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Kreitzer MA, Vredeveld M, Tinner K, Powell AM, Schantz AW, Leininger R, Merillat R, Gongwer MW, Tchernookova BK, Malchow RP. ATP-mediated increase in H + efflux from retinal Müller cells of the axolotl. J Neurophysiol 2024; 131:124-136. [PMID: 38116604 DOI: 10.1152/jn.00321.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 11/17/2023] [Accepted: 12/13/2023] [Indexed: 12/21/2023] Open
Abstract
Previous work has shown that activation of tiger salamander retinal radial glial cells by extracellular ATP induces a pronounced extracellular acidification, which has been proposed to be a potent modulator of neurotransmitter release. This study demonstrates that low micromolar concentrations of extracellular ATP similarly induce significant H+ effluxes from Müller cells isolated from the axolotl retina. Müller cells were enzymatically isolated from axolotl retina and H+ fluxes were measured from individual cells using self-referencing H+-selective microelectrodes. The increased H+ efflux from axolotl Müller cells induced by extracellular ATP required activation of metabotropic purinergic receptors and was dependent upon calcium released from internal stores. We further found that the ATP-evoked increase in H+ efflux from Müller cells of both tiger salamander and axolotl were sensitive to pharmacological agents known to interrupt calmodulin and protein kinase C (PKC) activity: chlorpromazine (CLP), trifluoperazine (TFP), and W-7 (all calmodulin inhibitors) and chelerythrine, a PKC inhibitor, all attenuated ATP-elicited increases in H+ efflux. ATP-initiated H+ fluxes of axolotl Müller cells were also significantly reduced by amiloride, suggesting a significant contribution by sodium-hydrogen exchangers (NHEs). In addition, α-cyano-4-hydroxycinnamate (4-cin), a monocarboxylate transport (MCT) inhibitor, also reduced the ATP-induced increase in H+ efflux in both axolotl and tiger salamander Müller cells, and when combined with amiloride, abolished ATP-evoked increase in H+ efflux. These data suggest that axolotl Müller cells are likely to be an excellent model system to understand the cell-signaling pathways regulating H+ release from glia and the role this may play in modulating neuronal signaling.NEW & NOTEWORTHY Glial cells are a key structural part of the tripartite synapse and have been suggested to regulate synaptic transmission, but the regulatory mechanisms remain unclear. We show that extracellular ATP, a potent glial cell activator, induces H+ efflux from axolotl retinal Müller (glial) cells through a calcium-dependent pathway that is likely to involve calmodulin, PKC, Na+/H+ exchange, and monocarboxylate transport, and suggest that such H+ release may play a key role in modulating neuronal transmission.
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Affiliation(s)
- Matthew A Kreitzer
- Department of Biology, Indiana Wesleyan University, Marion, Indiana, United States
| | - Mason Vredeveld
- Department of Biology, Indiana Wesleyan University, Marion, Indiana, United States
| | - Kaleb Tinner
- Department of Biology, Indiana Wesleyan University, Marion, Indiana, United States
| | - Alyssa M Powell
- Department of Biology, Indiana Wesleyan University, Marion, Indiana, United States
| | - Adam W Schantz
- Department of Biology, Indiana Wesleyan University, Marion, Indiana, United States
| | - Rachel Leininger
- Department of Biology, Indiana Wesleyan University, Marion, Indiana, United States
| | - Rajapone Merillat
- Department of Biology, Indiana Wesleyan University, Marion, Indiana, United States
| | - Michael W Gongwer
- Department of Biology, Indiana Wesleyan University, Marion, Indiana, United States
| | - Boriana K Tchernookova
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States
| | - Robert Paul Malchow
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States
- Department of Psychology, College of the Holy Cross, Worcester, Massachusetts, United States
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2
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Shahi A, Kahle J, Hopkins C, Diakonova M. The SH2 domain and kinase activity of JAK2 target JAK2 to centrosome and regulate cell growth and centrosome amplification. PLoS One 2022; 17:e0261098. [PMID: 35089929 PMCID: PMC8797172 DOI: 10.1371/journal.pone.0261098] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 11/23/2021] [Indexed: 12/13/2022] Open
Abstract
JAK2 is cytokine-activated non-receptor tyrosine kinase. Although JAK2 is mainly localized at the plasma membrane, it is also present on the centrosome. In this study, we demonstrated that JAK2 localization to the centrosome depends on the SH2 domain and intact kinase activity. We created JAK2 mutants deficient in centrosomal localization ΔSH2, K882E and (ΔSH2, K882E). We showed that JAK2 WT clone strongly enhances cell proliferation as compared to control cells while JAK2 clones ΔSH2, K882E and (ΔSH2, K882E) proliferate slower than JAK2 WT cells. These mutant clones also progress much slower through the cell cycle as compared to JAK2 WT clone and the enhanced proliferation of JAK2 WT cells is accompanied by increased S -> G2 progression. Both the SH2 domain and the kinase activity of JAK2 play a role in prolactin-dependent activation of JAK2 substrate STAT5. We showed that JAK2 is an important regulator of centrosome function as the SH2 domain of JAK2 regulates centrosome amplification. The cells overexpressing ΔSH2 and (ΔSH2, K-E) JAK2 have almost three-fold the amplified centrosomes of WT cells. In contrast, the kinase activity of JAK2 is dispensable for centrosome amplification. Our observations provide novel insight into the role of SH2 domain and kinase activity of JAK2 in centrosome localization of JAK2 and in the regulation of cell growth and centrosome biogenesis.
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Affiliation(s)
- Aashirwad Shahi
- Department of Biological Sciences, University of Toledo, Toledo, OH, United States of America
| | - Jacob Kahle
- Department of Biological Sciences, University of Toledo, Toledo, OH, United States of America
| | - Chandler Hopkins
- Department of Biological Sciences, University of Toledo, Toledo, OH, United States of America
| | - Maria Diakonova
- Department of Biological Sciences, University of Toledo, Toledo, OH, United States of America
- * E-mail:
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3
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Qin F, Li J, Dai YF, Zhong XG, Pan YJ. Renal denervation inhibits the renin-angiotensin-aldosterone system in spontaneously hypertensive rats. Clin Exp Hypertens 2021; 44:83-92. [PMID: 34818958 DOI: 10.1080/10641963.2021.1996587] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
This study was conducted to explore the effect of renal denervation (RDN) on the renin-angiotensin-aldosterone system (RAAS) in spontaneously hypertensive rats (SHRs). Our experimental rats were randomly divided into the RDN group conducted by painting 10% phenol on the bilateral renal nerves (RDNX), the shamoperation group simply painting with saline (Sham), and the normotension control group (WKY) following all the animal blood and tissues of kidney, hypothalamus, and adrenal gland collected and examined 2 weeks after RDN operation. We found that the aldosterone (ALD) levels in serum and tissues all decreased in the RDNX group compared with the Sham group (p < .05). Meantime, the expression of angiotensin II type1 receptor (AT1R) mRNA also exhibited significantly reduced by 2.22-fold in the RDNX group compared to the Sham group identical to the expression of AT1R protein in the renal cortex and outer stripe of the outer medulla (OSOM) subjected to denervation surgery, which manifested the lower ATIR protein expression than the Sham group (p < .05). Besides, the expression of angiotensin II (Ang II) protein in the cortex , OSOM, and inner stripe of the outer medulla were all attenuated by RDN in comparison with the Sham group (p < .05). RDN reduced intrarenal RAAS and circulating RAAS to lower blood pressure and repair renal function.
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Affiliation(s)
- Fei Qin
- Department of Hypertension, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi China
| | - Jianling Li
- Department of Hypertension, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi China.,Department of Graduate School, Post-doctoral Stations of Guangxi Medical University, Nanning, Guangxi, China
| | - Yong-Fa Dai
- Department of Hypertension, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi China
| | - Xiao-Ge Zhong
- Department of Hypertension, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi China
| | - Ya-Jin Pan
- Department of Hypertension, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi China
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4
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Shakeri H, Boen JRA, De Moudt S, Hendrickx JO, Leloup AJA, Jacobs G, De Meyer GRY, De Keulenaer GW, Guns PJDF, Segers VFM. Neuregulin-1 compensates for endothelial nitric oxide synthase deficiency. Am J Physiol Heart Circ Physiol 2021; 320:H2416-H2428. [PMID: 33989083 DOI: 10.1152/ajpheart.00914.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Endothelial cells (ECs) secrete different paracrine signals that modulate the function of adjacent cells; two examples of these paracrine signals are nitric oxide (NO) and neuregulin-1 (NRG1), a cardioprotective growth factor. Currently, it is undetermined whether one paracrine factor can compensate for the loss of another. Herein, we hypothesized that NRG1 can compensate for endothelial NO synthase (eNOS) deficiency. We characterized eNOS null and wild-type (WT) mice by cardiac ultrasound and histology and we determined circulating NRG1 levels. In a separate experiment, eight groups of mice were divided into four groups of eNOS null mice and WT mice; half of the mice received angiotensin II (ANG II) to induce a more severe phenotype. Mice were randomized to daily injections with NRG1 or vehicle for 28 days. eNOS deficiency increased NRG1 plasma levels, indicating that ECs increase their NRG1 expression when NO production is deleted. eNOS deficiency also increased blood pressure, lowered heart rate, induced cardiac fibrosis, and affected diastolic function. In eNOS null mice, ANG II administration not only increased cardiac fibrosis but also induced cardiac hypertrophy and renal fibrosis. NRG1 administration prevented cardiac and renal hypertrophy and fibrosis caused by ANG II infusion and eNOS deficiency. Moreover, Nrg1 expression in the myocardium is shown to be regulated by miR-134. This study indicates that administration of endothelium-derived NRG1 can compensate for eNOS deficiency in the heart and kidneys.NEW & NOTEWORTHY ECs compensate for eNOS deficiency by increasing the secretion of NRG1. NRG1 administration prevents cardiac and renal hypertrophy and fibrosis caused by ANG II infusion and eNOS deficiency. NRG1 expression is regulated by miR-134.
