• Korean Journal of Pharmacognosy
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• v.29 no.3
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• pp.149-154
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• 1998

Binding of urokinase-type plasminogen activator to its cellular receptor accelerate production of plasmin from plasminogen on the cell surface. Plasmin can digest extracellular matrix components and basement membranes through activating certain proMMPs, which is related to the invasiveness to the cells. Plasmin also acts the regulation of blood coagulation and relates closely to cardiovascular diseases such as stroke and coronary occlusion. Therefore, its inhibitors may be useful as antimetastatic agents and to the treatment of cardiovascular diseases. To search for plasmin inhibitors from plant resources, we screened plasmin inhibitory activities with 76 methanol extract of plant species. Among them, three plant samples showed strong inhibitory activities (>70%) and thirteen plant samples showed more than 50% inhibitory activities of plasmin. Their inhibitory activities were not directly related with uPA inhibitory activites and cell viability.

• The Korean Journal of Physiology and Pharmacology
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• v.14 no.6
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• pp.385-390
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• 2010

Excessive extracellular matrix (ECM) accumulation is the main feature of chronic renal disease including diabetic nephropathy. Plasminogen activator inhibitor (PAI)-1 is known to play an important role in renal ECM accumulation in part through suppression of plasmin generation and matrix metalloproteinase (MMP) activation. The present study examined the effect of PAI-1 antisense oligodeoxynucleotide (ODN) on fibronectin upregulation and plasmin/MMP suppression in primary mesangial cells cultured under high glucose (HG) or transforming growth factor (TGF)-${\beta}1$, major mediators of diabetic renal ECM accumulation. Growth arrested and synchronized rat primary mesangial cells were transfected with $1\;{\mu}M$ phosphorothioate-modified antisense or control mis-match ODN for 24 hours with cationic liposome and then stimulated with 30 mM D-glucose or 2 ng/ml TGF-${\beta}1$. PAl-1 or fibronectin protein was measured by Western blot analysis. Plasmin activity was determined using a synthetic fluorometric plasmin substrate and MMP-2 activity analyzed using zymography. HG and TGF-${\beta}1$ significantly increased PAI-1 and fibronectin protein expression as well as decreased plasmin and MMP-2 activity. Transient transfection of mesangial cells with PAI-1 antisense ODN, but not mis-match ODN, effectively reversed basal as well as HG- and TGF-${\beta}1$-induced suppression of plasmin and MMP-2 activity. Both basal and upregulated fibronectin secretion were also inhibited by PAI-1 antisense ODN. These data confirm that PAI-1 plays an important role in ECM accumulation in diabetic mesangium through suppression of protease activity and suggest that PAI-1 antisense ODN would be an effective therapeutic strategy for prevention of renal fibrosis including diabetic nephropathy.

• Molecules and Cells
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• v.24 no.2
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• pp.240-246
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• 2007

The ${\beta}2$ integrins on leukocytes play important roles in cell adhesion, migration and phagocytosis. One of the ${\beta}2$ integrins, ${\alpha}X{\beta}2$ (CD11c/CD18), is known to bind ligands such as fibrinogen, Thy-1 and iC3b, but its function is not well characterized. To understand its biological roles, we attempted to identify novel ligands. The functional moiety of ${\alpha}X{\beta}2$, the ${\alpha}X$ I-domain, was found to bind plasminogen, the zymogen of plasmin, with moderate affinity ($1.92{\times}10^{-6}M$) in the presence of $Mg^{2+}$ or $Mn^{2+}$. The ${\beta}D-{\alpha}5$ loop of the ${\alpha}X$ I-domain proved to be responsible for binding, and lysine residues ($Lys^{242}$, $Lys^{243}$) in the loop were the most important for recognizing plasminogen. An excess amount of the lysine analog, 6-aminohexanoic acid, inhibited ${\alpha}X$ I-domain binding to plasminogen, indicating that binding is lysine-dependent. The results of this study indicate that leukocytes regulate plasminogen activation, and consequently plasmin activities, through an interaction with ${\alpha}X{\beta}2$ integrin.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.224-224
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• 2004

