• Natural Product Sciences
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• v.9 no.4
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• pp.270-272
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• 2003

The methanol extract of Euphorbia milii exhibited strong inhibitory effect on platelet aggregation in the cource of our search for anti-platelet component from succulent plants. Two components, components 1 and 2 were isolated from this plant. 1 was the mixture of 72% of 1-octacosanol (1a) and 28% of 1-triacontanol (1b), and 2 was identified as ${\beta}-sitosterol$. 2 ($IC_{50}$: $195\;{\mu}M$, and $170\;{\mu}M$ respectively) was about two fold stronger than ASA ($IC_{50}$: $420\;{\mu}M$ and $340\;{\mu}M$ respectively) on both collagen and U46619 induced aggregation, while the effect of 1 to platelets was negligible.

• Korean Journal of Pharmacognosy
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• v.26 no.1
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• pp.74-77
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• 1995

Several coumarins isolated from Angelica sp. were described to show inhibitory effects against human platelet aggregation. The anti-thrombotic and anti-platelet potential was evaluated, in this paper, with the BuOH soluble fraction of Angelica dahurica root. The BuOH fraction was divided into five subfractions fr. A - E and tested in the mouse model of thrombosis. Survival was enhanced to 35% with fr. A or fr. E treated (500 mg/Kg, p.o.) group of mice compared with 5% survival of the control group. However, none of the 8 coumarin glycosides obtained from fr. A, at the conc. of 0.5 mg/ml, showed inhibitory effects against rat platelet aggregation induced by ADP or collagen.

• Toxicological Research
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• v.20 no.2
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• pp.137-142
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• 2004

We investigated the effects of plant vinegar on platelets and blood coagulation system. Plant vinegar inhibited in vitro platelet aggregation in a concentration dependent manner, when platelets were activated by thrombin and collagen. In addition, plant vinegar showed inhibitory effects on the serotonin secretion induced by thrombin in a concentration dependent manner. However, treatment with plant vinegar to platelets did not induce any cytotoxicity, as determined by the release of lactate dehydrogenase. Plant vinegar did not change the coagulation parameters such as activated partial thromboplastin time (aPTT) and prothrombin time (PT) using rat citrated plasma. In vivo study revealed that, treatment with plant vinegar prolonged the bleeding time from mouse tail. All these results suggest that plant vinegar might improve blood hemostasis mediated via anti platelet activities.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.380.3-380.3
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• 2002

Rhus verniciflua Stokes (RVS) is a widely used herbal plant with various biological properties. Our previous study using in vitro platelet aggregation in whole blood showed that ethyl acetate layer of RVS had strong anti-aggregatory activity. In this study. to investigate the anti-aggregatory activity and antioxidative effects of RVS ethyl acetate layer. the layer was subsequently fractionated by ODS columm chromatograph (50% MeOH). As a result. the fraction 3 was most inhibited the aggregation of platelet in rat whole blood induced by thrombin and all fraction of RVS was detected strong antioxidative effect. (omitted)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.336.2-336.2
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• 2002

Several 1 A-naphthoquinone derivatives have been reported to possess many pharmacological effects such as anti-viral. anti-fungal. anti-cancer and anti-platelet activities. We have reported that 2-chloro-3-［4-(ethyICarbOxy)-phenyl］-amino-1.4-naphthoquinone(NQ12) had a potent inhibitory effect on the platelet aggregation in vitro and thrombosis in vivo. However. little has been known about functional roleot NQ12 on vascular smooth muscle cells (VSMCs). (omitted)

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.140.2-140.2
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• 2001

• Translational and Clinical Pharmacology
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• v.26 no.4
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• pp.160-165
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• 2018

