Reduction In Polyunsaturated Fatty Acids Research Articles

Development of marker-free transgenic Jatropha plants with increased levels of seed oleic acid

BackgroundJatropha curcas is recognized as a new energy crop due to the presence of the high amount of oil in its seeds that can be converted into biodiesel. The quality and performance of the biodiesel depends on the chemical composition of the fatty acids present in the oil. The fatty acids profile of the oil has a direct impact on ignition quality, heat of combustion and oxidative stability. An ideal biodiesel composition should have more monounsaturated fatty acids and less polyunsaturated acids. Jatropha seed oil contains 30% to 50% polyunsaturated fatty acids (mainly linoleic acid) which negatively impacts the oxidative stability and causes high rate of nitrogen oxides emission.ResultsThe enzyme 1-acyl-2-oleoyl-sn-glycero-3-phosphocholine delta 12-desaturase (FAD2) is the key enzyme responsible for the production of linoleic acid in plants. We identified three putative delta 12 fatty acid desaturase genes in Jatropha (JcFAD2s) through genome-wide analysis and downregulated the expression of one of these genes, JcFAD2-1, in a seed-specific manner by RNA interference technology. The resulting JcFAD2-1 RNA interference transgenic plants showed a dramatic increase of oleic acid (> 78%) and a corresponding reduction in polyunsaturated fatty acids (< 3%) in its seed oil. The control Jatropha had around 37% oleic acid and 41% polyunsaturated fatty acids. This indicates that FAD2-1 is the major enzyme responsible for converting oleic acid to linoleic acid in Jatropha. Due to the changes in the fatty acids profile, the oil of the JcFAD2-1 RNA interference seed was estimated to yield a cetane number as high as 60.2, which is similar to the required cetane number for conventional premium diesel fuels (60) in Europe. The presence of high seed oleic acid did not have a negative impact on other Jatropha agronomic traits based on our preliminary data of the original plants under greenhouse conditions. Further, we developed a marker-free system to generate the transgenic Jatropha that will help reduce public concerns for environmental issues surrounding genetically modified plants.ConclusionIn this study we produced seed-specific JcFAD2-1 RNA interference transgenic Jatropha without a selectable marker. We successfully increased the proportion of oleic acid versus linoleic in Jatropha through genetic engineering, enhancing the quality of its oil.

Antioxidant profile of strawberry tree honey and its marker homogentisic acid in several models of oxidative stress

The antioxidant activity of several honeys was evaluated considering the different contribution of entire samples. The strawberry tree honey emerged as the richest in total phenols and the most active honey in the DPPH and FRAP tests, and could protect cholesterol against oxidative degradation (140°C). Homogentisic acid (2,5-dihydroxyphenylacetic acid, HGA), the main phenolic compound from strawberry tree honey, showed interesting antioxidant and antiradical activities, and protective effect against thermal-cholesterol degradation, comparable to those of well known antioxidants. Moreover, the pre-treatment with HGA significantly preserved liposomes and LDL from Cu2+-induced oxidative damage at 37°C for 2h, inhibiting the reduction of polyunsaturated fatty acids and cholesterol and the increase of their oxidative products. This phenol had no toxic effect in human intestinal epithelial Caco-2 cells within the concentration range tested (5–1000μM). HGA was able to pass through the Caco-2 monolayers, the apparent permeability coefficients (Papp) in the apical-to-basolateral and basolateral-to-apical direction were 3.48±1.22×10−6 and 2.18±0.34×10−6cm/s, respectively, suggesting a passive diffusion pathway as the dominating process. The results of the work qualify HGA as natural antioxidant, able to exert a significant in vitro protective effect and to contribute to the strawberry tree honey antioxidant activity.

