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A 90-day repeated-dose toxicity study of dietary alpha linolenic acid-enriched diacylglycerol oil in rats. Regul Toxicol Pharmacol 2018; 97:33-47. [DOI: 10.1016/j.yrtph.2018.05.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 05/29/2018] [Accepted: 05/30/2018] [Indexed: 11/24/2022]
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2
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Effect of α-linolenic acid-rich diacylglycerol oil on protein kinase C activation in the rat digestive tract and lingual mucosa. Food Chem Toxicol 2017; 103:168-173. [DOI: 10.1016/j.fct.2017.02.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 12/27/2016] [Accepted: 02/23/2017] [Indexed: 11/21/2022]
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Honda H, Fujita Y, Hayashi A, Ikeda N, Ito Y, Morita O. Genotoxicity evaluation of alpha-linolenic acid-diacylglycerol oil. Toxicol Rep 2016; 3:716-722. [PMID: 28959597 PMCID: PMC5616014 DOI: 10.1016/j.toxrep.2016.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 08/08/2016] [Accepted: 08/08/2016] [Indexed: 11/07/2022] Open
Abstract
We evaluated the genotoxicity of ALA-DAG oil using standard tests. Bacterial reverse mutation and in vitro/in vivo micronucleus tests were conducted. No genotoxicity was observed under the testing conditions.
The alpha-linolenic acid (ALA)-diacylglycerol (DAG) oil is an edible oil enriched with DAG (>80%) and ALA (>50%). Although DAG oil, which mainly consists of oleic and linoleic acids has no genotoxic concerns, the fatty acid composition could affect the chemical property of DAG. Therefore, the purpose of this study was to evaluate the genotoxicity of ALA-DAG oil using standard genotoxicity tests in accordance with the OECD guidelines. ALA-DAG oil showed negative results in the bacterial reverse mutation test (Ames test) and in vitro micronucleus test in cultured Chinese hamster lung cells with and without metabolic activation, and in the in vivo bone marrow micronucleus test in mice. Our results did not show any genotoxicity, suggesting that the fatty acid composition had no deleterious effects. We conclude that ALA-DAG oil had no genotoxicity concerns under the testing conditions.
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Key Words
- 2AA, 2-aminoanthracene
- 9AA, 9-aminoacridine hydrochloride hydrate
- AF-2, 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide
- ALA, alpha-linolenic acid
- Alpha-linolenic acid
- Alpha-linolenic acid-rich diacylglycerol
- B(a)P, benzo(a)pyrene
- CLC, Colchicine
- CP, cyclophosphamide
- DAG, diacylglycerol
- DMSO, dimethyl sulfoxide
- Diacylglycerol
- Fatty acid composition
- Genotoxicity
- ICH, International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use
- LA, linolenic acid
- MMC, mitomycin C
- MNPCE, micronucleated polychromatic erythrocyte
- NCE, normochromatic erythrocyte
- NaN3, sodium azide
- TAG, triacylglycerol
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Affiliation(s)
- Hiroshi Honda
- R&D Safety Science Research, Kao Corporation, 2606 Akabane, Ichikai-Machi, Haga-Gun, Tochigi 321-3497, Japan
| | - Yurika Fujita
- R&D Safety Science Research, Kao Corporation, 2606 Akabane, Ichikai-Machi, Haga-Gun, Tochigi 321-3497, Japan
| | - Aya Hayashi
- Drug Safety Research Laboratories, Shin Nippon Biomedical Laboratories Ltd., 2438 Miyanoura, Yoshida, Kagoshima 891-1394, Japan
| | - Naohiro Ikeda
- R&D Safety Science Research, Kao Corporation, 2606 Akabane, Ichikai-Machi, Haga-Gun, Tochigi 321-3497, Japan
| | - Yuichi Ito
- R&D Safety Science Research, Kao Corporation, 2606 Akabane, Ichikai-Machi, Haga-Gun, Tochigi 321-3497, Japan
| | - Osamu Morita
- R&D Safety Science Research, Kao Corporation, 2606 Akabane, Ichikai-Machi, Haga-Gun, Tochigi 321-3497, Japan
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Demizieux L, Piscitelli F, Troy-Fioramonti S, Iannotti FA, Borrino S, Gresti J, Muller T, Bellenger J, Silvestri C, Di Marzo V, Degrace P. Early Low-Fat Diet Enriched With Linolenic Acid Reduces Liver Endocannabinoid Tone and Improves Late Glycemic Control After a High-Fat Diet Challenge in Mice. Diabetes 2016; 65:1824-37. [PMID: 27207550 DOI: 10.2337/db15-1279] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 03/28/2016] [Indexed: 11/13/2022]
Abstract
Evidence suggests that alterations of glucose and lipid homeostasis induced by obesity are associated with the elevation of endocannabinoid tone. The biosynthesis of the two main endocannabinoids, N-arachidonoylethanolamine and 2-arachidonoyl-glycerol, which derive from arachidonic acid, is influenced by dietary fatty acids (FAs). We investigated whether exposure to n-3 FA at a young age may decrease tissue endocannabinoid levels and prevent metabolic disorders induced by a later high-fat diet (HFD) challenge. Three-week-old mice received a 5% lipid diet containing lard, lard plus safflower oil, or lard plus linseed oil for 10 weeks. Then, mice were challenged with a 30% lard diet for 10 additional weeks. A low n-6/n-3 FA ratio in the early diet induces a marked decrease in liver endocannabinoid levels. A similar reduction was observed in transgenic Fat-1 mice, which exhibit high tissue levels of n-3 FA compared with wild-type mice. Hepatic expression of key enzymes involved in carbohydrate and lipid metabolism was concomitantly changed. Interestingly, some gene modifications persisted after HFD challenge and were associated with improved glycemic control. These findings indicate that early dietary interventions based on n-3 FA may represent an alternative strategy to drugs for reducing endocannabinoid tone and improving metabolic parameters in the metabolic syndrome.