Plasminogen activators (PAs)는 자궁분비액, 난포액, 정장물질 등을 포함한 여러 가지 세포외 분비액(extracellular fluids) 및 plasma에 풍부하게 존재하는 세포외 전구효소인 plasminogen을 plasmin으로 전환시키는 단백질분해효소이다. PAs는 섬유소용해, 배란, 착상 및 수정을 포함한 다양한 생리적인 과정에서 중요한 역할을 수행하는 것으로 알려져 있다. 따라서, 본 연구는 돼지의 체외수정 과정시 정자와 난자에서의 plasminogen activators activity의 변화를 SDS-PAGE와 zymography를 이용하여 검토하였다. (중략)

• Reproductive and Developmental Biology
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• v.38 no.2
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• pp.63-70
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• 2014

Plasminogen activators (PAs) are serine proteases that convert plasminogen to plasmin. Two type of PAs are urokinase-type PA (uPA) and tissue-type PA (tPA). Plasminogen is present in most extracellular fluids. PAs play in various reproductive processes including implantation, ovulation and fertilization. In the spermatozoa, PAs and PAIs play a role in sperm motility and fertilization. PAs in the sertoli cell are stimulated spermatozoa maturation and sperm activation through the phospholipase A2. The oocyte maturation is the process for fertilization and implantation. PAs in cumulus-oocyte complexes (COCs) are related to oocyte maturation by protein kinase A and C. In the ovulatory process, PAs activity are changed and it are related to reducing the tensile strength of ovarian follicle wall. The uterine environment is important for reproduction and the uterus undergo tissue remodeling. In the uterus and oviduct of mammals, expression and activity of PAs are changed during estrous cycle. Thus, expression and activity of PAs are concerned to many reproductive functions. Therefore, PAs seem to important factor of regulator in reproductive events.

• The Korean Journal of Zoology
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• v.31 no.3
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• pp.185-190
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• 1988

To investigate whether malignant behavior of skin tumor correlates with changes in the level of proteolytic activities in skin tumors, rats were treated with 7,12-dimethylbenzanthracene followed by photbor ester. Tumors induced upon the treatrnents exhibited more than 20-fold increase in the activity of plasminogen activator and about 3-fold of plasmin-like activity. as compared to those in treated controls. Furthermore, the former activity was raised to about 6-fold even in the preneoplastic dssues of the skin tissues. On the other hand, the proteolytic activity against casein and insulin decreased to several-fold in the tumor tissues while antitrvpsin activity remained similar in both tumor and controls. Thus, the increase in the activities of plasmInogen activator and plasminlike enzyme appears to occur as a charaderistic to skin cancer and may involve in invasion and metsstasis of the tumor.

• Reproductive and Developmental Biology
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• v.32 no.2
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• pp.97-104
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• 2008

Plasminogen activators (PAs) are serine protease that cleave plasminogen to form the active protease plasmin. PA/plasmin system playa role in mammalian fertilization and motility and acrosome reaction of sperm. The present study was undertaken to identify PAs in porcine gametes and investigate a possible role of plasminogen in in vitro fertilization in the pig. When boar spermatozoa were preincubated in a fertilization medium (mTBM) for 0, 2, 4 or 6 h, the activity of tPA-PAI ($110{\sim}117\;kDa$), tPA ($62{\sim}70\;kDa$), and uPA ($34{\sim}38\;kDa$) was observed in the sperm incubation medium and sperm sample. PA activities in the sperm incubation medium significantly (p<0.05) increased according to increasing incubation times, while PA activities in sperm significantly (p<0.05) decreased at the same times. In addition, the rate of acrosome reaction in spermatozoa increased by increasing culture times. When oocytes were separated from porcine cumulus-oocytes complexes at 0, 22 or 44 h of maturation culture, no PA activities were observed in cumulus free-oocyte just after aspiration from follicles. However, the activity of tPA-PAI ($108{\sim}113\;kDa$) and tPA ($75{\sim}83\;kDa$) was observed at 22 h of in vitro culture and significantly (p<0.05) increased as the duration of the culture increased. On the other hand, when porcine oocytes were activated by sperm penetration or calcium ionophore, plasminogen significantly (p<0.05) increased ZP dissolution time (sec) in activated oocytes by sperm penetration. These results suggest that supplementation of plasminogen to fertilization medium may playa positive role in the improvement of in vitro fertilization ability in the pig.

