Angiotensin-converting Enzyme Research Articles

Molecular mechanisms of thalidomide effectiveness on COVID-19 patients explained: ACE2 is a new ΔNp63α target gene

COVID-19 pandemic is caused by the SARS-CoV-2 virus, whose internalization and infection are mediated by the angiotensin-converting enzyme 2 (ACE2). The identification of novel approaches to tackle this step is instrumental for the development of therapies for the management of COVID-19 and other diseases with a similar mechanism of infection. Thalidomide, a drug sadly known for its teratogenic effects, has potent immunomodulatory and anti-inflammatory properties. Treatment with this drug has been shown to improve the immune functions of COVID-19 patients and proposed for the management of COVID-19 in clinical practice through drug repositioning. Here, we investigated the molecular details linking thalidomide to ACE2 and COVID-19, showing that in conditions mimicking SARS-CoV-2-associated cytokine storm, the transcription factor ΔNp63α and ACE2 are stabilized, and IL-8 production is increased. In such conditions, we found p63 to bind to and regulate the expression of the ACE2 gene. We previously showed that ΔNp63α is degraded upon thalidomide treatment and now found that treatment with this drug—or with its analogue lenalidomide—downregulates ACE2 in a p63-dependent manner. Finally, we found that thalidomide treatment reduces in vitro infection by pseudo-SARS-CoV-2, a baculovirus pseudotyped with the SARS-CoV-2 spike protein. Overall, we propose the dual effect of thalidomide in reducing SARS-CoV-2 viral re-entry and inflammation through p63 degradation to weaken SARS-CoV-2 entry into host cells and mitigate lung inflammation, making it a valuable option in clinical management of COVID-19.Key messagesThalidomide treatment results in p63-dependent ACE2 downregulation.ACE2 is a p63 transcriptional target.Thalidomide reduces the “cytokine storm” associated to COVID-19.Thalidomide prevents viral re-entry of SARS-CoV-2 by p63-dependent ACE2 downregulation.Thalidomide is a modulator of SARS-CoV-2 or other ACE2-dependent infections.ACE2 is modulated by a pharmacological substance.

Harringtonine metabolites: 5'-de-O-methylharringtonine and cephalotaxine, targeting spike protein and TMPRSS2 to double block membrane fusion of SARS-CoV-2 and its variants

Membrane fusion is the main pathway for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to invade host cells. Harringtonine (HT), derived from cephalotaxus fortunei Hook. f., has been recognized as an effective antagonist of SARS-CoV-2. It can directly block the active binding of spike (S) protein to host angiotensin converting enzyme 2 (ACE2), as well as hinder the enzymolysis of transmembrane serine proteases 2 (TMPRSS2). This study examined the potential of HT metabolites, 5'-de-O-methylharringtonine and cephalotaxine, as the membrane fusion inhibitors for SARS-CoV-2. 5'-De-O-methylharringtonine was synthesized and subsequently characterized by high resolution mass spectrometry and nuclear magnetic resonance to be structurally consistent, with a purity of 92.677% determined by reverse phase high performance liquid chromatography. Both 5'-de-O-methylharringtonine and cephalotaxine can specifically bind to SARS-CoV-2 S protein and TMPRSS2 using cell membrane chromatography. They can form hydrogen bonds with key sites that correlated highly with the enhanced binding affinity of SARS-CoV-2 and its variants to ACE2 or nafamostat to TMPRSS2. Moreover, 5'-de-O-methylharringtonine and cephalotaxine can inhibit pseudotyped virus entry and membrane fusion in a dose-dependent manner, with enhanced effectiveness upon elevated expression of TMPRSS2. Importantly, they displayed low cytotoxic effects on human normal cell lines. Our study suggested that 5'-de-O-methylharringtonine and cephalotaxine were of low toxicity and safety for humans as potential antagonists of SARS-CoV-2 and its variants, which deserve further validation in a biosafety level 3 facility.

Walnut peptide relieves hypertension and associated kidney and heart injury by regulating the renin-angiotensin-aldosterone system and intestinal microbiota.

