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Public health policies recommend a population wide decrease in the consumption of saturated fatty acids (SFA) to lower the incidence of cardiovascular and metabolic diseases. In most developed countries, milk and dairy products ar...
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Public health policies recommend a population wide decrease in the consumption of saturated fatty acids (SFA) to lower the incidence of cardiovascular and metabolic diseases. In most developed countries, milk and dairy products are the major source of SFA in the human diet. Altering milk fat composition offers the opportunity to lower the consumption of SFA without requiring a change in eating habits. Supplementing the diet of lactating cows with oilseeds, plant oils and marine lipids can be used to replace the SFA in milk fat with monounsaturated fatty acids (MUFA), and to a lesser extent, polyunsaturated fatty acids (PUFA). Due to ruminal metabolism, the decreases in milk SFA are also accompanied by increases in trans fatty acids (TFA), including conjugated isomers. The potential to lower SFA, enrich cis MUFA and PUFA, and alter the abundance and distribution of individual TFA in milk differs according to oil source, form of lipid supplement and degree of oilseed processing, and the influence of other components in the diet. The present review summarises recent evidence on changes in milk fat composition that can be achieved using dietary lipid supplements and highlights the challenges to commercial production of modified milk and dairy products. A meta-analysis on the effects of oilseeds on milk fatty acid composition is also presented. Practical applications: Milk and dairy products are the major source of SFA in the diet in most developed countries. Including oilseeds, plant oils, and to a lesser extent, marine lipids in the diet of lactating cows can replace SFA with MUFA and PUFA in milk offering a mechanism to lower SFA consumption in human populations. Understanding the sources of variation in milk fat composition responses, and adjusting other ingredients in the diet to accommodate lipid supplements offers the opportunity to consistently produce milk with an altered fatty acid composition. However, commercialisation of dedicated supply chains will depend on whether the added costs of production and segregation of modified milk for processing can be recovered at retail.
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Induction of endoplasmic reticulum (ER) stress and apoptosis by elevated exogenous saturated fatty acids (FAs) plays a role in the pathogenesis of beta-cell dysfunction and loss of islet mass in type 2 diabetes. Regulation of mono...
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Induction of endoplasmic reticulum (ER) stress and apoptosis by elevated exogenous saturated fatty acids (FAs) plays a role in the pathogenesis of beta-cell dysfunction and loss of islet mass in type 2 diabetes. Regulation of monounsaturated FA (MUFA) synthesis through FA desaturases and elongases may alter the susceptibility of beta-cells to saturated FA-induced ER stress and apoptosis. Herein, stearoyl-CoA desaturase (SCD)l and SCD2 mRNA expression were shown to be induced in islets from prediabetic hyperinsulinemic Zucker diabetic fatty (ZDF) rats, whereas SCD1, SCD2, and fatty acid elongase 6 (Elovl6) mRNA levels were markedly reduced in diabetic ZDF rat islets. Knockdown of SCD in INS-1 beta-cells decreased desaturation of palmitate to MUFA, lowered FA partitioning into complex neutral lipids, and increased palmitate-induced ER stress and apoptosis. Overexpression of SCD2 increased desaturation of palmitate to MUFA and attenuated palmitate-induced ER stress and apoptosis. Knockdown of Elovl6 limited palmitate elongation to stearate, increasing palmitoleate production and attenuating palmitate-induced ER stress and apoptosis, whereas overexpression of Elovl6 increased palmitate elongation to stearate and palmitate-induced ER stress and apoptosis. Overall, these data support the hypothesis that enhanced MUFA synthesis via upregulation of SCD2 activity can protect beta-cells from elevated saturated FAs, as occurs in prediabetic states. Overt type 2 diabetes is associated with diminished islet expression of SCD and Elovl6, and this can disrupt desaturation of saturated FAs to MUFAs, rendering beta-cells more susceptible to saturated FA-induced ER stress and apoptosis.
