Deciphering the core antiviral mechanism of Yinqiao powder: Inhibition of dengue virus adsorption mediated by wogonin via host receptor HSP90AA1 blockade.

OBJECTIVE

Dengue virus (DENV) remains a significant public health threat, yet no effective antiviral therapies are currently available. Based on TCM theory, the treatment of dengue emphasizes the principles of clearing heat and detoxifying, cooling blood and dissipating blood stasis. Yinqiao Powder (YQS), a famous clearing heat and detoxifying formula, has a good curative effect on the virus-induced diseases, and theoretically has potential value in the treatment of dengue.

PURPOSE: This study aims to investigate the antiviral mechanism of YQS against DENV.

METHODS

Time-of-drug-addition assay elucidated phase-specific antiviral target of YQS in dengue infection, while plaque, cytopathic effect (CPE), quantitative real-time PCR, Western blot, and immunofluorescence assays were employed to assess the antiviral efficacy of YQS. Network pharmacology analysis was performed to identify convergent molecular targets between YQS constituents and DENV pathophysiological cascades. The interactions between wogonin and HSP90AA1 were characterized using cellular thermal shift assay, drug affinity responsive target stability, molecular docking, and surface plasmon resonance. Immunofluorescence and co-immunoprecipitation assays were implemented to interrogate whether wogonin modulates E/HSP90AA1 interaction. Ultimately, the in vivo protective activity of YQS was assessed in DENV-2-infected AG129 mice.

RESULTS

YQS inhibited DENV-2 infection with an IC50 value of 468.5 μg/ml. YQS reduced progeny virus by over 75% and CPE, suppressed expression of viral RNA and proteins during the adsorption phase across multiple cell lines. The active component wogonin was identified through network pharmacology. Similarly, wogonin exhibited potent inhibition of DENV adsorption, reducing plaque formation by over 45%. Further target study demonstrated that wogonin targeted HSP90AA1 and blocked its interaction with viral E protein. In vivo findings revealed YQS mitigated weight loss, extended survival, diminished serum viral load, and conferred hepatoprotective effects in AG129 mice.

CONCLUSION

YQS potently inhibits DENV infection in vitro and in vivo. The antiviral activity of its component wogonin may contribute to this effect, potentially through binding to the host receptor HSP90AA1 and reducing DENV adsorption.