Ethanolamine Phosphatides Research Articles

Quantitative analysis of porcine spermatozoa and seminal plasma phospholipids as affected by frequency of ejaculation.

Summary. Sixty-four ejaculates were collected from four crossbred litter-mate boars. Two frequencies of ejaculation were employed; once every 3 days and daily. Total semen volume (ml) and total spermatozoa per ejaculate (\m=x\109) for the two frequencies were 157, 37\m=.\4; and 131\m=.\9, 19\m=.\7,respectively. Spermatozoa and seminal plasma phospholipids were determined by thin-layer chromatography and phosphorus analysis. The phospholipid components of spermatozoa, in order of decreasing concentration, were: choline phosphatides, ethanolamine phosphatides, sphingomyelin, serine phosphatides, phosphatidic acid and/or polyglycerol phosphatides. Differences between collection frequencies for the phospholipid components were not significant. The seminal plasma phospholipid contained the same component phospholipids as the spermatozoa in addition to trace quantities of lysolecithin. Sphingomyelin was the major phospholipid present in the seminal plasma.

Interrelationships among the ethanolamine phosphatides in myelinating rat brain.

Abstract— —The ethanolamine phosphatide fraction was isolated from rat brain at 17, 19, and 22 days of age. Analysis by gas‐liquid chromatography of the liberated fatty aldehydes and alkyl glyceryl ethers demonstrated a chain length composition quite distinct from that of the fatty acids in the comparable 1(3)‐position of the diacyl phosphatides. [1‐14C]‐Acetate was administered intraperitoneally to 17‐day‐old rats. With the exception of the polyunsaturated fatty acids, isotope was readily incorporated into the individual side chains of the 1‐ and 2‐positions of the glycerol moiety. Time studies revealed no readily discernible precursor‐product relationships among the linkages in question. Therefore, although the long chain precursors for the alkenyl and alkyl ethers may be related by biosynthetic interconversion, the isotope data are suggestive of independent pathways of biosynthesis for the alkenyl ether, alkyl ether, and ester linkages.

The structure of human density lipoprotein: A study of the effect of phospholipase A and trypsin on its components and of the behavior of the lipid and protein moieties at the air-water interphase

1. 1. The accessibility of the protein and lipid components of human high density lipoprotein with density between 1.064 and 1.210 g/ml (HDL) to trypsin and phospholipase A (phosphatide acyl-hydrolase) was evaluated in an effort to explore the surface structure of the lipoprotein particle. 2. 2. Results obtained by gel filtration and peptide mapping of the trypsin digests of HDL and the lipid-free protein component of HDL (apo-HDL) suggest that extensive regions of the HDL-protein in the lipoprotein particle are as accessible to trypsin as related regions in the lipid-free apo-HDL. 3. 3. Phospholipase A affected more than 95% of the choline and ethanolamine phosphatides of HDL without causing disruption of the lipoprotein. 4. 4. Apo-HDL obtained by lipid extraction of HDL showed an appreciable surface activity at the air-water interphase. Measurements of the area occupied by apo-HDL and HDL-lipids at this interphase suggest that in the HDL particle the lipid and protein components are oriented at the surface of a structure in which the polar regions of lipids and the protein are exposed to the aqueous environment.

Essential Fatty Acid Deficiency and the Testis: Lipid Composition and the Effect of Preweaning Diet

These experiments were designed to characterize the lipid changes in the rat testis as essential fatty acid (EFA) deficiency progresses and to relate these to the gross and histological state of the tissue. Also, information was sought as to why reports of testis damage in EFA deficiency have been conflicting. It was found that predepletion by feeding an EFA-deficient diet 11 days before weaning resulted in testis damage in 6 to 9 weeks compared with more than 16 weeks in rats fed the diet after weaning. Three percent of saturated fat did not accelerate EFA deficiency compared with a fat-free diet. Analyses of testes for total lipid, total phospholipid, phospholipid classes, total fatty acids and fatty acids in the choline and ethanolamine phosphatides after 6 and 9 weeks of EFA deficiency did not reveal any changes which could be correlated with the onset of histological damage. The testis appears to be particularly sensitive to EFA deficiency during the developmental period, but if maturation occurs, then a prolonged period of deficiency is required before damage appears. The results suggest that secondary effects of EFA deficiency are responsible for eventual testis degeneration.

