scholarly journals Dietary fat and the diabetic state alter insulin binding and the fatty acyl composition of the adipocyte plasma membrane

1988 ◽  
Vol 253 (2) ◽  
pp. 417-424 ◽  
Author(s):  
C J Field ◽  
E A Ryan ◽  
A B Thomson ◽  
M T Clandinin
Keyword(s):  
Fatty Acids ◽  
Arachidonic Acid ◽  
Plasma Membrane ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Insulin Binding ◽  
Fatty Acyl ◽  
Membrane Composition ◽  
Membrane Phospholipids ◽  
Diabetic State

Control and diabetic rats were fed on semi-purified high-fat diets providing a polyunsaturated/saturated fatty acid ratio (P/S) of 1.0 or 0.25, to examine the effect of diet on the fatty acid composition of major phospholipids of the adipocyte plasma membrane. Feeding the high-P/S diet (P/S = 1.0) compared with the low-P/S diet (P/S = 0.25) increased the content of polyunsaturated fatty acids in membrane phospholipids in both control and diabetic animals. The diabetic state decreased the content of polyunsaturated fatty acids, particularly arachidonic acid, in adipocyte membrane phospholipids. The decrease in arachidonic acid in membrane phospholipids of diabetic animals tended to be normalized to within the control values when high-P/S diets were given. For control animals, altered plasma-membrane composition was associated with change in insulin binding, suggesting that change in plasma-membrane composition may have physiological consequences for insulin-stimulated functions in the adipocyte.

scholarly journals Selective internalization of arachidonic acid by endothelial cells

1987 ◽  
Vol 245 (1) ◽  
pp. 151-157 ◽  
Author(s):  
E R Hall ◽  
C E Manner ◽  
J Carinhas ◽  
R Snopko ◽  
M Rafelson
Keyword(s):  
Fatty Acids ◽  
Endothelial Cells ◽  
Arachidonic Acid ◽  
Endothelial Cell ◽  
Polyunsaturated Fatty Acids ◽  
Cell Types ◽  
Time Dependent ◽  
Asymmetric Distribution ◽  
Membrane Phospholipids ◽  
Bovine Endothelial Cell

The asymmetric distribution of phospholipids in bovine endothelial-cell membranes was probed with 2,4,6-trinitrobenzenesulphonate and purified phospholipase A2. The data suggest that phosphotidylethanolamine is primarily located in the inner lipid bilayer, as reported for other cell types. Stearic acid is taken up by the endothelial cells and is randomly distributed among the membrane phospholipids. In contrast, the polyunsaturated fatty acids (arachidonic, eicosatrienoic and eicosapentaenoic acids) have initial incorporation into the phosphatidylcholine fraction. These fatty acids then undergo a time-dependent transfer from phosphatidylcholine to phosphatidylethanolamine. Thus we propose that endothelial cells possess a mechanism for the selective internalization of polyunsaturated fatty acids.

scholarly journals Some Biogenetic Considerations Regarding the Marine Natural Product (−)-Mucosin

Molecules ◽  
2019 ◽  
Vol 24 (22) ◽  
pp. 4147 ◽  
Author(s):  
Jens M. J. Nolsøe ◽  
Marius Aursnes ◽  
Yngve H. Stenstrøm ◽  
Trond V. Hansen
Keyword(s):  
Fatty Acids ◽  
Natural Products ◽  
Arachidonic Acid ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Natural Product ◽  
Polyunsaturated Fatty Acid ◽  
Marine Natural Product ◽  
Structural Pattern ◽  
Different Origin

