Search results for "Renin-Angiotensin"

Free radical biology of the cardiovascular system

2012

Most cardiovascular diseases (CVDs), as well as age-related cardiovascular alterations, are accompanied by increases in oxidative stress, usually due to increased generation and/or decreased metabolism of ROS (reactive oxygen species; for example superoxide radicals) and RNS (reactive nitrogen species; for example peroxynitrite). The superoxide anion is generated by several enzymatic reactions, including a variety of NADPH oxidases and uncoupled eNOS (endothelial NO synthase). To relieve the burden caused by this generation of free radicals, which also occurs as part of normal physiological processes, such as mitochondrial respiratory chain activity, mammalian systems have developed endogen…

Obesity and Outcomes in COVID-19: When an Epidemic and Pandemic Collide.

2020

Obesity has reached epidemic proportions in the United States and in much of the westernized world, contributing to considerable morbidity. Several of these obesity-related morbidities are associated with greater risk for death with coronavirus disease 2019 (COVID-19). Severe acute respiratory syndrome coronavirus 2 penetrates human cells through direct binding with angiotensin-converting enzyme 2 receptors on the cell surface. Angiotensin-converting enzyme 2 expression in adipose tissue is higher than that in lung tissue, which means that adipose tissue may be vulnerable to COVID-19 infection. Obese patients also have worse outcomes with COVID-19 infection, including respiratory failure, n…

Mechanisms of Increased Vascular Superoxide Production in an Experimental Model of Idiopathic Dilated Cardiomyopathy

2005

Objective— In the present study, we sought to identify mechanisms underlying increased oxidative stress in vascular tissue in an experimental animal model of chronic congestive heart failure (CHF). Methods and Results— Superoxide and nitric oxide (NO) was measured in vessels from cardiomyopathic hamsters (CHF hamsters) and golden Syrian hamsters. We also determined expression of endothelial nitric oxide synthase (NOSIII), the soluble guanylyl cyclase, the cGMP-dependent kinase, and the NADPH oxidase. To analyze the contribution of the renin-angiotensin system to oxidative stress, CHF hamsters were treated with the angiotensin-converting enzyme inhibitor captopril for 200 days (120 mg · kg …

Unraveling the mechanisms of action of lactoferrin-derived antihypertensive peptides: ACE inhibition and beyond

2015

Hypertension is one of the most important causes of cardiovascular and renal morbidity and mortality, and it represents a serious health problem in Western countries. Over the last few decades scientific interest in food-derived antihypertensive peptides has grown as an alternative to drugs in the control of systemic blood pressure. Most of these peptides target the angiotensin I-converting enzyme (ACE) but emerging evidence points to other antihypertensive mechanisms beyond ACE inhibition. The milk protein lactoferrin (LF) is a good source of orally active antihypertensive peptides the characterization of which, including ex vivo functional assays and in vivo approaches, shows that they mi…

Efficacy and safety of combined neprilysin and RAS inhibition in heart failure: Let's leave the doubts behind

2020

Sodium zirconium cyclosilicate: a new potassium binder for the treatment of hyperkalemia

2018

Hyperkalemia is one of the most common electrolyte disturbances, especially among some groups of patients, such as in those with chronic kidney disease, diabetes or heart failure. Hyperkalemia has been associated with increased risks of mortality, arrhythmias, hospitalization and costs, as well as the need to down titrate/discontinue renin-angiotensin-aldosterone system inhibitors (RAASIs), despite their well-known cardiovascular and nephroprotective benefits. Current potassium binders have limitations (slow onset of action, limited selectivity for potassium binding, risk of drug interactions or gastrointestinal intolerance). Sodium zirconium cyclosilicate (SZC) is a new potassium binder re…

SARS CoV2 infection _The longevity study perspectives

2021

Graphical abstract

Delayed inhibition of angiotensin II receptor type 1 reduces secondary brain damage and improves functional recovery after experimental brain trauma*

2011

OBJECTIVE:: To investigate the regulation of the cerebral renin-angiotensin system and the effect of angiotensin II receptor type 1 inhibition on secondary brain damage, cerebral inflammation, and neurologic outcome after head trauma. DESIGN:: The expression of renin-angiotensin system components was determined at 15 mins, 3 hrs, 6 hrs, 12 hrs, and 24 hrs after controlled cortical impact in mice. Angiotensin II receptor type 1 was inhibited using candesartan (0.1, 0.5, 1 mg/kg) after trauma to determine its effect on secondary brain damage, brain edema formation, and inflammation. The window of opportunity was tested by delaying angiotensin II receptor type 1 inhibition for 30 mins, 1 hr, 2…

Age and Multimorbidity Predict Death Among COVID-19 Patients: Results of the SARS-RAS Study of the Italian Society of Hypertension

2020

Several factors have been proposed to explain the high death rate of the coronavirus disease 2019 (COVID-19) outbreak, including hypertension and hypertension-related treatment with Renin Angiotensin System inhibitors. Also, age and multimorbidity might be confounders. No sufficient data are available to demonstrate their independent role. We designed a cross-sectional, observational, multicenter, nationwide survey in Italy to verify whether renin-angiotensin system inhibitors are related to COVID-19 severe outcomes. We analyzed information from Italian patients diagnosed with COVID-19, admitted in 26 hospitals. One thousand five hundred ninety-one charts (male, 64.1%; 66±0.4 years) were r…

Serum uric acid is not independently associated with plasma renin activity and plasma aldosterone in hypertensive adults

2017

Background and Aims In experimental investigations conducted in rats, raising serum uric acid (SUA) levels resulted in the stimulation of intrarenal renin expression. Studies in humans exploring the association of SUA with plasma renin activity (PRA) yielded conflicting results. Moreover, little is known about the relationship of SUA with plasma aldosterone concentration (PAC). The study aimed to assess the relationship between SUA levels, PRA, and PAC and the influence of age, gender, body mass index (BMI), and hyperuricemia on these relationships in subjects with essential hypertension (EH). Methods and Results We enrolled 372 hypertensive patients (mean age 45 ± 12 years, men 67%) with u…