• Journal of Microbiology and Biotechnology
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• 제22권6호
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• pp.806-813
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• 2012

Adipocyte differentiation is strongly associated with obesity, which causes metabolic disorders. In this study, we investigated the inhibitory effects of widdrol on 3T3-L1 preadipocyte growth and differentiation. Widdrol decreased lipid droplet accumulation and down-regulated adipogenic transcription factors such as C/$EBP{\alpha}$, C/$EBP{\beta}$, and $PPAR{\gamma}$. Widdrol blocked preadipocyte proliferation and differentiation through the inhibition of mitotic clonal expansion, which was accompanied by the failure of degradation of p21, a cyclin-dependent kinase inhibitor. Cell-cycle analysis clearly indicated that widdrol actively induces cell-cycle arrest at the G1-S phage transition, causing cells to remain in the preadipocyte state. Moreover, widdrol increased p21 expression and inhibited Rb phosphorylation in preadipocyte incubated in a hormone medium. Therefore, these findings clearly suggest that widdrol blocks preadipocyte growth and differentiation through the inhibition of mitotic clonal expansion by p21-and Rb-dependent G1 arrest and can be developed as a potent anti-adipogenic agent for reducing obesity.

• International Journal of Industrial Entomology and Biomaterials
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• 제21권2호
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• pp.169-174
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• 2010

Hydrolysate silk fibroin (HSF) is a fibrous protein composed of parallel $\beta$-structures and is made from pure silk elements including 18 amino acids, with glycine, alanine, and serine comprising of over 80% of the amino acids. Numerous studies have documented a range of effects of HSF, including moisturizing, antioxidant activity, nervous system disorders, and many more. We investigated whether HSF has anti-obesity effects in vitro. The effects of HSF inhibition on lipid accumulation and acceleration of lipid degradation in 3T3-L1 cells were studied. Treatment of 3T3-L1 cells with HSF caused significant inhibition of cell viability, an increase in glycerol release, and a decreased in adipocyte differentiation. Moreover HSF stimulated downregulated of adipogenic enzyme expressions (PPAR${\gamma}$ and C/EBP${\alpha}$) and up-regulated of fatty oxidation enzyme expressions (CPT-1 and UCP-2). Based on these results, hydrolysate silk fibroin can be suggested as a potential therapeutic substance as part of a prevention or treatment strategy for obesity.

• Journal of Ginseng Research
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• 제41권3호
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• pp.257-267
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• 2017

Background: Heat-processed ginseng, sun ginseng (SG), has been reported to have improved therapeutic properties compared with raw forms, such as increased antidiabetic, anti-inflammatory, and antihyperglycemic effects. The aim of this study was to investigate the antiobesity effects of SG through the suppression of cell differentiation and proliferation of mouse 3T3-L1 preadipocyte cells and the lipid accumulation in Caenorhabditis elegans. Methods: To investigate the effect of SG on adipocyte differentiation, levels of stained intracellular lipid droplets were quantified by measuring the oil red O signal in the lipid extracts of cells on differentiation Day 7. To study the effect of SG on fat accumulation in C. elegans, L4 stage worms were cultured on an Escherichia coli OP50 diet supplemented with $10{\mu}g/mL$ of SG, followed by Nile red staining. To determine the effect of SG on gene expression of lipid and glucose metabolism-regulation molecules, messenger RNA (mRNA) levels of genes were analyzed by real-time reverse transcription-polymerase chain reaction analysis. In addition, the phosphorylation of Akt was examined by Western blotting. Results: SG suppressed the differentiation of 3T3-L1 cells stimulated by a mixture of 3-isobutyl-1-methylxanthine, dexamethasone, and insulin (MDI), and inhibited the proliferation of adipocytes during differentiation. Treatment of C. elegans with SG showed reductions in lipid accumulation by Nile red staining, thus directly demonstrating an antiobesity effect for SG. Furthermore, SG treatment down-regulated mRNA and protein expression levels of peroxisome proliferator-activated receptor subtype ${\gamma}$ ($PPAR{\gamma}$) and CCAAT/enhancer-binding protein-alpha ($C/EBP{\alpha}$) and decreased the mRNA level of sterol regulatory element-binding protein 1c in MDI-treated adipocytes in a dose-dependent manner. In differentiated 3T3-L1 cells, mRNA expression levels of lipid metabolism-regulating factors, such as amplifying mouse fatty acid-binding protein 2, leptin, lipoprotein lipase, fatty acid transporter protein 1, fatty acid synthase, and 3-hydroxy-3-methylglutaryl coenzyme A reductase, were increased, whereas that of the lipolytic enzyme carnitine palmitoyltransferase-1 was decreased. Our data demonstrate that SG inversely regulated the expression of these genes in differentiated adipocytes. SG induced increases in the mRNA expression of glycolytic enzymes such as glucokinase and pyruvate kinase, and a decrease in the mRNA level of the glycogenic enzyme phosphoenol pyruvate carboxylase. In addition, mRNA levels of the glucose transporters GLUT1, GLUT4, and insulin receptor substrate-1 were elevated by MDI stimulation, whereas SG dose-dependently inhibited the expression of these genes in differentiated adipocytes. SG also inhibited the phosphorylation of Akt (Ser473) at an early phase of MDI stimulation. Intracellular nitric oxide (NO) production and endothelial nitric oxide synthase mRNA levels were markedly decreased by MDI stimulation and recovered by SG treatment of adipocytes. Conclusion: Our results suggest that SG effectively inhibits adipocyte proliferation and differentiation through the downregulation of $PPAR{\gamma}$ and $C/EBP{\alpha}$, by suppressing Akt (Ser473) phosphorylation and enhancing NO production. These results provide strong evidence to support the development of SG for antiobesity treatment.

