Cell and Molecular Dynamics, University College London, London, United Kingdom
| | - David L Becker
- Research Department of Cell and Developmental Biology, The Centre for Cell and Molecular Dynamics, University College London, London, United Kingdom
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
- Institute of Medical Biology, A*STAR, Singapore
| | - Aamir Ahmed
- Prostate Cancer Research Centre, Division of Surgery, University College London, London, United Kingdom
- Prostate Cancer Research Centre at the Centre for Stem Cells and Regenerative Medicine, King's College London, Guy's Hospital, London, United Kingdom
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17
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Martins-Marques T, Ribeiro-Rodrigues T, Batista-Almeida D, Aasen T, Kwak BR, Girao H. Biological Functions of Connexin43 Beyond Intercellular Communication. Trends Cell Biol 2019; 29:835-847. [PMID: 31358412 DOI: 10.1016/j.tcb.2019.07.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 06/27/2019] [Accepted: 07/01/2019] [Indexed: 12/13/2022]
Abstract
Connexin43 (Cx43) is commonly associated with direct cell-cell communication through gap junctions (GJs). However, recent groundbreaking studies have challenged this dogma, implicating Cx43 in other biological processes, such as transcription, metabolism, autophagy, and ion channel trafficking. How Cx43 participates in these processes remains largely unknown, although its high turnover rate, capacity to bind to myriad proteins, and the discovery of truncated isoforms of Cx43, ascribe to this protein unanticipated roles in chief processes that require fine-tuned regulation. Accordingly, Cx43 can be regarded as a central integrative hub to which diverse cues converge to be processed in a concerted manner. In this review, we examine the noncanonical roles of Cx43 and discuss the implications of these functions in human diseases and future therapeutic strategies.
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Affiliation(s)
- Tania Martins-Marques
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal; CNC.IBILI, University of Coimbra, Portugal
| | - Teresa Ribeiro-Rodrigues
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal; CNC.IBILI, University of Coimbra, Portugal
| | - Daniela Batista-Almeida
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal; CNC.IBILI, University of Coimbra, Portugal
| | - Trond Aasen
- Translational Molecular Pathology, Vall d'Hebron Institute of Research (VHIR), Autonomous University of Barcelona, CIBERONC, Barcelona, Spain
| | - Brenda R Kwak
- Department of Pathology and Immunology, University of Geneva, CH-1211 Geneva, Switzerland
| | - Henrique Girao
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal; CNC.IBILI, University of Coimbra, Portugal.
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18
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Gouesse RJ, Lavoie M, Dianati E, Wade M, Hales B, Robaire B, Plante I. Gestational and Lactational Exposure to an Environmentally-relevant Mixture of Brominated Flame Retardants Down-regulates Junctional Proteins, Thyroid Hormone Receptor α1 Expression and the Proliferation-Apoptosis Balance in Mammary Glands Post Puberty. Toxicol Sci 2019; 171:13-31. [PMID: 31241157 PMCID: PMC6735962 DOI: 10.1093/toxsci/kfz147] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 06/11/2019] [Accepted: 06/11/2019] [Indexed: 12/21/2022] Open
Abstract
Mammary gland development requires hormonal regulation during puberty, pregnancy and lactation. Brominated flame retardants (BFRs) are endocrine disruptors; they are added to consumer products to satisfy flammability standards. Previously, we showed that gestational and lactational exposure to an environmentally-relevant mixture of BFRs disrupts proteins of the adherens junctions in rat dam mammary glands at weaning. Here, we hypothesize that perinatal exposure to the same BFR mixture also disrupts junctional proteins and signaling pathways controlling mammary gland development in pups. Dams were exposed through diet to a BFR mixture based on the substances in house dust; doses of the mixture used were 0, 0.06, 20 or 60 mg/kg/day. Dams were exposed continuously beginning prior to mating until pups' weaning; female offspring were euthanized on postnatal day (PND) 21, 46 and 208. The lowest dose of BFRs significantly down-regulated adherens junction proteins, E-cadherin and β-catenin, and the gap junction protein p-Cx43, as well as thyroid hormone receptor alpha1 protein at PND 46. No effects were observed on estrogen or progesterone receptors. The low dose also resulted in a decrease in cleaved-caspase 3, a downward trend in PARP levels, proteins involved in apoptosis, and an upward trend in PCNA, a marker of proliferation. No effects were observed on ductal elongation or on the numbers of terminal end buds. Together, our results indicate that gestational and lactational exposure to an environmentally-relevant mixture of BFRs disrupts cell-cell interactions, thyroid hormone homeostasis and the proliferation-apoptosis balance at PND 46, a critical stage for mammary gland development.