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Affiliation(s)
- Hadis Shakeri
- Laboratory of Physiopharmacology, University of Antwerp, Antwerp, Belgium
| | - Jente R A Boen
- Laboratory of Physiopharmacology, University of Antwerp, Antwerp, Belgium.,Research Group Cardiovascular Diseases, GENCOR Department, University of Antwerp, Antwerp, Belgium
| | - Sofie De Moudt
- Laboratory of Physiopharmacology, University of Antwerp, Antwerp, Belgium
| | - Jhana O Hendrickx
- Laboratory of Physiopharmacology, University of Antwerp, Antwerp, Belgium
| | - Arthur J A Leloup
- Laboratory of Physiopharmacology, University of Antwerp, Antwerp, Belgium
| | - Griet Jacobs
- Laboratory of Physiopharmacology, University of Antwerp, Antwerp, Belgium
| | - Guido R Y De Meyer
- Laboratory of Physiopharmacology, University of Antwerp, Antwerp, Belgium
| | - Gilles W De Keulenaer
- Laboratory of Physiopharmacology, University of Antwerp, Antwerp, Belgium.,Hartcentrum ZNA, Antwerp, Belgium
| | | | - Vincent F M Segers
- Laboratory of Physiopharmacology, University of Antwerp, Antwerp, Belgium.,Department of Cardiology, University Hospital Antwerp, Edegem, Belgium
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5
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Sjøgaard-Frich LM, Prestel A, Pedersen ES, Severin M, Kristensen KK, Olsen JG, Kragelund BB, Pedersen SF. Dynamic Na +/H + exchanger 1 (NHE1) - calmodulin complexes of varying stoichiometry and structure regulate Ca 2+-dependent NHE1 activation. eLife 2021; 10:60889. [PMID: 33655882 PMCID: PMC8009664 DOI: 10.7554/elife.60889] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 03/01/2021] [Indexed: 11/25/2022] Open
Abstract
Calmodulin (CaM) engages in Ca2+-dependent interactions with numerous proteins, including a still incompletely understood physical and functional interaction with the human Na+/H+-exchanger NHE1. Using nuclear magnetic resonance (NMR) spectroscopy, isothermal titration calorimetry, and fibroblasts stably expressing wildtype and mutant NHE1, we discovered multiple accessible states of this functionally important complex existing in different NHE1:CaM stoichiometries and structures. We determined the NMR solution structure of a ternary complex in which CaM links two NHE1 cytosolic tails. In vitro, stoichiometries and affinities could be tuned by variations in NHE1:CaM ratio and calcium ([Ca2+]) and by phosphorylation of S648 in the first CaM-binding α-helix. In cells, Ca2+-CaM-induced NHE1 activity was reduced by mimicking S648 phosphorylation and by mutation of the first CaM-binding α-helix, whereas it was unaffected by inhibition of Akt, one of several kinases phosphorylating S648. Our results demonstrate a diversity of NHE1:CaM interaction modes and suggest that CaM may contribute to NHE1 dimerization and thereby augment NHE1 regulation. We propose that a similar structural diversity is of relevance to many other CaM complexes.
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Affiliation(s)
- Lise M Sjøgaard-Frich
- Section for Cell Biology and Physiology, Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Andreas Prestel
- Structural Biology and NMR Laboratory, Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Emilie S Pedersen
- Structural Biology and NMR Laboratory, Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Marc Severin
- Section for Cell Biology and Physiology, Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Kristian Kølby Kristensen
- Finsen Laboratory, Rigshospitalet, Copenhagen, Denmark.,Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
| | - Johan G Olsen
- Structural Biology and NMR Laboratory, Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Birthe B Kragelund
- Structural Biology and NMR Laboratory, Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Stine Falsig Pedersen
- Section for Cell Biology and Physiology, Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
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6
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Escudero DS, Pérez NG, Díaz RG. Myocardial Impact of NHE1 Regulation by Sildenafil. Front Cardiovasc Med 2021; 8:617519. [PMID: 33693035 PMCID: PMC7937606 DOI: 10.3389/fcvm.2021.617519] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 01/04/2021] [Indexed: 11/13/2022] Open
Abstract
The cardiac Na+/H+ exchanger (NHE1) is a membrane glycoprotein fundamental for proper cell functioning due its multiple housekeeping tasks, including regulation of intracellular pH, Na+ concentration, and cell volume. In the heart, hyperactivation of NHE1 has been linked to the development of different pathologies. Several studies in animal models that reproduce the deleterious effects of ischemia/reperfusion injury or cardiac hypertrophy have conclusively demonstrated that NHE1 inhibition provides cardioprotection. Unfortunately, NHE1 inhibitors failed to reproduce these effects in the clinical arena. The reasons for those discrepancies are not apparent yet. However, a reasonable clue to consider would be that drugs that completely abolish the exchanger activity, including that its essential housekeeping function may not be the best therapeutic approach. Therefore, interventions tending to specifically reduce its hyperactive state without affecting its basal activity emerge as a novel potential gold standard. In this regard, a promising goal seems to be the modulation of the phosphorylation state of the cytosolic tail of the exchanger. Recent own experiments demonstrated that Sildenafil, a phosphodiesterase 5A inhibitor drug that has been widely used for the treatment of erectile dysfunction is able to decrease NHE1 phosphorylation, and hence reduce its hyperactivity. In connection, growing evidence demonstrates cardioprotective properties of Sildenafil against different cardiac pathologies, with the distinctive characteristic of directly affecting cardiac tissue without altering blood pressure. This mini-review was aimed to focus on the regulation of NHE1 activity by Sildenafil. For this purpose, experimental data reporting Sildenafil effects in different animal models of heart disease will be discussed.
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Affiliation(s)
- Daiana S Escudero
- Centro de Investigaciones Cardiovasculares "Dr. Horacio E. Cingolani", Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Néstor G Pérez
- Centro de Investigaciones Cardiovasculares "Dr. Horacio E. Cingolani", Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Romina G Díaz
- Centro de Investigaciones Cardiovasculares "Dr. Horacio E. Cingolani", Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
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7
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Massip-Copiz MM, Valdivieso ÁG, Clauzure M, Mori C, Asensio CJA, Aguilar MÁ, Santa-Coloma TA. Epidermal growth factor receptor activity upregulates lactate dehydrogenase A expression, lactate dehydrogenase activity, and lactate secretion in cultured IB3-1 cystic fibrosis lung epithelial cells. Biochem Cell Biol 2021; 99:476-487. [PMID: 33481676 DOI: 10.1139/bcb-2020-0522] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Cystic fibrosis (CF) is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. It has been postulated that reduced HCO3- transport through CFTR may lead to a decreased airway surface liquid pH. In contrast, others have reported no changes in the extracellular pH (pHe). We have recently reported that in carcinoma Caco-2/pRS26 cells (transfected with short hairpin RNA for CFTR) or CF lung epithelial IB3-1 cells, the mutation in CFTR decreased mitochondrial complex I activity and increased lactic acid production, owing to an autocrine IL-1β loop. The secreted lactate accounted for the reduced pHe, because oxamate fully restored the pHe. These effects were attributed to the IL-1β autocrine loop and the downstream signaling kinases c-Src and JNK. Here we show that the pHe of IB3-1 cells can be restored to normal values (∼7.4) by incubation with the epidermal growth factor receptor (EGFR, HER1, ErbB1) inhibitors AG1478 and PD168393. PD168393 fully restored the pHe values of IB3-1 cells, suggesting that the reduced pHe is mainly due to increased EGFR activity and lactate. Also, in IB3-1 cells, lactate dehydrogenase A mRNA, protein expression, and activity are downregulated when EGFR is inhibited. Thus, a constitutive EGFR activation seems to be responsible for the reduced pHe in IB3-1 cells.
