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Zhai P, Zhang H, Li Q, Yang M, Guo Y, Xing C. DNMT1-mediated NR3C1 DNA methylation enables transcription activation of connexin40 and augments angiogenesis during colorectal cancer progression. Gene 2024; 892:147887. [PMID: 37813207 DOI: 10.1016/j.gene.2023.147887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 09/12/2023] [Accepted: 10/06/2023] [Indexed: 10/11/2023]
Abstract
Colorectal cancer (CRC) continues to be a major contributor to cancer-related mortality. Connexin 40 (CX40) is one of the major gap junction proteins with the capacity in regulating cell-to-cell communication and angiogenesis. This study investigates its role in angiogenesis in CRC and explores the regulatory mechanism. Aberrant high CX40 expression was detected in tumor tissues, which was associated with a poor prognosis in CRC patients. Elevated CX40 expression was detected in CRC cell lines as well. Conditioned medium of SW620 and HT29 cell lines was used to induce angiogenesis of human umbilical vein endothelial cells (HUVECs). CX40 knockdown in CRC cells reduced angiogenesis and mobility of HUVECs and blocked CRC cell proliferation, mobility, and survival. Following bioinformatics predictions, we validated by chromatin immunoprecipitation and luciferase assays that nuclear receptor subfamily 3 group C member 1 (NR3C1), which was poorly expressed in CRC samples, suppressed CX40 transcription. The poor NR3C1 expression was attributive to DNA hypermethylation induced by DNA methyltransferase 1 (DNMT1). Restoration of NR3C1 suppressed the pro-angiogenic effect, proliferation and survival, and tumorigenic activity of CRC cells, which were, however, rescued by CX40 upregulation. Collectively, this study demonstrates that transcription activation of CX40 upon DNMT1-mediated NR3C1 DNA methylation potentiates angiogenesis in CRC.
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Affiliation(s)
- Peng Zhai
- Department of General Surgery, The Second Affiliated Hospital of Soochow University, Suzhou 215004, Jiangsu, PR China; Department of General Surgery, Fifth People's Hospital of Huai'an City, Huai'an 223300, Jiangsu, PR China
| | - Heng Zhang
- Department of General Surgery, Nanjing Lishui District People's Hospital, Zhongda Hospital Lishui Branch, Southeast University, Nanjing 211200, Jiangsu, PR China
| | - Qiang Li
- Department of General Surgery, The Second Affiliated Hospital of Soochow University, Suzhou 215004, Jiangsu, PR China; Department of Gerneral Surgery, The Second Afilliated Hospital of Xuzhou Medical University, Xuzhou 221000, Jiangsu, PR China
| | - Ming Yang
- Department of General Surgery, Fifth People's Hospital of Huai'an City, Huai'an 223300, Jiangsu, PR China
| | - Yunhu Guo
- Department of General Surgery, Fifth People's Hospital of Huai'an City, Huai'an 223300, Jiangsu, PR China
| | - Chungen Xing
- Department of General Surgery, The Second Affiliated Hospital of Soochow University, Suzhou 215004, Jiangsu, PR China.
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2
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Looker EK, Aan FJ, Hatch CJ, Hughes CC, Matter ML, Fang JS. Cx40 Suppresses Sprouting Angiogenesis In Vitro. Bioelectricity 2023; 5:307-317. [PMID: 40151625 PMCID: PMC11949415 DOI: 10.1089/bioe.2023.0034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2025] Open
Abstract
Blood vessels are highly organized and form during development through a series of complex processes that include vasculogenesis, sprouting angiogenesis, and vessel remodeling. Several gap junction proteins (termed connexins, Cx)-including Cx40 (GJA5)-are expressed in vascular endothelium early during vessel development and are critical for establishment of a healthy vasculature. However, Cx40's specific role in regulating vessel growth remains uncertain: while previous studies have shown that developmental and cancer-associated neovascularization is reduced in Cx40-knockout mice, Cx40 knockout in zebrafish embryos enhances intersegmental vessel growth. Thus, in the current study, our aim was to identify Cx40's specific role in sprouting angiogenesis. First, we used a vessel-on-a-chip microphysiological model to confirm Cx40's overall necessity for microvessel network development. Next, we used the fibrin gel bead assay-a three-dimensional in vitro model of sprouting angiogenesis-to assess Cx40's necessity for this process. We found that Cx40 knockdown in endothelial cells (EC) drives more aggressive sprouting angiogenesis in association with increased EC proliferation. By contrast, using electrical cell-substrate impedance sensing we observed no effect of Cx40 knockdown on EC migration. Finally, we found that Cx37 (GJA4) is reduced in Cx40-deficient EC and that targeted silencing of Cx37 alone produces a more aggressive, hypersprouting phenotype compared to control or Cx40 knockdown EC. Taken together, our data indicate that Cx40 plays multiple roles during vessel growth, including to specifically limit sprouting angiogenesis, and that this may occur, at least in part, through regulation of endothelial Cx37 levels.
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Affiliation(s)
- Edward K. Looker
- Department of Cell and Molecular Biology, School of Science and Engineering, Tulane University, New Orleans, Louisiana, USA
| | - Femke J. Aan
- Department of Biochemistry and Molecular Biology, School of Medicine, Tulane University, New Orleans, Louisiana, USA
| | - Christopher J. Hatch
- Department of Biomedical Engineering, Henry Samueli School of Engineering, University of California-Irvine, Irvine, California, USA
| | - Christopher C.W. Hughes
- Department of Biomedical Engineering, Henry Samueli School of Engineering, University of California-Irvine, Irvine, California, USA
- Department of Molecular Biology and Biochemistry, School of Biological Sciences, University of California-Irvine, Irvine, California, USA
| | - Michelle L. Matter
- Department of Biochemistry and Molecular Biology, School of Medicine, Tulane University, New Orleans, Louisiana, USA
| | - Jennifer S. Fang
- Department of Cell and Molecular Biology, School of Science and Engineering, Tulane University, New Orleans, Louisiana, USA
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3
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Kiesworo K, MacArthur MR, Kip P, Agius T, Macabrey D, Lambelet M, Hamard L, Ozaki CK, Mitchell JR, Déglise S, Mitchell SJ, Allagnat F, Longchamp A. Cystathionine-γ-lyase overexpression modulates oxidized nicotinamide adenine dinucleotide biosynthesis and enhances neovascularization. JVS Vasc Sci 2023; 4:100095. [PMID: 36852171 PMCID: PMC9958478 DOI: 10.1016/j.jvssci.2022.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 11/10/2022] [Indexed: 01/15/2023] Open
Abstract
Objective Hydrogen sulfide is a proangiogenic gas produced primarily by the transsulfuration enzyme cystathionine-γ-lyase (CGL). CGL-dependent hydrogen sulfide production is required for neovascularization in models of peripheral arterial disease. However, the benefits of increasing endogenous CGL and its mechanism of action have not yet been elucidated. Methods Male whole body CGL-overexpressing transgenic (CGLTg) mice and wild-type (WT) littermates (C57BL/6J) were subjected to the hindlimb ischemia model (age, 10-12 weeks). Functional recovery was assessed via the treadmill exercise endurance test. Leg perfusion was measured by laser Doppler imaging and vascular endothelial-cadherin immunostaining. To examine the angiogenic potential, aortic ring sprouting assay and postnatal mouse retinal vasculature development studies were performed. Finally, comparative metabolomics analysis, oxidized/reduced nicotinamide adenine dinucleotide (NAD+/NADH) analysis, and quantitative real-time polymerase chain reaction were performed on CGLWT and CGLTg gastrocnemius muscle. Results The restoration of blood flow occurred more rapidly in CGLTg mice. Compared with the CGLWT mice, the median ± standard deviation running distance and time were increased for the CGLTg mice after femoral artery ligation (159 ± 53 m vs 291 ± 74 m [P < .005] and 17 ± 4 minutes vs 27 ± 5 minutes [P < .05], respectively). Consistently, in the CGLTg ischemic gastrocnemius muscle, the capillary density was increased fourfold (0.05 ± 0.02 vs 0.20 ± 0.12; P < .005). Ex vivo, the endothelial cell (EC) sprouting length was increased in aorta isolated from CGLTg mice, especially when cultured in VEGFA (vascular endothelial growth factor A)-only media (63 ± 2 pixels vs 146 ± 52 pixels; P < .05). Metabolomics analysis demonstrated a higher level of niacinamide, a precursor of NAD+/NADH in the muscle of CGLTg mice (61.4 × 106 ± 5.9 × 106 vs 72.4 ± 7.7 × 106 area under the curve; P < .05). Similarly, the NAD+ salvage pathway gene expression was increased in CGLTg gastrocnemius muscle. Finally, CGL overexpression or supplementation with the NAD+ precursor nicotinamide mononucleotide improved EC migration in vitro (wound closure: control, 35% ± 9%; CGL, 55% ± 11%; nicotinamide mononucleotide, 42% ± 13%; P < .05). Conclusions Our results have demonstrated that CGL overexpression improves the neovascularization of skeletal muscle on hindlimb ischemia. These effects correlated with changes in the NAD pathway, which improved EC migration.
