Effect of Retinol on Liver Lipid Metabolism of Rats

Effect of feeding 4.23, 16.94 and 27.53 mg of retinol daily for 10 days on the liver lipids of adult rats has been studied. Feeding of different amounts of retinol produced dose dependent toxicity symptoms in rats. Retinol feeding resulted in significant elevations of liver total lipids, total fatty acids, and glycerides, The amounts of liver esterified cholesterol were significantly raised in rats fed different amounts of retinol. Acetate-1-¹⁴C incorporation was increased in liver total cholesterol of rats fed 27.53 mg retinol and in free cholesterol of all retinol fed rats. Total ¹⁴C activity of hepatic triglycerides of retinol fed rats was the same as that of control, but their specific activity was decreased. Significant alterations were noted in phosphatidyl serine, lysophosphatidyl choline, lysophosphatidyl ethanolamine, sphingomyelin, phosphatidyl choline, phosphatidyl ethanolamine and phosphatidic acid and polyglycerophosphate fractions in liver rats fed different amounts of retinol.     

Hormonal influence on testicular lipids.

The effects of progesterone and progesterone plus oestrogen (PPO) on testicular lipids of adult rats were studied. Treatment with progesterone over 7 days did not alter significantly the total lipids, cholesterol, glycerides and phospholipids. However, PPO administration brought about a significant elevation in total lipids, mainly contributed by the increase in triglycerides. The phospholipids and total cholesterol were not markedly affected by PPO treatment, but the individual classes of phospholipids showed marked alterations in their pattern of distribution. The esterified and free cholesterol fractions were found to be significantly altered by both the treatments. Progesterone appears to favour ester cholesterol accumulation by depleting the available free cholesterol. Oestrogen seems to increase the glycerides and change the concentration of phosphatidyl serine, phosphatidyl choline and phosphatidyl ethanolamine when administered with progesterone.     

Lipids of a T Strain of Mycoplasma

Cholesterol, free fatty acids, and phosphatidic acid are the predominant lipids of a T strain of Mycoplasma. The remaining neutral lipids are composed of cholesteryl esters, triglycerides, and diglycerides. Three glucose-containing glycolipids are present in trace amounts. In addition to phosphatidic acid, the phospholipids are comprised of phosphatidyl glycerol, diphosphatidyl glycerol, and phosphatidyl ethanolamine. Another polar lipid was found to be ninhydrin-positive and phosphate-free. It appears to be a diamino hydroxy compound containing adjacent fatty acid ester and N-acyl groups.     

Change in the Triglyceride Level in Sea Urchin Eggs and Embryos During Early Development

Triglycerides in the embryos of the sea urchin, Anthocidaris crassispina , analyzed by gas-liquid chromatography, distributed in a range of carbon numbers between 42 and 58 in the sum of three fatty acid residues. During the development until gastrulation, the levels of triglycerides with 48, 56 and 58 carbon numbers decreased at constant rates and the levels of the others decreased at specific stages different with one another, respectively. Thereafter, the amounts of all triglycerides decreased simultaneously. The amount of oxygen consumed in the embryos is enough for the oxidation of mobilized triglycerides during post-hatching period but is not during pre-hatching period. The levels of neutral glycerides increased gradually during pre-hatching period and thereafter decreased. The fatty acid level also increased during pre-hatching and post-hatching period. These suggest that the cleavage of triglycerides and the oxidation of their cleavage-products occur during whole span of early development. During pre-hatching period, the break down of triglycerides is probably higher in its rate than the rate of their oxidation, resulting in the increase in the levels of neutral glycerides, as well as fatty acids.     