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Affiliation(s)
- Laurent Demizieux
- Team Pathophysiology of Dyslipidemia, Faculty of Sciences Gabriel, INSERM UMR866 "Lipides, Nutrition, Cancer," Université de Bourgogne Franche-Comté, Dijon, France
| | - Fabiana Piscitelli
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Pozzuoli, Naples, Italy
| | - Stephanie Troy-Fioramonti
- Team Pathophysiology of Dyslipidemia, Faculty of Sciences Gabriel, INSERM UMR866 "Lipides, Nutrition, Cancer," Université de Bourgogne Franche-Comté, Dijon, France
| | - Fabio Arturo Iannotti
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Pozzuoli, Naples, Italy
| | - Simona Borrino
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Pozzuoli, Naples, Italy
| | - Joseph Gresti
- Team Pathophysiology of Dyslipidemia, Faculty of Sciences Gabriel, INSERM UMR866 "Lipides, Nutrition, Cancer," Université de Bourgogne Franche-Comté, Dijon, France
| | - Tania Muller
- Team Pathophysiology of Dyslipidemia, Faculty of Sciences Gabriel, INSERM UMR866 "Lipides, Nutrition, Cancer," Université de Bourgogne Franche-Comté, Dijon, France
| | - Jerome Bellenger
- Team Lipid Transfer Proteins and Lipoprotein Metabolism, Faculty of Sciences Gabriel, INSERM UMR866 "Lipides, Nutrition, Cancer," Université de Bourgogne Franche-Comté, Dijon, France
| | - Cristoforo Silvestri
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Pozzuoli, Naples, Italy
| | - Vincenzo Di Marzo
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Pozzuoli, Naples, Italy
| | - Pascal Degrace
- Team Pathophysiology of Dyslipidemia, Faculty of Sciences Gabriel, INSERM UMR866 "Lipides, Nutrition, Cancer," Université de Bourgogne Franche-Comté, Dijon, France
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5
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Balogun KA, Randunu RS, Cheema SK. The effect of dietary omega-3 polyunsaturated fatty acids on plasma lipids and lipoproteins of C57BL/6 mice is age and sex specific. Prostaglandins Leukot Essent Fatty Acids 2014; 91:39-47. [PMID: 24935799 DOI: 10.1016/j.plefa.2014.05.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 05/15/2014] [Accepted: 05/20/2014] [Indexed: 12/31/2022]
Abstract
There is clear evidence of the effects of sex and age on the prevalence of cardiovascular disease. We investigated the interactions of dietary omega (n)-3 polyunsaturated fatty acids (PUFA), sex, and age on plasma lipids and lipoproteins in the offspring of C57BL/6 mice exposed to high, medium, or low n-3 PUFA at weaning and 16 weeks postweaning. There was an increase in plasma triglycerides from weaning to 16 weeks in male and female offspring; however, the high n-3 PUFA group showed a reduction in triglycerides in both sexes at 16 weeks. High n-3 PUFA caused an increase in plasma LDL-cholesterol from weaning to 16 weeks in male offspring; however, the LDL particle size was significantly larger in the high n-3 PUFA group. Plasma from male mice showed higher cholesterol efflux compared to females; high n-3 PUFA increased cholesterol efflux. Thus the effects of n-3 PUFA are age and sex dependent.
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Affiliation(s)
- K A Balogun
- Department of Biochemistry, Memorial University, St. John׳s, NL, Canada
| | - R S Randunu
- Department of Biochemistry, Memorial University, St. John׳s, NL, Canada
| | - S K Cheema
- Department of Biochemistry, Memorial University, St. John׳s, NL, Canada.
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Jourdan T, Demizieux L, Gresti J, Djaouti L, Gaba L, Vergès B, Degrace P. Antagonism of peripheral hepatic cannabinoid receptor-1 improves liver lipid metabolism in mice: evidence from cultured explants. Hepatology 2012; 55:790-9. [PMID: 21987372 DOI: 10.1002/hep.24733] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Accepted: 09/26/2011] [Indexed: 12/07/2022]
Abstract
UNLABELLED It is well established that inactivation of the central endocannabinoid system (ECS) through antagonism of cannabinoid receptor 1 (CB1R) reduces food intake and improves several pathological features associated with obesity, such as dyslipidemia and liver steatosis. Nevertheless, recent data indicate that inactivation of peripheral CB1R could also be directly involved in the control of lipid metabolism independently of central CB1R. To further investigate this notion, we tested the direct effect of the specific CB1R antagonist, SR141716, on hepatic carbohydrate and lipid metabolism using cultured liver slices. CB1R messenger RNA expression was strongly decreased by SR141716, whereas it was increased by the CB1R agonist, arachidonic acid N-hydroxyethylamide (AEA), indicating the effectiveness of treatments in modulating ECS activity in liver explants both from lean or ob/ob mice. The measurement of O(2) consumption revealed that SR141716 increased carbohydrate or fatty acid utilization, according to the cellular hormonal environment. In line with this, SR141716 stimulated ß-oxidation activity, and the role of CB1R in regulating this pathway was particularly emphasized when ECS was hyperactivated by AEA and in ob/ob tissue. SR141716 also improved carbohydrate and lipid metabolism, blunting the AEA-induced increase in gene expression of proteins related to lipogenesis. In addition, we showed that SR141716 induced cholesterol de novo synthesis and high-density lipoprotein uptake, revealing a relationship between CB1R and cholesterol metabolism. CONCLUSION These data suggest that blocking hepatic CB1R improves both carbohydrate and lipid metabolism and confirm that peripheral CB1R should be considered as a promising target to reduce cardiometabolic risk in obesity.
