1
|
Cardiovascular Disease in Obstructive Sleep Apnea: Putative Contributions of Mineralocorticoid Receptors. Int J Mol Sci 2023; 24:ijms24032245. [PMID: 36768567 PMCID: PMC9916750 DOI: 10.3390/ijms24032245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/12/2023] [Accepted: 01/20/2023] [Indexed: 01/24/2023] Open
Abstract
Obstructive sleep apnea (OSA) is a chronic and highly prevalent condition that is associated with oxidative stress, inflammation, and fibrosis, leading to endothelial dysfunction, arterial stiffness, and vascular insulin resistance, resulting in increased cardiovascular disease and overall mortality rates. To date, OSA remains vastly underdiagnosed and undertreated, with conventional treatments yielding relatively discouraging results for improving cardiovascular outcomes in OSA patients. As such, a better mechanistic understanding of OSA-associated cardiovascular disease (CVD) and the development of novel adjuvant therapeutic targets are critically needed. It is well-established that inappropriate mineralocorticoid receptor (MR) activation in cardiovascular tissues plays a causal role in a multitude of CVD states. Clinical studies and experimental models of OSA lead to increased secretion of the MR ligand aldosterone and excessive MR activation. Furthermore, MR activation has been associated with worsened OSA prognosis. Despite these documented relationships, there have been no studies exploring the causal involvement of MR signaling in OSA-associated CVD. Further, scarce clinical studies have exclusively assessed the beneficial role of MR antagonists for the treatment of systemic hypertension commonly associated with OSA. Here, we provide a comprehensive overview of overlapping mechanistic pathways recruited in the context of MR activation- and OSA-induced CVD and propose MR-targeted therapy as a potential avenue to abrogate the deleterious cardiovascular consequences of OSA.
Collapse
|
2
|
Ishikawa T, Morimoto S, Ichihara A. Effects of mineralocorticoid receptor antagonists on sex hormones and body composition in patients with primary aldosteronism. Hypertens Res 2021; 45:496-506. [PMID: 34961793 DOI: 10.1038/s41440-021-00836-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 11/17/2021] [Accepted: 12/04/2021] [Indexed: 11/10/2022]
Abstract
Mineralocorticoid receptor antagonists are frequently used for the treatment of primary aldosteronism. Steroidal mineralocorticoid receptor antagonists may have antagonistic actions on androgen receptors, agonistic actions on progesterone receptors, and antagonistic actions on mineralocorticoid receptors. Because anti-androgen effects may cause body fat accumulation and skeletal muscle atrophy, there are concerns that this drug may have adverse effects on body composition. Therefore, in this randomized prospective study, we compared the adverse effects of spironolactone, a steroidal mineralocorticoid receptor antagonist, and esaxerenone, a nonsteroidal mineralocorticoid receptor antagonist, on sex hormone levels and body composition in patients with primary aldosteronism without severe renal dysfunction. The serum concentration of free testosterone was significantly higher in the spironolactone group than in the esaxerenone group in both males and females. However, the levels of estradiol, progesterone, luteinizing hormone, and follicle stimulating hormone did not significantly increase. Changes in body fat percentage and muscle mass rate were not significantly different between the two groups. No patient showed a serum potassium level ≥6.0 mEq/L; however, serum potassium levels were significantly higher in the spironolactone group than in the esaxerenone group. These data indicate that spironolactone may have antagonistic effects on androgen receptors. Esaxerenone did not show any apparent adverse effects, suggesting that it can be safely used in patients with primary aldosteronism.
Collapse
Affiliation(s)
- Toru Ishikawa
- Department of Endocrinology and Hypertension, Tokyo Women's Medical University, Tokyo, Japan
| | - Satoshi Morimoto
- Department of Endocrinology and Hypertension, Tokyo Women's Medical University, Tokyo, Japan.
| | - Atsuhiro Ichihara
- Department of Endocrinology and Hypertension, Tokyo Women's Medical University, Tokyo, Japan
| |
Collapse
|
3
|
Neumann J, Boknik P, Kirchhefer U, Gergs U. The role of PP5 and PP2C in cardiac health and disease. Cell Signal 2021; 85:110035. [PMID: 33964402 DOI: 10.1016/j.cellsig.2021.110035] [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: 01/05/2021] [Revised: 04/16/2021] [Accepted: 05/03/2021] [Indexed: 02/08/2023]
Abstract
Protein phosphatases are important, for example, as functional antagonists of β-adrenergic stimulation of the mammalian heart. While β-adrenergic stimulations increase the phosphorylation state of regulatory proteins and therefore force of contraction in the heart, these phosphorylations are reversed and thus force is reduced by the activity of protein phosphatases. In this context the role of PP5 and PP2C is starting to unravel. They do not belong to the same family of phosphatases with regard to sequence homology, many similarities with regard to location, activation by lipids and putative substrates have been worked out over the years. We also suggest which pathways for regulation of PP5 and/or PP2C described in other tissues and not yet in the heart might be useful to look for in cardiac tissue. Both phosphatases might play a role in signal transduction of sarcolemmal receptors in the heart. Expression of PP5 and PP2C can be increased by extracellular stimuli in the heart. Because PP5 is overexpressed in failing animal and human hearts, and because overexpression of PP5 or PP2C leads to cardiac hypertrophy and KO of PP5 leads to cardiac hypotrophy, one might argue for a role of PP5 and PP2C in heart failure. Because PP5 and PP2C can reduce, at least in vitro, the phosphorylation state of proteins thought to be relevant for cardiac arrhythmias, a role of these phosphatases for cardiac arrhythmias is also probable. Thus, PP5 and PP2C might be druggable targets to treat important cardiac diseases like heart failure, cardiac hypertrophy and cardiac arrhythmias.
Collapse
Affiliation(s)
- Joachim Neumann
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Magdeburger Str. 4, D-06097 Halle, Germany.
| | - Peter Boknik
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Westfälische Wilhelms-Universität, Domagkstraße 12, D-48149 Münster, Germany.
| | - Uwe Kirchhefer
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Westfälische Wilhelms-Universität, Domagkstraße 12, D-48149 Münster, Germany.
| | - Ulrich Gergs
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Magdeburger Str. 4, D-06097 Halle, Germany.
| |
Collapse
|
4
|
Piaditis GP, Kaltsas G, Markou A, Chrousos GP. Five Reasons for the Failure to Diagnose Aldosterone Excess in Hypertension. Horm Metab Res 2020; 52:827-833. [PMID: 32882712 DOI: 10.1055/a-1236-4869] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Primary hyperaldosteronism (PA) is a well-known cause of hypertension although its exact prevalence amongst patients with apparent essential hypertension has been a matter of debate. A number of recent studies have suggested that mild forms of PA may be relatively common taking into consideration factors that were previously either overestimated or ignored when developing diagnostic tests of PA and when applying these tests into normotensive individuals. The performance characteristics and diagnostic accuracy of such tests are substantially increased when the adrenocorticotrophin effect, inappropriate potassium levels and their application in carefully selected normotensive individuals are considered. In the present review, we critically analyze these issues and provide evidence that several, particularly mild, forms of PA can be effectively identified exhibiting potentially important clinical implications.