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Affiliation(s)
- Kevin Kiesworo
- Department of Vascular Surgery, Lausanne University Hospital, Lausanne, Switzerland
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | | | - Peter Kip
- Department of Surgery and Heart and Vascular Center, Brigham & Women's Hospital and Harvard Medical School, Boston, MA
| | - Thomas Agius
- Department of Vascular Surgery, Lausanne University Hospital, Lausanne, Switzerland
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | - Diane Macabrey
- Department of Vascular Surgery, Lausanne University Hospital, Lausanne, Switzerland
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | - Martine Lambelet
- Department of Vascular Surgery, Lausanne University Hospital, Lausanne, Switzerland
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | - Lauriane Hamard
- Department of Medicine, Lausanne University Hospital, Lausanne, Switzerland
| | - C.-Keith Ozaki
- Department of Surgery and Heart and Vascular Center, Brigham & Women's Hospital and Harvard Medical School, Boston, MA
| | - James R. Mitchell
- Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Sébastien Déglise
- Department of Vascular Surgery, Lausanne University Hospital, Lausanne, Switzerland
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | - Sarah J. Mitchell
- Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Florent Allagnat
- Department of Vascular Surgery, Lausanne University Hospital, Lausanne, Switzerland
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | - Alban Longchamp
- Department of Vascular Surgery, Lausanne University Hospital, Lausanne, Switzerland
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
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4
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Fang JS, Burt JM. Connexin37 Regulates Cell Cycle in the Vasculature. J Vasc Res 2022; 60:73-86. [PMID: 36067749 DOI: 10.1159/000525619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 06/08/2022] [Indexed: 11/19/2022] Open
Abstract
Control of vascular cell growth responses is critical for development and maintenance of a healthy vasculature. Connexins - the proteins comprising gap junction channels - are key regulators of cell growth in diseases such as cancer, but their involvement in controlling cell growth in the vasculature is less well appreciated. Connexin37 (Cx37) is one of four connexin isotypes expressed in the vessel wall. Its primary role in blood vessels relies on its unique ability to transduce flow-sensitive signals into changes in cell cycle status of endothelial (and perhaps, mural) cells. Here, we review available evidence for Cx37's role in the regulation of vascular growth, vessel organization, and vascular tone in healthy and diseased vasculature. We propose a novel mechanism whereby Cx37 accomplishes this with a phosphorylation-dependent transition between closed (growth-suppressive) and multiple open (growth-permissive) channel conformations that result from interactions of the C-terminus with cell-cycle regulators to limit or support cell cycle progression. Lastly, we discuss Cx37 and its downstream signaling as a novel potential target in the treatment of cardiovascular disease, and we address outstanding research questions that still challenge the development of such therapies.
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Affiliation(s)
- Jennifer S Fang
- Department of Cell and Molecular Biology, Tulane University, New Orleans, Louisiana, USA
| | - Janis M Burt
- Department of Physiology, University of Arizona, Tucson, Arizona, USA
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5
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O-GlcNAc Modification and Its Role in Diabetic Retinopathy. Metabolites 2022; 12:metabo12080725. [PMID: 36005597 PMCID: PMC9415332 DOI: 10.3390/metabo12080725] [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: 07/14/2022] [Revised: 08/01/2022] [Accepted: 08/03/2022] [Indexed: 11/17/2022] Open
Abstract
Diabetic retinopathy (DR) is a leading complication in type 1 and type 2 diabetes and has emerged as a significant health problem. Currently, there are no effective therapeutic strategies owing to its inconspicuous early lesions and complex pathological mechanisms. Therefore, the mechanism of molecular pathogenesis requires further elucidation to identify potential targets that can aid in the prevention of DR. As a type of protein translational modification, O-linked β-N-acetylglucosamine (O-GlcNAc) modification is involved in many diseases, and increasing evidence suggests that dysregulated O-GlcNAc modification is associated with DR. The present review discusses O-GlcNAc modification and its molecular mechanisms involved in DR. O-GlcNAc modification might represent a novel alternative therapeutic target for DR in the future.
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6
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Zhou Z, Chai W, Liu Y, Zhou M, Zhang X. Connexins and angiogenesis: Functional aspects, pathogenesis, and emerging therapies (Review). Int J Mol Med 2022; 50:110. [PMID: 35762312 PMCID: PMC9256078 DOI: 10.3892/ijmm.2022.5166] [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: 03/09/2022] [Accepted: 06/08/2022] [Indexed: 11/20/2022] Open
Abstract
Connexins (Cxs) play key roles in cellular communication. By facilitating metabolite exchange or interfering with distinct signaling pathways, Cxs affect cell homeostasis, proliferation, and differentiation. Variations in the activity and expression of Cxs have been linked to numerous clinical conditions including carcinomas, cardiac disorders, and wound healing. Recent discoveries on the association between Cxs and angiogenesis have sparked interest in Cx-mediated angiogenesis due to its essential functions in tissue formation, wound repair, tumor growth, and metastasis. It is now widely recognized that understanding the association between Cxs and angiogenesis may aid in the development of new targeted therapies for angiogenic diseases. The aim of the present review was to provide a comprehensive overview of Cxs and Cx-mediated angiogenesis, with a focus on therapeutic implications.
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Affiliation(s)
- Zizi Zhou
- Department of Cardio‑Thoracic Surgery, Shenzhen University General Hospital, Shenzhen, Guangdong 518055, P.R. China
| | - Wenxiang Chai
- Department of Cardio‑Thoracic Surgery, Shenzhen University General Hospital, Shenzhen, Guangdong 518055, P.R. China
| | - Yi Liu
- Department of Cardio‑Thoracic Surgery, Shenzhen University General Hospital, Shenzhen, Guangdong 518055, P.R. China
| | - Meng Zhou
- Department of Cardio‑Thoracic Surgery, Shenzhen University General Hospital, Shenzhen, Guangdong 518055, P.R. China
| | - Xiaoming Zhang
- Department of Cardio‑Thoracic Surgery, Shenzhen University General Hospital, Shenzhen, Guangdong 518055, P.R. China
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7
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Haefliger JA, Meda P, Alonso F. Endothelial Connexins in Developmental and Pathological Angiogenesis. Cold Spring Harb Perspect Med 2022; 12:a041158. [PMID: 35074793 PMCID: PMC9159259 DOI: 10.1101/cshperspect.a041158] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Connexins (Cxs) constitute a large family of transmembrane proteins that form gap junction channels, which enable the direct transfer of small signaling molecules from cell to cell. In blood vessels, Cx channels allow the endothelial cells (ECs) to respond to external and internal cues as a whole and, thus, contribute to the maintenance of vascular homeostasis. While the role of Cxs has been extensively studied in large arteries, a growing body of evidence suggests that they also play a role in the formation of microvascular networks. Since the formation of new blood vessels requires the coordinated response of ECs to external stimuli, endothelial Cxs may play an important role there. Recent studies in developmental and pathologic models reveal that EC Cxs regulate physiological and pathological angiogenesis through canonical and noncanonical functions, making these proteins potential therapeutic targets for the development of new strategies aimed at a better control of angiogenesis.
