• 미생물학회지
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• 제47권4호
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• pp.342-347
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• 2011

인체의 바이러스 감염 방어기전에서 T 림프구는 중요한 역할을 한다. 하지만, 만성 C형 간염 바이러스의 일차적 복제장소인 간염 환자의 간에서 분리된 HCV 특이 T 림프구는 심각한 기능결핍을 보인다. 이러한 T 림프구 기능결핍의 이유로는 PD-1, CTLA-4 등 면역억제 물질의 발현, 또는 간에서 특이적으로 유도되는 면역내성(immune tolerance)이 있으나, 간세포(hepatocytes)와 HCV 특이 T 림프구의 상호작용에 대해서는 명확하게 확립되어 있지 않다. 따라서 본 연구에서는 HLA(human leukocyte antigen) A2+ 간암세포주(human hepatoma cell line; huh7.5)가 항원제시(antigen presentation)를 통해 효과적으로 HCV 특이 T 림프구를 활성화시키며 간암세포주(huh7.5) 표면의 PD-L (program death ligand) 1 발현은 T림프구의 활성을 감소시켜 면역조절의 가능성이 있음을 시사하였다. 또한, HCV 특이 tetramer 반응은 T 림프구의 과도한 활성으로 자기사멸(apoptosis)의 경로에 있음을 caspase 3 활성으로 확인하였고, 역시 PD-L1의 발현이 T 림프구를 자기사멸(apoptosis)로부터 구제하여 caspase 3 활성이 감소하는 것을 확인하였다. 이는 PD-L1과 간성(liver) T 림프구 표면의 PD-1 결합이 T 림프구의 자기사멸을 막고, 또한 그 기능을 회복시켜 만성 C형 간염 치료에 응용될 수 있음을 시사한다.

• Nutrition Research and Practice
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• 제11권3호
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• pp.198-205
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• 2017

BACKGROUND/OBJECTIVES: The anti-diabetic activity of pear through inhibition of ${\alpha}-glucosidase$ has been demonstrated. However, little has been reported about the effect of pear on insulin signaling pathway in obesity. The aims of this study are to establish pear pomace 50% ethanol extract (PPE)-induced improvement of insulin sensitivity and characterize its action mechanism in 3T3-L1 cells and high-fat diet (HFD)-fed C57BL/6 mice. MATERIALS/METHODS: Lipid accumulation, monocyte chemoattractant protein-1 (MCP-1) secretion and glucose uptake were measure in 3T3-L1 cells. Mice were fed HFD (60% kcal from fat) and orally ingested PPE once daily for 8 weeks and body weight, homeostasis model assessment of insulin resistance (HOMA-IR), and serum lipids were measured. The expression of proteins involved in insulin signaling pathway was evaluated by western blot assay in 3T3-L1 cells and adipose tissue of mice. RESULTS: In 3T3-L1 cells, without affecting cell viability and lipid accumulation, PPE inhibited MCP-1 secretion, improved glucose uptake, and increased protein expression of phosphorylated insulin receptor substrate 1 [p-IRS-1, ($Tyr^{632})$)], p-Akt, and glucose transporter type 4 (GLUT4). Additionally, in HFD-fed mice, PPE reduced body weight, HOMA-IR, and serum lipids including triglyceride and LDL-cholesterol. Furthermore, in adipose tissue, PPE up-regulated GLUT4 expression and expression ratio of p-IRS-1 ($Tyr^{632})/IRS$, whereas, down-regulated p-IRS-1 ($Ser^{307})/IRS$. CONCLUSIONS: Our results collectively show that PPE improves glucose uptake in 3T3-L1 cells and insulin sensitivity in mice fed a HFD through stimulation of the insulin signaling pathway. Furthermore, PPE-induced improvement of insulin sensitivity was not accompanied with lipid accumulation.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 춘계학술발표회
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• pp.80-80
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• 2018

Chlorogenic acid is a phenolic compound found in Cudrania tricuspidata fruits. In the present study, the effect of chlorogenic acid on the inhibition of adipogenesis in 3T3-L1 adipocytes was investigated. Cells were stained with Oil red O reagent to detect lipid droplets in adipocytes. The 3T3-L1 cells were lysed and measured for intracellular triglyceride and adipokine by ELISA kit. The protein expression of adipogenesis-related gene was evaluated by Western blot analysis. Chlorogenic suppressed lipid droplet and intracellular triglyceride accumulation in a concentration manner and also decreased secretion of adipokines such as leptin and adiponectin, compared with fully differentiated adipocytes. Treatment of 3T3-L1 cells with chlorogenic acid reduced the protein levels of peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) and, CCAAT/enhancer binding proteins alpha ($C/EBP{\alpha}$). This indicates that chlrogenic acid was effective as an anti-obesity agent by repressing the differentiation of 3T3-L1 into adipocytes and inhibiting triglyceridef formation in adipocyte and that it exerts its role mainly through the significant down-regulation of $PPAR{\gamma}$ and $C/EBP{\alpha}$.