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Affiliation(s)
- Tony Jourdan
- UMR 866 INSERM-UB, Team Physiopathology of Dyslipidemia, Faculty of Sciences, Dijon, France
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7
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McCarty MF. Full-spectrum antioxidant therapy featuring astaxanthin coupled with lipoprivic strategies and salsalate for management of non-alcoholic fatty liver disease. Med Hypotheses 2011; 77:550-6. [DOI: 10.1016/j.mehy.2011.06.029] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Revised: 06/09/2011] [Accepted: 06/12/2011] [Indexed: 12/13/2022]
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Reuter SE, Evans AM. Long-chain acylcarnitine deficiency in patients with chronic fatigue syndrome. Potential involvement of altered carnitine palmitoyltransferase-I activity. J Intern Med 2011; 270:76-84. [PMID: 21205027 DOI: 10.1111/j.1365-2796.2010.02341.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE The underlying aetiology of chronic fatigue syndrome is currently unknown; however, in the light of carnitine's critical role in mitochondrial energy production, it has been suggested that chronic fatigue syndrome may be associated with altered carnitine homeostasis. This study was conducted to comparatively examine full endogenous carnitine profiles in patients with chronic fatigue syndrome and healthy controls. DESIGN A cross-sectional, observational study. SETTING AND SUBJECTS Forty-four patients with chronic fatigue syndrome and 49 age- and gender-matched healthy controls were recruited from the community and studied at the School of Pharmacy & Medical Sciences, University of South Australia. MAIN OUTCOME MEASURES All participants completed a fatigue severity scale questionnaire and had a single fasting blood sample collected which was analysed for l-carnitine and 35 individual acylcarnitine concentrations in plasma by LC-MS/MS. RESULTS Patients with chronic fatigue syndrome exhibited significantly altered concentrations of C8:1, C12DC, C14, C16:1, C18, C18:1, C18:2 and C18:1-OH acylcarnitines; of particular note, oleyl-L-carnitine (C18:1) and linoleyl-L-carnitine (C18:2) were, on average, 30-40% lower in patients than controls (P < 0.0001). Significant correlations between acylcarnitine concentrations and clinical symptomology were also demonstrated. CONCLUSIONS It is proposed that this disturbance in carnitine homeostasis is reflective of a reduction in carnitine palmitoyltransferase-I (CPT-I) activity, possibly a result of the accumulation of omega-6 fatty acids previously observed in this patient population. It is hypothesized that the administration of omega-3 fatty acids in combination with l-carnitine would increase CPT-I activity and improve chronic fatigue syndrome symptomology.
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Affiliation(s)
- S E Reuter
- From the School of Pharmacy & Medical Sciences, University of South Australia, Adelaide, SA, Australia.
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9
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Degrace P, Demizieux L, Du ZY, Gresti J, Caverot L, Djaouti L, Jourdan T, Moindrot B, Guilland JC, Hocquette JF, Clouet P. Regulation of Lipid Flux between Liver and Adipose Tissue during Transient Hepatic Steatosis in Carnitine-depleted Rats. J Biol Chem 2007; 282:20816-26. [PMID: 17496329 DOI: 10.1074/jbc.m611391200] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Rats with carnitine deficiency due to trimethylhydrazinium propionate (mildronate) administered at 80 mg/100 g body weight per day for 10 days developed liver steatosis only upon fasting. This study aimed to determine whether the transient steatosis resulted from triglyceride accumulation due to the amount of fatty acids preserved through impaired fatty acid oxidation and/or from up-regulation of lipid exchange between liver and adipose tissue. In liver, mildronate decreased the carnitine content by approximately 13-fold and, in fasted rats, lowered the palmitate oxidation rate by 50% in the perfused organ, increased 9-fold the triglyceride content, and doubled the hepatic very low density lipoprotein secretion rate. Concomitantly, triglyceridemia was 13-fold greater than in controls. Hepatic carnitine palmitoyltransferase I activity and palmitate oxidation capacities measured in vitro were increased after treatment. Gene expression of hepatic proteins involved in fatty acid oxidation, triglyceride formation, and lipid uptake were all increased and were associated with increased hepatic free fatty acid content in treated rats. In periepididymal adipose tissue, mildronate markedly increased lipoprotein lipase and hormone-sensitive lipase activities in fed and fasted rats, respectively. On refeeding, carnitine-depleted rats exhibited a rapid decrease in blood triglycerides and free fatty acids, then after approximately 2 h, a marked drop of liver triglycerides and a progressive decrease in liver free fatty acids. Data show that up-regulation of liver activities, peripheral lipolysis, and lipoprotein lipase activity were likely essential factors for excess fat deposit and release alternately occurring in liver and adipose tissue of carnitine-depleted rats during the fed/fasted transition.
