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1.
Long‐chain fatty acids (LCFA) are known to activate brown and beige adipocytes. However, very little is known about the effects of the number and the position of double bonds in LCFA with the same length on brown fat‐specific gene expression. To determine the specificity of LCFA in the regulation of these genes in different adipocyte models, fully differentiated 10T1/2, 3T3‐L1, murine, or porcine primary adipocytes (obtained from the subcutaneous fat pad of C57BL/6 mice or Landrace × Yorkshire × Duroc crossbred piglets) were treated with 50 μM of the following 18‐carbon fatty acids: stearic acid (STA; 18:0), oleic acid (OLA; 18:1, Δ9), linoleic acid (LNA; 18:2, Δ9,12), α‐linolenic acid (ALA; 18:3, Δ9,12,15), γ‐linolenic acid (GLA; 18:3, Δ6,9,12), or pinolenic acid (PLA; 18:3, Δ5,9,12) for 24 h with or without 4‐h norepinephrine (NE) treatment. Expression levels of thermoregulatory markers were measured by quantitative real‐time PCR. LNA, ALA, GLA, and PLA upregulated Ucp1 expression and tended to upregulate Pgc1a expression in murine primary adipocytes, but not in 10T1/2, 3T3‐L1, and porcine primary adipocytes. In murine primary adipocytes, NE induced a higher expression of Ucp1 and Pgc1a than non‐NE‐treated cells, and PLA augmented the NE effect. In 10T1/2 cells, NE upregulated Ucp1 and Pgc1a expression, but there was no fatty acid effect. However, 3T3‐L1 cells were insensitive to both fatty acid and beta‐adrenergic agonist stimulation. These results indicate that different adipocyte cell types have different levels of sensitivity to both LCFA and beta agonists in regard to induction of brown fat‐specific gene expression.  相似文献   

2.
Bovine milk fat contains a large variety of structurally different fatty acids. In this study, we describe the presence of aromatic fatty acids in a butter fat sample. Fatty acids were released from butter fat and converted into the corresponding methyl esters (FAME). Urea complexation was used to separate the main saturated fatty acids. GC/MS screening of the FAME in the filtrate of the urea complexation indicated the presence of aromatic fatty acids. By (1) conversion of two representatives into picolinyl esters which were analyzed by GC/MS, (2) linear log tR over carbon number plots (R2 = 0.95) and by the use of two reference standards we were able to show that the phenyl unit was located on the terminal carbon of the straight acyl chain of the FAME. In a fraction gathered by countercurrent chromatography we were able to identify 3‐phenylpropionic acid (Ph‐3:0), 4‐phenylbutyric acid (Ph‐4:0), 5‐phenylpentanoic acid (Ph‐5:0), 6‐phenylhexanoic acid (Ph‐6:0), 7‐phenylheptanoic acid (Ph‐7:0), 8‐phenyloctanoic acid (Ph‐8:0), 9‐phenylnonanoic acid (Ph‐9:0), 10‐phenyldecanoic acid (Ph‐10:0), 11‐phenylundecanoic acid (Ph‐11:0), 12‐phenyldodecanoic acid (Ph‐12:0), 13‐phenyltridecanoic acid (Ph‐13:0), along with one unsaturated phenyldecenoic acid (Ph‐10:1) isomer. Preliminary results indicate that the aromatic fatty acids may have been formed exogenously in the rumen of the cows. The total amount of the aromatic fatty acids was estimated at 0.15 mg/g butter fat, which corresponds with an average daily intake of ~5 mg per day in Germany and ~4.4 mg per day in Europe.  相似文献   