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Affiliation(s)
| | - Mélanie Lavoie
- INRS, Centre Armand-Frappier Santé Bioscience, Laval, QC, Canada
| | - Elham Dianati
- INRS, Centre Armand-Frappier Santé Bioscience, Laval, QC, Canada
| | - Mike Wade
- Health Canada, Environmental Health Science and Research Bureau, Ottawa, ON, Canada
| | - Barbara Hales
- McGill University, Faculty of Medicine, Department of Pharmacology & Therapeutics, Montreal, QC, Canada
| | - Bernard Robaire
- McGill University, Faculty of Medicine, Department of Pharmacology & Therapeutics, Montreal, QC, Canada.,McGill University, Faculty of Medicine, Department of Obstetrics & Gynecology, Montreal, QC, Canada
| | - Isabelle Plante
- INRS, Centre Armand-Frappier Santé Bioscience, Laval, QC, Canada
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β-catenin aggregation in models of ALS motor neurons: GSK3β inhibition effect and neuronal differentiation. Neurobiol Dis 2019; 130:104497. [PMID: 31176720 DOI: 10.1016/j.nbd.2019.104497] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Revised: 05/26/2019] [Accepted: 06/05/2019] [Indexed: 02/06/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by motor neuron death. A 20% of familial ALS cases are associated with mutations in the gene coding for superoxide dismutase 1 (SOD1). The accumulation of abnormal aggregates of different proteins is a common feature in motor neurons of patients and transgenic ALS mice models, which are thought to contribute to disease pathogenesis. Developmental morphogens, such as the Wnt family, regulate numerous features of neuronal physiology in the adult brain and have been implicated in neurodegeneration. β-catenin is a central mediator of both, Wnt signaling activity and cell-cell interactions. We previously reported that the expression of mutant SOD1 in the NSC34 motor neuron cell line decreases basal Wnt pathway activity, which correlates with cytosolic β-catenin accumulation and impaired neuronal differentiation. In this work, we aimed a deeper characterization of β-catenin distribution in models of ALS motor neurons. We observed extensive accumulation of β-catenin supramolecular structures in motor neuron somas of pre-symptomatic mutant SOD1 mice. In cell-cell appositional zones of NSC34 cells expressing mutant SOD1, β-catenin displays a reduced co-distribution with E-cadherin accompanied by an increased association with the gap junction protein Connexin-43; these findings correlate with impaired intercellular adhesion and exacerbated cell coupling. Remarkably, pharmacological inhibition of the glycogen synthase kinase-3β (GSK3β) in both NSC34 cell lines reverted both, β-catenin aggregation and the adverse effects of mutant SOD1 expression on neuronal differentiation. Our findings suggest that early defects in β-catenin distribution could be an underlying factor affecting the onset of neurodegeneration in familial ALS.
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20
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Fostok SF, El-Sibai M, El-Sabban M, Talhouk RS. Gap Junctions and Wnt Signaling in the Mammary Gland: a Cross-Talk? J Mammary Gland Biol Neoplasia 2019; 24:17-38. [PMID: 30194659 DOI: 10.1007/s10911-018-9411-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 09/03/2018] [Indexed: 12/21/2022] Open
Abstract
Connexins (Cxs), the building blocks of gap junctions (GJs), exhibit spatiotemporal patterns of expression and regulate the development and differentiation of the mammary gland, acting via channel-dependent and channel-independent mechanisms. Impaired Cx expression and localization are reported in breast cancer, suggesting a tumor suppressive role for Cxs. The signaling events that mediate the role of GJs in the development and tumorigenesis of the mammary gland remain poorly identified. The Wnt pathways, encompassing the canonical or the Wnt/β-catenin pathway and the noncanonical β-catenin-independent pathway, also play important roles in those processes. Indeed, aberrant Wnt signaling is associated with breast cancer. Despite the coincident roles of Cxs and Wnt pathways, the cross-talk in the breast tissue is poorly defined, although this is reported in a number of other tissues. Our previous studies revealed a channel-independent role for Cx43 in inducing differentiation or suppressing tumorigenesis of mammary epithelial cells by acting as a negative regulator of the Wnt/β-catenin pathway. Here, we provide a brief overview of mammary gland development, with emphasis on the role of Cxs in development and tumorigenesis of this tissue. We also discuss the role of Wnt signaling in similar contexts, and review the literature illustrating interplay between Cxs and Wnt pathways.
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Affiliation(s)
- Sabreen F Fostok
- Department of Biology, Faculty of Arts and Sciences, American University of Beirut (AUB), P.O. Box: 11-0236, Beirut, Lebanon
| | - Mirvat El-Sibai
- Department of Natural Sciences, School of Arts and Sciences, Lebanese American University (LAU), Beirut, Lebanon
| | - Marwan El-Sabban
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut (AUB), Beirut, Lebanon
| | - Rabih S Talhouk
- Department of Biology, Faculty of Arts and Sciences, American University of Beirut (AUB), P.O. Box: 11-0236, Beirut, Lebanon.
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21
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Spagnol G, Trease AJ, Zheng L, Gutierrez M, Basu I, Sarmiento C, Moore G, Cervantes M, Sorgen PL. Connexin43 Carboxyl-Terminal Domain Directly Interacts with β-Catenin. Int J Mol Sci 2018; 19:ijms19061562. [PMID: 29882937 PMCID: PMC6032326 DOI: 10.3390/ijms19061562] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 05/18/2018] [Accepted: 05/22/2018] [Indexed: 12/13/2022] Open
Abstract
Activation of Wnt signaling induces Connexin43 (Cx43) expression via the transcriptional activity of β-catenin, and results in the enhanced accumulation of the Cx43 protein and the formation of gap junction channels. In response to Wnt signaling, β-catenin co-localizes with the Cx43 protein itself as part of a complex at the gap junction plaque. Work from several labs have also shown indirect evidence of this interaction via reciprocal co-immunoprecipitation. Our goal for the current study was to identify whether β-catenin directly interacts with Cx43, and if so, the location of that direct interaction. Identifying residues involved in direct protein⁻protein interaction is of importance when they are correlated to the phosphorylation of Cx43, as phosphorylation can modify the binding affinities of Cx43 regulatory protein partners. Therefore, combining the location of a protein partner interaction on Cx43 along with the phosphorylation pattern under different homeostatic and pathological conditions will be crucial information for any potential therapeutic intervention. Here, we identified that β-catenin directly interacts with the Cx43 carboxyl-terminal domain, and that this interaction would be inhibited by the Src phosphorylation of Cx43CT residues Y265 and Y313.
