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Shahoei SH, Nelson ER. Nuclear receptors, cholesterol homeostasis and the immune system. J Steroid Biochem Mol Biol 2019; 191:105364. [PMID: 31002862 PMCID: PMC6589364 DOI: 10.1016/j.jsbmb.2019.04.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/09/2019] [Accepted: 04/10/2019] [Indexed: 12/30/2022]
Abstract
Cholesterol is essential for maintaining membrane fluidity in eukaryotes. Additionally, the synthetic cascade of cholesterol results in precursor molecules important for cellular function such as lipid raft formation and protein prenylation. As such, cholesterol homeostasis is tightly regulated. Interestingly, it is now known that some cholesterol precursors and many metabolites serve as active signaling molecules, binding to different classes of receptors including the nuclear receptors. Furthermore, many cholesterol metabolites or their nuclear receptors have been implicated in the regulation of the immune system in normal physiology and disease. Therefore, in this focused review, cholesterol homeostasis and nuclear receptors involved in this regulation will be discussed, with particular emphasis on how these cascades influence the immune system.
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Affiliation(s)
- Sayyed Hamed Shahoei
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana Champaign, Urbana, IL, United States
| | - Erik R Nelson
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana Champaign, Urbana, IL, United States; Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, United States; Cancer Center at Illinois, University of Illinois at Urbana-Champaign, Urbana, IL, United States; University of Illinois Cancer Center, University of Illinois at Chicago, Chicago, IL, United States; Carl R. Woese Institute for Genomic Biology, Anticancer Discovery from Pets to People Theme, University of Illinois at Urbana Champaign, Urbana, IL, United States.
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Vega-Badillo J. ALTERACIONES EN LA HOMEOSTASIS DEL COLESTEROL HEPÁTICO Y SUS IMPLICACIONES EN LA ESTEATOHEPATITIS NO ALCOHÓLICA. TIP REVISTA ESPECIALIZADA EN CIENCIAS QUÍMICO-BIOLÓGICAS 2017. [DOI: 10.1016/j.recqb.2016.11.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
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Maisonet M, Näyhä S, Lawlor DA, Marcus M. Prenatal exposures to perfluoroalkyl acids and serum lipids at ages 7 and 15 in females. ENVIRONMENT INTERNATIONAL 2015; 82:49-60. [PMID: 26010307 DOI: 10.1016/j.envint.2015.05.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 04/27/2015] [Accepted: 05/08/2015] [Indexed: 05/18/2023]
Abstract
BACKGROUND In some cross-sectional epidemiologic studies the shape of the association between serum concentrations of perfluoroalkyl acids (PFAAs) and lipids suggests departures from linearity. OBJECTIVES We used statistical approaches allowing for non-linearity to determine associations of prenatal exposures of perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) with lipid concentrations. METHODS PFAAs were measured in serum from pregnant women collected in 1991-1992 at enrollment in the Avon Longitudinal Study of Parents and Children and lipids in serum from their daughters at ages 7 (n=111) and 15 (n=88). The associations of PFAAs with lipids were first explored by cubic splines, followed by piecewise linear regressions by tertiles to obtain regression coefficients (β) and their 95% confidence limits (95% CL) (in mg/dL per 1ng/mL). RESULTS At age 7, total cholesterol was positively associated with prenatal PFOA concentrations in the lower tertile (β=15.01; 95% CL=2.34, 27.69) but not with PFOA concentrations in the middle (β=-3.63; 95% CL=-17.43, 10.16) and upper (β=-1.58; 95% CL=-4.58, 1.42) tertiles. At age 15, a similar pattern was noted as well. Positive associations between LDL-C and prenatal PFOA concentration in the lower tertile were observed in daughters at ages 7 (β=14.91; 95% CL=3.53, 28.12) and 15 (β=13.93; 95% CL=0.60, 27.26). LDL-C was not associated with PFOA concentrations in the middle or upper tertile at any age. Neither HDL-C nor triglycerides was associated with prenatal PFOA exposure. Non-linear patterns of association of total cholesterol and LDL-C with prenatal PFOS were less consistently noted. CONCLUSION Exposure to low levels of PFOA during prenatal development may alter lipid metabolism later in life. Given the small sample size further replication of the association in large independent cohorts is important.
