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Xu C. Extra-adrenal aldosterone: a mini review focusing on the physiology and pathophysiology of intrarenal aldosterone. Endocrine 2024; 83:285-301. [PMID: 37847370 DOI: 10.1007/s12020-023-03566-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 10/08/2023] [Indexed: 10/18/2023]
Abstract
PURPOSE Accumulating evidence has demonstrated the existence of extra-adrenal aldosterone in various tissues, including the brain, heart, vascular, adipocyte, and kidney, mainly based on the detection of the CYP11B2 (aldosterone synthase, cytochrome P450, family 11, subfamily B, polypeptide 2) expression using semi-quantitative methods including reverse transcription-polymerase chain reaction and antibody-based western blotting, as well as local tissue aldosterone levels by antibody-based immunosorbent assays. This mini-review highlights the current evidence and challenges in extra-adrenal aldosterone, focusing on intrarenal aldosterone. METHODS A narrative review. RESULTS Locally synthesized aldosterone may play a vital role in various physio-pathological processes, especially cardiovascular events. The site of local aldosterone synthesis in the kidney may include the mesangial cells, podocytes, proximal tubules, and collecting ducts. The synthesis of renal aldosterone may be regulated by (pro)renin receptor/(pro)renin, angiotensin II/Angiotensin II type 1 receptor, wnt/β-catenin, cyclooxygenase-2/prostaglandin E2, and klotho. Enhanced renal aldosterone release promotes Na+ reabsorption and K+ excretion in the distal nephron and may contribute to the progress of diabetic nephropathy and salt-related hypertension. CONCLUSIONS Inhibition of intrarenal aldosterone signaling by aldosterone synthase inhibitors or mineralocorticoid receptor antagonists may be a hopeful pharmacological technique for the therapy of diabetic nephropathy and saltrelated hypertension. Yet, current reports are often conflicting or ambiguous, leading many to question whether extra-adrenal aldosterone exists, or whether it is of any physiological and pathophysiological significance.
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Affiliation(s)
- Chuanming Xu
- Translational Medicine Centre, Jiangxi University of Chinese Medicine, Nanchang, 330002, Jiangxi, China.
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Chen L, Adolf C, Reincke M, Schneider H. Salt and Aldosterone - Reciprocal and Combined Effects in Preclinical Models and Humans. Horm Metab Res 2024; 56:99-106. [PMID: 37683690 PMCID: PMC10781566 DOI: 10.1055/a-2172-7228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 09/03/2023] [Indexed: 09/10/2023]
Abstract
Primary aldosteronism is an endocrine disorder caused by excessive production of aldosterone by the adrenal glands, and is recognized as the most important cause of endocrine hypertension. With specific therapy, this type of hypertension is potentially curable. In the general population, high salt intake increases the risk for cardiovascular diseases like stroke. In populations with aldosterone excess, observational and experimental data suggest that aldosterone-induced organ damage requires a combination of high dietary salt intake and high plasma aldosterone, i.e., plasma aldosterone levels inappropriately high for salt status. Therefore, understanding the relationship between plasma aldosterone levels and dietary salt intake and the nature of their combined effects is crucial for developing effective prevention and treatment strategies. In this review, we present an update on findings about primary aldosteronism and salt intake and the underlying mechanisms governing their interaction.
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Affiliation(s)
- Li Chen
- Medizinische Klinik und Poliklinik IV, LMU Klinikum, LMU
München, München, Germany
| | - Christian Adolf
- Medizinische Klinik und Poliklinik IV, LMU Klinikum, LMU
München, München, Germany
| | - Martin Reincke
- Medizinische Klinik und Poliklinik IV, LMU Klinikum, LMU
München, München, Germany
| | - Holger Schneider
- Medizinische Klinik und Poliklinik IV, LMU Klinikum, LMU
München, München, Germany
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Michel JB, Lagrange J, Regnault V, Lacolley P. Conductance Artery Wall Layers and Their Respective Roles in the Clearance Functions. Arterioscler Thromb Vasc Biol 2022; 42:e253-e272. [PMID: 35924557 DOI: 10.1161/atvbaha.122.317759] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Evolutionary organization of the arterial wall into layers occurred concomitantly with the emergence of a highly muscularized, pressurized arterial system that facilitates outward hydraulic conductance and mass transport of soluble substances across the arterial wall. Although colliding circulating cells disperse potential energy within the arterial wall, the different layers counteract this effect: (1) the endothelium ensures a partial barrier function; (2) the media comprises smooth muscle cells capable of endocytosis/phagocytosis; (3) the outer adventitia and perivascular adipocytic tissue are the final receptacles of convected substances. While the endothelium forms a physical and a biochemical barrier, the medial layer is avascular, relying on the specific permeability properties of the endothelium for metabolic support. Different components of the media interact with convected molecules: medial smooth muscle cells take up numerous molecules via scavenger receptors and are capable of phagocytosis of macro/micro particles. The outer layers-the highly microvascularized innervated adventitia and perivascular adipose tissue-are also involved in the clearance functions of the media: the adventitia is the seat of immune response development, inward angiogenesis, macromolecular lymphatic drainage, and neuronal stimulation. Consequently, the clearance functions of the arterial wall are physiologically essential, but also may favor the development of arterial wall pathologies. This review describes how the walls of large conductance arteries have acquired physiological clearance functions, how this is determined by the attributes of the endothelial barrier, governed by endocytic and phagocytic capacities of smooth muscle cells, impacting adventitial functions, and the role of these clearance functions in arterial wall diseases.
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Dehe L, Mousa SA, Aboryag N, Shaqura M, Beyer A, Schäfer M, Treskatsch S. Identification of Mineralocorticoid Receptors, Aldosterone, and Its Processing Enzyme CYP11B2 on Parasympathetic and Sympathetic Neurons in Rat Intracardiac Ganglia. Front Neuroanat 2022; 15:802359. [PMID: 35087382 PMCID: PMC8786913 DOI: 10.3389/fnana.2021.802359] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 12/13/2021] [Indexed: 11/13/2022] Open
Abstract
Recent interest has focused on the mineralocorticoid receptor (MR) and its impact on the myocardium and the performance of the heart. However, there is a lack of evidence about MR expression and its endogenous ligand aldosterone synthesis with specific regard to the intrinsic cardiac nervous system. Therefore, we looked for evidence of MR and aldosterone in sympathetic and parasympathetic neurons of intracardiac ganglia. Tissue samples from rat heart atria were subjected to conventional reverse-transcriptase polymerase chain reaction (PCR), Western blot, and double immunofluorescence confocal analysis of MR, corticosterone-inactivating enzyme 11β-hydroxysteroid-dehydrogenase-2 (11β-HSD2), aldosterone, and its processing enzyme CYP11B2 together with the neuronal markers vesicular acetylcholine transporter (VAChT) and tyrosine hydroxylase (TH). Our results demonstrated MR, 11β-HSD2, and CYP11B2 specific mRNA and protein bands in rat heart atria. Double immunofluorescence labeling revealed coexpression of MR immunoreactivity with VAChT in large diameter parasympathetic principal neurons. In addition, MR immunoreactivity was identified in TH-immunoreactive small intensely fluorescent (SIF) cells and in nearby VAChT- and TH-immunoreactive nerve terminals. Interestingly, the aldosterone and its synthesizing enzyme CYP11B2 and 11β-HSD2 colocalized in MR– immunoreactive neurons of intracardiac ganglia. Overall, this study provides first evidence for the existence of not only local expression of MR, but also of 11β-HSD2 and aldosterone with its processing enzyme CYP11B2 in the neurons of the cardiac autonomic nervous system, suggesting a possible modulatory role of the mineralocorticoid system on the endogenous neuronal activity on heart performance.
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Affiliation(s)
- Lukas Dehe
- Department of Anesthesiology and Intensive Care Medicine, Charité Campus Benjamin Franklin, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität and Humboldt Universität zu Berlin, Berlin, Germany
| | - Shaaban A. Mousa
- Department of Anesthesiology and Intensive Care Medicine, Charité Campus Benjamin Franklin, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität and Humboldt Universität zu Berlin, Berlin, Germany
- *Correspondence: Shaaban A. Mousa,
| | - Noureddin Aboryag
- Department of Anesthesiology and Intensive Care Medicine, Charité Campus Benjamin Franklin, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität and Humboldt Universität zu Berlin, Berlin, Germany
| | - Mohammed Shaqura
- Department of Anesthesiology and Intensive Care Medicine, Charité Campus Benjamin Franklin, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität and Humboldt Universität zu Berlin, Berlin, Germany
| | - Antje Beyer
- Department of Anaesthesiology, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Michael Schäfer
- Department of Anesthesiology and Intensive Care Medicine, Charité Campus Benjamin Franklin, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität and Humboldt Universität zu Berlin, Berlin, Germany
| | - Sascha Treskatsch
- Department of Anesthesiology and Intensive Care Medicine, Charité Campus Benjamin Franklin, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität and Humboldt Universität zu Berlin, Berlin, Germany
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Zhang J, Yuan HK, Chen S, Zhang ZR. Detrimental or beneficial: Role of endothelial ENaC in vascular function. J Cell Physiol 2021; 237:29-48. [PMID: 34279047 DOI: 10.1002/jcp.30505] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 06/29/2021] [Accepted: 07/01/2021] [Indexed: 12/19/2022]
Abstract
In the past, it was believed that the expression of the epithelial sodium channel (ENaC) was restricted to epithelial tissues, such as the distal nephron, airway, sweat glands, and colon, where it is critical for sodium homeostasis. Over the past two decades, this paradigm has shifted due to the finding that ENaC is also expressed in various nonepithelial tissues, notably in vascular endothelial cells. In this review, the recent findings of the expression, regulation, and function of the endothelial ENaC (EnNaC) are discussed. The expression of EnNaC subunits is reported in a variety of endothelial cell lines and vasculatures, but this is controversial across different species and vessels and is not a universal finding in all vascular beds. The expression density of EnNaC is very faint compared to ENaC in the epithelium. To date, little is known about the regulatory mechanism of EnNaC. Through it can be regulated by aldosterone, the detailed downstream signaling remains elusive. EnNaC responds to increased extracellular sodium with the feedforward activation mechanism, which is quite different from the Na+ self-inhibition mechanism of ENaC. Functionally, EnNaC was shown to be a determinant of cellular mechanics and vascular tone as it can sense shear stress, and its activation or insertion into plasma membrane causes endothelial stiffness and reduced nitric oxide production. However, in some blood vessels, EnNaC is essential for maintaining the integrity of endothelial barrier function. In this context, we discuss the possible reasons for the distinct role of EnNaC in vasculatures.
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Affiliation(s)
- Jun Zhang
- School of Biomedical Sciences and Li Ka Shing Institute of Health Science, The Chinese University of Hong Kong, Hong Kong, China
| | - Hui-Kai Yuan
- Department of General Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Shuo Chen
- Department of Biopharmaceutical Sciences, School of Pharmacy, Harbin Medical University (Daqing), Daqing, China
| | - Zhi-Ren Zhang
- Departments of Pharmacy and Cardiology, Harbin Medical University Cancer Hospital, Institute of Metabolic Disease, Heilongjiang Academy of Medical Science, Heilongjiang Key Laboratory for Metabolic Disorder & Cancer Related Cardiovascular Diseases, NHC Key Laboratory of Cell Transplantation, Harbin Medical University & Key Laboratories of Education Ministry for Myocardial Ischemia Mechanism and Treatment, Harbin, China
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Aldosterone contributes to hypertension in male mice inducibly overexpressing human endothelin-1 in endothelium. J Hypertens 2021; 39:1908-1917. [PMID: 34039912 DOI: 10.1097/hjh.0000000000002880] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Mechanisms of blood pressure (BP) regulation by endothelin (ET)-1 produced by endothelial cells are complex and remain unclear. Long-term exposure to human ET-1 (hET-1) in mice inducibly overexpressing hET-1 in the endothelium (ieET-1) caused sustained BP elevation. ET-1 has been shown to stimulate the release of aldosterone. Whether aldosterone plays a role in hET-1 overexpression-induced BP elevation and vessel injury is unknown. METHOD Nine- to 12-week-old male ieET-1 mice and control mice expressing a tamoxifen-inducible Cre recombinase (CreERT2) in the endothelial cells (ieCre) were treated with tamoxifen for 5 days and studied 3 months later. RESULTS Endothelial hET-1 overexpression increased plasma aldosterone levels, which was reversed by 2-week treatment with atrasentan, an endothelin type A receptors blocker. Aldosterone synthase and cryptochrome 2 adrenal cortex mRNA expression was decreased in ieET-1 mice. Two-week treatment with eplerenone, a mineralocorticoid receptor antagonist, reduced systolic BP by 10 mmHg in ieET-1 mice during rest time. Saline challenge-induced sodium excretion and renal cortex thiazide-sensitive sodium-chloride cotransporter mRNA expression were decreased in ieET-1 mice. The sensitivity of mesenteric arteries to contraction by norepinephrine was increased in ieET-1 mice, and was abrogated by eplerenone treatment, whereas sensitivity of endothelium-independent relaxation responses to sodium nitroprusside was enhanced. Resistance artery remodeling was reduced in eplerenone-treated ieET-1 vs. ieET-1 and ieCre mice. CONCLUSION These results demonstrate that aldosterone contributes to BP elevation and vascular norepinephrine sensitivity and remodeling caused by hET-1 overexpression in endothelium in mice.