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摘要 :
Induction of endoplasmic reticulum (ER) stress and apoptosis by elevated exogenous saturated fatty acids (FAs) plays a role in the pathogenesis of beta-cell dysfunction and loss of islet mass in type 2 diabetes. Regulation of mono...
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Induction of endoplasmic reticulum (ER) stress and apoptosis by elevated exogenous saturated fatty acids (FAs) plays a role in the pathogenesis of beta-cell dysfunction and loss of islet mass in type 2 diabetes. Regulation of monounsaturated FA (MUFA) synthesis through FA desaturases and elongases may alter the susceptibility of beta-cells to saturated FA-induced ER stress and apoptosis. Herein, stearoyl-CoA desaturase (SCD)l and SCD2 mRNA expression were shown to be induced in islets from prediabetic hyperinsulinemic Zucker diabetic fatty (ZDF) rats, whereas SCD1, SCD2, and fatty acid elongase 6 (Elovl6) mRNA levels were markedly reduced in diabetic ZDF rat islets. Knockdown of SCD in INS-1 beta-cells decreased desaturation of palmitate to MUFA, lowered FA partitioning into complex neutral lipids, and increased palmitate-induced ER stress and apoptosis. Overexpression of SCD2 increased desaturation of palmitate to MUFA and attenuated palmitate-induced ER stress and apoptosis. Knockdown of Elovl6 limited palmitate elongation to stearate, increasing palmitoleate production and attenuating palmitate-induced ER stress and apoptosis, whereas overexpression of Elovl6 increased palmitate elongation to stearate and palmitate-induced ER stress and apoptosis. Overall, these data support the hypothesis that enhanced MUFA synthesis via upregulation of SCD2 activity can protect beta-cells from elevated saturated FAs, as occurs in prediabetic states. Overt type 2 diabetes is associated with diminished islet expression of SCD and Elovl6, and this can disrupt desaturation of saturated FAs to MUFAs, rendering beta-cells more susceptible to saturated FA-induced ER stress and apoptosis.
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MUFAs are unsaturated FAs with one double bond and are derived from endogenous synthesis and dietary intake. Accumulating evidence has suggested that plasma and erythrocyte MUFA levels are associated with cardiometabolic disorders...
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MUFAs are unsaturated FAs with one double bond and are derived from endogenous synthesis and dietary intake. Accumulating evidence has suggested that plasma and erythrocyte MUFA levels are associated with cardiometabolic disorders, including CVD, T2D, and metabolic syndrome (MS). Previous genome-wide association studies (GWASs) have identified seven loci for plasma and erythrocyte palmitoleic and oleic acid levels in populations of European origin. To identify additional MUFA-associated loci and the potential functional variant at each locus, we performed ethnic-specific GWAS meta-analyses and trans-ethnic meta-analyses in more than 15,000 participants of Chinese and European ancestry. We identified novel genome-wide significant associations for vaccenic acid at FADS1/2 and PKD2L1 [log(10)(Bayes factor). >= 8.07] and for gondoic acid at FADS1/2 and GCKR [log(10)(Bayes factor) >= 6.22], and also observed improved fine-mapping resolutions at FADS1/2 and GCKR loci. The greatest improvement was observed at GCKR, where the number of variants in the 99% credible set was reduced from 16 (covering 94.8 kb) to 5 (covering 19.6 kb, including a missense variant rs1260326) after trans-ethnic meta-analysis. We also confirmed the previously reported associations of PKD2L1, FADS1/2, GCKR, and HIF1AN with palmitoleic acid and of FADS1/2 and LPCAT3 with oleic acid in the Chinese-specific GWAS and the trans-ethnic meta-analyses. Pathway-based analyses suggested that the identified loci were in unsaturated FA metabolism and signaling pathways.(jl) Our findings provide novel insight into the genetic basis relevant to MUFA metabolism and biology.
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The determination of the fatty acid (FA) profile of milk fat, which is the most complex dietary fat, is more and more for both the definition of nutritional labelling and the study of the genetic variability in bovine milk fat qua...