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Affiliation(s)
- Mildred Maisonet
- Department of Epidemiology and Biostatistics, College of Public Health, East Tennessee State University, Johnson City, TN, United States; Center for Environmental and Respiratory Health Research, Faculty of Medicine, University of Oulu, Oulu, Finland.
| | - Simo Näyhä
- Center for Environmental and Respiratory Health Research, Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Debbie A Lawlor
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK; School of Social and Community Medicine, University of Bristol, Bristol, UK
| | - Michele Marcus
- Epidemiology Department, Rollins School of Public Health, Emory University, Atlanta, GA, United States
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Dai Y, Su W, Ding Z, Wang X, Mercanti F, Chen M, Raina S, Mehta JL. Regulation of MSR-1 and CD36 in macrophages by LOX-1 mediated through PPAR-γ. Biochem Biophys Res Commun 2013; 431:496-500. [DOI: 10.1016/j.bbrc.2013.01.029] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Accepted: 01/09/2013] [Indexed: 12/20/2022]
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Jha HC, Srivastava P, Vardhan H, Singh LC, Bhengraj AR, Prasad J, Mittal A. Chlamydia pneumoniae heat shock protein 60 is associated with apoptotic signaling pathway in human atheromatous plaques of coronary artery disease patients. J Cardiol 2011; 58:216-25. [PMID: 21889313 DOI: 10.1016/j.jjcc.2011.07.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2011] [Revised: 07/22/2011] [Accepted: 07/23/2011] [Indexed: 12/11/2022]
Abstract
BACKGROUND Chlamydia pneumoniae heat shock protein (HSP) 60 is known to contribute to the activation of inflammation. In addition, there are contradictory reports on C. pneumoniae and their role in activation of pathways (apoptotic/antiapoptotic/necrosis) in coronary artery disease (CAD). Hence, more studies are required to know the actual role of C. pneumoniae in activation of apoptotic/antiapoptotic/necrosis pathways. METHODS AND RESULTS In this study, two sets of patient groups (cHSP60 positive and cHSP60 negative) were included and gene expression was studied by cDNA micro array and real time polymerase chain reaction arrays. Expression of Caspase-3, 8, 9, c-FLIP, PPAR-γ, PGC-1α, and Gsk-3b were also evaluated at protein level by immunoblotting. In cHSP60 positive CAD patients significantly higher (p<0.001) mRNA expression was found for CCL4, CXCL4, CXCL9, IL-8, CD40LG, CD8, TGFβ1, TGFβ2, APOE, EGR1, CTGF, APOB, LDLR, LPA, and LPL, whereas significantly lower (p<0.001) mRNA expression was detected for CD4, IL1F10, IFNA2, and IL-10 as compared to cHSP60 negative CAD patients. Additionally, at protein level expression of Caspase-3 (p=0.027), 8 (p=0.028), and 9 (p=0.037) were higher and c-FLIP (p=0.028) and PPAR-γ (p=0.95) expression were comparable in cHSP60 positive CAD patients compared to cHSP60 negative CAD patients. CONCLUSION Genes/proteins of pre-apoptotic caspase dependent/independent pathways, chemokines, and inflammatory cytokines receptors were significantly up-regulated in human atheromatous plaques of cHSP60 positive CAD patients suggesting an association of cHSP60 with CAD.