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Affiliation(s)
- Gaelle Spagnol
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Andrew J Trease
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Li Zheng
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Mirtha Gutierrez
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Ishika Basu
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Cleofes Sarmiento
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Gabriella Moore
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Matthew Cervantes
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Paul L Sorgen
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
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22
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Sorgen PL, Trease AJ, Spagnol G, Delmar M, Nielsen MS. Protein⁻Protein Interactions with Connexin 43: Regulation and Function. Int J Mol Sci 2018; 19:E1428. [PMID: 29748463 PMCID: PMC5983787 DOI: 10.3390/ijms19051428] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 05/07/2018] [Accepted: 05/08/2018] [Indexed: 12/11/2022] Open
Abstract
Connexins are integral membrane building blocks that form gap junctions, enabling direct cytoplasmic exchange of ions and low-molecular-mass metabolites between adjacent cells. In the heart, gap junctions mediate the propagation of cardiac action potentials and the maintenance of a regular beating rhythm. A number of connexin interacting proteins have been described and are known gap junction regulators either through direct effects (e.g., kinases) or the formation of larger multifunctional complexes (e.g., cytoskeleton scaffold proteins). Most connexin partners can be categorized as either proteins promoting coupling by stimulating forward trafficking and channel opening or inhibiting coupling by inducing channel closure, internalization, and degradation. While some interactions have only been implied through co-localization using immunohistochemistry, others have been confirmed by biophysical methods that allow detection of a direct interaction. Our understanding of these interactions is, by far, most well developed for connexin 43 (Cx43) and the scope of this review is to summarize our current knowledge of their functional and regulatory roles. The significance of these interactions is further exemplified by demonstrating their importance at the intercalated disc, a major hub for Cx43 regulation and Cx43 mediated effects.
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Affiliation(s)
- Paul L Sorgen
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Andrew J Trease
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Gaelle Spagnol
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Mario Delmar
- Leon H Charney Division of Cardiology, NYU School of Medicine, New York, NY 10016, USA.
| | - Morten S Nielsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark.
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23
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Pozhilenkova EA, Lopatina OL, Komleva YK, Salmin VV, Salmina AB. Blood-brain barrier-supported neurogenesis in healthy and diseased brain. Rev Neurosci 2018; 28:397-415. [PMID: 28195555 DOI: 10.1515/revneuro-2016-0071] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 12/23/2016] [Indexed: 12/23/2022]
Abstract
Adult neurogenesis is one of the most important mechanisms contributing to brain development, learning, and memory. Alterations in neurogenesis underlie a wide spectrum of brain diseases. Neurogenesis takes place in highly specialized neurogenic niches. The concept of neurogenic niches is becoming widely accepted due to growing evidence of the important role of the microenvironment established in the close vicinity to stem cells in order to provide adequate control of cell proliferation, differentiation, and apoptosis. Neurogenic niches represent the platform for tight integration of neurogenesis and angiogenesis supported by specific properties of cerebral microvessel endothelial cells contributing to establishment of partially compromised blood-brain barrier (BBB) for the adjustment of local conditions to the current metabolic needs of stem and progenitor cells. Here, we review up-to-date data on microvascular dynamics in activity-dependent neurogenesis, specific properties of BBB in neurogenic niches, endothelial-driven mechanisms of clonogenic activity, and future perspectives for reconstructing the neurogenic niches in vitro.
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24
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Zhang X, Zhao F, Zhao JF, Fu HY, Huang XJ, Lv BD. PDGF-mediated PI3K/AKT/β-catenin signaling regulates gap junctions in corpus cavernosum smooth muscle cells. Exp Cell Res 2017; 362:252-259. [PMID: 29174980 DOI: 10.1016/j.yexcr.2017.11.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 11/17/2017] [Accepted: 11/18/2017] [Indexed: 02/06/2023]
Abstract
Erectile dysfunction (ED) is the most common sexual disorder that men report to healthcare providers. Gap junctions (GJs) are thought to be responsible for synchronous shrinkage of corpus cavernosum smooth muscle cells (CCSMCs), and play thus an important role in the maintenance of an erection. Hypoxia has been suggested as a pathological mechanism underlying ED. Here we demonstrate that hypoxia increased the expression of platelet-derived growth factor (PDGF) and the main GJ component connexin (Cx)43 in CCSMCs. Inhibiting PDGF receptor (PDGFR) activity decreased Cx43 expression. Treatment with different concentrations of PDGF increased the levels of phosphorylated protein kinase B (AKT), β-catenin, and Cx43, whereas inhibition of PDGFR or activation of phosphatidylinositol 3 kinase (PI3K)/AKT signaling altered β-catenin and Cx43 expression. Meanwhile, silencing β-catenin resulted in the downregulation of Cx43. These results demonstrate that PDGF secretion by CCSMCs and vascular endothelial cells is enhanced under hypoxic conditions, leading to increased Cx43 expression through PI3K/AKT/β-catenin signaling and ultimately affecting GJ function in ED. Thus, targeting this pathway is a potential therapeutic strategy for the treatment of ED.
