scholarly journals Modulation of human type II secretory phospholipase A2 by sphingomyelin and annexin VI

1997 ◽  
Vol 326 (1) ◽  
pp. 227-233 ◽  
Author(s):  
Kamen KOUMANOV ◽  
Claude WOLF ◽  
Gilbert BÉREZIAT
Keyword(s):  
Fatty Acids ◽  
Polyunsaturated Fatty Acids ◽  
Phospholipase A2 ◽  
Cell Membranes ◽  
Red Cell ◽  
Type Ii ◽  
Membrane Phospholipids ◽  
Human Type ◽  
Annexin Vi ◽  
Hydrolysis Of

Conjectural results have been reported on the capacity of inflammatory secreted phospholipase A2 (sPLA2) to hydrolyse mammalian membrane phospholipids. Development of an assay based on the release of non-esterified fatty acids by the enzyme acting on the organized phospholipid mixture constituting the membrane matrix has led to the identification of two prominent effectors, sphingomyelin (SPH) and annexin. Recombinant human type II sPLA2 hydrolyses red-cell membrane phospholipids with a marked preference for the inner leaflet. This preference is apparently related to the high content of SPH in the outer leaflet, which inhibits sPLA2. This inhibition by SPH is specific for sPLA2. Cholesterol counteracts the inhibition of sPLA2 by SPH, suggesting that the SPH-to-cholesterol ratio accounts in vivo for the variable susceptibility of cell membranes to sPLA2. Different effects were observed of the presence of the non-hydrolysable D-α-dipalmitoyl phosphatidylcholine (D-DPPC), which renders the membranes rigid but does not inhibit sPLA2. Annexin VI was shown, along with other annexins, to inhibit sPLA2 activity by sequestering the phospholipid substrate. The present study has provided the first evidence that annexin VI, in concentrations that inhibit hydrolysis of purified phospholipid substrates, stimulated the hydrolysis of membrane phospholipids by sPLA2. The activation requires the presence of membrane proteins. The effect is specific for type II sPLA2 and is not reproducible with type I PLA2. The activation by annexin VI of sPLA2 acting on red cell membranes results in the preferential release of polyunsaturated fatty acids. It suggests that type II sPLA2, in conjunction with annexin VI, might be involved in the final step of endocytosis and/or exocytosis providing the free polyunsaturated fatty acids acting synergistically to cause membrane fusion.

Lipids of the fin whale (Balaenoptera physalus) from North Atlantic waters. IV. Fin whale milk

1968 ◽  
Vol 46 (3) ◽  
pp. 197-203 ◽  
Author(s):  
R. G. Ackman ◽  
C. A. Eaton ◽  
S. N. Hooper
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Total Lipid ◽  
Iodine Value ◽  
North Atlantic ◽  
Methyl Esters ◽  
Short Chain Fatty Acids ◽  
Fin Whale ◽  
Hydrolysis Of

Fatty acid compositions were determined for total lipid (17.5% of the milk and > 95% triglycerides), 2-monoglyceride obtained by enzymatic hydrolysis of isolated triglyceride, and isolated phospholipid (~1% of total lipids). The total lipid fatty acids of the milk had a composition similar to fin whale depot fat but were enriched in hexadecanoic acid and polyunsaturated fatty acids at the expense of monoethylenic acids; correspondingly the iodine value of 136 (methyl esters) was higher than the normal range (105–120) of North Atlantic fin whale blubber oils. Over 80% of the fatty acids in the 2-position of the triglycerides were accounted for by relatively short chain fatty acids, especially hexadecanoic (54.6%), tetradecanoic (13.7%), and hexadecenoic (11.2%), so that the ester iodine value was only 48. The milk phospholipids had a fatty acid composition basically similar to that of liver phospholipids (methyl ester iodine value 120) with somewhat more polyunsaturated fatty acids and accordingly an iodine value of 144 for methyl esters.

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.

