The optimal decoction time of Yinqiao Powder on inhibit influenza A virus FM1 in mice

Abstract

Background: Yinqiao Powder (YQP) is administered in Traditional Chinese Medicine (TCM) for febrile infectious diseases and has been demonstrated to fight the prevalence of influenza. Objective: The present study aimed to identify the optimal decoction time of YQP on inhibit influenza A virus FM1 and investigate the molecular mechanisms of different decocting time YQP. Methods: The male BALB/c mice were made into pneumonia model of influenza A virus FM1. They were randomly assigned to twelve groups: blank control group, model control group, tamiflu (27.5 mg/Kg) group, 3 minutes YQP (High-dose group 30 g/Kg·d, Middle-dose group 15 g/Kg·d, and Low-dose group 7.5 g/Kg·d) groups, 6 minutes YQP (High-dose group 30 g/Kg·d, Middle-dose group 15 g/Kg·d, and Low-dose group 7.5 g/Kg·d) groups, and 12 minutes YQP (High-dose group 30 g/Kg·d, Middle-dose group 15 g/Kg·d, and Low-dose group 7.5 g/Kg·d) groups. All groups were administrated for 7 days. The mice were killed after the third and last days. Viral load of lung tissues were observed by Real-time PCR. Pulmonary index and inhibition rate were calculated by formula. Furthermore, the mice macrophage Ana-1 was infected by FM1, treated with different decocting time YQP drug-containing serum for 24 h. TLR3/4, MyD88, TRAF-6, TRAM and TRIF mRNA were detected by Real-time PCR. TLR3/4 proteins were observed by western blot. Results: All YQP intervention groups induced a reduction in the viral load and pulmonary index on the third and last days of infection, especially in 3 minutes YQP H/M/L groups and 6 minutes High-dose group. Meanwhile, YQP intervention groups led to significant decrease in TLR3/4, MyD88, TRAF-6, TRAM and TRIF mRNA levels and TLR3/4 proteins, in particular with 3 and 6 minutes YQP groups. Conclusion: YQP could protect the lung tissue and alleviate the inflammation caused by influenza A virus FM1. The optimal decoction time of YQP was 3to 6minutes on inhibit influenza A virus FM1 in mice.