Comparative analysis of the effect of glycyrrhizin diammonium and lithium chloride on infectious bronchitis virus infectionin vitro

Abstract

The effects of glycyrrhizin diammonium (GD) and lithium chloride (LiCl) on cell infection by avian infectious bronchitis virus (IBV) were investigated using cytopathic effect observation, plaque-reduction assay and reverse transcriptase-polymerase chain reaction. The anti-viral effect of GD and LiCl on virus, on virus-infected cells or on cells pre-treated by both drugs was analysed, respectively. Our results showed that GD had a direct antiviral activity, leading to complete inhibition of cell infection. The cell infection was not alleviated by either pre-treatment of cells with GD or addition of the drug post infection, confirming that the inhibitory effect of GD, unlike LiCl, on IBV is a viral factor, rather than a cellular factor. The inhibitory effect of both drugs was confirmed by infecting primary chicken embryo kidney cells. In addition, apoptosis of infected cells was positively related with cytopathic effect and could be inhibited by effective drug treatment. Our data indicate that GD and LiCl have potential to prevent IBV infection in vitro through different antiviral mechanisms. The data are helpful for using antivirals efficiently.

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

“…It was also found that the anti-IAV effect of glycyrrhizin was not only limited to an early step in the virus replication cycle, but was also mediated by an interaction with the cell membrane which most likely resulted in reduced endocytotic activity and hence reduced virus uptake (Wolkerstorfer et al, 2009). However, Li et al (2009) confirmed that glycyrrhizin diammonium had a direct anti-IBV activity and the inhibitory effect was a viral factor, rather than a cellular factor.…”

“…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.…”

Sambucus nigra Extracts Inhibit Infectious Bronchitis Virus at an Early Point during Replication

“…These human coronaviruses (HCoV) include ones that may cause up to 20% of the common cold (HCoV 229E, HCoV OC43); HCoV NL63 and HCoV HKU1, which cause mild to severe respiratory diseases; the SARS CoV, which emerged in 2003 with a 10% mortality rate; and the recently emerged MERS CoV, which currently has a 57% case fatality rate [81,82]. Some evidence supports this idea, in that glycyrrhizin, the active chemical from G. radix extracts, inhibited not only IBV, but also the SARS CoV [25,83].…”

“…The range of plants that have been surveyed for their potential as anti-IBV agents is also limited, although, purified compounds isolated from Glycyrrhiza radix (licorice root) [25] and Forsythia suspensa (weeping forsythia) [26] have shown effectiveness against IBV in vitro. However, the use of these extracts or the active ingredients from these extracts for long-term treatment or prevention strategies poses some toxicity concerns [27][28][29].…”

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

“…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.…”