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Affiliation(s)
- Xiang Zhang
- The Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, China
| | - Fan Zhao
- The Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, China
| | - Jian-Feng Zhao
- Department of Urology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Hui-Ying Fu
- The Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, China; Andrology Laboratory on Integration of Chinese and Western Medicine, Zhejiang Provincial Key Laboratory of Traditional Chinese Medicine, Hangzhou, China
| | - Xiao-Jun Huang
- Department of Urology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Bo-Dong Lv
- Department of Urology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China; Andrology Laboratory on Integration of Chinese and Western Medicine, Zhejiang Provincial Key Laboratory of Traditional Chinese Medicine, Hangzhou, China.
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25
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Morioka N, Fujii S, Kondo S, Zhang FF, Miyauchi K, Nakamura Y, Hisaoka-Nakashima K, Nakata Y. Downregulation of spinal astrocytic connexin43 leads to upregulation of interleukin-6 and cyclooxygenase-2 and mechanical hypersensitivity in mice. Glia 2017; 66:428-444. [DOI: 10.1002/glia.23255] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 10/13/2017] [Accepted: 10/13/2017] [Indexed: 12/19/2022]
Affiliation(s)
- Norimitsu Morioka
- Department of Pharmacology; Hiroshima University Graduate School of Biomedical & Health Sciences, 1-2-3 Kasumi; Minami-ku Hiroshima 734-8553 Japan
| | - Shiori Fujii
- Department of Pharmacology; Hiroshima University Graduate School of Biomedical & Health Sciences, 1-2-3 Kasumi; Minami-ku Hiroshima 734-8553 Japan
| | - Syun Kondo
- Department of Pharmacology; Hiroshima University Graduate School of Biomedical & Health Sciences, 1-2-3 Kasumi; Minami-ku Hiroshima 734-8553 Japan
| | - Fang Fang Zhang
- Department of Pharmacology; Hiroshima University Graduate School of Biomedical & Health Sciences, 1-2-3 Kasumi; Minami-ku Hiroshima 734-8553 Japan
- Institute of Pharmacology, Taishan Medical University, 619 Changcheng Road; Taian Shandong 271016 China
| | - Kazuki Miyauchi
- Department of Pharmacology; Hiroshima University Graduate School of Biomedical & Health Sciences, 1-2-3 Kasumi; Minami-ku Hiroshima 734-8553 Japan
| | - Yoki Nakamura
- Department of Pharmacology; Hiroshima University Graduate School of Biomedical & Health Sciences, 1-2-3 Kasumi; Minami-ku Hiroshima 734-8553 Japan
- Cellular Pathobiology Section, Integrative Neuroscience Research Branch, National Institute on Drug Abuse IRP, Triad Suite 3305, 333 Cassell Drive; Baltimore MD 21224
| | - Kazue Hisaoka-Nakashima
- Department of Pharmacology; Hiroshima University Graduate School of Biomedical & Health Sciences, 1-2-3 Kasumi; Minami-ku Hiroshima 734-8553 Japan
| | - Yoshihiro Nakata
- Department of Pharmacology; Hiroshima University Graduate School of Biomedical & Health Sciences, 1-2-3 Kasumi; Minami-ku Hiroshima 734-8553 Japan
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26
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Leithe E, Mesnil M, Aasen T. The connexin 43 C-terminus: A tail of many tales. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1860:48-64. [PMID: 28526583 DOI: 10.1016/j.bbamem.2017.05.008] [Citation(s) in RCA: 137] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 05/10/2017] [Accepted: 05/12/2017] [Indexed: 10/19/2022]
Abstract
Connexins are chordate gap junction channel proteins that, by enabling direct communication between the cytosols of adjacent cells, create a unique cell signalling network. Gap junctional intercellular communication (GJIC) has important roles in controlling cell growth and differentiation and in tissue development and homeostasis. Moreover, several non-canonical connexin functions unrelated to GJIC have been discovered. Of the 21 members of the human connexin family, connexin 43 (Cx43) is the most widely expressed and studied. The long cytosolic C-terminus (CT) of Cx43 is subject to extensive post-translational modifications that modulate its intracellular trafficking and gap junction channel gating. Moreover, the Cx43 CT contains multiple domains involved in protein interactions that permit crosstalk between Cx43 and cytoskeletal and regulatory proteins. These domains endow Cx43 with the capacity to affect cell growth and differentiation independently of GJIC. Here, we review the current understanding of the regulation and unique functions of the Cx43 CT, both as an essential component of full-length Cx43 and as an independent signalling hub. We highlight the complex regulatory and signalling networks controlled by the Cx43 CT, including the extensive protein interactome that underlies both gap junction channel-dependent and -independent functions. We discuss these data in relation to the recent discovery of the direct translation of specific truncated forms of Cx43. This article is part of a Special Issue entitled: Gap Junction Proteins edited by Jean Claude Herve.
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Affiliation(s)
- Edward Leithe
- Department of Molecular Oncology, Institute for Cancer Research, University of Oslo, NO-0424 Oslo, Norway; Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, NO-0424 Oslo, Norway
| | - Marc Mesnil
- STIM Laboratory ERL 7368 CNRS - Faculté des Sciences Fondamentales et Appliquées, Université de Poitiers, Poitiers 86073, France
| | - Trond Aasen
- Translational Molecular Pathology, Vall d'Hebron Institute of Research (VHIR), Autonomous University of Barcelona, CIBERONC, 08035 Barcelona, Spain.