Die Lipide von Endomycopsis vernalis bei verschiedener Stickstoff-Ernährung

1. Endomycopsis vernalis was cultivated on media with different N supply: series A 1%, series B 0,125% asparagine. Sonified cells were extracted and yielded 14.3% (A) and 65.3 (B) total lipids/non lipid dry matter respectively.
2. Neutral and complex lipids were separated by rubber membrane dialysis. There is no difference in the percentage of complex lipids of both series. The increase of lipids in cells grown on low N level is due to a higher content of neutral lipids.
3. Components of the neutral lipids, analysed by DC, were diglycerides, triglycerides, free and esterified ergosterol. Their percentage is influenced by the nutritional conditions. There is a significant increase of triglycerides and of sterol esters in the high lipid cells of series B.
4. Methyl esters of component fatty acids of glycerides and sterol esters were analyzed by GLC. Saturated acids C₁₄, C₁₅, C₁₆, C₁₇, C₁₈, monoenic acids C₁₆ and C₁₈, linoleic and linolenic acids were found to be present. Major acids were in all cases 18:1 (17–57%), 18:2 (18–50%) and 16:0 (10–18%). Linolenic acid is higher in di-and triglycerides of low lipid cells of series A than in high lipid cells of series B. Both qualitative and quantitative differences of fatty acids were found in sterol esters of series A and B respectively.
5. The major components of complex lipids, identified by DC and isolated by CC, in both series, were phosphatidyl choline (A:36.5, B:41.0%) and phosphatidyl ethanolamine (A:24.9, B:20.5%) in addition to small amounts of lysophosphatidyl choline, lysophosphatidyl ethanolamine, phosphatidyl serine, monophosphoinositide, diphosphatidyl glycerol and, possibly cerebroside like substances.
6. Methyl esters of the fatty acids of phosphatidyl choline and ethanolamine from both series were determined by GLC. In all samples 16:0, 18:0, 18:1, 18:2 and 18:3 acids were present besides of traces of 16:1 and 17:0. In contrast to neutral lipids the major acid of phospholipids is linoleic (53–58%), followed by oleic (8–24%) and linolenic acid (1–18%). The percentages of palmitic (4–8%) and stearic acids (tr.-1%) are small. Low lipid cells of series A differ from high lipid cells of series B by an increase of linolenic, and a decrease of linoleic acids, both in phosphatidyl choline and phosphatidyl ethanolamine.

     

Lipid and sterol composition of the pollen of the west african oilpalm, Elaeis guineensis

The lipid classes, fatty acid methyl esters and the sterols of oilpalm pollen were analysed. The neutral lipid fraction consisted of triglycerides, esterified and free sterols and trace amounts of hydrocarbons. Monogalactosyl and digalactosyl diglycerides, phosphatidyl choline, phosphatidyl inositol and phosphatidyl ethanolamine represented the polar lipids. The major fatty acids were linoleic, palmitic and linolenic acids together with small to trace amounts of oleic, stearic, arachidic, myristic, lauric, palmitoleic and margaric acids. Unsaturated fatty acids predominated over saturated ones in the ratio of 3:2. The 4-desmethyl sterols were the major phytosterols in the free form but they constituted a lower proportion of the sterols in the esterified state. 28-Isofucosterol was isolated and characterized as the principal sterol.     

Composition of lipids of Actinomyces olivaceus--synthesis of vitamin B 12]

Total cellular lipids of the synthetic of vitamin B12 Act. olivaceus involve predominantly phospholipids (about 70%). Lipid phosphates consist of phosphatidyl ethanol amine and phosphatidyl-2,3-butandiol (over 40 and 30%, respectively) and lower quantities of phosphatidyl inositol olmonomanoside and cardiolipin. The neutral fraction includes the predominating fraction of triglycerides (over 20%) as well as mono- and diglycerides, free fatty acids, hydrocarbons and three fractions similar to waxes, sterines and sterine esters in their Rf values.     

Lipids and Lipoprotein Complex in Photosynthetic Tissues

The lipids and pigments of corn and soybean leaves grown in light and in dark were examined. The green leaf contained appreciably greater amounts of the two galactolipids, sulfolipid, phosphatidyl glycerol and diphosphatidyl glycerol, while the etiolated leaf had relatively more cerebroside, sterol glucoside, phosphatidyl ethanolamine and lecithin. The prominent component of glycerides was 1,2-diglyceride in green leaf, and triglyceride in etiolated leaf. The green leaf lipids showed a remarkable specificity of component fatty acids, but those of etiolated leaf only at lower rate. From the results, possible functions of the lipids were discussed.     

Hypervitaminosis A and Liver Phospholipids

Effect of daily oral feeding of 33 mg retinol for nine days on the liver phospholipids of rats has been studied. As early as two days after feeding retinol an increase in the amounts of liver triglycerides, proteins, phospholipids, and cholesterol was noted which kept increasing and reached the peak concentration 6 days after daily retinol feeding and thereafter a decrease in their amounts was noted. Hepatic phospholipid fractions viz. phosphatidyl choline, phosphatidyl ethanolamine, phosphatidic acid and polyglycerol phosphatide, phosphatidyl inositol, phosphatidyl serine, sphingomyelin, lysophosphatidyl ethanolamine and lysophos- phatidyl choline showed the same pattern. Labelling of these phospholipids with NaH₂³²PO₄ in rats fed daily 33 mg of retinol for a period of two days also exhibited the pattern which was observed in their amounts two days after daily feeding of retinol. The results suggest a close relationship between the metabolism of hepatic triglycerides and phospholipids of rats fed excessive amounts of retinol.     

