• Journal of Applied Biological Chemistry
• /
• 제66권
• /
• pp.171-178
• /
• 2023

Morus alba, a popular medicinal plant belonging to the family Moraceae, has long been used commonly in traditional medicine and has various physiological activities, including antidiabetic, anti-microbial, diuretic, anti-oxidant, and anti-cancer activities. Morusinol was isolated from the root bark of M. alba; however, its biological effects have not yet been reported. Therefore, we examined the inhibitory effects of morusinol on human platelet aggregation, Ca²⁺ mobilization, and αIIb/β₃ activity. Our data showed that collagen-induced human platelet aggregation was inhibited by morusinol without cytotoxicity. In this study, we examined whether morusinol inhibits platelet aggregation through the regulation of integrin αIIb/β₃ and its associated signaling molecules. We observed that morusinol inhibited αIIb/β₃ activation by regulating vasodilator-stimulated phosphoprotein, phosphatidylinositol-3 kinase, Akt (protein kinase B), and glycogen synthase kinase-3α/β. These results show that morusinol inhibited fibronectin adhesion, fibrinogen binding, and clot retraction. Taken together, morusinol shows strong antiplatelet and anti-clot retraction effects and is a potential therapeutic drug candidate to prevent platelet-related thrombosis and cardiovascular disease.

• Food Science and Biotechnology
• /
• 제15권5호
• /
• pp.763-767
• /
• 2006

The anticoagulant properties of compounds derived from fennel (Foeniculum vulgare Gaertner) fruits were evaluated using a platelet aggregometer and compared with aspirin. The active constituents of fennel fruits were isolated and identified as (+)-fenchone and extragole by various spectral analysis techniques. With regard to the 50% inhibitory concentration ($IC_{50}$), (+)-fenchone effectively inhibited platelet aggregation induced by treatment with collagen ($IC_{50}$, $3.9\;{\mu}M$) and arachidonic acid (AA) ($IC_{50}$, $27.1\;{\mu}M$), and estragole inhibited collagen-induced platelet aggregation ($IC_{50}$, $4.7\;{\mu}M$). By way of comparison, (+)-fenchone and estragole proved to be significantly more potent than aspirin at inhibiting platelet aggregation induced by collagen. The inhibitory activity of (+)-fenchone toward platelet aggregation induced by AA was 1.3 times stronger than that of aspirin. These results indicate that (+)- fenchone and estragole may be useful as lead compounds for inhibiting platelet aggregation induced by arachidonic acid and collagen.

• 약학회지
• /
• 제43권6호
• /
• pp.809-817
• /
• 1999

The effect of 2-(4-cyanophenyl)amino-1,4-naphthalenedione-3-pyridinium perchlorate (PQ5) on pla-telet aggregation and its action mechanisms were investigated with rat platelet. PQ5 inhibited the platelet aggregation induced by collagen ($6{\;}{\mu\textrm{g}}/ml$), thrombin (0.4 U/ml) and A23187 ($3{\mu}M$) in concentration-dependent manner with $IC_{50}$ values of 5.50, 25.89 and $37.12{\;}{\mu}M$, respectively. PQ5 also significantly reduced the thromboxane $A_2$ (TXA2) formation in a concentration dependent manner. The collagen-induced arachidonic acid (AA) release in [-3H]-AA incorporated platelet, an indication of the phospholipase $A_2$ activity, was decreased by PQ5 pretreatment PQ5 significantly inhibited the activity of thormboxane synthase only at high concentration ($100{\mu}M$), but did not affect the cyclooxygenase activity at all. Collagen-induced ATP release was significantly reduced by PQ5. Calcium-induced platelet aggregation experiment suggests that the elevation of intracellular free $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) by collagen stimulation is decreased by the pretreatment of PQ5, which is due to the inhibition of calcium release from intracellular store and influx from outside of the cell. PQ5 did not showed the effect of anticoagulation as prothrombin time (PT) or activated partial thromboplastin time (APTT). Form these results, it is suggested that PQ5 exerts its antiplatelet activity through the inhibition of the intracellular $Ca^{2+}$ mobilization and the decrease of the $TXA_2$ synthesis.