• 한국미생물·생명공학회지
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• 제40권1호
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• pp.50-56
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• 2012

Wnt/${\beta}$-catenin 신호전달체계는 세포의 분화와 증식, 기관의 발생과 조절을 담당하는 중요한 세포내 신호전달체계이다. 발생과정에서 Wnt/${\beta}$-catenin 신호전달체계의 작용이 지방세포로의 분화를 억제하고 조골세포와 신경세포로의 분화는 촉진한다는 많은 연구들이 보고되어 있으며, 현재 Wnt/${\beta}$-catenin 신호전달체계의 조절을 통한 여러 질병의 치료와 예방에 대한 관심이 대두되고 있다. 본 연구에서는 세포를 기반으로 한 초고속 저분자 스크리닝 시스템을 이용하여 Wnt의 상승제인 silybin을 발굴하였다. silybin은 Wnt가 존재 않을 경우에는 ${\beta}$-catenin 단백질의 수준에 영향을 미치지 않지만 Wnt가 존재할 경우, mRNA 발현양의 변화 없이 세포질내의 ${\beta}$-catenin 단백질의 수준을 증가시킨다. 또한 silybin에 의해 증가된 ${\beta}$-catenin으로 인해 지방세포분화에 중요한 전사인자라고 알려진 PPAR-${\gamma}$와 C/EBP-${\alpha}$의 발현을 억제한다. 따라서 이 연구에서는 silybin이 세포질내 ${\beta}$-catenin 단백질의 수준을 증가시킴으로써 Wnt/${\beta}$-catenin 신호전달체계를 활성한다는 사실을 제시하였다.

• Nutrition Research and Practice
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• 제8권1호
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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.

• KSBB Journal
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• 제24권6호
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• pp.549-555
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• 2009

본 연구에서는 신생혈관형성 제어에 바탕을 둔 비만세포제어 정도를 확인하기 위하여 4가지 지역 천연산물인 전호(Anthrisci radix), 파고지 (Psoraleae semen), 희첨 (Siegesbeckiae herba) 및 산수유 (Corni fructus)를 이용한 지방 축적물 변화 및 기전을 확인하기 위해 3T3-L1 adipocyte를 이용한 Oil Red O 염색 및 western blot을 실시하였다. 그 결과 전호, 파고지, 희첨, 산수유의 세포 독성 이내의 농도 증가에 따라 지방 축적물이 감소됨을 보였다. 또한 western blot을 위해 lipogenesis와 관련된 SREBP-1 및 adipogenesis와 관련된 $PPAR\gamma$와 C/$EBP\alpha$의 신호전달 정도를 확인한 결과 4가지 지역 천연산물의 농도 증가에 따라 단백질의 발현양이 감소됨을 확인하였다. 이는 4가지 지역 천연산물 추출물이 지방분화와 관련된 신호분자를 차단함으로써 지방형성이 억제되었음을 보였다. 따라서 4가지 지역 천연산물인 전호, 파고지, 희첨 및 산수유는 신생혈관형성 억제에 따른 항비만제제로서의 이용 가능함을 시사하였다.

• 한국미생물·생명공학회지
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• 제42권4호
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• pp.354-360
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• 2014

본 연구에서는 토복령(S. china) 메탄올 추출물(SCME)의 항비만 활성을 pancreatic lipase 효소 활성 억제능과 세포 실험계를 이용하여 분석하였다. 그 결과 SCME는 농도 의존적으로 lipase 효소 활성을 유의적으로 억제시켰으며, 3T3-L1 preadipocyte에서 MDI로 유도한 지방세포 분화, 세포 내 지방 축적, TG 함량 등을 농도의존적으로 억제하였다. 이러한 토복령의 지방세포 분화 억제능은 핵심 작용 인자인 $C/EBP{\alpha}$, $C/EBP{\beta}$, 그리고 $PPAR{\gamma}$의 유전자 및 단백질 발현조절에서 기인함을 확인하였다. 또한 지방세포 내 중성지방 또한 토복령 추출물의 처리에 의해 유의적으로 분해되는 것으로 나타났다. 이러한 결과는 토복령이 보유한 pancreatic lipase 활성 저해능, 지방세포 분화 억제능, 지방세포 내 지방 분해능을 통한 항비만 활성을 처음으로 밝혀낸 것이며 추후 계속적인 연구를 통해 활성 물질의 규명이 필요할 것으로 판단된다.

