Disease relevance of oleic acid

• In the presence or absence of cytochalasin, anoxia increased the order parameter, S, of hepatocytes spin-labeled with 12-doxyl stearic acid [1].
• In humans, a reduced erythrocyte stearic acid to oleic acid ratio has been reported in patients with colorectal cancer and it has been proposed that similar changes exist in the cancer tissue [2].
• The LCOs produced by five different Rhizobium loti strains have been purified and were shown to be N-acetylglucosamine pentasaccharides of which the non-reducing residue is N-methylated and N-acylated with cis-vaccenic acid (C18:1) or stearic acid (C18:O) and carries a carbamoyl group [3].
• Long-chain fatty acids, including stearic acid, can cause thrombosis when they are injected into the systemic circulation of animals [4].
• Stearic acid metabolism and atherogenesis: history [5].

High impact information on oleic acid

• We studied the metabolic effects of stearic acid (18:0) on plasma lipoprotein levels in 11 subjects during three dietary periods of three weeks each [6].
• Ethanolamine, myo-inositol, phosphate, and stearic acid were identified as glycolipid components of gel-purified PrP 27-30 [7].
• This was accomplished by the synthesis of a conjugate of VIP and stearic acid (stearyl-VIP) [8].
• UDCA (200 microM) had no effect on either membrane lipid fluidity, assessed by steady-state fluorescence polarization using the probes 1,6-diphenyl-1,3,5-hexatriene, 12-(9-anthroyloxy) stearic acid, and 2-(9-anthroyloxy) stearic acid (2-AS), or Na+,K+-ATPase activity in blLPM vesicles [9].
• In this study, drug-treated cells that were rendered sensitive to killing by anti-Forssman antibody plus GPC, but not antitumor antibody plus GPC, were inhibited in their incorporation of saturated (palmitic or stearic acid), but not an unsaturated, fatty acid (linoleic acid) [10].

Chemical compound and disease context of oleic acid

• Spin label electron spin resonance techniques using a nitroxide derivative of stearic acid were used to detect changes in plasma membrane structure caused by the binding of vesicular stomatitis virus (VSV) to cell plasma membranes of intact BHK-21 cells [11].
• The amount of stearic acid liberated was much larger than that of arachidonic acid between 30 s and 1 min of ischemia [12].
• The antiviral effect of acyclovir elaidate in the female guinea pig model of genital herpes was investigated in a series of experiments [13].
• The HA of influenza B virus contains mainly palmitic acid, whereas the HEF glycoprotein of influenza C virus is acylated with stearic acid which has not been observed before as the prevailing fatty acid in viral or cellular acyl proteins [14].
• There is a striking difference in the percentage plasma NEFA pattern of C.F. patients with pancreatic insufficiency: palmitic, palmitoleic and oleic acid are significantly increased while linoleic, linolenic and stearic acid are decreased (table IV) [15].

Biological context of oleic acid

• To identify the active site in VIP, over 50 related fragments containing an N-terminal stearic acid attachment and an amidated C terminus were designed, synthesized, and tested for neuroprotective properties [16].
• Membrane fluidity was assessed by electron spin resonance (ESR) using a nitroxide-substituted stearic acid analog (5DS) as a spin probe [17].
• Since the interconversion of the input [3H]palmitic acid to stearic acid is even lower in CV1 cells than in insect cells, it follows that only HEF expressed in mammalian, but not in insect cells selects for stearic acid during its biosynthetic acylation [18].
• Benzophenone (BP) was used as a photosensitizer to initiate lipid peroxidation in model and native biological membranes at concentrations of BP that do not perturb bilayer structure, as assessed by stearic acid spin label dynamics [19].
• The resulting down-regulation of the ghSAD-1 gene substantially increased stearic acid from the normal levels of 2% to 3% up to as high as 40%, and silencing of the ghFAD2-1 gene resulted in greatly elevated oleic acid content, up to 77% compared with about 15% in seeds of untransformed plants [20].

