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Abstract
Salt (sodium chloride) is an essential nutrient required to maintain physiological functions. However, for most people, daily salt intake far exceeds their physiological need and is habitually greater than recommended upper thresholds. Excess salt intake leads to elevation in blood pressure which drives cardiovascular morbidity and mortality. Indeed, excessive salt intake is estimated to be responsible for ≈5 million deaths per year globally. For approximately one-third of otherwise healthy individuals (and >50% of those with hypertension), the effect of salt intake on blood pressure elevation is exaggerated; such people are categorized as salt sensitive and salt sensitivity of blood pressure is considered an independent risk factor for cardiovascular disease and death. The prevalence of salt sensitivity is higher in women than in men and, in both, increases with age. This narrative review considers the foundational concepts of salt sensitivity and the underlying effector systems that cause salt sensitivity. We also consider recent updates in preclinical and clinical research that are revealing new modifying factors that determine the blood pressure response to high salt intake.
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Affiliation(s)
- Matthew A Bailey
- Edinburgh Kidney, University/BHF Centre for Cardiovascular Science, The Queen's Medical Research Institute, University of Edinburgh, United Kingdom (M.A.B., N.D.)
| | - Neeraj Dhaun
- Edinburgh Kidney, University/BHF Centre for Cardiovascular Science, The Queen's Medical Research Institute, University of Edinburgh, United Kingdom (M.A.B., N.D.)
- Department of Renal Medicine, Royal Infirmary of Edinburgh, United Kingdom (N.D.)
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Uneda K, Kawai Y, Kaneko A, Kayo T, Akiba S, Ishigami T, Yoshida-Komiya H, Suzuki M, Mitsuma T. Analysis of clinical factors associated with Kampo formula-induced pseudoaldosteronism based on self-reported information from the Japanese Adverse Drug Event Report database. PLoS One 2024; 19:e0296450. [PMID: 38165850 PMCID: PMC10760746 DOI: 10.1371/journal.pone.0296450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 12/10/2023] [Indexed: 01/04/2024] Open
Abstract
Drug-induced pseudoaldosteronism is a typical adverse effect of Kampo formulas. Previous research described the potential risks of Kampo formula-linked pseudoaldosteronism. However, few studies assessed the risk factors using a real-world database and a data-mining approach. Using the Japanese Adverse Drug Event Report database, we extracted pseudoaldosteronism reports for 148 Kampo formulas covered by Japanese national health insurance. Adverse events were decided according to the preferred terminology of the Medical Dictionary for Regulatory Activities/Japanese version 25.1. We calculated reporting odds ratio (RORs) and identified Kampo formulas as suspected causes of pseudoaldosteronism. Moreover, we evaluated clinical factors associated with Kampo formula-induced pseudoaldosteronism via logistic regression. From April 2004 to November 2022, 6334 adverse events related to the Kampo formulas were reported. We selected 2471 reports containing complete clinical data, including 210 reports on pseudoaldosteronism. In the pseudoaldosteronism group, 69.0% of patients were female, and 85.2% were ≥70 years old. The formulas most commonly associated with pseudoaldosteronism were Shakuyakukanzoto, Yokukansan, and Ryokeijutsukanto (ROR [95% confidence interval {CI}] = 18.3 [13.0-25.9], 8.1 [5.4-12.0], and 5.5 [1.4-21.9], respectively). Logistic analysis identified female sex (odds ratio [OR] [95% CI] = 1.7 [1.2-2.6]; P = 0.006), older age (≥70, 5.0 [3.2-7.8]; P < 0.001), low body weight (<50 kg, 2.2 [1.5-3.2]; P < 0.001), diuretics usage (2.1 [1.3-4.8]; P = 0.004), hypertension (1.6 [1.1-2.4]; P = 0.014), and dementia (7.0 [4.2-11.6]; P < 0.001) as pseudoaldosteronism-related factors. Additionally, the daily Glycyrrhiza dose (OR = 2.1 [1.9-2.3]; P < 0.001) and duration of administration (>14 days, OR = 2.8 [1.7-4.5]; P < 0.001) were associated with adverse events. We did not observe an interaction between aging and hypertension. Careful follow-up is warranted during long-term Glycyrrhiza-containing Kampo formula use in patients with multiple clinical factors for pseudoaldosteronism.
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Affiliation(s)
- Kazushi Uneda
- Department of Kampo Medicine, Aizu Medical Center, Fukushima Medical University, Fukushima, Aizuwakamatsu, Japan
- Department of Medical Science and Cardiorenal Medicine, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Yuki Kawai
- Department of Medical Science and Cardiorenal Medicine, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Akira Kaneko
- Department of Kampo Medicine, Aizu Medical Center, Fukushima Medical University, Fukushima, Aizuwakamatsu, Japan
| | - Takumi Kayo
- Department of Kampo Medicine, Aizu Medical Center, Fukushima Medical University, Fukushima, Aizuwakamatsu, Japan
| | - Shuichiro Akiba
- Department of Kampo Medicine, Aizu Medical Center, Fukushima Medical University, Fukushima, Aizuwakamatsu, Japan
| | - Tomoaki Ishigami
- Department of Medical Science and Cardiorenal Medicine, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | | | - Masao Suzuki
- Department of Kampo Medicine, Aizu Medical Center, Fukushima Medical University, Fukushima, Aizuwakamatsu, Japan
| | - Tadamichi Mitsuma
- Department of Kampo Medicine, Aizu Medical Center, Fukushima Medical University, Fukushima, Aizuwakamatsu, Japan
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Johnston JG, Welch AK, Cain BD, Sayeski PP, Gumz ML, Wingo CS. Aldosterone: Renal Action and Physiological Effects. Compr Physiol 2023; 13:4409-4491. [PMID: 36994769 DOI: 10.1002/cphy.c190043] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Aldosterone exerts profound effects on renal and cardiovascular physiology. In the kidney, aldosterone acts to preserve electrolyte and acid-base balance in response to changes in dietary sodium (Na+ ) or potassium (K+ ) intake. These physiological actions, principally through activation of mineralocorticoid receptors (MRs), have important effects particularly in patients with renal and cardiovascular disease as demonstrated by multiple clinical trials. Multiple factors, be they genetic, humoral, dietary, or otherwise, can play a role in influencing the rate of aldosterone synthesis and secretion from the adrenal cortex. Normally, aldosterone secretion and action respond to dietary Na+ intake. In the kidney, the distal nephron and collecting duct are the main targets of aldosterone and MR action, which stimulates Na+ absorption in part via the epithelial Na+ channel (ENaC), the principal channel responsible for the fine-tuning of Na+ balance. Our understanding of the regulatory factors that allow aldosterone, via multiple signaling pathways, to function properly clearly implicates this hormone as central to many pathophysiological effects that become dysfunctional in disease states. Numerous pathologies that affect blood pressure (BP), electrolyte balance, and overall cardiovascular health are due to abnormal secretion of aldosterone, mutations in MR, ENaC, or effectors and modulators of their action. Study of the mechanisms of these pathologies has allowed researchers and clinicians to create novel dietary and pharmacological targets to improve human health. This article covers the regulation of aldosterone synthesis and secretion, receptors, effector molecules, and signaling pathways that modulate its action in the kidney. We also consider the role of aldosterone in disease and the benefit of mineralocorticoid antagonists. © 2023 American Physiological Society. Compr Physiol 13:4409-4491, 2023.
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Affiliation(s)
- Jermaine G Johnston
- Division of Nephrology, Hypertension and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida, USA
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida, USA
- Nephrology Section, Veteran Administration Medical Center, North Florida/South Georgia Malcom Randall Department of Veterans Affairs Medical Center, Gainesville, Florida, USA
| | - Amanda K Welch
- Division of Nephrology, Hypertension and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida, USA
- Nephrology Section, Veteran Administration Medical Center, North Florida/South Georgia Malcom Randall Department of Veterans Affairs Medical Center, Gainesville, Florida, USA
| | - Brian D Cain
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida, USA
| | - Peter P Sayeski
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida, USA
| | - Michelle L Gumz
- Division of Nephrology, Hypertension and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida, USA
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida, USA
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida, USA
- Nephrology Section, Veteran Administration Medical Center, North Florida/South Georgia Malcom Randall Department of Veterans Affairs Medical Center, Gainesville, Florida, USA
| | - Charles S Wingo
- Division of Nephrology, Hypertension and Renal Transplantation, Department of Medicine, University of Florida, Gainesville, Florida, USA
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida, USA
- Nephrology Section, Veteran Administration Medical Center, North Florida/South Georgia Malcom Randall Department of Veterans Affairs Medical Center, Gainesville, Florida, USA
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Assmus A, Mullins L, Ward M, Dobie R, Hunter R, Henderson NC, Mullins JJ. Loss of Adam10 Disrupts Ion Transport in Immortalized Kidney Collecting Duct Cells. FUNCTION 2021; 2:zqab024. [PMID: 34131651 PMCID: PMC8187228 DOI: 10.1093/function/zqab024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 04/23/2021] [Accepted: 04/27/2021] [Indexed: 01/06/2023] Open
Abstract
The kidney cortical collecting duct (CCD) comprises principal cells (PCs), intercalated cells (IC), and the recently discovered intermediate cell type. Kidney pathology in a mouse model of the syndrome of apparent aldosterone excess revealed plasticity of the CCD, with altered PC:intermediate cell:IC ratio. The self-immortalized mouse CCD cell line, mCCDcl1, shows functional characteristics of PCs, but displays a range of cell types, including intermediate cells, making it ideal to study plasticity. We knocked out Adam10, a key component of the Notch pathway, in mCCDcl1 cells, using CRISPR-Cas9 technology, and isolated independent clones, which exhibited severely affected sodium transport capacity and loss of aldosterone response. Single-cell RNA sequencing revealed significantly reduced expression of major PC-specific markers, such as Scnn1g (γ-ENaC) and Hsd11b2 (11βHSD2), but no significant changes in transcription of components of the Notch pathway were observed. Immunostaining in the knockout clone confirmed the decrease in expression of γ-ENaC and importantly, showed an altered, diffuse distribution of PC and IC markers, suggesting altered trafficking in the Adam10 knockout clone as an explanation for the loss of polarization.
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Affiliation(s)
- Adrienne Assmus
- University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Linda Mullins
- University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Mairi Ward
- University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Ross Dobie
- University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Robert Hunter
- University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Neil C Henderson
- University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - John J Mullins
- University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh EH16 4TJ, UK
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Ayuzawa N, Fujita T. The Mineralocorticoid Receptor in Salt-Sensitive Hypertension and Renal Injury. J Am Soc Nephrol 2021; 32:279-289. [PMID: 33397690 PMCID: PMC8054893 DOI: 10.1681/asn.2020071041] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Hypertension and its comorbidities pose a major public health problem associated with disease-associated factors related to a modern lifestyle, such high salt intake or obesity. Accumulating evidence has demonstrated that aldosterone and its receptor, the mineralocorticoid receptor (MR), have crucial roles in the development of salt-sensitive hypertension and coexisting cardiovascular and renal injuries. Accordingly, clinical trials have repetitively shown the promising effects of MR blockers in these diseases. We and other researchers have identified novel mechanisms of MR activation involved in salt-sensitive hypertension and renal injury, including the obesity-derived overproduction of aldosterone and ligand-independent signaling. Moreover, recent advances in the analysis of cell-specific and context-dependent mechanisms of MR activation in various tissues-including a classic target of aldosterone, aldosterone-sensitive distal nephrons-are now providing new insights. In this review, we summarize recent updates to our understanding of aldosterone-MR signaling, focusing on its role in salt-sensitive hypertension and renal injury.
