1
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Zhang Y, Kalpio M, Tao L, Haraldsson GG, Guðmundsson HG, Fang X, Linderborg KM, Zhang Y, Yang B. Metabolic fate of DHA from regio- and stereospecific positions of triacylglycerols in a long-term feeding trial in rats. Food Res Int 2023; 174:113626. [PMID: 37986478 DOI: 10.1016/j.foodres.2023.113626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/19/2023] [Accepted: 10/21/2023] [Indexed: 11/22/2023]
Abstract
This study investigated the impact of regio- and stereospecific position of docosahexaenoic acid (DHA) in dietary triacylglycerols (TAGs) on the fatty acid composition of tissues and organs in rats. Four-week feeding with TAGs containing DHA in sn-1, 2, or 3 position and palmitic acid in the remaining positions at a daily dosage of 500 mg TAG/kg body weight significantly increased the DHA content in all organs and tissues in rats, except in the brain, where the change in DHA level was not statistically significant. The group fed sn-1 DHA showed a significantly higher content of DHA in the plasma TAG than the group fed sn-3 DHA. The sn-3 DHA group had higher levels of DHA in the visceral fat compared to the sn-1, sn-2, as well as all other groups. This is the first study showing that DHA from sn-1 and sn-3 positions of dietary TAGs have differential accumulation in tissues. The new findings improved the current knowledge on the significance of TAG isomeric structure for the bioavailability and metabolic fate of DHA.
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Affiliation(s)
- Yuqing Zhang
- Food Sciences, Department of Life Technologies, University of Turku, Turku, Finland
| | - Marika Kalpio
- Food Sciences, Department of Life Technologies, University of Turku, Turku, Finland
| | - Lingwei Tao
- Department of Nutrition & Food Hygiene, School of Public Health, Peking University Health Science Center, Beijing, China
| | | | | | - Xiangrong Fang
- Food Sciences, Department of Life Technologies, University of Turku, Turku, Finland
| | - Kaisa M Linderborg
- Food Sciences, Department of Life Technologies, University of Turku, Turku, Finland
| | - Yumei Zhang
- Department of Nutrition & Food Hygiene, School of Public Health, Peking University Health Science Center, Beijing, China
| | - Baoru Yang
- Food Sciences, Department of Life Technologies, University of Turku, Turku, Finland.
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2
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Wang X, Jin M, Cheng X, Hu X, Zhao M, Yuan Y, Sun P, Jiao L, Tocher DR, Betancor MB, Zhou Q. Lipidomic profiling reveals molecular modification of lipids in hepatopancreas of juvenile mud crab (Scylla paramamosain) fed with different dietary DHA/EPA ratios. Food Chem 2022; 372:131289. [PMID: 34818734 DOI: 10.1016/j.foodchem.2021.131289] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 09/27/2021] [Accepted: 09/29/2021] [Indexed: 12/16/2022]
Abstract
Untargeted lipidomic analysis was conducted to explore how different dietary docosahexaenoic acid (DHA)/eicosapentaenoic acid (EPA) ratio and, specifically, how an optimal ratio (2.3) compared to a suboptimum ratio (0.6) impacted lipid molecular species and the positional distribution of fatty acids in hepatopancreas of mud crab. The results indicated that major category of lipid affected by dietary DHA/EPA ratio was glycerophospholipids (GPs). The optimum dietary DHA/EPA ratio increased the contents of DHA bound to the sn-2 and sn-3 positions of phosphatidylcholine (PC) and triacylglycerol, EPA bound to the sn-2 position of phosphatidylcholine and 18:2n-6 bound to the sn-2 position of phosphatidylethanolamine (PE). Increased dietary DHA/EPA ratio also led to competition between arachidonic acid (ARA) and 18:2n-6 bound to esterified sites. Appropriate dietary DHA/EPA ratio can not only improve the growth performance and nutritional quality of mud crab, but also provide higher quality products for human consumers.
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Affiliation(s)
- Xuexi Wang
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Min Jin
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo 315211, China.
| | - Xin Cheng
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Xiaoying Hu
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Mingming Zhao
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Ye Yuan
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Peng Sun
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Lefei Jiao
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Douglas R Tocher
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Sciences, Shantou University, Shantou 515063, China
| | - Mónica B Betancor
- Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling, Stirling FK9 4LA, United Kingdom
| | - Qicun Zhou
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo 315211, China.
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3
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Bai F, Wang X, Niu X, Shen G, Ye J. Lipidomic Profiling Reveals the Reducing Lipid Accumulation Effect of Dietary Taurine in Groupers ( Epinephelus coioides). Front Mol Biosci 2022; 8:814318. [PMID: 35004860 PMCID: PMC8740052 DOI: 10.3389/fmolb.2021.814318] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Accepted: 11/29/2021] [Indexed: 11/13/2022] Open
Abstract
A lipidomic analysis was conducted to provide the first detailed overview of lipid molecule profiles in response to dietary lipid and taurine and associations of liver lipid-lowering effects of dietary taurine with lipid molecular species and the positional distributions of fatty acids in the liver of juvenile orange-spotted groupers (Epinephelus coioides). The results indicated that the liver was more sensitive to varied dietary lipid and taurine contents than the muscle with regard to lipid molecules. A total of 131 differential lipid molecules (DLMs) were observed in the liver of groupers when dietary taurine was increased from 0 to 1% at 15% lipid, among which all the up and down-regulated DLMs are phospholipids (PLs) and triglycerides (TGs), respectively. The liver content of TGs containing 18:2n-6 attached at the sn-2 and sn-3 positions on the glycerol backbone increased with increasing dietary lipid from 10 to 15% but decreased with increasing dietary taurine from 0 to 1%. Therefore, dietary taurine can not only reduce lipid accumulation through decreasing the contents of TGs containing 18:2n-6 at the sn-2 and sn-3 positions but also enhance the anti-inflammatory capacity and health status of groupers. This study will also provide a new insight into the function of taurine in farmed fish.