Hydrocortisone inhibits mucin secretion from guinea pig gallbladder

1984 ◽  
Vol 247 (4) ◽  
pp. G427-G431 ◽  
Author(s):  
J. R. Moore ◽  
B. S. Turner ◽  
J. T. LaMont
Keyword(s):  
Guinea Pig ◽  
Phospholipase A2 ◽  
Sodium Succinate ◽  
Inhibitory Effect ◽  
Membrane Phospholipids ◽  
Mucin Secretion ◽  
Basal Secretion ◽  
Prostaglandin Release ◽  
Hydrolysis Of

We studied the effects of hydrocortisone, an inhibitor of phospholipase A2, on the secretion of mucin and release of prostaglandins from guinea pig gallbladder explants. We measured mucin using [3H]glucosamine as a precursor and prostaglandins by radioimmunoassay of 6-keto-prostaglandin F1 alpha. Mucin secretion and prostaglandin release were studied under basal conditions and after arachidonate stimulation. Hydrocortisone sodium succinate reversibly inhibited basal secretion of mucin by 24% at 10(-5) M (P less than 0.05 compared with control) and 34% at 10(-4) M (P less than 0.01). Hydrocortisone, 10(-4) M, also reversibly inhibited arachidonate-stimulated secretion of mucin (P less than 0.01 compared with controls incubated with arachidonate alone). Release of prostaglandin F1 alpha was significantly inhibited by hydrocortisone under basal (P less than 0.01) and arachidonate-stimulated (P less than 0.01) conditions. The inhibitory effect of hydrocortisone was mediated by inhibition of hydrolysis of arachidonate from membrane phospholipids, suggesting that exogenous arachidonate is incorporated into membrane phospholipids prior to conversion to prostaglandins.

scholarly journals The Efficacy of Polyunsaturated Fatty Acids as Protectors against Calcium Oxalate Renal Stone Formation: A Review

Nutrients ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1069
Author(s):  
Allen L. Rodgers ◽  
Roswitha Siener
Keyword(s):  
Fatty Acids ◽  
Polyunsaturated Fatty Acids ◽  
Fish Oil ◽  
Calcium Oxalate ◽  
Renal Stone ◽  
Stone Formation ◽  
Membrane Phospholipids ◽  
Dietary Pufa ◽  
Evening Primrose ◽  
Different Types

In the pathogenesis of hypercalciuria and hyperoxaluria, n-6 polyunsaturated fatty acids (PUFAs) have been implicated by virtue of their metabolic links with arachidonic acid (AA) and prostaglandin PGE2. Studies have also shown that n-3 PUFAs, particularly those in fish oil—eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)—can serve as competitive substrates for AA in the n-6 series and can be incorporated into cell membrane phospholipids in the latter’s place, thereby reducing urinary excretions of calcium and oxalate. The present review interrogates several different types of study which address the question of the potential roles played by dietary PUFAs in modulating stone formation. Included among these are human trials that have investigated the effects of dietary PUFA interventions. We identified 16 such trials. Besides fish oil (EPA+DHA), other supplements such as evening primrose oil containing n-6 FAs linoleic acid (LA) and γ-linolenic acid (GLA) were tested. Urinary excretion of calcium or oxalate or both decreased in most trials. However, these decreases were most prominent in the fish oil trials. We recommend the administration of fish oil containing EPA and DHA in the management of calcium oxalate urolithiasis.

scholarly journals The Anti-Inflammatory and Antioxidant Properties of n-3 PUFAs: Their Role in Cardiovascular Protection

Biomedicines ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 306 ◽  
Author(s):  
Francesca Oppedisano ◽  
Roberta Macrì ◽  
Micaela Gliozzi ◽  
Vincenzo Musolino ◽  
Cristina Carresi ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Polyunsaturated Fatty Acids ◽  
Vascular Reactivity ◽  
Molecular Mechanisms ◽  
Antioxidant Properties ◽  
Cardiac Cells ◽  
Membrane Phospholipids ◽  
Mitochondrial Functions ◽  
Anti Inflammatory ◽  
Inflammatory Effect