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Affiliation(s)
- María Macarena Massip-Copiz
- Laboratory of Cellular and Molecular Biology, Institute for Biomedical Research, School of Medical Sciences, Pontifical Catholic University of Argentina, and the Pontifical Catholic University of Argentina, Buenos Aires, Argentina.,Laboratory of Cellular and Molecular Biology, Institute for Biomedical Research, School of Medical Sciences, Pontifical Catholic University of Argentina, and the Pontifical Catholic University of Argentina, Buenos Aires, Argentina
| | - Ángel G Valdivieso
- Laboratory of Cellular and Molecular Biology, Institute for Biomedical Research, School of Medical Sciences, Pontifical Catholic University of Argentina, and the Pontifical Catholic University of Argentina, Buenos Aires, Argentina.,Laboratory of Cellular and Molecular Biology, Institute for Biomedical Research, School of Medical Sciences, Pontifical Catholic University of Argentina, and the Pontifical Catholic University of Argentina, Buenos Aires, Argentina
| | - Mariángeles Clauzure
- Laboratory of Cellular and Molecular Biology, Institute for Biomedical Research, School of Medical Sciences, Pontifical Catholic University of Argentina, and the Pontifical Catholic University of Argentina, Buenos Aires, Argentina.,Laboratory of Cellular and Molecular Biology, Institute for Biomedical Research, School of Medical Sciences, Pontifical Catholic University of Argentina, and the Pontifical Catholic University of Argentina, Buenos Aires, Argentina
| | - Consuelo Mori
- Laboratory of Cellular and Molecular Biology, Institute for Biomedical Research, School of Medical Sciences, Pontifical Catholic University of Argentina, and the Pontifical Catholic University of Argentina, Buenos Aires, Argentina.,Laboratory of Cellular and Molecular Biology, Institute for Biomedical Research, School of Medical Sciences, Pontifical Catholic University of Argentina, and the Pontifical Catholic University of Argentina, Buenos Aires, Argentina
| | - Cristian J A Asensio
- Laboratory of Cellular and Molecular Biology, Institute for Biomedical Research, School of Medical Sciences, Pontifical Catholic University of Argentina, and the Pontifical Catholic University of Argentina, Buenos Aires, Argentina.,Laboratory of Cellular and Molecular Biology, Institute for Biomedical Research, School of Medical Sciences, Pontifical Catholic University of Argentina, and the Pontifical Catholic University of Argentina, Buenos Aires, Argentina
| | - María Á Aguilar
- Laboratory of Cellular and Molecular Biology, Institute for Biomedical Research, School of Medical Sciences, Pontifical Catholic University of Argentina, and the Pontifical Catholic University of Argentina, Buenos Aires, Argentina.,Laboratory of Cellular and Molecular Biology, Institute for Biomedical Research, School of Medical Sciences, Pontifical Catholic University of Argentina, and the Pontifical Catholic University of Argentina, Buenos Aires, Argentina
| | - Tomás A Santa-Coloma
- Laboratory of Cellular and Molecular Biology, Institute for Biomedical Research, School of Medical Sciences, Pontifical Catholic University of Argentina, and the Pontifical Catholic University of Argentina, Buenos Aires, Argentina.,Laboratory of Cellular and Molecular Biology, Institute for Biomedical Research, School of Medical Sciences, Pontifical Catholic University of Argentina, and the Pontifical Catholic University of Argentina, Buenos Aires, Argentina
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8
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The multifunctional role of phospho-calmodulin in pathophysiological processes. Biochem J 2018; 475:4011-4023. [PMID: 30578290 PMCID: PMC6305829 DOI: 10.1042/bcj20180755] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 11/23/2018] [Accepted: 11/30/2018] [Indexed: 02/06/2023]
Abstract
Calmodulin (CaM) is a versatile Ca2+-sensor/transducer protein that modulates hundreds of enzymes, channels, transport systems, transcription factors, adaptors and other structural proteins, controlling in this manner multiple cellular functions. In addition to its capacity to regulate target proteins in a Ca2+-dependent and Ca2+-independent manner, the posttranslational phosphorylation of CaM by diverse Ser/Thr- and Tyr-protein kinases has been recognized as an important additional manner to regulate this protein by fine-tuning its functionality. In this review, we shall cover developments done in recent years in which phospho-CaM has been implicated in signalling pathways that are relevant for the onset and progression of diverse pathophysiological processes. These include diverse systems playing a major role in carcinogenesis and tumour development, prion-induced encephalopathies and brain hypoxia, melatonin-regulated neuroendocrine disorders, hypertension, and heavy metal-induced cell toxicity.
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9
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Jensen HH, Pedersen GA, Morgen JJ, Parsons M, Pedersen SF, Nejsum LN. The Na + /H + exchanger NHE1 localizes as clusters to cryptic lamellipodia and accelerates collective epithelial cell migration. J Physiol 2018; 597:849-867. [PMID: 30471113 DOI: 10.1113/jp277383] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 11/16/2018] [Indexed: 12/12/2022] Open
Abstract
KEY POINTS Exogenous Na+ /H+ exchanger 1 (NHE1) expression stimulated the collective migration of epithelial cell sheets Stimulation with epidermal growth factor, a key morphogen, primarily increased migration of the front row of cells, whereas NHE1 increased that of submarginal cell rows, and the two stimuli were additive Accordingly, NHE1 localized not only to the leading edges of leader cells, but also in cryptic lamellipodia in submarginal cell rows NHE1 expression disrupted the morphology of epithelial cell sheets and three-dimensional cysts ABSTRACT: Collective cell migration plays essential roles in embryonic development, in normal epithelial repair processes, and in many diseases including cancer. The Na+ /H+ exchanger 1 (NHE1, SLC9A1) is an important regulator of motility in many cells and has been widely studied for its roles in cancer, although its possible role in collective migration of normal epithelial cells has remained unresolved. In the present study, we show that NHE1 expression in MDCK-II kidney epithelial cells accelerated collective cell migration. NHE1 localized to the leading edges of leader cells, as well as to cryptic lamellipodia in submarginal cell rows. Epidermal growth factor, a kidney morphogen, increased displacement of the front row of collectively migrating cells and reduced the number of migration fingers. NHE1 expression increased the number of migration fingers and increased displacement of submarginal cell rows, resulting in additive effects of NHE1 and epidermal growth factor. Finally, NHE1 expression resulted in disorganized development of MDCK-II cell cysts. Thus, NHE1 contributes to collective migration and epithelial morphogenesis, suggesting roles for the transporter in embryonic and early postnatal development.
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Affiliation(s)
- Helene H Jensen
- Department of Clinical Medicine, Aarhus University, Denmark.,Department of Molecular Biology and Genetics, Aarhus University, Denmark.,Department of Chemistry and Bioscience, Aalborg University, Denmark
| | | | - Jeanette J Morgen
- Department of Clinical Medicine, Aarhus University, Denmark.,Department of Molecular Biology and Genetics, Aarhus University, Denmark
| | - Maddy Parsons
- Randall Division of Cell and Molecular Biophysics, King's College London, UK
| | - Stine F Pedersen
- Department of Biology, Section for Cell Biology and Physiology, University of Copenhagen, Denmark
| | - Lene N Nejsum
- Department of Clinical Medicine, Aarhus University, Denmark
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10
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Cardoso VG, Gonçalves GL, Costa-Pessoa JM, Thieme K, Lins BB, Casare FAM, de Ponte MC, Camara NOS, Oliveira-Souza M. Angiotensin II-induced podocyte apoptosis is mediated by endoplasmic reticulum stress/PKC-δ/p38 MAPK pathway activation and trough increased Na +/H + exchanger isoform 1 activity. BMC Nephrol 2018; 19:179. [PMID: 30005635 PMCID: PMC6043975 DOI: 10.1186/s12882-018-0968-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 06/26/2018] [Indexed: 11/12/2022] Open
Abstract
Background Angiotensin II (Ang II) contributes to the progression of renal diseases associated with proteinuria and glomerulosclerosis mainly by inducing podocyte apoptosis. In the present study, we investigated whether the chronic effects of Ang II via AT1 receptor (AT1R) would result in endoplasmic reticulum (ER) stress/PKC-delta/p38 MAPK stimulation, and consequently podocyte apoptosis. Methods Wistar rats were treated with Ang II (200 ng·kg−1·min−1, 42 days) and or losartan (10 mg·kg−1·day−1, 14 days). Immortalized mouse podocyte were treated with 1 μM Ang II and/or losartan (1 μM) or SB203580 (0.1 μM) (AT1 receptor antagonist and p38 MAPK inhibitor) for 24 h. Kidney sections and cultured podocytes were used to evaluate protein expression by immunofluorescence and immunoblotting. Apoptosis was evaluated by flow cytometry and intracellular pH (pHi) was analyzed using microscopy combined with the fluorescent probe BCECF/AM. Results Compared with controls, Ang II via AT1R increased chaperone GRP 78/Bip protein expression in rat glomeruli (p < 0.001) as well as in podocyte culture (p < 0.01); increased phosphorylated eIf2-α (p < 0.05), PKC-delta (p < 0.01) and p38 MAPK (p < 0.001) protein expression. Furthermore, Ang II induced p38 MAPK-mediated late apoptosis and increased the Bax/Bcl-2 ratio (p < 0.001). Simultaneously, Ang II via AT1R induced p38 MAPK-NHE1-mediated increase of pHi recovery rate after acid loading. Conclusion Together, our results indicate that Ang II-induced podocyte apoptosis is associated with AT1R/ER stress/PKC-delta/p38 MAPK axis and enhanced NHE1-mediated pHi recovery rate.
