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Koning ASCAM, Buurstede JC, van Weert LTCM, Meijer OC. Glucocorticoid and Mineralocorticoid Receptors in the Brain: A Transcriptional Perspective. J Endocr Soc 2019; 3:1917-1930. [PMID: 31598572 PMCID: PMC6777400 DOI: 10.1210/js.2019-00158] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 07/18/2019] [Indexed: 02/07/2023] Open
Abstract
Adrenal glucocorticoid hormones are crucial for maintenance of homeostasis and adaptation to stress. They act via the mineralocorticoid receptors (MRs) and glucocorticoid receptors (GRs)-members of the family of nuclear receptors. MRs and GRs can mediate distinct, sometimes opposite, effects of glucocorticoids. Both receptor types can mediate nongenomic steroid effects, but they are best understood as ligand-activated transcription factors. MR and GR protein structure is similar; the receptors can form heterodimers on the DNA at glucocorticoid response elements (GREs), and they share a number of target genes. The transcriptional basis for opposite effects on cellular physiology remains largely unknown, in particular with respect to MR-selective gene transcription. In this review, we discuss proven and potential mechanisms of transcriptional specificity for MRs and GRs. These include unique GR binding to "negative GREs," direct binding to other transcription factors, and binding to specific DNA sequences in conjunction with other transcription factors, as is the case for MRs and NeuroD proteins in the brain. MR- and GR-specific effects may also depend on specific interactions with transcriptional coregulators, downstream mediators of transcriptional receptor activity. Current data suggest that the relative importance of these mechanisms depends on the tissue and physiological context. Insight into these processes may not only allow a better understanding of homeostatic regulation but also the development of drugs that target specific aspects of disease.
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Affiliation(s)
- Anne-Sophie C A M Koning
- Einthoven Laboratory and Department of Medicine, Division of Endocrinology, Leiden University Medical Center, RC Leiden, Netherlands
| | - Jacobus C Buurstede
- Einthoven Laboratory and Department of Medicine, Division of Endocrinology, Leiden University Medical Center, RC Leiden, Netherlands
| | - Lisa T C M van Weert
- Einthoven Laboratory and Department of Medicine, Division of Endocrinology, Leiden University Medical Center, RC Leiden, Netherlands
| | - Onno C Meijer
- Einthoven Laboratory and Department of Medicine, Division of Endocrinology, Leiden University Medical Center, RC Leiden, Netherlands
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52
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Yanda MK, Cha B, Cebotaru CV, Cebotaru L. Pharmacological reversal of renal cysts from secretion to absorption suggests a potential therapeutic strategy for managing autosomal dominant polycystic kidney disease. J Biol Chem 2019; 294:17090-17104. [PMID: 31570523 DOI: 10.1074/jbc.ra119.010320] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 09/26/2019] [Indexed: 12/19/2022] Open
Abstract
Autosomal-dominant polycystic kidney disease (ADPKD) induces a secretory phenotype, resulting in multiple fluid-filled cysts. We have previously demonstrated that VX-809, a corrector of the cystic fibrosis transmembrane conductance regulator (CFTR), reduces cyst growth. Here, we show that in normal mice CFTR is located within the cells and also at the apical and basolateral membranes. However, in polycystic kidney disease (pkd1)-knockout mice, CFTR was located at the plasma membrane, consistent with its role in cAMP-dependent fluid secretion. In cystic mice, VX-809 treatment increased CFTR levels at the apical membrane and reduced its association with the endoplasmic reticulum. Surprisingly, VX-809 treatment significantly increased CFTR's co-localization with the basolateral membrane in cystic mice. Na+/H+ exchanger 3 (NHE3) is present in pkd1-knockout and normal mice and in proximal tubule-derived, cultured pkd1-knockout cells. VX-809 increased the expression, activity, and apical plasma membrane localization of NHE3. Co-localization of epithelial sodium channel (ENaC) with the plasma membrane was reduced in cysts in pkd1-knockout mice, consistent with an inability of the cysts to absorb fluid. Interestingly, in the cystic mice, VX-809 treatment increased ENaC levels at the apical plasma membrane consistent with fluid absorption. Thus, VX-809 treatment of pkd1-null mouse kidneys significantly affected CFTR, NHE3, and ENaC, altering the cyst phenotype from one poised toward fluid secretion toward one more favorable for absorption. VX-809 also altered the location of CFTR but not of NHE3 or ENaC in normal mice. Given that VX-809 administration is safe, it may have potential utility for treating patients with ADPKD.
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Affiliation(s)
- Murali K Yanda
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Boyoung Cha
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Cristina V Cebotaru
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Liudmila Cebotaru
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
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53
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van der Wijst J, Belge H, Bindels RJM, Devuyst O. Learning Physiology From Inherited Kidney Disorders. Physiol Rev 2019; 99:1575-1653. [PMID: 31215303 DOI: 10.1152/physrev.00008.2018] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The identification of genes causing inherited kidney diseases yielded crucial insights in the molecular basis of disease and improved our understanding of physiological processes that operate in the kidney. Monogenic kidney disorders are caused by mutations in genes coding for a large variety of proteins including receptors, channels and transporters, enzymes, transcription factors, and structural components, operating in specialized cell types that perform highly regulated homeostatic functions. Common variants in some of these genes are also associated with complex traits, as evidenced by genome-wide association studies in the general population. In this review, we discuss how the molecular genetics of inherited disorders affecting different tubular segments of the nephron improved our understanding of various transport processes and of their involvement in homeostasis, while providing novel therapeutic targets. These include inherited disorders causing a dysfunction of the proximal tubule (renal Fanconi syndrome), with emphasis on epithelial differentiation and receptor-mediated endocytosis, or affecting the reabsorption of glucose, the handling of uric acid, and the reabsorption of sodium, calcium, and magnesium along the kidney tubule.
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Affiliation(s)
- Jenny van der Wijst
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center , Nijmegen , The Netherlands ; Institute of Physiology, University of Zurich , Zurich , Switzerland ; and Division of Nephrology, Institute of Experimental and Clinical Research (IREC), Medical School, Université catholique de Louvain, Brussels, Belgium
| | - Hendrica Belge
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center , Nijmegen , The Netherlands ; Institute of Physiology, University of Zurich , Zurich , Switzerland ; and Division of Nephrology, Institute of Experimental and Clinical Research (IREC), Medical School, Université catholique de Louvain, Brussels, Belgium
| | - René J M Bindels
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center , Nijmegen , The Netherlands ; Institute of Physiology, University of Zurich , Zurich , Switzerland ; and Division of Nephrology, Institute of Experimental and Clinical Research (IREC), Medical School, Université catholique de Louvain, Brussels, Belgium
| | - Olivier Devuyst
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center , Nijmegen , The Netherlands ; Institute of Physiology, University of Zurich , Zurich , Switzerland ; and Division of Nephrology, Institute of Experimental and Clinical Research (IREC), Medical School, Université catholique de Louvain, Brussels, Belgium
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Enslow BT, Stockand JD, Berman JM. Liddle's syndrome mechanisms, diagnosis and management. Integr Blood Press Control 2019; 12:13-22. [PMID: 31564964 PMCID: PMC6731958 DOI: 10.2147/ibpc.s188869] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Accepted: 08/23/2019] [Indexed: 12/26/2022] Open
Abstract
Liddle's syndrome is a genetic disorder characterized by hypertension with hypokalemic metabolic alkalosis, hyporeninemia and suppressed aldosterone secretion that often appears early in life. It results from inappropriately elevated sodium reabsorption in the distal nephron. Liddle's syndrome is caused by mutations to subunits of the Epithelial Sodium Channel (ENaC). Among other mechanisms, such mutations typically prevent ubiquitination of these subunits, slowing the rate at which they are internalized from the membrane, resulting in an elevation of channel activity. A minority of Liddle's syndrome mutations, though, result in a complementary effect that also elevates activity by increasing the probability that ENaC channels within the membrane are open. Potassium-sparing diuretics such as amiloride and triamterene reduce ENaC activity, and in combination with a reduced sodium diet can restore normotension and electrolyte imbalance in Liddle's syndrome patients and animal models. Liddle's syndrome can be diagnosed clinically by phenotype and confirmed through genetic testing. This review examines the clinical features of Liddle's syndrome, the differential diagnosis of Liddle's syndrome and differentiation from other genetic diseases with similar phenotype, and what is currently known about the population-level prevalence of Liddle's syndrome. This review gives special focus to the molecular mechanisms of Liddle's syndrome.
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Affiliation(s)
| | | | - Jonathan M Berman
- New York Institute of Technology College of Osteopathic Medicine at Arkansas State University, Jonesboro, AR, USA
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55
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Fructose increases the activity of sodium hydrogen exchanger in renal proximal tubules that is dependent on ketohexokinase. J Nutr Biochem 2019; 71:54-62. [DOI: 10.1016/j.jnutbio.2019.05.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 05/20/2019] [Accepted: 05/21/2019] [Indexed: 11/22/2022]
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56
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van Weert LTCM, Buurstede JC, Sips HCM, Vettorazzi S, Mol IM, Hartmann J, Prekovic S, Zwart W, Schmidt MV, Roozendaal B, Tuckermann JP, Sarabdjitsingh RA, Meijer OC. Identification of mineralocorticoid receptor target genes in the mouse hippocampus. J Neuroendocrinol 2019; 31:e12735. [PMID: 31121060 PMCID: PMC6771480 DOI: 10.1111/jne.12735] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 05/10/2019] [Accepted: 05/10/2019] [Indexed: 02/06/2023]
Abstract
Brain mineralocorticoid receptors (MRs) and glucocorticoid receptors (GRs) respond to the same glucocorticoid hormones but can have differential effects on cellular function. Several lines of evidence suggest that MR-specific target genes must exist and might underlie the distinct effects of the receptors. The present study aimed to identify MR-specific target genes in the hippocampus, a brain region where MR and GR are co-localised and play a role in the stress response. Using genome-wide binding of both receptor types, we previously identified MR-specific, MR-GR overlapping and GR-specific putative target genes. We now report altered gene expression levels of such genes in the hippocampus of forebrain MR knockout (fbMRKO) mice, killed at the time of their endogenous corticosterone peak. Of those genes associated with MR-specific binding, the most robust effect was a 50% reduction in Jun dimerization protein 2 (Jdp2) mRNA levels in fbMRKO mice. Down-regulation was also observed for the MR-specific Nitric oxide synthase 1 adaptor protein (Nos1ap) and Suv3 like RNA helicase (Supv3 l1). Interestingly, the classical glucocorticoid target gene FK506 binding protein 5 (Fkbp5), which is associated with MR and GR chromatin binding, was expressed at substantially lower levels in fbMRKO mice. Subsequently, hippocampal Jdp2 was confirmed to be up-regulated in a restraint stress model, posing Jdp2 as a bona fide MR target that is also responsive in an acute stress condition. Thus, we show that MR-selective DNA binding can reveal functional regulation of genes and further identify distinct MR-specific effector pathways.
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Affiliation(s)
- Lisa T. C. M. van Weert
- Einthoven LaboratoryDivision of EndocrinologyDepartment of MedicineLeiden University Medical CenterLeidenThe Netherlands
- Department of Cognitive NeuroscienceRadboud University Medical CenterNijmegenThe Netherlands
- Donders Institute for Brain, Cognition and BehaviourRadboud UniversityNijmegenThe Netherlands
| | - Jacobus C. Buurstede
- Einthoven LaboratoryDivision of EndocrinologyDepartment of MedicineLeiden University Medical CenterLeidenThe Netherlands
| | - Hetty C. M. Sips
- Einthoven LaboratoryDivision of EndocrinologyDepartment of MedicineLeiden University Medical CenterLeidenThe Netherlands
| | - Sabine Vettorazzi
- Institute of Comparative Molecular EndocrinologyUniversity of UlmUlmGermany
| | - Isabel M. Mol
- Einthoven LaboratoryDivision of EndocrinologyDepartment of MedicineLeiden University Medical CenterLeidenThe Netherlands
| | - Jakob Hartmann
- Department of PsychiatryHarvard Medical SchoolMcLean HospitalBelmontMassachusetts
| | - Stefan Prekovic
- Division of OncogenomicsOncode InstituteThe Netherlands Cancer InstituteAmsterdamThe Netherlands
| | - Wilbert Zwart
- Division of OncogenomicsOncode InstituteThe Netherlands Cancer InstituteAmsterdamThe Netherlands
| | - Mathias V. Schmidt
- Department of Stress Neurobiology and NeurogeneticsMax Planck Institute of PsychiatryMunichGermany
| | - Benno Roozendaal
- Department of Cognitive NeuroscienceRadboud University Medical CenterNijmegenThe Netherlands
- Donders Institute for Brain, Cognition and BehaviourRadboud UniversityNijmegenThe Netherlands
| | - Jan P. Tuckermann
- Institute of Comparative Molecular EndocrinologyUniversity of UlmUlmGermany
| | - R. Angela Sarabdjitsingh
- Department of Translational NeuroscienceUMC Utrecht Brain CenterUniversity Medical CenterUtrechtThe Netherlands
| | - Onno C. Meijer
- Einthoven LaboratoryDivision of EndocrinologyDepartment of MedicineLeiden University Medical CenterLeidenThe Netherlands
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Spirli A, Cheval L, Debonneville A, Penton D, Ronzaud C, Maillard M, Doucet A, Loffing J, Staub O. The serine-threonine kinase PIM3 is an aldosterone-regulated protein in the distal nephron. Physiol Rep 2019; 7:e14177. [PMID: 31397090 PMCID: PMC6687858 DOI: 10.14814/phy2.14177] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 06/20/2019] [Accepted: 06/20/2019] [Indexed: 12/30/2022] Open
Abstract
The mineralocorticoid hormone aldosterone plays a crucial role in the control of Na+ and K+ balance, blood volume, and arterial blood pressure, by acting in the aldosterone-sensitive distal nephron (ASDN) and stimulating a complex transcriptional, translational, and cellular program. Because the complexity of the aldosterone response is still not fully appreciated, we aimed at identifying new elements in this pathway. Here, we demonstrate that the expression of the proto-oncogene PIM3 (Proviral Integration Site of Moloney Murine Leukemia Virus 3), a serine/threonine kinase belonging to the calcium/calmodulin-regulated group of kinases, is stimulated by aldosterone in vitro (mCCDcl1 cells), ex vivo (mouse kidney slices), and in vivo in mice. Characterizing a germline Pim3-/- mouse model, we found that these mice have an upregulated Renin-Angiotensin-Aldosterone System (RAAS), with high circulating aldosterone and plasma renin activity levels on both standard or Na+ -deficient diet. Surprisingly, we did not observe any obvious salt-losing phenotype in Pim3 KO mice as shown by normal blood pressure, plasma and urinary electrolytes, as well as unchanged expression levels of the major Na+ transport proteins. These observations suggest that the potential effects of the loss of the Pim3 gene are physiologically compensated. Indeed, the 2 other family members of the PIM kinase family, PIM1 and PIM2 are upregulated in the kidney of Pim3-/- mice, and may therefore be involved in such compensation. In conclusion, our data demonstrate that the PIM3 kinase is a novel aldosterone-induced protein, but its precise role in aldosterone-dependent renal homeostasis remains to be determined.
