• Asian-Australasian Journal of Animal Sciences
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• v.32 no.11
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• pp.1789-1800
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• 2019

Objective: Although alveolar macrophages play a key role in the respiratory immunity of livestock, studies on the mechanism of differentiation and survival of alveolar macrophages are lacking. Therefore, we undertook to investigate changes in the lipid metabolism and survival rate, using 3D4/31 macrophages and Dudleya brittonii which has been used as a traditional asthma treatment. Methods: 3D4/31 macrophages were used as the in vitro porcine alveolar macrophages model. The cells were activated by exposure to phorbol 12-myristate 13-acetate (PMA). Dudleya brittonii extraction was performed with distilled water. For evaluating the cell survival rate, we performed the water-soluble tetrazolium salt cell viability assay and growth curve analysis. To confirm cell death, cell cycle and intracellular reactive oxygen species (ROS) levels were measured using flow cytometric analysis by applying fluorescence dye dichlorofluorescein diacetate and propidium iodide. Furthermore, we also evaluated cellular lipid accumulation with oil red O staining, and fatty acid synthesis related genes expression levels using quantitative polymerase chain reaction (qPCR) with SYBR green dye. Glycolysis, fatty acid oxidation, and tricarboxylic acid (TCA) cycle related gene expression levels were measured using qPCR after exposure to Dudleya brittonii extract (DB) for 12 h. Results: The ROS production and cell death were induced by PMA treatment, and exposure to DB reduced the PMA induced downregulation of cell survival. The PMA and DB treatments upregulated the lipid accumulation, with corresponding increase in the acetyl-CoA carboxylase alpha, fatty acid synthase mRNA expressions. DB-PMA co-treatment reduced the glycolysis genes expression, but increased the expressions of fatty acid oxidation and TCA cycle genes. Conclusion: This study provides new insights and directions for further research relating to the immunity of porcine respiratory system, by employing a model based on alveolar macrophages and natural materials.

• Journal of Animal Science and Technology
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• v.64 no.6
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• pp.1199-1214
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• 2022

Apolipoprotein H (APOH) primarily engages in fat metabolism and inflammatory disease response. This study aimed to investigate the effects of APOH on fat synthesis in duck myoblasts (CS2s) by APOH overexpression and knockdown. CS2s overexpressing APOH showed enhanced triglyceride (TG) and cholesterol (CHOL) contents and elevated the mRNA and protein expression of AKT serine/threonine kinase 1 (AKT1), ELOVL fatty acid elongase 6 (ELOVL6), and acetyl-CoA carboxylase 1 (ACC1) while reducing the expression of protein kinase AMP-activated catalytic subunit alpha 1 (AMPK), peroxisome proliferator activated receptor gamma (PPARG), acyl-CoA synthetase long chain family member 1 (ACSL1), and lipoprotein lipase (LPL). The results showed that knockdown of APOH in CS2s reduced the content of TG and CHOL, reduced the expression of ACC1, ELOVL6, and AKT1, and increased the gene and protein expression of PPARG, LPL, ACSL1, and AMPK. Our results showed that APOH affected lipid deposition in myoblasts by inhibiting fatty acid beta-oxidation and promoting fatty acid biosynthesis by regulating the expression of the AKT/AMPK pathway. This study provides the necessary basic information for the role of APOH in fat accumulation in duck myoblasts for the first time and enables researchers to study the genes related to fat deposition in meat ducks in a new direction.

• The Journal of Internal Korean Medicine
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• v.37 no.3
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• pp.442-452
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• 2016

Objectives: This study was performed to investigate the anti-lipogenic effect and the mechanism of Jungmanbunso-hwan extract (JMBSH) on a cellular model of non-alcoholic fatty liver disease (NAFLD) caused by palmitate in HepG2 cells.Methods: The JMBSH was prepared, andHepG2 cells were treated with various concentrations of JMBSH in order to perform an MTT assay. The HepG2 cells were cultivated in palmitate-containing media with or without extract of JMBSH. The intracellular lipid content in the HepG2 cells was examined. The effects of JMBSH on sterol regulatory element-binding transcription factor-1c (SREBP-1c), acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), stearoyl-CoA desaturase-1 (SCD-1), and AMP-activated protein kinase (AMPK) activation in HepG2 cells were measured.Results: JMBSH did not reduce HepG2 cell viability under 1,000 μg/mL. JMBSH considerably decreased intracellular lipid accumulation caused by palmitate in HepG2 cells. JMBSH repressed expression of SREBP-1c, which mediates the induction of lipogenic genes (ACC, FAS, and SCD-1). JMBSH also activated AMPK, which plays animportant role in the regulation of hepatic lipid metabolism.Conclusions: This study suggested that JMBSH relieves hepatic steatosis by repressing SREBP-1c, which mediates the induction of lipogenic genes. The anti-lipogenic effect of JMBSH may also be related to the activation of AMPK. Therefore, JMBSH could potentially be applied to NAFLD treatment after further clinical studies.

