OBJECTIVE To investigate the therapeutic effect of Sanhan Huashi Formula (SHF) on respiratory syncytial virus (RSV)-infected mouse models and explore its potential antiviral and anti-inflammatory mechanisms using lipidomics.

METHODS Fifty-four BALB/c mice were randomly divided into six groups (n=9): blank group, model group, Ribavirin group (50 mg·kg^-1·d^-1), and SHF high (15.46 g·kg^-1·d^-1), medium (7.73 g·kg^-1·d^-1), and low-dose (3.87 g·kg^-1·d^-1) groups. A pneumonia model was established by intranasal RSV infection, followed by three consecutive days of oral gavage administration. Lung tissues were collected for histopathological evaluation using hematoxylin-eosin (HE) staining and inflammation scoring. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed to measure mRNA levels of viral gene fusion protein (F), glycoprotein (G), and inflammatory factors tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) to assess lung viral load and inflammation, while immunofluorescence staining was performed to observe the expression of RSV-F protein in lung tissues. Serum lipidomics analysis was conducted using ultra-performance liquid chromatography-quadrupole-electrostatic field orbitrap high-resolution mass spectrometry (UPLC-Q Exactive Orbitrap MS) to identify lipid metabolism changes and differential lipids.

RESULTS Compared with the blank group, mice in the model group exhibited marked pulmonary inflammatory cell infiltration and tissue injury, with significantly elevated pulmonary histopathology scores and lung index. The lung viral load and the mRNA expression levels of the inflammatory factors TNF-α and IL-6 were significantly increased, and immunofluorescence likewise indicated high expression of RSV-F protein in lung tissue. Relative to the model group, treatment with SHF at all tested doses clearly ameliorated lung tissue injury, effectively suppressed viral gene expression and inflammatory cytokine levels, and reduced the fluorescence signal intensity of RSV-F protein in the lungs. Lipidomics analysis revealed that compared with the blank group, the model group exhibited marked disturbances in lipid metabolism- characterized by dysregulation of triacylglycerol (TG), phosphatidylcholine (PC), lysophosphatidylcholine (LPC), sphingomyelin (SM), diacylglycerol (DG), lysophosphatidylethanolamine (LPE), and phosphatidylethanolamine (PE). High-dose SHF treatment reversed these RSV-induced lipid abnormalities.

CONCLUSION SHF effectively alleviates RSV-induced pulmonary inflammation and pathological injury, reduces pulmonary RSV viral load, and may exert these effects by modulating dysregulated lipid metabolism in peripheral blood.