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The determination of the fatty acid (FA) profile of milk fat, which is the most complex dietary fat, is more and more for both the definition of nutritional labelling and the study of the genetic variability in bovine milk fat quality. For these reasons, the development of infrared techniques for the rapid evaluation of FA profiles is gaining much wider interest. In this research, a method for the rapid determination of saturated, unsaturated, monounsaturated, polyunsaturated and trans FAs, expressed on 100g of total milk FAs, is reported. The FA profile was estimated from the transmission spectrum (optical pathlength of 6mm) obtained from the fat extracted by hot centrifugation, without solvents. Authentic triglyceride standards were used in order to perform the spectral band assignments. The whole data set included 135 raw milk samples collected from cows fed either a total mixed ration or grazed on mountain pastures. Ninety five samples were selected for model development (calibration set); the prediction models were then validated by an independent validation set composed by 40 samples. The prediction model for the saturated FA content showed a correlation coefficient of determination (r~2)=0.96, standard error of prediction (SEP) = 0.97 (g 100g~(-1) of total FAs), ratio of errors (RER)=22.8 and ratio of performance to deviation (RPD)=4.6. Monounsaturated, polyunsaturated and trans FAs provided r~2=0.95, 0.90 and 0.97, RER=20.4, 12.5 and 32.1 and RPD=4.2, 2.8 and 5.2, respectively. The ability to predict the concentration of some saturated single FAs, also grouped according to their chain length, was also investigated. Satisfactory screening performances were found for C14, C16 and C18 FAs, as well as for the amount of the groups including medium (12-17 carbon atoms) and long (18-22 carbon atoms) FAs.
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Fatty acid composition of human milk obtained from 19 breast feeding Kuwaiti mothers and 22 adapted formulas (breast milk substitutes) was determined using capillary gas chromatographic technique. Palmitic acid, and as a consequen...
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Fatty acid composition of human milk obtained from 19 breast feeding Kuwaiti mothers and 22 adapted formulas (breast milk substitutes) was determined using capillary gas chromatographic technique. Palmitic acid, and as a consequence, total saturatedfatty acids were lower in human milk than formula. However, total mono- and polyunsaturated fatty acids were higher in human milk than formula. Linoleic acid content in formula milk was similar to human milk, while alpha-linolenic acid was higher in formula. Evidently formula milk preparations provide essential fatty acids for infants in adequate amounts as a result of their fat blend. Formula milk tends to contain lower percentages of cis- and trans-isomeric fatty acids than human milk. In contrast tohuman milk, most formulas lacked physiologically important long-chain polyunsaturated fatty acids.
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The present prospective study examines proportions of maternal erythrocyte fatty acids across gestation and their association with cord erythrocyte fatty acids in normotensive control (NC) and preeclamptic pregnancies. We hypothes...
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The present prospective study examines proportions of maternal erythrocyte fatty acids across gestation and their association with cord erythrocyte fatty acids in normotensive control (NC) and preeclamptic pregnancies. We hypothesize that maternal fatty acid status in early pregnancy influences fetal fatty acid stores in preeclampsia. 137 NC women and 58 women with preeclampsia were included in this study. Maternal blood was collected at 3 time points during pregnancy (16-20th weeks, 26-30th weeks and at delivery). Cord blood was collected at delivery. Fatty acids were analyzed using gas chromatography. The proportions of maternal erythrocyte alpha-linolenic acid, docosahexaenoic acid, nervonic acid, and monounsaturated fatty acids (MUFA) (p < 0.05 for all) were lower while total n-6 fatty acids were higher (p < 0.05) at 16-20th weeks of gestation in preeclampsia as compared with NC. Cord 18:3n-3, 22:6n-3, 24:1n-9, MUFA, and total n-3 fatty acids (p < 0.05 for all) were also lower in preeclampsia as compared with NC. A positive association was observed between maternal erythrocyte 22:6n-3 and 24:1n-9 at 16-20th weeks with the same fatty acids in cord erythrocytes (p < 0.05 for both) in preeclampsia. Our study for the first time indicates alteration in maternal erythrocyte fatty acids at 16th weeks of gestation which is further reflected in cord erythrocytes at delivery in preeclampsia.