Collapse
Affiliation(s)
- George P Piaditis
- Department of Endocrinology and Diabetes Center, "G. Gennimatas" General Hospital, Athens, Greece
| | - Gregory Kaltsas
- Department of Pathophysiology, National University of Athens, Athens, Greece
| | - Athina Markou
- Department of Endocrinology and Diabetes Center, "G. Gennimatas" General Hospital, Athens, Greece
| | - George P Chrousos
- University Research Institute of Maternal and Child Health and Precision Medicine, National and Kapodistrian University of Athens, Medical School, Athens, Greece
| |
Collapse
|
5
|
Chikina AS, Nadalin F, Maurin M, San-Roman M, Thomas-Bonafos T, Li XV, Lameiras S, Baulande S, Henri S, Malissen B, Lacerda Mariano L, Barbazan J, Blander JM, Iliev ID, Matic Vignjevic D, Lennon-Duménil AM. Macrophages Maintain Epithelium Integrity by Limiting Fungal Product Absorption. Cell 2020; 183:411-428.e16. [PMID: 32970988 PMCID: PMC7646275 DOI: 10.1016/j.cell.2020.08.048] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 07/27/2020] [Accepted: 08/26/2020] [Indexed: 12/14/2022]
Abstract
The colon is primarily responsible for absorbing fluids. It contains a large number of microorganisms including fungi, which are enriched in its distal segment. The colonic mucosa must therefore tightly regulate fluid influx to control absorption of fungal metabolites, which can be toxic to epithelial cells and lead to barrier dysfunction. How this is achieved remains unknown. Here, we describe a mechanism by which the innate immune system allows rapid quality check of absorbed fluids to avoid intoxication of colonocytes. This mechanism relies on a population of distal colon macrophages that are equipped with "balloon-like" protrusions (BLPs) inserted in the epithelium, which sample absorbed fluids. In the absence of macrophages or BLPs, epithelial cells keep absorbing fluids containing fungal products, leading to their death and subsequent loss of epithelial barrier integrity. These results reveal an unexpected and essential role of macrophages in the maintenance of colon-microbiota interactions in homeostasis. VIDEO ABSTRACT.
Collapse
Affiliation(s)
- Aleksandra S Chikina
- Institut Curie, PSL Research University, CNRS UMR 144, F-75005 Paris, France; Institut Curie, PSL Research University, INSERM U932, F-75005 Paris, France
| | - Francesca Nadalin
- Institut Curie, PSL Research University, INSERM U932, F-75005 Paris, France
| | - Mathieu Maurin
- Institut Curie, PSL Research University, INSERM U932, F-75005 Paris, France
| | - Mabel San-Roman
- Institut Curie, PSL Research University, INSERM U932, F-75005 Paris, France
| | | | - Xin V Li
- Gastroenterology and Hepatology Division, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY 10021, USA; The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY 10021, USA
| | - Sonia Lameiras
- Institut Curie, PSL Research University, Next Generation Sequencing Facility, F-75005 Paris, France
| | - Sylvain Baulande
- Institut Curie, PSL Research University, Next Generation Sequencing Facility, F-75005 Paris, France
| | - Sandrine Henri
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, INSERM, CNRS, 13288 Marseille, France
| | - Bernard Malissen
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, INSERM, CNRS, 13288 Marseille, France; Centre d'Immunophénomique, Aix Marseille Université, INSERM, CNRS, 13288 Marseille, France
| | | | - Jorge Barbazan
- Institut Curie, PSL Research University, CNRS UMR 144, F-75005 Paris, France
| | - J Magarian Blander
- The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY 10021, USA
| | - Iliyan D Iliev
- Gastroenterology and Hepatology Division, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY 10021, USA; The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY 10021, USA
| | | | | |
Collapse
|
6
|
Young MJ, Adler GK. Aldosterone, the Mineralocorticoid Receptor and Mechanisms of Cardiovascular Disease. VITAMINS AND HORMONES 2019; 109:361-385. [DOI: 10.1016/bs.vh.2018.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
7
|
Ong GSY, Young MJ. Mineralocorticoid regulation of cell function: the role of rapid signalling and gene transcription pathways. J Mol Endocrinol 2017; 58:R33-R57. [PMID: 27821439 DOI: 10.1530/jme-15-0318] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 11/06/2016] [Indexed: 12/22/2022]
Abstract
The mineralocorticoid receptor (MR) and mineralocorticoids regulate epithelial handling of electrolytes, and induces diverse effects on other tissues. Traditionally, the effects of MR were ascribed to ligand-receptor binding and activation of gene transcription. However, the MR also utilises a number of intracellular signalling cascades, often by transactivating unrelated receptors, to change cell function more rapidly. Although aldosterone is the physiological mineralocorticoid, it is not the sole ligand for MR. Tissue-selective and mineralocorticoid-specific effects are conferred through the enzyme 11β-hydroxysteroid dehydrogenase 2, cellular redox status and properties of the MR itself. Furthermore, not all aldosterone effects are mediated via MR, with implication of the involvement of other membrane-bound receptors such as GPER. This review will describe the ligands, receptors and intracellular mechanisms available for mineralocorticoid hormone and receptor signalling and illustrate their complex interactions in physiology and disease.