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27
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Laguesse S, Close P, Van Hees L, Chariot A, Malgrange B, Nguyen L. Loss of Elp3 Impairs the Acetylation and Distribution of Connexin-43 in the Developing Cerebral Cortex. Front Cell Neurosci 2017; 11:122. [PMID: 28507509 PMCID: PMC5410572 DOI: 10.3389/fncel.2017.00122] [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: 01/10/2017] [Accepted: 04/12/2017] [Indexed: 12/19/2022] Open
Abstract
The Elongator complex is required for proper development of the cerebral cortex. Interfering with its activity in vivo delays the migration of postmitotic projection neurons, at least through a defective α-tubulin acetylation. However, this complex is already expressed by cortical progenitors where it may regulate the early steps of migration by targeting additional proteins. Here we report that connexin-43 (Cx43), which is strongly expressed by cortical progenitors and whose depletion impairs projection neuron migration, requires Elongator expression for its proper acetylation. Indeed, we show that Cx43 acetylation is reduced in the cortex of Elp3cKO embryos, as well as in a neuroblastoma cell line depleted of Elp1 expression, suggesting that Cx43 acetylation requires Elongator in different cellular contexts. Moreover, we show that histones deacetylase 6 (HDAC6) is a deacetylase of Cx43. Finally, we report that acetylation of Cx43 regulates its membrane distribution in apical progenitors of the cerebral cortex.
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Affiliation(s)
- Sophie Laguesse
- GIGA-Neurosciences, University of LiègeLiège, Belgium.,Interdisciplinary Cluster for Applied Genoproteomics (GIGA-R), University of LiègeLiège, Belgium
| | - Pierre Close
- Interdisciplinary Cluster for Applied Genoproteomics (GIGA-R), University of LiègeLiège, Belgium.,GIGA-Molecular Biology of Diseases, University of LiègeLiège, Belgium
| | - Laura Van Hees
- GIGA-Neurosciences, University of LiègeLiège, Belgium.,Interdisciplinary Cluster for Applied Genoproteomics (GIGA-R), University of LiègeLiège, Belgium
| | - Alain Chariot
- Interdisciplinary Cluster for Applied Genoproteomics (GIGA-R), University of LiègeLiège, Belgium.,GIGA-Molecular Biology of Diseases, University of LiègeLiège, Belgium.,Walloon Excellence in Lifesciences and Biotechnology (WELBIO)Wallonia, Belgium
| | - Brigitte Malgrange
- GIGA-Neurosciences, University of LiègeLiège, Belgium.,Interdisciplinary Cluster for Applied Genoproteomics (GIGA-R), University of LiègeLiège, Belgium
| | - Laurent Nguyen
- GIGA-Neurosciences, University of LiègeLiège, Belgium.,Interdisciplinary Cluster for Applied Genoproteomics (GIGA-R), University of LiègeLiège, Belgium
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28
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Lee GH, Jang B, Choi HS, Kim HJ, Park JH, Jeon YC, Carp RI, Kim YS, Choi EK. Upregulation of Connexin 43 Expression Via C-Jun N-Terminal Kinase Signaling in Prion Disease. J Alzheimers Dis 2016; 49:1005-19. [PMID: 26599051 DOI: 10.3233/jad-150283] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Prion infection leads to neuronal cell death, glial cell activation, and the accumulation of misfolded prion proteins. However, the altered cellular environments in animals with prion diseases are poorly understood. In the central nervous system, cells connect the cytoplasm of adjacent cells via connexin (Cx)-assembled gap junction channels to allow the direct exchange of small molecules, including ions, neurotransmitters, and signaling molecules, which regulate the activities of the connected cells. Here, we investigate the role of Cx43 in the pathogenesis of prion diseases. Upregulated Cx43 expression, which was dependent on c-Jun N-Terminal Kinase (JNK)/c-Jun signaling cascades, was found in prion-affected brain tissues and hippocampal neuronal cells. Scrapie infection-induced Cx43 formed aggregated plaques within the cytoplasmic compartments at the cell-cell interfaces. The ethidium bromide (EtBr) uptake assay and scrape-loading dye transfer assay demonstrated that increased Cx43 has functional consequences for the activity of Cx43 hemichannels. Interestingly, blockade of PrPSc accumulation reduced Cx43 expression through the inhibition of JNK signaling, indicating that PrPSc accumulation may be directly involved in JNK activation-mediated Cx43 upregulation. Overall, our findings describe a scrapie infection-mediated novel regulatory signaling pathway of Cx43 expression and may suggest a role for Cx43 in the pathogenesis of prion diseases.