Protective role of arzanol against lipid peroxidation in biological systems

This study examines the protective effect of arzanol, a pyrone–phloroglucinol etherodimer from Helichrysum italicum subsp. microphyllum, against the oxidative modification of lipid components induced by Cu2+ ions in human low density lipoprotein (LDL) and by tert-butyl hydroperoxide (TBH) in cell membranes. LDL pre-treatment with arzanol significantly preserved lipoproteins from oxidative damage at 2h of oxidation, and showed a remarkable protective effect on the reduction of polyunsaturated fatty acids and cholesterol levels, inhibiting the increase of oxidative products (conjugated dienes fatty acids hydroperoxides, 7β-hydroxycholesterol, and 7-ketocholesterol). Arzanol, at non-cytotoxic concentrations, exerted a noteworthy protection on TBH-induced oxidative damage in a line of fibroblasts derived from monkey kidney (Vero cells) and in human intestinal epithelial cells (Caco-2), decreasing, in both cell lines, the formation of oxidative products (hydroperoxides and 7-ketocholesterol) from the degradation of unsaturated fatty acids and cholesterol. The cellular uptake and transepithelial transport of the compound were also investigated in Caco-2 cell monolayers. Arzanol appeared to accumulate in Caco-2 epithelial cells. This phenol was able to pass through the intestinal Caco-2 monolayers, the apparent permeability coefficients (Papp) in the apical-to-basolateral and basolateral-to-apical direction at 2h were 1.93±0.36×10−5 and 2.20±0.004×10−5cm/s, respectively, suggesting a passive diffusion pathway. The results of the work qualify arzanol as a potent natural antioxidant with a protective effect against lipid oxidation in biological systems.

Chemical composition and antioxidant activities of Myrtus communis L. berries extracts

Myrtle ( Myrtus communis L.) berries extracts were prepared with solvents at different polarity (water, ethanol, and ethyl acetate) and analysed using different in vitro tests in order to evaluate their antioxidant properties. Antiradical and total antioxidant activities were measured with DPPH and FRAP tests, respectively. Their ability to protect biological molecules was assessed using the cholesterol and LDL oxidation assays. In addition, phenolic compounds and unsaturated fatty acids composition was analysed by HPLC–DAD and HPLC–MS/MS. Ethanol and water extracts showed the highest amount of extracted compounds, but the highest antiradical and antioxidant activities were found in ethanol and ethyl acetate extracts. These extracts were also the ones with the highest content of phenolic compounds. In addition, our results showed a highly significant correlation between the amount of total phenols and antiradical ( R 2 = 0.9993) or antioxidant activities ( R 2 = 0.9985) in these extracts. HPLC–DAD and HPLC–MS analyses showed significant quantitative and qualitative differences among these three extracts. The ethyl acetate extract had the highest protective effect in assays of thermal (140 °C) cholesterol degradation and Cu 2+-mediated LDL oxidation, inhibiting the reduction of polyunsaturated fatty acids and cholesterol, and the increase of their oxidative products. These results suggest that because of these properties, myrtle berries could be used in dietary supplements preparations or as food additives.

Protective effect and relation structure-activity of nonivamide and iododerivatives in several models of lipid oxidation

The introduction of an iodine atom on the vanillyl moiety of nonivamide causes a switch in the vanilloid activity (TRPV1 antagonism versus TRPV1 desensitization) and nullifies the aversive properties of capsaicinoids. In the present study we investigated the effect of iodination in the vanillyl moiety on the antioxidant activity of capsaicinoids. To this aim, we have compared the protective effects of nonivamide and three iododerivatives, 2-iodononivamide (2IN), 5-iodononivamide (5IN), and 6-iodononivamide (6IN) in a series of in vitro models of lipid oxidation, namely the autoxidation and the FeCl 3-mediated oxidation of linoleic acid at 37 °C and the thermal (140 °C), solvent-free oxidation of cholesterol. All tested compounds could protect linoleic acid and cholesterol against oxidative degradation, the order of potency being: nonivamide > 5IN > 6IN ≈ 2IN. Our results show that, in general, the introduction of an iodine atom on the vanillyl moiety of nonivamide causes a decrease in the antioxidant activity, and this effect is sensitive to the position of iodine on the aromatic ring, with 5IN substantially retaining the efficacy of nonivamide to protect linoleic and cholesterol against free radical attack. Moreover, the pre-treatment with 5IN, at noncytotoxic concentrations, significantly preserved LDL from Cu 2+-induced oxidative damage at 37 °C for 2 h, inhibiting the reduction of polyunsaturated fatty acids and cholesterol and the increase of their oxidative products. The results of the present work suggest that 5IN exerts useful antioxidant properties in different in vitro systems of lipid peroxidation. This, coupled to its lacks of pungency and TRPV1 inhibiting properties, qualifies this phenolic compound as an attractive candidate for further investigations in vivo.