3.
This study investigates the effect of various dietary saturated fatty acid (SFA) profiles on plasma lipid parameters and tissue fatty acid composition in rats. The experiment was designed to monitor polyunsaturated fatty acids (PUFA) levels, while examining different amounts and types of SFA. Four isocaloric diets were prepared, containing 10–11 mol% of fatty acids (FA) as linoleic acid (LNA) and 2.5 mol% as α-linolenic acid (ALA), leading to an identical and well-balanced LNA/ALA ratio. The initial rapeseed oil/corn oil mixture providing ALA and LNA was enriched with olive oil to prepare the olive oil diet. The butterfat diet was supplemented with butterfat, containing short-chain SFA (C4:0–C10:0, 17 mol% of FA), lauric acid (C12:0, 3.2 mol%), myristic acid (C14:0, 10.5 mol%) and palmitic acid (C16:0, 14.5 mol%). The saturates diet was supplemented with trilaurin, trimyristin and tripalmitin to obtain the same level of lauric, myristic and palmitic acids as the butterfat diet, without the short-chain SFA. The trimyristin diet was enriched with trimyristin only. The results showed that the butterfat diet contributed to specific effects, compared to the olive oil diet and the saturates and trimyristin diets: a decrease in plasma total, LDL- and HDL-cholesterol, higher tissue storage of ALA and LNA, and a higher level of (n-3) highly unsaturated fatty acids in some tissues. This study supports the hypothesis that in diets with identical well-balanced LNA/ALA ratios, short chain SFA may decrease circulating cholesterol and increase tissue polyunsaturated fatty acid content in the rat.  相似文献   

4.
Free fatty acids (FFA) in crude rice oil were selectively and stoichiometrically derivatized to fatty acid N,N-dimethylamides (FADMA) by catalytic condensation at 45 °C, and then esterified fatty acids (eFA) were directly converted to fatty acid methyl esters (FAME) at 37 °C. The mixture of FADMA and FAME formed in a single test tube was injected into the capillary column of a gas chromatograph (GC). No mutual contamination occurred between FFA and eFA, and reliability of the method was confirmed by comparison between GC data obtained by this method and by a conventional isolation method. The advantages of the present method are that no FFA isolation procedures are required, the reactions proceed under mild temperature conditions, and FFA and eFA can be analyzed simultaneously by GC.  相似文献   

5.
6.
Patients with cystic fibrosis (CF) exhibit characteristic polyunsaturated fatty acid abnormalities, including low linoleic acid and high arachidonic acid levels that are thought to contribute to the pathophysiology of this disease. Recent studies indicate that changes in fatty acid metabolism are responsible for these abnormalities. This study examines the role of fatty acid substrate concentrations in the development of these alterations in a cultured cell model of CF. By incubating cells with varying concentrations of exogenous fatty acids, it shows that increasing the concentration of substrates from the parallel n-3 and n-6 polyunsaturated fatty acid pathways (linoleic acid and alpha-linolenic acid, respectively) not only increases formation of the products in that pathway, but also reduces metabolism in the parallel pathway. In particular, we demonstrate that high levels of linoleic acid and low levels of alpha-linolenic acid are required to observe the typical fatty acid alterations of cystic fibrosis. These results shed light on the mechanisms of fatty acid metabolic abnormalities in cystic fibrosis. They also have implications for the nutritional therapy of CF, highlighting the importance of specific fatty acid content, and in understanding the anti-inflammatory effects of n-3 fatty acids.  相似文献   

7.
Borage oil [BO: 40.9% linoleic acid (LNA) and 24.0% γ-linolenic acid (GLA)] reverses disrupted epidermal lipid barrier in essential fatty acid deficiency (EFAD). We determined the effects of BO on lamellar body (LB) content and LNA and GLA incorporation into epidermal ceramide 1 (CER1) and epidermal ceramide 2 (CER2), major barrier lipids. EFAD was induced in guinea pigs by a diet of 6% hydrogenated coconut oil (HCO) for 10 weeks (group HCO) or 8 weeks followed by 6% BO for 2 weeks (group HCO + BO). LB content and LNA and GLA incorporation into CER1 were higher in group HCO + BO than in group HCO. Small but significant levels of LNA, GLA, and their C20-metabolized fatty acids [dihomo-γ-linolenic acid (DGLA) and arachidonic acid (ARA)] were incorporated into CER2, where ARA was detected at a level lower than LNA, but DGLA incorporation exceeded that for GLA in group HCO + BO. Dietary BO enhanced LB content and differential incorporation of GLA into CER1 and DGLA into CER2.  相似文献   