Hypertension is a chronic disease with high morbidity and mortality. Previously, we screened a walnut meal peptide FDWLR (PEP) with significant angiotensin-converting enzyme inhibitory activity. The present study further investigated the anti-hypertensive effects of PEP in vivo using spontaneously hypertensive rats. The results indicated that PEP reduced blood pressure and the indices in the renin-angiotensin-aldosterone system (RAAS) including angiotensin-converting enzyme (ACE) (decreased by 15.36%), angiotensin II (Ang II) (decreased by 31.56%), angiotensinogen (AGT) (decreased by 58.84%) and aldosterone (ALD) (decreased by 18.27%), whereas NO levels increased by 54.96%. The pathological analysis showed that PEP relieved cardiac and renal damage. PEP also alleviated oxidative stress, inflammation and fibrosis in the heart and kidney. Mechanistically, PEP mitigated cardiac and renal damage by simultaneously regulating ACE-Ang II-AT1R and the ACE2-Ang (1-7)-MAS axis. Additionally, PEP increased the levels of short chain fatty acids by 224.16% and improved gut microbiota by increasing the abundance of Prevotella, Phascolarctobacterium, Clostridium_sensu_stricto and Bifidobacterium, at the same time as decreasing Bacteroides and Alistipes abundances. This study indicated that PEP prevented hypertension and associated heart and kidney damage by modulating the RAAS system and gut microbiota, which is valuable in guiding future development and optimal utilization of walnut meal. © 2024 Society of Chemical Industry.

Reduction of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant infection by blocking the epidermal growth factor receptor (EGFR) pathway.

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants presents challenges in global efforts to transition from the pandemic to an endemic stage. The spike protein of the SARS-CoV-2 virus, which is pivotal for cell entry, exhibits significant mutations in its variants, potentially affecting infectivity and therapeutic efficacy. Recent findings indicate upregulation of the epidermal growth factor receptor (EGFR) pathway, a key target in cancer therapy, by the spike protein of SARS-CoV-2. This study aimed to investigate the activity of the EGFR pathway against SARS-CoV-2 variants and to assess the inhibitory effects of EGFR inhibitors using SARS-CoV variant pseudoviral particles to guide future therapeutic strategies. Omicron variant SARS-CoV pseudoviral particles exhibited heightened infectivity in human angiotensin-converting enzyme 2 (hACE2)-expressing HEK293 and A549 lung cancer cells accompanied by increased EGFR pathway activation in infected cells. Using the EGFR tyrosine kinase inhibitor, osimertinib, we observed a reduction in viral infection rates in hACE2-HEK293 and A549 cells infected with the SARS-CoV-2 variant pseudoviral particles. We conducted further experiments to confirm that the reduction in infection efficacy with osimertinib treatment was not associated to a decrease in cell viability. Furthermore, this inhibitory effect of osimertinib in cell lines was corroborated in a spheroid cell culture model derived from hACE2-A549 cells. These findings suggest the potential application of EGFR-targeted antiviral therapy against highly infectious SARS-CoV-2 variants.IMPORTANCEThe emergence of novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants is concerning as vaccines designed for one variant need not essentially protect against other novel variants. Therefore, there is an urgent need to identify therapies that can act against multiple novel variants that have heightened virulence compared with the wild type. It has been reported that the spike protein of the SARS-CoV-2 virus elicits an increased expression of the epidermal growth factor receptor (EGFR) pathway. We used this information and examined whether treatment with an EGFR inhibitor, osimertinib, which is already approved for clinical use in cancer therapy, can reduce the infection caused by SARS-CoV-2, wild type, and Omicron and Delta variants, in two cell lines and one spheroid model. The results showed that osimertinib treatment successfully reduced infection efficacy, particularly in variants, and that this effect was not related to a reduction in cell viability, making this a promising strategy for treating SARS-CoV-2 infections.

In-Hospital Mortality and Treatment in Patients With Acute Coronary Syndrome With and Without Standard Modifiable Cardiovascular Risk Factors: Findings From the CCC-ACS Project.

Patients with acute coronary syndrome without standard modifiable cardiovascular risk factors (SMuRFs; hypertension, smoking, dyslipidemia, diabetes) have not been well studied, with little known about their characteristics, quality of care, or outcomes. We sought to systematically analyze patients with ACS without SMuRFs, especially to evaluate the effectiveness of guideline-directed medical therapy for these patients. In the CCC-ACS (Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome) project (2014-2019), we examined the presence and absence of SMuRFs and features among 89 462 patients with initial acute coronary syndrome. The main outcome was in-hospital all-cause mortality. Among eligible patients, 11.0% had none of the SMuRFs (SMuRF-less). SMuRF-less patients had higher in-hospital mortality (unadjusted hazard ratio [HR], 1.49 [95% CI, 1.19-1.87]). After adjustment for clinical characteristics and treatments, the associations between SMuRF status and in-hospital mortality persisted (adjusted HR, 1.35 [95% CI, 1.07-1.70]). Guideline-directed optimal medical therapy (receiving angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, β-blockers, and statins) was not associated with lower mortality (adjusted HR, 0.98 [95% CI, 0.58-1.67]) in SMuRF-less patients, unlike the association in patients with SMuRFs (adjusted HR, 0.80 [95% CI, 0.66-0.98]). Sensitivity analyses were consistent with these results. SMuRF-less patients were associated with an increased risk of in-hospital mortality. Guideline-directed medical therapy was less effective in SMuRF-less patients than in patients with SMuRFs. Dedicated studies are needed to confirm the optimal therapy for SMuRF-less patients. URL: https://www.clinicaltrials.gov; Unique identifier: NCT02306616.