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Affiliation(s)
- Alessia Spirli
- Department of Pharmacology & ToxicologyUniversity of LausanneLausanneSwitzerland
- National Centre of Competence in Research “Kidney.ch”LausanneSwitzerland
| | - Lydie Cheval
- Centre de Recherche des CordeliersINSERM, Sorbonne Universités, USPC, Université Paris Descartes, Université Paris Diderot, Physiologie Rénale et TubulopathiesParisFrance
| | - Anne Debonneville
- Department of Pharmacology & ToxicologyUniversity of LausanneLausanneSwitzerland
- National Centre of Competence in Research “Kidney.ch”LausanneSwitzerland
| | - David Penton
- National Centre of Competence in Research “Kidney.ch”LausanneSwitzerland
- Institute of AnatomyUniversity of ZurichZurichSwitzerland
| | - Caroline Ronzaud
- Department of Pharmacology & ToxicologyUniversity of LausanneLausanneSwitzerland
- National Centre of Competence in Research “Kidney.ch”LausanneSwitzerland
| | - Marc Maillard
- Service of NephrologyLausanne University Hospital (CHUV)LausanneSwitzerland
| | - Alain Doucet
- Centre de Recherche des CordeliersINSERM, Sorbonne Universités, USPC, Université Paris Descartes, Université Paris Diderot, Physiologie Rénale et TubulopathiesParisFrance
| | - Johannes Loffing
- National Centre of Competence in Research “Kidney.ch”LausanneSwitzerland
- Institute of AnatomyUniversity of ZurichZurichSwitzerland
| | - Olivier Staub
- Department of Pharmacology & ToxicologyUniversity of LausanneLausanneSwitzerland
- National Centre of Competence in Research “Kidney.ch”LausanneSwitzerland
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58
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Manosroi W, Williams GH. Genetics of Human Primary Hypertension: Focus on Hormonal Mechanisms. Endocr Rev 2019; 40:825-856. [PMID: 30590482 PMCID: PMC6936319 DOI: 10.1210/er.2018-00071] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 09/07/2018] [Indexed: 02/06/2023]
Abstract
Increasingly, primary hypertension is being considered a syndrome and not a disease, with the individual causes (diseases) having a common sign-an elevated blood pressure. To determine these causes, genetic tools are increasingly employed. This review identified 62 proposed genes. However, only 21 of them met our inclusion criteria: (i) primary hypertension, (ii) two or more supporting cohorts from different publications or within a single publication or one supporting cohort with a confirmatory genetically modified animal study, and (iii) 600 or more subjects in the primary cohort; when including our exclusion criteria: (i) meta-analyses or reviews, (ii) secondary and monogenic hypertension, (iii) only hypertensive complications, (iv) genes related to blood pressure but not hypertension per se, (v) nonsupporting studies more common than supporting ones, and (vi) studies that did not perform a Bonferroni or similar multiassessment correction. These 21 genes were organized in a four-tiered structure: distant phenotype (hypertension); intermediate phenotype [salt-sensitive (18) or salt-resistant (0)]; subintermediate phenotypes under salt-sensitive hypertension [normal renin (4), low renin (8), and unclassified renin (6)]; and proximate phenotypes (specific genetically driven hypertensive subgroup). Many proximate hypertensive phenotypes had a substantial endocrine component. In conclusion, primary hypertension is a syndrome; many proposed genes are likely to be false positives; and deep phenotyping will be required to determine the utility of genetics in the treatment of hypertension. However, to date, the positive genes are associated with nearly 50% of primary hypertensives, suggesting that in the near term precise, mechanistically driven treatment and prevention strategies for the specific primary hypertension subgroups are feasible.
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Affiliation(s)
- Worapaka Manosroi
- Division of Endocrinology, Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.,Division of Endocrinology and Metabolism, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Gordon H Williams
- Division of Endocrinology, Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
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59
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D'Antona L, Dattilo V, Catalogna G, Scumaci D, Fiumara CV, Musumeci F, Perrotti G, Schenone S, Tallerico R, Spoleti CB, Costa N, Iuliano R, Cuda G, Amato R, Perrotti N. In Preclinical Model of Ovarian Cancer, the SGK1 Inhibitor SI113 Counteracts the Development of Paclitaxel Resistance and Restores Drug Sensitivity. Transl Oncol 2019; 12:1045-1055. [PMID: 31163384 PMCID: PMC6545392 DOI: 10.1016/j.tranon.2019.05.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 05/08/2019] [Accepted: 05/09/2019] [Indexed: 12/19/2022] Open
Abstract
Ovarian cancer is the second most common gynecological malignancy worldwide. Paclitaxel is particularly important in the therapy of ovarian carcinomas, but the treatment efficacy is counteracted by the development of resistance to chemotherapy. The identification of target molecules that can prevent or control the development of chemoresistance might provide important tools for the management of patients affected by ovarian cancer. Serum- and glucocorticoid-regulated kinase 1 (SGK1) appears to be a key determinant of resistance to chemo- and radiotherapy. Specifically, SGK1 affects paclitaxel sensitivity in RKO colon carcinoma cells by modulating the specificity protein 1 (SP1)–dependent expression of Ran-specific GTPase-activating protein (RANBP1), a member of the GTP-binding nuclear protein Ran (RAN) network that is required for the organization and function of the mitotic spindle. SGK1 inhibition might thus be useful for counteracting the development of paclitaxel resistance. Here, we present in vitro data obtained using ovarian carcinoma cell lines that indicate that the SGK1 inhibitor SI113 inhibits cancer cell proliferation, potentiates the effects of paclitaxel-based chemotherapy, counteracts the development of paclitaxel resistance, and restores paclitaxel sensitivity in paclitaxel-resistant A2780 ovarian cancer cells. The results were corroborated by preclinical studies of xenografts generated in nude mice through the implantation of paclitaxel-resistant human ovarian cancer cells. The SGK1 inhibitor SI113 synergizes with paclitaxel in the treatment of xenografted ovarian cancer cells. Taken together, these data suggest that SGK1 inhibition should be investigated in clinical trials for the treatment of paclitaxel-resistant ovarian cancer.
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Affiliation(s)
- Lucia D'Antona
- Department of "Scienze della Salute", University "Magna Graecia" of Catanzaro, Viale Europa, Catanzaro
| | - Vincenzo Dattilo
- Department of "Scienze della Salute", University "Magna Graecia" of Catanzaro, Viale Europa, Catanzaro
| | - Giada Catalogna
- Department of "Scienze della Salute", University "Magna Graecia" of Catanzaro, Viale Europa, Catanzaro
| | - Domenica Scumaci
- Department of "Medicina Sperimentale e Clinica", University "Magna Graecia" of Catanzaro, Viale Europa, Catanzaro
| | - Claudia Vincenza Fiumara
- Department of "Medicina Sperimentale e Clinica", University "Magna Graecia" of Catanzaro, Viale Europa, Catanzaro
| | | | - Giuseppe Perrotti
- Department of "Scienze della Salute", University "Magna Graecia" of Catanzaro, Viale Europa, Catanzaro
| | | | - Rossana Tallerico
- Department of "Scienze della Salute", University "Magna Graecia" of Catanzaro, Viale Europa, Catanzaro
| | - Cristina B Spoleti
- Department of "Scienze della Salute", University "Magna Graecia" of Catanzaro, Viale Europa, Catanzaro
| | - Nicola Costa
- Department of "Scienze della Salute", University "Magna Graecia" of Catanzaro, Viale Europa, Catanzaro
| | - Rodolfo Iuliano
- Department of "Scienze della Salute", University "Magna Graecia" of Catanzaro, Viale Europa, Catanzaro
| | - Giovanni Cuda
- Department of "Medicina Sperimentale e Clinica", University "Magna Graecia" of Catanzaro, Viale Europa, Catanzaro
| | - Rosario Amato
- Department of "Scienze della Salute", University "Magna Graecia" of Catanzaro, Viale Europa, Catanzaro.
| | - Nicola Perrotti
- Department of "Scienze della Salute", University "Magna Graecia" of Catanzaro, Viale Europa, Catanzaro.
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60
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Hesam Shariati MB, Seghinsara AM, Shokrzadeh N, Niknafs B. The effect of fludrocortisone on the uterine receptivity partially mediated by ERK1/2-mTOR pathway. J Cell Physiol 2019; 234:20098-20110. [PMID: 30968418 DOI: 10.1002/jcp.28609] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 03/10/2019] [Accepted: 03/19/2019] [Indexed: 12/13/2022]
Abstract
Implantation of embryos needs endometrial receptivity. Mineralocorticoids is one of the causes influencing the implantation window. This study targeted to evaluation fludrocortisone different properties on endometrial receptivity. The objective of this study was to assess whether treatment with fludrocortisone could impact the expression of diverse genes and proteins that are involved in uterine receptivity in mice. In this study, 40 female adult BALB/c mice were used. The samples were allocated to four groups of ten. Control group (C) received: vehicle; fludrocortisone group (FCA): received 1.5 mg/kg fludrocortisone; PP242 group (PP242): received 30 mg/kg PP242; fludrocortisone+PP242 group (FCA+PP242): received fludrocortisone and PP242. Mice were killed on window implantation day after mating and confirmed pregnancy. The endometrial epithelium of mouse was collected to assess mRNA expression of leukemia inhibitory factor (LIF), mucin-1 (MUC1), heparin-binding epidermal growth factor (HB-EGF), (Msx.1), miRNA Let-7a, and miRNA 223-3p as well as protein expression of extracellular signal-regulated kinase 1/2 (ERK1/2), mammalian target of rapamycin (mTOR), and eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) in the uterine using real-time PCR and western blot, respectively. In comparison with the control group, fludrocortisone administration upregulated the expression of LIF, HB-EGF, Msx.1, miRNA Let-7a, ERK1/2, and mTOR in the epithelial endometrium. The PP242-treated group demonstrated a significant rise in the expression of MUC1, miRNA 223-3p and a remarkable decline in ERK1/2 and p-4E-BP1 levels in comparison with the control group. Combination therapy of (FCA+PP242) resulted in a remarkable rise in LIF, Msx-1, HB-EGF, ERK1/2, and mTOR levels, in comparison with the PP242 group. Furthermore, combination therapy of (FCA+PP242) downregulated the expression of MUC1 in comparison with the PP242-treated group. According to the results, fludrocortisone affected uterine receptivity possibly by means of modulating the expression of genes involved in the uterine receptivity and activation of the ERK1/2-mTOR pathway.
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Affiliation(s)
| | - Abbas Majdi Seghinsara
- Department of Anatomical Sciences, Faculty of Medicine, Tabriz University of Medical Science, Tabriz, Iran
| | - Naser Shokrzadeh
- Infertility and Reproductive Health research center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran
| | - Behrooz Niknafs
- Department of Reproductive Biology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Science, Tabriz, Iran
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61
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Swanson EA, Nelson JW, Jeng S, Erspamer KJ, Yang CL, McWeeney S, Ellison DH. Salt-sensitive transcriptome of isolated kidney distal tubule cells. Physiol Genomics 2019; 51:125-135. [PMID: 30875275 DOI: 10.1152/physiolgenomics.00119.2018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
In the distal kidney tubule, the steroid hormone aldosterone regulates sodium reabsorption via the epithelial sodium channel (ENaC). Most studies seeking to identify ENaC-regulating aldosterone-induced proteins have used transcriptional profiling of cultured cells. To identify salt-sensitive transcripts in an in vivo model, we used low-NaCl or high-NaCl diet to stimulate or suppress endogenous aldosterone, in combination with magnetic- and fluorescence-activated cell sorting to isolate distal tubule cells from mouse kidney for transcriptional profiling. Of the differentially expressed transcripts, 162 were more abundant in distal tubule cells isolated from mice fed low-NaCl diet, and 161 were more abundant in distal tubule cells isolated from mice fed high-NaCl diet. Enrichment analysis of Gene Ontology biological process terms identified multiple statistically overrepresented pathways among the differentially expressed transcripts that were more abundant in distal tubule cells isolated from mice fed low-NaCl diet, including ion transmembrane transport, regulation of growth, and negative regulation of apoptosis. Analysis of Gene Ontology molecular function terms identified differentially expressed transcription factors, transmembrane transporters, kinases, and G protein-coupled receptors. Finally, comparison with a recently published study of gene expression changes in distal tubule cells in response to administration of aldosterone identified 18 differentially expressed genes in common between the two experiments. When expression of these genes was measured in cortical collecting ducts microdissected from mice fed low-NaCl or high-NaCl diet, eight were differentially expressed. These genes are likely to be regulated directly by aldosterone and may provide insight into aldosterone signaling to ENaC in the distal tubule.
