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Yamaguchi H, Gomez RA, Sequeira-Lopez MLS. Renin Cells, From Vascular Development to Blood Pressure Sensing. Hypertension 2023; 80:1580-1589. [PMID: 37313725 PMCID: PMC10526986 DOI: 10.1161/hypertensionaha.123.20577] [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] [Indexed: 06/15/2023]
Abstract
During embryonic and neonatal life, renin cells contribute to the assembly and branching of the intrarenal arterial tree. During kidney arteriolar development renin cells are widely distributed throughout the renal vasculature. As the arterioles mature, renin cells differentiate into smooth muscle cells, pericytes, and mesangial cells. In adult life, renin cells are confined to the tips of the renal arterioles, thus their name juxtaglomerular cells. Juxtaglomerular cells are sensors that release renin to control blood pressure and fluid-electrolyte homeostasis. Three major mechanisms control renin release: (1) β-adrenergic stimulation, (2) macula densa signaling, and (3) the renin baroreceptor, whereby a decrease in arterial pressure leads to increased renin release whereas an increase in pressure results in decrease renin release. Cells from the renin lineage exhibit plasticity in response to hypotension or hypovolemia, whereas relentless, chronic stimulation induces concentric arterial and arteriolar hypertrophy, leading to focal renal ischemia. The renin cell baroreceptor is a nuclear mechanotransducer within the renin cell that transmits external forces to the chromatin to regulate Ren1 gene expression. In addition to mechanotransduction, the pressure sensor of the renin cell may enlist additional molecules and structures including soluble signals and membrane proteins such as gap junctions and ion channels. How these various components integrate their actions to deliver the exact amounts of renin to meet the organism needs is unknown. This review describes the nature and origins of renin cells, their role in kidney vascular development and arteriolar diseases, and the current understanding of the blood pressure sensing mechanism.
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Affiliation(s)
- Hiroki Yamaguchi
- Department of Pediatrics, Child Health Research Center, University of Virginia School of Medicine, Charlottesville, Virginia
| | - R. Ariel Gomez
- Department of Pediatrics, Child Health Research Center, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Maria Luisa S. Sequeira-Lopez
- Department of Pediatrics, Child Health Research Center, University of Virginia School of Medicine, Charlottesville, Virginia
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2
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Márquez M, Muñoz M, Córdova A, Puebla M, Figueroa XF. Connexin 40-Mediated Regulation of Systemic Circulation and Arterial Blood Pressure. J Vasc Res 2023; 60:87-100. [PMID: 37331352 DOI: 10.1159/000531035] [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: 12/28/2022] [Accepted: 05/05/2023] [Indexed: 06/20/2023] Open
Abstract
Vascular system is a complex network in which different cell types and vascular segments must work in concert to regulate blood flow distribution and arterial blood pressure. Although paracrine/autocrine signaling is involved in the regulation of vasomotor tone, direct intercellular communication via gap junctions plays a central role in the control and coordination of vascular function in the microvascular network. Gap junctions are made up by connexin (Cx) proteins, and among the four Cxs expressed in the cardiovascular system (Cx37, Cx40, Cx43, and Cx45), Cx40 has emerged as a critical signaling pathway in the vessel wall. This Cx is predominantly found in the endothelium, but it is involved in the development of the cardiovascular system and in the coordination of endothelial and smooth muscle cell function along the length of the vessels. In addition, Cx40 participates in the control of vasomotor tone through the transmission of electrical signals from the endothelium to the underlying smooth muscle and in the regulation of arterial blood pressure by renin-angiotensin system in afferent arterioles. In this review, we discuss the participation of Cx40-formed channels in the development of cardiovascular system, control and coordination of vascular function, and regulation of arterial blood pressure.
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Affiliation(s)
- Mónica Márquez
- Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Matías Muñoz
- Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alexandra Córdova
- Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Mariela Puebla
- Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Xavier F Figueroa
- Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
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3
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Kenney HM, Peng Y, de Mesy Bentley KL, Xing L, Ritchlin CT, Schwarz EM. The Enigmas of Lymphatic Muscle Cells: Where Do They Come From, How Are They Maintained, and Can They Regenerate? Curr Rheumatol Rev 2023; 19:246-259. [PMID: 36705238 PMCID: PMC10257750 DOI: 10.2174/1573397119666230127144711] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 10/29/2022] [Accepted: 12/02/2022] [Indexed: 01/28/2023]
Abstract
Lymphatic muscle cell (LMC) contractility and coverage of collecting lymphatic vessels (CLVs) are integral to effective lymphatic drainage and tissue homeostasis. In fact, defects in lymphatic contractility have been identified in various conditions, including rheumatoid arthritis, inflammatory bowel disease, and obesity. However, the fundamental role of LMCs in these pathologic processes is limited, primarily due to the difficulty in directly investigating the enigmatic nature of this poorly characterized cell type. LMCs are a unique cell type that exhibit dual tonic and phasic contractility with hybrid structural features of both vascular smooth muscle cells (VSMCs) and cardiac myocytes. While advances have been made in recent years to better understand the biochemistry and function of LMCs, central questions regarding their origins, investiture into CLVs, and homeostasis remain unanswered. To summarize these discoveries, unexplained experimental results, and critical future directions, here we provide a focused review of current knowledge and open questions related to LMC progenitor cells, recruitment, maintenance, and regeneration. We also highlight the high-priority research goal of identifying LMC-specific genes towards genetic conditional- inducible in vivo gain and loss of function studies. While our interest in LMCs has been focused on understanding lymphatic dysfunction in an arthritic flare, these concepts are integral to the broader field of lymphatic biology, and have important potential for clinical translation through targeted therapeutics to control lymphatic contractility and drainage.
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Grants
- R01AG059775,R01AG059775,R01AG059775 NIA NIH HHS
- R01AR056702,R01AR069000,T32AR076950,P30AR069655,R01AR056702,R01AR069000,P30AR069655,T32AR076950,R01AR056702,R01AR069000,T32AR076950,P30AR069655 NIAMS NIH HHS
- P30 AR069655 NIAMS NIH HHS
- R01 AR069000 NIAMS NIH HHS
- T32 GM007356 NIGMS NIH HHS
- R01 AG059775 NIA NIH HHS
- T32GM007356,T32GM007356,T32GM007356,T32GM007356 NIGMS NIH HHS
- T32 AR076950 NIAMS NIH HHS
- R01 AR056702 NIAMS NIH HHS
- F30 AG076326 NIA NIH HHS
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Affiliation(s)
- H. Mark Kenney
- Center for Musculoskeletal Research, University of Rochester Medical Center, 601 Elmwood Ave, Box 665, Rochester, NY, 14642, USA
- Department of Pathology & Laboratory Medicine, University of Rochester Medical Center, Rochester, NY, USA
| | - Yue Peng
- Center for Musculoskeletal Research, University of Rochester Medical Center, 601 Elmwood Ave, Box 665, Rochester, NY, 14642, USA
- Department of Pathology & Laboratory Medicine, University of Rochester Medical Center, Rochester, NY, USA
| | - Karen L. de Mesy Bentley
- Center for Musculoskeletal Research, University of Rochester Medical Center, 601 Elmwood Ave, Box 665, Rochester, NY, 14642, USA
- Department of Pathology & Laboratory Medicine, University of Rochester Medical Center, Rochester, NY, USA
- Department of Orthopaedics, University of Rochester Medical Center, Rochester, NY, USA
| | - Lianping Xing
- Center for Musculoskeletal Research, University of Rochester Medical Center, 601 Elmwood Ave, Box 665, Rochester, NY, 14642, USA
- Department of Pathology & Laboratory Medicine, University of Rochester Medical Center, Rochester, NY, USA
| | - Christopher T. Ritchlin
- Center for Musculoskeletal Research, University of Rochester Medical Center, 601 Elmwood Ave, Box 665, Rochester, NY, 14642, USA
- Department of Medicine, Division of Allergy, Immunology, Rheumatology, University of Rochester Medical Center, Rochester, NY, USA
| | - Edward M. Schwarz
- Center for Musculoskeletal Research, University of Rochester Medical Center, 601 Elmwood Ave, Box 665, Rochester, NY, 14642, USA
- Department of Pathology & Laboratory Medicine, University of Rochester Medical Center, Rochester, NY, USA
- Department of Medicine, Division of Allergy, Immunology, Rheumatology, University of Rochester Medical Center, Rochester, NY, USA
- Department of Orthopaedics, University of Rochester Medical Center, Rochester, NY, USA
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4
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Saito N, Toyoda M, Kondo M, Abe M, Sanechika N, Kimura M, Sawada K, Fukagawa M. Regulation of Renin Expression by Β1-Integrin in As4.1 Juxtaglomerular Line Cells. Biomedicines 2023; 11:biomedicines11020501. [PMID: 36831037 PMCID: PMC9953579 DOI: 10.3390/biomedicines11020501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 02/06/2023] [Accepted: 02/08/2023] [Indexed: 02/12/2023] Open
Abstract
(1) Background: Renal dysfunction and hypertension are mutually aggravating factors; however, the details of their interaction remain unclear. In a study using renal tissue from diabetic rats, we found that β1-integrin, a cell-substrate adhesion molecule, is specifically phosphorylated in juxtaglomerular cells that secrete renin, a blood pressure regulator. (2) Methods: A mouse juxtaglomerular cell line (As4.1 cells) was used for the following experiments: drug-induced promotion of β1-integrin phosphorylation/dephosphorylation; knockdown of β1-integrin and the cell adhesion molecule connexin-40 (a candidate for the main body of baroreceptor); and pressurization to atmospheric pressure + 100 mmHg. culture in hypotonic liquid medium. The expression of renin under these conditions was measured by qRT-PCR. (3) Results: Phosphorylation of β1-integrin suppressed the expression of renin, while dephosphorylation conversely promoted it. β1-integrin and connexin-40 knockdown both promoted the expression of renin. Pneumatic pressurization and hypotonic medium culture both decreased the expression of renin, which was restored by the knockdown of β1-integrin. (4) Conclusions: β1-integrin plays an inhibitory role in the regulation of the expression of renin, which may be controlled by phosphorylation and dephosphorylation. It is hypothesized that β1-integrin and other adhesion factors regulate the expression of renin by altering the sensitivity of baroreceptors on the plasma membrane.
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Affiliation(s)
| | - Masao Toyoda
- Correspondence: ; Tel.: +81-463-93-1121 (ext. 2490)
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Hypertensive Nephropathy: Unveiling the Possible Involvement of Hemichannels and Pannexons. Int J Mol Sci 2022; 23:ijms232415936. [PMID: 36555574 PMCID: PMC9785367 DOI: 10.3390/ijms232415936] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 12/09/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
Hypertension is one of the most common risk factors for developing chronic cardiovascular diseases, including hypertensive nephropathy. Within the glomerulus, hypertension causes damage and activation of mesangial cells (MCs), eliciting the production of large amounts of vasoactive and proinflammatory agents. Accordingly, the activation of AT1 receptors by the vasoactive molecule angiotensin II (AngII) contributes to the pathogenesis of renal damage, which is mediated mostly by the dysfunction of intracellular Ca2+ ([Ca2+]i) signaling. Similarly, inflammation entails complex processes, where [Ca2+]i also play crucial roles. Deregulation of this second messenger increases cell damage and promotes fibrosis, reduces renal blood flow, and impairs the glomerular filtration barrier. In vertebrates, [Ca2+]i signaling depends, in part, on the activity of two families of large-pore channels: hemichannels and pannexons. Interestingly, the opening of these channels depends on [Ca2+]i signaling. In this review, we propose that the opening of channels formed by connexins and/or pannexins mediated by AngII induces the ATP release to the extracellular media, with the subsequent activation of purinergic receptors. This process could elicit Ca2+ overload and constitute a feed-forward mechanism, leading to kidney damage.
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6
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King DR, Sedovy MW, Eaton X, Dunaway LS, Good ME, Isakson BE, Johnstone SR. Cell-To-Cell Communication in the Resistance Vasculature. Compr Physiol 2022; 12:3833-3867. [PMID: 35959755 DOI: 10.1002/cphy.c210040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The arterial vasculature can be divided into large conduit arteries, intermediate contractile arteries, resistance arteries, arterioles, and capillaries. Resistance arteries and arterioles primarily function to control systemic blood pressure. The resistance arteries are composed of a layer of endothelial cells oriented parallel to the direction of blood flow, which are separated by a matrix layer termed the internal elastic lamina from several layers of smooth muscle cells oriented perpendicular to the direction of blood flow. Cells within the vessel walls communicate in a homocellular and heterocellular fashion to govern luminal diameter, arterial resistance, and blood pressure. At rest, potassium currents govern the basal state of endothelial and smooth muscle cells. Multiple stimuli can elicit rises in intracellular calcium levels in either endothelial cells or smooth muscle cells, sourced from intracellular stores such as the endoplasmic reticulum or the extracellular space. In general, activation of endothelial cells results in the production of a vasodilatory signal, usually in the form of nitric oxide or endothelial-derived hyperpolarization. Conversely, activation of smooth muscle cells results in a vasoconstriction response through smooth muscle cell contraction. © 2022 American Physiological Society. Compr Physiol 12: 1-35, 2022.
