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In vitro and in vivo enhancement of adipogenesis by Italian ryegrass (Lolium multiflorum) in 3T3-L1 cells and mice. PLoS One 2014; 9:e85297. [PMID: 24454838 PMCID: PMC3890303 DOI: 10.1371/journal.pone.0085297] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2013] [Accepted: 11/25/2013] [Indexed: 12/21/2022] Open
Abstract
Adipogenesis is very much important in improving the quality of meat in animals. The aim of the present study was to investigate the in vitro and in vivo adipogenesis regulation properties of Lolium multiflorum on 3T3-L1 pre-adipocytes and mice. Chemical composition of petroleum ether extract of L. multiflorum (PET-LM) confirmed the presence of fatty acids, such as α-linolenic acid, docosahexaenoic acid, oleic acid, docosatetraenoic acid, and caprylic acid, as the major compounds. PET-LM treatment increased viability, lipid accumulation, lipolysis, cell cycle progression, and DNA synthesis in the cells. PET-LM treatment also augmented peroxysome proliferator activated receptor (PPAR)-γ2, CCAAT/enhancer binding protein-α, adiponectin, adipocyte binding protein, glucose transporter-4, fatty acid synthase, and sterol regulatory element binding protein-1 expression at mRNA and protein levels in differentiated adipocytes. In addition, mice administered with 200 mg/kg body weight PET-LM for 8 weeks showed greater body weight than control mice. These findings suggest that PET-LM facilitates adipogenesis by stimulating PPARγ-mediated signaling cascades in adipocytes which could be useful for quality meat development in animals.
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Barber E, Sinclair AJ, Cameron-Smith D. Comparative actions of omega-3 fatty acids on in-vitro lipid droplet formation. Prostaglandins Leukot Essent Fatty Acids 2013; 89:359-66. [PMID: 24012207 DOI: 10.1016/j.plefa.2013.07.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2013] [Revised: 07/18/2013] [Accepted: 07/25/2013] [Indexed: 01/24/2023]
Abstract
Storage of fat into lipid droplets (LDs) is the key step in adipogenesis. Previously the omega-3 polyunsaturated fatty acid (n-3PUFA) eicosapentaenoic acid (EPA; C20:5n-3) has been shown to suppress LD formation, yet the actions of other n-3PUFA is unknown. Here, we examined the impact of the three major long chain n-3PUFA; EPA, docosapentaenoic acid (DPA; C22:5n-3) and docosahexaenoic acid (DHA; C22:6n-3) on LD formation in 3T3-L1 adipocytes. Cells were supplemented with 100µM fatty acid during differentiation. All n-3PUFA significantly reduced LD formation and the metabolic disorder marker, SCD1, in comparison to stearic acid (STA; C18:0). This action was more potent for DHA than either EPA or DPA. Furthermore, DHA significantly increased lipolysis and ATGL gene and protein expression but reduced the gene expression of three proteins related to LD formation (Perilipin A, Caveolin-1 and Cidea), compared with other n-3PUFA. Thus, DHA, above EPA and DPA, markedly suppressed fat storage in LDs in in-vitro adipocytes.
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Affiliation(s)
- Elizabeth Barber
- Department of Nutrition and Dietetics, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton 3800, Victoria, Australia.
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Perfluorooctanoate suppresses spheroid attachment on endometrial epithelial cells through peroxisome proliferator-activated receptor alpha and down-regulation of Wnt signaling. Reprod Toxicol 2013; 42:164-71. [PMID: 23978332 DOI: 10.1016/j.reprotox.2013.08.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 07/31/2013] [Accepted: 08/12/2013] [Indexed: 12/28/2022]
Abstract
Exposure of animals to perfluorooctanoic acid (PFOA), a surfactant used in emulsion polymerization processes causes early pregnancy loss, delayed growth and development of fetuses. The mechanisms of action are largely unknown. We studied the effect of PFOA on implantation using an in vitro spheroid-endometrial cell co-culture model. PFOA (10-100μM) significantly reduced Jeg-3 spheroid attachment on RL95-2 endometrial cells. PFOA also suppressed β-catenin expression in Jeg-3 cells. The Wnt agonist Wnt3a stimulated β-catenin expression in Jeg-3 cells and reversed the PFOA suppression of the spheroid attachment. The putative PFOA receptors (PPARα, β, γ) present in both cell lines were not affected by PFOA (0.01-100μM). The PPARα antagonist MK886 restored the β-catenin and E-cadherin expression levels in Jeg-3 cells and reversed the suppression of the spheroid attachment caused by PFOA. Taken together, PFOA suppresses spheroid attachment through PPARα and Wnt signaling pathways via down-regulation of β-catenin and E-cadherin expression.
