• Journal of Food Hygiene and Safety
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• v.19 no.3
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• pp.161-166
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• 2004

We investigated the antiplatelet effect of a newly synthesized guanidine derivative KR-32558, a sodium-hydrogen exchanger-1 (NHE-1) inhibitor, together with the elucidation of the possible mechanisms of action. KR-32558 concentration -dependently inhibited the aggregation of washed rabbit platelets induced by collagen (10 ${\mu}g/ml$) with an $IC_{50}$ value of 85.9 ${\mu}M$, but with much weaker potency against aggregation induced by thapsigargin (0.5 ${\mu}M$) or A23187 (5 ${\mu}M$). And had no effect on platelet aggregation induced by arachidonic acid (100 ${\mu}M$), thrombin (0.05 U/ml) and U46619 (1 ${\mu}M$) up to 100 ${\mu}M$. KR-32558 completely inhibited the $[Ca^{2+}]_i$ mobilization induced by collagen at concentration of 100${\mu}iM$. Taken together, these observation suggest that KR-32558 selectively inhibited collagen-mediated platelet aggregation by blocking the cytoplasmic calcium mobilization in addition to NHE-1 inhibition.

• Biomedical Science Letters
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• v.24 no.3
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• pp.280-284
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• 2018

The incidence of cardiovascular diseases (CVDs) is increasing rapidly in developed countries, with CVDs now representing the leading cause of morbidity and mortality. Natural products and ethnomedicines have been shown to reduce the risk of CVDs. Garlic is a medicinal plant used throughout the world for its anti-inflammatory, antioxidant, and antiplatelet activities. Chitosan is a natural polysaccharide obtained from chitin, and derivatives of chitosan have been shown to inhibit platelet aggregation and adhesion. We hypothesized that fermented preparations of these products may possess stronger antiplatelet effects than the non-fermented forms owing to the increased bioavailability of the bioactive compounds produced during fermentation. Therefore, we compared these compounds via in vitro and ex vivo platelet aggregation assays by using standard light transmission aggregometry and ex vivo granule secretions from rat platelets. We found that fermented preparations exerted more potent and significant inhibition of platelet aggregation both in vitro and ex vivo. Likewise, ATP release from dense granules of platelets was also significantly inhibited in fermented preparation-treated rat platelets compared to that in non-fermented preparation-treated ones. We concluded that fermented preparations exerted more potent effects on platelet function both in vitro and ex vivo, possibly as a result of the increased bioavailability of active compounds produced during fermentation. We therefore suggest that fermented products may be potent therapeutics against platelet-related CVDs and can be used as antiplatelet and antithrombotic agents.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.69-69
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• 1997

In the screening of tropical medicinal plants using PAE receptor binding assay, the ether extract of Ardisia crispa showed the potent antagonistic activity. Ardisia crispa have been used to heal the scurf, earache, orchitis, fever and diarrhoea, cough and given to the mother after childbirth to ‘wash out dirty blood’ in Malaysia. By means of activity guided isolation, compound AC7-1 was isolated as the potent PAF antagonist. In this study, antiplatelet effects of compound AC7-1 were examined in vitro platelet aggregation assay using the chronolog aggregometer. Compound AC7-1 inhibited PAF-, collagen-, ADP-, thrombin-induced platelet aggregation in human, rabbit and rat platelet rich plasma. In vitro rabbit platelet aggregation, the IC$\_$50/ value of compound AC7-1 was 5 ${\times}$ 10$\^$-6/ M against PAF(5 ${\times}$ 10$\^$-7/M)-induced aggregation. The IC$\_$50/ values of AC7-1 on PAF-induced platelet aggregation increased with increase of the concentration of PAF used. This result suggested the competitive nature of the AC7-1 antagonism. In vitro rat platelet aggregation, the IC$\_$50/ values of AC7-1 on collagen-, ADP-induced platelet aggregation were 4 ${\times}$ 10$\^$-6/ M, 2 ${\times}$ 10$\^$-5/ M, respectively. Also in vitro human platelet aggregation, AC7-1 potently inhibited both the primary phase and secondary phase of thrombin-induced aggregation.

• Journal of Korean Foot and Ankle Society
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• v.18 no.4
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• pp.159-164
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• 2014

Purpose: The purpose of this study is to confirm the effect of antiplatelet drugs in diabetic peripheral vasculopathy in diabetic foot patients. Materials and Methods: We designed a retrospective study in diabetic foot patients with diabetic peripheral vasculopathy. From October 2007 to December 2013, 278 cases in 139 patients who took antiplatelet drugs over at least a six-month period were included in this study. We categorized these patients according to the type of drug used. The efficacy of antiplatelet drugs was evaluated using anklebrachial index (ABI) and pulse wave velocity (PWV). Results: Only the aspirin group showed a statistically significant increase of ABI after antiplatelet therapy ($1.10{\pm}0.12$ to $1.12{\pm}0.11$). In addition, only the cilostazol group showed a statistically significant decrease of PWV after antiplatelet therapy ($1,701.20{\pm}396.56$ to $1,627.42{\pm}324.98$). Conclusion: Aspirin and cilostazol may be used in treatment of diabetic peripheral vasculopathy, whereas dual antiplatelet therapy with aspirin and clopidogrel has no specific benefits in diabetic peripheral vasculopathy.

