Antiviral effect of diammonium glycyrrhizinate on cell infection by porcine parvovirus

Antiviral alternatives against important members of the subfamily Parvovirinae: a review

Parvoviruses are responsible for multiple diseases, and there is a critical need for effective antiviral therapies. Specific antiviral treatments for parvovirus infections are currently lacking, and the available options are mostly supportive and symptomatic. In recent years, significant research efforts have been directed toward understanding the molecular mechanisms of parvovirus replication and identifying potential targets for antiviral interventions. This review highlights the structure, pathogenesis, and treatment options for major viruses of the subfamily Parvovirinae, such as parvovirus B19 (B19V), canine parvovirus type 2 (CPV-2), and porcine parvovirus (PPV) and also describes different approaches in the development of antiviral alternatives against parvovirus, including drug repurposing, serendipity, and computational tools (molecular docking and artificial intelligence) in drug discovery. These advances greatly increase the likelihood of discoveries that will lead to potent antiviral strategies against different parvovirus infections.

A Review of the Antiviral Activities of Glycyrrhizic Acid, Glycyrrhetinic Acid and Glycyrrhetinic Acid Monoglucuronide

Licorice, a natural medicine derived from the roots and rhizomes of Glycyrrhiza species, possesses a wide range of therapeutic applications, including antiviral properties. Glycyrrhizic acid (GL) and glycyrrhetinic acid (GA) are the most important active ingredients in licorice. Glycyrrhetinic acid 3-O-mono-β-d-glucuronide (GAMG) is the active metabolite of GL. GL and its metabolites have a wide range of antiviral activities against viruses, such as, the hepatitis virus, herpes virus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and so on. Although their antiviral activity has been widely reported, the specific mechanism of action involving multiple links such as the virus itself, cells, and immunity are not clearly established. In this review, we will give an update on the role of GL and its metabolites as antiviral agents, and detail relevant evidence on the potential use and mechanisms of actions. Analyzing antivirals, their signaling, and the impacts of tissue and autoimmune protection may provide promising new therapeutic strategies.

Broad Antiviral Spectrum of Glycyrrhizic Acid for Human and Veterinary Medicine: Reality or Fiction?

BACKGROUND

Emerging virus infections provoke health problems in people and animals, which generate social and economic issues worldwide. This has spurred the search for new pharmacological strategies to confront them.

SUMMARY

The purpose of this review is to draw the reader's attention to pharmacological evaluations of glycyrrhizic acid (GA) and its analogs on the broad range of viruses known in human and veterinary medicine. GA is the main water-soluble constituent extracted from the roots of plants from the genus Glycyrrhiza, commonly known as licorice root. It has long been used due to its broad spectrum of bioactivities, including anti-inflammatory, antiulcer, and antitumor properties. It has also been proposed as an antiviral agent. Medicines derived from GA are currently being used to combat acute and chronic hepatitis and herpes viruses.

KEY MESSAGES

This review suggests that GA could be a new broad-spectrum antiviral due to its ability to inhibit DNA or RNA viruses both in vitro and in vivo. GA could be a potential drug for preventing and/or treating various viral diseases.

Therapeutic Options for the SARS-CoV-2 Virus: Is There a Key in Herbal Medicine?

SARS-CoV-2 has been responsible for over 500 million cumulative cases all over the world since December 2019 and has marked the third introduction of a highly pathogenic virus after SARS-CoV and MERS-CoV. This virus is in a winning situation because scientists are still racing to explore effective therapeutics, vaccines, and event treatment regimens. In view of progress in current disease management, until now none of the preventive/treatment measures can be considered entirely effective to treat SARS-CoV-2 infection. Therefore, it is required to look up substitute ways for the management of this disease. In this context, herbal medicines could be a good choice. This article emphasizes the antiviral potential of some herbal constituents which further can be a drug of choice in SARS-CoV-2 treatment. This article may be a ready reference for discovering natural lead compounds and targets in SARS-CoV-2 associated works.

Research Progress on the Antiviral Activity of Glycyrrhizin and its Derivatives in Liquorice

Liquorice is a traditional medicine. Triterpenoids such as glycyrrhizin and glycyrrhetinic acid are the main active constituents of liquorice. Studies have revealed that these compounds exert inhibitory effects on several viruses, including SARS-CoV-2. The main mechanisms of action of these compounds include inhibition of virus replication, direct inactivation of viruses, inhibition of inflammation mediated by HMGB1/TLR4, inhibition of β-chemokines, reduction in the binding of HMGB1 to DNA to weaken the activity of viruses, and inhibition of reactive oxygen species formation. We herein review the research progress on the antiviral effects of glycyrrhizin and its derivatives. In addition, we emphasise the significance of exploring unknown antiviral mechanisms, structural modifications, and drug combinations in future studies.

Ferulic Acid Protects against Porcine Parvovirus Infection-Induced Apoptosis by Suppressing the Nuclear Factor-κB Inflammasome Axis and Toll-Like Receptor 4 via Nonstructural Protein 1

Background

Porcine parvovirus (PPV) infection-induced apoptosis was recently identified as an important pathological factor in PPV-induced placental tissue damage, resulting in reproduction failure. In the present study, we demonstrate the possible involvement of toll-like receptor (TLR) 4 and nuclear factor (NF)-κB inflammasome activation in PPV infection-induced apoptosis and the protective potential of ferulic acid (FA). PPV infection significantly activated the expression levels of TLR4, NF-κB, MyD88, and interleukin (IL)-6. However, FA ameliorated the pathological process, prevented histological alterations, and inhibited the apoptosis rate in porcine kidney (PK-15) cells infected with PPV.

Results

FA inhibited PPV infection-induced inflammasome activation as shown by decreases in the expression of NF-κB, MyD88, and IL-6. FA also downregulated nonstructural (NS) 1 protein expression in infected PK-15 cells.

Conclusions

FA downregulated NS1 and TLR4 signaling, prevented the overproduction of reactive oxygen species, and suppressed the NF-κB inflammasome axis to inhibit PPV-induced apoptosis in PK-15 cells.

Antiviral effect of lithium chloride on infection of cells by porcine parvovirus

Porcine parvovirus (PPV) causes reproductive failure in pigs, which leads to economic losses to the industry. As reported previously, LiCl efficiently impairs the replication of a variety of viruses, including the coronavirus infectious bronchitis virus (IBV), transmissible gastroenteritis virus (TGEV), and pseudorabies herpesvirus. We demonstrate for the first time that inhibition of PPV replication in swine testis (ST) cells by LiCl is dose-dependent, and that the antiviral effect of LiCl occurred in the early phase of PPV replication. These results indicate that LiCl might be an effective anti-PPV drug to control PPV disease. Further studies are required to explore the mechanism of the antiviral effect of LiCl on PPV infection in vivo.