scholarly journals SARS-CoV-2-mediated dysregulation of metabolism and autophagy uncovers host-targeting antivirals

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Nils C. Gassen ◽  
Jan Papies ◽  
Thomas Bajaj ◽  
Jackson Emanuel ◽  
Frederik Dethloff ◽  
...  
Keyword(s):  
Disease Duration ◽  
Treatment Options ◽  
Cellular Metabolism ◽  
Hamster Model ◽  
Immune Genes ◽  
Single Cell Sequencing ◽  
Human Lung Cells ◽  
Infected Cells ◽  
Single Nucleus

AbstractViruses manipulate cellular metabolism and macromolecule recycling processes like autophagy. Dysregulated metabolism might lead to excessive inflammatory and autoimmune responses as observed in severe and long COVID-19 patients. Here we show that SARS-CoV-2 modulates cellular metabolism and reduces autophagy. Accordingly, compound-driven induction of autophagy limits SARS-CoV-2 propagation. In detail, SARS-CoV-2-infected cells show accumulation of key metabolites, activation of autophagy inhibitors (AKT1, SKP2) and reduction of proteins responsible for autophagy initiation (AMPK, TSC2, ULK1), membrane nucleation, and phagophore formation (BECN1, VPS34, ATG14), as well as autophagosome-lysosome fusion (BECN1, ATG14 oligomers). Consequently, phagophore-incorporated autophagy markers LC3B-II and P62 accumulate, which we confirm in a hamster model and lung samples of COVID-19 patients. Single-nucleus and single-cell sequencing of patient-derived lung and mucosal samples show differential transcriptional regulation of autophagy and immune genes depending on cell type, disease duration, and SARS-CoV-2 replication levels. Targeting of autophagic pathways by exogenous administration of the polyamines spermidine and spermine, the selective AKT1 inhibitor MK-2206, and the BECN1-stabilizing anthelmintic drug niclosamide inhibit SARS-CoV-2 propagation in vitro with IC50 values of 136.7, 7.67, 0.11, and 0.13 μM, respectively. Autophagy-inducing compounds reduce SARS-CoV-2 propagation in primary human lung cells and intestinal organoids emphasizing their potential as treatment options against COVID-19.

scholarly journals Clofazimine is a broad-spectrum coronavirus inhibitor that antagonizes SARS-CoV-2 replication in primary human cell culture and hamsters

2020 ◽  
Author(s):  
Shuofeng Yuan ◽  
Xin Yin ◽  
XiangZhi Meng ◽  
Jasper Chan ◽  
Zi-Wei Ye ◽  
...  
Keyword(s):  
Middle East ◽  
Ex Vivo ◽  
Treatment Options ◽  
Embryonic Stem ◽  
Manufacturing Cost ◽  
Hamster Model ◽  
Viral Shedding ◽  
Orally Bioavailable ◽  
Favorable Safety

Abstract COVID-19 pandemic is the third zoonotic coronavirus (CoV) outbreak of the century after severe acute respiratory syndrome (SARS) in 2003 and Middle East respiratory syndrome (MERS) since 2012. Treatment options for CoVs are largely lacking. Here, we show that clofazimine, an anti-leprosy drug with a favorable safety and pharmacokinetics profile, possesses pan-coronaviral inhibitory activity, and can antagonize SARS-CoV-2 replication in multiple in vitro systems, including the human embryonic stem cell-derived cardiomyocytes and ex vivo lung cultures. The FDA-approved molecule was found to inhibit multiple steps of viral replication, suggesting multiple underlying antiviral mechanisms. In a hamster model of SARS-CoV-2 pathogenesis, prophylactic or therapeutic administration of clofazimine significantly reduced viral load in the lung and fecal viral shedding, and also prevented cytokine storm associated with viral infection. Additionally, clofazimine exhibited synergy when administered with remdesivir. Since clofazimine is orally bioavailable and has a comparatively low manufacturing cost, it is an attractive clinical candidate for outpatient treatment and remdesivir-based combinatorial therapy for hospitalized COVID-19 patients, particularly in developing countries. Taken together, our data provide evidence that clofazimine may have a role in the control of the current pandemic SARS-CoV-2, endemic MERS-CoV in the Middle East, and, possibly most importantly, emerging CoVs of the future.

scholarly journals Development of a Novel Formulation with Hypericin To Treat Cutaneous Leishmaniasis Based on Photodynamic Therapy inIn VitroandIn VivoStudies

