title: In vitro antiviral activity and underlying molecular mechanisms of dipotassium glycyrrhetate against porcine reproductive and respiratory syndrome virus.
abstract: BACKGROUND
  Porcine reproductive and respiratory syndrome virus (PRRSV) has caused large economic losses in the swine industry. Currently, there is no effective way to prevent PRRSV infection. In this study, we investigated the inhibitory effect of dipotassium glycyrrhetate (DG), a derivative of glycyrrhetinic acid, on PRRSV infection ability.
  
  
  METHODS
  The cytotoxicity of DG was measured by MTT assay, and the effects of DG on PRRSV N gene/protein were investigated using real-time PCR, western blot and immunofluorescence assay. In addition, the effect of DG on cell apoptosis was analysed by fluorescence staining.
  
  
  RESULTS
  Our results indicated that DG could effectively inhibit virus replication and N gene expression in MARC-145 cells infected with PRRSV. When the infected cells received DG, the numbers of apoptotic cells were decreased, and the cleaved caspase-3 contents were decreased dramatically.
  
  
  CONCLUSIONS
  Our study demonstrates that DG could effectively inhibit the PRRS virus via multiple pathways including inhibition of virus replication and N gene expression and reduction of apoptotic cells. DG can serve as a potential chemical for PRRSV prevention and control.
authors.affiliation: College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, PR China.
authors.forename: Zhi-Wei
authors.initials: ZW
authors.lastname: Wang
authors.forename: Na
authors.initials: N
authors.lastname: Sun
authors.forename: Cai-Hong
authors.initials: CH
authors.lastname: Wu
authors.forename: Jun-Bing
authors.initials: JB
authors.lastname: Jiang
authors.forename: Yuan-Sheng
authors.initials: YS
authors.lastname: Bai
authors.forename: Hong-Quan
authors.initials: HQ
authors.lastname: Li
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D000998:Antiviral Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D002460:Cell Line; D002522:Chlorocebus aethiops; D015870:Gene Expression / Q000187:drug effects; D019695:Glycyrrhizic Acid / Q000494:pharmacology*; D019590:Nucleocapsid Proteins / Q000096:biosynthesis*; D019318:Porcine Reproductive and Respiratory Syndrome / Q000188:drug therapy* / Q000517:prevention & control; D019316:Porcine respiratory and reproductive syndrome virus / Q000187:drug effects; D013552:Swine; D014779:Virus Replication / Q000187:drug effects*
chemical_list: D000893:Anti-Inflammatory Agents; D000998:Antiviral Agents; D019590:Nucleocapsid Proteins; D019695:Glycyrrhizic Acid; D053148:Caspase 3