title: Flavone enhances dengue virus type-2 (NGC strain) infectivity and replication in vero cells.
abstract: This study investigates the effects of 2-phenyl-1-benzopyran-4-one (flavone) on DENV-2 infectivity in Vero cells. Virus adsorption and attachment and intracellular virus replication were investigated using a foci forming unit assay (FFUA) and quantitative RT-PCR, respectively. Addition of flavone (100 μg/mL) significantly increased the number of DENV-2 foci by 35.66% ± 1.52 and 49.66% ± 2.51 when added during and after virus adsorption to the Vero cells, respectively. The average foci size after 4 days of infection increased by 33% ± 2.11 and 89% ± 2.13. The DENV-2 specific RNA copy number in the flavone-treated infected cells increased by 6.41- and 23.1-fold when compared to the mock-treated infected cells. Flavone (100 μg/mL) did not promote or inhibit Vero cell proliferation. The CC₅₀ value of flavone against Vero cells was 446 µg/mL. These results suggest that flavone might enhance dengue virus replication by acting antagonistically towards flavonoids known to inhibit dengue virus replication.
authors.affiliation: Tropical Infectious Diseases Research and Education Center (TIDREC), Department of Medical Microbiology, Faculty of Medicine, University Malaya, Kuala Lumpur 50603, Malaysia.
authors.forename: Keivan
authors.initials: K
authors.lastname: Zandi
authors.forename: Rafidah
authors.initials: R
authors.lastname: Lani
authors.forename: Pooi-Fong
authors.initials: PF
authors.lastname: Wong
authors.forename: Boon-Teong
authors.initials: BT
authors.lastname: Teoh
authors.forename: Sing-Sin
authors.initials: SS
authors.lastname: Sam
authors.forename: Jefree
authors.initials: J
authors.lastname: Johari
authors.forename: Mohd Rais
authors.initials: MR
authors.lastname: Mustafa
authors.forename: Sazaly
authors.initials: S
authors.lastname: AbuBakar
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D002522:Chlorocebus aethiops; D003716:Dengue Virus / Q000235:genetics / Q000502:physiology*; D047309:Flavones / Q000494:pharmacology*; D012367:RNA, Viral / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D014709:Vero Cells; D014779:Virus Replication / Q000187:drug effects*
chemical_list: D047309:Flavones; D012367:RNA, Viral; C043562:flavone