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Affiliation(s)
- Vanessa Gerolde Cardoso
- Laboratory of Renal Physiology, Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, SP, 05508-900, Brazil
| | - Guilherme Lopes Gonçalves
- Laboratory of Renal Physiology, Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, SP, 05508-900, Brazil
| | - Juliana Martins Costa-Pessoa
- Laboratory of Renal Physiology, Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, SP, 05508-900, Brazil
| | - Karina Thieme
- Laboratory of Carbohydrates and Radioimmunoassays (LIM-18), Medical School, University of Sao Paulo, Sao Paulo, Brazil
| | - Bruna Bezerra Lins
- Laboratory of Renal Physiology, Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, SP, 05508-900, Brazil
| | - Fernando Augusto Malavazzi Casare
- Laboratory of Renal Physiology, Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, SP, 05508-900, Brazil
| | - Mariana Charleaux de Ponte
- Laboratory of Renal Physiology, Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, SP, 05508-900, Brazil
| | - Niels Olsen Saraiva Camara
- Laboratory for Transplantation Immunobiology, Department of Immunology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Maria Oliveira-Souza
- Laboratory of Renal Physiology, Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, SP, 05508-900, Brazil.
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11
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Dykes SS, Steffan JJ, Cardelli JA. Lysosome trafficking is necessary for EGF-driven invasion and is regulated by p38 MAPK and Na+/H+ exchangers. BMC Cancer 2017; 17:672. [PMID: 28978320 PMCID: PMC5628462 DOI: 10.1186/s12885-017-3660-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 09/27/2017] [Indexed: 12/27/2022] Open
Abstract
Background Tumor invasion through a basement membrane is one of the earliest steps in metastasis, and growth factors, such as Epidermal Growth Factor (EGF) and Hepatocyte Growth Factor (HGF), stimulate this process in a majority of solid tumors. Basement membrane breakdown is one of the hallmarks of invasion; therefore, tumor cells secrete a variety of proteases to aid in this process, including lysosomal proteases. Previous studies demonstrated that peripheral lysosome distribution coincides with the release of lysosomal cathepsins. Methods Immunofluorescence microscopy, western blot, and 2D and 3D cell culture techniques were performed to evaluate the effects of EGF on lysosome trafficking and cell motility and invasion. Results EGF-mediated lysosome trafficking, protease secretion, and invasion is regulated by the activity of p38 mitogen activated protein kinase (MAPK) and sodium hydrogen exchangers (NHEs). Interestingly, EGF stimulates anterograde lysosome trafficking through a different mechanism than previously reported for HGF, suggesting that there are redundant signaling pathways that control lysosome positioning and trafficking in tumor cells. Conclusions These data suggest that EGF stimulation induces peripheral (anterograde) lysosome trafficking, which is critical for EGF-mediated invasion and protease release, through the activation of p38 MAPK and NHEs. Taken together, this report demonstrates that anterograde lysosome trafficking is necessary for EGF-mediated tumor invasion and begins to characterize the molecular mechanisms required for EGF-stimulated lysosome trafficking. Electronic supplementary material The online version of this article (10.1186/s12885-017-3660-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Samantha S Dykes
- Department of Microbiology and Immunology, Louisiana State University Health Sciences Center - Shreveport, Shreveport, LA, 71130, USA.,Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center- Shreveport, Shreveport, LA, 71130, USA.,Present Address: Department of Radiation Oncology, University of Florida, Gainesville, FL, 32608, USA
| | - Joshua J Steffan
- Department of Natural Sciences, Dickinson State University, 291 Campus Dr, Dickinson, ND, 58601, USA.
| | - James A Cardelli
- Department of Microbiology and Immunology, Louisiana State University Health Sciences Center - Shreveport, Shreveport, LA, 71130, USA.,Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center- Shreveport, Shreveport, LA, 71130, USA
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12
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Sunitha MM, Srikanth L, Kumar PS, Chandrasekhar C, Sarma PVGK. Down-regulation of PAX2 promotes in vitro differentiation of podocytes from human CD34+ cells. Cell Tissue Res 2017; 370:477-488. [DOI: 10.1007/s00441-017-2680-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 08/07/2017] [Indexed: 12/16/2022]
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13
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Lee HW, Khan SQ, Khaliqdina S, Altintas MM, Grahammer F, Zhao JL, Koh KH, Tardi NJ, Faridi MH, Geraghty T, Cimbaluk DJ, Susztak K, Moita LF, Baltimore D, Tharaux PL, Huber TB, Kretzler M, Bitzer M, Reiser J, Gupta V. Absence of miR-146a in Podocytes Increases Risk of Diabetic Glomerulopathy via Up-regulation of ErbB4 and Notch-1. J Biol Chem 2016; 292:732-747. [PMID: 27913625 DOI: 10.1074/jbc.m116.753822] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Revised: 12/01/2016] [Indexed: 12/31/2022] Open
Abstract
Podocyte injury is an early event in diabetic kidney disease and is a hallmark of glomerulopathy. MicroRNA-146a (miR-146a) is highly expressed in many cell types under homeostatic conditions, and plays an important anti-inflammatory role in myeloid cells. However, its role in podocytes is unclear. Here, we show that miR-146a expression levels decrease in the glomeruli of patients with type 2 diabetes (T2D), which correlates with increased albuminuria and glomerular damage. miR-146a levels are also significantly reduced in the glomeruli of albuminuric BTBR ob/ob mice, indicating its significant role in maintaining podocyte health. miR-146a-deficient mice (miR-146a-/-) showed accelerated development of glomerulopathy and albuminuria upon streptozotocin (STZ)-induced hyperglycemia. The miR-146a targets, Notch-1 and ErbB4, were also significantly up-regulated in the glomeruli of diabetic patients and mice, suggesting induction of the downstream TGFβ signaling. Treatment with a pan-ErbB kinase inhibitor erlotinib with nanomolar activity against ErbB4 significantly suppressed diabetic glomerular injury and albuminuria in both WT and miR-146a-/- animals. Treatment of podocytes in vitro with TGF-β1 resulted in increased expression of Notch-1, ErbB4, pErbB4, and pEGFR, the heterodimerization partner of ErbB4, suggesting increased ErbB4/EGFR signaling. TGF-β1 also increased levels of inflammatory cytokine monocyte chemoattractant protein-1 (MCP-1) and MCP-1 induced protein-1 (MCPIP1), a suppressor of miR-146a, suggesting an autocrine loop. Inhibition of ErbB4/EGFR with erlotinib co-treatment of podocytes suppressed this signaling. Our findings suggest a novel role for miR-146a in protecting against diabetic glomerulopathy and podocyte injury. They also point to ErbB4/EGFR as a novel, druggable target for therapeutic intervention, especially because several pan-ErbB inhibitors are clinically available.
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Affiliation(s)
- Ha Won Lee
- From the Departments of Internal Medicine and
| | | | | | | | - Florian Grahammer
- the Department of Medicine IV, Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Jimmy L Zhao
- the Department of Medicine, New York Presbyterian/Weill Cornell Medical Center, New York, New York 10065.,the Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125
| | - Kwi Hye Koh
- From the Departments of Internal Medicine and
| | | | | | | | - David J Cimbaluk
- Pathology, Rush University Medical Center, Chicago, Illinois 60612
| | - Katalin Susztak
- the Department of Medicine, Renal Electrolyte and Hypertension Division, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Luis F Moita
- the Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, 2780-156 Oeiras, Portugal
| | - David Baltimore
- the Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125
| | - Pierre-Louis Tharaux
- the Paris Cardiovascular Centre (PARCC), Institut National de la Santé et de la Recherche Médicale (INSERM), 75015 Paris, France and the Université Paris Descartes, Sorbonne Paris Cité, 75270 Paris, France
| | - Tobias B Huber
- the Department of Medicine IV, Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany.,the BIOSS Center for Biological Signalling Studies, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany.,the FRIAS, Freiburg Institute for Advanced Studies and ZBSA-Center for Systems Biology, Albert-Ludwigs-University, 79104 Freiburg, Germany, and
| | - Matthias Kretzler
- the Division of Nephrology, University of Michigan, Ann Arbor, Michigan 48109
| | - Markus Bitzer
- the Division of Nephrology, University of Michigan, Ann Arbor, Michigan 48109
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14
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Abstract
As a new antitumor drug, simotinib hydrochloride is prescribed for prolonged periods, often to patients with comorbidities. Therefore, the risk for developing drug resistance and drug-drug interactions between simotinib and other agents has to be taken into consideration. As P-glycoprotein (P-gp) is an efflux transporter, which plays a significant role in drug resistance and influences the pharmacological properties and toxicities of the drugs it interacts with, the interactions between simotinib and P-gp were investigated. Cytotoxicity was measured using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. Intracellular drug concentrations were detected by high-performance liquid chromatography, fluorescence-activated cell sorting and using a fluorescence reader. P-gp ATPase activity was measured using the Pgp-Glo assay, and intracellular pH was assessed using the fluorescent probe 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein acetoxymethyl. The expression and transcription of P-gp were detected by western blotting and the luciferase assay. Simotinib has no cross-resistance to P-gp substrates, and its efflux rate was independent of either the P-gp expression or the coadministered P-gp substrate. Simotinib reversed chemotherapeutic agent resistance in a short time by increasing the intracellular concentration of the chemotherapeutic agent and blocked rhodamine 123 efflux. Further studies demonstrated that simotinib inhibited P-gp activity by modulating its ATPase activity and the intracellular pH. Although simotinib induced P-gp expression after extended treatment, the induced expression of P-gp had little impact on drug resistance. Simotinib is not a substrate of P-gp. As a modulator, it functions mainly as an inhibitor of P-gp by modulating the intracellular pH and ATPase activity, although it also induces P-gp expression after extended treatment.