8.
Sphaeroforma arctica is a unique, recently discovered marine protist belonging to a group falling close to the yeast/animal border. S. arctica is found in cold environments, and accordingly has a fatty acid composition containing a high proportion of very long chain polyunsaturated fatty acids, including the ω3 polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexanoic acid (DHA). Two elongases and five desaturases, representing the complete set of enzymes necessary for the synthesis of DHA from oleic acid, were isolated from this species and characterized in yeast. One elongase showed high conversion rates on a wide range of 18 and 20 carbon substrates, and was capable of sequential elongation reactions. The second elongase had a strong preference for the 20-carbon fatty acids EPA and arachidonic acid, with over 80 % of EPA converted to docosapentaenoic acid (DPA) in the heterologous yeast host. The isolation of a Δ8-desaturase, along with the detection of eicosadienoic acid in S. arctica cultures indicated that this species uses the alternate Δ8-pathway for the synthesis of long-chain polyunsaturated fatty acids. S. arctica also carried a Δ4-desaturase that proved to be very active in the production of DHA from DPA. Finally, a long chain acyl-CoA synthetase from S. arctica improved DHA uptake in the heterologous yeast host and led to an improvement in desaturation and elongation efficiencies.  相似文献   

9.
We conducted two clinical studies to examine the effects of diets high in stearic acid and lauric + myristic acid on plasma lipids and lipoproteins of healthy young men. In the first study subjects (n = 15) were fed whole food diets high in cocoa butter, butter, olive oil and soybean oil. In the second study, subjects were fed diets very high in saturated fatty acids (> 20% of calories) that were high in either stearic acid (from cocoa butter or milk chocolate) or lauric + myristic acid (from butter). In the first study, cocoa butter elicited a neutral cholesterolemic effect, whereas the butter diet was hypercholesterolemic and the olive oil and soybean oil diets were hypocholesterolemic. In the second study, the diets high in stearic acid did not raise plasma total and LDL-cholesterol levels, whereas, as in the first study, butter was markedly hypercholesterolemic. Regression analyses performed on the individual data from these two clinical studies were conducted to establish the cholesterolemic effects of individual fatty acids. The bestfitting linear regression equations relating ΔTC (change in plasma total cholesterol) was: ΔTC = 2.3 ΔC14:0 + 3.0 ΔC16:0-0.8 ΔC18:0-1.0 ΔPUFA, where Δ fatty acid = change in intake expressed as percent of calories. This predictive equation separates stearic acid from the other long-chain saturated fatty acids and suggests that it has an independent cholesterol-lowering effect. In conclusion, stearic acid is a unique long-chain saturated fatty acid.  相似文献   

10.
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 α‐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.  相似文献   

11.
12.
Chickens can hepatically synthesize eicosapentaenoic acid (20:5 n‐3) and docosahexaenoic acid (22:6 n‐3) from α‐linolenic acid (ALA; 18:3 n‐3); however, the process is inefficient and competitively inhibited by dietary linoleic acid (LNA; 18:2 n‐6). In the present study, the influence of dietary high‐oleic acid (OLA; 18:1 n‐9) soybean oil (HOSO) on egg and tissue deposition of ALA and n‐3 polyunsaturated fatty acids (PUFA) synthesized from dietary ALA was investigated in laying hens fed a reduced‐LNA base diet supplemented with high‐ALA flaxseed oil (FLAX). We hypothesized that reducing the dietary level of LNA would promote greater hepatic conversion of ALA to very long‐chain (VLC; >20C) n‐3 PUFA, while supplemental dietary HOSO would simultaneously further enrich eggs with OLA without influencing egg n‐3 PUFA contents. Nine 51‐week‐old hens each were fed 0, 10, 20, or 40 g HOSO/kg diet for 12 weeks. Within each group, supplemental dietary FLAX was increased every 3 weeks from 0 to 10 to 20 to 40 g/kg diet. Compared to controls, dietary FLAX maximally enriched the total n‐3 and VLC n‐3 PUFA contents in egg yolk by 9.4‐fold and 2.2‐fold, respectively, while feeding hens 40 g HOSO/kg diet maximally attenuated the yolk deposition of ALA, VLC n‐3 PUFA, and total n‐3 PUFA by 37, 15, and 32%, respectively. These results suggest that dietary OLA is not neutral with regard to the overall process by which dietary ALA is absorbed, metabolized, and deposited into egg yolk, either intact or in the form of longer‐chain/more unsaturated n‐3 PUFA derivatives.  相似文献   

