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1.
Biophys J ; 120(14): 2785-2792, 2021 07 20.
Article in English | MEDLINE | ID: covidwho-1603521

ABSTRACT

The entry of the severe acute respiratory syndrome coronavirus 2 virus in human cells is mediated by the binding of its surface spike protein to the human angiotensin-converting enzyme 2 (ACE2) receptor. A 23-residue long helical segment (SBP1) at the binding interface of human ACE2 interacts with viral spike protein and therefore has generated considerable interest as a recognition element for virus detection. Unfortunately, emerging reports indicate that the affinity of SBP1 to the receptor-binding domain of the spike protein is much lower than that of the ACE2 receptor itself. Here, we examine the biophysical properties of SBP1 to reveal factors leading to its low affinity for the spike protein. Whereas SBP1 shows good solubility (solubility > 0.8 mM), circular dichroism spectroscopy shows that it is mostly disordered with some antiparallel ß-sheet content and no helicity. The helicity is substantial (>20%) only upon adding high concentrations (≥20% v/v) of 2,2,2-trifluoroethanol, a helix promoter. Fluorescence correlation spectroscopy and single-molecule photobleaching studies show that the peptide oligomerizes at concentrations >50 nM. We hypothesized that mutating the hydrophobic residues (F28, F32, and F40) of SBP1, which do not directly interact with the spike protein, to alanine would reduce peptide oligomerization without affecting its spike binding affinity. Whereas the mutant peptide (SBP1mod) shows substantially reduced oligomerization propensity, it does not show improved helicity. Our study shows that the failure of efforts, so far, to produce a short SBP1 mimic with a high affinity for the spike protein is not only due to the lack of helicity but is also due to the heretofore unrecognized problem of oligomerization.


Subject(s)
COVID-19 , Peptidyl-Dipeptidase A , Angiotensin-Converting Enzyme 2 , Humans , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Protein Binding , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism
2.
Mayo Clin Proc ; 95(7): 1354-1368, 2020 07.
Article in English | MEDLINE | ID: covidwho-1500136

ABSTRACT

OBJECTIVE: To explore the transcriptomic differences between patients with hypertrophic cardiomyopathy (HCM) and controls. PATIENTS AND METHODS: RNA was extracted from cardiac tissue flash frozen at therapeutic surgical septal myectomy for 106 patients with HCM and 39 healthy donor hearts. Expression profiling of 37,846 genes was performed using the Illumina Human HT-12v3 Expression BeadChip. All patients with HCM were genotyped for pathogenic variants causing HCM. Technical validation was performed using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. This study was started on January 1, 1999, and final analysis was completed on April 20, 2020. RESULTS: Overall, 22% of the transcriptome (8443 of 37,846 genes) was expressed differentially between HCM and control tissues. Analysis by genotype revealed that gene expression changes were similar among genotypic subgroups of HCM, with only 4% (1502 of 37,846) to 6% (2336 of 37,846) of the transcriptome exhibiting differential expression between genotypic subgroups. The qRT-PCR confirmed differential expression in 92% (11 of 12 genes) of tested transcripts. Notably, in the context of coronavirus disease 2019 (COVID-19), the transcript for angiotensin I converting enzyme 2 (ACE2), a negative regulator of the angiotensin system, was the single most up-regulated gene in HCM (fold-change, 3.53; q-value =1.30×10-23), which was confirmed by qRT-PCR in triplicate (fold change, 3.78; P=5.22×10-4), and Western blot confirmed greater than 5-fold overexpression of ACE2 protein (fold change, 5.34; P=1.66×10-6). CONCLUSION: More than 20% of the transcriptome is expressed differentially between HCM and control tissues. Importantly, ACE2 was the most up-regulated gene in HCM, indicating perhaps the heart's compensatory effort to mount an antihypertrophic, antifibrotic response. However, given that the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) uses ACE2 for viral entry, this 5-fold increase in ACE2 protein may confer increased risk for COVID-19 manifestations and outcomes in patients with increased ACE2 transcript expression and protein levels in the heart.