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Affiliation(s)
- Hem Chandra Jha
- Institute of Pathology (ICMR), Safdarjung Hospital Campus, Post Box No. 4909, New Delhi 110 029, India
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Yokozawa T, Kim HJ, Cho EJ. Gravinol ameliorates high-fructose-induced metabolic syndrome through regulation of lipid metabolism and proinflammatory state in rats. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2008; 56:5026-5032. [PMID: 18540612 DOI: 10.1021/jf800213f] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Using a rat model with fructose-induced metabolic syndrome, the effect of gravinol was investigated. Male Wistar rats were fed a 65% fructose diet and administered 10 or 20 mg of gravinol/kg of body weight/day for 2 weeks. High-level fructose feeding led to hyperglycemia, hyperlipidemia, hypertri-glyceridemia, and hypertension. On the other hand, the administration of gravinol significantly lowered serum glucose and total cholesterol levels. The tail arterial blood pressure was significantly elevated with the high-fructose diet. However, rats given gravinol showed a lower blood pressure as compared with fructose-fed control rats. In addition, the triglyceride (TG) levels in serum and lipoprotein fraction were dose-dependently reduced in rats fed gravinol. The decreases of hepatic TG and total cholesterol by gravinol were responsible for the down-regulation of hepatic sterol regulatory element binding protein (SREBP)-1. However, gravinol did not affect the protein levels of hepatic peroxisome proliferator-activated receptor-alpha and SREBP-2. Moreover, gravinol administration in the fructose-fed rats markedly reduced the glycosylated protein and thiobarbituric acid-reactive substance levels in the serum and hepatic mitochondria, and it inhibited the increase of the cyclooxygenase-2 protein level as a result of the down-regulation of nuclear factor kappa B (NF-kappaB). Furthermore, the decrease of anti-apoptotic bcl-2 protein levels and the increase of pro-apoptotic bax protein levels by the high-fructose diet were reversed by gravinol. These findings suggest that fructose-induced metabolic syndrome is attenuated by gravinol administration, which is associated with the reduction of serum lipids and protection against the proinflammatory state induced by oxidative stress.
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Affiliation(s)
- Takako Yokozawa
- Institute of Natural Medicine, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
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Yokozawa T, Kim HY, Kim HJ, Okubo T, Chu DC, Juneja LR. Amla (Emblica officinalisGaertn.) prevents dyslipidaemia and oxidative stress in the ageing process. Br J Nutr 2007; 97:1187-95. [PMID: 17506915 DOI: 10.1017/s0007114507691971] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Amla (Emblica officinalisGaertn.) is widely used in Indian medicine for the treatment of various diseases. We have investigated the effects of amla on the lipid metabolism and protein expression involved in oxidative stress during the ageing process. SunAmla or ethyl acetate extract of amla, a polyphenol-rich fraction, was administered at a dose of 40 or 10 mg/kg body weight per d for 100 d to young rats aged 2 months and aged rats aged 10 months. The lipid levels, such as cholesterol and TAG, in serum and liver were markedly elevated in aged control rats, while they were significantly decreased by the administration of amla. The PPARα is known to regulate the transcription of genes involved in lipid and cholesterol metabolism. The PPARα protein level in liver was reduced in aged control rats. However, the oral administration of amla significantly increased the hepatic PPARα protein level. In addition, oral administration of amla significantly inhibited the serum and hepatic mitochondrial thiobarbituric acid-reactive substance levels in aged rats. Moreover, the elevated expression level of bax was significantly decreased after the oral administration of amla, while the level of bcl-2 led to a significant increase. Furthermore, the expressions of hepatic NF-κB, inducible NO synthase (iNOS), and cyclo-oxygenase-2 (COX-2) protein levels were also increased with ageing. However, amla extract reduced the iNOS and COX-2 expression levels by inhibiting NF-κB activation in aged rats. These results indicate that amla may prevent age-related hyperlipidaemia through attenuating oxidative stress in the ageing process.