• Journal of Veterinary Science
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• v.23 no.1
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• pp.4.1-4.15
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• 2022

Background: Flavonoids are natural polyphenols found widely in citrus fruit and peel that possess anti-adipogenic effects. On the other hand, the detailed mechanisms for the antiadipogenic effects of flavonoids are unclear. Objectives: The present study observed the anti-adipogenic effects of five major citrus flavonoids, including hesperidin (HES), narirutin (NAR), nobiletin (NOB), sinensetin (SIN), and tangeretin (TAN), on AMP-activated protein kinase (AMPK) activation in palmitate (PA)-treated HepG2 cells. Methods: The intracellular lipid accumulation and triglyceride (TG) contents were quantified by Oil-red O staining and TG assay, respectively. The glucose uptake was assessed using 2-[N-(7-Nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-d-glucose (2-NBDG) assay. The levels of AMPK, acetyl-CoA carboxylase (ACC), and glycogen synthase kinase 3 beta (GSK3β) phosphorylation, and levels of sterol regulatory element-binding protein 2 (SREBP-2) and 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) expression were analyzed by Western blot analysis. The potential interaction between the flavonoids and the γ-subunit of AMPK was investigated by molecular docking analysis. Results: The flavonoid treatment reduced both intracellular lipid accumulation and TG content in PA-treated HepG2 cells significantly. In addition, the flavonoids showed increased 2-NBDG uptake in an insulin-independent manner in PA-treated HepG2 cells. The flavonoids increased the AMPK, ACC, and GSK3β phosphorylation levels and decreased the SREBP-2 and HMGCR expression levels in PA-treated HepG2 cells. Molecular docking analysis showed that the flavonoids bind to the CBS domains in the regulatory γ-subunit of AMPK with high binding affinities and could serve as potential AMPK activators. Conclusion: The overall results suggest that the anti-adipogenic effect of flavonoids on PA-treated HepG2 cells results from the activation of AMPK by flavonoids.

• The Journal of Korean Medicine
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• v.27 no.3 s.67
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• pp.14-25
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• 2006

Objectives: Samjunghwan has been known to be effective for the treatment of obesity. To show the effectiveness of Samjunghwan in a more scientific way, Samjunghwan extract was prepared and evaluated in high-fat diet rats by measuring the changes of body weight and lipid metabolism as described below. Methods: 245 g of crushed Samjunghwan was extracted with methyl alcohol. The extract was evaporated under reduced pressure to give 21.8 g. For 30 days, the control group rats were given a high fat diet, while the test group rats were given a high fat diet plus Samjunghwan extract. The normal group rats were given a normal diet. 50 mg of Samjunghwan extract per 1 kg of body weight was added to the diet for the test group rats. Results: The control group rats on a high fat diet gained weight by about 27-28% as compared to the normal group, whereas the test group rats on a high fat diet plus Samjunghwan extract lost weight about 6-8% as compared to the control group. A significant increase of liver weight caused by a high fat diet was also inhibited by the same Samjunghwan extract administration. Similar inhibitory effects on the food intake and on the epididymal adipose tissue weight were observed in the high fat diet rats by the administration of Samjunghwan extract. Serum and liver total lipid levels in the control group on a high fat diet increased significantly as compared to the normal group, whereas their serum and liver levels increased less on a high fat diet plus Samjunghwan extract administered test group than the control group. Impressively, serum leptin levels in the test group decreased almost to the level of the normal group, which was well in accordance with the decreased fat contents in the test group rats. Furthermore, the activities of hepatic acetyl-CoA carboxylase and fatty acid synthetase were increased in the control group, while their activities in the test group on a high fat diet plus Samjunghwan extract decreased nearly to the levels of normal group rats on a normal diet. Conclusions: These results showed that the obesity caused by a high fat diet was effectively inhibited the administration of Samjunghwan extract. Our results also showed that the abnormal lipid metabolism caused by a high fat diet was effectively cured by the administration of Samjunghwan extract.

