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1.
J Infect Dis ; 2022 May 11.
Article in English | MEDLINE | ID: covidwho-1840054

ABSTRACT

BACKGROUND: Third COVID-19 vaccine doses are broadly recommended, but immunogenicity data remain limited, particularly in older adults. METHODS: We measured circulating antibodies against the SARS-CoV-2 spike protein receptor-binding domain, ACE2 displacement, and virus neutralization against ancestral and Omicron (BA.1) strains from pre-vaccine up to one month following the third dose, in 151 adults aged 24-98 years who received COVID-19 mRNA vaccines. RESULTS: Following two vaccine doses, humoral immunity was weaker, less functional and less durable in older adults, where a higher number of chronic health conditions was a key correlate of weaker responses and poorer durability. One month after the third dose, antibody concentrations and function exceeded post-second-dose levels, and responses in older adults were comparable in magnitude to those in younger adults at this time. Humoral responses against Omicron were universally weaker than against the ancestral strain after both the second and third doses. Nevertheless, after three doses, anti-Omicron responses in older adults reached equivalence to those in younger adults. One month after three vaccine doses, the number of chronic health conditions, but not age, was the strongest consistent correlate of weaker humoral responses. CONCLUSION: Results underscore the immune benefits of third COVID-19 vaccine doses, particularly in older adults.

2.
Pakistan Journal of Zoology ; 54(1):433, 2022.
Article in English | ProQuest Central | ID: covidwho-1837597

ABSTRACT

Coronavirus disease 2019 (COVID-19) is a pandemic and this disease has infected millions of people globally now. COVID-19 is caused by a novel beta coronavirus strain known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Once SARS-CoV-2 manages to enter the body, it identifies and binds to the angiotensin converting enzyme 2 (ACE2) receptors through the binding receptor of Spike Protein (S-protein). The present study aimed to investigate the phytochemicals as potential inhibitors of the binding domain of S protein so that the binding of COVID-19 with ACE2 receptors could be restrained. For this purpose, the library of 2113 phytochemicals was docked against the binding domain of the S-protein. Top ten compounds with maximum binding affinity to the active sites of target protein were further screened for ADMET properties by adopting SwissADME and ADMETsar online servers. The compounds namely Morin, Curcumin, Apigenin, Cedronolactone A and Matairesinol showed acceptable drug-like properties therefore these compounds can be proposed as effective inhibitors, disrupting the S-protein-ACE2 interaction. This study might help in the development of a natural and cost-effective drug against COVID-19. Further, in vivo and in vitro examinations are required to validate our results.

3.
Nature Communications ; 13(1), 2022.
Article in English | ProQuest Central | ID: covidwho-1837520

ABSTRACT

Engineered natural killer (NK) cells represent a promising option for immune therapy option due to their immediate availability in allogeneic settings. Severe acute diseases, such as COVID-19, require targeted and immediate intervention. Here we show engineering of NK cells to express (1) soluble interleukin-15 (sIL15) for enhancing their survival and (2) a chimeric antigen receptor (CAR) consisting of an extracellular domain of ACE2, targeting the spike protein of SARS-CoV-2. These CAR NK cells (mACE2-CAR_sIL15 NK cells) bind to VSV-SARS-CoV-2 chimeric viral particles as well as the recombinant SARS-CoV-2 spike protein subunit S1 leading to enhanced NK cell production of TNF-α and IFN-γ and increased in vitro and in vivo cytotoxicity against cells expressing the spike protein. Administration of mACE2-CAR_sIL15 NK cells maintains body weight, reduces viral load, and prolongs survival of transgenic mice expressing human ACE2 upon infection with live SARS-CoV-2. These experiments, and the capacity of mACE2-CAR_sIL15 NK cells to retain their activity following cryopreservation, demonstrate their potential as an allogeneic off-the-shelf therapy for COVID-19 patients who are faced with limited treatment options.Severe COVID-19 requires immediate and targeted intervention that is efficient against SARS-CoV-2 and its variants. Authors show here the therapeutic potential of engineered natural killer cells that simultaneously express a chimeric antigen receptor targeting the spike protein of SARS-CoV-2, and IL-15, a cytokine that enhances the function and survival of their own.

