• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.1
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• pp.39-46
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• 2009

This study investigated the beneficial effects of crude saponins from soybean cake on body weight and glucose tolerance in high-fat (37% calories from fat) diet fed C57BL/6 mice. The mice were supplemented with three doses of saponins (0.5%, 1.0%, and 1.5%, wt/wt) and 1.0% Garcinia cambogia (wt/wt), positive control for 9 weeks. The body weight, visceral fat weight and epididymal adipocyte area were significantly reduced in the saponin supplemented groups in a dose dependent manner compared to the high-fat group. Saponins did not significantly affect food intake; however, cambogia significantly lowered food intake compared to the high-fat fed control group. The crude saponins from soybean cake supplement significantly lowered plasma leptin, triglyceride and total cholesterol levels, whereas they significantly elevated the fecal excretion of triglyceide in a dose dependent manner compared to the high-fat group. Cambogia did not affect the fecal excretion of lipid in the diet-induced obese mice. Supplementation of 1.5% saponin reduced the hepatic triglyceride content compared to the high-fat group. High-fat induced glucose intolerance with the elevation of blood glucose levels compared to the normal group; however, the saponins supplement significantly improved postprandial glucose levels. After 9 weeks of being fed a high-fat diet, the mice presented with significantly increased activities of hepatic fatty acid synthase and fatty acid ${\beta}$-oxidation; however, saponins and cambogia normalized these activities. These results indicate that saponins from soybean cake exhibit a potential anti-obesity effect and may prevent glucose intolerance by reducing body weight and plasma lipids, increasing fecal lipid excretion and regulating hepatic lipid metabolism in high-fat fed mice.

• Journal of Nutrition and Health
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• v.55 no.4
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• pp.462-475
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• 2022

Purpose: Allomyrina dichotoma larvae are one of the approved edible insects with nutritional value and various functional and medicinal properties. Previously we have demonstrated that the Allomyrina dichotoma larval extract (ADLE) ameliorates hepatic insulin resistance in high-fat diet (HFD)-induced diabetic mice through the activation of adenosine monophosphate-activated protein kinase (AMPK). This study investigated the effects of ADLE on insulin resistance in the skeletal muscle and explored mechanisms for enhancing the glucose uptake in palmitate (PAL)-treated C2C12 myotubes. Methods: To induce insulin resistance, the differentiated C2C12 myotubes were treated with PAL (0.5 mM) for 24 hours, and then treated with a 0.5 mg/ml concentration of ADLE, and the resultant effects were measured. The expression levels of glucose transporter-4 (GLUT4), AMPK, and the mitochondrial metabolism-related proteins were analyzed by western blotting. The mRNA expression levels of lipogenesis- related genes were determined by quantitative reverse-transcriptase PCR. Results: The exposure of C2C12 myotubes to 0.5 mg/ml of ADLE increased cell viability significantly compared to PAL-treated cells. ADLE upregulated the protein expression of GLUT4 and enhanced glucose uptake in the PAL-treated cells. ADLE increased the phosphorylated AMPK in both the PAL-treated C2C12 myotubes and HFD-treated skeletal muscle. The reduced expression levels of peroxisome-proliferator-activated receptor gamma co-activator-1 alpha (PGC1α) and uncoupling protein 3 (UCP3) due to the PAL and HFD treatment were reversed by the ADLE treatment. The citrate synthase activity was also significantly increased with the PAL and ADLE co-treatment. Moreover, the mRNA and protein expressions of fatty acid synthesis-related factors were reduced in the PAL and HFD-treated muscle cells, and this effect was significantly attenuated by the ADLE treatment. Conclusion: ADLE activates AMPK, which in turn induces mitochondrial metabolism and reduces fatty acid synthesis in C2C12 myotubes. Therefore, ADLE could be useful for preventing or treating insulin resistance of skeletal muscles in diabetes.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.1
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• pp.10-18
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• 2014

