scholarly journals Losartan Mitigates Oxidative Stress in the Brains of Aged IL10-/- Mice

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. 684-684
Author(s):  
Nazaneen Saleh ◽  
Caglar Cosarderelioglu ◽  
Peter M Abadir ◽  
Ramya Vajapey ◽  
Jeremy D Walston
Keyword(s):  
Oxidative Stress ◽  
Chronic Inflammation ◽  
Renin Angiotensin System ◽  
Tau Proteins ◽  
Oxidative Stress Marker ◽  
Contributory Factor ◽  
Angiotensin System ◽  
Hippocampal Tissue ◽  
The Impact ◽  
Losartan Treatment

Abstract Chronic inflammation has been linked to frailty and declined cognition in older adults. Activation of the renin-angiotensin system (RAS) through the angiotensin Type1 receptor (AT1R) has been suggested as a contributory factor that links both inflammation and aging. Here we examined the impact of 4 weeks of oral Losartan treatment on IL10-/- mice brains, a mouse model of chronic inflammation and frailty. Frontal cortex, cerebellar, and hippocampal tissue of aged (100 weeks old) male IL10-/- mice were studied. Western blot techniques were employed to quantify changes in brain AT1R, nitrotyrosine (NT) as an oxidative stress marker, and Tau proteins. Our data show that aged IL-10 mice have significantly higher levels of AT1R in the cortex tissue but not in cerebellar or hippocampal tissue compared to age and sex-matched WT mice (0.63 + 0.35 vs 1.5 + 0.54, WT vs IL10, respectively, P<0.004). When treated with LOS, brain cortical tissue of IL10 -/- mice showed significant decreases in levels of AT1R (1.5 + 0.54 vs 0.98 + 0.50, IL10 vs LOS treated IL10, respectively, P<0.04), NT (0.72 + 0.12 vs 0.42 + 0.10, IL10 vs LOS treated IL10, respectively, P<0.009), and Tau protein (1.3 + 0.31 vs 0.15 + 0.08, IL10 vs LOS treated IL10, respectively, P<0.004) as compared to control IL10-/- mice. Losartan treatment had no significant effect on hippocampal AT1R or NT levels. Our results highlight the impact of Losartan, a drug commonly prescribed for the treatment of high blood pressure, on the brain-specific angiotensin system and its downstream effects on brain oxidative stress and Tau pathology.

Aortic Stenosis, Aortic Regurgitation and Arterial Hypertension

2019 ◽  
Vol 17 (2) ◽  
pp. 180-190 ◽  
Author(s):  
V. Katsi ◽  
G. Georgiopoulos ◽  
D. Oikonomou ◽  
C. Aggeli ◽  
C. Grassos ◽  
...  
Keyword(s):  
Aortic Valve ◽  
Aortic Stenosis ◽  
Aortic Regurgitation ◽  
Antihypertensive Agents ◽  
Renin Angiotensin System ◽  
Aortic Disease ◽  
Review Of The Literature ◽  
Angiotensin System ◽  
The Impact ◽  
Worse Prognosis

Background: Hypertension (HT) is an important risk factor for cardiovascular disease and might precipitate pathology of the aortic valve. </P><P> Objective: To investigate the association of HT with aortic dysfunction (including both aortic regurgitation and stenosis) and the impact of antihypertensive treatment on the natural course of underlying aortic disease. </P><P> Methods: We performed a systematic review of the literature for all relevant articles assessing the correlation between HT and phenotype of aortic disease. </P><P> Results: Co-existence of HT with aortic stenosis and aortic regurgitation is highly prevalent in hypertensive patients and predicts a worse prognosis. Certain antihypertensive agents may improve haemodynamic parameters (aortic jet velocity, aortic regurgitation volume) and remodeling of the left ventricle, but there is no strong evidence of benefit regarding clinical outcomes. Renin-angiotensin system inhibitors, among other vasodilators, are well-tolerated in aortic stenosis. </P><P> Conclusion: Several lines of evidence support a detrimental association between HT and aortic valve disease. Therefore, HT should be promptly treated in aortic valvulopathy. Despite conventional wisdom, specific vasodilators can be used with caution in aortic stenosis.

