Evaluation of the antioxidant activity of several naturally occurring coumarins and their synthesized analogues by "ferric reducing antioxidant power" assay.

Coumarins have attracted intense interest in recent years because of their diverse pharmacological properties. According to our continuing investigations of biological effects of several coumarins, the structure-antioxidant activity relationships (SARs) of six naturally occurring coumarins and their 16 synthesized analogues were established. For this purpose, the very reliable colorimetric assay (ferric reducing antioxidant power) modified to be used in 96-well microplates was used.

In vitro platelet antiaggregatory properties of 4-methylcoumarins.

Platelets play a crucial role in physiological haemostasis. However, in coronary arteries damaged by atherosclerosis, enhanced platelet aggregation, with subsequent thrombus formation, is a precipitating factor in acute myocardial infarction. Current therapeutic approaches are able to reduce approximately one quarter of cardiovascular events, but they are associated with an increased risk of bleeding and in some resistant patients are not efficient.

In vitro interactions of coumarins with iron.

Coumarins are a large group of natural substances with diverse pharmacological properties that may predetermine some of them for the prevention and/or treatment of cardiovascular diseases and also other pathologies. Free iron participates in the production of reactive oxygen species (ROS) and plays an important role in the pathogenesis of cardiovascular diseases. Therefore, chelation of iron may attenuate some ROS consequences, but on the other hand, reduction of ferric ions to ferrous ones is unfavourable and leads to intensification of ROS production.

Evaluation of natural substances from Evolvulus alsinoides L. with the purpose of determining their antioxidant potency.

In recent years, great attention has been given to the search for natural compounds or extracts with the purpose of medical use. Evolvulus alsinoides L. (Convolvulaceae) is a plant used in traditional medicine of East Asia in many indications and has known nootropic and anti-inflammatory activity.

Changes in phosphorylation of histone H2A.X and p53 in response of peripheral blood lymphocytes to gamma irradiation.

The main aim of this study was to compare the reaction of quiescent and proliferating, i.e. phytohemagglutinin (PHA)-stimulated, human peripheral blood mononuclear cells (PBMCs) to gamma-radiation, and analyse changes of proteins related to repair of DNA damage and apoptosis, such as gammaH2A.