• Journal of Life Science
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• v.20 no.6
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• pp.838-844
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• 2010

A fibrinolytic enzyme of Streptomyces corcohrussi from soil sediment was purified by chromatography using DEAE-Sephadex A-50 and Sephadex G-50. The analysis of SDS-polyacrylamide gel suggested that the purified enzyme is a homogeneous protein and the molecular mass is approximately 34 kDa. The purified enzyme showed activity of 0.8 U/ml in a plasminogen-rich fibrin plate, while its activity in a plasminogen-free fibrin plate was only 0.36 U/ml. These results suggested that the purified enzyme acts as a plasminogen activator. The fibrinolytic activity of the enzyme under the supplementation of protease inhibitors, $\varepsilon$-ACA, t-AMCHA and mercuric chloride in the enzyme reaction was less than 24%, indicating that it could be modulated by the plasmin and/or fibrinogen inhibitors involved in the fibrinogen-to-fibrin converting process. As time passed, $Zn^{2+}$, a heavy metal ion, inhibited the activity to 34.1%. The optimum temperature of the purified enzyme was approximately $50^{\circ}C$ and over 92% of the enzyme activity was maintained between pH 5.0 and 8.0. Therefore, our results provide a potential fibrinolytic enzyme as a noble thrombolytic agent from S. corcohrussi.

• BMB Reports
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• v.47 no.12
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• pp.691-696
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• 2014

${\alpha}$-Enolase is a glycolytic enzyme and a surface receptor for plasminogen. ${\alpha}$-Enolase-bound plasminogen promotes tumor cell invasion and cancer metastasis by activating plasmin and consequently degrading the extracellular matrix degradation. Therefore, ${\alpha}$-enolase and plasminogen are novel targets for cancer therapy. We found that the amino acid sequence of a peptide purified from enzymatic hydrolysates of seahorse has striking similarities to that of ${\alpha}$-enolase. In this study, we report that this peptide competes with cellular ${\alpha}$-enolase for plasminogen binding and suppresses urokinase plasminogen activator (uPA)-mediated activation of plasminogen, which results in decreased invasive migration of HT1080 fibrosarcoma cells. In addition, the peptide treatment decreased the expression levels of uPA compared to that of untreated controls. These results provide new insight into the mechanism by which the seahorse-derived peptide suppresses invasive properties of human cancer cells. Our findings suggest that this peptide could emerge as a potential therapeutic agent for cancer.

• Journal of Embryo Transfer
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• v.25 no.3
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• pp.171-177
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• 2010

Plasminogen activators (PAs) are serine proteases that convert plasminogen to plasmin. The PA/plasmin system has been associated with a number of physiological processes such as fibrinolysis, ovulation and fertilization. Although correlations have been reported between reactive oxygen species (ROS) and oocyte maturation, the relationship between PA activity and ROS is unknown. The present study was undertaken to determine the effects of cumulus cells on PA activity in matured porcine oocytes under xanthine (X)-xanthine oxidase (XO) system. When oocytes were matured under the X-XO system, the proportion of oocytes remaining GV stage was higher (p<0.05) in oocytes without cumulus cells. The incidence of degenerated oocytes was higher (p<0.05) in the X+XO ($11.1{\pm}6.1$ and $21.6{\pm}3.4%$) than in the control group ($2.9{\pm}1.8$ and $4.0{\pm}1.6%$). The proportion of TUNEL-positive oocytes and activity of caspase-3 were higher (p<0.05) in cumulus-free oocytes and oocytes exposed to ROS. Tissue-type plasminogen activator-plasminogen activator inhibitor (tPA-PAI) and tissue-type plasminogen activator (tPA) activity were detected in oocytes that were separated from cumulus-oocytes complexs (COCs) at 44 h of maturation culture, and only tPA was produced in oocytes that were denuded before the onset of maturation culture. On the other hand, the activities of PA were increased (p<0.05) when oocytes were cultured under the X-XO system. The higher activity of tPA was observed in denuded oocytes (DOs) underwent apoptotic changes by oxidative stress. In COCs, however, tPA-PAI as well as tPA activity was detected and apoptotic changes such as DNA cleavage or caspase-3 activation were not observed. These results suggest that tP A may be relevant to apoptotic cell death in porcine oocytes by oxidative stress.