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Yamakawa S, Homma T, Yamada M, Igawa Y, Yoshimura M. [Pharmacological profile, clinical efficacy, and safety of esaxerenone (Minnebro ® tablets 1.25 mg, 2.5 mg, 5 mg)]. Nihon Yakurigaku Zasshi 2020; 155:340-350. [PMID: 32879177 DOI: 10.1254/fpj.20016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Esaxerenone is a novel non-steroidal mineralocorticoid receptor antagonisit (MR blocker), whose unique binding to the MR-ligand domain yields a stronger MR antagonistic effect and higher selectivity than existing MR antagonisits. Esaxerenone was approved for the treatment of hypertension in Japan in January 2019. Esaxerenone suppresses the reduction of urinary Na+/K+ ratio in adrenalectomized rats and blood pressure increase, proteinuria, and renal tissue lesions in salt-sensitive hypertensive rats-all in a dose-dependent manner. Esaxerenone is rapidly absorbed and reaches intracellular targets because of its high membrane permeability, exhibits high bioavailability with small interindividual exposure variation, and is metabolized via several pathways (e.g., oxidation, glucuronidation, and hydrolysis), which is associated with low drug-drug interaction risk. As esaxerenone is slightly excreted into urine, its exposure is similar between elderly and non-elderly patients, and between patients with normal and moderately deteriorated renal function. Given its 19-hour half-life, once-daily administration would have a sustainable antihypertensive effect. The ESAX-HTN phase 3 study demonstrated the non-inferiority of esaxerenone's antihypertensive effect versus that of eplerenone in essential hypertension. Another study showed a stable antihypertensive effect for 52 weeks as monotherapy or combination therapy. In hypertensive patients with moderate impairment or both type 2 diabetes and albuminuria treated with a renin-angiotensin system inhibitor, esaxerenone elicited a stable antihypertensive effect and manageable hyperkalemia incidence with titration from a low dose and monitoring including serum potassium. Thus, with careful monitoring of serum potassium, esaxerenone can be administered to patients with moderate renal impairment or both diabetes and albuminuria.
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Affiliation(s)
- Satoru Yamakawa
- Clinical Development Department III, Daiichi Sankyo Co., Ltd
| | - Tsuyoshi Homma
- Global Project Management Department, Daiichi Sankyo Co., Ltd
| | - Makiko Yamada
- Drug Metabolism & Pharmacokinetics Research Laboratories, Daiichi Sankyo Co., Ltd
| | - Yoshiyuki Igawa
- Quantitative Clinical Pharmacology Department, Daiichi Sankyo Co., Ltd
| | - Motonobu Yoshimura
- Translational Medicine Function, R & D Division, Daiichi Sankyo Co., Ltd
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Aldosterone Synthase in Peripheral Sensory Neurons Contributes to Mechanical Hypersensitivity during Local Inflammation in Rats. Anesthesiology 2020; 132:867-880. [DOI: 10.1097/aln.0000000000003127] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
Background
Recent emerging evidence suggests that extra-adrenal synthesis of aldosterone occurs (e.g., within the failing heart and in certain brain areas). In this study, the authors investigated evidence for a local endogenous aldosterone production through its key processing enzyme aldosterone synthase within peripheral nociceptive neurons.
Methods
In male Wistar rats (n = 5 to 8 per group) with Freund’s complete adjuvant hind paw inflammation, the authors examined aldosterone, aldosterone synthase, and mineralocorticoid receptor expression in peripheral sensory neurons using quantitative reverse transcriptase–polymerase chain reaction, Western blot, immunohistochemistry, and immunoprecipitation. Moreover, the authors explored the nociceptive behavioral changes after selective mineralocorticoid receptor antagonist, canrenoate-K, or specific aldosterone synthase inhibitor application.
Results
In rats with Freund’s complete adjuvant–induced hind paw inflammation subcutaneous and intrathecal application of mineralocorticoid receptor antagonist, canrenoate-K, rapidly and dose-dependently attenuated nociceptive behavior (94 and 48% reduction in mean paw pressure thresholds, respectively), suggesting a tonic activation of neuronal mineralocorticoid receptors by an endogenous ligand. Indeed, aldosterone immunoreactivity was abundant in peptidergic nociceptive neurons of dorsal root ganglia and colocalized predominantly with its processing enzyme aldosterone synthase and mineralocorticoid receptors. Moreover, aldosterone and its synthesizing enzyme were significantly upregulated in peripheral sensory neurons under inflammatory conditions. The membrane mineralocorticoid receptor consistently coimmunoprecipitated with endogenous aldosterone, confirming a functional link between mineralocorticoid receptors and its endogenous ligand. Importantly, inhibition of endogenous aldosterone production in peripheral sensory neurons by a specific aldosterone synthase inhibitor attenuated nociceptive behavior after hind paw inflammation (a 32% reduction in paw pressure thresholds; inflammation, 47 ± 2 [mean ± SD] vs. inflammation + aldosterone synthase inhibitor, 62 ± 2).
Conclusions
Local production of aldosterone by its processing enzyme aldosterone synthase within peripheral sensory neurons contributes to ongoing mechanical hypersensitivity during local inflammation via intrinsic activation of neuronal mineralocorticoid receptors.
Editor’s Perspective
What We Already Know about This Topic
What This Article Tells Us That Is New
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Lim S, Halandras PM, Bechara C, Aulivola B, Crisostomo P. Contemporary Management of Acute Mesenteric Ischemia in the Endovascular Era. Vasc Endovascular Surg 2018; 53:42-50. [DOI: 10.1177/1538574418805228] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Objective: Acute mesenteric ischemia is a rare disease entity associated with high morbidity and mortality. Disparate etiologies and nonspecific symptoms make the diagnosis challenging and often result in delayed diagnosis and intervention. Open laparotomy with mesenteric revascularization and resection of necrotic bowel has been considered the gold standard of care. With recent advances in percutaneous catheter-directed techniques, multiple retrospective studies have demonstrated the outcomes of endovascular therapy. Herein, we review the etiology, presentation, and diagnosis of acute mesenteric ischemia with contemporary outcomes associated with both open and endovascular treatments. Methods: The PubMed electronic database was queried in the English language using the search words mesenteric, acute ischemia, embolism, thromboembolism, thrombosis, revascularization, and endovascular in various combinations. Abstracts of the relevant titles were examined to confirm their relevance and the full articles then extracted. References from extracted articles were checked for any additional relevant articles. This systematic review encompassed literature for the past 5 years (between 2011 and 2016). Results: Early diagnosis and intervention improves acute mesenteric ischemia outcomes. Early restoration of mesenteric flow minimizes morbidity and mortality. In comparison to open laparotomy with mesenteric revascularization and resection of necrotic bowel, several retrospective studies using administrative data and single-center chart reviews demonstrate noninferior outcomes of an endovascular first approach in acute arterial mesenteric occlusion. Conclusions: For acute mesenteric arterial occlusive disease, both endovascular and open revascularization techniques are viable options. Although there is lack of level 1 evidence, single-center retrospective studies and administrative database studies demonstrated that an endovascular first approach may have improved outcomes in the immediate postoperative period. However, selection and other bias in these studies necessitate the need for definitive randomized prospective studies between endovascular and open mesenteric intervention. In contrast, mesenteric venous thrombosis may be treated with systemic anticoagulation without surgical revascularization. Catheter-directed thrombectomy and thrombolysis can be considered at the discretion of the clinician.
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Affiliation(s)
- Sungho Lim
- Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, Loyola University Chicago, Stritch School of Medicine, Maywood, IL, USA
| | - Pegge M. Halandras
- Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, Loyola University Chicago, Stritch School of Medicine, Maywood, IL, USA
| | - Carlos Bechara
- Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, Loyola University Chicago, Stritch School of Medicine, Maywood, IL, USA
| | - Bernadette Aulivola
- Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, Loyola University Chicago, Stritch School of Medicine, Maywood, IL, USA
| | - Paul Crisostomo
- Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, Loyola University Chicago, Stritch School of Medicine, Maywood, IL, USA
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Bamberg K, Johansson U, Edman K, William-Olsson L, Myhre S, Gunnarsson A, Geschwindner S, Aagaard A, Björnson Granqvist A, Jaisser F, Huang Y, Granberg KL, Jansson-Löfmark R, Hartleib-Geschwindner J. Preclinical pharmacology of AZD9977: A novel mineralocorticoid receptor modulator separating organ protection from effects on electrolyte excretion. PLoS One 2018; 13:e0193380. [PMID: 29474466 PMCID: PMC5825103 DOI: 10.1371/journal.pone.0193380] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2017] [Accepted: 02/11/2018] [Indexed: 11/23/2022] Open
Abstract
Excess mineralocorticoid receptor (MR) activation promotes target organ dysfunction, vascular injury and fibrosis. MR antagonists like eplerenone are used for treating heart failure, but their use is limited due to the compound class-inherent hyperkalemia risk. Here we present evidence that AZD9977, a first-in-class MR modulator shows cardio-renal protection despite a mechanism-based reduced liability to cause hyperkalemia. AZD9977 in vitro potency and binding mode to MR were characterized using reporter gene, binding, cofactor recruitment assays and X-ray crystallopgraphy. Organ protection was studied in uni-nephrectomised db/db mice and uni-nephrectomised rats administered aldosterone and high salt. Acute effects of single compound doses on urinary electrolyte excretion were tested in rats on a low salt diet. AZD9977 and eplerenone showed similar human MR in vitro potencies. Unlike eplerenone, AZD9977 is a partial MR antagonist due to its unique interaction pattern with MR, which results in a distinct recruitment of co-factor peptides when compared to eplerenone. AZD9977 dose dependently reduced albuminuria and improved kidney histopathology similar to eplerenone in db/db uni-nephrectomised mice and uni-nephrectomised rats. In acute testing, AZD9977 did not affect urinary Na+/K+ ratio, while eplerenone increased the Na+/K+ ratio dose dependently. AZD9977 is a selective MR modulator, retaining organ protection without acute effect on urinary electrolyte excretion. This predicts a reduced hyperkalemia risk and AZD9977 therefore has the potential to deliver a safe, efficacious treatment to patients prone to hyperkalemia.
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MESH Headings
- Administration, Oral
- Aldosterone
- Animals
- Benzoates/chemistry
- Benzoates/pharmacokinetics
- Benzoates/pharmacology
- Cell Line, Tumor
- Dose-Response Relationship, Drug
- Drug Evaluation, Preclinical
- Eplerenone
- Humans
- Kidney/drug effects
- Kidney/metabolism
- Kidney/pathology
- Male
- Mice, Mutant Strains
- Mineralocorticoid Receptor Antagonists/chemistry
- Mineralocorticoid Receptor Antagonists/pharmacokinetics
- Mineralocorticoid Receptor Antagonists/pharmacology
- Molecular Structure
- Oxazines/chemistry
- Oxazines/pharmacokinetics
- Oxazines/pharmacology
- Potassium/urine
- Rats, Sprague-Dawley
- Receptors, Mineralocorticoid/genetics
- Receptors, Mineralocorticoid/metabolism
- Renal Insufficiency, Chronic/drug therapy
- Renal Insufficiency, Chronic/metabolism
- Renal Insufficiency, Chronic/pathology
- Sodium/urine
- Sodium, Dietary
- Spironolactone/analogs & derivatives
- Spironolactone/chemistry
- Spironolactone/pharmacokinetics
- Spironolactone/pharmacology
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Affiliation(s)
- Krister Bamberg
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Ulrika Johansson
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Karl Edman
- Discovery Sciences, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Lena William-Olsson
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Susanna Myhre
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Anders Gunnarsson
- Discovery Sciences, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Stefan Geschwindner
- Discovery Sciences, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Anna Aagaard
- Discovery Sciences, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Anna Björnson Granqvist
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Frédéric Jaisser
- Centre de Recherche des Cordeliers, INSERM U1138 Team 1, Paris, France
| | - Yufeng Huang
- Division of Nephrology & Hypertension, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Kenneth L. Granberg
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Rasmus Jansson-Löfmark
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Judith Hartleib-Geschwindner
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
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11
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Yamada M, Takei M, Suzuki E, Takakusa H, Kotsuma M, Washio T, Murayama N, Inoue SI, Izumi T. Pharmacokinetics, distribution, and disposition of esaxerenone, a novel, highly potent and selective non-steroidal mineralocorticoid receptor antagonist, in rats and monkeys. Xenobiotica 2016; 47:1090-1103. [PMID: 27866463 DOI: 10.1080/00498254.2016.1263766] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
1. Esaxerenone (CS-3150) is a novel non-steroidal mineralocorticoid receptor antagonist. The pharmacokinetics, tissue distribution, excretion, and metabolism of esaxerenone were evaluated in rats and monkeys. 2. Following intravenous dosing of esaxerenone at 0.1-3 mg/kg, the total body clearance and the volume of distribution were 3.53-6.69 mL/min/kg and 1.47-2.49 L/kg, respectively, in rats, and 2.79-3.69 mL/min/kg and 1.34-1.54 L/kg, respectively, in monkeys. The absolute oral bioavailability was 61.0-127% in rats and 63.7-73.8% in monkeys. 3. After oral administration of [14C]esaxerenone, the radioactivity was distributed widely to tissues, with the exception of a low distribution to the central nervous system. Both in rats and in monkeys, following oral administration of [14C]esaxerenone the main excretion route of the radioactivity was feces. 4. Five initial metabolic pathways in rats and monkeys were proposed to be N-dealkylation, carboxylation, hydroxymethylation, O-glucuronidation, and O-sulfation. The oxidized metabolism was predominant in rats, while both oxidation and glucuronidation were predominant in monkeys.
