Effect of renin angiotensin blockers on angiotensin converting enzyme 2 level in cardiovascular patients.

BACKGROUND: Renin-angiotensin-aldosterone system (RAAS) is hypothesized to be in the center of COVID pathophysiology as the angiotensin converting enzyme 2 (ACE2) represents the main entrance of the virus, thus there is a need to address the effect of chronic use of RAAS blockers, as in case of treatment of cardiovascular diseases, on the expression of ACE2. Accordingly, this study aimed to clarify the effect of ACE inhibitors (ACEIs) and angiotensin-receptor blockers (ARBs) on ACE2 and to assess the correlation between ACE2 and several anthropometric and clinic-pathological factors. METHODS: A total of 40 healthy controls and 60 Egyptian patients suffering from chronic cardiovascular diseases were enrolled in this study. Patients were divided into 40 patients treated with ACEIs and 20 patients treated with ARBs. Serum ACE2 levels were assessed by ELISA. RESULTS: Assessment of serum ACE2 level in different groups showed a significant difference between ACEIs and healthy groups and ACEIs and ARBs group, while there was no difference between ARBs and healthy. Multivariate analysis using ACE2 level as constant and age, female sex, ACEIs use and myocardial infarction (MI) showed that there was a significant effect of female sex and ACEIs use on ACE2 level with no effect of age, MI and diabetes. CONCLUSION: ACE2 levels varied between ACEIs and ARBs. It tends to be lower in ACEIs group and there is a strong positive association between ACE2 level and the female sex. This needs to be considered in Future studies to further understand the relationship between gender, sex hormones and ACE2 level. TRIAL REGISTRATION: Retrospectively registered ClinicalTrials.gov ID: NCT05418361 (June 2022).

Renin-Angiotensin-Aldosterone Inhibitors and COVID-19 Infection.

PURPOSE OF REVIEW: This review summarises the literature data and provides an overview of the role and impact of the use of renin-angiotensin-aldosterone system (RAAS) inhibitors in patients with coronavirus disease 2019 (COVID-19) infection. RECENT FINDINGS: The angiotensin-converting enzyme 2 (ACE2) has a key role in the regulation of the RAAS pathway, downregulating angiotensin II and attenuating inflammation, vasoconstriction and oxidative stress. Additionally, it plays an instrumental part in COVID-19 infection as it facilitates the cell entry of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and enables its replication. The use and role of RAAS inhibitors therefore during the COVID-19 pandemic have been intensively investigated. Although it was initially assumed that RAAS inhibitors may relate to worse clinical outcomes and severe disease, data from large studies and meta-analyses demonstrated that they do not have an adverse impact on clinical outcomes or prognosis. On the contrary, some experimental and retrospective observational cohort studies showed a potential protective mechanism, although this effect remains to be seen in large clinical trials.

Hunting for protective drugs at the break of a pandemic: Causal inference from hospital data.

At the break of a pandemic, the protective efficacy of therapeutic interventions needs rapid evaluation. An experimental approach to the problem will not always be appropriate. An alternative route are observational studies, whether based on regional health service data or hospital records. In this paper, we discuss the use of methods of causal inference for the analysis of such data, with special reference to causal questions that may arise in a pandemic. We apply the methods by using the aid of a directed acyclic graph (DAG) representation of the problem, to encode our causal assumptions and to logically connect the scientific questions. We illustrate the usefulness of DAGs in the context of a controversy over the effects of renin aldosterone system inhibitors (RASIs) in hypertensive individuals at risk of (or affected by) severe acute respiratory syndrome coronavirus 2 disease. We consider questions concerning the existence and the directions of those effects, their underlying mechanisms, and the possible dependence of the effects on context variables. This paper describes the cognitive steps that led to a DAG representation of the problem, based on background knowledge and evidence from past studies, and the use of the DAG to analyze our hospital data and assess the interpretive limits of the results. Our study contributed to subverting early opinions about RASIs, by suggesting that these drugs may indeed protect the older hypertensive Covid-19 patients from the consequences of the disease. Mechanistic interaction methods revealed that the benefit may be greater (in a sense to be made clear) in the older stratum of the population.

Mechanical dependency of the SARS-CoV-2 virus and the renin-angiotensin-aldosterone (RAAS) axis: a possible new threat.

