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1.
Helvi M. Vidgren Jyrki J. Ågren Ursula Schwab Tiina Rissanen Osmo Hänninen Matti I. J. Uusitupa 《Lipids》1997,32(7):697-705
The effects of n-3 fatty acid supplementation in the form of fresh fish, fish oil, and docosahexaenoic acid (DHA) oil on the
fatty acid composition of plasma lipid fractions, and platelets and erythrocyte membranes of young healthy male students were
examined. Altogether 59 subjects (aged 19–32 yr, body mass index 16.8–31.3 kg/m2) were randomized into the following diet groups: (i) control group; (ii) fish diet group eating fish meals five times per
week [0.38±0.04 g eicosapentaenoic acid (EPA) and 0.67±0.09 g DHA per day]; (iii) DHA oil group taking algae-derived DHA oil
capsules (1.68 g/d DHA oil group taking algae-derived DHA oil capsules (1.68 g/d DHA in triglyceride form); and (iv) fish
oil group (1.33 g EPA and 0.95 g DHA/d as free fatty acids) for 14 wk. The fatty acid composition of plasma lipids, platelets,
and erythrocyte membranes was analyzed by gas chromatography. The subjects kept 4-d food records four times during the study
to estimate the intake of nutrients. In the fish diet, in DHA oil, and in fish oil groups, the amounts of n-3 fatty acids
increased and those of n-6 fatty acids decreased significantly in plasma lipid fractions and in platelets and erythrocyte
membranes. A positive relationship was shown between the total n-3 polyunsaturated fatty acids (PUFA) and EPA and DHA intake
and the increase in total n-3 PUFA and EPA and DHA in all lipid fractions analyzed. DHA was preferentially incorporated into
phospholipid (PL) and triglyceride (TG) and there was very little uptake in cholesterol ester (CE), while EPA was preferentially
incorporated into PL and CE. The proportion of EPA in plasma lipids and platelets and erythrocyte membranes increased also
by DHA supplementation, and the proportion of linoleic acid increased in platelets and erythrocyte membranes in the DHA oil
group as well. These results suggest retroconversion of DHA to EPA and that DHA also interferes with linoleic acid metabolism. 相似文献
2.
The aim of the present study was to investigate whether eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) was responsible
for the triglyceride-lowering effect of fish oil. In rats fed a single dose of EPA as ethyl ester (EPA-EE), the plasma concentration
of triglycerides was decreased at 8 h after acute administration. This was accompanied by an increased hepatic fatty acid
oxidation and mitochondrial 2,4-dienoyl-CoA reductase activity. The steady-state level of 2,4-dienoyl-CoA reductase mRNA increased
in parallel with the enzyme activity. An increased hepatic long-chain acyl-CoA content, but a reduced amount of hepatic malonyl-CoA,
was obtained at 8 h after acute EPA-EE treatment. On EPA-EE supplementation, both EPA (20:5n-3) and docosapentaenoic acid
(DPA, 22:5n-3) increased in the liver, whereas the hepatic DHA (22:6n-3) concentration was unchanged. On DHA-EE supplementation
retroconversion to EPA occurred. No statistically significant differences were found, however, for mitochondrial enzyme activities,
malonyl-CoA, long-chain acyl-CoA, plasma lipid levels, and the amount of cellular fatty acids between DHA-EE treated rats
and their controls at any time point studied. In cultured rat hepatocytes, the oxidation of [1-14C]palmitic acid was reduced by DHA, whereas it was stimulated by EPA. In thein vivo studies, the activities of phosphatidate phosphohydrolase and acetyl-CoA carboxylase were unaffected after acute EPA-EE and
DHA-EE administration, but the fatty acyl-CoA oxidase, the rate-limiting enzyme in peroxisomal fatty acid oxidation, was increased
after feeding these n-3 fatty acids. The hypocholesterolemic properties of EPA-EE may be due to decreased 3-hydroxy-3-methylglutaryl-CoA
reductase activity. Furthermore, replacement of the ordinary fatty acids, i.e., the monoenes (16:1n-7, 18:1n-7, and 18:1n-9)
with EPA and some conversion to DPA concomitant with increased fatty acid oxidation is probably the mechanism leading to changed
fatty acid composition. In contrast, DHA does not stimulate fatty acid oxidation and, consequently, no such displacement mechanism
operates. In conclusion, we have obtained evidence that EPA, and not DHA, is the fatty acid primarily responsible for the
triglyceride-lowering effect of fish oil in rats. 相似文献
3.