The ALK- i-enyl ether and alkyl ether lipids of bovine heart muscle

Choline phosphatides and ethanolamine phosphatides as well as neutral alkoxylipids and triglycerides were isolated from a lipid extract of bovine heart muscle. The constituent alk- i-enyl glycerol ethers, alkyl glycerol ethers and fatty acids of these lipid classes were analyzed after selective acidic or enzymatic hydrolysis. Comparative analyses of the aliphatic moieties at the 1 and 2 positions of the phosphatides revealed a pronounced similarity of the three classes of choline phosphatides, whereas significant differences between the various ethanolamine phosphatides were encountered. Alk- i-enyl diglycerides and alkyl diglycerides differed in the composition of their aliphatic moieties from each other, from the triglycerides and from the phosphatides.

Distribution of Fatty Acids in Cod Flesh Lipids

Cod flesh lipids were separated by silicic acid chromatography into eight fractions, and the fatty acid distribution in five of these was examined by gas–liquid chromatography (GLC). As compared with the fatty acid composition of total flesh lipids, sterol esters contained less 16:0 but more 20:5ω3; ethanolamine phosphatides contained less 16:0, less 20:5ω3, but more 22:6ω3; serine phosphatides contained less 16:0 and less 20:5ω3 but more 18:0; and choline phosphatides had a fatty acid composition roughly similar to that of total flesh lipid but containing slightly more 16:0 and 20:5ω3 and less 22:6ω3. In fatty acid composition, the triglycerides more closely resembled liver lipid than any of the flesh lipid fractions.

The turnover of myelin in the adult rat

The rate of loss of radioactivity of lipids of brain subcellular fractions was followed for 56 days after injection of adult rats with uniformly labeled [ 14C]glucose. Myelin did not reach its maximum specific activity until 5 days after injection, then showed a slow rate of loss of radioactivity. When the turnover of the lipid components of purified myelin was measured, inositol phosphatide and lecithin were found to have a more active metabolism than the other myelin lipids which include serine phosphatide, sphingomyelin, ethanolamine phosphatide, cerebroside, cerebroside sulfate, and cholesterol. These results which agree with our previous findings indicate that the metabolism of myelin on the outer layers is identical to that laid down early in the life of the animal. Proteolipid protein showed a half-life of about 35 days, thus was one of the more active myelin components. The pattern of metabolism, though on a longer time scale in myelin, is similar to that of the most active brain membrane fraction. These results are discussed in relation to the possible structure of myelin membranes.

Lipid monolayers: interactions with the apoprotein of high density plasma lipoprotein

Monolayer techniques were used to study the interactions of various lipids (cholesterol, lysophosphatidyl choline, phosphatidal ethanolamine, phosphatidyl choline, sphingomyelin, stearic acid, and lipids extracted from plasma high density lipoproteins and very low density lipoprotein) with the lipid-free protein subunit of rat plasma high density lipoprotein and with rat plasma albumin. The proteins were injected under the lipid monolayer at fixed area, and the increase in surface pressure (decrease in surface tension) was measured as a function of time. With all lipids, both the rate and magnitude of this increase were greater with the apolipoprotein than with albumin. The degree of film penetration of pure lipid films (at an initial film pressure of 15 dynes/cm) by the two proteins followed the same order: cholesterol > phosphatidal ethanolamine > phosphatidyl choline > stearic acid > sphingomyelin > lysophosphatidyl choline. Other variables studied were protein concentration, initial film pressure, and pH. Two distinctive properties of the apolipoprotein were the penetration of lipid films at pressures above the collapse pressure of the protein, and the formation of a film even at low salt concentration. High surface activity and strong interaction of HDL-protein with lipid monolayers may be associated with the flexibility of the protein molecule due to absence of disulfide bridges. The unusual surface activity of HDL-protein may be intimately related to the mechanism of formation of the lipoprotein.