Changes in the Fatty Acid Composition of M. longissimus dorsi of Lamb during Storage in a High-Oxygen Modified Atmosphere at Different Levels of Dietary Vitamin E Supplementation

The effect of vitamin E supplementation on fatty acid composition during storage of lamb meat packed in a high-oxygen modified atmosphere was studied. Lambs were fed with diets supplemented with four levels of vitamin E (0, 250, 500, and 1000 mg acetate-alpha-tocopherol/kg feed). Slices of M. longissimus dorsi were packed in a high-oxygen modified atmosphere (70% O2:30% CO2) and stored at 2 +/- 1 degrees C in the dark for 14, 21, and 28 days. The nonsupplemented group (E0) showed an increase in saturated fatty acids (SFA) and monounsaturated fatty acids and a reduction in polyunsaturated fatty acids (PUFA) in total fatty acids. The proportion of SFA and PUFA was unchanged in the supplemented groups (E250, E500, and E1000). The supplementation with 250 mg acetate-alpha-tocopherol/kg feed prevented the oxidation of PUFA in the total lipids and in the polar lipids fraction, while 500 mg acetate-alpha-tocopherol/kg feed was necessary to prevent the oxidation of PUFA in free fatty acids. Supplementing vitamin E not only inhibited lipid oxidation but also maintained nutritional value [essential fatty acids, linoleic acid (C18:2n-6) and linolenic acid (C18:3n-3), and beneficial fatty acids, eicosapentaenoic acid (C20:5n-3) and docosahexaenoic acid (C22:6n-3)] throughout the storage period.

Protective effect of the oligomeric acylphloroglucinols from Myrtus communis on cholesterol and human low density lipoprotein oxidation

Myrtle ( Myrtus communis L.), a culinary spice and flavouring agent for alcoholic beverages widespread in the Mediterranean area and especially in Sardinia, contains the structurally unique oligomeric non-prenylated acylphloroglucinols, semimyrtucommulone and myrtucommulone A, whose antioxidant activity was investigated during the oxidative modification of lipid molecules implicated in the onset of cardiovascular diseases. Both acylphloroglucinols showed powerful antioxidant properties during the thermal (140 °C), solvent-free degradation of cholesterol. Moreover, the pre-treatment with semimyrtucommulone and myrtucommulone A significantly preserved LDL from oxidative damage induced by Cu 2+ ions at 2 h of oxidation, and showed remarkable protective effect on the reduction of polyunsaturated fatty acids and cholesterol, inhibiting the increase of their oxidative products (conjugated dienes fatty acids hydroperoxides, 7β-hydroxycholesterol, and 7-ketocholesterol). Taking into account the widespread culinary use of myrtle leaves, the results of the present work qualify the natural compounds semimyrtucommulone and myrtucommulone A as interesting dietary antioxidants with potential antiatherogenicity.

Effect of black tea, garlic and onion on corn oil stability and fatty acid composition under accelerated oxidation

SummaryFresh black tea, garlic bulbs and onion skin were macerated in refined corn oil to evaluate their antioxidant properties and the effect of heat on oil stability and fatty acid composition in accelerated oxidation experiments at 55 ° and 140 °C. At the lowest temperature control and onion treatments showed an induction time of 3 days with maximum peroxide values of 62 and 45 meq kg−1, respectively. Addition of black tea and garlic increased oil stability with peroxide values of 5 meq kg−1, without appreciable changes in the fatty acid composition. Heating at 140 °C for 48 h produced an accelerated deterioration of corn oil in all treatments. A reduction of polyunsaturated fatty acids of about 40% was observed, with high concentrations of non‐eluted materials which contained thermo‐oxidized substances. It was found that natural extract of black tea and garlic were effective to preserve corn oil under accelerated oxidation at 55 °C which simulates oil behaviour during storage, but cannot reduce the rate of oxidation at frying temperatures.

