Protective activity of the Uncaria tomentosa extracts on human erythrocytes in oxidative stress induced by 2,4-dichlorophenol (2,4-DCP) and catechol

Influence of U. tomentosa (250μg/ml) on oxidation of 2′,7′-dichlorodihydrofluoresceine diacetate in human erythrocytes induced by 2,4-DCP (250μg/ml) and catechol (100μg/ml) for 1h of incubation. [Display omitted] ► The extracts from Uncaria tomentosa leaves and bark were not toxic to human erythrocytes. ► U. tomentosa extracts reveal protective activity against 2,4-dichlorophenol toxicity. ► No protective function of extracts in human erythrocytes incubated with catechol was observed. ► Ethanolic extracts revealed more pronounced ability to inhibit oxidation in human erythrocytes. The purpose of this study was to evaluate the effect of the ethanolic and aqueous extracts of Uncaria tomentosa on human erythrocytes and additionally the assessment of protective effect of these extracts on hemolysis induction, hemoglobin oxidation, and changes in the level of reactive oxygen species (ROS) and lipid peroxidation, which were provoked by selected xenobiotics, i.e. 2,4-dichlorophenol (2,4-DCP) and catechol. All tested extracts, even at a very high concentration of 500μg/ml were not toxic to the erythrocytes because they did not cause lipid peroxidation, increase methemoglobin and ROS levels nor provoked hemolysis. The results of this study also revealed protective effect of extracts of U. tomentosa. The extracts studied depleted the extent of hemoglobin oxidation and lipid peroxidation as well as decreased the level of ROS and hemolysis, which was provoked by 2,4-DCP. No protective activity of the extracts against catechol action, which is a precursor of semiquinones in cell was found. A difference in the effect of the extracts studied was observed. Ethanol-based extracts revealed more pronounced ability to inhibit oxidation processes in human erythrocytes.