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Affiliation(s)
- Pascal Degrace
- UMR 866 INSERM-UB, Equipe Physiopathologie des dyslipidémies, Faculté des Sciences, 21000 Dijon, France
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10
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Ota N, Soga S, Hase T, Tokimitsu I, Murase T. Dietary diacylglycerol induces the regression of atherosclerosis in rabbits. J Nutr 2007; 137:1194-9. [PMID: 17449581 DOI: 10.1093/jn/137.5.1194] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Recent studies of the relation between serum triacylglycerol concentration and the risk for coronary artery disease suggest that inefficient clearance of postprandial triacylglycerols promotes atherogenesis. We recently demonstrated that dietary diacylglycerol (DAG), rich in the 1,3-species, suppresses the postprandial increase in serum triacylglycerol levels compared with dietary triacylglycerol (TAG). Here, we investigated the effects of dietary DAG on atherosclerosis in rabbits with cholesterol-induced atherosclerosis. New Zealand White rabbits (n = 20) were fed a diet containing 3% lard and 1.3% cholesterol for 50 d to induce atherosclerotic lesions. Thereafter, the rabbits were assigned to 2 groups and fed 90 g/d nonpurified diet and orally administered 5 g DAG or TAG for an additional 34 d. Reference rabbits (n = 5) were fed only the nonpurified diet throughout the 84-d study. The area of atherosclerotic lesions and aortic lipid concentrations were significantly lower in DAG-fed rabbits compared with TAG-fed rabbits. The VLDL receptor and macrophage antigen-1 mRNA expression levels were significantly lower in DAG-fed rabbits than in TAG-fed rabbits. In the liver of DAG-fed rabbits, the triacylglycerol concentration was lower and the carnitine palmitoyltransferase activity higher than in TAG-fed rabbits. Stimulation of hepatic lipid catabolism might be related to the reduced lipid accumulation in the liver and aorta by reducing the release of triacylglycerol into the circulation. Thus, long-term consumption of DAG, which reduces postprandial lipemia, might be useful for the regression of atherosclerosis by stimulating hepatic lipid catabolism and thereby modulating monocyte/macrophage migration and aortic lipid accumulation.
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Affiliation(s)
- Noriyasu Ota
- Biological Science Laboratories, Kao Corporation, Tochigi 321-3497, Japan.
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11
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Degrace P, Moindrot B, Mohamed I, Gresti J, Clouet P. Moderate consumption of beer reduces liver triglycerides and aortic cholesterol deposit in LDLr−/− apoB100/100 mice. Atherosclerosis 2006; 189:328-35. [PMID: 16487531 DOI: 10.1016/j.atherosclerosis.2006.01.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2005] [Revised: 01/11/2006] [Accepted: 01/16/2006] [Indexed: 10/25/2022]
Abstract
This study was designed to address the effects of a moderate consumption of beer on serum and liver lipid parameters and on the development of aortic lesions in a mouse model associated with a human atherogenic lipoprotein profile. LDLr(-/-) apoB(100/100) mice received each day during 12 weeks either water, mild beer (0.570g of ethanol/kg of body weight) or ethanol-free beer in a single pure dose. Serum and liver lipid parameters were analyzed and atherosclerotic lesions were estimated in heart and aorta through their total cholesterol content. mRNA levels of enzymes and receptors involved in lipoprotein uptake, in fatty acid esterification and oxidation, and in reverse cholesterol transport were also measured in the liver. Serum glucose, triglyceride (TG) and cholesterol levels were altered neither by ethanol-free beer nor by mild beer. Nevertheless, both beer treatments significantly increased HDL-cholesterol (HDL-C) and VLDL-C levels by reference to controls with no change in LDL-C levels. Liver TG contents were significantly decreased by either beer treatment. Cholesterol accumulation was attenuated in the whole aorta of mice treated with mild beer at p<0.05 and not significantly with ethanol-free beer. Heart cholesterol contents were comparable in the three series. Among the genes studied, only scavenger receptor-B1 was downregulated by both beer-based beverages. LDL receptor related protein, lecithin-cholesterol acyltransferase and sterol regulatory element-binding protein 2 were downregulated only by mild beer. The expression of other genes assayed was not altered. When administered in chronic and moderate dose, unidentified components of beer may exert beneficial effects towards atherosclerosis development through alteration of lipoprotein metabolism in LDLr(-/-) apoB(100/100) mice. This effect was slightly amplified by the presence of ethanol in beer.
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MESH Headings
- Alcohol Drinking
- Animals
- Aorta, Thoracic/metabolism
- Aortic Diseases/metabolism
- Aortic Diseases/prevention & control
- Apolipoproteins B/deficiency
- Atherosclerosis/metabolism
- Atherosclerosis/prevention & control
- Beer
- Cholesterol, HDL/metabolism
- Cholesterol, LDL/metabolism
- Cholesterol, VLDL/metabolism
- Chromatography, High Pressure Liquid
- Down-Regulation
- Female
- Liver/metabolism
- Mice
- Mice, Inbred C57BL
- Mitochondria, Liver/metabolism
- Oxidation-Reduction
- Palmitates/metabolism
- Phosphatidylcholine-Sterol O-Acyltransferase/genetics
- Polymerase Chain Reaction
- RNA, Messenger/genetics
- Receptors, LDL/deficiency
- Receptors, LDL/genetics
- Scavenger Receptors, Class B/genetics
- Sterol Regulatory Element Binding Protein 2/genetics
- Triglycerides/metabolism
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Affiliation(s)
- Pascal Degrace
- UPRES Lipides et Nutrition EA2422, Faculté des Sciences Gabriel, Université de Bourgogne, 6 Bd Gabriel, 21000 Dijon, France.