scholarly journals Outcomes of COVID-19 Hospitalized Patients Previously Treated with Renin-Angiotensin System Inhibitors

2020 ◽  
Vol 9 (11) ◽  
pp. 3472 ◽  
Author(s):  
Elena-Mihaela Cordeanu ◽  
Lucas Jambert ◽  
Francois Severac ◽  
Hélène Lambach ◽  
Jonathan Tousch ◽  
...  
Keyword(s):  
Renin Angiotensin System ◽  
Severe Pneumonia ◽  
University Hospital ◽  
Angiotensin System ◽  
Angiotensin Converting Enzyme 2 ◽  
Renin Angiotensin ◽  
Previously Treated ◽  
The Impact ◽  
Harmful Effects ◽  
Observation Period

(1) Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) penetrates respiratory epithelium through angiotensin-converting enzyme-2 binding, raising concerns about the potentially harmful effects of renin–angiotensin system inhibitors (RASi) on Human Coronavirus Disease 2019 (COVID-19) evolution. This study aimed to provide insight into the impact of RASi on SARS-CoV-2 outcomes in patients hospitalized for COVID-19. (2) Methods: This was a retrospective analysis of hospitalized adult patients with SARS-CoV-2 infection admitted to a university hospital in France. The observation period ended at hospital discharge. (3) Results: During the study period, 943 COVID-19 patients were admitted to our institution, of whom 772 were included in this analysis. Among them, 431 (55.8%) had previously known hypertension. The median age was 68 (56–79) years. Overall, 220 (28.5%) patients were placed under mechanical ventilation and 173 (22.4%) died. According to previous exposure to RASi, we defined two groups, namely, “RASi” (n = 282) and “RASi-free” (n = 490). Severe pneumonia (defined as leading to death and/or requiring intubation, high-flow nasal oxygen, noninvasive ventilation, and/or oxygen flow at a rate of ≥5 L/min) and death occurred more frequently in RASi-treated patients (64% versus 53% and 29% versus 19%, respectively). However, in a propensity score-matched cohort derived from the overall population, neither death (hazard ratio (HR) 0.93 (95% confidence interval (CI) 0.57–1.50), p = 0.76) nor severe pneumonia (HR 1.03 (95%CI 0.73–1.44), p = 0.85) were associated with RASi therapy. (4) Conclusion: Our study showed no correlation between previous RASi treatment and death or severe COVID-19 pneumonia after adjustment for confounders.

Resveratrol ameliorates the cyclosporine-induced vascular and renal impairments: possible impact of the modulation of renin–angiotensin system

2019 ◽  
Vol 97 (12) ◽  
pp. 1115-1123 ◽  
Author(s):  
Seldag Bekpinar ◽  
Ece Karaca ◽  
Selin Yamakoğlu ◽  
F. İlkay Alp-Yıldırım ◽  
Vakur Olgac ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Angiotensin Converting Enzyme ◽  
Renin Angiotensin System ◽  
Immunosuppressive Drug ◽  
Oxidative Stress Marker ◽  
Converting Enzyme ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
System Components ◽  
Renal Tubular

Cyclosporine, an immunosuppressive drug, exhibits a toxic effect on renal and vascular systems. The present study investigated whether resveratrol treatment alleviates renal and vascular injury induced by cyclosporine. Cyclosporine (25 mg/kg per day, s.c.) was given for 7 days to rats either alone or in combination with resveratrol (10 mg/kg per day, i.p.). Relaxation and contraction responses of aorta were examined. Serum levels of blood urea nitrogen, creatinine, angiotensin II, and angiotensin 1-7 were measured. Histopathological examinations as well as immunostaining for 4-hydroxynonenal and nitrotyrosine were performed in the kidney. RNA expressions of renin–angiotensin system components were also measured in renal and aortic tissues. Cyclosporine decreased the endothelium-dependent relaxation and increased vascular contraction in the aorta. It caused renal tubular degeneration and increased immunostaining for 4-hydroxynonenal, an oxidative stress marker. Cyclosporine also caused upregulations of the vasoconstrictive renin–angiotensin system components in renal (angiotensin-converting enzyme) and aortic (angiotensin II type 1 receptor) tissues. Resveratrol co-treatment prevented the cyclosporine-related deteriorations. Moreover, it induced the expressions of vasodilatory effective angiotensin-converting enzyme 2 and angiotensin II type 2 receptor in aorta and kidney, respectively. We conclude that resveratrol may be effective in preventing cyclosporine-induced renal tubular degeneration and vascular dysfunction at least in part by modulating the renin–angiotensin system.