Polyunsaturated fatty acids exert antiarrhythmic actions as free acids rather than in phospholipids 总被引:5,自引:3,他引:5
Previous studies have shown that exogenous free n-3 polyunsaturated fatty acids (PUFA) can prevent tachyarrhythmias caused
by specific agents in isolated cardiac myocytes. However, the question as to whether incorporation of the n-3 PUFA into membrane
phospholipids has the same immediate protective effects remained to be answered. To answer this question, we increased the
content of n-3 PUFA in the phospholipids of cultured neonatal rat myocytes by growing them 2–3 d in a culture to which eicosapentaenoic
acid (EPA) or docosahexaenoic acid (DHA) in 15 μM concentration was added. Analysis of the fatty acid composition of membrane
phospholipids revealed a significantly higher level of EPA and DHA (from 0.2 to 7.6% and from 1.2 to 6.5%) in cells supplemented
with EPA or DHA, respectively. The responses of the myocytes grown in normal media or in media enriched with the PUFA to arrhythmogenic
agents were examined after free fatty acids were removed from the medium and the cells. The arrhythmogenic agents used were
the β-adrenergic agonist isoproterenol or an elevated extracellular concentration of calcium. The results showed that there
was no significant difference in the induction of tachyarrhythmias by isoproterenol or by elevated [Ca2+]o in cells grown in media enriched with PUFA, as compared with cells grown in normal media in the absence of the free PUFA.
Under the conditions of this study, only the unesterified PUFA were able to protect the cardiomyocytes against induced arrhythmias.
There was no antiarrhythmic effect due to an increased fraction of EPA or DHA in membrane phospholipids. 相似文献
4.
Gabriella Calviello Paola Palozza Piergiorgio Franceschelli Gianna Maria Bartoli 《Lipids》1997,32(10):1075-1083
In view of the promising future for use of n-3 polyunsaturated fatty acids (PUFA) in the prevention of cancer and cardiovascular
diseases, it is necessary to ensure that their consumption does not result in detrimental oxidative effects. The aim of the
present work was to test a hypothesis that low doses of eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) do not induce
harmful modifications of oxidative cell metabolism, as modifications of membrane fatty acid composition occur. Wistar rats
received by gavage oleic acid, EPA, or DHA (360 mg/kg body weight/day) for a period of 1 or 4 wk. Fatty acid composition and
α-tocopherol content were determined for plasma, red blood cell (RBC) membranes, and liver, kidney, lung, and heart microsomal
membranes. Susceptibility to oxidative stress induced by tert-butylhydroperoxide was measured in RBC. EPA treatment increased EPA and docosapentaenoic acid (DPA) content in plasma and
in all the membranes studied. DHA treatment mainly increased DHA content. Both treatments decreased arachidonic acid content
and n-6/n-3 PUFA ratio in the membranes, without modifying the Unsaturation Index. No changes in tissue α-tocopherol content
and in RBC susceptibility to oxidative stress were induced by either EPA or DHA treatment. The data suggest that EPA and DHA
treatments can substantially modify membrane fatty acids, with-out increasing susceptibility to oxidative stress, when administered
at low doses. This opens the possibility for use of low doses of n-3 PUFA for chemoprevention without risk of detrimental
secondary effects. 相似文献
5.