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Affiliation(s)
- D Ryan King
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Center for Vascular and Heart Research, Virginia Tech, Roanoke, Virginia, USA
| | - Meghan W Sedovy
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Center for Vascular and Heart Research, Virginia Tech, Roanoke, Virginia, USA.,Translational Biology, Medicine, and Health Graduate Program, Virginia Tech, Blacksburg, Virginia, USA
| | - Xinyan Eaton
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Center for Vascular and Heart Research, Virginia Tech, Roanoke, Virginia, USA
| | - Luke S Dunaway
- Robert M. Berne Cardiovascular Research Centre, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Miranda E Good
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, Massachusetts, USA
| | - Brant E Isakson
- Robert M. Berne Cardiovascular Research Centre, University of Virginia School of Medicine, Charlottesville, Virginia, USA.,Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Scott R Johnstone
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Center for Vascular and Heart Research, Virginia Tech, Roanoke, Virginia, USA.,Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
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7
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Lin H, Geurts F, Hassler L, Batlle D, Mirabito Colafella KM, Denton KM, Zhuo JL, Li XC, Ramkumar N, Koizumi M, Matsusaka T, Nishiyama A, Hoogduijn MJ, Hoorn EJ, Danser AHJ. Kidney Angiotensin in Cardiovascular Disease: Formation and Drug Targeting. Pharmacol Rev 2022; 74:462-505. [PMID: 35710133 PMCID: PMC9553117 DOI: 10.1124/pharmrev.120.000236] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The concept of local formation of angiotensin II in the kidney has changed over the last 10-15 years. Local synthesis of angiotensinogen in the proximal tubule has been proposed, combined with prorenin synthesis in the collecting duct. Binding of prorenin via the so-called (pro)renin receptor has been introduced, as well as megalin-mediated uptake of filtered plasma-derived renin-angiotensin system (RAS) components. Moreover, angiotensin metabolites other than angiotensin II [notably angiotensin-(1-7)] exist, and angiotensins exert their effects via three different receptors, of which angiotensin II type 2 and Mas receptors are considered renoprotective, possibly in a sex-specific manner, whereas angiotensin II type 1 (AT1) receptors are believed to be deleterious. Additionally, internalized angiotensin II may stimulate intracellular receptors. Angiotensin-converting enzyme 2 (ACE2) not only generates angiotensin-(1-7) but also acts as coronavirus receptor. Multiple, if not all, cardiovascular diseases involve the kidney RAS, with renal AT1 receptors often being claimed to exert a crucial role. Urinary RAS component levels, depending on filtration, reabsorption, and local release, are believed to reflect renal RAS activity. Finally, both existing drugs (RAS inhibitors, cyclooxygenase inhibitors) and novel drugs (angiotensin receptor/neprilysin inhibitors, sodium-glucose cotransporter-2 inhibitors, soluble ACE2) affect renal angiotensin formation, thereby displaying cardiovascular efficacy. Particular in the case of the latter three, an important question is to what degree they induce renoprotection (e.g., in a renal RAS-dependent manner). This review provides a unifying view, explaining not only how kidney angiotensin formation occurs and how it is affected by drugs but also why drugs are renoprotective when altering the renal RAS. SIGNIFICANCE STATEMENT: Angiotensin formation in the kidney is widely accepted but little understood, and multiple, often contrasting concepts have been put forward over the last two decades. This paper offers a unifying view, simultaneously explaining how existing and novel drugs exert renoprotection by interfering with kidney angiotensin formation.
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Affiliation(s)
- Hui Lin
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Frank Geurts
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Luise Hassler
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Daniel Batlle
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Katrina M Mirabito Colafella
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Kate M Denton
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Jia L Zhuo
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Xiao C Li
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Nirupama Ramkumar
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Masahiro Koizumi
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Taiji Matsusaka
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Akira Nishiyama
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Martin J Hoogduijn
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - Ewout J Hoorn
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
| | - A H Jan Danser
- Division of Pharmacology and Vascular Medicine (H.L., A.H.J.D.) and Division of Nephrology and Transplantation (F.G., M.J.H., E.J.H.), Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands; Northwestern University Feinberg School of Medicine, Chicago, Illinois (L.H., D.B.); Monash University, Melbourne, Australia (K.M.M.C., K.M.D.); Tulane University School of Medicine, New Orleans, Louisiana (J.L.Z., X.C.L.); Division of Nephrology and Hypertension, University of Utah School of Medicine, Salt Lake City, Utah (N.R.); Division of Nephrology, Endocrinology, and Metabolism (M.K.) and Institute of Medical Sciences and Department of Basic Medicine (M.K., T.M.), Tokai University School of Medicine, Isehara, Japan; and Department of Pharmacology, Faculty of Medicine, Kagawa University, Miki-cho, Kita-gun, Japan (A.N.)
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8
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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: 1.0] [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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9
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Broeker KAE, Schrankl J, Fuchs MAA, Kurtz A. Flexible and multifaceted: the plasticity of renin-expressing cells. Pflugers Arch 2022; 474:799-812. [PMID: 35511367 PMCID: PMC9338909 DOI: 10.1007/s00424-022-02694-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 04/21/2022] [Accepted: 04/22/2022] [Indexed: 12/14/2022]
Abstract
The protease renin, the key enzyme of the renin–angiotensin–aldosterone system, is mainly produced and secreted by juxtaglomerular cells in the kidney, which are located in the walls of the afferent arterioles at their entrance into the glomeruli. When the body’s demand for renin rises, the renin production capacity of the kidneys commonly increases by induction of renin expression in vascular smooth muscle cells and in extraglomerular mesangial cells. These cells undergo a reversible metaplastic cellular transformation in order to produce renin. Juxtaglomerular cells of the renin lineage have also been described to migrate into the glomerulus and differentiate into podocytes, epithelial cells or mesangial cells to restore damaged cells in states of glomerular disease. More recently, it could be shown that renin cells can also undergo an endocrine and metaplastic switch to erythropoietin-producing cells. This review aims to describe the high degree of plasticity of renin-producing cells of the kidneys and to analyze the underlying mechanisms.
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Affiliation(s)
- Katharina A E Broeker
- Institute of Physiology, University of Regensburg, Universitätsstraβe 31, D-93053 , Regensburg, Germany.
| | - Julia Schrankl
- Institute of Physiology, University of Regensburg, Universitätsstraβe 31, D-93053 , Regensburg, Germany
| | - Michaela A A Fuchs
- Institute of Physiology, University of Regensburg, Universitätsstraβe 31, D-93053 , Regensburg, Germany
| | - Armin Kurtz
- Institute of Physiology, University of Regensburg, Universitätsstraβe 31, D-93053 , Regensburg, Germany
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10
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Geis L, Boudriot FF, Wagner C. Connexin mRNA distribution in adult mouse kidneys. Pflugers Arch 2021; 473:1737-1747. [PMID: 34365513 PMCID: PMC8528753 DOI: 10.1007/s00424-021-02608-0] [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: 04/27/2021] [Revised: 07/18/2021] [Accepted: 07/22/2021] [Indexed: 11/25/2022]
Abstract
Kidneys are thought to express eight different connexin isoforms (i.e., Cx 26, 30, 32, 37, 40, 43, 45, and 46), which form either hemichannels or gap junctions serving to intercellular communication and functional synchronization. Proper function of connexins has already been shown to be crucial for regulation of renal hemodynamics and renin secretion, and there is also growing evidence for connexins to play a role in pathologic conditions such as renal fibrosis or diabetic nephropathy. Therefore, exact intrarenal localization of the different connexin isoforms gains particular interest. Until now intrarenal expression of connexins has mainly been examined by immunohistochemistry, which in part generated conflicting results depending on antibodies and fixation protocols used. In this work, we used fluorescent RNAscope as an alternative technical approach to localize renal connexin mRNAs in healthy mouse kidneys. Addition of RNAscope probes for cell type specific mRNAs was used to assign connexin mRNA signals to specific cell types. We hereby found Cx26 mRNA strongly expressed in proximal tubules, Cx30 mRNA was selectively detected in the urothelium, and Cx32 mRNA was found in proximal tubules and to a lesser extent also in collecting ducts. Cx37 mRNA was mainly associated with vascular endothelium, Cx40 mRNA was largely found in glomerular mesangial and less in vascular endothelial cells, Cx43 mRNA was sparsely expressed by interstitial cells of all kidney zones, and Cx45 mRNA was predominantly found in smooth muscle cell layers of both blood vessels and ureter as well as in mesangial and interstitial (fibroblastic) cells. Cx46 mRNA could not be detected. In summary our results essentially confirm previous data on connexin expression in the renal vasculature and in glomeruli. In addition, they demonstrate strong connexin gene expression in proximal tubules, and they suggest significant connexin expression in resident tubulointerstitial cells.
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Affiliation(s)
- Lisa Geis
- Department of Nephrology, University Hospital Regensburg, Regensburg, Germany.
| | | | - Charlotte Wagner
- Institute of Physiology, University of Regensburg, Regensburg, Germany
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11
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Abstract
Renin cells are essential for survival perfected throughout evolution to ensure normal development and defend the organism against a variety of homeostatic threats. During embryonic and early postnatal life, they are progenitors that participate in the morphogenesis of the renal arterial tree. In adult life, they are capable of regenerating injured glomeruli, control blood pressure, fluid-electrolyte balance, tissue perfusion, and in turn, the delivery of oxygen and nutrients to cells. Throughout life, renin cell descendants retain the plasticity or memory to regain the renin phenotype when homeostasis is threatened. To perform all of these functions and maintain well-being, renin cells must regulate their identity and fate. Here, we review the major mechanisms that control the differentiation and fate of renin cells, the chromatin events that control the memory of the renin phenotype, and the major pathways that determine their plasticity. We also examine how chronic stimulation of renin cells alters their fate leading to the development of a severe and concentric hypertrophy of the intrarenal arteries and arterioles. Lastly, we provide examples of additional changes in renin cell fate that contribute to equally severe kidney disorders.
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Affiliation(s)
- Maria Luisa S. Sequeira-Lopez
- Departments of Pediatrics an Biology, Child Health Research Center, University of Virginia School of Medicine, Charlottesville, Virginia
| | - R. Ariel Gomez
- Departments of Pediatrics an Biology, Child Health Research Center, University of Virginia School of Medicine, Charlottesville, Virginia
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12
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Klotho supplementation attenuates blood pressure and albuminuria in murine model of IgA nephropathy. J Hypertens 2021; 39:1567-1576. [PMID: 33758157 DOI: 10.1097/hjh.0000000000002845] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND Klotho interacts with various membrane proteins, such as transforming growth factor-β (TGFβ) and insulin-like growth factor (IGF) receptors. The renal expression of klotho is diminished in chronic kidney disease. METHOD In this study, we assessed the effects of klotho supplementation on a murine model of IgA nephropathy. Twenty-four-week-old hyper serum IgA (HIGA) mice were subcutaneously injected daily with recombinant human klotho protein (20 μg/kg per day) or the vehicle. After 2 months, the mice were killed using an anesthesia overdose and their kidneys were harvested for analysis. RESULTS Supplementation of exogenous klotho protein reduced SBP, albuminuria, 8-epi-prostaglandin F2α excretion, glomerular filtration rate, renal angiotensin II concentration, and angiotensinogen expression in HIGA mice. Additionally, it enhanced renal expression of superoxide dismutase (SOD) and renal klotho itself. The findings using laser-manipulated microdissection demonstrated that klotho supplementation reduced the glomerular expression of TGFβ, fibronectin, and IGF, and increased the glomerular expression of connexin (Cx) 40. CONCLUSION These results indicate that klotho supplementation reduces blood pressure by suppressing the renin--angiotensin system in HIGA mice. Klotho inhibits IGF signaling to preserve glomerular Cx40 levels, ameliorating albuminuria in HIGA mice. Klotho protein supplementation attenuates mesangial expansion by inhibiting TGFβ signaling in HIGA mice.