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Affiliation(s)
- Nobuhiro Ayuzawa
- Division of Clinical Epigenetics, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Toshiro Fujita
- Division of Clinical Epigenetics, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan,Shinshu University School of Medicine, Nagano, Japan,Research Center for Social Systems, Shinshu University, Nagano, Japan
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Posaconazole-Induced Hypertension Masquerading as Congenital Adrenal Hyperplasia in a Child with Cystic Fibrosis. Case Rep Med 2020; 2020:8153012. [PMID: 32908540 PMCID: PMC7474764 DOI: 10.1155/2020/8153012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 08/17/2020] [Indexed: 12/31/2022] Open
Abstract
Background Deficiency of 11β-hydroxylase is the second most common cause of congenital adrenal hyperplasia (CAH), presenting with hypertension, hypokalaemia, precocious puberty, and adrenal insufficiency. We report the case of a 6-year-old boy with cystic fibrosis (CF) found to have hypertension and cortisol insufficiency, which were initially suspected to be due to CAH, but were subsequently identified as being secondary to posaconazole therapy. Case Presentation. A 6-year-old boy with CF was noted to have developed hypertension after administration of two doses of Orkambi™ (ivacaftor/lumacaftor), which was subsequently discontinued, but the hypertension persisted. Further investigations, including echocardiogram, abdominal Doppler, thyroid function, and urinary catecholamine levels, were normal. A urine steroid profile analysis raised the possibility of CAH due to 11β-hydroxylase deficiency, and a standard short synacthen test (SST) revealed suboptimal cortisol response. Clinically, there were no features of androgen excess. Detailed evaluation of the medical history revealed exposure to posaconazole for more than 2 months, and the hypertension had been noted to develop two weeks after the initiation of posaconazole. Hence, posaconazole was discontinued, following which the blood pressure, cortisol response to the SST, and urine steroid profile were normalized. Conclusion Posaconazole can induce a clinical and biochemical picture similar to CAH due to 11β-hydroxylase deficiency, which is reversible. It is prudent to monitor patients on posaconazole for cortisol insufficiency, hypertension, and electrolyte abnormalities.
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Sanchez-Niño MD, Ortiz A. Unravelling drug-induced hypertension: molecular mechanisms of aldosterone-independent mineralocorticoid receptor activation by posaconazole. Clin Kidney J 2018; 11:688-690. [PMID: 30289131 PMCID: PMC6165746 DOI: 10.1093/ckj/sfy087] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Indexed: 01/19/2023] Open
Abstract
Drug-induced hypertension offers the opportunity to further understand pathways involved in the regulation of blood pressure. Posaconazole is an antifungal agent known to induce hypertension and hypokalaemia. In recent months, a flurry of reports has unravelled the metabolic processes involved. In this issue of CKJ, Barton K, Davis TK, Marshall B et al. Posaconazole-induced hypertension and hypokalemia due to inhibition of the 11β-hydroxylase enzyme. Clin Kidney J 2018; 11: 691-693 present convincing evidence of 11β-hydroxylase inhibition resulting in a biochemical syndrome resembling genetic congenital adrenal hyperplasia and characterized by high 11-deoxycorticosterone and 11-deoxycortisol levels as well as androgen levels. This adds to prior evidence supporting inhibition of 11β-hydroxysteroid dehydrogenase 2, the enzyme that inactivates cortisol in aldosterone-sensitive tissues such as the kidneys, yielding a syndrome resembling genetic apparent mineralocorticoid excess or licorice toxicity, characterized by a high cortisol/cortisone ratio.
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Affiliation(s)
- Maria Dolores Sanchez-Niño
- IIS-Fundacion Jimenez Diaz, School of Medicine, Universidad Autonoma de Madrid; Fundacion Renal Iñigo Alvarez de Toledo-IRSIN and REDINREN, Madrid, Spain
| | - Alberto Ortiz
- IIS-Fundacion Jimenez Diaz, School of Medicine, Universidad Autonoma de Madrid; Fundacion Renal Iñigo Alvarez de Toledo-IRSIN and REDINREN, Madrid, Spain
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Abstract
The metabolic syndrome describes a clustering of risk factors—visceral obesity, dyslipidaemia, insulin resistance, and salt-sensitive hypertension—that increases mortality related to cardiovascular disease, type 2 diabetes, cancer, and non-alcoholic fatty liver disease. The prevalence of these concurrent comorbidities is ~ 25–30% worldwide, and metabolic syndrome therefore presents a significant global public health burden. Evidence from clinical and preclinical studies indicates that glucocorticoid excess is a key causal feature of metabolic syndrome. This is not increased systemic in circulating cortisol, rather increased bioavailability of active glucocorticoids within tissues. This review examines the role of covert glucocorticoid excess on the hypertension of the metabolic syndrome. Here, the role of the 11β-hydroxysteroid dehydrogenase enzymes, which exert intracrine and paracrine control over glucocorticoid signalling, is examined. 11βHSD1 amplifies glucocorticoid action in cells and contributes to hypertension through direct and indirect effects on the kidney and vasculature. The deactivation of glucocorticoid by 11βHSD2 controls ligand access to glucocorticoid and mineralocorticoid receptors: loss of function promotes salt retention and hypertension. As for hypertension in general, high blood pressure in the metabolic syndrome reflects a complex interaction between multiple systems. The clear association between high dietary salt, glucocorticoid production, and metabolic disorders has major relevance for human health and warrants systematic evaluation.
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Affiliation(s)
- Matthew A Bailey
- The British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK.
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Jiménez-Canino R, Lorenzo-Díaz F, Odermatt A, Bailey MA, Livingstone DEW, Jaisser F, Farman N, Alvarez de la Rosa D. 11β-HSD2 SUMOylation Modulates Cortisol-Induced Mineralocorticoid Receptor Nuclear Translocation Independently of Effects on Transactivation. Endocrinology 2017; 158:4047-4063. [PMID: 28938454 DOI: 10.1210/en.2017-00440] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 09/12/2017] [Indexed: 12/26/2022]
Abstract
The enzyme 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) has an essential role in aldosterone target tissues, conferring aldosterone selectivity for the mineralocorticoid receptor (MR) by converting 11β-hydroxyglucocorticoids to inactive 11-ketosteroids. Congenital deficiency of 11β-HSD2 causes a form of salt-sensitive hypertension known as the syndrome of apparent mineralocorticoid excess. The disease phenotype, which ranges from mild to severe, correlates well with reduction in enzyme activity. Furthermore, polymorphisms in the 11β-HSD2 coding gene (HSD11B2) have been linked to high blood pressure and salt sensitivity, major cardiovascular risk factors. 11β-HSD2 expression is controlled by different factors such as cytokines, sex steroids, or vasopressin, but posttranslational modulation of its activity has not been explored. Analysis of 11β-HSD2 sequence revealed a consensus site for conjugation of small ubiquitin-related modifier (SUMO) peptide, a major posttranslational regulatory event in several cellular processes. Our results demonstrate that 11β-HSD2 is SUMOylated at lysine 266. Non-SUMOylatable mutant K266R showed slightly higher substrate affinity and decreased Vmax, but no effects on protein stability or subcellular localization. Despite mild changes in enzyme activity, mutant K266R was unable to prevent cortisol-dependent MR nuclear translocation. The same effect was achieved by coexpression of wild-type 11β-HSD2 with sentrin-specific protease 1, a protease that catalyzes SUMO deconjugation. In the presence of 11β-HSD2-K266R, increased nuclear MR localization did not correlate with increased response to cortisol or increased recruitment of transcriptional coregulators. Taken together, our data suggests that SUMOylation of 11β-HSD2 at residue K266 modulates cortisol-mediated MR nuclear translocation independently of effects on transactivation.
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Affiliation(s)
- Rubén Jiménez-Canino
- Department of Basic Medical Sciences, Institute of Biomedical Technologies and Center for Biomedical Research of the Canary Islands, Universidad de La Laguna, 38200 Tenerife, Spain
| | - Fabián Lorenzo-Díaz
- Department of Basic Medical Sciences, Institute of Biomedical Technologies and Center for Biomedical Research of the Canary Islands, Universidad de La Laguna, 38200 Tenerife, Spain
| | - Alex Odermatt
- Division of Molecular and Systems Toxicology, Department of Pharmaceutical Sciences, University of Basel, 4056 Basel, Switzerland
| | - Matthew A Bailey
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh EH16 4TJ, United Kingdom
| | - Dawn E W Livingstone
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh EH16 4TJ, United Kingdom
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH16 4TJ, United Kingdom
| | - Frederic Jaisser
- INSERM UMRS 1138, Team 1, Centre de Recherche des Cordeliers, Université Pierre et Marie Curie, 75006 Paris, France
| | - Nicolette Farman
- INSERM UMRS 1138, Team 1, Centre de Recherche des Cordeliers, Université Pierre et Marie Curie, 75006 Paris, France
| | - Diego Alvarez de la Rosa
- Department of Basic Medical Sciences, Institute of Biomedical Technologies and Center for Biomedical Research of the Canary Islands, Universidad de La Laguna, 38200 Tenerife, Spain
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Ueda K, Nishimoto M, Hirohama D, Ayuzawa N, Kawarazaki W, Watanabe A, Shimosawa T, Loffing J, Zhang MZ, Marumo T, Fujita T. Renal Dysfunction Induced by Kidney-Specific Gene Deletion of Hsd11b2 as a Primary Cause of Salt-Dependent Hypertension. Hypertension 2017; 70:111-118. [PMID: 28559392 DOI: 10.1161/hypertensionaha.116.08966] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 03/31/2017] [Accepted: 04/10/2017] [Indexed: 01/21/2023]
Abstract
Genome-wide analysis of renal sodium-transporting system has identified specific variations of Mendelian hypertensive disorders, including HSD11B2 gene variants in apparent mineralocorticoid excess. However, these genetic variations in extrarenal tissue can be involved in developing hypertension, as demonstrated in former studies using global and brain-specific Hsd11b2 knockout rodents. To re-examine the importance of renal dysfunction on developing hypertension, we generated kidney-specific Hsd11b2 knockout mice. The knockout mice exhibited systemic hypertension, which was abolished by reducing salt intake, suggesting its salt-dependency. In addition, we detected an increase in renal membrane expressions of cleaved epithelial sodium channel-α and T53-phosphorylated Na+-Cl- cotransporter in the knockout mice. Acute intraperitoneal administration of amiloride-induced natriuresis and increased urinary sodium/potassium ratio more in the knockout mice compared with those in the wild-type control mice. Chronic administration of amiloride and high-KCl diet significantly decreased mean blood pressure in the knockout mice, which was accompanied with the correction of hypokalemia and the resultant decrease in Na+-Cl- cotransporter phosphorylation. Accordingly, a Na+-Cl- cotransporter blocker hydrochlorothiazide significantly decreased mean blood pressure in the knockout mice. Chronic administration of mineralocorticoid receptor antagonist spironolactone significantly decreased mean blood pressure of the knockout mice along with downregulation of cleaved epithelial sodium channel-α and phosphorylated Na+-Cl- cotransporter expression in the knockout kidney. Our data suggest that kidney-specific deficiency of 11β-HSD2 leads to salt-dependent hypertension, which is attributed to mineralocorticoid receptor-epithelial sodium channel-Na+-Cl- cotransporter activation in the kidney, and provides evidence that renal dysfunction is essential for developing the phenotype of apparent mineralocorticoid excess.
