• Journal of Nutrition and Health
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• v.39 no.8
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• pp.742-747
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• 2006

This study was performed to investigate the lipolytic effects of Portulaca oleracea L. extract in 3T3-L1 adipocytes. The Portulaca oleracea L. was extracted with extrusion method using twin-screw extruder under $58{\sim}60rpm$ screw speed, $4{\sim}5kg/hr$ feed rate, $140^{\circ}C$ extrusion temperature. The lipolytic action of Portulaca oleracea L. extract was estimated by measuring the amount of glycerol and free fatty acids (FFA) released from 3T3-L1 adipocytes and by measuring the cellular lipid content in 3T3-L1 adipocytes. The hormone sensitive lipase (HSL) mRNA level was analyzed using quantitative real-time PCR. The Portulaca oleracea L. extract at 1 to $100{\mu}g/ml$ suppressed lipid accumulation. The release of glycerol and FFA into the medium, and the mRNA level of HSL were significantly increased by the addition of Portulaca oleracea L. extract at dose-dependent manner. In conclusion, the Portulaca oleracea L. extract was suggested to have the lipolytic effect through release of lipolytic products (FFA and glycerol) of triacylglyceride to the culture medium and suppression of lipid accumulation via up-regulation of HSL gene expression in 3T3-L1 adipocytes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.5
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• pp.372-379
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• 2004

This study evaluated polymanuronates on the differentiation of 3T3-L1 adipocytes. Polymannuronates increased glucose utilization and reduced the accumulation of triglycerides in the cells. The differentiation showed the same results as Oil red O staining. Also, the polymannuronates inhibited GPDH activity as a result of the restrained adipogenesis promotion process in 3T3-L1 adipocytes. The addition of the differentiation promotion factor to 3T3-L1 promoted the differentiation of adipocytes and increased the expression of the leptin level. However the addition of polymannuronates inhibited differentiation of adipocytes and the leptin secretion level in cells by checking the leptin protein level in the culture media. As well as this, it also inhibited the transcriptional mechanism and leptin mRNA expression. These results suggest that the addition of polymannuronates improves the physiological function of 3T3-L1 cells by reducing the accumulation of triglyceride and GPDH activity, and the repressing expression of leptin at a molecular level.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.2
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• pp.266-271
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• 2010

Obesity occurred by energy imbalance, is increasing regardless of race, sex, age, and related to the metabolic syndrome, diabetes and cardiovascular disease. Since adipose tissue plays a critical role in regulating energy homeostasis, understanding of adipogenesis pathway and finding of regulatory mechanism for adipogenesis can be helpful to manage obesity as well as obesity-related diseases. In this study, to investigate the effects of Chestnut Inner Shell(CIS) extract on the adipogenesis in 3T3-L1 preadipocytes, 3T3-L1 preadipocytes were differentiated with adipogenic reagents for 9 days in the absence or presence of CIS extract ranging from 10 - 100 ${\mu}g/m{\ell}$. The effect of CIS extract on 3T3-L1 differentiation was examined by measuring intracelluar lipid droplet and triglyceride contents. CIS extract remarkably inhibited lipid accumulation(about 45% inhibition at 100 ${\mu}g/m{\ell}$ of CIS extract) and slightly decreased triglyceride contents(about 15% decrease at 100 ${\mu}g/m{\ell}$ of CIS extract) in 3T3-L1 preadipocytes at the concentration showing no cytotoxicity. These results demonstrated that CIS extract significantly inhibit adipogenesis and can be used for the regulation of obesity.

• Applied Biological Chemistry
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• v.45 no.1
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• pp.42-46
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• 2002

Effects of the water extract from Kalopanax pictus NAKAI on insulin-like action and glucose uptake in 3T3-L1 cells were investigated. The bark of K. pictus NAKAI was treated with hot water and the extract was freeze-dried. Total extract of K. pictus NAKAI was fractionated into 6 fractions with increasing gradients from 0 to 100% MeOH on Amberlite XDA-4. Treatment of 3T3-L1 fibroblasts with 1 ${\mu}g/ml$ and 10 ${\mu}g/ml$ of K. pictus NAKAI total extracts significantly increased the differentiation of the cells. When co-treated with inducers such a dexamethasone, 1-methyl-3-isobutylxanthine and insulin, the differentiation was increased at 1 ${\mu}g/ml$ of total extract, but not at 10 ${\mu}g/ml$. In 3T3-L1 adipocytes, glucose uptake was increased by 3.3 times with addition of 0.3 and 3 ${\mu}g/ml$ of Fr. 1 (0-10% MeOH) and Fr. 3 (30% MeOH) at 3 ng/ml insulin. In conclusion, K. pictus NAKAI contains such compounds that play a role of insulin-like action and insulin sensitizer.

