title: Inhibitory activity of the isoflavone biochanin A on intracellular bacteria of genus Chlamydia and initial development of a buccal formulation.
abstract: Given the established role of Chlamydia spp. as causative agents of both acute and chronic diseases, search for new antimicrobial agents against these intracellular bacteria is required to promote human health. Isoflavones are naturally occurring phytoestrogens, antioxidants and efflux pump inhibitors, but their therapeutic use is limited by poor water-solubility and intense first-pass metabolism. Here, we report on effects of isoflavones against C. pneumoniae and C. trachomatis and describe buccal permeability and initial formulation development for biochanin A. Biochanin A was the most potent Chlamydia growth inhibitor among the studied isoflavones, with an IC50 = 12 µM on C. pneumoniae inclusion counts and 6.5 µM on infectious progeny production, both determined by immunofluorescent staining of infected epithelial cell cultures. Encouraged by the permeation of biochanin A across porcine buccal mucosa without detectable metabolism, oromucosal film formulations were designed and prepared by a solvent casting method. The film formulations showed improved dissolution rate of biochanin A compared to powder or a physical mixture, presumably due to the solubilizing effect of hydrophilic additives and presence of biochanin A in amorphous state. In summary, biochanin A is a potent inhibitor of Chlamydia spp., and the in vitro dissolution results support the use of a buccal formulation to potentially improve its bioavailability in antichlamydial or other pharmaceutical applications.
authors.affiliation: Division of Pharmaceutical Biosciences, CDR, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland.
authors.forename: Leena
authors.initials: L
authors.lastname: Hanski
authors.affiliation: Pharmaceutical Sciences Laboratory, Department of Biosciences, Abo Akademi University, Turku, Finland.
authors.forename: Natalja
authors.initials: N
authors.lastname: Genina
authors.affiliation: Laboratories for Chemical Biology, Umeå University, Umeå, Sweden.
authors.forename: Hanna
authors.initials: H
authors.lastname: Uvell
authors.affiliation: Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland.
authors.forename: Kristina
authors.initials: K
authors.lastname: Malinovskaja
authors.affiliation: Department of Clinical Microbiology, Umeå University, Umeå, Sweden; Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden; Laboratory for Molecular Infection Medicine, Umeå University, Umeå, Sweden.
authors.forename: Åsa
authors.initials: Å
authors.lastname: Gylfe
authors.affiliation: Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland.
authors.forename: Timo
authors.initials: T
authors.lastname: Laaksonen
authors.affiliation: Pharmaceutical Sciences Laboratory, Department of Biosciences, Abo Akademi University, Turku, Finland.
authors.forename: Ruzica
authors.initials: R
authors.lastname: Kolakovic
authors.affiliation: Laboratory of Industrial Physics, Department of Physics and Astronomy, University of Turku, Turku, Finland.
authors.forename: Ermei
authors.initials: E
authors.lastname: Mäkilä
authors.affiliation: Laboratory of Industrial Physics, Department of Physics and Astronomy, University of Turku, Turku, Finland.
authors.forename: Jarno
authors.initials: J
authors.lastname: Salonen
authors.affiliation: Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland.
authors.forename: Jouni
authors.initials: J
authors.lastname: Hirvonen
authors.affiliation: Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden; Laboratory for Molecular Infection Medicine, Umeå University, Umeå, Sweden; Department of Chemistry, Umeå University, Umeå, Sweden.
authors.forename: Mikael
authors.initials: M
authors.lastname: Elofsson
authors.affiliation: Pharmaceutical Sciences Laboratory, Department of Biosciences, Abo Akademi University, Turku, Finland.
authors.forename: Niklas
authors.initials: N
authors.lastname: Sandler
authors.affiliation: Division of Pharmaceutical Biosciences, CDR, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland.
authors.forename: Pia M
authors.initials: PM
authors.lastname: Vuorela
mesh_terms: D000278:Administration, Buccal; D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D002478:Cells, Cultured; D002690:Chlamydia Infections / Q000188:drug therapy*; D002692:Chlamydia trachomatis / Q000187:drug effects / Q000254:growth & development*; D016993:Chlamydophila pneumoniae / Q000187:drug effects / Q000254:growth & development*; D019833:Genistein / Q000627:therapeutic use*; D006801:Humans; D007529:Isoflavones / Q000627:therapeutic use; D008826:Microbial Sensitivity Tests; D065568:Oral Mucosal Absorption / Q000502:physiology*; D010936:Plant Extracts / Q000627:therapeutic use; D013552:Swine
chemical_list: D000900:Anti-Bacterial Agents; D007529:Isoflavones; D010936:Plant Extracts; D019833:Genistein; C004541:biochanin A