The Triglycerides of Fats from Several Varieties of Sapium sebiferum (L.) Roxb

The triglycerides of fats from several varieties of Sapium sebiferum (L.) Roxb. were determined by means of pancreatic lipase hydrolysis technigue. Triglycerides of the fats. are composed of 9–14 kinds of triglycerides. They are similar to Cocoa butter. Fatty acid composition in 2-position of glycerides is oleic acid in more than 82%. The disaturated glycerides account for 81-88%, in which POP is in the majority (74–81%); the proportion of monosaturated glycerides is 1.8–6.0%; the trisaturated glycerides hold 9.6–15.6%, in which the main one is PPP (8.5–14.0%). The fats can be used for making Cocoa butter substitute by proper processing. Fat contents of the four varieties (“Da Li Ji Zhao”, “Wu Gong”, “Tong Chui” and “Xiao Li Ji Zhao”) cultivated in Guangxi province are richer (32.0–34.3%) than that of the wild species of the same plant. The proportion of disaturated glycerides is the highest (88.0%) and that of trisaturated glycerides is the lowest (9.6%) in fat from "Da Li Ji Zhao".     

Lipids from nerve tissues of the horseshoe crab, Limulus polyphemus.

1. The predominant lipids of nerve cords, ganglion and brain from horseshoe crabs were cholesterol (11% of lipid) and phospholipid (81% of lipid). 2. Major phospholipids were phosphatidyl ethanolamine and phosphatidyl choline with lesser amounts of phosphatidyl serine and phosphatidyl inositol and sphingomyelin. 3. The phospholipid fraction was characterized by a high content of plasmalogen, i.e. alk-1-enyl acyl phosphatides, so that 42% of the ethanolamine phosphatides were the plasmalogen, phosphatidal ethanolamine. 4. Phosphatidyl choline and phosphatidyl ethanolamine were high in polyunsaturation with 20:4 and 20:5 major fatty acids. Sphingomyelin had predominantly long chain saturated fatty acids. 5. Cerebrosides and gangliosides, which are associated with vertebrate nerve tissues, were absent from nerves of horseshoe crabs.     

Aluminum-induced lipid phase separation and membrane fusion does not require the presence of negatively charged phospholipids

The interaction of Aluminum with phosphatidyl serine lipid vesicles containing variable amounts of phosphatidyl ethanolamine, phosphatidyl choline and cholesterol has been studied by lipid phase separation monitored by fluorescence quenching. The interaction of Al3+ with neutral phospholipid membranes has also been investigated. Maximal lipid phase separation can be demonstrated in mixed phosphatidyl ethanolamine-cholesterol vesicles when using concentrations of aluminum between 87.5 and 125 microM. Millimolar concentrations of Ca2+, Mn2+, Cd2+ and Zn2+ were without any effect. Aluminum also induced fusion of phospholipid membranes monitored by resonance energy transfer between N-(7-nitro-2,1,3, benzoxadiazol-4 yl) phosphatidyl ethanolamine and N-(lissamine Rhodamine B-sulfonyl) phosphatidyl ethanolamine, either when containing low amounts of phosphatidyl serine (12.5%) or without any negatively charged phospholipid. Aluminum-induced fusion of liposomes was also monitored by the fluorescence of the terbium-dipicolinic acid complex (Tb-DPA3-) formed during fusion of vesicles containing either Tb-(citrate)6- complex or sodium salt of dipicolinic acid.     

Effect of Feeding Millet (Sorghum vulgarie) Protein at Various Protein Levels on Adrenal Lipids of Rats

A significant increase in adrenal weight, total lipids, cholesterol phospholipids and glycerides (mono-and triglycerides) was observed in rats fed millet at 5, 10 and 15 % protein levels respectively for a period of six weeks as compared to rats fed casein at 10 per cent level. Increases in cholesterol were in both its free and esterified fraction. Adrenal phosphatidyl etha-nolamine was increased in all millet fed rats whereas phosphatidyl choline increased in M–15 % and decreased in M–5 % groups. Other phospholipid fractions viz. monophosphatidyl inositol, lysophosphatidyl ethanolamine, sphingomyeline, phosphatidic acid and polyglycerophosphatide also showed significant alterations in rats fed millet protein as compared to control. Incorporation of acetate–l–¹⁴C into adrenal lipids was lower and that of glucose–U–¹⁴C, palmitate–l–¹⁴C and NaH₂³²PO₄ was higher than the control.     

