• 생명과학회지
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• 제33권11호
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• pp.859-867
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• 2023

루페올은 5환성 트리테르펜의 일종으로 많은 질병에 치료 효과가 있는 것으로 보고되었으나, 인슐린 저항성에 미치는 영향은 명확하지 않다. 본 연구에서는 3T3-L1 지방세포에서 루페올의 IRS-1 인산화 억제능을 통해 인슐린 저항성 개선효과를 조사하였다. 3T3-L1 세포를 배양하고 TNF-α를 24시간 동안 처리하여 인슐린 저항성을 유도하였다. 서로 다른 농도의 루페올(15, 30 μM) 또는 100 nM의 rosiglitazone을 처리한 세포를 배양한 후, 용해된 세포를 이용하여 western blotting을 시행하였다. 실험결과 루페올은 지방세포에서 TNF-α에 의해 유발되는 인슐린 신호전달의 음성 조절자와 염증 활성화 단백질 kinase에 대한 개선 효과를 나타냈다. 인슐린 신호전달의 음성 조절자인 PTP-1B와 JNK의 활성 및 IKK와 염증활성화 단백질키나아제의 활성을 억제하였다. 또한, 루페올은 IRS-1의 serine 인산화는 하향 조절하고 tyrosine 인산화는 상향 조절하였다. 그 후, 하향 조절된 PI3K/AKT 경로가 활성화되고, GLUT 4의 세포막 전위가 자극되어, 결과적으로 인슐린 저항성이 유도된 3T3-L1 지방세포에서에서 세포내 포도당 흡수가 증가하였다. 본 연구결과, 루페올은 3T3-L1 지방세포에서 인슐린 신호전달 및 염증 활성화 단백질 kinsase들의 음성 조절인자를 억제하여, IRS-1의 serine 인산화를 하향 조절함으로써 TNF-α 유발 인슐린 저항성을 개선할 수 있을 것으로 사료된다.

• 대한수의학회지
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• 제41권3호
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• pp.269-273
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• 2001

The expression of protein kinase C(PKC) isoforms and nitric oxide synthase (NOs) isoforms was studied in the equine vomeronasal organ(VNO), a pheromone receptor organ, using immunohistochemistry. All PKC isoforms including PKC $\alpha$, ${\beta}I$, $\delta$, and $\theta$ were detected in the supporting cells, sensory receptor cells, and basal sensory epithelial cells, while constitutive PKC $\alpha$ and ${\beta}I$ were stained more intensely than novel PKC $\delta$ and ${\theta}$. There was also a varying degree of immunostaining for PKCs in the glandular acini and VNO nerve. Constitutive neuronal and endothelial NOSs, and inducible NOS were detected in the VNO sensory epithelia. There was intense immunoreactivity for endothelial NOS in the VNO sensory epithelia but weak reactivity for neuronal NOS, while inducible NOS showed little immunoreactivity in the adjacent section. These findings suggest that both PKCs and NOSs may be involved in the process of pheromone reception in the horse. Constitutive isoforms of these enzymes may play a more important role in signal trasduction in the VNO of the horse.

• The Korean Journal of Physiology and Pharmacology
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• 제1권1호
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• pp.97-105
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• 1997

The regulatory role of cyclic nucleotides in the expression of neutrophil responses has been examined. fMLP-stimulated superoxide production in neutrophils was inhibited by dibutyryl adenosine 3',5'-cyclic monophosphate (DBcAMP), histamine, adenosine + theophylline, cAMP elevating agents, and 8-bromoguanosine 3' ,5' -cyclic monophosphate (8-BrcGMP) and sodium nitroprusside, cGMP elevating agents. Staurosporine, a protein kinase C inhibitor, genistein, a protein tyrosine kinase inhibitor and chlorpromazine, a calmodulin inhibitor, inhibited superoxide production by fMLP, but they did not further affect the action of DBcAMP on the stimulatory action of fMLP. DBcAMP, histamine, adenosine+theophylline and genistein inhibited myeloperoxidease release evoked by fMLP, whereas BrcGMP, sodium nitroprusside and staurosporine did not affect it. The elevation of $[Ca^{2+}]_i$ evoked by fMLP was inhibited by genistein and chlorpromazine but was not affected by staurosporine. DBcAMP exerted little effect on the initial peak in $[Ca^{2+}]_i$ response to fMLP but effectively inhibited the sustained rise. On the other hand, BrcGMP significantly inhibited both phases. fMLP-induced $Mn^{2+}$ influx was inhibited by either DBcAMP or BrcGMP. These results suggest that fMLP-stimulated neutrophil responses may be regulated by cAMP more than cGMP. cAMP and cGMP appear not affect stimulated responses by direct protein kinase C activation. Their regulatory action on the stimulated neutrophil responses may be not influenced by other activation processes.