Collapse
Affiliation(s)
- Gregory S Y Ong
- Cardiovascular Endocrinology LaboratoryCentre for Endocrinology and Metabolism, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of MedicineSchool of Clinical Sciences, Monash University, Clayton, Victoria, Australia
| | - Morag J Young
- Cardiovascular Endocrinology LaboratoryCentre for Endocrinology and Metabolism, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of PhysiologySchool of Biomedical Sciences, Monash University, Clayton, Victoria, Australia
| |
Collapse
|
8
|
Pojoga LH, Yao TM, Opsasnick LA, Siddiqui WT, Reslan OM, Adler GK, Williams GH, Khalil RA. Cooperative Role of Mineralocorticoid Receptor and Caveolin-1 in Regulating the Vascular Response to Low Nitric Oxide-High Angiotensin II-Induced Cardiovascular Injury. J Pharmacol Exp Ther 2015; 355:32-47. [PMID: 26183312 DOI: 10.1124/jpet.115.226043] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 07/14/2015] [Indexed: 12/22/2022] Open
Abstract
Aldosterone interacts with mineralocorticoid receptor (MR) to stimulate sodium reabsorption in renal tubules and may also affect the vasculature. Caveolin-1 (cav-1), an anchoring protein in plasmalemmal caveolae, binds steroid receptors and also endothelial nitric oxide synthase, thus limiting its translocation and activation. To test for potential MR/cav-1 interaction in the vasculature, we investigated if MR blockade in cav-1-replete or -deficient states would alter vascular function in a mouse model of low nitric oxide (NO)-high angiotensin II (AngII)-induced cardiovascular injury. Wild-type (WT) and cav-1 knockout mice (cav-1(-/-)) consuming a high salt diet (4% NaCl) received Nω-nitro-l-arginine methyl ester (L-NAME) (0.1-0.2 mg/ml in drinking water at days 1-11) plus AngII (0.7-2.8 mg/kg per day via an osmotic minipump at days 8-11) ± MR antagonist eplerenone (EPL) 100 mg/kg per day in food. In both genotypes, blood pressure increased with L-NAME + AngII. EPL minimally changed blood pressure, although its dose was sufficient to block MR and reverse cardiac expression of the injury markers cluster of differentiation 68 and plasminogen activator inhibitor-1 in L-NAME+AngII treated mice. In aortic rings, phenylephrine and KCl contraction was enhanced with EPL in L-NAME+AngII treated WT mice, but not cav-1(-/-) mice. AngII-induced contraction was not different, and angiotensin type 1 receptor expression was reduced in L-NAME + AngII treated WT and cav-1(-/-) mice. In WT mice, acetylcholine-induced relaxation was enhanced with L-NAME + AngII treatment and reversed with EPL. Acetylcholine relaxation in cav-1(-/-) mice was greater than in WT mice, not modified by L-NAME + AngII or EPL, and blocked by ex vivo L-NAME, 1H-(1,2,4)oxadiazolo(4,3-a)quinoxalin-1-one (ODQ), or endothelium removal, suggesting the role of NO-cGMP. Cardiac endothelial NO synthase was increased in cav-1(-/-) versus WT mice, further increased with L-NAME + AngII, and not affected by EPL. Vascular relaxation to the NO donor sodium nitroprusside was increased with L-NAME + AngII in WT mice but not in cav-1(-/-) mice. Plasma aldosterone levels increased and cardiac MR expression decreased in L-NAME + AngII treated WT and cav-1(-/-) mice and did not change with EPL. Thus, during L-NAME + AngII induced hypertension, MR blockade increases contraction and alters vascular relaxation via NO-cGMP, and these changes are absent in cav-1 deficiency states. The data suggest a cooperative role of MR and cav-1 in regulating vascular contraction and NO-cGMP-mediated relaxation during low NO-high AngII-dependent cardiovascular injury.
Collapse
Affiliation(s)
- Luminita H Pojoga
- Cardiovascular Endocrinology Section, Endocrinology, Diabetes, and Hypertension Division (L.H.P., T.M.Y., G.K.A., G.H.W.), and Division of Vascular and Endovascular Surgery (L.A.O., W.T.S., O.M.R., R.A.K.), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Tham M Yao
- Cardiovascular Endocrinology Section, Endocrinology, Diabetes, and Hypertension Division (L.H.P., T.M.Y., G.K.A., G.H.W.), and Division of Vascular and Endovascular Surgery (L.A.O., W.T.S., O.M.R., R.A.K.), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Lauren A Opsasnick
- Cardiovascular Endocrinology Section, Endocrinology, Diabetes, and Hypertension Division (L.H.P., T.M.Y., G.K.A., G.H.W.), and Division of Vascular and Endovascular Surgery (L.A.O., W.T.S., O.M.R., R.A.K.), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Waleed T Siddiqui
- Cardiovascular Endocrinology Section, Endocrinology, Diabetes, and Hypertension Division (L.H.P., T.M.Y., G.K.A., G.H.W.), and Division of Vascular and Endovascular Surgery (L.A.O., W.T.S., O.M.R., R.A.K.), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Ossama M Reslan
- Cardiovascular Endocrinology Section, Endocrinology, Diabetes, and Hypertension Division (L.H.P., T.M.Y., G.K.A., G.H.W.), and Division of Vascular and Endovascular Surgery (L.A.O., W.T.S., O.M.R., R.A.K.), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Gail K Adler
- Cardiovascular Endocrinology Section, Endocrinology, Diabetes, and Hypertension Division (L.H.P., T.M.Y., G.K.A., G.H.W.), and Division of Vascular and Endovascular Surgery (L.A.O., W.T.S., O.M.R., R.A.K.), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Gordon H Williams
- Cardiovascular Endocrinology Section, Endocrinology, Diabetes, and Hypertension Division (L.H.P., T.M.Y., G.K.A., G.H.W.), and Division of Vascular and Endovascular Surgery (L.A.O., W.T.S., O.M.R., R.A.K.), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Raouf A Khalil
- Cardiovascular Endocrinology Section, Endocrinology, Diabetes, and Hypertension Division (L.H.P., T.M.Y., G.K.A., G.H.W.), and Division of Vascular and Endovascular Surgery (L.A.O., W.T.S., O.M.R., R.A.K.), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| |
Collapse
|
9
|
Lother A, Moser M, Bode C, Feldman RD, Hein L. Mineralocorticoids in the heart and vasculature: new insights for old hormones. Annu Rev Pharmacol Toxicol 2014; 55:289-312. [PMID: 25251996 DOI: 10.1146/annurev-pharmtox-010814-124302] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The mineralocorticoid aldosterone is a key regulator of water and electrolyte homeostasis. Numerous recent developments have advanced the field of mineralocorticoid pharmacology—namely, clinical trials have shown the beneficial effects of aldosterone antagonists in chronic heart failure and post-myocardial infarction treatment. Experimental studies using cell type-specific gene targeting of the mineralocorticoid receptor (MR) gene in mice have revealed the importance of extrarenal aldosterone signaling in cardiac myocytes, endothelial cells, vascular smooth cells, and macrophages. In addition, several molecular pathways involving signal transduction via the classical MR as well as the G protein-coupled receptor GPER mediate the diverse spectrum of effects of aldosterone on cells. This knowledge has initiated the development of new pharmacological ligands to specifically interfere with targets on different levels of aldosterone signaling. For example, aldosterone synthase inhibitors such as LCI699 and the novel nonsteroidal MR antagonist BAY 94-8862 have been tested in clinical trials. Interference with the interaction between MR and its coregulators seems to be a promising strategy toward the development of selective MR modulators.