Free radicals don’t freeze: why red cell membrane phospholipids stored at low temperatures from schizophrenic patients show increased peroxidation

This brief review was stimulated by the finding [1] that in vitro storage of red cell membranes from schizophrenic patients is accompanied by greatly increased loss of unsaturated fatty acids presumably by peroxidation compared to control subjects stored at the same temperature and over the same time period. For highly unsaturated fatty acids such as arachidonic stored at o 70 C the linear loss over time for schizophrenia is twice that of controls. When storage at 20 C and 70 C was compared in control subjects there was no significant difference. However, when phospholipids in membranes from schizophrenic subjects were compared at 20 C and 70 C there was an approximately 50% reduction in polyunsaturated fatty acids at 20 C in the schizophrenic patients compared with 70 C. While it had been well recognised that phospholipids in membranes were subject to storage losses unless kept below 70 C, it had not been realised until now that there was a differential effect between schizophrenic patients and controls over a range of temperatures. What is the cause of these differential storage effects? In prior studies the activity of cPLA2 was found to be increased in schizophrenic patients [2], making it possible that the loss of unsaturated fatty acids in samples stored from schizophrenic patients compared to controls might be linked to the increased activity of cPLA2 prior to freezing. Many other causes of increased peroxidation of fatty acids in schizophrenic patients have been suggested. Would the free radical reaction once started continue at low temperatures? If a free radical chain reaction was to continue then our findings of increased lipid peroxidation in vitro in red blood cell membranes from schizophrenic patients

Free radicals don?t freeze: why red cell membrane phospholipids stored at low temperatures from schizophrenic patients show increased peroxidation*1

This brief review was stimulated by the finding [ [1] Fox H. Ross B.M. Tocher D. Glen I. St Clair D. Degradation of specific polyunsaturated fatty acids in red blood cells stored at −20°C precedes faster in patients with schizophrenia compared to healthy controls. Prostag. Leukot. Essent. Fatty Acids. 2003; 69: 291-297 Abstract Full Text Full Text PDF PubMed Scopus (21) Google Scholar ] that in vitro storage of red cell membranes from schizophrenic patients is accompanied by greatly increased loss of unsaturated fatty acids presumably by peroxidation compared to control subjects stored at the same temperature and over the same time period. For highly unsaturated fatty acids such as arachidonic stored at <−70°C the linear loss over time for schizophrenia is twice that of controls. When storage at −20°C and −70°C was compared in control subjects there was no significant difference. However, when phospholipids in membranes from schizophrenic subjects were compared at −20°C and −70°C there was an approximately 50% reduction in polyunsaturated fatty acids at −20°C in the schizophrenic patients compared with −70°C. While it had been well recognised that phospholipids in membranes were subject to storage losses unless kept below −70°C, it had not been realised until now that there was a differential effect between schizophrenic patients and controls over a range of temperatures.

COMPARISON OF THE FRYING STABILITY OF REGULAR AND LOW‐LINOLENIC ACID SOYBEAN OILS

ABSTRACT The frying stability of a regular soybean oil (RSO) was compared with a modified low linolenic‐acid soybean oil (LLSO). The rate of free fatty acid (FFA) formation was similar for both oils during 72 h of frying. Despite a reduction in polyunsaturated fatty acids, however, the rate of formation of total polar compounds (TPC) in LLSO was greater than RSO. The higher production of TPCs in LLSO was explained, in part, by a lower level of tocopherols and a more rapid rate of degradation of the main isomers, γ‐ and δ tocopherols. This study points to the limitations of predicting frying stability based solely on fatty acid composition.