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13
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Schmidt K, de Wit C. Endothelium-Derived Hyperpolarizing Factor and Myoendothelial Coupling: The in vivo Perspective. Front Physiol 2021; 11:602930. [PMID: 33424626 PMCID: PMC7786115 DOI: 10.3389/fphys.2020.602930] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 11/30/2020] [Indexed: 12/11/2022] Open
Abstract
The endothelium controls vascular tone adopting blood flow to tissue needs. It releases chemical mediators [e.g., nitric oxide (NO), prostaglandins (PG)] and exerts appreciable dilation through smooth muscle hyperpolarization, thus termed endothelium-dependent hyperpolarization (EDH). Initially, EDH was attributed to release of a factor, but later it was suggested that smooth muscle hyperpolarization might be derived from radial spread of an initial endothelial hyperpolarization through heterocellular channels coupling these vascular cells. The channels are indeed present and formed by connexins that enrich in gap junctions (GJ). In vitro data suggest that myoendothelial coupling underlies EDH-type dilations as evidenced by blocking experiments as well as simultaneous, merely identical membrane potential changes in endothelial and smooth muscle cells (SMCs), which is indicative of coupling through ohmic resistors. However, connexin-deficient animals do not display any attenuation of EDH-type dilations in vivo, and endothelial and SMCs exhibit distinct and barely superimposable membrane potential changes exerted by different means in vivo. Even if studied in the exact same artery EDH-type dilation exhibits distinct features in vitro and in vivo: in isometrically mounted vessels, it is rather weak and depends on myoendothelial coupling through connexin40 (Cx40), whereas in vivo as well as in vitro under isobaric conditions it is powerful and independent of myoendothelial coupling through Cx40. It is concluded that EDH-type dilations are distinct and a significant dependence on myoendothelial coupling in vitro does not reflect the situation under physiologic conditions in vivo. Myoendothelial coupling may act as a backup mechanism that is uncovered in the absence of the powerful EDH-type response and possibly reflects a situation in a pathophysiologic environment.
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Affiliation(s)
- Kjestine Schmidt
- Institut für Physiologie, Universität zu Lübeck, Lübeck, Germany.,Deutsches Zentrum für Herz-Kreislauf-Forschung (DZHK) e.V. (German Center for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Lübeck, Germany
| | - Cor de Wit
- Institut für Physiologie, Universität zu Lübeck, Lübeck, Germany.,Deutsches Zentrum für Herz-Kreislauf-Forschung (DZHK) e.V. (German Center for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Lübeck, Germany
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14
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Kosovic I, Filipovic N, Benzon B, Bocina I, Glavina Durdov M, Vukojevic K, Saraga M, Saraga-Babic M. Connexin Signaling in the Juxtaglomerular Apparatus (JGA) of Developing, Postnatal Healthy and Nephrotic Human Kidneys. Int J Mol Sci 2020; 21:E8349. [PMID: 33172216 PMCID: PMC7664435 DOI: 10.3390/ijms21218349] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/04/2020] [Accepted: 11/05/2020] [Indexed: 12/31/2022] Open
Abstract
Our study analyzed the expression pattern of different connexins (Cxs) and renin positive cells in the juxtaglomerular apparatus (JGA) of developing, postnatal healthy human kidneys and in nephrotic syndrome of the Finnish type (CNF), by using double immunofluorescence, electron microscopy and statistical measuring. The JGA contained several cell types connected by Cxs, and consisting of macula densa, extraglomerular mesangium (EM) and juxtaglomerular cells (JC), which release renin involved in renin-angiotensin- aldosteron system (RAS) of arterial blood pressure control. During JGA development, strong Cx40 expression gradually decreased, while expression of Cx37, Cx43 and Cx45 increased, postnatally showing more equalized expression patterning. In parallel, initially dispersed renin cells localized to JGA, and greatly increased expression in postnatal kidneys. In CNF kidneys, increased levels of Cx43, Cx37 and Cx45 co-localized with accumulations of renin cells in JGA. Additionally, they reappeared in extraglomerular mesangial cells, indicating association between return to embryonic Cxs patterning and pathologically changed kidney tissue. Based on the described Cxs and renin expression patterning, we suggest involvement of Cx40 primarily in the formation of JGA in developing kidneys, while Cx37, Cx43 and Cx45 might participate in JGA signal transfer important for postnatal maintenance of kidney function and blood pressure control.
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Affiliation(s)
- Ivona Kosovic
- Department of Anatomy, Histology and Embryology, School of Medicine, University of Split, 21000 Split, Croatia; (I.K.); (N.F.); (B.B.); (K.V.)
| | - Natalija Filipovic
- Department of Anatomy, Histology and Embryology, School of Medicine, University of Split, 21000 Split, Croatia; (I.K.); (N.F.); (B.B.); (K.V.)
| | - Benjamin Benzon
- Department of Anatomy, Histology and Embryology, School of Medicine, University of Split, 21000 Split, Croatia; (I.K.); (N.F.); (B.B.); (K.V.)
| | - Ivana Bocina
- Department of Biology, Faculty of Science, University of Split, 21000 Split, Croatia;
| | - Merica Glavina Durdov
- Department of Pathology, University Hospital in Split, School of Medicine, University of Split, 21000 Split, Croatia;
| | - Katarina Vukojevic
- Department of Anatomy, Histology and Embryology, School of Medicine, University of Split, 21000 Split, Croatia; (I.K.); (N.F.); (B.B.); (K.V.)
| | - Marijan Saraga
- Department of Paediatrics, University Hospital in Split, School of Medicine, University of Split, 21000 Split, Croatia;
| | - Mirna Saraga-Babic
- Department of Anatomy, Histology and Embryology, School of Medicine, University of Split, 21000 Split, Croatia; (I.K.); (N.F.); (B.B.); (K.V.)
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15
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Regulation of connexins genes expression contributes to reestablishes tissue homeostasis in a renovascular hypertension model. Heliyon 2020; 6:e05406. [PMID: 33163681 PMCID: PMC7609588 DOI: 10.1016/j.heliyon.2020.e05406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 09/22/2020] [Accepted: 10/28/2020] [Indexed: 11/24/2022] Open
Abstract
Connexins (Cx) are essential for cardiovascular regulation and maintenance of cardio-renal response involving the natriuretic peptide family. Changes in the expression of connexins promote intercellular communication dysfunction and may induce hypertension, atherosclerosis, and several other vascular diseases. This study analyzed the expression of the genes involved in the renin-angiotensin system (RAS) and the relation of the connexins gene expression with the renovascular hypertension 2K1C in different tissues. The insertion of a silver clip induced renovascular hypertension 2K1C into the left renal artery. Biochemical measurements were made using commercial kits. Gene expression was evaluated in the liver, heart, and kidneys by RT-PCR. The genes investigated were LDLr, Hmgcr, Agt, Ren, Ace, Agtr1a, Anp, Bnp, Npr1, Cx26, Cx32, Cx37, Cx40 and Cx43. All genes involved in the RAS presented increased transcriptional levels in the 2K1C group, except hepatic Agt. The natriuretic peptides (Anp; Bnp) and the receptor genes (Npr1) appeared to increase in the heart, however, Npr1 decreased in the kidneys. In hepatic tissue, hypertension promoted increased expression of Cx32, Cx37, and Cx40 genes however, Cx26 and Cx43 genes were not influenced. Expression was upregulated for Cx37 and Cx43 in cardiac tissue in the 2K1C group, but Cx40 did not demonstrate any difference between groups. The stenotic kidney showed an upregulated expression for Cx37 vs Sham and contralateral kidney, although Cx40 and Cx43 were downregulated. Hypertension did not modify the transcriptional expression of Cx26 and Cx32. Therefore, this study indicated that RAS and cardiac response were regulated transcriptionally by renovascular hypertension 2K1C. Moreover, the results of connexin gene expression demonstrated differential transcriptional regulation in different tissues studied and suggest a relationship between cardiac and renal physiological changes as an adaptive mechanism to the hypertensive state.
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16
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Møller S, Jacobsen JCB, Holstein-Rathlou NH, Sorensen CM. Lack of Connexins 40 and 45 Reduces Local and Conducted Vasoconstrictor Responses in the Murine Afferent Arterioles. Front Physiol 2020; 11:961. [PMID: 32848881 PMCID: PMC7431600 DOI: 10.3389/fphys.2020.00961] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 07/15/2020] [Indexed: 01/07/2023] Open
Abstract
The juxtaglomerular apparatus (JGA) is an essential structure in the regulation of renal function. The JGA embodies two major functions: tubuloglomerular feedback (TGF) and renin secretion. TGF is one of the mechanisms mediating renal autoregulation. It is initiated by an increase in tubular NaCl concentration at the macula densa cells. This induces a local afferent arteriolar vasoconstriction and a conducted response that can be measured several 100 μm upstream from the juxtaglomerular segment. This spread of the vasomotor response into the surrounding vasculature likely plays a key role in renal autoregulation, and it requires the presence of gap junctions, intercellular pores based on connexin (Cx) proteins. Several Cx isoforms are expressed in the JGA and in the arteriolar wall. Disruption of this communication pathway is associated with reduced TGF, dysregulation of renin secretion, and hypertension. We examine if the absence of Cx40 or Cx45, expressed in the endothelial and vascular smooth muscle cells respectively, attenuates afferent arteriolar local and conducted vasoconstriction. Afferent arterioles from wildtype and Cx-deficient mice (Cx40 and Cx45) were studied using the isolated perfused juxtamedullary nephron preparation. Vasoconstriction was induced via electrical pulse stimulation at the glomerular entrance. Inner afferent arteriolar diameter was measured locally and upstream to evaluate conducted vasoconstriction. Electrical stimulation induced local vasoconstriction in all groups. The local vasoconstriction was significantly smaller when Cx40 was absent. The vasoconstriction decreased in magnitude with increasing distance from the stimulation site. In both Cx40 and Cx45 deficient mice, the vasoconstriction conducted a shorter distance along the vessel compared to wild-type mice. In Cx40 deficient arterioles, this may be caused by a smaller local vasoconstriction. Collectively, these findings imply that Cx40 and Cx45 are central for normal vascular reactivity and, therefore, likely play a key role in TGF-induced regulation of afferent arteriolar resistance.
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Affiliation(s)
- Sophie Møller
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens Christian Brings Jacobsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Niels-Henrik Holstein-Rathlou
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Charlotte M Sorensen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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17
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Connexin Hemichannels Contribute to the Activation of cAMP Signaling Pathway and Renin Production. Int J Mol Sci 2020; 21:ijms21124462. [PMID: 32585970 PMCID: PMC7353028 DOI: 10.3390/ijms21124462] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 06/18/2020] [Accepted: 06/22/2020] [Indexed: 01/06/2023] Open
Abstract
Connexin hemichannels play an important role in the control of cellular signaling and behaviors. Given that lowering extracellular Ca2+, a condition that activates hemichannels, is a well-characterized stimulator of renin in juxtaglomerular cells, we, therefore, tested a potential implication of hemichannels in the regulation of renin in As4.1 renin-secreting cells. Lowering extracellular Ca2+ induced hemichannel opening, which was associated with cAMP signaling pathway activation and increased renin production. Blockade of hemichannels with inhibitors or downregulation of Cxs with siRNAs abrogated the activation of cAMP pathway and the elevation of renin. Further analysis revealed that cAMP pathway activation was blocked by adenylyl cyclase inhibitor SQ 22536, suggesting an implication of adenyl cyclase. Furthermore, the participation of hemichannels in the activation of the cAMP signaling pathway was also observed in a renal tubular epithelial cell line NRK. Collectively, our results characterized the hemichannel opening as a presently unrecognized molecular event involved in low Ca2+-elicited activation of cAMP pathway and renin production. Our findings thus provide novel mechanistic insights into the low Ca2+-initiated cell responses. Given the importance of cAMP signaling pathway in the control of multiple cellular functions, our findings also highlight the importance of Cx-forming channels in various pathophysiological situations.