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Affiliation(s)
- Makiko Yamada
- a Drug Metabolism and Pharmacokinetics Research Laboratories, Daiichi Sankyo Co., Ltd. , Tokyo , Japan
| | - Makoto Takei
- a Drug Metabolism and Pharmacokinetics Research Laboratories, Daiichi Sankyo Co., Ltd. , Tokyo , Japan
| | - Eiko Suzuki
- a Drug Metabolism and Pharmacokinetics Research Laboratories, Daiichi Sankyo Co., Ltd. , Tokyo , Japan
| | - Hideo Takakusa
- a Drug Metabolism and Pharmacokinetics Research Laboratories, Daiichi Sankyo Co., Ltd. , Tokyo , Japan
| | - Masakatsu Kotsuma
- a Drug Metabolism and Pharmacokinetics Research Laboratories, Daiichi Sankyo Co., Ltd. , Tokyo , Japan
| | - Takuo Washio
- a Drug Metabolism and Pharmacokinetics Research Laboratories, Daiichi Sankyo Co., Ltd. , Tokyo , Japan
| | - Nobuyuki Murayama
- a Drug Metabolism and Pharmacokinetics Research Laboratories, Daiichi Sankyo Co., Ltd. , Tokyo , Japan
| | - Shin-Ichi Inoue
- a Drug Metabolism and Pharmacokinetics Research Laboratories, Daiichi Sankyo Co., Ltd. , Tokyo , Japan
| | - Takashi Izumi
- a Drug Metabolism and Pharmacokinetics Research Laboratories, Daiichi Sankyo Co., Ltd. , Tokyo , Japan
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12
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Dinh Cat AN, Friederich-Persson M, White A, Touyz RM. Adipocytes, aldosterone and obesity-related hypertension. J Mol Endocrinol 2016; 57:F7-F21. [PMID: 27357931 DOI: 10.1530/jme-16-0025] [Citation(s) in RCA: 43] [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] [Received: 04/29/2016] [Accepted: 05/09/2016] [Indexed: 12/15/2022]
Abstract
Understanding the mechanisms linking obesity with hypertension is important in the current obesity epidemic as it may improve therapeutic interventions. Plasma aldosterone levels are positively correlated with body mass index and weight loss in obese patients is reported to be accompanied by decreased aldosterone levels. This suggests a relationship between adipose tissue and the production/secretion of aldosterone. Aldosterone is synthesized principally by the adrenal glands, but its production may be regulated by many factors, including factors secreted by adipocytes. In addition, studies have reported local synthesis of aldosterone in extra-adrenal tissues, including adipose tissue. Experimental studies have highlighted a role for adipocyte-secreted aldosterone in the pathogenesis of obesity-related cardiovascular complications via the mineralocorticoid receptor. This review focuses on how aldosterone secretion may be influenced by adipose tissue and the importance of these mechanisms in the context of obesity-related hypertension.
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Affiliation(s)
- Aurelie Nguyen Dinh Cat
- Institute of Cardiovascular and Medical SciencesBHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, UK
| | - Malou Friederich-Persson
- Institute of Cardiovascular and Medical SciencesBHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, UK
| | - Anna White
- Institute of Cardiovascular and Medical SciencesBHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, UK
| | - Rhian M Touyz
- Institute of Cardiovascular and Medical SciencesBHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, UK
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13
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Bogacz A, Bartkowiak-Wieczorek J, Procyk D, Seremak-Mrozikiewicz A, Majchrzycki M, Dziekan K, Bienert A, Czerny B. Analysis of the gene polymorphism of aldosterone synthase (CYP11B2) and atrial natriuretic peptide (ANP) in women with preeclampsia. Eur J Obstet Gynecol Reprod Biol 2015; 197:11-5. [PMID: 26686590 DOI: 10.1016/j.ejogrb.2015.11.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 10/06/2015] [Accepted: 11/17/2015] [Indexed: 01/14/2023]
Abstract
OBJECTIVE Preeclampsia (PE) is a major cause of mortality of mothers, fetuses and newborns around the world. The etiology of preeclampsia has not yet been clarified, but many studies indicate a multifactorial basis of PE. Aldosterone synthase (CYP11B2) is responsible for synthesis of aldosterone responsible for regulating blood pressure. Similarly, natriuretic peptide (ANP) regulates blood pressure through a variety of mechanisms affecting the sodium concentration and the amount of extracellular fluid. Currently, attention is paid to the role of the polymorphisms in the expression level of these genes. The aim of the study was to determine the frequencies of genotypes and alleles for polymorphisms of -344C>T CYP11B2 gene and 2238T>C ANP gene in women with preeclampsia and healthy pregnant women from the Caucasian population. STUDY DESIGN The study included a group of 165 pregnant women (59 women with preeclampsia and 109 healthy pregnant women). DNA was extracted from peripheral blood. Determination of the polymorphism of -344C>T CYP11B2 gene and 2238T>C ANP gene was performed by PCR-RFLP method. RESULTS The results showed that the frequencies of the TC and CC genotypes of 2238T>C polymorphism in ANP gene were significantly higher in patients with PE compared to control group. For -344C>T polymorphism of CYP11B2 gene, the frequency of TT genotype was significantly higher in patients with hypertension than in controls (32.2% vs. 23.58%). CONCLUSIONS Our findings showed that gene polymorphism of CYP11B2 (-344C>T) and ANP (2238T>C) may be associated with developing PE during pregnancy.
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Affiliation(s)
- Anna Bogacz
- Laboratory of Experimental Pharmacogenetics, Department of Clinical Pharmacy and Biopharmacy, University of Medical Sciences, Poznan, Poland; Department of Stem Cells and Regenerative Medicine, Institute of Natural Fibres and Medicinal Plants, Poznan, Poland.
| | - Joanna Bartkowiak-Wieczorek
- Laboratory of Experimental Pharmacogenetics, Department of Clinical Pharmacy and Biopharmacy, University of Medical Sciences, Poznan, Poland
| | - Danuta Procyk
- Department of Laboratory Diagnostics, Greater Poland Cancer Centre, Poznan, Poland
| | - Agnieszka Seremak-Mrozikiewicz
- Division of Perinatology and Women's Diseases, Poznan University of Medical Sciences, Poznan, Poland; Department of Pharmacology and Phytochemistry, Institute of Natural Fibres and Medicinal Plants, Poznan, Poland
| | - Marian Majchrzycki
- Department of Rehabilitation, Poznan University of Medical Sciences, Poznan, Poland
| | - Karolina Dziekan
- Department of Stem Cells and Regenerative Medicine, Institute of Natural Fibres and Medicinal Plants, Poznan, Poland
| | - Agnieszka Bienert
- Laboratory of Experimental Pharmacogenetics, Department of Clinical Pharmacy and Biopharmacy, University of Medical Sciences, Poznan, Poland
| | - Bogusław Czerny
- Department of Stem Cells and Regenerative Medicine, Institute of Natural Fibres and Medicinal Plants, Poznan, Poland; Department of General Pharmacology and Pharmacoeconomics, Pomeranian Medical University, Szczecin, Poland
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14
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Jeggle P, Hofschröer V, Maase M, Bertog M, Kusche‐Vihrog K. Aldosterone synthase knockout mouse as a model for sodium‐induced endothelial sodium channel up‐regulation in vascular endothelium. FASEB J 2015; 30:45-53. [DOI: 10.1096/fj.14-259606] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 08/13/2015] [Indexed: 12/31/2022]
Affiliation(s)
- Pia Jeggle
- Institute of Physiology II, University of MunsterMunsterGermany
| | | | - Martina Maase
- Institute of Physiology II, University of MunsterMunsterGermany
| | - Marko Bertog
- Institut für Zelluläre und Molekulare Physiologie, Friedrich‐Alexander Universität Erlangen‐NürnbergErlangenGermany
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15
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Pharmacological profile of CS-3150, a novel, highly potent and selective non-steroidal mineralocorticoid receptor antagonist. Eur J Pharmacol 2015; 761:226-34. [PMID: 26073023 DOI: 10.1016/j.ejphar.2015.06.015] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2015] [Revised: 06/03/2015] [Accepted: 06/08/2015] [Indexed: 11/22/2022]
Abstract
The present study was designed to characterize the pharmacological profile of CS-3150, a novel non-steroidal mineralocorticoid receptor antagonist. In the radioligand-binding assay, CS-3150 inhibited (3)H-aldosterone binding to mineralocorticoid receptor with an IC50 value of 9.4nM, and its potency was superior to that of spironolactone and eplerenone, whose IC50s were 36 and 713nM, respectively. CS-3150 also showed at least 1000-fold higher selectivity for mineralocorticoid receptor over other steroid hormone receptors, glucocorticoid receptor, androgen receptor and progesterone receptor. In the reporter gene assay, CS-3150 inhibited aldosterone-induced transcriptional activation of human mineralocorticoid receptor with an IC50 value of 3.7nM, and its potency was superior to that of spironolactone and eplerenone, whose IC50s were 66 and 970nM, respectively. CS-3150 had no agonistic effect on mineralocorticoid receptor and did not show any antagonistic or agonistic effect on glucocorticoid receptor, androgen receptor and progesterone receptor even at the high concentration of 5μM. In adrenalectomized rats, single oral administration of CS-3150 suppressed aldosterone-induced decrease in urinary Na(+)/K(+) ratio, an index of in vivo mineralocorticoid receptor activation, and this suppressive effect was more potent and longer-lasting than that of spironolactone and eplerenone. Chronic treatment with CS-3150 inhibited blood pressure elevation induced by deoxycorticosterone acetate (DOCA)/salt-loading to rats, and this antihypertensive effect was more potent than that of spironolactone and eplerenone. These findings indicate that CS-3150 is a selective and highly potent mineralocorticoid receptor antagonist with long-lasting oral activity. This agent could be useful for the treatment of hypertension, cardiovascular and renal disorders.
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16
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Feldman RD, Gros R. Vascular effects of aldosterone: sorting out the receptors and the ligands. Clin Exp Pharmacol Physiol 2014; 40:916-21. [PMID: 23902478 DOI: 10.1111/1440-1681.12157] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 07/23/2013] [Accepted: 07/29/2013] [Indexed: 01/27/2023]
Abstract
Aldosterone has actions far beyond its role as a renal regulator of sodium reabsorption, and broader mechanisms of action than simply a transcriptional regulator. Aldosterone has a number of vascular effects, including regulation of vascular reactivity and vascular growth and/or development. Aldosterone-mediated effects on vascular reactivity reflect a balance between its endothelial-dependent vasodilator effects and its direct smooth muscle vasoconstrictor effects. The endothelial vasodilator effects of aldosterone are mediated by phosphatidylinositol 3-kinase-dependent activation of nitric oxide synthase. G-Protein oestrogen receptor (GPER) is a recently recognized G-protein coupled receptor (GPCR) that is activated by steroid hormones. It was first recognized as the GPCR mediating the rapid effects of oestrogens. Activation of GPER also mediates at least some of the vascular effects of aldosterone in smooth muscle and endothelial cells. In vascular endothelial cells, aldosterone activation of GPER mediates vasodilation. In contrast, activation of endothelial mineralocorticoid receptors has been linked to enhanced vasoconstrictor and/or impaired vasodilator responses.
