• The Journal of Korean Obstetrics and Gynecology
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• v.22 no.3
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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.

• The Journal of Internal Korean Medicine
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• v.28 no.2
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• pp.333-345
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• 2007

Determination and differentiation of cells in the skeletal muscle lineage is positively regulated by cell-cell contact. differentiation proteins proposed to mediate this effect include both classical MyoD and MEF members : potential interactions between the promyogenic activities of these classes of protein, however, are unknown. We show here that MyoD and MEF, two promyogenic family members that determine to each other in a cis fashion, form ineraction with MyoD- and MEF. These proteins contain myosin heavy chains and are enriched at sites of cell-cell contact between myoblasts, Therefore, In differentiation of MyoD MEF from CST (Chungsimyeonjatang) interact dependently, suggesting that the interactions occur in a cis fashio : consistent with this conclusion, MyoD-mediated differentiation is required for myoblast to occur by CST. Inhibition in myoblasts of a MyoD by STP in its ability to associate with MEF interferes with differentiation as assessed by morphological and transcription level, suggesting that this interaction is functionally important in myogenesis. Also, some of the differentiation-mediated proteins that are required for myogenesis seem to be based on interdependent activities of promyogenic classical SMAD-subfamilly.

• Natural Product Sciences
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• v.2 no.1
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• pp.29-36
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• 1996

This study was to evaluate the antitumor and immunopotentiation effects of Manda Enzyme (ME). Oral administration of ME (0.2ml/mouse) to tumor bearing mice significantly prolonged survival rate compared to the control group with the prolongation ratio of 40%. The inhibition ratios for the first and the second experiments were 51.8% and 26.4%, respectively. Only the spleen index was significantly increased in the MEF-treated group, but not in the control group. Gamma globulin level of the MEF-treated group was elevated when mice were injected with sarcoma-180 cells on the left groin. Activities of natural killer (NK) and lymphokineactivated killer (LAK) cells were observed by $^{51}Cr-release$ method. Activities of NK cell against YAC-1 cells were significantly increased in the MEF treated group. And LAK cell activities against P815 cells were also significantly increased in the experimental group. These observations, therefore, suggest that ME may have an anticancer effect and immunopotentiating effect in vivo.

• Biomedical Science Letters
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• v.18 no.2
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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.

• Nutrition Research and Practice
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• v.13 no.2
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• pp.95-104
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• 2019

BACKGROUND/OBJECTIVES: Inflammatory Bowel Disease (IBD) has rapidly escalated in Asia (including Korea) due to increasing westernized diet patterns subsequent to industrialization. Factors associated with endoplasmic reticulum (ER) stress are demonstrated to be one of the major causes of IBD. This study was conducted to investigate the effect of Lycium barbarum (L. barbarum) on ER stress. MATERIALS/METHODS: Mouse embryonic fibroblast (MEF) cell line and polarized Caco-2 human intestinal epithelial cells were treated with crude extract of the L. chinense fruit (LF). Paracellular permeability was measured to examine the effect of tight junction (TJ) integrity. The regulatory pathways of ER stress were evaluated in MEF knockout (KO) cell lines by qPCR for interleukin (IL) 6, IL8 and XBP1 spliced form (XBP1s). Immunoglobulin binding protein (BiP), XBP1s and CCAAT/enhancer-binding homologous protein (CHOP) expressions were measured by RT-PCR. Scanning Ion Conductance Microscopy (SICM) at high resolution was applied to observe morphological changes after treatments. RESULTS: Exposure to LF extract strengthened the TJ, both in the presence and absence of inflammation. In polarized Caco-2 pretreated with LF, induction in the expression of proinflammatory marker IL8 was not significant, whereas ER stress marker XBP1s expression was significantly increased. In wild type (wt) MEF cells, IL6, CHOP and XBP1 spliced form were dose-dependently induced when exposed to $12.5-50{\mu}g/mL$ extract. However, absence of XBP1 or $IRE1{\alpha}$ in MEF cells abolished this effect. CONCLUSION: Results of this study show that LF treatment enhances the barrier function and reduces inflammation and ER stress in an $IRE1{\alpha}$-XBP1-dependent manner. These results suggest the preventive effect of LF on healthy intestine, and the possibility of reducing the degree of inflammatory symptoms in IBD patients.

• Physical Therapy Korea
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• v.14 no.1
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• pp.28-36
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• 2007

The aim of this study was to identify the effect of suspension unloading (SU) and electrical stimulation upon the development of neonatal muscular system. For this study, the neonatal rats were randomly divided into three groups: a control group, an experimental group I, and an experimental group II. The SU for experimental group I and II was applied from postnatal day (PD) 5 to PD 30. The electrical stimulation for soleus muscle of experimental group IIwas applied from PD 16 to PD 30 using neuromuscular electrical stimulation (NMES), which gave isometric contraction with 10 pps for 30 minutes twice a day. In order to observe the effect of SU and ES, this study observed myocyte enhancer factor 2C (MEF2C) and vascular endothelial growth factor (VEGF) immunoreactivity in the soleus muscles at PD 15 and PD 30. In addition, the motor behavior test was performed through footprint analysis at PD 30. The following is the result. At PD 15, the soleus muscles of experimental group Iand II had significantly lower MEF2C, VEGF immunoreactivity than the control group. It proved that microgravity conditions restricted the development of the skeletal muscle cells at PD 15. At PD 30, soleus muscles of the control group and experimental group II had significantly higher MEF2C, VEGF, immunoreactivity than experimental group I. It proved that the NMES facilitated the development of the skeletal muscle cells. At PD 30, it showed that SU caused the decrease in stride length of parameter of gait analysis and an increase in toe-out angle, and that the NMES decreased these variations. These results suggest that weight bearing during neonatal developmental period is essential for muscular development. They also reveal that NMES can encourage the development of muscular systems by fully supplementing the effect of weight bearing, which is an essential factor in the neonatal developmental process.

• Molecules and Cells
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• v.28 no.1
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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.

• Food Science and Biotechnology
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• v.18 no.4
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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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• v.38 no.4
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• pp.343-348
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• 2015

Fiber type-specific programs controlled by the transcription factor MEF2 dictate muscle functionality. Here, we show that HDAC4, a potent MEF2 inhibitor, is predominantly localized to the nuclei in fast/glycolytic fibers in contrast to the sarcoplasm in slow/oxidative fibers. The cytoplasmic localization is associated with HDAC4 hyper-phosphorylation in slow/oxidative-fibers. Genetic reprogramming of fast/glycolytic fibers to oxidative fibers by active CaMKII or calcineurin leads to increased HDAC4 phosphorylation, HDAC4 nuclear export, and an increase in markers associated with oxidative fibers. Indeed, HDAC4 represses the MEF2-dependent, PGC-$1{\alpha}$-mediated oxidative metabolic gene program. Thus differential phosphorylation and localization of HDAC4 contributes to establishing fiber type-specific transcriptional programs.

• Biomolecules & Therapeutics
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• v.18 no.4
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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.