Antiviral effect of baicalein on Porcine Deltacoronavirus infection by regulating the inflammatory responses through PI3K-Akt-NF-κB signaling pathway in cultured cells.

Porcine deltacoronavirus (PDCoV) is an newly emerged enteropathogenic coronavirus, mainly causing diarrhea in suckling piglets, and also has the potential for cross-species transmission. However, there are no effective vaccines or specific therapeutic agents for PDCoV. This study investigates the antiviral properties of baicalein against PDCoV infection in swine testicle cells (ST). It reveals that baicalein exerts a dose-dependent inhibitory effect on PDCoV replication, primarily targeting the replication stage of the viral infection by impeding viral RNA and protein synthesis. Furthermore, treatment with baicalein leads to reduced phosphorylation of PI3K, AKT, and NF-κB p65 proteins, along with decreased mRNA levels of pro-inflammatory cytokines (IL-1β, IL-6, IL-8, and TNF-α). These results signify that PDCoV replication is inhibited through the inhibition of the PI3K-Akt-NF-κB protein signaling pathway, thereby suppressing the inflammatory response. In conclusion, it underscores the potential of baicalein as a therapeutic candidate for treating PDCoV infection.