Bloqueo del eje renina angiontensina aldosterona (RAAS) en la enfermedad renal diabética. Más allá del control de la hipertensión arterial / Renin angiotensin aldosterone system (RAAS) and its suppression in diabetic kidney disease. Control of arterial hypertension and beyond

La enfermedad renal diabética (ERD) es una comorbilidad con alta prevalencia a nivel mundial, siendo una de las complicaciones más frecuentes de la diabetes mellitus (DM). La ERD se relaciona con complicaciones cardiovasculares y progresión de la enfermedad renal crónica (ERC), por ello la identificación de factores modificables, como el control de la presión arterial, es uno de los pilares más importantes en el manejo integral. En esta revisión hacemos un recorrido sobre el papel de la hipertensión y el bloqueo del eje renina angiotensina aldosterona (RAAS) en el curso de la ERD y las estrategias terapéuticas orientadas a la reducción de la presión arterial (PA), el bloqueo RAAS y el impacto en resultados renales y cardiovasculares. El objetivo de este artículo es hacer una revisión de las intervenciones más importantes que actúan bloqueando el eje renina angiotensina aldosterona (RAAS) y determinar si estas medidas en los pacientes con ERD, solo tienen impacto en el control de la presión arterial o si también son estrategias de nefro y cardio-protección. Conclusión: La ERD es una de las complicaciones más frecuentes de la diabetes mellitus (DM). El control de la PA sigue siendo un pilar fundamental para lograr estos objetivos. Los bloqueadores del RAAS (iECAS y BRAs) son los antihipertensivos de elección con efecto terapéutico por el bloqueo RAAS y esto les permite tener además del control de la PA, efectos nefroprotectores y cardioprotectores importantes en pacientes con ERD, sobre todo cuando hay la presencia de albuminuria. Evaluamos que además de los inhibidores de la enzima convertidora de angiotensina (iECAs) y los bloqueadores del receptor de angiotensina (BRAs), vienen tomando importancia los antagonistas selectivos del receptor mineralocorticoide (ARM) como Finerenona.

Diabetic kidney disease (DKD) is a comorbidity with a high worldwide prevalence, and one of the most frequent complications of diabetes mellitus (DM). CKD is related to cardiovascular complications and the progression of chronic kidney disease (CKD), therefore the identification of modifiable factors, such as blood pressure control, is one of the most important pillars in comprehensive management. In this review, we will analyze the role of hypertension and the renin-angiotensin-aldosterone system (RAAS) and its suppression in the course of CKD, and therapeutic strategies aimed at reducing blood pressure (BP), RAAS blockade, and the impact on renal and cardiovascular outcomes. The objective of this article is to review the most important interventions that act by blocking the renin-angiotensin-aldosterone system (RAAS) and to determine if these measures in patients with CKD only have an impact on blood pressure control or if they are also nephron and cardio-protective strategies. Conclusion: DKD is one of the most frequent complications of diabetes mellitus (DM). BP control continues to be a fundamental pillar to achieve these objectives. RAAS blockers (iECAS and ARBs) are the first-line antihypertensive with a therapeutic effect due to RAAS blockade and this allows them to have, in addition to BP control, important nephroprotective and cardioprotective effects in patients with CKD, especially when there is albuminuria. We evaluated that in addition to angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), selective mineralocorticoid receptor antagonists (MRA) such as Finerenone are gaining importance.

Determination of perindopril erbumine by oxidative coupling reaction using 2, 6-dichloroquinone-4-chlorimide

Abstract Perindopril erbumine (Perindopril tert-butylamine salt) is a potent angiotensin-converting enzyme (ACE) inhibitor. It is used to treat the patients with hypertension and heart failure problems. A sensitive, inexpensive and precise analytical technique has been developed for the estimation of perindopril in bulk and formulations. The procedure involves the development of colour by forming an oxidative coupling reaction between drug (PPE) and reagent such as 2, 6-dichloroquinone-4-chlorimide (DCQC). The formed colored species were measured at (max=520 nm. The developed method showed linearity within the concentration limits of 25-75 µg mL-1. The linear correlation coefficient (r) and molar absorptivity were found to be 0.9999 and 3.285 x 103 mol-1cm-1. % Recovery ± SD values were in the range of 99.69 - 100.51 (+ 0.42 - ( 0.41) (n=3) which indicates the accuracy of the developed method. The interference of other excipients that are commonly present in formulations is found to be negligible. Precision and accuracy of the proposed method were confirmed by student t-test and F-tests at 95% confidence limits with (n-1) degrees of freedom. The validity parameters of proposed method were calculated by ICH guidelines