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18
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Steglich A, Hickmann L, Linkermann A, Bornstein S, Hugo C, Todorov VT. Beyond the Paradigm: Novel Functions of Renin-Producing Cells. Rev Physiol Biochem Pharmacol 2020; 177:53-81. [PMID: 32691160 DOI: 10.1007/112_2020_27] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The juxtaglomerular renin-producing cells (RPC) of the kidney are referred to as the major source of circulating renin. Renin is the limiting factor in renin-angiotensin system (RAS), which represents a proteolytic cascade in blood plasma that plays a central role in the regulation of blood pressure. Further cells disseminated in the entire organism express renin at a low level as part of tissue RASs, which are thought to locally modulate the effects of systemic RAS. In recent years, it became increasingly clear that the renal RPC are involved in developmental, physiological, and pathophysiological processes outside RAS. Based on recent experimental evidence, a novel concept emerges postulating that next to their traditional role, the RPC have non-canonical RAS-independent progenitor and renoprotective functions. Moreover, the RPC are part of a widespread renin lineage population, which may act as a global stem cell pool coordinating homeostatic, stress, and regenerative responses throughout the organism. This review focuses on the RAS-unrelated functions of RPC - a dynamic research area that increasingly attracts attention.
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Affiliation(s)
- Anne Steglich
- Experimental Nephrology, Division of Nephrology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - Linda Hickmann
- Experimental Nephrology, Division of Nephrology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - Andreas Linkermann
- Experimental Nephrology, Division of Nephrology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - Stefan Bornstein
- Experimental Nephrology, Division of Nephrology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - Christian Hugo
- Experimental Nephrology, Division of Nephrology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - Vladimir T Todorov
- Experimental Nephrology, Division of Nephrology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, TU Dresden, Dresden, Germany.
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19
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Sorensen CM, Cupples WA. Myoendothelial communication in the renal vasculature and the impact of drugs used clinically to treat hypertension. Curr Opin Pharmacol 2019; 45:49-56. [PMID: 31071677 DOI: 10.1016/j.coph.2019.04.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 04/04/2019] [Indexed: 12/11/2022]
Abstract
The renal vasculature has many peculiarities including highly irregular branching. Renal blood flow must sustain adequate perfusion and maintain a high glomerular filtration. Renal autoregulation helps control renal blood flow. The local autoregulatory mechanism, tubuloglomerular feedback, elicits a vasoconstriction that can be found not only in neighboring nephrons but over large areas of the kidney indicating that the renal vasculature supports strong conduction of vascular responses. The basis for conduction is intercellular communication through gap junctions. The endothelium is strongly coupled and serves as a vascular conduction highway leading the signal to the vascular smooth muscle cells through myoendothelial coupling. Extensive intercellular coupling is also found in renin secreting cells where gap junctions seem to tie the cells together to improve control of renin secretion. Lack of coupling leads to dysregulation of renin secretion and hypertension. However, the activity of the renin-angiotensin system also controls gap junction expression in the kidney. Treatment reducing angiotensin II activity, as used in hypertension treatment, can affect expression of renal and vascular gap junction.
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Affiliation(s)
| | - William A Cupples
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Canada
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20
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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: 1.8] [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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21
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Hernández-Guerra M, Hadjihambi A, Jalan R. Gap junctions in liver disease: Implications for pathogenesis and therapy. J Hepatol 2019; 70:759-772. [PMID: 30599172 DOI: 10.1016/j.jhep.2018.12.023] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Revised: 12/03/2018] [Accepted: 12/12/2018] [Indexed: 02/07/2023]
Abstract
In the normal liver, cells interact closely through gap junctions. By providing a pathway for the trafficking of low molecular mass molecules, these channels contribute to tissue homeostasis and maintenance of hepatic function. Thus, dysfunction of gap junctions affects a wide variety of liver processes, such as differentiation, cell death, inflammation and fibrosis. In fact, dysfunctional gap junctions have been implicated, for more than a decade, in cholestatic disease, hepatic cancer and cirrhosis. Additionally, in recent years there is an increasing body of evidence that these channels are also involved in other relevant and prevalent liver pathological processes, such as non-alcoholic fatty liver disease, acute liver injury and portal hypertension. In parallel to these new clinical implications the available data include controversial observations. Thus, a comprehensive overview is required to better understand the functional complexity of these pores. This paper will review the most recent knowledge concerning gap junction dysfunction, with a special focus on the role of these channels in the pathogenesis of relevant clinical entities and on potential therapeutic targets that are amenable to modification by drugs.
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Affiliation(s)
| | | | - Rajiv Jalan
- UCL Institute for Liver and Digestive Health, Royal Free Medical School, London, UK
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22
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Novielli-Kuntz NM, Jelen M, Barr K, DeLalio LJ, Feng Q, Isakson BE, Gros R, Laird DW. Ablation of both Cx40 and Panx1 results in similar cardiovascular phenotypes exhibited in Cx40 knockout mice. Biosci Rep 2019; 39:BSR20182350. [PMID: 30745457 PMCID: PMC6393227 DOI: 10.1042/bsr20182350] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 01/10/2019] [Accepted: 02/05/2019] [Indexed: 11/30/2022] Open
Abstract
Connexins (Cxs) and pannexins (Panxs) are highly regulated large-pore channel-forming proteins that participate in cellular communication via small molecular exchange with the extracellular microenvironment, or in the case of connexins, directly between cells. Given the putative functional overlap between single membrane-spanning connexin hemichannels and Panx channels, and cardiovascular system prevalence, we generated the first Cx40-/-Panx1-/- mouse with the anticipation that this genetic modification would lead to a severe cardiovascular phenotype. Mice null for both Cx40 and Panx1 produced litter sizes and adult growth progression similar to wild-type (WT), Cx40-/- and Panx1-/- mice. Akin to Cx40-/- mice, Cx40-/-Panx1-/- mice exhibited cardiac hypertrophy and elevated systolic, diastolic, and mean arterial blood pressure compared with WT and Panx1-/- mice; however assessment of left ventricular ejection fraction and fractional shortening revealed no evidence of cardiac dysfunction between groups. Furthermore, Cx40-/-, Panx1-/-, and Cx40-/-Panx1-/- mice demonstrated impaired endothelial-mediated vasodilation of aortic segments to increasing concentrations of methacholine (MCh) compared with WT, highlighting roles for both Cx40 and Panx1 in vascular endothelial cell (EC) function. Surprisingly, elevated kidney renin mRNA expression, plasma renin activity, and extraglomerular renin-producing cell populations found in Cx40-/- mice was further exaggerated in double knockout mice. Thus, while gestation and gross development were conserved in Cx40-/-Panx1-/- mice, they exhibit cardiac hypertrophy, hypertension, and impaired endothelial-mediated vasodilation that phenocopies Cx40-/- mice. Nevertheless, the augmented renin homeostasis observed in the double knockout mice suggests that both Cx40 and Panx1 may play an integrative role.
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Affiliation(s)
| | - Meghan Jelen
- Department of Anatomy and Cell Biology, University of Western Ontario, London, Canada
| | - Kevin Barr
- Department of Anatomy and Cell Biology, University of Western Ontario, London, Canada
| | - Leon J DeLalio
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, U.S.A
| | - Qingping Feng
- Department of Physiology and Pharmacology London, ON, Canada
| | - Brant E Isakson
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, U.S.A
| | - Robert Gros
- Department of Physiology and Pharmacology London, ON, Canada
- Robarts Research Institute, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada
| | - Dale W Laird
- Department of Anatomy and Cell Biology, University of Western Ontario, London, Canada
- Department of Physiology and Pharmacology London, ON, Canada
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23
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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: 26] [Impact Index Per Article: 5.2] [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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24
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Khalyfa A, Gozal D. Connexins and Atrial Fibrillation in Obstructive Sleep Apnea. CURRENT SLEEP MEDICINE REPORTS 2018; 4:300-311. [PMID: 31106116 PMCID: PMC6516763 DOI: 10.1007/s40675-018-0130-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PURPOSE OF THE REVIEW To summarize the potential interactions between obstructive sleep apnea (OSA), atrial fibrillation (AF), and connexins. RECENT FINDINGS OSA is highly prevalent in patients with cardiovascular disease, and is associated with increased risk for end-organ substantial morbidities linked to autonomic nervous system imbalance, increased oxidative stress and inflammation, ultimately leading to reduced life expectancy. Epidemiological studies indicate that OSA is associated with increased incidence and progression of coronary heart disease, heart failure, stroke, as well as arrhythmias, particularly AF. Conversely, AF is very common among subjects referred for suspected OSA, and the prevalence of AF increases with OSA severity. The interrelationships between AF and OSA along with the well-known epidemiological links between these two conditions and obesity may reflect shared pathophysiological pathways, which may depend on the intercellular diffusion of signaling molecules into either the extracellular space or require cell-to-cell contact. Connexin signaling is accomplished via direct exchanges of cytosolic molecules between adjacent cells at gap membrane junctions for cell-to-cell coupling. The role of connexins in AF is now quite well established, but the impact of OSA on cardiac connexins has only recently begun to be investigated. Understanding the biology and regulatory mechanisms of connexins in OSA at the transcriptional, translational, and post-translational levels will undoubtedly require major efforts to decipher the breadth and complexity of connexin functions in OSA-induced AF. SUMMARY The risk of end-organ morbidities has initiated the search for circulating mechanistic biomarker signatures and the implementation of biomarker-based algorithms for precision-based diagnosis and risk assessment. Here we summarize recent findings in OSA as they relate to AF risk, and also review potential mechanisms linking OSA, AF and connexins.
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Affiliation(s)
- Abdelnaby Khalyfa
- Department of Pediatrics, Biological Sciences Division, Pritzker School of Medicine, The University of Chicago, Chicago IL 60637, USA
| | - David Gozal
- Department of Child Health, University of Missouri School of Medicine, Columbia, MO 65201, USA
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25
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Choi EJ, Yeo JH, Yoon SM, Lee J. Gambogic Acid and Its Analogs Inhibit Gap Junctional Intercellular Communication. Front Pharmacol 2018; 9:814. [PMID: 30104974 PMCID: PMC6077758 DOI: 10.3389/fphar.2018.00814] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 07/09/2018] [Indexed: 11/21/2022] Open
Abstract
Gap junctions (GJs) are intercellular channels composed of connexins. Cellular molecules smaller than 1 kDa can diffuse through GJs by a process termed gap junctional intercellular communication (GJIC), which plays essential roles in various pathological and physiological conditions. Gambogic acid (GA), a major component of a natural yellow dye, has been used as traditional medicine and has been reported to have various therapeutic effects, including an anti-cancer effect. In this study, two different GJ assay methods showed that GA and its analogs inhibited GJIC. The inhibition was rapidly reversible and was not mediated by changes in surface expression or S368 phosphorylation of Cx43, cellular calcium concentration, or redox state. We also developed an assay system to measure the intercellular communication induced by Cx40, Cx30, and Cx43. Dihydrogambogic acid (D-GA) potently inhibited GJIC by Cx40 (IC50 = 5.1 μM), whereas the IC50 value of carbenoxolone, which is known as a broad spectrum GJIC inhibitor, was 105.2 μM. Thus, D-GA can act as a pharmacological tool for the inhibition of Cx40.
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Affiliation(s)
- Eun J Choi
- College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, South Korea
| | - Joo H Yeo
- College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, South Korea
| | - Sei M Yoon
- College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, South Korea.,Department of Integrated OMICS for Biomedical Sciences, Yonsei University, Seoul, South Korea
| | - Jinu Lee
- College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, South Korea
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26
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Kolesová H, Bartoš M, Hsieh WC, Olejníčková V, Sedmera D. Novel approaches to study coronary vasculature development in mice. Dev Dyn 2018; 247:1018-1027. [DOI: 10.1002/dvdy.24637] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 05/04/2018] [Accepted: 05/08/2018] [Indexed: 12/19/2022] Open
Affiliation(s)
- Hana Kolesová
- Institute of Anatomy, First Faculty of Medicine; Charles University in Prague; Czech Republic
- Institute of Physiology; Czech Academy of Sciences; Prague Czech Republic
| | - Martin Bartoš
- Institute of Anatomy, First Faculty of Medicine; Charles University in Prague; Czech Republic
- Institute of Dental Medicine, First Faculty of Medicine; Charles University in Prague; Czech Republic
| | - Wan Chin Hsieh
- Institute of Anatomy, First Faculty of Medicine; Charles University in Prague; Czech Republic
| | - Veronika Olejníčková
- Institute of Anatomy, First Faculty of Medicine; Charles University in Prague; Czech Republic
- Institute of Physiology; Czech Academy of Sciences; Prague Czech Republic
| | - David Sedmera
- Institute of Anatomy, First Faculty of Medicine; Charles University in Prague; Czech Republic
- Institute of Physiology; Czech Academy of Sciences; Prague Czech Republic
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27
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Molica F, Figueroa XF, Kwak BR, Isakson BE, Gibbins JM. Connexins and Pannexins in Vascular Function and Disease. Int J Mol Sci 2018; 19:ijms19061663. [PMID: 29874791 PMCID: PMC6032213 DOI: 10.3390/ijms19061663] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 05/28/2018] [Accepted: 05/31/2018] [Indexed: 12/24/2022] Open
Abstract
Connexins (Cxs) and pannexins (Panxs) are ubiquitous membrane channel forming proteins that are critically involved in many aspects of vascular physiology and pathology. The permeation of ions and small metabolites through Panx channels, Cx hemichannels and gap junction channels confers a crucial role to these proteins in intercellular communication and in maintaining tissue homeostasis. This review provides an overview of current knowledge with respect to the pathophysiological role of these channels in large arteries, the microcirculation, veins, the lymphatic system and platelet function. The essential nature of these membrane proteins in vascular homeostasis is further emphasized by the pathologies that are linked to mutations and polymorphisms in Cx and Panx genes.
