• 대한의생명과학회지
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• 제18권2호
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• pp.165-168
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• 2012

Hox proteins containing DNA-binding homedomain act as transcription factors important for anteroposterior body patterning during vertebrate embryogenesis. However, the precise mechanisms by which signal pathways are transduced to regulate the Hox gene expression are not clear. In the course of an attempt to isolate an upstream regulatory factor(s) controlling Hox genes, protein kinase B alpha (Akt1) has been identified as a putative regulator of Hox genes through in silico analysis (GEO profile). In the Gene Expression Omnibus (GEO) dataset GDS1784 at the NCBI (National Center for Biotechnology Information) site, Hox genes were differentially expressed depending on the presence or absence of Akt1. Since it was not well known how Akt1 regulates the specific Hox genes, whose transcription was reported to be regulated by epigenetic modifications such as histone acetylation, methylation etc., the expression of Gcn5, a histone acetyltransferase (HAT), was analyzed in wild type (WT) as well as in $Akt1^{-/-}$ mouse embryonic fibroblast (MEF) cells. RT-PCR analysis revealed that the amount of Gcn5 mRNA was similar in both WT and $Akt1^{-/-}$ MEFs. However, the protein level of Gcn5 was significantly increased in $Akt1^{-/-}$ MEF cells. The half life of Gcn5 was 1 hour in wild type whereas 8 hours in $Akt1^{-/-}$ MEF. These data all together, indicate that Gcn5 is post-transcriptionally down-regulated and the protein stability is negatively regulated by Akt1 in MEF cells.

• 대한한방부인과학회지
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• 제22권3호
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• pp.36-50
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• 2009

Purpose: This study was to determine the protective effects of Dioscoreae Rhizoma on the Mouse Embrio Fibroblast (MEF) cells exposed to the ultraviolet rays(UVA). Methods: The samples were assigned randomly to five groups; control group without any treatments, UVA group exposed only to UVA, DR group exposed only to the Dioscoreae Rhizoma, UVA-DR group exposed to UVA before being treated with the Dioscoreae Rhizoma, and DR-UVA group treated with the Dioscoreae Rhizoma before being exposed to UVA. The survival rate of cells, metabolic rate of cells, transformation of nucleus within cells, alteration of cell cycle, effects on the apoptosis, the change of the amount of protein related to cell cycle were measured in order to determine the cell protective effects of the Dioscoreae Rhizoma on each group. Results: 1. DR-UVA group has more cell protective effects compared to the UVA group in all experiments, indicating that the Dioscoreae Rhizoma protects skin from UVA physically and chemically. 2. UVA-DR group shows more efficiency compared to UVA group in rapid recovery of damaged cell and leading highly damaged cells to apoptosis, preventing the expression of abnormal cells. Conclusions: Dioscoreae Rhizoma has effects of protecting MEF cells from UVA, of recovering cells damaged by UVA, and of prohibiting the expression of abnormal cells.

• 생약학회지
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• 제45권2호
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• pp.127-134
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• 2014

A great interest is emerging about green tea as a tool against human cancer proliferation or inflammation, as pointed out by recent reports describing the inhibitory action of epigallocatechin gallate (EGCG) on angiogenesis, urokinase, metalloproteinases, and induction of inducible nitric oxide synthase. We proposed that EGCG may regulate a multi target signaling having wider spectra of action than those actions of single enzymes. CSK (c-terminal Src kinase) protein is a non-receptor tyrosine kinase involved in the cross-talk and mediation of many signaling pathways that promote cell proliferation, adhesion, invasion, migration, and tumorigenesis. Based on the knowledge that CSK activation is important for cancer proliferation we hypothesized that CSK could be a target of EGCG. Here we showed that EGCG effectively suppressed the growth of CSK MEF cell when compare with CSK knockout MEF cell growth. These results indicate that EGCG could be used as a chemoprevention to modulate CSK signal pathway in inflammatory processes and tumor formation.

