• Journal of Life Science
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• v.19 no.2
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• pp.157-162
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• 2009

Nitric oxide (NO) is a diffusible, multifunctional and transcellular messenger that has been implicated in numerous physiological and pathological conditions. It has been reported that NO induced apoptosis in tumor cells, macrophage cells and inhibited apoptosis in normal cells, endothelial cells. To examine whether NO could induce apoptosis in MCF-7 cells, cells were treated with SIN-1 (3-morpholinosydnonimine), NO donor. Cell viability did not change in SIN-1 treated cells for 48 h and there was no significantly changes in cell cycle progression or growth pattern by FACS analysis. But p53 protein, an apoptosis-related factor, increased SIN-1 treatment time dependently. Bcl-2, MDM2 and p21 were also accumulated. Bax level did not change. A major role of inhibiting apoptosis by NO in MCF-7 cells, cobalt chloride ($CoCl_2$) was added to cells preincubated with SIN-1. Whereas $CoCl_2$ treated cells underwent apoptosis, for 24 h SIN-1 preincubated cells were not induced apoptosis. Inactivated proteins, MDM2 and bcl-2, by $CoCl_2$ levels also increased in SIN-1 pre-treated cells. These results suggested that SIN-1 blocked p53 by MDM2 activation and inhibited apoptosis by inducing p21 and bcl-2 expression.

• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.213-219
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• 2011

The metastatic effect of Eupatorium japonicum extract (EJE) on MDA-MB-231 human breast cancer cells was investigated. MDA-MB-231 cells were treated with various concentrations of EJE (0, 5, 10 and $20{\mu}g/mL$). EJE inhibited cell migration, invasion and adhesion of MDA-MB-231 cells in dose-dependent manners. Gelatin zymography exhibited that EJE significantly down regulated secretion of matrix metalloproteinase (MMP)-9 and MMP-2. EJE decreased the protein levels of tissue inhibitor of metalloproteinase (TIMP)-1 but increased TIMP-2 levels. Additionally, EJE reduced the protein and mRNA levels of urokinase-type plasminogen activator (uPA), vascular endothelial growth factor (VEGF) and intercellular adhesion molecule (ICAM). In several solvent fractions of EJE, the hexane fraction markedly decreased MDAMB-231 cell migration. Thus, these finding suggest that EJE may be a potential antimetastatic agent, which can considerably inhibit the metastatic and invasive capacity of breast cancer cells.

• The Korean Journal of Physiology and Pharmacology
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• v.14 no.1
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• pp.37-43
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• 2010

The serine/threonine kinase Akt has been shown to play a role of multiple cellular signaling pathways and act as a transducer of many functions initiated by growth factor receptors that activate phosphatidylinositol 3-kinase (PI3K). It has been reported that phosphorylated Akt activates eNDS resulting in the production of NO and that NO stimulates soluble guanylate cyclase (sGC), which results in accumulation of cGMP and subsequent activation of the protein kinase G (PKG). It has been also reported that PKG activates PI3K/Akt signaling. Therefore, it is possible that PI3K, Akt, eNOS, sGC, and PKG form a loop to exert enhanced and sustained activation of Akt. However, the existence of this loop in eNOS-expressing cells, such as endothelial cells or astrocytes, has not been reported. Thus, we examined a possibility that Akt phosphorylation might be enhanced via eNOS/sGC/PKG/PI3K pathway in astrocytes in vivo and in vitro. Phosphorylation of Akt was detected in astrocytes after KA treatment and was maintained up to 72 h in mouse hippocampus. 2 weeks after KA treatment, astrocytic Akt phosphorylation was normalized to control. The inhibition of eNOS, sGC, and PKG significantly decreased Akt and eNDS phosphorylation induced by KA in astrocytes. In contrast, the decreased phosphorylation of Akt and eNDS by eNDS inhibition was significantly reversed with PKG activation. The above findings in mouse hippocampus were also observed in primary astrocytes. These data suggest that Akt/eNOS/sGC/PKG/PI3K pathway may constitute a loop, resulting in enhanced and sustained Akt activation in astrocytes.