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Affiliation(s)
- Ross D Feldman
- Departments of Medicine and of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada; Vascular Biology Research Group, Robarts Research Institute, London, ON, Canada
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17
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Maron BA, Leopold JA. The role of the renin-angiotensin-aldosterone system in the pathobiology of pulmonary arterial hypertension (2013 Grover Conference series). Pulm Circ 2014; 4:200-10. [PMID: 25006439 PMCID: PMC4070776 DOI: 10.1086/675984] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2013] [Accepted: 01/17/2014] [Indexed: 12/20/2022] Open
Abstract
Pulmonary arterial hypertension (PAH) is associated with aberrant pulmonary vascular remodeling that leads to increased pulmonary artery pressure, pulmonary vascular resistance, and right ventricular dysfunction. There is now accumulating evidence that the renin-angiotensin-aldosterone system is activated and contributes to cardiopulmonary remodeling that occurs in PAH. Increased plasma and lung tissue levels of angiotensin and aldosterone have been detected in experimental models of PAH and shown to correlate with cardiopulmonary hemodynamics and pulmonary vascular remodeling. These processes are abrogated by treatment with angiotensin receptor or mineralocorticoid receptor antagonists. At a cellular level, angiotensin and aldosterone activate oxidant stress signaling pathways that decrease levels of bioavailable nitric oxide, increase inflammation, and promote cell proliferation, migration, extracellular matrix remodeling, and fibrosis. Clinically, enhanced renin-angiotensin activity and elevated levels of aldosterone have been detected in patients with PAH, which suggests a role for angiotensin and mineralocorticoid receptor antagonists in the treatment of PAH. This review will examine the current evidence linking renin-angiotensin-aldosterone system activation to PAH with an emphasis on the cellular and molecular mechanisms that are modulated by aldosterone and may be of importance for the pathobiology of PAH.
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Affiliation(s)
- Bradley A. Maron
- Brigham and Women’s Hospital, Division of Cardiovascular Medicine, Boston, Massachusetts, USA
- Veterans Affairs Boston Healthcare System, Department of Cardiology, 1400 VFW Parkway, Boston, Massachusetts, USA
| | - Jane A. Leopold
- Brigham and Women’s Hospital, Division of Cardiovascular Medicine, Boston, Massachusetts, USA
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18
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Korte S, Sträter AS, Drüppel V, Oberleithner H, Jeggle P, Grossmann C, Fobker M, Nofer JR, Brand E, Kusche-Vihrog K. Feedforward activation of endothelial ENaC by high sodium. FASEB J 2014; 28:4015-25. [PMID: 24868010 DOI: 10.1096/fj.14-250282] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Accepted: 05/19/2014] [Indexed: 01/11/2023]
Abstract
Kidney epithelial sodium channels (ENaCs) are known to be inactivated by high sodium concentrations (feedback inhibition). Recently, the endothelial sodium channel (EnNaC) was identified to control the nanomechanical properties of the endothelium. EnNaC-dependent endothelial stiffening reduces the release of nitric oxide, the hallmark of endothelial dysfunction. To study the regulatory impact of sodium on EnNaC, endothelial cells (EA.hy926 and ex vivo mouse endothelium) were incubated in aldosterone-free solutions containing either low (130 mM) or high (150 mM) sodium concentrations. By applying atomic force microscopy-based nanoindentation, an unexpected positive correlation between increasing sodium concentrations and cortical endothelial stiffness was observed, which can be attributed to functional EnNaC. In particular, an acute rise in sodium concentration (+20 mM) was sufficient to increase EnNaC membrane abundance by 90% and stiffening of the endothelial cortex by 18%. Despite the absence of exogenous aldosterone, these effects were prevented by the aldosterone synthase inhibitor FAD286 (100 nM) or the mineralocorticoid receptor (MR)-antagonist spironolactone (100 nM), indicating endogenous aldosterone synthesis and MR-dependent signaling. Interestingly, in the presence of high-sodium concentrations, FAD286 increased the transcription of the MR by 69%. Taken together, a novel feedforward activation of EnNaC by sodium is proposed that contrasts ENaC feedback inhibition in kidney.
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Affiliation(s)
- Stefanie Korte
- Institute of Physiology II, University of Münster, Münster, Germany
| | | | - Verena Drüppel
- Institute of Physiology II, University of Münster, Münster, Germany
| | | | - Pia Jeggle
- Institute of Physiology II, University of Münster, Münster, Germany
| | - Claudia Grossmann
- Julius-Bernstein-Institute of Physiology, University Halle-Wittenberg, Halle, Germany
| | - Manfred Fobker
- Center of Laboratory Medicine, University of Münster, Münster, Germany; and
| | - Jerzy-Roch Nofer
- Center of Laboratory Medicine, University of Münster, Münster, Germany; and
| | - Eva Brand
- Internal Medicine D, Department of Nephrology, Hypertension and Rheumatology, University Hospital Muenster, Muenster, Germany
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19
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Talabér G, Jondal M, Okret S. Extra-adrenal glucocorticoid synthesis: immune regulation and aspects on local organ homeostasis. Mol Cell Endocrinol 2013; 380:89-98. [PMID: 23707789 DOI: 10.1016/j.mce.2013.05.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 04/22/2013] [Accepted: 05/07/2013] [Indexed: 12/21/2022]
Abstract
Systemic glucocorticoids (GCs) mainly originate from de novo synthesis in the adrenal cortex under the control of the hypothalamus-pituitary-adrenal (HPA)-axis. However, research during the last 1-2 decades has revealed that additional organs express the necessary enzymes and have the capacity for de novo synthesis of biologically active GCs. This includes the thymus, intestine, skin and the brain. Recent research has also revealed that locally synthesized GCs most likely act in a paracrine or autocrine manner and have significant physiological roles in local homeostasis, cell development and immune cell activation. In this review, we summarize the nature, regulation and known physiological roles of extra-adrenal GC synthesis. We specifically focus on the thymus in which GC production (by both developing thymocytes and epithelial cells) has a role in the maintenance of proper immunological function.
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Affiliation(s)
- Gergely Talabér
- Department of Biosciences and Nutrition, Karolinska Institutet, Novum, SE-141 83 Huddinge, Sweden
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20
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Gros R, Ding Q, Liu B, Chorazyczewski J, Feldman RD. Aldosterone mediates its rapid effects in vascular endothelial cells through GPER activation. Am J Physiol Cell Physiol 2013; 304:C532-40. [PMID: 23283935 DOI: 10.1152/ajpcell.00203.2012] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The importance of the rapid vascular effects of aldosterone is increasingly appreciated. Through these rapid pathways, aldosterone has been shown to regulate vascular contractility, cell growth, and apoptosis. In our most recent studies, we demonstrated the effects of aldosterone on cell growth and contractility in vascular smooth muscle cells. We showed that these effects could occur via activation of the classic mineralocorticoid receptor, as well the recently characterized G protein-coupled estrogen receptor (GPER), initially characterized as an estrogen-specific receptor. However, the mechanisms underlying aldosterone's endothelium-dependent actions are unknown. Furthermore, the ERK regulatory and proapoptotic effects of aldosterone mediated by GPER activation in cultured vascular smooth muscle cells were only apparent when GPER was reintroduced into these cells by gene transfer. Whether GPER activation via aldosterone might be an important regulator in native vascular cells has been questioned. Therefore, to determine the role of GPER in mediating aldosterone's effects on cell growth and vascular reactivity in native cells, we examined rat aortic vascular endothelial cells, a model characterized by persistent robust expression of GPER, but without detectable mineralocorticoid receptor expression. In these endothelial cells, the GPER agonist G1 mediates a rapid increase in ERK phosphorylation that is wholly GPER-dependent, paralleling the actions of aldosterone. The effects of G1 and aldosterone to stimulate ERK phosphorylation paralleled their proapoptotic and antiproliferative effects. In previous studies, we reported that aldosterone mediates a rapid endothelium-dependent vasodilatory effect, antagonistic to its direct vasoconstrictor effect in endothelium-denuded preparations. Using a rat aortic ring/organ bath preparation to determine the GPER dependence of aldosterone's endothelium-dependent vasodilator effects, we demonstrate that aldosterone inhibits phenylephrine-mediated contraction. This vasodilator effect parallels the actions of the GPER agonist G1. Furthermore, the effects of aldosterone were completely ablated by the GPER antagonist G15. These data support an important role of GPER activation in aldosterone-mediated regulation of endothelial cell growth, as well as in aldosterone's endothelium-mediated regulation of vasoreactivity.
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Affiliation(s)
- Robert Gros
- Department of Medicine, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada
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21
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McCurley A, Jaffe IZ. Mineralocorticoid receptors in vascular function and disease. Mol Cell Endocrinol 2012; 350:256-65. [PMID: 21723914 PMCID: PMC3214604 DOI: 10.1016/j.mce.2011.06.014] [Citation(s) in RCA: 121] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 06/10/2011] [Accepted: 06/15/2011] [Indexed: 12/16/2022]
Abstract
The mineralocorticoid receptor (MR), a member of the steroid receptor family, regulates blood pressure by mediating the effects of the hormone aldosterone (Aldo) on renal sodium handling. Over the past decade, it has become clear that MR is expressed in the cardiovascular system and interest has grown in understanding the direct role of the MR in regulating vascular function and contributing to cardiovascular disease. This interest stems from multiple clinical studies in which drugs that decrease MR activation also reduce the incidence of heart attacks, strokes, and mortality out of proportion to modest changes in systemic blood pressure. The presence of functional mineralocorticoid receptors in vascular smooth muscle and endothelial cells is now well established and, while still controversial, data supports the vasculature as an Aldo-responsive tissue. This review summarizes recent advances in our understanding of the role of vascular MR in regulating normal vascular function and in promoting vascular disease. In vitro data, in vivo animal studies, and human data are reviewed suggesting a role for MR-activation in promoting vascular oxidative stress, inhibiting vascular relaxation, and contributing to vessel inflammation, fibrosis, and remodeling. These detrimental vascular effects of MR activation appear to be independent of changes in blood pressure and are synergistic with the presence of endothelial dysfunction or damage. Thus, in humans with underlying cardiovascular disease or cardiovascular risk factors, vascular MR activation may promote vascular aging and atherosclerosis thereby contributing to the pathophysiology of heart attack, stroke, and possibly even hypertension. Further exploration of the molecular mechanisms for the detrimental vascular effects of MR activation has the potential to identify novel therapeutic targets to prevent or treat common cardiovascular disorders.
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Affiliation(s)
- Amy McCurley
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, Massachusetts, USA
| | - Iris Z. Jaffe
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, Massachusetts, USA
- Department of Medicine, Division of Cardiology, Tufts Medical Center, Boston, Massachusetts, USA
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22
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Wu SY, Yu YR, Cai Y, Jia LX, Wang X, Xiao CS, Tang CS, Qi YF. Endogenous aldosterone is involved in vascular calcification in rat. Exp Biol Med (Maywood) 2012; 237:31-7. [DOI: 10.1258/ebm.2011.011175] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Aldosterone (Aldo) is an important active hormone in the renin–angiotensin–aldosterone system and plays a vital role in the development of hypertension, heart failure and other cardiovascular diseases. We aimed to explore the role of endogenous Aldo in aortic calcification in rats. We induced arterial calcification in rats by intramuscular administration of vitamin D3 plus oral nicotine (VDN) and determined calcium content, 45Ca2+ accumulation and activity of alkaline phosphatase (ALP). The mRNA level of osteopontin (OPN) was measured by semi-quantitative reverse transcriptase polymerase chain reaction. Deposition of collagen in the aorta wall was measured by Sirius red staining. The content of angiotensin II (Ang II) and Aldo in plasma and myocardial and vascular tissue was determined by radioimmunoassay. In rats with VDN treatment, von Kossa staining showed calcification in vascular smooth muscle cells and extracellular matrix, and the content of calcium in calcified arteries was 5.8-fold of that in control arteries ( P < 0.01). The accumulation of 45Ca2+ and activity of ALP in calcified aortic tissue was three- and 2.5-fold, respectively, that in control tissue ( P < 0.01). The mRNA expression of OPN was significantly higher, by 58%, in calcified than control tissue ( P < 0.01). Vascular fibrosis was greater in rats with calcified tissue than in control rats. The level of Ang II and Aldo was 58% and 80% higher, respectively, in calcified than control tissue (both P < 0.01). The changes could be significantly improved by treatment with captopril, an angiotensin-converting enzyme inhibitor, and the Aldo receptor antagonist spironolactone. These results suggest that Aldo is an endogenous bioactive factor involved in vascular calcification.
