• Journal of Life Science
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• v.29 no.10
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• pp.1144-1151
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• 2019

Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease associated with various metabolic syndromes, such as obesity, dyslipidemia, hypertension, and diabetes. Cudrania tricuspidata is a medicinal plant distributed widely in Asia and has been used in clinical practice to treat various diseases. The aim of this study is to determine the lipid-lowering effects of C. tricuspidata fruit extract (CTE) using a cell model induced by free fatty acids (FFAs). HepG2 cells were exposed to 1mM FFAs (palmitic acid:oleic acid = 2:1) for 24 hr to simulate the conditions of NAFLD in vitro. CTE attenuated the increases of lipid accumulation, intracellular triglyceride, and cholesterol content and inhibited 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) activity in the HepG2 cells in a dose-dependent manner. Also, CTE inhibited the protein expression of lipogenesis-related genes, such as sterol regulatory element-binding protein-1/-2 (SREBP-1/-2), fatty acid synthase (FAS), and stearoyl CoA desaturase-1 (SCD-1) in FFAs-induced lipid accumulation in HepG2 cells. In addition, CTE-induced adenosine monophosphate-activated protein kinase (AMPK) phosphorylation in HepG2 cells. These results suggest that CTE attenuates hepatic lipid accumulation by inhibiting lipogenesis through the modulation of the AMPK signaling pathway on FFAs-induced lipogenesis in HepG2 cells and may potentially prevent NAFLD.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.6
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• pp.802-808
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• 2013

Here we tried to uncover the potential anti-lipogenic effect and the underlying mechanism of Phaseolus angularis seed in a cellular model of nonalcoholic fatty liver disease (NAFLD) induced in HepG2 cells. Ethanol extract of Phaseolus angularis seed (JSD) was prepared. HepG2 cells were incubated in palmitate containing media to induce intracellular lipid accumulation, and co-treated with JSD for 16 hrs before examine intracellular lipid content. In control group, the cells were not co-treated with JSD. We measured the effects of JSD on liver X receptor ${\alpha}$ ($LXR{\alpha}$) and sterol regulatory element-binding transcription factor-1c (SREBP-1c) expression, transcription level of lipogenic genes, including acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), stearoyl-CoA desaturase-1 (SCD-1), and AMP-activated protein kinase (AMPK) activation in HepG2 cells. JSD markedly reduced palmitate-induced intracellular lipid accumulation in HepG2 cells. JSD suppressed $LXR{\alpha}$/SREBP-1c expression, and SREBP-1c mediated induction of ACC, FAS, and SCD-1. Furthermore, JSD activated AMPK, which plays a major role in the control of hepatic lipid metabolism. Taken together, it is suggested that JSD has a potential to alleviate hepatic steatosis, at least in part, by suppressing $LXR{\alpha}$/SREBP-1c mediated induction of lipogenic genes. In addtion, the anti-lipogenic potential may be associated with activation of AMPK. Therefore, the Phaseolus angularis seed could be applied as a potential therapeutics for NAFLD with additional clinical studies.

• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.489-497
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• 2014

We examined the effects of unripe black raspberry water extract (UBR-W) on lipid metabolism and oxidative stress in mice. C57BL/6J mice were divided into 4 groups: those administered a control diet (CTL), high-fat diet (HFD), UBR-W and simvastatin for 12 weeks. In the HFD group, LDL cholesterol were significantly higher than in the CTL group. However, the UBR-W treated group showed dose-dependent reduction of plasma LDL levels. Hepatic total lipid, TC, and malondialdehyde were significantly increased in hyperlipidemic mice. However, supplementation with either UBR-W or simvastatin effectively reduced these lipid profiles and lipid peroxidation. UBR-W increased mRNA expression of the LDL receptor, sterol regulatory element binding protein 2 (SREBP2), 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase and ATP-binding cassette transporter A1 (ABCA1) compared to that observed in the HFD group. In addition, UBR-W and simvastatin showed significantly reduced oxidized LDL uptake by the scavenger receptor CD36. These results suggest that UBR-W is useful for treatment and prevention of hyperlipidemia and lipid peroxidation.

• Korean Journal of Food Science and Technology
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• v.47 no.1
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• pp.111-118
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• 2015

In the present study, the phenolic compound level, antioxidant activity, and inhibition of lipid accumulation in Aspergillus oryzae-fermented water extracts of the Platycodon grandiflorum (PG) root and the Curcuma longa (CL) root were determined. Total polyphenol and flavonoid contents were decreased after fermentation. However, the flavonoid content of the fermented PG (FPG) was increased by 2.9-fold that of the PG before fermentation. In addition, the antioxidant activities were significantly decreased following fermentation. The potential anti-obesity activity was assessed by determining lipid accumulation and mRNA expression of sterol regulatory element-binding protein 1c (SREBP-1c) and peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) in 3T3-L1 cells. Aspergillus-fermented extracts of PG and CL roots decreased lipid accumulation, and mRNA expression of SREBP-1c and $PPAR{\gamma}$ in 3T3-L1 cells. These results indicate that Aspergillus fermentation augments the anti-obesity activity of PG and CL by regulating the expression of the genes involved in lipid accumulation and cell differentiation of 3T3-L1 cells.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.8
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• pp.1126-1131
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• 2010