Infiltrating monocytes drive cardiac dysfunction in a cardiomyocyte-restricted mouse model of SARS-CoV-2 infection.

Cardiovascular manifestations of coronavirus disease 2019 (COVID-19) include myocardial injury, heart failure, and myocarditis and are associated with long-term disability and mortality. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA and antigens are found in the myocardium of COVID-19 patients, and human cardiomyocytes are susceptible to infection in cell or organoid cultures. While these observations raise the possibility that cardiomyocyte infection may contribute to the cardiac sequelae of COVID-19, a causal relationship between cardiomyocyte infection and myocardial dysfunction and pathology has not been established. Here, we generated a mouse model of cardiomyocyte-restricted infection by selectively expressing human angiotensin-converting enzyme 2 (hACE2), the SARS-CoV-2 receptor, in cardiomyocytes. Inoculation of Myh6-Cre Rosa26loxP-STOP-loxP-hACE2 mice with an ancestral, non-mouse-adapted strain of SARS-CoV-2 resulted in viral replication within the heart, accumulation of macrophages, and moderate left ventricular (LV) systolic dysfunction. Cardiac pathology in this model was transient and resolved with viral clearance. Blockade of monocyte trafficking reduced macrophage accumulation, suppressed the development of LV systolic dysfunction, and promoted viral clearance in the heart. These findings establish a mouse model of SARS-CoV-2 cardiomyocyte infection that recapitulates features of cardiac dysfunctions of COVID-19 and suggests that both viral replication and resultant innate immune responses contribute to cardiac pathology.IMPORTANCEHeart involvement after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection occurs in multiple ways and is associated with worse outcomes in coronavirus disease 2019 (COVID-19) patients. It remains unclear if cardiac disease is driven by primary infection of the heart or immune response to the virus. SARS-CoV-2 is capable of entering contractile cells of the heart in a culture dish. However, it remains unclear how such infection affects the function of the heart in the body. Here, we designed a mouse in which only heart muscle cells can be infected with a SARS-CoV-2 strain to study cardiac infection in isolation from other organ systems. In our model, infected mice show viral infection, worse function, and accumulation of immune cells in the heart. A subset of immune cells facilitates such worsening heart function. As this model shows features similar to those observed in patients, it may be useful for understanding the heart disease that occurs as a part of COVID-19.

Dexamethasone, Remdesivir and Azithromycin modulate ACE2 and IL-6 in Lung Epithelial Cells.

The optimal use of steroids in COVID-19 patients remains challenging. Current S3-guidelines "Recommendations for patients with COVID-19" recommend dexamethasone (DEX) for patients requiring respiratory support, remdesivir (RD) in the early disease phase and azythromycin (AZ) is no longer recommended. We investigated effects of DEX, RD and AZ in a lipopolysaccharide induced inflammation in lung cells in vitro and analyzed publicly available datasets with a focus on the Angiotensin-converting enzyme 2 (ACE2) to better understand drugs' mechanisms of action. human bronchial (Calu) and alveolar (A549) lung epithelial cells were treated with DEX, AZ or RDV in the presence of lipopolysaccharides (LPS). Gene expression (GE) of ACE2, IL-6 and the IL-6 protein release were measured. Publicly available GE data from lung tissues of COVID-19 patients and from lung cells treated with DEX were analyzed for the GE of ACE2. DEX increased and RDV and AZ reduced the GE of ACE2 in LPS-stimulated bronchial and alveolar epithelial cells. Only DEX significantly reduced LPS-induced IL-6 releases in alveolar cells substantially. The database analyses showed an, albeit not always significant, increase in ACE2 for lung tissue or cell lines treated with DEX. Lung tissue from patients after COVID-19 infection as well as bronchial cell cultures after COVID-19 infection showed lower GEs of ACE2. DEX can increase ACE2 expression in vitro and thereby the portal of entry of SARS-CoV-2 into lung cells during an LPS induced inflammation. Simultaneously the inflammatory marker IL-6 is reduced. Comparative database analyses indicate that these processes can also take place in vivo.

