1
|
Gekle M, Dubourg V, Schwerdt G, Benndorf RA, Schreier B. The role of EGFR in vascular AT1R signaling: From cellular mechanisms to systemic relevance. Biochem Pharmacol 2023; 217:115837. [PMID: 37777161 DOI: 10.1016/j.bcp.2023.115837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/25/2023] [Accepted: 09/27/2023] [Indexed: 10/02/2023]
Abstract
The epidermal growth factor receptor (EGFR) belongs to the ErbB-family of receptor tyrosine kinases that are of importance in oncology. During the last years, substantial evidence accumulated for a crucial role of EGFR concerning the action of the angiotensin II type 1 receptor (AT1R) in blood vessels, resulting form AT1R-induced EGFR transactivation. This transactivation occurs through the release of membrane-anchored EGFR-ligands, cytosolic tyrosine kinases, heterocomplex formation or enhanced ligand expression. AT1R-EGFR crosstalk amplifies the signaling response and enhances the biological effects of angiotensin II. Downstream signaling cascades include ERK1/2 and p38 MAPK, PLCγ and STAT. AT1R-induced EGFR activation contributes to vascular remodeling and hypertrophy via e.g. smooth muscle cell proliferation, migration and extracellular matrix production. EGFR transactivation results in increased vessel wall thickness and reduced vascular compliance. AT1R and EGFR signaling pathways are also implicated the induction of vascular inflammation. Again, EGFR transactivation exacerbates the effects, leading to endothelial dysfunction that contributes to vascular inflammation, dysfunction and remodeling. Dysregulation of the AT1R-EGFR axis has been implicated in the pathogenesis of various cardiovascular diseases and inhibition or prevention of EGFR signaling can attenuate part of the detrimental impact of enhanced renin-angiotensin-system (RAAS) activity, highlighting the importance of EGFR for the adverse consequences of AT1R activation. In summary, EGFR plays a critical role in vascular AT1R action, enhancing signaling, promoting remodeling, contributing to inflammation, and participating in the pathogenesis of cardiovascular diseases. Understanding the interplay between AT1R and EGFR will foster the development of effective therapeutic strategies of RAAS-induced disorders.
Collapse
Affiliation(s)
- Michael Gekle
- Julius-Bernstein-Institute of Physiology, Martin-Luther-University Halle-Wittenberg, Magdeburger Str. 6, D-06112 Halle (Saale), Germany.
| | - Virginie Dubourg
- Julius-Bernstein-Institute of Physiology, Martin-Luther-University Halle-Wittenberg, Magdeburger Str. 6, D-06112 Halle (Saale), Germany
| | - Gerald Schwerdt
- Julius-Bernstein-Institute of Physiology, Martin-Luther-University Halle-Wittenberg, Magdeburger Str. 6, D-06112 Halle (Saale), Germany
| | - Ralf A Benndorf
- Institute of Pharmacy, Martin-Luther-University, Halle, Germany
| | - Barbara Schreier
- Julius-Bernstein-Institute of Physiology, Martin-Luther-University Halle-Wittenberg, Magdeburger Str. 6, D-06112 Halle (Saale), Germany
| |
Collapse
|
2
|
GPCR-mediated EGFR transactivation ameliorates skin toxicities induced by afatinib. Acta Pharmacol Sin 2022; 43:1534-1543. [PMID: 34552215 PMCID: PMC9160022 DOI: 10.1038/s41401-021-00774-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 09/05/2021] [Indexed: 02/07/2023] Open
Abstract
Many G-protein-coupled receptor (GPCR) agonists have been studied for transactivating epidermal growth factor receptor (EGFR) signaling through extracellular or intracellular pathways. Accumulated evidence has confirmed that GPCR transactivation participates in various diseases. However, the clinical application of GPCR transactivation has not been explored, and more translational studies are needed to develop therapies to target GPCR-mediated EGFR transactivation. In cancer patients treated with EGFR inhibitors (EGFRi), especially afatinib, a unique acneiform rash is frequently developed. In this study, we first established the connection between GPCR transactivation and EGFRi-induced skin disease. We examined the ability of three different GPCR agonists to reverse signaling inhibition and ameliorate rash induced by EGFRi. The activation of different agonists follows unique time and kinase patterns. Rats treated with EGFRi show a similar skin phenotype, with rash occurring in the clinic; correspondingly, treatment with GPCR agonists reduced keratinocyte apoptosis, growth retardation and infiltration of inflammatory cytokines by transactivation. This phenomenon demonstrates that EGFR inhibition in keratinocytes regulates key factors associated with rash. Our findings indicate that maintaining EGFR signaling by GPCR agonists might provide a possible therapy for EGFR inhibitor-induced skin toxicities. Our study provides the first example of the translational application of GPCR transactivation in treating diseases.
Collapse
|
3
|
Wu X, Du J, Song W, Cao M, Chen S, Xia R. Weak power frequency magnetic fields induce microtubule cytoskeleton reorganization depending on the epidermal growth factor receptor and the calcium related signaling. PLoS One 2018; 13:e0205569. [PMID: 30312357 PMCID: PMC6185734 DOI: 10.1371/journal.pone.0205569] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 09/27/2018] [Indexed: 01/14/2023] Open
Abstract
We have shown previously that a weak 50 Hz magnetic field (MF) invoked the actin-cytoskeleton, and provoked cell migration at the cell level, probably through activating the epidermal growth factor receptor (EGFR) related motility pathways. However, whether the MF also affects the microtubule (MT)-cytoskeleton is still unknown. In this article, we continuously investigate the effects of 0.4 mT, 50 Hz MF on the MT, and try to understand if the MT effects are also associated with the EGFR pathway as the actin-cytoskeleton effects were. Our results strongly suggest that the MF effects are similar to that of EGF stimulation on the MT cytoskeleton, showing that 1) the MF suppressed MT in multiple cell types including PC12 and FL; 2) the MF promoted the clustering of the EGFR at the protein and the cell levels, in a similar way of that EGF did but with higher sensitivity to PD153035 inhibition, and triggered EGFR phosphorylation on sites of Y1173 and S1046/1047; 3) these effects were strongly depending on the Ca2+ signaling through the L-type calcium channel (LTCC) phosphorylation and elevation of the intracellular Ca2+ level. Strong associations were observed between EGFR and the Ca2+ signaling to regulate the MF-induced-reorganization of the cytoskeleton network, via phosphorylating the signaling proteins in the two pathways, including a significant MT protein, tau. These results strongly suggest that the MF activates the overall cytoskeleton in the absence of EGF, through a mechanism related to both the EGFR and the LTCC/Ca2+ signaling pathways.
