Antiviral Effect of Lithium Chloride and Diammonium Glycyrrhizinate on Porcine Deltacoronavirus In Vitro

Zhai, Xiaofeng; Wang, Shilei; Zhu, Mengyan; He, Wei; Pan, Zhongzhou; Su, Shuo

The viral replication cycle includes attachment, entry, transcription, replication, gene expression, assembly, maturation, and release. We found that DG can inhibit the attachment of the virus to the cell surface, which is consistent with the results of a recent report showing that glycyrrhizin achieved a dose-dependent inhibition of the replication of HIV-1 in MOLT-4 cells, and could interfere with virus-cell binding [37] . However, the specific mechanism needs further investigation. Future experiments will determine if DG can be used not only as a treatment but also for preventing PDCoV infection. Because DG has a good water solubility, it can be used as aerosol disinfectant in piggeries to prevent the outbreak of porcine epidemic diarrhea. According to the antiviral effect, the antiviral activity of LiCl is better than that of DG, and the toxicity of DG is less than that of LiCl. We investigated the effect of LiCl combined with DG on the replication of PDCoV in LLC-PK1 cells. There were no significant differences between LiCl-treated cells and cells treated with LiCl and DG in the mean relative viral mRNA levels, indicating that there is no synergy in the inhibition of viral replication when both drugs are used in combination (data not shown).