The objective of this study was to investigate the correlation between cattle breeds and deposit of adipose tissues in different positions and the gene expressions of peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$), fatty acid synthase (FASN), and Acyl-CoA dehydrogenase (ACADM), which are associated with lipid metabolism and are valuable for understanding the physiology in fat depot and meat quality. Yanbian yellow cattle and Yan yellow cattle reared under the same conditions display different fat proportions in the carcass. To understand this difference, the expression of $PPAR{\gamma}$, FASN, and ACADM in different adipose tissues and longissimus dorsi muscle (LD) in these two breeds were analyzed using the Real-time quantitative polymerase chain reaction method (qRT-PCR). The result showed that $PPAR{\gamma}$ gene expression was significantly higher in adipose tissue than in LD in both breeds. $PPAR{\gamma}$ expression was also higher in abdominal fat, in perirenal fat than in the subcutaneous fat (p<0.05) in Yanbian yellow cattle, and was significantly higher in subcutaneous fat in Yan yellow cattle than that in Yanbian yellow cattle. On the other hand, FASN mRNA expression levels in subcutaneous fat and abdominal fat in Yan yellow cattle were significantly higher than that in Yanbian yellow cattle. Interestingly, ACADM gene shows greater fold changes in LD than in adipose tissues in Yan yellow cattle. Furthermore, the expressions of these three genes in lung, colon, kidney, liver and heart of Yanbian yellow cattle and Yan yellow cattle were also investigated. The results showed that the highest expression levels of $PPAR{\gamma}$ and FASN genes were detected in the lung in both breeds. The expression of ACADM gene in kidney and liver were higher than that in other organs in Yanbian yellow cattle, the comparison was not statistically significant in Yan yellow cattle.

• Journal of Applied Biological Chemistry
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• v.60 no.1
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• pp.23-28
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• 2017

Amomum tsao-ko used as a traditional oriental herbal medicine, is indigenous to several Asia countries. In this study, we investigated anti-obesity activity of the ethanol extract of Amomum Taso-ko (A. tsao-ko). The ethanol extract of A. tsao-ko inhibited adipocyte differentiation using Oil Red O assay in 3T3-L1 cells. Inhibitory effect of the ethanol extract of A. tsao-ko on adipogenesis was modulated by down-regulation adipogenic transcriptional factor such as peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$), CCAAT-enhancer-binding protein ${\alpha}$ ($C/EBP{\alpha}$) and suppressed expression of fatty acid synthase, aP2, and resistin. We demonstrated that A. tsao-ko significantly inhibited adipogenesis and reduced $PPAR{\gamma}$ and $C/EBP{\alpha}$ expression in a dose-dependent manner. These results suggest that A. tsao-ko has an anti-obesity effect by inhibition of adipogenic transcription factor and adipocyte-specific genes in 3T3-L1 cells.

• Nutrition Research and Practice
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• v.4 no.1
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• pp.3-10
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• 2010

This study was performed to investigate the effect of desalinated underground seawater (named as 'magma seawater', MSW) of Jeju Island in Korea on lipid metabolism and antioxidant activity. MSW was collected from underground of Han-Dong in Jeju Island, and freely given to high fat diet (HFD)-fed C57BL/6 mice for 10 weeks. Although there were no significant differences in the body weight changes and plasma lipid levels, hepatic triglyceride levels were significantly lower in the MSW group than in the normal tap water (TW)-drunken control group. Furthermore, the activity of fatty acid synthase (FAS) was significantly decreased and carnitine palmitoyltransferase (CPT) activity was increased in MSW group compared to TW group. Similarly, real-time PCR analysis revealed that mRNA expressions of lipogenic genes were lowered in MSW groups compared to the control group. In a morphometric observation on the liver tissue, accumulation of fats was remarkably reduced in MSW group. Meanwhile, in vitro assay, tree radical scavenging activity measured by using diphenylpicrylhydrazyl (DPPH) was increased in MSW group. The 2'-7'-dichlorofluorescein diacetate (DCF-DA) staining followed with fluorescent microscopy showed a low intensity of fluorescence in MSW-treated HepG2 cells, compared to TW-treated HepG2 cells, which indicated that the production of reactive oxygen species by tert-butyl hydroperoxide (t-BHP) in HepG2 cells was decreased by MSW treatment. The antioxidant effect of MSW on t-BHP-induced oxidative stress in HepG2 cells was supported by the increased activities of intracellular antioxidant enzymes such as catalase and glutathione reductase. From these results, we speculate that MSW has an inhibitory effect on lipogenesis in liver and might play a protective role against cell damage by t-BHP-induced oxidative stress.