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Affiliation(s)
- Sheng-Ying Wu
- Key Laboratory of Molecular Cardiovascular Science, Ministry of Education
- Department of Physiology and Pathophysiology
| | - Yan-Rong Yu
- Key Laboratory of Molecular Cardiovascular Science, Ministry of Education
- Department of Medical Parasitology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191
| | - Yan Cai
- Key Laboratory of Molecular Cardiovascular Science, Ministry of Education
- Department of Physiology and Pathophysiology
| | - Li-Xin Jia
- Department of Cardiology, the Second Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, China
| | - Xiong Wang
- Department of Physiology and Pathophysiology
| | - Chuan-Shi Xiao
- Department of Cardiology, the Second Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, China
| | - Chao-Shu Tang
- Key Laboratory of Molecular Cardiovascular Science, Ministry of Education
- Department of Physiology and Pathophysiology
| | - Yong-Fen Qi
- Key Laboratory of Molecular Cardiovascular Science, Ministry of Education
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23
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Blaustein MP, Leenen FHH, Chen L, Golovina VA, Hamlyn JM, Pallone TL, Van Huysse JW, Zhang J, Wier WG. How NaCl raises blood pressure: a new paradigm for the pathogenesis of salt-dependent hypertension. Am J Physiol Heart Circ Physiol 2011; 302:H1031-49. [PMID: 22058154 DOI: 10.1152/ajpheart.00899.2011] [Citation(s) in RCA: 175] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Excess dietary salt is a major cause of hypertension. Nevertheless, the specific mechanisms by which salt increases arterial constriction and peripheral vascular resistance, and thereby raises blood pressure (BP), are poorly understood. Here we summarize recent evidence that defines specific molecular links between Na(+) and the elevated vascular resistance that directly produces high BP. In this new paradigm, high dietary salt raises cerebrospinal fluid [Na(+)]. This leads, via the Na(+)-sensing circumventricular organs of the brain, to increased sympathetic nerve activity (SNA), a major trigger of vasoconstriction. Plasma levels of endogenous ouabain (EO), the Na(+) pump ligand, also become elevated. Remarkably, high cerebrospinal fluid [Na(+)]-evoked, locally secreted (hypothalamic) EO participates in a pathway that mediates the sustained increase in SNA. This hypothalamic signaling chain includes aldosterone, epithelial Na(+) channels, EO, ouabain-sensitive α(2) Na(+) pumps, and angiotensin II (ANG II). The EO increases (e.g.) hypothalamic ANG-II type-1 receptor and NADPH oxidase and decreases neuronal nitric oxide synthase protein expression. The aldosterone-epithelial Na(+) channel-EO-α(2) Na(+) pump-ANG-II pathway modulates the activity of brain cardiovascular control centers that regulate the BP set point and induce sustained changes in SNA. In the periphery, the EO secreted by the adrenal cortex directly enhances vasoconstriction via an EO-α(2) Na(+) pump-Na(+)/Ca(2+) exchanger-Ca(2+) signaling pathway. Circulating EO also activates an EO-α(2) Na(+) pump-Src kinase signaling cascade. This increases the expression of the Na(+)/Ca(2+) exchanger-transient receptor potential cation channel Ca(2+) signaling pathway in arterial smooth muscle but decreases the expression of endothelial vasodilator mechanisms. Additionally, EO is a growth factor and may directly participate in the arterial structural remodeling and lumen narrowing that is frequently observed in established hypertension. These several central and peripheral mechanisms are coordinated, in part by EO, to effect and maintain the salt-induced elevation of BP.
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Affiliation(s)
- Mordecai P Blaustein
- Dept. of Physiology, Univ. of Maryland School of Medicine, 655 W. Baltimore St., Baltimore, MD, 21201, USA.
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24
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Taves MD, Gomez-Sanchez CE, Soma KK. Extra-adrenal glucocorticoids and mineralocorticoids: evidence for local synthesis, regulation, and function. Am J Physiol Endocrinol Metab 2011; 301:E11-24. [PMID: 21540450 PMCID: PMC3275156 DOI: 10.1152/ajpendo.00100.2011] [Citation(s) in RCA: 189] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Glucocorticoids and mineralocorticoids are steroid hormones classically thought to be secreted exclusively by the adrenal glands. However, recent evidence has shown that corticosteroids can also be locally synthesized in various other tissues, including primary lymphoid organs, intestine, skin, brain, and possibly heart. Evidence for local synthesis includes detection of steroidogenic enzymes and high local corticosteroid levels, even after adrenalectomy. Local synthesis creates high corticosteroid concentrations in extra-adrenal organs, sometimes much higher than circulating concentrations. Interestingly, local corticosteroid synthesis can be regulated via locally expressed mediators of the hypothalamic-pituitary-adrenal (HPA) axis or renin-angiotensin system (RAS). In some tissues (e.g., skin), these local control pathways might form miniature analogs of the pathways that regulate adrenal corticosteroid production. Locally synthesized glucocorticoids regulate activation of immune cells, while locally synthesized mineralocorticoids regulate blood volume and pressure. The physiological importance of extra-adrenal glucocorticoids and mineralocorticoids has been shown, because inhibition of local synthesis has major effects even in adrenal-intact subjects. In sum, while adrenal secretion of glucocorticoids and mineralocorticoids into the blood coordinates multiple organ systems, local synthesis of corticosteroids results in high spatial specificity of steroid action. Taken together, studies of these five major organ systems challenge the conventional understanding of corticosteroid biosynthesis and function.
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Affiliation(s)
- Matthew D Taves
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada.
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Carvajal CA, Stehr CB, González PA, Riquelme EM, Montero T, Santos MJ, Kalergis AM, Fardella CE. A de novo unequal cross-over mutation between CYP11B1 and CYP11B2 genes causes familial hyperaldosteronism type I. J Endocrinol Invest 2011; 34:140-4. [PMID: 20634641 DOI: 10.1007/bf03347044] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
UNLABELLED Familial hyperaldosteronism type I (FH-I) is an autosomal dominant disorder caused by an unequal cross-over of the gene encoding steroid 11β-hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2), giving rise to a chimeric CYP11B1/CYP11B2 gene that displays aldosterone synthase activity regulated by ACTH instead of angiotensin II. AIM To report an unprecedented case of a de novo unequal crossover mutation between CYP11B1 and CYP11B2 genes causing FH-I. PATIENTS AND METHODS The index case is a 45-yr-old Chilean male diagnosed with primary aldosteronism (PA). All family members were also studied: his biological parents, 1 brother, 6 sisters, 2 daughters, and 1 son. Plasma renin activity, serum aldosterone, and its ratio were measured in all patients. Genetic analyses were performed using long-extension PCR (XL-PCR), DNA sequencing and Southern blot methods. RESULTS PA was diagnosed for the index case, 1 of his daughters, his son but not for his parents or siblings. XLPCR and Southern blotting demonstrated the presence of the chimeric CYP11B1/CYP11B2 gene solely in PA-affected subjects, suggesting a case of a de novo mutation. Sequence analysis showed the unequal cross-over CYP11B1/CYP11B2 at intron 2 (c.2600-273 CYP11B2). We also identified a polymorphism at the same intron (c.2600-145C>A CYP11B2) in the genome of the index case's father. CONCLUSION We describe an unprecedented case of unequal cross-over mutation for the chimeric CYP11B1/CYP11B2 gene causing FH-I, which may be linked to a polymorphism in the index case's father germ line.
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Affiliation(s)
- C A Carvajal
- Endocrinology Department, Faculty of Medicine, Pontificia Universidad Catolica de Chile, Santiago, Chile
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Increased levels of oxidative stress, subclinical inflammation, and myocardial fibrosis markers in primary aldosteronism patients. J Hypertens 2011; 28:2120-6. [PMID: 20683341 DOI: 10.1097/hjh.0b013e32833d0177] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND Patients with primary aldosteronism experience greater left ventricular hypertrophy and a higher frequency of cardiovascular events than do essential hypertensive patients with comparable blood pressure levels. Aldosterone has been correlated with increased oxidative stress, endothelial inflammation, and fibrosis, particularly in patients with heart disease. AIM To evaluate oxidative stress, subclinical endothelial inflammation, and myocardial fibrosis markers in patients with primary aldosteronism and essential hypertension. DESIGN AND INDIVIDUALS: We studied 30 primary aldosteronism patients and 70 control essential hypertensive patients, matched by age, sex and median blood pressure. For all patients, we measured the serum levels of aldosterone, plasma renin activity, malondialdehyde (MDA), xanthine oxidase, metalloproteinase-9, ultrasensitive C-reactive protein and amino terminal propeptides of type I (PINP), and type III procollagen. We also evaluated the effect of PA treatment in 19 PA individuals. RESULTS PA patients showed elevated levels of MDA (1.70 ± 0.53 versus 0.94 ± 0.65 μmol/l, P <0.001) and PINP (81.7 ± 50.6 versus 49.7 ± 27 mg/l, P = 0.002) compared with essential hypertensive controls. We found a positive correlation between MDA, PINP, and the serum aldosterone/plasma renin activity ratio in primary aldosteronism patients. Clinically, treating primary aldosteronism patients decreased MDA and PINP levels. CONCLUSION We detected higher levels of MDA and PINP in primary aldosteronism patients, suggesting increased oxidative stress and myocardial fibrosis in these individuals. Treating primary aldosteronism patients reduced MDA and PINP levels, which may reflect the direct effect of aldosterone greater than endothelial oxidative stress and myocardial fibrosis, possibly mediated by a mineralocorticoid receptor.
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Cachofeiro V, López-Andrés N, Miana M, Martín-Fernández B, de las Heras N, Martínez E, Lahera V, Fortuño MA. Aldosterone and the cardiovascular system: a dangerous association. Horm Mol Biol Clin Investig 2010; 4:539-48. [DOI: 10.1515/hmbci.2010.057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Accepted: 10/11/2010] [Indexed: 11/15/2022]
Abstract
AbstractInitial studies have focussed on the actions of aldosterone in renal electrolyte handling and, as a consequence, blood pressure control. More recently, attention has primarily been focussed on its actions on the heart and vascular system, where it is locally produced. Aldosterone by binding mineralocorticoid receptors causes oxidative stress, fibrosis and triggers an inflammatory response in the cardiovascular system. All these effects could be underlying the role of aldo-sterone on cardiac and vascular remodelling associated with different pathological situations. At the vascular level, aldo-sterone affects endothelial function because administration of aldosterone to rats impaired endothelium-dependent relaxations. In addition, the administration of mineralocorticoid receptor antagonists ameliorates endothelium-dependent relaxation in models of both hypertension and atherosclerosis, and in patients with heart failure. Several mechanisms can participate in this effect, including production of vasoconstrictor factors and a reduction in nitric oxide levels. This reduction can involve both a decrease in its production as well as an increase in its degradation by reactive oxygen species. Aldosterone can produce oxidative stress by the activation of transcription factors such as the NF-κB system, which can also trigger an inflammatory process through the production of different cytokines. At cardiac level, high levels of aldosterone can also adversely impact heart function by producing cardiac hypertrophy, diastolic dysfunction and electrical remodelling through changes in ionic channels. All these effects can explain the beneficial effect of mineralocorticoid blockade in the cardiovascular system.
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Carvajal CA, Herrada AA, Castillo CR, Contreras FJ, Stehr CB, Mosso LM, Kalergis AM, Fardella CE. Primary aldosteronism can alter peripheral levels of transforming growth factor beta and tumor necrosis factor alpha. J Endocrinol Invest 2009; 32:759-65. [PMID: 19605974 DOI: 10.1007/bf03346533] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
UNLABELLED Primary aldosteronism (PA) is the most common secondary cause of hypertension that has recently been implicated in alterations of the immune system and progression of cardiovascular disease. OBJECTIVE To study the cytokines transforming growth factor beta1 (TGF-beta1), tumor necrosis factor alpha (TNF-alpha), and interleukin 10 (IL-10) in patients with PA and essential hypertensives (EH) and evaluate its association with the renin-angiotensin-aldosterone system. PATIENTS AND METHODS We studied 26 PA and 52 EH patients as controls, adjusted by their blood pressure, body mass index, age, and gender. In both groups, PA and EH, we measured serum aldosterone (SA), plasma renin activity (PRA), and cytokines TGF- beta1, TNF-alpha, and IL-10. In addition, 17 PA patients were treated for 6 months with spironolactone, a mineralocorticoid receptor (MR) antagonist. RESULTS PA patients had lower levels of TGF-beta1 (17.6+/-4.1 vs 34.5+/-20.5 pg/ml, p<0.001) and TNF-alpha (17.0+/-4.4 vs 35.6+/-21.7 pg/ml, p<0.001) and similar IL-10 levels (99.7+/-18.7 vs 89.4+/-49.5 pg/ml, p: ns), as compared with EH controls. TGF-beta1 and TNF-alpha levels showed a remarkable correlation with SA/PRA ratio in the total group (PA+EH). The treatment of PA patients with spironolactone increased the TGF-beta1 levels (18.3+/-5.9 to 28.4+/-6.3 pg/ml, p<0.001), while TNF-alpha, and IL-10 remained unchanged. CONCLUSION Our results showed that PA patients have lower TGF-beta1 and TNF-alpha cytokine serum levels than EH. TGF-beta1 levels were restored with spironolactone, showing a MR-dependent regulation. In this way, the chronic aldosterone excess modifies the TGF-beta1 levels, which could produce an imbalance in the immune system homeostasis that may promote an early proinflammatory cardiovascular phenotype.