Collapse
Affiliation(s)
- Xia Wu
- Physics Department, East China Normal University, Shanghai, China
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, China
| | - Juan Du
- Physics Department, East China Normal University, Shanghai, China
| | - Weitao Song
- Physics Department, East China Normal University, Shanghai, China
| | - Meiping Cao
- Physics Department, East China Normal University, Shanghai, China
| | - Shude Chen
- Physics Department, East China Normal University, Shanghai, China
| | - Ruohong Xia
- Physics Department, East China Normal University, Shanghai, China
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, China
- * E-mail:
| |
Collapse
|
4
|
Forrester SJ, Kawai T, O'Brien S, Thomas W, Harris RC, Eguchi S. Epidermal Growth Factor Receptor Transactivation: Mechanisms, Pathophysiology, and Potential Therapies in the Cardiovascular System. Annu Rev Pharmacol Toxicol 2015; 56:627-53. [PMID: 26566153 DOI: 10.1146/annurev-pharmtox-070115-095427] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Epidermal growth factor receptor (EGFR) activation impacts the physiology and pathophysiology of the cardiovascular system, and inhibition of EGFR activity is emerging as a potential therapeutic strategy to treat diseases including hypertension, cardiac hypertrophy, renal fibrosis, and abdominal aortic aneurysm. The capacity of G protein-coupled receptor (GPCR) agonists, such as angiotensin II (AngII), to promote EGFR signaling is called transactivation and is well described, yet delineating the molecular processes and functional relevance of this crosstalk has been challenging. Moreover, these critical findings are dispersed among many different fields. The aim of our review is to highlight recent advancements in defining the signaling cascades and downstream consequences of EGFR transactivation in the cardiovascular renal system. We also focus on studies that link EGFR transactivation to animal models of the disease, and we discuss potential therapeutic applications.
Collapse
Affiliation(s)
- Steven J Forrester
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania 19140;
| | - Tatsuo Kawai
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania 19140;
| | - Shannon O'Brien
- The School of Biomedical Sciences, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Walter Thomas
- The School of Biomedical Sciences, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Raymond C Harris
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Satoru Eguchi
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania 19140;
| |
Collapse
|
5
|
Karnik SS, Unal H, Kemp JR, Tirupula KC, Eguchi S, Vanderheyden PML, Thomas WG. International Union of Basic and Clinical Pharmacology. XCIX. Angiotensin Receptors: Interpreters of Pathophysiological Angiotensinergic Stimuli [corrected]. Pharmacol Rev 2015; 67:754-819. [PMID: 26315714 PMCID: PMC4630565 DOI: 10.1124/pr.114.010454] [Citation(s) in RCA: 207] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The renin angiotensin system (RAS) produced hormone peptides regulate many vital body functions. Dysfunctional signaling by receptors for RAS peptides leads to pathologic states. Nearly half of humanity today would likely benefit from modern drugs targeting these receptors. The receptors for RAS peptides consist of three G-protein-coupled receptors—the angiotensin II type 1 receptor (AT1 receptor), the angiotensin II type 2 receptor (AT2 receptor), the MAS receptor—and a type II trans-membrane zinc protein—the candidate angiotensin IV receptor (AngIV binding site). The prorenin receptor is a relatively new contender for consideration, but is not included here because the role of prorenin receptor as an independent endocrine mediator is presently unclear. The full spectrum of biologic characteristics of these receptors is still evolving, but there is evidence establishing unique roles of each receptor in cardiovascular, hemodynamic, neurologic, renal, and endothelial functions, as well as in cell proliferation, survival, matrix-cell interaction, and inflammation. Therapeutic agents targeted to these receptors are either in active use in clinical intervention of major common diseases or under evaluation for repurposing in many other disorders. Broad-spectrum influence these receptors produce in complex pathophysiological context in our body highlights their role as precise interpreters of distinctive angiotensinergic peptide cues. This review article summarizes findings published in the last 15 years on the structure, pharmacology, signaling, physiology, and disease states related to angiotensin receptors. We also discuss the challenges the pharmacologist presently faces in formally accepting newer members as established angiotensin receptors and emphasize necessary future developments.
Collapse
Affiliation(s)
- Sadashiva S Karnik
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Hamiyet Unal
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Jacqueline R Kemp
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Kalyan C Tirupula
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Satoru Eguchi
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Patrick M L Vanderheyden
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Walter G Thomas
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| |
Collapse
|
6
|
Abstract
Mammalian sperm acquire fertilization capacity after residing in the female reproductive tract for a few hours in a process called capacitation. Only capacitated sperm can bind the zona pellucida (ZP) of the egg and undergo the acrosome reaction, a process that allows penetration and fertilization. Extracellular signal regulated kinase (ERK1/2) mediates signalling in many cell types, however its role in sperm function is largely unknown. Here we show that ERK1/2 is highly phosphorylated/activated after a short incubation of mouse sperm under capacitation conditions and that this phosphorylation is reduced after longer incubation. Further phosphorylation was observed upon addition of crude extract of egg ZP or epidermal growth factor (EGF). The mitogen-activated ERK-kinase (MEK) inhibitor U0126 abolished ERK1/2 phosphorylation, in vitro fertilization rate and the acrosome reaction induced by ZP or EGF but not by the Ca2+-ionophore A23187. Moreover, inhibition of ERK1/2 along the capacitation process diminished almost completely the sperm's ability to go through the acrosome reaction, while inhibition at the end of capacitation attenuated the acrosome reaction rate by only 45%. The fact that the acrosome reaction, induced by the Ca2+ -ionophore A23187, was not inhibited by U0126 suggests that ERK1/2 mediates the acrosome reaction by activating Ca2+ transport into the cell. Direct determination of intracellular [Ca2+] revealed that Ca2+ influx induced by EGF or ZP was completely blocked by U0126. Thus, it has been established that the increase in ERK1/2 phosphorylation/activation in response to ZP or by activation of the EGF receptor (EGFR) by EGF, is a key event for intracellular Ca2+ elevation and the subsequent occurrence of the acrosome reaction.
Collapse
|
7
|
Wu X, Cao MP, Shen YY, Chu KP, Tao WB, Song WT, Liu LP, Wang XH, Zheng YF, Chen SD, Zeng QL, Xia RH. Weak power frequency magnetic field acting similarly to EGF stimulation, induces acute activations of the EGFR sensitive actin cytoskeleton motility in human amniotic cells. PLoS One 2014; 9:e87626. [PMID: 24505297 PMCID: PMC3914819 DOI: 10.1371/journal.pone.0087626] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Accepted: 12/16/2013] [Indexed: 12/30/2022] Open
Abstract
In this article, we have examined the motility-related effects of weak power frequency magnetic fields (MFs) on the epidermal growth factor receptor (EGFR)-sensitive motility mechanism, including the F-actin cytoskeleton, growth of invasive protrusions and the levels of signal molecules in human amniotic epithelial (FL) cells. Without extracellular EGF stimulation, the field stimulated a large growth of new protrusions, especially filopodia and lamellipodia, an increased population of vinculin-associated focal adhesions. And, an obvious reduction of stress fiber content in cell centers was found, corresponding to larger cell surface areas and decreased efficiency of actin assembly of FL cells in vitro, which was associated with a decrease in overall F-actin content and special distributions. These effects were also associated with changes in protein content or distribution patterns of the EGFR downstream motility-related signaling molecules. All of these effects are similar to those following epidermal growth factor (EGF) stimulation of the cells and are time dependent. These results suggest that power frequency MF exposure acutely affects the migration/motility-related actin cytoskeleton reorganization that is regulated by the EGFR-cytoskeleton signaling pathway. Therefore, upon the MF exposure, cells are likely altered to be ready to transfer into a state of migration in response to the stimuli.