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Affiliation(s)
- Geon-Hwi Lee
- Ilsong Institute of Life Science, Hallym University, Anyang, Gyeonggi-do, Republic of Korea.,Department of Biomedical Gerontology, Graduate School of Hallym University, Chuncheon, Gangwon-do, Republic of Korea
| | - Byungki Jang
- Ilsong Institute of Life Science, Hallym University, Anyang, Gyeonggi-do, Republic of Korea
| | - Hong-Seok Choi
- Ilsong Institute of Life Science, Hallym University, Anyang, Gyeonggi-do, Republic of Korea.,Department of Microbiology, College of Medicine, Hallym University, Chuncheon, Gangwon-do, Republic of Korea
| | - Hee-Jun Kim
- Ilsong Institute of Life Science, Hallym University, Anyang, Gyeonggi-do, Republic of Korea
| | - Jeong-Ho Park
- Ilsong Institute of Life Science, Hallym University, Anyang, Gyeonggi-do, Republic of Korea.,Department of Microbiology, College of Medicine, Hallym University, Chuncheon, Gangwon-do, Republic of Korea
| | - Yong-Chul Jeon
- Ilsong Institute of Life Science, Hallym University, Anyang, Gyeonggi-do, Republic of Korea
| | - Richard I Carp
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Yong-Sun Kim
- Ilsong Institute of Life Science, Hallym University, Anyang, Gyeonggi-do, Republic of Korea.,Department of Microbiology, College of Medicine, Hallym University, Chuncheon, Gangwon-do, Republic of Korea
| | - Eun-Kyoung Choi
- Ilsong Institute of Life Science, Hallym University, Anyang, Gyeonggi-do, Republic of Korea.,Department of Biomedical Gerontology, Graduate School of Hallym University, Chuncheon, Gangwon-do, Republic of Korea
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29
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Zhang Z, Li Z, Deng W, He Q, Wang Q, Shi W, Chen Q, Yang W, Spector M, Gong A, Yu J, Xu X. Ectoderm mesenchymal stem cells promote differentiation and maturation of oligodendrocyte precursor cells. Biochem Biophys Res Commun 2016; 480:727-733. [PMID: 27983986 DOI: 10.1016/j.bbrc.2016.10.115] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 10/26/2016] [Indexed: 11/24/2022]
Abstract
Many neurological diseases are closely associated with demyelination caused by pathological changes of oligodendrocytes. Although intrinsic remyelination occurs after injury, the regeneration efficiency of myelinating oligodendrocytes remains to be improved. Herein, we reported an initiative finding of employing a valuable cell source, namely neural crest-derived ectoderm mesenchymal stem cells (EMSCs), for promoting oligodendrocyte differentiation and maturation by co-culturing oligodendrocyte precursor cells (OPCs) with the EMSCs. The results demonstrated that the OPCs/EMSCs co-culture could remarkably increase the number and length of oligodendrocyte processes in comparison with the mono-cultured OPCs and non-contact OPCs/EMSCs transwell culture. Furthermore, the inhibition experiments revealed that the EMSCs-produced soluble factor Sonic hedgehog, gap junction protein connexin 43 and extracellular matrix molecule laminin accounted for the promoted OPC differentiation since inhibiting the function of anyone of the three proteins led to substantial retraction of processes and detachment of oligodendrocytes. Altogether, OPCs/EMSCs co-culture system could be a paradigmatic approach for promoting differentiation and maturation of oligodendrocytes, and EMSCs will be a promising cell source for the treatment of neurological diseases caused by oligodendrocyte death and demyelination.
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Affiliation(s)
- Zhijian Zhang
- School of Medicine, Jiangsu University, Zhenjiang, 212001, PR China; Center for Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, 212001, PR China
| | - Zhengnan Li
- School of Medicine, Jiangsu University, Zhenjiang, 212001, PR China; Center for Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, 212001, PR China
| | - Wenwen Deng
- Center for Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, 212001, PR China; Department of Pharmaceutics, School of Pharmacy, Jiangsu University, Zhenjiang, 212001, PR China
| | - Qinghua He
- Center for Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, 212001, PR China; Department of Pharmaceutics, School of Pharmacy, Jiangsu University, Zhenjiang, 212001, PR China
| | - Qiang Wang
- Center for Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, 212001, PR China; Department of Pharmaceutics, School of Pharmacy, Jiangsu University, Zhenjiang, 212001, PR China
| | - Wentao Shi
- School of Medicine, Jiangsu University, Zhenjiang, 212001, PR China
| | - Qian Chen
- School of Medicine, Jiangsu University, Zhenjiang, 212001, PR China
| | - Wenjing Yang
- School of Medicine, Jiangsu University, Zhenjiang, 212001, PR China
| | - Myron Spector
- Department of Orthopedic Surgery, Harvard Medical School, Brigham and Women's Hospital, 75 Francis St, Boston, MA, 02115, USA
| | - Aihua Gong
- School of Medicine, Jiangsu University, Zhenjiang, 212001, PR China; Center for Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, 212001, PR China
| | - Jiangnan Yu
- Center for Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, 212001, PR China; Department of Pharmaceutics, School of Pharmacy, Jiangsu University, Zhenjiang, 212001, PR China
| | - Ximing Xu
- Center for Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, 212001, PR China; Department of Pharmaceutics, School of Pharmacy, Jiangsu University, Zhenjiang, 212001, PR China.