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Affiliation(s)
- Elizabeth A Swanson
- Division of Nephrology and Hypertension, Department of Medicine, Oregon Health & Science University , Portland, Oregon
| | - Jonathan W Nelson
- Division of Nephrology and Hypertension, Department of Medicine, Oregon Health & Science University , Portland, Oregon
| | - Sophia Jeng
- Division of Bioinformatics & Computational Biology, Department of Medical Informatics and Clinical Epidemiology, Oregon Health & Science University , Portland, Oregon
| | - Kayla J Erspamer
- Division of Nephrology and Hypertension, Department of Medicine, Oregon Health & Science University , Portland, Oregon
| | - Chao-Ling Yang
- Division of Nephrology and Hypertension, Department of Medicine, Oregon Health & Science University , Portland, Oregon
| | - Shannon McWeeney
- Division of Bioinformatics & Computational Biology, Department of Medical Informatics and Clinical Epidemiology, Oregon Health & Science University , Portland, Oregon.,Oregon Clinical & Translational Research Institute, Oregon Health & Science University , Portland, Oregon
| | - David H Ellison
- Division of Nephrology and Hypertension, Department of Medicine, Oregon Health & Science University , Portland, Oregon.,Oregon Clinical & Translational Research Institute, Oregon Health & Science University , Portland, Oregon.,Renal Section, Portland VA Medical Center , Portland, Oregon
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62
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Wang H, Zhang J, You G. The mechanistic links between insulin and human organic anion transporter 4. Int J Pharm 2019; 555:165-174. [PMID: 30453017 DOI: 10.1016/j.ijpharm.2018.11.040] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 11/10/2018] [Accepted: 11/15/2018] [Indexed: 11/18/2022]
Abstract
Human organic anion transporter 4 (hOAT4) belongs to a class of organic anion transporters that exert critical function in the secretion, absorption, and distribution of numerous drugs in the body, such as anti-viral drugs, anti-cancer therapeutics, antibiotics, antihypertensive medicine, and anti-inflammatory drugs. hOAT4 is richly existent in the kidney and placenta. We previously established that serum- and glucocorticoid-inducible kinases (sgk) stimulate hOAT4 expression and transport activity by abrogating the inhibitory effect of a ubiquitin ligase Nedd4-2. Insulin is one of the upstream signaling molecules for sgk. We therefore investigated the effect of insulin on hOAT4 function. We showed that insulin stimulated hOAT4 expression and transport activity, and the action of insulin was abolished in cells overexpressing Nedd4-2-specific siRNA to knockdown the endogenous Nedd4-2. We further showed that insulin phosphorylated serine 327 on Nedd4-2 and weakened the interaction between hOAT4 and Nedd4-2. Interestingly, in cells overexpressing sgk2, the stimulatory effect of insulin on hOAT4 was diminished. In addition, the stimulatory effect of insulin on hOAT4 was blocked by wortmannin and buparlisib, two PI3K inhibitors. In conclusion, our study demonstrated that insulin stimulates hOAT4 expression and transport activity by abrogating the inhibition effect of Nedd4-2 on the transporter. Moreover, insulin regulates hOAT4 by competing with sgk2 rather than through sgk2.
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Affiliation(s)
- Haoxun Wang
- Department of Pharmaceutics, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Jinghui Zhang
- Department of Pharmaceutics, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Guofeng You
- Department of Pharmaceutics, Rutgers, The State University of New Jersey, Piscataway, NJ, USA.
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63
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Abstract
Aldosterone was characterized as the major mineralocorticoid hormone 65 years ago, and since then its physiologic role in epidural electrolyte homeostasis the province of nephrologists. In epithelia it acts via the mineralocorticoid receptor (MR) to retain Na+ and excrete K+; MRs, however, are widely expressed in organs not known to be aldosterone target tissues. MRs are not merely "aldosterone receptors," as they have equivalently high affinity for the physiologic glucocorticoids, and for progesterone. In epithelia (plus in the blood vessel wall and in the nucleus tractus solitarius of the brain) MRs are "protected" by coexpression of the enzyme 11β-hydroxysteroid dehydrogenase. This enzyme converts cortisol-which circulates at much higher concentrations than aldosterone-to receptor-inactive cortisone, thus allowing aldosterone selectively to activate "protected" MR. In tissues which do not express 11β-hydroxysteroid dehydrogenase, the default MR ligand is cortisol, which circulates at ≥100-fold higher plasma free concentrations than aldosterone. In such tissues there is as yet scant evidence for the physiologic role of cortisol-occupied MR: over the past decade, however, it has become clear that in damaged tissues cortisol can act as an MR-agonist, mimicking the effects seen with aldosterone under experimental conditions, in vitro and in vivo. Many pathophysiologic roles have been attributed to aldosterone: on the current evidence there are none outside its long established epithelial actions, those on the blood vessel wall and on the nucleus tractus solitarius.
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Affiliation(s)
- John W Funder
- Hudson Institute and Monash University, Monash Health, Clayton, VIC, Australia.
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64
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Kamel KS, Schreiber M, Halperin ML. Renal potassium physiology: integration of the renal response to dietary potassium depletion. Kidney Int 2018; 93:41-53. [PMID: 29102372 DOI: 10.1016/j.kint.2017.08.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 07/31/2017] [Accepted: 08/03/2017] [Indexed: 01/30/2023]
Abstract
We summarize the current understanding of the physiology of the renal handling of potassium (K+), and present an integrative view of the renal response to K+ depletion caused by dietary K+ restriction. This renal response involves contributions from different nephron segments, and aims to diminish the rate of excretion of K+ as a result of: decreasing the rate of electrogenic (and increasing the rate of electroneutral) reabsorption of sodium in the aldosterone-sensitive distal nephron (ASDN), decreasing the abundance of renal outer medullary K+ channels in the luminal membrane of principal cells in the ASDN, decreasing the flow rate in the ASDN, and increasing the reabsorption of K+ in the cortical and medullary collecting ducts. The implications of this physiology for the association between K+ depletion and hypertension, and K+ depletion and formation of calcium kidney stones are discussed.
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Affiliation(s)
- Kamel S Kamel
- Renal Division, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada; Keenan Research Center, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada.
| | - Martin Schreiber
- Renal Division, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Mitchell L Halperin
- Renal Division, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada; Keenan Research Center, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada
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65
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Abstract
Since its discovery, aldosterone and ion modulation have been entwined. While scientific investigations throughout the decades have emphasized aldosterone's connection to Na+, K+, and H+ homeostasis, more recent research has demonstrated a relationship between aldosterone and Mg2+, Ca2+, and Cl- homeostasis. The mechanisms connecting aldosterone to ion regulation frequently involve ion channels; the membrane localized proteins containing at least one aqueous pore for ion conduction. In order to precisely control intracellular or intraorganelle ion concentrations, ion channels have evolved highly specific regions within the conduction pore that select ions by charge, size, and/or dehydration energy requirement, meaning aldosterone must be able to modulate multiple ion channels to regulate the many ions described above. The list of ion channels presently connected to aldosterone includes ENaC (Na+), ROMK/BK (K+), TRPV4/5/6 (Ca2+), TRPM7/6 (Mg2+), and ClC-K/CFTR (Cl-), among others. This list is only expected to grow over time, as the promiscuity of aldosterone becomes more understood.
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Affiliation(s)
| | - Rhian M Touyz
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Alvin Shrier
- Department of Physiology, McGill University, Montreal, QC, Canada.
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66
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Brinks J, van Dijk EHC, Habeeb M, Nikolaou A, Tsonaka R, Peters HAB, Sips HCM, van de Merbel AF, de Jong EK, Notenboom RGE, Kielbasa SM, van der Maarel SM, Quax PHA, Meijer OC, Boon CJF. The Effect of Corticosteroids on Human Choroidal Endothelial Cells: A Model to Study Central Serous Chorioretinopathy. ACTA ACUST UNITED AC 2018; 59:5682-5692. [DOI: 10.1167/iovs.18-25054] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Joost Brinks
- Department of Ophthalmology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Elon H. C. van Dijk
- Department of Ophthalmology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Mahmoud Habeeb
- Department of Ophthalmology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Aikaterini Nikolaou
- Department of Ophthalmology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Roula Tsonaka
- Department of Medical Statistics and Bioinformatics, Leiden University Medical Centre, Leiden, The Netherlands
| | - Hendrika A. B. Peters
- Department of Vascular Surgery, Leiden University Medical Centre, Leiden, The Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Centre, Leiden, The Netherlands
| | - Hetty C. M. Sips
- Department of Medicine, Division of Endocrinology and Metabolism, Leiden University Medical Centre, Leiden, The Netherlands
| | | | - Eiko K. de Jong
- Department of Ophthalmology, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Robbert G. E. Notenboom
- Department of Anatomy and Embryology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Szymon M. Kielbasa
- Department of Medical Statistics and Bioinformatics, Leiden University Medical Centre, Leiden, The Netherlands
| | | | - Paul H. A. Quax
- Department of Vascular Surgery, Leiden University Medical Centre, Leiden, The Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Centre, Leiden, The Netherlands
| | - Onno C. Meijer
- Department of Medicine, Division of Endocrinology and Metabolism, Leiden University Medical Centre, Leiden, The Netherlands
| | - Camiel J. F. Boon
- Department of Ophthalmology, Leiden University Medical Centre, Leiden, The Netherlands
- Department of Ophthalmology, Academic Medical Centre, University of Amsterdam, The Netherlands
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67
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Haas JG, Weber J, Gonzalez O, Zimmer R, Griffiths SJ. Antiviral activity of the mineralocorticoid receptor NR3C2 against Herpes simplex virus Type 1 (HSV-1) infection. Sci Rep 2018; 8:15876. [PMID: 30367157 PMCID: PMC6203759 DOI: 10.1038/s41598-018-34241-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 10/11/2018] [Indexed: 01/23/2023] Open
Abstract
Analysis of a genome-scale RNA interference screen of host factors affecting herpes simplex virus type 1 (HSV-1) revealed that the mineralocorticoid receptor (MR) inhibits HSV-1 replication. As a ligand-activated transcription factor the MR regulates sodium transport and blood pressure in the kidney in response to aldosterone, but roles have recently been elucidated for the MR in other cellular processes. Here, we show that the MR and other members of the mineralocorticoid signalling pathway including HSP90 and FKBP4, possess anti-viral activity against HSV-1 independent of their effect on sodium transport, as shown by sodium channel inhibitors. Expression of the MR is upregulated upon infection in an interferon (IFN) and viral transcriptional activator VP16-dependent fashion. Furthermore, the MR and VP16, together with the cellular co-activator Oct-1, transactivate the hormone response element (HRE) present in the MR promoter and those of its transcriptional targets. As the MR induces IFN expression, our data suggests the MR is involved in a positive feedback loop that controls HSV-1 infection.
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Affiliation(s)
- Jürgen G Haas
- Division of Infection and Pathway Medicine, University of Edinburgh, Edinburgh, EH16 4SB, UK
| | - Julia Weber
- Division of Infection and Pathway Medicine, University of Edinburgh, Edinburgh, EH16 4SB, UK
| | - Orland Gonzalez
- Institute for Informatics, Ludwig-Maximilians Universität München, 80333, München, Germany
| | - Ralf Zimmer
- Institute for Informatics, Ludwig-Maximilians Universität München, 80333, München, Germany
| | - Samantha J Griffiths
- Division of Infection and Pathway Medicine, University of Edinburgh, Edinburgh, EH16 4SB, UK.
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68
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Meijer OC, Buurstede JC, Schaaf MJM. Corticosteroid Receptors in the Brain: Transcriptional Mechanisms for Specificity and Context-Dependent Effects. Cell Mol Neurobiol 2018; 39:539-549. [PMID: 30291573 PMCID: PMC6469829 DOI: 10.1007/s10571-018-0625-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 09/25/2018] [Indexed: 12/22/2022]
Abstract
Corticosteroid hormones act in the brain to support adaptation to stress via binding to mineralocorticoid and glucocorticoid receptors (MR and GR). These receptors act in large measure as transcription factors. Corticosteroid effects can be highly divergent, depending on the receptor type, but also on brain region, cell type, and physiological context. These differences ultimately depend on differential interactions of MR and GR with other proteins, which determine ligand binding, nuclear translocation, and transcriptional activities. In this review, we discuss established and potential mechanisms that confer receptor and cell type-specific effects of the MR and GR-mediated transcriptional effects in the brain.