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Affiliation(s)
- C A Carvajal
- Department of Endocrinology, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
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30
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Ding Q, Gros R, Limbird LE, Chorazyczewski J, Feldman RD. Estradiol-mediated ERK phosphorylation and apoptosis in vascular smooth muscle cells requires GPR 30. Am J Physiol Cell Physiol 2009; 297:C1178-87. [PMID: 19741198 DOI: 10.1152/ajpcell.00185.2009] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Recent studies suggest that the rapid and nongenomic effects of estradiol may be mediated through the G protein-coupled receptor dubbed GPR30 receptor. The present study examines the role of GPR30 versus a classical estrogen receptor (ERalpha) in mediating the growth regulatory effects of estradiol. GPR30 is readily detectable in freshly isolated vascular tissue but barely detectable in cultured vascular smooth muscle cells (VSMC). In freshly isolated aortic tissue, estradiol stimulated extracellular signal-regulated kinases (ERK) phosphorylation. In contrast, in cultured VSMC, where GPR30 expression is significantly reduced, estradiol inhibits ERK phosphorylation. Transfer of the genes encoding GPR30 led to estradiol stimulation of ERK phosphorylation, which is opposite the effects of estradiol in the primary culture of VSMCs. Transduction of the mineralocorticoid receptor (MR) had no effect on estradiol effects on ERK. Estradiol-mediated stimulation of ERK subsequent to heterologous GPR30 expression was pertussis toxin sensitive and phosphoinositide 3-kinase (PI3 kinase) dependent; under these conditions, estradiol also inhibited protein kinase A (PKA). In contrast, in the absence of GPR30 expression in cultured VSMC, estradiol stimulated PKA activity and inhibited ERK phosphorylation. To determine the functional effect of GPR30 (vs. estrogen receptor expression), we assessed estradiol-mediated apoptosis. In the absence of GPR30 expression, estradiol inhibited apoptosis. This effect was enhanced with ERalpha expression. In contrast, with GPR30 expression, estradiol stimulated apoptosis in an ERK-dependent manner. Thus the effect of estradiol on vascular smooth muscle cell apoptosis is likely dependent on the balance between ER-mediated PKA activation and GPR30-mediated PKA inhibition and PI3 kinase activation. Taken together, we postulate that modulation of GPR30 expression or activity may be an important determinant of the effects of estradiol in the vasculature.
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Affiliation(s)
- Qingming Ding
- Department of Vascular Biology Research Group, Robarts Research Institute, University of Western Ontario, London, ON, Canada N6A 5K8
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Cortinovis M, Perico N, Cattaneo D, Remuzzi G. Aldosterone and progression of kidney disease. Ther Adv Cardiovasc Dis 2009; 3:133-43. [PMID: 19171691 DOI: 10.1177/1753944708100409] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Experimental evidence indicates that aldosterone, besides its mineralcorticoid properties, directly contributes to accelerate renal damage through promotion of cell growth, fibrosis and inflammation. As a consequence, attenuation of growth-promoting and fibroproliferative effects of aldosterone might contribute to slow progression of chronic renal injury. Preliminary clinical observations have documented that aldosterone blockers added to angiotensin-converting enzyme inhibitor- and/or angiotensin receptor blocker-based regimens exerted significant antiproteinuric effects in patients with diabetic and nondiabetic nephropathies. Further studies in larger cohorts are now required to definitively address the safety and efficacy of aldosterone antagonism in patients with chronic kidney diseases.
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Affiliation(s)
- Monica Cortinovis
- Department of Medicine and Transplantation, Ospedali Riuniti di Bergamo - Mario Negri Institute for Pharmacological Research, Bergamo, Italy
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32
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Jones JM, Dowling TC, Park JJ, Phares DA, Park JY, Obisesan TO, Brown MD. Differential aerobic exercise-induced changes in plasma aldosterone between African Americans and Caucasians. Exp Physiol 2007; 92:871-9. [PMID: 17483200 PMCID: PMC2729146 DOI: 10.1113/expphysiol.2007.037408] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Aldosterone influences the kidney's regulation of blood pressure (BP), but aldosterone can contribute to the pathogenesis of hypertension. Blood pressure is reduced with aerobic exercise training (AEX), but the extent to which plasma aldosterone (PA) levels change is unclear. The purpose of this study was to determine whether 6 months of AEX changed PA levels, 24 h sodium (Na(+)) excretion and BP in prehypertensive and hypertensive subjects and whether these changes differed according to ethnicity. The study was performed in the Kinesiology Department at the University of Maryland, College Park, and 35 (22 Caucasian; 13 African American) sedentary prehypertensive and hypertensive subjects completed 6 months of AEX. Blood samples were collected under fasting and supine conditions, and PA was measured by radioimmunoassay. In total population aerobic exercise training increased maximal oxygen consumption (24 +/- 0.8 versus 28 +/- 1 ml kg(-1) min(-1), P < 0.001) and decreased PA levels (97 +/- 11 versus 72 +/- 6 pg ml(-1), P = 0.01), body mass index (28 +/- 0.5 versus 28 +/- 0.5 kg m(-2), P = 0.004) and weight (85 +/- 2 versus 83 +/- 2 kg, P = 0.003). Aerobic exercise training decreased PA levels (from 119 +/- 16 to 81 +/- 7 pg ml(-1), P = 0.02) in the Caucasians but there was no change in BP or Na(+) excretion. African American participants had no significant changes in PA levels, BP and Na(+) excretion. Plasma aldosterone levels were 47% lower at baseline (P = 0.01) and 30% lower after AEX (P = 0.04) in African American participants compared with Caucasians. Baseline (P = 0.08) and final PA levels (P = 0.17) did not differ between the two groups after accounting for baseline and final intra-abdominal fat, respectively. The reduction in PA levels with AEX appeared to be driven by the change in PA levels in Caucasian participants. Fat distribution contributed to the ethnic differences in PA levels.
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Affiliation(s)
- Jennifer M Jones
- Department of Kinesiology, University of Maryland, College Park, MD, USA.
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33
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Tanaka K, Ashizawa N, Kawano H, Sato O, Seto S, Nishihara E, Terazono H, Isomoto S, Shinohara K, Yano K. Aldosterone induces circadian gene expression of clock genes in H9c2 cardiomyoblasts. Heart Vessels 2007; 22:254-60. [PMID: 17653520 DOI: 10.1007/s00380-006-0968-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2006] [Accepted: 12/01/2006] [Indexed: 10/23/2022]
Abstract
We examined mRNA expression of the clock genes (Per1, Per2, and Bmal1) and PAI-1 (plasminogen activator inhibitor-1) after aldosterone treatment every 4 h up to 48 h in H9c2 cardiomyoblasts by reverse transcription-polymerase chain reaction. To block the MR (mineralocorticoid receptor), the MR antagonist, spironolactone, was added to the medium 1 h before aldosterone treatment. Aldosterone induced an initial increase and rhythmic expression of Per1, while spironolactone attenuated the acute increase in Per1 mRNA induced by aldosterone. On the other hand, aldosterone did not increase the Per2 mRNA in the acute phase, but thereafter induced a rhythmic expression of Per2. Aldosterone also induced rhythmic expression of Bmal1, a positive element of the clock genes. The rhythm of Bmal1 mRNA was anti-phase of that of Per2 mRNA. Aldosterone induced an acute increase in PAI-1 mRNA, but did not induce rhythmic expression of PAI-1. The present study demonstrated first that aldosterone regulates expression of the clock genes Per1, Per2, and Bmal1, and increases PAI-1 expression in H9c2 cardiomyoblasts. Second, an acute increase in Per1 mRNA after aldosterone treatment is mediated through MR. Third, clock genes are not related to PAI-1 expression in H9c2 cardiomyoblasts.
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Affiliation(s)
- Kyoe Tanaka
- Division of Cardiovascular Medicine, Department of Translational Medical Sciences, Course of Medical and Dental Sciences, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8501, Japan.
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34
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Freel EM, Bernhardt R, Bernhardt M, Ingram M, Ingram R, Wallace AM, Fraser R, Davies E, Connell JMC. Endogenous corticosteroid biosynthesis in subjects after bilateral adrenalectomy. Clin Endocrinol (Oxf) 2007; 66:659-65. [PMID: 17381495 DOI: 10.1111/j.1365-2265.2007.02791.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Corticosteroids can be synthesized in extra-adrenal tissues but the contribution of this to circulating levels in humans is not known. Previous in vitro studies suggest that the 'hybrid' corticosteroid 18-oxocortisol (18-oxoF) is produced from cortisol by aldosterone synthase. We looked for evidence of extra-adrenal production of this and other corticosteroids in 10 subjects stable on long-term glucocorticoid replacement following bilateral adrenalectomy. METHODS In phase 1, patients were maintained on cortisol alone (30 mg/day), in phase 2 dexamethasone (2 mg/day), and in phase 3, both cortisol and dexamethasone. Each phase lasted 3 days. MEASUREMENTS On the last day of each phase, 24-h urine collection was performed for analysis of steroid metabolite excretion [using gas chromatography-mass spectrometry (GCMS)] and plasma aldosterone and renin were measured (by radioimmunoassay). RESULTS Cortisol metabolite excretion rate [tetrahydrocortisone (THE) + tetrahydrocortisol (THF) + allotetrahydrocortisol (aTHF)] fell from 9169 nmol/24 h in phase 1 to 22 nmol/24 h in phase 2, rising to 6843 nmol/24 h in phase 3. Tetrahydroaldosterone (THAldo) excretion was readily detectable and did not alter significantly between phases (26.5, 23.5 and 28.5 nmol/24 h, respectively; P = 0.474). 18-Hydroxycortisol (18-OHF) excretion was easily detectable in phases 1 and 3 (252.5 and 212 nmol/24 h), falling in phase 2 (12 nmol/24 h). 18-oxoF excretion rates were lower but followed a similar pattern (1.62, 0.085 and 1.785 nmol/24 h in phases 1, 2 and 3, respectively). CONCLUSIONS Significant levels of adrenal steroids are found in adrenalectomized subjects. We speculate that this occurs at extra-adrenal sites or in residual adrenal cortex tissue in an ACTH-independent manner. Our data suggest that aldosterone synthase, acting on cortisol, is the source of 18-oxoF and 18-OHF in these subjects. Further studies of corticosteroid production within adrenalectomized subjects, looking for evidence of adrenal regrowth or residual adrenal tissue, are justified.
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Affiliation(s)
- E M Freel
- Glasgow Cardiovascular Research Centre, University of Glasgow, UK
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Gullulu M, Akdag I, Kahvecioglu S, Filiz G, Savci V. Aldosterone blockage in proliferative glomerulonephritis prevents not only fibrosis, but proliferation as well. Ren Fail 2006; 28:509-14. [PMID: 16928621 DOI: 10.1080/08860220600779033] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Studies performed recently have determined that aldosterone has not only a major role in electrolyte and water balance and K excretion, but it also modulates myofibroblast growth in the heart and blood vessels and causes fibrosis. This study investigated the effects of aldosterone blockers in rats with anti-thy 1.1 nephritis, both on proliferation and fibrosis, by comparing it to an angiotensin receptor inhibitor valsartan. Rats with anti-thy 1.1 nephritis were randomly allocated to one of the three following groups of treatment: the control group (group 1); those treated with the aldosterone receptor blocker spironolactone (group 2); and those treated with the ATRB valsartan (group 3). On day 7, the parameters of glomerular fibrosis [transforming growth factor beta, TGF staining areas %], proliferation (Ki-67), and renal damage scores were determined. The TGF-beta and Ki-67 levels of control group were significantly more than the other two groups (p<0.01). The TGF staining areas percentages were significantly decreased compared to control group. The artery, glomerular, and renal injury scores evaluated between the groups were found to be significantly decreased compared to control group. In line with previous studies, this study found that in anti-thy 1.1 mesangioproliferative glomerulonephritis, aldosterone blockage affected proliferation and fibrosis.