2015 ◽  
Vol 59 (9) ◽  
pp. 5804-5813 ◽  
Author(s):  
Andrés Montoya ◽  
Alejandro Daza ◽  
Diana Muñoz ◽  
Karina Ríos ◽  
Viviana Taylor ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Cutaneous Leishmaniasis ◽  
Hypericum Perforatum ◽  
Topical Formulation ◽  
Hamster Model ◽  
Content Type ◽  
Intracellular Amastigotes ◽  
Infected Cells

ABSTRACTAn evaluation of the leishmanicidal activityin vitroandin vivoof hypericin, an expanded-spectrum photosensitizer found inHypericum perforatum, is presented. Hypericin was evaluated against intracellular amastigotesin vitroofLeishmania(Viannia)panamensis. A topical formulation containing 0.5% hypericin was developed and assayedin vivoin a hamster model of cutaneous leishmaniasis. Results demonstrate that hypericin induces a significant antiamastigote effectin vitroagainstL. panamensisby decreasing the number of parasites inside infected cells. The topical formulation of 0.5% hypericin allows healing ofL. panamensis-induced lesions upon a topical application of 40 mg/day plus visible-light irradiation (5 J/cm2, 15 min), twice a week for 3 weeks.

scholarly journals Targeted mutations in a highly conserved motif of the nsp1β protein impair the interferon antagonizing activity of porcine reproductive and respiratory syndrome virus

2013 ◽  
Vol 94 (9) ◽  
pp. 1972-1983 ◽  
Author(s):  
Yanhua Li ◽  
Longchao Zhu ◽  
Steven R. Lawson ◽  
Ying Fang
Keyword(s):  
Gene Expression ◽  
Reverse Genetics ◽  
Innate Immune ◽  
Respiratory Syndrome Virus ◽  
Structural Protein ◽  
Virus Growth ◽  
Conserved Motif ◽  
Immune Genes ◽  
Infected Cells

Non-structural protein 1β (nsp1β) of porcine reproductive and respiratory syndrome virus (PRRSV) contains a papain-like cysteine protease (PLPβ) domain and has been identified as the main viral protein antagonizing the host innate immune response. In this study, nsp1β was determined to suppress the expression of reporter genes as well as to suppress ‘self-expression’ in transfected cells, and this activity appeared to be associated with its interferon (IFN) antagonist function. To knock down the effect of nsp1β on IFN activity, a panel of site-specific mutations in nsp1β was analysed. Double mutations K130A/R134A (type 1 PRRSV) or K124A/R128A (type 2 PRRSV) targeting a highly conserved motif of nsp1β, GKYLQRRLQ (in bold), impaired the ability of nsp1β to suppress IFN-β and reporter gene expression, as well as to suppress ‘self-expression’ in vitro. Subsequently, viable recombinant viruses vSD01-08-K130A/R134A and vSD95-21-K124A/R128A, containing double mutations in the GKYLQRRLQ motif were generated using reverse genetics. In comparison with WT viruses, these nsp1β mutants showed impaired growth ability in infected cells, but the PLPβ cleavage function was not directly affected. The expression of selected innate immune genes was determined in vSD95-21-K124A/R128A mutant-infected cells. The results consistently showed that gene expression levels of IFN-α, IFN-β and IFN-stimulated gene 15 were upregulated in cells that were infected with the vSD95-21-K124A/R128A compared with that of WT virus. These data suggest that PRRSV nsp1β may selectively suppress cellular gene expression, including expression of genes involved in the host innate immune function. Modifying the key residues in the highly conserved GKYLQRRLQ motif could attenuate virus growth and improve the cellular innate immune responses.

scholarly journals Complement Inhibitors Vitronectin and Clusterin Are Recruited from Human Serum to the Surface of Coronavirus OC43-Infected Lung Cells through Antibody-Dependent Mechanisms

Viruses ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 29
Author(s):  
Candace R. Fox ◽  
Griffith D. Parks
Keyword(s):  
Human Serum ◽  
Membrane Attack Complex ◽  
Health Concern ◽  
Lung Cells ◽  
Complement Inhibitors ◽  
Human Lung Cells ◽  
Infected Cells ◽  
Human Coronaviruses ◽  
Necessary And Sufficient