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Affiliation(s)
- Kohei Ueda
- From the Division of Clinical Epigenetics, Research Center of Advanced Science and Technology, The University of Tokyo, Japan (K.U., M.N., D.H., N.A., W.K., A.W., T.M., T.F.); Department of Clinical Laboratory, International University of Health and Welfare, School of Medicine, Tokyo, Japan (T.S.); CREST, Japan Agency for Medical Research and Development (AMED), Tokyo (T.S., T.M., T.F.); National Center of Competence in Research 'Kidney Control of Homeostasis', Zurich, Switzerland (J.L.); Institute of Anatomy, University of Zurich, Switzerland (J.L.); Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN (M.-Z.Z.); and Department of Nephrology and Endocrinology, National Defense Medical College, Saitama, Japan (A.W.).
| | - Mitsuhiro Nishimoto
- From the Division of Clinical Epigenetics, Research Center of Advanced Science and Technology, The University of Tokyo, Japan (K.U., M.N., D.H., N.A., W.K., A.W., T.M., T.F.); Department of Clinical Laboratory, International University of Health and Welfare, School of Medicine, Tokyo, Japan (T.S.); CREST, Japan Agency for Medical Research and Development (AMED), Tokyo (T.S., T.M., T.F.); National Center of Competence in Research 'Kidney Control of Homeostasis', Zurich, Switzerland (J.L.); Institute of Anatomy, University of Zurich, Switzerland (J.L.); Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN (M.-Z.Z.); and Department of Nephrology and Endocrinology, National Defense Medical College, Saitama, Japan (A.W.)
| | - Daigoro Hirohama
- From the Division of Clinical Epigenetics, Research Center of Advanced Science and Technology, The University of Tokyo, Japan (K.U., M.N., D.H., N.A., W.K., A.W., T.M., T.F.); Department of Clinical Laboratory, International University of Health and Welfare, School of Medicine, Tokyo, Japan (T.S.); CREST, Japan Agency for Medical Research and Development (AMED), Tokyo (T.S., T.M., T.F.); National Center of Competence in Research 'Kidney Control of Homeostasis', Zurich, Switzerland (J.L.); Institute of Anatomy, University of Zurich, Switzerland (J.L.); Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN (M.-Z.Z.); and Department of Nephrology and Endocrinology, National Defense Medical College, Saitama, Japan (A.W.)
| | - Nobuhiro Ayuzawa
- From the Division of Clinical Epigenetics, Research Center of Advanced Science and Technology, The University of Tokyo, Japan (K.U., M.N., D.H., N.A., W.K., A.W., T.M., T.F.); Department of Clinical Laboratory, International University of Health and Welfare, School of Medicine, Tokyo, Japan (T.S.); CREST, Japan Agency for Medical Research and Development (AMED), Tokyo (T.S., T.M., T.F.); National Center of Competence in Research 'Kidney Control of Homeostasis', Zurich, Switzerland (J.L.); Institute of Anatomy, University of Zurich, Switzerland (J.L.); Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN (M.-Z.Z.); and Department of Nephrology and Endocrinology, National Defense Medical College, Saitama, Japan (A.W.)
| | - Wakako Kawarazaki
- From the Division of Clinical Epigenetics, Research Center of Advanced Science and Technology, The University of Tokyo, Japan (K.U., M.N., D.H., N.A., W.K., A.W., T.M., T.F.); Department of Clinical Laboratory, International University of Health and Welfare, School of Medicine, Tokyo, Japan (T.S.); CREST, Japan Agency for Medical Research and Development (AMED), Tokyo (T.S., T.M., T.F.); National Center of Competence in Research 'Kidney Control of Homeostasis', Zurich, Switzerland (J.L.); Institute of Anatomy, University of Zurich, Switzerland (J.L.); Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN (M.-Z.Z.); and Department of Nephrology and Endocrinology, National Defense Medical College, Saitama, Japan (A.W.)
| | - Atsushi Watanabe
- From the Division of Clinical Epigenetics, Research Center of Advanced Science and Technology, The University of Tokyo, Japan (K.U., M.N., D.H., N.A., W.K., A.W., T.M., T.F.); Department of Clinical Laboratory, International University of Health and Welfare, School of Medicine, Tokyo, Japan (T.S.); CREST, Japan Agency for Medical Research and Development (AMED), Tokyo (T.S., T.M., T.F.); National Center of Competence in Research 'Kidney Control of Homeostasis', Zurich, Switzerland (J.L.); Institute of Anatomy, University of Zurich, Switzerland (J.L.); Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN (M.-Z.Z.); and Department of Nephrology and Endocrinology, National Defense Medical College, Saitama, Japan (A.W.)
| | - Tatsuo Shimosawa
- From the Division of Clinical Epigenetics, Research Center of Advanced Science and Technology, The University of Tokyo, Japan (K.U., M.N., D.H., N.A., W.K., A.W., T.M., T.F.); Department of Clinical Laboratory, International University of Health and Welfare, School of Medicine, Tokyo, Japan (T.S.); CREST, Japan Agency for Medical Research and Development (AMED), Tokyo (T.S., T.M., T.F.); National Center of Competence in Research 'Kidney Control of Homeostasis', Zurich, Switzerland (J.L.); Institute of Anatomy, University of Zurich, Switzerland (J.L.); Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN (M.-Z.Z.); and Department of Nephrology and Endocrinology, National Defense Medical College, Saitama, Japan (A.W.)
| | - Johannes Loffing
- From the Division of Clinical Epigenetics, Research Center of Advanced Science and Technology, The University of Tokyo, Japan (K.U., M.N., D.H., N.A., W.K., A.W., T.M., T.F.); Department of Clinical Laboratory, International University of Health and Welfare, School of Medicine, Tokyo, Japan (T.S.); CREST, Japan Agency for Medical Research and Development (AMED), Tokyo (T.S., T.M., T.F.); National Center of Competence in Research 'Kidney Control of Homeostasis', Zurich, Switzerland (J.L.); Institute of Anatomy, University of Zurich, Switzerland (J.L.); Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN (M.-Z.Z.); and Department of Nephrology and Endocrinology, National Defense Medical College, Saitama, Japan (A.W.)
| | - Ming-Zhi Zhang
- From the Division of Clinical Epigenetics, Research Center of Advanced Science and Technology, The University of Tokyo, Japan (K.U., M.N., D.H., N.A., W.K., A.W., T.M., T.F.); Department of Clinical Laboratory, International University of Health and Welfare, School of Medicine, Tokyo, Japan (T.S.); CREST, Japan Agency for Medical Research and Development (AMED), Tokyo (T.S., T.M., T.F.); National Center of Competence in Research 'Kidney Control of Homeostasis', Zurich, Switzerland (J.L.); Institute of Anatomy, University of Zurich, Switzerland (J.L.); Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN (M.-Z.Z.); and Department of Nephrology and Endocrinology, National Defense Medical College, Saitama, Japan (A.W.)
| | - Takeshi Marumo
- From the Division of Clinical Epigenetics, Research Center of Advanced Science and Technology, The University of Tokyo, Japan (K.U., M.N., D.H., N.A., W.K., A.W., T.M., T.F.); Department of Clinical Laboratory, International University of Health and Welfare, School of Medicine, Tokyo, Japan (T.S.); CREST, Japan Agency for Medical Research and Development (AMED), Tokyo (T.S., T.M., T.F.); National Center of Competence in Research 'Kidney Control of Homeostasis', Zurich, Switzerland (J.L.); Institute of Anatomy, University of Zurich, Switzerland (J.L.); Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN (M.-Z.Z.); and Department of Nephrology and Endocrinology, National Defense Medical College, Saitama, Japan (A.W.)
| | - Toshiro Fujita
- From the Division of Clinical Epigenetics, Research Center of Advanced Science and Technology, The University of Tokyo, Japan (K.U., M.N., D.H., N.A., W.K., A.W., T.M., T.F.); Department of Clinical Laboratory, International University of Health and Welfare, School of Medicine, Tokyo, Japan (T.S.); CREST, Japan Agency for Medical Research and Development (AMED), Tokyo (T.S., T.M., T.F.); National Center of Competence in Research 'Kidney Control of Homeostasis', Zurich, Switzerland (J.L.); Institute of Anatomy, University of Zurich, Switzerland (J.L.); Division of Nephrology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN (M.-Z.Z.); and Department of Nephrology and Endocrinology, National Defense Medical College, Saitama, Japan (A.W.).
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11
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Mansley MK, Watt GB, Francis SL, Walker DJ, Land SC, Bailey MA, Wilson SM. Dexamethasone and insulin activate serum and glucocorticoid-inducible kinase 1 (SGK1) via different molecular mechanisms in cortical collecting duct cells. Physiol Rep 2016; 4:4/10/e12792. [PMID: 27225626 PMCID: PMC4886164 DOI: 10.14814/phy2.12792] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 03/29/2016] [Indexed: 01/12/2023] Open
Abstract
Serum and glucocorticoid-inducible kinase 1 (SGK1) is a protein kinase that contributes to the hormonal control of renal Na(+) retention by regulating the abundance of epithelial Na(+) channels (ENaC) at the apical surface of the principal cells of the cortical collecting duct (CCD). Although glucocorticoids and insulin stimulate Na(+) transport by activating SGK1, the responses follow different time courses suggesting that these hormones act by different mechanisms. We therefore explored the signaling pathways that allow dexamethasone and insulin to stimulate Na(+) transport in mouse CCD cells (mpkCCDcl4). Dexamethasone evoked a progressive augmentation of electrogenic Na(+) transport that became apparent after ~45 min latency and was associated with increases in SGK1 activity and abundance and with increased expression of SGK1 mRNA Although the catalytic activity of SGK1 is maintained by phosphatidylinositol-OH-3-kinase (PI3K), dexamethasone had no effect upon PI3K activity. Insulin also stimulated Na(+) transport but this response occurred with no discernible latency. Moreover, although insulin also activated SGK1, it had no effect upon SGK1 protein or mRNA abundance. Insulin did, however, evoke a clear increase in cellular PI3K activity. Our data are consistent with earlier work, which shows that glucocorticoids regulate Na(+) retention by inducing sgk1 gene expression, and also establish that this occurs independently of increased PI3K activity. Insulin, on the other hand, stimulates Na(+) transport via a mechanism independent of sgk1 gene expression that involves PI3K activation. Although both hormones act via SGK1, our data show that they activate this kinase by distinct physiological mechanisms.