• 대한의생명과학회지
• /
• 제25권2호
• /
• pp.123-130
• /
• 2019

Platelet aggregation is essential for hemostatic process in case of blood vessels damages. However, excessive platelet aggregation can cause cardiovascular disorders including atherosclerosis, thrombosis and myocardial infarction. Scopoletin is usually found in the roots of genus Scopolia or Artemisia, and is known to have anticoagulant and anti-malarial effects. This study investigated the effect of scopoletin on human platelet aggregation induced by U46619, an analogue of thromboxane $A_2(TXA_2)$. Scopoletin had anti-platelet effects by down-regulating $TXA_2$ and intracellular $Ca^{2+}$ mobilization ($[Ca^{2+}]_i$), the aggregation-inducing molecules generated in activated platelets. On the other hand, scopoletin increased the levels of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), which are known to be intracellular $Ca^{2+}$ antagonists. This resulted in inhibition of fibrinogen binding to ${\alpha}IIb/{\beta}_3$ in U46619-induced human platelet aggregation. In addition, scopoletin inhibited the release of adenosine trisphosphate (ATP) in dose-dependent manner. This result means that the aggregation amplification activity through the granule secretion in platelets was suppressed by scopoletin. Therefore, we demonstrated that scopoletin has a potent antiplatelet effect and is highly likely to prevent platelet-derived vascular disease.

• 생약학회지
• /
• 제52권3호
• /
• pp.127-133
• /
• 2021

Platelet activation plays a major role in cardiovascular disorders (CVDs). Thus, disrupting platelet activation represents an attractive therapeutic target on CVDs. Esculetin, a bioactive 6,7-dihydroxy derivative of coumarin, possesses pharmacological activities against obesity, diabetes, renal failure, and CVDs. In other report, the effect of esculetin has been examined in human platelet activation and experimental mouse models, and esculetin inhibited collagen- and arachidonic acid-induced platelet aggregation in washed human platelets. However, it had no effects on other agonists such as thrombin and U46619, and its mechanism is not also clearly known. This study investigated the effect of esculetin on collagen-induced human platelet aggregation, and we clarified the mechanism. Esuletin has effects on the down regulation of PI3K/Akt and MAPK, phosphoproteins that act in the signaling process in platelet aggregation. The effects of esculetin reduced of TXA₂ production and phospholipase A₂ activation, and intracellular granule secretion including ATP and serotonin, leading to inhibit platelet aggregation. These results clearly clarified the effect of esculetin in inhibiting platelet activity and thrombus formation in humans.

• 대한수의학회지
• /
• 제55권4호
• /
• pp.233-240
• /
• 2015

Although the effects of the rice bran have recently been investigated, there is no information regarding platelet physiology available. However, it is well known that fermented natural plants have a beneficial effect on cardiovascular diseases. Therefore, this study was conducted to investigate whether fermented rice bran extract (FRBE) with several plants (Artemisia princeps, Angelica Gigantis Radix, Cnidium officinale, and Camellia sinensis) affected agonist-induced platelet aggregation, and if so, what the underlying mechanism of its activity was. We performed several experiments, including in vitro platelet aggregation, intracellular calcium concentration and adenosine triphosphate release. In addition, the activation of integrin ${\alpha}_{II}b{\beta}3$ was determined using fibrinogen binding. Thrombus formation was also evaluated in vivo using an arterio-venous shunt model. The FRBE inhibited collagen-induced platelet aggregation in a concentration-dependent manner. FRBE significantly and dose dependently attenuated thrombus formation using rat arterio-venous shunt. FRBE suppressed the intracellular calcium mobilization in collagen-stimulated platelets. We also found that FRBE inhibited extracellular stimuli-responsive kinase 1/2, p38-mitogen-activated protein kinases and c-Jun N-terminal kinase phosphorylation. These results suggested that FRBE inhibited collagen-induced platelet aggregation, which was mediated by modulation of downstream signaling molecules. In conclusion, FRBE could be developed as a functional food against aberrant platelet activation-related cardiovascular diseases.