Polyunsaturated fatty acids (PUFA) such as γ-linolenic acid (GLA, 18:3n-6), eicosapentaenoic acid (EPA, 20: 5n-3), and docosahexaenoic
acid (DHA, 22:6n-3) have been shown to be cytotoxic to tumor cells. The objective of this work was to study the effect of
PUFA on the radiation response of a 36B10 rat astrocytoma cell line. Supplementation of the astrocytoma cells with 15–45 μM
GLA, EPA, or DHA produced marked changes in the fatty acid profiles of their phospholipids and neutral lipids. The methylene
bridge index of these lipids increased significantly. These PUFA also exerted cytotoxic effects, as determined using the clonogenic
cell survival assay. While GLA and DHA produced a moderate cell-killing effect, EPA was extremely cytotoxic, especially at
a concentration of 45 μM. The monounsaturated oleic acid (OA, 18:1n-9) did not affect cell survival. Further, all three PUFA,
and particularly GLA, increased the radiation-induced cell kill; OA did not enhance the effect of radiation. α-Tocopherol
acetate blocked the enhanced radiation sensitivity of GLA- and DHA-supplemented cells. In conclusion, GLA, EPA, and DHA supplementation
prior to, during, and after irradiation can enhance the radiation-induced cytotoxicity of rat astrocytoma cells. GLA and DHA
supplementation post-irradiation also enhanced the radiation response of the 36B10 cells. Because GLA maximally increases
the radioresponsiveness of a rat astrocytoma, this PUFA might prove useful in increasing the therapeutic efficacy of radiation
in the treatment of certain gliomas. 相似文献
6.
Shu Cheng Liu De Tao Li Peng Zhi Hong Chao Hua Zhang Hong Wu Ji Jia Long Gao Li Zhang 《Journal of the American Oil Chemists' Society》2009,86(12):1155-1161
Marine fishes are rich in n-3 polyunsaturated fatty acids (PUFA), especially eicosapentaenoic acid (EPA) and docosahexaenoic
acid (DHA), which are extremely important for human health. The objective of our work was to determine the content and composition
of lipids and fatty acids in the different tissues of cobia from China and to evaluate their nutritional value. The results
showed that cobia from China was rich in lipids; the neutral lipid content was above 82%; the content of cholesterol and phospholipid
was low. Eighteen fatty acids were identified. Myristic (C14:0), palmitic (C16:0), and stearic acids (C18:0) were the main
saturated acids; palmitoleic (C16:1n-7) and oleic acid (C18:1n-9) were the main monounsaturated fatty acids. EPA and DHA were
the main PUFA; n-3 and n-6 PUFA were present as 12–18% and 2.6–3.2% of the total fatty acids, respectively. The n-6/n-3 ratio
was in the range from 0.18 to 0.22, which was far lower than that (5:1) recommended by WHO/FAO. Therefore, cobia lipids from
China have a high nutritional value. 相似文献
7.
Mechanisms for the antiarrhythmic effect of n−3 polyunsaturated fatty acids (PUFA) are currently being investigated using
isolated cardiac myocytes. It is still not known whether the incorporation of n−3 PUFA into membrane phospholipids is a prerequisite
for its protective action or if n−3 PUFA exert antiarrhythmic effects in their nonesterified form as demonstrated by recent
studies. Adult porcine cardiomyocytes were grown in media supplemented with arachidonic acid (AA), eicosapentaenoic acid (EPA),
and docosahexaenoic acid (DHA). After 24 h, analysis of total lipids showed that the myocytes were enriched with the respective
fatty acids compared to control cells. Large proportions of all three fatty acids supplemented (69% AA, 72% DHA, and 66% EPA)
remained unesterified. Fatty acid analysis of total phospholipids (PL) revealed that the incorporation of EPA and DHA, though
small, was significantly different (P<0.05) from that of the control cells. The PL fraction was further separated into phosphatidylinositol (Pl), phosphatidylethanolamine,
phosphatidylcholine, and phosphatidylserine to study the pattern of incorporation of the fatty acids in these fractions. It
became apparent that EPA and DHA were selectively incorporated into the Pl fraction. This study demonstrates that in adult
porcine cardiomyocytes, the n−3 PUFA supplementation selectively modulates two important lipid fractions, nonesterified fatty
acid and Pl, which were implicated in the mechanisms of prevention of cardiac arrhythmias. 相似文献
8.