Establishment of in-house assay for screening of anti-SARS-CoV-2 protein inhibitors

Developing a potent antiviral agent to combat Coronavirus Disease-19 (COVID-19) is of critical importance as we may be at risk of the emergence of new virus strains or another pandemic recurrence. The interaction between the SARS-CoV-2 spike protein and Angiotensin Converting Enzyme 2 (ACE2) is the main protein-protein interaction (PPI) implicated in the virus entry into the host cells. Spike-ACE2 PPI represents a major target for drug intervention. We have repurposed a previously described protein-protein interaction detection method to be utilized as a drug screening assay. The assay was standardized using Chitosan nanoparticles (CNPs) as the drug and SARS-CoV-2 spike-ACE2 interaction as the PPI model. The assay was then used to screen four natural bioactive compounds: Curcumin (Cur), Gallic acid (GA), Quercetin (Q), and Silymarin (Sil), and their cytotoxicity was evaluated in vitro. Production of the spike protein and the evaluation of its activity in comparison to a standard commercial protein was part of our work as well. Here we describe a novel simple immunofluorescent screening assay to identify potential SARS-CoV-2 inhibitors that could assess the inhibitory effect of any ligand against any PPI.Graphical

Bioactive Properties of Enzymatic Gelatin Hydrolysates Based on In Silico, In Vitro, and In Vivo Studies.

This current study aims to analyze the potential bioactivities possessed by the enzymatic hydrolysates of commercial bovine, porcine, and tilapia gelatins using bioinformatics in combination with in vitro and in vivo studies. The hydrolysate with superior inhibition of angiotensin converting enzyme (ACE) activity was used to treat the D-galactose (DG)-induced amnesic mice. In silico digestion of the gelatins led to the identification of peptide sequences with potential antioxidant, ACE-inhibitory, and anti-amnestic properties. The results of in vitro digestion revealed that the <1 kDa peptide fraction of porcine gelatin hydrolysate obtained after 1 h digestion with papain (PP) (PP1, <1 kDa) potently inhibited ACE, acetylcholinesterase, and prolyl endopeptidase activities at 87.42%, 21.24%, and 48.07%, respectively. Administering the PP1 to DG-induced amnesic mice ameliorated the spatial cognitive impairment and Morris water maze learning abilities. The dentate area morphology in the PP1-treated mice was relatively similar to the control group. In addition, PP1 enhanced the antioxidant capacity in the DG-induced amnesic mice. This study suggests that PP1 could serve as a potential treatment tool against oxidative stress, hypertension, and neurodegenerative diseases.

Effectiveness and risk of ARB and ACEi among different ethnic groups in England: A reference trial (ONTARGET) emulation analysis using UK Clinical Practice Research Datalink Aurum-linked data.