• Journal of Microbiology and Biotechnology
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• v.22 no.8
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• pp.1127-1132
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• 2012

Nargenicin $A_1$ is a 28-membered polyketide macrolide, with antibacterial activity against methicillin-resistant Staphylococcus aureus, produced by Nocardia sp. CS682. In this study, the production of nargenicin $A_1$ was improved by enhancing the supply of different biosynthetic precursors. In Nocardia sp. CS682 (KCTC11297BP), this improvement was ~4.62-fold with the supplementation of 30 mM methyl oleate, 4.25-fold with supplementation of 15mM sodium propionate, and 2.81-fold with supplementation of 15 mM sodium acetate. In Nocardia sp. metK18 and Nocardia sp. CS682 expressing S-adenosylmethionine synthetase (MetK), the production of nargenicin $A_1$ was improved by ~5.57-fold by supplementation with 30 mM methyl oleate, 5.01-fold by supplementation with 15 mM sodium propionate, and 3.64-fold by supplementation with 15 mM sodium acetate. Furthermore, supplementing the culture broth of Nocardia sp. ACC18 and Nocardia sp. CS682 expressing the acetyl-CoA carboxylase complex (AccA2 and AccBE) with 30 mM methyl oleate, 15 mM sodium propionate, or 15 mM sodium acetate resulted in ~6.99-, 6.46-, and 5.58-fold increases, respectively, in nargenicin $A_1$ production. Our overall results showed that among the supplements, methyl oleate was the most effective precursor supporting the highest titers of nargenicin $A_1$ in Nocardia sp. CS682, Nocardia sp. metK18, and Nocardia sp. ACC18.

• Journal of Ginseng Research
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• v.17 no.2
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• pp.101-108
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• 1993

This study was made to understand a hypoglycemic action of the fat soluble fraction of Panax ginseng C.A. Meyer in streptozotocin induced diabetic rats by determining the activities of several enzymes related to carbohydrate and lipid metabolism as well as several blood component levels such as glucose and ketone bodies, and non-esterified fatty acids. Albino rats (Sprague Dawley, 170-200g, 3) were injected once with 70mg streptozotocinhg body weight intraperitoneally and fed with ordinary diet for 7 days, and then the fat soluble fraction (5 mg~20 mg/day/rat) was injected intraperitoneally once a day for three days to rats having high blood glucose level over 340 mg/100ml. After a final injection of the fat soluble fraction, rats u.ere starved for 16 hours followed by the analysis of blood serum and liver enzymes. It was found that increased levels of glucose, ketone bodies and free fatty acids in streptozotocin induced rats were decreased appreciably by administration of the fat soluble fraction. However, the amount of administered fat soluble fraction did not show any significantly different hypoglycemic action. Decreased activities of glucokinase, phosphofructokinase, pyruvate kinase, 6-phosphogluconate dehydrogenase and acetyl CoA carboxylase of the liver of streptozotocin induced diabetic rats were greatly modified suggesting that a hypoglycemic action of the fat soluble fraction was also appreciable as ginseng saponin fraction. We also compared a hypoglycemic action of the fat soluble fraction prepared from American ginseng and Chinese ginseng with that of Korean pain ginseng. 핀o significant difference of the hypoglycemic activity was observed between the above ginseng fat soluble fractions, suggesting that a study of the fat soluble fraction might be one of the most interesting subjects relating to diabetic hyperglycemia in the near future.

• Toxicological Research
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• v.29 no.1
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• pp.7-14
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• 2013