Recently, the identity of the marine hydrindane natural product (−)-mucosin was revised to the trans-fused structure 6, thereby providing a biogenetic puzzle that remains to be solved. We are now disseminating some of our insights with regard to the possible machinery delivering the established architecture. Aspects with regard to various modes of cyclization in terms of concerted versus stepwise processes are held up against the enzymatic apparatus known to be working on arachidonic acid (8). To provide a contrast to the tentative polyunsaturated fatty acid biogenesis, the structural pattern featured in (−)-mucosin (6) is compared to some marine hydrinane natural products of professed polyketide descent. Our appraisal points to a different origin and strengthens the hypothesis of a polyunsaturated fatty acids (PUFA) as the progenitor of (−)-mucosin (6).

scholarly journals Resistance of Biomphalaria alexandrina to Schistosoma mansoni and Bulinus truncatus to Schistosoma haematobium Correlates with Unsaturated Fatty Acid Levels in the Snail Soft Tissue

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Marian Elias ◽  
Rasha S. Hanafi ◽  
Samia El-Bardicy ◽  
Ebtisam A. Hafez ◽  
Rashika El Ridi
Keyword(s):  
Fatty Acids ◽  
Arachidonic Acid ◽  
Fatty Acid ◽  
Soft Tissue ◽  
Polyunsaturated Fatty Acids ◽  
Schistosoma Mansoni ◽  
Schistosome Infection ◽  
Bulinus Truncatus ◽  
Biomphalaria Alexandrina ◽  
Arachidonic Acids

Only a fraction of the Biomphalaria and Bulinus snail community shows patent infection with schistosomes despite continuous exposure to the parasite, indicating that a substantial proportion of snails may resist infection. Accordingly, exterminating the schistosome intermediate snail hosts in transmission foci in habitats that may extend to kilometres is cost-prohibitive and damaging to the ecological equilibrium and quality of water and may be superfluous. It may be more cost effective with risk less ecological damage to focus on discovering the parameters governing snail susceptibility and resistance to schistosome infection. Therefore, laboratory bred Biomphalaria alexandrina and Bulinus truncatus snails were exposed to miracidia of laboratory-maintained Schistosoma mansoni and S. haematobium, respectively. Snails were examined for presence or lack of infection association with soft tissue and hemolymph content of proteins, cholesterol, and triglycerides, evaluated using standard biochemical techniques and palmitic, oleic, linoleic, and arachidonic acid, assayed by ultraperformance liquid chromatography-tandem mass spectrometry. Successful schistosome infection of B. alexandrina and B. truncatus consistently and reproducibly correlated with snails showing highly significant (up to P < 0.0001 ) decrease in soft tissue and hemolymph content of the monounsaturated fatty acid, oleic acid, and the polyunsaturated fatty acids, linoleic, and arachidonic acids as compared to naïve snails. Snails that resisted twice infection had soft tissue content of oleic, linoleic, and arachidonic acid similar to naïve counterparts. High levels of soft tissue and hemolymph oleic, linoleic, and arachidonic acid content appear to interfere with schistosome development in snails. Diet manipulation directed to eliciting excessive increase of polyunsaturated fatty acids in snails may protect them from infection and interrupt disease transmission in a simple and effective manner.

scholarly journals Atherosclerosis, Dyslipidemia, and Inflammation: The Significant Role of Polyunsaturated Fatty Acids

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Mariarita Dessì ◽  
Annalisa Noce ◽  
Pierfrancesco Bertucci ◽  
Simone Manca di Villahermosa ◽  
Rossella Zenobi ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Density Lipoprotein ◽  
Endothelial Activation ◽  
Transport Systems ◽  
Low Grade ◽  
Membrane Phospholipids ◽  
Membrane Structure And Function ◽  
Long Chain