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Abstract
PURPOSE OF REVIEW Fish oils rich in n-3 fatty acids reduce serum triglyceride levels. This well known effect has been shown to be caused by decreased very low-density lipoprotein triglyceride secretion rates in kinetic studies in humans. Animal studies have explored the biochemical mechanisms underlying this effect. Triglyceride synthesis could be reduced by n-3 fatty acids in three general ways: reduced substrate (i.e. fatty acids) availability, which could be secondary to increase in beta-oxidation, decreased free fatty acids delivery to the liver, decreased hepatic fatty acids synthesis; increased phospholipid synthesis; or decreased activity of triglyceride-synthesizing enzymes (diacylgylcerol acyltranferase or phosphatidic acid phosphohydrolase). RECENT FINDINGS Rarely were experimental conditions used in rat studies physiologically relevant to the human situation in which 1.2% energy as n-3 fatty acids lowers serum triglyceride levels. Nevertheless, the most consistent effect of n-3 fatty acids feeding in rats is to decrease lipogenesis. Increased beta-oxidation was frequently, but not consistently, reported with similar numbers of studies reporting increased mitochondrial compared with peroxisomal oxidation. Inhibition of triglyceride-synthesizing enzymes was only occasionally noted. SUMMARY As the vast majority of studies fed unphysiologically high doses of n-3 fatty acids, these findings in rats must be considered tentative, and the mechanism by which n-3 fatty acids reduce triglyceride levels in humans remains speculative.
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Gaíva MH, Couto RC, Oyama LM, Couto GEC, Silveira VLF, Ribeiro EB, Nascimento CMO. Diets rich in polyunsaturated fatty acids: effect on hepatic metabolism in rats. Nutrition 2003; 19:144-9. [PMID: 12591547 DOI: 10.1016/s0899-9007(02)00909-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE We investigated the effect of diets rich in omega-6 and omega-3 fatty acids on hepatic metabolism. METHODS Male Wistar rats, just weaned, were fed ad libitum for 8 wk with one of the following diets: rat chow (C), rat chow containing 15% (w/w) soybean oil (S), rat chow containing 15% (w/w) fish oil (F), and rat chow containing 15% soy bean and fish oil (SF; 5:1, w/w). Casein was added to the fatty diets to achieve the same content of protein (20%) as the control chow. The rats were killed by decapitation, and the hepatic tissue was removed and weighed. Tissue lipid, glycogen, and protein content, in vivo lipogenesis rate, and adenosine triphosphate citrate lyase and malic enzyme activities were evaluated. Plasma total lipids, triacylglycerol, and cholesterol concentrations were assessed. RESULTS Body weight gain was higher in F and SF than in C and S rats. Liver weight, lipid content, and lipogenesis rate increased in F and SF rats, although adenosine triphosphate citrate lyase activity decreased. Glycogen concentration decreased in S, F, and SF rats compared with C rats. Plasma total lipids and triacylglycerol concentrations were lower in F and SF than in C rats. Total and high-density lipoprotein cholesterol (HDL-C) plasma levels decreased in F rats, with maintenance of the total:HDL-C ratio. In SF rats, an increase in HDL-C led to a lower total:HDL-C ratio. CONCLUSIONS These results indicated that an enrichment of the diet with omega-3 polyunsaturated fatty acids produces hypolipidemia but may cause changes in liver metabolism that favor lipid deposition. They also suggested that the addition of a small amount of eicosapentaenoic and docosahexaenoic polyunsaturated fatty acids to an omega-6-rich diet further improve the circulating lipid profile, in comparison with an omega-3-rich diet, but it does not prevent excess liver lipid accumulation.
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Affiliation(s)
- Maria Helena Gaíva
- Department of Physiology, Division of Neurophysiology and Endocrine Physiology, São Paulo Federal University, São Paulo, Brazil
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Murase T, Nagasawa A, Suzuki J, Wakisaka T, Hase T, Tokimitsu I. Dietary alpha-linolenic acid-rich diacylglycerols reduce body weight gain accompanying the stimulation of intestinal beta-oxidation and related gene expressions in C57BL/KsJ-db/db mice. J Nutr 2002; 132:3018-22. [PMID: 12368389 DOI: 10.1093/jn/131.10.3018] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Dietary fat contributes to the development of obesity. We examined the effect of dietary diacylglycerol (DG), which is a minor component of edible oils, on the development of obesity and expression of genes involved in energy homeostasis in C57BL/KsJ-db/db mice. Mice were fed diets containing either 14 g/100 g (%) triacylglycerol (TG), 10% TG + 4% alpha-linolenic acid-rich TG (ALATG), or 10% TG + 4% alpha-linolenic acid-rich diacylglycerol (ALADG) for 1 mo. Mice fed ALADG, but not ALATG had less body weight gain and higher rectal temperature than the TG-fed controls. These effects were accompanied by up-regulation of acyl-CoA oxidase, medium-chain acyl-CoA dehydrogenase, fatty acid binding protein, and uncoupling protein (UCP)-2 mRNA and beta-oxidation activity in the small intestine. In contrast, the treatments did not affect beta-oxidation and related gene expressions in the liver or UCP-3 mRNA level in skeletal muscle. These results indicate that stimulation of lipid metabolism in the small intestine might be closely related to the antiobesity and thermogenic effects of dietary DG. In addition, structural differences between DG and TG, not variations in the composition of fatty acids, are responsible for the different effects of the lipids.
