Lichen secondary metabolites as DNA-interacting agents

• Published in: Toxicology in vitro 2014-03, Vol.28 (2), p.182-186
• Main Authors: Plsíkova, J., Stepankova, J., Kasparkova, J., Brabec, V., Backor, M., Kozurkova, M.
• Format: Article
• Language: English
• Subjects: Animals; Benzoates - pharmacology; Benzofurans - pharmacology; Cattle; Circular Dichroism; DNA - drug effects; DNA - metabolism; DNA-binding; Emodin - analogs & derivatives; Emodin - pharmacology; Humans; Hydroxybenzoates - pharmacology; Intercalating Agents - pharmacology; Kinetics; Lichens; Lichens - chemistry; Lichens - metabolism; Nucleic Acid Conformation; Spectrophotometry, Ultraviolet; Topoisomerase I Inhibitors - pharmacology; Topoisomerase I, II; Topoisomerase II Inhibitors - pharmacology
• ISSN: 0887-2333; 1879-3177
• DOI: 10.1016/j.tiv.2013.11.003

•Interactions of selected lichen secondary metabolites 1–4 with calf thymus DNA were studied.•Binding constants of 4.3×105–2.4×107M−1 were determined from titration.•Among all studied compounds, only gyrophoric acid was shown to inhibit Topo I. A series of lichen secondary metabolites (parietin, atranorin, usnic and gyrophoric acid) and their interactions with calf thymus DNA were investigated using molecular biophysics and biochemical methods. The binding constants K were estimated to range from 4.3×105 to 2.4×107M−1 and the percentage of hypochromism was found to be 16–34% (from spectral titration). The results of spectral measurement indicate that the compounds act as effective DNA-interacting agents. Electrophoretic separation studies prove that from all the metabolites tested in this study, only gyrophoric acid exhibited an inhibitory effect on Topo I (25μM).