• Environmental Analysis Health and Toxicology
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• v.20 no.3 s.50
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• pp.229-235
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• 2005

태양광선,특히 자외선 B에 대한 환경적 노출은 편평세포암과 기저세포암을 포함하는 흑색선종 이외의 피부암과 크게 관련된다고 알려져 있다. 염기 류신 지퍼계 전사조절인자인 CChAT/enhancer binding protein-alpha는 표피 각질형성세포에서 다량으로 발현되었고, 각질형성세포의 증식을 억제하며 피부암 발생을 억제하는 유전자로서의 역할이 암시된 바 있다. 최근 자외선 B가 각질형성세포에서 p53에 의한 CCAAT/enhanrer binding protein-alpha의 발현을 강력하게 유도한다는 것이 보고되었다. 이러한 CCAAT/enhancer binding protein-alpha 단백질 발현의 유도는 세포 성장 억제 세포고사와 함께 일어났다. 이 연구는 glycogen synthase kinase-3 길항제가 자외선 B에 의한 CCAAT/enhancer binding protein-alpha 유도를 억제하며 변이 kinase-불활성 GSK의 강제 발현은 자외선 B가 CCAAT/enhancer binding protein-alpha전사조절부위 활성의 증가를 억제한다는 것을 보여주었다. 즉 자외선 B에 의한 CCAAT/enhancer binding protein-alpha의 유도가 p53과 활성 glycogen synthase kinase-3에 의한 것이라는 것을 증명하였다.

• Development and Reproduction
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• v.26 no.2
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• pp.49-58
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• 2022

The differentiation and development of preadipocyte into mature adipocyte are regulated by transcription factors, such as CCAAT enhancer binding protein (Cebp) gene family and sterol regulatory element binding transcription factor 1 (Srebp1). Steroid hormones give influences on the development and function of adipocyte. The present research examined expression patterns of CCAAT enhancer binding protein alpha (Cebpa), CCAAT enhancer binding protein beta (Cebpb), CCAAT enhancer binding protein gamma (Cebpg), sterol regulatory element binding transcription factor 1 (Srebp1), androgen receptor (Ar), and estrogen receptors (Esr) among different epididymal fat parts during postnatal period by quantitative real-time polymerase chain reaction. In the distal epididymal fat, expression of Cebpa, Cebpb, Cebpg, Srebp1, Ar, and Esr2 was increased until 12 months of age, while expression of Esr1 was decreased at 5 months of age and was not detectable after 8 months of age. In the proximal epididymal fat, transcript levels of Cebps and Srebp1 were increased at 8 months of age, followed by decreases of Cebpb and Cebpg transcript levels at 12 months of age. An additional increase of Srebp1 expression was observed at 12 months of age. Expression of Ar and Esr2 were increased until 8 months of age, followed by a drop of Ar expression level at 12 months of age. Expression pattern of Esr1 was similar to that in the distal epididymal fat. In the tail epididymal fat, expression of Cebpa, Cebpg, Srebp1, Ar, and Esr2 was increased with age. Esr1 was not detectable at all. The highest level of Cebpb was observed at 8 months of age. These data suggest the possibility of developmental and functional differentiation among the epididymal fat parts.

• Journal of Life Science
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• v.23 no.4
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• pp.510-517
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• 2013

This study was performed to evaluate the antiobesity effect of supercritical fluid extracts (SFC) and marc methanol extracts (SFM) from Cinnamomum verum in 3T3-L1 preadipocytes. In inducing the differentiation of 3T3-L1 preadipocytes in the presence of an adipogenic cocktail, iso-butylmethylanthine (IBMX), dexamathasone, and insulin, treatment with fraction residue SFC and SFM. SFC significantly reduced the mRNA expression of the transcription factor peroxisome proliferator-activate-dreceptor-${\gamma}$ ($PPAR{\gamma}$), the sterol regulatory-element-binding protein-1c (SREBP1c), and the CCAAT enhancer-binding-protein ${\alpha}$ ($C/EBP{\alpha}$) in a concentration-dependent manner. Moreover, SFC markedly down-regulated acyl-CoA synthetase-1 (ASC1), fatty acid synthesis (FAS), fatty acid transport-1 (FATP1), fatty acid binding protein 4 (FABP4), and perilipin. These findings suggest that SFC may be a potential therapeutic adjunct for obesity by targeting the differentiation of preadipocytes, as well as their functions.