Collapse
Affiliation(s)
- Achim Lother
- Heart Center, Department of Cardiology and Angiology I, University of Freiburg, 79106 Freiburg, Germany;
| | | | | | | | | |
Collapse
|
10
|
Rickard AJ, Morgan J, Bienvenu LA, Fletcher EK, Cranston GA, Shen JZ, Reichelt ME, Delbridge LM, Young MJ. Cardiomyocyte mineralocorticoid receptors are essential for deoxycorticosterone/salt-mediated inflammation and cardiac fibrosis. Hypertension 2012; 60:1443-50. [PMID: 23108646 DOI: 10.1161/hypertensionaha.112.203158] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Because the role of mineralocorticoid receptors in specific cell types in cardiac remodeling remains unknown, we have compared cardiac responses with deoxycorticosterone/salt in cardiomyocyte mineralocorticoid receptor-null (MyoMRKO) and wild-type (WT) mice at 8 days and 8 weeks. No differences in cardiac function between untreated WT and MyoMRKO mice were found, whereas profibrotic markers were reduced in MyoMRKO hearts at baseline. At 8 days, MyoMRKO showed monocyte/macrophage recruitment equivalent to WT mice in response to deoxycorticosterone/salt but a suppression of markers of fibrosis compared with WT. At 8 weeks, MyoMRKO mice showed no deoxycorticosterone/salt-induced increase in inflammatory cell infiltration and collagen deposition or in proinflammatory gene expression. Although some profibrotic markers were equivalently increased in both genotypes, MyoMRKO mice also showed increased baseline levels of mRNA and protein for the transforming growth factor-β/connective tissue growth factor inhibitor decorin compared with WT that was accompanied by higher levels of matrix metalloproteinase 2/matrix metalloproteinase 9 activity. These data point to a direct role for cardiomyocyte mineralocorticoid receptor in both deoxycorticosterone/salt-induced tissue inflammation and remodeling and suggest potential mechanisms for the cardioprotective effects of selective mineralocorticoid receptor blockade in cardiomyocytes that may involve regulation of matrix metalloproteinase 2/matrix metalloproteinase 9 activity and the transforming growth factor-β-connective tissue growth factor profibrotic pathway.
Collapse
Affiliation(s)
- Amanda J Rickard
- Prince Henry’s Institute of Medical Research, Clayton, Victoria, Australia
| | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Die JV, Román B. RNA quality assessment: a view from plant qPCR studies. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:6069-77. [PMID: 23045609 DOI: 10.1093/jxb/ers276] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) is probably the most common molecular technique used in transcriptome analyses today. The simplicity of the technology and associated protocols that generate results without the need to understand the underlying principles has made RT-qPCR the method of choice for RNA quantification. Rather than the 'gold standard technology' often used to describe it, the performance of RT-qPCR suffers from considerable pitfalls during general workflow. The inconsistency of conventional methods for the evaluation of RNA quality and its influence on qPCR performance as well as stability of reference genes is summarized and discussed here.
Collapse
Affiliation(s)
- Jose V Die
- Mejora Genética Vegetal, Instituto de Agricultura Sostenible, CSIC, 14080 Córdoba, Spain.
| | | |
Collapse
|
12
|
Young MJ, Rickard AJ. Mechanisms of mineralocorticoid salt-induced hypertension and cardiac fibrosis. Mol Cell Endocrinol 2012; 350:248-55. [PMID: 21930186 DOI: 10.1016/j.mce.2011.09.008] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Revised: 09/01/2011] [Accepted: 09/04/2011] [Indexed: 02/06/2023]
Abstract
For 50 years aldosterone has been thought to act primarily on epithelia to regulate fluid and electrolyte homeostasis. Mineralocorticoid receptors (MR), however, are also expressed in nonepithelial tissues such as the heart and vascular smooth muscle. Recently pathophysiologic effects of nonepithelial MR activation by aldosterone have been demonstrated, in the context of inappropriate mineralocorticoid for salt status, including coronary vascular inflammation and cardiac fibrosis. Consistent with experimental studies, clinical trials (RALES, EPHESUS), have demonstrated a reduced mortality and morbidity when MR antagonists are included in the treatment of moderate-severe heart failure. The pathogenesis of MR-mediated cardiovascular disease is a complex, multifactorial process that involves loss of vascular reactivity, hypertension, inflammation of the vasculature and end organs (heart and kidney), oxidative stress and tissue fibrosis (cardiac and renal). This review will discuss the mechanisms by which MR, located in the various cell types that comprise the heart, plays a central role in the development of cardiomyocyte failure, tissue inflammation, remodelling and hypertension.
Collapse
Affiliation(s)
- Morag J Young
- Prince Henry's Institute of Medical Research, Department of Physiology, Monash University, Clayton, VIC 3168, Australia.
| | | |
Collapse
|
13
|
Odermatt A, Kratschmar DV. Tissue-specific modulation of mineralocorticoid receptor function by 11β-hydroxysteroid dehydrogenases: an overview. Mol Cell Endocrinol 2012; 350:168-86. [PMID: 21820034 DOI: 10.1016/j.mce.2011.07.020] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 07/03/2011] [Accepted: 07/09/2011] [Indexed: 01/23/2023]
Abstract
In the last decade significant progress has been made in the understanding of mineralocorticoid receptor (MR) function and its implications for physiology and disease. The knowledge on the essential role of MR in the regulation of electrolyte concentrations and blood pressure has been significantly extended, and the relevance of excessive MR activation in promoting inflammation, fibrosis and heart disease as well as its role in modulating neuronal cell viability and brain function is now widely recognized. Despite considerable progress, the mechanisms of MR function in various cell-types are still poorly understood. Key modulators of MR function include the glucocorticoid receptor (GR), which may affect MR function by formation of heterodimers and by differential genomic and non-genomic responses on gene expression, and 11β-hydroxysteroid dehydrogenases (11β-HSDs), which determine the availability of intracellular concentrations of active glucocorticoids. In this review we attempted to provide an overview of the knowledge on MR expression with regard to the presence or absence of GR, 11β-HSD2 and 11β-HSD1/hexose-6-phosphate dehydrogenase (H6PDH) in various tissues and cell types. The consequences of cell-specific differences in the coexpression of MR with these proteins need to be further investigated in order to understand the role of this receptor in a given tissue as well as its systemic impact.
