Abstract 192: High Fat Diet Promotes Haplotype Dependent Differential Transcriptional Regulation of the Human Angiotensinogen Gene

2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Anita Rana ◽  
Nitin Puri ◽  
Sudhir Jain ◽  
Ashok Kumar
Keyword(s):  
Adipose Tissue ◽  
Transcriptional Regulation ◽  
High Fat Diet ◽  
Control Diet ◽  
Transcriptional Factors ◽  
Antioxidant Defenses ◽  
Diet Change ◽  
High Fat ◽  
Angiotensinogen Gene

Angiotensinogen (AGT) is the only known precursor to angiotensin II. Systemic renin angiotensin aldosterone system (RAAS) is activated in human and experimental models of obesity. RAAS activation in obesity is linked to the development of cardiovascular pathophysiologies. We have identified polymorphisms in 2.5 Kb promoter of human angiotensinogen gene (hAGT) that forms two haplotype (Hap) blocks: -6A/G (-1670A/G, -1562C/T, -1561T/C) and -217A/G (-532T/C, -793A/G, -1074T/C,& -1178G/A). Hap -6A/-217A (Hap -6A) is associated with human hypertension whereas, Hap -6G/-217G (Hap -6G) reduces cardiovascular risk. Here, we examine high fat diet-mediated allele-specific transcriptional regulation of the hAGT gene in adipose tissue, in vivo, in transgenic (TG) mice engineered with either haplotype of the hAGT gene. Twelve-week-old male TG mice with Hap –6A or –6G were fed normal diet (10% kcal as fat) and high fat diet (60% kcal as fat) for 10 weeks. Using Q - RT PCR and western blot we show increased hAGT expression in adipose tissue of the Hap -6A-TG mice after high fat diet than control diet (Hap -6A-0.68±0.04 vs. Hap -6G- 0.33±0.03 A.U., p<0.05). ChIP assay shows greater chromatin binding of GR, MR, CEBPβ and STAT3 transcriptional factors (Hap -6A- 0.80±0.04 vs. Hap -6G- 0.26±0.06 A.U., p<0.05) to the hAGT transgenes in Hap -6A TG mice after high fat diet. No significant change was observed in the endogenous mouse AGT gene. In addition, after high fat diet, change ([[Unable to Display Character: &#8710;]]) in inflammatory and redox markers was significantly (p<0.05) greater in TG mice with Hap I including, IL1 (4.6±0.8 vs. 2.1±0.49 fold), IL6 (4.0±0.69 vs. 2.1±0.2 fold) and NOX1 (8.3±0.4 vs. 2.5±0.6 fold). This is accompanied by reduction in levels of antioxidant defenses (SOD1: 0.97±0.0 vs. 1.4±0.1 fold; HO1: 0.77±0.1 vs. 1.3±0.2 fold) & activation of MAPK14 and ERK1/2 signaling. Taken together, our results show that SNPs in the hAGT Hap -6A favor high fat diet induced binding of transcriptional factors GR, MR, CEBP-β and STAT3 that lead to elevated expression of the hAGT in expanded mass of the adipose tissue. This also activates the RAAS with pathophysiological implications including, phosphorylation of kinases such as MAPK14 and ERK2, increase in tissue pro-inflammatory and oxidative stress molecules.

Abstract 082: High Fat Diet Promotes Haplotype Dependent Differential Transcriptional Regulation of the Human Angiotensinogen Gene

Hypertension ◽  
2015 ◽  
Vol 66 (suppl_1) ◽  
Author(s):  
Anita Rana ◽  
Sudhir Jain ◽  
Nitin Puri ◽  
Deniz Eren ◽  
Natalie Sirianni ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Transcriptional Regulation ◽  
High Fat Diet ◽  
Control Diet ◽  
Transcriptional Factors ◽  
Antioxidant Defenses ◽  
Diet Change ◽  
High Fat ◽  
Angiotensinogen Gene