Anatomical context of oleic acid

• Depolymerization of microtubules resulted in an increase in the motional freedom of molecular probes in the plasma membranes of Chinese hamster ovary cells expressed by the order parameter, S, measured with two different lipid-soluble spin label probes, 5-doxyl stearic acid and 16-doxyl methylstearate [21].
• Enrichment of the fatty acyl chains with elaidate or the polar headgroups with PE also inhibits fusion, but in contrast to that by 25-OH cholesterol, a significant fraction of the myoblasts are aligned and interacting with each other [22].
• After mitogen stimulation, fatty acid uptake was increased in both lymphocyte types, but cell-specific differences were seen in the distribution of stearic acid among the various cellular lipids [23].
• Stearic acid is toxic for T lymphocytes in vitro but has little effect on B lymphocytes [23].
• Unstimulated T and B cells incorporated identical amounts of stearic acid into six different phospholipids and four neutral lipids [23].

Associations of oleic acid with other chemical compounds

• Remarkably, stearic acid, a saturated fatty acid, could also restore the capping levels in the cholesterol-depleted cells [24].
• Addition of oil body PL or dioleoyl phosphatidylcholine, with or without charged stearylamine/stearic acid, or oleosins, to the medium before sonication provided limited stabilization effects to the TAG droplets [25].
• The degradation of elaidic acid (9-trans-octadecenoic acid), oleic acid, and stearic acid by rat mitochondria was studied to determine whether the presence of a trans double bond in place of a cis double bond or no double bond affects beta-oxidation [26].
• Three spin-labeled derivatives of stearic acid and two derivatives of palmitic acid have been used to study the structure of the strong fatty acid binding site of bovine serum albumin [27].
• Incubation of recombinant enzyme with macrophage membranes and lipid extracts from macrophage membranes resulted in the release of arachidonic acid, as well as, stearic acid, which is enriched at the sn-1 position of macrophage phospholipids [28].

Gene context of oleic acid

• The fatty acids that accumulate in livers of SREBP transgenic mice are 18 carbons rather than 16 carbons in length, suggesting that the enzymes required for the elongation of palmitic to stearic acid may be induced [29].
• Both UFAs are formed in S. cerevisiae by the oxygen- and NADH-dependent desaturation of palmitic acid (C(16:0)) and stearic acid (C(18:0)), respectively, catalyzed by a single integral membrane desaturase encoded by the OLE1 gene [30].
• The findings of this study reveal that IFN-gamma might act on the enzymes controlling the labelling of the sn2 position of phospholipids (linoleic acid) but not the sn1 position (stearic acid), and this increases the polyunsaturated fatty acid content of macrophage membranes [31].
• The current studies suggest that mouse LCE expression is increased by SREBPs and that the enzyme is a component of the elusive mammalian elongation system that converts palmitic to stearic acid [29].
• On normal rodent chow, Cyp27(-/-) mice have 40% larger livers, 45% larger adrenals, 2-fold higher hepatic and plasma triacylglycerol concentrations, a 70% higher rate of hepatic fatty acid synthesis, and a 70% increase in the ratio of oleic to stearic acid in the liver versus Cyp27(+/+) controls [32].

Analytical, diagnostic and therapeutic context of oleic acid

• The titration of alpha-LA by stearic acid results in a fluorescence emission red shift and an apparent stepped increase in fluorescence intensity [33].
• Ten middle-aged males participated in a crossover study to determine the cholesterolemic effect of high amounts of stearic acid in a natural diet [34].
• Determination of the fatty acid component of the major fluorescent substance X3 by gas-liquid chromatography disclosed stearic acid [35].
• Differential scanning calorimetry (DSC) detected decreases of melting entropies (delta Sm) by the incorporation of cholesterol into both anhydrous and hydrated equimolar mixture of pseudo-ceramide (SLE) and stearic acid [36].
• The activity of the enzyme system involved in desaturation of palmitic and stearic acid has been examined in lungs of rats fed fat-free diets supplemented either with 4% safflower oil (controls) or 4% tripalmitin (essential fatty acid (EFA) deficient) both in vivo and in vitro in lung slices [37].

References