RESUMO
Long-chain polyunsaturated fatty acids have been associated with aspects of immune regulation including cytokine production. The purpose of this study was to investigate the effect of maternal dietary supplementation with tuna oil, rich in docosahexaenoic acid (DHA), on the concentration of transforming growth factor beta 1 (TGFbeta1) and TGFbeta2 in breast milk. In this randomized, dietary intervention trial, mothers of term infants consumed a daily supplement of 2000 mg oil containing either placebo (n = 40), 300 mg DHA (n = 40), or 600 mg DHA (n = 40). The DHA increase in milk and plasma was proportional to dietary DHA. There was no relationship between milk DHA status and TGFbeta1 and TGFbeta2 levels.
Assuntos
Gorduras Insaturadas na Dieta/administração & dosagem , Ácidos Docosa-Hexaenoicos/administração & dosagem , Leite Humano/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/análise , Ácidos Docosa-Hexaenoicos/sangue , Método Duplo-Cego , Feminino , Óleos de Peixe/administração & dosagem , Humanos , Placebos , Estudos Prospectivos , Fator de Crescimento Transformador beta/análise , Fator de Crescimento Transformador beta1 , Fator de Crescimento Transformador beta2 , AtumRESUMO
The presence of interleukin-12 (IL-12) in 39 samples of human milk was investigated using the enzyme-linked immunosorbent assay. IL-12 (>40 pg/mL) was detected in 24 of the 39 samples collected (1408 +/- 2256 pg/mL, mean +/- SD, n = 24). A range of concentrations of IL-12 was observed in colostrum, transitional, and mature milk, with an apparent decrease in the mean concentration over time postpartum.
Assuntos
Interleucina-12/análise , Leite Humano/imunologia , Adolescente , Adulto , Colostro/imunologia , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Lactente , Recém-Nascido , Período Pós-Parto , Células Th1/imunologia , Células Th2/imunologia , Fatores de TempoRESUMO
Fish oil was fed to rats in combination with an equal amount of olive, sunflower or linseed (flax) oil in semisynthetic diets for 3 weeks. Following stimulation of isolated neutrophils with calcium ionophore the levels of leukotrienes (LT) were determined by HPLC. Graphical presentation of the resultant data show a direct linear relationship between LTB production and substrate concentration with no preferential conversion of n-3 or n-6 substrates. In addition the results highlighted the greater conversion of eicosapentaenoic acid (EPA) and arachidonic acid (AA) to 5-hydroxy metabolites in stimulated neutrophils. There is no suggestion in our results of inhibition of any of the enzymatic conversion steps between EPA or AA and LTB production by any of the dietary fatty acids except by altering the EPA/AA ratio in neutrophil membranes.
Assuntos
Gorduras Insaturadas na Dieta/farmacologia , Lipoxigenase/metabolismo , Neutrófilos/efeitos dos fármacos , Animais , Ácido Araquidônico/sangue , Ácido Eicosapentaenoico/sangue , Ácidos Graxos/sangue , Técnicas In Vitro , Leucotrienos/sangue , Masculino , Lipídeos de Membrana/sangue , Neutrófilos/metabolismo , Ratos , Ratos EndogâmicosRESUMO
Four strains of rat (Dark Agouti, DA; Ginger Hooded, GH; Portion, P; Hooded Wistar, HW) were fed elemental diets containing different sources of fat at the 10% (w/w) level. The dietary fats used included the following oils; olive (rich in oleate), sunflower (rich in linoleate), linseed (rich in alpha-linolenate) and fish (rich in eicosapentaenoate and docosahexaenoate). Differences between strains in response to individual diets were modest compared with the much greater differences achieved by the dietary treatments. In general, the changes in polyunsaturated fatty acid (PUFA) levels in the plasma lipids of all rat strains followed the major PUFA in the diet. There were, however, strong interactions between dietary n-6 and n-3 PUFA which affected not only the level of particular PUFA in lipid fractions but also the lipid fraction in which a particular PUFA appeared. Our findings indicate that a response to dietary fats in the plasma lipids of one strain of rat can be expected to occur with relatively minor variations in other commonly used rat strains.
Assuntos
Gorduras na Dieta/metabolismo , Ácido Eicosapentaenoico/metabolismo , Ácidos Linoleicos/metabolismo , Ácidos Linolênicos/metabolismo , Lipídeos/sangue , Ácidos Oleicos/metabolismo , Animais , Óleos de Peixe , Ácido Linoleico , Óleo de Semente do Linho , Ácido Oleico , Azeite de Oliva , Óleos de Plantas , Ratos , Ratos Endogâmicos , Óleo de Girassol , Ácido alfa-LinolênicoRESUMO
Separation of prostaglandin E3 (PGE3) from prostaglandin E2 (PGE2) and prostaglandin E1 (PGE1) was achieved following derivatization with p-(9-anthroyloxy)phenacyl bromide (panacyl bromide). The eicosanoid esters were analysed by reverse phase high pressure liquid chromatography with fluorometric detection (excitation 360nm and emission 470nm). Human, rat and mouse adherent cells were incubated overnight and the culture medium extracted, derivatized and analysed for PG production. PGE2 was detected from biological samples of each species tested. PGE2 synthesis was reduced when cells were incubated overnight with 5 microM eicosapentaenoic acid. PGE3 was not detectable under these experimental conditions. Studies were also undertaken using adherent cells from mice, rats and human subjects given dietary fish oil supplements rich in EPA. PGE3 production by these cells was not detected although the dietary regimens yielded substantial incorporation of EPA into cell membranes and leukocyte LTB5 production was demonstrable.