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15
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The activating role of phospho-(Tyr)-calmodulin on the epidermal growth factor receptor. Biochem J 2015; 472:195-204. [DOI: 10.1042/bj20150851] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 09/22/2015] [Indexed: 02/06/2023]
Abstract
The existence of a calmodulin (CaM)/phospho-(Tyr)-CaM cycle involved in the regulation of the epidermal growth factor receptor could have important consequences for the control of cell proliferation, as its alteration could potentially result in uncontrolled tumour growth.
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16
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Wada Y, Iyoda M, Matsumoto K, Shindo-Hirai Y, Kuno Y, Yamamoto Y, Suzuki T, Saito T, Iseri K, Shibata T. Epidermal growth factor receptor inhibition with erlotinib partially prevents cisplatin-induced nephrotoxicity in rats. PLoS One 2014; 9:e111728. [PMID: 25390346 PMCID: PMC4229108 DOI: 10.1371/journal.pone.0111728] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2014] [Accepted: 10/05/2014] [Indexed: 11/19/2022] Open
Abstract
The effects of blocking the epidermal growth factor receptor (EGFR) in acute kidney injury (AKI) are controversial. Here we investigated the renoprotective effect of erlotinib, a selective tyrosine kinase inhibitor that can block EGFR activity, on cisplatin (CP)-induced AKI. Groups of animals were given either erlotinib or vehicle from one day before up to Day 3 following induction of CP-nephrotoxicity (CP-N). In addition, we analyzed the effects of erlotinib on signaling pathways involved in CP-N by using human renal proximal tubular cells (HK-2). Compared to controls, rats treated with erlotinib exhibited significant improvement of renal function and attenuation of tubulointerstitial injury, and reduced the number of apoptotic and proliferating cells. Erlotinib-treated rats had a significant reduction of renal cortical mRNA for profibrogenic genes. The Bax/Bcl-2 mRNA and protein ratios were significantly reduced by erlotinib treatment. In vitro, we observed that erlotinib significantly reduced the phosphorylation of MEK1 and Akt, processes that were induced by CP in HK-2. Taken together, these data indicate that erlotinib has renoprotective properties that are likely mediated through decreases in the apoptosis and proliferation of tubular cells, effects that reflect inhibition of downstream signaling pathways of EGFR. These results suggest that erlotinib may be useful for preventing AKI in patients receiving CP chemotherapy.
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Affiliation(s)
- Yukihiro Wada
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Masayuki Iyoda
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
- * E-mail:
| | - Kei Matsumoto
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Yuki Shindo-Hirai
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Yoshihiro Kuno
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Yasutaka Yamamoto
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Taihei Suzuki
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Tomohiro Saito
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Ken Iseri
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Takanori Shibata
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
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17
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Chen J, Chen JK, Harris RC. EGF receptor deletion in podocytes attenuates diabetic nephropathy. J Am Soc Nephrol 2014; 26:1115-25. [PMID: 25185988 DOI: 10.1681/asn.2014020192] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 07/30/2014] [Indexed: 11/03/2022] Open
Abstract
The generation of reactive oxygen species (ROS), particularly superoxide, by damaged or dysfunctional mitochondria has been postulated to be an initiating event in the development of diabetes complications. The glomerulus is a primary site of diabetic injury, and podocyte injury is a classic hallmark of diabetic glomerular lesions. In streptozotocin-induced type 1 diabetes, podocyte-specific EGF receptor (EGFR) knockout mice (EGFR(podKO)) and their wild-type (WT) littermates had similar levels of hyperglycemia and polyuria, but EGFR(podKO) mice had significantly less albuminuria and less podocyte loss compared with WT diabetic mice. Furthermore, EGFR(podKO) diabetic mice had less TGF-β1 expression, Smad2/3 phosphorylation, and glomerular fibronectin deposition. Immunoblotting of isolated glomerular lysates revealed that the upregulation of cleaved caspase 3 and downregulation of Bcl2 in WT diabetic mice were attenuated in EGFR(podKO) diabetic mice. Administration of the SOD mimetic mito-tempol or the NADPH oxidase inhibitor apocynin attenuated the upregulation of p-c-Src, p-EGFR, p-ERK1/2, p-Smad2/3, and TGF-β1 expression and prevented the alteration of cleaved caspase 3 and Bcl2 expression in glomeruli of WT diabetic mice. High-glucose treatment of cultured mouse podocytes induced similar alterations in the production of ROS; phosphorylation of c-Src, EGFR, and Smad2/3; and expression of TGF-β1, cleaved caspase 3, and Bcl2. These alterations were inhibited by treatment with mito-tempol or apocynin or by inhibiting EGFR expression or activity. Thus, results of our studies utilizing mice with podocyte-specific EGFR deletion demonstrate that EGFR activation has a major role in activating pathways that mediate podocyte injury and loss in diabetic nephropathy.
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Affiliation(s)
- Jianchun Chen
- Department of Veterans Affairs, Nashville, Tennessee; Departments of Medicine and
| | - Jian-Kang Chen
- Departments of Cellular Biology and Anatomy and Medicine, Medical College of Georgia, Georgia Regents University, Augusta, Georgia
| | - Raymond C Harris
- Department of Veterans Affairs, Nashville, Tennessee; Departments of Medicine and Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee; and
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18
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Coaxum SD, Blanton MG, Joyner A, Akter T, Bell PD, Luttrell LM, Raymond JR, Lee MH, Blichmann PA, Garnovskaya MN, Saigusa T. Epidermal growth factor-induced proliferation of collecting duct cells from Oak Ridge polycystic kidney mice involves activation of Na+/H+ exchanger. Am J Physiol Cell Physiol 2014; 307:C554-60. [PMID: 25055824 DOI: 10.1152/ajpcell.00188.2014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Epidermal growth factor (EGF) is linked to the pathogenesis of polycystic kidney disease (PKD). We explored signaling pathways activated by EGF in orpk cilia (-) collecting duct cell line derived from a mouse model of PKD (hypomorph of the Tg737/Ift88 gene) with severely stunted cilia, and in a control orpk cilia (+) cell line with normal cilia. RT-PCR demonstrated mRNAs for EGF receptor subunits ErbB1, ErbB2, ErbB3, ErbB4, and mRNAs for Na(+)/H(+) exchangers (NHE), NHE-1, NHE-2, NHE-3, NHE-4, and NHE-5 in both cell lines. EGF stimulated proton efflux in both cell lines. This effect was significantly attenuated by MIA, 5-(n-methyl-N-isobutyl) amiloride, a selective inhibitor of NHE-1 and NHE-2, and orpk cilia (-) cells were more sensitive to MIA than control cells (P < 0.01). EGF significantly induced extracellular signal-regulated kinase (ERK) phosphorylation in both cilia (+) and cilia (-) cells (63.3 and 123.6%, respectively), but the effect was more pronounced in orpk cilia (-) cells (P < 0.01). MIA significantly attenuated EGF-induced ERK phosphorylation only in orpk cilia (-) cells (P < 0.01). EGF increased proliferation of orpk cilia (+) cells and orpk cilia (-) cells, respectively, and MIA at 1-5 μM attenuated EGF-induced proliferation in orpk cilia (-) cells without affecting proliferation of orpk cilia (+) cells. EGF-induced proliferation of both cell lines was significantly decreased by the EGFR tyrosine kinase inhibitor AG1478 and MEK inhibitor PD98059. These results suggest that EGF exerts mitogenic effects in the orpk cilia (-) cells via activation of growth-associated amiloride-sensitive NHEs and ERK.