13.
Southern bluefin tuna (SBT, Thunnus maccoyii) aquaculture is a highly valuable industry, but research on these fish is hampered by strict catch quotas and the limited success of captive breeding. To address these limitations, we have developed a SBT cell line (SBT-E1) and here we report on fatty acid metabolism in this cell line. The SBT-E1 cells proliferated well in standard Leibovitz’s L-15 cell culture medium containing fetal bovine serum (FBS) as the source of fatty acids. Decreasing the FBS concentration decreased the cell proliferation. Addition of the C18 polyunsaturated fatty acids (PUFA) α-linolenic acid (ALA, 18:3n-3) or linoleic acid (LNA, 18:2n-6) to the cell culture medium had little effect on the proliferation of the cells, whereas addition of the long-chain PUFA (LC-PUFA) arachidonic acid (ARA, 20:4n-6), eicosapentaenoic acid (EPA, 20:5n-3) or docosahexaenoic acid (DHA, 22:6n-3) significantly reduced the proliferation of the cells, especially at higher concentrations and especially for DHA. Addition of vitamin E to the culture medium overcame this effect, suggesting that it was due to oxidative stress. The fatty acid profiles of the total lipid from the cells reflected those of the respective culture media with little evidence for desaturation or elongation of any of the fatty acids. The only exceptions were EPA and ARA, which showed substantial elongation to 22:5n-3 and 22:4n-6, respectively, and DHA, which was significantly enriched in the cells compared with the culture medium. The results are discussed in light of the dietary PUFA requirements of SBT in the wild and in aquaculture.  相似文献   

14.
Highly unsaturated fatty acids (HUFA), including eicosapentaenoic acid (EPA, 20:5n‐3), docosapentaenoic acid (DPA, 22:5n‐3 and 22:5n‐6) and docosahexaenoic acid (DHA, 22:6n‐3), play an important role in human health and nutrition. In this study, concentration of HUFA in free fatty acids (FFA) form by low‐temperature crystallization was investigated. For this purpose, tuna oil (7.1% EPA, 26.8% DHA) was first converted into corresponding FFA. Subsequently, crystallization conditions of various solvent types, the ratio of FFA to acetonitrile, operation temperature and crystallization time were optimized at a small scale of 2 g tuna oil fatty acids. Taking purity and yield into account, the optimum conditions were a 1:10 ratio of FFA to acetonitrile (w/v), ?60 °C, and 1 h. The optimal conditions resulted in concentrations of EPA, DHA and HUFA of 15.1, 58.4 and 79.6%, respectively, with corresponding yields of 61.5, 61.8 and 60.7%, respectively. Crystallization was carried out under the optimal conditions at a large scale of 200 g tuna oil FFA, and a similar concentration result was achieved. After evaporating away the solvent, the residual amount of acetonitrile met the US Pharmacopoeia requirement of <410 ppm. The process for enrichment of HUFA is readily scalable, effective and time‐saving.  相似文献   