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Affiliation(s)
| | - Paolo Meda
- Department of Cell Physiology and Metabolism, University of Geneva, Medical Center, 1211 Geneva, Switzerland
| | - Florian Alonso
- Centre de Recherche Cardio-Thoracique de Bordeaux (INSERM U1045), Université de Bordeaux, 33076 Bordeaux, France
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8
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Dong Y, Alonso F, Jahjah T, Fremaux I, Grosset CF, Génot E. miR-155 regulates physiological angiogenesis but an miR-155-rich microenvironment disrupts the process by promoting unproductive endothelial sprouting. Cell Mol Life Sci 2022; 79:208. [PMID: 35347477 PMCID: PMC11072784 DOI: 10.1007/s00018-022-04231-3] [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: 12/02/2021] [Revised: 03/03/2022] [Accepted: 03/07/2022] [Indexed: 11/30/2022]
Abstract
Angiogenesis involves cell specification orchestrated by regulatory interactions between the vascular endothelial growth factor and Notch signaling pathways. However, the role of microRNAs in these regulations remains poorly explored. Here we show that a controlled level of miR-155 is essential for proper angiogenesis. In the mouse retina angiogenesis model, antimiR-155 altered neovascularization. In vitro assays established that endogenous miR-155 is involved in podosome formation, activation of the proteolytic machinery and cell migration but not in morphogenesis. The role of miR-155 was explored using miR-155 mimics. In vivo, exposing the developing vasculature to miR-155 promoted hypersprouting, thus phenocopying defects associated with Notch deficiency. Mechanistically, miR-155 overexpression weakened Notch signaling by reducing Smad1/5 expression, leading to the formation of tip cell-like cells which did not reach full invasive capacity and became unable to undergo morphogenesis. These results identify miR-155 as a novel regulator of physiological angiogenesis and as a novel actor of pathological angiogenesis.
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Affiliation(s)
- Yuechao Dong
- Univ. Bordeaux, INSERM, Centre de Recherche cardio-thoracique de Bordeaux, U1045, 33000, Bordeaux, France
| | - Florian Alonso
- Univ. Bordeaux, INSERM, Centre de Recherche cardio-thoracique de Bordeaux, U1045, 33000, Bordeaux, France
| | - Tiya Jahjah
- Univ. Bordeaux, INSERM, Centre de Recherche cardio-thoracique de Bordeaux, U1045, 33000, Bordeaux, France
| | - Isabelle Fremaux
- Univ. Bordeaux, INSERM, Centre de Recherche cardio-thoracique de Bordeaux, U1045, 33000, Bordeaux, France
| | - Christophe F Grosset
- Univ. of Bordeaux, INSERM, Biotherapy of Genetic Diseases, Inflammatory Disorders and Cancer, U1035, 33000, Bordeaux, France
| | - Elisabeth Génot
- Univ. Bordeaux, INSERM, Centre de Recherche cardio-thoracique de Bordeaux, U1045, 33000, Bordeaux, France.
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9
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Sathiyanadan K, Alonso F, Domingos-Pereira S, Santoro T, Hamard L, Cesson V, Meda P, Nardelli-Haefliger D, Haefliger JA. Targeting Endothelial Connexin37 Reduces Angiogenesis and Decreases Tumor Growth. Int J Mol Sci 2022; 23:2930. [PMID: 35328350 PMCID: PMC8948817 DOI: 10.3390/ijms23062930] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 02/28/2022] [Accepted: 03/03/2022] [Indexed: 12/13/2022] Open
Abstract
Connexin37 (Cx37) and Cx40 form intercellular channels between endothelial cells (EC), which contribute to the regulation of the functions of vessels. We previously documented the participation of both Cx in developmental angiogenesis and have further shown that loss of Cx40 decreases the growth of different tumors. Here, we report that loss of Cx37 reduces (1) the in vitro proliferation of primary human EC; (2) the vascularization of subcutaneously implanted matrigel plugs in Cx37-/- mice or in WT using matrigel plugs supplemented with a peptide targeting Cx37 channels; (3) tumor angiogenesis; and (4) the growth of TC-1 and B16 tumors, resulting in a longer mice survival. We further document that Cx37 and Cx40 function in a collaborative manner to promote tumor growth, inasmuch as the injection of a peptide targeting Cx40 into Cx37-/- mice decreased the growth of TC-1 tumors to a larger extent than after loss of Cx37. This loss did not alter vessel perfusion, mural cells coverage and tumor hypoxia compared to tumors grown in WT mice. The data show that Cx37 is relevant for the control of EC proliferation and growth in different tumor models, suggesting that it may be a target, alone or in combination with Cx40, in the development of anti-tumoral treatments.
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Affiliation(s)
- Karthik Sathiyanadan
- Department of Urology, Lausanne University Hospital, 1011 Lausanne, Switzerland; (K.S.); (S.D.-P.); (V.C.); (D.N.-H.)
| | - Florian Alonso
- Laboratory for the Bioengineering of Tissues (BioTis-INSERM U1026), Université de Bordeaux, 33607 Bordeaux, France;
| | - Sonia Domingos-Pereira
- Department of Urology, Lausanne University Hospital, 1011 Lausanne, Switzerland; (K.S.); (S.D.-P.); (V.C.); (D.N.-H.)
| | - Tania Santoro
- Department of Medicine, Lausanne University Hospital, 1011 Lausanne, Switzerland; (T.S.); (L.H.)
| | - Lauriane Hamard
- Department of Medicine, Lausanne University Hospital, 1011 Lausanne, Switzerland; (T.S.); (L.H.)
| | - Valérie Cesson
- Department of Urology, Lausanne University Hospital, 1011 Lausanne, Switzerland; (K.S.); (S.D.-P.); (V.C.); (D.N.-H.)
| | - Paolo Meda
- Department of Cell Physiology and Metabolism, Medical Center, University of Geneva, 1206 Geneva, Switzerland;
| | - Denise Nardelli-Haefliger
- Department of Urology, Lausanne University Hospital, 1011 Lausanne, Switzerland; (K.S.); (S.D.-P.); (V.C.); (D.N.-H.)
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10
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Raftrey B, Williams I, Rios Coronado PE, Fan X, Chang AH, Zhao M, Roth R, Trimm E, Racelis R, D’Amato G, Phansalkar R, Nguyen A, Chai T, Gonzalez KM, Zhang Y, Ang LT, Loh K, Bernstein D, Red-Horse K. Dach1 Extends Artery Networks and Protects Against Cardiac Injury. Circ Res 2021; 129:702-716. [PMID: 34383559 PMCID: PMC8448957 DOI: 10.1161/circresaha.120.318271] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 08/11/2021] [Indexed: 11/16/2022]
Abstract
[Figure: see text].