Pathogens in our environment can act as agents capable of inflicting severe human diseases. Among them, the SARS-CoV-2 virus has recently plagued the globe and paralyzed the functioning of ordinary human life. The virus enters the cell through the angiotensin-converting enzyme-2 (ACE-2) receptor, an integral part of the renin-angiotensin system (RAAS). Reports on hypertension and its relation to the modulation of the RAAS are generating interest in the scientific community. This short review focuses on the SARS-CoV-2 infection's direct and indirect effects on our body through modulation of the RAAS axis. A patient having severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection, which causes COVID-19 relates to hypertension as a pre-existing disease or develops it in a post-COVID scenario. Several studies on how SARS-CoV-2 modulates the RAAS axis indicate that it alters our body's physiological balance. This review seeks to establish a hypothesis on the mechanical dependency of SARS-CoV-2 and RAAS modulation in the human body. This study intends to impart ideas on drug development and designing by targeting the modulation of the RAAS axis to inactivate the pathogenicity of the SARS-CoV-2 virus. A systematic hypothesis can severely attenuate the pathogenicity of the dreadful viruses of the future.

Altered microRNA Transcriptome in Cultured Human Airway Cells upon Infection with SARS-CoV-2.

Numerous proteomic and transcriptomic studies have been carried out to better understand the current multi-variant SARS-CoV-2 virus mechanisms of action and effects. However, they are mostly centered on mRNAs and proteins. The effect of the virus on human post-transcriptional regulatory agents such as microRNAs (miRNAs), which are involved in the regulation of 60% of human gene activity, remains poorly explored. Similar to research we have previously undertaken with other viruses such as Ebola and HIV, in this study we investigated the miRNA profile of lung epithelial cells following infection with SARS-CoV-2. At the 24 and 72 h post-infection time points, SARS-CoV-2 did not drastically alter the miRNome. About 90% of the miRNAs remained non-differentially expressed. The results revealed that miR-1246, miR-1290 and miR-4728-5p were the most upregulated over time. miR-196b-5p and miR-196a-5p were the most downregulated at 24 h, whereas at 72 h, miR-3924, miR-30e-5p and miR-145-3p showed the highest level of downregulation. In the top significantly enriched KEGG pathways of genes targeted by differentially expressed miRNAs we found, among others, MAPK, RAS, P13K-Akt and renin secretion signaling pathways. Using RT-qPCR, we also showed that SARS-CoV-2 may regulate several predicted host mRNA targets involved in the entry of the virus into host cells (ACE2, TMPRSS2, ADAM17, FURIN), renin-angiotensin system (RAS) (Renin, Angiotensinogen, ACE), innate immune response (IL-6, IFN1ß, CXCL10, SOCS4) and fundamental cellular processes (AKT, NOTCH, WNT). Finally, we demonstrated by dual-luciferase assay a direct interaction between miR-1246 and ACE-2 mRNA. This study highlights the modulatory role of miRNAs in the pathogenesis of SARS-CoV-2.

The alternative renin-angiotensin-system (RAS) signalling pathway in prostate cancer and its link to the current COVID-19 pandemic.

BACKGROUND: The renin-angiotensin system is known to maintain blood pressure and body fluids. However, it has been found to consist of at least two major constituents, the classic and the alternative pathway, balancing and supporting each other's signalling in a very intricate way. Current research has shown that the renin-angiotensin system is involved in a broad range of biological processes and diseases, such as cancer and infectious diseases. METHODS AND RESULTS: We conducted a literature review on the interaction of the renin-angiotensin system and prostate cancer and explored the research on the possible impact of the SARS-CoV-2 virus in this context. This review provides an update on contemporary knowledge into the alternative renin-angiotensin system, its role in cancer, specifically prostate cancer, and the implications of the current COVID-19 pandemic on cancer and cancer care. CONCLUSION: In this work, we aim to demonstrate how shifting the RAS signalling pathway from the classic to the alternative axis seems to be a viable option in supporting treatment of specific cancers and at the same time demonstrating beneficial properties in supportive care. It however seems to be the case that the infection with SARS-CoV-2 and subsequent impairment of the renin-angiotensin-system could exhibit serious deleterious long-term effects even in oncology.

The systemic renin-angiotensin system in COVID-19.