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Feeding a DHA-enriched diet increases skeletal muscle protein synthesis in growing pigs: association with increased skeletal muscle insulin action and local mRNA expression of insulin-like growth factor 1. Br J Nutr 2013; 110:671-80. [PMID: 23433177 DOI: 10.1017/s0007114512005740] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Dietary n-3 PUFA have been demonstrated to promote muscle growth in growing animals. In the present study, fractional protein synthesis rates (FSR) in the skeletal muscle of growing pigs fed a DHA-enriched (DE) diet (DE treatment) or a soyabean oil (SO) diet (SO treatment) were evaluated in the fed and feed-deprived states. Feeding-induced increases in muscle FSR, as well as the activation of the mammalian target of rapamycin and protein kinase B, were higher in the DE treatment as indicated by the positive interaction between diet and feeding. In the fed state, the activation of eIF4E-binding protein 1 in the skeletal muscle of pigs on the DE diet was higher than that in pigs on the SO diet (P<0·05). Feeding the DE diet increased muscle insulin-like growth factor 1 (IGF-1) expression (P<0·05) and insulin action (as demonstrated by increased insulin receptor (IR) phosphorylation, P<0·05), resulting in increased IR substrate 1 activation in the fed state. However, no difference in plasma IGF-1 concentration or hepatic IGF-1 expression between the two treatments was associated. The increased IGF-1 expression in the DE treatment was associated with increased mRNA expression of the signal transducer and activator of transcription 5A and decreased mRNA expression of protein tyrosine phosphatase, non-receptor type 3 in skeletal muscle. Moreover, mRNA expression of protein tyrosine phosphatase, non-receptor type 1 (PTPN1), the activation of PTPN1 and the activation of NF-κB in muscle were significantly lower in the DE treatment (P<0·05). The results of the present study suggest that feeding a DE diet increased feeding-induced muscle protein synthesis in growing pigs, and muscle IGF-1 expression and insulin action were involved in this action.
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Reardon HT, Hsieh AT, Park WJ, Kothapalli KS, Anthony JC, Nathanielsz PW, Brenna JT. Dietary long-chain polyunsaturated fatty acids upregulate expression of FADS3 transcripts. Prostaglandins Leukot Essent Fatty Acids 2013; 88:15-9. [PMID: 22398025 PMCID: PMC3386357 DOI: 10.1016/j.plefa.2012.02.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Accepted: 02/10/2012] [Indexed: 12/18/2022]
Abstract
The fatty acid desaturase (FADS) gene family at 11q12-13.1 includes FADS1 and FADS2, both known to mediate biosynthesis of omega-3 and omega-6 long-chain polyunsaturated fatty acids (LCPUFA). FADS3 is a putative desaturase due to its sequence similarity with FADS1 and FADS2, but its function is unknown. We have previously described 7 FADS3 alternative transcripts (AT) and 1 FADS2 AT conserved across multiple species. This study examined the effect of dietary LCPUFA levels on liver FADS gene expression in vivo and in vitro, evaluated by qRT-PCR. Fourteen baboon neonates were randomized to three diet groups for their first 12 weeks of life, C: Control, no LCPUFA, L: 0.33% docosahexaenoic acid (DHA)/0.67% arachidonic acid (ARA) (w/w); and L3: 1.00% DHA/0.67% ARA (w/w). Liver FADS1 and both FADS2 transcripts were downregulated by at least 50% in the L3 group compared to controls. In contrast, FADS3 AT were upregulated (L3 > C), with four transcripts significantly upregulated by 40% or more. However, there was no evidence for a shift in liver fatty acids to coincide with increased FADS3 expression. Significant upregulation of FADS3 AT was also observed in human liver-derived HepG2 cells after DHA or ARA treatment. The PPARγ antagonist GW9662 prevented FADS3 upregulation, while downregulation of FADS1 and FADS2 was unaffected. Thus, FADS3 AT were directly upregulated by LCPUFA by a PPARγ-dependent mechanism unrelated to regulation of other desaturases. This opposing pattern and mechanism of regulation suggests a dissimilar function for FADS3 AT compared to other FADS gene products.
