Antithrombotic activities of aqueous extract from Radix Ophiopogon japonicus and its two constituents.

To provide further pharmacological evidence for its clinical use in thrombotic diseases, the antithrombotic activities of the aqueous extract of Radix Ophiopogon japonicus (ROJ-ext) were studied in mouse and rat models. The results showed that ROJ-ext remarkably decreased length of tail thrombus in mice at 48 h and 72 h after carrageenan injection at doses of 12.5 and 25.0 mg/kg. Meanwhile, ROJ-ext markedly inhibited thrombosis induced by arterial-venous (AV) shunt (silk thread) in rats at doses of 6.25 and 12.5 mg/kg. Furthermore, ROJ-ext and one of its components, ruscogenin, significantly inhibited platelet aggregation induced by adenosine diphosphate (ADP) in rats by oral administration of 12.5 mg/kg or 0.7 mg/kg for three times, however, ophiopogonin D 1.4 mg/kg only showed slight inhibition. On the other hand, ophiopogonin D (0.5-2.0 mg/kg, p.o.) and ruscogenin (0.25-1.00 mg/kg, p.o.) produced dose-related inhibition of venous thrombosis induced by tight ligation of the inferior vena cava for 6 h in mice by once oral administration. The findings of this study indicate that an aqueous extract of Radix Ophiopogon japonicus (ROJ-ext) exerted significant antithrombotic activity and ruscogenin and ophiopogonin D are two of its active components, which supported its therapeutic use for thrombotic diseases.