Subject(s)
Betacoronavirus , Cardiomyopathy, Hypertrophic/genetics , Cardiomyopathy, Hypertrophic/virology , Coronavirus Infections/complications , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Pneumonia, Viral/complications , Adolescent , Adult , Aged , Angiotensin-Converting Enzyme 2 , COVID-19 , Cardiomyopathy, Hypertrophic/metabolism , Case-Control Studies , Child , Genotype , Humans , Middle Aged , Myocardium/metabolism , Pandemics , RNA, Messenger/metabolism , Real-Time Polymerase Chain Reaction , SARS-CoV-2 , Young Adult
3.
Am J Respir Crit Care Med ; 204(9): 1024-1034, 2021 11 01.
Article in English | MEDLINE | ID: covidwho-1495777

ABSTRACT

Rationale: ACE2 (angiotensin-converting enzyme 2), the entry receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is expressed in type 2 alveolar epithelial cells (AT2) that may play key roles in postinjury repair. An imbalance between ACE2 and ACE has also been hypothesized to contribute to lung injury. Objectives: To characterize the expression and distribution of ACE2 and ACE and to compare AT2 with endothelial cell expression in coronavirus disease (COVID-19)-related or -unrelated acute respiratory distress syndrome (ARDS) and controls. Methods: Lung tissue stainings (using multiplex immunofluorescence) and serum concentrations of ACEs were determined retrospectively in two different cohorts of patients. AT2 and endothelial cells were stained in lung tissue for ProSPC (pro-surfactant protein C) and CD31, respectively. Measurements and Main Results: Pulmonary ACE2 expression was increased in patients with COVID-19-related and -unrelated ARDS (0.06% of tissue area and 0.12% vs. 0.006% for control subjects; P = 0.013 and P < 0.0001, respectively). ACE2 was upregulated in endothelial cells (0.32% and 0.53% vs. 0.01%; P = 0.009 and P < 0.0001) but not in AT2 cells (0.13% and 0.08% vs. 0.03%; P = 0.94 and P = 0.44). Pulmonary expression of ACE was decreased in both COVID-19-related and -unrelated ARDS (P = 0.057 and P = 0.032). Similar increases in ACE2 and decreases in ACE were observed in sera of COVID-19 (P = 0.0054 and P < 0.0001) and non-COVID-19 ARDS (P < 0.0001 and P = 0.016). In addition, AT2 cells were decreased in patients with COVID-19-related ARDS compared with COVID-19-unrelated ARDS (1.395% vs. 2.94%, P = 0.0033). Conclusions: ACE2 is upregulated in lung tissue and serum of both COVID-19-related and -unrelated ARDS, whereas a loss of AT2 cells is selectively observed in COVID-19-related ARDS.


Subject(s)
Alveolar Epithelial Cells/metabolism , Angiotensin-Converting Enzyme 2/metabolism , COVID-19/metabolism , Peptidyl-Dipeptidase A/metabolism , Respiratory Distress Syndrome/metabolism , Adult , Aged , Biomarkers/metabolism , COVID-19/diagnosis , COVID-19/physiopathology , Case-Control Studies , Female , Humans , Immunohistochemistry , Logistic Models , Male , Middle Aged , Proportional Hazards Models , Respiratory Distress Syndrome/diagnosis , Respiratory Distress Syndrome/virology , Retrospective Studies , Severity of Illness Index , Up-Regulation
5.
Cells ; 10(10)2021 10 14.
Article in English | MEDLINE | ID: covidwho-1470799

ABSTRACT

The renin-angiotensin system (RAS) plays a pivotal role in a wide series of physiological processes, among which inflammation and blood pressure regulation. One of its key components, the angiotensin-converting enzyme 2, has been identified as the entry point of the SARS-CoV-2 virus into the host cells, and therefore a lot of research has been devoted to study RAS dysregulation in COVID-19. Here we discuss the alterations of the regulatory RAS axes due to SARS-CoV-2 infection on the basis of a series of recent clinical investigations and experimental analyzes quantifying, e.g., the levels and activity of RAS components. We performed a comprehensive meta-analysis of these data in view of disentangling the links between the impaired RAS functioning and the pathophysiological characteristics of COVID-19. We also review the effects of several RAS-targeting drugs and how they could potentially help restore the normal RAS functionality and minimize the COVID-19 severity. Finally, we discuss the conflicting evidence found in the literature and the open questions on RAS dysregulation in SARS-CoV-2 infection whose resolution would improve our understanding of COVID-19.