Local renin angiotensin system and sperm DNA fragmentation / 亚洲男科学杂志(英文版)

The renin angiotensin system (RAS) appears to influence male fertility at multiple levels. In this work, we analyzed the relationship between the RAS and DNA integrity. Fifty male volunteers were divided into two groups (25 each): control (DNA fragmentation ≤20%) and pathological (DNA fragmentation >20%) cases. Activities of five peptidases controlling RAS were measured fluorometrically: prolyl endopeptidase (which converts angiotensin [A] I and A II to A 1-7), neutral endopeptidase (NEP/CD10: A I to A 1-7), aminopeptidase N (APN/CD13: A III to A IV), aminopeptidase A (A II to A III) and aminopeptidase B (A III to A IV). Angiotensin-converting enzyme (A I to A II), APN/CD13 and NEP/CD10 were also assessed by semiquantitative cytometry and quantitative flow cytometry assays, as were the receptors of all RAS components: A II receptor type 1 (AT1R), A II receptor type 2 (AT2R), A IV receptor (AT4R or insulin-regulated aminopeptidase [IRAP]), (pro)renin receptor (PRR) and A 1-7 receptor or Mas receptor (MasR) None of the enzymes that regulate levels of RAS components, except for APN/CD13 (decrease in fragmented cells), showed significant differences between both groups. Micrographs of RAS receptors revealed no significant differences in immunolabeling patterns between normozoospermic and fragmented cells. Labeling of AT1R (94.3% normozoospermic vs 84.1% fragmented), AT4R (96.2% vs 95.3%) and MasR (97.4% vs 87.2%) was similar between the groups. AT2R (87.4% normozoospermic vs 63.1% fragmented) and PRR (96.4% vs 48.2%) were higher in non-fragmented spermatozoa. These findings suggest that fragmented DNA spermatozoa have a lower capacity to respond to bioactive RAS peptides.

Levels of angiotensin-converting enzyme 1 and 2 in serum and urine of children with Sickle Cell Disease / Níveis de enzima conversora da angiotensina 1 e 2 no soro e na urina de crianças com Doença Falciforme

Abstract Introduction: Sickle cell nephropathy begins in childhood and presents early increases in glomerular filtration, which, over the long term, can lead to chronic renal failure. Several diseases have increased circulating and urinary angiotensin-converting enzyme (ACE) activity, but there is little information about changes in ACEs activity in children with sickle cell disease (SCD). Objective: We examined circulating and urinary ACE 1 activity in children with SCD. Methods: This cross-sectional study compared children who were carriers of SCD with children who comprised a control group (CG). Serum and urinary activities of ACE were evaluated, as were biochemical factors, urinary album/creatinine rates, and estimated glomerular filtration rate. Results: Urinary ACE activity was significantly higher in patients with SCD than in healthy children (median 0.01; range 0.00-0.07 vs median 0.00; range 0.00-0.01 mU/mL·creatinine, p < 0.001. No significant difference in serum ACE activities between the SCD and CG groups was observed (median 32.25; range 16.2-59.3 vs median 40.9; range 18.0-53.4) mU/m`L·creatinine, p < 0.05. Conclusion: Our data revealed a high urinary ACE 1 activity, different than plasmatic level, in SCD patients suggesting a dissociation between the intrarenal and systemic RAAS. The increase of urinary ACE 1 activity in SCD patients suggests higher levels of Ang II with a predominance of classical RAAS axis, that can induce kidney damage.