• Food Science and Biotechnology
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• 제18권4호
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• pp.965-970
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• 2009

Oleuropein content of olive leaf extracts (OLE; ethanol extract) was evaluated by high performance liquid chromatography analysis. Oleuropein contents were $4.21{\pm}0.57$, $3.92{\pm}0.43$, $0.32{\pm}0.03$, $5.76{\pm}0.32$, and $32.47{\pm}0.25$ mg/100 g for ethanol extract, and hexane, chloroform, ethyl acetate, and butanol fraction, respectively. The removal of DPPH free radical increased in OLE and all 5 fractions of OLE in a concentration dependent manner. In order to investigate the antioxidant effect of OLE in vitro, 80%(v/v) ethanol OLE, $H_2O_2$, or combined treatment of 80%(v/v) ethanol OLE and $H_2O_2$ were applied on mouse embryonic fibroblast (MEF) cells. Cells were damaged by oxidative stress decreased their viability followed by increasing concentration of $H_2O_2$, but co-treatment of OLE and $H_2O_2$ showed an increase in cell growth about 20% compare to the cells treated with $H_2O_2$. OLE suppresses cytotoxicity induced by $H_2O_2$ in dose dependent manner. OLE treatment on MEF cells was also examined by analyzing cell cycle and apoptotic rate using flow cytometry. Apoptotic and necrotic cell accumulation was decreased in addition of OLE to $H_2O_2$ compare to the oxidative damaged cells. Taken together, these results demonstrated that OLE suppresses cytotoxicity induced by $H_2O_2$ and protect cells against oxidative stress on MEF cells.

• Molecules and Cells
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• 제28권1호
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• pp.1-5
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• 2009

Vascular endothelial growth factor (VEGF) is essential for many angiogenic processes both in normal and pathological conditions. However, the signaling pathways involved in VEGF-induced angiogenesis are incompletely understood. The protein kinase D1 (PKD1), a newly described calcium/calmodulin-dependent serine/threonine kinase, has been implicated in cell migration, proliferation and membrane trafficking. Increasing evidence suggests critical roles for PKD1-mediated signaling pathways in endothelial cells, particularly in the regulation of VEGF-induced angiogenesis. Recent studies show that class IIa histone deacetylases (HDACs) are PKD1 substrates and VEGF signal-responsive repressors of myocyte enhancer factor-2 (MEF2) transcriptional activation in endothelial cells. This review provides a guide to PKD1 signaling pathways and the direct downstream targets of PKD1 in VEGF signaling, and suggests important functions of PKD1 in angiogenesis.

• Biomolecules & Therapeutics
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• 제18권4호
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• pp.454-462
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• 2010

The present study investigated the neuroprotective effect of Carpinus tschonoskii MAX and its intracellular protective mechanism on 6-hydroxydopamine (6-OHDA)-induced oxidative damage in PC12 cells. We found that pretreatment of PC12 cells with C. tschonoskii extract significantly inhibited the cell death induced by 6-OHDA in a dose dependent manner. C. tschonoskii extract decreased 6-OHDA-induced apoptotic events such as chromatin condensation, DNA fragmentation, the decrease of Bcl-2/Bax ratio, caspase-3 activation and PARP cleavage. C. tschonoskii extract also reduced generation of 6-OHDA-induced reactive oxygen species and nitric oxide. Furthermore, C. tschonoskii extract up-regulated the myocyte enhancer factor 2 D (MEF2D), a critical transcription factor for neuronal survival, and Akt activity, whereas it inhibited the activity of ERK1/2 and JNK. The results suggest that C. tschonoskii extract decreases 6-OHDA-induced oxidative stress and could prevent PC12 cell apoptosis induced by 6-OHDA via the up-regulation of MEF2D and Akt activity, and thus may have application in developing therapeutic agents for Parkinson's disease.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1998년도 공동 춘계학술대회
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• pp.58.1-58
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• 1998

No Abstract, See Full Text

• 한국동물학회:학술대회논문집
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• 한국동물학회 1999년도 공동 춘계학술대회
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• pp.78.1-78
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• 1999

No Abstract, See Full Text

• Clinical and Experimental Reproductive Medicine
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• 제33권4호
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• pp.265-272
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• 2006