Guidelines by the National Institute for Health and Care Excellence recommend an angiotensin receptor blocker (ARB) rather than an angiotensin-converting enzyme inhibitor (ACEi) for the treatment of hypertension for people of African and Caribbean descent, due to an increased risk of angioedema associated with ACEi use observed in US trials. However, the effectiveness and risk of these drugs in Black populations in UK routine care is unknown. We applied a reference trial emulation approach to UK Clinical Practice Research Datalink Aurum data (linked with data from Hospital Episode Statistics and Office for National Statistics) to study the comparative effectiveness of ARB and ACEi in ethnic minority groups in England, after benchmarking results against the ONTARGET trial. Approximately 17,593 Black, 30,805 South Asian, and 524,623 White patients receiving a prescription for ARB/ACEi between 1 January 2001 and 31 July 2019 were included with a median follow-up of 5.2 years. The primary composite outcome was cardiovascular-related death, myocardial infarction, stroke, or hospitalisation for heart failure with individual components studied as secondary outcomes. Angioedema was a safety endpoint. We assessed outcomes using an inverse-probability-weighted Cox proportional hazards model for ARB versus ACEi with heterogeneity by ethnicity assessed on the relative and absolute scale. For the primary outcome, 27,327 (18.0%) events were recorded in the ARB group (event rate: 25% per 5.5 person-years) and 80,624 (19.1%) events (event rate: 26% per 5.5 person-years) in the ACEi group. We benchmarked results against ONTARGET and observed hazard ratio (HR) 0.96 (95% CI: 0.95, 0.98) for the primary outcome, with an absolute incidence rate difference (IRD)% of -1.01 (95% CI: -1.42, -0.60) per 5.5 person-years. We found no evidence of treatment effect heterogeneity by ethnicity for the primary outcome on the multiplicative (Pint = 0.422) or additive scale (Pint = 0.287). Results were consistent for most secondary outcomes. However, for cardiovascular-related death, which occurred in 37,554 (6.6%) people, there was strong evidence of heterogeneity on the multiplicative (Pint = 0.002) and additive scale (Pint < 0.001). Compared to ACEi, ARB were associated with more events in Black individuals (HR 1.20 (95% CI: 1.02, 1.40); IRD% 1.07 (95% CI: 0.10, 2.04); number-needed-to-harm (NNH): 93) and associated with fewer events in White individuals (HR 0.91 (95% CI: 0.88, 0.93); IRD% -0.87 (95% CI: -1.10, -0.63); number-needed-to-treat (NNT): 115), and no differences in South Asian individuals (HR 0.97 (95% CI: 0.86, 1.09); IRD% -0.17 (95% CI: -0.87, 0.53)). For angioedema, HR 0.56 (95% CI: 0.46, 0.67) with no heterogeneity for ARB versus ACEi on the multiplicative scale (Pint = 0.306). However, there was heterogeneity on the additive scale (Pint = 0.023). Absolute risks were higher in Black individuals (IRD% -0.49 (95% CI: -0.79, -0.18); NNT: 204) compared with White individuals (IRD% -0.06 (95% CI: -0.09, -0.03); NNT: 1667) and no difference among South Asian individuals (IRD% -0.05 (95% CI: -0.15, 0.05) for ARB versus ACEi. These results demonstrate variation in drug effects of ACEi and ARB for some outcomes by ethnicity and suggest the potential for adverse consequences from current UK guideline recommendations for ARB in preference to ACEi for Black individuals.

Association of Angiotensin Converting Enzyme (insertion\deletion) and Angiotensin II Type 1 Receptor (A1166C) gene polymorphisms with diabetic nephropathy in Iraqi type 2 diabetic patients

Renin-angiotensin-aldosterone system abnormalities are the most prevalent cause of renal hemodynamic abnormalities, and candidate genes in this system are involved in the etiology of diabetic nephropathy (DN). A polymorphism in the angiotensin converting enzyme (ACE) gene I(insertion)\D(deletion) has been correlated to plasma ACE levels. Furthermore, the Angiotensin II Type 1 Receptor AGT1R (A1166C) expression pattern is highly related to nephropathy. The objectives of this study involved evaluating the frequency of the ACE (I/D) and AGT1R (A1166C) gene polymorphisms and investigating the association of these polymorphism with the development of DN in Iraqi patients with Type 2 diabetes mellitus (T2DM) and evaluating the levels of several urinary and serum markers in relation to studied polymorphisms. This is a cross-sectional study that included 161 T2DM patients whom were divided into two groups: T2DM with DN(included 98 patients) and normalbuminuric T2DM (included 63 patients). ACE gene polymorphism analysis revealed that the D allele was far more prevalent in DN patients compared to normalbuminuric patients (60.2% vs. 50.8%), while the I allele frequency was 39.8% in DN and 49.2% in normoalbuminuric patients. In addition, DN patients carrying the DD genotype had higher serum kidney injury molecule 1 (KIM1), serum cystatin C (CysC), and HbA1C and lower glomerular filtration rate (GFR) compared to ID+II genotypes. For AGT1R (A1166C), both DN and normalbuminuric patients had a comparable high prevalence of the AA genotype, followed by the AC genotype, while the CC genotype had been seen only in 3 patients. In conclusion, among the studied T2DM patients, individuals with DD genotype had higher frequency of DN and had 2-fold risk for DN compared to II genotype which had the lowest risk for DN. Also the current study shows that the A1166C polymorphisms of AGT1R distribution frequency were similar for both study groups with higher frequency for A allele compared to C allele and not associated with risk of DN in Iraqi T2DM Keywords: Angiotensin Converting Enzyme (I\D) gene polymorphism, Angiotensin II Type 1 Receptor (A166C) gene polymorphisms, Cystatin C, Diabetic nephropathy, Kidney injury molecule1.

The Role of ACE2 in Neurological Disorders: From Underlying Mechanisms to the Neurological Impact of COVID-19.