Collapse
Affiliation(s)
- Alex Odermatt
- Division of Molecular and Systems Toxicology, Department of Pharmaceutical Sciences, University of Basel, Klingelbergstrasse 50, Basel, Switzerland.
| | | |
Collapse
|
14
|
Pojoga LH, Coutinho P, Rivera A, Yao TM, Maldonado ER, Youte R, Adler GK, Williams J, Turchin A, Williams GH, Romero JR. Activation of the mineralocorticoid receptor increases striatin levels. Am J Hypertens 2012; 25:243-9. [PMID: 22089104 DOI: 10.1038/ajh.2011.197] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Aldosterone (ALDO), a critical regulator of sodium homeostasis, mediates its effects via activation of the mineralocorticoid receptor (MR) through mechanisms that are not entirely clear. Striatin, a membrane associated protein, interacts with estrogen receptors in endothelial cells. METHODS We studied the effects of MR activation in vitro and in vivo on striatin levels in vascular tissue. RESULTS We observed that dietary sodium restriction was associated with increased striatin levels in mouse heart and aorta and that striatin and MR are present in the human endothelial cell line, (EA.hy926), and in mouse aortic endothelial cells (MAEC). Further, we show that MR co-precipitates with striatin in vascular tissue. Incubation of EA.hy926 cells with ALDO (10(-8) mol/l for 5-24 h) increases striatin protein and mRNA expression, an effect that was inhibited by canrenoic acid, an MR antagonist. Consistent with these observations, incubation of MAEC with ALDO increased striatin levels that were likewise blocked by canrenoic acid. To test the in vivo relevance of these findings, we studied two previously described mouse models of increased ALDO levels. Intraperitoneal ALDO administration augmented the abundance of striatin protein in mouse heart. We also observed that in a murine model of chronic ALDO-mediated cardiovascular damage following treatment with N(G)-nitro-L-arginine methyl ester plus angiotensin II an increased abundance of striatin protein in heart and kidney tissue. CONCLUSION Our results provide evidence that increased striatin levels is a component of MR activation in the vasculature and suggest that regulation of striatin by ALDO may modulate estrogen's nongenomic effects.
Collapse
|
15
|
Pojoga LH, Williams JS, Yao TM, Kumar A, Raffetto JD, do Nascimento GRA, Reslan OM, Adler GK, Williams GH, Shi Y, Khalil RA. Histone demethylase LSD1 deficiency during high-salt diet is associated with enhanced vascular contraction, altered NO-cGMP relaxation pathway, and hypertension. Am J Physiol Heart Circ Physiol 2011; 301:H1862-71. [PMID: 21873498 DOI: 10.1152/ajpheart.00513.2011] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Histone methylation, a determinant of chromatin structure and gene transcription, was thought to be irreversible, but recent evidence suggests that lysine-specific demethylase-1 (LSD1, Kdm1a) induces demethylation of histone H3 lysine 4 (H3K4) or H3K9 and thereby alters gene transcription. We previously demonstrated a human LSD1 phenotype associated with salt-sensitive hypertension. To test the hypothesis that LSD1 plays a role in the regulation of blood pressure (BP) via vascular mechanisms and gene transcription, we measured BP and examined vascular function and endothelial nitric oxide (NO) synthase (eNOS) expression in thoracic aorta of male wild-type (WT) and heterozygous LSD1 knockout mice (LSD1(+/-)) fed either a liberal salt (HS; 4% NaCl) or restricted salt diet (LS; 0.08% NaCl). BP was higher in LSD1(+/-) than WT mice on the HS diet but not different between LSD1(+/-) and WT mice on the LS diet. Further examination of the mechanisms of this salt-sensitive hypertension in LSD1(+/-) mice on the HS diet demonstrated that plasma renin activity and plasma levels and urinary excretion of aldosterone were less in LSD1(+/-) than WT, suggesting suppressed renin-angiotensin-aldosterone system. In contrast, phenylephrine (Phe)-induced aortic contraction was greater in LSD1(+/-) than WT mice on the HS diet. Treatment of aortic rings with 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ; a blocker of guanylate cyclase) enhanced Phe contraction in LSD1(+/-) compared with WT mice on the HS diet. Acetylcholine (Ach)-induced relaxation was less in LSD1(+/-) than WT mice on the HS diet. Endothelium removal or pretreatment with N(ω)-nitro-L-arginine methyl ester (blocker of NOS) or ODQ abolished Ach-induced relaxation in aorta of WT but had minimal effect in LSD1(+/-). Vascular relaxation to sodium nitroprusside, an exogenous NO donor and guanylate cyclase activator, was decreased in LSD1(+/-) vs. WT mice on the HS diet. RT-PCR and Western blots revealed decreased eNOS mRNA expression and eNOS and guanylate cyclase protein in the heart and aorta of LSD1(+/-) compared with WT mice on HS diet. Thus, during the HS diet, LSD1 deficiency is associated with hypertension, enhanced vascular contraction, and reduced relaxation via NO-cGMP pathway. The data support a role for LSD1-mediated histone demethylation in the regulation of NOS/guanylate cyclase gene expression, vascular function, and BP during the HS diet.