• Journal of Life Science
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• v.32 no.2
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• pp.86-93
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• 2022

Lupeol is a type of pentacyclic triterpene and has been reported to have pharmacological activities against various diseases; however, the effect of lupeol on glucose absorption has not been elucidated yet. This study aimed to investigate the effect of lupeol on glucose uptake in 3T3-L1 adipocytes. Lupeol significantly facilitated glucose uptake by translocating glucose transporter type 4 (GLUT4) to the plasma membrane of the 3T3-L1 adipocytes, which was related to activation of the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) and 5 'adenosine monophosphate-activated protein kinase (AMPK) pathways. In the PI3K/AKT pathway, lupeol stimulates the phosphorylation of insulin receptor substrate 1 (IRS-1), which activates PI3K. Its activation by lupeol promotes the phosphorylation of AKT, but not the atypical protein kinase C isoforms ζ and λ. Lupeol also promoted the phosphorylation of AMPK. The activation of AMPK increased the expressions of the plasma membrane GLUT4 and the intracellular glucose uptake. The increase in the glucose uptake by lupeol was suppressed by wortmannin (PI3K inhibitor) and compound C (AMPK inhibitor) in the 3T3-L1 adipocytes. The results indicate that lupeol can facilitate glucose uptake by increasing insulin sensitivity through the stimulation of the expression of plasma membrane glucose transporter type 4 via the PI3K/AKT and AMPK pathways in the 3T3-L1 adipocytes.

• Ocean and Polar Research
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• v.44 no.1
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• pp.61-67
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• 2022

In this study, in order to evaluate the anti-obesity effect of sargassum horneri extract, the effects of the extract on lipase activity and preadipocyte differentiation in 3T3-L1 cells were investigated. S. horneri extract between 0.0 and 1.0 mg/mL showed no cytotoxicity and inhibited lipase activity by 68.1%. When S. horneri extract was utilized at levels of 0.25, 0.5, and 1.0 mg/mL in 3T3-L1 cells, preadipocytes differentiation decreased by 11.4, 19.7, and 25.6%, respectively, showing anti-obesity effects. In addition, after treatment with 1.0 mg/mL S. horneri extract, the mRNA expression levels of sterol regulatory element binding proteins-1c (SREBP-1c), peroxisome proliferator activated receptor-γ (PPAR-γ), CCAAT enhancer binding protein-α (CEBP-α), fatty acid synthase (FAS), and stearoyl-CoA desaturase1 (SCD1) in 3T3-L1 cells were significantly decreased (p < 0.05) by 65.2, 54.9, 50.0, 33.8, and 33.8% respectively. These results showed that S. horneri extract suppresses lipase activity and prophylactic preadipocyte differentiation in 3T3-L1, and thus can be used as an anti-obesity agent in functional foods and medicines.

• The Korea Journal of Herbology
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• v.31 no.5
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• pp.47-53
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• 2016

Objectives : Mori Follium (Morus alba L. leaf) has been cultivated in many Asian countries. Especially, mulberry leaf has been used as an anti-diabetic remedy in oriental medicine. However, anti-obesity effect of mulberry has not been unknown. In this study, our objectives of study is to investigate the anti-adipogenic effect of mulberry water extract (MLE) and to reveal potential molecular anti-obesity mechanism in 3T3-L1 adipocytes differentiation model.Methods : The cytotoxicity of MLE in 3T3-L1 was examined by MTT assay. Anti-adipogenic effect of MLE was evaluated by Oil Red O (ORO) staining. To elucidate the molecular mechanism, inhibitor assay was employed. The mRNA expression levels of adipogenic transcriptional factors such as PPARγ and fatty acid synthase (FAS) were analyzed by reverse transcription-polymer chain reaction (RT-PCR) analysis.Results : The MLE treatment for 24 h did not affect to the 3T3-L1 cells at concentrations of 1, 10, 100, 200, 400, 800 and 1,000 ㎍/㎖. Thus, non-toxic concentration rages of MLE were used during adipogenesis period (day -2 to 7). Intracellular lipid accumulation in MLE-treated 3T3-L1 adipocytes (day 6) were quantitatively evaluated by ORO staining. The MLE treatment significantly and dose-dependently suppressed 3T3-L1 adipogenesis by 60.42%, 38.24%, and 5.97% at 10, 100, and 200 ㎍/㎖, respectively. In addition, our inhibitor assay and RT-PCR analysis revealed that the MLE-inhibited 3T3-L1 adipogenesis through inhibition of PPARγ mediated by Wnt/β-catenin signaling pathway.Conclusions : In conclusion, these findings indicate that the MLE could be used in prevent and/or treatment of obesity-related diseases.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.1
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• pp.86-92
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• 2007