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Affiliation(s)
- Onno C Meijer
- Division of Endocrinology, Department of Medicine, Leiden University Medical Center, 2333 ZA, Leiden, The Netherlands. .,Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, 2333 ZA, Leiden, The Netherlands.
| | - J C Buurstede
- Division of Endocrinology, Department of Medicine, Leiden University Medical Center, 2333 ZA, Leiden, The Netherlands.,Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, 2333 ZA, Leiden, The Netherlands
| | - Marcel J M Schaaf
- Department of Animal Sciences and Health (M.J.M.S.), Institute of Biology, Leiden University, 2333 CC, Leiden, The Netherlands
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69
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Ware AW, Cheung TT, Rasulov S, Burstein E, McDonald FJ. Epithelial Na + Channel: Reciprocal Control by COMMD10 and Nedd4-2. Front Physiol 2018; 9:793. [PMID: 29997525 PMCID: PMC6028986 DOI: 10.3389/fphys.2018.00793] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 06/06/2018] [Indexed: 11/25/2022] Open
Abstract
Optimal function of the epithelial sodium channel (ENaC) in the distal nephron is key to the kidney’s long-term control of salt homeostasis and blood pressure. Multiple pathways alter ENaC cell surface populations, including correct processing and trafficking in the secretory pathway to the cell surface, and retrieval from the cell surface through ubiquitination by the ubiquitin ligase Nedd4-2, clathrin-mediated endocytosis, and sorting in the endosomal system. Members of the Copper Metabolism Murr1 Domain containing (COMMD) family of 10 proteins are known to interact with ENaC. COMMD1, 3 and 9 have been shown to down-regulate ENaC, most likely through Nedd4-2, however, the other COMMD family members remain uncharacterized. To investigate the effects of the COMMD10 protein on ENaC trafficking and function, the interaction of ENaC and COMMD10 was confirmed. Stable COMMD10 knockdown in Fischer rat thyroid epithelia decreased ENaC current and this decreased current was associated with increased Nedd4-2 protein, a known negative regulator of ENaC. However, inhibition of Nedd4-2’s ubiquitination of ENaC was only able to partially rescue the observed reduction in current. Stable COMMD10 knockdown results in defects both in endocytosis and recycling of transferrin suggesting COMMD10 likely interacts with multiple pathways to regulate ENaC and therefore could be involved in the long-term control of blood pressure.
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Affiliation(s)
- Adam W Ware
- Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Tanya T Cheung
- Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Sahib Rasulov
- Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Ezra Burstein
- Department of Internal Medicine and Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Fiona J McDonald
- Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
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70
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de Kloet ER, Meijer OC, de Nicola AF, de Rijk RH, Joëls M. Importance of the brain corticosteroid receptor balance in metaplasticity, cognitive performance and neuro-inflammation. Front Neuroendocrinol 2018; 49:124-145. [PMID: 29428549 DOI: 10.1016/j.yfrne.2018.02.003] [Citation(s) in RCA: 154] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 01/25/2018] [Accepted: 02/07/2018] [Indexed: 01/14/2023]
Abstract
Bruce McEwen's discovery of receptors for corticosterone in the rat hippocampus introduced higher brain circuits in the neuroendocrinology of stress. Subsequently, these receptors were identified as mineralocorticoid receptors (MRs) that are involved in appraisal processes, choice of coping style, encoding and retrieval. The MR-mediated actions on cognition are complemented by slower actions via glucocorticoid receptors (GRs) on contextualization, rationalization and memory storage of the experience. These sequential phases in cognitive performance depend on synaptic metaplasticity that is regulated by coordinate MR- and GR activation. The receptor activation includes recruitment of coregulators and transcription factors as determinants of context-dependent specificity in steroid action; they can be modulated by genetic variation and (early) experience. Interestingly, inflammatory responses to damage seem to be governed by a similarly balanced MR:GR-mediated action as the initiating, terminating and priming mechanisms involved in stress-adaptation. We conclude with five questions challenging the MR:GR balance hypothesis.
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Affiliation(s)
- E R de Kloet
- Division of Endocrinology, Department of Internal Medicine, Leiden University Medical Center, Leiden, The Netherlands.
| | - O C Meijer
- Division of Endocrinology, Department of Internal Medicine, Leiden University Medical Center, Leiden, The Netherlands.
| | - A F de Nicola
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biologia y Medicina Experimental, Buenos Aires, Argentina.
| | - R H de Rijk
- Department of Psychiatry, Leiden University Medical Center, Leiden, The Netherlands & Department of Clinical Psychology, Leiden University, The Netherlands.
| | - M Joëls
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, The Netherlands; University of Groningen, University Medical Center Groningen, The Netherlands.
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71
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Yang G, Pillich H, White R, Czikora I, Pochic I, Yue Q, Hudel M, Gorshkov B, Verin A, Sridhar S, Isales CM, Eaton DC, Hamacher J, Chakraborty T, Lucas R. Listeriolysin O Causes ENaC Dysfunction in Human Airway Epithelial Cells. Toxins (Basel) 2018; 10:toxins10020079. [PMID: 29439494 PMCID: PMC5848180 DOI: 10.3390/toxins10020079] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/01/2018] [Accepted: 02/07/2018] [Indexed: 01/22/2023] Open
Abstract
Pulmonary permeability edema is characterized by reduced alveolar Na⁺ uptake capacity and capillary barrier dysfunction and is a potentially lethal complication of listeriosis. Apical Na⁺ uptake is mainly mediated by the epithelial sodium channel (ENaC) and initiates alveolar liquid clearance. Here we examine how listeriolysin O (LLO), the pore-forming toxin of Listeria monocytogenes, impairs the expression and activity of ENaC. To that purpose, we studied how sub-lytic concentrations of LLO affect negative and positive regulators of ENaC expression in the H441 airway epithelial cell line. LLO reduced expression of the crucial ENaC-α subunit in H441 cells within 2 h and this was preceded by activation of PKC-α, a negative regulator of the channel's expression. At later time points, LLO caused a significant reduction in the phosphorylation of Sgk-1 at residue T256 and of Akt-1 at residue S473, both of which are required for full activation of ENaC. The TNF-derived TIP peptide prevented LLO-mediated PKC-α activation and restored phospho-Sgk-1-T256. The TIP peptide also counteracted the observed LLO-induced decrease in amiloride-sensitive Na⁺ current and ENaC-α expression in H441 cells. Intratracheally instilled LLO caused profound pulmonary edema formation in mice, an effect that was prevented by the TIP peptide; thus indicating the therapeutic potential of the peptide for the treatment of pore-forming toxin-associated permeability edema.
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Affiliation(s)
- Guang Yang
- Vascular Biology Center, Medical College of Georgia at Augusta University, Room CB-3213B, Augusta, GA 30912-2500, USA.
| | - Helena Pillich
- Institute of Medical Microbiology, Justus-Liebig University Giessen, 35392 Gießen, Germany.
| | - Richard White
- Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Room CB-3213B, Augusta, GA 30912-2500, USA.
- Department of Biomedical Sciences, Georgia Campus-Philadelphia College of Osteopathic Medicine, Atlanta, GA 30224, USA.
| | - Istvan Czikora
- Vascular Biology Center, Medical College of Georgia at Augusta University, Room CB-3213B, Augusta, GA 30912-2500, USA.
| | - Isabelle Pochic
- Biochemical Pharmacology, University of Konstanz, 78464 Konstanz, Germany.
- Sandoz Inc., 83607 Holzkirchen, Germany.
| | - Qiang Yue
- Department of Physiology, Emory School of Medicine, Atlanta, GA 30307, USA.
| | - Martina Hudel
- Institute of Medical Microbiology, Justus-Liebig University Giessen, 35392 Gießen, Germany.
| | - Boris Gorshkov
- Vascular Biology Center, Medical College of Georgia at Augusta University, Room CB-3213B, Augusta, GA 30912-2500, USA.
| | - Alexander Verin
- Vascular Biology Center, Medical College of Georgia at Augusta University, Room CB-3213B, Augusta, GA 30912-2500, USA.
| | - Supriya Sridhar
- Vascular Biology Center, Medical College of Georgia at Augusta University, Room CB-3213B, Augusta, GA 30912-2500, USA.
| | - Carlos M Isales
- Department of Medicine, Medical College of Georgia, Augusta, GA 30901, USA.
| | - Douglas C Eaton
- Department of Physiology, Emory School of Medicine, Atlanta, GA 30307, USA.
| | - Jürg Hamacher
- Biochemical Pharmacology, University of Konstanz, 78464 Konstanz, Germany.
- Department of Pneumology, Lindenhofspital, 3001 Bern, Switzerland.
- Internal, Pulmonary and Critical Care Medicine, Saarland University, 66424 Homburg/Saar, Germany.
- Lungen-und Atmungsstifung, 3001 Bern, Switzerland.
| | - Trinad Chakraborty
- Institute of Medical Microbiology, Justus-Liebig University Giessen, 35392 Gießen, Germany.
| | - Rudolf Lucas
- Vascular Biology Center, Medical College of Georgia at Augusta University, Room CB-3213B, Augusta, GA 30912-2500, USA.
- Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Room CB-3213B, Augusta, GA 30912-2500, USA.
- Department of Medicine, Medical College of Georgia, Augusta, GA 30901, USA.
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72
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Wang H, Liu C, You G. The activity of organic anion transporter-3: Role of dexamethasone. J Pharmacol Sci 2018; 136:79-85. [PMID: 29422382 DOI: 10.1016/j.jphs.2017.12.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 12/18/2017] [Accepted: 12/28/2017] [Indexed: 12/14/2022] Open
Abstract
Human organic anion transporter-3 (hOAT3) is richly expressed in the kidney, where it plays critical roles in the secretion, from the blood to urine, of clinically important drugs, such as anti-viral therapeutics, anti-cancer drugs, antibiotics, antihypertensives, and anti-inflammatories. In the current study, we examined the role of dexamethasone in hOAT3 transport activity in the kidney HEK293 cells. Cis-inhibition study showed that dexamethasone exhibited a concentration-dependent inhibition of hOAT3-mediated uptake of estrone sulfate, a prototypical substrate for the transporter, with IC50 value of 49.91 μM. Dixon plot analysis revealed that inhibition by dexamethasone was competitive with a Ki = 47.08 μM. In contrast to the cis-inhibition effect of dexamethasone, prolonged incubation (6 h) of hOAT3-expressing cells with dexamethasone resulted in an upregulation of hOAT3 expression and transport activity, kinetically revealed as an increase in the maximum transport velocity Vmax without meaningful alteration in substrate-binding affinity Km. Such upregulation was abrogated by GSK650394, a specific inhibitor for serum- and glucocorticoid-inducible kinases (sgk). Dexamethasone also enhanced sgk1 phosphorylation. Our study demonstrated that dexamethasone exhibits dual effects on hOAT3: it is a competitive inhibitor for hOAT3-mediated transport, and interestingly, when entering the cells, it stimulates hOAT3 expression and transport activity through sgk1.
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Affiliation(s)
- Haoxun Wang
- Department of Pharmaceutics, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | - Chenchang Liu
- Department of Pharmaceutics, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | - Guofeng You
- Department of Pharmaceutics, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA.
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73
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Aldosterone, SGK1, and ion channels in the kidney. Clin Sci (Lond) 2018; 132:173-183. [PMID: 29352074 PMCID: PMC5817097 DOI: 10.1042/cs20171525] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 12/15/2017] [Accepted: 12/19/2017] [Indexed: 12/14/2022]
Abstract
Hyperaldosteronism, a common cause of hypertension, is strongly connected to Na+, K+, and Mg2+ dysregulation. Owing to its steroidal structure, aldosterone is an active transcriptional modifier when bound to the mineralocorticoid receptor (MR) in cells expressing the enzyme 11β-hydroxysteroid dehydrogenase 2, such as those comprising the aldosterone-sensitive distal nephron (ASDN). One such up-regulated protein, the ubiquitous serum and glucocorticoid regulated kinase 1 (SGK1), has the capacity to modulate the surface expression and function of many classes of renal ion channels, including those that transport Na+ (ENaC), K+ (ROMK/BK), Ca2+ (TRPV4/5/6), Mg2+ (TRPM7/6), and Cl− (ClC-K, CFTR). Here, we discuss the mechanisms by which ASDN expressed channels are up-regulated by SGK1, while highlighting newly discovered pathways connecting aldosterone to nonselective cation channels that are permeable to Mg2+ (TRPM7) or Ca2+ (TRPV4).
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74
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Heat acclimation causes a linear decrease in sweat sodium ion concentration. J Therm Biol 2018; 71:237-240. [DOI: 10.1016/j.jtherbio.2017.12.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 11/27/2017] [Accepted: 12/06/2017] [Indexed: 11/18/2022]
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75
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Inhibitors of the proteasome stimulate the epithelial sodium channel (ENaC) through SGK1 and mimic the effect of aldosterone. Pflugers Arch 2017; 470:295-304. [DOI: 10.1007/s00424-017-2060-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 08/17/2017] [Accepted: 08/21/2017] [Indexed: 10/19/2022]
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76
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Wang H, You G. SGK1/Nedd4-2 signaling pathway regulates the activity of human organic anion transporters 3. Biopharm Drug Dispos 2017; 38:449-457. [PMID: 28608480 DOI: 10.1002/bdd.2085] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 06/06/2017] [Accepted: 06/07/2017] [Indexed: 01/11/2023]
Abstract
Human organic anion transporter 3 (hOAT3) is localized at the basolateral membrane of renal proximal tubule cells and facilitates the renal secretion of numerous clinical drugs, including anti-HIV therapeutics, anti-tumor drugs, antibiotics, antihypertension drugs and anti-inflammatories. The present study explored the role of serum and glucocorticoid-inducible kinase 1 (sgk1) in the regulation of hOAT3. It was shown that over-expression of sgk1 in hOAT3-expressing cells stimulated hOAT3 transport activity by enhancing the transporter expression at the plasma membrane, kinetically reflected as an increased maximal transport velocity Vmax without substantial change in the substrate-binding affinity Km . In contrast, treatment of cells with the sgk-specific inhibitor GSK650394 resulted in a dose-dependent inhibition of hOAT3 transport activity. Evidence was further provided that sgk1 regulation of hOAT3 activity was mediated by ubiquitin ligase Nedd4-2, an enzyme previously shown to have an inhibitory effect on hOAT3. It was shown that sgk1 phosphorylated Nedd4-2, weakened the association between Nedd4-2 and hOAT3, and decreased hOAT3 ubiquitination. Functionally, the sgk1-stimulated hOAT3 transport activity was attenuated in the presence of a ligase-dead mutant of Nedd4-2. In summary, the investigation established for the first time that sgk1 stimulates hOAT3 transport activity by interfering with the inhibitory effect of Nedd4-2 on the transporter.