Little is known about the role of complement (C’) in infections with highly prevalent circulating human coronaviruses such as OC43, a group of viruses of major public health concern. Treatment of OC43-infected human lung cells with human serum resulted in C3 deposition on their surfaces and generation of C5a, indicating robust C’ activation. Real-time cell viability assays showed that in vitro C’-mediated lysis of OC43 infected cells requires C3, C5 and C6 but not C7, and was substantially delayed as compared to rapid C’-mediated killing of parainfluenza virus type 5 (PIV5)-infected cells. In cells co-infected with OC43 and PIV5, C’-mediated lysis was delayed, similar to OC43 infected cells alone, suggesting that OC43 infection induced dominant inhibitory signals. When OC43-infected cells were treated with human serum, their cell surfaces contained both Vitronectin (VN) and Clusterin (CLU), two host cell C’ inhibitors that can alter membrane attack complex (MAC) formation and C’-mediated killing. VN and CLU were not bound to OC43-infected cells after treatment with antibody-depleted serum. Reconstitution experiments with purified IgG and VN showed that human antibodies are both necessary and sufficient for VN recruitment to OC43-infected lung cells–novel findings with implications for CoV pathogenesis.

scholarly journals Silencing of SARS-CoV-2 with modified siRNA-peptide dendrimer formulation

2021 ◽  
Author(s):  
Musa Khaitov ◽  
Alexandra Nikonova ◽  
Igor Shilovskiy ◽  
Ksenia Kozhikhova ◽  
Ilya Kofiadi ◽  
...  
Keyword(s):  
Unmet Need ◽  
Virus Titer ◽  
Firefly Luciferase ◽  
Luciferase Reporter ◽  
Luciferase Reporter Gene ◽  
Hamster Model ◽  
Infected Cells ◽  
Peptide Dendrimer

Background. First vaccines for prevention of Coronavirus disease 2019 (COVID-19) are becoming available but there is a huge and unmet need for specific forms of treatment. In this study we aimed to evaluate the potent anti-SARS-CoV-2 effect of siRNA both in vitro and in vivo. Methods. To identify most effective molecule out of a panel of 15 in silico designed siRNAs, an in vitro screening system based on vectors expressing SARS-CoV-2 genes fused with the firefly luciferase reporter gene and SARS-CoV-2-infected cells was used. The most potent siRNA, siR-7, was modified by Locked nucleic acids (LNAs) to obtain siR-7-EM with increased stability and was formulated with the peptide dendrimer KK-46 for enhancing cellular uptake to allow topical application by inhalation of the final formulation - siR-7-EM/KK-46. Using the Syrian Hamster model for SARS-CoV-2 infection the antiviral capacity of siR-7-EM/KK-46 complex was evaluated. Results. We identified the siRNA, siR-7, targeting SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) as the most efficient siRNA inhibiting viral replication in vitro. Moreover, we have shown that LNA-modification and complexation with the designed peptide dendrimer enhanced the antiviral capacity of siR-7 in vitro. We demonstrated significant reduction of virus titer and total lung inflammation in the animals exposed by inhalation of siR-7-EM/KK-46 in vivo. Conclusions. Thus, we developed a therapeutic strategy for COVID-19 based on inhalation of a modified siRNA-peptide dendrimer formulation.

scholarly journals Epigenetics in Food Allergy and Immunomodulation

Nutrients ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 4345
Author(s):  
José A. Cañas ◽  
Rafael Núñez ◽  
Anyith Cruz-Amaya ◽  
Francisca Gómez ◽  
María J. Torres ◽  
...  
Keyword(s):  
Food Allergy ◽  
Treatment Options ◽  
Allergic Diseases ◽  
Developed Countries ◽  
Epigenetic Mechanism ◽  
Diagnostic Tools ◽  
Epigenetic Mechanisms ◽  
Immune Genes ◽  
Dietary Components

Food allergy (FA) is an increasing problem worldwide and, over recent years, its prevalence is rising in developed countries. Nowadays, the immunological and cellular processes that occur in the allergic reactions are not fully understood, which hampers the development of in vitro diagnostic tools and further treatment options. Moreover, allergic diseases could be reinforced by environmental exposure and genetic modifications. Gene expression can be controlled by different epigenetic mechanisms like DNA methylation, histone modifications, and microRNAs. In addition, several environmental factors such as dietary components (vitamin D, butyrate, folic acid) are able to regulate this epigenetic mechanism. All these factors produce modifications in immune genes that could alter the development and function of immune cells, and therefore the etiology of the disease. Furthermore, these epigenetic mechanisms have also an influence on immunomodulation, which could explain sustained responsiveness or unresponsiveness during immunotherapy due to epigenetic modifications in key genes that induce tolerance in several FA. Thus, in this review we focus on the different epigenetic mechanisms that occur in FA and on the influence of several dietary components in these gene modifications.

scholarly journals The NF-κB transcriptional footprint is essential for SARS-CoV-2 replication