Resumo Introdução: A nefropatia falciforme começa na infância e apresenta aumentos precoces na filtração glomerular, que, em longo prazo, podem levar à insuficiência renal crônica. Várias doenças têm aumentado a atividade da enzima conversora da angiotensina (ECA) urinária e circulante, mas há pouca informação sobre alterações na atividade das ECAs em crianças com doença falciforme (DF). Objetivo: Examinamos a atividade da ECA-1 circulante e urinária em crianças com DF. Métodos: Este estudo transversal comparou crianças que eram portadoras de DF com crianças que compunham um Grupo Controle (GC). As atividades séricas e urinárias da ECA foram avaliadas, assim como os fatores bioquímicos, a relação albumina/creatinina urinária e a taxa de filtração glomerular estimada. Resultados: A atividade urinária da ECA foi significativamente maior em pacientes com DF do que em crianças saudáveis (mediana 0,01; intervalo 0,00-0,07 vs mediana 0,00; intervalo 0,00-0,01 mU/mL·creatinina, p < 0,001. Não foi observada diferença significativa nas atividades séricas da ECA entre os grupos DF e GC (mediana 32,25; intervalo 16,2-59,3 vs mediana 40,9; intervalo 18,0-53,4) mU/mL·creatinina, p < 0,05. Conclusão: Nossos dados revelaram uma alta atividade urinária da ECA-1, diferente do nível plasmático, em pacientes com DF, sugerindo uma dissociação entre o Sistema Renina Angiotensina Aldosterona (SRAA) intra-renal e sistêmico. O aumento da atividade urinária da ECA-1 em pacientes com DF sugere níveis mais elevados de Ang II com predominância do eixo clássico do SRAA, que pode induzir lesão renal.

Interactions amongst inflammation, renin-angiotensin-aldosterone and kallikrein-kinin systems: suggestive approaches for COVID-19 therapy

Coronavirus disease 2019 (COVID-19) is a rapid-spread infectious disease caused by the SARS-CoV-2 virus, which can culminate in the renin-angiotensin-aldosterone (RAAS) and kallikrein-kinin (KKS) systems imbalance, and in serious consequences for infected patients. This scoping review of published research exploring the RAAS and KKS was undertaken in order to trace the history of the discovery of both systems and their multiple interactions, discuss some aspects of the viral-cell interaction, including inflammation and the system imbalance triggered by SARS-CoV-2 infection, and their consequent disorders. Furthermore, we correlate the effects of continued use of the RAAS blockers in chronic diseases therapies with the virulence and physiopathology of COVID-19. We also approach the RAAS and KKS-related proposed potential therapies for treatment of COVID-19. In this way, we reinforce the importance of exploring both systems and the application of their components or their blockers in the treatment of coronavirus disease.(AU)

Genomics and epidemiology of the P 1 SARS-CoV-2 lineage in Manaus, Brazil

Cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Manaus, Brazil, resurged in late 2020 despite previously high levels of infection. Genome sequencing of viruses sampled in Manaus between November 2020 and January 2021 revealed the emergence and circulation of a novel SARS-CoV-2 variant of concern. Lineage P.1 acquired 17 mutations, including a trio in the spike protein (K417T, E484K, and N501Y) associated with increased binding to the human ACE2 (angiotensin-converting enzyme 2) receptor. Molecular clock analysis shows that P.1 emergence occurred around mid-November 2020 and was preceded by a period of faster molecular evolution. Using a two-category dynamical model that integrates genomic and mortality data, we estimate that P.1 may be 1.7- to 2.4-fold more transmissible and that previous (non-P.1) infection provides 54 to 79% of the protection against infection with P.1 that it provides against non-P.1 lineages. Enhanced global genomic surveillance of variants of concern, which may exhibit increased transmissibility and/or immune evasion, is critical to accelerate pandemic responsiveness.

