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1.
2023 IEEE International Conference on Integrated Circuits and Communication Systems, ICICACS 2023 ; 2023.
Article in English | Scopus | ID: covidwho-2326300

ABSTRACT

The heterotypic perspective of cancer depicts solid tumors as ecosystems composed of aberrant epithelium tumor cells and a multitude of cell types together referred to as stromal cells. Macrophages, which are innate immune cells, are overrepresented in certain environments. Tumor-associated macrophages (TAMs) are macrophages found in the tumor microenvironment;they are derived from the blood's monocytes and are essential for tumor progression. TAMs acquiring tumorigenic qualities is dependent on a complicated interaction between TAMs and tumor cells. Using co-culture studies, we showed that tumor-derived secretory signals promote Tams' tumor-promoting characteristics, shaping up Tams' features in ways that are advantageous to the tumor. When model human monocytes (THP-1) were co-cultured with A549 cells, the A549 cells exhibited increased proliferation, migration, and invasiveness due to the secretion of tumor-promoting cytokines from the THP-1 cells. We showed that EDA-containing Fibronectin secreted by A549 cells reliably mediates the pro-inflammatory response of THP-1 monocytes in a paracrine manner. Ablation of such responses by the treatment of THP-1 cells with TLR-4 blocking antibody implicated Fibronectin-TLR4 axis in tumor-associated inflammation and suggests a paradigm wherein lung carcinoma cell derived EDA-containing Fibronectin drives a pro-inflammatory and pro-metastatic tumor microenvironment. Interestingly, autocrine proliferation, migration, and invasion were all boosted by EDA-containing Fibronectin secreted by A549 cells. Lastly, we demonstrated that the EDA in Fibronectin activates the epithelial-mesenchymal transition pathway in A549 cells, hence granting these cells the ability to metastasize. © 2023 IEEE.

2.
COVID ; 2(11): 1551-1563, 2022 Nov.
Article in English | MEDLINE | ID: covidwho-2090030

ABSTRACT

Coronavirus disease 2019 (COVID-19) has had devastating effects worldwide, with particularly high morbidity and mortality in outbreaks on residential care facilities. Amantadine, originally licensed as an antiviral agent for therapy and prophylaxis against influenza A virus, has beneficial effects on patients with Parkinson's disease and is used for treatment of Parkinson's disease, multiple sclerosis, acquired brain injury, and various other neurological disorders. Recent observational data suggest an inverse relationship between the use of amantadine and COVID-19. Adamantanes, including amantadine and rimantadine, are reported to have in vitro activity against severe acute respiratory syndrome coronavirus (SARS-CoV) and, more recently, SARS-CoV-2. We hypothesized that adamantanes have antiviral activity against SARS-CoV-2, including variant strains. To assess the activity of adamantanes against SARS-CoV-2, we used in vitro and in vivo models of infection. We established that amantadine, rimantadine, and tromantadine inhibit the growth of SARS-CoV-2 in vitro in cultured human epithelial cells. While neither rimantadine nor amantadine reduces lung viral titers in mice infected with mouse-adapted SARS-CoV-2, rimantadine significantly reduces viral titers in the lungs in golden Syrian hamsters infected with SARS-CoV-2. In summary, rimantadine has antiviral activity against SARS-CoV-2 in human alveolar epithelial cells and in the hamster model of SARS-CoV-2 lung infection. The evaluation of amantadine or rimantadine in human randomized controlled trials can definitively address applications for the treatment or prevention of COVID-19.

3.
Microorganisms ; 10(10)2022 Oct 10.
Article in English | MEDLINE | ID: covidwho-2071644

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic began in January 2020 in Wuhan, China, with a new coronavirus designated SARS-CoV-2. The principal cause of death from COVID-19 disease quickly emerged as acute respiratory distress syndrome (ARDS). A key ARDS pathogenic mechanism is the "Cytokine Storm", which is a dramatic increase in inflammatory cytokines in the blood. In the last two years of the pandemic, a new pathology has emerged in some COVID-19 survivors, in which a variety of long-term symptoms occur, a condition called post-acute sequelae of COVID-19 (PASC) or "Long COVID". Therefore, there is an urgent need to better understand the mechanisms of the virus. The spike protein on the surface of the virus is composed of joined S1-S2 subunits. Upon S1 binding to the ACE2 receptor on human cells, the S1 subunit is cleaved and the S2 subunit mediates the entry of the virus. The S1 protein is then released into the blood, which might be one of the pivotal triggers for the initiation and/or perpetuation of the cytokine storm. In this study, we tested the hypothesis that the S1 spike protein is sufficient to activate inflammatory signaling and cytokine production, independent of the virus. Our data support a possible role for the S1 spike protein in the activation of inflammatory signaling and cytokine production in human lung and intestinal epithelial cells in culture. These data support a potential role for the SARS-CoV-2 S1 spike protein in COVID-19 pathogenesis and PASC.