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Affiliation(s)
- Mustafa Gullulu
- Department of Nephrology, Uludag University Medical School, Bursa, Turkey
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Gross E, Rothstein M, Dombek S, Juknis HI. Effect of spironolactone on blood pressure and the renin-angiotensin-aldosterone system in oligo-anuric hemodialysis patients. Am J Kidney Dis 2005; 46:94-101. [PMID: 15983962 DOI: 10.1053/j.ajkd.2005.03.005] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Through its actions on nonepithelial tissues, including brain, blood vessels, and heart, aldosterone may mediate hypertension, cardiac hypertrophy, and fibrosis. Whether aldosterone has a direct pathogenic role in the development of cardiovascular complications in patients with end-stage renal disease is unknown. Oligo-anuric dialysis patients provide a clinical setting to study the effects of the mineralocorticoid receptor blocker spironolactone that are independent of the diuretic properties of the drug. We performed a randomized, double-blinded, placebo-controlled, crossover study to assess the effect of spironolactone on blood pressure and the renin-angiotensin-aldosterone system in oligo-anuric hemodialysis patients. METHODS Eight hemodialysis patients were administered either spironolactone, 50 mg, or placebo orally twice daily for 2 weeks, followed by a 3-week washout period, after which patients crossed over in their treatment arms for 2 more weeks. RESULTS Administration of spironolactone for 2 weeks decreased predialysis systolic blood pressure from 142.0 +/- 19.6 to 131.4 +/- 18.2 mm Hg (P < 0.05). Compared with placebo, a 2-week course of spironolactone had no effect on predialysis and postdialysis plasma potassium or aldosterone concentrations or renin activity. CONCLUSION When administered for 2 weeks, spironolactone, 50 mg twice daily, reduced predialysis systolic blood pressure, but did not produce hyperkalemia in oligo-anuric hemodialysis patients.
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Affiliation(s)
- Evan Gross
- Department of Internal Medicine, Renal Division, Washington University School of Medicine, St Louis, MO, USA
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Cassis LA, Helton MJ, Howatt DA, King VL, Daugherty A. Aldosterone does not mediate angiotensin II-induced atherosclerosis and abdominal aortic aneurysms. Br J Pharmacol 2005; 144:443-8. [PMID: 15655500 PMCID: PMC1576022 DOI: 10.1038/sj.bjp.0706098] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
We have demonstrated previously that infusion of angiotensin II (AngII) into hyperlipidemic mice augments atherosclerosis and results in the formation of abdominal aortic aneurysms (AAA). The purpose of this study was to determine the role of aldosterone in these AngII-induced vascular pathologies. Male apolipoprotein E-/- (apoE) mice were infused with either vehicle or aldosterone (50 or 200 ng kg(-1) min(-1)). Arterial blood pressure was determined throughout the study and serum lipid concentrations and vascular pathology were quantified after 28 days of infusion. Infusion of aldosterone did not influence body weight or serum cholesterol concentrations. Kidney weight was increased dose-dependently by aldosterone infusion. Systolic blood pressure was not significantly altered by aldosterone. Plasma aldosterone concentrations were increased dose-dependently by infusion of aldosterone. However, there was no effect of aldosterone on the extent of atherosclerosis and AAAs were not formed. Implantation of pellets containing spironolactone (16 mg kg(-1) day(-1)) in AngII-infused apoE-/- mice (1000 ng kg(-1) min(-1)) had no effect on AngII-induced elevations in blood pressure. Plasma aldosterone concentration was not influenced by coadministration of spironolactone with AngII. Spironolactone administration did not influence the extent of atherosclerosis. Moreover, spironolactone had no significant effect on AngII-induced AAA (incidence of AAA formation: 80 versus 70% for vehicle versus spironolactone, respectively; not significant). These studies demonstrate that the AngII-induced vascular pathologies of atherosclerosis and AAA formation are not mediated through aldosterone.
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Affiliation(s)
- Lisa A Cassis
- Graduate Center for Nutritional Sciences, Charles T. Wethington Building, University of Kentucky, Lexington, KY 40536, U.S.A.
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Jaffe IZ, Mendelsohn ME. Angiotensin II and aldosterone regulate gene transcription via functional mineralocortocoid receptors in human coronary artery smooth muscle cells. Circ Res 2005; 96:643-50. [PMID: 15718497 DOI: 10.1161/01.res.0000159937.05502.d1] [Citation(s) in RCA: 273] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Inhibition or blockade of the angiotensin-aldosterone system consistently decreases ischemic cardiovascular events in clinical trials. The steroid hormone aldosterone acts by binding to the mineralocorticoid receptor (MR), a ligand activated transcription factor that is a member of the nuclear hormone receptor superfamily. MR binds and is activated by aldosterone and cortisol with equal affinity, but MR activation by cortisol is diminished in tissues that express the cortisol-inactivating enzyme 11-beta-hydroxysteroid-dehydrogenase-2 (11betaHSD2). Although previous studies support that the vasculature is a target tissue of aldosterone, MR-mediated gene expression in vascular cells has not been demonstrated or systematically explored. We investigated whether functional MR and 11betaHSD2 are expressed in human blood vessels. Human coronary and aortic vascular smooth muscle cells (VSMCs) express mRNA and protein for both MR and 11betaHSD2. The endogenous VSMC MR mediates aldosterone-dependent gene expression, which is blocked by the competitive MR antagonist spironolactone. Inhibition of 11betaHSD2 in coronary artery VSMCs enhances gene transactivation by cortisol, supporting that the VSMC 11betaHSD2 is functional. Angiotensin II also activates MR-mediated gene transcription in coronary artery VSMCs. Angiotensin II activation of MR-mediated gene expression is inhibited by both the AT1 receptor blocker losartan and by spironolactone, but not by aldosterone synthase inhibition. Microarray and quantitative RT-PCR experiments show that aldosterone activates expression of endogenous human coronary VSMC genes, including several involved in vascular fibrosis, inflammation, and calcification. These data support a new MR-dependent mechanism by which aldosterone and angiotensin II influence ischemic cardiovascular events, and suggest that ACE inhibitors and MR antagonists may decrease clinical ischemic events by inhibiting MR-dependent gene expression in vascular cells.
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MESH Headings
- 11-beta-Hydroxysteroid Dehydrogenase Type 2/biosynthesis
- 11-beta-Hydroxysteroid Dehydrogenase Type 2/genetics
- Adenoviridae/genetics
- Aldosterone/pharmacology
- Aldosterone/physiology
- Angiotensin II/pharmacology
- Angiotensin II/physiology
- Angiotensin II Type 1 Receptor Blockers/pharmacology
- Aorta/cytology
- Cell Line, Transformed/drug effects
- Cell Line, Transformed/metabolism
- Coronary Vessels/cytology
- Gene Expression Profiling
- Gene Expression Regulation/drug effects
- Gene Expression Regulation/physiology
- Genes, Reporter
- Genetic Vectors/genetics
- Humans
- Hydrocortisone/pharmacology
- Losartan/pharmacology
- Mammary Tumor Virus, Mouse/genetics
- Models, Biological
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Myocardial Ischemia/drug therapy
- Myocardial Ischemia/physiopathology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Oligonucleotide Array Sequence Analysis
- Promoter Regions, Genetic/drug effects
- Receptor, Angiotensin, Type 1/physiology
- Receptors, Mineralocorticoid/biosynthesis
- Receptors, Mineralocorticoid/drug effects
- Receptors, Mineralocorticoid/genetics
- Receptors, Mineralocorticoid/physiology
- Reverse Transcriptase Polymerase Chain Reaction
- Signal Transduction/physiology
- Spironolactone/pharmacology
- Transcription, Genetic/drug effects
- Transcription, Genetic/physiology
- Transduction, Genetic
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Affiliation(s)
- Iris Z Jaffe
- Molecular Cardiology Research Institute, Department of Medicine, New England Medical Center Hospitals and Tufts University School of Medicine, Boston, Mass 02111, USA
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Abstract
BACKGROUND The renin-angiotensin-aldosterone system (RAAS) contributes to hypertension and nephropathy. Until recently, aldosterone either has not been considered or has been considered a relatively minor component of the process-a contribution that could be negated with angiotensin-converting enzyme (ACE) inhibition or angiotensin receptor blockade. METHODS A Medline search was performed to identify relevant literature describing the role of aldosterone in the pathogenesis of renal dysfunction. RESULTS Growing evidence from experimental and clinical studies indicates that increased aldosterone is an independent contributor to small- and medium-sized arterial injury and nephropathy. Excess mineralocorticoid receptor stimulation of local and systemic origin promotes target organ dysfunction, vascular injury, and fibrosis, independent of the effects of other elements of the RAAS. Blockade of the RAAS with ACE inhibition or angiotensin receptor blockade often does not confer optimal protection from the effects of mineralocorticoids on small- and medium-sized blood vessels. Recent preliminary data from clinical studies indicate that aldosterone blockade protects the kidneys, sharply decreases proteinuria, beyond the activities of ACE inhibition or angiotensin receptor blockade and independent of beneficial blood pressure effects, and can protect patients from vascular injury associated with diabetes mellitus and hypertension. CONCLUSION Aldosterone blockade with the selective aldosterone blocker eplerenone, in combination with other RAAS inhibitors, is probably renoprotective and should be considered as a component of the treatment regimens of diabetic and hypertensive patients at risk for renal or cardiovascular disease expression. A high priority should be placed on developing the randomized, controlled trials required to establish that role.
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Affiliation(s)
- Norman K Hollenberg
- Department of Medicine and Department of Radiology, Brigham & Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
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Warnes KE, Coulter CL, Robinson JS, McMillen IC. The effect of intrafetal infusion of metyrapone on arterial blood pressure and on the arterial blood pressure response to angiotensin II in the sheep fetus during late gestation. J Physiol 2004; 552:621-33. [PMID: 14561842 PMCID: PMC2343390 DOI: 10.1113/jphysiol.2003.049437] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
While the impact of exogenous glucocorticoids on the fetal cardiovascular system has been well defined, relatively few studies have characterised the role of endogenous fetal glucocorticoids in the regulation of arterial blood pressure (BP) during late gestation. We have therefore infused metyrapone, an inhibitor of cortisol biosynthesis, into fetal sheep from 125 days gestation (when fetal cortisol concentrations are low) and from 137 days gestation (when fetal cortisol concentrations are increasing) and measured fetal plasma cortisol, 11-desoxycortisol and ACTH, fetal systolic, diastolic and mean arterial BP, heart rate, and the fetal BP responses to increasing doses of angiotensin II (AII). At 125 days gestation, there was a significant increase in fetal plasma ACTH and 11-desoxycortisol by 24 h after (+24 h) the start of the metyrapone infusion, and plasma cortisol concentrations were not different at +24 h when compared with pre-infusion values. Whilst the initial fall in circulating cortisol concentrations may have been transient, systolic, diastolic and mean arterial BP were ~5-6 mmHg lower (P < 0.05) in metyrapone- than in vehicle-infused fetuses at 24-48 h after the start of the infusion. When metyrapone was infused from 137/138 days gestation, there was a significant decrease in plasma cortisol concentrations by +6 h, which was followed by an increase back to pre-infusion values. While cortisol concentrations decreased, there was no change in fetal mean arterial BP during the first 24 h after the start of metyrapone infusion. Mean fetal arterial BP values at 137-139 days gestation were not different in fetuses that had been infused with either vehicle or metyrapone from 125 days gestation or with metyrapone from 137/138 days gestation. At 137-139 days gestation, however, arterial BP responses to increasing doses of AII were significantly blunted in fetuses that had been infused with metyrapone from 125 days gestation, when compared with fetuses that had been infused with metyrapone from 137/138 days gestation or with vehicle from 125 days gestation. The dissociation of the gestational age increase in arterial BP and the effects of intrafetal AII on fetal arterial BP indicates that increase in fetal BP with gestational age is not entirely a result of an increased vascular responsiveness to endogenous AII. Furthermore there may be a critical window during late gestation when the actions of cortisol contribute to the development of vascular responsiveness to AII.