4.
The New England Journal of Medicine ; 382(24):1653-1659, 2020.
Article in English | ProQuest Central | ID: covidwho-1837006

ABSTRACT

To the Editor: In their Special Report, Vaduganathan and colleagues (April 23 issue)1 describe the use of renin–angiotensin–aldosterone system (RAAS) inhibitors in patients with coronavirus disease 2019 (Covid-19). We would like to add the following points. First, it is worthwhile noting that studies involving in vitro human and animal cell cultures have shown that the effector peptide product of angiotensin-converting enzyme 2 (ACE2), angiotensin-(1–7), is degraded by the dipeptidase ACE into angiotensin-(1–5), and ACE inhibitors increase circulating levels of angiotensin-(1–7) in patients with chronic heart failure.2 This action provides a plausible mechanism for the increase in levels of angiotensin-(1–7) mediated . . .

5.
Int J Infect Dis ; 120: 1-11, 2022 Jul.
Article in English | MEDLINE | ID: covidwho-1838874

ABSTRACT

OBJECTIVES: This study aimed to explore the role of CD4+ T cells in the mechanisms of COVID-19 related diarrhea. METHODS: We analyzed lymphocyte subsets in patients with COVID-19 and the expression of angiotensin-converting enzyme 2 (ACE2), the transmembrane protease serine 2, and CD4+ T cell-related indicators in the colon were compared between patients with and without diarrhea. Correlation analyses were performed for ACE2 and other indicators to identify the relationship between SARS-CoV-2 infection and CD4+ mediated inflammation. The expression and distribution of CD4+ T cell-associated chemokines and their receptors were detected to determine the possibility of migration of CD4+ T cells to inflammation sites. RESULTS: The CD4+ T cell counts and percentages and CD4/CD8 ratio showed the most significant differences between the 2 groups. The diarrhea group expressed higher levels of ACE2, T-box expressed in T cells (Tbet), and tumor necrosis factor-alpha (TNFα) at both the mRNA and protein levels, with no difference from the nondiarrhea group for the percentage of ACE2+TNFα+ cells, indicating an indirect association between ACE2 and TNFα. The mRNA expression of CXCL10, CXCL11, and CXCR3 and the number of CD4+CXCR3+T cells were increased in the diarrhea group. CONCLUSIONS: CD4+ T cell-mediated inflammation may contribute to COVID-19 related diarrhea. CXCR3+ mediated migration of CD4+ T cells into the gut may perpetuate inflammation.

6.
Egyptian Journal of Chemistry ; 65(6):305-310, 2022.
Article in English | Scopus | ID: covidwho-1836280

ABSTRACT

The goal of this study was to examine the changes in salivary biochemical markers such as AST, ALT, GGT, albumin, and C-RP in COVD-19 patients (n=50) to control subjects (n=50). Methods: Whole saliva samples were taken from fifty persons who were matched with sex and age and were then divided into two groups: healthy (n = 50) and COVID-19 (n = 50).Student's t-test and the Correlation-Coefficient test were used to determine statistical significance. The data is presented as a mean standard deviation. A spectrophotometric kit was used to quantify salivary AST, AST, ALP GGT, LDH, and albumin levels, while a conventional enzyme-linked immunosorbent test was used to determine CRP amounts. COVID-19 patients had significantly greater salivary levels of AST, AST, ALP GGT, LDH, and C-RP than controls. However, when compared to the control group, salivary albumin levels in COVID-19 patients were considerably lower. Conclusion: Elevated salivary ALP, AST, AST, GGT, and CRP levels in COVID-19 patients suggest salivary gland injury and could serve as a salivary marker for salivary gland involvement in COVID-19. © 2022 NIDOC (Nat.Inform.Document.Centre). All rights reserved.