• Journal of Animal Science and Technology
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• v.46 no.6
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• pp.909-916
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• 2004

CCAAT/enhancer binding proteins(C/EBP) are a group of transcription factors expressed during preadipocyte differentiation. In the C/EBPs, C/EBPa plays an important role in lipid deposition and adipocyte differentiation. In this studies, we report the identification, characterization, and expression of a Hanwoo CIEBP$\alpha$ The Hanwoo C/EBP$\alpha$DNA includes a 1059 bp open reading frame encoding a protein of 353 amino acids. The CIEBPa amino acid sequences of the Hanwoo show strong conservation with the corresponding sequences reported in other species. The distribution of C/EBP$\alpha$ mRNA in various tissues of Hanwoo aged 12 months were investigated using Northern blotting analysis. The highest expression was detected in adipose tissue and more lower expression was detected in colon and lung. We also identified expression of C/EBPa mRNA in Hanwoo sirloin and adipose tissue aged 12, 26, and 30 months by real-time RT-PCR. The higest expression were detected at 26 months in the sirloin and at 12 and 26 months in the adipose tissue.

• BMB Reports
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• v.43 no.2
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• pp.140-145
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• 2010

The present study investigated whether the mammalian target of rapamycin (mTOR) signal pathway is involved in the regulation of high glucose-induced intramuscular adipogenesis in porcine muscle satellite cells. High glucose (25 mM) dramatically increased intracellular lipid accumulation in cells during the 10-day adipogenic differentiation period. The expressions of CCAAT/enhancer binding protein-$\alpha$ (C/EBP-$\alpha$) and fatty acid synthase (FAS) protein were gradually enhanced during the 10-day duration while mTOR phosphorylation and sterol-regulatory- element-binding protein (SREBP)-1c protein were induced on day 4. Moreover, inhibition of mTOR activity by rapamycin resulted in a reduction of SREBP-1c protein expression and adipogenesis in cells. Collectively, our findings suggest that the adipogenic differentiation of porcine muscle satellite cells and a succeeding extensive adipogenesis, which is triggered by high glucose, is initiated by the mTOR signal pathway through the activation of SREBP-1c protein. This process is previously uncharacterized and suggests a cellular mechanism may be involved in ectopic lipid deposition in skeletal muscle during type 2 diabetes.

• Journal of Applied Biological Chemistry
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• v.60 no.1
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• pp.23-28
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• 2017

Amomum tsao-ko used as a traditional oriental herbal medicine, is indigenous to several Asia countries. In this study, we investigated anti-obesity activity of the ethanol extract of Amomum Taso-ko (A. tsao-ko). The ethanol extract of A. tsao-ko inhibited adipocyte differentiation using Oil Red O assay in 3T3-L1 cells. Inhibitory effect of the ethanol extract of A. tsao-ko on adipogenesis was modulated by down-regulation adipogenic transcriptional factor such as peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$), CCAAT-enhancer-binding protein ${\alpha}$ ($C/EBP{\alpha}$) and suppressed expression of fatty acid synthase, aP2, and resistin. We demonstrated that A. tsao-ko significantly inhibited adipogenesis and reduced $PPAR{\gamma}$ and $C/EBP{\alpha}$ expression in a dose-dependent manner. These results suggest that A. tsao-ko has an anti-obesity effect by inhibition of adipogenic transcription factor and adipocyte-specific genes in 3T3-L1 cells.

• Microbiology and Biotechnology Letters
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• v.45 no.1
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• pp.27-34
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• 2017

$C/EBP{\beta}$ and $C/EBP{\delta}$ are required for the initiation of adipogenesis and induce the expression of key adipogenic regulators, such as $PPAR{\gamma}$ and $C/EBP{\alpha}$. In the present study, we have examined the effects of silibinin and its possible molecular mechanisms in regulating adipocyte differentiation and expression of $C/EBP{\beta}$ and $C/EBP{\delta}$ in the early stage of adipogenesis. Silibinin statistically significantly inhibits intracellular lipid accumulation and the mRNA expression of various genes involved at different stages during adipogenesis. Silibinin also suppresses expression of lipoprotein lipase (LPL), fatty acid binding protein 4 (AP2), and adiponectin in 3T3-L1 adipocytes. Thus, the anti-adipogenic effect of silibinin seems to originate from the ability to inhibit the expression of $C/EBP{\beta}$ and $C/EBP{\delta}$. Furthermore, silibinin decreases cell viability for differentiation period and induces apoptotic cell death through capspase-3 activation.