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Affiliation(s)
- Holly T. Reardon
- Division of Nutritional Sciences, Cornell University, Ithaca, New York, USA
| | - Andrea T. Hsieh
- Division of Nutritional Sciences, Cornell University, Ithaca, New York, USA
| | - Woo Jung Park
- Division of Nutritional Sciences, Cornell University, Ithaca, New York, USA
| | | | - Joshua C. Anthony
- Mead Johnson Nutrition, 2400 W. Lloyd Expressway, Evansville, Indiana, USA
| | - Peter W. Nathanielsz
- Center for Pregnancy and Newborn Research, University of Texas Health Science Center, San Antonio, Texas, USA
| | - J. Thomas Brenna
- Division of Nutritional Sciences, Cornell University, Ithaca, New York, USA
- Corresponding author: voice (607) 255-9182, fax (607) 255-1033,
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Docosahexaenoic acid suppresses the expression of FoxO and its target genes. J Nutr Biochem 2012; 23:1609-16. [PMID: 22444500 DOI: 10.1016/j.jnutbio.2011.11.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 11/06/2011] [Accepted: 11/08/2011] [Indexed: 12/17/2022]
Abstract
Docosahexaenoic acid (DHA), an n-3 polyunsaturated fatty acid, has previously been shown to ameliorate obesity-associated metabolic syndrome. To decipher the mechanism responsible for the beneficial effects of DHA on energy/glucose homeostasis and the metabolic syndrome, 30 weaned cross-bred pigs were randomly assigned to three groups and fed ad libitum with a standard diet supplemented with 2% of beef tallow, soybean oil or DHA oil for 30 days, and the gene expression profile of various tissues was evaluated by quantitative real-time polymerase chain reaction. The DHA-supplemented diets reduced the expression of forkhead box O transcription factor (FoxO) 1 and FoxO3 in the liver and adipose tissue. DHA treatments also decreased the expression of FoxO1 and FoxO3 in human hepatoma cells, SK-HEP-1 and human and porcine primary adipocytes. In addition, DHA also down-regulated FoxO target genes, such as microsomal triacylglycerol transfer protein (MTP), glucose-6-phosphatase, apolipoprotein C-III (apoC-III) and insulin-like growth factor binding-protein 1 in the liver, as well as reduced total plasma levels of cholesterol and triacylglycerol in the pig. Transcriptional suppression of FoxO1, FoxO3, apoC-III and MTP by DHA was further confirmed by reporter assays with each promoter construct. Taken together, our study indicates that DHA modulates lipid and glucose homeostasis in part by down-regulating FoxO function. The down-regulation of genes associated with triacylglycerol metabolism and very low density lipoprotein assembly is likely to contribute to the beneficial effects of DHA on the metabolic syndrome.
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Eicosapentaenoic and docosahexaenoic acids as inflammation-modulating and lipid homeostasis influencing nutraceuticals: A review. J Funct Foods 2012. [DOI: 10.1016/j.jff.2011.10.008] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
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Abstract
With the diabetes epidemic reaching menacing proportions worldwide, there is an urgent need for the development of cost-efficient prevention strategies to be effective at the population level. Great potential in this direction lies in properly designed, large-scale dietary interventions. The macronutrient composition and the caloric content of our diet are major determinants of glucose homeostasis and there is a continuously growing list of foods, nutrients or individual compounds that have been associated with an increased or reduced incidence of diabetes mellitus. These include fat, carbohydrates, fibre, alcohol, polyphenols and other micronutrients or individual dietary compounds, which have been shown to either promote or prevent a progression towards a (pre-)diabetic state. This review aims to briefly summarize relevant epidemiological data linking foods to diabetes and to provide insights into the mechanisms through which these effects are mediated. These include improvement of insulin sensitivity or promotion of insulin resistance, regulation of inflammatory pathways, regulation of glucose transport and tissue glucose uptake, aggravation or attenuation of postprandial glycaemia/insulinaemia, interactions with hormonal responses and β-cell-dependent mechanisms.