7.
Int J Mol Sci ; 23(7)2022 Mar 28.
Article in English | MEDLINE | ID: covidwho-1834807

ABSTRACT

Angiotensin-converting enzyme 2 (ACE2) is a protein widely expressed in numerous cell types, with different biological roles mainly related to the renin-angiotensin system. Recently, ACE2 has been in the spotlight due to its involvement in the SARS-CoV-2 entry into cells. There are no data available regarding the expression of ACE2 and its short-ACE2 isoform at the protein level on human spermatozoa. Here, protein expression was demonstrated by western blot and the percentage of sperm displaying surface ACE2 was assessed by flow cytometry. Immunocytochemistry assays showed that full-length ACE2 was mainly expressed in sperm midpiece, while short ACE2 was preferentially distributed on the equatorial and post-acrosomal region of the sperm head. To our knowledge, this is the first study demonstrating the expression of protein ACE2 on spermatozoa. Further studies are warranted to determine the role of ACE2 isoforms in male reproduction.


Subject(s)
Angiotensin-Converting Enzyme 2 , COVID-19 , Humans , Male , Protein Isoforms/genetics , Protein Isoforms/metabolism , SARS-CoV-2 , Spermatozoa/metabolism
8.
BJOG ; 129(2): 256-266, 2022 01.
Article in English | MEDLINE | ID: covidwho-1831884

ABSTRACT

BACKGROUND: Pregnant women have been identified as a potentially at-risk group concerning COVID-19 infection, but little is known regarding the susceptibility of the fetus to infection. Co-expression of ACE2 and TMPRSS2 has been identified as a prerequisite for infection, and expression across different tissues is known to vary between children and adults. However, the expression of these proteins in the fetus is unknown. METHODS: We performed a retrospective analysis of a single cell data repository. The data were then validated at both gene and protein level by performing RT-qPCR and two-colour immunohistochemistry on a library of second-trimester human fetal tissues. FINDINGS: TMPRSS2 is present at both gene and protein level in the predominantly epithelial fetal tissues analysed. ACE2 is present at significant levels only in the fetal intestine and kidney, and is not expressed in the fetal lung. The placenta also does not co-express the two proteins across the second trimester or at term. INTERPRETATION: This dataset indicates that the lungs are unlikely to be a viable route of SARS-CoV2 fetal infection. The fetal kidney, despite presenting both the proteins required for the infection, is anatomically protected from the exposure to the virus. However, the gastrointestinal tract is likely to be susceptible to infection due to its high co-expression of both proteins, as well as its exposure to potentially infected amniotic fluid. TWEETABLE ABSTRACT: This work provides detailed mechanistic insight into the relative protection & vulnerabilities of the fetus & placenta to SARS-CoV-2 infection by scRNAseq & protein expression analysis for ACE2 & TMPRSS2. The findings help to explain the low rate of vertical transmission.


Subject(s)
Angiotensin-Converting Enzyme 2/genetics , COVID-19 , Gene Expression Profiling , Placenta/metabolism , Serine Endopeptidases/genetics , Adult , COVID-19/epidemiology , COVID-19/genetics , COVID-19/transmission , Databases, Nucleic Acid , Disease Susceptibility/metabolism , Female , Fetal Research , Gene Expression Profiling/methods , Gene Expression Profiling/statistics & numerical data , Genetic Testing/methods , Gestational Age , Humans , Immunohistochemistry , Infectious Disease Transmission, Vertical , Pregnancy , Protective Factors , Ribonucleoproteins, Small Cytoplasmic/analysis , SARS-CoV-2/physiology
9.
Cardiovasc Res ; 2021 Dec 02.
Article in English | MEDLINE | ID: covidwho-1831091