• Nutritional Sciences
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• v.8 no.3
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• pp.181-188
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• 2005

We investigated the effects of diet manipulation on pro- and macro-glycogen accumulation and mobilization during exercise in different kinds of muscle fiber and tissue. Thirty-two Sprague-Dawley rats were divided into groups representing one of two dietary conditions: high fat (HF, n=16) or standard chow (CHOW, n=16). Each dietary group was fm1her divided into control (REST, n=8) and exercise (EXE, n=8). After an eight-week dietary intervention period, the animals in EXE swam for 3 hours while the animals in REST remained at rest Skeletal muscle (soleus, red gastrocnemius and white gastrocnemius) and liver samples were then dissected out and used for analyses. 1here was no statistical difference in body weight between the animals in the HF and mow groups (p>.05). Three hours of exercise significantly increased plasma free fatty acid (FFA) concentration in the animals in the CHOW group but not in the animals in the HF group. Both citrate. synthase (CS) and $\beta$-hydroxyacyl dehydrogenase ($\beta$-HAD) activities in skeletal muscles were higher in the HF group than in the mow group. CS and $\beta$-HAD activities were also the highest in red gastrocnemius and the lowest in white gastrocnemius. At both time points (i.e., rest and immediately after exercise) intramuscular triglyceride (IMTG) and liver TG concentrations were significantly higher in the HF compared to the CHOW. IMTG and liver TG changed selectively in the CHOW. Except in white gastrocnemius muscle, there was no significant difference in total glycogen content between HF and mow at rest. Although exercise significantly lowered total glycogen content in all groups and tissues (p<.05), the degree of reduction was markedly greater in the mow than in the HF. Whereas changes in proglycogen concentration showed a trend similar to those of total glycogen, alterations in macroglycogen concentrations clearly differed from those of total glycogen. Specifically, the degree of reduction of macroglycogen following three hours of exercise was substantially greater in the CHOW than in the HF. These results suggest that metabolic alterations induced by a long-term high fat diet may be caused by macro-glycogen rather than pro-glycogen.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.2
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• pp.205-212
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• 2010

The effects of chromium (Cr), dietary crude protein (CP) level, and potential interactions of these two factors were investigated in term of energy metabolism in lambs. Forty-eight 9-week-old weaned lambs (Dorper${\times}$Small-tail Han sheep, male, mean initial body weight = 22.96 kg${\pm}$2.60 kg) were used in a 2${\times}$3 factorial arrangement of supplemental Cr (0 ${\mu}g$/kg, 400 $\mu{g}$/kg or 800 ${\mu}g$/kg from chromium yeast) and protein levels (low protein: 157 g/d to 171 g/d for each animal, or high protein: 189 g/d to 209 g/d for each animal). Blood samples were collected at the beginning and end of the feeding trial. The lambs were then sacrificed and tissue samples were frozen for further analysis. Chromium at 400 ${\mu}g$/kg decreased fasting insulin level and the ratio of plasma insulin to glucagon, but these differences were not statistically significant; in contrast, chromium at 800 ${\mu}g$/kg increased the ratio significantly (p<0.05). Protein at the high level increased plasma tumor necrosis factor $\alpha$ (TNF-$\alpha$) level (p = 0.060). Liver glycogen content was increased significantly by Cr (p<0.05), which also increased liver glucose-6-phosphatase (G-6-Pase) and adipose hormone-sensitive lipase (HSL) activity. At 400 ${\mu}g$/kg, Cr increased muscle hexokinase (HK) activity. High protein significantly increased G-6-Pase activities in both the liver (p<0.05) and the kidney (p<0.05), but significantly decreased fatty acid synthase (FAS) activity in subcutaneous adipose tissue (p<0.05). For HSL activity in adipose tissue, a Cr${\times}$CP interaction (p<0.05) was observed. Overall, Cr improved energy metabolism, primarily by promoting the glycolytic rate and lipolytic processes, and these regulations were implemented mainly through the modulation by Cr of the insulin signal transduction system. High protein improved gluconeogenesis in both liver and kidney. The interaction of Cr${\times}$CP indicated that 400 $\mu{g}$/kg Cr could reduce energy consumption in situations where energy was being conserved, but could improve energy utilization when metabolic rate was increased.