Phospholipids play an essential role in cell membrane structure and function. The length and number of double bonds of fatty acids in membrane phospholipids are main determinants of fluidity, transport systems, activity of membrane-bound enzymes, and susceptibility to lipid peroxidation. The fatty acid profile of serum lipids, especially the phospholipids, reflects the fatty acid composition of cell membranes. Moreover, long-chain n-3 polyunsatured fatty acids decrease very-low-density lipoprotein assembly and secretion reducing triacylglycerol production. N-6 and n-3 polyunsatured fatty acids are the precursors of signalling molecules, termed “eicosanoids,” which play an important role in the regulation of inflammation. Eicosanoids derived from n-6 polyunsatured fatty acids have proinflammatory actions, while eicosanoids derived from n-3 polyunsatured fatty acids have anti-inflammatory ones. Previous studies showed that inflammation contributes to both the onset and progression of atherosclerosis: actually, atherosclerosis is predominantly a chronic low-grade inflammatory disease of the vessel wall. Several studies suggested the relationship between long-chain n-3 polyunsaturated fatty acids and inflammation, showing that fatty acids may decrease endothelial activation and affect eicosanoid metabolism.

scholarly journals Arachidonic Acid in Human Milk

Nutrients ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 626 ◽  
Author(s):  
Norman Salem ◽  
Peter Van Dael
Keyword(s):  
Fatty Acids ◽  
Arachidonic Acid ◽  
Fatty Acid ◽  
Human Milk ◽  
Milk Fat ◽  
Dietary Habits ◽  
Chain Polyunsaturated Fatty Acid ◽  
Milk Lipid ◽  
Membrane Phospholipids ◽  
Long Chain

Breastfeeding is universally recommended as the optimal choice of infant feeding and consequently human milk has been extensively investigated to unravel its unique nutrient profile. The human milk lipid composition is unique and supplies specifically long-chain polyunsaturated fatty acids (LC-PUFAs), in particular, arachidonic acid (ARA, 20:4n–6) and docosahexaenoic acid (DHA, 22:6n–3). Arachidonic acid (ARA) is the most predominant long-chain polyunsaturated fatty acid in human milk, albeit at low concentrations as compared to other fatty acids. It occurs predominantly in the triglyceride form and to a lesser extent as milk fat globule membrane phospholipids. Human milk ARA levels are modulated by dietary intake as demonstrated by animal and human studies and consequently vary dependent on dietary habits among mothers and regions across the globe. ARA serves as a precursor to eicosanoids and endocannabinoids that also occur in human milk. A review of scientific and clinical studies reveals that ARA plays an important role in physiological development and its related functions during early life nutrition. Therefore, ARA is an important nutrient during infancy and childhood and, as such, appropriate attention is required regarding its nutritional status and presence in the infant diet. Data are emerging indicating considerable genetic variation in encoding for desaturases and other essential fatty acid metabolic enzymes that may influence the ARA level as well as other LC-PUFAs. Human milk from well-nourished mothers has adequate levels of both ARA and DHA to support nutritional and developmental needs of infants. In case breastfeeding is not possible and infant formula is being fed, experts recommend that both ARA and DHA are added at levels present in human milk.

scholarly journals Omega-3 polyunsaturated fatty acids increase purine but not pyrimidine transport in L1210 leukaemia cells

1996 ◽  
Vol 315 (1) ◽  
pp. 329-333 ◽  
Author(s):  
Danielle MARTIN ◽  
Kelly A. MECKLING-GILL
Keyword(s):  
Fatty Acids ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Acid Composition ◽  
Fold Increase ◽  
Omega 3 ◽  
Membrane Phospholipids ◽  
Epa And Dha ◽  
Long Chain