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Affiliation(s)
- Fakai Bai
- Xiamen Key Laboratory for Feed Quality Testing and Safety Evaluation, Fisheries College of Jimei University, Xiamen, China
| | - Xuexi Wang
- Key Laboratory of Marine Biotechnology of Fujian Province, Institute of Oceanology, Animal Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xingjian Niu
- Xiamen Key Laboratory for Feed Quality Testing and Safety Evaluation, Fisheries College of Jimei University, Xiamen, China
| | - Guiping Shen
- Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Department of Electronic Science, Xiamen University, Xiamen, China
| | - Jidan Ye
- Xiamen Key Laboratory for Feed Quality Testing and Safety Evaluation, Fisheries College of Jimei University, Xiamen, China
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Liu Y, Jiao JG, Gao S, Ning LJ, Mchele Limbu S, Qiao F, Chen LQ, Zhang ML, Du ZY. Dietary oils modify lipid molecules and nutritional value of fillet in Nile tilapia: A deep lipidomics analysis. Food Chem 2019; 277:515-523. [DOI: 10.1016/j.foodchem.2018.11.020] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 10/19/2018] [Accepted: 11/02/2018] [Indexed: 01/06/2023]
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5
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Luo Y, Zhang Y, Yuan F, Gao B, Wang Z, Yu L(L. Triacylglycerols composition analysis of olive oils by ultra‐performance convergence chromatography combined with quadrupole time‐of‐flight mass spectrometry. Int J Food Sci Technol 2018. [DOI: 10.1111/ijfs.14008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Yinghua Luo
- Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Technology& Business University (BTBU) Beijing 100048 China
- Institute of Food and Nutraceutical Science School of Agriculture & Biology Shanghai Jiao Tong University Shanghai 200240 China
- Department of Nutrition and Food Science University of Maryland College Park MD 20742 USA
| | - Yaqiong Zhang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Technology& Business University (BTBU) Beijing 100048 China
- Institute of Food and Nutraceutical Science School of Agriculture & Biology Shanghai Jiao Tong University Shanghai 200240 China
| | - Fanghao Yuan
- Institute of Food and Nutraceutical Science School of Agriculture & Biology Shanghai Jiao Tong University Shanghai 200240 China
| | - Boyan Gao
- Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Technology& Business University (BTBU) Beijing 100048 China
- Institute of Food and Nutraceutical Science School of Agriculture & Biology Shanghai Jiao Tong University Shanghai 200240 China
- Department of Nutrition and Food Science University of Maryland College Park MD 20742 USA
| | - Ziyuan Wang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Technology& Business University (BTBU) Beijing 100048 China
| | - Liangli (Lucy) Yu
- Department of Nutrition and Food Science University of Maryland College Park MD 20742 USA
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6
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Neuromuscular adaptations to sprint interval training and the effect of mammalian omega-3 fatty acid supplementation. Eur J Appl Physiol 2017; 117:469-482. [DOI: 10.1007/s00421-017-3539-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 01/05/2017] [Indexed: 10/20/2022]
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7
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Wang T, Wang X, Wang X. Effects of Lipid Structure Changed by Interesterification on Melting Property and Lipemia. Lipids 2016; 51:1115-1126. [DOI: 10.1007/s11745-016-4184-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 08/02/2016] [Indexed: 10/21/2022]
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8
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Lewis EJH, Radonic PW, Wolever TMS, Wells GD. 21 days of mammalian omega-3 fatty acid supplementation improves aspects of neuromuscular function and performance in male athletes compared to olive oil placebo. J Int Soc Sports Nutr 2015; 12:28. [PMID: 26085822 PMCID: PMC4470064 DOI: 10.1186/s12970-015-0089-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 06/11/2015] [Indexed: 11/29/2022] Open
Abstract
Background Omega-3 polyunsaturated fatty acids (N-3) are essential nutrients for human health and integral components of neural tissues. There is evidence that N-3 supplementation may benefit exercise performance, however, no study has investigated the ergogenic potential of N-3 supplementation. Our objective was to determine the effect of short-term N-3 supplementation on neuromuscular-function and physical-performance in well-trained athletes. Methods Male athletes (n = 30), 25 years (SD 4.6), training 17 h.wk−1 (SD 5) completed this randomized, placebo-controlled, parallel-design study. At baseline a blood sample was collected, maximal voluntary isometric contractions (MVC) with electromyography (EMG) recordings were measured, and participants underwent various performance tests including a Wingate test and 250 kJ time trial (TT) followed by repeated MVC and EMG measurement. Participants were then randomly assigned to receive N-3 (5 ml seal oil, 375 mg EPA, 230 mg DPA, 510 mg DHA) or placebo (5 ml olive oil) for 21-days after which baseline testing was repeated. The magnitude-based inference approach was used to estimate the probability that N-3 had a beneficial effect on neuromuscular-function and performance of at least ±1 %. Data are shown as mean ± 90 % confidence-interval. Results Plasma EPA was higher on N-3 than placebo (p = 0.004) but the increases in DPA and DHA were not significant (p = 0.087, p = 0.058). N-3 supplementation had an unclear effect on MVC force (4.1 ± 6.6 %) but increased vastus lateralis EMG by 20 ± 18 % vs placebo (very likely beneficial). N-3 supplementation reduced Wingate percent power drop by 4.76 ± 3.4 % vs placebo (very likely beneficial), but the difference in TT performance was unclear (−1.9 ± 4.8 %). Conclusion Our data indicates N-3 PUFA supplementation improved peripheral neuromuscular function and aspects of fatigue with an unclear effect on central neuromuscular function. Clinical trial registration NCT0201433.