ABSTRACT

AIMS: Since its emergence in early 2020, the novel severe acute respiratory syndrome coronavirus 2 causing coronavirus disease 2019 (COVID-19) has reached pandemic levels, and there have been repeated outbreaks across the globe. The aim of this two-part series is to provide practical knowledge and guidance to aid clinicians in the diagnosis and management of cardiovascular disease (CVD) in association with COVID-19. METHODS AND RESULTS: A narrative literature review of the available evidence has been performed, and the resulting information has been organized into two parts. The first, reported here, focuses on the epidemiology, pathophysiology, and diagnosis of cardiovascular (CV) conditions that may be manifest in patients with COVID-19. The second part, which will follow in a later edition of the journal, addresses the topics of care pathways, treatment, and follow-up of CV conditions in patients with COVID-19. CONCLUSION: This comprehensive review is not a formal guideline but rather a document that provides a summary of current knowledge and guidance to practicing clinicians managing patients with CVD and COVID-19. The recommendations are mainly the result of observations and personal experience from healthcare providers. Therefore, the information provided here may be subject to change with increasing knowledge, evidence from prospective studies, and changes in the pandemic. Likewise, the guidance provided in the document should not interfere with recommendations provided by local and national healthcare authorities.

10.
Front Cell Dev Biol ; 10: 855340, 2022.
Article in English | MEDLINE | ID: covidwho-1834354

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes the Coronavirus disease 2019 (COVID-19), which has resulted in over 5.9 million deaths worldwide. While cells in the respiratory system are the initial target of SARS-CoV-2, there is mounting evidence that COVID-19 is a multi-organ disease. Still, the direct affinity of SARS-CoV-2 for cells in other organs such as the kidneys, which are often targeted in severe COVID-19, remains poorly understood. We employed a human induced pluripotent stem (iPS) cell-derived model to investigate the affinity of SARS-CoV-2 for kidney glomerular podocytes, and examined the expression of host factors for binding and processing of the virus. We studied cellular uptake of the live SARS-CoV-2 virus as well as a pseudotyped virus. Infection of podocytes with live SARS-CoV-2 or spike-pseudotyped lentiviral particles revealed cellular uptake even at low multiplicity of infection (MOI) of 0.01. We found that direct infection of human iPS cell-derived podocytes by SARS-CoV-2 virus can cause cell death and podocyte foot process retraction, a hallmark of podocytopathies and progressive glomerular diseases including collapsing glomerulopathy observed in patients with severe COVID-19 disease. We identified BSG/CD147 and ACE2 receptors as key mediators of spike binding activity in human iPS cell-derived podocytes. These results show that SARS-CoV-2 can infect kidney glomerular podocytes in vitro via multiple binding interactions and partners, which may underlie the high affinity of SARS-CoV-2 for kidney tissues. This stem cell-derived model is potentially useful for kidney-specific antiviral drug screening and mechanistic studies of COVID-19 organotropism.

11.
NMC Case Rep J ; 9: 63-67, 2022.
Article in English | MEDLINE | ID: covidwho-1834117

ABSTRACT

Coronavirus disease 2019 (COVID-19)-related intracranial hemorrhage (ICH) is believed to be associated with at least one known risk factor for ICH, such as hypertension, hyperlipidemia, diabetes mellitus, severe pneumonia, or anticoagulation therapy. However, in this study, we report a case of ICH in a 14-year-old boy with mild COVID-19 infection without pneumonia who had no such risk factors. The only abnormal laboratory finding was temporary depletion of vitamin K-dependent coagulation factors. This case indicates that COVID-19 infection may cause simultaneous asymptomatic intracranial microhemorrhages and temporary depletion of vitamin K-dependent coagulation factors. This temporary depletion might transform the intracranial microhemorrhages into symptomatic ICH.