9.
Righi V Di Nunzio M Danesi F Schenetti L Mucci A Boschetti E Biagi P Bonora S Tugnoli V Bordoni A 《Lipids》2011,46(7):627-636
It is well recognized that a high dietary intake of long-chain polyunsaturated fatty acids (LC-PUFA) has profound benefits
on health and prevention of chronic diseases. In particular, in recent years there has been a dramatic surge of interest in
the health effects of n-3 LC-PUFA derived from fish, eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. Notwithstanding,
the metabolic fate and the effects of these fatty acids once inside the cell has seldom been comprehensively investigated.
Using cultured neonatal rat cardiomyocytes as model system we have investigated for the first time, by means of high-resolution
magic-angle spinning nuclear magnetic resonance (HR-MAS NMR) spectroscopy in combination with gas chromatography (GC), the
modification occurring in the cell lipid environment after EPA and DHA supplementation. The most important difference between
control and n-3 LC-PUFA-supplemented cardiomyocytes highlighted by HR-MAS NMR spectroscopy is the increase of signals from
mobile lipids, identified as triacylglycerols (TAG). The observed increase of mobile TAG is a metabolic response to n-3 LC-PUFA
supplementation, which leads to an increased lipid storage. The sequestration of mobile lipids in lipid bodies provides a
deposit of stored energy that can be accessed in a regulated fashion according to metabolic need. Interestingly, while n-3
LC-PUFA supplementation to neonatal rat cardiomyocytes causes a huge variation in the cell lipid environment, it does not
induce detectable modifications in water-soluble metabolites, suggesting negligible interference with normal metabolic processes. 相似文献
10.
Jesuí Vergílio Visentainer Maximiliano D’Addio Noffs Patricia de Oliveira Carvalho Vanessa Vivian de Almeida Cláudio Celestino de Oliveira Nilson Evelázio de Souza 《Journal of the American Oil Chemists' Society》2007,84(6):543-547
Lipid content and fatty acid composition were determined in edible meat of fifteen marine fish species caught on the Southeast
Brazilian coast and two from East Antarctic. Most of the fish had lipid amounts lower than 10% of their total weight. Palmitic
acid (C16:0) predominated, accounting for 54–63% of the total amount of saturated fatty acids. Oleic acid (C18:1n-9) was the
most abundant (49–69%) monounsaturated fatty acid, and docosahexaenoic acid (DHA) was the predominant polyunsaturated fatty
acid (PUFA), accounting for 31–84% of n-3 PUFA. n-3 PUFA level were highest in Antarctic fish meat, comprising 45% of the
total fatty acid content, which consisted of mainly EPA (16.1 ± 1.5 g/100 g lipids) and DHA (24.8 ± 2.4 g/100 g lipids). The
amounts of EPA + DHA in g/100 g of lipids on the Southeast Brazilian coast and Antarctic fish species investigated were found
to be similar: 42.0 ± 1.7 for Bonito cachorro, 41.0 ± 2.3 for Atum, and 39.4 ± 1.8 for peixe porco, respectively. All the
studied species exhibited an n-3/n-6 ratio higher than 3, which confirms the great importance of Southeast Brazilian coast
fish as a significant dietary source of n-3 PUFA. 相似文献
11.