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Affiliation(s)
- Evan J H Lewis
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., M5S 3E2 Toronto, Ontario Canada
| | - Peter W Radonic
- Faculty of Kinesiology & Physical Education, University of Toronto, 100 Devonshire Place, M5S 2C9 Toronto, Ontario Canada
| | - Thomas M S Wolever
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., M5S 3E2 Toronto, Ontario Canada
| | - Greg D Wells
- Faculty of Kinesiology & Physical Education, University of Toronto, 100 Devonshire Place, M5S 2C9 Toronto, Ontario Canada ; Department of Physiology and Experimental Medicine, The Hospital for Sick Children, 555 University Ave, M5G 1X8 Toronto, Ontario Canada
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9
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Differential effects of triacylglycerol positional isomers containing n-3 series highly unsaturated fatty acids on lipid metabolism in C57BL/6J mice. J Nutr Biochem 2015; 26:57-63. [DOI: 10.1016/j.jnutbio.2014.09.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 08/14/2014] [Accepted: 09/10/2014] [Indexed: 11/21/2022]
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10
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Beppu F, Konno K, Kawamatsu T, Nagai T, Yoshinaga K, Mizobe H, Kojima K, Watanabe H, Gotoh N. Comparison of catabolic rates of
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C‐labeled palmitic acid bound to the alpha and beta positions of triacylglycerol using CO
2
expired from mice. EUR J LIPID SCI TECH 2014. [DOI: 10.1002/ejlt.201400326] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Fumiaki Beppu
- Department of Food Science and TechnologyTokyo University of Marine Science and Technology4‐5‐7 KonanMinato‐kuTokyo108‐8477Japan
| | - Kaoru Konno
- Department of Food Science and TechnologyTokyo University of Marine Science and Technology4‐5‐7 KonanMinato‐kuTokyo108‐8477Japan
| | - Takashi Kawamatsu
- Department of Food Science and TechnologyTokyo University of Marine Science and Technology4‐5‐7 KonanMinato‐kuTokyo108‐8477Japan
| | - Toshiharu Nagai
- Tsukishima Foods Industry Co. Ltd.3‐17‐9Higashi KasaiEdogawa‐kuTokyo134‐8520Japan
| | - Kazuaki Yoshinaga
- Tsukishima Foods Industry Co. Ltd.3‐17‐9Higashi KasaiEdogawa‐kuTokyo134‐8520Japan
| | - Hoyo Mizobe
- Tsukishima Foods Industry Co. Ltd.3‐17‐9Higashi KasaiEdogawa‐kuTokyo134‐8520Japan
| | - Koichi Kojima
- Tsukishima Foods Industry Co. Ltd.3‐17‐9Higashi KasaiEdogawa‐kuTokyo134‐8520Japan
| | - Hiroyuki Watanabe
- Department of Health ScienceUniversity of Kochi2751‐1 IkeKochi‐shiKochi781‐0111Japan
| | - Naohiro Gotoh
- Department of Food Science and TechnologyTokyo University of Marine Science and Technology4‐5‐7 KonanMinato‐kuTokyo108‐8477Japan
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11
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Dubey P, Jayasooriya AP, Cheema SK. Diets Enriched in Fish-Oil or Seal-Oil have Distinct Effects on Lipid Levels and Peroxidation in BioF1B Hamsters. Nutr Metab Insights 2011; 4:7-17. [PMID: 23946657 PMCID: PMC3738469 DOI: 10.4137/nmi.s6728] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Aim: Fish-oil omega-3 polyunsaturated fatty acids (n-3 PUFAs) are mostly esterified to the sn-2 position of triglycerides, while in seal-oil triglycerides, these are mostly esterified to the sn-1 and -3 positions. We investigated whether fish-oil and seal-oil feeding has a different effect on the regulation of lipid metabolism and oxidative stress in BioF1B hamsters. Methods: BioF1B hamsters were fed high fat diets rich in fish-oil or seal-oil for 4 weeks, and fasted for 14 hours prior to blood and tissue collection. Results: Plasma and hepatic lipids and lipid peroxidation levels were significantly lower in seal-oil-fed hamsters as compared to those fed fish-oil. There was a selective hindrance of clearance of lipids in fish-oil-fed hamsters as reflected by higher levels of plasma apoB48. Conclusion: Differences in the fatty acid composition and positional distribution of n-3 PUFAs in triglycerides of fish-oil and seal-oil are suggested to trigger metabolic differences.
