• BMB Reports
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• v.45 no.7
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• pp.390-395
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• 2012

Oleanolic acid (OA), a triterpenoid known for its anti-inflammatory and anti-cancer properties, is commonly present in several medicinal plants but its anticoagulant activities have not been studied. Here, the anticoagulant properties of OA were determined by monitoring activated partial thromboplastin time (aPTT), prothrombin time (PT), fibrin polymerization as well as cell-based thrombin and activated factor X (FXa) generation activities. Data showed OA prolonged aPTT and PT significantly and inhibited thrombin catalyzed fibrin polymerization. In addition, OA inhibited the activities of thrombin and FXa and inhibited the generation of thrombin or FXa in human endothelial cells. OA also inhibited TNF-${\alpha}$-induced tissue factor expression on human endothelial cells. In accordance with these anticoagulant activities, OA showed an anticoagulant effect in vivo. These results indicate that OA possesses antithrombotic activities and suggest that daily consumption of a herb containing OA may be preventing thrombosis in pathological states.

• The Korean Journal of Mycology
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• v.40 no.3
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• pp.159-163
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• 2012

This study was performed to investigate the biological activities of Hericium erinaceus fruiting body, including antioxidative, fibrinolytic, thrombin inhibitory and ${\alpha}$-glucosidase inhibitory activities. The water extract of H. erinaceus was fractionated into hexane, chloroform, ethyl acetate, butanol and water fractions, and each of these fractions was individually assayed. The water extract showed high antioxidative activity at 87.78%. The water fraction showed the highest extraction yield at 35.68% (w/w). In the fraction activity tests, butanol and water fractions showed strong antioxidative activities at 87.91% and 92.27%, respectively. Assays for fibrinolytic activity indicated that only the ethyl acetate fraction has significant efficacy at 2.96 plasmin units/mL. The 10-fold dilution of hexane fraction showed high thrombin inhibitory activity, and ${\alpha}$-glucosidase inhibitory activity at 77.67% and 90.53%, respectively. In conclusion, solvent fractions of H. erinaceus can be used as materials for the development of biofunctional foods to prevent cardiovascular diseases.

• Archives of Pharmacal Research
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• v.22 no.2
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• pp.119-123
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• 1999

Parathyroid hormone (PTH) treatment of bone and kidney-derived cells not only activates adenyly cyclase buy also increases intracellular free calcium, and translocates protein kinase C (PKC) from cytosol to plasma membranes. We have found that acute phorbol ester pretreatment significantly decreases PTH-induced calcium transients and the effect of phorbol ester was antagonized by staurosporine (ST). Although the major effect of ST in that study was the reversal of the action of phorbol ester, it appeared that ST may also have promoted the effect of PTH directly. To further investigate the observation, we examined the effect of ST on the intracellular calcium transients induced by PTH and $\alpha$-thrombin ($\alpha$-TH). For calcium transient experiments, UMR-106 cells were loaded with 2 mM fluo-acetoxymethylester for 30 min at room temperature. The cells were then washed and suspended in buffer containing 1 mM calcium. Fluorescence was detected at 530 nm, with excitation at 505 nm. ST alone did not cause calcium transients, but enhanced the transients elicited by PTH response. added 5 min before the hormone. Another protein kinase inhibitor H-7 likewise enhanced the calcium responses elicited by PTH, while genistein did not affect PTH response. Calcium transients elicited by $\alpha$-TH were also enhanced by ST. The results suggest that there might be tonically activated endogenous protein kinase(s) which inhibit calcium signaling of some calcemic agents.