Angiotensinogen (AGT) is the only known precursor to angiotensin II. Systemic renin angiotensin aldosterone system (RAAS) is activated in human and experimental models of obesity. RAAS activation in obesity is linked to the development of cardiovascular pathophysiologies. We have identified polymorphisms in 2.5 Kb promoter of human angiotensinogen gene (hAGT) that forms two haplotype (Hap) blocks: -6A/G (-1670A/G, -1562C/T, -1561T/C) and -217A/G (-532T/C, -793A/G, -1074T/C,& -1178G/A). Hap -6A/-217A (Hap -6A) is associated with human hypertension whereas, Hap -6G/-217G (Hap -6G) reduces cardiovascular risk. Here, we examine high fat diet-mediated allele-specific transcriptional regulation of the hAGT gene in adipose tissue, in vivo, in transgenic (TG) mice engineered with either haplotype of the hAGT gene. Twelve-week-old male TG mice with Hap –6A or –6G were fed normal diet (10% kcal as fat) and high fat diet (60% kcal as fat) for 10 weeks. Using Q - RT PCR and western blot we show increased hAGT expression in adipose tissue of the Hap -6A-TG mice after high fat diet than control diet (Hap -6A-0.68±0.04 vs. Hap -6G- 0.33±0.03 A.U., p<0.05). ChIP assay shows greater chromatin binding of GR, MR, CEBPβ and STAT3 transcriptional factors (Hap -6A- 0.80±0.04 vs. Hap -6G- 0.26±0.06 A.U., p<0.05) to the hAGT transgenes in Hap -6A TG mice after high fat diet. No significant change was observed in the endogenous mouse AGT gene. In addition, after high fat diet, change ([[Unable to Display Character: &#8710;]]) in inflammatory and redox markers was significantly (p<0.05) greater in TG mice with Hap I including, IL1 (4.6±0.8 vs. 2.1±0.49 fold), IL6 (4.0±0.69 vs. 2.1±0.2 fold) and NOX1 (8.3±0.4 vs. 2.5±0.6 fold). This is accompanied by reduction in levels of antioxidant defenses (SOD1: 0.97±0.0 vs. 1.4±0.1 fold; HO1: 0.77±0.1 vs. 1.3±0.2 fold) & activation of MAPK14 and ERK1/2 signaling. Taken together, our results show that SNPs in the hAGT Hap -6A favor high fat diet induced binding of transcriptional factors GR, MR, CEBP-β and STAT3 that lead to elevated expression of the hAGT in expanded mass of the adipose tissue. This also activates the RAAS with pathophysiological implications including, phosphorylation of kinases such as MAPK14 and ERK2, increase in tissue pro-inflammatory and oxidative stress molecules.

scholarly journals The Role of Perivascular Adipose Tissue in Early Changes in Arterial Function during High-Fat Diet and Its Combination with High-Fructose Intake in Rats

Biomedicines ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1552
Author(s):  
Jozef Torok ◽  
Anna Zemancikova ◽  
Zuzana Valaskova ◽  
Peter Balis
Keyword(s):  
Adipose Tissue ◽  
High Fat Diet ◽  
Control Diet ◽  
Sympathetic Nerves ◽  
High Fat ◽  
Perivascular Adipose Tissue ◽  
Fructose Intake ◽  
High Fructose ◽  
Wistar Kyoto ◽  
Isolated Arteries

The aim of the current study was to evaluate the influence of a high-fat diet and its combination with high-fructose intake on young normotensive rats, with focus on the modulatory effect of perivascular adipose tissue (PVAT) on the reactivity of isolated arteries. Six-week-old Wistar–Kyoto rats were treated for 8 weeks with a control diet (10% fat), a high-fat diet (HFD; 45% fat), or a combination of the HFD with a 10% solution of fructose. Contractile and relaxant responses of isolated rat arteries, with preserved and removed PVAT for selected vasoactive stimuli, were recorded isometrically by a force displacement transducer. The results demonstrated that, in young rats, eight weeks of the HFD might lead to body fat accumulation and early excitation of the cardiovascular sympathetic nervous system, as shown by increased heart rate and enhanced arterial contractile responses induced by endogenous noradrenaline released from perivascular sympathetic nerves. The addition of high-fructose intake deteriorated this state by impairment of arterial relaxation and resulted in mild elevation of systolic blood pressure; however, the increase in arterial neurogenic contractions was not detected. The diet-induced alterations in isolated arteries were observed only in the presence of PVAT, indicating that this structure is important in initiation of early vascular changes during the development of metabolic syndrome.

