N -Desmethylclozapine, Fluoxetine, and Salmeterol Inhibit Postentry Stages of the Dengue Virus Life Cycle

Abstract

Around 10,000 people die each year due to severe dengue disease, and two-thirds of the world population lives in a region where dengue disease is endemic. There has been remarkable progress in dengue virus vaccine development; however, there are no licensed antivirals for dengue disease, and none appear to be in clinical trials. We took the approach of repositioning approved drugs for anti-dengue virus activity by screening a library of pharmacologically active compounds. We identified N-desmethylclozapine, fluoxetine hydrochloride, and salmeterol xinafoate as dengue virus inhibitors based on reductions in the numbers of infected cells and viral titers. Dengue virus RNA levels were diminished in inhibitor-treated cells, and this effect was specific to dengue virus, as other flaviviruses, such as Japanese encephalitis virus and West Nile virus, or other RNA viruses, such as respiratory syncytial virus and rotavirus, were not affected by these inhibitors. All three inhibitors specifically inhibited dengue virus replication with 50% inhibitory concentrations (IC50s) in the high-nanomolar range. Estimation of negative-strand RNA intermediates and time-of-addition experiments indicated that inhibition was occurring at a postentry stage, most probably at the initiation of viral RNA replication. Finally, we show that inhibition is most likely due to the modulation of the endolysosomal pathway and induction of autophagy.

Dengue Virus Capsid Interacts with DDX3X–A Potential Mechanism for Suppression of Antiviral Functions in Dengue Infection

“…We speculate that DDX3X may mediate anti-viral effects independent of IFN-β response by other stress response pathways. We have shown recently that drugs that induced autophagy acted as potent inhibitors of DENV replication (Medigeshi et al, 2016 ). Therefore, it would be interesting to investigate the role of DDX3X in autophagy.…”

“…All the cell lines, virus strain used in this study and virus titering protocols have been described previously (Agrawal et al, 2013 ; Medigeshi et al, 2016 ). Huh-7, HEK293T, A549 cells were grown in Dulbecco's modified Eagle medium (DMEM) supplemented with 10% fetal bovine serum (FBS), 1 mM L-glutamine, 100 units/ml penicillin-streptomycin-glutamine and non-essential amino acids at 37°C and 5% CO2.…”

Zinc Chelation Specifically Inhibits Early Stages of Dengue Virus Replication by Activation of NF-κB and Induction of Antiviral Response in Epithelial Cells

“…Caco-2, A549, Huh-7, BHK-21, C6/36, HEp-2, PS, and MA104 cells were cultured as described previously (15)(16)(17). Virus strains used in the study and infection procedures has been described before (15)(16)(17). DENV-2 New Guinea C strain was a kind gift from Dr. Navin Khanna.…”

“…Most of the experiments have been performed in both the cell lines and we have obtained similar results. Plaque assay for DENV, JEV, and RV was set up in BHK-21, PS, and MA 104 cells respectively as described previously (15)(16)(17).…”

Dengue Virus and Its Inhibitors: A Brief Review

“…99) Lee et al evaluated the anti-DENV2 effect of a cocktail of aqueous extracts from four Phyllanthus spp., and found that that the cocktail altered the expression of 13 regulatory viral and host proteins that act on viral attachment, viral entry, polyprotein production, replication, assembly, and maturation. 100) The molecular mechanism and the effect on other serotypes were not reported.…”