• Preventive Nutrition and Food Science
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• 제9권4호
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• pp.336-341
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• 2004

Leptin, resisitn and PAI-1 (plasminogen activator inhibitor-1) are synthesized and secreted by rodent fat cells and recently postulated to be an important link to obesity. This study was conducted to characterize the hormonal regulation of leptin, resistin, and PAI-1 gene expression in the 3T3-L1 adipocytes. The cells were treated with 0.5 $\mu$M insulin, 1 $\mu$M dexamethasone (Dex), or 0.05 $\mu$M triiodothyronine (T3) for 72 hours. The mRNA levels of each peptide were measured by semi-quantitative RT-PCR. The mRNA level of the leptin-producing ob gene was significantly increased by insulin, Dex, and T3 by 3.2-, 3.1- and 2.7-fold, respectively, compared to the control (p < 0.05). The level of resistin mRNA was increased by insulin, Dex, and T3 by 2.7-, 2.5- and 2-fold, respectively, compared to the control (p < 0.05). Likewise, the level of PAI-1 mRNA was significantly increased by insulin, Dex, and T3 compared to the control (p < 0.05). Taken together, our results suggest that insulin, Dex, and T3 may regulate the gene expression of leptin, resistin, and PAI-1 in 3T3-L1 adipocytes.

• Preventive Nutrition and Food Science
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• 제21권1호
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• pp.62-67
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• 2016

Green tea (Camellia sinensis) is one of the most popular beverages in the world and has been acknowledged for centuries as having significant health benefits. (-)-Epigallocatechin-3-gallate (EGCG) is the most abundant catechin in green tea, and it has been reported to have health benefit effects. Peroxisome proliferator-activated receptor ${\gamma}$ coactivator $(PGC)-1{\alpha}$ is a crucial regulator of mitochondrial biogenesis and hepatic gluconeogenesis. The objective of this study was to investigate whether EGCG from green tea can affect the ability of transcriptional regulation on $PGC-1{\alpha}$ mRNA expression in HepG2 cells and 3T3-L1 adipocytes. To study the molecular mechanism that allows EGCG to control $PGC-1{\alpha}$ expression, the promoter activity levels of $PGC-1{\alpha}$ were examined. The $PGC-1{\alpha}$ mRNA level was measured using quantitative real-time PCR. The -970/+412 bp of $PGC-1{\alpha}$ promoter was subcloned into the pGL3-Basic vector that includes luciferase as a reporter gene. EGCG was found to up-regulate the $PGC-1{\alpha}$ mRNA levels significantly with $10{\mu}mol/L$ of EGCG in HepG2 cells and differentiated 3T3-L1 adipocytes. $PGC-1{\alpha}$ promoter activity was also increased by treatment with $10{\mu}mol/L$ of EGCG in both cells. These results suggest that EGCG may induce $PGC-1{\alpha}$ gene expression, potentially through promoter activation.

• Journal of Nutrition and Health
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• 제52권1호
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• pp.17-25
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• 2019

본 연구에서는 댕댕이나무 열매 추출물이 3T3-L1과 마우스 지방유래줄기세포의 지방 분화유도 및 지방생성에 미치는 영향을 살펴보았다. 3T3-L1에 댕댕이나무 열매 추출물을 처리하였을 때, 농도의존적으로 지방구의 생성을 줄였고 지방세포 분화에 있어서 중요한 전사인자인 $PPAR{\gamma}$, $C/EBP{\alpha}$, SREBP1의 발현을 억제시켜 지방 합성이 감소됨을 확인하였다. 또한, 마우스 지방에서 분리한 줄기세포의 지방 분화과정에서도 댕댕이나무 열매 추출물이 $PPAR{\gamma}$, $C/EBP{\alpha}$, SREBP1의 단백질 발현을 감소시켜 지방 축적을 농도 의존적으로 억제하였다. 이상의 결과로 댕댕이나무 열매 추출물은 세포독성이 없는 농도에서 지방 세포의 분화를 억제 하는 것으로 확인되어 항비만 기능성 소재로서의 활용 가능성이 있을 것으로 사료된다.