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Affiliation(s)
- Theodoros Thomas
- Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany.
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Pan JP, Zhang HQ, Wei-Wang, Guo YF, Na-Xiao, Cao XH, Liu LJ. Some subtypes of endocannabinoid/endovanilloid receptors mediate docosahexaenoic acid-induced enhanced spatial memory in rats. Brain Res 2011; 1412:18-27. [DOI: 10.1016/j.brainres.2011.07.015] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Revised: 07/04/2011] [Accepted: 07/06/2011] [Indexed: 10/18/2022]
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Jiang M, Strand DW, Franco OE, Clark PE, Hayward SW. PPARγ: a molecular link between systemic metabolic disease and benign prostate hyperplasia. Differentiation 2011; 82:220-36. [PMID: 21645960 DOI: 10.1016/j.diff.2011.05.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Revised: 05/02/2011] [Accepted: 05/04/2011] [Indexed: 11/26/2022]
Abstract
The emergent epidemic of metabolic syndrome and its complex list of sequelae mandate a more thorough understanding of benign prostatic hyperplasia and lower urinary tract symptoms (BPH/LUTS) in the context of systemic metabolic disease. Here we discuss the nature and origins of BPH, examine its role as a component of LUTS and review retrospective clinical studies that have drawn associations between BPH/LUTS and type II diabetes, inflammation and dyslipidemia. PPARγ signaling, which sits at the nexus of systemic metabolic disease and BPH/LUTS through its regulation of inflammation and insulin resistance, is proposed as a candidate for molecular manipulation in regard to BPH/LUTS. Finally, we introduce new cell and animal models that are being used to study the consequences of obesity, diabetes and inflammation on benign prostatic growth.
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Affiliation(s)
- Ming Jiang
- Department of Urologic Surgery, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
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Abstract
Although there are indications for modulatory effects of PUFA on associations between SNP and obesity risk, scientific evidence in human subjects is still scarce. The present analyses investigated interaction effects between SNP in candidate genes for obesity and PUFA in erythrocyte membranes on obesity risk. Within the second Bavarian Food Consumption Survey (cross-sectional, population-based), 568 adults provided blood samples. Fatty acid composition of erythrocyte membranes was analysed by means of GC. Genotyping was performed for twenty-one genes, including cytokines, adipokines, neurotransmitters and transcription factors. In addition, plasma IL-6 concentrations were analysed. For the statistical analysis, a logistic regression model assuming additive genetic effects was chosen. About 20 % of the study participants were classified as obese (BMI ≥ 30 kg/m(2)). Several significant gene-PUFA interactions were found, indicating regulatory effects of PUFA by gene variants of IL-2, IL-6, IL-18, TNF receptor family member 1B and 21, leptin receptor and adiponectin on obesity risk. After stratification by genotype, the strongest effects were found for rs2069779 (IL-2) and all tested PUFA as well as for rs1800795 (IL-6) and linoleic or arachidonic acid. The obesity risk of minor allele carriers significantly decreased with increasing fatty acid content. The genetic PUFA-IL-6 interaction was also reflected in plasma IL-6 concentrations. If replicated in a prospective study with sufficient statistical power, the results would indicate a beneficial effect of high PUFA supply for a substantial proportion of the population with respect to obesity risk.