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Affiliation(s)
| | - Ian Williams
- Biology, Stanford University, Stanford, CA, 94305
| | | | - Xiaochen Fan
- Biology, Stanford University, Stanford, CA, 94305
| | - Andrew H. Chang
- Biology, Stanford University, Stanford, CA, 94305
- Developmental Biology, Stanford University School of Medicine, Stanford, CA, 94305
| | - Mingming Zhao
- Division of Pediatric Cardiology, Department of Pediatrics, Stanford University School of Medicine, Stanford, CA, 94305
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Robert Roth
- Biology, Stanford University, Stanford, CA, 94305
| | - Emily Trimm
- Biology, Stanford University, Stanford, CA, 94305
| | | | | | - Ragini Phansalkar
- Biology, Stanford University, Stanford, CA, 94305
- Genetics, Stanford University School of Medicine, Stanford, CA, 94305
| | - Alana Nguyen
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Timothy Chai
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Karen M. Gonzalez
- Biology, Stanford University, Stanford, CA, 94305
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Yue Zhang
- Biology, Stanford University, Stanford, CA, 94305
| | - Lay Teng Ang
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Kyle Loh
- Developmental Biology, Stanford University School of Medicine, Stanford, CA, 94305
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Daniel Bernstein
- Division of Pediatric Cardiology, Department of Pediatrics, Stanford University School of Medicine, Stanford, CA, 94305
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Kristy Red-Horse
- Biology, Stanford University, Stanford, CA, 94305
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
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11
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Koepple C, Zhou Z, Huber L, Schulte M, Schmidt K, Gloe T, Kneser U, Schmidt VJ, de Wit C. Expression of Connexin43 Stimulates Endothelial Angiogenesis Independently of Gap Junctional Communication In Vitro. Int J Mol Sci 2021; 22:ijms22147400. [PMID: 34299018 PMCID: PMC8306600 DOI: 10.3390/ijms22147400] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/02/2021] [Accepted: 07/07/2021] [Indexed: 12/14/2022] Open
Abstract
Connexins (Cx) form gap junctions (GJ) and allow for intercellular communication. However, these proteins also modulate gene expression, growth, and cell migration. The downregulation of Cx43 impairs endothelial cell migration and angiogenetic potential. Conversely, endothelial Cx43 expression is upregulated in an in vivo angiogenesis model relying on hemodynamic forces. We studied the effects of Cx43 expression on tube formation and proliferation in HUVECs and examined its dependency on GJ communication. Expectedly, intercellular communication assessed by dye transfer was linked to Cx43 expression levels in HUVECs and was sensitive to a GJ blockade by the Cx43 mimetic peptide Gap27. The proliferation of HUVECs was not affected by Cx43 overexpression using Cx43 cDNA transfection, siRNA-mediated knockdown of Cx43, or the inhibition of GJ compared to the controls (transfection of an empty vector, scrambled siRNA, and the solvent). In contrast, endothelial tube and sprout formation in HUVECs was minimized after Cx43 knockdown and significantly enhanced after Cx43 overexpression. This was not affected by a GJ blockade (Gap27). We conclude that Cx43 expression positively modulates the angiogenic potential of endothelial cells independent of GJ communication. Since proliferation remained unaffected, we suggest that Cx43 protein may modulate endothelial cell migration, thereby supporting angiogenesis. The modulation of Cx43 expression may represent an exploitable principle for angiogenesis induction in clinical therapy.
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Affiliation(s)
- Christoph Koepple
- Department for Hand Surgery, Plastic Surgery and Reconstructive Surgery, BG Trauma Center Ludwigshafen, Heidelberg University, 67071 Ludwigshafen, Germany; (Z.Z.); (L.H.); (M.S.); (U.K.)
- Correspondence: (C.K.); (V.J.S.); (C.d.W.)
| | - Zizi Zhou
- Department for Hand Surgery, Plastic Surgery and Reconstructive Surgery, BG Trauma Center Ludwigshafen, Heidelberg University, 67071 Ludwigshafen, Germany; (Z.Z.); (L.H.); (M.S.); (U.K.)
| | - Lena Huber
- Department for Hand Surgery, Plastic Surgery and Reconstructive Surgery, BG Trauma Center Ludwigshafen, Heidelberg University, 67071 Ludwigshafen, Germany; (Z.Z.); (L.H.); (M.S.); (U.K.)
| | - Matthias Schulte
- Department for Hand Surgery, Plastic Surgery and Reconstructive Surgery, BG Trauma Center Ludwigshafen, Heidelberg University, 67071 Ludwigshafen, Germany; (Z.Z.); (L.H.); (M.S.); (U.K.)
| | - Kjestine Schmidt
- Institut für Physiologie, Universität zu Lübeck, 23562 Lübeck, Germany;
- Deutsches Zentrum für Herz-Kreislauf-Forschung (DZHK) e.V. (German Center for Cardiovascular Research), 23562 Lübeck, Germany
| | - Torsten Gloe
- Physiology, Institute of Theoretical Medicine, Universität Augsburg, 86159 Augsburg, Germany;
| | - Ulrich Kneser
- Department for Hand Surgery, Plastic Surgery and Reconstructive Surgery, BG Trauma Center Ludwigshafen, Heidelberg University, 67071 Ludwigshafen, Germany; (Z.Z.); (L.H.); (M.S.); (U.K.)
| | - Volker Jürgen Schmidt
- Department for Plastic Surgery and Breast Surgery, Zealand University Hospital (SUH) Roskilde, Copenhagen University, 4000 Roskilde, Denmark
- Correspondence: (C.K.); (V.J.S.); (C.d.W.)
| | - Cor de Wit
- Institut für Physiologie, Universität zu Lübeck, 23562 Lübeck, Germany;
- Deutsches Zentrum für Herz-Kreislauf-Forschung (DZHK) e.V. (German Center for Cardiovascular Research), 23562 Lübeck, Germany
- Correspondence: (C.K.); (V.J.S.); (C.d.W.)
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Iturriaga-Goyon E, Buentello-Volante B, Magaña-Guerrero FS, Garfias Y. Future Perspectives of Therapeutic, Diagnostic and Prognostic Aptamers in Eye Pathological Angiogenesis. Cells 2021; 10:cells10061455. [PMID: 34200613 PMCID: PMC8227682 DOI: 10.3390/cells10061455] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/04/2021] [Accepted: 06/05/2021] [Indexed: 12/23/2022] Open
Abstract
Aptamers are single-stranded DNA or RNA oligonucleotides that are currently used in clinical trials due to their selectivity and specificity to bind small molecules such as proteins, peptides, viral particles, vitamins, metal ions and even whole cells. Aptamers are highly specific to their targets, they are smaller than antibodies and fragment antibodies, they can be easily conjugated to multiple surfaces and ions and controllable post-production modifications can be performed. Aptamers have been therapeutically used for age-related macular degeneration, cancer, thrombosis and inflammatory diseases. The aim of this review is to highlight the therapeutic, diagnostic and prognostic possibilities associated with aptamers, focusing on eye pathological angiogenesis.
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Affiliation(s)
- Emilio Iturriaga-Goyon
- MD/PhD (PECEM) Program, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico;
- Cell and Tissue Biology, Research Unit, Institute of Ophthalmology, Conde de Valenciana, Chimalpopoca 14, Mexico City 06800, Mexico; (B.B.-V.); (F.S.M.-G.)
- Department of Biochemistry, Facultad de Medicina, Universidad Nacional Autónoma de México, Av. Universidad 3000, Mexico City 04510, Mexico
| | - Beatriz Buentello-Volante
- Cell and Tissue Biology, Research Unit, Institute of Ophthalmology, Conde de Valenciana, Chimalpopoca 14, Mexico City 06800, Mexico; (B.B.-V.); (F.S.M.-G.)
| | - Fátima Sofía Magaña-Guerrero
- Cell and Tissue Biology, Research Unit, Institute of Ophthalmology, Conde de Valenciana, Chimalpopoca 14, Mexico City 06800, Mexico; (B.B.-V.); (F.S.M.-G.)
| | - Yonathan Garfias
- Cell and Tissue Biology, Research Unit, Institute of Ophthalmology, Conde de Valenciana, Chimalpopoca 14, Mexico City 06800, Mexico; (B.B.-V.); (F.S.M.-G.)
