• Journal of Life Science
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• v.22 no.10
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• pp.1399-1406
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• 2012

The present study was conducted to evaluate the effects of various extracts of Hizikia fusiforme on the anti-obesity effects in 3T3-L1 preadipocytes. We used H. fusiforme extracts from ethanol (EEHF), dichloromethane (CFHF), ethyl acetate (EAFHF), butanol (BFHF), and water (WFHF). Treatment with these extracts significantly suppressed terminal differentiation of 3T3-L1 preadipocytes in a dose-dependent manner as confirmed by a decrease in lipid droplet content through Oil Red O staining; this effect was higher in WFHF than in other extracts. The concentrations of cellular triglyceride were also reduced in 3T3-L1 cells by exposure with these extracts, especially when compared with the controls. Treatment with 200 ${\mu}g/ml$ of WFHF and CFHF caused approximately 42.6% and 23.7% reduction, respectively. In addition, the extracts of H. fusiforme significantly reduced the expression levels of key pro-adipogenic transcription factors, including peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$) and CCAAT/enhancer binding proteins ${\alpha}$ (C/$EBP{\alpha}$) and C/$EBP{\beta}$ as compared with controls. Accordingly, our data indicated that WFHF has a preeminent effect on inhibition of adipocyte differentiation among various extracts, and H. fusiforme extracts may be an ideal candidate for obesity relief.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.05a
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• pp.72-72
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• 2003

Induction of glutathione S-transferases is associated with cancer chemoprevention. We reported that PD98059, an MKK1 inhibitor, induces glutathione Stransferase A2 (rGSTA2). This report comparatively examines the role of CCAAT/enhancer binding protein (C/EBP) and Nrf-2 in the induction of rGSTA2 by PD98059. PD98059 at the concentrations effective for the inhibition of MKKI increased the rGSTA2 protein and mRNA levels in H4IIE cells. (omitted)

• Journal of Life Science
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• v.26 no.12
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• pp.1367-1375
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• 2016

Cilostazol is known to be a selective inhibitor of phosphodiesterase III and is generally used to treat stroke. Our previous findings showed that cilostazol enhanced capillary density through angiogenesis after focal cerebral ischemia. Angiogenesis is an important physiological process for promoting revascularization to overcome tissue ischemia. It is a multistep process consisting of endothelial cell proliferation, migration, and tubular structure formation. Here, we examined the modulatory effect of cilostazol at each step of the angiogenic mechanism by using human brain microvascular endothelial cells (HBMECs). We found that cilostazol increased the migration of HBMECs in a dose-dependent manner. However, it did not enhance HBMEC proliferation and capillary-like tube formation. We used a cDNA microarray to analyze the mechanisms of cilostazol in cell migration. We picked five candidate genes that were potentially related to cell migration, and we confirmed the gene expression levels by real-time PCR. The genes phosphoserine aminotransferase 1 (PSAT1) and CCAAT/enhancer binding protein ${\beta}$ ($C/EBP{\beta}$) were up-regulated. The genes tissue factor pathway inhibitor 2 (TFPI2), retinoic acid receptor responder 1 (RARRES1), and RARRES3 were down-regulated. Our observations suggest that cilostazol can promote angiogenesis by promoting endothelial migration. Understanding the cilostazol-modulated regulatory mechanisms in brain endothelial cells may help stimulate blood vessel formation for the treatment of ischemic diseases.

• 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.

• IMMUNE NETWORK
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• v.20 no.5
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• pp.42.1-42.10
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• 2020

Long-lasting post-switched plasma cells (PCs) arise mainly from germinal center (GC) reactions, but little is known about the mechanism by which GC B cells differentiate into PCs. Based on our observation that the expression of the transcription factor CCAAT/enhancer binding protein β (C/EPBβ) is associated with the emergence of post-switched PCs, we enquired whether a cell-autonomous function of C/EPBβ is involved in the program for PC development. To address this, we generated C/EPBβ-deficient mice in which the Cebpb locus was specifically deleted in B cells after transcription of the Ig γ1 constant gene segment (Cγ1). In response to in vitro stimulation, B cells from these Cebpb^fl/flCγ1^Cre/+ mice had defects in the induction of B lymphocyte-induced maturation protein 1 (Blimp1) and the formation of IgG1⁺ PCs, but not in proliferation and survival. At steady state, the Cebpb^fl/flCγ1^Cre/+ mice had reduced serum IgG1 titers but normal IgG2c and IgM titers. Moreover, upon immunization with T-dependent Ag, the mice produced reduced levels of Ag-specific IgG1 Ab, and were defective in the production of Ag-specific IgG1 Ab-secreting cells. These results suggest that a cell-autonomous function of C/EPBβ is crucial for differentiation of post-switched GC B cells into PCs through a Blimp1-dependent pathway.

