PURPOSE: Obesity is a major health problem of global significance because it is clearly associated with an increased risk of health problems, such as nonalcoholic fatty liver disease (NAFLD), diabetes, cardiovascular diseases, and cancer. Lonicera caerulea (LC) originates from high mountains or wet areas and has been used as a traditional medicine in northern Russia, China, and Japan. LC contains a range of bioactive constituents, such as vitamins, minerals, and polyphenols. This study examined the anti-obesity effects of LC during differentiation in preadipocytes. METHODS: The cell viability assay was performed after the differentiation of 3T3-L1 cells for 7 days. Oil Red O staining was used to visualize the changes in lipid droplets in 3T3-L1 cells and mouse adipose-derived stem cells (MADSCs). The mRNA expression of obesity-related genes was determined by quantitative real-time PCR. RESULTS: According to the results of Oil Red O staining, the lipid levels and size of lipid droplets in the adipocytes were reduced and the LC extract (LCE, 0.25–1 mg/mL) markedly inhibited adipogenesis in a dose-dependent manner. The treatment of LCE also decreased the mRNA expression of peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer binding protein-α (C/EBPα), and sterol regulatory element binding protein 1 (SREBP1) in 3T3-L1 cells. Western blot analysis showed that the PPARγ, C/EBPα, and SREBP1 protein levels in both 3T3-L1 and MADSC were reduced in a dose-dependent manner. CONCLUSION: These results suggest that LCE can inhibit adipogenic differentiation through the regulation of adipogenesis-related markers.
3T3-L1 Cells ; Adipocytes ; Adipogenesis ; Animals ; Blotting, Western ; Cardiovascular Diseases ; Cell Survival ; China ; Japan ; Lipid Droplets ; Lonicera ; Medicine, Traditional ; Mice ; Minerals ; Miners ; Non-alcoholic Fatty Liver Disease ; Obesity ; Peroxisomes ; Polyphenols ; Real-Time Polymerase Chain Reaction ; RNA, Messenger ; Russia ; Stem Cells ; Sterol Regulatory Element Binding Protein 1 ; Vitamins

BACKGROUND/OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) is a common metabolic disease triggered by epigenetic alterations, including lysine acetylation at histone or non-histone proteins, affecting the stability or transcription of lipogenic genes. Although various natural dietary compounds have anti-lipogenic effects, their effects on the acetylation status and lipid metabolism in the liver have not been thoroughly investigated. MATERIALS/METHODS: Following oleic-palmitic acid (OPA)-induced lipid accumulation in HepG2 cells, the acetylation status of histone and non-histone proteins, HAT activity, and mRNA expression of representative lipogenic genes, including PPARγ, SREBP-1c, ACLY, and FASN, were evaluated. Furthermore, correlations between lipid accumulation and HAT activity for 22 representative natural food extracts (NExs) were evaluated. RESULTS: Non-histone protein acetylation increased following OPA treatment and the acetylation of histones H3K9, H4K8, and H4K16 was accelerated, accompanied by an increase in HAT activity. OPA-induced increases in the mRNA expression of lipogenic genes were down-regulated by C-646, a p300/CBP-specific inhibitor. Finally, we detected a positive correlation between HAT activity and lipid accumulation (Pearson's correlation coefficient = 0.604) using 22 NExs. CONCLUSIONS: Our results suggest that NExs have novel applications as nutraceutical agents with HAT inhibitor activity for the prevention and treatment of NAFLD.
Acetylation ; Dietary Supplements ; Epigenomics ; Hep G2 Cells ; Histone Acetyltransferases ; Histones ; Lipid Metabolism ; Lipogenesis ; Liver ; Lysine ; Metabolic Diseases ; Non-alcoholic Fatty Liver Disease ; RNA, Messenger ; Sterol Regulatory Element Binding Protein 1

The aim of this study was to explore the effect of emodin on lipid accumulation and inflammation in hepatocytes. The cell morphology was observed by microscopy. LDH release was detected by the kit. Levels of intracellular lipid droplets were observed by oil red O staining. The contents of TC and TG in cells were detected by the kit. Western blot was used to determine protein expressions of FASN,SREBF2,APOB,IL-6 and p-NF-κB in hepatocytes. The results showed that the levels of L02 cell LDH were significantly increased after being treated with emodin,and the cells showed shrinkage,volume reduction,decrease in quantity with the increase of dose. Red lipid droplets were observed in L02 hepatocytes. Intracellular TC and TG contents of L02 cell increased in a concentrationdependent manner,with significant differences between medium and high-dose groups( P < 0. 05). Protein expressions of FASN,SREBF2,IL-6 and p-NF-κB were significantly higher than those of the control group,and the expression level of APOB was significantly lower than that of the control group( P<0. 05). In conclusion,emodin could induce lipid accumulation and inflammatory damage in hepatocytes in a dose-dependent manner,which in turn could damage liver cells. This process was related to the up-regulation of FASN,SREBF2,IL-6,p-NF-κB,as well as the down-regulation of the protein expression of APOB.
Apolipoprotein B-100 ; metabolism ; Cells, Cultured ; Emodin ; pharmacology ; Fatty Acid Synthase, Type I ; metabolism ; Hepatocytes ; drug effects ; metabolism ; Humans ; Inflammation ; Interleukin-6 ; metabolism ; Lipid Metabolism ; Lipids ; NF-kappa B ; metabolism ; Sterol Regulatory Element Binding Protein 2 ; metabolism