12.
Transl Med Commun ; 7(1): 2, 2022.
Article in English | MEDLINE | ID: covidwho-1833367

ABSTRACT

BACKGROUND: SARS-CoV-2 developed global-pandemic with millions of infections/deaths. As it is urgently necessary it is assumed that some blockers/inhibitors of ACE2 could be helpful to resist the binding of viral-spike Receptor-Binding-Domain (RBD). METHODS: Here, conserved RBD from 186-countries were compared with WUHAN-Hu-1 wild-type (CLUSTAL-X2/Pymol). The RBD of ACE2-bound nCOV2 crystal-structure 6VW1 was analyzed by Haddock-PatchDock. Extensive structural study/trial to introduce point/double/triple mutations in the different locations of CUT4 (most-effective from total 4 proposed fragments; CUTs) were tested with Swiss-Model-Expacy. RESULTS: Blind-docking of mutated-CUTs in ACE2 completely rejected the nCOV2 binding to ACE2. Further, competitive-docking/binding-analyses (by PRODIGY) demonstrated few more bonding (LYS31-PHE490 and GLN42-GLN498) of CUT4 (than wild) and hindered TYR41-THR500 interaction with ACE2. Moreover, mutated-CUT4 even showed higher blocking effect against spike-ACE2 binding. CONCLUSION: In summary, CUT4-mutant rejects whole glycosylated-nCoV2 in all pre-dock, post-dock and competitive-docking conditions. The present work strategy is relevant because it could be able to block at the first level entry of the virus to the host cells. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s41231-022-00109-5.

13.
Nucleosides Nucleotides Nucleic Acids ; : 1-37, 2022 May 09.
Article in English | MEDLINE | ID: covidwho-1830783

ABSTRACT

Viruses have multiple mutation rates that are higher than any other member of the kingdom of life. This gives them the ability to evolve, even within the course of a single infection, and to evade multiple host defenses, thereby impacting pathogenesis. Additionally, there are also interplays between mutation and recombination and the high multiplicity of infection (MOI) that enhance viral adaptability and increase levels of recombination leading to complex and conflicting effects on genome selection, and the net results is difficult to predict. Recently, the outbreak of COVID-19 virus represents a pandemic threat that has been declared a public health emergency of international concern. Up to present, however, due to the high mutation rate of COVID-19 virus, there are no effective procedures to contain the spread of this virus across the globe. For such a purpose, there is then an urgent need to explore new approaches. As an opinion, the present approach emphasizes on (a) the use of a nonspecific way of blocking the entry of COVID-19 virus as well as its variants into the cells via a therapeutic biocompatible compound (ideally, "in a pill") targeting its spike (S) glycoprotein; and (b) the construction of expression vectors via the glycosyl-phosphatidylinositol, GPI, anchor for studying intermolecular interactions between the spike S of COVID-19 virus as well as its variants and the angiotensin-converting enzyme 2 (ACE2) of its host receptor for checking the efficacy of any therapeutic biocompatible compound of the nonspecific way of blocking. Such antiviral drug would be safer than the ACE1 and ACE2 inhibitors/angiotensin receptor blockers, and recombinant human ACE2 as well as nucleoside analogs or protease inhibitors used for fighting the spread of the virus inside the cells, and it would also be used as a universal one for any eventual future pandemic related to viruses, especially the RNA viruses with high mutation rates.

14.
ACS Nano ; 2022 May 05.
Article in English | MEDLINE | ID: covidwho-1829974

ABSTRACT

The COVID-19 pandemic has been inflicted upon humanity by the SARS-CoV-2 virus, the latest insidious incarnation of the coronaviruses group. While in its wake intense scientific research has produced breakthrough vaccines and cures, there still exists an immediate need to further understand the origin, mechanobiology and biochemistry, and destiny of this virus so that future pandemics arising from similar coronaviruses may be contained more effectively. In this Perspective, we discuss the various evidential findings of virus propagation and connect them to respective underpinning cellular biomechanical states leading to corresponding manifestations of the viral activity. We further propose avenues to tackle the virus, including from a "musical" vantage point, and contain its relentless strides that are currently afflicting the global populace.

