Objective: Our earlier study demonstrated an inhibition of experimental thrombogenesis after acute administration of rosemary and common thyme. The present study aimed to investigate the effect of long-term intake of these herbs on platelets, thrombus formation and bleeding time.
Methods: Western-style high-fat diet containing 5% or 0.5% dried rosemary or common thyme was given to male 6 week old C57BL/6 mice for 12 weeks. Shear-induced platelet reactivity was measured in vitro by haemostatometry. The antithrombotic effect was assessed by the laser-induced thrombosis technique in the carotid artery of mice. Bleeding time was tested by the tail cut method. Endothelial function was assessed by the flow-mediated vasodilation test.
Results: Rosemary (5% and 0.5%) significantly inhibited arterial thrombus formation. Only the higher concentration of common thyme (5%) had a significant antithrombotic effect. In 5% concentration, both rosemary and common thyme significantly inhibited platelet reactivity and enhanced the flow-mediated vasodilation.
Conclusions: Long-term daily intake of rosemary and common thyme has an antithrombotic effect, which is probably due to inhibition of platelets and stimulation of endothelial cells. The antithrombotic effect was not accompanied by prolongation of bleeding time.