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Affiliation(s)
- Sonya D Coaxum
- Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, South Carolina
| | - Mary G Blanton
- Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, South Carolina
| | - Alisha Joyner
- College of Medicine, Medical University of South Carolina, Charleston, South Carolina
| | - Tanjina Akter
- Department of Medicine, Division of Rheumatology and Immunology, Medical University of South Carolina, Charleston, South Carolina
| | - P Darwin Bell
- Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, South Carolina; Medical and Research Services of the Ralph H. Johnson VAMC, Charleston, Carolina
| | - Louis M Luttrell
- Department of Medicine, Division of Endocrinology, Medical University of South Carolina, Charleston, South Carolina; and
| | - John R Raymond
- Department of Medicine, Division of Nephrology, Medical College of Wisconsin and the Medical Service of the Clement J. Zablocki VA Medical Center, Milwaukee, Wisconsin
| | - Mi-Hye Lee
- Department of Medicine, Division of Endocrinology, Medical University of South Carolina, Charleston, South Carolina; and
| | - Paul A Blichmann
- Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, South Carolina
| | - Maria N Garnovskaya
- Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, South Carolina
| | - Takamitsu Saigusa
- Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, South Carolina;
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19
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Liu Q, Wu C, Cai H, Hu N, Zhou J, Wang P. Cell-based biosensors and their application in biomedicine. Chem Rev 2014; 114:6423-61. [PMID: 24905074 DOI: 10.1021/cr2003129] [Citation(s) in RCA: 185] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Qingjun Liu
- Biosensor National Special Laboratory, Key Laboratory of Biomedical Engineering of the Ministry of Education, Department of Biomedical Engineering, Zhejiang University , Hangzhou 310027, China
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20
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Hosseinzadeh Z, Almilaji A, Honisch S, Pakladok T, Liu G, Bhavsar SK, Ruth P, Shumilina E, Lang F. Upregulation of the large conductance voltage- and Ca2+-activated K+ channels by Janus kinase 2. Am J Physiol Cell Physiol 2014; 306:C1041-9. [PMID: 24696148 DOI: 10.1152/ajpcell.00209.2013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The iberiotoxin-sensitive large conductance voltage- and Ca(2+)-activated potassium (BK) channels (maxi-K(+)-channels) hyperpolarize the cell membrane thus supporting Ca(2+) entry through Ca(2+)-release activated Ca(2+) channels. Janus kinase-2 (JAK2) has been identified as novel regulator of ion transport. To explore whether JAK2 participates in the regulation of BK channels, cRNA encoding Ca(2+)-insensitive BK channels (BK(M513I+Δ899-903)) was injected into Xenopus oocytes with or without cRNA encoding wild-type JAK2, gain-of-function (V617F)JAK2, or inactive (K882E)JAK2. K(+) conductance was determined by dual electrode voltage clamp and BK-channel protein abundance by confocal microscopy. In A204 alveolar rhabdomyosarcoma cells, iberiotoxin-sensitive K(+) current was determined utilizing whole cell patch clamp. A204 cells were further transfected with JAK2 and BK-channel transcript, and protein abundance was quantified by RT-PCR and Western blotting, respectively. As a result, the K(+) current in BK(M513I+Δ899-903)-expressing oocytes was significantly increased following coexpression of JAK2 or (V617F)JAK2 but not (K882E)JAK2. Coexpression of the BK channel with (V617F)JAK2 but not (K882E)JAK2 enhanced BK-channel protein abundance in the oocyte cell membrane. Exposure of BK-channel and (V617F)JAK2-expressing oocytes to the JAK2 inhibitor AG490 (40 μM) significantly decreased K(+) current. Inhibition of channel insertion by brefeldin A (5 μM) decreased the K(+) current to a similar extent in oocytes expressing the BK channel alone and in oocytes expressing the BK channel and (V617F)JAK2. The iberiotoxin (50 nM)-sensitive K(+) current in rhabdomyosarcoma cells was significantly decreased by AG490 pretreatment (40 μM, 12 h). Moreover, overexpression of JAK2 in A204 cells significantly enhanced BK channel mRNA and protein abundance. In conclusion, JAK2 upregulates BK channels by increasing channel protein abundance in the cell membrane.
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Affiliation(s)
| | - Ahmad Almilaji
- Department of Physiology, University of Tübingen, Tübingen, Germany; and
| | - Sabina Honisch
- Department of Physiology, University of Tübingen, Tübingen, Germany; and
| | - Tatsiana Pakladok
- Department of Physiology, University of Tübingen, Tübingen, Germany; and
| | - GuoXing Liu
- Department of Physiology, University of Tübingen, Tübingen, Germany; and
| | - Shefalee K Bhavsar
- Department of Physiology, University of Tübingen, Tübingen, Germany; and
| | - Peter Ruth
- Institute of Pharmacy, Department of Pharmacology and Toxicology, University of Tübingen, Tübingen, Germany
| | | | - Florian Lang
- Department of Physiology, University of Tübingen, Tübingen, Germany; and
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21
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Liu Y, Hitomi H, Diah S, Deguchi K, Mori H, Masaki T, Nakano D, Kobori H, Nishiyama A. Roles of Na⁺/H⁺ exchanger type 1 and intracellular pH in angiotensin II-induced reactive oxygen species generation and podocyte apoptosis. J Pharmacol Sci 2014; 122:176-83. [PMID: 23800993 DOI: 10.1254/jphs.12291fp] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
A growing body of evidence suggests that podocyte apoptosis is a major cause of decreased podocyte number, which leads to albuminuria and glomerular injury. The aim of this study was to clarify the molecular mechanisms of angiotensin II (Ang II)-induced apoptosis in cultured mouse podocytes. We examined the effects of Ang II (100 nmol/L) on apoptosis, superoxide anions, and cytosol pH in podocytes. For intracellular pH measurements, image analysis was conducted using confocal laser microscopy after incubation with carboxy-seminaphthorhodafluor-1. Superoxide anions and intracellular pH were elevated with Ang II treatment. Apoptotic cell numbers, as measured by TUNEL staining and caspase 3 activity, were also augmented in the Ang II-treated group. Pre-treatment with olmesartan (100 nmol/L, an Ang II type 1-receptor blocker), apocynin (50 μmol/L, NADPH oxidase inhibitor), or 5-N,N hexamethylene amiloride [30 μmol/L, Na⁺/H⁺ exchanger type 1 (NHE-1) inhibitor] abolished Ang II-induced podocyte apoptosis, whereas NHE-1 mRNA and protein expression was not affected by Ang II treatment. Moreover, Ang II increased NHE-1 phosphorylation. These results suggest that superoxide production, NHE-1 activation, and intracellular alkalization were early features prior to apoptosis in Ang II-treated mouse podocytes, and may offer new insights into the mechanisms responsible for Ang II-induced podocyte injury.
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Affiliation(s)
- Ya Liu
- Department of Pharmacology, Faculty of Medicine, Kagawa University, Japan
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22
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Na+/H+ exchanger-1 reduces podocyte injury caused by endoplasmic reticulum stress via autophagy activation. J Transl Med 2014; 94:439-54. [PMID: 24566932 DOI: 10.1038/labinvest.2014.4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 12/14/2013] [Accepted: 12/30/2013] [Indexed: 12/26/2022] Open
Abstract
Podocyte injury has a critical role in the pathogenesis of proteinuria. Induction of endoplasmic reticulum (ER) stress is thought to lead to podocyte injury; however, no effective strategy for reducing ER stress-induced injury has been identified. We investigated specific mechanisms for reducing podocyte injury caused by ER stress. We found that the induction of ER stress in podocytes was related to cytoskeleton injury and increased proteinuria, which was associated with autophagy activation and downregulation of Na(+)/H(+) exchanger-1 (NHE-1) in the rat model of passive Heymann nephritis. Using mouse podocyte cells (MPCs), we showed that ER stress could lead to podocyte injury accompanied by autophagy activation, and the disturbance of autophagy aggravated cytoskeleton loss under conditions of ER stress. The balance between autophagy activation and ER stress was critical to podocyte survival, in which the efficiency of autophagy could have a pivotal role. Strikingly, the overexpression and small interfering RNA knockdown of NHE-1 results suggested that NHE-1 exerts a protective effect by reducing the loss of synaptopodin in MPCs exposed to ER stress. This protective mechanism involves NHE-1 activation of autophagy via the PI3K/Akt pathway to reduce ER stress injury in podocytes. This mechanism may provide a new pathway to prevent podocyte injury.