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Affiliation(s)
- Morag K Mansley
- Division of Pharmacy, School of Medicine, Pharmacy and Health, Durham University Queen's Campus, Stockton-on-Tees, UK
| | - Gordon B Watt
- Medical Research Institute, College of Medicine, Dentistry and Nursing, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
| | - Sarah L Francis
- Division of Pharmacy, School of Medicine, Pharmacy and Health, Durham University Queen's Campus, Stockton-on-Tees, UK
| | - David J Walker
- Medical Research Institute, College of Medicine, Dentistry and Nursing, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
| | - Stephen C Land
- Medical Research Institute, College of Medicine, Dentistry and Nursing, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
| | - Matthew A Bailey
- The British Heart Foundation Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Stuart M Wilson
- Division of Pharmacy, School of Medicine, Pharmacy and Health, Durham University Queen's Campus, Stockton-on-Tees, UK
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12
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Mansley MK, Ivy JR, Bailey MA. ISN Forefronts Symposium 2015: The Evolution of Hypertension-Old Genes, New Concepts. Kidney Int Rep 2016; 1:197-203. [PMID: 27722209 PMCID: PMC5044930 DOI: 10.1016/j.ekir.2016.08.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 07/26/2016] [Accepted: 08/02/2016] [Indexed: 12/17/2022] Open
Abstract
Hypertension is known as the “silent killer,” driving the global public health burden of cardiovascular and renal disease. Blood pressure homeostasis is intimately associated with sodium balance and the distribution of sodium between fluid compartments and within tissues. On a population level, most societies consume 10 times more salt that the 0.5 g required by physiological need. This high salt intake is strongly linked to hypertension and to the World Health Organization targeting a ∼30% relative reduction in mean population salt intake to arrest the global mortality due to cardiovascular disease. But how does a habitually high-salt diet cause blood pressure to rise? In this focused review, we discuss 2 “evolutionary medicine” concepts, presented at the ISN Forefront Meeting “Immunomodulation of Cardio-renal Function.” We first examine how ancestral variants in genes that conferred a selection advantage during early human development are now maladaptive. We then discuss the conservation of “renal” sodium transport processes across multiple organ systems, including the brain. These systems influence sodium appetite and can exert an often-overlooked effect on long-term blood pressure control.
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Affiliation(s)
- Morag K Mansley
- The British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK
| | - Jessica R Ivy
- The British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK
| | - Matthew A Bailey
- The British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK
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13
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Morris RC, Schmidlin O, Sebastian A, Tanaka M, Kurtz TW. Vasodysfunction That Involves Renal Vasodysfunction, Not Abnormally Increased Renal Retention of Sodium, Accounts for the Initiation of Salt-Induced Hypertension. Circulation 2016; 133:881-93. [PMID: 26927006 DOI: 10.1161/circulationaha.115.017923] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- R Curtis Morris
- From the Departments of Medicine (R.C.M., O.S., A.S., M.T.) and Laboratory Medicine (T.W.K.), University of California, San Francisco.
| | - Olga Schmidlin
- From the Departments of Medicine (R.C.M., O.S., A.S., M.T.) and Laboratory Medicine (T.W.K.), University of California, San Francisco
| | - Anthony Sebastian
- From the Departments of Medicine (R.C.M., O.S., A.S., M.T.) and Laboratory Medicine (T.W.K.), University of California, San Francisco
| | - Masae Tanaka
- From the Departments of Medicine (R.C.M., O.S., A.S., M.T.) and Laboratory Medicine (T.W.K.), University of California, San Francisco
| | - Theodore W Kurtz
- From the Departments of Medicine (R.C.M., O.S., A.S., M.T.) and Laboratory Medicine (T.W.K.), University of California, San Francisco.
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14
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Evans LC, Ivy JR, Wyrwoll C, McNairn JA, Menzies RI, Christensen TH, Al-Dujaili EAS, Kenyon CJ, Mullins JJ, Seckl JR, Holmes MC, Bailey MA. Conditional Deletion of Hsd11b2 in the Brain Causes Salt Appetite and Hypertension. Circulation 2016; 133:1360-70. [PMID: 26951843 PMCID: PMC4819772 DOI: 10.1161/circulationaha.115.019341] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 02/12/2016] [Indexed: 11/30/2022]
Abstract
Supplemental Digital Content is available in the text. Background— The hypertensive syndrome of Apparent Mineralocorticoid Excess is caused by loss-of-function mutations in the gene encoding 11β-hydroxysteroid dehydrogenase type 2 (11βHSD2), allowing inappropriate activation of the mineralocorticoid receptor by endogenous glucocorticoid. Hypertension is attributed to sodium retention in the distal nephron, but 11βHSD2 is also expressed in the brain. However, the central contribution to Apparent Mineralocorticoid Excess and other hypertensive states is often overlooked and is unresolved. We therefore used a Cre-Lox strategy to generate 11βHSD2 brain-specific knockout (Hsd11b2.BKO) mice, measuring blood pressure and salt appetite in adults. Methods and Results— Basal blood pressure, electrolytes, and circulating corticosteroids were unaffected in Hsd11b2.BKO mice. When offered saline to drink, Hsd11b2.BKO mice consumed 3 times more sodium than controls and became hypertensive. Salt appetite was inhibited by spironolactone. Control mice fed the same daily sodium intake remained normotensive, showing the intrinsic salt resistance of the background strain. Dexamethasone suppressed endogenous glucocorticoid and abolished the salt-induced blood pressure differential between genotypes. Salt sensitivity in Hsd11b2.BKO mice was not caused by impaired renal sodium excretion or volume expansion; pressor responses to phenylephrine were enhanced and baroreflexes impaired in these animals. Conclusions— Reduced 11βHSD2 activity in the brain does not intrinsically cause hypertension, but it promotes a hunger for salt and a transition from salt resistance to salt sensitivity. Our data suggest that 11βHSD2-positive neurons integrate salt appetite and the blood pressure response to dietary sodium through a mineralocorticoid receptor–dependent pathway. Therefore, central mineralocorticoid receptor antagonism could increase compliance to low-sodium regimens and help blood pressure management in cardiovascular disease.
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Affiliation(s)
- Louise C Evans
- From British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, United Kingdom (L.C.E., J.R.I., C.W., J.A.M., R.I.M., T.H.C., C.J.K., J.J.M., J.R.S., M.C.H., M.A.B.); and Dietetics, Nutrition and Biological Sciences Department, Queen Margaret University, Edinburgh, United Kingdom (E.A.S.Al-D.). The current address for Dr Evans is Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee; the current address for Dr Wyrwoll is School of Anatomy, Physiology & Human Biology, The University of Western Australia, Crawley, Australia; and the current address for Dr Christensen is Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense
| | - Jessica R Ivy
- From British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, United Kingdom (L.C.E., J.R.I., C.W., J.A.M., R.I.M., T.H.C., C.J.K., J.J.M., J.R.S., M.C.H., M.A.B.); and Dietetics, Nutrition and Biological Sciences Department, Queen Margaret University, Edinburgh, United Kingdom (E.A.S.Al-D.). The current address for Dr Evans is Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee; the current address for Dr Wyrwoll is School of Anatomy, Physiology & Human Biology, The University of Western Australia, Crawley, Australia; and the current address for Dr Christensen is Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense
| | - Caitlin Wyrwoll
- From British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, United Kingdom (L.C.E., J.R.I., C.W., J.A.M., R.I.M., T.H.C., C.J.K., J.J.M., J.R.S., M.C.H., M.A.B.); and Dietetics, Nutrition and Biological Sciences Department, Queen Margaret University, Edinburgh, United Kingdom (E.A.S.Al-D.). The current address for Dr Evans is Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee; the current address for Dr Wyrwoll is School of Anatomy, Physiology & Human Biology, The University of Western Australia, Crawley, Australia; and the current address for Dr Christensen is Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense
| | - Julie A McNairn
- From British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, United Kingdom (L.C.E., J.R.I., C.W., J.A.M., R.I.M., T.H.C., C.J.K., J.J.M., J.R.S., M.C.H., M.A.B.); and Dietetics, Nutrition and Biological Sciences Department, Queen Margaret University, Edinburgh, United Kingdom (E.A.S.Al-D.). The current address for Dr Evans is Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee; the current address for Dr Wyrwoll is School of Anatomy, Physiology & Human Biology, The University of Western Australia, Crawley, Australia; and the current address for Dr Christensen is Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense
| | - Robert I Menzies
- From British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, United Kingdom (L.C.E., J.R.I., C.W., J.A.M., R.I.M., T.H.C., C.J.K., J.J.M., J.R.S., M.C.H., M.A.B.); and Dietetics, Nutrition and Biological Sciences Department, Queen Margaret University, Edinburgh, United Kingdom (E.A.S.Al-D.). The current address for Dr Evans is Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee; the current address for Dr Wyrwoll is School of Anatomy, Physiology & Human Biology, The University of Western Australia, Crawley, Australia; and the current address for Dr Christensen is Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense
| | - Thorbjørn H Christensen
- From British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, United Kingdom (L.C.E., J.R.I., C.W., J.A.M., R.I.M., T.H.C., C.J.K., J.J.M., J.R.S., M.C.H., M.A.B.); and Dietetics, Nutrition and Biological Sciences Department, Queen Margaret University, Edinburgh, United Kingdom (E.A.S.Al-D.). The current address for Dr Evans is Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee; the current address for Dr Wyrwoll is School of Anatomy, Physiology & Human Biology, The University of Western Australia, Crawley, Australia; and the current address for Dr Christensen is Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense
| | - Emad A S Al-Dujaili
- From British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, United Kingdom (L.C.E., J.R.I., C.W., J.A.M., R.I.M., T.H.C., C.J.K., J.J.M., J.R.S., M.C.H., M.A.B.); and Dietetics, Nutrition and Biological Sciences Department, Queen Margaret University, Edinburgh, United Kingdom (E.A.S.Al-D.). The current address for Dr Evans is Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee; the current address for Dr Wyrwoll is School of Anatomy, Physiology & Human Biology, The University of Western Australia, Crawley, Australia; and the current address for Dr Christensen is Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense
| | - Christopher J Kenyon
- From British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, United Kingdom (L.C.E., J.R.I., C.W., J.A.M., R.I.M., T.H.C., C.J.K., J.J.M., J.R.S., M.C.H., M.A.B.); and Dietetics, Nutrition and Biological Sciences Department, Queen Margaret University, Edinburgh, United Kingdom (E.A.S.Al-D.). The current address for Dr Evans is Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee; the current address for Dr Wyrwoll is School of Anatomy, Physiology & Human Biology, The University of Western Australia, Crawley, Australia; and the current address for Dr Christensen is Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense
| | - John J Mullins
- From British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, United Kingdom (L.C.E., J.R.I., C.W., J.A.M., R.I.M., T.H.C., C.J.K., J.J.M., J.R.S., M.C.H., M.A.B.); and Dietetics, Nutrition and Biological Sciences Department, Queen Margaret University, Edinburgh, United Kingdom (E.A.S.Al-D.). The current address for Dr Evans is Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee; the current address for Dr Wyrwoll is School of Anatomy, Physiology & Human Biology, The University of Western Australia, Crawley, Australia; and the current address for Dr Christensen is Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense
| | - Jonathan R Seckl
- From British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, United Kingdom (L.C.E., J.R.I., C.W., J.A.M., R.I.M., T.H.C., C.J.K., J.J.M., J.R.S., M.C.H., M.A.B.); and Dietetics, Nutrition and Biological Sciences Department, Queen Margaret University, Edinburgh, United Kingdom (E.A.S.Al-D.). The current address for Dr Evans is Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee; the current address for Dr Wyrwoll is School of Anatomy, Physiology & Human Biology, The University of Western Australia, Crawley, Australia; and the current address for Dr Christensen is Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense
| | - Megan C Holmes
- From British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, United Kingdom (L.C.E., J.R.I., C.W., J.A.M., R.I.M., T.H.C., C.J.K., J.J.M., J.R.S., M.C.H., M.A.B.); and Dietetics, Nutrition and Biological Sciences Department, Queen Margaret University, Edinburgh, United Kingdom (E.A.S.Al-D.). The current address for Dr Evans is Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee; the current address for Dr Wyrwoll is School of Anatomy, Physiology & Human Biology, The University of Western Australia, Crawley, Australia; and the current address for Dr Christensen is Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense
| | - Matthew A Bailey
- From British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, United Kingdom (L.C.E., J.R.I., C.W., J.A.M., R.I.M., T.H.C., C.J.K., J.J.M., J.R.S., M.C.H., M.A.B.); and Dietetics, Nutrition and Biological Sciences Department, Queen Margaret University, Edinburgh, United Kingdom (E.A.S.Al-D.). The current address for Dr Evans is Department of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee; the current address for Dr Wyrwoll is School of Anatomy, Physiology & Human Biology, The University of Western Australia, Crawley, Australia; and the current address for Dr Christensen is Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense.
