Ševčovičová A, Šemeláková M, Plšíková J, Loderer D, Imreová P, Gálová E, Kožurková M, Miadoková E, Fedoročko P
Department of Genetics, Faculty of Natural Sciences, Comenius University, Mlynská dolina, 842 15 Bratislava, Slovakia.
Institute of Biology and Ecology, Faculty of Sciences, P.J. Šafárik University in Košice, Moyzesova 11, 040 01 Košice, Slovakia.
Toxicol In Vitro. 2015 Apr;29(3):631-7. doi: 10.1016/j.tiv.2015.01.016. Epub 2015 Feb 9.
The aim of this study was to explain the molecular mechanisms of action of hyperforin, a phluoroglucinol derivative found in Hypericum perforatum L. and its more stable derivative aristoforin. DNA-topology assay revealed partial DNA-protective activities of hyperforin and aristoforin against Fe(2+)-induced DNA breaks. In order to assess molecular mechanisms underlying DNA-protective activity, the potential antioxidant activity of hyperforin and aristoforin was investigated using DPPH and OH scavenging assays, reducing power assay and Fe(2+)-chelating assay. We also studied interaction of hyperforin and aristoforin with DNA using established protocols for fluorescence titration. The ability of the studied compounds to relax topoisomerase I with electrophoretic techniques was investigated. The reduction in the fluorescence of hyperforin indicated an interaction between hyperforin and DNA with a binding constant of 0.2×10(8)M(-1). We suggest that a mechanism of hyperforin/aristoforin DNA-protective abilities is based on free radicals (mainly OH) scavenging activity.
本研究的目的是解释贯叶连翘中发现的间苯三酚衍生物金丝桃素及其更稳定的衍生物伪金丝桃素的分子作用机制。DNA拓扑分析显示金丝桃素和伪金丝桃素对Fe(2+)诱导的DNA断裂具有部分DNA保护活性。为了评估DNA保护活性的分子机制，使用DPPH和OH清除试验、还原能力试验和Fe(2+)螯合试验研究了金丝桃素和伪金丝桃素的潜在抗氧化活性。我们还使用既定的荧光滴定方案研究了金丝桃素和伪金丝桃素与DNA的相互作用。研究了所研究化合物用电泳技术使拓扑异构酶I松弛的能力。金丝桃素荧光的降低表明金丝桃素与DNA之间存在相互作用，结合常数为0.2×10(8)M(-1)。我们认为金丝桃素/伪金丝桃素DNA保护能力的机制基于自由基（主要是OH）清除活性。