Subject(s)
COVID-19/blood , COVID-19/metabolism , Renin-Angiotensin System , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Animals , Blood Pressure/drug effects , Humans , Peptidyl-Dipeptidase A/metabolism , Renin/pharmacology , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/chemistry
6.
J Clin Invest ; 131(19)2021 10 01.
Article in English | MEDLINE | ID: covidwho-1448084

ABSTRACT

BACKGROUNDThe angiotensin-converting enzyme (ACE) D allele is more prevalent among African Americans compared with other races and ethnicities and has previously been associated with severe coronavirus disease 2019 (COVID-19) pathogenesis through excessive ACE1 activity. ACE inhibitors/angiotensin receptor blockers (ACE-I/ARB) may counteract this mechanism, but their association with COVID-19 outcomes has not been specifically tested in the African American population.METHODSWe identified 6218 patients who were admitted into Mount Sinai hospitals with COVID-19 between February 24 and May 31, 2020, in New York City. We evaluated whether the outpatient and in-hospital use of ACE-I/ARB is associated with COVID-19 in-hospital mortality in an African American compared with non-African American population.RESULTSOf the 6218 patients with COVID-19, 1138 (18.3%) were ACE-I/ARB users. In a multivariate logistic regression model, ACE-I/ARB use was independently associated with a reduced risk of in-hospital mortality in the entire population (OR, 0.655; 95% CI, 0.505-0.850; P = 0.001), African American population (OR, 0.44; 95% CI, 0.249-0.779; P = 0.005), and non-African American population (OR, 0.748, 95% CI, 0.553-1.012, P = 0.06). In the African American population, in-hospital use of ACE-I/ARB was associated with improved mortality (OR, 0.378; 95% CI, 0.188-0.766; P = 0.006), whereas outpatient use was not (OR, 0.889; 95% CI, 0.375-2.158; P = 0.812). When analyzing each medication class separately, ARB in-hospital use was significantly associated with reduced in-hospital mortality in the African American population (OR, 0.196; 95% CI, 0.074-0.516; P = 0.001), whereas ACE-I use was not associated with impact on mortality in any population.CONCLUSIONIn-hospital use of ARB was associated with a significant reduction in in-hospital mortality among COVID-19-positive African American patients.FUNDINGNone.


Subject(s)
African Americans , Angiotensin Receptor Antagonists/administration & dosage , Angiotensin-Converting Enzyme Inhibitors/administration & dosage , COVID-19 , Hospital Mortality/ethnology , SARS-CoV-2/metabolism , Aged , COVID-19/drug therapy , COVID-19/ethnology , COVID-19/metabolism , COVID-19/mortality , Disease-Free Survival , Female , Humans , Male , Middle Aged , Peptidyl-Dipeptidase A/metabolism , Retrospective Studies , Survival Rate
7.
J Infect Public Health ; 14(11): 1686-1692, 2021 Nov.
Article in English | MEDLINE | ID: covidwho-1446871

ABSTRACT

As far as comorbidity is concerned, cardiovascular diseases (CVD) appear to be accounted for the highest prevalence, severity, and fatality among COVID 19 patients. A wide array of causal links connecting CVD and COVID-19 baffle the overall prognosis as well as the efficacy of the given therapeutic interventions. At the centre of this puzzle lies ACE2 that works as a receptor for the SARS-CoV-2, and functional expression of which is also needed to minimize vasoconstriction otherwise would lead to high blood pressure. Furthermore, SARS-CoV-2 infection seems to reduce the functional expression of ACE2. Given these circumstances, it might be advisable to consider a treatment plan for COVID-19 patients with CVD in an approach that would neither aggravate the vasodeleterious arm of the renin-angiotensinogen-aldosterone system (RAAS) nor compromise the vasoprotective arm of RAAS but is effective to minimize or if possible, inhibit the viral replication. Given the immune modulatory role of Zn in both CVD and COVID-19 pathogenesis, zinc supplement to the selective treatment plan for CVD and COVID-19 comorbid conditions, to be decided by the clinicians depending on the cardiovascular conditions of the patients, might greatly improve the therapeutic outcome. Notably, ACE2 is a zinc metalloenzyme and zinc is also known to inhibit viral replication.