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Affiliation(s)
- Takako Yokozawa
- Institute of Natural Medicine, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
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Berger A, Roberts MA, Hoff B. How dietary arachidonic- and docosahexaenoic- acid rich oils differentially affect the murine hepatic transcriptome. Lipids Health Dis 2006; 5:10. [PMID: 16623957 PMCID: PMC1479345 DOI: 10.1186/1476-511x-5-10] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2006] [Accepted: 04/20/2006] [Indexed: 01/26/2023] Open
Abstract
Introduction Herein, we expand our previous work on the effects of long chain polyunsaturated fatty acids (LC-PUFA) on the murine hepatic transcriptome using novel statistical and bioinformatic approaches for evaluating microarray data. The analyses focuses on key differences in the transcriptomic response that will influence metabolism following consumption of FUNG (rich in 20:4n6), FISH (rich in 20:5n3, 22:5n3, and 22:6n3) and COMB, the combination of the two. Results Using a variance-stabilized F-statistic, 371 probe sets (out of 13 K probe sets in the Affymetrix Mu11K chip set) were changed by dietary treatment (P < 0.001). Relative to other groups, COMB had unique affects on murine hepatic transcripts involved in cytoskeletal and carbohydrate metabolism; whereas FUNG affected amino acid metabolism via CTNB1 signaling. All three diets affected transcripts linked to apoptosis and cell proliferation, with evidence FISH may have increased apoptosis and decreased cell proliferation via various transcription factors, kinases, and phosphatases. The three diets affected lipid transport, lipoprotein metabolism, and bile acid metabolism through diverse pathways. Relative to other groups, FISH activated cyps that form hydroxylated fatty acids known to affect vascular tone and ion channel activity. FA synthesis and delta 9 desaturation were down regulated by COMB relative to other groups, implying that a FA mixture of 20:4n6, 20:5n3, and 22:6n3 is most effective at down regulating synthesis, via INS1, SREBP, PPAR alpha, and TNF signaling. Heme synthesis and the utilization of heme for hemoglobin production were likely affected by FUNG and FISH. Finally, relative to other groups, FISH increased numerous transcripts linked to combating oxidative such as peroxidases, an aldehyde dehydrogenase, and heat shock proteins, consistent with the major LC-PUFA in FISH (20:5n3, 22:5n3, 22:6n3) being more oxidizable than the major fatty acids in FUNG (20:4n6). Conclusion Distinct transcriptomic, signaling cascades, and predicted affects on murine liver metabolism have been elucidated for 20:4n6-rich dietary oils, 22:6n3-rich oils, and a surprisingly distinct set of genes were affected by the combination of the two. Our results emphasize that the balance of dietary n6 and n3 LC-PUFA provided for infants and in nutritional and neutraceutical applications could have profoundly different affects on metabolism and cell signaling, beyond that previously recognized.
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Affiliation(s)
- Alvin Berger
- Department of Nutrition, University of North Carolina, Chapel Hill, NC 27599, USA
- Head of Biochemistry, Metabolon, Inc., 800 Capitola Drive, Suite 1, Durham, NC 27713, USA
| | - Matthew A Roberts
- Director, Nestle Corporate Venture Funds, Acquisitions & Business Development, Nestle S.A., 55 Avenue Nestle, 1800 Vevey, Switzerland
| | - Bruce Hoff
- Director of Analytical Sciences, BioDiscovery, Inc., 100 North Sepulveda Blvd., Suite 1230, El Segundo, CA 90245, USA
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Chen Y, Jimenez AR, Medh JD. Identification and regulation of novel PPAR-gamma splice variants in human THP-1 macrophages. ACTA ACUST UNITED AC 2006; 1759:32-43. [PMID: 16542739 PMCID: PMC2765245 DOI: 10.1016/j.bbaexp.2006.01.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2005] [Revised: 12/13/2005] [Accepted: 01/12/2006] [Indexed: 01/01/2023]
Abstract