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Affiliation(s)
- Takatoshi Murase
- Biological Science Laboratories, Kao Corporation, Ichikai, Haga, Tochigi 321-3497, Japan
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de Brouwer APM, Westerman J, Kleinnijenhuis A, Bevers LE, Roelofsen B, Wirtz KWA. Clofibrate-induced relocation of phosphatidylcholine transfer protein to mitochondria in endothelial cells. Exp Cell Res 2002; 274:100-11. [PMID: 11855861 DOI: 10.1006/excr.2001.5460] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The phosphatidylcholine transfer protein (PC-TP) is a specific transporter of phosphatidylcholine (PC) between membranes. To get more insight into its physiological function, we have studied the localization of PC-TP by microinjection of fluorescently labeled PC-TP in foetal bovine heart endothelial (FBHE) cells and by expression of an enhanced yellow fluorescent protein-PC-TP fusion protein in FBHE cells, human umbilical vein endothelial cells, and HepG2 cells. Analysis by confocal laser scanning microscopy showed that PC-TP was evenly distributed throughout the cytosol with an apparently elevated level in nuclei. By measuring the fluorescence recovery after bleaching it was established that PC-TP is highly mobile throughout the cell, with its transport into the nucleus being hindered by the nuclear envelope. Given the proposed function of PC-TP in lipid metabolism, we have tested a number of compounds (phorbol ester, bombesin, A23187, thrombin, dibutyryl cyclic AMP, oleate, clofibrate, platelet-derived growth factor, epidermal growth factor, and hydrogen peroxide) for their ability to affect intracellular PC-TP distribution. Only clofibrate (100 microM) was found to have an effect, with PC-TP moving to mitochondria within 5 min of stimulation. This relocation did not occur with PC-TP(S110A), lacking the putative protein kinase C (PKC)-dependent phosphorylation site, and was restricted to the primary endothelial cells. Relocation did not occur in HepG2 cells, possibly due to the fact that clofibrate does not induce PKC activation in these cells.
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Affiliation(s)
- A P M de Brouwer
- Department of Biochemistry of Lipids, Institute of Biomembranes, Padualaan 8, Utrecht, 3584 CH, The Netherlands.
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16
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Murase T, Mizuno T, Omachi T, Onizawa K, Komine Y, Kondo H, Hase T, Tokimitsu I. Dietary diacylglycerol suppresses high fat and high sucrose diet-induced body fat accumulation in C57BL/6J mice. J Lipid Res 2001. [DOI: 10.1016/s0022-2275(20)31661-8] [Citation(s) in RCA: 192] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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17
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Abstract
The cost of living can be measured as an animal's metabolic rate. Basal metabolic rate (BMR) is factorially related to other metabolic rates. Analysis of BMR variation suggests that metabolism is a series of linked processes varying in unison. Membrane processes, such as maintenance of ion gradients, are important costs and components of BMR. Membrane bilayers in metabolically active systems are more polyunsaturated and less monounsaturated than metabolically less-active systems. Such polyunsaturated membranes have been proposed to result in an increased molecular activity of membrane proteins, and in this manner the amount of membrane and its composition can act as a pacemaker for metabolism. The potential importance of membrane acyl composition in metabolic depression, hormonal control of metabolism, the evolution of endothermy, as well as its implications for lifespan and human health, are briefly discussed.
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Affiliation(s)
- A J Hulbert
- Department of Biological Science, University of Wollongong, NSW, Australia.
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18
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Effect of dietary fish oil on the sensitivity of hepatic lipid metabolism to regulation by insulin. J Lipid Res 2000. [DOI: 10.1016/s0022-2275(20)32380-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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19
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Tsoko M, Beauseigneur F, Gresti J, Demarquoy J, Clouet P. Hypolipidaemic effects of fenofibrate are not altered by mildronate-mediated normalization of carnitine concentration in rat liver. Biochimie 1998; 80:943-8. [PMID: 9893954 DOI: 10.1016/s0300-9084(00)88891-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The five-fold higher carnitine content in the liver of fenofibrate-treated rats addresses the question about the possible role of this enhancement in the hypolipidaemic effect of the drug and the underlying mechanisms. When fenofibrate was administered with mildronate (a gamma-butyrobetaine hydroxylase inhibitor) in suitable amount, the content in carnitine was found to be normalized in liver. However, triglyceride contents of liver and serum were then at least as low as in rats treated by fenofibrate only. When carnitine concentration was lowered by mildronate to the third of the normal value, a marked increase in triglycerides occurred both in liver and serum, while the five-fold increase in carnitine due to fenofibrate enhanced blood ketone body concentration with no effect on liver and serum triglycerides. Data suggest that the normal carnitine concentration is largely sufficient to meet the usual requirement for carnitine palmitoyltransferase I activity (CPT I). In rat liver, increase in mitochondrial CPT I activity and in peroxisomal fatty acid oxidation may constitute part of the hypolipidaemic effect of fenofibrate.
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Affiliation(s)
- M Tsoko
- Laboratoire de Nutrition Cellulaire et Métabolique, UPRES 2422, Université de Bourgogne, Faculté des Sciences, Dijon, France
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20
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Ling PR, Boyce P, Bistrian BR. Role of arachidonic acid in the regulation of the inflammatory response in TNF-alpha-treated rats. JPEN J Parenter Enteral Nutr 1998; 22:268-75. [PMID: 9739028 DOI: 10.1177/0148607198022005268] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND This study examined whether adding arachidonic acid (AA) to a fish oil diet would alter certain of the anti-inflammatory effects of fish oil in response to tumor necrosis factor (TNF) infusion in rats. METHODS AA was given at 0.08 wt% of diet for 6 weeks. The total fat in each diet provided 20% of dietary energy. Four groups were pair-fed sunflower oil (S), S+AA, fish oil (F), or F+AA for 6 weeks. At the end of feeding, each animal received TNF-alpha (20 microg/kg) infusion for 3 hours. After 1 hour of TNF infusion, a euglycemic and hyperinsulinemic clamp (10 mU/min per kilogram of insulin) was used to determine the actions of insulin. The insulin-stimulated glucose utilization in liver, muscle, and fat was determined by using 14C-deoxyglucose. The plasma glucose, insulin, and corticosterone levels were determined at basal, 60 minutes, and the end of the experiment (180 minutes). The fatty acid composition of plasma phospholipids also was determined. RESULTS Fish oil significantly increased omega-3 fatty acids in phospholipids in both F and F+AA and decreased AA in F, compared with S. AA significantly restored the level of AA and reduced the increase of omega-3 fatty acids in phospholipids in F+AA compared with F, but had no impact on fatty acid composition when added to S. Corticosterone level was significantly lower with fish oil feeding but higher in both F and S containing AA compared with F and S, respectively. The highest glucose uptake in tissues was in F, followed by F+AA, and then S and S+AA. CONCLUSIONS These results suggest that fish oil is anti-inflammatory principally through a reduction in the AA content of phospholipids.