Collapse
Affiliation(s)
- Xia Wu
- Physics Department, East China Normal University, Shanghai, China
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, China
| | - Mei-Ping Cao
- Physics Department, East China Normal University, Shanghai, China
| | - Yun-Yun Shen
- Bioelectromagnetics Laboratory, Zhejiang University, Hangzhou, China
| | - Ke-Ping Chu
- Physics Department, East China Normal University, Shanghai, China
| | - Wu-Bin Tao
- Physics Department, East China Normal University, Shanghai, China
| | - Wei-Tao Song
- Physics Department, East China Normal University, Shanghai, China
| | - Li-Ping Liu
- School of Life Sciences, Fudan University, Shanghai, China
| | - Xiang-Hui Wang
- Physics Department, East China Normal University, Shanghai, China
| | - Yu-Fang Zheng
- School of Life Sciences, Fudan University, Shanghai, China
| | - Shu-De Chen
- Physics Department, East China Normal University, Shanghai, China
| | - Qun-Li Zeng
- Bioelectromagnetics Laboratory, Zhejiang University, Hangzhou, China
| | - Ruo-Hong Xia
- Physics Department, East China Normal University, Shanghai, China
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, China
| |
Collapse
|
8
|
Abstract
Epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase. Its activation results in beneficial or detrimental consequences, depending on the particular setting. Earlier studies in the animal model of acute kidney injury showed that EGFR activation promotes renal tubular cell proliferation. Activation of EGFR by its exogenous ligands, like EGF, can enhance recovery of renal function and structure following acute kidney injury. However, recent studies indicated that EGFR activation also contributes to development and progression of renal diseases in animal models of obstructive nephropathy, diabetic nephropathy, hypertensive nephropathy, and glomerulonephritis through mechanisms involved in activation of renal interstitial fibroblasts, induction of tubular atrophy, overproduction of inflammatory factors, and/or promotion of glomerular and vascular injury. This review highlights the actions and mechanisms of EGFR in a variety of acute and chronic kidney injuries.
Collapse
|
9
|
Qu WS, Tian DS, Guo ZB, Fang J, Zhang Q, Yu ZY, Xie MJ, Zhang HQ, Lü JG, Wang W. Inhibition of EGFR/MAPK signaling reduces microglial inflammatory response and the associated secondary damage in rats after spinal cord injury. J Neuroinflammation 2012; 9:178. [PMID: 22824323 PMCID: PMC3418570 DOI: 10.1186/1742-2094-9-178] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Accepted: 07/02/2012] [Indexed: 02/08/2023] Open
Abstract
Background Emerging evidence indicates that reactive microglia-initiated inflammatory responses are responsible for secondary damage after primary traumatic spinal cord injury (SCI); epidermal growth factor receptor (EGFR) signaling may be involved in cell activation. In this report, we investigate the influence of EGFR signaling inhibition on microglia activation, proinflammatory cytokine production, and the neuronal microenvironment after SCI. Methods Lipopolysaccharide-treated primary microglia/BV2 line cells and SCI rats were used as model systems. Both C225 and AG1478 were used to inhibit EGFR signaling activation. Cell activation and EGFR phosphorylation were observed after fluorescent staining and western blot. Production of interleukin-1beta (IL-1β) and tumor necrosis factor alpha (TNFα) was tested by reverse transcription PCR and ELISA. Western blot was performed to semi-quantify the expression of EGFR/phospho-EGFR, and phosphorylation of Erk, JNK and p38 mitogen-activated protein kinases (MAPK). Wet-dry weight was compared to show tissue edema. Finally, axonal tracing and functional scoring were performed to show recovery of rats. Results EGFR phosphorylation was found to parallel microglia activation, while EGFR blockade inhibited activation-associated cell morphological changes and production of IL-1β and TNFα. EGFR blockade significantly downregulated the elevated MAPK activation after cell activation; selective MAPK inhibitors depressed production of cytokines to a certain degree, suggesting that MAPK mediates the depression of microglia activation brought about by EGFR inhibitors. Subsequently, seven-day continual infusion of C225 or AG1478 in rats: reduced the expression of phospho-EGFR, phosphorylation of Erk and p38 MAPK, and production of IL-1β and TNFα; lessened neuroinflammation-associated secondary damage, like microglia/astrocyte activation, tissue edema and glial scar/cavity formation; and enhanced axonal outgrowth and functional recovery. Conclusions These findings indicate that inhibition of EGFR/MAPK suppresses microglia activation and associated cytokine production; reduces neuroinflammation-associated secondary damage, thus provides neuroprotection to SCI rats, suggesting that EGFR may be a therapeutic target, and C225 and AG1478 have potential for use in SCI treatment.
Collapse
Affiliation(s)
- Wen-Sheng Qu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Passmore JC, Fleming JT, Tyagi SC, Falcone JC. Tyrosine kinase receptor alteration of renal vasoconstriction in rats is sex- and age-related. Can J Physiol Pharmacol 2012; 90:1372-9. [PMID: 22724583 DOI: 10.1139/y2012-093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Male rat renal blood vessels undergo reduced contraction to norepinephrine with aging. There is a greater renal vascular impairment in male compared with female rats. We investigated specific tyrosine kinase receptor inhibition of renal interlobar artery responsiveness to phenylephrine in male and female rats at specifically designated ages. Vessels from young male rats contracted much less to phenylephrine when the vessels were pretreated with the tyrosine kinase inhibitors Lavendustin A, HNMPA-(AM)₃, or AG1478. Vessels from adult female rats pretreated with Lavendustin A showed no difference in contraction from control, but did demonstrate a slightly reduced contraction when pretreated with AG1478. Middle-aged male rat vessels treated with Lavendustin A demonstrated no inhibition, but the insulin and epidermal growth factor receptor (EGFR) antagonists both induced a decline in contraction. Vessels from aged male rats demonstrated no effect related to the 3 pretreatments. Middle-aged and aged female rats pretreated with any inhibitor demonstrated no inhibitor-dependent alterations. We conclude that maximum contraction of interlobar arteries from adult male rats is reduced when tyrosine kinase receptor activity is reduced. Female rats demonstrated much less inhibitor-related change of contraction.
Collapse
Affiliation(s)
- John C Passmore
- Department of Physiology and Biophysics, Health Sciences Center, University of Louisville School of Medicine, 500 South Preston St., Louisville, KY 409292, USA.
