• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.161-167
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• 2012

To evaluate the anti-obesity effect of Agrimonia pilosa L., this study investigated that ethyl acetate extract from A. pilosa L. (EAAP) suppresses lipid accumulation and inhibits expression of adipogenic marker genes, such as peroxisome proliferator activated receptor ${\gamma}$ (PPAR${\gamma}$), CCAAT-enhancer-binding protein ${\alpha}$ (C/EBP${\alpha}$), glucose transporter 4 (GLUT4), and adiponectin in 3T3-L1 preadipocytes. We demonstrated that EAAP inhibited adipocyte differentiation and expression of PPAR${\gamma}$ and C/EBP${\alpha}$ mRNA levels in a dose-dependent manner. In addition, EAAP reduced the PPAR${\gamma}$ transcriptional activity stimulated by rosiglitazone in HEK 293T cells and decreased the expression of GLUT4 and adiponectin in 3T3-L1 cells. These results suggest that EAAP inhibits preadipocyte differentiation and adipogenesis by blocking of PPAR${\gamma}$ and C/EBP${\alpha}$ gene expression in 3T3-L1 cells.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.2
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• pp.83-88
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• 2011

A large body of evidence has indicated that induction of endogenous antioxidative proteins seems to be a reasonable strategy for delaying the progression of cell injury. In our previous study, cilostazol was found to increase the expression of the antioxidant enzyme heme oxygenase-1 (HO-1) in synovial cells. Thus, the present study was undertaken to examine whether cilostazol is able to counteract tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$)-induced cell death in endothelial cells via the induction of HO-1 expression. We exposed human umbilical vein endothelial cells (HUVECs) to TNF-${\alpha}$ (50 ng/ml), with or without cilostazol ($10{\mu}M$). Pretreatment with cilostazol markedly reduced TNF-${\alpha}$-induced viability loss in the HUVECs, which was reversed by zinc protoporphyrine IX (ZnPP), an inhibitor of HO-1. Moreover, cilostazol increased HO-1 protein and mRNA expression. Cilostazol-induced HO-1 induction was markedly attenuated not only by ZnPP but also by copper-protoporphyrin IX (CuPP). In an assay measuring peroxisome proliferator-activated receptor-${\gamma}$ (PPAR-${\gamma}$) transcription activity, cilostazol directly increased PPAR-${\gamma}$ transcriptional activity which was completely abolished by HO-1 inhibitor. Furthermore, increased PPAR-${\gamma}$ activity by cilostazol and rosiglitazone was completely abolished in cells transfected with HO-1 siRNA. Taken together, these results indicate that cilostazol up-regulates HO-1 and protects cells against TNF-${\alpha}$-induced endothelial cytotoxicity via a PPAR-${\gamma}$-dependent pathway.

• Korean Journal of Pharmacognosy
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• v.44 no.4
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• pp.397-401
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• 2013

The Galkun-Whanglyeon-Whanggum-Tang, an officially standardized mixture of traditional herbal medicines used in Korea and China, consists of Pueraria lobata, Scullellaria baicalensis, Coptis chinensis and Glycyrrhiza uralensis at a ratio of 6:9:3:2.4. In this study, we evaluated the effect of lowering lipid accumulation in blood by treatment of Galkun-Whanglyeon-Whanggum-Tang in Apo E(-/-) atherosclerotic animal model. ApoE/mice fed with 1.25% cholesterol, 7.5% cocoa butter and 0.5% sodium cholate diet were orally given vehicle or Galkun-Whanglyeon-Whanggum-Tang(10, 100 and 300 mg/kg/day) for 12 weeks. Serum levels of triglyceride(TG), total cholestrerol(TC), low-density lipoprotein(LDL) and high-density lipoprotein(HDL) were analyzed, and PPAR-${\alpha}$ and PPAR-${\gamma}$ were examined by Western blotting analysis. Galkun-Whanglyeon- Whanggum-Tang decreased serum levels of TG, TC and LDL, but not HDL in ApoE/mice. In parallel, Galkun-Whanglyeon-Whanggum-Tang treatment showed the increased activity of PPAR-${\alpha}$ and PPAR-${\gamma}$ in hepatocytes. In summary, Galkun-Whanglyeon-Whanggum-Tang can reduce lipid accumulation in blood, and this effect might be accompanied by the upregulation of PPAR-${\alpha}$ and PPAR-${\gamma}$ in Apo E(-/-) atherosclerotic mouse model.