• Korean Journal of Food Science and Technology
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• v.47 no.3
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• pp.364-372
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• 2015

This study investigated the effects of fermented black raspberry (BR) and red ginseng (RG) extract co-treatment on lipid metabolism and obesity in rats fed with a high fat/high cholesterol diet (HFHCD) for 12 weeks. Compared to the corresponding values in rats fed with a HFHCD, total cholesterol and low-density lipoprotein (LDL)-cholesterol and triglyceride levels decreased whereas high-density lipoprotein (HDL)-cholesterol levels increased in rats treated with fermented BR and RG extracts. These extracts significantly increased the expression of HMG-CoA reductase, LDL receptor, and sterol regulatory-element-binding protein-2 (SREBP-2) mRNA, but decreased the mRNA expression of SREBP-1. Additionally the serum levels of leptin and fatty acid synthase were decreased. Moreover, supplementation with fermented BR and RG effectively increased fecal cholesterol excretion. These results suggest that fermented BR and RG extracts might be effective at preventing hypercholesterolemia and obesity.

• Korean Journal of Food Science and Technology
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• v.47 no.4
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• pp.525-533
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• 2015

The effect of the hot water extract of defatted green tea seed cake (GTSE) on lipid metabolism and the underlying mechanisms of lipolysis in mature 3T3-L1 adipocytes were investigated. In this study, we found that the naringenin content of GTSE was 5.5 mg/g; however, catechins were not detected. The intracellular lipid droplets were stained with Oil Red O dye and quantified. Compared to the control, lipid accumulation was significantly decreased by 52%, and intracellular triglyceride (TG) level was reduced by 33% after treatment with GTSE at a concentration of $40{\mu}g/mL$. To determine the mechanism of reduction in TG content, we determined the level of fatty acid synthase (FAS), phosphorylation of adenosine monophosphate-activated protein kinase (AMPK), and acetyl-coenzyme A carboxylase (ACC) in the cell model. Incubation of the 3T3-L1 adipocytes with GTSE stimulated AMPK and ACC phosphorylation in a dose-dependent manner, and decreased the expression of FAS.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.503-509
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• 2003

For the development of the anti-obesity natural drug, the inhibitor of adipocyte differentiation was screened from Korean traditional medicinal plants. Phellodendri Cortex was selected as a candidate of adipocyte differentiation inhibitor. An inhibitory compound PC-4 was purified from the methanol (MeOH) extract of Phellodendri Cortex using silica gel and ODS RP-18 column chromatography and HPLC. PC-4 was obtained as yellow powder; UV ${\lambda}_{max}$ (MeOH): 230, 260, 340 and 430 nm. The chemical structure of PC-4 was determined as an isoquionoline alkaloid, berberine, on the basis of various NMR experiments including $^1H-\;and\;^{13}C-NMR$. The PC-4 inhibited the differentiation of preadipocyte NIH-3T3 L1 cells at a concentration of $1\;{\mu}g/mL$.