Collapse
Affiliation(s)
- Luminita H Pojoga
- Cardiovascular Endocrine Section, Division of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA 02115, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Newfell BG, Iyer LK, Mohammad NN, McGraw AP, Ehsan A, Rosano G, Huang PL, Mendelsohn ME, Jaffe IZ. Aldosterone regulates vascular gene transcription via oxidative stress-dependent and -independent pathways. Arterioscler Thromb Vasc Biol 2011; 31:1871-80. [PMID: 21617142 DOI: 10.1161/atvbaha.111.229070] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE Aldosterone (Aldo) antagonism prevents cardiovascular mortality by unclear mechanisms. Aldo binds to the mineralocorticoid receptor (MR), a ligand-activated transcription factor, which is expressed in human vascular cells. Here we define the early Aldo-regulated vascular transcriptome and investigate the mechanisms of gene regulation by Aldo in the vasculature that may contribute to vascular disease. METHODS AND RESULTS Gene expression profiling of Aldo-treated mouse aortas identified 72 genes regulated by Aldo. These genes are overrepresented in Gene Ontology categories involved in vascular function and disease. Quantitative reverse transcription-polymerase chain reaction was used to confirm and further explore mechanisms of vascular gene regulation by Aldo. Aldo-regulated vascular gene expression was inhibited by actinomycin D and MR antagonists supporting a transcriptional MR-dependent mechanism. Aldo regulation of a subset of genes was enhanced in the setting of vascular endothelial denudation and blocked by the free radical scavenger Tempol, supporting synergy between Aldo and vascular injury that is oxidative stress dependent. In the aortic arch, a region predisposed to atherosclerosis, the injury-enhanced genes also demonstrated enhanced expression compared with the descending aorta, both at baseline and after Aldo exposure. Furthermore, the clinically beneficial MR antagonist spironolactone inhibited expression of the identified genes in aortic tissue from humans with atherosclerosis. CONCLUSIONS This study defines the Aldo-regulated vascular transcriptome and characterizes a subset of proatherogenic genes with enhanced Aldo-stimulated, oxidative stress-dependent expression in the setting of vascular injury and in areas predisposed to atherosclerosis. Inhibition of MR regulation of these genes may play a role in the protective effects of Aldo antagonists in patients with vascular disease, and these pathways may provide novel drug targets to prevent atherosclerosis in humans.
Collapse
Affiliation(s)
- Brenna G Newfell
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA 02111, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Yu H, Tu K, Xie L, Li YY. DigOut: viewing differential expression genes as outliers. J Bioinform Comput Biol 2010; 8 Suppl 1:161-75. [PMID: 21155026 DOI: 10.1142/s0219720010005208] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Revised: 08/25/2010] [Accepted: 09/10/2010] [Indexed: 01/03/2023]
Abstract
With regards to well-replicated two-conditional microarray datasets, the selection of differentially expressed (DE) genes is a well-studied computational topic, but for multi-conditional microarray datasets with limited or no replication, the same task is not properly addressed by previous studies. This paper adopts multivariate outlier analysis to analyze replication-lacking multi-conditional microarray datasets, finding that it performs significantly better than the widely used limit fold change (LFC) model in a simulated comparative experiment. Compared with the LFC model, the multivariate outlier analysis also demonstrates improved stability against sample variations in a series of manipulated real expression datasets. The reanalysis of a real non-replicated multi-conditional expression dataset series leads to satisfactory results. In conclusion, a multivariate outlier analysis algorithm, like DigOut, is particularly useful for selecting DE genes from non-replicated multi-conditional gene expression dataset.
Collapse
Affiliation(s)
- Hui Yu
- Bioinformatics Center, Key Laboratory of Systems Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, P R China.
| | | | | | | |
Collapse
|
18
|
Latouche C, Sainte-Marie Y, Steenman M, Castro Chaves P, Naray-Fejes-Toth A, Fejes-Toth G, Farman N, Jaisser F. Molecular signature of mineralocorticoid receptor signaling in cardiomyocytes: from cultured cells to mouse heart. Endocrinology 2010; 151:4467-76. [PMID: 20591974 PMCID: PMC2940498 DOI: 10.1210/en.2010-0237] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Excess mineralocorticoid signaling is deleterious for cardiovascular functions, as demonstrated by the beneficial effects of mineralocorticoid receptor (MR) antagonism on morbidity and mortality in patients with heart failure. However, the understanding of signaling pathways after MR activation in the heart remains limited. We performed transcriptomic analyses in the heart of double-transgenic mice with conditional, cardiomyocyte-specific, overexpression of the MR (MRcardio mice) or the glucocorticoid receptor (GR; GRcardio mice). Some of the genes induced in MRcardio mice were selected for comparative evaluation (real time PCR) in vivo in the heart of mice and ex vivo in the MR-expressing cardiomyocyte H9C2 cell line after aldosterone or corticosterone treatment. We demonstrate that chronic MR overexpression in the heart results in a limited number of induced (n = 24) and repressed (n = 22) genes compared with their control littermates. These genes are specifically modulated by MR because there is limited overlap (three induced, four repressed) with the genes that are regulated in the heart of GRcardio mice (compared with control mice: 70 induced, 73 repressed). Interestingly, some MR-induced genes that are up-regulated in vivo in mice are also induced by 24-h aldosterone treatment in H9C2 cells, such as plasminogen activator inhibitor 1 and Serpina-3 (alpha1-antichymotrypsin). The signaling pathways that are affected by long-term activation of MR may be of particular interest to design novel therapeutic targets in cardiac diseases.
Collapse
Affiliation(s)
- Celine Latouche
- Institut National de la Santé et de la Recherche Médicale Unité Mixte de Recherche 872 Team 1, Centre de Recherches des Cordeliers, Université Pierre et Marie Curie, 15 Rue de l'Ecole de Médecine, 75006 Paris, France
| | | | | | | | | | | | | | | |
Collapse
|
19
|
Pojoga LH, Adamová Z, Kumar A, Stennett AK, Romero JR, Adler GK, Williams GH, Khalil RA. Sensitivity of NOS-dependent vascular relaxation pathway to mineralocorticoid receptor blockade in caveolin-1-deficient mice. Am J Physiol Heart Circ Physiol 2010; 298:H1776-88. [PMID: 20363891 DOI: 10.1152/ajpheart.00661.2009] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Endothelial caveolin-1 (cav-1) is an anchoring protein in plasma membrane caveolae where it binds endothelial nitric oxide synthase (eNOS) and limits its activation, particularly in animals fed a high salt (HS) diet. Cav-1 also interacts with steroid receptors such as the mineralocorticoid receptor (MR). To test the hypothesis that vascular reactivity is influenced by an interplay between MR and cav-1 during HS diet, we examined the effects of MR blockade on NOS-mediated vascular relaxation in normal and cav-1-deficient mice. Wild-type (WT) and cav-1 knockout mice (cav-1(-/-)) were fed for 14 days a HS (4% NaCl) diet with and without the MR antagonist eplerenone (Epl; 100 mg x kg(-1) x day(-1)). After systolic blood pressure (BP) was measured, the thoracic aorta was isolated for measurement of vascular reactivity, and the aorta and heart were used for measurement of eNOS and MR expression. BP was not different between WT + Epl and WT, but was higher in cav-1(-/-) + Epl than in cav-1(-/-) mice. Phenylephrine (Phe)-induced vascular contraction was less in cav-1(-/-) than WT, and significantly enhanced in cav-1(-/-) + Epl than in cav-1(-/-), but not in WT + Epl compared with WT. Endothelium removal and NOS blockade by N(omega)-nitro-l-arginine methyl ester (l-NAME) enhanced Phe contraction in cav-1(-/-), but not cav-1(-/-) + Epl. ACh-induced aortic relaxation was reduced in cav-1(-/-) + Epl versus cav-1(-/-), but not in WT + Epl compared with WT. Endothelium removal, l-NAME, and the guanylate cyclase inhibitor ODQ abolished the large ACh-induced relaxation in cav-1(-/-) and the remaining relaxation in the cav-1(-/-) + Epl but had similar inhibitory effect in WT and WT + Epl. Real-time RT-PCR indicated decreased eNOS mRNA expression in the aorta and heart, and Western blots revealed decreased total eNOS in the heart of cav-1(-/-) + Epl compared with cav-1(-/-). Vascular and cardiac MR expression was less in cav-1(-/-) than WT, but not in cav-1(-/-) + Epl compared with cav-1(-/-). Plasma aldosterone (Aldo) was not different between WT and cav-1(-/-) mice nontreated or treated with Epl. Thus in cav-1 deficiency states and HS diet MR blockade is associated with increased BP, enhanced vasoconstriction, and decreased NOS-mediated vascular relaxation and eNOS expression. The data suggest that, in the absence of cav-1, MR activation plays a beneficial role in regulating eNOS expression/activity and, consequently, the vascular function during HS diet.