• International Journal of Oral Biology
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• v.43 no.1
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• pp.29-35
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• 2018

It is noted that chalcone derivatives have characteristic diverse pharmacological properties, and that precise evidence has been growing that they could regulate a tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) induced insulin resistance. The purpose of the present investigation is to elucidate the effects of the identified chalcone derivatives on adipogenesis, and to find the underlying mechanism of action in that case. Consequently, we first investigated whether the chalcone derivatives could affect the identified $PPAR{\gamma}$-induced transcriptional activity on the proliferator-activated receptor response elements (PPRE) at target promoters, and find that trans-chalcone most significantly increased the $PPAR{\gamma}$-induced transcriptional activity. Additionally, we confirmed that there were up-regulatory effects of trans-chalcone during the adipogenesis and lipid accumulation, and on the mRNA of adipogenic factors in 3T3-L1 cells. Next, we examined the effect of trans-chalcone on the inhibition induced by $TNF-{\alpha}$ on adipogenesis. To that end, we noted that the treatment with trans-chalcone attenuated the effect of $TNF-{\alpha}$ mediated secretion of various adipokines that are involved in insulin sensitivity. For this reason, we noted that this study clearly demonstrates that trans-chalcone enhanced adipogenesis, in part, by its potent effect on $PPAR{\gamma}$ activation and by its reverse effect on $TNF-{\alpha}$.

• Korean Journal of Acupuncture
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• v.32 no.3
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• pp.116-123
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• 2015

Objectives : The present study was designed to investigate effects and molecular mechanisms of Atractylodes macrocephala Koidzumi extracts(AMK) on the improvement of adipocyte dysfunction induced by TNF-${\alpha}$ in 3T3-L1 adipocytes. We examined whether AMK could directly influence the inflammation and insulin resistance in 3T3-L1 adipocytes. Methods : Potential roles of AMK in the lipolysis, production of inflammatory adipokines and ROS, expression and phosphorylation of ERK, JNK, and $I{\kappa}B{\alpha}$ protein, and expression of $PPAR{\gamma}$ and C/EBP${\alpha}$ were investigated in this study. Results : Our data demonstrated that TNF-${\alpha}$ significantly increased lipolysis, levels of MCP-1, IL-6, and ROS and phosphorylation of ERK, JNK, and $I{\kappa}B{\alpha}$ protein, while TNF-${\alpha}$ reduced the expression of $PPAR{\gamma}$ and C/EBP${\alpha}$ in adipocytes, suggesting that TNF-${\alpha}$ induced a condition with the occurrence of inflammation and insulin resistance. Those alterations induced by TNF-${\alpha}$ were prevented by the treatment of AMK. AMK down-regulated the phosphorylation of ERK, JNK, and $I{\kappa}B{\alpha}$ protein and up-regulated the expression of $PPAR{\gamma}$ and C/EBP${\alpha}$ on TNF-${\alpha}$-induced inflammation and insulin resistance. Conclusions : Thus, our results indicate that AMK can be used to prevent from the TNF-${\alpha}$-induced adipocyte dysfunction through MAPK, $NF{\kappa}B$ and $PPAR{\gamma}$ pathways.

