• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.82-83
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• 2003

Plants have evolved differently from animals having mobile activities. Thus, plants should have developed unique defense mechanisms against biotic/abiotic stresses to which plants are differently exposed, according to seasons. Most organisms have an conserved signaling network using mitogen-activated protein kinase (MAPK) cascade(s). The phenomenon implied that they are functionally very important in all organisms. In fact, they constitute one of the major components of signaling pathways involved in regulating a wide range of cellular activities from growth and development to cell death. Recently, complete MAPK cascade was first characterized in Arabidopsis from the receptor kinase (FLS2) through fellowing MEKKI -MKK4/MKK5-MPK3/MPK6-WRKY22/MRKY29 pathway. Whereas, MAPK cascade signaling pathway in monocot plant including rice (0ryza sativa L.), the most important of all food crops and an established monocot plant research model, MAPKinase kinase kinases (MAPKKK) of rice are the first upstream component of the MAPK cascade, but MAPKKK has been first identified and characterized in our lab and designated as, OsEDRl based on its homology with the Arabidopsis EDRI. The Arabidopsis EDRl was regarded as a negative regulator of defense response and the role of rice OsEDRl was analyzed. Transcriptional regulation of OsEDRl was detected under various stresses and immunoblotting analysis is going on to detect the level of OsEDRl protein in the mutants showing unique phenotype. We also introduced the constitutively active and the dominant negative forms of the OsEDRl for characterizing biological function.

• 한방비만학회지
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• 제24권1호
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• pp.25-40
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• 2024

Objectives: In the present study, we investigated the effects of clean-diabetes mellitus 3 (C-DM3), a herbal formula with Trichosanthis Radix, Coptidis Rhizoma, Crataegi Fructus, and Cinnamomi Cortex, on the pathological and serological symptoms of diabetes and its related molecular mechanisms in diet-induced obese mice. Methods: We prepared an obese mouse model using a high-fat diet for 8 weeks and then administered the C-DM3 extract for 4 weeks. The changes of pathological and serological biomarkers for diabetes assessment were measured in the mice and histological changes were observed in the liver and pancreas tissues. We also identified the main compounds in the C-DM3 extract using high pressure liquid chromatography (HPLC) and analyzed the molecular mechanism of the disease condition by network pharmacological analysis. Results: In the in vivo, the administration of C-DM extract to obese mice significantly reduced body weight gain, fatty liver symptoms, and muscle loss, and decreased the levels of fasting blood glucose, insulin, aspertate aminotransferase, triglycerides, and low-density lipoprotein-cholesterol. In addition, C-DM extract significantly increased the phosphorylation of insulin receptor substrate 1, protein kinase b (AKT), phosphoinositide 3-kinase (PI3K), adenosine monophosphate-activated protein kinase, and glucose transporter 4 in all pancreatic and liver tissues, with inhibition of histopathological changes in obese mice. HPLC analysis identified hyperoside, berberine, epiberberine, columbamin, coptisine, coumarin, jatrorrhizine, and citric acid as the main compounds. In the network pharmacological analysis, the molecular targets of C-DM3 extract on obesity and diabetes were shown as the insulin, AKT, PI3K, and mitogen-activated protein kinase pathways with the regulation of inflammatory molecules interleukin 6 (IL-6), jun proto-oncogene, and IL-1β, which matched our in vivo targets. Conclusions: Based on these results, C-DM3 extract is expected to be effective in improving obesity and preventing diabetic progression.

• 한국해양생명과학회지
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• 제6권2호
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• pp.58-65
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• 2021

노화가 진행될수록 활성산소종으로 인하여 피부 보습은 떨어지고 피부 장벽은 붕괴되어 피부가 손상된다. 본 연구에서는 인천 동막 해변에 서식하는 염생식물인 갯끈풀(Spartina anglica; SAE)과 갯메꽃(Calystegia soldanella; CSE)을 70% 에탄올(EtOH)로 추출하여 피부 보습 및 피부 장벽 기능 강화에 대한 효능을 평가하였다. 이 추출물들에 대한 피부 각질형성세포(HaCaT cell)에서 세포독성을 WST-8 assay를 이용하여, 세포 생존율이 90% 이상을 보이는 농도를 선별하여 추가 실험을 진행하였다. ABTS 라디칼 소거능을 통해 항산화 효과를 확인한 결과, SAE와 CSE는 높은 라디칼 소거능을 보였다. 피부 보습과 관련된 인자들인 filaggrin (FGL), aquaporin 3(AQP3), hyaluronan synthase 2 (HAS2)과 피부 장벽 기능과 연관 있는 transglutaminase 1 (TGM1)과 involucrin (INV)의 유전자 수준에서의 발현 변화를 측정한 결과, SAE에 의해 AQP3, HAS2, TGM1의 발현이 증가하였으나, CSE는 변화가 없는 것을 확인할 수 있었다. SAE에 의한 세포 내 신호전달 경로를 확인하기 위해 western blot 분석을 수행하였다. Extracellular signal regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 mitogen activated protein kinase의 활성이 SAE에 의하여 상향 조절되었음을 확인하였다. 이러한 결과는 갯끈풀 추출물이 피부 보습 및 피부 장벽 기능 강화를 위한 화장품의 기능성 소재로 사용될 수 있음을 시사한다.