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The function of porcine PPARγ and dietary fish oil effect on the expression of lipid and glucose metabolism related genes. J Nutr Biochem 2011; 22:179-86. [DOI: 10.1016/j.jnutbio.2010.01.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2009] [Revised: 01/09/2010] [Accepted: 01/14/2010] [Indexed: 12/27/2022]
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IUGR decreases PPARγ and SETD8 Expression in neonatal rat lung and these effects are ameliorated by maternal DHA supplementation. Early Hum Dev 2010; 86:785-91. [PMID: 20869820 PMCID: PMC3138525 DOI: 10.1016/j.earlhumdev.2010.08.026] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2010] [Revised: 08/22/2010] [Accepted: 08/31/2010] [Indexed: 12/28/2022]
Abstract
Intrauterine growth restriction (IUGR) is associated with altered lung development in human and rat. The transcription factor PPARγ, is thought to contribute to lung development. PPARγ is activated by docosahexanoic acid (DHA). One contribution of PPARγ to lung development may be its direct regulation of chromatin modifying enzymes, such as Setd8. In this study, we hypothesized that IUGR would result in a gender-specific reduction in PPARγ, Setd8 and associated H4K20Me levels in the neonatal rat lung. Because DHA activates PPARγ, we also hypothesized that maternal DHA supplementation would normalize PPARγ, Setd8, and H4K20Me levels in the IUGR rat lung. We found that IUGR decreased PPARγ levels, with an associated decrease in Setd8 levels in both male and female rat lungs. Levels of the Setd8-dependent histone modification, H4K20Me, were reduced on the PPARγ gene in both males and females while whole lung H4K20Me was only reduced in male lung. Maternal DHA supplementation ameliorated these effects in offspring. We conclude that IUGR decreases lung PPARγ, Setd8 and PPARγ H4K20Me independent of gender, while decreasing whole lung H4K20Me in males only. These outcomes are offset by maternal DHA. We speculate that maintenance of the epigenetic milieu may be one role of PPARγ in the lung and suggests a novel benefit of maternal DHA supplementation in IUGR.
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Oster RT, Tishinsky JM, Yuan Z, Robinson LE. Docosahexaenoic acid increases cellular adiponectin mRNA and secreted adiponectin protein, as well as PPARγ mRNA, in 3T3-L1 adipocytes. Appl Physiol Nutr Metab 2010; 35:783-9. [DOI: 10.1139/h10-076] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Adiponectin, a protein secreted from adipose tissue, has been shown to have anti-diabetic and anti-inflammatory effects, but its regulation is not completely understood. Long-chain n-3 fatty acids eicosapentaenoic acid (20:5n-3; EPA) and docosahexaenoic acid (22:6n-3; DHA) may be involved in adiponectin regulation as they are potential ligands for peroxisome proliferator-activated receptor-γ (PPARγ), a key transcription factor for the adiponectin gene. To examine this, 3T3-L1 adipocytes were incubated with 125 µmol·L–1 EPA, DHA, palmitic, or oleic acids complexed to albumin, or with albumin alone (control) for 24 h. Adipocytes were also incubated for 24 h with EPA and DHA plus bisphenol-A-diglycidyl ether (BADGE), a PPARγ antagonist. Both EPA and DHA increased (p < 0.05) secreted adiponectin concentration compared with the control (44% and 102%, respectively), but did not affect cellular adiponectin protein content. Incubation with BADGE and DHA inhibited increases in secreted adiponectin protein, suggesting that DHA may act through a PPARγ-dependent mechanism. However, BADGE had no effect on EPA-induced increases in secreted adiponectin protein. Only DHA enhanced (p < 0.05) PPARγ and adiponectin mRNA expression compared wtih the control. Our results demonstrate that DHA increases cellular adiponectin mRNA and secreted adiponectin protein in 3T3-L1 adipocytes, possibly by a mechanism involving PPARγ. Moreover, DHA increased adiponectin concentration to a greater extent (40% more, p < 0.05) compared with EPA, emphasizing the need to consider the independent actions of EPA and DHA in adipocytes.