| | | | | | | |
Collapse
|
11
|
Yang Q, Wang EY, Huang XJ, Qu WS, Zhang L, Xu JZ, Wang W, Tian DS. Blocking epidermal growth factor receptor attenuates reactive astrogliosis through inhibiting cell cycle progression and protects against ischemic brain injury in rats. J Neurochem 2011; 119:644-53. [DOI: 10.1111/j.1471-4159.2011.07446.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
12
|
Schreier B, Döhler M, Rabe S, Schneider B, Schwerdt G, Ruhs S, Sibilia M, Gotthardt M, Gekle M, Grossmann C. Consequences of epidermal growth factor receptor (ErbB1) loss for vascular smooth muscle cells from mice with targeted deletion of ErbB1. Arterioscler Thromb Vasc Biol 2011; 31:1643-52. [PMID: 21512163 DOI: 10.1161/atvbaha.111.223537] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
OBJECTIVE Pathophysiological effects of the epidermal growth factor receptor (EGFR or ErbB1) include vascular remodeling. EGFR transactivation is proposed to contribute significantly to heterologous signaling and remodeling in vascular smooth muscle cells (VSMC). METHODS AND RESULTS We investigated the importance of EGFR in primary VSMC from aorta of mice with targeted deletion of the EGFR (EGFR(Δ/Δ VSMC)→VSMC(EGFR-/-) and EGFR(Δ/+ VSMC)→VSMC(EGFR+/-)) and the respective littermate controls (EGFR(+/+ VSMC)→VSMC(EGFR+/+)) with respect to survival, pentose phosphate pathway activity, matrix homeostasis, extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation, and Ca(2+) homeostasis. In VSMC(EGFR-/-), epidermal growth factor-induced signaling was abolished; VSMC(EGFR+/-) showed an intermediate phenotype. EGFR deletion enhanced spontaneous cell death, reduced pentose phosphate pathway activity, disturbed cellular matrix homeostasis (collagen III and fibronectin), and abolished epidermal growth factor sensitivity. In VSMC(EGFR-/-) endothelin-1- or α(1)-adrenoceptor-induced ERK1/2 phosphorylation and the fraction of Ca(2+) responders were significantly reduced, whereas responsive cells showed a significantly stronger Ca(2+) signal. Oxidative stress (H(2)O(2)) induced ERK1/2 activation in VSMC(EGFR+/+) and VSMC(EGFR+/-) but not in VSMC(EGFR-/-). The Ca(2+) signal was enhanced in VSMC(EGFR-/-), similar to purinergic stimulation by ATP. CONCLUSIONS In conclusion, EGFR was found to be important for basal VSMC homeostasis and ERK1/2 activation by the tested G-protein-coupled receptors or radical stress. Ca(2+) signaling was modulated by EGFR differentially with respect to the fraction of responders and magnitude of the signal. Thus, EGFR seems to be Janus-faced for VSMC biology.
Collapse
Affiliation(s)
- Barbara Schreier
- Julius-Bernstein-Institute of Physiology, University of Halle-Wittenberg, Halle, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Helle F, Jouzel C, Chadjichristos C, Placier S, Flamant M, Guerrot D, François H, Dussaule JC, Chatziantoniou C. Improvement of renal hemodynamics during hypertension-induced chronic renal disease: role of EGF receptor antagonism. Am J Physiol Renal Physiol 2009; 297:F191-9. [DOI: 10.1152/ajprenal.00015.2009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The present study investigated mechanisms of regression of renal disease after severe proteinuria by focusing on the interaction among EGF receptors, renal hemodynamics, and structural lesions. The nitric oxide (NO) inhibitor NG-nitro-l-arginine-methyl ester (l-NAME) was administered chronically in Sprague-Dawley rats. When proteinuria exceeded 2 g/mmol creatinine, animals were divided into three groups for an experimental period of therapy of 2 wk; in one group, l-NAME was removed to allow reactivation of endogenous NO synthesis; in the two other groups, l-NAME removal was combined with EGF or angiotensin receptor type 1 (AT1) antagonism. l-NAME removal partially reduced mean arterial pressure and proteinuria and increased renal blood flow (RBF), but not microvascular hypertrophy. Progression of structural damage was stopped, but not reversed. The administration of an EGF receptor antagonist did not have an additional effect on lowering blood pressure or on renal inflammation but did normalize RBF and afferent arteriole hypertrophy; the administration of an AT1 antagonist normalized all measured functional and structural parameters. Staining with a specific marker of endothelial integrity indicated loss of functional endothelial cells in the l-NAME removal group; in contrast, in the animals treated with an EGF or AT1 receptor antagonist, functional endothelial cells reappeared at levels equal to control animals. In addition, afferent arterioles freshly isolated from the l-NAME removal group showed an exaggerated constrictor response to endothelin; this response was blunted in the vessels isolated from the EGF or AT1 receptor antagonist groups. The EGF receptor is an important mediator of endothelial dysfunction and contributes to the decline of RBF in the chronic kidney disease induced by NO deficiency. The EGF receptor antagonist-induced improvement of RBF is important but not sufficient for a complete reversal of renal disease, because it has little effect on renal inflammation. To achieve full recovery, it is necessary to apply AT1 receptor antagonism.
Collapse
|
14
|
Melenhorst WBWH, Mulder GM, Xi Q, Hoenderop JGJ, Kimura K, Eguchi S, van Goor H. Epidermal growth factor receptor signaling in the kidney: key roles in physiology and disease. Hypertension 2008; 52:987-93. [PMID: 18981331 DOI: 10.1161/hypertensionaha.108.113860] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Wynand B W H Melenhorst
- Department of Pathology and Medical Biology, University Medical Center Groningen, Groningen, The Netherlands.
| | | | | | | | | | | | | |
Collapse
|
15
|
Yin X, Li B, Chen H, Catt KJ. Differential signaling pathways in angiotensin II- and epidermal growth factor-stimulated hepatic C9 cells. Mol Pharmacol 2008; 74:1223-33. [PMID: 18687808 DOI: 10.1124/mol.108.048504] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Caveolin1 (Cav1) is an important component of the plasmamembrane microdomains, such as caveolae/lipid rafts, that are associated with angiotensin II type 1 (AT(1)) and epidermal growth factor (EGF) receptors in certain cell types. The interactions of Cav1 with other signaling molecules that mediate AT(1) receptor function were analyzed in angiotensin II (Ang II)- and EGF-stimulated hepatic C9 cells. This study demonstrated that cholesterol-rich domains mediate the actions of early upstream signaling molecules such as Src and intracellular Ca(2+) in cells stimulated by Ang II, but not by EGF, and that Cav1 has a scaffolding role in the process of mitogen-activated protein kinase activation. Furthermore, Cav1 phosphorylation by Ang II and EGF was regulated by intracellular Ca(2+) and Src, further indicating reciprocal interactions among Cav1, Src, and intracellular Ca(2+) through the AT(1) receptor. Phosphorylation of Cav1 and the EGF receptor by Ang II, but not of extracellular signal-regulated kinase 1/2, was dependent on intracellular Ca(2+). The phosphatidylinositol 3-kinase inhibitors, 2-(4-morpholinyl)-8-phenyl-1(4H)-benzopyran-4-one hydrochloride (LY294002) and wortmannin, differentially modulated both Cav1 and EGF receptor activation by Ang II through intracellular Ca(2+). These findings further demonstrate the importance of Cav1 in conjunction with the receptor-mediated signaling pathways involved in cell proliferation and survival. It is clear that differential signaling pathways are operative in Ang II- and EGF-stimulated C9 cells and that cholesterol-enriched microdomains are essential components in cellular signaling processes that are dependent on specific agonists and/or cell types.