Inhibition of rat lipoprotein oxidation after tetradecylthioacetic acid feeding

We have previously shown that tetradecylthioacetic acid (TTA), a sulfur containing saturated fatty acid analogue, inhibits the oxidative modification of human low-density lipoprotein (LDL) in vitro. The oxidative modification of LDL is believed to be a crucial step in the progression of atherosclerosis. In the present study, we investigated the effect of TTA oral administration on the susceptibility of rat lipoprotein to undergo oxidative modification ex vivo. Lipoprotein resistance to copper-induced oxidation was highly improved after TTA administration to rats. Conjugated dienes produced after 150 min of lipoprotein oxidation were dramatically lowered in the TTA treated rats compared to controls. Malondialdehyde and lipid peroxides production by oxidation was highly limited. These effects were independent of any Vitamin E effects. More than 50% relative reduction in polyunsaturated fatty acids of the n-3 family, and more than 30% relative increase in 18:1n-9 fatty acid in the triacylglycerol (TAG)-rich lipoprotein were observed. TAG-rich lipoprotein lipids of TTA fed rats were decreased with more than 50% reduction in TAG. The data reported in this paper indicate a potent in vivo antioxidant capability of TTA that beside its hypolipidemic effect might be of importance in relation to the development of atherosclerosis.

Isolation and characterization of two distinct forms of liver fatty acid binding protein from the rat

Liver fatty acid binding protein (L-FABP) appears to contain several different forms that may result from post-translational modification or bound ligand. To further assess this possibility, L-FABP was purified from rat liver homogenate and two putative isoforms separated using a sulfonyl column, a strong cation exchange resin. Fraction I eluted at 0.2 M NaCl, had a p I of 7.59, and following a final size exclusion step contained >98% L-FABP. Fraction II eluted at 1.0 M NaCl, had a p I of 7.59, and following a final size exclusion step contained >99% L-FABP. Both fractions contained approx. 0.15 moles of endogenous bound fatty acid per mole of protein, while L-FABP not subjected to the cation exchange step contained 0.75 moles of fatty acid per mole of protein. Fractions I and II had a greater proportion of saturated and monounsaturated fatty acids with a large reduction in polyunsaturated fatty acids compared to L-FABP not fractionated by cation exchange. Mass spectral analysis indicated the molecular mass of Fraction I was 14 315.02±0.35 Da and Fraction II was 14 315.86±0.34 Da. The peptide map for each fraction was determined by limited digestion of each fraction with either trypsin, Asp-N, or chymotrypsin to yield overlapping peptide fragments. Mass spectral analysis of these digests indicated the two proteins had identical amino acid fragments and that Cys 69 was reduced and there were no Asn to Asp exchanges. Hence, these two forms of L-FABP were not isoforms and were not the result of differences in bound fatty acid. It is proposed that these two distinct forms of rat L-FABP were structural conformers based on two alternative folding pathways.

Effects of supplementation with unsaturated fatty acids on plasma and membrane lipid composition and platelet function in patients with cirrhosis and defective aggregation

Background/Aims: Defective platelet aggregation and reduced platelet production of thromboxane A 2, a metabolite of arachidonic acid, are common findings in patients with cirrhosis. We evaluated the effects of dietary supplementation with two combinations of unsaturated fatty acids on platelet function and plasma and membrane fatty acids in patients with liver cirrhosis. Methods: In a double-blind study, 15 patients with cirrhosis and defective aggregation were randomized to receive a 6-week supplementation with gamma-linolenic and linoleic acid (1 g/day of each fatty acid) or with oleic acid and linoleic acid (groups GLA and OA, respectively). Results: Under baseline conditions, patients showed elevated concentrations of monounsaturated fatty acids and a reduction in polyunsaturated fatty acids. The product/precursor ratios for Δ6 and Δ5 desaturases, two key enzymes in the pathway leading to arachidonic acid, were significantly reduced in the group of patients. In the GLA group, a significant increase in the levels of dihomo-gamma-linoleic acid (20:3ω6) was observed in plasma and membranes, together with a parallel decrease in the 20:4 20:3ω6 ratio after supplementation. No significant changes were observed in the OA group. The levels of arachidonic acid did not change significantly in either group of patients. Platelet aggregation to collagen was unchanged in the GLA group, but significantly improved in the OA group. Conclusions: These results show that supplementation with precursors of arachidonic acid is ineffective in elevating plasma or membrane arachidonate levels and does not improve platelet aggregation, suggesting that synthesis of arachidonic acid through the Δ5 desaturase cannot be correspondingly activated or that incorporation/retention of the produced fatty acid into lipids is impaired. The increased platelet aggregation in the OA group is likely to be explained by the effect of oleic acid contained in the diet, the effects of which may have been counteracted by the elevation in 20:3ω6, a source of anti-aggregatory prostanoids, in the GLA group.