• Journal of Life Science
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• v.32 no.7
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• pp.542-549
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• 2022

Polymethoxyflavones (PMFs) are flavonoids mainly found in citrus fruits and have been reported to exhibit a wide range of bioactivities, including anti-obesity, anti-cancer, and anti-inflammatory actions. To utilize PMFs as functional materials, it is necessary to develop a simple method of obtaining PMFs from citrus tissues containing a large amount of PMFs. It has been reported that Jinkyool (C. sunki Hort ex. Tanaka) peel contained a large amount of PMFs, but there are no studies on PMFs isolated from its leaves. In this study, we established a simple procedure for obtaining the PMF-rich fraction (PRF) from the leaves of Jinkyool and investigated the effects of PRF on lipid metabolism in 3T3-L1 cells. PRF inhibited lipogenesis during the differentiation of 3T3-L1 preadipocytes. It decreased the expression of peroxisome proliferator-activated receptor gamma (PPAR𝛾) and CCAAT/enhancer binding protein alpha (CEBP𝛼), FAS, and adipocyte fatty-acid-binding protein 2 (aP2). In mature 3T3-L1 adipocytes, PRF increases the phosphorylation of protein kinase A (PKA)/hormone-sensitive lipase (HSL), which are key factors involved in lipolysis. Moreover, it increases the phosphorylation of the AMP-activated protein kinase (AMPK)/acetyl-CoA carboxylase (ACC) involved in fatty acid oxidation. These results suggest that PRF from Jinkyool leaves can be used as an anti-obesity agent with the action of inhibiting lipogenesis and promoting lipolysis and fatty acid oxidation in 3T3-L1 adipocytes.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.186-196
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• 2023

Dyglomera^® is an aqueous ethanol extract derived from the fruit and pods of Dichrostachys glomerata. A previous study has revealed that Dyglomera regulates adipogenesis and lipolysis by modulating AMP-activated protein kinase (AMPK) phosphorylation and increased expression levels of lipolysis-related proteins in white adipose tissue of high fat diet-induced mice and 3T3-L1 adipocyte cells. To further investigate mechanisms of Dyglomera, additional studies were performed using 3T3-L1 cells. Results revealed that Dyglomera downregulated adipogenesis by inhibiting the protein kinase B/mammalian target of rapamycin signaling pathway and reconfirmed that it downregulated gene expression levels of proliferator-activated receptor (PPAR)-γ, CCAAT enhancer binding protein α, sterol-regulation element-binding protein-1c. Dyglomera also reduced adipokines such as tumor necrosis factor alpha, interleukin-1β, and interleukin 6 by regulating leptin expression. Moreover, Dyglomera promoted beige-and-brown adipocyte-related phenotypes and regulated metabolism by increasing mitochondrial number and expression levels of genes such as T-box protein 1, transmembrane protein 26, PR domain 16, and cluster of differentiation 40 as well as thermogenic factors such as uncoupling protein 1, proliferator-activated receptor-gamma co-activator-1α, Sirtuin 1, and PPARα through AMPK activation. Thus, Dyglomera not only can inhibit adipogenesis, but also can promote lipolysis and thermogenesis and regulate metabolism by affecting adipokine secretion from 3T3-L1 adipocytes.

• Journal of Life Science
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• v.29 no.9
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• pp.1016-1022
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• 2019

Owing to increased interest in preventing obesity in an aging society, both men and women spend considerable amount of cost on obesity managements. In this study, we investigated the natural substances on anti-obesity activities in 3T3-L1 pre-adipocytes. Also, to improve anti-obesityeffects, research using 3T3-L1 pre-adipocytes cells is crucial. The anti-obesity effect of 70% ethanol extract from Torilis Japonica Decandolle on the differentiation of 3T3-L1 pre-adipocytes to adipocytes was investigated by suppressing adipocyte differentiation and lipid accumulation with Oil Red O assay, and western blot analysis. Compared to the control, 70% ethanol extract of Torilis Japonica Decandolle was significantly inhibited adipocyte differentiation and intracellular triglyceride (TG) level at a concentration of $100{\mu}g/ml$. To determine the mechanism of reduction in TG content, we determined the level of protein expression of obesity-related proteins, such as peroxisome-proliferatorsactivated-receptor-${\gamma}$ ($PPAR{\gamma}$) and CCAAT enhancer-binding-proteins-${\alpha}$ ($C/EBP{\alpha}$), and Acetyl-CoA carboxylase (ACC) phosphorylation. As a results, 70% ethanol extract of Torilis Japonica Decandolle significantly decreased protein expression of $PPAR{\gamma}$, $C/EBP{\alpha}$ and ACC phosphorylation. These results indicate that 70% ethanol extract of Torilis Japonica Decandolle is the most effective candidate for preventing obesity. However further studies will be needed to identify the active compounds that confer the anti-obesity activity of Torilis Japonica Decandolle.