• The Korean Journal of Physiology and Pharmacology
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• v.20 no.6
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• pp.649-655
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• 2016

TonEBP belongs to the Rel family of transcription factors and plays important roles in inflammation as well as kidney homeostasis. Recent studies suggest that TonEBP expression is also involved in differentiation of several cell types such as myocytes, chondrocytes, and osteocytes. In this study, we investigated the roles of TonEBP during adipocyte differentiation in 3T3-L1 cells. TonEBP mRNA and protein expression was dramatically reduced during adipocyte differentiation. Sustained expression of TonEBP using an adenovirus suppressed the formation of lipid droplets as well as the expression of FABP4, a marker of differentiated adipocytes. TonEBP also inhibited the expression of $PPAR{\gamma}$, a known master regulator of adipocytes. RNAi-mediated knock down of TonEBP promoted adipocyte differentiation. However, overexpression of TonEBP did not affect adipogenesis after the initiation of differentiation. Furthermore, TonEBP expression suppressed mitotic clonal expansion and insulin signaling, which are required early for adipocyte differentiation of 3T3-L1 cells. These results suggest that TonEBP may be an important regulatory factor in the early phase of adipocyte differentiation.

• Journal of Animal Science and Technology
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• v.47 no.6
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• pp.913-918
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• 2005

The development of marbling in cattle is closely associated with an increase in adipocyte size and number within muscle. The adipose precursor cells have the capacity to differentiate into adipocytes within the muscle during the formation of marbling. In this studies, we established the cell culture system for differentiation of intramuscular preadipocyte isolated from the sirloin of Hanwoo aged 12 months. The intramuscular preadipocyte cells exhibited a fibroblastic appearance and differentiated into adipocytes by treating confluent cells with differentiation medium containing insulin, dexamethasone, and troglitazone. When intramuscular preadipocyte cells were differentiated at 18 day, the triglyceride concentration was higher than control cells. Moreover, the thiazolidinedione treatment increased adipogenesis. RT-PCR analysis confirmed the significant expression of PPARγ mRNA during adipocyte differentiation. In conclution, our culture system used in this study allowed intramuscular preadipocyte cells to differentiated into adipocytes and intramuscular preadipocyte cells may be useful in the further study of differentiation mechanism of adipocytes in Hanwoo.

• Journal of Life Science
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• v.17 no.1 s.81
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• pp.56-63
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• 2007

Insulin stimulates the fusion of intracellular vesicles containing glucose transporter 4 (GLUT4) with plasma membrane in adipocytes and muscle cells. Here we show that adipocyte differentiation results in enhanced insulin sensitivity of glucose uptake. On the other hand, glucose uptake in response to platelet-derived growth factor (PDGF) stimulation was markedly reduced by adipocyte differentiation. Expression level of insulin receptor and caveolin-1 was dramatically increased during adipocyte differentiation. Adipocyte differentiation caused :ilightly enhanced activation of acutely transforming retrovirus AKT8 in rodent T cell lymphoma (Akt) by insulin stimulation. However, activation of Akt by PDGF stimulation was largely reduced. Activation of ERK was not detected in both fibroblasts and adipocytes after stimulation with insulin. PDGF-dependent activation of ERK was reduced by adipocyte differentiation. Insulin-dependent glucose uptake was abrogated by LY294002, a phosphatidylinositol 3-kinase (PI3K) inhibitor, in both fibroblasts and adipocytes. Also disassembly of caveolae structure by $methyl-\beta-cyclodextrin$ caused impairment of Akt activation and glucose uptake. Finally, insulin receptor, Akt, SH2-domain-containing inositol 5-phosphatase 2 (SHIP2), and regulatory subunit of PI3K are localized at lipid raft domain and the translocation was facilitated upon insulin stimulation. Given these results, we suggest that lipid raft provide proper site for insulin action for glucose uptake.