We have previously identified four novel isoforms of PPAR-gamma transcripts in monkey macrophages (J. Zhou, K.M. Wilson, J.D. Medh, Genetic analysis of four novel peroxisome proliferator receptor-gamma splice variants in monkey macrophages. Biochem. Biophys. Res. Commun., 293 (2002) 274-283). The purpose of this study was to ascertain that these isoforms are also present in humans. Specific primers were designed to amplify individual isoform transcripts. The presence of PPAR-gamma4, PPAR-gamma5, and PPAR-gamma7 transcripts in human THP-1 macrophages was confirmed by RT-PCR and sequencing. A transcript corresponding to PPAR-gamma6 was not detected. The presence of novel full-length transcripts and protein was also ascertained by Northern and Western blot analysis. Treatment of THP-1 cells with 15-deoxy-Delta12,14-prostaglandin J2 (15d-PGJ2) resulted in more than 20% induction in the expression of PPAR-gamma5 and PPAR-gamma7 transcripts by both Northern blot analysis and RT-PCR. Another PPAR-gamma ligand, troglitazone, induced expression of only PPAR-gamma5. Both ligands inhibited the expression of PPAR-gamma1 and PPAR-gamma2. Additionally, 15d-PGJ2 and troglitazone increased the level of apolipoprotein E transcript by 60% but decreased lipoprotein lipase expression by 15% in THP-1 cells. The differential regulation of PPAR-gamma transcripts suggests that each transcript isoform may contribute to macrophage function.
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Affiliation(s)
| | | | - Jheem D. Medh
- Corresponding author. Tel.: +1 818 677 7737; fax: +1 818 677 4068. (J.D. Medh)
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Ram VJ. Therapeutic role of peroxisome proliferator-activated receptors in obesity, diabetes and inflammation. PROGRESS IN DRUG RESEARCH. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRES DES RECHERCHES PHARMACEUTIQUES 2003; 60:93-132. [PMID: 12790340 DOI: 10.1007/978-3-0348-8012-1_3] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear receptor family and play a significant role in regulation of lipid metabolism, hepatic peroxisomal enzyme expression, insulin sensitivity and glucose homeostasis. PPARs have been classified into three subtypes encoded by different genes: PPARalpha (NR1C1), PPARdelta (NR1C2), and PPARgamma (NR1C3). Each subtype of PPARs appears to be differently expressed in a tissue-specific manner because of their binding to specific consensus DNA sequences, known as PPREs (peroxisome proliferator response elements). Thus, PPARs have emerged as potential molecular targets for the design and synthesis of a different class of compounds, considering the conformation of receptors for the treatment of human metabolic disorders. This review covers the rapid progress made in functional analysis of PPARs and progress made towards the identification of ligands for each subtype receptor.
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Affiliation(s)
- Vishnu Ji Ram
- Medicinal Chemistry Division, Central Drug Research Institute, Lucknow 226001, India.
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Mezei O, Banz WJ, Steger RW, Peluso MR, Winters TA, Shay N. Soy isoflavones exert antidiabetic and hypolipidemic effects through the PPAR pathways in obese Zucker rats and murine RAW 264.7 cells. J Nutr 2003; 133:1238-43. [PMID: 12730403 DOI: 10.1093/jn/133.5.1238] [Citation(s) in RCA: 262] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The hypocholesterolemic and anti-atherosclerotic mechanism by which soy may exert a beneficial effect remains unclear. Peroxisome-proliferator activated receptors (PPAR) are promiscuous nuclear receptors that regulate the transcription of genes involved in lipid and glucose homeostasis and lipid metabolism within the cell. We hypothesize that the isoflavones improve lipid and glucose metabolism by acting as an antidiabetic PPAR agonist. Male and female obese Zucker rats (OZR) were used as a model of Type 2 diabetes, and OZR fed a high isoflavone soy protein diet displayed improvements in lipid metabolism consistent with results in humans treated with antidiabetic PPAR agonists such as the fibrates or glitazones. Liver triglyceride and cholesterol concentrations were lower in all OZR fed high-isoflavone soy protein diets than in rats fed low-isoflavone and casein diets (P < 0.05). Concurrently, PPAR-directed gene expression was evaluated in a cell culture model. An isoflavone-containing soy extract doubled PPAR-directed gene expression (P < 0.05) in RAW 264.7 cells containing either a PPARalpha or PPARgamma expression plasmid. A similar induction was observed when the soy isoflavones genistein or daidzein were used to treat cells. Both isoflavones doubled PPARalpha-directed gene expression (P < 0.05), whereas they increased PPARgamma-directed gene expression 200-400% (P < 0.05). This study suggests that soy isoflavones improve lipid metabolism, produce an antidiabetic effect, and activate PPAR receptors.
