Brain renin–angiotensin–aldosterone system and ventricular remodeling after myocardial infarct: a reviewThis article is one of a selection of papers published in a special issue on Advances in Cardiovascular Research.

2009 ◽  
Vol 87 (12) ◽  
pp. 979-988 ◽  
Author(s):  
Katherine V. Westcott ◽  
Bing S. Huang ◽  
Frans H.H. Leenen

After a myocardial infarct (MI), a variety of mechanisms contribute to progressive cardiac remodeling and dysfunction. Progressive activation of central sympathoexcitatory pathways appears to depend on a neuromodulatory pathway, involving local production of aldosterone and release of endogenous ouabain-like compounds (‘ouabain’) possibly from magnocellular neurons in the supraoptic and paraventricular nuclei. ‘Ouabain’ may lower the membrane potential of neurons and thereby enhance activity of angiotensinergic pathways. These central pathways appear to coordinate progressive activation of several peripheral mechanisms such as sympathetic tone and circulating and cardiac renin–angiotensin–aldosterone system (RAAS). Central blockade of aldosterone production, mineralocorticoid receptors, ‘ouabain’ activity, or AT1 receptors similarly prevents activation of these peripheral mechanisms. Cardiac remodeling after MI involves progressive left ventricular dilation, fibrosis, and decrease in contractile performance. Central blockade of this neuromodulatory pathway causes a marked attenuation of the remodeling and dysfunction, presumably by inhibiting increases in (cardiac) sympathetic activity and RAAS. At the cellular level, these systems may contribute to the cardiac remodeling by activating proinflammatory cytokines and cardiac myocyte apoptosis. New therapeutic approaches, specifically preventing activation of this brain neuromodulatory pathway, may lead to more optimal and specific approaches to the prevention of heart failure after MI.

2004 ◽  
Vol 287 (3) ◽  
pp. H1303-H1311 ◽  
Author(s):  
David Engel ◽  
Ronald Peshock ◽  
Robert C. Armstong ◽  
Natarajan Sivasubramanian ◽  
Douglas L. Mann

Although cardiac myocyte apoptosis has been detected in explanted hearts from patients with end-stage dilated and ischemic cardiomyopathy, the relative contribution of apoptotic cell death to left ventricular (LV) remodeling and cardiac decompensation is not known. To determine whether progressive cardiac myocyte apoptosis contributes to the transition from a hypertrophic to a dilated cardiac phenotype that is observed in transgenic myosin heavy chain secreted TNF (MHCsTNF) mice with cardiac restricted overexpression of tumor necrosis factor (TNF), we assessed cardiac myocyte apoptosis (using a DNA ligase technique) in MHCsTNF mice and littermate control mice in relation to serial changes in LV structure, which was assessed using MRI. The prevalence of cardiac myocyte apoptosis increased progressively from 4 to 12 wk as the hearts of the MHCsTNF mice underwent the transition from a concentric hypertrophic to a dilated cardiac phenotype. Treatment of the MHCsTNF mice with the broad-based caspase inhibitor N-[(1,3-dimethylindole-2-carbonyl)-valinyl]-3-amino4-oxo-5-fluoropentanoic acid significantly decreased cardiac myocyte apoptosis and significantly attenuated LV wall thinning and adverse cardiac remodeling. Additional studies suggested that the TNF-induced decrease in Bcl-2 expression and activation of the intrinsic mitochondrial death pathway were responsible for the cardiac myocyte apoptosis observed in the MHCsTNF mice. These studies show that progressive cardiac myocyte apoptosis is sufficient to contribute to adverse cardiac remodeling in the adult mammalian heart through progressive LV wall thinning.


2012 ◽  
Vol 32 (1) ◽  
pp. 33-41 ◽  
Author(s):  
Avshesh Mishra ◽  
Anshika Srivastava ◽  
T. Mittal ◽  
N. Garg ◽  
B. Mittal

Background: Left ventricular dysfunction (LVD), followed by fall in cardiac output is one of the major complications in some coronary artery disease (CAD) patients. The decreased cardiac output over time leads to activation of the renin-angiotensin-aldosterone system which results in vasoconstriction by influencing salt-water homeostasis. Therefore, the purpose of the present study was to explore the association of single nucleotide polymorphisms (SNPs) in angiotensin I converting enzyme;ACE(rs4340), angiotensin II type1 receptor; AT1 (rs5186) and aldosterone synthase;CYP11B2(rs1799998) with LVD.Methods and results: The present study was carried out in two cohorts. The primary cohort included 308 consecutive patients with angiographically confirmed CAD and 234 healthy controls. Among CAD, 94 with compromised left ventricle ejection fraction (LVEF ≤ 45) were categorized as LVD. The ACE I/D, AT1 A1166C andCYP11B2T-344C polymorphisms were determined by PCR. Our results showed that ACE I/D was significantly associated with CAD but not with LVD. However, AT1 1166C variant was significantly associated with LVD (LVEF ≤ 45) (p value=0.013; OR=3.69), butCYP11B2(rs1799998) was not associated with either CAD or LVD. To validate our results, we performed a replication study in additional 200 cases with similar clinical characteristics and results again confirmed consistent findings (p value=0.020; OR=5.20).Conclusion: AT1 A1166C plays important role in conferring susceptibility of LVD.