SARS-CoV-2 gains cell entry via angiotensin-converting enzyme (ACE) 2, a membrane-bound enzyme of the "alternative" (alt) renin-angiotensin system (RAS). ACE2 counteracts angiotensin II by converting it to potentially protective angiotensin 1-7. Using mass spectrometry, we assessed key metabolites of the classical RAS (angiotensins I-II) and alt-RAS (angiotensins 1-7 and 1-5) pathways as well as ACE and ACE2 concentrations in 159 patients hospitalized with COVID-19, stratified by disease severity (severe, n = 76; non-severe: n = 83). Plasma renin activity (PRA-S) was calculated as the sum of RAS metabolites. We estimated ACE activity using the angiotensin II:I ratio (ACE-S) and estimated systemic alt-RAS activation using the ratio of alt-RAS axis metabolites to PRA-S (ALT-S). We applied mixed linear models to assess how PRA-S and ACE/ACE2 concentrations affected ALT-S, ACE-S, and angiotensins II and 1-7. Median angiotensin I and II levels were higher with severe versus non-severe COVID-19 (angiotensin I: 86 versus 30 pmol/L, p < 0.01; angiotensin II: 114 versus 58 pmol/L, p < 0.05), demonstrating activation of classical RAS. The difference disappeared with analysis limited to patients not taking a RAS inhibitor (angiotensin I: 40 versus 31 pmol/L, p = 0.251; angiotensin II: 76 versus 99 pmol/L, p = 0.833). ALT-S in severe COVID-19 increased with time (days 1-6: 0.12; days 11-16: 0.22) and correlated with ACE2 concentration (r = 0.831). ACE-S was lower in severe versus non-severe COVID-19 (1.6 versus 2.6; p < 0.001), but ACE concentrations were similar between groups and correlated weakly with ACE-S (r = 0.232). ACE2 and ACE-S trajectories in severe COVID-19, however, did not differ between survivors and non-survivors. Overall RAS alteration in severe COVID-19 resembled severity of disease-matched patients with influenza. In mixed linear models, renin activity most strongly predicted angiotensin II and 1-7 levels. ACE2 also predicted angiotensin 1-7 levels and ALT-S. No single factor or the combined model, however, could fully explain ACE-S. ACE2 and ACE-S trajectories in severe COVID-19 did not differ between survivors and non-survivors. In conclusion, angiotensin II was elevated in severe COVID-19 but was markedly influenced by RAS inhibitors and driven by overall RAS activation. ACE-S was significantly lower with severe COVID-19 and did not correlate with ACE concentrations. A shift to the alt-RAS axis because of increased ACE2 could partially explain the relative reduction in angiotensin II levels.

Global distribution of ACE1 (rs4646994) and ACE2 (rs2285666) polymorphisms associated with COVID-19: A systematic review and meta-analysis.

BACKGROUND: Recent studies emphasize the significant impact of the renin-angiotensin aldosterone system (RAAS) as a risk factor associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, according to the literature, the effect of rs4646994 and rs2285666 polymorphisms on susceptibility and progression to severe clinical outcomes is still controversial. Our aim was to investigate the effect of polymorphisms such as rs4646994 and rs2285666 on susceptibility to coronavirus disease-2019 (COVID-19). METHODS: We conducted a comprehensive literature search using databases such as ISI Web of Science, PubMed, Scopus, and Google Scholar to retrieve studies on the effect of two polymorphisms (rs4646994 and rs2285666) of the angiotensin-converting enzyme (ACE) gene on COVID-19. Finally, the effect of each polymorphism on SARS-CoV-2 infection was measured based on the odds ratio with 95% confidence intervals. RESULTS: Analysis of the rs4646994 polymorphism showed that the frequency of the D allele in patients infected with COVID-19 was higher than that the I allele. Moreover, the authors found that the DD genotype increased the risk of severe disease by 1.7-fold in Asian population, whereas, this was not the case in the Western population. However, the rs4646994 II genotype plays a protective role against COVID-19 in Western countries. In the case of the rs2285666 polymorphism based on patient ethnicity, the C allele had the highest frequency. Interestingly, in people harboring the GG and TT genotypes, the risk of progression to severe disease significantly increased, while people with genotypes such as GA, AA and CC seem to be more resistant to severe Covid-19. CONCLUSIONS: Based on geographical region, the rs4646994 DD genotype may be considered as a predictive biomarker to identify the susceptibility of human to SARS-CoV-2 infection and severe COVID-19 outcomes. We also concluded that individuals with GG and TT genotypes are significantly more susceptible to severe outcomes of disease, while conversely, individuals with GA, AA, and CC genotypes are less susceptible to severe COVID-19.