Angiotensin-converting enzyme 2 (ACE2) has become a hot topic in neuroscience research in recent years, especially in the context of the global COVID-19 pandemic, where its role in neurological diseases has received widespread attention. ACE2, as a multifunctional metalloprotease, not only plays a critical role in the cardiovascular system but also plays an important role in the protection, development, and inflammation regulation of the nervous system. The COVID-19 pandemic further highlights the importance of ACE2 in the nervous system. SARS-CoV-2 enters host cells by binding to ACE2, which may directly or indirectly affect the nervous system, leading to a range of neurological symptoms. This review aims to explore the function of ACE2 in the nervous system as well as its potential impact and therapeutic potential in various neurological diseases, providing a new perspective for the treatment of neurological disorders.

A GWAS of ACE Inhibitor-Induced Angioedema in a South African Population.

Angiotensin-converting enzyme inhibitor-induced angioedema (AE-ACEI) is a life-threatening adverse event and, globally, the commonest cause of emergency presentations with angioedema. Several large genome-wide association studies (GWAS) have found genomic associations with AE-ACEI. However, despite African Americans having a 5-fold increased risk of AE-ACEI, there are no published GWAS from Africa. The aim of this study was to conduct a case-control GWAS of AE-ACEI in a South African population and perform a meta-analysis with an African American and European American population. The GWAS included 202 South African adults with a history of AE-ACEI and 513 controls without angioedema following angiotensin-converting enzyme inhibitor (ACEI) treatment for at least 2 years. A meta-analysis was conducted with GWAS summary statistics from an African American and European American cohort (from Vanderbilt/Marshfield with 174 cases and 489 controls). No SNPs attained genome-wide significance. However, 26 SNPs in the post-imputation standard GWAS of the South African cohort and 37 SNPs in the meta-analysis were associated to AE-ACEI with suggestive threshold(p-value<5.0×10-06). Some of these SNPs were found to be located close to the genes PRKCQ and RIMS1, previously linked with drug-induced angioedema, and also close to the CSMD1 gene linked to ACEI cough, providing replication at the gene level, but with novel lead SNPs. Our results highlight the importance of African populations to detect novel variants in replication studies. Further increased sampling across the continent and matched functional work are needed to confirm the importance of genetic variation in understanding the biology of AE-ACEI.

Clinical and economic analysis of the use of dapagliflozin in patients with chronic heart failure with reduced left ventricular ejection fraction in various subgroups of standard therapy in the Russian Federation

To evaluate the clinical and economic effectiveness of dapagliflozin in patients with chronic heart failure (CHF) with reduced left ventricular ejection fraction (HFrEF) in the Russian Federation in various subgroups of standard therapy for CHF. A clinical and economic analysis of the use of the drug dapagliflozin in addition to standard therapy was carried out in comparison with standard therapy in various subgroups of standard therapy for HFrEF using a modeling method. Cost calculations were carried out in a mathematical model adapted to the healthcare conditions of the Russian Federation by using Russian cost indicators and characteristics of the patient population. The present study demonstrates that the addition of dapagliflozin is beneficial in terms of clinical and cost-effectiveness, regardless of the initial regimen (angiotensin receptor-neprilysin inhibitors [ARNI] or angiotensin-converting enzyme inhibitors [ACEi]/angiotensin II receptor blockers [ARB]) of standard drug therapy for HFrEF and in all cases leads to an increase in life expectancy, a decrease in the number of hospitalizations and emergency visits due to CHF, as well as cardiovascular mortality. The obtained values of added value per additional year of life in all cases are significantly lower than the willingness-to-pay threshold, which indicates the clinical and economic effectiveness of the strategy of prescribing dapagliflozin as part of standard therapy for patients with HFrEF. In the case of adding dapagliflozin the values of the additional cost of an added year of life in the 3 considered standard therapy options (ARNI or ACEi/ARB, only ACEi/ARB and only ARNI) were 291,256, 279,571 and 338,374 rubles respectively. Thus, the scenario of using dapagliflozin with standard therapy, which included only ACEi/ARB, is characterized by the lowest additional cost and has the best clinical and economic characteristics. At the same time the scenario of use with standard therapy, which included only ARNI, is characterized by the highest value of the additional value of the added year of life.

Angiotensin-Converting Enzyme-2 (ACE2) Downregulation During Coronavirus Infection.