2021 ◽  
Author(s):  
Benjamin E. Nilsson-Payant ◽  
Skyler Uhl ◽  
Adrien Grimont ◽  
Ashley S. Doane ◽  
Phillip Cohen ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Large Scale ◽  
Cytokine Production ◽  
Antiviral Treatment ◽  
Treatment Options ◽  
Type I ◽  
Mortality And Morbidity ◽  
The World ◽  
Infected Cells

SARS-CoV-2, the etiological agent of COVID-19, is characterized by a delay in Type I interferon (IFN-I)-mediated antiviral defenses alongside robust cytokine production. Here we investigate the underlying molecular basis for this imbalance and implicate virus-mediated activation of NF-κB in the absence of other canonical IFN-I-related transcription factors. Epigenetic and single cell transcriptomic analyses show a selective NF-κB signature that was most prominent in infected cells. Disruption of NF-κB signaling through the silencing of the NF-κB transcription factors p65 or p50 resulted in loss of virus replication that was rescued upon reconstitution. These findings could be further corroborated with the use of NF-κB inhibitors, which reduced SARS-CoV-2 replication in vitro . These data suggest that the robust cytokine production in response to SARS-CoV-2, despite a diminished IFN-I response, is the product of a dependency on NF-κB for viral replication. IMPORTANCE The COVID-19 pandemic has caused significant mortality and morbidity around the world. Although effective vaccines have been developed, large parts of the world remain unvaccinated while new SARS-CoV-2 strains keep emerging. Furthermore, despite extensive efforts and large-scale drug screenings, no fully effective antiviral treatment options have been discovered yet. Therefore, it is of the utmost importance to gain a better understanding of essential factors driving SARS-CoV-2 replication in order to be able to develop novel approaches to target SARS-CoV-2 biology.

Treatment Options in COVID-19: The Role of Bioavailable Antiviral Ribonucleoside Analog on NHC in vitro

2020 ◽  
Author(s):  
Lara Bittmann
Keyword(s):  
World Health Organization ◽  
Clinical Picture ◽  
Treatment Options ◽  
World Health ◽  
Wuhan City ◽  
The World ◽  
Novel Coronavirus ◽  
Health Organization

On December 31, 2019, WHO was informed of cases of pneumonia of unknown cause in Wuhan City, China. A novel coronavirus was identified as the cause by Chinese authorities on January 7, 2020 and was provisionally named "2019-nCoV". This new Coronavirus causes a clinical picture which has received now the name COVID-19. The virus has spread subsequently worldwide and was explained on the 11th of March, 2020 by the World Health Organization to the pandemic.

IN VITRO DESTRUCTION OF LEISHMANIA DONOVANI INFECTED CELLS BY IMMUNE SERUM

1976 ◽  
Vol 4 (3-4) ◽  
pp. 207-211
Author(s):  
SHUN SHINBO ◽  
TAKATOSHI KOBAYAKAWA ◽  
HIROSHI ISHIYAMA ◽  
KAZUSHIGE MASUDA
Keyword(s):  
Leishmania Donovani ◽  
Immune Serum ◽  
Infected Cells

Are Carbonic Anhydrases Suitable Targets to Fight Protozoan Parasitic Diseases?

2019 ◽  
Vol 25 (39) ◽  
pp. 5266-5278 ◽  
Author(s):  
Katia D'Ambrosio ◽  
Claudiu T. Supuran ◽  
Giuseppina De Simone
Keyword(s):  
Drug Resistance ◽  
Animal Models ◽  
Carbonic Anhydrase ◽  
Drug Target ◽  
Treatment Options ◽  
Parasitic Diseases ◽  
Carbonic Anhydrases ◽  
Extensive Drug Resistance ◽  
Protozoan Infections

Protozoans belonging to Plasmodium, Leishmania and Trypanosoma genera provoke widespread parasitic diseases with few treatment options and many of the clinically used drugs experiencing an extensive drug resistance phenomenon. In the last several years, the metalloenzyme Carbonic Anhydrase (CA, EC 4.2.1.1) was cloned and characterized in the genome of these protozoa, with the aim to search for a new drug target for fighting malaria, leishmaniasis and Chagas disease. P. falciparum encodes for a CA (PfCA) belonging to a novel genetic family, the η-CA class, L. donovani chagasi for a β-CA (LdcCA), whereas T. cruzi genome contains an α-CA (TcCA). These three enzymes were characterized in detail and a number of in vitro potent and selective inhibitors belonging to the sulfonamide, thiol, dithiocarbamate and hydroxamate classes were discovered. Some of these inhibitors were also effective in cell cultures and animal models of protozoan infections, making them of considerable interest for the development of new antiprotozoan drugs with a novel mechanism of action.

Sign in / Sign up

Export Citation Format

Share Document