Metabolism of chimyl alcohol and phosphatidyl ethanolamine in the rat brain

Following intracerebral injection of(14)C-phosphatidylethanolamine and(3)H-chimyl alcohol into 18 day old rats, the ethanolamine phosphoglycerides were isolated and analyzed. The(14)C and(3)H activities in the dimethyl acetals derived from alkenyl acyl ethanolamine phosphoglycerides and in the glyceryl ethers derived from the alkyl acyl ethanolamine phosphoglycerides were measured. The absence of(14)C in the dimethyl acetals indicates that phosphatidyl ethanolamine is not transformed into phosphatidal ethanolamine under these circumstances. The increase with time of the(3)H content of the glyceryl ethers and dimethyl acetals indicates that chimyl alcohol was a precursor of both types of phospholipids.

Quantitative determination of phosphatidal ethanolamine and other phosphatides in various tissues of the rat

A method based on thin-layer chromatography was devised for the determination of microgram quantities of the phospholipids. This procedure was used to estimate both the quantity and the radioactivity of the ethanolamine plasmalogens by taking advantage of the fact that the α,β-unsaturated ether bond of these compounds is hydrolyzed in the presence of mercury salts. The conditions of this reaction were investigated to ensure that complete hydrolysis took place and that the ester phospholipids were not affected. Under these conditions, estimation of the lysophosphatidyl ethanolamine produced permitted accurate quantitation of the phosphatidal ethanolamine in the lipid mixture. With this method values were obtained for the phosphatide composition of whole rat brain, and the phosphatidal ethanolamine content of a number of other tissues. The assay procedure can also be applied to other chromatographic systems.

The phospholipids of various sheep organs, rat liver and of their subcellular fractions

The phospholipid compositions of sheep liver, brain, kidney, spleen, heart, and adrenal gland and rat liver, as well as of subcellular organelles derived from some of these tissues, have been examined. Microsomes of all tissues are richest in phospholipid. Relatively little phospholipid was found in the cell sap of liver, brain, kidney and adrenal. Lecithin was the predominant phospholipid in all tissues and subcellular organelles examined. All tissues, with the exception of the liver contain substantial amounts of plasmalogen, which was mainly ethanolamine plasmalogen. In the heart, however, choline plasmalogen predominated. The mitochondria of all tissues contained relatively more ethanolamine phosphatide than was found in other subcellular sites. Most striking was the high concentration of polyglycerolphosphatide found only in the mitochondria. Despite this observation it is not quite certain that the mitochondria contain the entire cell complement of polyglycerolphosphatide. Evidence has been presented that purified nuclear preparations may contain significant amounts of this latter lipid. The relationship of this lipid to electron transport in mitochondria is discussed.

On the possibility of lysophosphatide formation during Wallerian degeneration.

Abstract—During an extensive decomposition of phospholipids, at the end of the second week of Wallerian degeneration, the decomposition of glycerophosphatides were studied in detail. In a degenerative process lasting for 2 weeks about one‐third of the choline phosphatides, two‐thirds of the ethanolamine phosphatides, one‐third of the serine phosphatides and one‐quarter of the inositol phosphatides, were destroyed.The amount of lysophosphatidylcholine decreased proportionally to the destruction of choline phosphatide. On the other hand, the amount of lysophosphatides formed from‘kephalin'‐containing fatty aldehyde, during the marked destruction of these phospholipids, remained constant or increased to a small extent and its percentage distribution increased 2 or 3 times compared with other phospholipids. Ethanolamine phosphatides having a high fatty aldehyde content can be regarded as mainly responsible for the relative accumulation of lysophosphatides.

