Research on the indirect antiviral function of medicinal plant ingredient quercetin against grouper iridovirus infection

• Published in: Fish & shellfish immunology 2022-05, Vol.124, p.372-379
• Main Authors: Huang, Lin, Li, Mengmeng, Wei, Hongling, Yu, Qing, Huang, Shuaishuai, Wang, Taixia, Liu, Mingzhu, Li, Pengfei
• Format: Article
• Language: English
• Subjects: Animals; Antiviral Agents - pharmacology; Antiviral Agents - therapeutic use; Antiviral immune responses; Bass - genetics; DNA Virus Infections - veterinary; Fish Diseases; Grouper iridovirus; Indirect antiviral effects; Iridovirus; Plants, Medicinal; Quercetin; Quercetin - pharmacology; Ranavirus
• ISSN: 1050-4648; 1095-9947
• DOI: 10.1016/j.fsi.2022.04.013

Grouper iridovirus is a devastating pathogen that belongs to the genus Ranavirus. Based on the previous results that natural ingredient quercetin isolated from Illicium verum Hook. f. could effectively inhibit Singapore grouper iridovirus (SGIV) replication, suggesting that quercetin could serve as potential antiviral agent against grouper iridovirus. To know about whether quercetin has indirect antiviral activity against SGIV, this study made the investigation in vitro and in vivo, and the potential mechanism was also explored. Pretreating the cells with quercetin (12.5 μg/mL) significantly inhibited the replication of SGIV, similar results were also confirmed in vivo. Importantly, quercetin pretreatment could induce the expression of genes involved in type I interferon (IFN) system (IFN, STAT1, PKR, MxI and ISG15) and TLR9. It suggested that quercetin exerted the indirect antiviral activity against SGIV infection through promoting the recognition of SGIV and activating the IFN pathway to establish the antiviral status of host cell. Taken together, our results shedded light on the indirect antiviral function of natural ingredient quercetin, and clearly demonstrated that natural ingredient quercetin will be an excellent potential agent against SGIV infection in grouper aquaculture. •Quercetin pretreatment significantly inhibited the replication of SGIV in vitro and in vivo.•Quercetin could up-regulate the expression of IFN, STAT1, PKR, MxI, ISG15 and TLR9 in GS cells.•Quercetin exerted the indirect antiviral function by promoting the establishment of an antiviral state in host cells.