Betaine supplementation has been shown to alleviate altered glucose and lipid metabolism in mice fed a high-fat diet or a high-sucrose diet. We investigated the beneficial effects of betaine in diabetic db/db mice. Alleviation of endoplasmic reticulum (ER) and oxidative stress was also examined in the livers and brains of db/db mice fed a betaine-supplemented diet. Male C57BL/KsJ-db/db mice were fed with or without 1% betaine for 5 wk (referred to as the db/db-betaine group and the db/db group, respectively). Lean non-diabetic db/+ mice were used as the control group. Betaine supplementation significantly alleviated hyperinsulinemia in db/db mice. Betaine reduced hepatic expression of peroxisome proliferator-activated receptor gamma coactivator 1 alpha, a major transcription factor involved in gluconeogenesis. Lower serum triglyceride concentrations were also observed in the db/db-betaine group compared to the db/db group. Betaine supplementation induced hepatic peroxisome proliferator-activated receptor alpha and carnitine palmitoyltransferase 1a mRNA levels, and reduced acetyl-CoA carboxylase activity. Mice fed a betaine-supplemented diet had increased total glutathione concentrations and catalase activity, and reduced lipid peroxidation levels in the liver. Furthermore, betaine also reduced ER stress in liver and brain. c-Jun N-terminal kinase activity and tau hyperphosphorylation levels were lower in db/db mice fed a betaine-supplemented diet, compared to db/db mice. Our findings suggest that betaine improves hyperlipidemia and tau hyperphosphorylation in db/db mice with insulin resistance by alleviating ER and oxidative stress.

• Nutrition Research and Practice
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• v.12 no.4
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• pp.298-306
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• 2018

BACKGROUND/OBJECTIVES: Obesity is a global health problem of significant importance which increases mortality. In place of anti-obesity drugs, natural products are being developed as alternative therapeutic materials. In this study, we investigated the effect of Brassica juncea L. leaf extract (BLE) on fat deposition and lipid profiles in high-fat, high-cholesterol diet (HFC)-induced obese rats. MATERIALS/METHODS: Male Sprague-Dawley rats were divided into four groups (n = 8 per group) according to diet: normal diet group (ND), high-fat/high-cholesterol diet group (HFC), HFC with 3% BLE diet group (HFC-A1), and HFC with 5% BLE diet group (HFC-A2). Each group was fed for 6 weeks. Rat body and adipose tissue weights, serum biochemical parameters, and tissue lipid contents were determined. The expression levels of mRNA and proteins involved in lipid and cholesterol metabolism were determined by reverse transcription polymerase chain reaction and western blot analysis, respectively. RESULTS: The HFC-A2 group showed significantly lower body weight gain and food efficiency ratio than the HFC group. BLE supplementation caused mesenteric, epididymal, and total adipose tissue weights to decrease. The serum levels of triglyceride, total cholesterol, and low-density lipoprotein cholesterol were significantly reduced, and high-density lipoprotein cholesterol was significantly increased in rats fed BLE. These results were related to lower glucose-6-phosphate dehydrogenase, acetyl-coA carboxylase, and fatty acid synthase mRNA expression, and to higher expression of the cholesterol $7{\alpha}$-hydroxylase and low density lipoprotein-receptor, as well as increased protein levels of peroxisome proliferator-activated receptor ${\alpha}$. Histological analysis of the liver revealed decreased lipid droplets in HFC rats treated with BLE. CONCLUSIONS: Supplementation of HFC with 3% or 5% BLE inhibited body fat accumulation, improved lipid profiles, and modulated lipogenesis- and cholesterol metabolism-related gene and protein expression.

• BMB Reports
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• v.57 no.2
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• pp.92-97
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• 2024

Elevated blood glucose is associated with an increased risk of atherosclerosis. Data from the current study showed that glucosamine (GlcN), a normal glucose metabolite of the hexosamine biosynthetic pathway (HBP), promoted lipid accumulation in RAW264.7 macrophage cells. Oleic acid- and lipopolysaccharide (LPS)-induced lipid accumulation was further enhanced by GlcN in RAW264.7 cells, although there was no a significant change in the rate of fatty acid uptake. GlcN increased acetyl CoA carboxylase (ACC), fatty acid synthase (FAS), scavenger receptor class A, liver X receptor, and sterol regulatory element-binding protein-1c (SREBP-1c) mRNA expression, and; conversely, suppressed ATP-binding cassette transporter A1 (ABCA-1) and ABCG-1 expression. Additionally, GlcN promoted O-GlcNAcylation of nuclear SREBP-1 but did not affect its DNA binding activity. GlcN stimulated phosphorylation of mammalian target of rapamycin (mTOR) and S6 kinase. Rapamycin, a mTOR-specific inhibitor, suppressed GlcN-induced lipid accumulation in RAW264.7 cells. The GlcN-mediated increase in ACC and FAS mRNA was suppressed, while the decrease in ABCA-1 and ABCG-1 by GlcN was not significantly altered by rapamycin. Together, our results highlight the importance of the mTOR signaling pathway in GlcN-induced macrophage lipid accumulation and further support a potential link between mTOR and HBP signaling in lipogenesis.