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30
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Deubiquitinase Usp8 regulates α-synuclein clearance and modifies its toxicity in Lewy body disease. Proc Natl Acad Sci U S A 2016; 113:E4688-97. [PMID: 27444016 PMCID: PMC4987833 DOI: 10.1073/pnas.1523597113] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In Parkinson's disease, misfolded α-synuclein accumulates, often in a ubiquitinated form, in neuronal inclusions termed Lewy bodies. An important outstanding question is whether ubiquitination in Lewy bodies is directly relevant to α-synuclein trafficking or turnover and Parkinson's pathogenesis. By comparative analysis in human postmortem brains, we found that ubiquitin immunoreactivity in Lewy bodies is largely due to K63-linked ubiquitin chains and markedly reduced in the substantia nigra compared with the neocortex. The ubiquitin staining in cells with Lewy bodies inversely correlated with the content and pathological localization of the deubiquitinase Usp8. Usp8 interacted and partly colocalized with α-synuclein in endosomal membranes and, both in cells and after purification, it deubiquitinated K63-linked chains on α-synuclein. Knockdown of Usp8 in the Drosophila eye reduced α-synuclein levels and α-synuclein-induced eye toxicity. Accordingly, in human cells, Usp8 knockdown increased the lysosomal degradation of α-synuclein. In the dopaminergic neurons of the Drosophila model, unlike knockdown of other deubiquitinases, Usp8 protected from α-synuclein-induced locomotor deficits and cell loss. These findings strongly suggest that removal of K63-linked ubiquitin chains on α-synuclein by Usp8 is a critical mechanism that reduces its lysosomal degradation in dopaminergic neurons and may contribute to α-synuclein accumulation in Lewy body disease.
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31
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Abstract
Connexins and pannexins share very similar structures and functions; they also exhibit overlapping expression in many stages of neuronal development. Here, we review evidence implicating connexin- and pannexin-mediated communication in the regulation of the birth and development of neurons, specifically Cx26, Cx30, Cx32, Cx36, Cx43, Cx45, Panx1, and Panx2. We begin by dissecting the involvement of these proteins in the generation and development of new neurons in the embryonic, postnatal, and adult brain. Next we briefly outline common mechanisms employed by both pannexins and connexins in these roles, including modulation of purinergic receptor signalling and signalling nexus functions. Throughout this review we highlight developing themes as well as important gaps in knowledge to be bridged.
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Affiliation(s)
- Leigh Anne Swayne
- />Division of Medical Sciences, University of Victoria, Medical Sciences Building Rm 224, 3800 Finnerty Rd, Victoria, BC V8P5C2 Canada
| | - Steffany A. L. Bennett
- />Department of Biochemistry, Microbiology and Immunology, Neural Regeneration Laboratory, Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ON Canada
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32
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Watters AK, Rom S, Hill JD, Dematatis MK, Zhou Y, Merkel SF, Andrews AM, Cena J, Potula R, Skuba A, Son YJ, Persidsky Y, Ramirez SH. Identification and dynamic regulation of tight junction protein expression in human neural stem cells. Stem Cells Dev 2016; 24:1377-89. [PMID: 25892136 DOI: 10.1089/scd.2014.0497] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Recent reports indicate that neural stem cells (NSCs) exist in a cluster-like formation in close proximity to cerebral microvessels. Similar appearing clusters can be seen ex vivo in NSC cultures termed neurospheres. It is known that this neurosphere configuration is important for preserving stemness and a proliferative state. How NSCs form neurospheres or neuroclusters remains largely undetermined. In this study, we show that primary human NSCs express the tight junction proteins (TJPs): zonula occludens-1 (ZO-1), occludin, claudin-1, -3, -5, and -12. The relative mRNA expression was measured by quantitative polymerase chain reaction, and protein expression was confirmed by flow cytometry and immunofluorescence microscopy. Our results show that downregulation of TJPs occurs as neuronal differentiation is induced, suggesting that control of TJPs may be tied to the neuronal differentiation program. Importantly, upon specific knockdown of the accessory TJP, ZO-1, undifferentiated NSCs showed decreased levels of key stem cell markers. Taken together, our results indicate that TJPs possibly aid in maintaining the intercellular configuration of NSCs and that reduction in TJP expression consequently affects the stemness status.
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Affiliation(s)
- Andrea K Watters
- 1Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania
| | - Slava Rom
- 1Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania
| | - Jeremy D Hill
- 1Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania
| | - Marie K Dematatis
- 1Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania
| | - Yu Zhou
- 1Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania
| | - Steven F Merkel
- 1Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania
| | - Allison M Andrews
- 1Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania
| | - Jonathan Cena
- 1Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania
| | - Raghava Potula
- 1Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania.,2Center for Substance Abuse Research, Temple University School of Medicine, Philadelphia, Pennsylvania
| | - Andrew Skuba
- 3Shriners Hospitals Pediatric Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania
| | - Young-Jin Son
- 3Shriners Hospitals Pediatric Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania
| | - Yuri Persidsky
- 1Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania.,2Center for Substance Abuse Research, Temple University School of Medicine, Philadelphia, Pennsylvania
| | - Servio H Ramirez
- 1Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania.,2Center for Substance Abuse Research, Temple University School of Medicine, Philadelphia, Pennsylvania.,3Shriners Hospitals Pediatric Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania
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33
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All-Trans Retinoic Acid-Induced Deficiency of the Wnt/β-Catenin Pathway Enhances Hepatic Carcinoma Stem Cell Differentiation. PLoS One 2015; 10:e0143255. [PMID: 26571119 PMCID: PMC4646487 DOI: 10.1371/journal.pone.0143255] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 11/02/2015] [Indexed: 01/03/2023] Open
Abstract
Retinoic acid (RA) is an important biological signal that directly differentiates cells during embryonic development and tumorigenesis. However, the molecular mechanism of RA-mediated differentiation in hepatic cancer stem cells (hCSCs) is not well understood. In this study, we found that mRNA expressions of RA-biosynthesis-related dehydrogenases were highly expressed in hepatocellular carcinoma. All-trans retinoic acid (ATRA) differentiated hCSCs through inhibiting the function of β-catenin in vitro. ATRA also inhibited the function of PI3K-AKT and enhanced GSK-3β-dependent degradation of phosphorylated β-catenin. Furthermore, ATRA and β-catenin silencing both increased hCSC sensitivity to docetaxel treatment. Our results suggest that targeting β-catenin will provide extra benefits for ATRA-mediated treatment of hepatic cancer patients.