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15
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Mullins LJ, Kenyon CJ, Bailey MA, Conway BR, Diaz ME, Mullins JJ. Mineralocorticoid Excess or Glucocorticoid Insufficiency: Renal and Metabolic Phenotypes in a Rat Hsd11b2 Knockout Model. Hypertension 2015; 66:667-73. [PMID: 26077568 PMCID: PMC4847935 DOI: 10.1161/hypertensionaha.115.05262] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 05/27/2015] [Indexed: 01/06/2023]
Abstract
Obesity and hypertension are 2 major health issues of the 21st century. The syndrome of apparent mineralocorticoid excess is caused by deficiency of 11β-hydroxysteroid dehydrogenase type 2 (Hsd11b2), which normally inactivates glucocorticoids, rendering the mineralocorticoid receptor aldosterone–specific. The metabolic consequences of Hsd11b2 knockout in the rat are investigated in parallel with electrolyte homeostasis. Hsd11b2 was knocked out, by pronuclear microinjection of targeted zinc-finger nuclease mRNAs, and 1 line was characterized for its response to renal and metabolic challenges. Plasma 11-dehydrocorticosterone was below detection thresholds, and Hsd11b2 protein was undetected by Western blot, indicating complete ablation. Homozygotes were 13% smaller than wild-type littermates, and were polydipsic and polyuric. Their kidneys, adrenals, and hearts were significantly enlarged, but mesenteric fat pads and liver were significantly smaller. On a 0.3% Na diet, mean arterial blood pressure was ≈65 mm Hg higher than controls but only 25 mm Hg higher on a 0.03% Na+ diet. Urinary Na/K ratio of homozygotes was similar to controls on 0.3% Na+ diet but urinary albumin and calcium were elevated. Corticosterone and aldosterone levels showed normal circadian variation on both a 0.3% and 0.03% Na+ diet, but plasma renin was suppressed in homozygotes on both diets. Plasma glucose responses to an oral glucose challenge were reduced despite low circulating insulin, indicating much greater sensitivity to insulin in homozygotes. The rat model reveals mechanisms linking electrolyte homeostasis and metabolic control through the restriction of Hsd11b1 substrate availability.
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Affiliation(s)
- Linda J Mullins
- From the Molecular Physiology Laboratory, University of Edinburgh/BHF Centre for Cardiovascular Science, Queen's Medical Research Institute, Edinburgh, United Kingdom.
| | - Christopher J Kenyon
- From the Molecular Physiology Laboratory, University of Edinburgh/BHF Centre for Cardiovascular Science, Queen's Medical Research Institute, Edinburgh, United Kingdom
| | - Matthew A Bailey
- From the Molecular Physiology Laboratory, University of Edinburgh/BHF Centre for Cardiovascular Science, Queen's Medical Research Institute, Edinburgh, United Kingdom
| | - Bryan R Conway
- From the Molecular Physiology Laboratory, University of Edinburgh/BHF Centre for Cardiovascular Science, Queen's Medical Research Institute, Edinburgh, United Kingdom
| | - Mary E Diaz
- From the Molecular Physiology Laboratory, University of Edinburgh/BHF Centre for Cardiovascular Science, Queen's Medical Research Institute, Edinburgh, United Kingdom
| | - John J Mullins
- From the Molecular Physiology Laboratory, University of Edinburgh/BHF Centre for Cardiovascular Science, Queen's Medical Research Institute, Edinburgh, United Kingdom
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16
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Hunter RW, Bailey MA. Glucocorticoids and 11β-hydroxysteroid dehydrogenases: mechanisms for hypertension. Curr Opin Pharmacol 2015; 21:105-14. [DOI: 10.1016/j.coph.2015.01.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 01/20/2015] [Accepted: 01/22/2015] [Indexed: 11/26/2022]
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17
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Verouti SN, Boscardin E, Hummler E, Frateschi S. Regulation of blood pressure and renal function by NCC and ENaC: lessons from genetically engineered mice. Curr Opin Pharmacol 2015; 21:60-72. [PMID: 25613995 DOI: 10.1016/j.coph.2014.12.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 12/22/2014] [Accepted: 12/22/2014] [Indexed: 01/01/2023]
Abstract
The activity of the thiazide-sensitive Na(+)/Cl(-) cotransporter (NCC) and of the amiloride-sensitive epithelial Na(+) channel (ENaC) is pivotal for blood pressure regulation. NCC is responsible for Na(+) reabsorption in the distal convoluted tubule (DCT) of the nephron, while ENaC reabsorbs the filtered Na(+) in the late DCT and in the cortical collecting ducts (CCD) providing the final renal adjustment to Na(+) balance. Here, we aim to highlight the recent advances made using transgenic mouse models towards the understanding of the regulation of NCC and ENaC function relevant to the control of sodium balance and blood pressure. We thus like to pave the way for common mechanisms regulating these two sodium-transporting proteins and their potential implication in structural remodeling of the nephron segments and Na(+) and Cl(-) reabsorption.
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Affiliation(s)
- Sophia N Verouti
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
| | - Emilie Boscardin
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
| | - Edith Hummler
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland.
| | - Simona Frateschi
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland.
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18
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Hunter RW, Ivy JR, Flatman PW, Kenyon CJ, Craigie E, Mullins LJ, Bailey MA, Mullins JJ. Hypertrophy in the Distal Convoluted Tubule of an 11β-Hydroxysteroid Dehydrogenase Type 2 Knockout Model. J Am Soc Nephrol 2014; 26:1537-48. [PMID: 25349206 DOI: 10.1681/asn.2013060634] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 08/12/2014] [Indexed: 11/03/2022] Open
Abstract
Na(+) transport in the renal distal convoluted tubule (DCT) by the thiazide-sensitive NaCl cotransporter (NCC) is a major determinant of total body Na(+) and BP. NCC-mediated transport is stimulated by aldosterone, the dominant regulator of chronic Na(+) homeostasis, but the mechanism is controversial. Transport may also be affected by epithelial remodeling, which occurs in the DCT in response to chronic perturbations in electrolyte homeostasis. Hsd11b2(-/-) mice, which lack the enzyme 11β-hydroxysteroid dehydrogenase type 2 (11βHSD2) and thus exhibit the syndrome of apparent mineralocorticoid excess, provided an ideal model in which to investigate the potential for DCT hypertrophy to contribute to Na(+) retention in a hypertensive condition. The DCTs of Hsd11b2(-/-) mice exhibited hypertrophy and hyperplasia and the kidneys expressed higher levels of total and phosphorylated NCC compared with those of wild-type mice. However, the striking structural and molecular phenotypes were not associated with an increase in the natriuretic effect of thiazide. In wild-type mice, Hsd11b2 mRNA was detected in some tubule segments expressing Slc12a3, but 11βHSD2 and NCC did not colocalize at the protein level. Thus, the phosphorylation status of NCC may not necessarily equate to its activity in vivo, and the structural remodeling of the DCT in the knockout mouse may not be a direct consequence of aberrant corticosteroid signaling in DCT cells. These observations suggest that the conventional concept of mineralocorticoid signaling in the DCT should be revised to recognize the complexity of NCC regulation by corticosteroids.
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Affiliation(s)
- Robert W Hunter
- British Heart Foundation Centre for Cardiovascular Science and
| | - Jessica R Ivy
- British Heart Foundation Centre for Cardiovascular Science and
| | - Peter W Flatman
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, United Kingdom
| | | | - Eilidh Craigie
- British Heart Foundation Centre for Cardiovascular Science and
| | - Linda J Mullins
- British Heart Foundation Centre for Cardiovascular Science and
| | | | - John J Mullins
- British Heart Foundation Centre for Cardiovascular Science and
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19
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Ivy JR, Bailey MA. Pressure natriuresis and the renal control of arterial blood pressure. J Physiol 2014; 592:3955-67. [PMID: 25107929 DOI: 10.1113/jphysiol.2014.271676] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The regulation of extracellular fluid volume by renal sodium excretion lies at the centre of blood pressure homeostasis. Renal perfusion pressure can directly regulate sodium reabsorption in the proximal tubule. This acute pressure natriuresis response is a uniquely powerful means of stabilizing long-term blood pressure around a set point. By logical extension, deviation from the set point can only be sustained if the pressure natriuresis mechanism is impaired, suggesting that hypertension is caused or sustained by a defect in the relationship between renal perfusion pressure and sodium excretion. Here we describe the role of pressure natriuresis in blood pressure control and outline the cascade of biophysical and paracrine events in the renal medulla that integrate the vascular and tubular response to altered perfusion pressure. Pressure natriuresis is impaired in hypertension and mechanistic insight into dysfunction comes from genetic analysis of blood pressure disorders. Transplantation studies in rats show that blood pressure is determined by the genotype of the kidney and Mendelian hypertension indicates that the distal nephron influences the overall natriuretic efficiency. These approaches and the outcomes of genome-wide-association studies broaden our view of blood pressure control, suggesting that renal sympathetic nerve activity and local inflammation can impair pressure natriuresis to cause hypertension. Understanding how these systems interact is necessary to tackle the global burden of hypertension.
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Affiliation(s)
- Jessica R Ivy
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Matthew A Bailey
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
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20
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Hunter RW, Ivy JR, Bailey MA. Glucocorticoids and renal Na+ transport: implications for hypertension and salt sensitivity. J Physiol 2014; 592:1731-44. [PMID: 24535442 PMCID: PMC4001748 DOI: 10.1113/jphysiol.2013.267609] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The clinical manifestations of glucocorticoid excess include central obesity, hyperglycaemia, dyslipidaemia, electrolyte abnormalities and hypertension. A century on from Cushing's original case study, these cardinal features are prevalent in industrialized nations. Hypertension is the major modifiable risk factor for cardiovascular and renal disease and reflects underlying abnormalities of Na+ homeostasis. Aldosterone is a master regulator of renal Na+ transport but here we argue that glucocorticoids are also influential, particularly during moderate excess. The hypothalamic–pituitary–adrenal axis can affect renal Na+ homeostasis on multiple levels, systemically by increasing mineralocorticoid synthesis and locally by actions on both the mineralocorticoid and glucocorticoid receptors, both of which are expressed in the kidney. The kidney also expresses both of the 11β-hydroxysteroid dehydrogenase (11βHSD) enzymes. The intrarenal generation of active glucocorticoid by 11βHSD1 stimulates Na+ reabsorption; failure to downregulate the enzyme during adaption to high dietary salt causes salt-sensitive hypertension. The deactivation of glucocorticoid by 11βHSD2 underpins the regulatory dominance for Na+ transport of mineralocorticoids and defines the ‘aldosterone-sensitive distal nephron’. In summary, glucocorticoids can stimulate renal transport processes conventionally attributed to the renin–angiotensin–aldosterone system. Importantly, Na+ and volume homeostasis do not exert negative feedback on the hypothalamic–pituitary–adrenal axis. These actions are therefore clinically relevant and may contribute to the pathogenesis of hypertension in conditions associated with elevated glucocorticoid levels, such as the metabolic syndrome and chronic stress.