Coralie Schnebelen Stéphane Grégoire Bruno Pasquis Corinne Joffre Catherine P. Creuzot-Garcher Alain M. Bron Lionel Bretillon Niyazi Acar 《Lipids》2009,44(5):465-470
The purpose of this study was to determine whether dietary n-3 and n-6 PUFA may affect retinal PUFA composition and PGE1 and PGE2 production. Male Wistar rats were fed for 3 months with diets containing: (1) 10% eicosapentaenoic acid (EPA) and 7% docosahexaenoic
acid (DHA), or (2) 10% γ-linolenic acid (GLA), or (3) 10% EPA, 7% DHA and 10% GLA, or (4) a balanced diet deprived of EPA,
DHA, and GLA. The fatty acid composition of retinal phospholipids was determined by gas chromatography. Prostaglandin production
was measured by enzyme immunoassay. When compared to rats fed the control diet, the retinal levels of DHA were increased in
rats fed both diets enriched with n-3 PUFA (EPA + DHA and EPA + DHA + GLA diets) and decreased in those supplemented with
n-6 PUFA only (GLA diet). The diet enriched with both n-6 and n-3 PUFA resulted in the greatest increase in retinal DHA. The
levels of PGE1 and PGE2 were significantly increased in retinal homogenates of rats fed with the GLA-rich diet when compared with those of animals
fed the control diet. These higher PGE1 and PGE2 levels were not observed in animals fed with EPA + DHA + GLA. In summary, GLA added to EPA + DHA resulted in the highest
retinal DHA content but without increasing retinal PGE2 as seen in animals supplemented with GLA only. 相似文献
12.
Maud Sabine Cansell Aurélie Battin Pascal Degrace Joseph Gresti Pierre Clouet Nicole Combe 《Lipids》2009,44(3):237-247
The study was undertaken to determine whether eicosapentaenoic acid (EPA, 20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3),
esterified in phospholipids (PL) as liposomes or in triglycerides (TG) as oil, exhibited comparable fates in liver lipids
and whether these fates were associated with gene expressions related to fatty acid (FA) metabolism. PL and TG mixtures with
close contents in EPA and DHA were administered to rats over 2 weeks. Most relevant events occurred after 3 days for both
treatments. At that time, liposomes, compared with oil, increased the liver content in PL with a FA composition enriched in
n-6 FA, comparable in DHA and much lower in EPA. Moreover, liposomes increased the activity and mRNA levels of carnitine palmitoyltransferase
(CPT) I. In contrast, fish oil exerted opposite effects on CPT I and increased the genic expression of lipogenic enzymes.
Liposomes, unlike fish oil, apparently increased the mRNA levels of acyl-CoA oxidase and the activity of the peroxisomal FA-oxidising
system. Concomitantly, mRNA levels of hepatic lipoprotein receptors were increased with both diets, but intracellular proteins
involved in free FA uptake and lipid synthesis were up-regulated only with liposome-treated rats. The quasi absence of EPA
in hepatic PL of liposome-treated rats on the short term could result from increased β-oxidation activities through metabolic
regulations induced by more available free EPA and other PUFA. 相似文献
13.
The particular interest in supplementing human foods with n-3 fatty acids has arisen from the findings that this series of polyunsaturated fatty acids (PUFA) have an impact on neuronal functions. Indeed vertebrates, including humans, preferentially use docosahexaenoic acid (DHA, 22:6n-3) over other long-chain n-3 PUFA for the genesis of their neuronal and retinal membranes. The grey mouse lemur is a nocturnal prosimian primate originating from Madagascar. The increased use of this omnivorous primate in nutritional studies (chronic caloric restriction, n-3 fatty acids supplementation), justifies the interest of determining their fatty acids body composition. In the present study, we report the fatty acid composition in lipid classes from the main target tissues (brain, retina, liver and adipose tissue) of six adult mouse lemurs raised under laboratory nutritional conditions. Among the main findings, n-6-docosapentaenoic acid (n-6-DPA; 22:5n-6) is very low in the brain cortex and retina, whereas there is a very high accumulation of docosahexaenoic acid (DHA, 22:6n-3) in the neural tissues compared to liver and plasma. In particular, DHA accounts for about one half of the total fatty acids in the retina ethanolamine glycerophospholipids. This high concentration clearly indicates that DHA is efficiently transferred from blood lipids to the outer segment of the mouse lemur retina. We conclude that the mouse lemur n-3 PUFA metabolism efficiently drives DHA to neural tissues, through the blood-brain barrier and the blood-retina barrier. 相似文献
14.