• BMB Reports
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• v.46 no.12
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• pp.582-587
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• 2013

Adipocyte differentiation is a complex developmental process forming adipocytes from various precursor cells. The murine 3T3-L1 preadipocyte cell line has been most frequently used in the studies of adipocyte differentiation. Differentiation of 3T3-L1 preadipocytes includes a medium containing fetal bovine serum (FBS) with hormonal induction. In this study, we observed that differentiation medium containing adult bovine serum (ABS) instead of FBS did not support differentiation of preadipocytes. Impaired adipocyte differentiation was due to the presence of a serum protein factor in ABS that suppresses differentiation of preadipocytes. Using a proteomic analysis, alpha-2-macroglobulin and paraoxonase/arylesterase 1, which were previously shown to suppress differentiation of preadipocytes, were identified as anti-adipogenic proteins. Although their functional mechanisms have not yet been elucidated, the anti-adipogenic effects of these proteins are discussed.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.3
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• pp.288-295
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• 2014

Bojungchiseub-tang (BJCST) has been used in symptoms and signs of edema, dampness-phlegm, kidney failure, and so on. BJCST is also expected to have strong anti-obesity activities. However, little is known about the mechanisms of its inhibitory effects on adipocyte differentiation and adipogenesis. In the present study, we examined the effects and mechanism of BJCST on transcription factors and adipogenic genes of 3T3-L1 preadipocytes to understand its inhibitory effects on adipocyte differentiation and adipogenesis. Our results showed that BJCST significantly inhibited differentiation and adipogenesis of 3T3-L1 preadipocytes in a dose-dependent manner. To elucidate the mechanism of the effects of BJCST on lowering lipid content in 3T3-L1 adipocytes, we examined whether BJCST modulate the expressions of transcription factors to induce adipogenesis and adipogenic genes related to regulate accumulation of lipids. As a result, the expression of steroid regulatory element-binding protein (SREBP)1, cytidine-cytidine-adenosine-adenosine-thymidine (CCAAT)/enhancer binding proteins ${\alpha}$ ($C/EBP{\alpha}$), $C/EBP{\beta}$, $C/EBP{\delta}$, and peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$) genes, which induce the adipose differentiation, liver X receptor $(LXR){\alpha}$ and fatty acid synthase (FAS) genes, which induce lipogenesis and adipose-specific aP2, Adipsin, lipoprotein lipase (LPL), CD36, TGF-${\beta}$, leptin and adiponectin genes, which compose fat formation were decreased. BJCST also reduced the expression of acyl CoA oxidase (ACO) and uncoupling protein (UCP) genes related to lipid oxidation. In conclusion, BJCST could regulate transcript factor related to induction of adipose differentiation and inhibited the accumulation of lipids and expression of adipogenic genes.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.3
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• pp.197-206
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• 2021

Carnosol is a phenolic diterpene phytochemical found in rosemary and sage with reported anti-microbial, anti-oxidant, anti-inflammatory, and anti-carcinogenic activities. This study aimed to investigate the effect of carnosol on the lineage commitment of mouse bone marrow-derived mesenchymal stem cells (mBMSCs) into osteoblasts and adipocytes. Interestingly, carnosol stimulated the early commitment of mBMSCs into osteoblasts in dose-dependent manner as demonstrated by increased levels of alkaline phosphatase activity and Alizarin red staining for matrix mineralization. On the other hand, carnosol significantly suppressed adipogenesis of mBMSCs and downregulated both early and late markers of adipogenesis. Carnosol showed to induce osteogenesis in a mechanism mediated by activating BMP signaling pathway and subsequently upregulating the expression of BMPs downstream osteogenic target genes. In this context, treatment of mBMSCs with LDN-193189, BMPR1 selective inhibitor showed to abolish the stimulatory effect of carnosol on BMP2-induced osteogenesis. In conclusion, our data identified carnosol as a novel osteoanabolic phytochemical that can promote the differentiation of mBMSCs into osteoblasts versus adipocytes by activating BMP-signaling.