The aim of this paper was to investigate the molecular mechanism of Calculus Bovis Sativus( CBS) in alleviating lipid accumulation in vitro by serum pharmacology. The CBS-containing serum of mice was obtained by serum pharmacology method to evaluate its effect on the proliferation of LO2 hepatocytes. The lipid reducing effects of CBS-containing serum through Nrf2 was evaluated by fructose-induced LO2 hepatocyte steatosis model,nuclear factor erythroid 2 related factor 2( Nrf2) agonist oltipraz combined intervention,cell oil red O staining and intracellular triglyceride( TG) content. The effects of CBS-containing serum on lipid peroxidation and hepatocytes apoptosis were evaluated by reactive oxygen species( ROS) and apoptosis assay,respectively. Real-time quantitative polymerase chain reaction( PCR) was used to detect the relative expression of lipid synthesis-related genes and apoptosis-related genes.RESULTS:: showed that CBS drug-containing serum had no significant effect on LO2 hepatocyte proliferation. As compared with the model group,CBS-containing serum could effectively reduce the formation of lipid droplets in fructose-induced LO2 hepatocytes,significantly reduce intracellular TG and ROS levels,and significantly reduce hepatocyte apoptosis rate( P < 0. 05). As compared with the model group,carbohydrate responsive element binding protein( ChREBP),sterol regulatory element binding protein-1 c( SREBP-1 c),fatty acid synthase( FAS),acetyl-CoA carboxylase 1( ACC1),stearoyl-CoA desaturase 1( SCD1),Bax and caspase-3 mRNA levels were significantly reduced in CBS drug-containing serum treatment group( P<0. 05). All of the above effects could be reversed by oltipraz.In conclusion,CBS-containing serum can significantly inhibit the fructose-induced LO2 liver fat deposition,and the mechanism may be related to reducing intracellular ROS level through the Nrf2 pathway and improving intracellular peroxidation state to reduce apoptosis.
Animals ; Apoptosis ; Cattle ; Cells, Cultured ; Fatty Liver ; Fructose ; Gallstones ; chemistry ; Hepatocytes ; cytology ; metabolism ; Lipid Metabolism ; Lipid Peroxidation ; Liver ; Medicine, Chinese Traditional ; Mice ; Reactive Oxygen Species ; metabolism ; Serum ; chemistry ; Sterol Regulatory Element Binding Protein 1 ; metabolism ; Triglycerides

BackgroundA high consumption of fructose leads to hepatic steatosis. About 20-30% of triglycerides are synthesized via de novo lipogenesis. Some studies showed that endoplasmic reticulum stress (ERS) is involved in this process, while others showed that a lipotoxic environment directly influences ER homeostasis. Here, our aim was to investigate the causal relationship between ERS and fatty acid synthesis and the effect of X-box binding protein-1 (XBP-1), one marker of ERS, on hepatic lipid accumulation stimulated by high fructose.

MethodsHepG2 cells were incubated with different concentrations of fructose. Upstream regulators of de novo lipogenesis (i.e., carbohydrate response element-binding protein [ChREBP] and sterol regulatory element-binding protein 1c [SREBP-1c]) were measured by polymerase chain reaction and key lipogenic enzymes (acetyl-CoA carboxylase [ACC], fatty acid synthase [FAS], and stearoyl-CoA desaturase-1 [SCD-1]) by Western blotting. The same lipogenesis-associated factors were then evaluated after exposure of HepG2 cells to high fructose followed by the ERS inhibitor tauroursodeoxycholic acid (TUDCA) or the ERS inducer thapsigargin. Finally, the same lipogenesis-associated factors were evaluated in HepG2 cells after XBP-1 upregulation or downregulation through cell transfection.