• Journal of Nutrition and Health
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• v.53 no.2
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• pp.111-120
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• 2020

Purpose: Corosolic acid (CA), also known as 2α-hydroxyursolic acid, is present in numerous plants, and is reported to exhibit anti-cancer and anti-proliferative activities in various cancer cells such as osteosarcoma, hepatocellular carcinoma, lung adenocarcinoma, and colon cancer. However, the anti-cancer activity of CA on human breast cancer cells and the underlying mechanisms remain to be elucidated. The present study aimed to investigate the anticancer effects of CA in the human breast cancer cell line, MDA-MB-231. Methods: Cell viability, reactive oxygen species (ROS) production, apoptosis marker protein expression, migration, invasion rate, and vascular endothelial growth factor (VEGF) levels were assessed by treating MDA-MB-231 cells to increasing concentrations of CA. Results: The results showed that CA significantly inhibited the cell proliferation of MDA-MB-231 cells in a dose-dependent manner. To assess the effect of CA on apoptosis, nuclei of MDA-MB-231 cells were stained with DAPI solution. Chromatin condensation, which indicates apoptosis, was observed to increase dose-dependently. In addition, western-blot analysis revealed elevated levels of the apoptosis marker proteins (Bax and cleaved caspase 3) subsequent to MDA-MB-231 exposure to CA. ROS production was also increased in the CA-induced apoptosis in MDA-MB-231 treated cells. Interestingly, CA exposure resulted in significantly decreased migration and invasion rates in the MDA-MB-231 cells. Data further revealed that exposure to CA markedly decreased the VEGF concentration, thereby contributing to a reduction in angiogenesis. Conclusion: Our results determined that exposure to CA induces anti-proliferation, apoptosis, and ROS production, and suppresses cell migration and invasion rate in MDA-MB-231 cells. Taken together, these results indicate the potential of CA to be applied as an effective chemotherapeutic agent for treating breast cancer.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.6
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• pp.771-781
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• 2013

This study was performed to investigate the anti-photoaging effects of Persimmon leaf tea(PLT) in hairless mice(SKH-1) exposed to UVB irradiation. The animals were divided into non-treated group (normal, N) and UV-radiated groups. UV-radiated groups were divided into only UV-radiated group(control, C) and UV-radiated and PLT treated experimental groups[first extraction treated group(PLT-I), second extraction treated group(PLT-II), and third extraction treated group(PLT-III)]. Three PLT treated experimental groups of mice were treated with both oral administration(300 mg/Kg B.W./day) and topical application (100 ul of 2% conc./mouse/day) for 4 weeks. Anti-photoaging effects of Persimmon leaf were evaluated by anti oxidative reaction, stereomicroscopic and microscopic observations. The expression of photoaging skin related factors including mast cell tryptase, proliferating cell nuclear antigen (PCNA) and vascular endothelial growth factor (VEGF) was examined by immunohistochemical staining. Treatment of PLT-I, -II, -III prevented the wrinkle formation as well as epidermal hyperplasia, inflammatory cells, disruption of collagen in photoaged skin induced by UVB radiation. It also reduced the PCNA and VEGF expression in the UVB irradiated dorsal skin. Furthermore, it significantly decreased the number of mast cells in the UVB irradiated dermis(p<0.05 and p<0.01). On the effects of oxidative stress and antioxidant function on the treatment with water extract from Persimmon leaf tea(PLT), the activity of superoxide dismutase(SOD) was significantly increased in PLT-III group(p<0.05), and catalase(CAT) was significantly increased in PLT-I and PLT-III groups(p<0.05), and PLT-II group(p<0.001). These extracts showed relatively antioxidant activity and protective effect on UVB-induced oxidative stress in hairless mice(SKH-1). Our results suggest that Persimmon leaf tea may serve as an useful radical scavenging antioxidant and anti-photoaging skin agents in the UVB irradiated skin.