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Affiliation(s)
- Pratibha Dubey
- Department of Biochemistry, Memorial University, St. John's, NL, A1B 3X9, Canada
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12
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Sala-Vila A, Castellote AI, López-Sabater MC. The intramolecular position of docosahexaenoic acid in the triacylglycerol sources used for pediatric nutrition has a minimal effect on its metabolic use. Nutr Res 2009; 28:131-6. [PMID: 19083399 DOI: 10.1016/j.nutres.2007.11.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2007] [Revised: 11/19/2007] [Accepted: 11/19/2007] [Indexed: 11/29/2022]
Abstract
Docosahexaenoic acid (DHA) plays an important role in normal development of the brain and retina in the human. In utero, DHA is incorporated in the fetus, and its accretion continues throughout early postnatal life. Although human breast milk contains this fatty acid, several organizations recommend supplementing infant formulas with DHA for infants and premature infants. Traditionally, certain types of fish oil have been used for fortifying some infant formulas, but with the decline in world fisheries, the search for alternative sources of DHA continues. Among the viable ingredient sources of DHA is oil derived from single-cell organisms (marine microorganisms); however, these oil sources display different positional specificity of DHA in the glycerol lipids compared with that found in human breast milk lipids. In the latter, the DHA is mainly esterified in the central position of the glycerol backbone. Because of these differences in human milk and oils derived from single-cell organisms, recent research in biotechnology has focused on developing new structured triacylglycerols with an intramolecular structure resembling that found in human milk lipids. This research is justified by the potential differences in metabolism of DHA based on the hypothetical bioavailability and benefits in DHA found in human milk lipids. Presented herein is a review of the published research on the metabolism of DHA from different triacylglycerol sources including in vitro studies and animal studies. Despite small differences observed in digestion, the current data reveal a minimal effect on the parameters of development studied for the intramolecular position in which DHA is esterified.
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Affiliation(s)
- Aleix Sala-Vila
- Department of Nutrition and Food Science, Faculty of Pharmacy, University of Barcelona, Avda Joan XXIII s/n, E-08028 Barcelona, Spain
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13
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Pacetti D, Boselli E, Hulan HW, Frega NG. High performance liquid chromatography-tandem mass spectrometry of phospholipid molecular species in eggs from hens fed diets enriched in seal blubber oil. J Chromatogr A 2005; 1097:66-73. [PMID: 16298186 DOI: 10.1016/j.chroma.2005.08.016] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2005] [Revised: 06/22/2005] [Accepted: 08/05/2005] [Indexed: 10/25/2022]
Abstract
The total lipid fraction of eggs from hens fed diets enriched in seal blubber oil (1.25-5.0% SBO) was directly analysed with normal-phase high performance liquid chromatography coupled on-line with electrospray ionization ion-trap tandem mass spectrometry (HPLC-ESI-MS-MS) for the identification of the molecular species of phospholipids (PLs). The species of phosphatidylethanolamine (PE) and phosphatidylinositol (PI) were all detected as the [M-H](-) ions. The phosphatidylcholine (PC), sphingomyelin (Sph) and lysophosphatidylcholine (LPC) classes, were detected as formate adducts [M+HCOO](-). Tandem MS of PE and PI showed the loss of the carboxylate anions, and, for PI, also the loss of water and inositol. Product ion spectrum of PC, LPC and Sph contained only the [M-CH(3)](-) ion fragment. Feeding different levels of SBO for 5 weeks resulted in a significant increase of PE, PC and PI molecular species carrying eicosapentaenoic acid (C(20:5 omega3), EPA), docosapentaenoic acid (C(22:5 omega3), DPA) and docosahexaenoic acid (C(22:6 omega3), DHA), but not Sph nor LPC. The highest increase of the omega3/omega6 ratio occurred for PE and PC. On the contrary, PI was less affected by the increase of SBO in the diet.
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Affiliation(s)
- Deborah Pacetti
- Dipartimento di Scienze degli Alimenti, Università Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona, Italy
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Mu H, Porsgaard T. The metabolism of structured triacylglycerols. Prog Lipid Res 2005; 44:430-48. [PMID: 16269186 DOI: 10.1016/j.plipres.2005.09.002] [Citation(s) in RCA: 167] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2005] [Accepted: 09/14/2005] [Indexed: 11/28/2022]
Abstract
The triacylglycerol (TAG) structure in addition to the overall fatty acid profile is of importance when considering the nutritional effect of a dietary fat. This review aims at summarizing our current knowledge of the digestion, absorption, uptake, and transport of structured TAGs, with particular emphasis on the following aspects: gastric emptying, specificity of pancreatic lipase, lymphatic transport and clearance of chylomicrons, effects of lipid structure on tissue lipid compositions and the fecal loss of fats. So an overview will be provided for how the structure and fatty acid composition of TAGs affect their absorption and the distribution of the fatty acids in the body following digestion and absorption.
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Affiliation(s)
- Huiling Mu
- BioCentrum-DTU, Biochemistry and Nutrition Group, Center for Advanced Food Studies, The Technical University of Denmark, Building 224, DK-2800 Lyngby, Denmark.