scholarly journals The Biochemical Effects of Angiotensin-(1-7) on the Oxidative Stress Metabolism and Their Specific Parameters from the Temporal Lobe

2020 ◽  
Vol 71 (6) ◽  
pp. 307-311
Author(s):  
Sorin Ungurianu ◽  
Constantin Trus ◽  
Roxana-Rosmary Enciu
Keyword(s):  
Oxidative Stress ◽  
Temporal Lobe ◽  
Renin Angiotensin System ◽  
Ang Ii ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Angiotensin Peptides ◽  
Vascular Area ◽  
Ang Iv ◽  
The One

It is already known from a variety of previous reports that an independent brain renin�angiotensin system (RAS) exists, completely separated from the one in the periphery. This independent brain RAS has all the precursors and the enzymatic structures necessary for the generation of the angiotensin peptides. Thus, in the last few years various groups started focusing on the more central effects of less known angiotensins (e.g in comparison with Angiotensin (Ang) II), namely Ang III, Ang IV, Ang-(1�7) or Ang 5-8. One of these newly emerging angiotensins which has become an increased center of interest in many studies is Ang-(1-7), which is a heptapeptide previously described especially for its opposite effects to Ang II, in the peripheral vascular area, but also described for some opposite central functions vs. Ang II. These aspects are completed with the fact that it was recently suggested that the renin�angiotensin system could modulate the oxidative stress metabolism, and also it seems that the manifestations of Angiotensin-(1-7) on the basal oxidative stress status are contradictory, with a variety of reports describing controversial (e.g. both pro-oxidant and antioxidant actions) effects for this heptapeptide. Our results presented here are confirming a possible antioxidant effect of Ang-(1�7) administration on rat, as shown by the increased levels of antioxidant enzymes from the temporal lobe (superoxide dismutase and glutathione peroxidase) and decreased levels of malondialdehyde, as an important lipid peroxidation parameter.

scholarly journals The renin angiotensin system, oxidative stress and mitochondrial function in obesity and insulin resistance

2017 ◽  
Vol 1863 (5) ◽  
pp. 1106-1114 ◽  
Author(s):  
Latha Ramalingam ◽  
Kalhara Menikdiwela ◽  
Monique LeMieux ◽  
Jannette M. Dufour ◽  
Gurvinder Kaur ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Insulin Resistance ◽  
Mitochondrial Function ◽  
Renin Angiotensin System ◽  
Angiotensin System ◽  
Renin Angiotensin

Gene variants of the renin–angiotensin system and hypertension: from a trough of disillusionment to a welcome phase of enlightenment?

2010 ◽  
Vol 118 (8) ◽  
pp. 487-506 ◽  
Author(s):  
Gavin R. Norton ◽  
Richard Brooksbank ◽  
Angela J. Woodiwiss
Keyword(s):  
Association Studies ◽  
Large Population ◽  
Renin Angiotensin System ◽  
Human Populations ◽  
Incomplete Penetrance ◽  
Gene Variants ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Ras Genes ◽  
The Impact