ResultsExposure to high fructose increased triglyceride levels in a dose- and time-dependent manner and significantly increased mRNA levels of SREBP-1c and ChREBP and protein levels of FAS, ACC, and SCD-1, concomitant with XBP-1 conversion to an active spliced form. Lipogenesis-associated factors induced by high fructose were inhibited by TUDCA and induced by thapsigargin. Triglyceride level in XBP-1-deficient group decreased significantly compared with high-fructose group (4.41 ± 0.54 μmol/g vs. 6.52 ± 0.38 μmol/g, P < 0.001), as mRNA expressions of SREBP-1c (2.92 ± 0.46 vs. 5.08 ± 0.41, P < 0.01) and protein levels of FAS (0.53 ± 0.06 vs. 0.85 ± 0.05, P = 0.01), SCD-1 (0.65 ± 0.06 vs. 0.90 ± 0.04, P = 0.04), and ACC (0.38 ± 0.03 vs. 0.95 ± 0.06, P < 0.01) decreased. Conversely, levels of triglyceride (4.22 ± 0.54 μmol/g vs. 2.41 ± 0.35 μmol/g, P < 0.001), mRNA expression of SREBP-1c (2.70 ± 0.33 vs. 1.00 ± 0.00, P < 0.01), and protein expression of SCD-1 (0.93 ± 0.06 vs. 0.26 ± 0.05, P < 0.01), ACC (0.98 ± 0.09 vs. 0.43 ± 0.03, P < 0.01), and FAS (0.90 ± 0.33 vs. 0.71 ± 0.02, P = 0.04) in XBP-1s-upregulated group increased compared with the untransfected group.

ConclusionsERS is associated with de novo lipogenesis, and XBP-1 partially mediates high-fructose-induced lipid accumulation in HepG2 cells through augmentation of de novo lipogenesis.

Endoplasmic Reticulum Stress ; physiology ; Fatty Liver ; Fructose ; metabolism ; Hep G2 Cells ; Humans ; Lipogenesis ; physiology ; Liver ; Sterol Regulatory Element Binding Protein 1 ; X-Box Binding Protein 1 ; physiology

Obesity is currently one of the most serious public health problems and it can lead to numerous metabolic diseases. Leucrose, d-glucopyranosyl-α-(1-5)-d-fructopyranose, is an isoform of sucrose and it is naturally found in pollen and honey. The aim of this study was to investigate the effect of leucrose on metabolic changes induced by a high-fat diet (HFD) that lead to obesity. C57BL/6 mice were fed a 60% HFD or a HFD with 25% (L25) or 50% (L50) of its total sucrose content replaced with leucrose for 12 weeks. Leucrose supplementation improved fasting blood glucose levels and hepatic triglyceride content. In addition, leucrose supplementation reduced mRNA levels of lipogenesis-related genes, including peroxisome proliferator-activated receptor γ, sterol regulatory element binding protein 1C, and fatty acid synthase in HFD mice. Conversely, mRNA levels of β oxidation-related genes, such as carnitine palmitoyltransferase 1A and acyl CoA oxidase, returned to control levels with leucrose supplementation. Taken together, these results demonstrated the therapeutic potential of leucrose to prevent metabolic abnormalities by mediating regulation of plasma glucose level and hepatic triglyceride accumulation.
Acyl-CoA Oxidase ; Animals ; Blood Glucose ; Carnitine O-Palmitoyltransferase ; Diet, High-Fat ; Fasting ; Honey ; Lipogenesis ; Liver ; Metabolic Diseases ; Mice ; Mice, Obese ; Negotiating ; Obesity ; Peroxisomes ; Pollen ; Public Health ; RNA, Messenger ; Sterol Regulatory Element Binding Protein 1 ; Sucrose ; Triglycerides

BACKGROUND/AIMS: Hepatic steatosis is caused by an imbalance between free fatty acids (FFAs) uptake, utilization, storage, and disposal. Understanding the molecular mechanisms involved in FFAs accumulation and its modulation could drive the development of potential therapies for Nonalcoholic fatty liver disease. The aim of the current study was to explore the effects of picroside II, a phytoactive found in Picrorhiza kurroa, on fatty acid accumulation vis-à-vis silibinin, a known hepatoprotective phytoactive from Silybum marianum. METHODS: HepG2 cells were loaded with FFAs (oleic acid:palmitic acid/2:1) for 20 hours to mimic hepatic steatosis. The FFAs concentration achieving maximum fat accumulation and minimal cytotoxicity (500 μM) was standardized. HepG2 cells were exposed to the standardized FFAs concentration with and without picroside II pretreatment. RESULTS: Picroside II pretreatment inhibited FFAs-induced lipid accumulation by attenuating the expression of fatty acid transport protein 5, sterol regulatory element binding protein 1 and stearoyl CoA desaturase. Preatreatment with picroside II was also found to decrease the expression of forkhead box protein O1 and phosphoenolpyruvate carboxykinase. CONCLUSIONS: These findings suggest that picroside II effectively attenuated fatty acid accumulation by decreasing FFAs uptake and lipogenesis. Picroside II also decreased the expression of gluconeogenic genes.
Fatty Acid Transport Proteins ; Fatty Acids, Nonesterified ; Hep G2 Cells* ; Lipogenesis ; Milk Thistle ; Non-alcoholic Fatty Liver Disease ; Phosphoenolpyruvate ; Picrorhiza ; Stearoyl-CoA Desaturase ; Sterol Regulatory Element Binding Protein 1