Biomolecules ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1771
Author(s):  
Alex Cleber Improta-Caria ◽  
Marcela Gordilho Aras ◽  
Luca Nascimento ◽  
Ricardo Augusto Leoni De Sousa ◽  
Roque Aras-Júnior ◽  
...  

MicroRNAs are small non-coding RNAs that regulate gene and protein expression. MicroRNAs also regulate several cellular processes such as proliferation, differentiation, cell cycle, apoptosis, among others. In this context, they play important roles in the human body and in the pathogenesis of diseases such as cancer, diabetes, obesity and hypertension. In hypertension, microRNAs act on the renin–angiotensin–aldosterone system, sympathetic nervous system and left ventricular hypertrophy, however the signaling pathways that interact in these processes and are regulated by microRNAs inducing hypertension and the worsening of the disease still need to be elucidated. Thus, the aim of this review is to analyze the pattern of expression of microRNAs in these processes and the possible associated signaling pathways.


2013 ◽  
Vol 28 (4) ◽  
pp. 336-347 ◽  
Author(s):  
Daniela Vivenza ◽  
Mauro Feola ◽  
Ornella Garrone ◽  
Martino Monteverde ◽  
Marco Merlano ◽  
...  

Background Anthracyclines are among the most active drugs against breast cancer, but can exert cardiotoxic effects eventually resulting in congestive heart failure (CHF). Identifying breast cancer patients at high risk of developing cardiotoxicity after anthracycline therapy would be of value in guiding the use of these agents. Aims We determined whether polymorphisms in the renin-angiotensin-aldosterone system (RAAS) and in the glutathione S-transferase (GST) family of phase II detoxification enzymes might be useful predictors of left ventricular ejection fraction (LVEF) kinetics and risk of developing CHF. We sought correlations between the development of cardiotoxicity and gene polymorphisms in 48 patients with early breast cancer treated with adjuvant anthracycline chemotherapy. Methods We analyzed the following polymorphisms: p.Met235Thr and p.Thr174Met in angiotensinogen ( AGT), Ins/Del in angiotensin-converting enzyme ( ACE), A1166C in angiotensin II type-1 receptor ( AGTR1A), c.-344T>C in aldosterone synthase ( CYP11B2), p.Ile105Val in GSTP1. Additionally, we analyzed the presence or absence of the GSTT1 and GSTP1 genes. A LVEF <50% was detected at least once during the 3 years of follow-up period in 13 out of 48 patients (27.1%). Conclusion RAAS gene polymorphisms were not significantly associated with the development of cardiotoxicity. GSTM1 may be useful as a biomarker of higher risk of cardiotoxicity, as demonstrated in our cohort of patients (p=0.147).


2020 ◽  
Vol 15 (9) ◽  
pp. 1-9
Author(s):  
Kate O'Donovan

Heart failure with reduced ejection fraction is associated with decreased functional capacity, poor quality of life and increased mortality risk. The neurohormonal compensatory response to a reduced cardiac output is mainly comprised of the sympathetic nervous system, natriuretic peptides and the renin–angiotensin–aldosterone system, which attempt to maintain peripheral perfusion. The renin–angiotensin–aldosterone system is an integral mechanism in increasing afterload by promoting angiotensin II-mediated vasoconstriction and increasing preload via the secretion of aldosterone which causes sodium and water retention. Albeit compensatory mechanisms attempt to increase cardiac output and perfusion, their effects are maladaptive as left ventricular function deteriorates in response to an increased afterload, preload and ventricular remodelling. In an attempt to interrupt this vicious circle, first-line pharmacological therapy in the treatment of heart failure is beta blockade and inhibition of the renin–angiotensin–aldosterone system. Integral to this treatment strategy are mineralocorticoid receptor antagonists, also known as aldosterone antagonists. This class of drug inhibits the action of aldosterone, decreases preload and reduces left ventricular workload, thus preserving ventricular function. This translates into reduced mortality incidence, decreased episodes of hospitalisations for cardiac causes and improvement in clinical signs and symptoms. Although patient benefits are explicit, adverse effects such as hyperkalaemia and renal impairment are associated with this therapy. Regular patient follow up and monitoring for potential adverse effects and drug interactions are essential to the success of the therapy.


2010 ◽  
Vol 55 (25) ◽  
pp. 2869-2876 ◽  
Author(s):  
Katrina Go Yamazaki ◽  
Pam R. Taub ◽  
Maraliz Barraza-Hidalgo ◽  
Maria M. Rivas ◽  
Alexander C. Zambon ◽  
...  

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