Factores moleculares implicados en insuficiencia cardiaca / Molecular factors involved in heart failure

La insuficiencia cardiaca se define como un síndrome caracterizado por la incapacidad de proveer las necesidades metabólicas del organismo, presentando disnea y fatiga. Hasta ahora, se ha descrito la participación de varias moléculas involucradas en los mecanismos de señalización intracelular que conducen a la insuficiencia cardiaca y estimulan la síntesis de algunas proteínas, como colágeno, la cual induce a una hipertrofia cardiaca(AU)

Heart failure is defined as a syndrome characterized by the inability to meet the metabolic needs of the organism, causing dyspnea and fatigue.Descriptions are available of the involvement of several molecules in cell signaling mechanisms which lead to heart failure and prompt the synthesis of some proteins, such as collagen, inducing cardiac hypertrophy(AU)

Informe diário de evidências COVID-19: busca referente aos dias 11, 12 e 13 de julho de 2020 / COVID-19 daily evidence report: search for July 11, 12 and 13, 2020

O Informe Diário de Evidências é uma produção do Ministério da Saúde que tem como objetivo acompanhar diariamente as publicações científicas sobre tratamento farmacológico e vacinas para a COVID-19. Dessa forma, são realizadas buscas estruturadas em bases de dados biomédicas, referentes ao dia anterior desse informe. Não são incluídos estudos pré-clínicos (in vitro, in vivo, in silico). A frequência dos estudos é demonstrada de acordo com a sua classificação metodológica (revisões sistemáticas, ensaios clínicos randomizados, coortes, entre outros). Para cada estudo é apresentado um resumo com avaliação da qualidade metodológica. Essa avaliação tem por finalidade identificar o grau de certeza/confiança ou o risco de viés de cada estudo. Para tal, são utilizadas ferramentas já validadas e consagradas na literatura científica, na área de saúde baseada em evidências. Cabe ressaltar que o documento tem caráter informativo e não representa uma recomendação oficial do Ministério da Saúde sobre a temática. Foram encontrados 14 artigos.

COVID-19, ACE -inhibitors and angiotensin receptor blockers: The need to differentiate between early infection and acute lung injury / COVID-19, y IECA -inhibidores y bloqueadores de los receptores de angiotensina: la necesidad de diferenciar entre una infección temprana y una lesión pulmonar aguda

SARS-CoV-2, along with SARS-CoV and MERS-CoV, forms part of the three highly pathogenic coronaviruses identified since the start of the millennium.1,2 While SARS-CoV was identified on 2003 and MERS-CoV on 2012, the initial reports of SARS-CoV-2 (the etiological agent of COVID-19) were first released at the end of December 2019.3,4 Now, after less than four months, the virus has distributed globally and has become the focus of extensive medical research, as the number of cases keeps rising.A significant part of the investigative effort has been directed to the search for an effective therapy or intervention that could stop the spread of the disease or be used to effectively treat infected patients. Likewise, potential predisposing factors to develop a more severe clinical presentation are progressively being identified. Some of the more relevant are older age and the presence of certain comorbidities, such as cerebrovascular and coronary heart disease, hypertension and diabetes.5­8 It is important to highlight that the last two are chronic conditions commonly treated with ACE-inhibitors and angiotensin II type-I receptor blockers.9­11 However, the evidence suggests that these medications can upregulate the expression of angiotensin converting enzyme 2 (ACE2), the cellular receptor for both SARS-CoV and SARS-CoV-2.11­16 Thus, a group of researchers hypothesized that ACE2-increasing drugs could raise the risk of infection and prompt a more severe clinical course or a fatal outcome in diabetic and hypertensive patients.

Menores niveles circulantes del péptido vasoactivo y cardioprotector angiotensina-(1-9) en pacientes con hipertension arterial pulmonar / Lower circulating levels of angiotensin-(1-9), a vasoactive and cardio-protective peptide in patients with pulmonary artery hypertension