Enzymatic modification of trilinolein: Incorporation of n-3 polyunsaturated fatty acids 总被引:2,自引:0,他引:2
Casimir C. Akoh Brenda H. Jennings Dorris A. Lillard 《Journal of the American Oil Chemists' Society》1995,72(11):1317-1321
Two immobilized lipases, IM60 fromMucor miehei and SP435 fromCandida antarctica, were used as biocatalysts for the modification of trilinolein with n-3 polyunsaturated fatty acids (PUFA), such as eicosapentaenoic
acid (EPA) and docosahexaenoic acid (DHA), by using their ethyl esters as acyl donors (EEPA and EDHA, respectively). Transesterification
(ester-ester interchange) reactions were carried out in organic solvent. The products were analyzed according to their equivalent
carbon number and polarity by reverse-phase high-performance liquid chromatography, and the fatty acid profiles were determined
by gas-liquid chromatography. Modified triacylglycerol products contained 1 or 2 molecules of n-3 PUFA. With EEPA as the acyl
donor, the total EPA product yields with IM60 and SP435 as biocatalysts were 79.6 and 81.4%, respectively. However, with EDHA
as the acyl donor and IM60 and SP435 as biocatalysts, the total DHA product yields were 70.5 and 79.7%, respectively. Effects
of reaction parameters, such as type of solvent, enzyme load, time course, and molar ratio of substrates on the n-3 PUFA incorporation,
were followed with SP435 as the biocatalyst. High yields were obtained, even in the absence of organic solvent. These lipids
do hold promise for specialty nutrition and other therapeutic uses. 相似文献
15.
Mathieu Di Miceli Maud Martinat Moïra Rossitto Agns Aubert Shoug Alashmali Clmentine Bosch-Bouju Xavier Fioramonti Corinne Joffre Richard P. Bazinet Sophie Lay 《International journal of molecular sciences》2022,23(12)
Long-chain (LC) n-3 polyunsaturated fatty acids (PUFAs) have drawn attention in the field of neuropsychiatric disorders, in particular depression. However, whether dietary supplementation with LC n-3 PUFA protects from the development of mood disorders is still a matter of debate. In the present study, we studied the effect of a two-month exposure to isocaloric diets containing n-3 PUFAs in the form of relatively short-chain (SC) (6% of rapeseed oil, enriched in α-linolenic acid (ALA)) or LC (6% of tuna oil, enriched in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) PUFAs on behavior and synaptic plasticity of mice submitted or not to a chronic social defeat stress (CSDS), previously reported to alter emotional and social behavior, as well as synaptic plasticity in the nucleus accumbens (NAc). First, fatty acid content and lipid metabolism gene expression were measured in the NAc of mice fed a SC (control) or LC n-3 (supplemented) PUFA diet. Our results indicate that LC n-3 supplementation significantly increased some n-3 PUFAs, while decreasing some n-6 PUFAs. Then, in another cohort, control and n-3 PUFA-supplemented mice were subjected to CSDS, and social and emotional behaviors were assessed, together with long-term depression plasticity in accumbal medium spiny neurons. Overall, mice fed with n-3 PUFA supplementation displayed an emotional behavior profile and electrophysiological properties of medium spiny neurons which was distinct from the ones displayed by mice fed with the control diet, and this, independently of CSDS. Using the social interaction index to discriminate resilient and susceptible mice in the CSDS groups, n-3 supplementation promoted resiliency. Altogether, our results pinpoint that exposure to a diet rich in LC n-3 PUFA, as compared to a diet rich in SC n-3 PUFA, influences the NAc fatty acid profile. In addition, electrophysiological properties and emotional behavior were altered in LC n-3 PUFA mice, independently of CSDS. Our results bring new insights about the effect of LC n-3 PUFA on emotional behavior and synaptic plasticity. 相似文献
16.