Acute vaping in a golden Syrian hamster causes inflammatory response transcriptomic changes.

E-cigarette vaping is a major aspect of nicotine consumption, especially for children and young adults. Although it is branded as a safer alternative to cigarette smoking, murine and rat models of subacute and chronic e-cigarette vaping exposure have shown many proinflammatory changes in the respiratory tract. An acute vaping exposure paradigm has not been demonstrated in the golden Syrian hamster, and the hamster is a readily available small animal model that has the unique benefit of becoming infected with and transmitting respiratory viruses, including SARS-CoV-2, without genetic alteration of the animal or virus. Using a 2-day, whole body vaping exposure protocol in male golden Syrian hamsters, we evaluated serum cotinine, bronchoalveolar lavage cells, lung, and nasal histopathology, and gene expression in the nasopharynx and lung through reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Depending on the presence of nonnormality or outliers, statistical analysis was performed by ANOVA or Kruskal-Wallis tests. For tests that were statistically significant (P < 0.05), post hoc Tukey-Kramer and Dunn's tests, respectively, were performed to make pairwise comparisons between groups. In nasal tissue, RT-qPCR analysis revealed nicotine-dependent increases in gene expression associated with type 1 inflammation (CCL-5 and CXCL-10), fibrosis [transforming growth factor-ß (TGF-ß)], nicotine-independent increase oxidative stress response (SOD-2), and a nicotine-independent decrease in vasculogenesis/angiogenesis (VEGF-A). In the lung, nicotine-dependent increases in the expression of genes involved in the renin-angiotensin pathway [angiotensin-converting enzyme (ACE), ACE2], coagulation (tissue factor, Serpine-1), extracellular matrix remodeling (MMP-2, MMP-9), type 1 inflammation (IL-1ß, TNF-α, and CXCL-10), fibrosis (TGF-ß and Serpine-1), oxidative stress response (SOD-2), neutrophil extracellular traps release (ELANE), and vasculogenesis and angiogenesis (VEGF-A) were identified. To our knowledge, this is the first demonstration that the Syrian hamster is a viable model of e-cigarette vaping. In addition, this is the first report that e-cigarette vaping with nicotine can increase tissue factor gene expression in the lung. Our results show that even an acute exposure to e-cigarette vaping causes significant upregulation of mRNAs in the respiratory tract from pathways involving the renin-angiotensin system, coagulation, extracellular matrix remodeling, type 1 inflammation, fibrosis, oxidative stress response, neutrophil extracellular trap release (NETosis), vasculogenesis, and angiogenesis.

Renin-Angiotensin Aldosterone System Inhibitors and COVID-19: A Systematic Review and Meta-Analysis Revealing Critical Bias Across a Body of Observational Research.

Background Renin-angiotensin aldosterone system (RAAS) inhibitor-COVID-19 studies, observational in design, appear to use biased methods that can distort the interaction between RAAS inhibitor use and COVID-19 risk. This study assessed the extent of bias in that research and reevaluated RAAS inhibitor-COVID-19 associations in studies without critical risk of bias. Methods and Results Searches were performed in MEDLINE, EMBASE, and CINAHL databases (December 1, 2019 to October 21, 2021) identifying studies that compared the risk of infection and/or severe COVID-19 outcomes between those using or not using RAAS inhibitors (ie, angiotensin-converting enzyme inhibitors or angiotensin II type-I receptor blockers). Weighted hazard ratios (HR) and 95% CIs were extracted and pooled in fixed-effects meta-analyses, only from studies without critical risk of bias that assessed severe COVID-19 outcomes. Of 169 relevant studies, 164 had critical risks of bias and were excluded. Ultimately, only two studies presented data relevant to the meta-analysis. In 1 351 633 people with uncomplicated hypertension using a RAAS inhibitor, calcium channel blocker, or thiazide diuretic in monotherapy, the risk of hospitalization (angiotensin-converting enzyme inhibitor: HR, 0.76; 95% CI, 0.66-0.87; P<0.001; angiotensin II type-I receptor blockers: HR, 0.86; 95% CI, 0.77-0.97; P=0.015) and intubation or death (angiotensin-converting enzyme inhibitor: HR, 0.64; 95% CI, 0.48-0.85; P=0.002; angiotensin II type-I receptor blockers: HR, 0.74; 95% CI, 0.58-0.95; P=0.019) with COVID-19 was lower in those using a RAAS inhibitor. However, these protective effects are probably not clinically relevant. Conclusions This study reveals the critical risk of bias that exists across almost an entire body of COVID-19 research, raising an important question: Were research methods and/or peer-review processes temporarily weakened during the surge of COVID-19 research or is this lack of rigor a systemic problem that also exists outside pandemic-based research? Registration URL: www.crd.york.ac.uk/prospero/; Unique identifier: CRD42021237859.

