Aim: Dengue is a severe epidemic disease caused by dengue virus (DENV) infection, for which no effective treatment is available. The protease complex, consisting of nonstructural protein 3 (NS3) and its cofactor NS2B, plays a pivotal role in the replication of DENV, thus may be a potential target for anti-DENV drugs. Here, we report a novel inhibitor of DENV2 NS2B/NS3 protease and its antiviral action.
Methods: An enzymatic inhibition assay was used for screening DENV2 NS2B/NS3 inhibitors. Cytotoxicity to BHK-21 cells was assessed with MTT assay. Antiviral activity was evaluated in BHK-21 cells transfected with Rlu-DENV-Rep. The molecular mechanisms of the antiviral action was analyzed using surface plasmon resonance, ultraviolet-visible spectral analysis and differential scanning calorimetry assays, as well as molecular docking analysis combined with site-directed mutagenesis.
Results: In our in-house library of old drugs (~1000 compounds), a topical hemostatic and antiseptic 2-hydroxy-3,5-bis[(4-hydroxy-2-methyl-5-sulfophenyl)methyl]-4-methyl-benzene-sulfonic acid (policresulen) was found to be a potent inhibitor of DENV2 NS2B/NS3 protease with IC50 of 0.48 μg/mL. Furthermore, policresulen inhibited DENV2 replication in BHK-21 cells with IC50 of 4.99 μg/mL, whereas its IC50 for cytotoxicity to BHK-21 cells was 459.45 μg/mL. Policresulen acted as a competitive inhibitor of the protease, and slightly affected the protease stability. Using biophysical technology-based assays and molecular docking analysis combined with site-directed mutagenesis, we demonstrated that the residues Gln106 and Arg133 of DENV2 NS2B/NS3 protease directly interacted with policresulen via hydrogen bonding.
Conclusion: Policresulen is a potent inhibitor of DENV2 NS2B/NS3 protease that inhibits DENV2 replication in BHK-21 cells. The binding mode of the protease and policresulen provides useful hints for designing new type of inhibitors against the protease.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4561973 | PMC |
http://dx.doi.org/10.1038/aps.2015.56 | DOI Listing |
Arch Virol
December 2024
Department of Medical Entomology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan.
Most members of the genus Orthonairovirus, represented by Crimean-Congo hemorrhagic fever virus and Nairobi sheep disease virus, are tick-borne, and some have become a public health concern in recent years. Here, we report the isolation and genetic and biological characterization of a new orthonairovirus, designated as "Iwanai Valley virus" (IWVV), from Ixodes ovatus ticks in Hokkaido, Japan. The amino acid sequence of the viral nucleoprotein (NP) was found to be 34-45% identical to those of known orthonairoviruses.
View Article and Find Full Text PDFHeliyon
December 2024
Energy Engineering, Division of Energy Science, Luleå University of Technology, 97187, Luleå, Sweden.
The study investigates the impact of incorporating Ni and Cu into the lattice of ZnO nanoparticles (NPs) to enhance their anticancer and antioxidant properties. Characterization techniques including pXRD, FTIR, UV-visible absorption spectroscopy, FESEM, and EDAX confirm the successful synthesis and structural modifications of Ni/Cu-ZnO NPs. Anticancer activity against breast cancer (MDA) and normal skin (BHK-21) cells reveals dose-dependent cytotoxicity, with Ni/Cu-ZnO NPs exhibiting higher efficacy against MDA cells while being less harmful to BHK-21 cells.
View Article and Find Full Text PDFViruses
November 2024
Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Centro de Investigaciones Médicas, Escuela de Medicina, Pontificia Universidad Católica de Chile, Marcoleta 391, Santiago 8330024, Chile.
(DENV) is an enveloped, positive sense, single-stranded RNA virus belonging to the . Translation initiation of the DENV mRNA (vRNA) can occur following a cap-dependent, 5'-3'end-dependent internal ribosome entry site (IRES)-independent or IRES-dependent mechanism. This study evaluated the activity of DENV IRES in BHK-21 cells and the role of the polypyrimidine-tract binding protein (PTB) isoforms PTB1, PTB2, and PTB4 as IRES-transacting factors (ITAFs) for the DENV IRES.
View Article and Find Full Text PDFBio Protoc
October 2024
Programme in Emerging Infectious Diseases, Duke-National University of Singapore Medical School, Singapore, Singapore.
Dengue virus (DENV), a common and prevalent mosquito-borne endemic disease, is caused by four serotypes (DENV-1-4) and has spread rapidly on a global scale over the past decade. A crucial step in the development of antiviral therapeutics requires the utilization of in vitro cell-based techniques, such as plaque assays and focus-forming assays (FFA) for virus quantification. Vero cells have been widely used for FFA and plaque assay; however, there are instances when their efficacy and efficiency in the detection of certain clinical DENV isolates are low.
View Article and Find Full Text PDFPharmaceutics
October 2024
Institute of Biomedical Systems and Biotechnology, Peter the Great Saint Petersburg Polytechnic University, 29 Politechnicheskaya St., 195251 Saint Petersburg, Russia.
The development of polymer-lipid hybrid nanoparticles (PLNs) is a promising area of research, as it can help increase the stability of cationic lipid carriers. Hybrid PLNs are core-shell nanoparticle structures that combine the advantages of both polymer nanoparticles and liposomes, especially in terms of their physical stability and biocompatibility. Natural polymers such as polyhydroxyalkanoate (PHA) can be used as a matrix for the PLNs' preparation.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!