Utilization of ascites plasma very low density lipoprotein triglycerides by Ehrlich cells

Much of the lipid present in the ascites plasma in which Ehrlich cells grow is contained in very low density lipoproteins (VLDL). Chemical measurements indicated that triglycerides were taken up by the cells during in vitro incubation with ascites VLDL. When tracer amounts of radioactive triolein were incorporated into the ascites VLDL, the percentage uptakes of glyceryl tri[1-(14)C]oleate and triglycerides measured chemically were similar. The cells also took up [2-(3)H]glyceryl trioleate that was added to VLDL, but the percentage of available (3)H recovered in the cell lipids was 30-40% less than that of (1 4)C from glyceryl tri[1-(1 4)C]oleate. This difference was accounted for by water-soluble (3)H that accumulated in the incubation medium, suggesting that extensive hydrolysis accompanied the uptake of VLDL triglycerides. Radioactive fatty acids derived from the VLDL triglycerides were incorporated into cell phospholipids, glycerides, and free fatty acids, and they also were oxidized to CO(2). Triglyceride utilization increased as the VLDL concentration was raised. These results suggest that one function of the ascites plasma VLDL may be to supply fatty acid to the Ehrlich cells and that the availability of fatty acid to this tumor is determined in part by the ascites plasma VLDL concentration. Although Ehrlich cells incorporate almost no free glycerol into triglycerides, considerable amounts of [2-(3)H]glyceryl trioleate radioactivity were recovered in cell triglycerides. This indicates that at least some VLDL triglycerides were taken up intact. The net uptake of VLDL protein and cholesterol was very small relative to the triglyceride uptake, suggesting that intact triglycerides are transferred from the ascites VLDL to the Ehrlich cells and that hydrolysis occurs after the triglyceride is associated with the cells.     

Molecular weight distributions of milk fat triglycerides from seven species

The triglyceride compositions of the milk fats of man, dog, guinea pig, cow, sheep, goat, and horse were compared by gas-liquid chromatography of the intact triglycerides and of the butyl esters of the component fatty acids. The milk fats of man, dog, and guinea pig, which were largely made up of long-chain fatty acids, showed a common pattern with major contributions made by the glycerides with 48-54 acyl carbon atoms. The milk fats of cow, sheep, and goat, which were rich in short-chain acids, showed significant proportions of triglycerides with 28-54 acyl carbon atoms. Horse milk, which contains large amounts of medium-chain fatty acids, gave a characteristic triglyceride pattern in the 26-54 carbon atoms range. The experimentally determined distributions of the molecular weights of the triglycerides of all milk fats deviated significantly from the distributions predicted by random association of the fatty acids from a single pool. The data suggest that in all species the milk fat may be formed by a partial resynthesis of preformed glycerides.     

Lipid profiles of Aspergillus niger and its unsaturated fatty acid auxotroph, UFA2

A comparative study of the mycelial lipid composition of a wild strain (V35) and one unsaturated fatty acid auxotroph (UFA2) of Aspergillus niger has been performed. The lipid composition of both strains are qualitatively the same but quantitatively different. All the strains contain the following phospholipids: cardiolipin, phosphatidylethanolamine, phosphatidylcholine, lysophosphatidylethanolamine, lysophosphatidylcholine, and phosphatidylserine; and triglycerides, diglycerides, monoglycerides, ergosterol, and sterol esters as the neutral lipids; mono- and di-galactosyl diglyceride as the major glycolipids along with small amounts of the corresponding mannose analogs. Phosphatidylethanolamine and phosphatidylcholine constitute the bulk of the phospholipids. The mutant (UFA2) contains a higher level of glycerides and lower levels of sterol (both free and esterified form), phospholipids, and glycolipids than the wild type. Aspergillus niger contains C16 to C18 saturated and unsaturated fatty acids. Small amounts of long-chain (C20 to C24) and short-chain (C10 to C14) saturated and unsaturated acids are also present. Linoleic, oleic, and palmitic are the major acids, stearic and linolenic acids being minor ones. UFA2 grows only in the presence of unsaturated fatty acid (C16 or C18) and accumulates a higher concentration of supplemented acid which influences its fatty acid profile.     