Development of an aerosol intervention for COVID-19 disease: Tolerability of soluble ACE2 (APN01) administered via nebulizer.

As ACE2 is the critical SARS-CoV-2 receptor, we hypothesized that aerosol administration of clinical grade soluble human recombinant ACE2 (APN01) will neutralize SARS-CoV-2 in the airways, limit spread of infection in the lung, and mitigate lung damage caused by deregulated signaling in the renin-angiotensin (RAS) and Kinin pathways. Here, after demonstrating in vitro neutralization of SARS-CoV-2 by APN01, and after obtaining preliminary evidence of its tolerability and preventive efficacy in a mouse model, we pursued development of an aerosol formulation. As a prerequisite to a clinical trial, we evaluated both virus binding activity and enzymatic activity for cleavage of Ang II following aerosolization. We report successful aerosolization for APN01, retaining viral binding as well as catalytic RAS activity. Dose range-finding and IND-enabling repeat-dose aerosol toxicology testing were conducted in dogs. Twice daily aerosol administration for two weeks at the maximum feasible concentration revealed no notable toxicities. Based on these results, a Phase I clinical trial in healthy volunteers has now been initiated (NCT05065645), with subsequent Phase II testing planned for individuals with SARS-CoV-2 infection.

Targeting and Modulation of the Natriuretic Peptide System in Covid-19: A Single or Double-Edged Effect?

Natriuretic peptide system (NPS) is a group of peptide hormones or paracrine factors, including atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and natriuretic peptide precursor C (NPC), that are structurally related. The physiological effects of NPS include natriuresis, increased glomerular filtration rate, inhibition release of renin, vasopressin, and aldosterone, sympathetic inhibition, vasodilatations, and prevents cardiac hypertrophy and remodeling. ANP has immunological effects, as it is produced locally from immune cells; it regulates innate and adaptive immune responses. Metabolism and degradation of ANP are achieved by neutral endopeptidase (NEP), also known as neprilysin. Coronavirus disease 2019 (Covid-19) pandemic may lead to acute lung injury (ALI) and/or respiratory distress syndrome (ARDS). The underlying causes of inflammatory and immunological disorders in patients with severe Covid-19 are connected to the immune over-stimulation with the subsequent release of pro-inflammatory cytokines. Covid-19 severity is linked with high ANP serum levels regardless of acute cardiac injury. Inflammatory stimuli appear to be linked with the release of NPs, which anti-inflammatory effects prevent the development of ALI/ARDS in Covid-19. Therefore, neprilysin inhibitors like sacubitril increase endogenous NPs and may reduce the risk of ALI in Covid-19 due to the potentiation of endogenous anti-inflammatory effects of NPs. However, sacubitril increases gastrin-releasing peptide, cathepsin G and release of pro-inflammatory cytokines that are inactivated by neprilysin. In conclusion, NPs and neprilysin have cardio-pulmonary protective effects against Covid-19-induced ALI/ARDS. Neprilysin inhibitor sacubitril has dual protective and harmful effects regarding metabolizing vasoactive peptides by neprilysin. These findings require potential reevaluation of the effect of neprilysin inhibitors in managing Covid-19.

Impact of the withdrawal of renin-angiotensin-aldosterone inhibitors on mortality in COVID-19 patients.