15.
Pasquier E  Ratnayake WM  Wolff RL 《Lipids》2001,36(6):567-574
Conifer (pine) seeds are a potential source of dietary oils, but their safety and nutritional properties are not well established. Conifer seed oils differ from common edible vegetable oils in having a series of unusual polyunsaturated fatty acids (PUFA) with a polymethylene-interrupted (PMI) double bond system and a double bond at the Δ5 position. A rat study was conducted to assess whether Δ5 PMI-PUFA of conifer seeds could alter the levels of n−6 and n−3 long-chain polyunsaturated fatty acids (LC-PUFA) in mothers' milk and the developing brain of fetuses and pups. Feeding maritime pine (Pinus pinaster) seed oil (MPO) diet with a Δ5 PMI-PUFA content of 1.4 g/100 g throughout pregnancy and lactation resulted in a large incorporation of Δ5 PMI-PUFA in mothers' milk (5.1±0.5% of total fatty acids). The fetus (17 d old) and pup (22 d) brains, however, accumulated very little (0.6 and 0.4% of total fatty acids, respectively) Δ5 PMI-PUFA. Mother's milk and pup's brain of the MPO group contained normal levels of 20∶4n−6, 22∶4n−6, and 20∶5n−3 compared to a reference group of rats fed a fat blend of sunflower, high-oleic sunflower, and canola oils. The level of 22∶6n−3, however, was slightly but significantly (P<0.05) higher in milk and pup brain of the MPO group. These results show that Δ5 PMI-PUFA of MPO exert no negative effect on the levels of n−6 and n−3 LC-PUFA in rat brain during its early development.  相似文献   

16.
Shin  Kyong-Oh  Kim  Kunpyo  Jeon  Sanghun  Seo  Cho-Hee  Lee  Yong-Moon  Cho  Yunhi 《Lipids》2015,50(10):1051-1056
Ceramide 1 (Cer1), a Cer species with eicosasphingenine (d20:1) amide‐linked to two different ω‐hydroxy fatty acids (C30wh:0:C32wh:1), which are, in turn, ester‐linked to linoleic acid (LNA; 18:2n‐6), plays a critical role in maintaining the structural integrity of the epidermal barrier. Prompted by the recovery of a disrupted epidermal barrier with dietary borage oil [BO: 36.5 % LNA and 23.5 % γ‐linolenic acid (GLA; 18:3n‐6)], in essential fatty acid (EFA)‐deficient guinea pigs, we further investigated the effects of BO on the substitution of ester‐linked GLA for LNA in these two epidermal Cer1 species by LC–MS in positive and negative modes. Dietary supplementation of BO for 2 weeks in EFA‐deficient guinea pigs increased LNA ester‐linked to C32wh:1/d20:1 and C30wh:0/d20:1 of Cer1. Moreover, GLA ester‐linked to C32wh:1/d20:1, but not to C30wh:0/d20:1, of Cer1 was detected, which was further confirmed by the product ions of m/z 277.2 for ester‐linked GLA and m/z 802.3 for the deprotonated C32wh:1/d20:1. C20‐Metabolized fatty acids of LNA or GLA were not ester‐linked to these Cer1 species. Dietary BO induced GLA ester‐linked to C32wh:1/d20:1 of epidermal Cer1.  相似文献   

17.
Several methods are available to extract total lipid and methylate fatty acids from a range of samples including red blood cells (RBC). Fatty acid analysis of human RBC can be undertaken using a two-step extraction and methylation or a combined one-step extraction and methylation procedure. The lipid composition of sheep RBC differs significantly from that of humans and may affect their extraction. The purpose of the current study was to examine the efficiency of extraction of lipid and detection of fatty acids from sheep RBC using a one-step procedure. Fatty acids were analysed using a one-step extraction and methylation procedure using methanol:toluene and acetyl chloride in comparison with a two-step procedure involving extraction of lipid using chloroform:methanol and separate methylation. Concentrations of saturated fatty acids including C16:0 and C18:0 were significantly higher (42.6 and 33.9 % respectively) following extraction using the one-step procedure compared with the two-step procedure. However, concentrations of some polyunsaturated fatty acids, including C20:5n-3 and C22:6n-3 were not significantly different between either procedure. The improved detection of fatty acids may be related to the ability of different solvents to extract different lipid fractions. The differential extraction of lipids and detection of fatty acids from sheep RBC may have important implications in studies examining the effect of dietary treatment on the possible health benefits of fatty acids.  相似文献   