• Biomedical Science Letters
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• v.18 no.1
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• pp.35-41
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• 2012

Physiological activities of hot water extract and solvent fractions isolated from Astragalus membranaceus were examined and the antioxidative, fibrinolytic, thrombin inhibitory and a-glucosidase inhibitory activity were measured. The hot water extract of Astragalus membranaceus was fractionated into hexane, chloroform, ethyl acetate, butanol and water fractions, and each of these fractions was individually assayed. The antioxidative activities of ethyl acetate and chloroform fractions were 89.96% and 87.36%, respectively. Using the fibrin plate method, only the hot water extract showed a plasmin activity of 0.41 units/ml. The thrombin inhibitory activity of the ethyl acetate fraction was the highest with a value of 82.73%. The hot water extract displayed a-glucosidase inhibitory activity of 64.91%. In conclusion, the hot water extract and the ethyl acetate fraction can be used as materials for the development of biofunctional foods to prevent cardiovascular diseases.

• Journal of Microbiology and Biotechnology
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• v.1 no.4
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• pp.266-273
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• 1991

Hirudin, a 65-amino acid protein isolated from the salivary gland of the bloodsucking leech, Hirudo medicinalis, is a potent thrombin-specific inhibitor and blocks the thrombin-mediated conversion of fibrinogen to fibrin in clot formation. We have studied the gene expression and secretion of hirudin in yeast. Saccharomyces cerevisiae. A gene coding for hirudin was synthesized based on the amino acid sequence and cloned into a yeast expression vector $YEG{\alpha}-1$ containing the ${\alpha}-mating$ factor pre-pro leader sequence and galactose-inducible promoter, GALl0. Recombinant S. cerevisiae was found to secrete biologically active hirudin into the extracellular medium. The secreted recombinant hirudin was recovered from the culture medium and purified with ultrafiltration and reverse phase high performance liquid chromatography. Approximately 1 mg of hirudin per liter was produced under suboptimal culture conditions and brought to about 90% purity in two steps of purification.

• BMB Reports
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• v.32 no.6
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• pp.567-572
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• 1999

We have previously shown that a DNA fragment is responsible for the anticoagulatory effect of an earthworm, Lumbricus rubellus. The anticoagluant increased the activated partial thromboplastin time (APTT) and also inhibited the thrombin activity observed with either N-${\alpha}$-p-tosyl-L-arginine methyl ester (TAME) or H-D-phenyl-alanyl-L-pipecoil-L-arginine-p-nitroanilide (S-2238). Since trypsin digestion of the anticoagulant further increased the APTT, the possible presence of a regulatory protein for the anticoagulatory DNA was investigated by digesting the anticoagulant with trypsin and isolating the DNA fragment with C4-reversed phase HPLC. The DNA fragment lacking a regulatory protein was eluted in the flow-through fraction, and analyzed with thrombin and activated factor X. Activated factor X activity was more strongly inhibited than thrombin activity. For DNA digestion, we treated the anticoagulant with DNase and purified the DNA-binding protein with a FPLC Resource-S cation exchange column. The regulatory protein, with an $M_r$ of 55.0 kDa, reduced the anticoagulatory effect of the DNA fragment.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.189-193
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• 2011

To investigate the physiological activities of hot water extract and solvent fractions isolated from Pleurotus ferulea, antioxidative, fibrinolytic, thrombin inhibitory, and ${\alpha}$-glucosidase inhibitory activities were examined. Pleurotus ferulea, hot water extract was fractionated into hexane, chloroform, ethyl acetate, butanol and water fraction. Each of these was assayed individually. The antioxidative activities of ethyl acetate and butanol fractions were 86.79% and 87.82%, respectively. Using the fibrin plate method, only the ethyl acetate fraction showed a plasmin activity of 0.08 units/ml. Thrombin inhibitory activities of chloroform and ethyl acetate fractions were 74.90% and 71.08%, respectively. In the ${\alpha}$-glucosidase inhibitory activity test, butanol fraction showed the highest activity at 49.67%. From the above results, we anticipate that solvent fractions of Pleurotus ferulea can be used as a materials for the development of biofunctional foods for cardiovascular diseases.