• The Korean Journal of Physiology and Pharmacology
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• 제20권1호
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• pp.9-14
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• 2016

Adenosine 3',5'-cyclic monophosphate (cAMP) participates in the regulation of numerous cellular functions, including the $Na^+-K^+$-ATPase (sodium pump). Ouabain, used in the treatment of several heart diseases, is known to increase cAMP levels but its effects on the atrium are not understood. The aim of the present study was to examine the effect of ouabain on the regulation of atrial cAMP production and its roles in atrial endothelin-1 (ET-1) secretion in isolated perfused beating rabbit atria. Our results showed that ouabain ($3.0{\mu}mol/L$) significantly increased atrial dynamics and cAMP levels during recovery period. The ouabain-increased atrial dynamics was blocked by KB-R7943 ($3.0{\mu}mol/L$), an inhibitor for reverse mode of $Na^+-Ca^{2+}$ exchangers (NCX), but did not by L-type $Ca^{2+}$ channel blocker nifedipine ($1.0{\mu}mol/L$) or protein kinase A (PKA) selective inhibitor H-89 ($3.0{\mu}mol/L$). Ouabain also enhanced atrial intracellular cAMP production in response to forskolin and theophyline ($100.0{\mu}mol/L$), an inhibitor of phosphodiesterase, potentiated the ouabain-induced increase in cAMP. Ouabain and 8-Bromo-cAMP ($0.5{\mu}mol/L$) markedly increased atrial ET-1 secretion, which was blocked by H-89 and by PD98059 ($30{\mu}mol/L$), an inhibitor of extracellular-signal-regulated kinase (ERK) without changing ouabain-induced atrial dynamics. Our results demonstrated that ouabain increases atrial cAMP levels and promotes atrial ET-1 secretion via the mitogen-activated protein kinase (MAPK)/ERK signaling pathway. These findings may explain the development of cardiac hypertrophy in response to digitalis-like compounds.

• 환경생물
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• 제21권1호
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• pp.52-55
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• 2003

There is considerable evidence that ionizing radiation (IR) mediates checkpoint control, repair and cell death. In this study, we have used a high density microarray hybridization approach to characterize the transcriptional response of human breast carcinoma MCF-7 cell line to ${\gamma}$-radiation, such as 4 Gy 4 hr, 8 Gy 4 hr, and 8 Gy 12 hr. We found that exposure to ${\gamma}$-ray alters by at least a $log_2$ factor of 1.0 the expression of 115 known genes. Of the 66 genes affected by ${\gamma}$-radiation, 49 are down-regulated. In our results, the cellular response to irradiation includes induction of the c-jun and EGR1 early response genes. The present work has examined potential cytoplasmic signaling cascades that transduce IR-induced signals to the nucleus. 40S ribosomal protein s6 kinase modulates the activities of the mitogen activated protein kinase (MAPK) and c-Jun $NH_2$-terminal kinase (JNK1) cascades in human monocytic leukemia (U937/pREP4) cells. 14-3-3 family members are dimeric phosphoserine -binding proteins that participate in signal transduction and checkpoint control pathways.

• International Journal of Oral Biology
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• 제44권2호
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• pp.43-49
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• 2019

Tannic acid (TA) is a water-soluble polyphenol compound found in various herbal plants. We investigated the chemopreventive effects of TA on FaDu hypopharyngeal squamous carcinoma cells. In an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, TA showed dose-dependent cytotoxicity with a half maximal inhibitory concentration (IC50) of 50 ?M. Cell cycle analysis and immunofluorescence imaging demonstrated that under low-dose ($25{\mu}M$) treatment, FaDu cells were arrested in G2/M phase, and as the dose of TA was increased, apoptosis was induced with the increase of cell population at sub-G1 phase. The expressions of various cyclins, including cyclin D1 and cyclin-dependent kinases (CDK-1 and CDK-2), were down-regulated at low doses of TA, whereas apoptotic effectors such as cleaved caspase 3, cleaved caspase 7, and poly (ADP-ribose) polymerase (PARP) were expressed in a dose-dependent manner in Western blotting. In addition, TA-induced apoptosis of FaDu cells might be mediated by the extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase pathway, with the upregulation of p-AKT/p-PKB (phosphorylated protein kinase B) and p-ERK. Overall, our data support the hypothesis that TA is a potential candidate agent for the treatment of hypopharyngeal cancer.