Assuntos
Alprostadil/análogos & derivados , Alprostadil/análise , Dinoprostona/análise , Alprostadil/sangue , Animais , Células Cultivadas/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Dieta , Dinoprostona/análogos & derivados , Dinoprostona/sangue , Ácidos Eicosanoicos/metabolismo , Esterificação , Ácidos Graxos/análise , Corantes Fluorescentes , Humanos , Leucócitos Mononucleares/metabolismo , Macrófagos/metabolismo , Camundongos , Ratos , Baço/químicaRESUMO
Inflamed rats with adjuvant-induced polyarthritis showed similar incorporation of dietary eicosapentaenoic acid (EPA) into peritoneal exudate cell (PEC) membrane phospholipids compared to pair fed non-inflamed control rats. Arachidonic acid (AA) content was similar in PEC phospholipids of inflamed and control rats whereas the linoleic acid content was consistently higher in inflamed rats.
Assuntos
Artrite Experimental/metabolismo , Ácidos Graxos/metabolismo , Óleos de Peixe/administração & dosagem , Fosfolipídeos/metabolismo , Animais , Ácido Araquidônico/metabolismo , Membrana Celular/metabolismo , Gorduras Insaturadas na Dieta/administração & dosagem , Ácido Eicosapentaenoico/metabolismo , Leucócitos/metabolismo , Masculino , Cavidade Peritoneal/citologia , Ratos , Ratos EndogâmicosRESUMO
We examined the influence of mixtures of dietary fish oil and three vegetable oils (linseed, olive and sunflower) on the incorporation of dietary eicosapentaenoic acid (EPA) into rat leucocyte phospholipids and the subsequent metabolism of EPA and arachidonic acid by 5-lipoxygenase. Eicosapentaenoic acid in leucocyte phospholipids of fish oil-fed rats was decreased by the addition of each vegetable oil to the dietary fish oil, with sunflower oil, the oil highest in linoleate (LA), having the largest EPA-lowering effect (66% decrease). The rate of synthesis of leukotriene B4 (LTB4) was increased by the addition of each vegetable oil to the basic fish oil diet, with sunflower oil having a significant effect on LTB4 synthesis (145% increase). The effects of olive oil (enriched in oleate) were similar to those of linseed oil (enriched in alpha-linolenic acid) with regard to EPA incorporation (mean decrease = 30%) and LTB4 synthesis (mean increase = 72%). The level of arachidonic acid in leucocyte membranes and the rate of synthesis of LTB4 were proportional to the level of dietary LA added to the basic fish oil diet. The results indicate that olive or linseed oil ingested in combination with fish oil have less effect than does sunflower oil on leucocyte EPA content and LTB4 production. They further suggest that, when ingested with fish oil, dietary linoleic acid is more important than oleate or alpha-linolenic acid as a determinant of these variables.
Assuntos
Óleos de Peixe/metabolismo , Leucócitos/metabolismo , Leucotrieno B4/biossíntese , Óleos de Plantas/metabolismo , Animais , Ácidos Araquidônicos/metabolismo , Células Cultivadas , Gorduras Insaturadas na Dieta/metabolismo , Ácido Eicosapentaenoico/metabolismo , Ácidos Graxos/análise , Helianthus , Leucócitos/química , Óleo de Semente do Linho/metabolismo , Masculino , Neutrófilos/química , Neutrófilos/metabolismo , Azeite de Oliva , Fosfolipídeos/análise , Ratos , Ratos Endogâmicos , Óleo de GirassolRESUMO
We examined the influence of various dietary oils, including linseed and fish oil on the relative rates of leukotriene B4 (LTB4) and LTB5 production by rat peritoneal exudate cells in five rat strains. While there was an association between the membrane phospholipid levels of the fatty acid precursors (arachidonic acid (AA) and eicosapentaenoic acid (EPA)) and the rate of synthesis of their respective 5-lipoxygenase products (LTB4 and LTB5), the rate of LTB4 synthesis was a combined function of both AA and EPA levels. We observed a strong linear relationship (correlation coefficient = 0.99) between the ratio of EPA/AA in the cell membrane phospholipids and the ratio of LTB5/LTB4 produced by these cells in vitro; this association was independent of genetic (strain) variability and was independent of the source of EPA (dietary EPA or EPA endogenously synthesized from dietary alpha-linolenic acid).