Here we show that in vitro supplementation of L1210 murine lymphoblastic leukaemia cells with n-3 polyunsaturated fatty acids results in considerable changes in the fatty acid composition of membrane phospholipids. Incubations for 48 h with 30 μM eicosapentaenoic acid (20:5, n-3; EPA) or docosahexaenoic acid (22:6, n-3; DHA) results primarily in substitution of long-chain n-6 fatty acids with long-chain n-3 fatty acids. This results in a decrease in the n-6/n-3 ratio from 6.9 in unsupplemented cultures to 1.2 or 1.6 for EPA and DHA supplemented cultures, respectively. Coincident with these changes in membrane fatty acid composition, we observed a 5-fold increase in the rate of adenosine (5 μM) uptake via the nitrobenzylthioinosine (NBMPR)-sensitive nucleoside transporter in EPA- and DHA- supplemented L1210 cells, relative to unsupplemented cells. This seemed to result from a decrease in the Km for adenosine from 12.5 μM in unsupplemented cultures to 5.1 μM in DHA-treated cultures. Guanosine (50 μM) transport was similarly affected by DHA with a 3.5-fold increase in the initial rate of uptake. In contrast, pyrimidine transport, as measured by uptake of thymidine and cytidine, was not similarly affected, suggesting that substrate recognition had been altered by fatty acid supplementation. Studies using [3H]NBMPR showed that there was no effect of EPA or DHA on either the number of NBMPR-binding sites or the affinity of these sites for NBMPR. This observation suggests that the increases in adenosine and guanosine transport were not due to increases in the number of transporter sites but rather that EPA and DHA directly or indirectly modulate transporter function.

scholarly journals Membrane fluidity is regulated by the C. elegans transmembrane protein FLD-1 and its human homologs TLCD1/2

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Mario Ruiz ◽  
Rakesh Bodhicharla ◽  
Emma Svensk ◽  
Ranjan Devkota ◽  
Kiran Busayavalasa ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Membrane Fluidity ◽  
Polyunsaturated Fatty Acid ◽  
Dietary Fatty Acids ◽  
Editorial Note ◽  
Membrane Phospholipids ◽  
C Elegans ◽  
Long Chain

Dietary fatty acids are the main building blocks for cell membranes in animals, and mechanisms must therefore exist that compensate for dietary variations. We isolated C. elegans mutants that improved tolerance to dietary saturated fat in a sensitized genetic background, including eight alleles of the novel gene fld-1 that encodes a homolog of the human TLCD1 and TLCD2 transmembrane proteins. FLD-1 is localized on plasma membranes and acts by limiting the levels of highly membrane-fluidizing long-chain polyunsaturated fatty acid-containing phospholipids. Human TLCD1/2 also regulate membrane fluidity by limiting the levels of polyunsaturated fatty acid-containing membrane phospholipids. FLD-1 and TLCD1/2 do not regulate the synthesis of long-chain polyunsaturated fatty acids but rather limit their incorporation into phospholipids. We conclude that inhibition of FLD-1 or TLCD1/2 prevents lipotoxicity by allowing increased levels of membrane phospholipids that contain fluidizing long-chain polyunsaturated fatty acids.Editorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (<xref ref-type="decision-letter" rid="SA1">see decision letter</xref>).

Characterization of ω3 fatty acid desaturases from oomycetes and their application toward eicosapentaenoic acid production in Mortierella alpina

2021 ◽  
Author(s):  
Brian K H Mo ◽  
Akinori Ando ◽  
Ryohei Nakatsuji ◽  
Tomoyo Okuda ◽  
Yuki Takemoto ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Arachidonic Acid ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Eicosapentaenoic Acid ◽  
Polyunsaturated Fatty Acid ◽  
Desaturase Activity ◽  
Mortierella Alpina ◽  
Alternative Sources

Abstract ω3 polyunsaturated fatty acids are currently obtained mainly from fisheries, thus sustainable alternative sources such as oleaginous microorganisms are required. Here we describe the isolation, characterization, and application of three novel ω3 desaturases with ω3 polyunsaturated fatty acid-producing activity at ordinary temperatures (28 °C). First, we selected Pythium sulcatum and Plectospira myriandra after screening for oomycetes with high eicosapentaenoic acid/arachidonic acid ratios and isolated the genes psulω3 and pmd17, respectively, which encode ω3 desaturases. Subsequent characterization showed that PSULω3 exhibited ω3 desaturase activity on both C18 and C20 ω6 polyunsaturated fatty acids while PMD17 exhibited ω3 desaturase activity exclusively on C20 ω6 polyunsaturated fatty acids. Expression of psulω3 and pmd17 in the arachidonic acid-producer Mortierella alpina resulted in transformants that produced eicosapentaenoic acid/total fatty acid values of 38% and 40%, respectively, at ordinary temperatures. These ω3 desaturases should facilitate the construction of sustainable ω3 polyunsaturated fatty acid sources.