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Hosseinzadeh Z, Luo D, Sopjani M, Bhavsar SK, Lang F. Down-regulation of the epithelial Na⁺ channel ENaC by Janus kinase 2. J Membr Biol 2014; 247:331-8. [PMID: 24562791 DOI: 10.1007/s00232-014-9636-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 01/29/2014] [Indexed: 11/26/2022]
Abstract
Janus kinase-2 (JAK2), a signaling molecule mediating effects of various hormones including leptin and growth hormone, has previously been shown to modify the activity of several channels and carriers. Leptin is known to inhibit and growth hormone to stimulate epithelial Na(+) transport, effects at least partially involving regulation of the epithelial Na(+) channel ENaC. However, no published evidence is available regarding an influence of JAK2 on the activity of the epithelial Na(+) channel ENaC. In order to test whether JAK2 participates in the regulation of ENaC, cRNA encoding ENaC was injected into Xenopus oocytes with or without additional injection of cRNA encoding wild type JAK2, gain-of-function (V617F)JAK2 or inactive (K882E)JAK2. Moreover, ENaC was expressed with or without the ENaC regulating ubiquitin ligase Nedd4-2 with or without JAK2, (V617F)JAK2 or (K882E)JAK2. ENaC was determined from amiloride (50 μM)-sensitive current (I(amil)) in dual electrode voltage clamp. Moreover, I(amil) was determined in colonic tissue utilizing Ussing chambers. As a result, the I(amil) in ENaC-expressing oocytes was significantly decreased following coexpression of JAK2 or (V617F)JAK2, but not by coexpression of (K882E)JAK2. Coexpression of JAK2 and Nedd4-2 decreased I(amil) in ENaC-expressing oocytes to a larger extent than coexpression of Nedd4-2 alone. Exposure of ENaC- and JAK2-expressing oocytes to JAK2 inhibitor AG490 (40 μM) significantly increased I(amil). In colonic epithelium, I(amil) was significantly enhanced by AG490 pretreatment (40 μM, 1 h). In conclusion, JAK2 is a powerful inhibitor of ENaC.
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Affiliation(s)
- Zohreh Hosseinzadeh
- Department of Physiology, University of Tübingen, Gmelinstr. 5, 72076, Tübingen, Germany
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24
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Reiser J, Sever S, Faul C. Signal transduction in podocytes--spotlight on receptor tyrosine kinases. Nat Rev Nephrol 2014; 10:104-15. [PMID: 24394191 PMCID: PMC4109315 DOI: 10.1038/nrneph.2013.274] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The mammalian kidney filtration barrier is a complex multicellular, multicomponent structure that maintains homeostasis by regulating electrolytes, acid-base balance, and blood pressure (via maintenance of salt and water balance). To perform these multiple functions, podocytes--an important component of the filtration apparatus--must process a series of intercellular signals. Integrating these signals with diverse cellular responses enables a coordinated response to various conditions. Although mature podocytes are terminally differentiated and cannot proliferate, they are able to respond to growth factors. It is possible that the initial response of podocytes to growth factors is beneficial and protective, and might include the induction of hypertrophic cell growth. However, extended and/or uncontrolled growth factor signalling might be maladaptive and could result in the induction of apoptosis and podocyte loss. Growth factors signal via the activation of receptor tyrosine kinases (RTKs) on their target cells and around a quarter of the 58 RTK family members that are encoded in the human genome have been identified in podocytes. Pharmacological inhibitors of many RTKs exist and are currently used in experimental and clinical cancer therapy. The identification of pathological RTK-mediated signal transduction pathways in podocytes could provide a starting point for the development of novel therapies for glomerular disorders.
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Affiliation(s)
- Jochen Reiser
- Department of Medicine, Rush University Medical Center, 1735 West Harrison Street, Cohn Building, Suite 724, Chicago, IL 60612, USA
| | - Sanja Sever
- Department of Medicine, Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, 149 13th Street, Charlestown, MA 02129, USA
| | - Christian Faul
- Division of Nephrology and Hypertension, University of Miami Miller School of Medicine, 1580 North West 10th Avenue (R-762), Batchelor Building 626, Miami, FL 33136, USA
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25
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Saad S, Peter M, Dechant R. In scarcity and abundance: metabolic signals regulating cell growth. Physiology (Bethesda) 2014; 28:298-309. [PMID: 23997189 DOI: 10.1152/physiol.00005.2013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Although nutrient availability is a major driver of cell growth, and continuous adaptation to nutrient supply is critical for the development and survival of all organisms, the molecular mechanisms of nutrient sensing are only beginning to emerge. Here, we highlight recent advances in the field of nutrient sensing and discuss arising principles governing how metabolism might regulate growth-promoting pathways. In addition, we discuss signaling functions of metabolic enzymes not directly related to their metabolic activity.
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Affiliation(s)
- Shady Saad
- Institute of Biochemistry, ETH Zurich, Zurich, Switzerland
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26
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Berchtold MW, Villalobo A. The many faces of calmodulin in cell proliferation, programmed cell death, autophagy, and cancer. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1843:398-435. [PMID: 24188867 DOI: 10.1016/j.bbamcr.2013.10.021] [Citation(s) in RCA: 221] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2013] [Revised: 10/24/2013] [Accepted: 10/26/2013] [Indexed: 12/21/2022]
Abstract
Calmodulin (CaM) is a ubiquitous Ca(2+) receptor protein mediating a large number of signaling processes in all eukaryotic cells. CaM plays a central role in regulating a myriad of cellular functions via interaction with multiple target proteins. This review focuses on the action of CaM and CaM-dependent signaling systems in the control of vertebrate cell proliferation, programmed cell death and autophagy. The significance of CaM and interconnected CaM-regulated systems for the physiology of cancer cells including tumor stem cells, and processes required for tumor progression such as growth, tumor-associated angiogenesis and metastasis are highlighted. Furthermore, the potential targeting of CaM-dependent signaling processes for therapeutic use is discussed.
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Key Words
- (4-[3,5-bis-[2-(4-hydroxy-3-methoxy-phenyl)-ethyl]-4,5-dihydro-pyrazol-1-yl]-benzoic acid
- (4-[3,5-bis-[2-(4-hydroxy-3-methoxy-phenyl)-vinyl]-4,5-dihydro-pyrazol-1-yl]-phenyl)-(4-methyl-piperazin-1-yl)-methanone
- (−) enantiomer of dihydropyrine 3-methyl-5-3-(4,4-diphenyl-1-piperidinyl)-propyl-1,4-dihydro-2,6-dimethyl-4-(3-nitrophenyl)-piridine-3,5-dicarboxylate-hydrochloride (niguldipine)
- 1-[N,O-bis(5-isoquinolinesulfonyl)-N-methyl-l-tyrosyl]-4-phenylpiperazine
- 12-O-tetradecanoyl-phorbol-13-acetate
- 2-chloro-(ε-amino-Lys(75))-[6-(4-(N,N′-diethylaminophenyl)-1,3,5-triazin-4-yl]-CaM adduct
- 3′-(β-chloroethyl)-2′,4′-dioxo-3,5′-spiro-oxazolidino-4-deacetoxy-vinblastine
- 7,12-dimethylbenz[a]anthracene
- Apoptosis
- Autophagy
- B859-35
- CAPP(1)-CaM
- Ca(2+) binding protein
- Calmodulin
- Cancer biology
- Cell proliferation
- DMBA
- EBB
- FL-CaM
- FPCE
- HBC
- HBCP
- J-8
- KAR-2
- KN-62
- KN-93
- N-(4-aminobutyl)-2-naphthalenesulfonamide
- N-(4-aminobutyl)-5-chloro-2-naphthalenesulfonamide
- N-(6-aminohexyl)-1-naphthalenesulfonamide
- N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide
- N-8-aminooctyl-5-iodo-naphthalenesulfonamide
- N-[2-[N-(4-chlorocinnamyl)-N-methylaminomethyl]phenyl]-N-(2-hydroxyethyl)-4-methoxybenzenesulfonamide
- O-(4-ethoxyl-butyl)-berbamine
- RITC-CaM
- TA-CaM
- TFP
- TPA
- W-12
- W-13
- W-5
- W-7
- fluorescein-CaM adduct
- fluphenazine-N-2-chloroethane
- norchlorpromazine-CaM adduct
- rhodamine isothiocyanate-CaM adduct
- trifluoperazine
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Affiliation(s)
- Martin W Berchtold
- Department of Biology, University of Copenhagen, Copenhagen Biocenter 4-2-09 Ole Maaløes Vej 5, DK-2200 Copenhagen N, Denmark.
| | - Antonio Villalobo
- Instituto de Investigaciones Biomédicas, Department of Cancer Biology, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, c/Arturo Duperier 4, E-28029 Madrid, Spain.
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27
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Li X, Prins D, Michalak M, Fliegel L. Calmodulin-dependent binding to the NHE1 cytosolic tail mediates activation of the Na+/H+ exchanger by Ca2+ and endothelin. Am J Physiol Cell Physiol 2013; 305:C1161-9. [PMID: 24088894 DOI: 10.1152/ajpcell.00208.2013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The mammalian Na(+)/H(+) exchanger isoform 1 (NHE1) is a ubiquitous plasma membrane protein that regulates intracellular pH by removing a single proton (H(+)) in exchange for one extracellular Na(+). The human protein contains a ∼500-amino acid membrane domain and a regulatory, ∼315-amino acid cytosolic domain. NHE1 is activated by a number of hormones including endothelin (ET) and by Ca(2+). The regulatory tail possesses an inhibitory calmodulin (CaM)-binding domain, and inhibition of NHE1 is relieved by binding of a Ca(2+)-CaM complex. We examined the dynamics of ET-1 and Ca(2+) regulation of binding to NHE1 in vivo. CFP was linked to the NHE1 protein cytoplasmic COOH terminus. This was stably transfected into AP-1 cells that are devoid of their own NHE1 protein. The protein was expressed and targeted properly and retained NHE1 activity comparable to the wild-type protein. We examined the in vivo coupling of NHE1 to CaM by Förster resonance energy transfer using CaM linked to the fluorescent protein Venus. CaM interaction with NHE1 was dynamic. Removal of serum reduced CaM interaction with NHE1. Addition of the Ca(2+) ionophore ionomycin increased the interaction between CaM and NHE1. We expressed an ET receptor in AP-1 cells and also found a time-dependent association of NHE1 with CaM in vivo that was dependent on ET treatment. The results are the first demonstration of the in vivo association of NHE1 and CaM through ET-dependent signaling pathways.