Lipid and Fatty-acid Composition of Diatoms

The lipids and fatty acids of two freshwater diatoms Nitzschiapalea Kutz, Navicula muralis Lewin, and one marine species,Navicula incerta Grun. have been studied. The major lipid components in all species were triglycerides,monogalactosyl, digalactosyl and sulphoquinovosyl diglycerides,phosphatidyl glycerol, phosphatidyl choline (lecithin), andphosphatidyl ethanolamine; while palmitoleic, palmitic, eicosapentaenoicand eicosate-traenoic acids were the major fatty acid constituents.The two galactolipids, monogalactosyl and digalactosyl diglyceridescontained large amounts of C₁₆ and C₂₀ polyunsaturated fattyacids. Lipids of diatoms, whether grown in the light or in the dark,were the same apart from quantitative differences. More storagelipids such as triglycerides were synthesized in the light thanin the dark.     

The lipids and phospholipids of hydatid protoscolices of Echinococcus granulosus (cestoda)

Frayha G. J., Bahr G. M. and Haddad R. 1980. The lipids and phospholipids of hydatid protoscolices of Echinococcus granulosus (Cestoda). International Journal for Parasitology10: 213–216. The protoscolices of Echinococcus granulosus were isolated from hydatid cysts. The phospho- and neutral lipids of the protoscolices were determined. The seven major classes of lipids namely, phospholipids, fatty acids, mono-, di- and triglycerides, cholesterol and cholesterol esters were identified and quantitatively determined. The phospholipids isolated were cephalin, lecithin, lysolecithin, phosphatidyl inositol, phosphatidyl serine and sphingomyelin. Lecithin and cephalin were the most abundant. The signiflcance of this finding is discussed.     

Lipid composition of Mycoplasma neurolyticum

The total lipid content of Mycoplasma neurolyticum comprises about 14% of the dry weight of the organisms and is about equally distributed between the phospholipid and the neutral-glycolipid fractions. The neutral lipids were identified as triglycerides, diglycerides, and cholesterol. The glycolipid fraction contained 1-O-beta-glucopyranosyl-d-2,3-diglyceride and 1-[O-beta-d-glycopyranosyl-(1-->6)-O-beta-d-glucopyranosyl]-d-2,3-diglyceride. The latter lipid is structurally identical to the diglucosyl diglyceride which occurs in Staphylococcus aureus. The phospholipids of the organism consist of a fully acylated glycerophosphoryl-glycerophosphoryl glycerol, phosphatidic acid, diphosphatidyl glycerol, phosphatidyl glycerol, and amino acyl esters of phosphatidyl glycerol. Phosphatidic acid and phosphatidyl glycerol account for greater than 90% of the phospholipids of organisms in the exponential phase of growth. The predominant fatty acids found in all of the acyl lipids were palmitic, stearic, and oleic acids.     

Drug-induced foam cell reactions in rats, II. Chemical analysis of lipids stored in lungs and foam cells after treatment with chlorphentermine, 5-[p-(fluoren-9-ylidenemethyl)phenyl]-2-piperidineethanol (RMI 10.393) and 1-chloramitriptyline.

Lipidosis and foam cell reaction was induced in rat lungs by repeated administration of chlorphentermine, RMI 10.393 (=5-[p-(fluoren-9-ylidenemethyl)phenyl]-2-piperidineethanol), and 1-chloramitriptyline. Foam cell and lung lipids were extracted and separated in classes by thin-layer chromatography. Phospholipids were determined by phosphorus analysis, while neutral lipids were measured densitometrically. In lungs of drug-treated rats lecithin, phosphatidyl glycerol, phosphatidic acid, phosphatidyl inositol and free fatty acids accumulated in varying amounts. All other lipids were present in normal or reduced concentrations. Foam cells of chlorphentermine- and RMI 10.393-treated rats contained mainly phospholipids, i.e. lecithin and only small amounts of neutral lipids, i.e. cholesterol. Foam cells induced by 1-chloramitriptyline contained besides phospholipids also large amounts of neutral lipids, i.e. cholesterol, free fatty acids and cholesterol esters. This study and recent reports of others show that certain drugs produce a generalized metabolic disturbance characterized by accumulation of various lipids in several tissues. The distribution patterns of lipids induced by various drugs may differ considerably. This indicates that several biochemical mechanisms may be involved in the pathogenesis of drug-induced lipidosis.