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15
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Wijesundera C. Synthesis of regioisomerically pure triacylglycerols containingn-3 very long-chain polyunsaturated fatty acids. EUR J LIPID SCI TECH 2005. [DOI: 10.1002/ejlt.200500238] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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16
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Linderborg (née Yli-Jokipii) KM, Kallio HPT. Triacylglycerol Fatty Acid Positional Distribution and Postprandial Lipid Metabolism. FOOD REVIEWS INTERNATIONAL 2005. [DOI: 10.1080/fri-200061623] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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17
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Porsgaard T, Kánský J, Mason S, Mu H. Size and number of lymph particles measured by a particle sizer during absorption of structured oils in rats. Lipids 2005; 40:273-9. [PMID: 15957253 DOI: 10.1007/s11745-005-1382-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Chylomicrons transport absorbed fat from the intestine to the circulation. During dietary fat absorption, the chylomicrons become larger in diameter, and in some studies an increase in chylomicron number has been observed as well. In the present study, we compared particle size and number in rat lymph following administration of four different oils. We administered fish oil, medium-chain TAG (MCT), and two structured oils differing in intramolecular structure, with either medium-chain FA in the outer positions of the TAG and long-chain n-3 PUFA in the sn-2 position (MLM oil) or with the reverse structure (LML oil), to lymph-cannulated rats and collected lymph in fractions for the following 8 h. Chylomicron size was measured by a particle size analyzer immediately after collection, and from these data the number of chylomicrons present was estimated. The number of particles in lymph increased during the absorption of oils containing long-chain PUFA (MLM, LML, and fish oil), whereas it was not affected by administration of MCT. The FA from MCT were probably absorbed via the portal vein; therefore, only a small number of particles were measured in lymph. When comparing the two structured oils, we observed a tendency toward a higher number of particles after LML administration, although the difference was not statistically significant. The highest number of particles after administration of all oils was observed in the size intervals 53-80 and 80-121 nm and probably represented small chylomicrons. Thus, the FA composition influenced the number of particles in lymph during absorption, whereas TAG structure had only a minor influence.
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Affiliation(s)
- Trine Porsgaard
- BioCentrum-DTU and Center for Advanced Food Studies (LMC), Technical University of Denmark, 2800 Lyngby, Denmark.
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18
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Ikeda I, Kumamaru J, Nakatani N, Sakono M, Murota I, Imaizumi K. Reduced hepatic triglyceride secretion in rats fed docosahexaenoic acid-rich fish oil suppresses postprandial hypertriglyceridemia. J Nutr 2001; 131:1159-64. [PMID: 11285319 DOI: 10.1093/jn/131.4.1159] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
To evaluate the mechanisms of suppression of postprandial hypertriglyceridemia by fish oil rich in docosahexaenoic acid, the effect on the intestinal absorption of triglyceride, activities of lipoprotein lipase (LPL) and hepatic triglyceride lipase (HTGL) and metabolism of chylomicrons (CM) and CM remnants were compared with that of safflower oil in Sprague-Dawley rats in a series of studies. The feeding of fish oil for 3 wk suppressed postprandial hypertriglyceridemia (study 1). Dietary fish oil did not alter the rate of lymphatic absorption of triglyceride (study 2). The activities of LPL and HTGL were measured at 5 h after the beginning of feeding, when serum triglyceride concentrations were highest in both dietary groups. The activities of LPL in adipose tissue and heart were greater (P < 0.05) and those of HTGL were lower (P < 0.05) in the rats fed fish oil (study 3). In contrast, there were no differences in the activities of LPL and HTGL in postheparin plasma between the fish and safflower oil groups (study 4). The clearance rates of CM and CM remnants were measured by injecting intravenously CM collected from rats fed safflower or fish oils with [14C]triolein and [3H]cholesterol (study 5). Dietary oil did not influence the half-lives of CM or CM remnants. The secretion of triglyceride from the liver of rats injected with Triton WR-1339 was lower (P < 0.05) in the rats fed docosahexaenoic acid, a major component of fish oil, than those fed linoleic acid, a major component of safflower oil (study 6). These observations strongly support the hypothesis that in rats, the principal cause of the suppression of postprandial hypertriglyceridemia by fish oil is the depression of triglyceride secretion from the liver.
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Affiliation(s)
- I Ikeda
- Laboratory of Nutrition Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School Kyushu University, Fukuoka, 812-8581 Japan.
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Porsgaard T, Høy CE. Lymphatic transport in rats of several dietary fats differing in fatty acid profile and triacylglycerol structure. J Nutr 2000; 130:1619-24. [PMID: 10827219 DOI: 10.1093/jn/130.6.1619] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We examined in rats the intestinal absorption of nine very different dietary fats (two rapeseed oils, corn, olive, palm and menhaden oil, butter, cocoa butter and lard) to investigate the influence of fatty acid profile and triacylglycerol structure on absorption. Absorption was followed for 24 h after administration of similar amounts of fats, and the accumulated lymphatic transport and amount of triacylglycerols found in lymph in response to the administered fats were calculated, revealing major differences. The transport of olive and low alpha-linolenic rapeseed oil was significantly higher than that of the other fats (P < 0.05), except corn oil. The lymphatic transport of the other fats followed a slower course, with cocoa butter and menhaden oil having the lowest amounts transported. The amount of triacylglycerols found in lymph in response to the administered fats at 8 h ranged from 27.5% of the administered dose for cocoa butter to 72.1% for olive oil. The value for cocoa butter was significantly lower than that for most other fats. At 24 h, the values ranged from 66.5% for cocoa butter to 121.2% for olive oil. The high value for olive oil suggested transport of endogenous as well as exogenous fatty acids. The low value observed after cocoa butter resulted from decreased lipolysis and possibly also low absorption of triacylglycerols with high levels of long-chain saturated fatty acids in the sn-1/3 position. Furthermore, a low value was observed after menhaden oil administration, suggesting decreased absorption of fats containing (n-3) long-chain polyunsaturated fatty acids. Overall, these results demonstrate the influence of the fatty acid composition and triacylglycerol structure on the lymphatic absorption of dietary fat.