• Journal of Nutrition and Health
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• v.48 no.1
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• pp.9-18
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• 2015

Purpose: Poncirus trifoliata has been reported to have anti-inflammatory, antioxidant, and immune activities. However, its anti-obesity activity and the mechanism by which the water extract of dried, immature fruit of Poncirus trifoliata (PF-W) acts are not clear. This study suggests a potential mechanism associated with the anti-obesity activity of PF-W. Methods: We measured the effect of PF-W on lipoprotein lipase (LPL) regulation using enzyme-linked immunosorbent assay (ELISA) and an activity assay. The LPL regulation mechanism was examined by reverse transcription polymerase chain reaction (RT-PCR) to measure the mRNA expression of biomarkers related to protein transport and by western blot for analysis of the protein expression of the transcription factor CCAAT-enhancer-binding protein ($C/EBP{\beta}$). Results: The total polyphenol and flavonoid content of PF-W was $52.15{\pm}4.02$ and $6.56{\pm}0.47mg/g$, respectively. PF-W treatment decreased LPL content in media to $58{\pm}5%$ of that in control adipocyte media, and increased LPL content to $117{\pm}3.5%$ of that in control adipocytes, but did not affect the mRNA expression of LPL. PF-W also increased the mRNA expression of sortilin-related receptor (SorLA), a receptor that induces endocytosis and intracellular trafficking of LPL, in a concentration- and time-dependent manner. Finally, cell fractionation revealed that PF-W treatment induced the expression of $C/EBP{\beta}$, a SorLA transcription factor, in the nuclei of 3T3-L1 adipocytes. Conclusion: The LPL secretion and activity assay showed PF-W to be an LPL secretion inhibitor, and these results suggest the potential mechanism of PF-W involving inhibition of LPL secretion through $C/EBP{\beta}$-mediated induction of SorLA expression.

• BMB Reports
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• v.42 no.6
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• pp.338-343
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• 2009

The Wnt/$\beta$-catenin signaling pathway alters adipocyte differentiation by inhibiting adipogenic gene expression. $\beta$-catenin plays a central role in the Wnt/$\beta$-catenin signaling pathway. In this study, we revealed that tumour necrosis factor-$\alpha$ (TNF-$\alpha$), a potential negative regulator of adipocyte differentiation, inhibits porcine adipogenesis through activation of the Wnt/$\beta$-catenin signaling pathway. Under the optimal concentration of TNF-$\alpha$, the intracellular $\beta$-catenin protein was stabilized. Thus, the intracellular lipid accumulation of porcine preadipocyte was suppressed and the expression of important adipocyte marker genes, including peroxisome proliferator-activated receptor-$\gamma$ (PPAR$\gamma$) and CCAAT/enhancer binding protein-$\alpha$ (C/EBP$\alpha$), were inhibited. However, a loss of $\beta$-catenin in porcine preadipocytes enhanced the adipogenic differentiation and attenuated TNF-$\alpha$ induced anti-adipogenesis. Taken together, this study indicated that TNF-$\alpha$ inhibits adipogenesis through stabilization of $\beta$-catenin protein in porcine preadipocytes.

• Journal of Life Science
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• v.21 no.9
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• pp.1346-1353
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• 2011

Sophora tonkinensis Gapnep has been used as a traditional herbal medicine in oriental regions since ancient times. In this study, the effect and mechanism of the MeOH extract of Sophora tonkinensis Gapnep (STME) on adipocite differentiation and adipogenesis in 3T3-L1 preadipocites were investigated. Treatment with STME in the concentration range of 0-200 ${\mu}g$/ml significantly inhibited the differentiation of 3T3-L1 preadipocites in a dose-dependent manner, as determined by a decrease in intracellular lipid droplets and lipid contents measured by Oil Red O staining. In association with the inhibitory effect of lipid accumulation, the expressions of the proteins concerned with adipogenesis in 3T3-L1 preadipocites were also investigated. Treatment with STME reduced the expressions of peroxisome proliferator-activated receptor ${\gamma}$ (PPAR${\gamma}$), cytidine-cytidine-adenosine-adenosine-thymine (CCAAT)/enhancer-binding proteins ${\alpha}$ and ${\beta}$ (C/EBP${\alpha}$ and C/EBP${\beta}$) and sterol regulatory element binding protein (SREBP), which are adipocyte specific markers. In flow cytometry analysis, the inhibitory effect of differentiation was caused by G1 arrest and following mitotic clonal expansion cease. Therefore, we also investigated the alteration of G1 phase arrest-related proteins. As a result, the expression of p21 protein was significantly increased, while the expressions of Cdk2, E2F-1 and phospho-Rb were reduced in a dose-dependent manner in STME treated 3T3-L1 cells. According to these results, STME might inhibit differentiation through G1 arrest in 3T3-L1 preadipocytes adipogenesis, and further studies, which are in progress, have to be completed to identify the active compounds.

• Nutrition Research and Practice
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• v.6 no.6
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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).

• Journal of Life Science
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• v.22 no.12
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• pp.1688-1696
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• 2012

Oenanthe javanica has been used as a food source and also in traditional folk medicine for its detoxifying properties and anti-microbial effects since ancient times. In this study, we evaluated the effect and mechanism of O. javanica seed methanol extract (OJSE) on adipocyte differentiation by 3T3-L1 preadipocytes. Under non-toxic conditions, OJSE treatment resulted in a dose-dependent inhibition of lipid droplet generation and triglyceride accumulation by suppressing adipocyte differentiation, which are associated with the decreased expression of key proadipogenic transcription factors including CCAAR/enhancer binding protein ${\alpha}$, ${\beta}$ ($C/EBP{\alpha}$, $C/EBP{\beta}$) and peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$). OJSE also significantly inhibited proliferation and differentiation of 3T3-L1 preadipocytes through G1-phase arrest, indicating that OJSE blocked mitotic clonal expansion during adipocyte differentiation. Investigation of the alteration of G1 phase arrest-related proteins indicated a dose-dependent increase in the expression of p21 and reduction in expression of cyclin E, Cdk2, E2F-1 and phospho-Rb by OSJE. Taken together, these results suggest that OJSE inhibits adipocyte differentiation by blocking the mitotic clonal expansion, which is accompanied by preadipocyte cell cycle arrest.