• Journal of Ginseng Research
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• v.40 no.4
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• pp.359-365
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• 2016

Background: Glycoprotein IIb/IIIa (${\alpha}aIIb/{\beta}_3$) is involved in platelet adhesion, and triggers a series of intracellular signaling cascades, leading to platelet shape change, granule secretion, and clot retraction. In this study, we evaluated the effect of ginsenoside Ro (G-Ro) on the binding of fibrinogen to ${\alpha}aIIb/{\beta}_3$. Methods: We investigated the effect of G-Ro on regulation of signaling molecules affecting the binding of fibrinogen to ${\alpha}aIIb/{\beta}_3$, and its final reaction, clot retraction. Results: We found that G-Ro dose-dependently inhibited thrombin-induced platelet aggregation and attenuated the binding of fibrinogen to ${\alpha}aIIb/{\beta}_3$ by phosphorylating cyclic adenosine monophosphate (cAMP)-dependently vasodilator-stimulated phosphoprotein (VASP; $Ser^{157}$). In addition, G-Ro strongly abrogated the clot retraction reflecting the intensification of thrombus. Conclusion: We demonstrate that G-Ro is a beneficial novel compound inhibiting ${\alpha}aIIb/{\beta}_3$-mediated fibrinogen binding, and may prevent platelet aggregation-mediated thrombotic disease.

• The Korean Journal of Mycology
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• v.40 no.4
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• pp.296-298
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• 2012

In this study, the biological activities of 33 kinds of wild mushroom methanol extracts were investigated. Boletellus elatus showed the greatest fibrinolytic activity (1.08 plasmin units/mL) in a fibrin plate assay, and the activity of Heterobasidion insulasis was 0.89 plasmin units. The thrombin inhibitory activities of Boletellus elatus and Heterobasidion insulasis were 93.32% and 93.69%, respectively. In a ${\alpha}$-glucosidase inhibitory activity test, Laccaria amethystina showed the greatest inhibitory activity at 81.25%. The antioxidative activities of Gomphus sp. and Geastrum lageniforme were 91.37% and 90.42%, respectively. Since Boletellus elatus and Heterobasidion insulasis have strong fibrinolytic and thrombin inhibitory and antioxidative activities, the two mushrooms can be used as material for the development of biofunctional foods for cardiovascular diseases.

• BMB Reports
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• v.29 no.6
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• pp.500-506
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• 1996

We have isolated a water-extracted novel regulator for blood coagulation from an earthworm, Lumbricus rubellus. As a folk remedy, the earthworm has been known to facilitate blood circulation. After complete heat inactivation of endogenous proteases in the earthworm, an anticoagulant(s) was purified through ammonium sulfate fractionation and three consecutive gel permeation chromatography of Sephacryl S-300, Sephadex G-75, and G-150 by measuring activated partial thromboplastin time (APTT) The anticoagulant was further purified to 2,800 fold with a C4 reversed-phase HPLC This activity was stable under heat ($100^{\circ}C$ for 30 min) and acidic conditions (0.4 N HCl). The effects of this partially purified anticoagulant on thrombin were observed with various substrates such as N${\alpha}$-benzoyl-DL-arginine-p-nitroanilide (BApNA), H-D-phenylalanyl-L-pipecoyl-L-arginine-p-nitroanilide (S-2238), N${\alpha}$-p-tosyl-L-arginine methyl ester (TAME), and fibrinogen as a natural substrate. Only TAME hydrolysis, due to an esterase activity of the enzyme, was inhibited among the chromogenic substrates. In addition, the anticoagulant not only inhibited the conversion of fibrinogen to fibrin but also prolonged the fibrin clot formation monitored with the in vitro coagulation test. Based on these observations, we suggest the significance of measuring the ability of antithrombotic drugs to inhibit the esterase activity of thrombin. In this report, it was also shown that the earthworm indeed contained a water-extractable, heat- and acid-stable anticoagulant which could be used as a novel antithrombotic agent.