RESUMEN: Introducción: La vía clásica del sistema renina-angiotensina (SRA) está activado en pacientes con hipertensión arterial pulmonar (HAP). Previamente, hemos encontrado que en la disfunción ventricular post infarto al miocardio experimental la activación del eje clásico del SRA, dado por la enzima convertidora de angiotensina I (ECA) y angiotensina (Ang ) II se correlaciona negativamente con el eje paralelo del SRA dado por la ECA homóloga (ECA2) y el péptido vasoactivo y cardioprotector Ang-(1-9). Resultados preclínicos muestran la eficacia de la administración de Ang-(1-9) en el tratamiento del remodelamiento cardiovascular patológico. Hasta la fecha no existen antecedentes de los niveles circulantes de Ang-(1-9) en pacientes con hipertensión arterial pulmonar comparados con sujetos sanos. Objetivo: Determinar los niveles circulantes del péptido vasoactivo y cardiprotector Ang-(1-9) en pacientes con HAP y compararlos con sujetos sanos pareados por edad y sexo. Métodos: Estudio comparativo transversal en pacientes con HAP (grupo I, OMS) con presión de arteria pulmonar media (mPAP) ≥25 mmHg bajo tratamiento con furosemida (40%), espironolactona (53%), Acenocumarol/Warfarina (47%), Bosentan/Ambrisentan (27%), Sildenafil (80%), iloprost (7%) y digoxina (13%). Los sujetos controles correspondieron a sujetos asintomáticos sanos sin enfermedad cardiovascular, cardiopatía estructural ni pulmonar (n=14). En todos los pacientes se determinó mPAP, proBNP, resistencia vascular pulmonar (RVP, WU), presión capilar pulmonar (PCP, mmHg), gasto cardíaco (L/min), capacidad funcional por test de caminata 6 minutos (TC6M), cambio del área fraccional del ventrículo derecho VD (FAC, %). Se utilizó prueba t de Student y programa estadístico SPSS10.0. Un valor de p < 0,05 fue considerado como estadísticamente significativo. Resultados: Los pacientes ingresados al estudio mostraron: etiología de la HAP, idiopática (86,7%), VIH (13,3%), capacidad funcional I (6,2%), II (68,3) y III (25%) y promedio mPAP 51,3±1,9. Pacientes con HAP (grupo I, OMS) versus sujetos sanos mostraron disminución significativa de FAC, actividad plasmática de la ECA2 y niveles circulantes de Ang-(1-9). En la vía clásica del RAAS pacientes con HAP mostraron mayor actividad plasmática de ECA y niveles circulantes e Ag II. Correlaciones significativas se encontraron entre niveles de Ang-(1-9) y mPAP (r = -0.701, p < 0,001) y Ang-(1-9) vs FAC (r = 0.549, p < 0,01). Conclusiones: En pacientes con HAP (grupo I, OMS), los niveles circulantes de Ang-(1-9) están significativamente disminuidos y se asocian inversamente con la PAP, severidad del remodelamiento y disfunción del ventrículo derecho. El uso terapéutico de Ang-(1-9) como agente vasodilatador y cardioprotector podría ser relevante y potencialmente útil, desde una perspectiva clínica, en la HAP. Ang-(1-9) podría reducir la PAP y mejorar el remodelamiento vascular y del ventrículo derecho en la HAP. Por lo tanto, este péptido podría ser útil como blanco terapéutico en la HAP.

ABSTRACTS: Classic renin-angiotensis pathway (RAP) is activated in patients with pulmonary artery hypertension (PAH). We have previously shown that in patients with post myocardial infarction systolic dysfunction the activation of RAP mediated by angiotensin converting enzyme (ACE) and angiotensin II (Ang II) is inversely correlated with the parallel RAP axis mediated by homologous ACE (ACE2) and by the vasoactive and cardioprotective peptide Ang-(1-9). Pre clinical studies show that administration of Ang-(1-9) leads to a favorable ventricular remodelling. At present there is no information regarding levels of Ang-(1-9) in PAH patients compared to healthy subjects. Methods: 16 PAH patients (WHO group 1), with mean PA pressure > 25mmHg being treated with furosemide (40%), Bosentan/Ambrisentan (27%), Sildenafil (80%), iloprost (7%) were compared with healthy subjects (n=14). mPAP, pro BNP, pulmonary vascular resistance (Wu), pulmonary capillary pressure (PCP mmHg), cardiac output (L/min), functional capacity (6 min walking test) (6mWT), and changes in right ventricular fractional area (RV FA), were measured in all subjects. Results: In HAP subjects, the eiotology of PAH was unknown in 87%, or HIV (13%). Functional class was I (6.2 %), II (68.3%) or III (25%). Mean PAP was 51.3±1.9. Compared to healthy subjects, PAH patients had significantly lower RV FA, ACE2 and Ang-(19) levels. Also they had greater ACE plasma activity and AngII circulating levels. Significant correlations were found between Ang-(1-9) and mPAP (-0.701, p < 0,001) and between Ang-(1-9) and RV FA (r = 0.549, p < 0,01). Conclusion: group I PAH subjects, circulating levels of Ang-(1-9) are significantly lower than in healthy subjects and are inversely related to PAP, severity of ventricular remodeling and right ventricular dysfunction. The use of Ang-(1-9) as a vasodilator and cardioprotector agent could be clinically useful in PAH subjects.