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Affiliation(s)
- Haoxun Wang
- Rutgers The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Guofeng You
- Rutgers The State University of New Jersey, Piscataway, NJ, 08854, USA
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77
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Wynne BM, Zou L, Linck V, Hoover RS, Ma HP, Eaton DC. Regulation of Lung Epithelial Sodium Channels by Cytokines and Chemokines. Front Immunol 2017; 8:766. [PMID: 28791006 PMCID: PMC5524836 DOI: 10.3389/fimmu.2017.00766] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Accepted: 06/16/2017] [Indexed: 12/20/2022] Open
Abstract
Acute lung injury leading to acute respiratory distress (ARDS) is a global health concern. ARDS patients have significant pulmonary inflammation leading to flooding of the pulmonary alveoli. This prevents normal gas exchange with consequent hypoxemia and causes mortality. A thin fluid layer in the alveoli is normal. The maintenance of this thin layer results from fluid movement out of the pulmonary capillaries into the alveolar interstitium driven by vascular hydrostatic pressure and then through alveolar tight junctions. This is then balanced by fluid reabsorption from the alveolar space mediated by transepithelial salt and water transport through alveolar cells. Reabsorption is a two-step process: first, sodium enters via sodium-permeable channels in the apical membranes of alveolar type 1 and 2 cells followed by active extrusion of sodium into the interstitium by the basolateral Na+, K+-ATPase. Anions follow the cationic charge gradient and water follows the salt-induced osmotic gradient. The proximate cause of alveolar flooding is the result of a failure to reabsorb sufficient salt and water or a failure of the tight junctions to prevent excessive movement of fluid from the interstitium to alveolar lumen. Cytokine- and chemokine-induced inflammation can have a particularly profound effect on lung sodium transport since they can alter both ion channel and barrier function. Cytokines and chemokines affect alveolar amiloride-sensitive epithelial sodium channels (ENaCs), which play a crucial role in sodium transport and fluid reabsorption in the lung. This review discusses the regulation of ENaC via local and systemic cytokines during inflammatory disease and the effect on lung fluid balance.
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Affiliation(s)
- Brandi M Wynne
- Department of Medicine, Nephrology, Emory University, Atlanta, GA, United States.,Department of Physiology, Emory University, Atlanta, GA, United States.,The Center for Cell and Molecular Signaling, Emory University, Atlanta, GA, United States
| | - Li Zou
- Department of Physiology, Emory University, Atlanta, GA, United States
| | - Valerie Linck
- Department of Physiology, Emory University, Atlanta, GA, United States
| | - Robert S Hoover
- Department of Medicine, Nephrology, Emory University, Atlanta, GA, United States.,Department of Physiology, Emory University, Atlanta, GA, United States.,Research Service, Atlanta Veteran's Administration Medical Center, Decatur, GA, United States
| | - He-Ping Ma
- Department of Physiology, Emory University, Atlanta, GA, United States.,The Center for Cell and Molecular Signaling, Emory University, Atlanta, GA, United States
| | - Douglas C Eaton
- Department of Physiology, Emory University, Atlanta, GA, United States.,The Center for Cell and Molecular Signaling, Emory University, Atlanta, GA, United States
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78
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Kim SM, Kang JO, Lim JE, Hwang SY, Oh B. Csk Regulates Blood Pressure by Controlling the Synthetic Pathways of Aldosterone. Circ J 2017; 82:168-175. [PMID: 28724838 DOI: 10.1253/circj.cj-17-0080] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Blood pressure is regulated by a network of diverse physiological pathways. The C-terminal Src kinase (CSK) locus (15q24) is associated with blood pressure in various ethnic groups. It was recently reported thatCskinsufficiency increases blood pressure through Src. The mechanisms of hypertension inCsk+/-mice are examined further in this study.Methods and Results:To identify a causal component responsible for hypertension inCsk+/-, the heart rate was measured by electrocardiogram and plasma volume by Evans blue dilution. Plasma volume increased inCsk+/-compared with wild-types, while the heart rate did not change. Plasma sodium and aldosterone levels rose consistently inCsk+/-vs. wild-types, and spironolactone, a mineralocorticoid receptor antagonist, reduced blood pressure. The amounts of Sgk1 and Na+/K+-ATPase (NKA) increased in the kidney ofCsk+/-compared with wild-types. It was also found that Cyp11b2 (aldosterone synthase) was upregulated in the adrenal glands ofCsk+/-, and that Csk was enriched in the zona glomerulosa of adrenals, the major site of aldosterone production in the normal mouse. CONCLUSIONS The results of the present study identify a physiological pathway by which blood pressure is regulated, in which the insufficiency ofCskinduces aldosterone production with zonal specificity in the adrenal glands, increasing sodium reabsorption and plasma volume and thus resulting in hypertension.
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Affiliation(s)
- Sung-Moon Kim
- Department of Animal Biotechnology, Graduate School of Future Convergence Technology, Hankyong National University
| | - Ji-One Kang
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University
| | - Ji Eun Lim
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University
| | - Sue-Yun Hwang
- Department of Chemical Engineering, College of Engineering, Hankyong National University
| | - Bermseok Oh
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University
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79
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Erben RG, Andrukhova O. FGF23-Klotho signaling axis in the kidney. Bone 2017; 100:62-68. [PMID: 27622885 DOI: 10.1016/j.bone.2016.09.010] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Revised: 09/08/2016] [Accepted: 09/09/2016] [Indexed: 01/04/2023]
Abstract
Fibroblast growth factor-23 (FGF23) is a bone-derived hormone protecting against the potentially deleterious effects of hyperphosphatemia by suppression of phosphate reabsorption and of active vitamin D hormone synthesis in the kidney. The kidney is one of the main target organs of FGF23 signaling. The purpose of this review is to highlight the recent advances in the area of FGF23-Klotho signaling in the kidney. During recent years, it has become clear that FGF23 acts independently on proximal and distal tubular epithelium. In proximal renal tubules, FGF23 suppresses phosphate reabsorption by a Klotho dependent activation of extracellular signal-regulated kinase-1/2 (ERK1/2) and of serum/glucocorticoid-regulated kinase-1 (SGK1), leading to phosphorylation of the scaffolding protein Na+/H+ exchange regulatory cofactor (NHERF)-1 and subsequent internalization and degradation of sodium-phosphate cotransporters. In distal renal tubules, FGF23 augments calcium and sodium reabsorption by increasing the apical membrane expression of the epithelial calcium channel TRPV5 and of the sodium-chloride cotransporter NCC through a Klotho dependent activation of with-no-lysine kinase-4 (WNK4). In proximal and distal renal tubules, FGF receptor-1 is probably the dominant FGF receptor mediating the effects of FGF23 by forming a complex with membrane-bound Klotho in the basolateral membrane. The newly described sodium- and calcium-conserving functions of FGF23 may have major implications for the pathophysiology of diseases characterized by chronically increased circulating FGF23 concentrations such as chronic kidney disease.
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80
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Puppulin L, Pezzotti G, Sun H, Hosogi S, Nakahari T, Inui T, Kumamoto Y, Tanaka H, Marunaka Y. Raman micro-spectroscopy as a viable tool to monitor and estimate the ionic transport in epithelial cells. Sci Rep 2017; 7:3395. [PMID: 28611439 PMCID: PMC5469862 DOI: 10.1038/s41598-017-03595-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 05/02/2017] [Indexed: 11/18/2022] Open
Abstract
The typical response to the lowering of plasma Na+ concentration and blood pressure in our body involves the release of aldosterone from the adrenal glands, which triggers the reabsorption of sodium in the kidney. Although the effects of aldosterone on this physiological mechanism were extensively studied in the past decades, there are still some aspects to be fully elucidated. In the present study, we propose for the first time a new approach based on Raman spectroscopy to monitor the ionic activity in aldosterone-treated A6 renal epithelial cells. This spectroscopic technique is capable of probing the cells through their thickness in a non-destructive and nimble way. The spectroscopic variations of the Raman bands associated to the O-H stretching of water were correlated to the variations of ionic concentration in the intracellular and extracellular fluids. The increase of Na+ concentration gradients was clearly visualized in the cytosol of aldosterone-treated cells. The enhancement of the Na+ current density induced by aldosterone was estimated from the variation of the ionic chemical potential across the intracellular space. In addition, the variation of the O-H Raman bands of water was used to quantify the cell thickness, which was not affected by aldosterone.
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Affiliation(s)
- Leonardo Puppulin
- Department of Molecular Cell Physiology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto, 602-8566, Japan.
| | - Giuseppe Pezzotti
- Department of Molecular Cell Physiology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto, 602-8566, Japan.,Ceramic Physics Laboratory, Kyoto Institute of Technology, Kyoto, 606-8585, Japan
| | - Hongxin Sun
- Department of Molecular Cell Physiology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto, 602-8566, Japan
| | - Shigekuni Hosogi
- Department of Molecular Cell Physiology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto, 602-8566, Japan
| | - Takashi Nakahari
- Department of Molecular Cell Physiology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto, 602-8566, Japan.,Department of Bio-Ionomics, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto, 602-8566, Japan
| | - Toshio Inui
- Department of Molecular Cell Physiology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto, 602-8566, Japan.,Department of Bio-Ionomics, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto, 602-8566, Japan.,Saisei Mirai Clinics, Moriguchi, 570-0012, Japan
| | - Yasuaki Kumamoto
- Department of Pathology and Cell Regulation, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto, 602-8566, Japan
| | - Hideo Tanaka
- Department of Pathology and Cell Regulation, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto, 602-8566, Japan
| | - Yoshinori Marunaka
- Department of Molecular Cell Physiology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto, 602-8566, Japan. .,Department of Bio-Ionomics, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto, 602-8566, Japan.
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81
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Molina-Jijón E, Rodríguez-Muñoz R, González-Ramírez R, Namorado-Tónix C, Pedraza-Chaverri J, Reyes JL. Aldosterone signaling regulates the over-expression of claudin-4 and -8 at the distal nephron from type 1 diabetic rats. PLoS One 2017; 12:e0177362. [PMID: 28493961 PMCID: PMC5426686 DOI: 10.1371/journal.pone.0177362] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 04/17/2017] [Indexed: 12/19/2022] Open
Abstract
Hyperglycemia in diabetes alters tight junction (TJ) proteins in the kidney. We evaluated the participation of aldosterone (ALD), and the effect of spironolactone (SPL), a mineralocorticoid receptor antagonist, on the expressions of claudin-2, -4, -5 and -8, and occludin in glomeruli, proximal and distal tubules isolated from diabetic rats. Type 1 diabetes was induced in female Wistar rats by a single tail vein injection of streptozotocin (STZ), and SPL was administrated daily by gavage, from days 3–21. Twenty-one days after STZ injection the rats were sacrificed. In diabetic rats, the serum ALD levels were increased, and SPL-treatment did not have effect on these levels or in hyperglycemia, however, proteinuria decreased in SPL-treated diabetic rats. Glomerular damage, evaluated by nephrin and Wilm’s tumor 1 (WT1) protein expressions, and proximal tubular damage, evaluated by kidney injury molecule 1 (Kim-1) and heat shock protein 72 kDa (Hsp72) expressions, were ameliorated by SPL. Also, SPL prevented decrement in claudin-5 in glomeruli, and claudin-2 and occludin in proximal tubules by decreasing oxidative stress, evaluated by superoxide anion (O2●―) production, and oxidative stress markers. In distal tubules, SPL ameliorated increase in mRNA, protein expression, and phosphorylation in threonine residues of claudin-4 and -8, through a serum and glucocorticoid-induced kinase 1 (SGK1), and with-no-lysine kinase 4 (WNK4) signaling pathway. In conclusion, this is the first study that demonstrates that ALD modulates the expression of renal TJ proteins in diabetes, and that the blockade of its actions with SPL, may be a promising therapeutic strategy to prevent alterations of TJ proteins in diabetic nephropathy.