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Affiliation(s)
- Filippo Molica
- Department of Pathology and Immunology, University of Geneva, CH-1211 Geneva, Switzerland.
| | - Xavier F Figueroa
- Departamento de Fisiología, Faculdad de Ciencias Biológicas, Pontifica Universidad Católica de Chile, Santiago 8330025, Chile.
| | - Brenda R Kwak
- Department of Pathology and Immunology, University of Geneva, CH-1211 Geneva, Switzerland.
| | - Brant E Isakson
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.
| | - Jonathan M Gibbins
- Institute for Cardiovascular & Metabolic Research, School of Biological Sciences, Harborne Building, University of Reading, Reading RG6 6AS, UK.
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28
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Steppan D, Geis L, Pan L, Gross K, Wagner C, Kurtz A. Lack of connexin 40 decreases the calcium sensitivity of renin-secreting juxtaglomerular cells. Pflugers Arch 2018; 470:969-978. [PMID: 29427253 PMCID: PMC10751884 DOI: 10.1007/s00424-018-2119-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 01/24/2018] [Accepted: 02/02/2018] [Indexed: 11/29/2022]
Abstract
The so-called calcium paradoxon of renin describes the phenomenon that exocytosis of renin from juxtaglomerular cells of the kidney is stimulated by lowering of the extracellular calcium concentration. The yet poorly understood effect of extracellular calcium on renin secretion appears to depend on the function of the gap junction protein connexin 40 (Cx40) in renin-producing cells. This study aimed to elucidate the role of Cx40 for the calcium dependency of renin secretion in more detail by investigating if Cx40 function is really essential for the influence of extracellular calcium on renin secretion, if and how Cx40 affects intracellular calcium dynamics in renin-secreting cells and if Cx40-mediated gap junctional coupling of renin-secreting cells with the mesangial cell area is relevant for the influence of extracellular calcium on renin secretion. Renin secretion was studied in isolated perfused mouse kidneys. Calcium measurements were performed in renin-producing cells of microdissected glomeruli. The ultrastructure of renin-secreting cells was examined by electron microscopy. We found that Cx40 was not essential for stimulation of renin secretion by lowering of the extracellular calcium concentration. Instead, Cx40 increased the sensitivity of renin secretion response towards lowering of the extracellular calcium concentration. In line, the sensitivity and dynamics of intracellular calcium in response to lowering of extracellular calcium were dampened when renin-secreting cells lacked Cx40. Disruption of gap junctional coupling of renin-secreting cells by selective deletion of Cx40 from mesangial cells, however, did not change the stimulation of renin secretion by lowering of the extracellular calcium concentration. Deletion of Cx40 from renin cells but not from mesangial cells was associated with a shift of renin expression from perivascular cells of afferent arterioles to extraglomerular mesangial cells. Our findings suggest that Cx40 is not directly involved in the regulation of renin secretion by extracellular calcium. Instead, it appears that in renin-secreting cells of the kidney lacking Cx40, intracellular calcium dynamics and therefore also renin secretion are desensitized towards changes of extracellular calcium. Whether the dampened calcium response of renin-secreting cells lacking Cx40 function results from a direct involvement of Cx40 in intracellular calcium regulation or from the cell type shift of renin expression from perivascular to mesangial cells remains to be clarified. In any case, Cx40-mediated gap junctional coupling between renin and mesangial cells is not relevant for the calcium paradoxon of renin secretion.
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Affiliation(s)
- Dominik Steppan
- Institute of Physiology, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany.
| | - Lisa Geis
- Clinic for Nephrology, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
| | - Lin Pan
- Department of Pathology, Brigham and Women's Hospital, 652 NRB, 77 Ave Louis Pasteur, Boston, MA, 02115, USA
| | - Kenneth Gross
- Department of Molecular and Cellular Biology, Roswell Park Cancer Institute, Elm and Carlton Sts, Buffalo, NY, 14263-0001, USA
| | - Charlotte Wagner
- Institute of Physiology, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Armin Kurtz
- Institute of Physiology, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
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29
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Steppan D, Pan L, Gross KW, Kurtz A. Analysis of the calcium paradox of renin secretion. Am J Physiol Renal Physiol 2017; 315:F834-F843. [PMID: 29357428 DOI: 10.1152/ajprenal.00554.2017] [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: 12/23/2022] Open
Abstract
The secretion of the protease renin from renal juxtaglomerular cells is enhanced by subnormal extracellular calcium concentrations. The mechanisms underlying this atypical effect of calcium have not yet been unraveled. We therefore aimed to characterize the effect of extracellular calcium concentration on calcium handling of juxtaglomerular cells and on renin secretion in more detail. For this purpose, we used a combination of experiments with isolated perfused mouse kidneys and direct calcium measurements in renin-secreting cells in situ. We found that lowering of the extracellular calcium concentration led to a sustained elevation of renin secretion. Electron-microscopical analysis of renin-secreting cells exposed to subnormal extracellular calcium concentrations revealed big omega-shaped structures resulting from the intracellular fusion and subsequent emptying of renin storage vesicles. The calcium concentration dependencies as well as the kinetics of changes were rather similar for renin secretion and for renovascular resistance. Since vascular resistance is fundamentally influenced by myosin light chain kinase (MLCK), myosin light chain phosphatase (MLCP), and Rho-associated protein kinase (Rho-K) activities, we examined the effects of MLCK-, MLCP-, and Rho-K inhibitors on renin secretion. Only MLCK inhibition stimulated renin secretion. Conversely, inhibition of MCLP activity lowered perfusate flow and strongly inhibited renin secretion, which could not be reversed by lowering of the extracellular calcium concentration. Renin-secreting cells and smooth muscle cells of afferent arterioles showed immunoreactivity of MLCK. These findings suggest that the inhibitory effect of calcium on renin secretion could be explained by phosphorylation-dependent processes under control of the MLCK.
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Affiliation(s)
- D Steppan
- Institute of Physiology, University of Regensburg , Regensburg , Germany
| | - L Pan
- Department of Pathology, Brigham and Women's Hospital , Boston, Massachusetts
| | - K W Gross
- Department of Molecular and Cellular Biology, Roswell Park Cancer Institute , Buffalo, New York
| | - A Kurtz
- Institute of Physiology, University of Regensburg , Regensburg , Germany
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30
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Haefliger JA, Allagnat F, Hamard L, Le Gal L, Meda P, Nardelli-Haefliger D, Génot E, Alonso F. Targeting Cx40 (Connexin40) Expression or Function Reduces Angiogenesis in the Developing Mouse Retina. Arterioscler Thromb Vasc Biol 2017; 37:2136-2146. [PMID: 28982669 DOI: 10.1161/atvbaha.117.310072] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 09/20/2017] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Cx40 (Connexin40) forms intercellular channels that coordinate the electric conduction in the heart and the vasomotor tone in large vessels. The protein was shown to regulate tumoral angiogenesis; however, whether Cx40 also contributes to physiological angiogenesis is still unknown. APPROACH AND RESULTS Here, we show that Cx40 contributes to physiological angiogenesis. Genetic deletion of Cx40 leads to a reduction in vascular growth and capillary density in the neovascularization model of the mouse neonatal retina. At the angiogenic front, vessel sprouting is reduced, and the mural cells recruited along the sprouts display an altered phenotype. These alterations can be attributed to disturbed endothelial cell functions as selective reexpression of Cx40 in these cells restores normal angiogenesis. In vitro, targeting Cx40 in microvascular endothelial cells, by silencing its expression or by blocking gap junction channels, decreases their proliferation. Moreover, loss of Cx40 in these cells also increases their release of PDGF (platelet-derived growth factor) and promotes the chemoattraction of mural cells. In vivo, an intravitreal injection of a Cx40 inhibitory peptide, phenocopies the loss of Cx40 in the retinal vasculature of wild-type mice. CONCLUSIONS Collectively, our data show that endothelial Cx40 contributes to the early stages of physiological angiogenesis in the developing retina, by regulating vessel growth and maturation. Cx40 thus represents a novel therapeutic target for treating pathological ocular angiogenesis.
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Affiliation(s)
- Jacques-Antoine Haefliger
- From the Department of Medicine (J.-A.H., F.A., L.H., L.L.G., F.A.) and Department of Urology (D.N.H.), Lausanne University Hospital, Switzerland; Department of Cell Physiology and Metabolism, University of Geneva Medical Center, Switzerland (P.M.); and Centre de Recherche Cardio-Thoracique de Bordeaux (INSERM U1045), Université de Bordeaux, France (E.G., F.A.).
| | - Florent Allagnat
- From the Department of Medicine (J.-A.H., F.A., L.H., L.L.G., F.A.) and Department of Urology (D.N.H.), Lausanne University Hospital, Switzerland; Department of Cell Physiology and Metabolism, University of Geneva Medical Center, Switzerland (P.M.); and Centre de Recherche Cardio-Thoracique de Bordeaux (INSERM U1045), Université de Bordeaux, France (E.G., F.A.)
| | - Lauriane Hamard
- From the Department of Medicine (J.-A.H., F.A., L.H., L.L.G., F.A.) and Department of Urology (D.N.H.), Lausanne University Hospital, Switzerland; Department of Cell Physiology and Metabolism, University of Geneva Medical Center, Switzerland (P.M.); and Centre de Recherche Cardio-Thoracique de Bordeaux (INSERM U1045), Université de Bordeaux, France (E.G., F.A.)
| | - Loïc Le Gal
- From the Department of Medicine (J.-A.H., F.A., L.H., L.L.G., F.A.) and Department of Urology (D.N.H.), Lausanne University Hospital, Switzerland; Department of Cell Physiology and Metabolism, University of Geneva Medical Center, Switzerland (P.M.); and Centre de Recherche Cardio-Thoracique de Bordeaux (INSERM U1045), Université de Bordeaux, France (E.G., F.A.)
| | - Paolo Meda
- From the Department of Medicine (J.-A.H., F.A., L.H., L.L.G., F.A.) and Department of Urology (D.N.H.), Lausanne University Hospital, Switzerland; Department of Cell Physiology and Metabolism, University of Geneva Medical Center, Switzerland (P.M.); and Centre de Recherche Cardio-Thoracique de Bordeaux (INSERM U1045), Université de Bordeaux, France (E.G., F.A.)
| | - Denise Nardelli-Haefliger
- From the Department of Medicine (J.-A.H., F.A., L.H., L.L.G., F.A.) and Department of Urology (D.N.H.), Lausanne University Hospital, Switzerland; Department of Cell Physiology and Metabolism, University of Geneva Medical Center, Switzerland (P.M.); and Centre de Recherche Cardio-Thoracique de Bordeaux (INSERM U1045), Université de Bordeaux, France (E.G., F.A.)
| | - Elisabeth Génot
- From the Department of Medicine (J.-A.H., F.A., L.H., L.L.G., F.A.) and Department of Urology (D.N.H.), Lausanne University Hospital, Switzerland; Department of Cell Physiology and Metabolism, University of Geneva Medical Center, Switzerland (P.M.); and Centre de Recherche Cardio-Thoracique de Bordeaux (INSERM U1045), Université de Bordeaux, France (E.G., F.A.)
| | - Florian Alonso
- From the Department of Medicine (J.-A.H., F.A., L.H., L.L.G., F.A.) and Department of Urology (D.N.H.), Lausanne University Hospital, Switzerland; Department of Cell Physiology and Metabolism, University of Geneva Medical Center, Switzerland (P.M.); and Centre de Recherche Cardio-Thoracique de Bordeaux (INSERM U1045), Université de Bordeaux, France (E.G., F.A.).