Subject(s)
COVID-19 , Cardiovascular Diseases , Angiotensin-Converting Enzyme 2 , Cardiovascular Diseases/epidemiology , Comorbidity , Humans , Peptidyl-Dipeptidase A/metabolism , Renin-Angiotensin System , SARS-CoV-2 , Zinc
8.
Genes (Basel) ; 12(10)2021 10 01.
Article in English | MEDLINE | ID: covidwho-1444159

ABSTRACT

The renin-angiotensin-aldosterone system (RAAS) appears to play an important role in SARS-CoV-2 infection. Polymorphisms within the genes that control this enzymatic system are candidates for elucidating the pathogenesis of COVID-19, since COVID-19 is not only a pulmonary disease but also affects many organs and systems throughout the body in multiple ways. Most striking is the fact that ACE2, one of the major components of the RAAS, is a prerequisite for SARS-COV-2 infection. Recently, we and other groups reported an association between a polymorphism of the ACE1 gene (a homolog of ACE2) and the phenotypic expression of COVID-19, particularly in its severity. The ethnic difference in ACE1 insertion (I)/deletion (D) polymorphism seems to explain the apparent difference in mortality between the West and East Asia. The purpose of this review was to further evaluate the evidence linking ACE1 polymorphisms to COVID-19. We searched the Medline database (2019-2021) for reference citations of relevant articles and selected studies on the clinical outcome of COVID-19 related to ACE1 I/D polymorphism. Although the numbers of patients are not large enough yet, most available evidence supports the notion that the DD genotype adversely influences COVID-19 symptoms. Surprisingly, small studies conducted in several countries yielded opposite results, suggesting that the ACE1 II genotype is a risk factor. This contradictory result may be the case in certain geographic areas, especially in subgroups of patients. It may also be due to interactions with other genes or to yet unexplained biochemical mechanisms. According to our hypothesis, such candidates are genes that are functionally involved in the pathophysiology of COVID-19, can act in concert with the ACE1 DD genotype, and that show differences in their frequency between the West and East Asia. For this, we conducted research focusing on Alu-related genes. The current study on the ACE1 genotype will provide potentially new clues to the pathogenesis, treatment, and diagnosis of SARS-CoV-2 infections.


Subject(s)
COVID-19 , Gene Expression Regulation, Viral , Genotype , INDEL Mutation , Peptidyl-Dipeptidase A , Polymorphism, Genetic , SARS-CoV-2/metabolism , COVID-19/genetics , COVID-19/metabolism , Humans , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Risk Factors
9.
PLoS One ; 16(9): e0257905, 2021.
Article in English | MEDLINE | ID: covidwho-1440993

ABSTRACT

SARS-CoV-2 virus, the causative agent of Covid-19, has fired up a global pandemic. The virus interacts with the human receptor angiotensin-converting enzyme 2 (ACE2) for an invasion via receptor binding domain (RBD) on its spike protein. To provide a deeper understanding of this interaction, we performed microsecond simulations of the RBD-ACE2 complex for SARS-CoV-2 and compared it with the closely related SARS-CoV discovered in 2003. We show residues in the RBD of SARS-CoV-2 that were mutated from SARS-CoV, collectively help make the RBD anchor much stronger to the N-terminal part of ACE2 than the corresponding residues on RBD of SARS-CoV. This would result in a reduced dissociation rate of SARS-CoV-2 from human receptor protein compared to SARS-CoV. The phenomenon was consistently observed in simulations beyond 500 ns and was reproducible across different force fields. Altogether, our study adds more insight into the critical dynamics of the key residues at the virus spike and human receptor binding interface and potentially aids the development of diagnostics and therapeutics to combat the pandemic efficiently.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , COVID-19/metabolism , SARS-CoV-2/genetics , Angiotensin-Converting Enzyme 2/genetics , Binding Sites , COVID-19/genetics , Humans , Models, Theoretical , Molecular Dynamics Simulation , Pandemics , Peptidyl-Dipeptidase A/metabolism , Protein Binding , Protein Domains , Protein Interaction Domains and Motifs/genetics , Protein Interaction Domains and Motifs/physiology , SARS-CoV-2/pathogenicity , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism
11.
Cells ; 10(9)2021 09 15.
Article in English | MEDLINE | ID: covidwho-1408625

ABSTRACT

Coronavirus disease 19 (COVID-19) is caused by an enveloped, positive-sense, single-stranded RNA virus, referred to as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which belongs to the realm Riboviria, order Nidovirales, family Coronaviridae, genus Betacoronavirus and the species Severe acute respiratory syndrome-related coronavirus. This viral disease is characterized by a myriad of varying symptoms, such as pyrexia, cough, hemoptysis, dyspnoea, diarrhea, muscle soreness, dysosmia, lymphopenia and dysgeusia amongst others. The virus mainly infects humans, various other mammals, avian species and some other companion livestock. SARS-CoV-2 cellular entry is primarily accomplished by molecular interaction between the virus's spike (S) protein and the host cell surface receptor, angiotensin-converting enzyme 2 (ACE2), although other host cell-associated receptors/factors, such as neuropilin 1 (NRP-1) and neuropilin 2 (NRP-2), C-type lectin receptors (CLRs), as well as proteases such as TMPRSS2 (transmembrane serine protease 2) and furin, might also play a crucial role in infection, tropism, pathogenesis and clinical outcome. Furthermore, several structural and non-structural proteins of the virus themselves are very critical in determining the clinical outcome following infection. Considering such critical role(s) of the abovementioned host cell receptors, associated proteases/factors and virus structural/non-structural proteins (NSPs), it may be quite prudent to therapeutically target them through a multipronged clinical regimen to combat the disease.