- Department of Biochemistry, Facultad de Medicina, Universidad Nacional Autónoma de México, Av. Universidad 3000, Mexico City 04510, Mexico
- Correspondence:
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13
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González-Casanova J, Schmachtenberg O, Martínez AD, Sanchez HA, Harcha PA, Rojas-Gomez D. An Update on Connexin Gap Junction and Hemichannels in Diabetic Retinopathy. Int J Mol Sci 2021; 22:ijms22063194. [PMID: 33801118 PMCID: PMC8004116 DOI: 10.3390/ijms22063194] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 03/06/2021] [Accepted: 03/10/2021] [Indexed: 01/10/2023] Open
Abstract
Diabetic retinopathy (DR) is one of the main causes of vision loss in the working age population. It is characterized by a progressive deterioration of the retinal microvasculature, caused by long-term metabolic alterations inherent to diabetes, leading to a progressive loss of retinal integrity and function. The mammalian retina presents an orderly layered structure that executes initial but complex visual processing and analysis. Gap junction channels (GJC) forming electrical synapses are present in each retinal layer and contribute to the communication between different cell types. In addition, connexin hemichannels (HCs) have emerged as relevant players that influence diverse physiological and pathological processes in the retina. This article highlights the impact of diabetic conditions on GJC and HCs physiology and their involvement in DR pathogenesis. Microvascular damage and concomitant loss of endothelial cells and pericytes are related to alterations in gap junction intercellular communication (GJIC) and decreased connexin 43 (Cx43) expression. On the other hand, it has been shown that the expression and activity of HCs are upregulated in DR, becoming a key element in the establishment of proinflammatory conditions that emerge during hyperglycemia. Hence, novel connexin HCs blockers or drugs to enhance GJIC are promising tools for the development of pharmacological interventions for diabetic retinopathy, and initial in vitro and in vivo studies have shown favorable results in this regard.
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Affiliation(s)
- Jorge González-Casanova
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago 8910060, Chile;
| | - Oliver Schmachtenberg
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Biología, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360102, Chile;
| | - Agustín D. Martínez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360102, Chile; (A.D.M.); (H.A.S.); (P.A.H.)
| | - Helmuth A. Sanchez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360102, Chile; (A.D.M.); (H.A.S.); (P.A.H.)
| | - Paloma A. Harcha
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360102, Chile; (A.D.M.); (H.A.S.); (P.A.H.)
| | - Diana Rojas-Gomez
- Escuela de Nutrición y Dietética, Facultad de Medicina, Universidad Andres Bello, Santiago 8370146, Chile
- Correspondence: ; Tel.: +56-2-26618559
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Abstract
Of the 21 members of the connexin family, 4 (Cx37, Cx40, Cx43, and Cx45) are expressed in the endothelium and/or smooth muscle of intact blood vessels to a variable and dynamically regulated degree. Full-length connexins oligomerize and form channel structures connecting the cytosol of adjacent cells (gap junctions) or the cytosol with the extracellular space (hemichannels). The different connexins vary mainly with regard to length and sequence of their cytosolic COOH-terminal tails. These COOH-terminal parts, which in the case of Cx43 are also translated as independent short isoforms, are involved in various cellular signaling cascades and regulate cell functions. This review focuses on channel-dependent and -independent effects of connexins in vascular cells. Channels play an essential role in coordinating and synchronizing endothelial and smooth muscle activity and in their interplay, in the control of vasomotor actions of blood vessels including endothelial cell reactivity to agonist stimulation, nitric oxide-dependent dilation, and endothelial-derived hyperpolarizing factor-type responses. Further channel-dependent and -independent roles of connexins in blood vessel function range from basic processes of vascular remodeling and angiogenesis to vascular permeability and interactions with leukocytes with the vessel wall. Together, these connexin functions constitute an often underestimated basis for the enormous plasticity of vascular morphology and function enabling the required dynamic adaptation of the vascular system to varying tissue demands.
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Affiliation(s)
- Ulrich Pohl
- Walter-Brendel-Centre of Experimental Medicine, University Hospital, LMU Munich, Planegg-Martinsried, Germany; Biomedical Centre, Cardiovascular Physiology, LMU Munich, Planegg-Martinsried, Germany; German Centre for Cardiovascular Research, Partner Site Munich Heart Alliance, Munich, Germany; and Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
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15
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Caufriez A, Böck D, Martin C, Ballet S, Vinken M. Peptide-based targeting of connexins and pannexins for therapeutic purposes. Expert Opin Drug Discov 2020; 15:1213-1222. [PMID: 32539572 DOI: 10.1080/17460441.2020.1773787] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
INTRODUCTION Connexin and pannexin (hemi)channels play an important role in paracrine and autocrine signaling pathways. The opening of these cellular pores is linked to a wide range of diseases. Therefore, pharmacological closing of connexin and pannexin (hemi)channels seems a promising therapeutic strategy. However, the currently available inhibitors cope with recurring problems concerning selectivity, specificity, stability and/or solubility. AREAS COVERED A number of peptides that mimic specific regions in the native sequence of connexins and pannexins have the potential to overcome some of these hurdles. In this paper, an overview is provided on these peptide-based inhibitors of connexin and pannexin (hemi)channels for therapeutic purposes. The authors also provide the reader with their expert perspectives on the future of these peptide-based inhibitors. EXPERT OPINION Peptide mimetics can become valuable tools in the treatment of connexin-related and pannexin-related diseases. This can be made possible provided that available peptides are optimized, and new peptide mimetics are designed based on knowledge of the mechanisms underlying the gating control of connexin and pannexin (hemi)channels.
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Affiliation(s)
- Anne Caufriez
- Department of in Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel , 1090, Brussels, Belgium
| | - Denise Böck
- Department of in Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel , 1090, Brussels, Belgium
| | - Charlotte Martin
- Department of Organic Chemistry, Vrije Universiteit Brussel , 1050, Brussels, Belgium
| | - Steven Ballet
- Department of Organic Chemistry, Vrije Universiteit Brussel , 1050, Brussels, Belgium
| | - Mathieu Vinken
- Department of in Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel , 1090, Brussels, Belgium
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16
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Hamard L, Santoro T, Allagnat F, Meda P, Nardelli-Haefliger D, Alonso F, Haefliger JA. Targeting connexin37 alters angiogenesis and arteriovenous differentiation in the developing mouse retina. FASEB J 2020; 34:8234-8249. [PMID: 32323401 DOI: 10.1096/fj.202000257r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 03/20/2020] [Accepted: 04/06/2020] [Indexed: 11/11/2022]
Abstract
Connexin37 (Cx37) forms intercellular channels between endothelial cells (EC), and contributes to coordinate the motor tone of vessels. We investigated the contribution of this protein during physiological angiogenesis. We show that, compared to WT littermates, mice lacking Cx37 (Cx37-/- ) featured (i) a decreased extension of the superficial vascular plexus during the first 4 days after birth; (ii) an increased vascular density at the angiogenic front at P6, due to an increase in the proliferative rate of EC and in the sprouting of the venous compartment, as well as to a somewhat displaced position of tip cells; (iii) a decreased coverage of newly formed arteries and veins by mural cells; (iv) altered ERK-dependent endothelial cells proliferation through the EphB4 signaling pathway, which is involved in the specification of veins and arteries. In vitro studies documented that, in the absence of Cx37, human venous EC (HUVEC) released less platelet-derived growth factor (PDGF) and more Angiopoietin-2, two molecules involved in the recruitment of mural cells. Treatment of mice with DAPT, an inhibitor of the Notch pathway, decreased the expression of Cx37, and partially mimicked in WT retinas, the alterations observed in Cx37-/- mice. Thus, Cx37 contributes to (i) the early angiogenesis of retina, by interacting with the Notch pathway; (ii) the growth and maturation of neo-vessels, by modulating tip, stalk, and mural cells; (iii) the regulation of arteriovenous specification, thus, representing a novel target for treatments of retina diseases.