Indobufen ($Ibustrin^{(R)}$), a reversible inhibitor of platelet aggregation, exists in two enantiomeric forms in 1:1 ratio. Here, we characterized the anti-platelet effect of S- and R-indobufen using response surface modeling using $NONMEM^{(R)}$ and predicted the therapeutic doses exerting the maximal efficacy of each enantioselective S- and R-indobufen formulation. S- and R-indobufen were added individually or together to 24 plasma samples from drug-naïve healthy subjects, generating 892 samples containing randomly selected concentrations of the drugs of 0-128 mg/L. Collagen-induced platelet aggregation in platelet-rich plasma was determined using a Chrono-log Lumi-Aggregometer. Inhibitory sigmoid $I_{max}$ model adequately described the anti-platelet effect. The S-form was more potent, whereas the R-form showed less inter-individual variation. No significant interaction was observed between the two enantiomers. The anti-platelet effect of multiple treatments with 200 mg indobufen twice daily doses was predicted in the simulation study, and the effect of S- or R-indobufen alone at various doses was predicted to define optimal dosing regimen for each enantiomer. Simulation study predicted that 200 mg twice daily administration of S-indobufen alone will produce more treatment effect than S-and R-mixture formulation. S-indobufen produced treatment effect at lower concentration than R-indobufen. However, inter-individual variation of the pharmacodynamic response was smaller in R-indobufen. The present study suggests the optimal doses of R-and S-enantioselective indobufen formulations in terms of treatment efficacy for patients with thromboembolic problems. The proposed methodology in this study can be applied to the develop novel enantio-selective drugs more efficiently.

• Korean Journal of Pharmacognosy
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• v.53 no.2
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• pp.64-69
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• 2022

When blood vessels are damaged, a rapid hemostatic response should occur in order to lower blood loss and keep normal circulation, and platelet activation and aggregation are essential. Nevertheless, abnormal or excessive platelet aggregation can be a reason of cardiovascular diseases including thrombosis, atherosclerosis, and stroke. Therefore, the screening for a substance which can regulate platelet activation and suppress aggregation reaction is very important for treatment and prevention of cardiovascular diseases. Artemether is a methyl ether derivative of artemisinin, which is isolated from the antimalarial plant Artemisia annua, but research on platelet aggregation or its mechanisms is still insufficient. This study identified the effects of artemether on U46619-induced human platelet aggregation and their granule secretion (ATP and serotonin release). In addition, the effects of artemether on the phosphorylation of PI3K/Akt or MAPK, which are related to signal transduction in platelet aggregation, were studied. As the results, artemether significantly lowered PI3K/Akt and MAPK phosphorylation, which inhibited platelet aggregation through granule secretion (ATP and serotonin release) dose-dependently. Therefore, we suggest that artemether is an antiplatelet substance that regulates PI3K/Akt and MAPK pathway and is of value as a therapeutic and preventive agent for platelet-derived cardiovascular diseases.

• Korean Journal of Clinical Pharmacy
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• v.2 no.1
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• pp.1-9
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• 1992

Protective effect of urokinase on reperfusion were studied followed by global ischemia in the isolated perfused rat heart. Separately, anti-platelet aggregation effect of urokinase also investigated. Urokinase exhibited positive effect for the protection of rat heart function by increasing the LV dp/dt, coronary flow(CF) and the Tate pressure product(RPP), and by decreasing the LVEDP on reperfusion. Urokinase also decreased arrhythmia by $74.7\%(P<0.05) induced by global ischemia in the rat heart. In the platelet aggregation study, urokinase did not show the inhibitory effect of ADP or collagen induced platelet aggregation inviuo and exvivo.

• Korean Journal of Oriental Medicine
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• v.13 no.2 s.20
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• pp.143-148
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• 2007

The present study examined inhibitory effects of 20 efficient experience prescriptions on platelet aggregation induced by collagen in human whole blood using the impedance method of aggregometry. Among them, a hot water extract of KIOM 2003-080 was selected to be the most effective candidate. In an in vivo study using a mouse acute thrombosis model, the anti-thrombotic effects of the KIOM2003-080 crude extract were also observed. In addition, we accessed bio-marker of platelet activation using thromboxane B2 by ELISA assay. A significantly decrease in thromboxane B2 production was seen in the presence of KIOM2003-080. Consequently, the results from this experiment provide pharmacological evidence for the traditional use of KIOM2003-080 prescription, suggesting that its hot water extracts could be used to prevent platelet aggregation and thrombosis disease.