4.
Int J Mol Sci ; 23(16)2022 Aug 22.
Article in English | MEDLINE | ID: covidwho-1997648

ABSTRACT

The aims of our study are to: (i) investigate the ability of nicotine to modulate the expression level of inflammatory cytokines in A549 cells infected with SARS-CoV-2; (ii) elucidate the ultrastructural features caused by the combination nicotine+SARS-CoV-2; and (iii) demonstrate the mechanism of action. In this study, A549 cells pretreated with nicotine were either exposed to LPS or poly(I:C), or infected with SARS-CoV-2. Treated and untreated cells were analyzed for cytokine production, cytotoxicity, and ultrastructural modifications. Vero E6 cells were used as a positive reference. Cells pretreated with nicotine showed a decrease of IL6 and TNFα in A549 cells induced by LPS or poly(I:C). In contrast, cells exposed to SARS-CoV-2 showed a high increase of IL6, IL8, IL10 and TNFα, high cytopathic effects that were dose- and time-dependent, and profound ultrastructural modifications. These modifications were characterized by membrane ruptures and fragmentation, the swelling of cytosol and mitochondria, the release of cytoplasmic content in extracellular spaces (including osmiophilic granules), the fragmentation of endoplasmic reticulum, and chromatin disorganization. Nicotine increased SARS-CoV-2 cytopathic effects, elevating the levels of inflammatory cytokines, and inducing severe cellular damage, with features resembling pyroptosis and necroptosis. The protective role of nicotine in COVID-19 is definitively ruled out.


Subject(s)
Nicotine , SARS-CoV-2 , A549 Cells , COVID-19 , Cell Survival/drug effects , Cytokines/metabolism , Humans , Interleukin-6 , Lipopolysaccharides , Nicotine/adverse effects , Nicotine/pharmacology , Tumor Necrosis Factor-alpha
5.
Mar Drugs ; 19(2)2021 Jan 27.
Article in English | MEDLINE | ID: covidwho-1969360

ABSTRACT

Inorganic polyphosphate (polyP) is a widely distributed polymer found from bacteria to animals, including marine species. This polymer exhibits morphogenetic as well as antiviral activity and releases metabolic energy after enzymatic hydrolysis also in human cells. In the pathogenesis of the coronavirus disease 2019 (COVID-19), the platelets are at the frontline of this syndrome. Platelets release a set of molecules, among them polyP. In addition, the production of airway mucus, the first line of body defense, is impaired in those patients. Therefore, in this study, amorphous nanoparticles of the magnesium salt of polyP (Mg-polyP-NP), matching the size of the coronavirus SARS-CoV-2, were prepared and loaded with the secondary plant metabolite quercetin or with dexamethasone to study their effects on the respiratory epithelium using human alveolar basal epithelial A549 cells as a model. The results revealed that both compounds embedded into the polyP nanoparticles significantly increased the steady-state-expression of the MUC5AC gene. This mucin species is the major mucus glycoprotein present in the secreted gel-forming mucus. The level of gene expression caused by quercetin or with dexamethasone, if caged into polyP NP, is significantly higher compared to the individual drugs alone. Both quercetin and dexamethasone did not impair the growth-supporting effect of polyP on A549 cells even at concentrations of quercetin which are cytotoxic for the cells. A possible mechanism of the effects of the two drugs together with polyP on mucin expression is proposed based on the scavenging of free oxygen species and the generation of ADP/ATP from the polyP, which is needed for the organization of the protective mucin-based mucus layer.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Dexamethasone/pharmacology , Mucin 5AC/biosynthesis , Mucin 5AC/drug effects , Quercetin/pharmacology , A549 Cells , Anti-Inflammatory Agents/chemistry , Antioxidants/chemistry , COVID-19 , Dexamethasone/chemistry , Free Radical Scavengers/pharmacology , Gene Expression Regulation/drug effects , Humans , Magnesium/chemistry , Mucin 5AC/genetics , Mucins/biosynthesis , Mucins/chemistry , Nanoparticles , Particle Size , Plants/chemistry , Polyphosphates/chemistry , Quercetin/chemistry , Reactive Oxygen Species
6.
Molecules ; 26(21)2021 Oct 23.
Article in English | MEDLINE | ID: covidwho-1512507