• The Korean Journal of Physiology and Pharmacology
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• 제26권2호
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• pp.87-94
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• 2022

Myocardial infarction promotes cardiac remodeling and myocardial fibrosis, thus leading to cardiac dysfunction or heart failure. Peiminine has been regarded as a traditional anti-fibrotic Chinese medicine in pulmonary fibrosis. However, the role of peiminine in myocardial infarction-induced myocardial injury and fibrosis remained elusive. Firstly, rat model of myocardial infarction was established using ligation of the left coronary artery, which were then intraperitoneally injected with 2 or 5 mg/kg peiminine once a day for 4 weeks. Echocardiography and haemodynamic evaluation results showed that peiminine treatment reduced left ventricular end-diastolic pressure, and enhanced maximum rate of increase/decrease of left ventricle pressure (± dP/dt max) and left ventricular systolic pressure, which ameliorate the cardiac function. Secondly, myocardial infarction-induced myocardial injury and infarct size were also attenuated by peiminine. Moreover, peiminine inhibited myocardial infarction-induced increase of interleukin (IL)-1β, IL-6 and tumor necrosis factor-α production, as well as the myocardial cell apoptosis, in the rats. Thirdly, peiminine also decreased the myocardial fibrosis related protein expression including collagen I and collagen III. Lastly, peiminine reduced the expression of p38 and phosphorylation of extracellular signal-regulated kinase 1/2 in rat model of myocardial infarction. In conclusion, peiminine has a cardioprotective effect against myocardial infarction-induced myocardial injury and fibrosis, which can be attributed to the inactivation of mitogen-activated protein kinase pathway.

• 한국발생생물학회지:발생과생식
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• 제3권1호
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• pp.75-85
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• 1999

생쥐 초기 배아의 형태형성에 영향을 주는 세포질내 인자의 기원과 작용기작을 연구하기 위해 단백질 합성과 단백질 활성화 효소 (protein kinase)의 억제제를 처리한 배아의 세포질로 재조합된 배아에서 발생과 RNA합성, 단백질 인산화를 조사하였다. 단백질 합성 억제제인 cycloheximide (CHX)가 함유된 배양액에서 24시간 배양한 1-세포 배아의 제핵된 세포질을 두 개의 전핵을 모두 가진 절반의 1-세포 배아와 재조합한 P+P-CHX군의 배아 발생과 유전자의 활성화는 P+P군의 배아와 유사하였으나, 밀집 형성과 밀집형성이 일어나는 세포 시기는 빨라져서 P+2군과 유사하였다. 또한 초기 배아의 발생 시 1-세포기에서 2-세포기 사이에 일어나는 단백질 인산화가 형태형성과정에 미치는 영향을 알아보기 위해, tyrosine protein kinase와 serine-threonine protein kinase의 억제제인 genistein (Gen)과 6-dimethylaminopurine (6-DMAP)이 처리된 배아의 제핵된 세포질과 2개의 전핵을 가진 절반의 1-세포 배아를 융합시킨 P+2-Gen과 P+2-DMAP군 배아의 발생과 밀집현상을 대조군인 P+P와 P+2군과 비교하였다. P+2-Gen과 P+2-DMAP군 배아에 발생은 대조군에 비해 빨랐으며, 특히 P+2-Gen군 배아는 밀집이 4-세포기에 일어나 8-세포기에 일어나는 P+2-DMAP군의 배아에 비해 일어나는 시간과 세포 시기가 빨라졌다. SDS-PAGE 방법으로 분석한 재조합 3시간째 P+2-Gen과 P+2-DMAP군의 단백질 인산화량은 대조군인 P+P와 P+2군에 비해 증가하였으나 종류의 변화는 없었다. 한편 2차원 전기영동법을 이용하여 P+2-DMAP군의 배아에서 P+2-Gen에 비해 80KD와 110KD 단백질의 인산화가 억제된다는 결과를 얻었다. 이상의 결과들은 생쥐의 초기 배아에서 형태 형성의 조절은 유전자 활성화 또는 난자내 모계 mRNA에 의해 수정 후 합성되는 새로운 단백질에 의한 것이 아니고, 난자내에 존재하는 인자에 의해 조절됨을 시사한다. 이 인자들 중 단백질의 인산화는 배아 발생과 형태형성에 밀접한 관계가 있으며, 특히 초기 1∼2세포기 사이에 serine-threonine protein kinase에 의해 인산화되는 단백질이 밀집현상을 조절하는 데 중요한 역할을 하는 것으로 사료된다.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.75.3-76
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• 2003

The present study was performed to examine mitogen-activated protein kinase associated pathways in mediation of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced cell apoptosis in cultured Jurkat T cells. TCDD significantly decreased cell viability in a concentration-dependent manner (p<0.05 at 10-300 nM). TCDD (10 nM) also time-dependently decreased cell viability (p<0.05 at 12-48 h). c-Jun NH$_2$-terminal kinase was significantly phosphorylated with TCDD treatment in a time dependent manner. (omitted)

