Effects of Uncaria tomentosa and Uncaria guianensis aqueous extract on enzyme activity and modulation of hemostasis

Abstract

The species Uncaria tomentosa and Uncaria guianensis are medicinal plants rich in bioactive compounds with anti-inflammatory properties. The objectives of this study were to evaluate the potential of these herbal medicines in modulating phospholipases A2 and proteases (involved in hemostasis and inflammation), using Bothrops moojeni venom as a study model. To achieve this, the plant extracts were characterized for their phenolic composition by chromatography, and the action of the extracts was evaluated through plate inhibition assays. The phospholipase activity induced by the venom of B. moojeni was significantly inhibited by both extracts, ranging from 10 to 18% and 10 to 46% for the extracts U. tomentosa and U. guianensis, respectively. The greatest inhibitory action of hemolysis was observed for the extract of U. guianensis, when incubated with B. moojeni venom, with results between 14 and 60%. In the thermal hemolysis assay, the highest doses tested exerted a greater protective effect on erythrocyte membranes. The proteolytic activity was significantly inhibited, showing results from 10 to 27% for U. tomentosa and 10 to 40% for U. guianensis. For thrombolytic activity, significant inhibition was observed only at the highest dose of U. guianensis (53%) and controls containing only the extracts showed thrombolytic action. Both extracts were able to prolong the clotting time induced by B. moojeni venom. The results demonstrate that the extracts act as modulators on phospholipases A₂ and proteases. Thus, these herbal medicines are promising alternatives in the treatment of inflammatory diseases and hemostatic disorders.