• BMB Reports
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• 제46권4호
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• pp.213-218
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• 2013

Members of the colony stimulating factor cytokine family play important roles in macrophage activation and recruitment to inflammatory lesions. Among them, granulocyte-macrophage colony stimulating factor (GM-CSF) is known to be associated with immune response to mycobacterial infection. However, the mechanism through which Mycobacterium tuberculosis (MTB) affects the expression of GM-CSF is poorly understood. Using PMA-differentiated THP-1 cells, we found that MTB infection increased GM-CSF mRNA expression in a dose-dependent manner. Induction of GM-CSF mRNA expression peaked 6 h after infection, declining gradually thereafter and returning to its basal levels at 72 h. Secretion of GM-CSF protein was also elevated by MTB infection. The increase in mRNA expression and protein secretion of GM-CSF caused by MTB was inhibited in cells treated with inhibitors of p38 MAPK, mitogen-activated protein kinase kinase (MEK-1), and PI3-K. These results suggest that up-regulation of GM-CSF by MTB is mediated via the PI3-K/MEK1/p38 MAPK-associated signaling pathway.

• Natural Product Sciences
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• 제17권4호
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• pp.273-278
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• 2011

In this study, the effects of a methanol (MeOH) extract of Carduus crispus L. (Asteraceae) on adipogenesis was investigated in 3T3-L1 cells. To differentiate preadipocytes to adipocytes, confluent 3T3-L1 preadipocytes were treated with a hormone mixture, which included isobutylmethylxanthine, dexamethasone, and insulin (MDI). The methanol extract of C. crispus significantly decreased fat accumulation by inhibiting adipogenic signal transcriptional factors in MDI-induced 3T3-L1 cells in a dose-dependent manner. In MTT assays and on PI-staining, methanol extract of C. crispus inhibited the proliferation of 3T3-L1 cells during mitotic clonal expansion (MCE). The anti-adipogenic effect of the Carduus extract seemed to be associated with the upregulation of extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (MAPK) pathways within the first 2 days after MDI treatment. These results suggest that methanol extract of C. crispus might be beneficial for the treatment of obesity.

• The Korean Journal of Physiology and Pharmacology
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• 제13권4호
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• pp.281-285
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• 2009

Rotenone, a mitochondrial complex I inhibitor, can induce the pathological features of Parkinson's disease (PD). In the present study, naringin, a grapefruit flavonoid, inhibited rotenone-induced cell death in human neuroblastoma SH-SY5Y cells. We assessed cell death and apoptosis by measuring mitogen-activated protein kinase (MAPKs) and caspase (CASPs) activities and by performing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, 4,6-diamidino-2-phenylindole (DAPI) staining, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. Naringin also blocked rotenone-induced phosphorylation of Jun NH2-terminal protein kinase (JNK) and P38, and prevented changes in B-cell CLL/lymphoma 2 (BCL2) and BCL2-associated X protein (BAX) expression levels. In addition, naringin reduced the enzyme activity of caspase 3 and cleavages of caspase 9, poly (ADP-ribose) polymerase (PARP), and caspase 3. These results suggest that naringin has a neuroprotective effect on rotenone-induced cell death in human neuroblastoma SH-SY5Y cells.

• The Korean Journal of Physiology and Pharmacology
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• 제15권1호
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• pp.1-7
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• 2011

Many anticancer agents as well as ionizing radiation have been shown to induce autophagy which is originally described as a protein recycling process and recently reported to play a crucial role in various disorders. In HCT116 human colon cancer cells, we found that curcumin, a polyphenolic phytochemical extracted from the plant Curcuma longa, markedly induced the conversion of microtubule-associated protein 1 light chain 3 (LC3)-I to LC3-II and degradation of sequestome-1 (SQSTM1) which is a marker of autophagosome degradation. Moreover, we found that curcumin caused GFP-LC3 formation puncta, a marker of autophagosome, and decrease of GFP-LC3 and SQSTM1 protein level in GFP-LC3 expressing HCT116 cells. It was further confirmed that treatment of cells with hydrogen peroxide induced increase of LC3 conversion and decrease of GFP-LC3 and SQSTM1 levels, but these changes by curcumin were almost completely blocked in the presence of antioxidant, N-acetylcystein (NAC), indicating that curcumin leads to reactive oxygen species (ROS) production, which results in autophagosome development and autolysosomal degradation. In parallel with NAC, SQSTM1 degradation was also diminished by bafilomycin A, a potent inhibitor of autophagosome-lysosome fusion, and cell viability assay was further confirmed that cucurmin-induced cell death was partially blocked by bafilomycin A as well as NAC. We also observed that NAC abolished curcumin-induced activation of extracelluar signal-regulated kinases (ERK) 112 and p38 mitogen-activated protein kinases (MAPK), but not Jun N-terminal kinase (JNK). However, the activation of ERK1/2 and p38 MAPK seemed to have no effect on the curcumin-induced autophagy, since both the conversion of LC3 protein and SQSTM1 degradation by curcumin was not changed in the presence of NAC. Taken together, our data suggest that curcumin induced ROS production, which resulted in autophagic activation and concomitant cell death in HCT116 human colon cancer cell. However, ROS-dependent activation of ERK1/2 and p38 MAPK, but not JNK, might not be involved in the curcumin-induced autophagy.