Angiotensin-converting enzyme-2 (ACE2) downregulation represents a detrimental factor in people with a baseline ACE2 deficiency associated with older age, hypertension, diabetes, and cardiovascular diseases. Human coronaviruses, including HCoV-NL63, SARS-CoV-1, and SARS CoV-2 infect target cells via binding of viral spike (S) glycoprotein to the ACE2, resulting in ACE2 downregulation through yet unidentified mechanisms. This downregulation disrupts the enzymatic activity of ACE2, essential in protecting against organ injury by cleaving and disposing of Angiotensin-II (Ang II), leading to the formation of Ang 1-7, thereby exacerbating the accumulation of Ang II. This accumulation activates the Angiotensin II type 1 receptor (AT1R) receptor, leading to leukocyte recruitment and increased proinflammatory cytokines, contributing to organ injury. The biological impacts and underlying mechanisms of ACE2 downregulation during SARS-CoV-2 infection have not been well defined. Therefore, there is an urgent need to establish a solid theoretical and experimental understanding of the mechanisms of ACE2 downregulation during SARS-CoV-2 entry and replication in the host cells. This review aims to discuss the physiological impact of ACE2 downregulation during coronavirus infection, the relationship between ACE2 decline and virus pathogenicity, and the possible mechanisms of ACE2 degradation, along with the therapeutic approaches.

323 Advances in using membrane vesicles for studying intestinal functions

Abstract Enterocytes are the major cell lineage of the small intestinal epithelia along the crypt-villus axis in gut mucosa. Enterocytes participate in the gut terminal nutrient digestion and absorption; and have essential roles in nutrient and metabolite recycling and efflux, nutrient and hormonal sensing, interactions with symbiotic microbiome and binding to infectious viruses, thus influencing the host homeostasis and whole-body physiological status. Intestinal membrane vesicles have been widely used for studying various gut functions in the past several decades. Villus enterocytic brush border membrane and the apical membrane vesicles along the crypt-villus axis in gut mucosa can be prepared and isolated by Mg2+- and Ca2+-precipitation and differential centrifugation procedures. Whereas, gut mucosal basolateral membrane vesicles can be prepared, fractionated and differentiated from other intracellular organelles such as the mitochondrial inner membrane by the Percoll gradient ultracentrifugation. Nutrient transport and exchange activities in the membrane vesicles in vitro are conducted often by rapid hand filtration, and in excess, in an automated fast sampling apparatus. Nutrient transport and exchange activity kinetics are derived according to the well-established classic Michaelis-Menten and the tracer inhibitory kinetic models with a simple linear diffusional component. Physiological and biochemical properties associated with various nutrient uptake systems such as pH optimum, requirements for co-transported ions (e.g., Na+, K+, Cl-), transporter affinity and substrate specificity can be effectively investigated in vitro with the membrane vesicles by altering the compositions of uptake buffers and intra-vesicular pre-loading buffers. Some of the fundamental gut functions are established via using the membrane vesicles in different mammalian species. And these include H+-peptide cotransport, Na+-cotransport and Na+-independent systems of hexose uptake across the apical membrane and the low-affinity Na+-independent hexose bidirectional uptake across the basolateral membrane that were characterized in rodents; Na+-dependent cotransport and Na+-independent systems of amino acid (AA) transport across the apical membrane that were revealed in rodents and pigs; as well as the Na+-hexose and AA cotransport and the co-expression of the coronavirus SARS-CoV-2 host epithelial apical membrane binding receptor, i.e., the angiotensin-converting enzyme-2 (ACE2), along the gut crypt-villus axis that were identified in liquid formula-fed piglets. In the post genomic and metagenomic sequencing era, further research efforts need to pursue understanding of expression and various functionality of the gut terminal hydrolases, nutrient transporters, nutrient exchangers, nutrient sensors, substrate and particle receptors, taste receptors, viral binding receptors such as ACE2 and hormonal receptors and their interactions with luminal factors such as nutrient, metabolites, symbiotic bacterial outer membrane vesicles etc., along the longitudinal and crypt-villus axes, through using the mammalian primary enterocytic apical and the basolateral membrane vesicles under various research settings.

Optimization, physicochemical stability and in vivo study of alginate-chitosan composites as nanocarriers for low molecular weight angiotensin I-converting enzyme (ACE)-inhibitory peptide

Optimization, physicochemical stability and in vivo study of alginate-chitosan composites as nanocarriers for low molecular weight angiotensin I-converting enzyme (ACE)-inhibitory peptide

Anti-hypertensive medications and erectile dysfunction: focus on β-blockers.