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Affiliation(s)
- K E Warnes
- Departments of Physiology, University of Adelaide, Adelaide, Australia
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Bos R, Mougenot N, Médiani O, Vanhoutte PM, Lechat P. Potassium Canrenoate, an Aldosterone Receptor Antagonist, Reduces Isoprenaline-Induced Cardiac Fibrosis in the Rat. J Pharmacol Exp Ther 2004; 309:1160-6. [PMID: 14764658 DOI: 10.1124/jpet.103.063388] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The purpose of the present study was to determine whether the administration of an antagonist of aldosterone could prevent the fibrosis induced by an acute injection of isoprenaline. Male Wistar rats were submitted to one subcutaneous injection of isoprenaline (400 mg/kg) and were simultaneously treated with potassium canrenoate in drinking water (20 mg/kg/day) started 5 days before the injection of isoprenaline. Two months later, echocardiographic and hemodynamic measurements were performed. Then, the heart was prepared for morphometric histology and quantification of fibrosis in the left ventricle. Heart and left ventricular weights were increased significantly by isoprenaline. Potassium canrenoate attenuated this increase. The administration of isoprenaline increased significantly end diastolic diameter and end systolic volume compared with control. These changes were increased further with the addition of potassium canrenoate. In contrast, the fibrosis induced by isoprenaline was reduced significantly by potassium canrenoate at the three section levels. Potassium canrenoate attenuated the fibrosis but not the enhanced dilatation of the left ventricle induced by isoprenaline.
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Affiliation(s)
- Romain Bos
- Service de Pharmacologie, CHU Pitié Salpêtrière, 47 boulevard de l'Hôpital, 75651 Paris cedex 13, France
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Sheppard KE. Corticosteroid receptors, 11 beta-hydroxysteroid dehydrogenase, and the heart. VITAMINS AND HORMONES 2003; 66:77-112. [PMID: 12852253 DOI: 10.1016/s0083-6729(03)01003-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Mineralocorticoid and glucocorticoid hormones are known as corticosteroid hormones and are synthesized mainly in the adrenal cortex; however, more recently the enzymes involved in their synthesis have been found in a variety of cells and tissues, including the heart. The effects of these hormones are mediated via both cytoplasmic mineralocorticoid receptors (MRs) and glucocorticoid receptors (GRs), which act as ligand-inducible transcription factors. In addition, rapid, nongenomically mediated effects of these steroids can occur that may be via novel corticosteroid receptors. The lipophilic nature of these hormones allows them to pass freely through the cell membrane, although the intracellular concentration of mineralocorticoids and glucocorticoids is dependent on several cellular factors. The main regulators of intracellular glucocorticoid levels are 11 beta-hydroxysteroid dehydrogenase (11 beta HSD) isoforms. 11 beta HSD1 acts predominantly as a reductase in vivo, facilitating glucocorticoid action by converting circulating receptor-inactive 11-ketoglucocorticoids to active glucocorticoids. In contrast, 11 beta HSD 2 acts exclusively as an 11 beta-dehydrogenase and decreases intracellular glucocorticoids by converting them to their receptor-inactive 11-ketometabolites. Furthermore, P-glycoproteins, by actively pumping steroids out of cells, can selectively decrease steroids and local steroid synthesis can increase steroid concentrations. Receptor concentration, receptor modification, and receptor-protein interactions can also significantly impact on the corticosteroid response. This review details the receptors and possible mechanisms involved in both mediating and modulating corticosteroid responses. In addition, direct effects of corticosteroids on the heart are described including a discussion of the corticosteroid receptors and the mechanisms involved in mediating their effects.
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Affiliation(s)
- Karen E Sheppard
- Molecular Physiology Laboratory, Baker Heart Research Institute, Melbourne 8008, Victoria, Australia
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Ye P, Kenyon CJ, MacKenzie SM, Seckl JR, Fraser R, Connell JMC, Davies E. Regulation of aldosterone synthase gene expression in the rat adrenal gland and central nervous system by sodium and angiotensin II. Endocrinology 2003; 144:3321-8. [PMID: 12865309 DOI: 10.1210/en.2003-0109] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We have developed a highly sensitive QRT-PCR method for the measurement of CYP11B1 (11beta-hydroxylase) and CYP11B2 (aldosterone synthase) mRNAs to study their expression in the rat brain in response to dietary sodium manipulation and angiotensin (Ang)II infusion. Male Wistar Kyoto rats (n = 6) were fed normal, high, or low sodium diets for 12 d or were administered AngII or vehicle for 7 d. CYP11B2 and CYP11B1 expression was measured in RNA from adrenal gland and discrete brain regions using real-time QRT-PCR. Sodium restriction increased adrenal CYP11B2 expression 57-fold from 1.0 x 10(5) +/- 0.6 x 10(5) to 57 x 10(5) +/- 22 x 10(5) copies/ microg RNA (mean +/- SEM; P < 0.05);in the hippocampus, 14-fold from 5.4 x 10(2) +/- 0.8 x 10(2) to 74 x 10(2) +/- 31 x 10(2) copies/ microg RNA (P < 0.05); and in the cerebellum, 5-fold from 1.9 x 10(3) +/- 0.7 x 10(3) to 9.9 x 10(3) +/- 3.0 x 10(3) copies/ microg RNA (P < 0.01). CYP11B2 gene expression in the brainstem and hypothalamus was not affected. High-sodium diet reduced adrenal CYP11B2 expression to 0.19 x 10(5) +/- 0.1 x 10(5) copies/ microg RNA (P < 0.05) but did not affect central nervous system (CNS) expression significantly. AngII significantly increased adrenal CYP11B2 expression but did not affect CNS expression. Brain CYP11B1 mRNA levels were 10- to 1000-fold higher than CYP11B2 but were unaffected by dietary sodium or AngII. To summarize, we have identified a local CYP11B2 response to sodium depletion in the hippocampus and cerebellum. This is the first such regulation of CYP11B2 transcription to be identified in the CNS.
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Affiliation(s)
- Ping Ye
- Medical Research Council Blood Pressure Group, Western Infirmary, Glasgow, Scotland G11 6NT, United Kingdom
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Abstract
1. The major corticosteroids aldosterone and cortisol (corticosterone in rodents) are secreted from the adrenal cortex under the regulation of the renin-angiotensin system and the hypothalamic-pituitary-adrenal axis. 2. In addition to their accepted roles in such processes as blood pressure regulation, glycogenesis, hepatic glyconeogenesis and immunosuppression, the corticosteroids have been implicated in the development of cardiac fibrosis, modulation of hippocampal neuron excitability, memory formation and neurodegeneration. 3. The advent of sensitive molecular biological techniques has produced a wealth of evidence to support the existence of extra-adrenal corticosteroidogenic systems. Most attention has been paid to the cardiovascular system and the central nervous system, where the full array of enzymes required for the de novo synthesis of corticosteroids from cholesterol has been identified. 4. Although the evidence for local corticosteroid production is strong, the quantities of steroid would be small compared with adrenal production. Therefore, it is still a matter of debate as to whether extra-adrenal corticosteroids are of any physiological significance. This will depend on factors such as local concentration, proximity to target cells and, possibly, to tissue-specific control mechanisms.
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Affiliation(s)
- Eleanor Davies
- Blood Pressure Group, Division of Cardiovascular and Medical Sciences, Western Infirmary, Glasgow, UK
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MacKenzie SM, Fraser R, Connell JMC, Davies E. Local renin-angiotensin systems and their interactions with extra-adrenal corticosteroid production. J Renin Angiotensin Aldosterone Syst 2002; 3:214-21. [PMID: 12584665 DOI: 10.3317/jraas.2002.043] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Adrenal aldosterone production is regulated by the renin-angiotensin system (RAS). It is now known that several other tissues are capable of extra-adrenal aldosterone biosynthesis and that these tissues can also generate angiotensin II through local RAS. Therefore, the regulation of local aldosterone production by the local RAS is a distinct possibility. In this review, we present evidence for the existence of such systems in the vascular system, heart and brain. We then discuss the possibility of interactions between the RAS and aldosterone synthesis at the local level and speculate on the possible physiological effects of such systems in these tissues.
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Affiliation(s)
- Scott M MacKenzie
- Division of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, G116NT, Scotland.
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Xiu JC, Wu P, Xu JP, Guo Z, Lai W, Zhang Y, Li S, Li J, Liu Y. Effects of long-term enalapril and losartan therapy of heart failure on cardiovascular aldosterone. J Endocrinol Invest 2002; 25:463-8. [PMID: 12035945 DOI: 10.1007/bf03344039] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Plasma aldosterone escape is found during long-term ACE inhibitor therapy of chronic heart failure. Evidence for aldosterone production in cardiovascular tissues raised the question of whether aldosterone escape occurs or not in these tissues. Rats with infarction-induced chronic heart failure were treated with enalapril (20 mg/kg/d) and losartan (15 mg/kg/d) for 20 weeks. Untreated chronic heart failure and sham-operated rats were used as positive and normal controls, respectively. Ex vivo mesenteric artery and heart perfusion, high performance liquid chromatography, and RIA for aldosterone were performed. Chronic heart failure due to myocardial infarction was associated with tissue-specific activation of cardiovascular aldosterone synthesis. In the mesenteric artery, enalapril significantly inhibited aldosterone production compared to untreated, chronic heart failure rats, and losartan lowered aldosterone production to that of sham rats. In myocardium, enalapril failed to significantly inhibit aldosterone production, and losartan significantly inhibited aldosterone production compared to untreated, chronic heart failure rats. These results provide the first evidence that long-term ACE inhibition therapy induces aldosterone escape in myocardium but not in mesenteric artery of chronic heart failure. The angiotensin II subtype 1 receptor blocker losartan tranquilized aldosterone levels in the cardiovascular tissues of chronic heart failure rats.
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Affiliation(s)
- J C Xiu
- Department of Cardiology, Nan Fang Hospital, The First Military Medical University, Guangzhou, People's Republic of China
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Dorrance AM, Osborn HL, Grekin R, Webb RC. Spironolactone reduces cerebral infarct size and EGF-receptor mRNA in stroke-prone rats. Am J Physiol Regul Integr Comp Physiol 2001; 281:R944-50. [PMID: 11507012 DOI: 10.1152/ajpregu.2001.281.3.r944] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Remodeling of the cerebral vasculature contributes to the pathogenesis of cerebral ischemia. Remodeling is caused by increased smooth muscle proliferation and may be due to an increase in the responsiveness of vascular cells to epidermal growth factor (EGF). Aldosterone is a risk factor for stroke, and the literature suggests it may play a role in increasing the expression of the receptor for EGF (EGFR). We hypothesized that mRNA for the EGF-stimulated pathway would be elevated in the vasculature of stroke-prone spontaneously hypertensive rats (SHRSP) and that this and experimental ischemic cerebral infract size would be reduced by aldosterone inhibition with spironolactone. We found that spironolactone treatment reduced the size of cerebral infarcts after middle cerebral artery occlusion in SHRSP (51.69 +/- 3.60 vs. 22.00 +/- 6.69% of hemisphere-infarcted SHRSP vs. SHRSP + spironolactone P < 0.05). Expression of EGF and EGFR mRNA was higher in cerebral vessels and aorta from adult SHRSP compared with Wistar-Kyoto rats. Only the expression of EGFR mRNA was elevated in the young SHRSP. Spironolactone reduced the EGFR mRNA expression in the aorta (1.09 +/- 0.25 vs. 0.56 +/- 0.11 phosphorimage units SHRSP vs. SHRSP + spironolactone P < 0.05) but had no effect on EGF mRNA. In vitro incubation of aorta with aldosterone +/- spironolactone produced similar results, suggesting a direct effect of aldosterone. Thus spironolactone may reduce the size of cerebral infarcts via a reduction in the expression of the EGFR mRNA, leading to reduced remodeling.
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Affiliation(s)
- A M Dorrance
- Department of Physiology, University of Michigan, Ann Arbor, MI 48109, USA.
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48
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Ganguly A. Aldosterone. Compr Physiol 2000. [DOI: 10.1002/cphy.cp070305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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49
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Weber KT. Heart-hitting tales of salt and destruction. THE JOURNAL OF LABORATORY AND CLINICAL MEDICINE 2000; 136:7-13. [PMID: 10882222 DOI: 10.1067/mlc.2000.107301] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- K T Weber
- Department of Medicine, University of Tennessee Health Science Center, Memphis 38163, USA
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Abstract
Although the aldosterone escape mechanism is well known, aldosterone has often been neglected in the pathophysiologic consequences of the activated renin-angiotensin-aldosterone system in arterial hypertension and chronic heart failure. There is now evidence for vascular synthesis of aldosterone aside from its secretion by the adrenal cortex. Moreover, aldosterone is involved in vascular smooth muscle cell hypertrophy and hyperplasia, as well as in vascular matrix impairment and endothelial dysfunction. The mechanisms of action of aldosterone may be either delayed (genomic) or rapid (nongenomic). Deleterious effects of aldosterone leading to vascular target-organ damage include (besides salt and water retention) decreased arterial and venous compliance, increased peripheral vascular resistance, and impaired autonomic vascular control due to baroreflex dysfunction.
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Affiliation(s)
- D Duprez
- Department of Cardiology and Angiology, Ghent University Hospital, De Pintelaan 185, B-9000 Ghent, Belgium.
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