Adam H. Metherel William S. Harris Liu Ge Robert A. Gibson Raphaël Chouinard-Watkins Richard P. Bazinet Lei Liu J. Thomas Brenna Juan J. Aristizabal-Henao Ken D. Stark Robert C. Block 《Lipids》2019,54(11-12):755-761
Dried blood spots for fatty acid profiling are increasing in popularity; however, variability in results between laboratories has not been characterized. Whole blood from two subjects (low and high n-3 polyunsaturated fatty acid [PUFA] status) was collected, 25 μL applied to butylated hydroxytoluene (BHT)-treated chromatography strips, dried in air, and shipped to five laboratories. Results were reported as “routine” (typical fatty acids for each laboratory) or “standardized” (a set of 19 fatty acids), and outliers and variability (%CV) were determined. Five and eight outliers of a possible 91 measures each were identified by routine and standardized reporting, respectively, including eicosapentaenoic acid (EPA, 20:5n-3) in the low n-3 PUFA sample and arachidonic acid in the high n-3 PUFA sample. By standardized reporting, no outliers were identified for EPA or docosahexaenoic acid (DHA, 22:6n-3), and %CV decreased from 8.6% to 6.0% and 9.1% to 6.6% for EPA and 10.5% to 7.2% and 10.5% to 6.6% for DHA in the low and high n-3 PUFA sample, respectively. In conclusion, fatty acid profiles yielded few outliers, and standardization of reporting reduced the variability between laboratories. 相似文献
17.
Merzouk SA Saker M Reguig KB Soulimane N Merzouk H Guermouche B Berrouiguet AY Hichami A Narce M Khan NA 《Lipids》2008,43(6):485-497
In this work, we assessed the in-vitro effects of eicosapentaenoic acid (EPA; C20:5n-3) and docosahexaenoic acid (DHA; C22:6n-3) (final concentration, 15 microM) on T cell blastogenesis, interleukin-2 and -4 (IL-2, IL-4) secretion, fatty acid composition and intracellular oxidative status in type I diabetic patients with or without complications. Con A stimulated lymphocyte proliferation, glucose uptake, intracellular reduced glutathione levels and catalase activity were lower in diabetics as compared to controls, regardless to the presence of complications. EPA and DHA diminished T-lymphocyte proliferation and IL-2 production but enhanced IL-4 secretion in both diabetic and control groups. No changes in the levels of reduced glutathione and in the activities of catalase and SOD were observed in control T cells cultured in the presence of EPA and DHA. However, in diabetic patients, addition of n-3 PUFA to culture induced an increase in T cell levels of reduced glutathione and hydroperoxide, and in activities of catalase and SOD. Low levels of arachidonic acid (C20:4n-6) were found in plasma membrane phospholipids of lymphocytes from diabetic patients compared to controls. Incubation of lymphocytes with EPA and DHA was associated with an incorporation of these fatty acids in membrane phospholipids. In conclusion, the beneficial effects of n-3 PUFA on T cell functions in type I diabetes could be attributed to their suppressive action and modulation of cytokine secretion, and to the improvement of intracellular oxidative status. 相似文献
18.