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Camellia oleifera originates from China and is important for the economy of southern China. Seeds from the cultivars LCDG, YAYC, and CR3 of Camellia oleifera were analyzed for their amount of 14 different fatty acids (unsaturated,...
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Camellia oleifera originates from China and is important for the economy of southern China. Seeds from the cultivars LCDG, YAYC, and CR3 of Camellia oleifera were analyzed for their amount of 14 different fatty acids (unsaturated, monounsaturated, polyunsaturated, and saturated). In contrast to former investigations additional kinds of fatty acids could be isolated from Camellia oleifera seeds: The composition of this oil is very similar to olive oil, comprising 67.7–76.7 % oleic acid, 82–84 % unsaturated fatty acids, 68–77 % monounsaturated fatty acids, and 7–14 % polyunsaturated acids. Moreover, Camellia oleifera oil has many advantages to rapeseed oil, peanut oil, soybean oil, safflower seed oil, and especially pig oil.
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摘要 :
Camellia oleifera originates from China and is important for the economy of southern China. Seeds from the cultivars LCDG, YAYC, and CR3 of Camellia oleifera were analyzed for their amount of 14 different fatty acids (unsaturated,...
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Camellia oleifera originates from China and is important for the economy of southern China. Seeds from the cultivars LCDG, YAYC, and CR3 of Camellia oleifera were analyzed for their amount of 14 different fatty acids (unsaturated, monounsaturated, polyunsaturated, and saturated). In contrast to former investigations additional kinds of fatty acids could be isolated from Camellia oleifera seeds: The composition of this oil is very similar to olive oil, comprising 67.7-76.7 % oleic acid, 82-84 % unsaturated fatty acids, 68-77 % monounsaturated fatty acids, and 7-14 % polyunsaturated acids. Moreover, Camellia oleifera oil has many advantages to rapeseed oil, peanut oil, soybean oil, safflower seed oil, and especially pig oil.
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Membrane-bound proteins have been proposed to mediate the transport of long-chain FA (LCFA) transport through the plasma membrane (PM). These proposals are based largely on reports that PM transport of LCFAs can be blocked by a nu...
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Membrane-bound proteins have been proposed to mediate the transport of long-chain FA (LCFA) transport through the plasma membrane (PM). These proposals are based largely on reports that PM transport of LCFAs can be blocked by a number of enzymes and purported inhibitors of LCFA transport. Here, using the ratiometric pH indicator (2 ',7 '-bis-(2-carboxyethyl)-5-(and-6-)-carboxyfluorescein and acrylodated intestinal FA-binding protein-based dual fluorescence assays, we investigated the effects of nine inhibitors of the putative FA transporter protein CD36 on the binding and transmembrane movement of LCFAs. We particularly focused on sulfosuccinimidyl oleate (SSO), reported to be a competitive inhibitor of CD36-mediated LCFA transport. Using these assays in adipocytes and inhibitor-treated protein-free lipid vesicles, we demonstrate that rapid LCFA transport across model and biological membranes remains unchanged in the presence of these purported inhibitors. We have previously shown in live cells that CD36 does not accelerate the transport of unesterified LCFAs across the PM. Our present experiments indicated disruption of LCFA metabolism inside the cell within minutes upon treatment with many of the "inhibitors" previously assumed to inhibit LCFA transport across the PM. Furthermore, using confocal microscopy and a specific anti-SSO antibody, we found that numerous intracellular and PM-bound proteins are SSO-modified in addition to CD36. Our results support the hypothesis that LCFAs diffuse rapidly across biological membranes and do not require an active protein transporter for their transmembrane movement.
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