Fatty acid composition of microsomal phospholipids in rats fed different oils and antioxidant vitamins supplement

The aim of the study was to examine effects of feeding diets containing different oils and antioxidant vitamins supplementation on the fatty acid composition of hepatic microsomal phospholipids in the rat. Forty-eight male Sprague Dawley rats were fed for 20 days diets containing 15% corn, olive, fish, or hazelnut oil, without or with the addition of β-carotene (30 mg/kg) and dl-α-tocopherylacetate (500 mg/kg), n = 6 per group. Microsomal phospholipids of rats fed corn oil exhibited higher content of linoleic, arachidonic, and docosatetraenoic acids ( P < 0.05). Compared with corn oil (control group), olive oil intake increased palmitic, oleic, and vaccenic acids in phosphatidylcholine and phosphatidylserine + phosphatidylinositol, and vaccenic acid in phosphatidylethanolamine ( P < 0.05). Fish oil intake increased the level of n-3 long-chain polyunsaturated fatty acids, and decreased arachidonic acid in all phospholipids ( P < 0.05). On the other hand, the intake of hazelnut oil increased palmitoleic and oleic acids in phosphatidylcholine and phosphatidylethanolamine, and palmitoleic and vaccenic acids in phosphatidylserine + phosphatidylinositol ( P < 0.05). Vitamin supplementation increased microsomal retinol in rats fed corn oil, and α-tocopherol in all groups fed vegetable oils ( P < 0.05). The intake of vitamins supplement induced slight modifications of the fatty acid profile of microsomal phospholipids: a higher level of monounsaturated fatty acids, mainly oleic acid, with a reduction of polyunsaturated fatty acids was observed. These results manifest that the composition of microsomes is affected by the fatty acid profile of dietary oils and the intake of antioxidant vitamins supplements.

Effects of hypolipidemic drugs on hepatic degradation of apolipoprotein B and production of apo B-containing lipoproteins

Applicability of the gas chromatography-electron impact-mass spectrometry and data system (GC-EI-MS) for fatty acid analysis of formalin-fixed human tissues was evaluated by comparison of formalin-fixed and unfixed brain tissues, and the results of GC-EI-MS analyses of the formalin-fixed brain and adrenal cortex from cases with adrenoleukodystrophy (ALD) and the cerebro-hepato-renal syndrome of Zellweger (ZWS) were presented. When formalin-fixed and unfixed materials were compared, a reduction of polyunsaturated fatty acids was observed after formalin fixation, while saturated and monounsaturated fatty acids remained unchanged. The chromatographic patterns of brain tissues fixed in 10% formalin for 3 days or 17 months were basically the same. In ALD, increased C26:0C22:0 ratios in the cerebral white matter (2.05 in ALD versus 0.74 in control) and in the adrenal gland (15.2 in ALD versus 0.1 in control), and the presence of unusual very long chain fatty acids (VLCFA), longer than C29 : 0, were demonstrated. In the ZWS brain, all of the VLCFAs were severely depleted. Thus, formalin-fixed tissue may be a reliable subject to fatty acid analysis.

Influence of Phospholipids on the Development of Oxidized Off Flavors in Cooked Turkey Rolls

ABSTRACTTotal lipid and phospholipid (PL) fractions and their fatty acid profiles were analyzed from the interior and exterior portions of cooked turkey breast rolls. Compositional changes during refrigeration were related to oxidative degradation as measured by the TBA test. Breast tissues contained 2% lipid which remained constant over storage. The PLs constituted 0.7% of the meat and only those PLs in the exterior portion degraded during storage. TBA values increased in both roll portions with a concomitant reduction in polyunsaturated fatty acids (PUFAs) having four or more double bonds. These findings suggested that PUFAs were associated with oxidized off‐flavors in cooked turkey rolls. Phosphatidylcholine was present in the highest concentration and underwent the greatest oxidative deterioration.

