Santin inhibits influenza A virus replication through regulating MAPKs and NF-κB pathways.

Influenza A virus (IAV) causes high morbidity and significant mortality worldwide. Given the limitations of existing vaccination and antiviral drugs, it is urgent to develop new anti-influenza drugs. Flavonoids are natural polyphenolic compounds with broad applications to treatments for influenza infection. In this study, we demonstrated that santin, a flavonoid compound, showed anti-influenza activity in MDCK and THP-1 cells. Mechanistic studies revealed that santin depressed the phosphorylation of p38 MAPK, JNK/SAPK, ERK, and NF-κB factor and subsequently attenuated the expression of inflammatory cytokines in IAV-infected cells. Thus, santin is a potential candidate for the future development of anti-IAV drugs.