The antiobesity effect of soymilks fermented with Bacillus subtilis KC-3 (KCCM 42923) from cheonggukjang was compared with other sources of B. subtilis KCCM 11316 and B. subtilis MYCO. The antiobesity effect was investigated by measuring the release of leptin, Oil red O staining, glycerol secretions and adipogenic transcription factor by reverse transcription-polymerase chain reaction (RT-PCR) in the 3T3-L1 adipocytes. Fermented soymilk with B. subtilis KC-3 (F-KC) led to decrease levels of leptin secretion and increase levels of glycerol secretion in the cells. In addition, F-KC reduced contents of Oil red O dye in the 3T3-L1 adipocytes. Also, mRNA expression levels of both SREBP-1c (sterol regulatory element-binding protein 1-c) and PPAR-$\gamma$ (peroxisome proliferator-activated receptor-$\gamma$), which are adipogenic transcription factor, in cells treated with F-KC were markedly down regulated. These results demonstrate that the Bacillus subtillis fermented soymilk (F-KC) decreased lipid content in 3T3-L1 adipocytes by inhibiting lipogenesis. All B. subtilis fermented soymilks had shown antiobesity activities, however, F-KC exhibited the strongest antiobesity effect in the 3T3-L1 adipocytes. Our study suggests that especially F-KC increased the potential of antiobesity effects.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.11
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• pp.1688-1694
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• 2014

Jeju Hallabong Tangor (Citrus kiyomi${\times}$ponkan) is a Citrus species with a variety of physiological properties such as anti-oxidant, anti-inflammation, anti-cancer, and anti-obesity. We investigated the anti-obesity effects of Hallabong Tangor peel extracts before (HLB) and after (HLB-C) bioconversion with cytolase based on modulation of adipocyte differentiation and lipid metabolism in 3T3-L1 adipocytes. Treatment with cytolase decreased flavanone rutinoside forms (narirutin and hesperidin) and increased flavanone aglycone forms (naringenin and hesperetin). During adipocyte differentiation, 3T3-L1 cells were treated with 0.5 mg/mL of Sinetrol (a positive control), HLB or HLB-C. Adipocyte differentiation was inhibited in both citrus groups, but not in control and Sinetriol groups. HLB and HLB-C tended to reduce insulin-induced mRNA levels of CCAAT/enhancer-binding protein ${\alpha}$ ($C/EBP{\alpha}$) and sterol regulatory element-binding protein 1c (SREBP1c). Compared to the control and Sinetrol groups, HLB and HLB-C markedly suppressed insulin-induced protein expression of $C/EBP{\alpha}$ and peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$). The HLB and Sinetrol groups, but not HLB-C group, significantly increased adipolytic activity with higher release of free glycerol compared to the control group in differentiated 3T3-L1 adipocytes. These results suggest that bio-conversion of Hallabong Tangor peel extracts with cytolase increases aglycone flavonoids. Irrespective of bioconversion, both Hallabong Tangor peel extracts exert anti-obesity effects that may contribute to prevention of obesity through inhibition of adipocyte differentiation or induction of adipolytic activity.

• Journal of Life Science
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• v.29 no.9
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• pp.964-971
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• 2019

Hepatic lipid accumulation and insulin resistance increases in patients with non-alcoholic fatty liver disease. Piperine is a major compound found in black pepper (Piper nigrum) and long pepper (P. longum). Piperine has been used in fine chemical for its anti-cancer, anti-obesity, anti-diabetic, anti-inflammatory and anti-oxidant properties. However, the signaling-based mechanism of piperine and its role as an inhibitor of lipogenesis and insulin resistance in human hepatocyte cells remains ill-defined. In the present study, we explored the effects of piperine on lipid accumulation and insulin resistance, and explored the potential underlying molecular mechanisms in palmitate-treated HepG2 cells. Piperine treatment resulted in a significant reduction of triglyceride content. Furthermore, piperine treatment decreased palmitate-treated intracellular lipid deposition by inhibiting the lipogenic target genes, sterol-regulatory-element-binding protein 1c (SREBP-1c) and fatty acid synthase (FAS); whereas the expression of carnitine palmitoyl transferase (CPT-1) and phosphorylation of acetyl coenzyme A carboxylase (ACC) gene involved in fatty acid oxidation was increased. Moreover, piperine also inhibited the phosphorylation of insulin receptor substrate (IRS)-1 (Ser307). Piperine treatment modulated palmitate-treated lipid accumulation and insulin resistance in HepG2 cells with concomitant reduction of lipogenic target genes, such as SREBP-1 and FAS, and induction of CPT-1-ACC and phosphorylation of IRS-1 (Tyr632)-Akt pathways. Therefore, piperine represents a promising treatment for the prevention of lipid accumulation and insulin resistance.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.5
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• pp.451-460
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• 2015