Controversy in fatty acid balance

1993 ◽  
Vol 71 (9) ◽  
pp. 707-712 ◽  
Author(s):  
John E. Van Aerde ◽  
M. T. Clandinin
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Fish Oil ◽  
Infant Formula ◽  
Acid Content ◽  
Essential Fatty Acids ◽  
Membrane Phospholipids ◽  
Breast Fed ◽  
Long Chain

It is uncertain whether preterm infants can synthesize C20 and C22 (ω−6) and (ω−3) fatty acids required for structural lipids. Dietary intake of CI8:2ω−6 and C18:3ω−3 in formulae lacking long-chain polyunsaturated fatty acids can result in reduced levels of C20 and C22 homologues in membrane phospholipids as compared with breast-fed infants. Supplementation of fish oil has been shown to alleviate this problem in part only, as synthesis and incorporation of arachidonic acid into membrane phospholipids is reduced. Presently, infant formulae do not contain C20 and C22 fatty acids. Feeding an experimental infant formula with a balance between C20 and C22 (ω−6) and (ω−3) fatty acids within the range of human milk results in plasma phospholipid levels of C20 and C22 long-chain polyunsaturated (ω−6) and (ω−3) fatty acids similar to those in breast-fed infants. On the basis of clinical studies and evolutionary data, an increase of the linolenic and a decrease of the linoleic acid content in infant formula are suggested. Balanced incorporation of both (ω−6) and (ω−3) long-chain polyunsaturated fatty acids seems advisable in view of the lack of knowledge concerning the neonate's ability to chain elongate and desaturate essential fatty acids. Recommendations for the essential fatty acid content of preterm infant formula are suggested.Key words: essential fatty acids, long-chain polyunsaturated fatty acids, infant formula, fish oil, desaturation.

scholarly journals Long-chain fatty acids and inflammation

2012 ◽  
Vol 71 (2) ◽  
pp. 284-289 ◽  
Author(s):  
Philip C. Calder
Keyword(s):  
Gene Expression ◽  
Fatty Acids ◽  
Arachidonic Acid ◽  
Fatty Acid ◽  
Inflammatory Cell ◽  
Expression Patterns ◽  
Cell Signalling ◽  
Inflammatory Cells ◽  
Membrane Phospholipids ◽  
Epa And Dha

Inflammation plays a key role in many common conditions and diseases. Fatty acids can influence inflammation through a variety of mechanisms acting from the membrane to the nucleus. They act through cell surface and intracellular receptors that control inflammatory cell signalling and gene expression patterns. Modifications of inflammatory cell membrane fatty acid composition can modify membrane fluidity, lipid raft formation and cell signalling leading to altered gene expression and can alter the pattern of lipid and peptide mediator production. Cells involved in the inflammatory response usually contain a relatively high proportion of the n-6 fatty acid arachidonic acid in their membrane phospholipids. Eicosanoids produced from arachidonic acid have well-recognised roles in inflammation. Oral administration of the marine n-3 fatty acids EPA and DHA increases the contents of EPA and DHA in the membranes of cells involved in inflammation. This is accompanied by a decrease in the amount of arachidonic acid present. EPA is a substrate for eicosanoid synthesis and these are often less potent than those produced from arachidonic acid. EPA gives rise to E-series resolvins and DHA gives rise to D-series resolvins and protectins. Resolvins and protectins are anti-inflammatory and inflammation resolving. Thus, the exposure of inflammatory cells to different types of fatty acids can influence their function and so has the potential to modify inflammatory processes.

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