• Journal of the Korean Society of Food Culture
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• v.33 no.4
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• pp.337-344
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• 2018

Germinated brown rice (GBR, Orysa sartiva L.) has been reported to have anti-obesity and anti-inflammatory effects. However, the mechanisms underlying these effects in adipocytes are not fully understood. Therefore, this study was conducted to explore the anti-inflammatory mechanisms of GBR on lipopolysaccharide (LPS)-stimulated 3T3-L1 adipocytes. 3T3-L1 adipocytes were pretreated with GBR extracts (0-20 mg/mL) 1 h before LPS stimulation. The mRNA expression of adipokines and Toll-like receptor 4 (TLR4) were measured by RT-PCR. The protein expressions of TLR4-related molecules were detected by western blotting and nuclear factor-${\kappa}B$ ($NF-{\kappa}B$) activation was measured. Our results showed that GBR extract dose-dependently inhibited mRNA expression of LPS-induced tumor necrosis factor-${\alpha}$ ($TNF-{\alpha}$), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1). GBR extract was found to inhibit LPS-induced mRNA expression of TLR4 and protein expression of both myeloid differentiation factor 88 (MyD88) and TNF receptor-associated factor 6 (TRAF6). Furthermore, GBR extract significantly inhibited extracellular receptor-activated kinase (ERK) phosphorylation and $NF-{\kappa}B$ activation. These results suggest that GBR extract has the anti-inflammatory effects on LPS-induced inflammation via inhibition of TLR4 signaling, includingthe ERK and $NF-{\kappa}B$ signaling pathways, in adipocytes.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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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 $C/EBP{\alpha}$.

• Natural Product Sciences
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• v.28 no.4
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• pp.161-167
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• 2022

Obesity is a complex metabolic disorder that increases the risk for type 2 diabetes, hyperlipidemia, hypertension, and atherosclerosis. In this study, we evaluated the anti-obesity effects of Nelumbo nucifera leaf (NL) extract in 3T3-L1 adipocytes and obese db/db mice. NL extract among various parts (leaf, seed, and root) of N. nucifera most effectively reduced adipogenesis via inhibiting CCAAT enhancer binding protein α (C/EBPα) and peroxisome proliferator activated receptor γ (PPARγ) expression in 3T3-L1 adipocytes. The addition of NL extract enhanced the protein expression of uncoupling protein 2 (UCP2) as compared to untreated 3T3-L1 adipocytes. The oral administration of NL extract (100 mg/kg BW) significantly reduced food efficacy ratio, body weight, and face or total cholesterol level in obese db /db mice. Also, administration of NL extract significantly decreased adipocyte size and C/EBPα or PPARγ expression in the adipose tissues as compared with control (obese db/db mice). Therefore, our results suggest that NL extract among various parts of N. nucifera could be used as a functional food ingredient for the prevention and treatment of metabolic diseases including obesity and diabetes.

• Nutrition Research and Practice
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• v.8 no.6
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• pp.613-617
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• 2014

BACKGROUND/OBJECTIVES: Adipogenesis is part of the cell differentiation process in which undifferentiated fibroblasts (pre-adipocytes) become mature adipocytes with the accumulation of lipid droplets and subsequent cell morphological changes. Several transcription factors and food components have been suggested to be involved in adipogenesis. The aim of this study was to determine whether mulberry leaf ethanol extract (MLEE) affects adipogenesis in 3T3-L1 adipocytes. MATERIALS/METHODS: The 3T3-L1 adipocytes were treated with different doses of MLEE for 8 days starting 2 days post-confluence. Cell viability, fat accumulation, and adipogenesis-related factors including CCAAT-enhancer-binding protein alpha ($C/EBP{\alpha}$), peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$), $PPAR{\gamma}$ coactivator 1 alpha (PGC-$1{\alpha}$), fatty acid synthase (FAS), and adiponectin were analyzed. RESULTS: Results showed that MLEE treatments at 10, 25, 50, and $100{\mu}g/ml$ had no effect on cell morphology and viability. Without evident toxicity, all MLEE treated cells had lower fat accumulation compared with control as shown by lower absorbances of Oil Red O stain. MLEE at 50 and $100{\mu}g/ml$ significantly reduced protein levels of $PPAR{\gamma}$, PGC-$1{\alpha}$, FAS, and adiponectin in differentiated adipocytes. Furthermore, protein level of $C/EBP{\alpha}$ was significantly decreased by the treatment of $100{\mu}g/ml$ MLEE. CONCLUSION: These results demonstrate that MLEE treatment has an anti-adipogenic effect in differentiated adipocytes without toxicity, suggesting its potential as an anti-obesity therapeutic.