Polyunsaturated fatty acids (n-3 PUFAs) are long-chain polyunsaturated fatty acids with 18, 20 or 22 carbon atoms, which have been found able to counteract cardiovascular diseases. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in particular, have been found to produce both vaso- and cardio-protective response via modulation of membrane phospholipids thereby improving cardiac mitochondrial functions and energy production. However, antioxidant properties of n-3 PUFAs, along with their anti-inflammatory effect in both blood vessels and cardiac cells, seem to exert beneficial effects in cardiovascular impairment. In fact, dietary supplementation with n-3 PUFAs has been demonstrated to reduce oxidative stress-related mitochondrial dysfunction and endothelial cell apoptosis, an effect occurring via an increased activity of endogenous antioxidant enzymes. On the other hand, n-3 PUFAs have been shown to counteract the release of pro-inflammatory cytokines in both vascular tissues and in the myocardium, thereby restoring vascular reactivity and myocardial performance. Here we summarize the molecular mechanisms underlying the anti-oxidant and anti-inflammatory effect of n-3 PUFAs in vascular and cardiac tissues and their implication in the prevention and treatment of cardiovascular disease.

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 Inhibition by unsaturated fatty acids of type II secretory phospholipase A2 synthesis in guinea-pig alveolar macrophages

2000 ◽  
Vol 267 (12) ◽  
pp. 3633-3639 ◽  
Author(s):  
Mounia Alaoui El Azher ◽  
Nathalie Havet ◽  
Monique Singer ◽  
Claude Dumarey ◽  
Lhousseine Touqui
Keyword(s):  
Fatty Acids ◽  
Guinea Pig ◽  
Phospholipase A2 ◽  
Alveolar Macrophages ◽  
Unsaturated Fatty Acids ◽  
Type Ii ◽  
Secretory Phospholipase A2 ◽  
Secretory Phospholipase

scholarly journals Improvement of the probiotic effect of micro-organisms by their combination with maltodextrins, fructo-oligosaccharides and polyunsaturated fatty acids

2002 ◽  
Vol 88 (S1) ◽  
pp. S95-S99 ◽  
Author(s):  
A. Bomba ◽  
R. Nemcová ◽  
S. Gancarcíková ◽  
R. Herich ◽  
P. Guba ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Polyunsaturated Fatty Acids ◽  
Dietary Lipids ◽  
Control Group ◽  
Jejunal Mucosa ◽  
Gastrointestinal Microbiota ◽  
Weanling Piglets ◽  
Micro Organisms ◽  
Hydrolysis Of ◽  
Gnotobiotic Piglets

Probiotics could represent an effective alternative to the use of synthetic substances in nutrition and medicine. The data concerning the efficacy of probiotics are often contradictory. This paper focuses on the enhancement of the efficacy of probiotics by their combination with synergistically acting components of natural origin. Maltodextrins can be obtained by enzymatic hydrolysis of starch and are suitable for consumption. Administration ofLactobacillus paracaseitogether with maltodextrin decreased the number ofEscherichia colicolonising the jejunal mucosa of gnotobiotic piglets by 1 logarithm compared to the control group. Fructo-oligosaccharides (FOS) are naturally occurring oligosaccharides, mainly of plant origin.L. paracaseiadministered in combination with FOS significantly increased counts ofLactobacillusspp.,Bifidobacteriumspp., total anaerobes and total aerobes compared to the control group as well as theL. paracaseigroup. It also significantly decreasedClostridiumandEnterobacteriumcounts in the faeces of the weanling piglets compared with the control group. Dietary lipids influence the gastrointestinal microbiota and specifically the population of lactic acid bacteria. In gnotobiotic piglets the oral administration of an oil containing polyunsaturated fatty acids (PUFA) significantly increased the number ofL. paracaseiadhering to jejunal mucosa compared to the control group. Our results showed that maltodextrin KMS X-70 and PUFA can be used to enhance the effect of probiotic micro-organisms in the small intestine, and similarly FOS enhance the effect of probiotic micro-organisms in the large intestine.

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