18.
A detailed structural diversity of dienoic fatty acids (FA), including non‐methylene‐interrupted dienoic FA, of triacylglycerols and polar lipids in ovaries of Cellana toreuma was clarified for the first time by using capillary gas chromatography–mass spectrometry of their 3‐pyridylcarbinol esters and argentation thin‐layer chromatography. Interestingly, in addition to 5,9‐octadecadienoic (18:2Δ5,9), 5,9‐eicosadienoic (20:2Δ5,9), 5,9‐heneicosadienoic (21:2Δ5,9), 5,9‐docosadienoic (22:2Δ5,9), 5,9‐tricosadienoic (23:2Δ5,9), and 5,9‐tetracosadienoic (24:2Δ5,9) acids, previously identified in ovaries of C. grata, rare FA 5,9‐hexadecadienoic (16:2Δ5,9), 5,9‐nonadecadienoic (19:2Δ5,9), and 21‐methyl‐5,9‐docosadienoic (iso 23:2Δ5,9) were newly recognized in ovaries of C. toreuma. Detectable amounts of four Δ9,15‐dienoic FA were present in the ovary lipids. The FA identified were one novel 9,15‐heneicosadienoic (21:2Δ9,15) acid and known 9,15‐docosadienoic (22:2Δ9,15), 9,15‐tricosadienoic (23:2Δ9,15), and 9,15‐tetracosadienoic (24:2Δ9,15) acids. The findings help to explain the broad evidence of the structural diversity in marine gastropods and suggest biomarkers to evaluate marine food web relations.  相似文献   

19.
混合脂肪酸的分离   总被引:17,自引:0,他引:17  
陈永  赵辉  江鸿  曹红霞  康定学 《化学世界》2000,41(3):156-159
以一般油脂加工副产物十八碳混合脂肪酸为原料,采用配合结晶梯度冷冻反萃取分离技术,不经任何热处理以避免聚合作用的发生,使混合脂肪酸中的饱和脂肪酸与不饱和脂肪酸分离,同时将不饱和脂肪酸分成油酸和(亚油酸+亚麻酸)两组分。后者含量可达95%以上。  相似文献   

20.
The present study was undertaken to determine the profile of the (n‐9) and (n‐7) isomers for C18:1, C20:1 and C22:1 fatty acids in radish seeds as well as their isomers. Radish (Raphanus sativus L. cvs. ‘Antep, Beyaz, Cherry Belle and Iri K?rm?z?’) seeds were produced in 2003–2005 from different sowing dates (SD). The n‐7 isomers of C18:1, C20:1 and C22:1 ranged from 0.7 to 1.3, 0.1 to 0.3 and 0.4 to 1.1 %, respectively. The average values of C18:1(n‐7) was highest (1 %) amongst the three acids. The ratios of (n‐7)/(n‐9) ranged from 4.5 % (‘Cherry Belle’, SD‐I) to 8.3 % (‘Antep’, SD‐III), 0.8 % (‘Iri K?rm?z?’, SD‐II) to 3 % (‘Iri K?rm?z?’, SD‐I) and 1.6 % (‘Cherry Belle’, SD‐I) to 3.7 % (‘Iri K?rm?z?’, SD‐I) for C18:1, C20:1 and C22:1. Erucic acid was the principal fatty acid with concentrations of nearly 34–39 % in ‘Antep’, 32–34 % in ‘Cherry Belle’, 30–33 % in ‘Beyaz’ and 21–22 % in ‘Ir? K?rm?z?’. The oleic acid content was higher in SD‐I and SD‐II than SD‐III in all cultivars. Correlation studies revealed that palmitoleic acid (C16:1) had a significant relationship between most of the fatty acids of the (n‐7)/(n‐9) family. The results indicated that palmitoleic acid is important in the synthesis of long‐chain fatty acids and that the data for the (n‐7)/(n‐9) ratios for C22:1 could be used as biochemical markers to determine the similarities or differences between radish cultivars.  相似文献   

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