Background: Chronic use of Angiotensin-converting enzyme (ACE) inhibitors (ACEi) and aldosterone-receptor blockers (ARB) is not associated with worse outcomes in patients with COVID-19. However, evidence on the impact of their discontinuation during hospital admission is scarce. Our aim was to determine whether withdrawal of ACEi, ARB and mineralocorticoid receptor antagonists (MRA) is associated with all-cause mortality in a real-life large cohort of patients with SARS-CoV-2 infection. Methods: Observational cohort study from a large referral center from 1 March 2020 to 20 April 2020. Withdrawal of renin-angiotensin-aldosterone system inhibitors was defined as the absence of any received dose during hospital admission in patients receiving chronic treatment. Prescriptions during admission were confirmed by data from the central pharmacy computerized system. Results: A total of 2042 patients (mean age 68.4±17.6, 57.1% male) with confirmed COVID-19 were included. During a median follow-up of 57 (21-55) days, 583 (28.6%) died. Prior to hospital admission 468 (22.9%), 343 (16.8%) and 83 (4.1%) patients were receiving ACEi, ARB and MRA respectively. During the study period, 216 (46.2%), 193 (56.3%) and 41 (49.4%) were withdrawn from the corresponding drug. After adjusting for age, cardiovascular risk factors, baseline comorbidities and in-hospital COVID-19 dedicated treatment, withdrawal of ACE inhibitors (hazard ration [HR] 1.48 [95% confidence interval -CI- 1.16-1.89]) and MRA (HR 2.01 [95% CI 1.30-3.10]) were shown to be independent predictors of all-cause mortality. No independent relationship between ARB withdrawal and mortality was observed. Conclusion: ACEi and MRA withdrawal were associated with higher mortality. Strong consideration should be given to not discontinuing these medications during hospital admission.

Introdução: O uso crónico de inibidores da ECA (IECA) e de antagonistas dos recetores de aldosterona (ARA) não está associado a resultados piores em doentes com Covid-19. No entanto, a evidência relativa ao impacto da sua retirada durante a admissão hospitalar é escassa. O nosso objetivo foi determinar se a retirada do IECA, ARA e antagonistas dos recetores dos mineralocorticóides (ARM) está associada à mortalidade por todas as causas numa grande coorte real de doentes com infeção por SRA-CoV-2. Métodos: Estudo coorte observacional a partir de um grande centro de referência de 1 de março de 2020 a 20 de abril de 2020. A retirada dos inibidores do sistema RAAS foi definida como a ausência de qualquer dose recebida durante a admissão hospitalar em doentes que recebem tratamento prolongado. As prescrições durante a admissão foram confirmadas por dados do sistema informático da farmácia central. Resultados: Um total de 2042 doentes (idade média de 68,4 ±17,6, 57,1% do sexo masculino) com COVID-19 confirmado foram incluídos. Durante um acompanhamento médio de 57 (21-55) dias, 583 (28,6%) morreram. Conclusão: A retirada do IECA e do ARM foi associada a uma mortalidade mais elevada. Deve ser dada grande atenção para não interromper estes medicamentos durante a admissão hospitalar.

Kidney Angiotensin in Cardiovascular Disease: Formation and Drug Targeting.

The concept of local formation of angiotensin II in the kidney has changed over the last 10-15 years. Local synthesis of angiotensinogen in the proximal tubule has been proposed, combined with prorenin synthesis in the collecting duct. Binding of prorenin via the so-called (pro)renin receptor has been introduced, as well as megalin-mediated uptake of filtered plasma-derived renin-angiotensin system (RAS) components. Moreover, angiotensin metabolites other than angiotensin II [notably angiotensin-(1-7)] exist, and angiotensins exert their effects via three different receptors, of which angiotensin II type 2 and Mas receptors are considered renoprotective, possibly in a sex-specific manner, whereas angiotensin II type 1 (AT1) receptors are believed to be deleterious. Additionally, internalized angiotensin II may stimulate intracellular receptors. Angiotensin-converting enzyme 2 (ACE2) not only generates angiotensin-(1-7) but also acts as coronavirus receptor. Multiple, if not all, cardiovascular diseases involve the kidney RAS, with renal AT1 receptors often being claimed to exert a crucial role. Urinary RAS component levels, depending on filtration, reabsorption, and local release, are believed to reflect renal RAS activity. Finally, both existing drugs (RAS inhibitors, cyclooxygenase inhibitors) and novel drugs (angiotensin receptor/neprilysin inhibitors, sodium-glucose cotransporter-2 inhibitors, soluble ACE2) affect renal angiotensin formation, thereby displaying cardiovascular efficacy. Particular in the case of the latter three, an important question is to what degree they induce renoprotection (e.g., in a renal RAS-dependent manner). This review provides a unifying view, explaining not only how kidney angiotensin formation occurs and how it is affected by drugs but also why drugs are renoprotective when altering the renal RAS. SIGNIFICANCE STATEMENT: Angiotensin formation in the kidney is widely accepted but little understood, and multiple, often contrasting concepts have been put forward over the last two decades. This paper offers a unifying view, simultaneously explaining how existing and novel drugs exert renoprotection by interfering with kidney angiotensin formation.