BACKGROUND/OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) is a leading cause of chronic liver disease and is closely associated with metabolic syndrome. In the present study, we observed the effect of ethanol extract of Allium fistulosum (EAF) on NAFLD and have suggested the possibility of using EAF as a natural product for application in the development of a treatment for NAFLD. MATERIALS/METHODS: The preventive effect on hepatic lipid accumulation was estimated by using an oleic acid (OA)-induced NAFLD model in vitro and a Western diet (high-fat high-sucrose; WD)-induced obese mouse model. Animals were divided into three groups (n = 7): normal diet group (ND), WD group, and WD plus 1% EAF group. RESULTS: EAF reduced OA-stimulated lipid accumulation in HepG2 cells in the absence of cellular cytotoxicity and significantly blocked transcriptional activation of sterol regulatory element-binding protein 1 and fatty acid synthase genes. Subsequently, we investigated these effects in vivo in mice fed either ND or WD in the presence or absence of EAF supplementation. In comparison to the ND controls, the WD-fed mice exhibited increases in body weight, liver weight, epididymal fat weight, and accumulation of fat in hepatocytes, and these effects were significantly attenuated by EAF supplementation. CONCLUSIONS: Allium fistulosum attenuates the development of NAFLD, and EAF elicits anti-lipogenic activity in liver. Therefore, EAF represents a promising candidate for use in the development of novel therapeutic drugs or drug combinations for the prevention and treatment of NAFLD.
Allium* ; Animals ; Body Weight ; Diet ; Diet, Western ; Drug Combinations ; Ethanol* ; Hep G2 Cells ; Hepatocytes ; In Vitro Techniques ; Lipogenesis ; Liver ; Liver Diseases ; Mice ; Mice, Obese ; Non-alcoholic Fatty Liver Disease* ; Oleic Acid ; Sterol Regulatory Element Binding Protein 1 ; Transcriptional Activation

Animals ; Fasting ; metabolism ; Membrane Proteins ; metabolism ; Mice ; Sterol Regulatory Element Binding Protein 1 ; metabolism ; Transcription Factors ; deficiency ; metabolism

BACKGROUND/OBJECTIVES: Reducing the number of adipocytes by inducing apoptosis of mature adipocytes as well as suppressing differentiation of preadipocytes plays an important role in preventing obesity. This study examines the anti-adipogenic and pro-apoptotic effect of red pepper seed water extract (RPS) prepared at 4℃ (RPS4) in 3T3-L1 cells. MATERIALS/METHODS: Effect of RPS4 or its fractions on lipid accumulation was determined in 3T3-L1 cells using oil red O (ORO) staining. The expressions of AMP-activated protein kinase (AMPK) and adipogenic associated proteins [peroxisome proliferator-activated receptor-γ (PPAR-γ), CCAAT/enhancer-binding proteins α (C/EBP α), sterol regulatory element binding protein-1c (SREBP-1c), fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC)] were measured in 3T3-L1 cells treated with RPS4. Apoptosis and the expression of Akt and Bcl-2 family proteins [B-cell lymphoma 2 (Bcl-2), Bcl-2-associated death promoter (Bad), Bcl-2 like protein 4 (Bax), Bal-2 homologous antagonist/killer (Bak)] were measured in mature 3T3-L1 cells treated with RPS4. RESULTS: Treatment of RPS4 (0–75 µg/mL) or its fractions (0–50 µg/mL) for 24 h did not have an apparent cytotoxicity on pre and mature 3T3-L1 cells. RPS4 significantly suppressed differentiation and cellular lipid accumulation by increasing the phosphorylation of AMPK and reducing the expression of PPAR-γ, C/EBP α, SREBP-1c, FAS, and ACC. In addition, all fractions except ethyl acetate fraction significantly suppressed cellular lipid accumulation. RPS4 induced the apoptosis of mature adipocytes by hypophosphorylating Akt, increasing the expression of the pro-apoptotic proteins, Bak, Bax, and Bad, and reducing the expression of the anti-apoptotic proteins, Bcl-2 and p-Bad. CONCLUSIONS: These finding suggest that RPS4 can reduce the numbers as well as the size of adipocytes and might useful for preventing and treating obesity.
3T3-L1 Cells* ; Acetyl-CoA Carboxylase ; Adipocytes* ; Adipogenesis ; AMP-Activated Protein Kinases ; Apoptosis Regulatory Proteins ; Apoptosis* ; Capsicum* ; Humans ; Lipid Metabolism ; Lymphoma ; Obesity ; Phosphorylation ; Sterol Regulatory Element Binding Protein 1 ; Water*