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MESH Headings
- Aldosterone/metabolism
- Animals
- Claudin-4/metabolism
- Claudins/metabolism
- Diabetes Mellitus, Experimental/blood
- Diabetes Mellitus, Experimental/complications
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Experimental/pathology
- Diabetes Mellitus, Type 1/blood
- Diabetes Mellitus, Type 1/complications
- Diabetes Mellitus, Type 1/metabolism
- Diabetes Mellitus, Type 1/pathology
- Female
- Hyperglycemia/blood
- Hyperglycemia/drug therapy
- Hyperglycemia/prevention & control
- Immediate-Early Proteins/metabolism
- Kidney Glomerulus/drug effects
- Kidney Glomerulus/pathology
- Kidney Tubules/drug effects
- Kidney Tubules/pathology
- Models, Biological
- Natriuresis/drug effects
- Nephrons/metabolism
- Oxidative Stress/drug effects
- Phosphorylation/drug effects
- Potassium/blood
- Protein Serine-Threonine Kinases/metabolism
- Proteinuria/blood
- Proteinuria/complications
- Proteinuria/drug therapy
- Proteinuria/prevention & control
- Rats, Wistar
- Signal Transduction/drug effects
- Spironolactone/pharmacology
- Spironolactone/therapeutic use
- Tight Junctions/drug effects
- Tight Junctions/metabolism
- Weight Loss/drug effects
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Affiliation(s)
- Eduardo Molina-Jijón
- Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV-IPN), Mexico City, México
- Departamento de Biociencias e Ingeniería, Centro Interdisciplinario de Investigaciones y Estudios sobre el Medio Ambiente y Desarrollo del Instituto Politécnico Nacional (CIIEMAD-IPN), Mexico City, México
| | - Rafael Rodríguez-Muñoz
- Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV-IPN), Mexico City, México
| | - Ricardo González-Ramírez
- Department of Molecular Biology and Histocompatibility, Dr. Manuel Gea González, General Hospital, Mexico City, México
| | - Carmen Namorado-Tónix
- Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV-IPN), Mexico City, México
| | - José Pedraza-Chaverri
- Department of Biology, Faculty of Chemistry, National Autonomous University of Mexico (UNAM), Mexico City, México
| | - Jose L. Reyes
- Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV-IPN), Mexico City, México
- * E-mail:
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82
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Ong GSY, Young MJ. Mineralocorticoid regulation of cell function: the role of rapid signalling and gene transcription pathways. J Mol Endocrinol 2017; 58:R33-R57. [PMID: 27821439 DOI: 10.1530/jme-15-0318] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 11/06/2016] [Indexed: 12/22/2022]
Abstract
The mineralocorticoid receptor (MR) and mineralocorticoids regulate epithelial handling of electrolytes, and induces diverse effects on other tissues. Traditionally, the effects of MR were ascribed to ligand-receptor binding and activation of gene transcription. However, the MR also utilises a number of intracellular signalling cascades, often by transactivating unrelated receptors, to change cell function more rapidly. Although aldosterone is the physiological mineralocorticoid, it is not the sole ligand for MR. Tissue-selective and mineralocorticoid-specific effects are conferred through the enzyme 11β-hydroxysteroid dehydrogenase 2, cellular redox status and properties of the MR itself. Furthermore, not all aldosterone effects are mediated via MR, with implication of the involvement of other membrane-bound receptors such as GPER. This review will describe the ligands, receptors and intracellular mechanisms available for mineralocorticoid hormone and receptor signalling and illustrate their complex interactions in physiology and disease.
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Affiliation(s)
- Gregory S Y Ong
- Cardiovascular Endocrinology LaboratoryCentre for Endocrinology and Metabolism, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of MedicineSchool of Clinical Sciences, Monash University, Clayton, Victoria, Australia
| | - Morag J Young
- Cardiovascular Endocrinology LaboratoryCentre for Endocrinology and Metabolism, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of PhysiologySchool of Biomedical Sciences, Monash University, Clayton, Victoria, Australia
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83
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Osborne DM, O'Leary KE, Fitzgerald DP, George AJ, Vidal MM, Anderson BM, McNay EC. Context-dependent memory following recurrent hypoglycaemia in non-diabetic rats is mediated via glucocorticoid signalling in the dorsal hippocampus. Diabetologia 2017; 60:182-191. [PMID: 27681242 PMCID: PMC5136318 DOI: 10.1007/s00125-016-4114-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 08/23/2016] [Indexed: 11/24/2022]
Abstract
AIMS/HYPOTHESIS Recurrent hypoglycaemia is primarily caused by repeated over-administration of insulin to patients with diabetes. Although cognition is impaired during hypoglycaemia, restoration of euglycaemia after recurrent hypoglycaemia is associated with improved hippocampally mediated memory. Recurrent hypoglycaemia alters glucocorticoid secretion in response to hypoglycaemia; glucocorticoids are well established to regulate hippocampal processes, suggesting a possible mechanism for recurrent hypoglycaemia modulation of subsequent cognition. We tested the hypothesis that glucocorticoids within the dorsal hippocampus might mediate the impact of recurrent hypoglycaemia on hippocampal cognitive processes. METHODS We characterised changes in the dorsal hippocampus at several time points to identify specific mechanisms affected by recurrent hypoglycaemia, using a well-validated 3 day model of recurrent hypoglycaemia either alone or with intrahippocampal delivery of glucocorticoid (mifepristone) and mineralocorticoid (spironolactone) receptor antagonists prior to each hypoglycaemic episode. RESULTS Recurrent hypoglycaemia enhanced learning and also increased hippocampal expression of glucocorticoid receptors, serum/glucocorticoid-regulated kinase 1, cyclic AMP response element binding (CREB) phosphorylation, and plasma membrane levels of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and N-methyl-D-aspartic acid (NMDA) receptors. Both hippocampus-dependent memory enhancement and the molecular changes were reversed by glucocorticoid receptor antagonist treatment. CONCLUSIONS/INTERPRETATION These results indicate that increased glucocorticoid signalling during recurrent hypoglycaemia produces several changes in the dorsal hippocampus that are conducive to enhanced hippocampus-dependent contextual learning. These changes appear to be adaptive, and in addition to supporting cognition may reduce damage otherwise caused by repeated exposure to severe hypoglycaemia.
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Affiliation(s)
- Danielle M Osborne
- Behavioural Neuroscience, University at Albany, 1400 Washington Avenue, Albany, NY, 12222, USA
| | | | | | - Alvin J George
- Biological Sciences, University at Albany, Albany, NY, USA
| | | | | | - Ewan C McNay
- Behavioural Neuroscience, University at Albany, 1400 Washington Avenue, Albany, NY, 12222, USA.
- Biological Sciences, University at Albany, Albany, NY, USA.
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84
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Murthy M, Kurz T, O'Shaughnessy KM. WNK signalling pathways in blood pressure regulation. Cell Mol Life Sci 2016; 74:1261-1280. [PMID: 27815594 PMCID: PMC5346417 DOI: 10.1007/s00018-016-2402-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 10/17/2016] [Accepted: 10/27/2016] [Indexed: 01/11/2023]
Abstract
Hypertension (high blood pressure) is a major public health problem affecting more than a billion people worldwide with complications, including stroke, heart failure and kidney failure. The regulation of blood pressure is multifactorial reflecting genetic susceptibility, in utero environment and external factors such as obesity and salt intake. In keeping with Arthur Guyton's hypothesis, the kidney plays a key role in blood pressure control and data from clinical studies; physiology and genetics have shown that hypertension is driven a failure of the kidney to excrete excess salt at normal levels of blood pressure. There is a number of rare Mendelian blood pressure syndromes, which have shed light on the molecular mechanisms involved in dysregulated ion transport in the distal kidney. One in particular is Familial hyperkalemic hypertension (FHHt), an autosomal dominant monogenic form of hypertension characterised by high blood pressure, hyperkalemia, hyperchloremic metabolic acidosis, and hypercalciuria. The clinical signs of FHHt are treated by low doses of thiazide diuretic, and it mirrors Gitelman syndrome which features the inverse phenotype of hypotension, hypokalemic metabolic alkalosis, and hypocalciuria. Gitelman syndrome is caused by loss of function mutations in the thiazide-sensitive Na/Cl cotransporter (NCC); however, FHHt patients do not have mutations in the SCL12A3 locus encoding NCC. Instead, mutations have been identified in genes that have revealed a key signalling pathway that regulates NCC and several other key transporters and ion channels in the kidney that are critical for BP regulation. This is the WNK kinase signalling pathway that is the subject of this review.
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Affiliation(s)
- Meena Murthy
- Division of Experimental Medicine and Immunotherapeutics, Department of Medicine, University of Cambridge, Cambridge, CB2 2QQ, UK
| | - Thimo Kurz
- Institute of Molecular Cell and Systems Biology, University of Glasgow, Davidson Building, Glasgow, G12 8QQ, Scotland, UK
| | - Kevin M O'Shaughnessy
- Division of Experimental Medicine and Immunotherapeutics, Department of Medicine, University of Cambridge, Cambridge, CB2 2QQ, UK.
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85
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Pao AC. There and back again: insulin, ENaC, and the cortical collecting duct. Physiol Rep 2016; 4:4/10/e12809. [PMID: 27233302 PMCID: PMC4886174 DOI: 10.14814/phy2.12809] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 05/03/2016] [Indexed: 01/02/2023] Open
Abstract
Cell culture models suggest mechanisms by which insulin stimulates ENaC in the cortical collecting duct. These mechanisms still need to be tested for physiological significance in animal models of insulin resistance.![]()
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Affiliation(s)
- Alan C Pao
- Department of Medicine Stanford University, Stanford, California
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86
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Bouhaddioui W, Provost PR, Tremblay Y. CYP21A2 expression is localized in the developing distal epithelium of the human perinatal lung and is compatible with in situ production and intracrine actions of active glucocorticoids. J Steroid Biochem Mol Biol 2016; 163:12-9. [PMID: 27004467 DOI: 10.1016/j.jsbmb.2016.03.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 03/10/2016] [Accepted: 03/14/2016] [Indexed: 11/29/2022]
Abstract
Glucocorticoids play essential roles in lung development. We investigated for expression of CYP21A2 (21-hydroxylase) as well as for the presence of the corresponding protein and identification of CYP21A2-expressing cells in several human developing lungs. Expression of some related genes was also assessed. CYP21A2 and CYP17A1 (P450c17) mRNAs were found in all the 34 lung samples from 17 to 40 weeks' gestation at variable levels. No correlation was found according to sex but a correlation with age was detected for CYP17A1 only. In contrast, CYP11B1 (11β-hydroxylase)- and CYP11B2 (aldosterone synthase)-mRNAs were not detected. Significant levels of the CYP21A2 protein were detected in all the analyzed samples, while only very low signals were detected for CYP17A1 protein. In situ hybridization revealed that CYP21A2 was almost exclusively expressed in the distal epithelium. It was reported that the lung distal epithelium of human fetuses also express 11β-hydroxysteroid dehydrogenase type 2, which catalyzes cortisol inactivation into cortisone. Based on this information, intracrine glucocorticoid actions should take place from CYP21A2 products through the glucocorticoid receptor in the absence of cortisol. In contrast, mineralocorticoid receptor activation did not seem to depend on deoxycorticosterone produced from local activity of CYP21A2 because of the reported circulating amounts of aldosterone.
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Affiliation(s)
- Wafae Bouhaddioui
- Reproduction, Mother and Youth Health, Centre de recherche CHU de Québec, Québec, QC, Canada; Centre de Recherche en Biologie de la Reproduction (CRBR), Faculté de Médecine, Université Laval, Québec, QC, Canada
| | - Pierre R Provost
- Reproduction, Mother and Youth Health, Centre de recherche CHU de Québec, Québec, QC, Canada; Department of Obstetrics/Gynecology & Reproduction, Faculty of Medicine, Université Laval, Québec, QC, Canada; Centre de Recherche en Biologie de la Reproduction (CRBR), Faculté de Médecine, Université Laval, Québec, QC, Canada
| | - Yves Tremblay
- Reproduction, Mother and Youth Health, Centre de recherche CHU de Québec, Québec, QC, Canada; Department of Obstetrics/Gynecology & Reproduction, Faculty of Medicine, Université Laval, Québec, QC, Canada; Centre de Recherche en Biologie de la Reproduction (CRBR), Faculté de Médecine, Université Laval, Québec, QC, Canada.
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87
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(Pro)renin receptor contributes to regulation of renal epithelial sodium channel. J Hypertens 2016; 34:486-94; discussion 494. [PMID: 26771338 DOI: 10.1097/hjh.0000000000000825] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Recent studies reported increased (Pro)renin receptor (PRR) expression during low-salt intake. We hypothesized that PRR plays a role in regulation of renal epithelial sodium channel (ENaC) through serum and glucocorticoid-inducible kinase isoform 1 (SGK-1)-neural precursor cell expressed, developmentally downregulated 4-2 (Nedd4-2) signaling pathway. METHOD Male Sprague-Dawley rats on normal-sodium diet and mouse renal inner medullary collecting duct cells treated with NaCl at 130 mmol/l (normal salt), or 63 mmol/l (low salt) were studied. PRR and α-ENaC expressions were evaluated 1 week after right uninephrectomy and left renal interstitial administration of 5% dextrose, scramble shRNA, or PRR shRNA (n = 6 each treatment). RESULTS In-vivo PRR shRNA significantly reduced expressions of PRR throughout the kidney and α-ENaC subunits in the renal medulla. In inner medullary collecting duct cells, low salt or angiotensin II (Ang II) augmented the mRNA and protein expressions of PRR (P < 0.05), SGK-1 (P < 0.05), and α-ENaC (P < 0.05). Low salt or Ang II increased the phosphorylation of Nedd4-2. In cells treated with low salt or Ang II, PRR siRNA significantly downregulated the mRNA and protein expressions of PRR (P < 0.05), SGK-1 (P < 0.05), and α-ENaC expression (P < 0.05). CONCLUSION We conclude that PRR contributes to the regulation of α-ENaC via SGK-1-Nedd4-2 signaling pathway.