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Affiliation(s)
- Richard T. Oster
- Department of Human Health and Nutritional Sciences, Animal Science and Nutrition Building, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Justine M. Tishinsky
- Department of Human Health and Nutritional Sciences, Animal Science and Nutrition Building, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Zongfei Yuan
- Department of Human Health and Nutritional Sciences, Animal Science and Nutrition Building, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Lindsay E. Robinson
- Department of Human Health and Nutritional Sciences, Animal Science and Nutrition Building, University of Guelph, Guelph, ON N1G 2W1, Canada
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Tseng YW, Wang PH, Lee HS, Liu BH, Mersmann HJ, Lin EC, Ding ST. Regulation of the expression of angiotensin-converting enzyme 2 by polyunsaturated fatty acids in porcine adipocytes1. J Anim Sci 2010; 88:3563-7. [DOI: 10.2527/jas.2010-2905] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Yang CC, Deng SJ, Hsu CC, Liu BH, Lin EC, Cheng WTK, Wang PH, Ding ST. Visfatin regulates genes related to lipid metabolism in porcine adipocytes. J Anim Sci 2010; 88:3233-41. [PMID: 20562354 DOI: 10.2527/jas.2010-2799] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Visfatin is a visceral adipose tissue-specific adipocytokine that plays a positive role in attenuating insulin resistance by binding to the insulin receptor. Visfatin has been suggested to play a role in the regulation of lipid metabolism and inflammation; however, the mechanism remains unclear. We investigated the effects of visfatin on the regulation of gene expression in cultured porcine preadipocytes and differentiated adipocytes. In preadipocytes, the mRNA abundance of lipoprotein lipase and PPARgamma were significantly increased by visfatin or insulin treatment after 8 d (all P < 0.05). In the presence of insulin, the mRNA abundance of adipocyte fatty acid-binding protein was 24.7-fold greater than in the untreated group (P < 0.05), whereas visfatin alone had no effect on adipocyte fatty acid-binding protein mRNA abundance. Adipocyte differentiation was induced by insulin treatment for 8 d. In differentiated porcine adipocytes, exposure to insulin or visfatin for 24 h increased (P < 0.05) fatty acid synthase mRNA abundance but had no effect on the expression of sterol regulatory element binding-protein 1c mRNA. We also found a 5.8-fold upregulation of IL-6 expression in porcine adipocytes after 24 h of treatment with visfatin (P < 0.05). These results demonstrated that visfatin upregulated lipoprotein lipase expression in preadipocytes, potentially facilitating lipid uptake, and increased the gene expression of fatty acid synthase in differentiated adipocytes to potentially enhance lipogenic activity. Furthermore, visfatin can upregulate IL-6 expression in differentiated porcine adipocytes. The information presented in this study provides insights into the roles of visfatin in lipid metabolism in pigs.
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Affiliation(s)
- C C Yang
- Department of Animal Science and Technology, National Taiwan University, Taipei, Taiwan, ROC
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Yu YH, Wang PH, Cheng WTK, Mersmann HJ, Wu SC, Ding ST. Porcine peroxisome proliferator-activated receptor delta mediates the lipolytic effects of dietary fish oil to reduce body fat deposition. J Anim Sci 2010; 88:2009-18. [PMID: 20190170 DOI: 10.2527/jas.2009-2597] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Peroxisome proliferator-activated receptor delta promotes fatty acid catabolism and energy expenditure in skeletal muscle and adipose tissues. A ligand for PPARdelta is required to activate PPARdelta function. Polyunsaturated fatty acids are potential ligands for PPARdelta activation. The current experiment was designed to determine the potential for PUFA, particularly from dietary fish oil, to activate porcine PPARdelta in vivo. Transgenic mice were generated to overexpress porcine PPARdelta in the adipose tissue. Mice were fed a high-saturated fat (13% beef tallow), or high-unsaturated fat (13% fish oil) diet, or a diet containing 4 mg/kg of a PPARdelta ligand (L165041) for 4 mo. Compared with beef tallow feeding, fish oil feeding reduced fat mass and decreased (P < 0.05) plasma triacylglycerol and FFA concentrations in the transgenic mice. Adipose tissue expression of genes involved in adipogenesis (i.e., lipoprotein lipase and adipocyte fatty acid-binding protein) was decreased in transgenic mice fed fish oil or the PPARdelta ligand. In the same mice, expression of the lipolytic gene, hormone-sensitive lipase was increased (P < 0.05). Fish oil feeding also stimulated expression of genes participating in fatty acid oxidation in the liver of transgenic mice compared with wild-type mice. Overall, these results indicate that PUFA may serve as natural and effective regulators of lipid catabolism in vivo and many of these effects may be generated from activation of PPARdelta.
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Affiliation(s)
- Y H Yu
- Department of Animal Science and Technology/Institute of Biotechnology, National Taiwan University, Taipei 106, Taiwan
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