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Affiliation(s)
- T Porsgaard
- Department of Biochemistry and Nutrition, The Technical University of Denmark, DK-2800 Lyngby, Denmark
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Mu H, Xu X, Høy CE. Production of specific-structured triacylglycerols by lipase-catalyzed interesterification in a laboratory-scale continuous reactor. J AM OIL CHEM SOC 1998. [DOI: 10.1007/s11746-998-0310-6] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- H. Mu
- ; Department of Biochemistry and Nutrition; Technical University of Denmark; Building 224 DK-2800 Lyngby Denmark
| | - X. Xu
- ; Department of Biotechnology, Center for Advanced Food Research; Technical University of Denmark; DK-2800 Lyngby Denmark
| | - C. -E. Høy
- ; Department of Biochemistry and Nutrition; Technical University of Denmark; Building 224 DK-2800 Lyngby Denmark
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Production of specific-structured triacylglycerols by lipase-catalyzed interesterification in a laboratory-scale continuous reactor. J AM OIL CHEM SOC 1998. [DOI: 10.1007/s11746-998-0133-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Ikeda I, Yoshida H, Tomooka M, Yosef A, Imaizumi K, Tsuji H, Seto A. Effects of long-term feeding of marine oils with different positional distribution of eicosapentaenoic and docosahexaenoic acids on lipid metabolism, eicosanoid production, and platelet aggregation in hypercholesterolemic rats. Lipids 1998; 33:897-904. [PMID: 9778137 DOI: 10.1007/s11745-998-0286-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were distributed mainly in the sn-1,3 positions of seal oil triglyceride and in the sn-2 position of squid oil triglyceride. Seal oil-rich or squid oil-rich fats having constant saturated/monounsaturated/polyunsaturated fatty acid (PUFA) and n-6/n-3 PUFA ratios were fed to exogenously hypercholesterolemic rats for 1 60 d. The control fat contained linoleic acid as the sole PUFA. Before starting the experimental diets, rats were orally treated with high doses of vitamin D for 4 d to accelerate atherogenesis. The percentage of arachidonic acid in phosphatidylcholine and phosphatidylethanolamine of liver, platelets, and aorta was lower in the marine oil groups than in the control group, seal oil being more effective than squid oil. Maximal platelet aggregation induced by collagen was significantly lower in both marine oil groups. Platelet thromboxane (TX) A2 production induced by collagen or thrombin was markedly reduced by feeding seal or squid oils, the reduction being more pronounced in the seal oil than in the squid oil group. Aortic prostacyclin (PGI2) production was the same among the three groups. The ratio of the productions of aortic PGI2 and platelet TXA2 was significantly higher in the seal oil than in the control group. Although there was no difference in intimal thickness among the three groups, the aortic cholesterol content was significantly lower in the marine oil groups than in the control group. These results showed that the main effects in rats of the different intramolecular distributions of EPA and DHA in dietary fats were on arachidonic acid content in tissue phospholipids and on platelet TXA2 production.
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Affiliation(s)
- I Ikeda
- Laboratory of Nutrition Chemistry, Faculty of Agriculture, Kyushu University, Fukuoka, Japan.
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Smith SB, Yang A, Larsen TW, Tume RK. Positional analysis of triacylglycerols from bovine adipose tissue lipids varying in degree of unsaturation. Lipids 1998; 33:197-207. [PMID: 9507242 DOI: 10.1007/s11745-998-0196-8] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The objective of this study was to demonstrate that changing the fatty acid composition of bovine adipose tissue concurrently changed (i) proportions of triacylglycerol species, (ii) fatty acid composition of triacylglycerol species, and (iii) positional distribution of the component fatty acids of the triacylglycerol species. To achieve this, we took advantage of adipose tissue lipids, from cattle fed in Australia and Japan, that varied widely in fatty acid composition and melting points. Treatment groups produced in Australia were cattle fed: a cornbased diet (MUFA1); a grain-based diet containing whole cottonseed (SFA); a grain-based diet containing protected cottonseed oil (PUFA); and a grain-based diet that resulted in high contents of trans fatty acids (TFA). Treatment groups produced in Japan (MUFA2 and MUFA3) were diets of unknown composition fed for over 300 d. The MUFA1, MUFA2, and MUFA3 samples all were rich in monounsaturated fatty acids, varying only in the proportions of the individual monounsaturates. The SFA, PUFA, and TFA samples had relatively high concentrations of stearic acid (18:0), PUFA, and TFA, respectively. Slip points (indicative of melting points) were 45.1, 41.5, 38.5, 30.7, 28.4, and 22.8 degrees C, for the SFA, TFA, PUFA, MUFA1, MUFA2, and MUFA3 groups, respectively (P < 0.05). Triacylglycerols were separated by high-performance liquid chromatography on a silver nitrate-impregnated column into sn-1,2,3-saturated fatty acid triacylglycerol (SSS); [triacylglycerols containing two saturated acids and one trans-monounsaturated fatty acid (SMMt sn-positions unknown)]; sn-1-saturated, 2-monounsaturated, 3-saturated triacylglycerol (SMS); sn-1-saturated, 2-monounsaturated 3-trans-monounsaturated triacylglycerol (SMMt); sn-1-saturated, 2,3-monounsaturated fatty acid triacylglycerol (SMM); sn-1-saturated, 2-polyunsaturated, 3-trans-monounsaturated triacylglycerol; sn-1,2,3-monounsaturated fatty acid triacylglycerol (MMM); and sn-1-saturated, 2-polyunsaturated, 3-monounsaturated triacylglycerol. Fatty acid methyl esters of each triacylglycerol species also were determined, and further analysis indicated sn-2, and sn-1/3 positions. As the percentage oleic acid increased in the total lipid extract, the proportions of SMM and MMM increased (e.g., from 31.4 and 2.4% in the SFA group to 55.4 and 17.8% in the MUFA3 group). The elevated 18:0 in the SFA group (26%) was reflected in increased percentages of SSS and SSM, and caused an increase in the proportion of 18:0 in all triacylglycerol species relative to the other treatment groups. The percentage of 18:0 in the sn-1/3 positions was elevated markedly in the SMS fraction of the SFA group (to 44%); this would account for the high melting point of the fat of these animals. We conclude that long-term feeding of cattle is sufficient to produce significant alterations in fatty acid composition in bovine adipose tissue. Alterations in the fatty acid composition of bovine adipose tissue changed both the distribution and the composition of the triacylglycerol species, which, in turn, accounted for marked differences in melting points among treatment groups.