Collapse
Affiliation(s)
- Xing Yin
- Endocrinology and Reproduction Research Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | | | | | | |
Collapse
|
16
|
Yano N, Suzuki D, Endoh M, Zhao TC, Padbury JF, Tseng YT. A novel phosphoinositide 3-kinase-dependent pathway for angiotensin II/AT-1 receptor-mediated induction of collagen synthesis in MES-13 mesangial cells. J Biol Chem 2007; 282:18819-30. [PMID: 17493931 DOI: 10.1074/jbc.m610537200] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Chronic activation of the angiotensin II (ANG II) type 1 receptor (AT-1R) is critical in the development of chronic kidney disease. ANG II activates mesangial cells (MCs) and stimulates the synthesis of extracellular matrix components. To determine the molecular mechanisms underlying the induction of MC collagen, a mouse mesangial cell line MES-13 was employed. ANG II treatment induced an increase in collagen synthesis, which was abrogated by co-treatment with losartan (an AT-1R antagonist), wortmannin (a phosphoinositide 3-kinase (PI3K) inhibitor), an Akt inhibitor, and stable transfection of dominant negative-Akt1. ANG II induced a significant increase in PI3K activity, which was abolished by co-treatment with losartan or 2',5'-dideoxyadenosine (2',5'-DOA, an adenylyl cyclase inhibitor) but not by PD123319 (an AT-2R antagonist) or H89 (a protein kinase A (PKA) inhibitor). The Epac (exchange protein directly activated by cAMP)-specific cAMP analog, 8-pHPT-2'-O-Me-cAMP, significantly increased PI3K activity, whereas a PKA-specific analog, 6-benzoyladenosine-cAMP, showed no effect. The ANG II-induced increase in PI3K activity was also blocked by co-treatment with PP2, an Src inhibitor, or AG1478, an epidermal growth factor receptor (EGFR) antagonist. ANG II induced phosphorylation of Akt and p70S6K and EGFR, which was abrogated by knockdown of c-Src by small interference RNA. Knockdown of Src also effectively abolished ANG II-induced collagen synthesis. Conversely, stable transfection of a constitutively active Src mutant enhanced basal PI3K activity and collagen production, which was abrogated by AG1478 but not by 2',5'-DOA. Moreover, acute treatment with ANG II significantly increased Src activity, which was abrogated with co-treatment of 2',5'-DOA. Taken together, these results suggest that ANG II induces collagen synthesis in MCs by activating the ANG II/AT-1R-EGFR-PI3K pathway. This transactivation is dependent on cAMP/Epac but not on PKA. Src kinase plays a pivotal role in this signaling pathway between cAMP and EGFR. This is the first demonstration that an AT1R-PI3K/Akt crosstalk, along with transactivation of EGFR, mediates ANG II-induced collagen synthesis in MCs.
Collapse
Affiliation(s)
- Naohiro Yano
- Department of Pediatrics, Women and Infant's Hospital, The Warren Alpert Medical School, Brown University, Providence, Rhode Island 02905, USA
| | | | | | | | | | | |
Collapse
|
17
|
Higuchi S, Ohtsu H, Suzuki H, Shirai H, Frank GD, Eguchi S. Angiotensin II signal transduction through the AT1 receptor: novel insights into mechanisms and pathophysiology. Clin Sci (Lond) 2007; 112:417-28. [PMID: 17346243 DOI: 10.1042/cs20060342] [Citation(s) in RCA: 320] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The intracellular signal transduction of AngII (angiotensin II) has been implicated in cardiovascular diseases, such as hypertension, atherosclerosis and restenosis after injury. AT(1) receptor (AngII type-1 receptor), a G-protein-coupled receptor, mediates most of the physiological and pathophysiological actions of AngII, and this receptor is predominantly expressed in cardiovascular cells, such as VSMCs (vascular smooth muscle cells). AngII activates various signalling molecules, including G-protein-derived second messengers, protein kinases and small G-proteins (Ras, Rho, Rac etc), through the AT(1) receptor leading to vascular remodelling. Growth factor receptors, such as EGFR (epidermal growth factor receptor), have been demonstrated to be 'trans'-activated by the AT(1) receptor in VSMCs to mediate growth and migration. Rho and its effector Rho-kinase/ROCK are also implicated in the pathological cellular actions of AngII in VSMCs. Less is known about the endothelial AngII signalling; however, recent studies suggest the endothelial AngII signalling positively, as well as negatively, regulates the NO (nitric oxide) signalling pathway and, thereby, modulates endothelial dysfunction. Moreover, selective AT(1)-receptor-interacting proteins have recently been identified that potentially regulate AngII signal transduction and their pathogenic functions in the target organs. In this review, we focus our discussion on the recent findings and concepts that suggest the existence of the above-mentioned novel signalling mechanisms whereby AngII mediates the formation of cardiovascular diseases.
Collapse
Affiliation(s)
- Sadaharu Higuchi
- Cardiovascular Research Center, Department of Physiology, Temple University School of Medicine, Philadelphia, PA 19140, USA
| | | | | | | | | | | |
Collapse
|
18
|
Ying WZ, Zhang HG, Sanders PW. EGF receptor activity modulates apoptosis induced by inhibition of the proteasome of vascular smooth muscle cells. J Am Soc Nephrol 2006; 18:131-42. [PMID: 17151333 DOI: 10.1681/asn.2006040333] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The observation that intracellular protein turnover rates participate directly in cell viability led to the development and clinical use of potent proteasome inhibitors. This study determined that the mechanism of apoptosis that is induced by inhibition of the proteasome of vascular smooth muscle cells (VSMC) was related to the intracellular accumulation of Bad, a BH3-only member of the Bcl-2 family of apoptosis regulators. Experiments confirmed that the apoptotic process was mitochondria- and caspase-dependent. Ubiquitination and accumulation of Bad in VSMC followed inhibition of the proteasome, and depletion of Bad using RNA interference prevented apoptosis that was induced by proteasome inhibition with PS-341. EGF receptor (EGFR) activation produced posttranslational modifications of Bad, providing the pro-survival signals that prevented apoptosis of smooth muscle cells during proteasome inhibition. Antagonists of the EGFR potentiated the apoptotic rate. In summary, the activities of the EGFR and the proteasome focused on Bad and the intrinsic apoptotic pathway and were involved integrally in determining viability of VSMC. These findings might prove useful in the management of diseases in which proliferation of vascular smooth muscle cells plays a central role.