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Affiliation(s)
- Robert W Hunter
- University/BHF Centre for Cardiovascular Science, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, UK.
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21
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Hunter RW, Craigie E, Homer NZM, Mullins JJ, Bailey MA. Acute inhibition of NCC does not activate distal electrogenic Na+ reabsorption or kaliuresis. Am J Physiol Renal Physiol 2014; 306:F457-67. [PMID: 24402096 PMCID: PMC3920023 DOI: 10.1152/ajprenal.00339.2013] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Na(+) reabsorption from the distal renal tubule involves electroneutral and electrogenic pathways, with the latter promoting K(+) excretion. The relative activities of these two pathways are tightly controlled, participating in the minute-to-minute regulation of systemic K(+) balance. The pathways are interdependent: the activity of the NaCl cotransporter (NCC) in the distal convoluted tubule influences the activity of the epithelial Na(+) channel (ENaC) downstream. This effect might be mediated by changes in distal Na(+) delivery per se or by molecular and structural adaptations in the connecting tubule and collecting ducts. We hypothesized that acute inhibition of NCC activity would cause an immediate increase in Na(+) flux through ENaC, with a concomitant increase in renal K(+) excretion. We tested this using renal clearance methodology in anesthetized mice, by the administration of hydrochlorothiazide (HCTZ) and/or benzamil (BZM) to exert specific blockade of NCC and ENaC, respectively. Bolus HCTZ elicited a natriuresis that was sustained for up to 110 min; urinary K(+) excretion was not affected. Furthermore, the magnitude of the natriuresis was no greater during concomitant BZM administration. This suggests that ENaC-mediated Na(+) reabsorption was not normally limited by Na(+) delivery, accounting for the absence of thiazide-induced kaliuresis. After dietary Na(+) restriction, HCTZ elicited a kaliuresis, but the natiuretic effect of HCTZ was not enhanced by BZM. Our findings support a model in which inhibition of NCC activity does not increase Na(+) reabsorption through ENaC solely by increasing distal Na(+) delivery but rather by inducing a molecular and structural adaptation in downstream nephron segments.
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Affiliation(s)
- Robert W Hunter
- Univ. of Edinburgh/BHF Centre for Cardiovascular Science, Rm. W3.33B, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, UK.
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22
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Rossier BC, Staub O, Hummler E. Genetic dissection of sodium and potassium transport along the aldosterone-sensitive distal nephron: importance in the control of blood pressure and hypertension. FEBS Lett 2013; 587:1929-41. [PMID: 23684652 DOI: 10.1016/j.febslet.2013.05.013] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2013] [Accepted: 05/06/2013] [Indexed: 10/26/2022]
Abstract
In this review, we discuss genetic evidence supporting Guyton's hypothesis stating that blood pressure control is critically depending on fluid handling by the kidney. The review is focused on the genetic dissection of sodium and potassium transport in the distal nephron and the collecting duct that are the most important sites for the control of sodium and potassium balance by aldosterone and angiotensin II. Thanks to the study of Mendelian forms of hypertension and their corresponding transgenic mouse models, three main classes of diuretic receptors (furosemide, thiazide, amiloride) and the main components of the aldosterone- and angiotensin-dependent signaling pathways were molecularly identified over the past 20 years. This will allow to design rational strategies for the treatment of hypertension and for the development of the next generation of diuretics.
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23
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Lauterburg M, Escher G, Dick B, Ackermann D, Frey FJ. Uninephrectomy reduces 11β-hydroxysteroid dehydrogenase type 1 and type 2 concomitantly with an increase in blood pressure in rats. J Endocrinol 2012; 214:373-80. [PMID: 22739210 DOI: 10.1530/joe-12-0200] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Renal allograft donors are at risk of developing hypertension. Here, we hypothesized that this risk is at least in part explained by an enhanced intracellular availability of 11β-hydroxyglucocorticoids due to an increased 11β-hydroxysteroid dehydrogenase type 1 enzyme (11β-HSD1), an intracellular prereceptor activator of biologically inactive 11-ketocorticosteroids in the liver, and/or a diminished 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2), an inactivator of 11β-hydroxyglucocorticoids in the kidney. To test this hypothesis, uninephrectomized (UNX) (n=9) and sham-operated (n=10) adult Sprague-Dawley rats were investigated. Mean arterial blood pressure and heart rate were measured continuously by telemetry for 6 days in week 5 after UNX. The mRNA of 11β-Hsd1 and 11β-Hsd2 in liver and kidney tissues were assessed by RT-PCR and the 11β-HSD activities were directly quantified in their corresponding tissues by determining the ratios of (tetrahydrocorticosterone+5α-tetrahydrocorticosterone)/tetrahydrodehydrocorticosterone ((THB+5α-THB)/THA) and of corticosterone/dehydrocorticosterone (B/A) by gas chromatography-mass spectrometry. The apparent total body activities of 11β-HSD1 and 11β-HSD2 were estimated using the urinary and plasma ratios of (THB+5α-THB)/THA and B/A. Mean arterial blood pressure was increased after UNX when compared with sham operation. Hepatic mRNA content of 11β-Hsd1 and hepatic, plasma, and urinary ratios of (THB+5α-THB)/THA were decreased after UNX, indicating diminished access of glucocorticoids to its receptors. In renal tissue, 11β-Hsd2 mRNA was reduced and B/A ratios measured in kidney, plasma, and urine were increased, indicating reduced 11β-HSD2 activity and enhanced access of glucocorticoids to mineralocorticoid receptors. Both 11β-HSD1 and 11β-HSD2 are downregulated after UNX in rats, a constellation considered to induce hypertension.
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Affiliation(s)
- M Lauterburg
- Department of Nephrology and Hypertension, University Hospital Bern, Inselspital, Freiburgstrasse 15, 3010 Bern, Switzerland
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24
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Fenton RA. Another conundrum to concentrate on? Am J Physiol Renal Physiol 2012; 303:F492-3. [DOI: 10.1152/ajprenal.00328.2012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Robert A. Fenton
- Department of Biomedicine and Center for Interactions of Proteins in Epithelial Transport (InterPrET), Aarhus University, Aarhus, Denmark
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25
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Craigie E, Evans LC, Mullins JJ, Bailey MA. Failure to downregulate the epithelial sodium channel causes salt sensitivity in Hsd11b2 heterozygote mice. Hypertension 2012; 60:684-90. [PMID: 22777941 DOI: 10.1161/hypertensionaha.112.196410] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In vivo, the enzyme 11β-hydroxysteroid dehydrogenase type 2 influences ligand access to the mineralocorticoid receptor. Ablation of the encoding gene, HSD11B2, causes the hypertensive syndrome of apparent mineralocorticoid excess. Studies in humans and experimental animals have linked reduced 11β-hydroxysteroid dehydrogenase type 2 activity and salt sensitivity of blood pressure. In the present study, renal mechanisms underpinning salt sensitivity were investigated in Hsd11b2(+/-) mice fed low-, standard-, and high-sodium diets. In wild-type mice, there was a strong correlation between dietary sodium content and fractional sodium excretion but not blood pressure. High sodium feeding abolished amiloride-sensitive sodium reabsorption, consistent with downregulation of the epithelial sodium channel. In Hsd11b2(+/-) mice, the natriuretic response to increased dietary sodium content was blunted, and epithelial sodium channel activity persisted. High-sodium diet also reduced renal blood flow and increased blood pressure in Hsd11b2(+/-) mice. Aldosterone was modulated by dietary sodium in both genotypes, and salt sensitivity in Hsd11b2(+/-) mice was associated with increased plasma corticosterone levels. Chronic administration of an epithelial sodium channel blocker or a glucocorticoid receptor antagonist prevented salt sensitivity in Hsd11b2(+/-) mice, whereas mineralocorticoid receptor blockade with spironolactone did not. This study shows that reduced 11β-hydroxysteroid dehydrogenase type 2 causes salt sensitivity of blood pressure because of impaired renal natriuretic capacity. This reflects deregulation of epithelial sodium channels and increased renal vascular resistance. The phenotype is not caused by illicit activation of mineralocorticoid receptors by glucocorticoids but by direct activation of glucocorticoid receptors.
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Affiliation(s)
- Eilidh Craigie
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
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26
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Evans LC, Livingstone DE, Kenyon CJ, Jansen MA, Dear JW, Mullins JJ, Bailey MA. A urine-concentrating defect in 11β-hydroxysteroid dehydrogenase type 2 null mice. Am J Physiol Renal Physiol 2012; 303:F494-502. [PMID: 22622456 DOI: 10.1152/ajprenal.00165.2012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
In aldosterone target tissues, 11β-hydroxysteroid dehydrogenase type 2 (11βHSD2) is coexpressed with mineralocorticoid receptors (MR) and protects the receptor from activation by glucocorticoids. Null mutations in the encoding gene, HSD11B2, cause apparent mineralocorticoid excess, in which hypertension is thought to reflect volume expansion secondary to sodium retention. Hsd11b2(-/-) mice are indeed hypertensive, but impaired natriuretic capacity is associated with significant volume contraction, suggestive of a urine concentrating defect. Water turnover and the urine concentrating response to a 24-h water deprivation challenge were therefore assessed in Hsd11b2(-/-) mice and controls. Hsd11b2(-/-) mice have a severe and progressive polyuric/polydipsic phenotype. In younger mice (∼2 mo of age), polyuria was associated with decreased abundance of aqp2 and aqp3 mRNA. The expression of other genes involved in water transport (aqp4, slc14a2, and slc12a2) was not changed. The kidney was structurally normal, and the concentrating response to water deprivation was intact. In older Hsd11b2(-/-) mice (>6 mo), polyuria was associated with a severe atrophy of the renal medulla and downregulation of aqp2, aqp3, aqp4, slc14a2, and slc12a2. The concentrating response to water deprivation was impaired, and the natriuretic effect of the loop diuretic bumetanide was lost. In older Hsd11b2(-/-) mice, the V2 receptor agonist desmopressin did not restore full urine concentrating capacity. We find that Hsd11b2(-/-) mice develop nephrogenic diabetes insipidus. Gross changes to renal structure are observed, but these were probably secondary to sustained polyuria, rather than of developmental origin.