Cross-Talk between the (Endo)Cannabinoid and Renin-Angiotensin Systems: Basic Evidence and Potential Therapeutic Significance.

This review is dedicated to the cross-talk between the (endo)cannabinoid and renin angiotensin systems (RAS). Activation of AT1 receptors (AT1Rs) by angiotensin II (Ang II) can release endocannabinoids that, by acting at cannabinoid CB1 receptors (CB1Rs), modify the response to AT1R stimulation. CB1R blockade may enhance AT1R-mediated responses (mainly vasoconstrictor effects) or reduce them (mainly central nervous system-mediated effects). The final effects depend on whether stimulation of CB1Rs and AT1Rs induces opposite or the same effects. Second, CB1R blockade may diminish AT1R levels. Third, phytocannabinoids modulate angiotensin-converting enzyme-2. Additional studies are required to clarify (1) the existence of a cross-talk between the protective axis of the RAS (Ang II-AT2 receptor system or angiotensin 1-7-Mas receptor system) with components of the endocannabinoid system, (2) the influence of Ang II on constituents of the endocannabinoid system and (3) the (patho)physiological significance of AT1R-CB1R heteromerization. As a therapeutic consequence, CB1R antagonists may influence effects elicited by the activation or blockade of the RAS; phytocannabinoids may be useful as adjuvant therapy against COVID-19; single drugs acting on the (endo)cannabinoid system (cannabidiol) and the RAS (telmisartan) may show pharmacokinetic interactions since they are substrates of the same metabolizing enzyme of the transport mechanism.

Association of Renin-Angiotensin-Aldosterone Inhibitors with COVID-19 Infection and Disease Severity among Individuals with Hypertension.

BACKGROUND: The association between use of renin-angiotensin-aldosterone (RAAS) inhibitors and both SARS-CoV-2 infection and the development of severe COVID-19 has been presented in the recent medical literature with inconsistent results. OBJECTIVES: To assess the association between RAAS inhibitor use and two outcomes: infection with SARS-CoV-2 (Model 1) and severe COVID-19 among those infected (Model 2). METHODS: We accessed used electronic health records of individuals from Israel who were receiving anti-hypertensive medications for this retrospective study. For Model 1 we used a case-control design. For Model 2 we used a cohort design. In both models, inverse probability weighting adjusted for identified confounders as part of doubly robust outcome regression. RESULTS: We tested 38,554 individuals for SARS-CoV-2 who had hypertension and were being treated with medication; 691 had a positive test result. Among those with a positive test, 119 developed severe illness. There was no association between RAAS inhibitor use and a positive test. Use of RAAS inhibitors was associated with a decreased risk for severe COVID-19 (adjusted odds ratio [OR] 0.47, 95% confidence interval [95%CI] 0.29-0.77) compared with users of non-RAAS anti-hypertensive medication. The association remained significant when use of angiotensin-converting-enzyme inhibitors (adjusted OR 0.46, 95%CI 0.27-0.77) and angiotensin II receptor blockers (adjusted OR 0.39, 95%CI 0.16-0.95) were analyzed separately. CONCLUSIONS: Among individuals with hypertension using RAAS inhibitors, we found a lower risk of severe disease compared to those using non-RAAS anti-hypertensive medications. This finding suggests that RAAS inhibitors may have a protective effect on COVID-19 severity among individuals with medically treated hypertension.

Covid-19 associated reduction in hypertension-related diagnostic and therapeutic procedures in Excellence Centers of the European Society of Hypertension.