Collapse
MESH Headings
- Animals
- Apoptosis/drug effects
- Apoptosis/physiology
- Boronic Acids/pharmacology
- Bortezomib
- Caspases/metabolism
- Cell Proliferation
- Cells, Cultured
- ErbB Receptors/antagonists & inhibitors
- ErbB Receptors/metabolism
- Mitochondria/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Myocytes, Smooth Muscle/cytology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Protease Inhibitors/pharmacology
- Proteasome Inhibitors
- Protein Processing, Post-Translational
- Pyrazines/pharmacology
- Quinazolines/pharmacology
- RNA Interference
- Rats
- bcl-Associated Death Protein/antagonists & inhibitors
- bcl-Associated Death Protein/genetics
- bcl-Associated Death Protein/metabolism
Collapse
Affiliation(s)
- Wei-Zhong Ying
- Division of Nephrology/Department of Medicine, niversity of Alabama at Birmingham, Birmingham, AL 35294-0007, USA
| | | | | |
Collapse
|
19
|
Chansel D, Ciroldi M, Vandermeersch S, Jackson LF, Gomez AM, Henrion D, Lee DC, Coffman TM, Richard S, Dussaule JC, Tharaux PL. Heparin binding EGF is necessary for vasospastic response to endothelin. FASEB J 2006; 20:1936-8. [PMID: 16877529 DOI: 10.1096/fj.05-5328fje] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Endothelin-1 (ET-1), a powerful vasoconstrictor, is involved in vasospastic diseases such as coronary artery disease and subarachnoidal hemorrhage, as well as in renal and cardiovascular fibrotic remodeling. Transactivation of the epidermal growth factor receptor (EGFR) mediates ET-1 signaling in vascular smooth muscle cells (VSMCs) and isolated arteries. Moreover, EGFR is required for a full constrictive response to ET-1. However, the relevant mechanisms mediating EGFR transactivation in response to ET-1 have not been identified. The present study used isolated arteries and VSMCs to investigate the role of the EGFR ligand heparin binding-epidermal growth factor (HB-EGF) in ET-1-induced transactivation of EGFR, intracellular calcium mobilization, and VSMCs contraction. While baseline blood pressures were similar in HB-EGF-deficient and in wild-type littermate mice, the vasoconstrictor actions of ET-1 were attenuated in HB-EGF-/- animals. In isolated mouse carotid artery segments mounted in an arteriograph, ET-1 caused only a weak increase in isovolumetric tone in HB-EGF-deficient vessels, and this effect was mimicked by inhibition of EGFR tyrosine kinase or phosphoinositide 3-kinase (PI3K) in wild-type arteries with or without endothelium, indicating a specific role in VSMCs. EGFR or PI3K inhibitors had no effect on KCl-induced contraction, which was normal in HB-EGF-deficient mice. To confirm that the abnormal responses in HB-EGF-deficient mice were due to impaired EGFR signaling, we studied VSMCs from waved-2 (wa2) mice; these animals have a mutation causing a partial loss of function of EGFR tyrosine kinase activity. The ET-1-induced calcium peak was reduced by 30% in VSMCs from wa2 mice and from HB-EGF-/- mice. This effect was reproduced by preincubation of wild-type VSMCs with EGFR inhibitor AG1478 and PI3K inhibitors LY294002 and wortmannin. ProHB-EGF is bound to the cell membrane and released after cleavage by metalloproteinases; its action may contribute to effects of GPCR agonists on cell growth. Pretreatment of mouse VSMCs with batimastat, a metalloproteinase inhibitor, significantly attenuated ET-1-induced [Ca(2+)](i) response in wild-type cells. Human proHB-EGF has been shown to be the endogenous receptor for Corynebacterium diphteriae toxin (DT). Mutated DT toxin (CRM197) is devoid of toxicity but it neutralizes HB-EGF binding to EGFR. Pretreatment of human VSMCs from internal mammary arteries with CRM197 significantly blunted ET-1-stimulated calcium transients. In conclusion, these findings suggest that the mechanism of ET-1-induced vasoconstriction involves HB-EGF-mediated transactivation of the EGFR. This functional cascade requires modulation of agonist-induced calcium transient by EGFR and PI3K with extremely fast kinetics, suggesting a novel paradigm for GPCR-mediated calcium signaling, which may offer future therapeutic targets.
Collapse
Affiliation(s)
- Dominique Chansel
- INSERM U702; Hôpital Tenon; Université Pierre et Marie Curie, Paris, France
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Passmore JC, Joshua IG, Rowell PP, Tyagi SC, Falcone JC. Reduced alpha adrenergic mediated contraction of renal preglomerular blood vessels as a function of gender and aging. J Cell Biochem 2006; 96:672-81. [PMID: 16149078 DOI: 10.1002/jcb.20581] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
As human males age, a decline in baroreflex-mediated elevation of blood pressure occurs due, at least in part, to a reduction in alpha-1 adrenergic vasoconstrictor function. Alpha adrenergic constriction is mediated by guanosine triphosphate binding Protein (G Protein) coupled signaling pathways. Alpha-1 A/C, B, and D adrenergic receptor expressions, measured by GeneChip array, are not reduced during aging in renal blood vessels of male or female rats. Alpha-1 A GeneChip expression is greater, at all ages studied, in females than in males. Prazosin binding by alpha-1 adrenergic receptors is greater in young adult female rats than in young adult male rats; however, it is reduced with aging in both male and female rats. G alpha q GeneChip expression declines while expression of adrenergic receptor kinase (GRK2) and tyrosine phosphatases (TyrP) increase with aging in male rats. The declines in alpha-1 adrenergic receptor binding and G alpha q expression and also the increases in GRK2 and TyrP expression likely relate to the age-related decline of vasoconstriction in male rats. The information that the expression of alpha-1 A adrenergic receptors is greater in female rats and (GRK2) expression does not increase during aging could relate to the gender differences in vasoconstrictor function with aging. Gene therapy to ameliorate the age-related decline in renal function could possibly reduce the need for renal dialysis. Signaling pathways such as those reviewed herein may provide an outline of the molecular pathways needed to move toward successful renal gene therapy for aging individuals.
Collapse
Affiliation(s)
- John C Passmore
- Department of Physiology and Biophysics, School of Medicine, University of Louisville, Louisville, Kentucky 40292, USA.
| | | | | | | | | |
Collapse
|
21
|
Fellner SK, Arendshorst WJ. Angiotensin II, reactive oxygen species, and Ca2+signaling in afferent arterioles. Am J Physiol Renal Physiol 2005; 289:F1012-9. [PMID: 15942049 DOI: 10.1152/ajprenal.00144.2005] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In afferent arteriolar vascular smooth muscle cells, ANG II induces a rise in cytosolic Ca2+([Ca2+]i) via inositol trisphosphate receptor (IP3R) stimulation and by activation of the adenine diphosphate ribose (ADPR) cyclase to form cyclic ADPR, which sensitizes the ryanodine receptor (RyR) to Ca2+. We hypothesize that ANG II stimulation of NAD(P)H oxidases leads to the formation of superoxide anion (O2−·), which, in turn, activates ADPR cyclase. Afferent arterioles were isolated from rat kidney with the magnetized microsphere and sieving technique and loaded with fura-2 to measure [Ca2+]i. ANG II rapidly increased [Ca2+]iby 124 ± 12 nM. In the presence of apocynin, a specific inhibitor of NAD(P)H oxidase assembly, the [Ca2+]iresponse was reduced to 35 ± 5 nM ( P < 0.01). Tempol, a superoxide dismutase mimetic, did not alter the [Ca2+]iresponse to ANG II at a concentration of 10−4M (99 ± 12 nM), but 10−3M tempol reduced the response to 32 ± 3 nM ( P < 0.01). The addition of nicotinamide, an inhibitor of ADPR cyclase, to apocynin or tempol (10−3M) resulted in no further inhibition. Measurement of superoxide production with the fluorescent probe tempo 9-AC showed that ANG II caused an increase of 48 ± 20 arbitrary units; apocynin or diphenyl iodonium (an inhibitor of flavoprotein oxidases) inhibited the response by 94%. Hydrogen peroxide (H2O2) was studied at physiological (10−7M) and higher concentrations. In the presence of H2O2(10−7M), neither baseline [Ca2+]inor the response to ANG II was altered (125 ± 15 nM), whereas H2O2(10−6and 10−5M) inhibited the [Ca2+]iresponse to ANG II by 35 and 46%, respectively. We conclude that ANG II rapidly activates NAD(P)H oxidases of afferent arterioles, leading to the formation of O2−·, which then stimulates ADPR cyclase to form cADPR. cADPR, by sensitizing the RyR to Ca2+, augments the Ca2+response (calcium-induced calcium release) initiated by activation of the IP3R.
