• Korean Journal of Medicinal Crop Science
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• v.28 no.6
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• pp.395-411
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• 2020

Background: This study investigated the anti-obesity effect of the flavonoid rich fraction (FRF) and its constituent, rutin obtained from the leaf of Morus alba L., on the lipid accumulation mechanism in 3T3-L1 adipocyte and C57BL/6 mouse models. Methods and Results: In Oil Red O staining, FRF (1,000 ㎍/㎖) treatments showed inhibition rate of 35.39% in lipid accumulation compared to that in the control. AdipoRedTM assay indicated that the triglyceride content in 3T3-L1 adipocytes treated with FRF (1,000 ㎍/㎖) was reduced to 23.22%, and free glycerol content was increased to 106.04% that of the control. FRF and its major constituent, rutin affected mRNA gene expression. Rutin contributed to the inhibition of Sterol regulatory element binding protein-1c (SREBP-1c) gene expression, and inhibited the transcription factors SREBP-1c, peroxisome proliferator-activated receptor gamma (PPAR-γ), CCAAT/enhancer binding protein α (C/EBPα), fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC). In addition, the effect of FRF administration on obesity development in C57BL/6 mice fed high-fat diet (HFD) was investigated. FRF suppressed weight gain, and reduced liver triglyceride and leptin secretion. FRF exerted potential anti-inflammatory effects by improving insulin resistance and adiponectin levels, and could thus be used to help counteract obesity. The mRNA expressions of PPAR-γ, FAS, ACC, and CPT-1 were determined in liver tissue. Quantitative real-time PCR analysis was also performed to evaluate the expression of IL-1β, IL-6, and TNF-α in epididymal adipose tissue. Compared to the control group, mice fed the HFD showed the up-regulation in PPAR-γ, FAS, IL-6, and TNF-α genes, and down-regulation in CPT1 gene expression. FRF treatement markedly reduced the expression of PPAR-γ, FAS, IL-6, and TNF-α compared to those in HFD control, whereas increased the expression level of CPT1. Conclusions: These results suggest that the FRF and its major active constituent, rutin, can be used as effective anti-obesity agents.

• Journal of Ginseng Research
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• v.41 no.3
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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.

• Korean Journal of Food Science and Technology
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• v.46 no.1
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• pp.100-107
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• 2014

We evaluated preventive effects of Suaeda japonica (SJ) and Spergularia marina Griseb (SMG) on the insulin resistance in Otsuka Long-Evans Tokushima Fatty (OLETF) rats. The 10-week old OLETF rats were fed diets containing 3% (w/w) SJ and SMG for 18 weeks. Fasting blood glucose levels in SJ and SMG groups, measured using the oral glucose tolerance test, were lower than that of the control rats. The SMG group showed significantly lower levels of insulin, glycated hemoglobin, triglyceride, and total cholesterol than the control group. In addition, these levels were relatively lower in the SJ group than those in the control rats. The SJ and SMG groups had relatively lower protein levels of nuclear factor-kappa B (NF-${\kappa}B$) p65 in adipose tissue and serine phosphorylated insulin receptor substrate 1 (IRS-1) in skeletal muscle than the control group. These results suggest that SJ and SMG prevent insulin resistance and SMG in particular reduces blood triglyceride and total cholesterol levels.

• Korean Journal of Plant Resources
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• v.29 no.1
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• pp.1-10
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• 2016

Obesity is a pro-inflammatory state that contributes to the development of metabolic disorders such as hyperlipidemia, insulin resistance, type 2 diabetes, non-alcoholic fatty liver, and cardiovascular disease. In this study, we evaluated the inhibition of adipogenesis in 3T3-L1 cells and in high-fat diet (HFD)-induced obese mice by Peucedanum japonicum Thunberg L. water extract (PJT). Lipid accumulation measurement indicates that PJT markedly inhibited adipogenesis in a dose-dependent manner. RT-PCR results demonstrated that the mRNA expression of adipogenic transcription factors such as peroxisome proliferator-activated receptor-γ (PPARγ) and CCAAT/enhancer binding protein-α (C/EBPα) in 3T3-L1 cells were significantly down-regulated by PJT treatment. Oral administration of PJT (100, 300, and 500 ㎎/㎏, b.w/daily for 4 weeks) was conducted in high-fat diet induced obese mice and C57BL/6 mice. The PJT-administered group of HFD-induced mice had a lower body weight gain, along with decreased serum levels of glucose, triglycerides, and total cholesterol compared with the control mice, however, the HDL-cholesterol/total cholesterol ratio was increased. Furthermore, the elevated mRNA expression levels of adipogenesis related genes in the white adipose tissue of obese mice were significantly suppressed by PJT. These results indicate that PJT exhibits anti-obesity effects in obese mice by decreasing in serum lipid levels and lipogenesis related gene.