Influence of ACE polymorphism on echocardiographic data of patients with heart failure / Influência do polimorfismo da ECA nos dados ecocardiográficos de pacientes com insuficiência cardíaca

Background: Angiotensin converting enzyme (ACE) polymorphism has been associated with different clinical and echocardiographic parameters in patients with heart failure (HF). However, no studies have been investigated such association with HF caused by Chagas disease. Objectives: To perform a genetic study to evaluate the frequency of ACE polymorphism in patients with HF caused by Chagas disease attending a university hospital in the central-west region and its association with echocardiographic findings. Methods: Descriptive study of ACE polymorphism (I/D) and echocardiographic data of 103 patients with HF caused by Chagas disease. Echocardiographic parameters were compared between the genotypes using the ANOVA test. Results: Genotypic distribution of the ACE polymorphism was 16.5% DD, 57.3% DI and 26.2% II. There was no statistically significant difference in the distribution of genotypes between men and women. The echocardiographic findings were: left ventricular ejection fraction: 43.8 ± 14.8 (DD) vs. 42.3 ± 11.6 (ID) vs. 44.9 ± 13.0 (II), p = 0.664; left ventricular diastolic diameter: 59.2 ± 9.7 (DD) vs. 60.3 ± 7.6 (ID) vs. 59.7 ± 78.1 (II), p = 0.879; left ventricular systolic diameter: 48.6 ± 12.8 (DD) vs. 50.6 ± 9.7 (ID) vs. 49.3 ± 11.9 (II), p = 0.753; and left atrial volume: 44.9 ± 10.1 (DD) vs. 40.9 ± 9.6 (ID) vs. 38.2 ± 7.8 (II), p = 0.068. Significant correlation coefficients were found for gender, age, ethnicity, heart rate and dyslipidemia. Conclusion: ACE polymorphism was not associated with echocardiographic findings in patients with HF caused by Chagas disease

Novas angiotensinas e suas implicações fisiológicas / Novel angiotensin peptides and their physiological implications

Introdução: O sistema renina-angiotensina (SRA) é a maior rede regulatória da pressão arterial, do balanço hidroeletrolítico e da homeostase do organismo. Desde que o papel do SRA na regulação da função cardiovascular foi descrito, os componentes do eixo endócrino do sistema, em especial a angiotensina II - na regulação e fisiologia cardiovascular e renal, têm sido foco de pesquisa. Os achados das últimas décadas, no entanto, mostraram que o sistema é muito mais complexo e intricado do que se imaginava. Objetivo: Apresentar, através de uma revisão da literatura, alguns dos novos elementos que compõem o SRA e suas implicações fisiológicas, atualizando o leitor sobre o estado da arte. Material de Métodos:Revisão bibliográfica abordando as principais publicações, indexadas pelo PubMed, relacionadas aos novos peptídeos do SRA. Resultados: Dentre os novos componentes do SRA, encontram-se a angiotensina­(1-9), um nonapeptídeo que promove vasodilatação, ação anti-hipertrófica em cardiomiócitos e ação anti-hipertensiva. A Angiotensina-(1-7), por sua vez, apesar de se diferenciar da Ang II apenas pela ausência de um único aminoácido, é responsável por efeitos fisiológicos opostos aos observados com a Ang II. A Angiotensina A, outro peptídeo biologicamente ativo, é formado a partir da descarboxilação do aspartato, desempenhando efeitos semelhantes à Ang II. A Alamandina, também derivada de uma descarboxilação, é um heptapeptídeo vasodilatador, anti-hipertensivo e cardioprotetor. Conclusão: Os achados envolvendo as novas angiotensinas permitem o entendimento do sistema como uma extensa rede composta de vias e eixos alternativos, muitos dos quais, ainda sem esclarecimento científico. O enfoque em novas vias de formação de produtos com funções biológicas poderá ser útil para o desenvolvimento de novas estratégias terapêuticas e, descobertas no campo da fisiologia e fisiopatologia de uma série de condições.