BACKGROUND: The Covid-19 pandemic necessitated a decrease in non-Covid-19 related diagnostic and therapeutic procedures in many countries. We explored the impact on tertiary hypertension care. METHODS: We conducted an electronic survey regarding 6 key procedures in hypertension care within the Excellence Center network of the European Society of Hypertension. RESULTS: Overall, 54 Excellence Centers from 18 European and 3 non-European countries participated. From 2019 to 2020, there were significant decreases in the median number per centre of ambulatory blood pressure monitorings (ABPM: 544/289 for 2019/2020), duplex ultrasound of renal arteries (Duplex RA: 88.5/55), computed tomographic/magnetic resonance imaging angiography of renal arteries (CT/MRI RA: 66/19.5), percutaneous angioplasties of renal arteries (PTA RA: 5/1), laboratory tests for catecholamines (116/67.5) and for renin/aldosterone (146/83.5) (p < 0.001 for all comparisons, respectively). While reductions in all assessed diagnostic and therapeutic procedures were observed in all annual 3-months periods in the comparisons between 2019 and 2020, the most pronounced reduction occurred between April and June 2020, which was the period of the first wave and the first lockdown in most affected countries. In this period, the median reductions in 2020, as compared to 2019, were 50.7% (ABPM), 47.1% (Duplex RA), 50% (CT/MRI RA), 57.1% (PTA RA), 46.9% (catecholamines) and 41.0% (renin/aldosterone), respectively. Overall differences in reduction between 3-month time intervals were statistically highly significant. CONCLUSION: Diagnostic and therapeutic procedures related to hypertension were dramatically reduced during the first year of the Covid-19 pandemic, with the largest reduction during the first lockdown. The long-term consequences regarding blood pressure control and, ultimately, cardiovascular events remain to be investigated.

Single-Cell Transcriptome Analysis Reveals the Role of Pancreatic Secretome in COVID-19 Associated Multi-organ Dysfunctions.

The SARS-CoV-2 infection affects the lungs, heart, kidney, intestine, olfactory epithelia, liver, and pancreas and brings forward multi-organ dysfunctions (MODs). However, mechanistic details of SARS-CoV-2-induced MODs are unclear. Here, we have investigated the role of pancreatic secretory proteins to mechanistically link COVID-19 with MODs using single-cell transcriptome analysis. Secretory proteins were identified using the Human Protein Atlas. Gene ontology, pathway, and disease enrichment analyses were used to highlight the role of upregulated pancreatic secretory proteins (secretome). We show that SARS-CoV-2 infection shifts the expression profile of pancreatic endocrine cells to acinar and ductal cell-specific profiles, resulting in increased expression of acinar and ductal cell-specific genes. Among all the secretory proteins, the upregulated expression of IL1B, AGT, ALB, SPP1, CRP, SERPINA1, C3, TFRC, TNFSF10, and MIF was mainly associated with disease of diverse organs. Extensive literature and experimental evidence are used to validate the association of the upregulated pancreatic secretome with the coagulation cascade, complement activation, renin-angiotensinogen system dysregulation, endothelial cell injury and thrombosis, immune system dysregulation, and fibrosis. Our finding suggests the influence of an upregulated secretome on multi-organ systems such as nervous, cardiovascular, immune, digestive, and urogenital systems. Our study provides evidence that an upregulated pancreatic secretome is a possible cause of SARS-CoV-2-induced MODs. This finding may have a significant impact on the clinical setting regarding the prevention of SARS-CoV-2-induced MODs.

Associastion of In-hospital Use of Statins, Aspirin, and Renin-Angiotensin-Aldosterone Inhibitors with Mortality and ICU Admission Due to COVID-19.

The exaggerated host response to Sars-CoV-2 plays an important role in COVID-19 pathology but provides a therapeutic opportunity until definitive virus targeted therapies and vaccines become available. Given a central role of endothelial dysfunction and systemic inflammation, repurposing ACE inhibitors (ACEIs), angiotensin receptor blockers (ARBs), statins, and aspirin has been of interest. In this retrospective, single-center study, we evaluated the primary outcomes of mortality and ICU admission in 587 hospitalized patients with documented COVID-19 with or without ACEIs, ARBs, statins, and aspirin. Atorvastatin was associated with reduced mortality, which persisted after adjusting for age, lockdown status, and other medications (OR: 0.18. 95% CI: 0.06-0.49, P = 0.001). ACEIs were also associated with reduced mortality in the crude model (OR: 0.20, CI: 0.06-0.66, P = 0.008), as ACEIs and ARBs were combined as a single group (OR: 0.35, CI: 0.16-0.75, P = 0.007), although ARBs alone did not reach statistical significance. There was no association between any medications and risk of ICU admission. Aspirin only achieved a significant association of reduced mortality in a subgroup of patients with diabetes in the crude model (OR: 0.17, CI: 0.04-0.80, P = 0.02). The reduced mortality observed with atorvastatin is consistent with other literature, and consideration should be given to atorvastatin as a COVID-19 treatment. While there was suggested benefit of ACEIs and ARBs in the present study, other studies are varied and further studies are warranted to recommend employing these medications as a treatment strategy. Nevertheless, this study combined with others continues to give credibility that ACEIs and ARBs are safe to continue in the setting of COVID-19.