ABSTRACT

Tuberculosis (TB) is an infectious disease that causes a great number of deaths in the world (1.5 million people per year). This disease is currently treated by administering high doses of various oral anti-TB drugs for prolonged periods (up to 2 years). While this regimen is normally effective when taken as prescribed, many people with TB experience difficulties in complying with their medication schedule. Furthermore, the oral administration of standard anti-TB drugs causes severe side effects and widespread resistances. Recently, we proposed an original platform for pulmonary TB treatment consisting of mannitol microspheres (Ma MS) containing iron (III) trimesate metal-organic framework (MOF) MIL-100 nanoparticles (NPs). In the present work, we loaded this system with the first-line anti-TB drug isoniazid (INH) and evaluated both the viability and safety of the drug vehicle components, as well as the cell internalization of the formulation in alveolar A549 cells. Results show that INH-loaded MOF (INH@MIL-100) NPs were efficiently microencapsulated in Ma MS, which displayed suitable aerodynamic characteristics for pulmonary administration and non-toxicity. MIL-100 and INH@MIL-100 NPs were efficiently internalized by A549 cells, mainly localized in the cytoplasm. In conclusion, the proposed micro-nanosystem is a good candidate for the pulmonary administration of anti-TB drugs.


Subject(s)
Antitubercular Agents/pharmacology , Isoniazid/pharmacology , Metal-Organic Frameworks/pharmacology , Tuberculosis, Pulmonary/drug therapy , A549 Cells , Administration, Inhalation , Antitubercular Agents/administration & dosage , Antitubercular Agents/chemistry , Capsules/administration & dosage , Capsules/chemistry , Capsules/pharmacology , Cell Survival/drug effects , Dose-Response Relationship, Drug , Humans , Isoniazid/administration & dosage , Isoniazid/chemistry , Metal-Organic Frameworks/administration & dosage , Metal-Organic Frameworks/chemistry , Particle Size
7.
Antimicrob Agents Chemother ; 65(7): e0009721, 2021 06 17.
Article in English | MEDLINE | ID: covidwho-1486469

ABSTRACT

Efforts to mitigate the coronavirus disease 2019 (COVID-19) pandemic include the screening of existing antiviral molecules that could be repurposed to treat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Although SARS-CoV-2 replicates and propagates efficiently in African green monkey kidney (Vero) cells, antivirals such as nucleos(t)ide analogs (NUCs) often show decreased activity in these cells due to inefficient metabolization. SARS-CoV-2 exhibits low viability in human cells in culture. Here, serial passages of a SARS-CoV-2 isolate (original-SARS2) in the human hepatoma cell clone Huh7.5 led to the selection of a variant (adapted-SARS2) with significantly improved infectivity in human liver (Huh7 and Huh7.5) and lung cancer (unmodified Calu-1 and A549) cells. The adapted virus exhibited mutations in the spike protein, including a 9-amino-acid deletion and 3 amino acid changes (E484D, P812R, and Q954H). E484D also emerged in Vero E6-cultured viruses that became viable in A549 cells. Original and adapted viruses were susceptible to scavenger receptor class B type 1 (SR-B1) receptor blocking, and adapted-SARS2 exhibited significantly less dependence on ACE2. Both variants were similarly neutralized by COVID-19 convalescent-phase plasma, but adapted-SARS2 exhibited increased susceptibility to exogenous type I interferon. Remdesivir inhibited original- and adapted-SARS2 similarly, demonstrating the utility of the system for the screening of NUCs. Among the tested NUCs, only remdesivir, molnupiravir, and, to a limited extent, galidesivir showed antiviral effects across human cell lines, whereas sofosbuvir, ribavirin, and favipiravir had no apparent activity. Analogously to the emergence of spike mutations in vivo, the spike protein is under intense adaptive selection pressure in cell culture. Our results indicate that the emergence of spike mutations will most likely not affect the activity of remdesivir.


Subject(s)
COVID-19 , SARS-CoV-2 , Antiviral Agents/pharmacology , Chlorocebus aethiops , Humans , Pandemics , Spike Glycoprotein, Coronavirus , Virus Replication
8.
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
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