title: Aurantiamide acetate from baphicacanthus cusia root exhibits anti-inflammatory and anti-viral effects via inhibition of the NF-κB signaling pathway in Influenza A virus-infected cells.
abstract: BACKGROUND
  Baphicacanthus cusia root also names "Nan Ban Lan Gen" has been traditionally used to prevent and treat influenza A virus infections. Here, we identified a peptide derivative, aurantiamide acetate (compound E17), as an active compound in extracts of B. cusia root. Although studies have shown that aurantiamide acetate possesses antioxidant and anti-inflammatory properties, the effects and mechanism by which it functions as an anti-viral or as an anti-inflammatory during influenza virus infection are poorly defined. Here we investigated the anti-viral activity and possible mechanism of compound E17 against influenza virus infection.
  
  
  METHODS
  The anti-viral activity of compound E17 against Influenza A virus (IAV) was determined using the cytopathic effect (CPE) inhibition assay. Viruses were titrated on Madin-Darby canine kidney (MDCK) cells by plaque assays. Ribonucleoprotein (RNP) luciferase reporter assay was further conducted to investigate the effect of compound E17 on the activity of the viral polymerase complex. HEK293T cells with a stably transfected NF-κB luciferase reporter plasmid were employed to examine the activity of compound E17 on NF-κB activation. Activation of the host signaling pathway induced by IAV infection in the absence or presence of compound E17 was assessed by western blotting. The effect of compound E17 on IAV-induced expression of pro-inflammatory cytokines was measured by real-time quantitative PCR and Luminex assays.
  
  
  RESULTS
  Compound E17 exerted an inhibitory effect on IAV replication in MDCK cells but had no effect on avian IAV and influenza B virus. Treatment with compound E17 resulted in a reduction of RNP activity and virus titers. Compound E17 treatment inhibited the transcriptional activity of NF-κB in a NF-κB luciferase reporter stable HEK293 cell after stimulation with TNF-α. Furthermore, compound E17 blocked the activation of the NF-κB signaling pathway and decreased mRNA expression levels of pro-inflammatory genes in infected cells. Compound E17 also suppressed the production of IL-6, TNF-α, IL-8, IP-10 and RANTES from IAV-infected lung epithelial (A549) cells.
  
  
  CONCLUSIONS
  These results indicate that compound E17 isolated from B. cusia root has potent anti-viral and anti-inflammatory effects on IAV-infected cells via inhibition of the NF-κB pathway. Therefore, compound E17 could be a potential therapeutic agent for the treatment of influenza.
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau 999078, China.
authors.forename: Beixian
authors.initials: B
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau 999078, China; State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Disease, National Clinical Centre of Respiratory Disease, The First Affiliated Hospital, Guangzhou Medical University, 151 Yanjiang Xi Road, Guangzhou 510120, China.
authors.forename: Zifeng
authors.initials: Z
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau 999078, China.
authors.forename: Qitong
authors.initials: Q
authors.lastname: Feng
authors.affiliation: State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Disease, National Clinical Centre of Respiratory Disease, The First Affiliated Hospital, Guangzhou Medical University, 151 Yanjiang Xi Road, Guangzhou 510120, China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Liang
authors.affiliation: State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Disease, National Clinical Centre of Respiratory Disease, The First Affiliated Hospital, Guangzhou Medical University, 151 Yanjiang Xi Road, Guangzhou 510120, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Infectious Diseases, Division of Virology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Zanin
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau 999078, China. Electronic address: zhjiang@must.edu.mo.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau 999078, China; State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Disease, National Clinical Centre of Respiratory Disease, The First Affiliated Hospital, Guangzhou Medical University, 151 Yanjiang Xi Road, Guangzhou 510120, China. Electronic address: nanshan@vip.163.com.
authors.forename: Nanshan
authors.initials: N
authors.lastname: Zhong
mesh_terms: D000072283:A549 Cells; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000302:isolation & purification / Q000494:pharmacology*; D000998:Antiviral Agents / Q000302:isolation & purification / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D004151:Dipeptides / Q000302:isolation & purification / Q000494:pharmacology*; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D004365:Drugs, Chinese Herbal / Q000302:isolation & purification / Q000494:pharmacology*; D057809:HEK293 Cells; D006801:Humans; D009980:Influenza A virus / Q000187:drug effects* / Q000502:physiology; D061985:Madin Darby Canine Kidney Cells; D016328:NF-kappa B / Q000037:antagonists & inhibitors* / Q000378:metabolism; D018517:Plant Roots; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology
chemical_list: D000893:Anti-Inflammatory Agents; D000998:Antiviral Agents; D004151:Dipeptides; D004365:Drugs, Chinese Herbal; D016328:NF-kappa B; C011670:N-benzoylphenylalanylphenylalinol acetate
keywords: Anti-inflammatory; Anti-viral; Aurantiamide acetate (PubChem CID:9832120); Baphicacanthus cusia root; Influenza A virus