Ziyi Li Shaun P. Kotoski Cynthia T. Srigley 《Journal of the American Oil Chemists' Society》2019,96(5):509-522
Marine oils are commonly added to conventional foods and dietary supplements to enhance their contents of omega-3 polyunsaturated fatty acids (PUFA), including eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3), which have been associated with numerous potential health benefits. This study compared American Oil Chemists’ Society (AOCS) Official Methods Ce 2b-11 and Ce 2c-11 for determining EPA and DHA in foods and dietary supplements and found that AOCS Ce 2c-11 produces significantly higher analyzed values, which could be attributed to a more comprehensive breakdown of the sample matrix and derivatization of fatty acids. Our subsequent food matrix extension validation of AOCS Ce 2c-11 demonstrated that the method produces true, accurate, sensitive, and precise determinations of EPA, DHA, and total omega-3 PUFA in foods and dietary supplements containing added marine oil, including those formulated with emulsified and microencapsulated oils. The method detection limits for EPA and DHA were 0.012 ± 0.002 and 0.011 ± 0.003 mg g−1, respectively (means ± SD). The analyzed contents of EPA (1.26–386 mg serving−1), DHA (1.37–563 mg serving−1), and total omega-3 PUFA (2.69–1270 mg serving−1) were reported for 27 conventional food and dietary supplement products. Eighteen products declared contents of DHA, EPA + DHA, or total omega-3 PUFA on product labels, and the analyzed contents of those fatty acids varied from 95 to 162% of label declarations for all but two of the products. 相似文献
19.
Leon C. Boyd Mei Fong King Brian Sheldon 《Journal of the American Oil Chemists' Society》1992,69(4):325-330
The stability of unsaturated fatty acids to oxidation was monitored by following gas chromatographic (GC) analyses of headspace
volatiles in comparison to changes in polyunsaturated fatty acids (PUFA) and increases in malonaldehydevia the 2-thiobarbituric (TBA) assay. Pure standards of linoleic acid (Lo) and n-3 fatty acids [eicosapentaenoic (EPA) and docosahexaenoic
acid (DHA)] were added to headspace vials, equilibrated in air for 10 min, followed by heating at 80°C in teflon-capped vials
for different time intervals. Headspace analysis showed increases in acetaldehyde, propenal, and propanal, corresponding to
the oxidation of n-3 fatty acids, whereas hexanal production corresponded to losses of linoleic acid. The analysis of propanal
by GC-headspace after only five minutes of heating appeared to be the most effective method of monitoring the oxidation of
n-3 fatty acids, as indicated by correlations between TBA values and loss of PUFA. The oxidation of Lo, EPA and DHA appeared
to be a function of the number of double bonds. Correlations between PUFA depletion, TBA values and volatile formation indicate
that under the prescribed conditions of this experiment, GC-headspace analysis of propanal and pentane/hexanal is an excellent
method for following the oxidation of selected n-3 fatty acids and linoleic acid. 相似文献
20.
Recent studies suggest that dietary krill oil leads to higher omega-3 polyunsaturated fatty acids (n-3 PUFA) tissue accretion compared to fish oil because the former is rich in n-3 PUFA esterified as phospholipids (PL), while n-3 PUFA in fish oil are primarily esterified as triacylglycerols (TAG). Tissue accretion of the same dietary concentrations of PL- and TAG-docosahexaenoic acid (22:6n-3) (DHA) has not been compared and was the focus of this study. Mice (n = 12/group) were fed either a control diet or one of six DHA (1%, 2%, or 4%) as PL-DHA or TAG-DHA diets for 4 weeks. Compared with the control, DHA concentration in liver, adipose tissue (AT), heart, and eye, but not brain, were significantly higher in mice consuming either PL- or TAG-DHA, but there was no difference in DHA concentration in all tissues between the PL- or TAG-DHA forms. Consumption of PL- and TAG-DHA at all concentrations significantly elevated eicosapentaenoic acid (20:5n-3) (EPA) in all tissues when compared with the control group, while docoshexapentaenoic acid (22:5n-6) (DPA) was significantly higher in all tissues except for the eye and heart. Both DHA forms lowered total omega-6 polyunsaturated fatty acids (n-6 PUFA) in all tissues and total monounsaturated fatty acids (MUFA) in the liver and AT; total saturated fatty acid (SFA) were lowered in the liver but elevated in the AT. An increase in the DHA dose, independent of DHA forms, significantly lowered n-6 PUFA and significantly elevated n-3 PUFA concentration in all tissues. Our results do not support the claim that the PL form of n-3 PUFA leads to higher n-3 PUFA tissue accretion than their TAG form. 相似文献