scholarly journals Browning Effects of a Chronic Pterostilbene Supplementation in Mice Fed a High-Fat Diet

2019 ◽  
Vol 20 (21) ◽  
pp. 5377 ◽  
Author(s):  
Martina La Spina ◽  
Eva Galletta ◽  
Michele Azzolini ◽  
Saioa Gomez Zorita ◽  
Sofia Parrasia ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
White Adipose Tissue ◽  
High Fat Diet ◽  
Uncoupling Protein ◽  
Protein A ◽  
Health Concern ◽  
Marker Genes ◽  
High Fat ◽  
Protein Levels

Obesity and related comorbidities are a major health concern. The drugs used to treat these conditions are largely inadequate or dangerous, and a well-researched approach based on nutraceuticals would be highly useful. Pterostilbene (Pt), i.e., 3,5-dimethylresveratrol, has been reported to be effective in animal models of obesity, acting on different metabolic pathways. We investigate here its ability to induce browning of white adipose tissue. Pt (5 µM) was first tested on 3T3-L1 mature adipocytes, and then it was administered (352 µmol/kg/day) to mice fed an obesogenic high-fat diet (HFD) for 30 weeks, starting at weaning. In the cultured adipocytes, the treatment elicited a significant increase of the levels of Uncoupling Protein 1 (UCP1) protein—a key component of thermogenic, energy-dissipating beige/brown adipocytes. In vivo administration antagonized weight increase, more so in males than in females. Analysis of inguinal White Adipose Tissue (WAT) revealed a trend towards browning, with significantly increased transcription of several marker genes (Cidea, Ebf2, Pgc1α, PPARγ, Sirt1, and Tbx1) and an increase in UCP1 protein levels, which, however, did not achieve significance. Given the lack of known side effects of Pt, this study strengthens the candidacy of this natural phenol as an anti-obesity nutraceutical.

scholarly journals Oleacein Prevents High Fat Diet-Induced A Diposity and Ameliorates Some Biochemical Parameters of Insulin Sensitivity in Mice

Nutrients ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1829 ◽  
Author(s):  
Lepore ◽  
Maggisano ◽  
Bulotta ◽  
Mignogna ◽  
Arcidiacono ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Adipose Tissue ◽  
Insulin Sensitivity ◽  
High Fat Diet ◽  
Fatty Acid Synthase ◽  
Glucose Transporter ◽  
Regulatory Element ◽  
Regulatory Elements ◽  
High Fat

Oleacein is one of the most abundant polyphenolic compounds of olive oil, which has been shown to play a protective role against several metabolic abnormalities, including dyslipidemia, insulin resistance, and glucose intolerance. Herein, we investigated the effects of oleacein on certain markers of adipogenesis and insulin-resistance in vitro, in 3T3-L1 adipocytes, and in vivo in high-fat diet (HFD)-fed mice. During the differentiation process of 3T3-L1 preadipocytes into adipocytes, oleacein strongly inhibited lipid accumulation, and decreased protein levels of peroxisome proliferator-activated receptor gamma (PPARγ) and fatty acid synthase (FAS), while increasing Adiponectin levels. In vivo, treatment with oleacein of C57BL/6JOlaHsd mice fed with HFD for 5 and 13 weeks prevented the increase in adipocyte size and reduced the inflammatory infiltration of macrophages and lymphocytes in adipose tissue. These effects were accompanied by changes in the expression of adipose tissue-specific regulatory elements such as PPARγ, FAS, sterol regulatory element-binding transcription factor-1 (SREBP-1), and Adiponectin, while the expression of insulin-sensitive muscle/fat glucose transporter Glut-4 was restored in HFD-fed mice treated with oleacein. Collectively, our findings indicate that protection against HFD-induced adiposity by oleacein in mice is mediated by the modulation of regulators of adipogenesis. Protection against HFD-induced obesity is effective in improving peripheral insulin sensitivity.