목 적: 본 연구는 생쥐 포배기 배아로부터 내세포괴를 분리하는 방법과 지지세포의 종류와 mitomycin C 처리 시간이 내세포괴 colony 형성률에 미치는 영향을 관찰하기 위해 시행되었다. 연구방법: 일반적인 면역절제술, 주사바늘을 이용한 부분 영양막세포 절개법, 포배기 배아 공배양법으로 내세포괴를 분리한 후, 상업적으로 구입이 가능한 STO 또는 직접 제조한 생쥐 배아섬유아세포 (pMEF)를 지지세포로 이용하여 배양하였다. 또한, mitomycin C를 1, 2, 3시간 동안 처리한 각각의 지지세포에서 7일 동안 배양한 후, 내세포괴 colony 형성률을 살펴보았다. 결 과: STO 지지세포에서는 부분 영양막세포 절개법을 사용한 경우 (52%)가 면역절제술 (12%)이나 포배기 배아 공배양법 (16%)을 사용한 경우보다 내세포괴 colony 형성률이 유의하게 높았다 (p<0.05). pMEF 지지세포에서의 형성률은 부분 영양막세포 절개법을 사용한 경우 (88%)와 포배기 배아 공배양법 (82%)을 사용한 경우가 면역절제술 (16%)을 사용한 경우보다 높았다 (p<0.05). STO와 pMEF 모두에서, 2시간 mitomycin C 처리군 (52%, 88%)이 1시간 처리군 (9%, 42%)과 3시간 처리군 (18%, 76%)보다 높은 내세포괴 colony 형성률을 보여주었다 (p<0.05). 결 론: 이상의 결과는 부분 영양막세포 절개법이 생쥐 포배기 배아로부터 내세포괴를 분리하는 가장 효과적인 방법이며, 가장 적절한 mitomycin C 처리 시간은 2시간이라는 것을 보여준다. 그러나 이와 같은 부분 영양막세포 절개법의 효용성을 보다 명확하게 확인하기 위해서는 분리한 내세포괴를 계대배양하여 줄기세포주로서의 특성을 확인하는 실험이 추가적으로 필요할 것으로 생각된다.

• 한국해양환경ㆍ에너지학회지
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• 제14권2호
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• pp.107-113
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• 2011

해수유동모델의 검증 및 평가를 위해 적용되는 또는 적용가능한 10종류의 모델 오차평가방법 - 네가지의 정량적 평가방법(절대평균오차, 평균제곱근 오차, 상대적 절대평균오차, 백분율모델오차)과 여섯가지의 정성적 평가방법(상관계수, 신뢰지수, 일치지수, 모델효율성, 비용함수, 잔여량계수) - 을 소개하고, 실제 조위, 유속, 염분관측치와 3차원 곡선형 모델(CH3D)에서 구해진 플로리다 하구에서의 수치해에 이들 모델 오차평가방법들을 적용하였다. 조위 및 유속평가시 절대평균오차, 평균제곱근 오차, 상대적 절대평균오차, 상관계수, 일치지수, 모델효율성, 비용함수, 잔여량계수 등이 적합하였다. 그리고 염분평가시 절대평균오차, 평균제곱근 오차, 상대적 절대평균오차, 백분율모델오차, 상관계수, 신뢰지수, 비용함수, 잔여량계수 등의 사용이 타당하였다. 정량/정성적 평가방법들이 서로 유사한 평가경향을 보여 줌으로써, 상호간의 신뢰성도 보여 주었다. 다양한 모델 오차평가방법을 통하여 계산된 평가값을 토대로, 본 연구에서는 조위, 유속, 염분이 잘 재현된 해수유동모델의 평가범위를 제시하였다. 조위의 경우 상대적 절대평균 오차는 10%이내, 상관계수는 0.95이상, 일치지수는 0.98이상, 모델효율성은 0.93이상, 비용함수는 0.21이내이며, 유속의 경우 상대적 절대평균오차는 20%이내, 상관계수는 0.7이상, 일치지수는 0.8이상, 모델효율성은 0.5이상, 비용 함수는 0.5이내이며, 염분의 경우 상대적 절대평균오차와 백분율모델오차는 10%이내, 상관계수는 0.9이상, 신뢰지수는 1.15이내, 비용함수는 0.1이내 이다.