Sirtuin 1 (SIRT1) is a mammalian $NAD^+$-dependent protein deacetylase that regulates cellular metabolism and inflammatory response. The organ-specific deletion of SIRT1 induces local inflammation and insulin resistance in dietary and genetic obesity. Macrophage-mediated inflammation contributes to insulin resistance and metabolic syndrome, however, the macrophage-specific SIRT1 function in the context of obesity is largely unknown. C57/BL6 wild type (WT) or myeloid-specific SIRT1 knockout (KO) mice were fed a high-fat diet (HFD) or normal diet (ND) for 12 weeks. Metabolic parameters and markers of hepatic steatosis and inflammation in liver were compared in WT and KO mice. SIRT1 deletion enhanced HFD-induced changes on body and liver weight gain, and increased glucose and insulin resistance. In liver, SIRT1 deletion increased the acetylation, and enhanced HFD-induced nuclear translocation of nuclear factor kappa B (NF-${\kappa}B$), hepatic inflammation and macrophage infiltration. HFD-fed KO mice showed severe hepatic steatosis by activating lipogenic pathway through sterol regulatory element-binding protein 1 (SREBP-1), and hepatic fibrogenesis, as indicated by induction of connective tissue growth factor (CTGF), alpha-smooth muscle actin (${\alpha}$-SMA), and collagen secretion. Myeloid-specific deletion of SIRT1 stimulates obesity-induced inflammation and increases the risk of hepatic fibrosis. Targeted induction of macrophage SIRT1 may be a good therapy for alleviating inflammation-associated metabolic syndrome.

• Journal of Life Science
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• v.29 no.1
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• pp.60-68
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• 2019

Limonium tetragonum, an edible halophyte that grows on salt marshes in Korea, is thought to possess various health benefits (e.g., antioxidant, antitumor, and hepatoprotective). In the present study, different solvent partitioned subfractions, water ($H_2O$), buthanol (n-BuOH), 85% aqueous methanol (85% aq. MeOH), and hexane (n-hexane), from crude extract of L. tetragonum were tested for their ability to prevent adipogenesis in differentiating 3T3-L1 preadipocytes. The treatment of differentiating 3T3-L1 preadipocytes with L. tetragonum subfractions (LTFs) resulted in suppressed adipogenesis and reduced expression of adipogenesis-related transcription factors such as peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$), CCAATT/enhancer-binding protein alpha ($C/EBP{\alpha}$), and sterol regulatory element-binding protein 1c (SREBP-1c) at both mRNA and protein levels. In addition, the LTF treatment notably decreased the levels of phosphorylated p38, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK) of the mitogen-activated protein kinase (MAPK) pathway in association with $PPAR{\gamma}$-linked adipogenesis. Among all the tested LTFs, $H_2O$ and n-hexane were the most effective in lowering lipid accumulation and regulating the adipocyte differentiation via $PPAR{\gamma}$ pathway. Taken together, the results indicated that the $H_2O$ and n-hexane LTFs contain bioactive compounds that may exhibit significant antiadipogenesis activity by downregulation of the $PPAR{\gamma}$ pathway and inactivation of the MAPK signal pathway in 3T3-L1 preadipocytes.

• Journal of Korean Medicine Rehabilitation
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• v.26 no.1
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• pp.13-31
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• 2016

Objectives In this study, it was investigated whether Gami-Handayeolso-Tang (HDYST) medication has anti-obesity effects in high fat diet (HFD)-fed obese mice. Methods The experimental animals were divided into five groups-normal diet-fed (ND), high fat diet-fed control (HFD), HFD+HDYST 150, HFD+HDYST 300, and HFD+orlistat as a positive drug. The obese markers such as body weight, diet efficiency ratio, serum levels of total cholesterol, triglyceride, lipid contents, leptin, adiponectin, and GOT/GPT were measured. Also, white adipose tissue, liver weight, abdominal fat mass, hepatic lipid contents, and mRNA expression of obese-associating genes were examined in obese mice. Results In high fat diet-fed mice, HDYST administration significantly decreased body weight, diet efficiency ratio, serum levels of total cholesterol, triglyceride, LDL-cholesterol, as well as leptin and GOT/GPT, compared to the HFD group in a dose-dependent manner. HDYST increased significantly the serum levels of HDL-cholesterol and adiponectin. It also reduced the accumulation of lipids, such as total lipid and triglycerides, in organs such as liver and abdominal adipose tissue. Moreover, HDYST administration significantly decreased the expression levels of fatty acid synthetic genes, such as sterol regulatory element-binding protein-1c (SREBP-1c), FAS and Stearoyl-Coenzyme A desaturase 1 (SCD-1), in the liver tissues, while it increased the messenger RAN (mRNA) levels of fatty acid catalytic genes, such as Peroxisome proliferator activated receptor alpha (PPAR-${\alpha}$), acyl-COA oxidase (ACO), and Carnitine palmitoyltransferase-1a (CPT-1a). Conclusions Based on the results above, HDYST reveals anti-obesity effects declining body fat accumulation through the regulation of fatty acid metabolism and leptin/adiponectin serum levels. It therefore suggests that HDYST can be clinically useful for the treatment of obesity.