Beixian Zhou1, Zifeng Yang2, Qitong Feng1, Xiaoli Liang3, Jing Li3, Mark Zanin4, Zhihong Jiang5, Nanshan Zhong6. 1. 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. 2. 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. 3. 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. 4. Department of Infectious Diseases, Division of Virology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA. 5. 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. 6. 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.
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE: 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. MATERIALS AND 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.
ETHNOPHARMACOLOGICAL RELEVANCE: 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. MATERIALS AND 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: Kweku S Enninful; Samuel K Kwofie; Mark Tetteh-Tsifoanya; Amanda N L Lamptey; Georgina Djameh; Samuel Nyarko; Anita Ghansah; Michael D Wilson Journal: Front Cell Infect Microbiol Date: 2022-05-25 Impact factor: 6.073