• 한국컴퓨터정보학회논문지
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• 제14권3호
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• pp.193-207
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• 2009

세포 내에서 일어나는 단백질 신호 전달 과정은 단백질간의 상호작용을 통해 수행되고 조절된다. Yeast 상호작용 정보와 녹색형광단백질(GFP)을 이용하여 밝혀진 약 5,000여 개의 Yeast 단백질 위치정보를 이용하여 가중치를 부여하고 신호 전달경로 추출 및 예측을 위한 고성능 LocSPF 알고리즘을 최초로 제안하였다. 가중치 알고리즘에 의해 산출된 결과 중 의미 상관도가 높은 것을 채택한 후 KEGG에서 제공하는 신호전달 경로와 같은 신호전달 경로를 추출하는지 유사도 비교를 하였다. 한편 더 나아가 아직 실험을 통해 밝혀지지 않은 단백질 신호전달 경로를 예측하여 결과를 제시함으로써 본 연구를 통해서 알려지지 않은 새로운 신호전달 경로를 발견하거나 이전 경로에 참여하지 않은 단백질들을 발견할 수 있는 가능성을 제시 하였다.

• Animal cells and systems
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• 제2권1호
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• pp.87-91
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• 1998

The present study investigated the involvement of the phospholipase C (PLC) and protein kinase C (PKC) signaling pathways during progesteroneinduced meiotic maturation in amphibian (Rana dybowskii) oocytes. Prosesterone-induced germinal vesicle breakdown (GVBD) of oocytes was significantly inhibited by a PKC inhibitor, staurosporine and a PLC inhibitor, U73122, in a dose-dependent manner. In contrast, U73343, an inactive analogue of U73122, was ineffective in suppressing GVBD. PKC activity in oocytes reached a maximum level at 30 min after progesterone stimulation and this elevated PKC activity was effectively suppressed by U73122 or staurosporine, suggesting that the activation of PKC enzyme is closely linked to PLC signaling during oocyte maturation. In addition, these inhib itors blocked the maturation promoting factor (MPF) activity which appeared in oocytes in response to progesterone, suggesting that PKC activation is an important signal for MPF activity. Therefore, this study demonstrates that the activation of PKC via PLC signaling is directly linked to an intracellular protein kinase cascade related to the appearance of MPF activity during meiotic maturation in amphibian (Rana dybowskii) oocytes.

• IMMUNE NETWORK
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• 제15권4호
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• pp.206-211
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• 2015

Pulmonary edema is a major cause of mortality due to acute lung injury (ALI). The involvement of protein kinase C-${\delta}$ (PKC-${\delta}$) in ALI has been a controversial topic. Here we investigated PKC-${\delta}$ function in ALI using PKC-${\delta}$ knockout (KO) mice and PKC inhibitors. Our results indicated that although the ability to produce proinflammatory mediators in response to LPS injury in PKC-${\delta}$ KO mice was similar to that of control mice, they showed enhanced recruitment of neutrophils to the lung and more severe pulmonary edema. PKC-${\delta}$ inhibition promoted barrier dysfunction in an endothelial cell layer in vitro, and administration of a PKC-${\delta}$-specific inhibitor significantly increased steady state vascular permeability. A neutrophil transmigration assay indicated that the PKC-${\delta}$ inhibition increased neutrophil transmigration through an endothelial monolayer. This suggests that PKC-${\delta}$ inhibition induces structural changes in endothelial cells, allowing extravasation of proteins and neutrophils.

• Genomics & Informatics
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• 제7권4호
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• pp.181-186
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• 2009

Myotonic dystrophy type 1 (DM1), which is a dominantly inherited neurodegenerative disorder, results from a CTG trinucleotide repeat expansion in the 3'-untranslated region (3'-UTR) of the myotonic dystrophy protein kinase (DMPK) gene. Retention of mutant DMPK (mDMPK) transcripts in the nuclei of affected cells has been known to be the main cause of pathogenesis of the disease. Thus, reducing the RNA toxicity through elimination of the mutant RNA has been suggested as one therapeutic strategy against DM1. In this study, we suggested RNA replacement with a trans -splicing ribozyme as an alternate genetic therapeutic approach for amelioration of DM1. To this end, we identified the regions of mDMPK 3'-UTR RNA that were accessible to ribozymes by using an RNA mapping strategy based on a trans-splicing ribozyme library. We found that particularly accessible sites were present not only upstream but also downstream of the expanded repeat sequence. Repair or replacement of the mDMPK transcript with the specific ribozyme will be useful for DM1 treatment through reduction of toxic mutant transcripts and simultaneously restore wild-type DMPK or release nucleus-entrapped mDMPK transcripts to the cytoplasm.