• Journal of Yeungnam Medical Science
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• v.13 no.2
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• pp.159-172
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• 1996

대기오염물질이면서 동시에 생체내 화학반응의 산물이기도 한 nitric oxide(NO)는 그 생체내 분포가 광범위하고 생리적 역할이 다양하여, 최근의 생명과학 분야에서 가장 크게 주목받는 몇가지 연구대상 중 하나이다. 세포에서의 NO 산생은 nitric oxide synthase (NOS)에 의해 촉매되는데, 이들은 brain form (bNOS, neuronal; nNOS, NOS I), inducible form (iNOS), 및 endothelial form(eNOS)로 구분되는데, 이중 bNOS(nNOS)와 eNOS는 inducible form에 대비되는 constitutive form(cNOS)에 해당하므로 각각 ncNOS 와 ecNOS로도 불리운다. NOS는 아미노산인 L-arginine을 산소와 결합시켜 L-citrulline으로 변환시키면서 NO를 유리하고, 이 NO는 세포내의 guanylate cyclase를 활성화하여 cyclic GMP를 생산하거나, superoxide(O2-) 및 수소이온과 차례로 결합하여 반응성이 매우 높은 수산화기(-OH)를 발생시켜 세포독작용을 유발하기도 한다. 정상상태에서 뇌혈관내피세포의 ecNOS로 부터 유리된 NO는 혈관을 확장시켜 신경세포에 대한 산소공급을 원활히 유지해 주지만, 순환장애를 일으켰을 때는 뇌조직내의 iNOS로부터 대량의 NO가 유출되어 신경세포의 손상을 가져온다. 호흡기에서는 NO가 기도평활근을 이완시키고 폐혈류를 개선하므로, 미숙아나 성인의 호흡장애시에 소량의 NO를 흡입시키면 oxygenation을 호전시킬 수 있다. 그러나 대기오염이나 흡연 등으로 대량의 NO를 흡입할 경우 치명적인 폐부종이나 methemoglobin혈종을 일으킬 수 있다. 순환계에서는 cNOS가 혈관을 확장시켜 조직의 혈류를 유지하는데 일익을 담당한다. 세균내 독소(lipopolysaccharide; LPS)나 각종 명역조절물질들이 혈관내피세포와 혈관평활근세포로 부터 과다한 NO를 유리시키면 혈압이 급격히 떨어져 순환허탈상태에 빠지게 된다. 심장에서는 관상혈관 내피세포의 eNOS가 심근의 혈류를 유지해 주지만 허혈이나 세균내독소 또는 면역조절물질 등에 의하여 심근세포나 침윤된 대식세포의 iNOS로 부터 과량의 NO가 유리되면 심근세포의 손상이 초래된다. 신장에서는 내피세포의 cNOS에 의하여 사구체여과가 조절되고 있는데, 세균내독소나 면역 조절물질 등에 의하여 사구체관막세포(mesangial cell)등의 iNOS로 부터 과량의 NO가 유리되면 신조직과 사구체의 손상을 초래한다. 위와 같이 대부분의 장기에서 ecNOS는 조직의 혈류를 유지하는 역할을 하며, iNOS는 애초 세균 등 침입자에 대한 세포독작용이 그 존재 목적이라고 풀이할 수 있겠으나 일종의 부작용으로 자체조직의 손상을 초래하게 되는 것으로 본다. 따라서 NO와 관련된 각종 병변의 치료를 위해서는 NOS의 비선택성 억제제인 arginine 유도체 보다는 iNOS에 대한 선택적 억제제인 S-methylisothiourea(SMT), aminoethylisothiourea(AETU), aminoguanidine (AMG), agmatine, L-canavanine, transforming growth factor b1(TGF-b1) 등의 사용을 검토해 보는 것이 타당할 것으로 사료된다.

