The Chinese medicine monomer Schisandrin C inhibits PRRSV infection by regulating the OGT-PI3K/AKT/mTOR signaling pathway

Porcine Reproductive and Respiratory Syndrome (PRRS) is a major infectious disease in the global swine industry, caused by the Porcine Reproductive and Respiratory Syndrome Virus (PRRSV). The virus leads to reproductive disorders in sows and reduced semen quality in boars, resulting in significant economic losses. Although commercial vaccines are available, they remain insufficient for comprehensive control of different viral strains, making the development of new Antiviral approaches crucial. Traditional Chinese Medicine (TCM), with its long history and extensive medicinal experience, represents a vital resource for novel drug discovery. By integrating modern scientific techniques, the small-molecule compounds inherent in TCM are increasingly recognized as promising Antiviral agents with substantial research potential. This study systematically screened 300 monomeric compounds from traditional Chinese medicines, ultimately identifying Schisandrin C (SC) as a potential candidate drug against PRRSV. SC is an active component of Schisandra, which has Antiviral and liver-protective effects. In this study, we found that SC effectively inhibits the proliferation of PRRSV at micromolar concentrations while exhibiting broad-spectrum inhibitory activity against multiple clinically isolated PRRSV strains. Further mechanistic studies showed that SC inhibits PRRSV by promoting O-GlcNAc transferase (OGT) expression, which suppresses the PI3K/Akt/mTOR pathway. These findings suggest that SC holds promise as a candidate drug for combating PRRSV.