Collapse
Affiliation(s)
- Susan K Fellner
- Dept. of Cell and Molecular Physiology, University of North Carolina, Chapel Hill, NC 27599-7545, USA.
| | | |
Collapse
|
22
|
Flamant M, Dussaule JC, Ardaillou R. Les effets profibrosants des peptides vasoactifs dans le rein et les vaisseaux passent-ils par la transactivation du facteur de croissance épidermique (EGF)? Med Sci (Paris) 2005; 21:461-3. [PMID: 15885190 DOI: 10.1051/medsci/2005215461] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
|
23
|
Ying WZ, Sanders PW. Enhanced expression of EGF receptor in a model of salt-sensitive hypertension. Am J Physiol Renal Physiol 2005; 289:F314-21. [PMID: 15827348 DOI: 10.1152/ajprenal.00003.2005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Chronic kidney disease in the Dahl/Rapp salt-sensitive (S) rat is related to an arteriolopathic process that occurs following the onset of hypertension and involves vascular smooth muscle cell (VSMC) hyperplasia and luminal constriction. Because previous studies have shown that activation of the epidermal growth factor receptor (EGFR) produces a mitogenic stimulus in VSMC and the EGFR participates integrally in the vasoconstrictor responses of renal arterioles, the present study analyzed the expression of EGFR in these animals. Compared with Sprague-Dawley (SD) rats, renal cortical expression of EGFR was increased in both prehypertensive and hypertensive S rats. Immunohistochemistry using a polyclonal antibody to EGFR demonstrated that EGFR expression was prominent in the renal vasculature, particularly in the media of afferent and efferent arterioles and the aorta of S rats. When examined, primary cultures of VSMC from S rats showed increased expression of EGFR, compared with VSMC from SD and Dahl/Rapp salt-resistant rats. Following addition of EGF, autophosphorylation of the EGFR was enhanced in cells from S rats, as was the downstream signaling events that included activation of p42/44 MAPK and Akt pathways. Thus in vivo and in vitro studies demonstrated augmented expression and functional activity of the EGFR in S rats.
Collapse
MESH Headings
- Animals
- Blotting, Northern
- Blotting, Western
- Cells, Cultured
- ErbB Receptors/biosynthesis
- Flow Cytometry
- Hypertension/chemically induced
- Hypertension/metabolism
- Immunohistochemistry
- Kidney/metabolism
- Kidney Cortex/drug effects
- Kidney Cortex/metabolism
- Male
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- RNA, Messenger/biosynthesis
- Rats
- Rats, Inbred Dahl
- Rats, Sprague-Dawley
- Signal Transduction/drug effects
- Sodium Chloride/pharmacology
Collapse
Affiliation(s)
- Wei-Zhong Ying
- Nephrology Research and Training Center, Comprehensive Cancer Center, University of Alabama at Birmingham, 35294-0007, USA
| | | |
Collapse
|
24
|
Rohra DK, Yamakuni T, Ohizumi Y. Acidosis-induced protein tyrosine phosphorylation depends on Ca2+ influx via voltage-dependent Ca2+ channels in SHR aorta. Eur J Pharmacol 2005; 504:105-11. [PMID: 15507226 DOI: 10.1016/j.ejphar.2004.09.047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2004] [Revised: 09/02/2004] [Accepted: 09/14/2004] [Indexed: 11/18/2022]
Abstract
The contractile response to acidosis in isolated aorta from spontaneously hypertensive rat (SHR) depends upon tyrosine phosphorylation of phosphatidylinositol 3 kinase (PI3-kinase) and Ca2+ influx via voltage-dependent Ca2+ channels (VDCC). In this study, verapamil, a VDCC inhibitor, was shown to markedly inhibit acidic pH-induced contraction, whereas the residual contraction in the presence of verapamil was unaffected by the PI3-kinase inhibitor, 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one hydrochloride (LY-294002). Interestingly, the LY-294002-insensitive component of contraction was further inhibited by verapamil in the presence of LY-294002. Western blotting revealed that acidosis stimulated tyrosine phosphorylation of p85, which was abolished when tissues were pretreated with tyrphostin 23, a tyrosine kinase inhibitor, verapamil or EGTA. In fura-2-loaded aortic strips, acidosis induced a rise in intracellular Ca2+ ([Ca2+]i) that was partially inhibited by LY-294002. The residual increase in [Ca2+]i caused by acidosis in the presence of LY-294002 was abolished by verapamil. These findings suggest that acidosis-induced Ca2+ influx through VDCC is the upstream event leading to the tyrosine phosphorylation of PI3-kinase, which in turn contributes to the enhancement of Ca2+ entry to some extent in SHR aorta.
Collapse
Affiliation(s)
- Dileep Kumar Rohra
- Department of Pharmaceutical Molecular Biology, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba, Aramaki, Aoba-ku, Sendai 980-8578, Japan
| | | | | |
Collapse
|
25
|
Facemire CS, Arendshorst WJ. Calmodulin mediates norepinephrine-induced receptor-operated calcium entry in preglomerular resistance arteries. Am J Physiol Renal Physiol 2005; 289:F127-36. [PMID: 15701815 DOI: 10.1152/ajprenal.00397.2004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Although L-type voltage-dependent calcium channels play a major role in mediating vascular smooth muscle cell contraction in the renal vasculature, non-L-type calcium entry mechanisms represent a significant component of vasoactive agonist-induced calcium entry in these cells as well. To investigate the role of these non-voltage-dependent calcium entry pathways in the regulation of renal microvascular reactivity, we have characterized the function of store- and receptor-operated channels (SOCs and ROCs) in renal cortical interlobular arteries (ILAs) of rats. Using fura 2-loaded, microdissected ILAs, we find that the L-type channel antagonist nifedipine blocks less than half the rise in intracellular calcium concentration ([Ca(2+)](i)) elicited by norepinephrine. SOCs were activated in these vessels using the sarco/endoplasmic reticulum Ca(2+) ATPase (SERCA) inhibitors cyclopiazonic acid and thapsigargin and were dose dependently blocked by the SOC antagonists Gd(3+) and 2-aminoethoxydiphenyl borate (2-APB) and the combined SOC/ROC antagonist SKF-96365. Gd(3+) had no effect on the non-L-type Ca(2+) entry activated by 1 microM NE. A low concentration of SKF-96365 that did not affect thapsigargin-induced store-operated Ca(2+) entry blocked 60-70% of the NE-induced Ca(2+) entry. Two different calmodulin inhibitors (W-7 and trifluoperazine) also blocked the NE-induced Ca(2+) entry. These data suggest that in addition to L-type channels, NE primarily activates ROCs rather than SOCs in ILAs and that this receptor-operated Ca(2+) entry mechanism is regulated by calmodulin. Interestingly, 2-APB completely blocked the NE-induced non-L-type Ca(2+) entry, implying that SOCs and ROCs in preglomerular resistance vessels share a common molecular structure.