• Journal of Korean Neurosurgical Society
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• v.50 no.4
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• pp.281-287
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• 2011

Objective : Pituitary apoplexy is life-threatening clinical syndrome caused by the rapid enlargement of a pituitary tumor due to hemorrhage and/or infarction. The pathogenesis of pituitary apoplexy is not completely understood. We analyzed the magnetic resonance imaging (MRI) of pituitary tumors and subsequently correlated the radiological findings with the clinical presentation. Additionally, immunohistochemistry was also performed to determine whether certain biomarkers are related to radiological apoplexy. Methods : Thirty-four cases of pituitary adenoma were enrolled for retrospective analysis. In this study, the radiological apoplexy was defined as cases where hemorrhage, infarction or cysts were identified on MRI. Acute clinical presentation was defined as the presence of any of the following symptoms: severe sudden onset headache, decreased visual acuity and/or visual field deficit, and acute mental status changes. Angiogenesis was quantified by immunohistochemical expression of fetal liver kinase 1 (Flk-1), neuropilin (NRP) and vascular endothelial growth factor (VEGF) expression, while microvascular density (MVD) was assessed using Endoglin and CD31. Results : Clinically, fourteen patients presented with acute symptoms and 20 for mild or none clinical symptoms. Radiologically, fifteen patients met the criteria for radiological apoplexy. Of the fifteen patients with radiologic apoplexy, 9 patients presented acute symptoms whereas of the 19 patient without radiologic apoplexy, 5 patients presented acute symptoms. Of the five biomarkers tracked, only VEGF was found to be positively correlated with both radiological and nonradiological apoplexy. Conclusion : While pituitary apoplexy is currently defined in cases where clinical symptoms can be histologically confirmed, we contend that cases of radiologically identified pituitary hemorrhages that present with mild or no symptoms should be designated subacute or subclinical apoplexy. VEGF is believed to have a positive correlation with pituitary hemorrhage. Considering the high rate of symptomatic or asymptomatic pituitary tumor hemorrhage, additional studies are needed to detect predictors of the pituitary hemorrhage.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.6
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• pp.453-460
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• 2009

Background and Purpose: Vascular endothelial growth factor (VEGF)-C, VEGF-D and their tyrosine kinase receptor, VEGF receptor (VEGFR)-3 are recently known to have lymphangiogenic activities in various tumor types. Oral mucosal squamous cell carcinoma (OMSCC) easily metastasizes to cervical lymph nodes, so we determined the expression levels of VEGF-C, VEGF-D and VEGFR-3 in oral squamous cell carcinoma. Materials and Methods: We performed Western blot analyses with 4 OMSCC cultured tumor cell lines (SCC9, KB, YD-10B, YD-38), and with 7 surgical specimens of OMSCC for the detection of VEGF-C, VEGF-D and VEGFR-3 proteins. Expression of VEGF-C mRNA as well as mRNA for VEGFR-3 in 4 OMSCC cell lines (KB, SCC-4, SCC-9, YD-10B) was investigated by RT-PCR. We also measured VEGFC/VEGF-D protein concentrations in the media and protein concentration of VEGFR-3 in cell lysates of 4 OMSCC cell lines (SCC9, KB, YD-10B, YD-38) using commerical ELISA kits. Finally, we performed immunoprecipitation for the detection of VEGF-C in cell lysates of 4 OMSCC cells (KB, SCC-4, SCC-9, YD-10B) and real-time RT-PCR for the quantification of VEGF-C mRNA. Results: In the result of Western blotting with cell lysates of 4 OMSCC cells, we could not detect the protein expression of VEGF-C, VEGF-D, and VEGFR-3. But, all tumor tissues demonstrated VEGF-C and VEGFR-3. VEGF-C mRNA was detected at various levels in 4 OMSCC cell lines. Moreover, OMSCC cells secreted VEGF-C, not VEGF-D and VEGFR-3 was also detected in cell lysates of OMSCC by ELISA. Immunoprecipitation and real-time RT-PCR revealed VEGF-C was also expressed in 4 OMSCC cell lines. Conclusion: Taken together, tumor cells of OMSCC secrete VEGF-C, not VEGF-D. And VEGFR-3 is expressed tumor cells as well as OMSCC tumor tissues, needs further study.

