title: Computer-guided approach to access the anti-influenza activity of licorice constituents.
abstract: Neuraminidase (NA), a key enzyme in viral replication, is the first-line drug target to combat influenza. On the basis of a shape-focused virtual screening, the roots of Glycyrrhiza glabra (licorice) were identified as plant species with an accumulation of constituents that show 3D similarities to known influenza NA inhibitors (NAIs). Phytochemical investigation revealed 12 constituents identified as (E)-1-[2,4-dihydroxy-3-(3-methyl-2-butenyl)phenyl]-3-(8-hydroxy-2,2-dimethyl-2H-1-benzopyran-6-yl)-2-propen-1-one (1), 3,4-dihydro-8,8-dimethyl-2H,8H-benzo[1,2-b:3,4-b']dipyran-3-ol (2), biochanin B (3), glabrol (4), glabrone (5), hispaglabridin B (6), licoflavone B (7), licorice glycoside B (8), licorice glycoside E (9), liquiritigenin (10), liquiritin (11), and prunin (12). Eleven of these constituents showed significant influenza virus NA inhibition in a chemiluminescence (CL)-based assay. Additional tests, including (i) a cell-based cytopathic effect inhibition assay (general antiviral activity), (ii) the evaluation of cytotoxicity, (iii) the inhibition of the NA of Clostridium perfringens (CL- and fluorescence (FL)-based assay), and (iv) the determination of self-fluorescence and quenching, provided further perspective on their anti-influenza virus potential, revealing possible assay interference problems and false-positive results. Compounds 1, 3, 5, and 6 showed antiviral activity, most likely caused by the inhibition of NA. Of these, compounds 1, 3, and 6 were highly ranked in shape-focused virtual screening.
authors: Institute of Pharmacy/Pharmacognosy, Center for Molecular Biosciences Innsbruck, University of Innsbruck , Innrain 80-82, 6020 Innsbruck, Austria.
authors: Ulrike
authors: U
authors: Grienke
authors: Heike
authors: H
authors: Braun
authors: Nora
authors: N
authors: Seidel
authors: Johannes
authors: J
authors: Kirchmair
authors: Martina
authors: M
authors: Richter
authors: Andi
authors: A
authors: Krumbholz
authors: Susanne
authors: S
authors: von Grafenstein
authors: Klaus R
authors: KR
authors: Liedl
authors: Michaela
authors: M
authors: Schmidtke
authors: Judith M
authors: JM
authors: Rollinger
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000737:chemistry / Q000494:pharmacology; D001317:Austria; D017076:Computer-Aided Design; D004285:Dogs; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology; D005419:Flavonoids / Q000737:chemistry / Q000494:pharmacology; D006035:Glycyrrhiza / Q000737:chemistry*; D006801:Humans; D009980:Influenza A virus / Q000187:drug effects; D007251:Influenza, Human / Q000188:drug therapy*; D061985:Madin Darby Canine Kidney Cells; D015394:Molecular Structure; D009439:Neuraminidase / Q000187:drug effects / Q000378:metabolism*; D018517:Plant Roots / Q000737:chemistry; D014779:Virus Replication / Q000187:drug effects
chemical_list: D000998:Antiviral Agents; D004791:Enzyme Inhibitors; D005419:Flavonoids; C420863:glabrol; D009439:Neuraminidase