Collapse
Affiliation(s)
- Luminita H Pojoga
- Cardiovascular Endocrine Section, Endocrinology, Diabetes and Hypertension Division, Harvard Medical School, Boston, MA, USA
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Odermatt A, Atanasov AG. Mineralocorticoid receptors: emerging complexity and functional diversity. Steroids 2009; 74:163-71. [PMID: 19022273 DOI: 10.1016/j.steroids.2008.10.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2008] [Revised: 10/18/2008] [Accepted: 10/20/2008] [Indexed: 12/29/2022]
Abstract
Mineralocorticoid receptor (MR) activation in renal epithelial cells in response to the binding of aldosterone has long been implicated in the maintenance of body salt and fluid homeostasis and blood pressure control. 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) is believed to confer specificity on aldosterone to activate MR by inactivating 11beta-hydroxyglucocorticoids (corticosterone, cortisol) that are 100-1000 times more abundant in plasma than aldosterone and that can also bind and activate MR. Increasing evidence, however, challenges such a simple view of MR activation as well as its interaction with glucocorticoids and 11beta-HSDs. In non-epithelial tissues including brain, cardiomyocytes and macrophages, 11beta-hydroxyglucocorticoids seem to act as MR antagonists, and redox changes and signaling events may play pivotal roles for receptor activation in these tissues. This review addresses the emerging new view of the complex mechanisms underlying MR specificity of action, with a diversity of physiological roles and functions in different mineralocorticoid-responsive tissues.
Collapse
Affiliation(s)
- Alex Odermatt
- Division of Molecular and Systems Toxicology, Department of Pharmaceutical Sciences, University of Basel, Klingelbergstrasse 50, CH-4056 Basel, Switzerland.
| | | |
Collapse
|
21
|
Ricchiuti V, Lian CG, Oestreicher EM, Tran L, Stone JR, Yao T, Seely EW, Williams GH, Adler GK. Estradiol increases angiotensin II type 1 receptor in hearts of ovariectomized rats. J Endocrinol 2009; 200:75-84. [PMID: 18931023 PMCID: PMC2927364 DOI: 10.1677/joe-08-0199] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We tested the hypothesis that 17beta-estradiol (E(2)) has dual effects on the heart, increasing levels of proteins thought to have beneficial cardiovascular effects (e.g. endothelial nitric oxide (NO) synthase (eNOS)) as well as those thought to have detrimental cardiovascular effects (e.g. type 1 angiotensin II (AngII) receptor (AT(1)R)). Ovariectomized Wistar rats consuming a high-sodium diet received one of four treatments (n=7 per group): group 1, placebo pellets; group 2, E(2) (0 x 5 mg/pellet, 21-day release); group 3, NOS inhibitor, N(omega)-nitro-L-arginine-methyl-ester (L-NAME; 40 mg/kg per day for 14 days) plus Ang II (0 x 225 mg/kg per day on days 11-14); group 4, E(2) plus L-NAME/Ang II. E(2) increased cardiac levels of estrogen receptors ESR1 and ESR2, an ESR-associated membrane protein caveolin-3, eNOS, and phosphorylated (p)eNOS, thus, exerting potentially beneficial cardiovascular effects on NO. However, E(2) also increased cardiac levels of proteins associated with cardiovascular injury and inflammation including, AT(1)R, protein kinase C delta (PRKCD), phosphorylated PRKC, and phosphorylated extracellular signal regulated kinase (pMAPK)3/1, plasminogen activator inhibitor-1 (PAI-1), osteopontin and ED-1, a monocyte/macrophage-specific protein. E(2) treatment led to similar protein changes in the hearts of L-NAME/Ang II-treated rats except that the increase in peNOS was prevented, and L-NAME/Ang II and E(2) had additive effects in increasing cardiac PRKCD and PAI-1. Thus, the highest levels of cardiac PAI-1 and PRKCD occurred in L-NAME/Ang II-treated rats receiving E(2). In summary, E(2) treatment increased cardiac expression of AT(1)R as well as the expression of pro-inflammatory and prothrombotic factors.