Subject(s)
COVID-19 , Host Microbial Interactions , SARS-CoV-2/pathogenicity , Angiotensin-Converting Enzyme 2/chemistry , Angiotensin-Converting Enzyme 2/metabolism , Animals , COVID-19/pathology , COVID-19/virology , Drug Delivery Systems , Furin/chemistry , Furin/metabolism , Humans , Lectins, C-Type/chemistry , Lectins, C-Type/metabolism , Molecular Structure , Neuropilins/chemistry , Neuropilins/metabolism , Peptidyl-Dipeptidase A/chemistry , Peptidyl-Dipeptidase A/metabolism , Protein Binding , Receptors, Virus/chemistry , Receptors, Virus/metabolism , Serine Endopeptidases/chemistry , Serine Endopeptidases/metabolism , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism , Treatment Outcome , Viral Nonstructural Proteins/chemistry , Viral Nonstructural Proteins/metabolism , Virus Internalization
12.
Biochem Biophys Res Commun ; 577: 146-151, 2021 11 05.
Article in English | MEDLINE | ID: covidwho-1401239

ABSTRACT

The human lung cell A549 is susceptible to infection with a number of respiratory viruses. However, A549 cells are resistant to Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) infection in conventional submerged culture, and this would appear to be due to low expression levels of the SARS-CoV-2 entry receptor: angiotensin-converting enzyme-2 (ACE2). Here, we examined SARS-CoV-2 susceptibility to A549 cells after adaptation to air-liquid interface (ALI) culture. A549 cells in ALI culture yielded a layer of mucus on their apical surface, exhibited decreased expression levels of the proliferation marker KI-67 and intriguingly became susceptible to SARS-CoV-2 infection. We found that A549 cells increased the endogenous expression levels of ACE2 and TMPRSS2 following adaptation to ALI culture conditions. Camostat, a TMPRSS2 inhibitor, reduced SARS-CoV-2 infection in ALI-cultured A549 cells. These findings indicate that ALI culture switches the phenotype of A549 cells from resistance to susceptibility to SARS-CoV-2 infection through upregulation of ACE2 and TMPRSS2.


Subject(s)
Alveolar Epithelial Cells/virology , COVID-19/virology , Cell Culture Techniques/methods , SARS-CoV-2/physiology , A549 Cells , Alveolar Epithelial Cells/pathology , Cells, Cultured , Disease Susceptibility , Gene Expression Regulation, Neoplastic , Humans , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Serine Endopeptidases/genetics , Serine Endopeptidases/metabolism , Up-Regulation/genetics
16.
Signal Transduct Target Ther ; 5(1): 220, 2020 10 06.
Article in English | MEDLINE | ID: covidwho-1387194
19.
J Assist Reprod Genet ; 37(11): 2657-2660, 2020 Nov.
Article in English | MEDLINE | ID: covidwho-1384515

ABSTRACT

PURPOSE: To visualize SARS-CoV-2 host receptors ACE2 and CD147 on human oocytes and blastocysts. METHODS: Immunohistochemistry and confocal microscopy on human primary oocytes and pre (5 days post fertilization (dpf5) and (dpf6))- and peri (dpf7)-implantation blastocysts donated to research. RESULTS: SARS-CoV-2 host receptors ACE2 and CD147 are present on the membrane of trophectoderm, epiblast and hypoblast cells in human blastocysts. CD147 is also present on the oolemma. CONCLUSION: Theoretically, the earliest stages of embryonic development may be vulnerable for SARS-CoV-2 infection.


Subject(s)
Basigin/metabolism , Blastocyst/metabolism , Oocytes/metabolism , Peptidyl-Dipeptidase A/metabolism , Angiotensin-Converting Enzyme 2 , Female , Humans , Immunohistochemistry
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