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Affiliation(s)
- Xiuju Li
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
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28
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Lopez-Haber C, Kazanietz MG. Cucurbitacin I inhibits Rac1 activation in breast cancer cells by a reactive oxygen species-mediated mechanism and independently of Janus tyrosine kinase 2 and P-Rex1. Mol Pharmacol 2013; 83:1141-54. [PMID: 23478800 DOI: 10.1124/mol.112.084293] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The small GTPase Rac1 has been widely implicated in mammary tumorigenesis and metastasis. Previous studies established that stimulation of ErbB receptors in breast cancer cells activates Rac1 and enhances motility via the Rac-guanine nucleotide exchange factor P-Rex1. As the Janus tyrosine kinase 2 (Jak2)/signal transducer and activator of transcription 3 (Stat3) pathway has been shown to be functionally associated with ErbB receptors, we asked if this pathway could mediate P-Rex1/Rac1 activation in response to ErbB ligands. Here we found that the anticancer agent cucurbitacin I, a Jak2 inhibitor, reduced the activation of Rac1 and motility in response to the ErbB3 ligand heregulin in breast cancer cells. However, Rac1 activation was not affected by Jak2 or Stat3 RNA interference, suggesting that the effect of cucurbitacin I occurs through a Jak2-independent mechanism. Cucurbitacin I also failed to affect the activation of P-Rex1 by heregulin. Subsequent analysis revealed that cucurbitacin I strongly activates RhoA and the Rho effector Rho kinase (ROCK) in breast cancer cells and induces the formation of stress fibers. Interestingly, disruption of the RhoA-ROCK pathway prevented the inhibitory effect of cucurbitacin I on Rac1 activation by heregulin. Lastly, we found that RhoA activation by cucurbitacin I is mediated by reactive oxygen species (ROS). The ROS scavenger N-acetyl L-cysteine and the mitochondrial antioxidant Mito-TEMPO rescued the inhibitory effect of cucurbitacin I on Rac1 activation. In conclusion, these results indicate that ErbB-driven Rac1 activation in breast cancer cells proceeds independently of the Jak2 pathway. Moreover, they established that the inhibitory effect of cucurbitacin I on Rac1 activity involves the alteration of the balance between Rho and Rac.
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Affiliation(s)
- Cynthia Lopez-Haber
- Department of Pharmacology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6160, USA
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29
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Zhou C, Baltz JM. JAK2 mediates the acute response to decreased cell volume in mouse preimplantation embryos by activating NHE1. J Cell Physiol 2012; 228:428-38. [DOI: 10.1002/jcp.24147] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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30
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Flamant M, Bollee G, Henique C, Tharaux PL. Epidermal growth factor: a new therapeutic target in glomerular disease. Nephrol Dial Transplant 2012; 27:1297-304. [DOI: 10.1093/ndt/gfs030] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
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31
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Downregulation of the Creatine Transporter SLC6A8 by JAK2. J Membr Biol 2012; 245:157-63. [DOI: 10.1007/s00232-012-9424-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2011] [Accepted: 02/16/2012] [Indexed: 12/20/2022]
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32
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Hosseinzadeh Z, Shojaiefard M, Bhavsar SK, Lang F. Up-regulation of the betaine/GABA transporter BGT1 by JAK2. Biochem Biophys Res Commun 2012; 420:172-7. [DOI: 10.1016/j.bbrc.2012.02.137] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Accepted: 02/24/2012] [Indexed: 11/17/2022]
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33
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Hosseinzadeh Z, Bhavsar SK, Lang F. Down-Regulation of the Myoinositol Transporter SMIT by JAK2. Cell Physiol Biochem 2012. [DOI: 10.1159/000343335] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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34
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De Giusti VC, Nolly MB, Yeves AM, Caldiz CI, Villa-Abrille MC, Chiappe de Cingolani GE, Ennis IL, Cingolani HE, Aiello EA. Aldosterone Stimulates the Cardiac Na
+
/H
+
Exchanger via Transactivation of the Epidermal Growth Factor Receptor. Hypertension 2011; 58:912-9. [DOI: 10.1161/hypertensionaha.111.176024] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The use of antagonists of the mineralocorticoid receptor in the treatment of myocardial hypertrophy and heart failure has gained increasing importance in the last years. The cardiac Na
+
/H
+
exchanger (NHE-1) upregulation induced by aldosterone could account for the genesis of these pathologies. We tested whether aldosterone-induced NHE-1 stimulation involves the transactivation of the epidermal growth factor receptor (EGFR). Rat ventricular myocytes were used to measure intracellular pH with epifluorescence. Aldosterone enhanced the NHE-1 activity. This effect was canceled by spironolactone or eplerenone (mineralocorticoid receptor antagonists), but not by mifepristone (glucocorticoid receptor antagonist) or cycloheximide (protein synthesis inhibitor), indicating that the mechanism is mediated by the mineralocorticoid receptor triggering nongenomic pathways. Aldosterone-induced NHE-1 stimulation was abolished by the EGFR kinase inhibitor AG1478, suggesting that is mediated by transactivation of EGFR. The increase in the phosphorylation level of the kinase p90
RSK
and NHE-1 serine703 induced by aldosterone was also blocked by AG1478. Exogenous epidermal growth factor mimicked the effects of aldosterone on NHE-1 activity. Epidermal growth factor was also able to increase reactive oxygen species production, and the epidermal growth factor–induced activation of the NHE-1 was abrogated by the reactive oxygen species scavenger
N
-2-mercaptopropionyl glycine, indicating that reactive oxygen species are participating as signaling molecules in this mechanism. Aldosterone enhances the NHE-1 activity via transactivation of the EGFR, formation of reactive oxygen species, and phosphorylation of the exchanger. These results call attention to the consideration of the EGFR as a new potential therapeutic target of the cardiovascular pathologies involving the participation of aldosterone.
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Affiliation(s)
- Verónica C. De Giusti
- From the Centro de Investigaciones Cardiovasculares (CONICET), Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Mariela B. Nolly
- From the Centro de Investigaciones Cardiovasculares (CONICET), Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Alejandra M. Yeves
- From the Centro de Investigaciones Cardiovasculares (CONICET), Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Claudia I. Caldiz
- From the Centro de Investigaciones Cardiovasculares (CONICET), Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - María C. Villa-Abrille
- From the Centro de Investigaciones Cardiovasculares (CONICET), Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Gladys E. Chiappe de Cingolani
- From the Centro de Investigaciones Cardiovasculares (CONICET), Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Irene L. Ennis
- From the Centro de Investigaciones Cardiovasculares (CONICET), Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Horacio E. Cingolani
- From the Centro de Investigaciones Cardiovasculares (CONICET), Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Ernesto A. Aiello
- From the Centro de Investigaciones Cardiovasculares (CONICET), Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
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35
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Banday AA, Lokhandwala MF. Oxidative Stress Causes Renal Angiotensin II Type 1 Receptor Upregulation, Na
+
/H
+
Exchanger 3 Overstimulation, and Hypertension. Hypertension 2011; 57:452-9. [DOI: 10.1161/hypertensionaha.110.162339] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Anees A. Banday
- From the Heart and Kidney Institute, College of Pharmacy, University of Houston, Houston, TX
| | - Mustafa F. Lokhandwala
- From the Heart and Kidney Institute, College of Pharmacy, University of Houston, Houston, TX
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36
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Sánchez-González P, Jellali K, Villalobo A. Calmodulin-mediated regulation of the epidermal growth factor receptor. FEBS J 2009; 277:327-42. [PMID: 19951361 DOI: 10.1111/j.1742-4658.2009.07469.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this review, we first describe the mechanisms by which the epidermal growth factor receptor generates a Ca(2+) signal and, subsequently, we compile the available experimental evidence regarding the role that the Ca(2+)/calmodulin complex, formed after the rise in cytosolic free Ca(2+) concentration, exerts on the receptor. We focus not only on the indirect action that Ca(2+)/calmodulin exerts on the epidermal growth factor receptor, as a result of the activation of distinct calmodulin-dependent kinases, but also, and more extensively, on the direct interaction of Ca(2+)/calmodulin with the receptor. We also describe several mechanistic models that could account for the Ca(2+)/calmodulin-mediated regulation of epidermal growth factor receptor activity. The control exerted by calmodulin on distinct epidermal growth factor receptor-mediated cellular functions is also discussed. Finally, the phosphorylation of this Ca(2+) sensor by the epidermal growth factor receptor is highlighted.
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Affiliation(s)
- Pablo Sánchez-González
- Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
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