Qianjinweijingtang Decoction and Its Granule Inhibit Respiratory Syncytial Virus Infection and the Associated Inflammatory Response.

Respiratory syncytial virus infection (RSV) represents a leading cause behind acute lower respiratory infections affecting both children and older adults. Qianjinweijingtang (QJWJT), a classical Chinese herbal formula widely used for respiratory diseases, was investigated in this study to compare the anti-RSV efficacy and chemical profiles of its traditional decoction and granule formulation, and to elucidate the underlying mechanisms. Both formulations significantly inhibited RSV infection and its induced inflammatory responses in vitro and in vivo. Further mechanistic analysis revealed that QJWJT acted at an early step of the RSV replication cycle, most likely by interfering with viral entry. UHPLC-Q-Orbitrap HRMS analysis revealed that QJWJT was mainly composed of fatty acids, flavonoids, and phenolic acids, with isoliquiritigenin, quercetin, and gallic acid identified as key bioactive constituents. Moreover, all three compounds bound favorably to both the respiratory syncytial virus fusion (RSV-F) and glycoprotein (RSV-G). Network pharmacology combined with western blotting analysis indicated that QJWJT could inhibit RSV infection by downregulating Hypoxia-Inducible Factor 1-alpha (HIF-1α) expression. In conclusion, this study suggests that the granule formulation has the potential to serve as another option for the traditional decoction, providing a reference for the modernization of Chinese herbal formulas.