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31
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The Role of Gap Junction-Mediated Endothelial Cell-Cell Interaction in the Crosstalk between Inflammation and Blood Coagulation. Int J Mol Sci 2017; 18:ijms18112254. [PMID: 29077057 PMCID: PMC5713224 DOI: 10.3390/ijms18112254] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 10/21/2017] [Accepted: 10/24/2017] [Indexed: 12/29/2022] Open
Abstract
Endothelial cells (ECs) play a pivotal role in the crosstalk between blood coagulation and inflammation. Endothelial cellular dysfunction underlies the development of vascular inflammatory diseases. Recent studies have revealed that aberrant gap junctions (GJs) and connexin (Cx) hemichannels participate in the progression of cardiovascular diseases such as cardiac infarction, hypertension and atherosclerosis. ECs can communicate with adjacent ECs, vascular smooth muscle cells, leukocytes and platelets via GJs and Cx channels. ECs dynamically regulate the expression of numerous Cxs, as well as GJ functionality, in the context of inflammation. Alterations to either result in various side effects across a wide range of vascular functions. Here, we review the roles of endothelial GJs and Cx channels in vascular inflammation, blood coagulation and leukocyte adhesion. In addition, we discuss the relevant molecular mechanisms that endothelial GJs and Cx channels regulate, both the endothelial functions and mechanical properties of ECs. A better understanding of these processes promises the possibility of pharmacological treatments for vascular pathogenesis.
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Welsh DG, Tran CHT, Hald BO, Sancho M. The Conducted Vasomotor Response: Function, Biophysical Basis, and Pharmacological Control. Annu Rev Pharmacol Toxicol 2017; 58:391-410. [PMID: 28968190 DOI: 10.1146/annurev-pharmtox-010617-052623] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Arterial tone is coordinated among vessel segments to optimize nutrient transport and organ function. Coordinated vasomotor activity is remarkable to observe and depends on stimuli, sparsely generated in tissue, eliciting electrical responses that conduct lengthwise among electrically coupled vascular cells. The conducted response is the focus of this topical review, and in this regard, the authors highlight literature that advances an appreciation of functional significance, cellular mechanisms, and biophysical principles. Of particular note, this review stresses that conduction is enabled by a defined pattern of charge movement along the arterial wall as set by three key parameters (tissue structure, gap junctional resistivity, and ion channel activity). The impact of disease on conduction is carefully discussed, as are potential strategies to restore this key biological response and, along with it, the match of blood flow delivery with tissue energetic demand.
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Affiliation(s)
- Donald G Welsh
- Robarts Research Institute, Department of Physiology and Pharmacology, Schulich School of Medicine, University of Western Ontario, London, Ontario N6A 5B7, Canada;
| | - Cam Ha T Tran
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Bjorn O Hald
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen DK-2200, Denmark
| | - Maria Sancho
- Robarts Research Institute, Department of Physiology and Pharmacology, Schulich School of Medicine, University of Western Ontario, London, Ontario N6A 5B7, Canada;
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Komarova YA, Kruse K, Mehta D, Malik AB. Protein Interactions at Endothelial Junctions and Signaling Mechanisms Regulating Endothelial Permeability. Circ Res 2017; 120:179-206. [PMID: 28057793 DOI: 10.1161/circresaha.116.306534] [Citation(s) in RCA: 300] [Impact Index Per Article: 42.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 10/04/2016] [Accepted: 10/06/2016] [Indexed: 12/31/2022]
Abstract
The monolayer of endothelial cells lining the vessel wall forms a semipermeable barrier (in all tissue except the relatively impermeable blood-brain and inner retinal barriers) that regulates tissue-fluid homeostasis, transport of nutrients, and migration of blood cells across the barrier. Permeability of the endothelial barrier is primarily regulated by a protein complex called adherens junctions. Adherens junctions are not static structures; they are continuously remodeled in response to mechanical and chemical cues in both physiological and pathological settings. Here, we discuss recent insights into the post-translational modifications of junctional proteins and signaling pathways regulating plasticity of adherens junctions and endothelial permeability. We also discuss in the context of what is already known and newly defined signaling pathways that mediate endothelial barrier leakiness (hyperpermeability) that are important in the pathogenesis of cardiovascular and lung diseases and vascular inflammation.
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Affiliation(s)
- Yulia A Komarova
- From the Department of Pharmacology and the Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago
| | - Kevin Kruse
- From the Department of Pharmacology and the Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago
| | - Dolly Mehta
- From the Department of Pharmacology and the Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago
| | - Asrar B Malik
- From the Department of Pharmacology and the Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago.
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Nakase T, Ishikawa T, Miyata H. Protective effects of connexins in atheromatous plaques in patients of carotid artery stenosis. Neuropathology 2017; 37:97-104. [PMID: 27739121 DOI: 10.1111/neup.12345] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 09/02/2016] [Accepted: 09/02/2016] [Indexed: 11/26/2022]
Abstract
Fragility of atheromatous plaque in the internal carotid artery can be a risk of brain infarction. The activation of macrophages by oxidative stress and the vulnerability of vascular endothelial cells have been reported to participate in the fragility of atheromatous plaque. Therefore, from the view point of prevention of brain infarction, we investigated the pathological factors which may influence the stabilization of atheromatous plaque. Patients undertaking carotid endoarterectomy (CEA) were continuously screened. Then, 21 samples were obtained from the atheromatous plaques of CEA patients. The expression of connexin (Cx) which composes a gap junction, an intercellular communication organ, was immunohistochemicaly observed. The expression of CD36, an oxidized low-density lipoprotein receptor, was assessed as a marker of oxidative stress. As a result, asymptomatic plaques which were assumed the stable plaques expressed Cx43 along with CD36 expression. In contrast, in the symptomatic plaques, the expression of Cx43 was few and there was almost no coexpression with CD36. The distribution of Cx37 expression was not different between asymptomatic and symptomatic plaques. The expressions of CD36, Cx37 and Cx43 showed no relation to the previous treatment with statins. In conclusion, Cx43 might contribute to the stabilization of atheromatous plaque which is affected by oxidative stress.
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Affiliation(s)
- Taizen Nakase
- Department of Stroke Science, Research Institute for Brain and Blood Vessels - Akita, Japan
| | - Tatsuya Ishikawa
- Department of Surgical Neurology, Research Institute for Brain and Blood Vessels - Akita, Japan
| | - Hajime Miyata
- Department of Neuropathology, Research Institute for Brain and Blood Vessels - Akita, Japan
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Meda P. Gap junction proteins are key drivers of endocrine function. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1860:124-140. [PMID: 28284720 DOI: 10.1016/j.bbamem.2017.03.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 03/03/2017] [Accepted: 03/06/2017] [Indexed: 01/07/2023]
Abstract
It has long been known that the main secretory cells of exocrine and endocrine glands are connected by gap junctions, made by a variety of connexin species that ensure their electrical and metabolic coupling. Experiments in culture systems and animal models have since provided increasing evidence that connexin signaling contributes to control the biosynthesis and release of secretory products, as well as to the life and death of secretory cells. More recently, genetic studies have further provided the first lines of evidence that connexins also control the function of human glands, which are central to the pathogenesis of major endocrine diseases. Here, we summarize the recent information gathered on connexin signaling in these systems, since the last reviews on the topic, with particular regard to the pancreatic beta cells which produce insulin, and the renal cells which produce renin. These cells are keys to the development of various forms of diabetes and hypertension, respectively, and combine to account for the exploding, worldwide prevalence of the metabolic syndrome. This article is part of a Special Issue entitled: Gap Junction Proteins edited by Jean Claude Herve.
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Affiliation(s)
- Paolo Meda
- Department of Cell Physiology and Metabolism, University of Geneva Medical School, Switzerland.
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36
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Thuesen AD, Lyngsø KS, Rasmussen L, Stubbe J, Skøtt O, Poulsen FR, Pedersen CB, Rasmussen LM, Hansen PBL. P/Q-type and T-type voltage-gated calcium channels are involved in the contraction of mammary and brain blood vessels from hypertensive patients. Acta Physiol (Oxf) 2017; 219:640-651. [PMID: 27273014 DOI: 10.1111/apha.12732] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 03/21/2016] [Accepted: 06/01/2016] [Indexed: 12/12/2022]
Abstract
AIM Calcium channel blockers are widely used in cardiovascular diseases. Besides L-type channels, T- and P/Q-type calcium channels are involved in the contraction of human renal blood vessels. It was hypothesized that T- and P/Q-type channels are involved in the contraction of human brain and mammary blood vessels. METHODS Internal mammary arteries from bypass surgery patients and cerebral arterioles from patients with brain tumours with and without hypertension were tested in a myograph and perfusion set-up. PCR and immunohistochemistry were performed on isolated blood vessels. RESULTS The P/Q-type antagonist ω-agatoxin IVA (10-8 mol L-1 ) and the T-type calcium blocker mibefradil (10-7 mol L-1 ) inhibited KCl depolarization-induced contraction in mammary arteries from hypertensive patients with no effect on blood vessels from normotensive patients. ω-Agatoxin IVA decreased contraction in cerebral arterioles from hypertensive patients. L-type blocker nifedipine abolished the contraction in mammary arteries. PCR analysis showed expression of P/Q-type (Cav 2.1), T-type (Cav 3.1 and Cav 3.2) and L-type (Cav 1.2) calcium channels in mammary and cerebral arteries. Immunohistochemical labelling of mammary and cerebral arteries revealed the presence of Cav 2.1 in endothelial and smooth muscle cells. Cav 3.1 was also detected in mammary arteries. CONCLUSION P/Q- and T-type Cav are present in human internal mammary arteries and in cerebral penetrating arterioles. P/Q- and T-type calcium channels are involved in the contraction of mammary arteries from hypertensive patients but not from normotensive patients. Furthermore, in cerebral arterioles P/Q-type channels importance was restricted to hypertensive patients might lead to that T- and P/Q-type channels could be a new target in hypertensive patients.
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Affiliation(s)
- A. D. Thuesen
- Department of Cardiovascular and Renal Research; Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
| | - K. S. Lyngsø
- Department of Cardiovascular and Renal Research; Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
| | - L. Rasmussen
- Department of Cardiovascular and Renal Research; Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
| | - J. Stubbe
- Department of Cardiovascular and Renal Research; Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
| | - O. Skøtt
- Department of Cardiovascular and Renal Research; Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
| | - F. R. Poulsen
- Department of Neurosurgery; Odense University Hospital; Odense Denmark
- Clinical Institute; University of Southern Denmark; Odense Denmark
| | - C. B. Pedersen
- Department of Neurosurgery; Odense University Hospital; Odense Denmark
| | - L. M. Rasmussen
- Clinical Institute; University of Southern Denmark; Odense Denmark
- Department of Clinical Biochemistry and Pharmacology; Centre for Individualized Medicine in Arterial Diseases; Odense University Hospital; Odense Denmark
| | - P. B. L. Hansen
- Department of Cardiovascular and Renal Research; Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
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Abstract
The mouse isolated perfused kidney (MIPK) is a technique for keeping a mouse kidney under ex vivo conditions perfused and functional for 1 hr. This is a prerequisite for studying the physiology of the isolated organ and for many innovative applications that may be possible in the future, including perfusion decellularization for kidney bioengineering or the administration of anti-rejection or genome-editing drugs in high doses to prime the kidney for transplantation. During the time of the perfusion, the kidney can be manipulated, renal function can be assessed, and various pharmaceuticals administered. After the procedure, the kidney can be transplanted or processed for molecular biology, biochemical analysis, or microscopy. This paper describes the perfusate and the surgical technique needed for the ex vivo perfusion of mouse kidneys. Details of the perfusion apparatus are given and data are presented showing the viability of the kidney's preparation: renal blood flow, vascular resistance, and urine data as functional, transmission electron micrographs of different nephron segments as morphological readouts, and western blots of transport proteins of different nephron segments as molecular readout.
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Affiliation(s)
- Jan Czogalla
- Institute of Anatomy, Swiss National Centre of Competence in Research Kidney, University of Zürich;
| | | | - Johannes Loffing
- Institute of Anatomy, Swiss National Centre of Competence in Research Kidney, University of Zürich
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38
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Scallan JP, Zawieja SD, Castorena-Gonzalez JA, Davis MJ. Lymphatic pumping: mechanics, mechanisms and malfunction. J Physiol 2016; 594:5749-5768. [PMID: 27219461 PMCID: PMC5063934 DOI: 10.1113/jp272088] [Citation(s) in RCA: 229] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 05/17/2016] [Indexed: 12/19/2022] Open
Abstract
A combination of extrinsic (passive) and intrinsic (active) forces move lymph against a hydrostatic pressure gradient in most regions of the body. The effectiveness of the lymph pump system impacts not only interstitial fluid balance but other aspects of overall homeostasis. This review focuses on the mechanisms that regulate the intrinsic, active contractions of collecting lymphatic vessels in relation to their ability to actively transport lymph. Lymph propulsion requires not only robust contractions of lymphatic muscle cells, but contraction waves that are synchronized over the length of a lymphangion as well as properly functioning intraluminal valves. Normal lymphatic pump function is determined by the intrinsic properties of lymphatic muscle and the regulation of pumping by lymphatic preload, afterload, spontaneous contraction rate, contractility and neural influences. Lymphatic contractile dysfunction, barrier dysfunction and valve defects are common themes among pathologies that directly involve the lymphatic system, such as inherited and acquired forms of lymphoedema, and pathologies that indirectly involve the lymphatic system, such as inflammation, obesity and metabolic syndrome, and inflammatory bowel disease.