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Affiliation(s)
- P R Ling
- Nutrition/Infection Laboratory, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
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21
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Colquhoun A, Curi R. Effects of saturated and polyunsaturated fatty acids on human tumor-cell proliferation. GENERAL PHARMACOLOGY 1998; 30:191-4. [PMID: 9502173 DOI: 10.1016/s0306-3623(97)00110-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
1. Fatty acids of varying chain length and degree of unsaturation were found to inhibit the proliferation of T24/83, Hep2 and LLC-WRC256 tumor cell lines. 2. There was a strong correlation (r2= -0.956 to -0.995) between the degree of inhibition of proliferation and the degree of unsaturation of 18-carbon fatty acids for all the cell lines studied. No correlation existed in this respect for the 20-carbon fatty acids. 3. Tumor cells can differentiate between the degree of unsaturation of the 18-carbon fatty acids, and this ability is ultimately manifested in the rate of proliferation; however, the mechanisms remain to be identified.
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Affiliation(s)
- A Colquhoun
- Departamento de Fisiologia e Biofisica, Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil
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22
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Dietary arachidonic acid and hepatic desaturation of fatty acids in obese zucker rats. J AM OIL CHEM SOC 1998. [DOI: 10.1007/s11746-998-0041-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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23
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Power GW, Newsholme EA. Dietary fatty acids influence the activity and metabolic control of mitochondrial carnitine palmitoyltransferase I in rat heart and skeletal muscle. J Nutr 1997; 127:2142-50. [PMID: 9349840 DOI: 10.1093/jn/127.11.2142] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The fatty acid composition of the diet has been found to influence the activity and sensitivity of mitochondrial carnitine palmitoyltransferase I (CPT I; EC 2.3.1.21) to inhibition by malonyl CoA in rat heart and skeletal muscle. The nutritional state of rats has been shown to have less influence on the activity and metabolic control of mitochondrial CPT I in heart and skeletal muscle tissue than in the liver, a tissue in which CPT I activity and sensitivity to inhibition by malonyl CoA can be shown to be regulated acutely under different nutritional conditions. However, because manipulation of the nutritional state in these previous studies was restricted mainly to examining the effect of starvation, this study was undertaken to determine whether, as in liver, the fatty acid content and composition of the diet can regulate the activity and metabolic control of CPT I in heart and skeletal muscle. Rats were fed for up to 10 wk either a nonpurified low fat diet (30 g fat/kg) or a high fat diet (200 g fat/kg) containing one of the following five oil types: hydrogenated coconut oil (HCO), olive oil (OO), safflower oil (SO), evening primrose oil (EPO) or menhaden (fish) oil (MO). Feeding a diet enriched in MO had the most pronounced effect. Rats fed MO had a significantly greater skeletal muscle CPT I specific activity and tissue capacity, and a lower sensitivity of CPT I to malonyl CoA inhibition compared with rats fed a low fat diet, but the duration of feeding required to modulate this sensitivity was longer than that observed previously for the liver enzyme. Progressively greater sensitivity of heart CPT I to malonyl CoA occurred with feeding duration in all groups. These studies indicate that the fatty acid composition of the diet is involved in the regulation of mitochondrial CPT I activity in heart and skeletal muscle.
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Affiliation(s)
- G W Power
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
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24
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Beauseigneur F, Goubern M, Chapey MF, Gresti J, Vergely C, Tsoko M, Demarquoy J, Rochette L, Clouet P. F1F0-ATPase, early target of the radical initiator 2,2'-azobis-(2-amidinopropane) dihydrochloride in rat liver mitochondria in vitro. Biochem J 1996; 320 ( Pt 2):571-6. [PMID: 8973568 PMCID: PMC1217967 DOI: 10.1042/bj3200571] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This study was designed to determine which enzyme activities were first impaired in mitochondria exposed to 2,2'-azobis-(2-amidinopropane) dihydrochloride (AAPH), a known radical initiator. EPR spin-trapping revealed generation of reactive oxygen species although malondialdehyde formation remained very low. With increasing AAPH concentrations, State-3 respiration was progressively depressed with unaltered ADP/O ratios. A top-down approach demonstrated that alterations were located at the phosphorylation level. As shown by inhibitor titrations, ATP/ADP translocase activity was unaffected in the range of AAPH concentrations used. In contrast, AAPH appeared to exert a deleterious effect at the level of F1F0-ATPase, comparable with dicyclohexylcarbodi-imide, which alters Fo proton channel. A comparison of ATP hydrolase activity in uncoupled and broken mitochondria reinforced this finding. In spite of its pro-oxidant properties, AAPH was shown to act as a dose-dependent inhibitor of cyclosporin-sensitive permeability transition initiated by Ca2+, probably as a consequence of its effect on F1F0-ATPase. Resveratrol, a potent antiperoxidant, completely failed to prevent the decrease in State-3 respiration caused by AAPH. The data suggest that AAPH, when used under mild conditions, acted as a radical initiator and was capable of damaging F1F0-ATPase, thereby slowing respiratory chain activity and reducing mitochondrial antioxidant defences.