Introdution: The renin-angiotensin system (RAS) is the major regulatory system of arterial blood pressure, hydroelectrolytic balance, and body homeostasis. Since the role of the RAS in the cardiovascular function has been described, much of the research in this area has focused on the role of its endocrine axis components, mainly angiotensin II (Ang II), in the cardiovascular and renal physiology. Over the last decades, the findings have shown that the system is much more intricate than thought. Objective:To present, upon a literature review, some of the new elements about the RAS and its physiological implications, updating the reader about the state of the art. Methods Material: Bibliographic review addressing the main PubMed publications related of the novels angiotensin-peptides. Results: Among the novel RAS components, angiotensin­(1-9) is a nonapeptide that exerts antihypertrophy effects in cardiomyocytes, and vasodilatory and anti-hypertensive actions. Angiotensin-(1-7), which differs from Ang II due to the absence of only one aminoacid, is responsible for physiological effects opposite to those of Ang II. Angiotensin A, another biologically active peptide, is synthesized through aspartate decarboxylation, and exerts effects similar to those of Ang II. Alamandine, also formed through decarboxylation, is a heptapeptide showing vasodilatory, antihypertensive, and cardioprotective effects. Conclusion: The discovery of novel angiotensins sheds more light on the view that the RAS is an extensive regulatory system with pathways and alternative axis, much of which without scientific knowledge. Scientific efforts envisioning novel formation pathways of biologically active products may be useful for development of innovative therapeutic strategies and discoveries in the field of several physiological and pathological conditions.

Angiotensin Receptor Blockers as an Alternative to Angiotensin-Converting Enzyme Inhibitors in Patients with Acute Myocardial Infarction Undergoing Percutaneous Coronary Intervention

BACKGROUND: Angiotensin-converting enzyme inhibitors (ACEIs) are the first choice for the treatment of acute myocardial infarction (AMI), and angiotensin receptor blockers (ARBs) should be considered in patients intolerant to ACEIs. Although previous studies support the use of ARBs as an alternative to ACEIs, these studies showed inconsistent results. The objective of this study was to demonstrate the clinical impact of ARBs as an alternative to ACEIs in patients with AMI undergoing percutaneous coronary intervention (PCI). METHODS: The CardiOvascular Risk and idEntificAtion of potential high-risk population in AMI (COREA-AMI) registry enrolled all consecutive patients with AMI undergoing PCI. The primary endpoint was the composite of cardiovascular death, myocardial infarction, stroke, or hospitalization due to heart failure. RESULTS: Of the 3,328 eligible patients, ARBs replaced ACEIs in 816 patients, while 824 patients continued to use ACEIs and 826 patients continued to use ARBs. The remaining 862 patients did not receive ACEIs/ARBs. After the adjustment with inverse probability weighting, the primary endpoints in the first groups were similar (7.5% vs. 8.0%, hazard ratio [HR], 0.89; 95% confidence interval [CI], 0.75–1.05; P = 0.164). Composite events were less frequent in the ACEI to ARB group than no ACEI/ARB group (7.5% vs. 11.8%, HR, 0.76; 95% CI, 0.64–0.90; P = 0.002). CONCLUSION: The alternative use of ARBs following initial treatment with ACEIs demonstrates comparable clinical outcomes to those with continued use of ACEIs and is associated with an improved rate of composite events compared to no ACEI/ARB use in patients with AMI undergoing PCI. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02385682

Angiotensin II and TGF-β1 Induce Alterations in Human Amniotic Fluid-Derived Mesenchymal Stem Cells Leading to Cardiomyogenic Differentiation Initiation