Effect of a high-fat diet on the incorporation of stored triacylglycerol into hepatic VLDL

1992 ◽  
Vol 263 (4) ◽  
pp. E615-E623 ◽  
Author(s):  
O. L. Francone ◽  
G. Griffaton ◽  
A. D. Kalopissis
Keyword(s):  
Endoplasmic Reticulum ◽  
High Fat Diet ◽  
Lipid Droplets ◽  
Control Diet ◽  
Oxidation Products ◽  
High Fat ◽  
Very Low Density Lipoproteins ◽  
Total Utilization ◽  
Fat Feeding

Triacylglycerol (TG) stored in cytoplasmic lipid droplets of hepatocytes was labeled by in vivo [1-(14)C]oleic acid injection to study the effect of a high-fat diet on its incorporation into very-low-density lipoproteins (VLDL). Compared with the control diet, hepatocytes of fat-fed rats 1) contained 7.6 times more cytoplasmic (floating fat) TG and 1.9 times more endoplasmic reticulum (microsomal) TG; 2) had 8 and 6 times lower TG specific activities in cytoplasm and endoplasmic reticulum, respectively; 3) incorporated 22% less 14C label into hepatocyte esterified lipids (TG, cholesterol, phospholipid); 4) secreted 48 and 33% less radioactive and total VLDL-TG, respectively; 5) oxidized more cytoplasmic TG-fatty acid (FA); and 6) showed a 50% decreased total utilization of stored TG-FA. With both diets, the lysosomal inhibitor chloroquine concomitantly decreased productions of labeled VLDL-TG, CO2, and acid-soluble oxidation products. The decreased incorporation of stored TG into VLDL-TG appreciably contributes to the overall inhibition of hepatic VLDL secretion by fat feeding. It appears to be related to the decreased mobilization rate of stored TG and its increased channelling toward oxidation.

scholarly journals High fat diet induces dysregulation of hepatic oxygen gradients and mitochondrial function in vivo

2008 ◽  
Vol 417 (1) ◽  
pp. 183-193 ◽  
Author(s):  
Sudheer K. Mantena ◽  
Denty Paul Vaughn ◽  
Kelly K. Andringa ◽  
Heather B. Eccleston ◽  
Adrienne L. King ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
High Fat Diet ◽  
Protein Modification ◽  
Control Diet ◽  
Critical Role ◽  
Liver Mitochondria ◽  
Mitochondrial Proteins ◽  
High Fat ◽  
Alcoholic Fatty Liver

NAFLD (non-alcoholic fatty liver disease), associated with obesity and the cardiometabolic syndrome, is an important medical problem affecting up to 20% of western populations. Evidence indicates that mitochondrial dysfunction plays a critical role in NAFLD initiation and progression to the more serious condition of NASH (non-alcoholic steatohepatitis). Herein we hypothesize that mitochondrial defects induced by exposure to a HFD (high fat diet) contribute to a hypoxic state in liver and this is associated with increased protein modification by RNS (reactive nitrogen species). To test this concept, C57BL/6 mice were pair-fed a control diet and HFD containing 35% and 71% total calories (1 cal≈4.184 J) from fat respectively, for 8 or 16 weeks and liver hypoxia, mitochondrial bioenergetics, NO (nitric oxide)-dependent control of respiration, and 3-NT (3-nitrotyrosine), a marker of protein modification by RNS, were examined. Feeding a HFD for 16 weeks induced NASH-like pathology accompanied by elevated triacylglycerols, increased CYP2E1 (cytochrome P450 2E1) and iNOS (inducible nitric oxide synthase) protein, and significantly enhanced hypoxia in the pericentral region of the liver. Mitochondria from the HFD group showed increased sensitivity to NO-dependent inhibition of respiration compared with controls. In addition, accumulation of 3-NT paralleled the hypoxia gradient in vivo and 3-NT levels were increased in mitochondrial proteins. Liver mitochondria from mice fed the HFD for 16 weeks exhibited depressed state 3 respiration, uncoupled respiration, cytochrome c oxidase activity, and mitochondrial membrane potential. These findings indicate that chronic exposure to a HFD negatively affects the bioenergetics of liver mitochondria and this probably contributes to hypoxic stress and deleterious NO-dependent modification of mitochondrial proteins.

