title: Ficus religiosa L. bark extracts inhibit human rhinovirus and respiratory syncytial virus infection in vitro.
abstract: BACKGROUND
  Ficus religiosa L. is one of the most relevant members of the family of Moraceae. It is the most sacred tree of South Asia, and it is used in traditional Ayurvedic and Unani medicine to cure respiratory disorders like cough, wheezing and asthma. Some studies were performed to investigate the anti-asthmatic potential of F. religiosa bark, leaves and fruit extracts but none of them tested their antiviral activity against viruses responsible for the exacerbation of wheezing and asthma.
  
  
  OBJECTIVE
  The present study was undertaken to investigate the antiviral activity of F. religiosa L. extracts against respiratory viruses such as human respiratory syncytial virus (RSV) and human rhinovirus (HRV).
  
  
  METHODS
  The antiviral activity of F. religiosa L. was tested in vitro by plaque reduction and virus yield assays and the major mechanism of action was investigated by virus inactivation and time-of-addition assays.
  
  
  RESULTS
  F. religiosa L. methanol bark extract was the most active against HRV with an EC50 of 5.52 µg/mL. This extract likely inhibited late steps of replicative cycle. Water bark extract was the most active against RSV with an EC50 between 2.23 and 4.37 µg/mL. Partial virus inactivation and interference with virus attachment were both found to contribute to the anti-RSV activity. Replication of both viruses was inhibited in viral yield reduction assays.
  
  
  CONCLUSIONS
  The results of the present study demonstrate that F. religiosa L. is endowed with antiviral activity against RSV and HRV in vitro. Further work remains to be done to identify the active components and to assess the therapeutic potential in vivo.
authors.affiliation: Department of Clinical and Biological Sciences, University of Torino, 10043 Orbassano, Torino, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Cagno
authors.affiliation: Department of Clinical and Biological Sciences, University of Torino, 10043 Orbassano, Torino, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Civra
authors.affiliation: Department of Pharmaceutical Sciences & Technology, Birla Institute of Technology, Mesra, Ranchi 83215, India.
authors.forename: Ravi
authors.initials: R
authors.lastname: Kumar
authors.affiliation: Department of Pharmaceutical Sciences & Technology, Birla Institute of Technology, Mesra, Ranchi 83215, India.
authors.forename: Subhankar
authors.initials: S
authors.lastname: Pradhan
authors.affiliation: Department of Clinical and Biological Sciences, University of Torino, 10043 Orbassano, Torino, Italy.
authors.forename: Manuela
authors.initials: M
authors.lastname: Donalisio
authors.affiliation: Department of Pharmaceutical Sciences & Technology, Birla Institute of Technology, Mesra, Ranchi 83215, India.
authors.forename: Barij Nayan
authors.initials: BN
authors.lastname: Sinha
authors.affiliation: Department of Pharmaceutical Sciences & Technology, Birla Institute of Technology, Mesra, Ranchi 83215, India. Electronic address: manik@bitmesra.ac.in.
authors.forename: Manik
authors.initials: M
authors.lastname: Ghosh
authors.affiliation: Department of Clinical and Biological Sciences, University of Torino, 10043 Orbassano, Torino, Italy. Electronic address: david.lembo@unito.it.
authors.forename: David
authors.initials: D
authors.lastname: Lembo
mesh_terms: D000998:Antiviral Agents / Q000494:pharmacology*; D045744:Cell Line, Tumor; D030681:Ficus; D006801:Humans; D010850:Picornaviridae Infections / Q000188:drug therapy; D024301:Plant Bark; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves; D018357:Respiratory Syncytial Virus Infections / Q000188:drug therapy; D018113:Respiratory Syncytial Virus, Human / Q000187:drug effects* / Q000502:physiology; D012229:Rhinovirus / Q000187:drug effects* / Q000502:physiology; D053585:Virus Attachment / Q000187:drug effects; D038301:Virus Inactivation / Q000187:drug effects; D053586:Virus Internalization / Q000187:drug effects
chemical_list: D000998:Antiviral Agents; D010936:Plant Extracts
keywords: Antiviral activity; Asthma; Ayurveda; Ficus religiosa; Respiratory syncytial virus; Rhinovirus