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Affiliation(s)
- Joshua P Scallan
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, USA
| | - Scott D Zawieja
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, USA
| | | | - Michael J Davis
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, USA.
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Willebrords J, Crespo Yanguas S, Maes M, Decrock E, Wang N, Leybaert L, Kwak BR, Green CR, Cogliati B, Vinken M. Connexins and their channels in inflammation. Crit Rev Biochem Mol Biol 2016; 51:413-439. [PMID: 27387655 PMCID: PMC5584657 DOI: 10.1080/10409238.2016.1204980] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Inflammation may be caused by a variety of factors and is a hallmark of a plethora of acute and chronic diseases. The purpose of inflammation is to eliminate the initial cell injury trigger, to clear out dead cells from damaged tissue and to initiate tissue regeneration. Despite the wealth of knowledge regarding the involvement of cellular communication in inflammation, studies on the role of connexin-based channels in this process have only begun to emerge in the last few years. In this paper, a state-of-the-art overview of the effects of inflammation on connexin signaling is provided. Vice versa, the involvement of connexins and their channels in inflammation will be discussed by relying on studies that use a variety of experimental tools, such as genetically modified animals, small interfering RNA and connexin-based channel blockers. A better understanding of the importance of connexin signaling in inflammation may open up towards clinical perspectives.
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Affiliation(s)
- Joost Willebrords
- Department of In Vitro Toxicology and
Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels,
Belgium; Joost Willebrords: + Tel: 32 2 477 45 87, Michaël Maes: Tel: +32 2
477 45 87, Sara Crespo Yanguas: Tel: +32 2 477 45 87
| | - Sara Crespo Yanguas
- Department of In Vitro Toxicology and
Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels,
Belgium; Joost Willebrords: + Tel: 32 2 477 45 87, Michaël Maes: Tel: +32 2
477 45 87, Sara Crespo Yanguas: Tel: +32 2 477 45 87
| | - Michaël Maes
- Department of In Vitro Toxicology and
Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels,
Belgium; Joost Willebrords: + Tel: 32 2 477 45 87, Michaël Maes: Tel: +32 2
477 45 87, Sara Crespo Yanguas: Tel: +32 2 477 45 87
| | - Elke Decrock
- Department of Basic Medical Sciences, Physiology Group, Ghent
University, De Pintelaan 185, 9000 Ghent, Belgium; Elke Decrock: Tel: +32 9 332 39
73, Nan Wang: Tel: +32 9 332 39 38, Luc Leybaert: Tel: +32 9 332 33 66
| | - Nan Wang
- Department of Basic Medical Sciences, Physiology Group, Ghent
University, De Pintelaan 185, 9000 Ghent, Belgium; Elke Decrock: Tel: +32 9 332 39
73, Nan Wang: Tel: +32 9 332 39 38, Luc Leybaert: Tel: +32 9 332 33 66
| | - Luc Leybaert
- Department of Basic Medical Sciences, Physiology Group, Ghent
University, De Pintelaan 185, 9000 Ghent, Belgium; Elke Decrock: Tel: +32 9 332 39
73, Nan Wang: Tel: +32 9 332 39 38, Luc Leybaert: Tel: +32 9 332 33 66
| | - Brenda R. Kwak
- Department of Pathology and Immunology and Division of Cardiology,
University of Geneva, Rue Michel-Servet 1, CH-1211 Geneva, Switzerland; Brenda R.
Kwak: Tel: +41 22 379 57 37
| | - Colin R. Green
- Department of Ophthalmology and New Zealand National Eye Centre,
University of Auckland, New Zealand; Colin R. Green: Tel: +64 9 923 61 35
| | - Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal
Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87,
05508-270 São Paulo, Brazil; Bruno Cogliati: Tel: +55 11 30 91 12 00
| | - Mathieu Vinken
- Department of In Vitro Toxicology and
Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels,
Belgium; Joost Willebrords: + Tel: 32 2 477 45 87, Michaël Maes: Tel: +32 2
477 45 87, Sara Crespo Yanguas: Tel: +32 2 477 45 87
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40
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Siragusa M, Fleming I. The eNOS signalosome and its link to endothelial dysfunction. Pflugers Arch 2016; 468:1125-1137. [DOI: 10.1007/s00424-016-1839-0] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Accepted: 05/10/2016] [Indexed: 12/17/2022]
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41
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Schmidt K, Windler R, de Wit C. Communication Through Gap Junctions in the Endothelium. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2016; 77:209-40. [PMID: 27451099 DOI: 10.1016/bs.apha.2016.04.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A swarm of fish displays a collective behavior (swarm behavior) and moves "en masse" despite the huge number of individual animals. In analogy, organ function is supported by a huge number of cells that act in an orchestrated fashion and this applies also to vascular cells along the vessel length. It is obvious that communication is required to achieve this vital goal. Gap junctions with their modular bricks, connexins (Cxs), provide channels that interlink the cytosol of adjacent cells by a pore sealed against the extracellular space. This allows the transfer of ions and charge and thereby the travel of membrane potential changes along the vascular wall. The endothelium provides a low-resistance pathway that depends crucially on connexin40 which is required for long-distance conduction of dilator signals in the microcirculation. The experimental evidence for membrane potential changes synchronizing vascular behavior is manifold but the functional verification of a physiologic role is still open. Other molecules may also be exchanged that possibly contribute to the synchronization (eg, Ca(2+)). Recent data suggest that vascular Cxs have more functions than just facilitating communication. As pharmacological tools to modulate gap junctions are lacking, Cx-deficient mice provide currently the standard to unravel their vascular functions. These include arteriolar dilation during functional hyperemia, hypoxic pulmonary vasoconstriction, vascular collateralization after ischemia, and feedback inhibition on renin secretion in the kidney.
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Affiliation(s)
- K Schmidt
- Institut für Physiologie, Universität zu Lübeck, Lübeck, Germany; Deutsches Zentrum für Herz-Kreislauf-Forschung (DZHK) e.V. (German Center for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Lübeck, Germany
| | - R Windler
- Institut für Physiologie, Universität zu Lübeck, Lübeck, Germany; Deutsches Zentrum für Herz-Kreislauf-Forschung (DZHK) e.V. (German Center for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Lübeck, Germany
| | - C de Wit
- Institut für Physiologie, Universität zu Lübeck, Lübeck, Germany; Deutsches Zentrum für Herz-Kreislauf-Forschung (DZHK) e.V. (German Center for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Lübeck, Germany.
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43
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Nitric Oxide Deficit Drives Intimal Hyperplasia in Mouse Models of Hypertension. Eur J Vasc Endovasc Surg 2016; 51:733-42. [DOI: 10.1016/j.ejvs.2016.01.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 01/29/2016] [Indexed: 01/26/2023]
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44
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Alonso F, Domingos-Pereira S, Le Gal L, Derré L, Meda P, Jichlinski P, Nardelli-Haefliger D, Haefliger JA. Targeting endothelial connexin40 inhibits tumor growth by reducing angiogenesis and improving vessel perfusion. Oncotarget 2016; 7:14015-28. [PMID: 26883111 PMCID: PMC4924695 DOI: 10.18632/oncotarget.7370] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 01/29/2016] [Indexed: 01/09/2023] Open
Abstract
Endothelial connexin40 (Cx40) contributes to regulate the structure and function of vessels. We have examined whether the protein also modulates the altered growth of vessels in tumor models established in control mice (WT), mice lacking Cx40 (Cx40-/-), and mice expressing the protein solely in endothelial cells (Tie2-Cx40). Tumoral angiogenesis and growth were reduced, whereas vessel perfusion, smooth muscle cell (SMC) coverage and animal survival were increased in Cx40-/- but not Tie2-Cx40 mice, revealing a critical involvement of endothelial Cx40 in transformed tissues independently of the hypertensive status of Cx40-/- mice. As a result, Cx40-/- mice bearing tumors survived significantly longer than corresponding controls, including after a cytotoxic administration. Comparable observations were made in WT mice injected with a peptide targeting Cx40, supporting the Cx40 involvement. This involvement was further confirmed in the absence of Cx40 or by peptide-inhibition of this connexin in aorta-sprouting, matrigel plug and SMC migration assays, and associated with a decreased expression of the phosphorylated form of endothelial nitric oxide synthase. The data identify Cx40 as a potential novel target in cancer treatment.
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MESH Headings
- Animals
- Aorta/pathology
- Apoptosis
- Biomarkers, Tumor/metabolism
- Blood Vessels/physiology
- Cell Proliferation
- Connexins/antagonists & inhibitors
- Connexins/metabolism
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/pathology
- Female
- Humans
- Lung Neoplasms/blood supply
- Lung Neoplasms/pathology
- Lung Neoplasms/prevention & control
- Melanoma, Experimental/blood supply
- Melanoma, Experimental/pathology
- Melanoma, Experimental/prevention & control
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Neoplasm Invasiveness
- Neovascularization, Pathologic/prevention & control
- Perfusion
- Tumor Cells, Cultured
- Urinary Bladder Neoplasms/blood supply
- Urinary Bladder Neoplasms/pathology
- Urinary Bladder Neoplasms/prevention & control
- Gap Junction alpha-5 Protein
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Affiliation(s)
- Florian Alonso
- Department of Medicine, Lausanne University Hospital, Lausanne, Switzerland
| | | | - Loïc Le Gal
- Department of Medicine, Lausanne University Hospital, Lausanne, Switzerland
| | - Laurent Derré
- Department of Urology, Lausanne University Hospital, Lausanne, Switzerland
| | - Paolo Meda
- Department of Cell Physiology and Metabolism, University of Geneva, Medical Center, Geneva, Switzerland
| | - Patrice Jichlinski
- Department of Urology, Lausanne University Hospital, Lausanne, Switzerland
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45
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Guan Z, Fellner RC, Van Beusecum J, Inscho EW. P2 receptors in renal autoregulation. Curr Vasc Pharmacol 2015; 12:818-28. [PMID: 24066935 DOI: 10.2174/15701611113116660152] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 03/06/2013] [Accepted: 05/01/2014] [Indexed: 11/22/2022]
Abstract
Autoregulation of renal blood flow and glomerular filtration rate is an essential function of the renal microcirculation. While the existence of this phenomenon has been known for many years, the exact mechanisms that underlie this regulatory system remain poorly understood. The work of many investigators has provided insights into many aspects of the autoregulatory mechanism, but many critical components remain elusive. This review is intended to update the reader on the role of P2 purinoceptors as a postulated mechanism responsible for renal autoregulatory resistance adjustments. It will summarize recent advances in normal function and it will touch on more recent ideas regarding autoregulatory insufficiency in hypertension and inflammation. Current thoughts on the nature of the mechanosensor responsible for myogenic behavior will be also be discussed as well as current thoughts on the mechanisms involved in ATP release to the extracellular fluid space.
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Affiliation(s)
| | | | | | - Edward W Inscho
- Department of Physiology, Medical College of Georgia, Georgia Regents University, 1120 15th Street, Augusta, Georgia 30912-3000.
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46
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Abed AB, Kavvadas P, Chadjichristos CE. Functional roles of connexins and pannexins in the kidney. Cell Mol Life Sci 2015; 72:2869-77. [PMID: 26082183 PMCID: PMC11113829 DOI: 10.1007/s00018-015-1964-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [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: 12/22/2022]
Abstract
Kidneys are highly complex organs, playing a crucial role in human physiopathology, as they are implicated in vital processes, such as fluid filtration and vasomotor tone regulation. There is growing evidence that gap junctions are major determinants of renal physiopathology. It has been demonstrated that their expression or channel activity may vary depending on physiological and pathological situations within distinct renal compartments. While some studies have focused on the role of connexins in renal physiology, our knowledge regarding the functional relevance of pannexins is still very limited. In this paper, we provide an overview of the involvement of connexins, pannexins and their channels in various physiological processes related to different renal compartments.