scholarly journals CTRP9 transgenic mice are protected from diet-induced obesity and metabolic dysfunction

2013 ◽  
Vol 305 (5) ◽  
pp. R522-R533 ◽  
Author(s):  
Jonathan M. Peterson ◽  
Zhikui Wei ◽  
Marcus M. Seldin ◽  
Mardi S. Byerly ◽  
Susan Aja ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Adipose Tissue ◽  
Transgenic Mice ◽  
High Fat Diet ◽  
Fat Oxidation ◽  
Acid Oxidation ◽  
Ampk Activation ◽  
High Fat ◽  
Diet Induced Obesity

CTRP9 is a secreted multimeric protein of the C1q family and the closest paralog of the insulin-sensitizing adipokine, adiponectin. The metabolic function of this adipose tissue-derived plasma protein remains largely unknown. Here, we show that the circulating levels of CTRP9 are downregulated in diet-induced obese mice and upregulated upon refeeding. Overexpressing CTRP9 resulted in lean mice that dramatically resisted weight gain induced by a high-fat diet, largely through decreased food intake and increased basal metabolism. Enhanced fat oxidation in CTRP9 transgenic mice resulted from increases in skeletal muscle mitochondrial content, expression of enzymes involved in fatty acid oxidation (LCAD and MCAD), and chronic AMPK activation. Hepatic and skeletal muscle triglyceride levels were substantially decreased in transgenic mice. Consequently, CTRP9 transgenic mice had a greatly improved metabolic profile with markedly reduced fasting insulin and glucose levels. The high-fat diet-induced obesity, insulin resistance, and hepatic steatosis observed in wild-type mice were prevented in transgenic mice. Consistent with the in vivo data, recombinant protein significantly enhanced fat oxidation in L6 myotubes via AMPK activation and reduced lipid accumulation in H4IIE hepatocytes. Collectively, these data establish CTRP9 as a novel metabolic regulator and a new component of the metabolic network that links adipose tissue to lipid metabolism in skeletal muscle and liver.

scholarly journals Cytochrome P-450 CYP2E1 knockout mice are protected against high-fat diet-induced obesity and insulin resistance

2012 ◽  
Vol 302 (5) ◽  
pp. E532-E539 ◽  
Author(s):  
Haihong Zong ◽  
Michal Armoni ◽  
Chava Harel ◽  
Eddy Karnieli ◽  
Jeffrey E. Pessin
Keyword(s):  
Insulin Resistance ◽  
Adipose Tissue ◽  
Knockout Mice ◽  
High Fat Diet ◽  
Whole Body ◽  
High Fat ◽  
Normal Chow ◽  
Glucose Output ◽  
Fat Diets

Conventional (whole body) CYP2E1 knockout mice displayed protection against high-fat diet-induced weight gain, obesity, and hyperlipidemia with increased energy expenditure despite normal food intake and spontaneous locomotor activity. In addition, the CYP2E1 knockout mice displayed a marked improvement in glucose tolerance on both normal chow and high-fat diets. Euglycemic-hyperinsulinemic clamps demonstrated a marked protection against high-fat diet-induced insulin resistance in CYP2E1 knockout mice, with enhanced adipose tissue glucose uptake and insulin suppression of hepatic glucose output. In parallel, adipose tissue was protected against high-fat diet-induced proinflammatory cytokine production. Taken together, these data demonstrate that the CYP2E1 deletion protects mice against high-fat diet-induced insulin resistance with improved glucose homeostasis in vivo.