15.
Eur J Immunol ; 2022 May 07.
Article in English | MEDLINE | ID: covidwho-1825936

ABSTRACT

Human nasal mucosa is susceptible to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and serves as a reservoir for viral replication before spreading to other organs (e.g. the lung and brain) and transmission to other individuals. Chronic rhinosinusitis (CRS) is a common respiratory tract disease and there is evidence suggesting that susceptibility to SARS-CoV-2 infection differs between the two known subtypes, eosinophilic CRS and non-ECRS (NECRS). However, the mechanism of SARS-CoV-2 infection in the human nasal mucosa and its association with CRS has not been experimentally validated. In this study, we investigated whether the human nasal mucosa is susceptible to SARS-CoV-2 infection and how different endotypes of CRS impact on viral infection and progression. Primary human nasal mucosa tissue culture revealed highly efficient SARS-CoV-2 viral infection and production, with particularly high susceptibility in the NECRS group. The gene expression differences suggested that human nasal mucosa is highly susceptible to SARS-CoV-2 infection, presumably due to an increase in ACE2-expressing cells and a deficiency in antiviral immune response, especially for NECRS. Importantly, patients with NECRS may be at a particularly high risk of viral infection and transmission, and therefore, close monitoring should be considered.

16.
Adv Biol (Weinh) ; : e2101327, 2022 May 06.
Article in English | MEDLINE | ID: covidwho-1825809

ABSTRACT

Sars-Cov-2 may trigger molecular and functional alterations of cardiomyocytes (CMs) of the heart due to the presence of receptor angiotensin-converting enzyme 2 (ACE2) of the host cells. While the endocytic itinerary of the virus via cleavage of the spike protein of Sars-Cov-2 is well understood, the role of the remaining part of the spike protein subunit and ACE2 complex is still elusive. Herein, the possible effects of this complex are investigated by using synthetic spike proteins of Sars-Cov-2, human-induced pluripotent stem cells (hiPSC), and a culture device made of an arrayed monolayer of cross-linked nanofibers. hiPSCs are first differentiated into CMs that form cardiac tissue-like constructs with regular beating and expression of both ACE2 and gap junction protein Connexin 43. When incubated with the spike proteins, the hiPSC-CMs undergo a rhythmic fluctuation with overstretched sarcomere structures and dispersed gap junction proteins. When incubated with the spike proteins and supplementary angiotensin II, the damage of the spike protein on hiPSC-CMs is enhanced due to downregulated ACE2, chromatin margination, altered Connexin 43 expression, sarcomere disruption, and beating break. This discovery may imply latent effects of the spike proteins on the heart.

17.
Acta Medica Iranica ; 60(4):202-209, 2022.
Article in English | Academic Search Complete | ID: covidwho-1824333

ABSTRACT

The coronavirus disease 2019 (COVID-19) is a single-stranded RNA (+) virus and causes infectious disease by the viral strain "severe acute respiratory syndrome coronavirus 2" (SARS-CoV-2). Now, COVID-19 has become pandemic, and there are neither potential vaccines nor drugs discovered. Its RNA contains genes for structural (S, E, M, N) and non-structural proteins (PLpro, 3CLpro, RdRp, Hel). Interaction between the S protein of SARS-CoV-2 and the ACE 2 receptor of the host cell plays a vital role in the entry of the virus into the cell. Favipiravir, ribavirin, remdesivir, galidesivir, lopinavir, ritonavir, chloroquine, and hydroxychloroquine are the few effective drugs against SARS-CoV-2. Live attenuated virus (mutant MERS-CoV and SARS-CoV or recombination with another live attenuated virus) can act as vaccine platforms against SARS CoV-2 along with DNA vaccine and subunit vaccine. [ FROM AUTHOR] Copyright of Acta Medica Iranica is the property of Tehran University of Medical Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

18.
Journal of the Mexican Chemical Society ; 66(2):181-197, 2022.
Article in English | Web of Science | ID: covidwho-1822721

ABSTRACT

The ongoing coronavirus disease 2019 (COVID-19) has become a global pandemic and risk to the healthcare system of almost every nation around the world. The endocytic pathway has been considered as a key factor in viral infection. In the case of CoVs, several investigations have shown that these viruses mainly follow the clathrin-mediated endocytic pathway. As a result, inhibiting the clathrin-mediated endocytic pathway might be a useful therapeutic approach. In this study, bioactive components of Harsingar, Meethi neem, Tulsi and Ashwagandha extract was analyzed by HR-LCMS and among them 55 phytochemical compounds were selected based on antiviral and steroidal properties. 55 phytochemical compounds of four Indian herbal plants were used to analyze their binding with clathrin protein associated with COVID-19. Based on the molecular docking as well as ADMET analysis, Ashwagandha, Harsingar, Meethi neem and Tulsi were identified as potential herbal medicine candidates. We have found that the inhibition potentials of the Ashwagandha, Harsingar, Meethi neem and Tulsi are very promising with no side effects.