• Biomolecules & Therapeutics
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• v.24 no.6
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• pp.659-664
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• 2016

Lindera obtusiloba has been used in traditional herbal medicine for the treatment of blood stasis and inflammation. The leaves of Lindera obtusiloba have been reported to exhibit various physiological activities. However, there is little information available on their antiplatelet and antithrombotic activities. Thus, the present study aimed to evaluate the effect of Lindera obtusiloba leaf extract (LLE) on platelet activities, coagulation and thromboembolism. In a platelet aggregation study, LLE significantly inhibited various agonist-induced platelet aggregations in vitro and ex vivo. Furthermore, LLE significantly inhibited collagen-induced thromboxane A2 (TXA2) production in rat platelets. In addition, oral administration of LLE was protective in a mouse model of pulmonary thromboembolism induced by intravenous injection of a mixture of collagen and epinephrine. Interestingly, LLE did not significantly alter prothrombin time (PT) and activated partial thromboplastin time (aPTT). This study indicates that the antithrombotic effects of LLE might be due to its antiplatelet activities rather than anticoagulation. Taken together, these results suggest that LLE may be a candidate preventive and therapeutic agent in cardiovascular diseases associated with platelet hyperactivity.

• Archives of Pharmacal Research
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• v.29 no.10
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• pp.898-903
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• 2006

The antiplatelet and antithrombotic activities of Korean Red Ginseng (KRG) were examined on rat carotid artery thrombosis in vivo, and platelet aggregation in vitro and ex vivo. Administration of KRG to rats not only prevented carotid artery thrombosis in vivo in a dose-dependent manner, but also significantly inhibited ADP- and collagen-induced platelet aggregation ex vivo, while failed to prolong coagulation times such as activated partial thromboplastin time (APTT) and prothrombin time (PT), indicating the antithrombotic effect of KRG might be due to its anti platelet aggregation rather than anticoagulation effect. In line with the above observations, KRG inhibited U46619-, arachidonic acid-, collagen- and thrombin-induced rabbit platelet aggregation in vitro in a concentration-dependent manner, with $IC_{50}$ values of $620{\pm}12$, $823{\pm}22$, $722{\pm}21$ and $650{\pm}14\;{\mu}g/mL$, respectively. Accordingly, KRG also inhibited various agonists-induced platelet serotonin secretions as it suppressed platelet aggregation. These results suggest that KRG has a potent antithrombotic effect in vivo, which may be due to antiplatelet rather than anticoagulation activity, and KRG intake may be beneficial to the individuals with high risks of thrombotic and cardiovascular diseases.

• The Journal of Korean Medicine
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• v.21 no.4
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• pp.37-46
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• 2000

Objective : The purpose of this study was to investigate the effects of Angelicae Gigantis Radix on brain damage and the cardiovascular system. Method : By administration Angelicae Gigantis Radix, we compared treated groups with not treated groups, in view of five points as follows $\circled1$ the intervascular eNOS, $\circled2$ the blood pressure of SHR, $\circled3$ the transcription of the Kir6.2, $\circled4$ the survival time of the rats when common carotid artery was ligated, and $\circled5$ antiplatelet aggregation. Result : In this experiment, Angelicae Gigantis Radix treated group showed significant produced in the intervascular eNOS and decreased the blood pressure of SHR, increased the transcription of the Kir6.2 and SUR significantly in all Treated groups, prolonged the survival time of the rats when common carotid artery, showed the effects on antiplatelet aggregation. Conclusion : According to the above results, Angelicae Gigantis Radix can protect the brain damage and have cardiovascular system effect.

• Proceedings of the PSK Conference
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• 2000.04a
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• pp.122.2-123
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• 2000

• Biomedical Science Letters
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• v.22 no.4
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• pp.127-139
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• 2016

A species of the fungal genus Cordyceps has been used as an ingredient of traditional Chinese medicine. In this study, we prepared cordycepin-enriched WIB-801CE, an ethanol extract from culture solution of Cordyceps militaris-hypha, and evaluated its antiplatelet effects on human platelet aggregation. WIB-801CE dose-dependently inhibited ADP-, collagen-, and thrombin-induced platelet aggregation. These antiplatelet effects by WIB-801CE were associated with the attenuation of thromboxane $A_2$ ($TXA_2$) production and serotonin release by ADP, collagen, and thrombin. The inhibition of $TXA_2$ production by WIB-801CE was due to the inhibition of cyclooxygenase-1, $TXA_2$ synthase, and cytosolic phospholipase $A_2$ activity. Therefore, these data suggest that WIB-801CE may be a beneficial component against protection from platelet aggregation-mediated thrombotic disease.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.168-173
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• 2012

We performed this study to develop antithrombotic agents from oriental medicine herb extracts. Polygonum cuspidatum has been traditionally used as an edible medical resources for the treatment of cancer, pyodermatitis, hepatitis, cystitis, and inflammation. However, the effects of Polygonum cuspidatum on thrombosis and platelet activation are not precisely understood. The antithrombotic and antiplatelet activities of Polygonum cuspidatum were investigated by assessing the effect of a 70% ethanol extract of Polygonum cuspidatum on blood coagulation, fibrinolysis, and platelet aggregation. Polygonum cuspidatum showed effective fibrinolytic activity at 10 mg/mL. Polygonum cuspidatum also inhibited adenosine diphosphate induced platelet aggregation. Furthermore, evaluation of anticoagulant activity showed that an extract of Polygonum cuspidatum prolonged coagulation time via activated partial thromboplastin time (APTT). Our results show that Polygonum cuspidatum can be a potential candidate for antiplatelet activity as well as a fibrinolytic agent.