• Journal of Life Science
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• v.22 no.10
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• pp.1316-1323
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• 2012

The present study was conducted to investigate whether myoblasts can be transdifferentiated into adipocytes by ectopic expression of adipogenic transcription factors, including peroxisome proliferator-activated receptor-${\gamma}$ ($PPAR{\gamma}$), CCAAT/enhancer-binding protein-${\alpha}$ (C/$EBP{\alpha}$), sterol regulatory element binding protein-1c (SREBP1c), and Krueppel-like factor 5 (KLF5), in primary bovine satellite cells. Transcription factors were transiently transfected into primary bovine myoblasts, and the cells were cultured with adipogenic differentiation medium for 2 days and then cultured on growth medium for an additional 8 days. Ectopic expression of $PPAR{\gamma}$ or C/$EBP{\alpha}$ alone was insufficient to induce adipogenesis in myoblasts. However, overexpression of both $PPAR{\gamma}$ and C/$EBP{\alpha}$ in myoblasts was able to induce adipogenic transdifferentiation as indicated by the appearance of mature adipocytes, the induction of adipogenic gene expressions, and the suppression of myogenic gene expressions. In addition, KLF5 and $PPAR{\gamma}$ co-transfected bovine myoblasts were converted to adipocytes but not in cells transfected with only KLF5 expression vector. Overexpression of SREBP1c alone was sufficient to induce transdifferentiation from myoblasts into adipocytes. These results demonstrate that primary bovine satellite cells can be transdifferentiated into adipocytes either by single ectopic expression or combined expression of adipogenic transcription factors in a culture system.

• BMB Reports
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• v.42 no.2
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• pp.91-95
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• 2009

Peroxisome proliferator-activated receptor $\alpha$ and estrogen are believed to be involved in metabolic changes leading to obesity. To test this relationship, we divided female wildtype and PPAR$\alpha$-deficient mice fed on a high fat diet into the following groups: mock-operated, ovariectomized (OVX), and $E_2$-treated. The visceral white adipose tissue and plasma cholesterol levels were increased significantly in wild type OVX and decreased in the $E_2$-treated group, but interestingly not in PPAR$\alpha$-deficient mice. The mRNA levels of lipoprotein lipase in adipose tissue were also increased in only wild type OVX and decreased significantly in $E_2$-treated mice. These novel results suggest the possibility of signaling crosstalk between PPAR$\alpha$ and $E_2$, causing obesity in vivo.

• Journal of Veterinary Clinics
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• v.31 no.6
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• pp.469-476
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• 2014

The aims of this study were to explore the effects of conjugated linoleic acid (CLA) on reactive oxygen species (ROS) production in lipopolysaccharide (LPS)-naïve and LPS-stimulated RAW 264.7 macrophages and to examine whether these effects affect the regulation of tumor necrosis factor-alpha (TNF-${\alpha}$) production, and nuclear factor-kappa B (NF-${\kappa}B$) and peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) activation. Trans-10, cis-12(t10c12)-CLA increased the production of ROS, as well as TNF-${\alpha}$ in LPS-naïve RAW 264.7 cells. The CLA-induced TNF-${\alpha}$ production was suppressed by treatment of diphenyleneiodonium chloride (DPI), a NADPH oxidase inhibitor. In addition, CLA enhanced the activities of NF-${\kappa}B$ and $PPAR{\gamma}$ in LPS-naïve RAW 264.7 cells, and this effect was abolished with DPI treatment. LPS treatment increased ROS production, whereas CLA reduced LPS-induced ROS production. LPS increased both TNF-${\alpha}$ production and NF-${\kappa}B$ activity, whereas t10c12-CLA reduced TNF-${\alpha}$ production and NF-${\kappa}B$ activity in LPS-stimulated RAW 264.7 cells. DPI treatment suppressed LPS-induced ROS production and NF-${\kappa}B$ activity. Moreover, DPI enhanced the inhibitory effects of t10c12-CLA on TNF-${\alpha}$ production and NF-${\kappa}B$ activation in LPS-stimulated RAW 264.7 cells. However, neither t10c12-CLA nor DPI affected $PPAR{\gamma}$ activity in LPS-stimulated RAW 264.7 cells. Taken together, these data indicate that t10c12-CLA induces TNF-${\alpha}$ production by increasing ROS production in LPS-naïve RAW 264.7 cells, which is mediated by the enhancement of NF-${\kappa}B$ activity via $PPAR{\gamma}$ activation. By contrast, t10c12-CLA suppresses TNF-${\alpha}$ production by inhibiting ROS production and NF-${\kappa}B$ activation via a $PPAR{\gamma}$-independent pathway in LPS-stimulated RAW 264.7 cells. These results suggest that t10c12-CLA can modulate TNF-${\alpha}$ production and NF-${\kappa}B$ activation through formation of ROS in RAW 264.7 macrophages.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.963-971
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• 2014