Collapse
Affiliation(s)
- Carie S Facemire
- Dept. of Cell and Molecular Physiology, University of North Carolina at Chapel Hill, NC 27599-7545, USA
| | | |
Collapse
|
26
|
Fellner SK, Arendshorst WJ. Angiotensin II Ca2+ signaling in rat afferent arterioles: stimulation of cyclic ADP ribose and IP3 pathways. Am J Physiol Renal Physiol 2004; 288:F785-91. [PMID: 15598842 DOI: 10.1152/ajprenal.00372.2004] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
ANG II induces a rise in cytosolic Ca(2+) ([Ca(2+)](i)) in vascular smooth muscle (VSM) cells via inositol trisphosphate receptor (IP(3)R) activation and release of Ca(2+) from the sarcoplasmic reticulum (SR). The Ca(2+) signal is augmented by calcium-induced calcium release (CICR) and by cyclic adeninediphosphate ribose (cADPR), which sensitizes the ryanodine-sensitive receptor (RyR) to Ca(2+) to further amplify CICR. cADPR is synthesized from beta-nicotinamide adenine dinucleotide (NAD(+)) by a membrane-bound bifunctional enzyme, ADPR cyclase. To investigate the possibility that ANG II activates the ADPR cyclase of afferent arterioles, we used inhibitors of the IP(3)R, RyR, and ADPR cyclase. Afferent arterioles were isolated from rat kidney with the magnetized microsphere and sieving technique and loaded with fura-2 to measure [Ca(2+)](i). In Ca(2+)-containing buffer, ANG II increased [Ca(2+)](i) by 125 +/- 10 nM. In the presence of the IP(3)R antagonists TMB-8 and 2-APB, the peak responses to ANG II were reduced by 74 and 81%, respectively. The specific antagonist of cADPR 8-Br ADPR and a high concentration of ryanodine (100 microM) inhibited the ANG II-induced increases in [Ca(2+)](i) by 75 and 69%, respectively. Nicotinamide and Zn(2+) are known inhibitors of the VSM ADPR cyclase. Nicotinamide diminished the [Ca(2+)](i) response to ANG II by 66%. In calcium-free buffer, Zn(2+) reduced the ANG II response by 68%. Simultaneous blockade of the IP(3) and cADPR pathways diminished the [Ca(2+)](i) response to ANG II by 83%. We conclude that ANG II initiates Ca(2+) mobilization from the SR in afferent arterioles via the classic IP(3)R pathway and that ANG II may lead to activation of the ADPR cyclase to form cADPR, which, via its action on the RyR, substantially augments the Ca(2+) response.
Collapse
Affiliation(s)
- Susan K Fellner
- Dept. of Cell and Molecular Physiology, Univ. of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7545, USA.
| | | |
Collapse
|
27
|
Che Q, Carmines PK. Src family kinase involvement in rat preglomerular microvascular contractile and [Ca2+]i responses to ANG II. Am J Physiol Renal Physiol 2004; 288:F658-64. [PMID: 15572518 PMCID: PMC2570959 DOI: 10.1152/ajprenal.00392.2004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Experiments were performed to investigate the potential role of Src family kinase(s) in the rat afferent arteriolar contractile response to ANG II. The in vitro blood-perfused juxtamedullary nephron technique was employed to monitor afferent arteriolar lumen diameter responses to 1-100 nM ANG II before and during Src family kinase inhibition (10 microM PP2). PP2 did not alter baseline diameter but attenuated ANG II-induced contractile responses by 33 +/- 6%. An inactive analog of PP2 (PP3) had no effect on ANG II-induced afferent arteriolar contraction. The effect of Src kinase inhibition on ANG II-induced intracellular free Ca(2+) concentration ([Ca(2+)](i)) responses was probed in fura 2-loaded preglomerular microvascular smooth muscle cells (PVSMCs) obtained from explants and studied after 3-5 days in culture. In untreated PVSMCs, ANG II evoked peak (Delta = 293 +/- 66 nM) and plateau (Delta = 23 +/- 8 nM) increases in [Ca(2+)](i). In PVSMCs pretreated with PP2, baseline [Ca(2+)](i) was unaltered, but both the peak (Delta = 140 +/- 22 nM) and plateau (Delta = 3 +/- 2 nM) phases of the ANG II response were significantly reduced compared with untreated cells. PP3 did not alter [Ca(2+)](i) responses to ANG II. Immunoprecipitation and Western blot analysis confirmed that 100 nM ANG II increased phosphorylation of c-Src (at Y(416)) in PVSMCs. The phosphorylation response was maximal 1 min after ANG II exposure and was prevented by PP2. We conclude that the preglomerular vasoconstriction evoked by ANG II involves rapid c-Src activation with subsequent effects that contribute to the [Ca(2+)](i) response to the peptide.
Collapse
Affiliation(s)
- Qi Che
- Dept. of Cellular and Integrative Physiology, Univ. of Nebraska College of Medicine, 985850 Nebraska Medical Ctr., Omaha, NE 68198-5850, USA
| | | |
Collapse
|
28
|
Salomonsson M, Arendshorst WJ. Effect of tyrosine kinase blockade on norepinephrine-induced cytosolic calcium response in rat afferent arterioles. Am J Physiol Renal Physiol 2004; 286:F866-74. [PMID: 15075182 DOI: 10.1152/ajprenal.00213.2003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We used genistein (Gen) and tyrphostin 23 (Tyr-23) to evaluate the importance of tyrosine phosphorylation in norepinephrine (NE)-induced changes in intracellular free calcium concentration ([Ca(2+)](i)) in rat afferent arterioles. [Ca(2+)](i) was measured in microdissected arterioles using ratiometric photometry of fura 2 fluorescence. The control [Ca(2+)](i) response to NE (1 microM) consisted of a rapid initial peak followed by a plateau phase sustained above baseline. Pretreatment with the tyrosine kinase inhibitor Tyr-23 (50 microM, 10 min) caused a slow 40% increase in baseline [Ca(2+)](i). Tyr-23 attenuated peak and plateau responses to NE, both by approximately 70%. In the absence of extracellular Ca(2+) (0 Ca), Tyr-23 reduced the immediate [Ca(2+)](i) response to NE by approximately 60%, indicative of mobilization of internal stores, and abolished the plateau phase. In other arterioles, the [Ca(2+)](i) response to depolarization induced by KCl (50 mM) was not attenuated by Tyr-23, indicating no direct effect on L-type Ca(+) channels activated by depolarization. The Ca(2+) channel blocker nifedipine (1 microM) inhibited the NE response by approximately 50%; the effects of nifedipine and Tyr-23 were not additive. Nifedipine had no inhibitory effect after Tyr-23 pretreatment, indicating Tyr-23 inhibition of Ca(2+) entry. Another tyrosine kinase inhibitor, Gen (5 and 50 microM), did not affect baseline [Ca(2+)](i). High-dose Gen inhibited the peak and plateau response to NE by 87 and 75%, respectively; low-dose Gen attenuated both responses by approximately 20%. In 0 Ca, Gen (50 microM) abolished the immediate [Ca(2+)](i) mobilization response. Combined nifedipine and Gen (50 microM) inhibited the rapid NE response by approximately 90% in the presence of extracellular Ca(2+). Gen (50 microM) also inhibited by 60% the [Ca(2+)](i) response to 50 mM KCl, indicating a direct interaction with voltage-sensitive, L-type Ca(2+) entry channels. These results indicate that tyrosine phosphorylation is an important link in the chain of events leading to alpha-adrenoceptor-induced Ca(2+) recruitment (both entry and release) in afferent arteriolar smooth muscle cells. Furthermore, different blockers of tyrosine kinase appear to have different modes of action in renal microvessels.
Collapse
Affiliation(s)
- Max Salomonsson
- Department of Medical Physiology, The Panum Institute, University of Copenhagen, Denmark
| | | |
Collapse
|