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Affiliation(s)
- Lauriane Hamard
- Department of Medicine, Lausanne University Hospital, Lausanne, Switzerland
| | - Tania Santoro
- Department of Medicine, Lausanne University Hospital, Lausanne, Switzerland
| | - Florent Allagnat
- Department of Medicine, Lausanne University Hospital, Lausanne, Switzerland
| | - Paolo Meda
- Department of Cell Physiology and Metabolism, Medical Center, University of Geneva, Geneva, Switzerland
| | | | - Florian Alonso
- Centre de Recherche Cardio-Thoracique de Bordeaux (INSERM U1045), Université de Bordeaux, Bordeaux, France
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17
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Hautefort A, Pfenniger A, Kwak BR. Endothelial connexins in vascular function. VASCULAR BIOLOGY 2019; 1:H117-H124. [PMID: 32923963 PMCID: PMC7439941 DOI: 10.1530/vb-19-0015] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 11/07/2019] [Indexed: 12/22/2022]
Abstract
Gap junctions are essential for intercellular crosstalk in blood and lymphatic vasculature. These clusters of intercellular channels ensure direct communication among endothelial cells and between endothelial and smooth muscle cells, and the synchronization of their behavior along the vascular tree. Gap junction channels are formed by connexins; six connexins form a connexon or hemichannel and the docking of two connexons result in a full gap junction channel allowing for the exchange of ions and small metabolites between neighboring cells. Recent evidence indicates that the intracellular domains of connexins may also function as an interaction platform (interactome) for other proteins, thereby regulating their function. Interestingly, fragments of Cx proteins generated by alternative internal translation were recently described, although their functions in the vascular wall remain to be uncovered. Variations in connexin expression are observed along different types of blood and lymphatic vessels; the most commonly found endothelial connexins are Cx37, Cx40, Cx43 and Cx47. Physiological studies on connexin-knockout mice demonstrated the essential roles of these channel-forming proteins in the coordination of vasomotor activity, endothelial permeability and inflammation, angiogenesis and in the maintenance of fluid balance in the body.
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Affiliation(s)
- Aurélie Hautefort
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
| | - Anna Pfenniger
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland.,Department of Medical Specializations - Cardiology, University of Geneva, Geneva, Switzerland
| | - Brenda R Kwak
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland.,Department of Medical Specializations - Cardiology, University of Geneva, Geneva, Switzerland
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18
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Ivanova E, Kovacs-Oller T, Sagdullaev BT. Domain-specific distribution of gap junctions defines cellular coupling to establish a vascular relay in the retina. J Comp Neurol 2019; 527:2675-2693. [PMID: 30950036 PMCID: PMC6721971 DOI: 10.1002/cne.24699] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/02/2019] [Accepted: 04/02/2019] [Indexed: 12/22/2022]
Abstract
In the retina, diverse functions of neuronal gap junctions (GJs) have been established. However, the distribution and function of vascular GJs are less clear. Here in the mouse retina whole mounts, we combined structural immunohistochemical analysis and a functional assessment of cellular coupling with a GJ-permeable tracer Neurobiotin to determine distribution patterns of three major vascular connexins. We found that Cx43 was expressed in punctate fashion on astroglia, surrounding all types of blood vessels and in continuous string-like structures along endothelial cell contacts in specialized regions of the vascular tree. Specifically, these Cx43-positive strings originated at the finest capillaries and extended toward the feeding artery. As this structural arrangement promoted strong and exclusive coupling of pericytes and endothelial cells along the corresponding branch, we termed this region a "vascular relay." Cx40 expression was found predominantly along the endothelial cell contacts of the primary arteries and did not overlap with Cx43-positive strings. At their occupied territories, Cx43 and Cx40 clustered with tight junctions and, to a lesser extent, with adhesion contacts, both key elements of the blood-retina barrier. Finally, Cx37 puncta were associated with the entire surface of both mural and endothelial cells across all regions of the vascular tree. This combinatorial analysis of vascular connexins and identification of the vascular relay region will serve as a structural foundation for future studies of neurovascular signaling in health and disease.
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Affiliation(s)
- Elena Ivanova
- Burke Neurological Institute, Department of Ophthalmology, Weill Cornell Medicine, White Plains, New York
| | - Tamas Kovacs-Oller
- Burke Neurological Institute, Department of Ophthalmology, Weill Cornell Medicine, White Plains, New York
| | - Botir T Sagdullaev
- Burke Neurological Institute, Department of Ophthalmology, Weill Cornell Medicine, White Plains, New York
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19
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Lu HS, Schmidt AM, Hegele RA, Mackman N, Rader DJ, Weber C, Daugherty A. Reporting Sex and Sex Differences in Preclinical Studies. Arterioscler Thromb Vasc Biol 2019; 38:e171-e184. [PMID: 30354222 DOI: 10.1161/atvbaha.118.311717] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Hong S Lu
- From the Department of Physiology, Saha Cardiovascular Research Center, University of Kentucky, Lexington (H.S.L., A.D.)
| | - Ann Marie Schmidt
- Diabetes Research Program, Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, New York University Langone Medical Center, New York, NY (A.M.S.)
| | - Robert A Hegele
- Department of Medicine and Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada (R.A.H.)
| | - Nigel Mackman
- Department of Medicine, University of North Carolina at Chapel Hill (N.M.)
| | - Daniel J Rader
- Department of Medicine (D.J.R.), Perelman School of Medicine, University of Pennsylvania, Philadelphia.,Department of Genetics (D.J.R.), Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Christian Weber
- Department of Medicine, Institute for Cardiovascular Prevention, Ludwig-Maximilians-Universität, Munich, Germany (C.W.).,German Centre for Cardiovascular Research, Partner Site Munich Heart Alliance, Munich, Germany (C.W.)
| | - Alan Daugherty
- From the Department of Physiology, Saha Cardiovascular Research Center, University of Kentucky, Lexington (H.S.L., A.D.)
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20
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Abstract
The systemic circulation depends upon a highly organized, hierarchal blood vascular network that requires the successful specification of arterial and venous endothelial cells during development. This process is driven by a cascade of signaling events (including Hedgehog, vascular endothelial growth factor (VEGF), Notch, connexin (Cx), transforming growth factor-beta (TGF- β), and COUP transcription factor 2 (COUP-TFII)) to influence endothelial cell cycle status and expression of arterial or venous genes and is further regulated by hemodynamic flow. Failure of endothelial cells to properly undergo arteriovenous specification may contribute to vascular malformation and dysfunction, such as in hereditary hemorrhagic telangiectasia (HHT) and capillary malformation-arteriovenous malformation (CM-AVM) where abnormal vessel structures, such as large shunts lacking clear arteriovenous identity and function, form and compromise peripheral blood flow. This review provides an overview of recent findings in the field of arteriovenous specification and highlights key regulators of this process.
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Affiliation(s)
- Jennifer Fang
- Department of Molecular Biology and Biochemistry, School of Biological Sciences, University of California, Irvine, Irvine, CA, 92697, USA
| | - Karen Hirschi
- 2Departments of Medicine, Genetics, and Biomedical Engineering, Yale Cardiovascular Research Center, Yale Stem Cell Center, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06520, USA
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21
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Aasen T, Leithe E, Graham SV, Kameritsch P, Mayán MD, Mesnil M, Pogoda K, Tabernero A. Connexins in cancer: bridging the gap to the clinic. Oncogene 2019; 38:4429-4451. [PMID: 30814684 PMCID: PMC6555763 DOI: 10.1038/s41388-019-0741-6] [Citation(s) in RCA: 139] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 01/26/2019] [Accepted: 01/26/2019] [Indexed: 02/08/2023]
Abstract
Gap junctions comprise arrays of intercellular channels formed by connexin proteins and provide for the direct communication between adjacent cells. This type of intercellular communication permits the coordination of cellular activities and plays key roles in the control of cell growth and differentiation and in the maintenance of tissue homoeostasis. After more than 50 years, deciphering the links among connexins, gap junctions and cancer, researchers are now beginning to translate this knowledge to the clinic. The emergence of new strategies for connexin targeting, combined with an improved understanding of the molecular bases underlying the dysregulation of connexins during cancer development, offers novel opportunities for clinical applications. However, different connexin isoforms have diverse channel-dependent and -independent functions that are tissue and stage specific. This can elicit both pro- and anti-tumorigenic effects that engender significant challenges in the path towards personalised medicine. Here, we review the current understanding of the role of connexins and gap junctions in cancer, with particular focus on the recent progress made in determining their prognostic and therapeutic potential.