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88
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Valinsky WC, Jolly A, Miquel P, Touyz RM, Shrier A. Aldosterone Upregulates Transient Receptor Potential Melastatin 7 (TRPM7). J Biol Chem 2016; 291:20163-72. [PMID: 27466368 PMCID: PMC5025699 DOI: 10.1074/jbc.m116.735175] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 07/26/2016] [Indexed: 12/18/2022] Open
Abstract
Transient receptor potential melastatin 7 (TRPM7) is a ubiquitously expressed Mg(2+)-permeable ion channel fused to a C-terminal α-kinase domain. Recently, aldosterone was shown to increase intracellular Mg(2+) levels and alter inflammatory signaling in TRPM7-expressing HEK293 cells. This study was undertaken to assess whether these effects were related to an aldosterone-mediated increase of TRPM7 current and/or plasma membrane localization. Using HEK293 cells stably expressing WT-TRPM7, we found that 18-h application of aldosterone significantly increased TRPM7 current and TRPM7 plasma membrane protein expression by 48% and 34%, respectively. The aldosterone-mediated increase of TRPM7 current was inhibited by eplerenone, a mineralocorticoid receptor (MR) blocker, and GSK-650394, an inhibitor of the serum- and glucocorticoid-regulated kinase 1 (SGK1). SGK1 blockade also prevented the aldosterone-induced increase of TRPM7 plasma membrane protein. It was further determined that K1648R-TRPM7, the phosphotransferase-inactive TRPM7 mutant, was unresponsive to aldosterone. Therefore, chronic aldosterone treatment increases the plasma membrane expression of TRPM7, which is associated with an increase of TRPM7 current. This process occurs via an MR-dependent, genomic signaling cascade involving SGK1 and a functioning TRPM7 α-kinase domain. We suggest that this mechanism may be of general relevance when interpreting the effects of aldosterone because the MR receptor is found in multiple tissues, and TRPM7 and SGK1 are ubiquitously expressed.
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Affiliation(s)
- William C Valinsky
- From the Department of Physiology, McGill University, Montreal, Quebec H3G 0B1, Canada and
| | - Anna Jolly
- From the Department of Physiology, McGill University, Montreal, Quebec H3G 0B1, Canada and
| | - Perrine Miquel
- From the Department of Physiology, McGill University, Montreal, Quebec H3G 0B1, Canada and
| | - Rhian M Touyz
- the Institute of Cardiovascular and Medical Sciences, University of Glasgow, BHF GCRC, 126 University Place, Glasgow G12 8TA, United Kingdom
| | - Alvin Shrier
- From the Department of Physiology, McGill University, Montreal, Quebec H3G 0B1, Canada and
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89
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Iatrino R, Manunta P, Zagato L. Salt Sensitivity: Challenging and Controversial Phenotype of Primary Hypertension. Curr Hypertens Rep 2016; 18:70. [DOI: 10.1007/s11906-016-0677-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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90
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Abstract
Fibroblast growth factor-23 (FGF23) is a bone-derived hormone known to suppress phosphate reabsorption and vitamin D hormone production in the kidney. Klotho was originally discovered as an anti-aging factor, but the functional role of Klotho is still a controversial issue. Three major functions have been proposed, a hormonal function of soluble Klotho, an enzymatic function as glycosidase, and the function as an obligatory co-receptor for FGF23 signaling. The purpose of this review is to highlight the recent advances in the area of FGF23 and Klotho signaling in the kidney, in the parathyroid gland, in the cardiovascular system, in bone, and in the central nervous system. During recent years, major new functions of FGF23 and Klotho have been discovered in these organ systems. Based on these novel findings, FGF23 has emerged as a pleiotropic endocrine and auto-/paracrine factor influencing not only mineral metabolism but also cardiovascular function.
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91
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Proanthocyanidins block aldosterone-dependent up-regulation of cardiac gamma ENaC and Nedd4-2 inactivation via SGK1. J Nutr Biochem 2016; 37:13-19. [PMID: 27592201 DOI: 10.1016/j.jnutbio.2016.07.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 06/10/2016] [Accepted: 07/15/2016] [Indexed: 11/21/2022]
Abstract
Aldosterone plays a central role in the development of cardiac pathological states involving ion transport imbalances, especially sodium transport. We have previously demonstrated a cardioprotective effect of proanthocyanidins in aldosterone-treated rats. Our objective was to investigate for the first time the effect of proanthocyanidins on serum and glucocorticoid-regulated kinase 1 (SGK1), epithelial Na+ channel (γ-ENaC), neuronal precursor cells expressed developmentally down-regulated 4-2 (Nedd4-2) and phosphoNedd4-2 protein expression in the hearts of aldosterone-treated rats. Male Wistar rats received aldosterone (1mg kg-1day-1)+1% NaCl for 3weeks. Half of the animals in each group were simultaneously treated with the proanthocyanidins-rich extract (80% w/w) (PRO80, 5mg kg-1day-1). Hypertension and diastolic dysfunction induced by aldosterone were abolished by treatment with PRO80. Expression of fibrotic, inflammatory and oxidative mediators were increased by aldosterone-salt administration and blunted by PRO80. Antioxidant capacity was improved by PRO80. The up-regulated aldosterone mediator SGK1, ENaC and p-Nedd4-2/total Nedd4-2 ratio were blocked by PRO80. PRO80 blunted aldosterone-mineralocorticoid-mediated up-regulation of ENaC provides new mechanistic insight of the beneficial effect of proanthocyanidins preventing the cardiac alterations induced by aldosterone excess.
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92
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Lou Y, Zhang F, Luo Y, Wang L, Huang S, Jin F. Serum and Glucocorticoid Regulated Kinase 1 in Sodium Homeostasis. Int J Mol Sci 2016; 17:ijms17081307. [PMID: 27517916 PMCID: PMC5000704 DOI: 10.3390/ijms17081307] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 08/02/2016] [Accepted: 08/03/2016] [Indexed: 12/13/2022] Open
Abstract
The ubiquitously expressed serum and glucocorticoid regulated kinase 1 (SGK1) is tightly regulated by osmotic and hormonal signals, including glucocorticoids and mineralocorticoids. Recently, SGK1 has been implicated as a signal hub for the regulation of sodium transport. SGK1 modulates the activities of multiple ion channels and carriers, such as epithelial sodium channel (ENaC), voltage-gated sodium channel (Nav1.5), sodium hydrogen exchangers 1 and 3 (NHE1 and NHE3), sodium-chloride symporter (NCC), and sodium-potassium-chloride cotransporter 2 (NKCC2); as well as the sodium-potassium adenosine triphosphatase (Na+/K+-ATPase) and type A natriuretic peptide receptor (NPR-A). Accordingly, SGK1 is implicated in the physiology and pathophysiology of Na+ homeostasis. Here, we focus particularly on recent findings of SGK1’s involvement in Na+ transport in renal sodium reabsorption, hormone-stimulated salt appetite and fluid balance and discuss the abnormal SGK1-mediated Na+ reabsorption in hypertension, heart disease, edema with diabetes, and embryo implantation failure.
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Affiliation(s)
- Yiyun Lou
- Department of Reproductive Endocrinology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, Zhejiang, China.
- Department of Gynaecology, Hangzhou Hospital of Traditional Chinese Medicine, Hangzhou 310007, Zhejiang, China.
| | - Fan Zhang
- Department of Reproductive Endocrinology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, Zhejiang, China.
| | - Yuqin Luo
- Department of Reproductive Endocrinology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, Zhejiang, China.
| | - Liya Wang
- Department of Reproductive Endocrinology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, Zhejiang, China.
| | - Shisi Huang
- Department of Reproductive Endocrinology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, Zhejiang, China.
| | - Fan Jin
- Department of Reproductive Endocrinology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, Zhejiang, China.
- Key Laboratory of Reproductive Genetics, National Ministry of Education (Zhejiang University), Women's Reproductive Healthy Laboratory of Zhejiang Province, Hangzhou 310058, Zhejiang, China.
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93
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Yang L, Frindt G, Lang F, Kuhl D, Vallon V, Palmer LG. SGK1-dependent ENaC processing and trafficking in mice with high dietary K intake and elevated aldosterone. Am J Physiol Renal Physiol 2016; 312:F65-F76. [PMID: 27413200 DOI: 10.1152/ajprenal.00257.2016] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 07/06/2016] [Indexed: 02/04/2023] Open
Abstract
We examined renal Na and K transporters in mice with deletions in the gene encoding the aldosterone-induced protein SGK1. The knockout mice were hyperkalemic, and had altered expression of the subunits of the epithelial Na channel (ENaC). The kidneys showed decreased expression of the cleaved forms of the γENaC subunit, and the fully glycosylated form of the βENaC subunits when animals were fed a high-K diet. Knockout animals treated with exogenous aldosterone also had reduced subunit processing and diminished surface expression of βENaC and γENaC. Expression of the three upstream Na transporters NHE3, NKCC2, and NCC was reduced in both wild-type and knockout mice in response to K loading. The activity of ENaC measured as whole cell amiloride-sensitive current (INa) in principal cells of the cortical collecting duct (CCD) was minimal under control conditions but was increased by a high-K diet to a similar extent in knockout and wild-type animals. INa in the connecting tubule also increased similarly in the two genotypes in response to exogenous aldosterone administration. The activities of both ROMK channels in principal cells and BK channels in intercalated cells of the CCD were unaffected by the deletion of SGK1. Acute treatment of animals with amiloride produced similar increases in Na excretion and decreases in K excretion in the two genotypes. The absence of changes in ENaC activity suggests compensation for decreased surface expression. Altered K balance in animals lacking SGK1 may reflect defects in ENaC-independent K excretion.
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Affiliation(s)
- Lei Yang
- Department of Physiology and Biophysics, Weill-Cornell Medical College, New York, New York.,Department of Physiology, Harbin Medical University, Harbin, China
| | - Gustavo Frindt
- Department of Physiology and Biophysics, Weill-Cornell Medical College, New York, New York
| | - Florian Lang
- Department of Cardiology, Vascular Medicine and Physiology, University of Tübingen, Tübingen, Germany
| | - Dietmar Kuhl
- Institute for Molecular and Cellular Cognition, Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and
| | - Volker Vallon
- Departments of Medicine and Pharmacology, University of California San Diego and Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Lawrence G Palmer
- Department of Physiology and Biophysics, Weill-Cornell Medical College, New York, New York;
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94
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Xu D, Wang H, You G. Posttranslational Regulation of Organic Anion Transporters by Ubiquitination: Known and Novel. Med Res Rev 2016; 36:964-79. [PMID: 27291023 DOI: 10.1002/med.21397] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 04/27/2016] [Accepted: 04/27/2016] [Indexed: 12/25/2022]
Abstract
Organic anion transporters (OATs) encoded by solute carrier 22 family are localized in the epithelia of multiple organs, where they mediate the absorption, distribution, and excretion of a diverse array of negatively charged environmental toxins and clinically important drugs. Alterations in the expression and function of OATs play important roles in intra- and interindividual variability of the therapeutic efficacy and the toxicity of many drugs. As a result, the activity of OATs must be under tight regulation so as to carry out their normal functions. The regulation of OAT transport activity in response to various stimuli can occur at several levels such as transcription, translation, and posttranslational modification. Posttranslational regulation is of particular interest, because it usually happens within a very short period of time (minutes to hours) when the body has to deal with rapidly changing amounts of substances as a consequence of variable intake of drugs, fluids, or meals as well as metabolic activity. This review article highlights the recent advances from our laboratory in uncovering several posttranslational mechanisms underlying OAT regulation. These advances offer the promise of identifying targets for novel strategies that will maximize therapeutic efficacy in drug development.
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Affiliation(s)
- Da Xu
- Department of Pharmaceutics, Rutgers University, Piscataway, New Jersey, 08854
| | - Haoxun Wang
- Department of Pharmaceutics, Rutgers University, Piscataway, New Jersey, 08854
| | - Guofeng You
- Department of Pharmaceutics, Rutgers University, Piscataway, New Jersey, 08854
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95
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Minegishi S, Ishigami T, Kino T, Chen L, Nakashima-Sasaki R, Araki N, Yatsu K, Fujita M, Umemura S. An isoform of Nedd4-2 is critically involved in the renal adaptation to high salt intake in mice. Sci Rep 2016; 6:27137. [PMID: 27256588 PMCID: PMC4891730 DOI: 10.1038/srep27137] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 05/13/2016] [Indexed: 11/14/2022] Open
Abstract
Epithelial sodium channels (ENaCs) play critical roles in the maintenance of fluid and electrolyte homeostasis, and their genetic abnormalities cause one type of hereditary salt-sensitive hypertension, Liddle syndrome. As we reported previously, both human and rodent Nedd4L/Nedd4-2 showed molecular diversity, with and without a C2 domain in their N-terminal. Nedd4L/Nedd4-2 isoforms with a C2 domain are hypothesized to be related closely to ubiquitination of ENaCs. We generated Nedd4-2 C2 domain knockout mice. We demonstrate here that loss of Nedd4-2 C2 isoform causes salt-sensitive hypertension under conditions of a high dietary salt intake in vivo. The knockout mice had reduced urinary sodium excretion, osmotic pressure and increased water intake and urine volume with marked dilatation of cortical tubules while receiving a high salt diet. To the contrary, there was no difference in metabolic data between wild-type and knockout mice receiving a normal control diet. In the absence of Nedd4-2 C2 domain, a high salt intake accelerated ENaC expression. Coimmunoprecipitation studies revealed suppressed ubiquitination for ENaC with a high salt intake. Taken together, our findings demonstrate that during a high oral salt intake the Nedd4-2 C2 protein plays a pivotal role in maintaining adaptive salt handling in the kidney.
