Antiviral effect of diammonium glycyrrhizinate and lithium chloride on cell infection by pseudorabies herpesvirus

Abstract

Diammonium glycyrrhizin (DG), a salt from glycyrrhizinate (GL) that is a major active component of licorice root extract with various pharmacological activities was investigated for its inhibitory effect on pseudorabies virus (PrV) infection. In parallel, lithium chloride (LiCl), a chemical reagent with potential antiviral activity was compared with DG for their inhibitory ability against PrV infection in vitro. Virus plaque-reduction assays, PCR and RT-PCR analysis indicated that both drugs inhibited cell infection by PrV. Moreover, addition of the drugs resulted in fewer apoptotic cells during PrV infection.

The effect ofHouttuynia cordatainjection on pseudorabies herpesvirus (PrV) infectionin vitro

“…At the same time, RT-PCR amplifying the gD gave rise to similar results, confirming the inhibitory effect of H. cordata. The glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was used as an internal reference for our PCR analysis, and the housekeeping gene did not vary as previously reported (Sui et al, 2010). In this study we firstly selected PrV gD gene as a target gene because it is active during cell adhesion and the interaction of gD with its cellular receptor mediates the binding of PrV infected cells to uninfected cells (Hanssens et al, 1995).…”

“…To analyze the cell proliferation, cells in 96-well plates were incubated with the drug as above. Then, conventional MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] cell viability assays were performed and the optical density (OD) of the wells was determined using a plate reader at a test wavelength of 570 nm (Sui et al, 2010). Cell survival rate was calculated as drug average OD value/control average OD value and 50% above cell survival rate was regarded as a non-toxic concentration of drug.…”

“…To analyze the impact of H. cordata on the viral genome load, the amplification of PrV gD gene, a major structural gene of PrV (approximately 1200 bp in length) was performed by PCR and reverse transcription (RT)-PCR according to Sui et al (2010). Briefly, virus-infected cells were subjected to DNA extraction with a commercial kit (Qiagen, Hilden, Germany).…”

“…Virus titration and infectivity analysis were performed according to established methods with modifications (Ren et al, 2008;Li et al, 2009;Sui et al, 2010). Briefly, cells seeded in 24-well culture plates were inoculated with serially diluted viruses at 37°C for 1 h, after which they were washed three times with PBS.…”

Antiviral effects of the constituents derived from Chinese herb medicines on infectious bursal disease virus

“…Pompei et al (2009) documented the antiviral properties of glycyrrhizic acid and its semisynthetic derivatives and led to the conclusion that new synthetic derivatives of glycyrrhizic acid are even more active than the parent molecule, and glycyrrhizic acid can alter the expression of viral genes involved in cell transformation, thus opening a new window for speculating on viral carcinogenesis. It was reported that glycyrrhizin was active against herpes viruses such as varicella zoster virus (VZV), SARS coronavirus (SARS-CoV), Epstein-Barr virus (EBV) and influenza A virus (IAV) (Baba & Shigeta, 1987;Hoever et al, 2005;Lin, 2003;Wolkerstorfer et al, 2009) and diammonium glycyrrhizin, a salt from glycyrrhizinate, possessed strong inhibitory effect on pseudorabies herpesvirus (PrV) and infectious bronchitis virus (IBV) (Li et al, 2009;Sui et al, 2010). Dipotassium glycyrrhizinate also is a salt from glycyrrhizinate and showed significant activity against IBDV in vitro in our study.…”