title: Antiviral activities of 15 dengue NS2B-NS3 protease inhibitors using a human cell-based viral quantification assay.
abstract: The dengue virus is a mosquito-borne pathogen responsible for an estimated 50-100 million human dengue infections annually. There are currently no approved drugs against this disease, resulting in a major unmet clinical need. The dengue viral NS2B-NS3 protease has been identified as a plausible drug target due to its involvement in viral replication in mammalian host cells. In the past decade, at least 20 dengue NS2B-NS3 protease inhibitors have been reported in the literature with a range of inhibitory activities in protease assays. However, such assays do not shed light on an inhibitor's ability to penetrate human cell membranes where the viral protease resides. In this study, we investigated the antiviral activities of 15 small-molecule and peptide-based NS2B-NS3 inhibitors on dengue serotype 2-infected HuH-7 human hepatocarcinoma cells. Experimental results revealed anthraquinone ARDP0006 (compound 5) to be the most potent inhibitor which reduced dengue viral titer by more than 1 log PFU/mL at 1 μM in our cell-based assays involving HuH-7 and K562 cell lines, suggesting that its scaffold could serve as a lead for further medicinal chemistry studies. Compound 5 was also found to be non-cytotoxic at 1 μM over 3 days incubation on HuH-7 cells using the Alamar Blue cellular toxicity assay.
authors.affiliation: Laboratory of Molecular RNA Virology and Antiviral Strategies, Department of Microbiology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore 117597, Singapore. Electronic address: miccjh@nus.edu.sg.
authors.forename: Justin Jang Hann
authors.initials: JJ
authors.lastname: Chu
authors.affiliation: Laboratory of Molecular RNA Virology and Antiviral Strategies, Department of Microbiology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore 117597, Singapore.
authors.forename: Regina Ching Hua
authors.initials: RC
authors.lastname: Lee
authors.affiliation: Experimental Therapeutics Centre, Agency for Science, Technology and Research (A(∗)STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore.
authors.forename: Melgious Jin Yan
authors.initials: MJ
authors.lastname: Ang
authors.affiliation: Experimental Therapeutics Centre, Agency for Science, Technology and Research (A(∗)STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore.
authors.forename: Wei-Ling
authors.initials: WL
authors.lastname: Wang
authors.affiliation: Experimental Therapeutics Centre, Agency for Science, Technology and Research (A(∗)STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore.
authors.forename: Huichang Annie
authors.initials: HA
authors.lastname: Lim
authors.affiliation: Experimental Therapeutics Centre, Agency for Science, Technology and Research (A(∗)STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore.
authors.forename: John Liang Kuan
authors.initials: JL
authors.lastname: Wee
authors.affiliation: Experimental Therapeutics Centre, Agency for Science, Technology and Research (A(∗)STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore.
authors.forename: Joma
authors.initials: J
authors.lastname: Joy
authors.affiliation: Experimental Therapeutics Centre, Agency for Science, Technology and Research (A(∗)STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Hill
authors.affiliation: Experimental Therapeutics Centre, Agency for Science, Technology and Research (A(∗)STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore. Electronic address: cschia@etc.a-star.edu.sg.
authors.forename: C S
authors.initials: CS
authors.lastname: Brian Chia
mesh_terms: D000880:Anthraquinones / Q000494:pharmacology* / Q000633:toxicity; D000998:Antiviral Agents / Q000494:pharmacology* / Q000633:toxicity; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003716:Dengue Virus / Q000187:drug effects / Q000201:enzymology* / Q000502:physiology; D022781:Hepatocytes / Q000187:drug effects / Q000821:virology; D006801:Humans; D008826:Microbial Sensitivity Tests; D011480:Protease Inhibitors / Q000494:pharmacology* / Q000633:toxicity; D020365:RNA Helicases / Q000037:antagonists & inhibitors; D012697:Serine Endopeptidases; D019562:Viral Load; D017361:Viral Nonstructural Proteins / Q000037:antagonists & inhibitors*; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases
chemical_list: D000880:Anthraquinones; D000998:Antiviral Agents; D011480:Protease Inhibitors; D020365:RNA Helicases; D012697:Serine Endopeptidases; D017361:Viral Nonstructural Proteins; C080102:NS2B protein, flavivirus; C060028:NS3 protein, flavivirus; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases
keywords: Antiviral; Dengue; NS2B-NS3; Protease inhibitor