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Affiliation(s)
- Trond Aasen
- Translational Molecular Pathology, Vall d'Hebron Institute of Research (VHIR), Autonomous University of Barcelona, CIBERONC, Barcelona, Spain.
| | - Edward Leithe
- Department of Molecular Oncology, Institute for Cancer Research, Oslo University Hospital and K.G. Jebsen Colorectal Cancer Research Centre, Oslo University Hospital, Oslo, Norway
| | - Sheila V Graham
- MRC-University of Glasgow Centre for Virus Research, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Petra Kameritsch
- Walter Brendel Centre of Experimental Medicine, Ludwig-Maximilians-Universität München and Munich University Hospital, München, Germany
| | - María D Mayán
- CellCOM Research Group, Instituto de Investigación Biomédica de A Coruña (INIBIC), Servizo Galego de Saúde (SERGAS), University of A Coruña, A Coruña, Spain
| | - Marc Mesnil
- STIM Laboratory, Faculté des Sciences Fondamentales et Appliquées, Université de Poitiers, Poitiers, France
| | - Kristin Pogoda
- Walter Brendel Centre of Experimental Medicine, Ludwig-Maximilians-Universität München and Munich University Hospital, München, Germany
| | - Arantxa Tabernero
- Departamento de Bioquímica y Biología Molecular, Instituto de Neurociencias de Castilla y León (INCYL), Universidad de Salamanca, Salamanca, Spain.
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22
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Le Gal L, Pellegrin M, Santoro T, Mazzolai L, Kurtz A, Meda P, Wagner C, Haefliger J. Connexin37-Dependent Mechanisms Selectively Contribute to Modulate Angiotensin II -Mediated Hypertension. J Am Heart Assoc 2019; 8:e010823. [PMID: 30943815 PMCID: PMC6507190 DOI: 10.1161/jaha.118.010823] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 01/30/2019] [Indexed: 12/23/2022]
Abstract
Background Gap junction channels made of Connexin37 (Cx37) are expressed by aortic endothelial and smooth muscle cells of hypertensive mice, as well as by the renin-secreting cells of kidneys. Methods and Results To decipher whether Cx37 has any role in hypertension, angiotensin II (Ang II ) was infused in normotensive wild-type and Cx37-deficient mice (Cx37-/-). After 2 to 4 weeks, the resulting increase in blood pressure was lower in Cx37-/- than in wild-type mice, suggesting an alteration in the Ang II response. To investigate this possibility, mice were submitted to a 2-kidney, 1-clip procedure, a renin-dependent model of hypertension. Two weeks after this clipping, Cx37-/- mice were less hypertensive than wild-type mice and, 2 weeks later, their blood pressure had returned to control values, in spite of abnormally high plasma renin levels. In contrast, Cx37-/- and wild-type mice that received N-nitro-l-arginine-methyl-ester, a renin-independent model of hypertension, featured a similar and sustained increase in blood pressure. The data indicate that loss of Cx37 selectively altered the Ang II -dependent pathways. Consistent with this conclusion, aortas of Cx37-/- mice featured an increased basal expression of the Ang II type 2 receptors ( AT 2R), and increased transcripts levels of downstream signaling proteins, such as Cnksr1 and Ptpn6 ( SHP -1). Accordingly, the response of Cx37-/- mice aortas to an ex vivo Ang II exposure was altered, since phosphorylation levels of several proteins of the Ang II pathway ( MLC 2, ERK , and AKT ) remained unchanged. Conclusions These findings provide evidence that Cx37 selectively influences Ang II signaling, mostly via a modulation of the expression of the Ang II type 2 receptor.
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Affiliation(s)
- Loïc Le Gal
- Department of MedicineUniversity of LausanneSwitzerland
| | - Maxime Pellegrin
- Division of AngiologyHeart and Vessel DepartmentCentre Hospitalier Universitaire VaudoisUniversity of LausanneSwitzerland
| | - Tania Santoro
- Department of MedicineUniversity of LausanneSwitzerland
| | - Lucia Mazzolai
- Division of AngiologyHeart and Vessel DepartmentCentre Hospitalier Universitaire VaudoisUniversity of LausanneSwitzerland
| | - Armin Kurtz
- Department of PhysiologyUniversity of RegensburgGermany
| | - Paolo Meda
- Department of Cell Physiology and MetabolismSchool of MedicineCMUUniversity of GenevaSwitzerland
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23
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Meyer JH, Larsen PP, Strack C, Harmening WM, Krohne TU, Holz FG, Schmitz-Valckenberg S. Optical coherence tomography angiography (OCT-A) in an animal model of laser-induced choroidal neovascularization. Exp Eye Res 2019; 184:162-171. [PMID: 31002822 DOI: 10.1016/j.exer.2019.04.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 03/18/2019] [Accepted: 04/04/2019] [Indexed: 12/17/2022]
Abstract
Aim of the study was to compare optical coherence tomography angiography (OCT-A) and conventional fluorescein angiography (FA) for quantitative analysis of the retinal and choroidal vasculature in the animal model of laser-induced choroidal neovascularization (CNV). Therefore, Dark Agouti rats underwent argon laser photocoagulation to induce CNV at D0. In vivo imaging using combined confocal scanner laser ophthalmoscopy (cSLO)-based FA and OCT-A (Heidelberg Engineering GmbH, Heidelberg, Germany) was performed before and immediately after laser treatment as well as at day 2, 7, 14 and 21. OCT-A en-face images were compared to cSLO images obtained by conventional FA topographic uptake recorded using a series of different pre-defined focus settings. For a quantitative comparison of CNV imaging by OCT-A and FA, CNV area, vessel density, number of vessel junctions, total vessel length and number of vessel end points were analyzed. Subsequent ex vivo analyses of the CNV included immunofluorescence staining of vessels in retinal and RPE/choroidal/scleral flatmount preparations. We found, that OCT-A allowed for high-resolution non-invasive imaging of the superficial, intermediate and deep retinal capillary plexus as well as the choroidal blood vessels in rats. Compared with OCT-A, visualization of CNV progression by invasive FA was less accurate, in particular the deep vascular plexus was visualized in more detail by OCT-A. The area of neovascularization was mainly detected in the deep retinal vascular plexus, outer nuclear layer (ONL), ellipsoid zone (EZ) and the choroid. Within the laser lesions, signs of CNV formation occurred at day 7 with progression in size and number of small vessels until day 21. Due to leakage and staining effects, CNV areas appeared significantly larger in FA compared to OCT-A images (p ≤ 0.0001 for all tested layers). Vessel density, number of vessel junctions, total vessel length and number of vessel end points were significantly higher in intermediate vascular plexus (IVP) and deep vascular plexus (DVP) in OCT-A compared to FA images. Overall, CNV area in flatmounts was similar to OCT-A results and much smaller compared to the area of dye leakage by FA. This study demonstrates that in vivo OCT-A imaging in small animals is feasible and allows for precise analysis of the formation of new blood vessel formation in the animal model of laser-induced CNV. Given its superior axial resolution, sensitivity and non-invasiveness compared to conventional FA imaging, OCT-A opens the door for a more detailed evaluation of CNV development in such a model and, thus, enables the analysis of the response to novel therapeutic interventions in longitudinal in vivo studies.
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Affiliation(s)
- Johanna H Meyer
- Department of Ophthalmology, University of Bonn, Bonn, Germany.
| | - Petra P Larsen
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Claudine Strack
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | | | - Tim U Krohne
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Frank G Holz
- Department of Ophthalmology, University of Bonn, Bonn, Germany
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The Functional Implications of Endothelial Gap Junctions and Cellular Mechanics in Vascular Angiogenesis. Cancers (Basel) 2019; 11:cancers11020237. [PMID: 30781714 PMCID: PMC6406946 DOI: 10.3390/cancers11020237] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2018] [Revised: 02/08/2019] [Accepted: 02/13/2019] [Indexed: 12/27/2022] Open
Abstract
Angiogenesis—the sprouting and growth of new blood vessels from the existing vasculature—is an important contributor to tumor development, since it facilitates the supply of oxygen and nutrients to cancer cells. Endothelial cells are critically affected during the angiogenic process as their proliferation, motility, and morphology are modulated by pro-angiogenic and environmental factors associated with tumor tissues and cancer cells. Recent in vivo and in vitro studies have revealed that the gap junctions of endothelial cells also participate in the promotion of angiogenesis. Pro-angiogenic factors modulate gap junction function and connexin expression in endothelial cells, whereas endothelial connexins are involved in angiogenic tube formation and in the cell migration of endothelial cells. Several mechanisms, including gap junction function-dependent or -independent pathways, have been proposed. In particular, connexins might have the potential to regulate cell mechanics such as cell morphology, cell migration, and cellular stiffness that are dynamically changed during the angiogenic processes. Here, we review the implication for endothelial gap junctions and cellular mechanics in vascular angiogenesis.