• Journal of Ginseng Research
• /
• 제41권1호
• /
• pp.96-102
• /
• 2017

Background: Korean ginseng, Panax ginseng Meyer, has been used as a traditional oriental medicine to treat illness and promote health for several thousand years. Ginsenosides are the main constituents for the pharmacological effects of P. ginseng. Since several ginsenosides, including ginsenoside (G)-Rg3 and G-Rp1, have reported antiplatelet activity, here we investigate the ability of G-Rp4 to modulate adenosine diphosphate (ADP)-induced platelet aggregation. The ginsenoside Rp4, a similar chemical structure of G-Rp1, was prepared from G-Rg1 by chemical modification. Methods: To examine the effects of G-Rp4 on platelet activation, we performed several experiments, including antiplatelet ability, the modulation of intracellular calcium concentration, and P-selectin expression. In addition, we examined the activation of integrin ${\alpha}IIb{\beta}_3$ and the phosphorylation of signaling molecules using fibrinogen binding assay and immunoblotting in rat washed platelets. Results: G-Rp4 inhibited ADP-induced platelet aggregation in a dose-dependent manner. We found that G-Rp4 decreased calcium mobilization and P-selectin expression in ADP-activated platelets. Moreover, fibrinogen binding to integrin ${\alpha}IIb{\beta}_3$ by ADP was attenuated in G-Rp4-treated platelets. G-Rp4 significantly attenuated phosphorylation of extracellular signal-regulated protein kinases 1 and 2, p38, and c-Jun N-terminal kinase, as well as protein kinase B, phosphatidylinositol 3-kinase, and phospholipase C-${\gamma}$ phosphorylations. Conclusion: G-Rp4 significantly inhibited ADP-induced platelet aggregation and this is mediated via modulating the intracellular signaling molecules. These results indicate that G-Rp4 could be a potential candidate as a therapeutic agent against platelet-related cardiovascular diseases.

• 한국식품영양과학회지
• /
• 제41권2호
• /
• pp.168-173
• /
• 2012

항혈전 효능을 탐색하기 위하여 한약재의 호장근 추출물로 혈전 용해능 활성과 혈액 응고시간 지연효과 즉 PT(prothrombin time), APTT(activated partial thromboplastin time)와 혈소판 응집억제 활성 등에 대해 항혈전 효능을 평가하였다. 혈전용해도를 측정하는 fibrin plate가 용해되어 형성된 투명환의 넓이를 측정하는 실험을 진행한 결과 혈전 용해도가 농도의존적으로 탁월한 효능을 나타내었다. 혈액응고 cascade에 미치는 영향을 알아보기 위해 혈액 응고시간 지연 및 단축 효과를 확인하고자 APTT와 PT에 미치는 영향을 조사한 결과 PT의 경우 대조군보다 단축됨을 보였다. APTT의 경우 농도의존적으로 우수한 지연효과를 보였다. 혈소판의 응집에 따라 형성되는 두 전극 사이에 형성된 전기적 저항의 변화로 나타나는 실험을 시행한 결과 호장근의 ADP로 유도한 결과에서 뛰어난 응집억제 활성을 보였다. 따라서 호장근을 향후에 혈전 질환의 치료제 개발에 효과적으로 이용될 수 있을 것으로 사료된다.

• Biomolecules & Therapeutics
• /
• 제7권3호
• /
• pp.227-233
• /
• 1999

The effects of 2-bromo-3-(3,5-tert-butyl-4-hydroxylphenyl)-1,4-naphthalenedione(TPN2), a synthetic vitamin K derivative, on platelet aggregation and its action mechanisms were investigated in rat platelet. TPN2 inhibited the platelet aggregation induced by collagen($10\mu\textrm{g}$/ml), thrombin(0.1 U/ml), A23187($10\mu\textrm{M}$) and arachidonic acid($100\mu\textrm{M}$) in concentration-dependent manner with $IC_{50}$ values of 6.5$\pm$1.3, 59.3$\pm$4.5, 13.0$\pm$2.37 and 2.9$\pm$$1.0\mu\textrm{M}$, respectively. Collagen-induced serotonin release was significantly reduced by TPN2. The elevation of intracellular free $Ca^{2+}$ concentration ([$Ca^{2+}$]i) by collagen stimulation was greatly decreased by the pretreatment of TPN2, which was due to the inhibition of calcium release from intracellular store and influx from outside of the cell. TPN2 also significantly reduced the thromboxane $A_2$($TXA_2$) formation in a concentration-dependent manner. The collagen-induced arachidonic acid (AA) release in [$^3H$]-AA incorporated platelet, an indicative of the phospholipase $A_2$ activity, was decreased by TPN2 pretreatment. TPN2 significantly inhibited the activity of thromboxane synthase, but did not affect the cyclooxygenase activity. From these results. it is suggested that TPN2 exert its antiplatelet activity through the inhibition of the intra-cellular $Ca^{2+}$ mobilization and the decrease of the $TXA_2$ synthesis.

• 한국약용작물학회지
• /
• 제13권4호
• /
• pp.178-181
• /
• 2005

15종의 항어혈성 중국 약용식물의 추출물에 대하여 PAF 수용체 결합 억제활성을 검색한 결과 4종의 약용식물, Campsis grandiflora, Dalbergia odorifera, Zanthoxylum nitidum, Vaccaria segetalis에서 50% 이상의 강한 PAF 결합 저해 활성이 나타났다.