Hibiscus sabdariffa L., a tropical beverage material, is used commonly as in folk medicine against hypertension, pyrexia, inflammation, liver disorders, and obesity. However, the mechanism by which Hibiscus sabdariffa L. modulates adipogenic differentiation is remained to be elusive. This report was designed to investigate the inhibitory effect of Hibiscus extract on insulin signaling pathway during adipocyte differentiation in 3T3-L1 preadipocytes. 3T3-L1 preadipocytes were differentiated with isobutylmethylxanthine, dexamethasone, and insulin (MDI) and followed by the addition of Hibiscus extract. Treatment with Hibiscus resulted in a decrease of lipid droplet accumulation, which was suppressed by PI-3 kinase inhibitor wortmannin in 3T3-L1 preadipocytes. Also, Hibiscus extract markedly attenuated the mRNA expression of adipogenic transcriptional factor PPAR${\gamma}$ and adipogenic hormon Leptin during adipogenesis. However, it did not affect the expression of adiponectin in 3T3-L1 preadipocytes differentiated with MDI mixture. Furthermore, Adipogenic differentiation by MDI mixture increased the phosphorylation and expression of PI3-Kinase and Akt in 3T3 preadipocytes, which was markedly suppressed by Hibiscus extract treatment. Taken together, our results suggest that Hibiscus extract suppressed the adipogenic differentiation of 3T3 preadipocytes through activation of PI3-Kinase and Akt signaling pathway.

• Nutrition Research and Practice
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• v.8 no.1
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• pp.33-39
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• 2014

Obesity occurs when a person's calorie intake exceeds the amount of energy burns, which may lead to pathologic growth of adipocytes and the accumulation of fat in the tissues. In this study, the effect and mechanism of pear pomace extracts on 3T3-L1 adipocyte differentiation and apoptosis of mature adipocytes were investigated. The effects of pear pomace extract on cell viability and the anti-adipogenic and proapoptotic effects were investigated via MTT assay, Oil red O staining, western blot analysis and apoptosis assay. 3T3-L1 preadipocytes were stimulated with DMEM containing 10% FBS, 0.5 mM 3-isobutyl-1-methylxanthine (IBMX), $5{\mu}g/ml$ insulin and $1{\mu}M$ dexamethasone for differentiation to adipocytes. 3T3-L1 cells were cultured with PBS or water extract of pear pomace. Water extract of pear pomace effectively inhibited lipid accumulations and expressions of PPAR-${\gamma}$ and $C/EBP{\alpha}$ in 3T3-L1 cells. It also increased expression of p-AMPK and decreased the expression of SREBP-1c and FAS in 3T3-L1 cells. The induction of apoptosis was observed in 3T3-L1 cells treated with pear pomace. These results indicate that pear pomace water extract inhibits adipogenesis and induces apoptosis of adipocytes and thus can be used as a potential therapeutic substance as part of prevention or treatment strategy for obesity.

• Journal of Life Science
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• v.31 no.1
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• pp.1-9
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• 2021

Brown seaweeds have been shown to decrease blood glucose levels and improve insulin sensitivity previously. In this study, we investigated the effect of fucoidan, a complex polysaccharide derived from brown seaweeds, on glucose uptake to improve insulin resistance, and examined its mechanism of action in 3T3-L1 adipocytes. We observed that fucoidan significantly increased glucose uptake and it was related to an increased expression of plasma membrane-glucose transporter 4 (PM-GLUT4) in 3T3-L1 adipocytes. Fucoidan treatment increased the activation of phosphatidylinositol-3-kinase (PI3K) and the phosphorylation of insulin receptor substrate 1 (IRS1tyr) compared with that of the control cells. Fucoidan also promoted the phosphorylation of Akt and protein kinase C (PKC)-λ/ζ compared to that of the control cells. Moreover, fucoidan significantly upregulated acetyl-CoA-carboxylase (ACC) and adenosine monophosphate - activated protein kinase (AMPK) phosphorylation. As a result, translocation of GLUT4 was significantly enhanced in 3T3-L1 adipocytes, which significantly promoted glucose uptake via the PI3K/AMPK pathways. The elevation of glucose uptake by fucoidan was blocked by inhibitor of PI3K and inhibitor of AMPK in 3T3-L1 adipocytes. These findings indicate that fucoidan might ameliorate glucose uptake through GLUT4 translocation to the plasma membrane by activating the PI3K/Akt and AMPK pathways in 3T3-L1 adipocytes. Fucoidan is thought to be of high material value to diabetes treatments and functional foods.