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25
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Denis JF, Diagbouga MR, Molica F, Hautefort A, Linnerz T, Watanabe M, Lemeille S, Bertrand JY, Kwak BR. KLF4-Induced Connexin40 Expression Contributes to Arterial Endothelial Quiescence. Front Physiol 2019; 10:80. [PMID: 30809154 PMCID: PMC6379456 DOI: 10.3389/fphys.2019.00080] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 01/24/2019] [Indexed: 12/11/2022] Open
Abstract
Shear stress, a blood flow-induced frictional force, is essential in the control of endothelial cell (EC) homeostasis. High laminar shear stress (HLSS), as observed in straight parts of arteries, assures a quiescent non-activated endothelium through the induction of Krüppel-like transcription factors (KLFs). Connexin40 (Cx40)-mediated gap junctional communication is known to contribute to a healthy endothelium by propagating anti-inflammatory signals between ECs, however, the molecular basis of the transcriptional regulation of Cx40 as well as its downstream effectors remain poorly understood. Here, we show that flow-induced KLF4 regulated Cx40 expression in a mouse EC line. Chromatin immunoprecipitation in ECs revealed that KLF4 bound to three predicted KLF consensus binding sites in the Cx40 promoter. HLSS-dependent induction of Cx40 expression was confirmed in primary human ECs. The downstream effects of Cx40 modulation in ECs exposed to HLSS were elucidated by an unbiased transcriptomics approach. Cell cycle progression was identified as an important downstream target of Cx40 under HLSS. In agreement, an increase in the proportion of proliferating cell nuclear antigen (PCNA)-positive ECs and a decrease in the proportion of ECs in the G0/G1 phase were observed under HLSS after Cx40 silencing. Transfection of communication-incompetent HeLa cells with Cx40 demonstrated that the regulation of proliferation by Cx40 was not limited to ECs. Using a zebrafish model, we finally showed faster intersegmental vessel growth and branching into the dorsal longitudinal anastomotic vessel in embryos knock-out for the Cx40 orthologs Cx41.8 and Cx45.6. Most significant effects were observed in embryos with a mutant Cx41.8 encoding for a channel with reduced gap junctional function. Faster intersegmental vessel growth in Cx41.8 mutant embryos was associated with increased EC proliferation as assessed by PH3 immunostaining. Our data shows a novel evolutionary-conserved role of flow-driven KLF4-dependent Cx40 expression in endothelial quiescence that may be relevant for the control of atherosclerosis and diseases involving sprouting angiogenesis.
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Affiliation(s)
- Jean-François Denis
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
| | | | - Filippo Molica
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
| | - Aurélie Hautefort
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
| | - Tanja Linnerz
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
| | | | - Sylvain Lemeille
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
| | - Julien Y Bertrand
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
| | - Brenda R Kwak
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland.,Department of Medical Specializations - Cardiology, University of Geneva, Geneva, Switzerland
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Angiopoietin-1 Promotes the Integrity of Neovascularization in the Subcutaneous Matrigel of Type 1 Diabetic Rats. BIOMED RESEARCH INTERNATIONAL 2019; 2019:2016972. [PMID: 30729120 PMCID: PMC6343146 DOI: 10.1155/2019/2016972] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 12/30/2018] [Indexed: 12/21/2022]
Abstract
Objective This study aimed to investigate the effects of Ang-1 on neovascularization of diabetic organs by subcutaneous Matrigel angiogenesis model, established in type 1 diabetic rats. Methods Ang-1 adenoviral vector was constructed. The rat model was established by STZ and divided into four group. The Matrigel was inserted subcutaneously into the abdominal cavity of rats at 8 weeks, the treatment group was injected with Ang-1 adenovirus vector via tail vein, and the rats were sacrificed at 10 weeks. Neovascularization of Matrigel was observed with transmission electron microscopy. The marker of vascular endothelial cell and pericyte were detected by immunofluorescence. Immunohistochemical detection of the neovascular endothelial junction protein was performed. RT-PCR was used to determine protein expression of neovascular in Matrigel. Results Vascular cavity-like structure could be seen in subcutaneous Matrigel of diabetic rats, and the cavity was filled with a lot of red blood cells. Transmission electron microscopy showed that neovascular endothelial structure of the Matrigel was incomplete, while the Ang-1 treatment group had more vascular cavity-like structures, intact vascular endothelial structure, and reduced inflammatory cell infiltration in Matrigel. Additionally, the integrity of vascularization improved, and the marker of pericyte and the cell tight junctions protein was upregulated in Ang-1 treatment group. Conclusion Hyperglycemia could induce pathological angiogenesis in subcutaneous Matrigel of diabetic rats, and Ang-1 could upregulate the expression of intercellular junction protein in subcutaneous Matrigel of diabetic rats and promote the integrity of neovascularization in the subcutaneous Matrigel of diabetic rats.
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Pogoda K, Kameritsch P, Mannell H, Pohl U. Connexins in the control of vasomotor function. Acta Physiol (Oxf) 2019; 225:e13108. [PMID: 29858558 DOI: 10.1111/apha.13108] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 05/25/2018] [Accepted: 05/28/2018] [Indexed: 12/13/2022]
Abstract
Vascular endothelial cells, as well as smooth muscle cells, show heterogeneity with regard to their receptor expression and reactivity. For the vascular wall to act as a functional unit, the various cells' responses require integration. Such an integration is not only required for a homogeneous response of the vascular wall, but also for the vasomotor behaviour of consecutive segments of the microvascular arteriolar tree. As flow resistances of individual sections are connected in series, sections require synchronization and coordination to allow effective changes of conductivity and blood flow. A prerequisite for the local coordination of individual vascular cells and different sections of an arteriolar tree is intercellular communication. Connexins are involved in a dual manner in this coordination. (i) By forming gap junctions between cells, they allow an intercellular exchange of signalling molecules and electrical currents. In particular, the spread of electrical currents allows for coordination of cell responses over longer distances. (ii) Connexins are able to interact with other proteins to form signalling complexes. In this way, they can modulate and integrate individual cells' responses also in a channel-independent manner. This review outlines mechanisms allowing the vascular connexins to exert their coordinating function and to regulate the vasomotor reactions of blood vessels both locally, and in vascular networks. Wherever possible, we focus on the vasomotor behaviour of small vessels and arterioles which are the main vessels determining vascular resistance, blood pressure and local blood flow.
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Affiliation(s)
- K. Pogoda
- Walter-Brendel-Centre of Experimental Medicine; University Hospital; LMU Munich; Munich Germany
- Biomedical Center; Cardiovascular Physiology; LMU Munich; Munich Germany
- DZHK (German Center for Cardiovascular Research); Partner Site Munich Heart Alliance; Munich Germany
| | - P. Kameritsch
- Walter-Brendel-Centre of Experimental Medicine; University Hospital; LMU Munich; Munich Germany
- Biomedical Center; Cardiovascular Physiology; LMU Munich; Munich Germany
- DZHK (German Center for Cardiovascular Research); Partner Site Munich Heart Alliance; Munich Germany
| | - H. Mannell
- Walter-Brendel-Centre of Experimental Medicine; University Hospital; LMU Munich; Munich Germany
- Biomedical Center; Cardiovascular Physiology; LMU Munich; Munich Germany
| | - U. Pohl
- Walter-Brendel-Centre of Experimental Medicine; University Hospital; LMU Munich; Munich Germany
- Biomedical Center; Cardiovascular Physiology; LMU Munich; Munich Germany
- DZHK (German Center for Cardiovascular Research); Partner Site Munich Heart Alliance; Munich Germany
- Munich Cluster for Systems Neurology (SyNergy); Munich Germany
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