Molecular Composition of Myelin Synthesized Subsequent to Irradiation

Myelin has been isolated from brain stems of control rats and their head-irradiated littermates (700 rads at 2 days of age). Rats were sacrificed at 20, 30, 40, and 180 days of age. Much less myelin was found to be deposited in brain stems of head-irradiated rats as compared to controls. However, within experimental error, no differences were ascertained, as functions of either age or irradiation, in major building blocks of myelin. These include total protein, total sterol, phosphatidyl serine, sphingomyelin, phosphatidyl choline + lyso-phosphatidyl choline, phosphatidyl ethanolamine + phosphatidal ethanolamine, and cerebroside + cerebroside sulfate. However, the proportions of all normal unsaturated fatty acids in myelin from irradiated rats were lower with respect to their saturated counterparts than in control myelin. Markedly lower ratios of both monounsaturated C24 acid and monounsaturated C26 fatty acid to their saturated counterparts were noted, and the proportion of total C26 to total C24 fatty a...

The condensation of long-chain aldehydes to 2,3-dialkylacroleins in the presence of ethanolamine phosphatides.

The condensation of long-chain aldehydes to 2,3-dialkylacroleins in the presence of ethanolamine phosphatides.

Chromatographic separation of plasmalogenic, alkyl-acyl, and diacyl forms of ethanolamine glycerophosphatides

The plasmalogenic, alkyl-acyl, and diacyl forms of ethanolamine glycerophosphatides were completely separated from each other as methylated dinitrophenyl derivatives by thin-layer chromatography on Silica Gel G. The relatively high resolving power needed was obtained by multiple unidimensional development with solvents that give very low mobility to the lipids. Under these conditions the plasmalogens moved fastest, the alkyl-acyl lipids were intermediate, and the diacyl lipids were the slowest. The presence of all these forms of lipids in the ethanolamine phosphatides of hen's eggs, ox brain, and human blood plasma could be directly demonstrated with the new method.

Mono- and dimethyl phosphatidates from different subtypes of choline and ethanolamine glycerophosphatides

Preparation and some properties of phosphatidic acids and their mono- and dimethyl esters from natural phosphatides were studied. 1. 1. Hydrolysis with cabbage phospholipase D (EC 3.1.4.4) converted all three subclasses of ox heart lecithin, viz. phosphatidyl choline, choline plasmalogen and alkyl acyl lecithin, into phosphatidic acids. Phospholipase D catalysed methanolysis converted phosphatidyl choline to phosphatidyl methanol. The same reaction appeared to take place also with choline plasmalogens and alkyl acyl lecithins. The hydrolysis, and quite likely also the methanolysis, was a fast reaction with phosphatidyl cholines and alkyl acyl lecithins but very slow with the plasmalogens. 2. 2. The three subclasses of phosphatidic acid, the diacyl, the plasmalogenic, and the alkyl acyl forms, were completely separated from each other by thin-layer chromatography of the dimethyl esters. 3. 3. The Chromatographie properties of phosphatidic acid were shown to depend on the cations present ; the Ca 2+ salt was not retained by DEAE-cellulose or alumina from neutral solvents, but the Na + salt was retained appreciably. Also on silicic acid columns these two salts gave remarkably different elution patterns. The behaviour of phosphatidyl methanol on DEAE-cellulose was affected much less than that of phosphatidic acid by the presence of Ca 2+. 4. 4. Diazomethanolysis converted all three subclasses of ox heart lecithin into the corresponding dimethyl phosphatidates. Phosphatidyl cholines and alkyl acyl lecithins seemed to react without complication, but choline plasmalogens gave an unidentified product in addition to the dimethyl phosphatidate. Diazomethanolysis of the same three subtypes present in ox brain ethanolamine phosphatides also gave the different dimethyl phosphatidates. 5. 5. The more polar products formed in the diazomethanolysis of the lecithins and ethanolamine lipids appeared to contain phosphatidyl methanol and O-methylated lecithins and chephalins, which are probably intermediate products of the reaction. 6. 6. The dimethyl phosphatidates could be effectively separated into different molecular species by argentation chromatography. The positional analysis of fatty acids in these lipids could be carried out with pancreatic lipase which attacks preferentially the ester groups on C-1 of glycerol. The plasmalogenic dimethyl phosphatidates and their alkyl analogs were virtually stable towards this enzyme. 7. 7. NMR spectra of phosphatidic acid and its mono- and dimethyl esters were recorded.