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Affiliation(s)
- Louise C Evans
- BHF Centre for Cardiovascular Science, The Queen's Medical Research Institute, The Univ. of Edinburgh, 47, Little France Crescent, Edinburgh, UK EH16 4TJ
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Zubcevic J, Waki H, Raizada MK, Paton JFR. Autonomic-immune-vascular interaction: an emerging concept for neurogenic hypertension. Hypertension 2011; 57:1026-33. [PMID: 21536990 DOI: 10.1161/hypertensionaha.111.169748] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Jasenka Zubcevic
- Department of Physiology and Functional Genomics, McKnight Brain Institute, 1600 SW Archer Rd, Gainesville, FL 32610, USA
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28
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Kratschmar DV, Vuorinen A, Da Cunha T, Wolber G, Classen-Houben D, Doblhoff O, Schuster D, Odermatt A. Characterization of activity and binding mode of glycyrrhetinic acid derivatives inhibiting 11β-hydroxysteroid dehydrogenase type 2. J Steroid Biochem Mol Biol 2011; 125:129-42. [PMID: 21236343 DOI: 10.1016/j.jsbmb.2010.12.019] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2010] [Revised: 12/24/2010] [Accepted: 12/31/2010] [Indexed: 12/21/2022]
Abstract
Modulation of intracellular glucocorticoid availability is considered as a promising strategy to treat glucocorticoid-dependent diseases. 18β-Glycyrrhetinic acid (GA), the biologically active triterpenoid metabolite of glycyrrhizin, which is contained in the roots and rhizomes of licorice (Glycyrrhiza spp.), represents a well-known but non-selective inhibitor of 11β-hydroxysteroid dehydrogenases (11β-HSDs). However, to assess the physiological functions of the respective enzymes and for potential therapeutic applications selective inhibitors are needed. In the present study, we applied bioassays and 3D-structure modeling to characterize nine 11β-HSD1 and fifteen 11β-HSD2 inhibiting GA derivatives. Comparison of the GA derivatives in assays using cell lysates revealed that modifications at the 3-hydroxyl and/or the carboxyl led to highly selective and potent 11β-HSD2 inhibitors. The data generated significantly extends our knowledge on structure-activity relationship of GA derivatives as 11β-HSD inhibitors. Using recombinant enzymes we found also potent inhibition of mouse 11β-HSD2, despite significant species-specific differences. The selected GA derivatives potently inhibited 11β-HSD2 in intact SW-620 colon cancer cells, although the rank order of inhibitory potential differed from that obtained in cell lysates. The biological activity of compounds was further demonstrated in glucocorticoid receptor (GR) transactivation assays in cells coexpressing GR and 11β-HSD1 or 11β-HSD2. 3D-structure modeling provides an explanation for the differences in the selectivity and activity of the GA derivatives investigated. The most potent and selective 11β-HSD2 inhibitors should prove useful as mechanistic tools for further anti-inflammatory and anti-cancer in vitro and in vivo studies. Article from the Special issue on Targeted Inhibitors.
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Affiliation(s)
- Denise V Kratschmar
- Swiss Center for Applied Human Toxicology and Division of Molecular and Systems Toxicology, Department of Pharmaceutical Sciences, University of Basel, Klingelbergstrasse 50, CH-4056 Basel, Switzerland
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29
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Bailey MA, Craigie E, Livingstone DEW, Kotelevtsev YV, Al-Dujaili EAS, Kenyon CJ, Mullins JJ. Hsd11b2 haploinsufficiency in mice causes salt sensitivity of blood pressure. Hypertension 2011; 57:515-520. [PMID: 21282561 DOI: 10.1161/hypertensionaha.110.163782] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Salt sensitivity of blood pressure is an independent risk factor for cardiovascular morbidity. Mechanistically, abnormal mineralocorticoid action and subclinical renal impairment may blunt the natriuretic response to high sodium intake, causing blood pressure to rise. 11β-Hydroxysteroid dehydrogenase type 2 (11βHSD2) controls ligand access to the mineralocorticoid receptor, and ablation of the enzyme causes severe hypertension. Polymorphisms in HSD11B2 are associated with salt sensitivity of blood pressure in normotensives. In this study, we used mice heterozygote for a null mutation in Hsd11b2 (Hsd11b2(+/-)) to define the mechanisms linking reduced enzyme activity to salt sensitivity of blood pressure. A high-sodium diet caused a rapid and sustained increase in blood pressure in Hsd11b2(+/-) mice but not in wild-type littermates. During the adaptation to high-sodium diet, heterozygotes displayed impaired sodium excretion, a transient positive sodium balance, and hypokalemia. After 21 days of high-sodium feeding, Hsd11b2(+/-) mice had an increased heart weight. Mineralocorticoid receptor antagonism partially prevented the increase in heart weight but not the increase in blood pressure. Glucocorticoid receptor antagonism prevented the rise in blood pressure. In Hsd11b2(+/-) mice, high-sodium feeding caused suppression of aldosterone and a moderate but sustained increase in corticosterone. This study demonstrates an inverse relationship among 11βHSD2 activity, heart weight, and blood pressure in a clinically important context. Reduced activity causes salt sensitivity of blood pressure, but this does not reflect illicit activation of mineralocorticoid receptors by glucocorticoids. Instead, we have identified a novel interaction among 11βHSD2, dietary salt, and circulating glucocorticoids.
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Affiliation(s)
- Matthew A Bailey
- British Heart Foundation/University Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, Scotland, UK
| | - Eilidh Craigie
- British Heart Foundation/University Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, Scotland, UK
| | - Dawn E W Livingstone
- British Heart Foundation/University Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, Scotland, UK
| | - Yuri V Kotelevtsev
- British Heart Foundation/University Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, Scotland, UK.,Stem Cell Genome Modification Laboratory, Puschino State University, Russia
| | - Emad A S Al-Dujaili
- Dietetics, Nutrition and Biological Sciences Research, Queen Margaret University, Edinburgh, Scotland, UK
| | - Christopher J Kenyon
- British Heart Foundation/University Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, Scotland, UK
| | - John J Mullins
- British Heart Foundation/University Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, Scotland, UK
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30
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Deuchar GA, McLean D, Hadoke PWF, Brownstein DG, Webb DJ, Mullins JJ, Chapman K, Seckl JR, Kotelevtsev YV. 11β-hydroxysteroid dehydrogenase type 2 deficiency accelerates atherogenesis and causes proinflammatory changes in the endothelium in apoe-/- mice. Endocrinology 2011; 152:236-246. [PMID: 21106873 PMCID: PMC3977042 DOI: 10.1210/en.2010-0925] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Mineralocorticoid receptor (MR) activation is proinflammatory and proatherogenic. Antagonism of MR improves survival in humans with congestive heart failure caused by atherosclerotic disease. In animal models, activation of MR exacerbates atherosclerosis. The enzyme 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) prevents inappropriate activation of the MR by inactivating glucocorticoids in mineralocorticoid-target tissues. To determine whether glucocorticoid-mediated activation of MR increases atheromatous plaque formation, we generated Apoe(-/-)/11β-HSD2(-/-) double-knockout (E/b2) mice. On chow diet, E/b2 mice developed atherosclerotic lesions by 3 months of age, whereas Apolipoprotein E (Apoe(-/-)) mice remained lesion free. Brachiocephalic plaques in 3-month-old E/b2 mice showed increased macrophage and lipid content and reduced collagen content compared with similar sized brachiocephalic plaques in 6-month-old Apoe(-/-) mice. Crucially, treatment of E/b2 mice with eplerenone, an MR antagonist, reduced plaque development and macrophage infiltration while increasing collagen and smooth muscle cell content without any effect on systolic blood pressure. In contrast, reduction of systolic blood pressure in E/b2 mice using the epithelial sodium channel blocker amiloride produced a less-profound atheroprotective effect. Vascular cell adhesion molecule 1 expression was increased in the endothelium of E/b2 mice compared with Apoe(-/-) mice. Similarly, aldosterone increased vascular cell adhesion molecule 1 expression in mouse aortic endothelial cells, an effect mimicked by corticosterone only in the presence of an 11β-HSD2 inhibitor. Thus, loss of 11β-HSD2 leads to striking atherogenesis associated with activation of MR, stimulating proinflammatory processes in the endothelium of E/b2 mice.
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Affiliation(s)
- Graeme A Deuchar
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, College of Medicine and Veterinary Medicine, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - Danielle McLean
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, College of Medicine and Veterinary Medicine, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - Patrick W F Hadoke
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, College of Medicine and Veterinary Medicine, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - David G Brownstein
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, College of Medicine and Veterinary Medicine, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - David J Webb
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, College of Medicine and Veterinary Medicine, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - John J Mullins
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, College of Medicine and Veterinary Medicine, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - Karen Chapman
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, College of Medicine and Veterinary Medicine, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - Jonathan R Seckl
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, College of Medicine and Veterinary Medicine, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - Yuri V Kotelevtsev
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, College of Medicine and Veterinary Medicine, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
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31
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Sapoval M, Tamari I, Goffette P, Downes M, Senechal Q, Fanelli F, Reimer P, Negaiwi Z, De Cassin P, Heye S, Korobov V, Tsetis D, Abada H. One year clinical outcomes of renal artery stenting: the results of ODORI Registry. Cardiovasc Intervent Radiol 2010; 33:475-83. [PMID: 19908091 PMCID: PMC2868171 DOI: 10.1007/s00270-009-9733-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2009] [Accepted: 09/23/2009] [Indexed: 11/08/2022]
Abstract
The safety, efficacy and long term clinical benefits of renal artery revascularization by stenting are still a matter of debate. The aim of our study was to define the safety and efficacy of renal artery stenting with the Tsunami peripheral stent (Terumo Corporation, Tokyo, Japan). The ODORI was a prospective, multicentre registry which enrolled 251 consecutive patients, (276 renal arteries) in 36 centres across Europe. The primary endpoint was acute procedural success defined as <30% residual stenosis after stent placement. Secondary endpoints included major adverse events, blood pressure control, serum creatinine level, and target lesion revascularization (TLR) at 6 and 12 months. Patients were 70 +/- 10 years old, 59% were male, 33% had diabetes, and 96% hypertension. The main indications for renal stent implantation were hypertension in 83% and renal salvage in 39%. Direct stent implantation was performed in 76% of the cases. Acute success rate was 100% with residual stenosis of 2.5 +/- 5.4%. Systolic/diastolic blood pressure decreased from a mean of 171/89 at baseline to 142/78 mmHg at 6 months (p < 0.0001 vs. baseline), and 141/80 mmHg at 12 months (p < 0.0001 vs. baseline). Mean serum creatinine concentration did not change significantly in the total population. However, there was significant improvement in the highest tercile (from 283 micromol/l at baseline to 205 and 209 micromol/l at 6 and 12 months respectively). At 12-months, rates of restenosis and TLR were 6.6 and 0.8% respectively. The 12 month cumulative rate of all major clinical adverse events was 6.4% while the rate of device or procedure related events was 2.4%. In hypertensive patients with atherosclerotic renal artery stenosis Tsunami peripheral balloon-expandable stent provides a safe revascularization strategy, with a potential beneficial impact on hypertension control and renal function in the highest risk patients.
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Affiliation(s)
- M Sapoval
- Hôpital Européen Georges Pompidou, Cardiovascular Radiology, 20 rue Leblanc, 75015 Paris, France.
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Van Agtmael T, Bailey MA, Schlötzer-Schrehardt U, Craigie E, Jackson IJ, Brownstein DG, Megson IL, Mullins JJ. Col4a1 mutation in mice causes defects in vascular function and low blood pressure associated with reduced red blood cell volume. Hum Mol Genet 2010; 19:1119-28. [PMID: 20056676 PMCID: PMC3199583 DOI: 10.1093/hmg/ddp584] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Collagen type IV is the major structural component of the basement membrane and COL4A1 mutations cause adult small vessel disease, familial porencephaly and hereditary angiopathy with nephropathy aneurysm and cramps (HANAC) syndrome. Here, we show that animals with a Col4a1 missense mutation (Col4a1(+/Raw)) display focal detachment of the endothelium from the media and age-dependent defects in vascular function including a reduced response to nor-epinephrine. Age-dependent hypersensitivity to acetylcholine is abolished by inhibition of nitric oxide synthase (NOS) activity, indicating that Col4a1 mutations affect vasorelaxation mediated by endothelium-derived nitric oxide (NO). These defects are associated with a reduction in basal NOS activity and the development of heightened NO sensitivity of the smooth muscle. The vascular function defects are physiologically relevant as they maintain in part the hypotension in mutant animals, which is primarily associated with a reduced red blood cell volume due to a reduction in red blood cell number, rather than defects in kidney function. To understand the molecular mechanism underlying these vascular defects, we examined the deposition of collagen type IV in the basement membrane, and found it to be defective. Interestingly, this mutation also leads to activation of the unfolded protein response. In summary, our results indicate that mutations in COL4A1 result in a complex vascular phenotype encompassing defects in maintenance of vascular tone, endothelial cell function and blood pressure regulation.