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Affiliation(s)
- Orsolya Mezei
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
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Berger A, Mutch DM, Bruce German J, Roberts MA. Dietary effects of arachidonate-rich fungal oil and fish oil on murine hepatic and hippocampal gene expression. Lipids Health Dis 2002; 1:2. [PMID: 12617750 PMCID: PMC139963 DOI: 10.1186/1476-511x-1-2] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2002] [Accepted: 10/21/2002] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The functions, actions, and regulation of tissue metabolism affected by the consumption of long chain polyunsaturated fatty acids (LC-PUFA) from fish oil and other sources remain poorly understood; particularly how LC-PUFAs affect transcription of genes involved in regulating metabolism. In the present work, mice were fed diets containing fish oil rich in eicosapentaenoic acid and docosahexaenoic acid, fungal oil rich in arachidonic acid, or the combination of both. Liver and hippocampus tissue were then analyzed through a combined gene expression- and lipid- profiling strategy in order to annotate the molecular functions and targets of dietary LC-PUFA. RESULTS Using microarray technology, 329 and 356 dietary regulated transcripts were identified in the liver and hippocampus, respectively. All genes selected as differentially expressed were grouped by expression patterns through a combined k-means/hierarchical clustering approach, and annotated using gene ontology classifications. In the liver, groups of genes were linked to the transcription factors PPARalpha, HNFalpha, and SREBP-1; transcription factors known to control lipid metabolism. The pattern of differentially regulated genes, further supported with quantitative lipid profiling, suggested that the experimental diets increased hepatic beta-oxidation and gluconeogenesis while decreasing fatty acid synthesis. Lastly, novel hippocampal gene changes were identified. CONCLUSIONS Examining the broad transcriptional effects of LC-PUFAs confirmed previously identified PUFA-mediated gene expression changes and identified novel gene targets. Gene expression profiling displayed a complex and diverse gene pattern underlying the biological response to dietary LC-PUFAs. The results of the studied dietary changes highlighted broad-spectrum effects on the major eukaryotic lipid metabolism transcription factors. Further focused studies, stemming from such transcriptomic data, will need to dissect the transcription factor signaling pathways to fully explain how fish oils and arachidonic acid achieve their specific effects on health.
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Affiliation(s)
- Alvin Berger
- Metabolic and Genomic Regulation, Nestlé Research Center, Vers-chez-les-Blanc, CH-1000 Lausanne 26, Switzerland
- Current Address: Cytochroma, Inc., Manager Lipidomics™, 330 Cochrane Drive, Markham, Ontario, Canada
| | - David M Mutch
- Metabolic and Genomic Regulation, Nestlé Research Center, Vers-chez-les-Blanc, CH-1000 Lausanne 26, Switzerland
- Institut de Biologie Animale, Université de Lausanne, CH-1015 Lausanne, Switzerland
| | - J Bruce German
- External Scientific Network, Nestlé Research Center, Vers-chez-les-Blanc, CH-1000 Lausanne 26, Switzerland
- Department of Food Science, University of California, Davis, CA 95616, USA
| | - Matthew A Roberts
- Metabolic and Genomic Regulation, Nestlé Research Center, Vers-chez-les-Blanc, CH-1000 Lausanne 26, Switzerland
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