• 한국축산식품학회지
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• 제39권3호
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• pp.430-445
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• 2019

Natural edible waxes mixed with plant oils, containing high levels of unsaturated fatty acids (FAs), are known as oleogels. Oleogels are used for replacing saturated FAs in animal-derived food with unsaturated FAs. However, the health effects of edible waxes are not yet clearly defined. The purpose of this study was to investigate the effect of FAs and natural waxes on the adipogenesis in 3T3-L1 cells. The 3T3-L1 cells were differentiated and treated with FAs and waxes. These FAs [Palmitic acid (PA), Stearic acid (SA), Oleic acid (OA), Linoleic acid (LA), and Alpha-linolenic acid (ALA)] and waxes [beeswax (BW) and carnauba wax (CW)] were prepared at varying concentrations, and cell toxicity, triglyceride accumulation, lipid droplets size, and distribution inside of cells were determined. Adipogenic gene expression including $PPAR{\gamma}$, FASN, $C/EBP{\alpha}$, SREBP-1, and CPT-1 was determined. Results showed that increasing the concentration of FAs and waxes led to a decrease in the adipocyte cells viability and metabolic performance. SA showed the highest level of triglyceride accumulation (p<0.05), whereas ALA showed the lowest (p<0.05). Both BW and CW at 3.0 ppm showed significantly higher lipid accumulation than in the control and other groups (p<0.05). ALA had significantly downregulated adipogenic gene expression levels, excluding those of CPT-1, compared to the other treatment groups (p<0.05). Moreover, BW demonstrated similar adipogenic gene expression levels as ALA compared to CW. Consequently, ALA and BW may have health benefits by reducing adipogenesis and can be used in processed meat.

• 대한의생명과학회지
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• 제23권3호
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• pp.261-271
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• 2017

It has been suggested that ginseng is beneficial for ameliorating the aging males' symptoms, such as weight gain, fatigue, erectile dysfunction, and depression, in elderly men with testosterone deficiency. We thus investigated the effects of Korean red ginseng (Panax ginseng C.A. Meyer; Araliaceae) on obesity in a mouse model of testosterone deficiency (castrated C57BL/6J mice). The effects of ginseng extract (GE) and/or testosterone on obesity and adipogenesis in high-fat diet (HFD)-fed castrated C57BL/6J mice and 3T3-L1 adipocytes were examined using in vivo and in vitro approaches. After feeding mice a HFD for 8 weeks, we found that mice also receiving GE and/or testosterone showed decreased body weight, adipose tissue mass, adipocyte size, and hepatic lipid accumulation compared with untreated HFD-fed mice. Expression of adipogenic genes ($PPAR{\gamma}$, $C/EBP{\alpha}$, and aP2) was decreased by GE and/or testosterone in adipose tissues. Consistent with the in vivo data, lipid accumulation and the mRNA expression of adipogenesis genes in 3T3-L1 adipocytes were decreased by GE, ginsenosides, and testosterone. The inhibitory effects of GE (or ginsenosides) were comparable to those of testosterone, and the effects of co-treatment with GE (or ginsenosides) and testosterone were greater than those of testosterone alone in vivo and in vitro. Our results indicate that ginseng may be able to potentiate the inhibitory effects of testosterone on obesity and adipogenesis in HFD-fed castrated mice, providing possible therapeutic implications in men with testosterone deficiency.

• Nutrition Research and Practice
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• 제6권6호
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• pp.499-504
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• 2012

This study attempted to investigate the effects of resveratrol on the differentiation of adipocytes. After cells were treated with various concentrations of resveratrol (0, 10, 20, and 40 ${\mu}mol/L$), adipocyte proliferation, the protein expression of transcription factors, and MMPs' activities were determined. Cell proliferation was inhibited more within 4 days of incubation (P<0.05), and lipid accumulation in adipocyte was significantly inhibited by 93.8%, 92.4% and 91.5%, respectively, after two days of 10, 20, and 40 ${\mu}mol/L$ resveratrol treatment (P<0.05). Six days of incubation with the three resveratrol concentrations caused a significantly decreases of 63%, 59.9%, and 25.1% GPDH activity as a dose-dependent response. The triglyceride concentration also decreased significantly with the increase of resveratrol concentration (P<0.05). The protein expression of CCAAT/enhancer-binding protein (C/$EBP{\beta}$) was decreased significantly by 56% and 30% while $PPAR{\gamma}$ was significantly reduced by 57% and 15% with resveratrol treatments of 20 and 40 ${\mu}mol/L$, respectively (P<0.05). The protein expression of C/$EBP{\alpha}$ was decreased by 83%, 74%, and 38% to increased dosage levels, with significance determined for this decrease from 20 ${\mu}mol/L$ of resveratrol. The protein expression of fatty acid binding protein (FABP4) was decreased significantly by 88%, 72%, and 46% with the increase of resveratrol concentration. The activity of MMP-2 was decreased significantly by 84%, 70%, and 63% while MMP-9 activity was decreased significantly by 74%, 62%, and 39% with the increased resveratrol concentrations of 10, 20, and 40 ${\mu}mol/L$, respectively (P<0.05).