Fractionation of a natural mixture of alkenyl acyl and diacyl ethanolamine phosphatides by argentation adsorptioin thin-layer chromatography

Abstract Argentation adsorption thin-layer chromatography has been used for the fractionation of a natural mixture of alkenyl acyl- and diacyl choline phosphatides. This produced not only concentrates of alkenyl acyl choline phosphatides but also species of alkenyl acyl- and diacyl choline phosphatides that varied in unsaturation in the fatty acid moieties.

Phospholipids of bovine spermatozoa and seminal plasma.

Summary. Spermatozoal and seminal plasma lipids of fourteen individual bulls were separated by column chromatography into neutral lipid and several phospholipid fractions. Elution progress was monitored by thin-layer chromatography. Each phospholipid constituent was determined by phosphorus analysis. Total lipid, cholesterol and plasmalogen contents were determined. The fatty acids and aldehydes of the choline and ethanolamine phosphatide fractions were analysed by gasliquid chromatography. The spermatozoal phospholipid comprised 35·6% phosphatidyl choline, 28% phosphatidal choline, 20% phosphatidyl ethanolamine, 7·2% phosphatidal ethanolamine and 9·1% sphingomyelin. The seminal plasma phospholipid comprised 30% phosphatidyl choline, 23·6% phosphatidal choline, 10·5% phosphatidyl ethanolamine, 16·3% phosphatidal ethanolamine, 14·1% sphingomyelin and 5·4% polyglycerol phosphatide. Myristaldehyde and palmitaldehyde were the only aldehydes identified in the choline and ethanolamine phosphatide fractions. Docosahexaenoic acid constituted a large portion of the fatty acids of spermatozoal choline phosphatide.

Lipids of human leukocytes: relation to cell type

Significant differences in lipid composition have been found between normal human lymphocytes and polymorphonuclear leukocytes (isolated from blood by means of glass-bead columns), abnormal leukocytes from patients with acute and chronic leukemia, and leukocytes from peritoneal exudates. Lipid extracts of isolated leukocytes were analyzed for total lipid, phosphorus, cholesterol, and plasmalogens. Individual phospholipids and neutral lipids were separated by thin-layer chromatography. The major phospholipids were phosphatidyl choline, ethanolamine glycerophosphatides, sphingomyelin, phosphatidyl serine, and phosphatidyl inositol. Plasmalogen was found mainly as phosphatidal ethanolamine. The neutral lipid fractions contained free cholesterol and various amounts of triglyceride, but little esterified cholesterol. Normal lymphocytes contained about half as much total lipid per cell as normal polymorphonuclear leukocytes, with a similar cholesterol:-lipid-P ratio but relatively more lecithin and less ethanolamine glycerophosphatide. Normal mature leukocytes, compared with immature cells of the same morphological series, had a higher total lipid content per cell, more cholesterol, and a higher ratio of cholesterol to lipid-P. Little difference was found in total lipid-P per cell, but mature cells contained relatively less lecithin and more sphingomyelin. These findings may reflect differences in the relative content of various intracellular organelles as well as possible differences in the quantity and composition of the plasma membrane.

The biosynthesis of glycerides and glycerophosphatides by rabbit reticulocytes

1. 1. When rabbit reticulocytes were incubated with [1- 14C]glycerol, radioactivity was incorporated into glycerides and glycerophosphatides but no radioactivity was present in their fatty acid moieties or in cholesterol. 2. 2. Lecithin and ethanolamine phosphatide together contained about 70% and the neutral lipids about 20% of the total radioactivity. The triglyceride, which comprised less than 2% of the lipids, had the highest specific activity of all the lipids. 3. 3. Experiments with other radioactive precursors of the phosphatides gave results which indicate that the minor phosphatides are metabolically much less active than lecithin and that the formation of lecithin from serine phosphatide or ethanol-amine phosphatide is quantitatively unimportant in these cells. 4. 4. Incubation of rabbit reticulocytes with [2- 3H]inositol resulted in the formation of radioactive phosphoinositides. Most of this radioactivity was present in a monophosphoinositide.