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Affiliation(s)
- S B Smith
- CSIRO, Division of Food Science and Technology, Brisbane Laboratory, Tingalpa, Queensland, Australia.
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Ikeda I, Yoshida H, Imaizumi K. Effects of triolein or oleic acid on lymphatic recovery of docosahexaenoic acid given as ethyl ester and their intramolecular distribution in lymph triglyceride of rats. Lipids 1997; 32:949-52. [PMID: 9307935 DOI: 10.1007/s11745-997-0122-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Effects of oleic acid or triolein on lymphatic recovery of docosahexaenoic acid (DHA) given as an ethyl ester were examined in rats with cannulated thoracic ducts. Lymphatic recovery of ethyl DHA given with oleic acid or triolein was significantly higher than in rats given ethyl DHA alone. DHA distributed almost exclusively at the 1- and 3-position of triglyceride in lymph collected at 0-3 h after the administration, when it was given with oleic acid or triolein. A small part of DHA distributed at the 2-position when ethyl DHA was the sole fatty acid given. Oleic acid given as free acid or triolein with ethyl DHA was a major fatty acid at the 2-position. Intramolecular distribution of DHA and oleic acid in lymph triglyceride was similar when ethyl DHA was given with oleic acid or triolein.
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Affiliation(s)
- I Ikeda
- Laboratory of Nutrition Chemistry, Faculty of Agriculture, Kyushu University, Fukuoka, Japan.
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Christensen MM, Høy CE. Early dietary intervention with structured triacylglycerols containing docosahexaenoic acid. Effect on brain, liver, and adipose tissue lipids. Lipids 1997; 32:185-91. [PMID: 9075209 DOI: 10.1007/s11745-997-0023-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Newborn rats were fed liquid diets containing 7 wt% fat in which 3.8% of the total fatty acids were 22:6n-3. The fats were either a specific structured oil with 22:6n-3 mostly located in the sn-2 position or a randomized oil with 22:6n-3 equally distributed in the triacylglycerol (TAG) molecules. The oils were manufactured by interesterification of fish oil TAG with free fatty acids from butterfat. The pups were tube-fed three times a day and stayed with their dams during the night. After 14 d they were fed solid diets containing the same oils for the next 7 d. A reference group stayed with the dams and received ordinary rat chow at weaning. In general no significant differences between the two dietary treatments were observed in the tissues examined except for adipose tissue. The levels of 22:6n-3 were significantly increased in brain phosphatidylcholines (PC) and phosphatidylserines (PS) of both experimental groups compared with the reference group after three weeks, whereas no differences were found in brain phosphatidylethanolamines (PE) and phosphatidylinositols (PI). In all groups and all phospholipids examined, the levels of 20:4n-6 generally decreased from 1 to 3 wk and were significantly lower in the experimental groups compared with the reference group at 3 wk except for PI. In liver, PC and PE 22:6n-3 remained constant in the experimental groups but decreased significantly in the reference group, whereas in liver PS 22:6n-3 increased in all groups, but reached significantly higher levels in the experimental groups than in the reference group. In adipose tissue, 22:6n-3 increased in the experimental groups during the study period, but decreased in the reference group, suggesting that a surplus of dietary 22:6n-3 was stored.