This study investigated the effects of exercise intensity on PGC-$1{\alpha}$, PPAR-${\gamma}$, and insulin resistance in skeletal muscle of high fat diet-fed Sprague-Dawley rats. Forty rats were randomly divided into five groups: sedentary control group (SED), high fat diet group (HF), high fat diet+low-intensity exercise group (HFLE, 22 m/min, 60 min, 6 days/week), high fat diet+moderate-intensity exercise group (HFME, 26 m/min, 51 min), and high fat diet+high-intensity exercise group (HFHE, 30 m/min, 46 min). After 4 weeks of high fat diet and endurance exercise training, the lipid profiles, insulin, and glucose concentrations were determined in plasma. PGC-$1{\alpha}$, PPAR-${\gamma}$, and GLUT-4 contents were measured in plantaris muscle. The rate of glucose transport in soleus muscle was determined under submaximal insulin concentration ($1,000{\mu}IU/mL$ insulin, 20 min) during muscle incubation. Plasma glucose during oral glucose tolerance test in HF was significantly greater than that in SED, and plasma glucose levels in the three exercise (EX) groups were significantly lower that those in SED and HF at 30 and 60 min, respectively (P<0.05). Plasma insulin levels in the EX groups were significantly reduced by 60 min compared to that in HF (P<0.05). The protein expression level of PGC-$1{\alpha}$ as well as muscle glucose uptake were significantly higher in SED and HF than those in the three EX groups (P<0.05), and HFHE showed significantly higher levels than HFLE and HFME. Expression levels of GLUT-4 and PPAR-${\gamma}$ were significantly higher in the HFLE, HFME, and HFHE groups compared to the SED and HF (P<0.05). Therefore, the results of this study indicate that 4 weeks of high fat diet significantly developed whole body insulin resistance but did not affect PGC-$1{\alpha}$, PPAR-${\gamma}$, or the glucose transport rate in skeletal muscle, and exercise training was able to attenuate deteriorated whole body insulin resistance due to high fat diet. In addition, high intensity training significantly affected PGC-$1{\alpha}$ expression and the glucose transport rate of skeletal muscle in comparison with low and middle training intensities.

• Restorative Dentistry and Endodontics
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• v.31 no.3
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• pp.203-214
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• 2006

Dental pulp is a loose, mesenchymal tissue almost entirely enclosed in the dentin. It consists of cells, ground substance, and neural and vascular supplies. Damage to the dental pulp by mechanical, chemical, thermal, and microbial irritants can provoke various types of inflammatory response. Pulpal inflammation leads to the tissue degradation, which is mediated in part by Matrix metalloproteinase leads to accelerate extracellular matrix degradation with pathological pathway We have now investigated the induction of MMPs and inflammatory cytokines by Lipopolysaccharide (LPS) control of inflammatory mediators by peroxisome proliferator-activated receptors (PPARs). Human dental pulp cells exposed to various concentrations of LPS ($1-10{\mu}g/ml$) revealed elevated levels of MMP-2 and MMP-9 at 24 hrs of culture. LPS also stimulated the production of ICAM-1, VCAM-1, $IL-1{\beta},\;and\;TNF-{\alpha}$. Adenovirus $PPAR{\gamma}\;(Ad/PPAR{\gamma})\;and\;PPAR{\gamma}$ agonist rosiglitazone reduced the synthesis of MMPs, adhesion molecules and pro-inflammatory cytokines. The inhibitory effect of $Ad/PPAR{\gamma}$ was higher than that of $PPAR{\gamma}$ agonist. These result offer new insights in regard to the anti-inflammatory potential of $PPAR{\gamma}$ in human dental pulp cell.