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25
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Stimulation of the activities of hepatic fatty acid oxidation enzymes by dietary fat rich in alpha-linolenic acid in rats. J Lipid Res 1996. [DOI: 10.1016/s0022-2275(20)37590-8] [Citation(s) in RCA: 81] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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26
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Clouet P, Niot I, Gresti J, Demarquoy J, Boichot J, Durand G, Bézard J. Polyunsaturated n-3 and n-6 fatty acids at a low level in the diet alter mitochondrial outer membrane parameters in Wistar rat liver. J Nutr Biochem 1995. [DOI: 10.1016/0955-2863(95)00123-h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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27
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Cao JM, Blond JP, Juaneda P, Durand G, Bézard J. Effect of low levels of dietary fish oil on fatty acid desaturation and tissue fatty acids in obese and lean rats. Lipids 1995; 30:825-32. [PMID: 8577226 DOI: 10.1007/bf02533958] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The effect of very low levels of dietary long-chain n-3 fatty acids on delta 6 desaturation of linoleic acid (18:2n-6) and alpha-linolenic acid (18:3n-3), and on delta 5 desaturation of dihomo-gamma-linolenic acid (20:3n-6), in liver microsomes and its influence on tissue fatty acids were examined in obese and lean Zucker rats and in Wistar rats. Animals fed for 12 wk a balanced diet containing ca. 200 mg of long-chain polyunsaturated n-3 fatty acids per 100 g of diet were compared to those fed the same amount of alpha-linolenic acid. Low amounts of long-chain n-3 fatty acids greatly inhibited delta 6 desaturation of 18:2n-6 and delta 5 desaturation of 20:3n-6, while delta 6 desaturation of 18:3n-3 was not inhibited in Zucker rats and was even stimulated in Wistar rats. Inhibition of the biosynthesis of long-chain n-6 fatty acids was reflected in a decrease in arachidonic acid (20:4n-6) content of serum lipids when fasting, and also in the phospholipid fatty acids of liver microsomes. On the contrary, heart and kidney phospholipids did not develop any decrease in 20:4n-6 during fish oil ingestion. Docosahexaenoic acid (22:6n-3), present in the dietary fish oil, was increased in serum lipids and in liver microsome, heart, and kidney phospholipids.
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Affiliation(s)
- J M Cao
- Unité de Nutrition Cellulaire et Métabolique, Université de Bourgogne, Dijon, France
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28
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Tsoko M, Beauseigneur F, Gresti J, Niot I, Demarquoy J, Boichot J, Bezard J, Rochette L, Clouet P. Enhancement of activities relative to fatty acid oxidation in the liver of rats depleted of L-carnitine by D-carnitine and a gamma-butyrobetaine hydroxylase inhibitor. Biochem Pharmacol 1995; 49:1403-10. [PMID: 7763283 DOI: 10.1016/0006-2952(95)00019-v] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
This study was designed to examine whether the depletion of L-carnitine may induce compensatory mechanisms allowing higher fatty acid oxidative activities in liver, particularly with regard to mitochondrial carnitine palmitoyltransferase I activity and peroxisomal fatty acid oxidation. Wistar rats received D-carnitine for 2 days and 3-(2,2,2,-trimethylhydrazinium)propionate (mildronate), a noncompetitive inhibitor of gamma-butyrobetaine hydroxylase, for 10 days. They were starved for 20 hr before being sacrificed. A dramatic reduction in carnitine concentration was observed in heart, skeletal muscles and kidneys, and to a lesser extent, in liver. Triacylglycerol content was found to be significantly more elevated on a gram liver and whole liver basis as well as per mL of blood (but to a lesser extent), while similar concentrations of ketone bodies were found in the blood of D-carnitine/mildronate-treated and control rats. In liver mitochondria, the specific activities of acyl-CoA synthetase and carnitine palmitoyltransferase I were enhanced by the treatment, while peroxisomal fatty acid oxidation was higher per gram of tissue. It is suggested that there may be an enhancement of cellular acyl-CoA concentration, a signal leading to increased liver fatty acid oxidation in acute carnitine deficiency.
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Affiliation(s)
- M Tsoko
- Laboratoire de Nutrition Cellulaire et Métabolique, EA DRED 564, Faculté des Sciences, Dijon, France
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29
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Whelan J, Surette ME, Li-Stiles B, Bailey JW. Evidence that dietary arachidonic acid increases circulating triglycerides. Lipids 1995; 30:425-9. [PMID: 7637562 DOI: 10.1007/bf02536300] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Male Syrian hamsters and male CD-1 mice were fed diets supplemented with ethyl esters of oleic, linoleic, arachidonic, and eicosapentaenoic acids (1.1-5%, w/w) for 3-4 wk. Plasma and serum triglycerides were significantly higher in the arachidonic acid-supplemented animals compared to those in the other supplementation groups. Changes in serum insulin and glucose levels did not appear to be related to the changes in circulating triglycerides observed in the arachidonic acid-supplemented group. These data indicate that dietary arachidonic acid elevates circulating triglyceride levels compared to other unsaturated fatty acids in hamsters and mice by unknown mechanisms.
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Affiliation(s)
- J Whelan
- Department of Nutrition, University of Tennessee, Knoxville 37996-1900, USA
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