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Affiliation(s)
- M M Christensen
- Department of Biochemistry and Nutrition, Technical University of Denmark, Lyngby, Denmark
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Kubow S. The influence of positional distribution of fatty acids in native, interesterified and structure-specific lipids on lipoprotein metabolism and atherogenesis. J Nutr Biochem 1996. [DOI: 10.1016/s0955-2863(96)00106-4] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Jensen MM, Skarsfeldt T, Høy CE. Correlation between level of (n - 3) polyunsaturated fatty acids in brain phospholipids and learning ability in rats. A multiple generation study. BIOCHIMICA ET BIOPHYSICA ACTA 1996; 1300:203-9. [PMID: 8679685 DOI: 10.1016/0005-2760(96)00007-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The effects of dietary n - 3 polyunsaturated fatty acids (PUFAs) on major brain phospholipids were examined in the rat throughout four generations. Dietary fats were: a seal oil (22:6(n - 3) located mainly in the sn-1/3-position of the TG); a fish oil (22:6(n - 3) located mainly in the sn-2 position of the TG); or a vegetable oil containing 18:3(n - 3). The effect of the TG structure of the dietary fat and chain length of n - 3 PUFA on assimilation in the brain was compared with chow fed rats. The rats fed marine fats had significantly higher levels of long-chain n - 3 PUFAs in brain PE and PS, compared to the vegetable oil and chow fed rats, but no effects of TG structure of dietary fat were observed. Dietary 18:3(n - 3) raised the amount of 22:6(n - 3) compared to the control group, but not to the levels of the marine groups that received preformed 22:6(n - 3). Fish oil fed rats had higher levels of 20:5(n - 3) and 22:5(n - 3) compared with the seal oil fed rats, whereas 22:6(n - 3) were similar. Only minor changes in PI, PIP, and PIP2 were found. The fourth generation was tested for spatial learning ability in a Morris water maze. The experimental groups had similar learning abilities, which were increased compared to the control group.
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Affiliation(s)
- M M Jensen
- Department of Biochemistry and Nutrition, Technical University of Denmark, Lyngby, Denmark
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Christensen MS, Høy CE. Effects of dietary triacylglycerol structure on triacylglycerols of resultant chylomicrons from fish oil- and seal oil-fed rats. Lipids 1996; 31:341-4. [PMID: 8900465 DOI: 10.1007/bf02529882] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We investigated the influence of the intramolecular fatty acid distribution of dietary triacyl-sn-glycerols (TAG) rich in n-3 polyunsaturated fatty acids (PUFA) on the structure of chylomicron TAG. Fish oil and seal oil, comparable in fatty acid compositions but with different contents of major n-3 PUFA esterified at the sn-2 position (20:5n-3, 46.6%, and 5.3%; 22:6n-3, 75.5%, and 3.8%, respectively), were fed to rats. Mesenteric lymph was collected and the chylomicrons were isolated by ultracentrifugation. The fatty acid composition of chylomicrons largely reflected the fatty acid composition of the oils administered. The intramolecular fatty acid distributions of the TAG fed were reflected in the chylomicron TAG as the fraction of the total contents observed in the sn-2 position of 20:5n-3 were 23.6 and 13.3%, and of 22:6n-3 were 30.6 and 5.4% for resultant chylomicrons following fish oil and seal oil administration, respectively. Thus, after seal oil administration, significant higher load of n-3 PUFA was esterified in the sn-1,3 positions of chylomicron TAG compared with fish oil administration (P < 0.05).
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Affiliation(s)
- M S Christensen
- Department of Biochemistry and Nutrition and Center for Food Research, Technical University of Denmark, Lyngby
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Jensen MM, Sørensen H, Høy CE. Influence of triacylglycerol structure and fatty acid profile of dietary fats on milk triacylglycerols in the rat. A two-generation study. Lipids 1996; 31:187-92. [PMID: 8835407 DOI: 10.1007/bf02522619] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We investigated the influence of dietary fatty acid profile and triacylglycerol structure on the fatty acid profile and triacylglycerol structure of milk lipids in two generations of rats. Three groups of rats received diets containing 20% fat of which approximately 20% was n-3 fatty acids located in different positions of the triacylglycerol: a fish oil-based diet [docosahexaenoic acid (22:6n-3) predominantly in the sn-2 position], a seal oil-based diet (22:6n-3) predominantly in the sn-1/sn-3 position, or a plant oil-based diet [alpha-linolenic acid (18:3n-3) distributed evenly between the three positions]. This design allowed us to investigate (i) the effect of the triacylglycerol structure of the dietary fat; (ii) the effect of receiving the n-3 fatty acids as long-chain derivatives or as the precursor, 18:3n-3; and (ii) the long-term effects over two generations. The fatty acid profiles of the milk lipids largely reflected the diets, but in the second generation, the level of medium-chain fatty acids was higher (P < 0.05) in the milk from rats fed the fish oil diet (24%) compared with the other dietary groups (15 and 18%). This suggests an increased endogenous synthesis of fatty acids in the mammary glands of the fish oil-fed rats. The levels of long-chain n-3 fatty acids in milk were higher (P < 0.05) in rats fed marine oils (8-12%) compared with rats fed vegetable oil (1%) in both generations. The level of long-chain n-3 fatty acids was significantly higher in the milk from the fish oil-fed rats (12.3%) compared to the seal- oil fed rats (8.0%) in the first generation, but not in the second generation (8.9 vs. 9.1%). The general structure of milk triacylglycerols was maintained in the three experimental groups with 16:0 acylated in the sn-2 position and 18:1 in the sn-1/sn-3 positions. The triacylglycerol structure of mammalian milk appears to be conserved even during extreme dietary manipulation over two generations and an extensive enrichment with long-chain n-3 polyunsaturated fatty acids requires their presence in the diet.
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Affiliation(s)
- M M Jensen
- Department of Biochemistry and Nutrition, Technical University of Denmark
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