19.
Natural Product Communications ; 17(4), 2022.
Article in English | EMBASE | ID: covidwho-1822124

ABSTRACT

Background: Coronavirus disease 2019 (COVID-19) has posed a serious threat to human health and there is an urgent need for drug development. In this study, we explored the potential mechanisms underlying the efficacy of polydatin against COVID-19. Methods: A combined approach of network pharmacology, molecular docking, and experimental verification were employed in this study. Potential targets of polydatin for treating COVID-19 were obtained from multiple drug and disease databases. Protein–protein interaction and enrichment analyses were performed to predict the potential mechanism of action of polydatin against COVID-19. The binding potential of polydatin and key targets was evaluated through molecular docking. Furthermore, experimental methods including flow cytometry and luciferase assay were used to validate the results of computational analyses. Results: The main diseases identified as polydatin targets included metabolic diseases, lung diseases, inflammation, infectious diseases, and tumors. Polydatin may be used to treat COVID-19 through interventions that alter the immune and inflammatory responses, including IL-17 signaling pathway, T-cell activation, cytokines and inflammatory response, lipopolysaccharide-mediated signaling pathway, as well as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) innate immunity evasion and cell-specific immune response. Polydatin can potentially bind to the target proteins related to COVID-19, such as SARS-CoV-2 Mpro, RdRp, and human angiotensin-converting enzyme 2 (ACE2), while directly exerting its regulatory or therapeutic functions. The experimental results showed that polydatin decreased the infectivity of the SARS-CoV-2 spike pseudovirus in HEK293T-ACE2 cells. Accordingly, polydatin may retard the entry of SARS-CoV-2 into cells by competitively binding to human ACE2. Conclusion: The potential targets and signaling pathways of polydatin against COVID-19 were preliminarily identified. The findings may benefit the development and application of polydatin as a treatment for COVID-19.

20.
Front Microbiol ; 13: 879152, 2022.
Article in English | MEDLINE | ID: covidwho-1822383

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the cause of the COVID-19 pandemic, is initiated by its binding to the ACE2 receptor and other co-receptors on mucosal epithelial cells. Variable outcomes of the infection and disease severity can be influenced by pre-existing risk factors. Human immunodeficiency virus (HIV), the cause of AIDS, targets the gut mucosal immune system and impairs epithelial barriers and mucosal immunity. We sought to determine the impact and mechanisms of pre-existing HIV infection increasing mucosal vulnerability to SARS-CoV-2 infection and disease. We investigated changes in the expression of ACE2 and other SARS-CoV-2 receptors and related pathways in virally inflamed gut by using the SIV infected rhesus macaque model of HIV/AIDS. Immunohistochemical analysis showed sustained/enhanced ACE2 expression in the gut epithelium of SIV infected animals compared to uninfected controls. Gut mucosal transcriptomic analysis demonstrated enhanced expression of host factors that support SARS-CoV-2 entry, replication, and infection. Metabolomic analysis of gut luminal contents revealed the impact of SIV infection as demonstrated by impaired mitochondrial function and decreased immune response, which render the host more vulnerable to other pathogens. In summary, SIV infection resulted in sustained or increased ACE2 expression in an inflamed and immune-impaired gut mucosal microenvironment. Collectively, these mucosal changes increase the susceptibility to SARS-CoV-2 infection and disease severity and result in ineffective viral clearance. Our study highlights the use of the SIV model of AIDS to fill the knowledge gap of the enteric mechanisms of co-infections as risk factors for poor disease outcomes, generation of new viral variants and immune escape in COVID-19.

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