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Affiliation(s)
- Ahmed B. Abed
- INSERM UMR-S1155, Batiment Recherche, Tenon Hospital, 4 rue de la Chine, 75020 Paris, France
- Sorbonne Universite´s, UPMC Univ Paris 6, Paris, France
| | - Panagiotis Kavvadas
- INSERM UMR-S1155, Batiment Recherche, Tenon Hospital, 4 rue de la Chine, 75020 Paris, France
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Machura K, Neubauer B, Müller H, Tauber P, Kurtz A, Kurtz L. Connexin 40 is dispensable for vascular renin cell recruitment but is indispensable for vascular baroreceptor control of renin secretion. Pflugers Arch 2015; 467:1825-34. [PMID: 25241776 DOI: 10.1007/s00424-014-1615-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 09/11/2014] [Accepted: 09/12/2014] [Indexed: 10/24/2022]
Abstract
Defects of the gap junction protein connexin 40 (Cx40) in renin-secreting cells (RSCs) of the kidney lead to a shift of the localization of RSCs from the media layer of afferent arterioles to the periglomerular interstitium. The dislocation of RSCs goes in parallel with elevated plasma renin levels, impaired pressure control of renin secretion, and hypertension. The reasons for the extravascular shift of RSCs and the blunted pressure regulation of renin secretion caused by the absence of Cx40 are still unclear. We have therefore addressed the question if Cx40 is essential for the metaplastic transformation of preglomerular vascular smooth muscle cells (SMCs) into RSCs and if Cx40 is essential for the pressure control of renin secretion from RSCs located in the media layer of afferent arterioles. For our study, we used mice lacking the angiotensin II type 1A (AT1A) receptors, which display a prominent and reversible salt-sensitive metaplastic transformation of SMCs into RSCs. This mouse line was crossed with Cx40-deficient mice to obtain AT1A and Cx40 double deleted mice. The kidneys of AT1A (-/-)Cx40(-/-) mice kept on normal salt (0.3 %) displayed RSCs both in the inner media layer of preglomerular vessels and in the periglomerular interstitium. In contrast to hypotensive AT1A (-/-) (mean bp syst 112 mmHg) and hypertensive Cx40(-/-) (mean bp syst 160 mmHg) mice AT1A (-/-)Cx40(-/-) mice were normotensive(mean bp syst 130 mmHg). Pressure regulation of renin secretion from isolated kidneys was normal in AT1A (-/-) mice, but was absent in AT1A (-/-)Cx40(-/-) mice alike in Cx40(-/-) mice. Low-salt diet (0.02 %) increased RSC numbers in the media layer, whilst high-salt diet (4 %) caused disappearance of RSCs in the media layer but not in the periglomerular interstitium. Blood pressure was clearly salt sensitive both in AT1A (-/-) and in AT1A (-/-)Cx40(-/-) mice but was shifted to higher pressure values in the latter genotype. Our data indicate that Cx40 is not a requirement for intramural vascular localization of RSCs nor for reversible metaplastic transformation of SMCs into RSCs. Therefore, the ectopic localization of RSCs in Cx40(-/-) kidneys is more likely due to a disturbed intercellular communication rather than being the result of chronic overactivation of the renin-angiotensin-aldosterone system or hypertension. Moreover, our findings suggest that Cx40 is a requirement for the pressure control of renin secretion irrespective of the localization of RSCs.
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MESH Headings
- Animals
- Baroreflex
- Blood Pressure
- Cell Movement
- Connexins/deficiency
- Connexins/genetics
- Connexins/metabolism
- Diet, Sodium-Restricted
- Female
- Genotype
- Hypertension/genetics
- Hypertension/metabolism
- Hypertension/physiopathology
- Hypotension/genetics
- Hypotension/metabolism
- Hypotension/physiopathology
- Kidney/blood supply
- Kidney/metabolism
- Mechanotransduction, Cellular
- Mice, 129 Strain
- Mice, Inbred C57BL
- Mice, Knockout
- Muscle, Smooth, Vascular/metabolism
- Myocytes, Smooth Muscle/metabolism
- Phenotype
- Pressoreceptors/metabolism
- RNA, Messenger/metabolism
- Receptor, Angiotensin, Type 1/genetics
- Receptor, Angiotensin, Type 1/metabolism
- Renin/genetics
- Renin/metabolism
- Renin-Angiotensin System
- Sodium Chloride, Dietary
- Gap Junction alpha-5 Protein
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Affiliation(s)
- Katharina Machura
- Institut für Physiologie, Universität Regensburg, 93053, Regensburg, Germany,
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Jacobsen JCB, Sorensen CM. Influence of Connexin40 on the renal myogenic response in murine afferent arterioles. Physiol Rep 2015; 3:3/5/e12416. [PMID: 26009638 PMCID: PMC4463840 DOI: 10.14814/phy2.12416] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Renal autoregulation consists of two main mechanisms; the myogenic response and the tubuloglomerular feedback mechanism (TGF). Increases in renal perfusion pressure activate both mechanisms causing a reduction in diameter of the afferent arteriole (AA) resulting in stabilization of the glomerular pressure. It has previously been shown that connexin-40 (Cx40) is essential in the renal autoregulation and mediates the TGF mechanism. The aim of this study was to characterize the myogenic properties of the AA in wild-type and connexin-40 knockout (Cx40KO) mice using both in situ diameter measurements and modeling. We hypothesized that absence of Cx40 would not per se affect myogenic properties as Cx40 is expressed primarily in the endothelium and as the myogenic response is known to be present also in isolated, endothelium-denuded vessels. Methods used were the isolated perfused juxtamedullary nephron preparation to allow diameter measurements of the AA. A simple mathematical model of the myogenic response based on experimental parameters was implemented. Our findings show that the myogenic response is completely preserved in the AA of the Cx40KO and if anything, the stress sensitivity of the smooth muscle cell in the vascular wall is increased rather than reduced as compared to the WT. These findings are compatible with the view of the myogenic response being primarily a local response to the local transmural pressure.
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Affiliation(s)
- Jens Christian B Jacobsen
- Department of Biomedical Sciences, Division of Renal and Vascular Physiology, University of Copenhagen, Copenhagen, Denmark
| | - Charlotte M Sorensen
- Department of Biomedical Sciences, Division of Renal and Vascular Physiology, University of Copenhagen, Copenhagen, Denmark
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Schmidt K, Kaiser FJ, Erdmann J, Wit CD. Two polymorphisms in the Cx40 promoter are associated with hypertension and left ventricular hypertrophy preferentially in men. Clin Exp Hypertens 2015; 37:580-6. [PMID: 25992486 DOI: 10.3109/10641963.2015.1026043] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 02/17/2015] [Accepted: 02/18/2015] [Indexed: 11/13/2022]
Abstract
BACKGROUND Lack of connexin40, a gap junction protein expressed in endothelial and renin-producing cells, results in hypertension and cardiac hypertrophy in mice due to unleashed renin production caused by disruption of the pressure-induced feedback inhibition. We analysed human GJA5 consisting of two exons (exon1A or 1B and exon2) in a selected cohort identified by a single nucleotide polymorphism (SNP) in the GJA5 intron for polymorphisms and putative association with hypertension and left ventricular hypertrophy (LVH). METHODS Individuals carrying a SNP in the intron of GJA5 (rs791295) were selected from the MONICA/KORA cohort (n = 1677) and searched for GJA5 polymorphisms. We accessed DNA of 178 probands, of which 26 suffered from LVH, 112 were hypertensive and 29 normotensive (unknown: 11). RESULTS Sequencing of the GJA5 coding region did not reveal alterations suggesting the expression of functional connexin40 in all probands. Sequencing of the upstream region of transcript 1A including exon1A revealed two previously described linked SNPs (rs35594137 -44G>A; rs11552588 + 71A>G) at an increased frequency. Moreover, the rare genotype was significantly associated with hypertension and LVH with a preponderance in men. Functional analysis in a reporter gene assay verified promoter activity, however, it was unchanged by the identified SNPs after expressing respective reporter constructs in HeLa and human endothelial cells. CONCLUSION We suggest to consider the -44G>A SNP upstream of the connexin40 transcript 1A indeed as a risk factor for hypertension in men. However, the underlying mechanisms remain unclear but animal data suggest that renin-producing cells may be involved and contribute to hypertension.
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Affiliation(s)
- Kjestine Schmidt
- a Institut für Physiologie, Universität zu Lübeck , Lübeck , Germany
- b Deutsches Zentrum für Herz-Kreislauf-Forschung (DZHK) e.V. (German Center for Cardiovascular Research) , Lübeck , Germany
| | - Frank J Kaiser
- b Deutsches Zentrum für Herz-Kreislauf-Forschung (DZHK) e.V. (German Center for Cardiovascular Research) , Lübeck , Germany
- c Sektion für Funktionelle Genetik am Institut für Humangenetik, Universität zu Lübeck , Lübeck , Germany , and
| | - Jeanette Erdmann
- b Deutsches Zentrum für Herz-Kreislauf-Forschung (DZHK) e.V. (German Center for Cardiovascular Research) , Lübeck , Germany
- d Institut für Integrative und Experimentelle Genomik, Universität zu Lübeck , Lübeck , Germany
| | - Cor de Wit
- a Institut für Physiologie, Universität zu Lübeck , Lübeck , Germany
- b Deutsches Zentrum für Herz-Kreislauf-Forschung (DZHK) e.V. (German Center for Cardiovascular Research) , Lübeck , Germany
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Le Gal L, Alonso F, Mazzolai L, Meda P, Haefliger JA. Interplay between connexin40 and nitric oxide signaling during hypertension. Hypertension 2015; 65:910-5. [PMID: 25712722 DOI: 10.1161/hypertensionaha.114.04775] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Connexins (Cxs) and endothelial nitric oxide synthase (eNOS) contribute to the adaptation of endothelial and smooth muscle cells to hemodynamic changes. To decipher the in vivo interplay between these proteins, we studied Cx40-null mice, a model of renin-dependent hypertension which displays an altered endothelium-dependent relaxation of the aorta because of reduced eNOS levels. These mice, which were either untreated or subjected to the 1-kidney, 1-clip (1K1C) procedure, a model of volume-dependent hypertension, were compared with control mice submitted to either the 1K1C or the 2-kidney, 1-clip (2K1C) procedure, a model of renin-dependent hypertension. All operated mice became hypertensive and featured hypertrophy and altered Cx expression of the aorta. The combination of volume- and renin-dependent hypertension in Cx40-/- 1K1C mice raised blood pressure and cardiac weight index. Under these conditions, all aortas showed increased levels of Cx40 in endothelial cells and of both Cx37 and Cx45 in smooth muscle cells. In the wild-type 1K1C mice, the interactions between Cx40 and Cx37 with eNOS were enhanced, resulting in increased NO release. The Cx40-eNOS interaction could not be observed in mice lacking Cx40, which also featured decreased levels of eNOS. In these animals, the volume overload caused by the 1K1C procedure resulted in increased phosphorylation of eNOS and in a higher NO release. The findings provide evidence that Cx40 and Cx37 play an in vivo role in the regulation of eNOS.
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Affiliation(s)
- Loïc Le Gal
- From the Departments of Medicine (L.L.G., F.A., J.-A.H.) and Angiology (L.M.), Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, Switzerland; and Department of Cell Physiology and Metabolism, University of Geneva, Medical Center, Geneva, Switzerland (P.M.)
| | - Florian Alonso
- From the Departments of Medicine (L.L.G., F.A., J.-A.H.) and Angiology (L.M.), Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, Switzerland; and Department of Cell Physiology and Metabolism, University of Geneva, Medical Center, Geneva, Switzerland (P.M.)
| | - Lucia Mazzolai
- From the Departments of Medicine (L.L.G., F.A., J.-A.H.) and Angiology (L.M.), Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, Switzerland; and Department of Cell Physiology and Metabolism, University of Geneva, Medical Center, Geneva, Switzerland (P.M.)
| | - Paolo Meda
- From the Departments of Medicine (L.L.G., F.A., J.-A.H.) and Angiology (L.M.), Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, Switzerland; and Department of Cell Physiology and Metabolism, University of Geneva, Medical Center, Geneva, Switzerland (P.M.)
| | - Jacques-Antoine Haefliger
- From the Departments of Medicine (L.L.G., F.A., J.-A.H.) and Angiology (L.M.), Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, Switzerland; and Department of Cell Physiology and Metabolism, University of Geneva, Medical Center, Geneva, Switzerland (P.M.).
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