Effectiveness of orthotopic liver transplantation on the restoration of cholesterol metabolism in patients with end-stage liver disease

The effects of end-stage liver disease and orthotopic liver transplantation on components that modulate cholesterol esterification in plasma were assessed. In comparison with healthy controls, patients with end-stage liver disease had significantly decreased concentrations of lecithin-cholesterol acyltransferase mass, apolipoprotein A-1, total phospholipids, and both total and esterified cholesterol. Elevated phosphatidylcholine and reduced lysophosphatidylcholine fractions indicated impairment of cholesterol esterification by lecithin-cholesterol acyltransferase. Constituent fatty acids of the patients' phospholipids and cholesterol esters manifested increased saturation and a concomitant reduction of polyunsaturated fatty acids, indicative of impaired hepatic elongation and desaturation of essential fatty acids. By the third month after hepatic replacement, the plasma concentrations of total cholesterol, phospholipids, lecithin-cholesterol acyltransferase, and apolipoprotein A-1 were comparable to those of the healthy subjects. Despite the improvement in cholesterol esterification and the rapid normalization of the enzyme and cofactor involved in this process, the percentage of phosphatidylcholine remained significantly higher and the percentages of lysophosphatidylcholine and esterified cholesterol remained significantly lower than in the healthy subjects at 6 mo. Phospholipid and cholesterol ester fatty acid patterns attained normalcy by the sixth month after transplant. We conclude that hepatic transplantation effectively restores cholesterol and essential fatty acid metabolism in patients with end-stage liver disease.

The hydrogenation of phospholipid-bound unsaturated fatty acids by a homogeneous, water-soluble, palladium catalyst

The hydrogenation of unsaturated phospholipids by palladium di(sodium alizarine monosulphonate) activated for 5 min under H 2 proceeded rapidly at 20° C and 1 atm. H 2. Multibilayer liposomes of dioleoyl- and dilinolenoylphosphatidylcholine were hydrogenated at similar rates while dilinoleoyl- and 1-palmitoyl-2-oleoylphosphatidylcholine were hydrogenated at slightly slower rates. The reduction of polyunsaturated fatty acids gave rise to a variety of natural and unnatural positional cis and trans isomers which were largely reduced further to saturated fatty acids as the hydrogenation continued. Dioleoylphosphatidylethanolamine was attacked by the catalyst more slowly at 20° C than was the equivalent phosphatidylcholine molecular species. Experiments conducted using mixtures of phosphatidylethanolamine and phosphatidylcholine in varying proportions also suggested that phospholipids are slightly more susceptible to catalytic hydrogenation in the bilayer phase than in the hexagonal II phase. Understanding the sequence of hydrogenation reactions involving these one and two component lipid preparations is useful in interpreting the action of the palladium catalyst on living cells under the same mild conditions.

Gas chromatography-electron impact-mass spectrometry (GC-EI-MS) analysis of saturated fatty acid compositions in formalin-fixed human tissues

Applicability of the gas chromatography-electron impact-mass spectrometry and data system (GC-EI-MS) for fatty acid analysis of formalin-fixed human tissues was evaluated by comparison of formalin-fixed and unfixed brain tissues, and the results of GC-EI-MS analyses of the formalin-fixed brain and adrenal cortex from cases with adrenoleukodystrophy (ALD) and the cerebro-hepato-renal syndrome of Zellweger (ZWS) were presented. When formalin-fixed and unfixed materials were compared, a reduction of polyunsaturated fatty acids was observed after formalin fixation, while saturated and monounsaturated fatty acids remained unchanged. The chromatographic patterns of brain tissues fixed in 10% formalin for 3 days or 17 months were basically the same. In ALD, increased C26:0 C22:0 ratios in the cerebral white matter (2.05 in ALD versus 0.74 in control) and in the adrenal gland (15.2 in ALD versus 0.1 in control), and the presence of unusual very long chain fatty acids (VLCFA), longer than C29 : 0, were demonstrated. In the ZWS brain, all of the VLCFAs were severely depleted. Thus, formalin-fixed tissue may be a reliable subject to fatty acid analysis.