• 한방비만학회지
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• 제23권2호
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• pp.69-77
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• 2023

Objectives: Atriplex gmelinii C. A. Meyer is a halophyte belonging to the Chenopodiaceae family, and its young leaves and stems are used as fodder for livestock. The aim of the present study was to investigate the effects of A. gmelinii extract and its solvent fractions on lipid accumulation during adipogenesis of 3T3-L1 preadipocytes. Methods: The samples of A. gmelinii were separately extracted using methylene chloride and methanol. Subsequently, they were combined to formulate the initial extract, which was then partitioned based on polarity to prepare solvent fractions. Oil Red O staining was employed to measure lipid accumulation during the differentiation of 3T3-L1 preadipocytes. To verify cytotoxicity in 3T3-L1 cells, MTT assays were conducted. The expression levels of transcription factors in 3T3-L1 preadipocytes were measured through Western blotting analysis. Results: At 50 ㎍/mL, treatment of A. gmelinii extract and its solvent fractions during the differentiation of 3T3-L1 preadipocytes significantly diminished lipid accumulation with no noteworthy cytotoxicity on cell viability. Additionally, when investigating the biochemical pathways that underlie the prevention of lipid accumulation using solvent fractions, it was found that the n-BuOH and n-hexane fractions significantly decreased the expression of key transcription factors involved in the generation of fat, such as peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer binding protein α (C/EBPα), and sterol regulatory element-binding protein-1c (SREBP1c). Conclusions: These findings indicate that A. gmelinii can effectively reduce the accumulation of fat in 3T3-L1 adipocytes, making it a potentially valuable material for mitigating and preventing obesity.

• 한국약용작물학회지
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• 제23권3호
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• pp.245-252
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• 2015

This study was carried out to investigate the effects of Salvia plebeia R. Br. ethanolic extract with different aspects (stem/leaf and whole plant) on differentiation and lipid accumulation in 3T3-L1 preadipocytes. The morphological changes and the degrees of lipid accumulation in 3T3-L1 cells were measured by Oil Red O staining and intra-cellular triglyceride (TG) assay. The mRNA expressions of special peroxisome proliferation activated receptor- genes (PPAR), CCAAT/ enhancer-binding protein (C/$EBP{\alpha}$), fatty acid synthase (FAS) and lipoprotein lipase (LPL) were detected by reverse transcriptase polymerase chain reaction (RT-PCR). The 50% ethanolic extracts ($100{\mu}g/mL$) of stem and leaf (SALE) and 30% ethanolic extracts (100 g/mL) of whole plant (SAE) from Salvia plebeia R. Br. were significantly attenuated lipid accumulation during adipogenesis in 3T3-L1 cells. Ethyl acetate-soluble fractions ($50{\mu}g/mL$) significantly inhibited lipid droplet accumulation in 3T3-L1 cells. In addition, SALE induced down-regulation of specific adipogenic transcriptional factors (C/$EBP{\alpha}$ and $PPAR{\gamma}$) and target genes (FAS and LPL) during adipogenesis. Salvia plebeia R. Br. may be used as a safe and efficient natural substance to manage obesity.

• 생약학회지
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• 제24권2호
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• pp.131-139
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• 1993

These studies were conducted to investigate the effects of the extracts from Hoelen alba, Alismatis Rhizoma and Atractylodes Rhizoma on the proliferation and differentiation of 3T3-L1 cells. The results were summerized as follows: Hoelen alba and Alismatis Rhizoma extracts inhibited the proliferation of preadipose 3T3-L1 cells. In inductive differentiation, all three extracts inhibited the adipose conversion in 2 days of initial-culture, Atractylodes Rhizoma extract inhibited the adipose conversion in 5 days of final-culture and Hoelen alba and Alismatis Rhizoma inhibited adipose conversion in treatment of whole term of culture. In spontaneous differentiation, Atractylodes Rhizoma extract increased the adipose conversion in 2 days of initial-culture, Hoelen alba and Alismatis Rhizoma increased the adipose conversion in 5 days of final-culture, all three extracts increased adipose conversion in treatment of whole term of culture. The 10% serum of mice treated with each sample did not affect, but the 5% serum of them inhibited the proliferation of 3T3-L1 cells. In inductive differentiation, the 10% serum of them inhibited the adipose conversion in treatment of whole term of culture.

• 한국융합학회논문지
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• 제10권3호
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• pp.127-133
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• 2019

본 연구는 3T3-L1 세포로 하늘타리(Trichosanthes kirilowii Maxim) 뿌리 에탄올 추출물(TKM)의 항비만 활성을 조사하였다. TKM 처리 한 3T3-L1 지방세포의 분화억제를 통한 지방생성 억제에 초점을 두었다. 세포독성을 나타내지 않는 100ug/ml 농도에서 TG 함량을 현저히 억제하고, 세포 초기분화 전사인자 $PPAR{\gamma}$, $C/EBP{\alpha}$, SREBP-1c의 발현 억제, 세포내 에너지 향상성 조절인자 pAMPK, 중성지방산의 합성분해 조절인자 pACC, CPT-1, 지방산 합성 효소(FAS) 발현 억제, 호르몬자극지방분해 효소(HSL) 활성화 등 지방합성 관련인자들의 발현 조절 효능이 있는 것으로 확인되었다. 이상의 결과로 TKM은 지방세포 분화와 지방대사 관련 인자들의 발현을 조절함으로써 지방 생성과 축적 저해 효능을 보여 항비만 융합치료제로의 가능성을 제시하였다.