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34
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Remodeling of the intercalated disc related to aging in the mouse heart. J Cardiol 2015; 68:261-8. [PMID: 26584974 DOI: 10.1016/j.jjcc.2015.10.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 08/10/2015] [Accepted: 09/08/2015] [Indexed: 12/24/2022]
Abstract
BACKGROUND Aging is related to declined cardiac hemodynamic function. As pumping performance may be significantly related to slowed ventricular depolarization and non-synchronous contraction, we hypothesized that aging may cause dysfunction of intercalated disc (ID), which is the structure responsible for intercellular electrical communication between cardiomyocytes. METHODS Male C57BL/6J mice were used for the study at two ages: 4 and 24 months. Electrocardiographic recording was made to analyze the time of ventricular depolarization. Then mice were killed, and the hearts were harvested for examination in transmission electron microscopy (TEM) and immunofluorescence imaging. The expression of connexin 43 (Cx43), N-cadherin, and β-catenin in the myocardium of the left ventricle was evaluated using Western blotting. RESULTS In senescent mice, analysis of averaged QRS complex showed its significant prolongation. At the ultrastructural level, we found frequent disruptions of the ID (affecting 29±5% of them), mainly at the site of adherens junction, with relatively preserved desmosomal intercellular connections and diminished number of gap junctions. Western blotting revealed significantly decreased abundance of Cx43 protein in aged animals, which may cause slowed impulse propagation through the gap junctions and contribute to the observed electrocardiographic alterations. The level of RNA for Cx43 is similar between young and old animals, which suggests a post-transcriptional mechanism of Cx43 protein downregulation. CONCLUSIONS Our study shows age-related disorganization of ID, which may be responsible for slowed conduction of the depolarization wave within the heart, and supports the hypothesis of cardiac dysfunction in senescence.
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Decrock E, De Bock M, Wang N, Bultynck G, Giaume C, Naus CC, Green CR, Leybaert L. Connexin and pannexin signaling pathways, an architectural blueprint for CNS physiology and pathology? Cell Mol Life Sci 2015; 72:2823-51. [PMID: 26118660 PMCID: PMC11113968 DOI: 10.1007/s00018-015-1962-7] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 06/11/2015] [Indexed: 02/06/2023]
Abstract
The central nervous system (CNS) is composed of a highly heterogeneous population of cells. Dynamic interactions between different compartments (neuronal, glial, and vascular systems) drive CNS function and allow to integrate and process information as well as to respond accordingly. Communication within this functional unit, coined the neuro-glio-vascular unit (NGVU), typically relies on two main mechanisms: direct cell-cell coupling via gap junction channels (GJCs) and paracrine communication via the extracellular compartment, two routes to which channels composed of transmembrane connexin (Cx) or pannexin (Panx) proteins can contribute. Multiple isoforms of both protein families are present in the CNS and each CNS cell type is characterized by a unique Cx/Panx portfolio. Over the last two decades, research has uncovered a multilevel platform via which Cxs and Panxs can influence different cellular functions within a tissue: (1) Cx GJCs enable a direct cell-cell communication of small molecules, (2) Cx hemichannels and Panx channels can contribute to autocrine/paracrine signaling pathways, and (3) different structural domains of these proteins allow for channel-independent functions, such as cell-cell adhesion, interactions with the cytoskeleton, and the activation of intracellular signaling pathways. In this paper, we discuss current knowledge on their multifaceted contribution to brain development and to specific processes in the NGVU, including synaptic transmission and plasticity, glial signaling, vasomotor control, and blood-brain barrier integrity in the mature CNS. By highlighting both physiological and pathological conditions, it becomes evident that Cxs and Panxs can play a dual role in the CNS and that an accurate fine-tuning of each signaling mechanism is crucial for normal CNS physiology.
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Affiliation(s)
- Elke Decrock
- Physiology Group, Department of Basic Medical Sciences, Ghent University, De Pintelaan 185 (Block B, 3rd floor), 9000 Ghent, Belgium
| | - Marijke De Bock
- Physiology Group, Department of Basic Medical Sciences, Ghent University, De Pintelaan 185 (Block B, 3rd floor), 9000 Ghent, Belgium
| | - Nan Wang
- Physiology Group, Department of Basic Medical Sciences, Ghent University, De Pintelaan 185 (Block B, 3rd floor), 9000 Ghent, Belgium
| | - Geert Bultynck
- Laboratory of Molecular and Cellular Signalling, Department of Cellular and Molecular Medicine, KU Leuven, Louvain, Belgium
| | - Christian Giaume
- Collège de France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7241/Institut National de la Santé et de la Recherche Médicale U1050, 75231 Paris Cedex 05, France
- University Pierre et Marie
Curie, ED, N°158, 75005 Paris, France
- MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, 75005 Paris, France
| | - Christian C. Naus
- Department of Cellular and Physiological Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3 Canada
| | - Colin R. Green
- Department of Ophthalmology, The University of Auckland, Auckland, New Zealand
| | - Luc Leybaert
- Physiology Group, Department of Basic Medical Sciences, Ghent University, De Pintelaan 185 (Block B, 3rd floor), 9000 Ghent, Belgium
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