Antithrombotic effects and related mechanisms of Salvia deserta Schang root EtOAc extracts

Salvia deserta Schang (SDS) belongs to the same family as Salvia miltiorrhiza bunge, one of the antithrombotic Chinese herbal medicines. In our study, EtOAc root extracts were analyzed for their effects on adenosine diphosphate (ADP)-induced platelet aggregation in rabbits and FeCl₃-induced rat common carotid artery thrombosis as well as on rat blood plasma concentrations of thromboxane B2 (TXB₂), 6-keto-prostaglandin F1 alpha (6-keto-PGF_1α), antithrombin-III (AT-III), protein C (PC), plasminogen (PLG), plasminogen activator inhibitor (PAI-1), von Willebrand factor (vWF) and tissue-type plasminogen activator (t-PA). EtOAc extracts from SDS roots had significant inhibitory effects on ADP-induced maximum platelet aggregation rate (10.2 ± 2.6 vs control 35.7 ± 5.2; P < 0.05), reduced the FeCl₃-induced rat common carotid artery thrombus weight and thrombus area ratio (P < 0.05), significantly decreased plasma TXB₂, vWF and PAI-1 levels and increased 6-keto-PGF_1α and t-PA levels in a dose dependent manner (all P < 0.05). Thus, the ratio of TXB₂/6-keto-PGF_1α was significantly decreased (P < 0.05), while the ratio of t-PA/PAI-1 was significantly increased (P < 0.05). In addition, enhanced AT-III and PC activities indicated coagulation inactivation effects of EtOAc SDS root extracts. EtOAc extraction from SDS showed antithrombotic effects, which are likely due to platelet adhesion and aggregation inhibition as well as anticoagulant activities.