BACKGROUND AND OBJECTIVES: Human amniotic fluid-derived mesenchymal stem cells (AF-MSCs) may be a valuable source for cardiovascular tissue engineering and cell therapy. The aim of this study is to verify angiotensin II and transforming growth factor-beta 1 (TGF-β1) as potential cardiomyogenic differentiation inducers of AF-MSCs. METHODS AND RESULTS: AF-MSCs were obtained from amniocentesis samples from second-trimester pregnant women, isolated and characterized by the expression of cell surface markers (CD44, CD90, CD105 positive; CD34 negative) and pluripotency genes (OCT4, SOX2, NANOG, REX1). Cardiomyogenic differentiation was induced using different concentrations of angiotensin II and TGF-β1. Successful initiation of differentiation was confirmed by alterations in cell morphology, upregulation of cardiac genes-markers NKX2-5, TBX5, GATA4, MYH6, TNNT2, DES and main cardiac ion channels genes (sodium, calcium, potassium) as determined by RT-qPCR. Western blot and immunofluorescence analysis revealed the increased expression of Connexin43, the main component of gap junctions, and Nkx2.5, the early cardiac transcription factor. Induced AF-MSCs switched their phenotype towards more energetic and started utilizing oxidative phosphorylation more than glycolysis for energy production as assessed using Agilent Seahorse XF analyzer. The immune analysis of chromatin-modifying enzymes DNMT1, HDAC1/2 and Polycomb repressive complex 1 and 2 (PRC1/2) proteins BMI1, EZH2 and SUZ12 as well as of modified histones H3 and H4 indicated global chromatin remodeling during the induced differentiation. CONCLUSIONS: Angiotensin II and TGF-β1 are efficient cardiomyogenic inducers of human AF-MSCs; they initiate alterations at the gene and protein expression, metabolic and epigenetic levels in stem cells leading towards cardiomyocyte-like phenotype formation.

Angiotensin II Type 1 Receptor Blocker, Fimasartan, Reduces Vascular Smooth Muscle Cell Senescence by Inhibiting the CYR61 Signaling Pathway

BACKGROUND AND OBJECTIVES: Angiotensin II (Ang II) has been suggested to accelerate vascular senescence, however the molecular mechanism(s) remain unknown. METHODS: We cultured human coronary artery smooth muscle cells (hCSMCs) and treated Ang II and/or fimasartan. Or we transfected adenoviral vectors expressing CYR61 (Ad-CYR61) or antisense CYR61 (Ad-As-CYR61). Cellular senescence was evaluated senescence-associated β-galactosidase (SA-β-gal) assay. The molecular mechanisms were investigated real-time PCR and western blots. RESULTS: SA-β-gal-positive cells significantly increased in Ang II-treated hCSMCs (5.77±1.43-fold compared with the control). The effect of Ang II was significantly attenuated by pretreatment with the Ang II type 1 receptor blocker, fimasartan (2.00±0.92-fold). The expression of both p53 and p16 senescence regulators was significantly increased by Ang II (p53: 1.39±0.17, p16: 1.19±0.10-fold vs. the control), and inhibited by fimasartan. Cysteine-rich angiogenic protein 61 (CYR61) was rapidly induced by Ang II. Compared with the control, Ad-CYR61-transfected hCSMCs showed significantly increased SA-β-gal-positive cells (3.47±0.65-fold). Upon transfecting Ad-AS-CYR61, Ang II-induced senescence (3.74±0.23-fold) was significantly decreased (1.77±0.60-fold). p53 expression by Ang II was significantly attenuated by Ad-AS-CYR61, whereas p16 expression was not regulated. Ang II activated ERK1/2 and p38 MAPK, which was significantly blocked by fimasartan. ERK and p38 inhibition both regulated Ang II-induced CYR61 expression. However, p53 expression was only regulated by ERK1/2, whereas p16 expression was only attenuated by p38 MAPK. CONCLUSIONS: Ang II induced vascular senescence by the ERK/p38 MAPK–CYR61 pathway and ARB, fimasartan, protected against Ang II-induced vascular senescence.

Benefits of Angiotensin Receptor Blockade: Preventing Smooth Muscle Cell Senescence and Beyond

No abstract available.