Collapse
Affiliation(s)
- Vincent Ricchiuti
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Hayashi H, Kobara M, Abe M, Tanaka N, Gouda E, Toba H, Yamada H, Tatsumi T, Nakata T, Matsubara H. Aldosterone nongenomically produces NADPH oxidase-dependent reactive oxygen species and induces myocyte apoptosis. Hypertens Res 2008; 31:363-75. [PMID: 18360057 DOI: 10.1291/hypres.31.363] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The roles of aldosterone in the progression of heart failure have not been fully elucidated. This study examined whether aldosterone nongenomically activates reactive oxygen species (ROS) production, causing myocyte apoptosis. Addition of aldosterone to neonatal rat cardiac myocytes caused the activation of NADPH oxidase and intracellular ROS production in a dose-dependent manner (10-(9)-10(-7) mol/L). NADPH oxidase activation was evident as soon as 5 min after aldosterone treatment. Neither an inhibitor for nuclear transcription (actinomycin D) nor an inhibitor of new protein synthesis (cycloheximide) blocked this rapid activation, and specific binding of aldosterone to plasma membrane fraction was inhibited by eplerenone, suggesting a nongenomic mechanism. Aldosterone did not affect the mRNA or protein levels of NOX2, which is a major subunit of NADPH oxidase in myocytes, after 48 h. Nuclear staining with DAPI showed that aldosterone (10(-7) mol/L) increased the myocyte apoptosis (2.3 fold, p<0.001), coincident with the activation of caspase-3 (1.4 fold, p<0.05), compared with the serum-deprived control after 48 h. Aldosterone also induced phosphorylation of apoptosis signal-regulating kinase 1 (ASK1). These effects of aldosterone on myocyte ROS accumulation, ASK1 activation, and apoptosis were abolished by eplerenone, a mineralocorticoid receptor (MR) antagonist, apocynin, an inhibitor of NADPH oxidase activation, and tempol, a free radical scavenger, but by neither RU486, a glucocorticoid receptor antagonist, nor butylated hydroxyanisol (BHA), a mitochondrial ROS scavenger. In conclusion, aldosterone-mediated ROS production is blocked by eplerenone and induced by the nongenomic activation of NADPH oxidase, leading to myocyte apoptosis associated with ASK1 activation. These proapoptotic actions of aldosterone may play a role in the progression of heart failure.
Collapse
Affiliation(s)
- Hironori Hayashi
- Department of Cardiovascular Medicine, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Mechanisms of mineralocorticoid receptor-mediated cardiac fibrosis and vascular inflammation. Curr Opin Nephrol Hypertens 2008; 17:174-80. [DOI: 10.1097/mnh.0b013e3282f56854] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
24
|
Pojoga LH, Yao TM, Sinha S, Ross RL, Lin JC, Raffetto JD, Adler GK, Williams GH, Khalil RA. Effect of dietary sodium on vasoconstriction and eNOS-mediated vascular relaxation in caveolin-1-deficient mice. Am J Physiol Heart Circ Physiol 2008; 294:H1258-65. [PMID: 18178722 DOI: 10.1152/ajpheart.01014.2007] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Changes in dietary sodium intake are associated with changes in vascular volume and reactivity that may be mediated, in part, by alterations in endothelial nitric oxide synthase (eNOS) activity. Caveolin-1 (Cav-1), a transmembrane anchoring protein in the plasma membrane caveolae, binds eNOS and limits its translocation and activation. To test the hypothesis that endothelial Cav-1 participates in the dietary sodium-mediated effects on vascular function, we assessed vascular responses and nitric oxide (NO)-mediated mechanisms of vascular relaxation in Cav-1 knockout mice (Cav-1-/-) and wild-type control mice (WT; Cav-1+/+) placed on a high-salt (HS; 4% NaCl) or low-salt (LS; 0.08% NaCl) diet for 16 days. After the systolic blood pressure was measured, the thoracic aorta was isolated for measurement of vascular reactivity and NO production, and the heart was used for measurement of eNOS expression and/or activity. The blood pressure was elevated in HS mice treated with NG-nitro-l-arginine methyl ester and more so in Cav-1-/- than WT mice and was significantly reduced during the LS diet. Phenylephrine caused vascular contraction that was significantly reduced in Cav-1-/- (maximum 0.25 +/- 0.06 g/mg) compared with WT (0.75 +/- 0.22 g/mg) on the HS diet, and the differences were eliminated with the LS diet. Also, vascular contraction in response to membrane depolarization by high KCl (96 mM) was reduced in Cav-1-/- (0.27 +/- 0.05 g/mg) compared with WT mice (0.53 +/- 0.12 g/mg) on the HS diet, suggesting that the reduced vascular contraction is not limited to a particular receptor. Acetylcholine (10(-5) M) caused aortic relaxation in WT mice on HS (23.6 +/- 3.5%) and LS (23.7 +/- 5.5%) that was enhanced in Cav-1-/- HS (72.6 +/- 6.1%) and more so in Cav-1-/- LS mice (93.6 +/- 3.5%). RT-PCR analysis indicated increased eNOS mRNA expression in the aorta and heart, and Western blots indicated increased total eNOS and phosphorylated eNOS in the heart of Cav-1-/- compared with WT mice on the HS diet, and the genotypic differences were less apparent during the LS diet. Thus Cav-1 deficiency during the HS diet is associated with decreased vasoconstriction, increased vascular relaxation, and increased eNOS expression and activity, and these effects are altered during the LS diet. The data support the hypothesis that endothelial Cav-1, likely through an effect on eNOS activity, plays a prominent role in the regulation of vascular function during substantial changes in dietary sodium intake.
Collapse
Affiliation(s)
- Luminita H Pojoga
- Cardiovascular Endocrine Section, Endocrinology, Diabetes and Hypertension Division, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Hinds TD, Sánchez ER. Protein phosphatase 5. Int J Biochem Cell Biol 2007; 40:2358-62. [PMID: 17951098 DOI: 10.1016/j.biocel.2007.08.010] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2007] [Revised: 08/21/2007] [Accepted: 08/21/2007] [Indexed: 01/16/2023]
Abstract
Protein phosphatase 5 (PP5) is a unique member of the PPP family of serine/threonine phosphatases based on the presence of tetratricopeptide repeat (TPR) domains within its structure. Since its discovery, PP5 has been implicated in wide ranging cellular processes, including MAPK-mediated growth and differentiation, cell cycle arrest and DNA damage repair via the p53 and ATM/ATR pathways, regulation of ion channels via the membrane receptor for atrial natriuretic peptide, the cellular heat shock response as mediated by heat shock transcription factor, and steroid receptor signaling, especially glucocorticoid receptor (GR). Given this diversity of effects, the recent development of viable PP5-deficient mice was surprising and suggests that PP5 is a modulatory, rather than essential, factor in phosphorylation pathways. Here, we review the signaling involvement of PP5 in light of new findings and relate these activities to the structural features of the protein.
Collapse
Affiliation(s)
- Terry D Hinds
- Department of Physiology & Pharmacology, University of Toledo College of Medicine, 3035 Arlington Avenue, Toledo, OH 43614-5804, USA.
| | | |
Collapse
|
26
|
Bibliography. Current world literature. Adrenal cortex. Curr Opin Endocrinol Diabetes Obes 2007; 14:255-9. [PMID: 17940448 DOI: 10.1097/med.0b013e3281de7489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|