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

Abstract

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.

Figure 1

Flow chart of the rat experiments.

Figure 2

Extracts of SDS roots significantly inhibited FeCl₃-induced rat carotid artery thrombosis. (A) HE staining of rat carotid artery thrombosis in each group; (B) comparison of the thrombus weight in each group; (C) comparison of the ratio of thrombosis area in each group. Before the establishment of FeCl₃-induced rat carotid artery thrombosis models, the rats in each group were treated with the indicated solvent extract of SDS roots or CDDP for 20 days, once a day. n = 10, data are presented as the mean ± SD; Significant difference compare to model group *P < 0.05, and compre to sham group ^ΔP < 0.05.

Figure 3

Different doses of SDS root ESF suppressed FeCl₃-induced rat carotid artery thrombosis. (A) HE staining of rat carotid artery thrombosis in each group; (B) comparison of the rat thrombus weight in each group; (C) comparison of the ratio of thrombosis area in each group. Before the establishment of FeCl₃-induced rat carotid artery thrombosis models, rats in each group were treated with different doses of SDS root ESF or CDDP for 20 days, once a day, n = 10; data are presented as the mean ± SD; *P < 0.05, significant difference compared to the model group; ^ΔP < 0.05 compared to the sham group.

Figure 4

Effects of SDS root ESF on FeCl₃ induced rat plasma levels of TXB₂ and 6-keto-PGF_1α. (A) TXB₂/6-keto-PGF_1α ratio; (B) and vWF (C). Before the establishment of FeCl₃-induced rat carotid artery thrombosis models, rats in each group were lavaged with different doses of SDS root EtOAc extract or CDDP for 20 days, once a day. n = 10; data are presented as the mean ± SD; *P < 0.05, significant difference compared to the model group; ^ΔP < 0.05 compared to the sham group.

Figure 5

Effects of SDS root EtOAc extracts on FeCl₃-induced rat plasma levels of PC. (A) and AT-III (B). Before the establishment of the FeCl₃-induced rat carotid artery thrombosis models, rats in each group were treated with different doses of SDS root EtOAc extract or CDDP for 20 days, once a day, n = 10; data are presented as the mean ± SD; *P < 0.05, significant difference compared to the model group; ^ΔP < 0.05 compared to the sham group.

Figure 6

Effect of SDS root ESF on the activity of the fibrinolytic system. Influences of each dose of EtOAc extract on FeCl₃-induced rat plasma levels of (A) t-PA and PAI-1, (B) t-PA/PAI-1 ratios and (C) PLG. Before the establishment of FeCl₃-induced rat carotid artery thrombosis models, rats in each group were treated with different doses of SDS root EtOAc extract or CDDP for 20 days, once a day, n = 10; data are presented as the mean ± SD; *P < 0.05, significant difference compared to the model group; ^ΔP < 0.05 compared to the sham group.