Although anti-hypertensive medications, including thiazides and β-blockers (BBs) in particular, have been suggested to cause erectile dysfunction (ED) their real contribution is still conflicting. The aim of this paper is to summarize available evidence providing an evidence-based critical analysis of the topic. An overall comprehensive narrative review was performed using Medline, Embase and Cochrane search. In addition, to better understand the impact of BBs on ED a specific systematic review was also performed. The negative role of centrally acting drugs, such as clonidine and α-methyldopa, is well documented althuogh limited controlled trials are available. Angiotensin-converting enzyme inhibitors (ACEis), angiotensin receptor blockers (ARBs), and calcium-channel-blockers (CCBs) have neutral (CCBs) or even positive (ACEis and ARBs) effects on erectile function. Despite some preliminary negative reports, more recent evidence does not confirm the negative impact of thiazides. BBs should be still considered the class of medications more often associated with ED, although better outcomes can be drawn with nebivolol. Sexual function should be assessed in all patients with arterial hypertension, either at diagnosis or after the prescription of specific medications. A close related patient-physician interaction and discussion can overcome possible negative outcomes allowing a successful management of possible side effects.

Evaluation of Angiotensin-Converting Enzyme 2 Expression In Vivo with Novel 68Ga-Labeled Peptides Originated from the Coronavirus Receptor-Binding Domain.

Angiotensin-converting enzyme 2 (ACE2) is not only a key to the renin-angiotensin-aldosterone system and related diseases, but also the main entry point on cell surfaces for certain coronaviruses, including severe acute respiratory syndrome coronavirus (SARS-CoV) and SARS-CoV-2. By analyzing the different key binding sites from the receptor-binding domain (RBD) of SARS-CoV and SARS-CoV-2, nine new ACE2-targeting peptides (A1 to A9) were designed, synthesized and connected with a chelator, 1,4,7-triazacyclononane-N,N',N''-triacetic acid (NOTA). NOTA-A1, NOTA-A2, NOTA-A4, NOTA-A5, and NOTA-A8 were successfully labeled with [68Ga]Ga3+ and were used for biological evaluation. [68Ga]Ga-NOTA-A2, [68Ga]Ga-NOTA-A5, and [68Ga]Ga-NOTA-A8 showed specific binding to ACE2 via cell assays, and their binding sites and binding capacity were calculated by molecular docking and molecular dynamics simulations. In tumor-bearing mice, A549 tumors were visualized 60 min postinjection of [68Ga]Ga-NOTA-A2, [68Ga]Ga-NOTA-A5, or [68Ga]Ga-NOTA-A8. These peptides also accumulated in the organs with high-level ACE2 expression, confirmed by immunohistochemical stain. Among them, [68Ga]Ga-NOTA-A5 exhibited the highest tumor uptake and tumor/background ratio, and it successfully tracked the increased ACE2 levels in mice tissues after excessive Losartan treatment. In a first-in-human study, the distribution of [68Ga]Ga-NOTA-A5 was evaluated with positron emission tomography/computed tomography (PET/CT) in three participants without adverse events. 68Ga-labeled peptides originated from the coronavirus RBD, with [68Ga]Ga-NOTA-A5 as a typical representative, seem to be safe and effective for the evaluation of ACE2 expression in vivo with PET/CT, facilitating further mechanism investigation and clinical evaluation of ACE2-related diseases.

Implications of Dysnatremia and Endocrine Disturbances in COVID-19 Patients.

Sodium imbalance is a common electrolyte disturbance in COVID-19, often linked to disruptions in hormonal regulation. This review explores the relationship between sodium dysregulation and endocrine disturbances, particularly focusing on primary and secondary hypothyroidism, hypocortisolism, and the renin-angiotensin-aldosterone system (RAAS). Hypocortisolism in COVID-19, due to adrenal insufficiency or secondary to pituitary dysfunction, can lead to hyponatremia through inadequate cortisol levels, which impair renal free water excretion and enhance antidiuretic hormone (ADH) secretion. Similarly, hypothyroidism is associated with decreased renal blood flow and the glomerular filtration rate (GFR), which also increases ADH activity, leading to water retention and dilutional hyponatremia. Furthermore, COVID-19 can disrupt RAAS (primarily through its interaction with the angiotensin-converting enzyme 2 (ACE2) receptor), diminishing aldosterone secretion and further contributing to sodium loss and hyponatremia. These hormonal disruptions suggest that sodium imbalance in COVID-19 is multifactorial and warrants further investigation into the complex interplay between COVID-19, endocrine function, and sodium homeostasis. Future research should focus on understanding these mechanisms to develop management algorithms that address both sodium imbalance and underlying hormonal disturbances in order to improve prognosis and outcomes in COVID-19 patients.