scholarly journals Macadamia Oil Supplementation Attenuates Inflammation and Adipocyte Hypertrophy in Obese Mice

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Edson A. Lima ◽  
Loreana S. Silveira ◽  
Laureane N. Masi ◽  
Amanda R. Crisma ◽  
Mariana R. Davanso ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Insulin Sensitivity ◽  
Lipid Profile ◽  
High Fat Diet ◽  
Control Diet ◽  
Saturated Fatty Acids ◽  
Peritoneal Macrophages ◽  
High Fat ◽  
Obesity In Mice ◽  
Adipocyte Hypertrophy

Excess of saturated fatty acids in the diet has been associated with obesity, leading to systemic disruption of insulin signaling, glucose intolerance, and inflammation. Macadamia oil administration has been shown to improve lipid profile in humans. We evaluated the effect of macadamia oil supplementation on insulin sensitivity, inflammation, lipid profile, and adipocyte size in high-fat diet (HF) induced obesity in mice. C57BL/6 male mice (8 weeks) were divided into four groups: (a) control diet (CD), (b) HF, (c) CD supplemented with macadamia oil by gavage at 2 g/Kg of body weight, three times per week, for 12 weeks (CD + MO), and (d) HF diet supplemented with macadamia oil (HF + MO). CD and HF mice were supplemented with water. HF mice showed hypercholesterolemia and decreased insulin sensitivity as also previously shown. HF induced inflammation in adipose tissue and peritoneal macrophages, as well as adipocyte hypertrophy. Macadamia oil supplementation attenuated hypertrophy of adipocytes and inflammation in the adipose tissue and macrophages.

scholarly journals An ethanolic extract of Artemisia scoparia inhibits lipolysis in vivo and has antilipolytic effects on murine adipocytes in vitro

2018 ◽  
Vol 315 (5) ◽  
pp. E1053-E1061 ◽  
Author(s):  
Anik Boudreau ◽  
Allison J. Richard ◽  
Jasmine A. Burrell ◽  
William T. King ◽  
Ruth Dunn ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Microarray Analysis ◽  
High Fat Diet ◽  
Ethanolic Extract ◽  
High Fat ◽  
Artemisia Scoparia

An ethanolic extract of Artemisia scoparia (SCO) has metabolically favorable effects on adipocyte development and function in vitro and in vivo. In diet-induced obese mice, SCO supplementation significantly reduced fasting glucose and insulin levels. Given the importance of adipocyte lipolysis in metabolic health, we hypothesized that SCO modulates lipolysis in vitro and in vivo. Free fatty acids and glycerol were measured in the sera of mice fed a high-fat diet with or without SCO supplementation. In cultured 3T3-L1 adipocytes, the effects of SCO on lipolysis were assessed by measuring glycerol and free fatty acid release. Microarray analysis, qPCR, and immunoblotting were used to assess gene expression and protein abundance. We found that SCO supplementation of a high-fat diet in mice substantially reduces circulating glycerol and free fatty acid levels, and we observed a cell-autonomous effect of SCO to significantly attenuate tumor necrosis factor-α (TNFα)-induced lipolysis in cultured adipocytes. Although several prolipolytic and antilipolytic genes were identified by microarray analysis of subcutaneous and visceral adipose tissue from SCO-fed mice, regulation of these genes did not consistently correlate with SCO’s ability to reduce lipolytic metabolites in sera or cell culture media. However, in the presence of TNFα in cultured adipocytes, SCO induced antilipolytic changes in phosphorylation of hormone-sensitive lipase and perilipin. Together, these data suggest that the antilipolytic effects of SCO on adipose tissue play a role in the ability of this botanical extract to improve whole body metabolic parameters and support its use as a dietary supplement to promote metabolic resiliency.

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