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Affiliation(s)
- Shintaro Minegishi
- Yokohama City University Graduate School of Medicine, Department of Medical Science and Cardio-Renal Medicine
| | - Tomoaki Ishigami
- Yokohama City University Graduate School of Medicine, Department of Medical Science and Cardio-Renal Medicine
| | - Tabito Kino
- Yokohama City University Graduate School of Medicine, Department of Medical Science and Cardio-Renal Medicine
| | - Lin Chen
- Yokohama City University Graduate School of Medicine, Department of Medical Science and Cardio-Renal Medicine
| | - Rie Nakashima-Sasaki
- Yokohama City University Graduate School of Medicine, Department of Medical Science and Cardio-Renal Medicine
| | - Naomi Araki
- Yokohama City University Graduate School of Medicine, Department of Medical Science and Cardio-Renal Medicine
| | - Keisuke Yatsu
- Yokohama City University Graduate School of Medicine, Department of Medical Science and Cardio-Renal Medicine
| | - Megumi Fujita
- Yokohama City University Graduate School of Medicine, Department of Medical Science and Cardio-Renal Medicine
| | - Satoshi Umemura
- Yokohama City University Graduate School of Medicine, Department of Medical Science and Cardio-Renal Medicine
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96
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Xu D, Huang H, Toh MF, You G. Serum- and glucocorticoid-inducible kinase sgk2 stimulates the transport activity of human organic anion transporters 1 by enhancing the stability of the transporter. INTERNATIONAL JOURNAL OF BIOCHEMISTRY AND MOLECULAR BIOLOGY 2016; 7:19-26. [PMID: 27335683 PMCID: PMC4913228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 12/14/2015] [Indexed: 06/06/2023]
Abstract
Human organic anion transporter 1 (hOAT1) belongs to a family of organic anion transporters that play critical roles in the body disposition of clinically important drugs, including anti-viral therapeutics, anti-cancer drugs, antibiotics, antihypertensives, and anti-inflammatories. hOAT1 is abundantly expressed in the kidney and brain. In the current study, we examined the regulation of hOAT1 by serum- and glucocorticoid-inducible kinase 2 (sgk2) in the kidney COS-7 cells. We showed that sgk2 stimulated hOAT1 transport activity. Such stimulation mainly resulted from an increased cell surface expression of the transporter, kinetically revealed as an increased maximal transport velocity V max without significant change in substrate-binding affinity K m. We further showed that stimulation of hOAT1 activity by sgk2 was achieved by preventing hOAT1 degradation. Our co-immunoprecipitation experiment revealed that the effect of sgk2 on hOAT1 was through a direct interaction between these two proteins. In conclusion, our study demonstrated that sgk2 stimulates hOAT1 transport activity by enhancing the stability of the transporter. This study provides the insights into sgk2 regulation of hOAT1-mediated transport in normal physiology and disease.
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Affiliation(s)
- Da Xu
- Department of Pharmaceutics, Rutgers, The State University of New Jersey Piscataway, NJ 08854, USA
| | - Haozhe Huang
- Department of Pharmaceutics, Rutgers, The State University of New Jersey Piscataway, NJ 08854, USA
| | - May Fern Toh
- Department of Pharmaceutics, Rutgers, The State University of New Jersey Piscataway, NJ 08854, USA
| | - Guofeng You
- Department of Pharmaceutics, Rutgers, The State University of New Jersey Piscataway, NJ 08854, USA
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97
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Jacobs ME, Kathpalia PP, Chen Y, Thomas SV, Noonan EJ, Pao AC. SGK1 regulation by miR-466g in cortical collecting duct cells. Am J Physiol Renal Physiol 2016; 310:F1251-7. [PMID: 26911843 PMCID: PMC4935769 DOI: 10.1152/ajprenal.00024.2016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 02/22/2016] [Indexed: 11/22/2022] Open
Abstract
Micro-RNAs (miRNAs) are noncoding RNAs that bind target mRNA transcripts and modulate gene expression. In the cortical collecting duct (CCD), aldosterone stimulates the expression of genes that increase activity of the epithelial sodium channel (ENaC); in the early phase of aldosterone induction, one such gene is serum and glucocorticoid regulated kinase 1 (SGK1). We hypothesized that aldosterone regulates the expression of miRNAs in the early phase of induction to control the expression of target genes that stimulate ENaC activity. We treated mpkCCDc14 cells with aldosterone or vehicle for 1 h and used a miRNA microarray to analyze differential miRNA expression. We identified miR-466g as a miRNA that decreased by 57% after 1 h of aldosterone treatment. Moreover, we identified a putative miR-466g binding site in the 3'-untranslated region of SGK1. We constructed an SGK1 3'-untranslated region luciferase reporter and found that cotransfection of miR-466g suppressed luciferase activity in human embryonic kidney-293 cells in a dose-dependent manner. Deletion or introduction of point mutations that disrupt the miR-466g target site attenuated miR-466g-directed suppression of luciferase activity. Finally, we generated stably transduced mpkCCDc14 cell lines overexpressing miR-466g. Cells overexpressing miR-466g demonstrated 12.9-fold lower level of SGK1 mRNA compared with control cells after 6 h of aldosterone induction; moreover, cells overexpressing miR-466g exhibited 25% decrease in amiloride-sensitive current after 6 h of aldosterone induction and complete loss of amiloride-sensitive current after 24 h of aldosterone induction. Our findings implicate miR-466g as a novel early-phase aldosterone responsive miRNA that regulates SGK1 and ENaC in CCD cells.
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Affiliation(s)
- Mollie E Jacobs
- Department of Medicine, Stanford University School of Medicine, Stanford, California; and
| | - Paru P Kathpalia
- Department of Medicine, Stanford University School of Medicine, Stanford, California; and
| | - Yu Chen
- Veterans Affairs Palo Alto Health Care System, Palo Alto, California
| | - Sheela V Thomas
- Department of Medicine, Stanford University School of Medicine, Stanford, California; and
| | - Emily J Noonan
- Department of Medicine, Stanford University School of Medicine, Stanford, California; and Veterans Affairs Palo Alto Health Care System, Palo Alto, California
| | - Alan C Pao
- Department of Medicine, Stanford University School of Medicine, Stanford, California; and Veterans Affairs Palo Alto Health Care System, Palo Alto, California
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98
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Abstract
PURPOSE OF REVIEW Fibroblast growth factor-23 (FGF23) is a bone-derived hormone known to suppress phosphate reabsorption in the kidney. The purpose of this review was to highlight the recent advances in the area of FGF23-regulated solute transport in the kidney. RECENT FINDINGS Recent evidence suggests that FGF23 suppresses phosphate reabsorption in renal proximal tubular epithelium by a Klotho-dependent, FGF receptor (FGFR)-1 and FGFR4-mediated signaling mechanism that may also involve Janus kinase 3. Moreover, it was recently established that FGF23 signaling in the distal renal tubule targets with-no-lysine kinase-4 (WNK4), a key molecule in the regulation of solute transport in the distal nephron. By targeting WNK4, FGF23 has been shown to increase the membrane abundance of the epithelial calcium channel TRPV5 and of the sodium-chloride cotransporter NCC, resulting in augmented renal calcium and sodium reabsorption. SUMMARY Significant progress has been made in the further characterization of the signaling pathways involved in the FGF23-induced inhibition of phosphate transport in proximal tubular epithelium, and major new functions of FGF23 in solute transport have been discovered in distal renal tubules. The calcium- and sodium-conserving functions of FGF23 may have major implications for the pathophysiology of cardiovascular diseases. VIDEO ABSTRACT.
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99
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Cerecedo D, Martínez-Vieyra I, Sosa-Peinado A, Cornejo-Garrido J, Ordaz-Pichardo C, Benítez-Cardoza C. Alterations in plasma membrane promote overexpression and increase of sodium influx through epithelial sodium channel in hypertensive platelets. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:1891-903. [PMID: 27137675 DOI: 10.1016/j.bbamem.2016.04.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 03/31/2016] [Accepted: 04/27/2016] [Indexed: 12/30/2022]
Abstract
Platelets are small, anucleated cell fragments that activate in response to a wide variety of stimuli, triggering a complex series of intracellular pathways leading to a hemostatic thrombus formation at vascular injury sites. However, in essential hypertension, platelet activation contributes to causing myocardial infarction and ischemic stroke. Reported abnormalities in platelet functions, such as platelet hyperactivity and hyperaggregability to several agonists, contribute to the pathogenesis and complications of thrombotic events associated with hypertension. Platelet membrane lipid composition and fluidity are determining for protein site accessibility, structural arrangement of platelet surface, and response to appropriate stimuli. The present study aimed to demonstrate whether structural and biochemical abnormalities in lipid membrane composition and fluidity characteristic of platelets from hypertensive patients influence the expression of the Epithelial Sodium Channel (ENaC), fundamental for sodium influx during collagen activation. Wb, cytometry and quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) assays demonstrated ENaC overexpression in platelets from hypertensive subjects and in relation to control subjects. Additionally, our results strongly suggest a key role of β-dystroglycan as a scaffold for the organization of ENaC and associated proteins. Understanding of the mechanisms of platelet alterations in hypertension should provide valuable information for the pathophysiology of hypertension.
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Affiliation(s)
- D Cerecedo
- Laboratorio de Hematobiología, Escuela Nacional de Medicina y Homeopatía (ENMH), Instituto Politécnico Nacional (IPN), México City, México.
| | - Ivette Martínez-Vieyra
- Laboratorio de Hematobiología, Escuela Nacional de Medicina y Homeopatía (ENMH), Instituto Politécnico Nacional (IPN), México City, México
| | - Alejandro Sosa-Peinado
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), P.O. Box 70-159, 04510, D.F., México City, México
| | - Jorge Cornejo-Garrido
- Laboratorio de Biología Celular y Productos Naturales, ENMH, IPN, México City, México
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Al-Qusairi L, Basquin D, Roy A, Stifanelli M, Rajaram RD, Debonneville A, Nita I, Maillard M, Loffing J, Subramanya AR, Staub O. Renal tubular SGK1 deficiency causes impaired K+ excretion via loss of regulation of NEDD4-2/WNK1 and ENaC. Am J Physiol Renal Physiol 2016; 311:F330-42. [PMID: 27009335 DOI: 10.1152/ajprenal.00002.2016] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2016] [Accepted: 03/21/2016] [Indexed: 11/22/2022] Open
Abstract
The stimulation of postprandial K(+) clearance involves aldosterone-independent and -dependent mechanisms. In this context, serum- and glucocorticoid-induced kinase (SGK)1, a ubiquitously expressed kinase, is one of the primary aldosterone-induced proteins in the aldosterone-sensitive distal nephron. Germline inactivation of SGK1 suggests that this kinase is fundamental for K(+) excretion under conditions of K(+) load, but the specific role of renal SGK1 remains elusive. To avoid compensatory mechanisms that may occur during nephrogenesis, we used inducible, nephron-specific Sgk1(Pax8/LC1) mice to assess the role of renal tubular SGK1 in K(+) regulation. Under a standard diet, these animals exhibited normal K(+) handling. When challenged by a high-K(+) diet, they developed severe hyperkalemia accompanied by a defect in K(+) excretion. Molecular analysis revealed reduced neural precursor cell expressed developmentally downregulated protein (NEDD)4-2 phosphorylation and total expression. γ-Epithelial Na(+) channel (ENaC) expression and α/γENaC proteolytic processing were also decreased in mutant mice. Moreover, with no lysine kinase (WNK)1, which displayed in control mice punctuate staining in the distal convoluted tubule and diffuse distribution in the connecting tubule/cortical colleting duct, was diffused in the distal convoluted tubule and less expressed in the connecting tubule/collecting duct of Sgk(Pax8/LC1) mice. Moreover, Ste20-related proline/alanine-rich kinase phosphorylation, and Na(+)-Cl(-) cotransporter phosphorylation/apical localization were reduced in mutant mice. Consistent with the altered WNK1 expression, increased renal outer medullary K(+) channel apical localization was observed. In conclusion, our data suggest that renal tubular SGK1 is important in the regulation of K(+) excretion via the control of NEDD4-2, WNK1, and ENaC.
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Affiliation(s)
- Lama Al-Qusairi
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland; National Centre of Competence in Research "Kidney.ch," Lausanne, Switzerland
| | - Denis Basquin
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland; National Centre of Competence in Research "Kidney.ch," Lausanne, Switzerland
| | - Ankita Roy
- Department of Medicine, University of Pittsburgh School of Medicine and Veterans Affairs Pittsburgh Healthcare System, Pittsburgh, Pennsylvania
| | - Matteo Stifanelli
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
| | - Renuga Devi Rajaram
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
| | - Anne Debonneville
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
| | - Izabela Nita
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
| | - Marc Maillard
- Service of Nephrology, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Johannes Loffing
- Institute of Anatomy, University of Zurich, Zurich, Switzerland; and National Centre of Competence in Research "Kidney.ch," Lausanne, Switzerland
| | - Arohan R Subramanya
- Department of Medicine, University of Pittsburgh School of Medicine and Veterans Affairs Pittsburgh Healthcare System, Pittsburgh, Pennsylvania
| | - Olivier Staub
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland; National Centre of Competence in Research "Kidney.ch," Lausanne, Switzerland
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