• Molecules and Cells
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• v.40 no.6
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• pp.386-392
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• 2017

Periodontal ligament stem cells (PDLSCs) are multipotent stem cells derived from periodontium and have mesenchymal stem cell (MSC)-like characteristics. Recently, the perivascular region was recognized as the developmental origin of MSCs, which suggests the in vivo angiogenic potential of PDLSCs. In this study, we investigated whether PDLSCs could be a potential source of perivascular cells, which could contribute to in vivo angiogenesis. PDLSCs exhibited typical MSC-like characteristics such as the expression pattern of surface markers (CD29, CD44, CD73, and CD105) and differentiation potentials (osteogenic and adipogenic differentiation). Moreover, PDLSCs expressed perivascular cell markers such as NG2, ${\alpha}-smooth$ muscle actin, platelet-derived growth factor receptor ${\beta}$, and CD146. We conducted an in vivo Matrigel plug assay to confirm the in vivo angiogenic potential of PDLSCs. We could not observe significant vessel-like structures with PDLSCs alone or human umbilical vein endothelial cells (HUVECs) alone at day 7 after injection. However, when PDLSCs and HUVECs were co-injected, there were vessel-like structures containing red blood cells in the lumens, which suggested that anastomosis occurred between newly formed vessels and host circulatory system. To block the $SDF-1{\alpha}$ and CXCR4 axis between PDLSCs and HUVECs, AMD3100, a CXCR4 antagonist, was added into the Matrigel plug. After day 3 and day 7 after injection, there were no significant vessel-like structures. In conclusion, we demonstrated the perivascular characteristics of PDLSCs and their contribution to in vivo angiogenesis, which might imply potential application of PDLSCs into the neovascularization of tissue engineering and vascular diseases.

• Journal of Chest Surgery
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• v.33 no.6
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• pp.494-501
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• 2000

Background: Transmyocardial laser revascularization(TMLR) for revascularizing ischemic myocardium in patients was originally based on the assumption that laser channels remain their patency much longer. But recent studies show that laser channels did not remain open and that TMLR could achieve treatment benefits without long-term channel patency. The angiongencesis is currently thought to be induced by non-specific inflammatory response to mechanical tissue injury. This study is to evaluate hypothesis that various transmyocaridal mechanical revascularization(TMMR) may induce the angiogenic responses similar to that seen with TMLR, and transmyocaridal polymer stent revascularization(TMSR), the polymer stent in the myocardial tissue is hydrolyzed in 2 weeks, may enhance the non-specific inflammatory reaction resulting angiogenesis. Furthermore, polymer myocaridal stent channels remain long-term patency. Material and Method: Eight domestic pigs underwent ligation of the proximal circumflex artery, and 2 weeks later they were randomized to undergo transmycardial acupunctural revascularization (TMPR, Group I) of the left lateral wall with 18-G needle(n=2), to undergo transmyocardial (TMDR, Group II) with industrial 2mm steel drill(n=2), to undergo transmyocardial polymer stent revascularization (TMSR, Group III) after drilling the infarcted myocardium(n=2), the stent is poly(lactic acid-co-glycolic acid), which is self-degradated in the myocardium, and to a control group the ischemic zone was unterated(n=2). All the pigs were sacrificed after 4 weeks TMMR. Sections from the ischemic zone were submitted for vascular endothelial growth factor (VEGF) ELISA and histology. Result: There were makedly increase in the VEGF immunoassay in the ischemic zone of the TMMR group compared to the ischemic zone of the control group(control: each 30.85 and 43.15pg/mg protein, TMPR: each 44.14 and 68.61 pg/mg protein, TMDR: each 65.92 and 78.65 pg/mg protein, TMSR: each 177.39 and 168.87 pg/mg protein). TMSR channels caused greatest VEGF expression than channels made by other group and the polymer stent channels remained vacuole after 4 weeks. Conclusion: Transmyocardial polymer stent revascularization promoted the most angiogenci response by the VEGF immunoassay, although our study did not show the statistical significancy. The channels remained but the flow patency was not verified. Transmyocardial polymer stent revascularization (TMSR) is desirable in future experimental trials and in view of the significant cost implications comparable to that of laser.