There is substantial evidence to suggest that BP (blood pressure) is an inherited trait. The introduction of gene technologies in the late 1980s generated a sharp phase of over-inflated prospects for polygenic traits such as hypertension. Not unexpectedly, the identification of the responsible loci in human populations has nevertheless proved to be a considerable challenge. Common variants of the RAS (renin–angiotensin system) genes, including of ACE (angiotensin-converting enzyme) and AGT (angiotensinogen) were some of the first shown to be associated with BP. Presently, ACE and AGT are the only gene variants with functional relevance, where linkage studies showing relationships with hypertension have been reproduced in some studies and where large population-based and prospective studies have demonstrated these genes to be predictors of hypertension or BP. Nevertheless, a lack of reproducibility in other linkage and association studies has generated scepticism that only a concerted effort to attempt to explain will rectify. Without these explanations, it is unlikely that this knowledge will translate into the clinical arena. In the present review, we show that many of the previous concerns in the field have been addressed, but we also argue that a considerable amount of careful thought is still required to achieve enlightenment with respect to the role of RAS genes in hypertension. We discuss whether the previously identified problems of poor study design have been completely addressed with regards to the impact of ACE and AGT genes on BP. In the context of RAS genes, we also question whether the significance of ‘incomplete penetrance’ through associated environmental, phenotypic or physiological effects has been duly accounted for; whether appropriate consideration has been given to epistatic interactions between genes; and whether future RAS gene studies should consider variation across the gene by evaluating ‘haplotypes’.

Abstract 1375: Brain Renin Angiotensin Blockade Attenuates Cytokines and Oxidative Stress in the Paraventricular Nucleus of Hypothalamus and Decreases Sympathoexcitation in Heart Failure Rats

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Ying Ma ◽  
Yu-Ming Kang* ◽  
Zhi-Ming Yang ◽  
Joseph Francis*
Keyword(s):  
Oxidative Stress ◽  
Heart Failure ◽  
Paraventricular Nucleus ◽  
Cross Talk ◽  
Renin Angiotensin System ◽  
Heart Weight ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
The Brain ◽  
And Oxidative Stress

Introduction: Neurohumoral mechanisms play an important role in the pathophysiology of congestive heart failure (HF). Recent studies suggest that the brain renin angiotensin system (RAS) plays an important role in regulating body fluids and sympathetic drive in HF. In addition, it has been shown that there is cross talk between cytokines and RAS in cardiovascular disease. In this study we determined whether blockade of brain RAS attenuate inflammatory cytokines and oxidative stress in HF rats. Methods and Results: Adult male Sprague-Dawley rats were implanted with intracerebroventricular (ICV) cannulae and subjected to coronary artery ligation to induce HF and confirmed by echocardiography. Rats were treated with an angiotensin type 1 receptors (AT1-R) antagonist losartan (LOS, 20 μg/hr, ICV) or vehicle (VEH) for 4 weeks. At the end of the study, left ventricular (LV) function was measured by echocardiography and rats were sacrificed, and brain and plasma samples were collected for measurements of cytokines and superoxide using immunohistochemistry, Western blot and real time RT-PCR. HF rats induced significant increases in Nuclear Factor-kappaB (NF-κB) p50-positive neurons and activated microglia in the paraventricular nucleus (PVN) of hypothalamus, and TNF-α, IL-1β, IL-6 and NF-κB p50 in hypothalamus when compared with sham rats. These animals also had increased staining for dihydroethidium (DHE) and plasma levels of norepinephrine (NE), an indirect indicator of sympathetic activity. In contrast, ICV treatment with LOS attenuated cytokine expression and oxidative stress in the PVN and hypothalamus when compared with VEH treated HF rats. ICV treatment with LOS also reduced plasma NE levels, and proinflammatory cytokine, heart weight to body weight ratio with decreased LV end-diastolic pressure. Conclusions : These findings suggest the cross talk between the cytokines and renin angiotensin system within the brain contribute to sympatho-excitation in HF.

scholarly journals Açaí (Euterpe oleracea Mart.) seed extract protects against hepatic steatosis and fibrosis in high-fat diet-fed mice: Role of local renin-angiotensin system, oxidative stress and inflammation

2020 ◽  
Vol 65 ◽  
pp. 103726 ◽  
Author(s):  
Matheus Henrique Romão ◽  
Graziele Freitas de Bem ◽  
Izabelle Barcellos Santos ◽  
Ricardo de Andrade Soares ◽  
Dayane Teixeira Ognibene ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Hepatic Steatosis ◽  
High Fat Diet ◽  
Renin Angiotensin System ◽  
Seed Extract ◽  
Euterpe Oleracea ◽  
High Fat ◽  
Angiotensin System ◽  
Euterpe Oleracea Mart
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