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MESH Headings
- Animals
- Animals, Newborn
- Blood Vessels/enzymology
- Blood Vessels/pathology
- Blood Vessels/physiopathology
- Blood Vessels/ultrastructure
- Cerebral Hemorrhage/blood
- Cerebral Hemorrhage/complications
- Cerebral Hemorrhage/pathology
- Cerebral Hemorrhage/physiopathology
- Collagen Type IV/genetics
- Cyclic GMP/pharmacology
- Endothelial Cells/drug effects
- Endothelial Cells/enzymology
- Endothelial Cells/pathology
- Erythrocyte Volume/physiology
- Homeostasis/drug effects
- Hypotension/blood
- Hypotension/complications
- Hypotension/physiopathology
- Mice
- Mice, Inbred C57BL
- Mice, Mutant Strains
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/pathology
- Muscle, Smooth, Vascular/physiopathology
- Muscle, Smooth, Vascular/ultrastructure
- Mutation/genetics
- Nitric Oxide/pharmacology
- Nitric Oxide Synthase/metabolism
- Unfolded Protein Response/drug effects
- Vasodilation/drug effects
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Affiliation(s)
- Tom Van Agtmael
- Faculty of Biomedical and Life Sciences, University of Glasgow, University Avenue, Glasgow G12 8QQ, UK.
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Cooper MS, Stewart PM. 11Beta-hydroxysteroid dehydrogenase type 1 and its role in the hypothalamus-pituitary-adrenal axis, metabolic syndrome, and inflammation. J Clin Endocrinol Metab 2009; 94:4645-54. [PMID: 19837912 DOI: 10.1210/jc.2009-1412] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
CONTEXT 11Beta-hydroxysteroid dehydrogenase (11beta-HSD) enzymes are now appreciated to be important regulators of hormone action at a tissue level. 11Beta-HSD1 is widely expressed and increases glucocorticoid action through its unique ability to convert inactive glucocorticoids (cortisone in man, 11-dehydrocorticosterone in rodents) to their active forms (cortisol and corticosterone, respectively). The enzyme has roles in the normal hypothalamus-pituitary-adrenal (HPA) axis, has been implicated in metabolic syndrome, and may modulate various aspects of the immune response. EVIDENCE ACQUISITION A review of published, peer-reviewed medical literature (1990 to June 2009) on the physiology and pathophysiology of 11beta-HSD1 was performed with an emphasis on HPA axis consequences, the metabolic syndrome, and the inflammatory response. EVIDENCE SYNTHESIS Studies of patients with genetic defects in 11beta-HSD1 action show abnormal HPA axis responses with hyperandrogenism being a major consequence. The mechanisms underlying these abnormalities have been explored in mouse models with targeted deletion of components of the 11beta-HSD1 system. A range of experimental studies emphasize the role of 11beta-HSD1 in the metabolic syndrome and the potential for treatment with chemical inhibitors. An emerging area is the role of 11beta-HSD1 in the inflammatory response. CONCLUSIONS 11Beta-HSD1 activity is an important component of the HPA axis and contributes to the metabolic syndrome and the normal immune response. Ongoing clinical observations and the development of selective inhibitors will further clarify the role of 11beta-HSD1 in these areas.
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Affiliation(s)
- Mark S Cooper
- Centre for Endocrinology, Diabetes, and Metabolism, School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, United Kingdom B15 2TT
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Dunbar DR, Khaled H, Evans LC, Al-Dujaili EAS, Mullins LJ, Mullins JJ, Kenyon CJ, Bailey MA. Transcriptional and physiological responses to chronic ACTH treatment by the mouse kidney. Physiol Genomics 2009; 40:158-66. [PMID: 19920212 PMCID: PMC2825763 DOI: 10.1152/physiolgenomics.00088.2009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
We investigated the effects on urinary steroid and electrolyte excretion and renal gene expression of chronic infusions of ACTH in the mouse. ACTH caused a sustained increase in corticosteroid excretion; aldosterone excretion was only transiently elevated. There was an increase in the excretion of deoxycorticosterone, a weak mineralocorticoid, to levels of physiological significance. Nevertheless, we observed neither antinatriuresis nor kaliuresis in ACTH-treated mice, and plasma renin activity was not suppressed. We identified no changes in expression of mineralocorticoid target genes. Water turnover was increased in chronic ACTH-treated mice, as were hematocrit and hypertonicity: volume contraction is consistent with high levels of glucocorticoid. ACTH-treated mice exhibited other signs of glucocorticoid excess, such as enhanced weight gain and involution of the thymus. We identified novel ACTH-induced changes in 1) genes involved in vitamin D (Cyp27b1, Cyp24a1, Gc) and calcium (Sgk, Calb1, Trpv5) metabolism associated with calciuria and phosphaturia; 2) genes that would be predicted to desensitize the kidney to glucocorticoid action (Nr3c1, Hsd11b1, Fkbp5); and 3) genes encoding transporters of enzyme systems associated with xenobiotic metabolism and oxidative stress. Although there is evidence that ACTH-induced hypertension is a function of physiological cross talk between glucocorticoids and mineralocorticoids, the present study suggests that the major changes in electrolyte and fluid homeostasis and renal function are attributable to glucocorticoids. The calcium and organic anion metabolism pathways that are affected by ACTH may explain some of the known adverse effects associated with glucocorticoid excess.
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Affiliation(s)
- Donald R Dunbar
- Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, United Kingdom.
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Bailey MA, Mullins JJ, Kenyon CJ. Mineralocorticoid and Glucocorticoid Receptors Stimulate Epithelial Sodium Channel Activity in a Mouse Model of Cushing Syndrome. Hypertension 2009; 54:890-6. [DOI: 10.1161/hypertensionaha.109.134973] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Experiments in Cushing patients and healthy control subjects receiving adrenocorticotropic hormone (ACTH) indicate that transient renal sodium retention may contribute to the generation of hypertension. Here we have investigated the effect of chronic ACTH infusion on renal sodium handling in adult male C57BL/6J mice using selective antagonists to dissect mineralocorticoid and glucocorticoid receptor–mediated pathways. Mice were infused via osmotic minipump with ACTH (2.5 μg/d) or saline for 2 weeks before being anesthetized for renal function experiments. ACTH caused an increase in blood pressure and a reduction in fractional sodium excretion associated with enhanced activity of the epithelial sodium channel. Given separately, spironolactone and RU38486 blunted the pressor response to ACTH and the increased epithelial sodium channel activity; combined mineralocorticoid and glucocorticoid receptor blockade was required to resolve the response to ACTH excess. Dietary sodium depletion also prevented ACTH-induced hypertension. The effect of increased sodium reabsorption in the distal nephron is offset by downregulation of Na-K-Cl cotransport in the loop of Henle. Sodium excretion is normalized chronically, but blood pressure remains high; acute blockade of V1 receptors and α1 adrenoceptors in combination restored blood pressure to control values. In summary, ACTH excess promotes renal sodium reabsorption, contributing to the increased blood pressure; both glucocorticoid and mineralocorticoid receptor pathways are involved. These data are relevant to conditions associated with overactivity of the hypothalamic-pituitary-adrenal axis, such as obesity and chronic stress.
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Affiliation(s)
- Matthew A. Bailey
- From the Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - John J. Mullins
- From the Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Christopher J. Kenyon
- From the Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
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Walker DJ, Elliott J, Syme HM. Urinary cortisol/cortisone ratios in hypertensive and normotensive cats. J Feline Med Surg 2009; 11:442-8. [DOI: 10.1016/j.jfms.2008.10.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/08/2008] [Indexed: 10/21/2022]
Abstract
Hypertension is a common problem in older cats, particularly associated with chronic kidney disease (CKD). Reduced activity of 11β-hydroxysteroid dehydrogenase type 2 predisposes to hypertension in human patients by allowing excessive stimulation of the mineralocorticoid receptor by cortisol. This study was designed to test the hypothesis that reduced conversion of cortisol to cortisone contributes to the development of systemic hypertension in some cats with CKD and idiopathic hypertension (iHT). The study included 60 client-owned cats: 21 clinically normal, 16 normotensive cats with CKD (NTCKD), 14 hypertensive cats with CKD (HTCKD) and nine iHTs. Urine cortisol and cortisone were extracted into dichloromethane and chloroform, respectively, prior to analysis by radioimmunoassay. Data are reported as median and range. The Kruskall–Wallis test was used to compare cortisol:cortisone ratios between groups with post-hoc testing using the Mann–Whitney U test. Wilcoxon signed-ranks test was used to compare results before and after treatment of hypertensive cats with amlodipine. The urinary cortisol:cortisone ratio was significantly higher in clinically normal cats (0.87; 0.46–1.39) when compared to NTCKD (0.60; 0.35–1.20; P<0.001), HTCKD (0.62; 0.34–1.00; P=0.002) and cats with iHT (0.65; 0.46–0.85; P=0.015). No statistical difference was detected between NTCKD, HTCKD and iHT groups. No effect of anti-hypertensive treatment on the urinary cortisol–cortisone ratio was detected ( P=0.327). Reduced urinary cortisol to cortisone conversion does not appear to be associated with systemic hypertension in cats. In fact, the cortisol to cortisone shuttle appears to be more effective in cats with CKD (hypertensive and normotensive) and iHT than clinically normal cats. The mechanism for this potentially adaptive response to kidney disease is not clear.
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Affiliation(s)
- David J. Walker
- Department of Veterinary Clinical Sciences, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Herts AL9 7TA, UK
| | - Jonathan Elliott
- Department of Veterinary Basic Sciences, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Herts AL9 7TA, UK
| | - Harriet M. Syme
- Department of Veterinary Clinical Sciences, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Herts AL9 7TA, UK
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Abstract
Pharmacological and physiological phenomena suggest that cells somewhere inside the central nervous system are responsive to aldosterone. Here, we present the fundamental physiological limitations for aldosterone action in the brain, including its limited blood-brain barrier penetration and its substantial competition from glucocorticoids. Recently, a small group of neurons with unusual sensitivity to circulating aldosterone were identified in the nucleus of the solitary tract. We review the discovery and characterization of these neurons, which express the enzyme 11beta-hydroxysteroid dehydrogenase type 2, and consider alternative proposals regarding sites and mechanisms for mineralocorticoid action within the brain.
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Affiliation(s)
- Joel C Geerling
- Dept. of Anatomy and Neurobiology-Box 8108, Washington Univ. School of Medicine, 660 S. Euclid Ave., St. Louis, MO 63110, USA.
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Odermatt A, Gumy C. Glucocorticoid and mineralocorticoid action: Why should we consider influences by environmental chemicals? Biochem Pharmacol 2008; 76:1184-93. [DOI: 10.1016/j.bcp.2008.07.019] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2008] [Revised: 07/15/2008] [Accepted: 07/15/2008] [Indexed: 11/25/2022]
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