scholarly journals Albumin stimulates the release of lysophosphatidylcholine from cultured rat hepatocytes

1988 ◽  
Vol 253 (3) ◽  
pp. 693-701 ◽  
Author(s):  
D J Baisted ◽  
B S Robinson ◽  
D E Vance

The effect of albumin on the release of [3H]lysophosphatidylcholine from cultured rat hepatocytes prelabelled with [Me-3H]choline was studied. In the absence of serum and albumin from the medium, the cells released essentially no [3H]lysophosphatidylcholine. Albumin stimulated this process dramatically, and it reached a plateau at 2 mg/ml. After an initial lag of 30 min, the release of [3H]lysophosphatidylcholine was linear for at least 4 h. At low concentrations, albumin slightly stimulated [3H]phosphatidylcholine release. The albumin had no measurable effect on the metabolism of cellular [3H]phosphatidylcholine, [3H]lysophosphatidylcholine or [3H]glycerophosphocholine. In addition, albumin did not alter the release of 3H-labelled water-soluble compounds, including [3H]glycerophosphocholine, into the medium. The possibility that the [3H]lysophosphatidylcholine was arising from catabolism of [3H]phosphatidylcholine in the medium by secreted enzymes was excluded. The effect on [3H]lysophosphatidylcholine secretion was also observed when the cells were incubated with alpha-cyclodextrin, a cyclic polysaccharide that has the ability to bind lysophosphatidylcholine. The albumin-released lysophosphatidylcholine was enriched in unsaturated fatty acids. Alteration of the fatty acid composition of cellular phosphatidylcholine gave rise to parallel changes in phosphatidylcholine and lysophosphatidylcholine in the medium. It is concluded that phosphatidylcholine is constantly being degraded in the rat hepatocyte to lysophosphatidylcholine which is released into the medium only when a suitable acceptor is present.

1989 ◽  
Vol 264 (1) ◽  
pp. 125-131 ◽  
Author(s):  
B S Robinson ◽  
D J Baisted ◽  
D E Vance

We have investigated the albumin-stimulated release from cultured rat hepatocytes of lysophosphatidylcholine derived from methylation of phosphatidylethanolamine and of lysophosphatidylethanolamine. In the absence [corrected] of albumin, neither lysophosphatidylethanolamine nor lysophosphatidylcholine was released into the culture medium. Albumin stimulated the accumulation of both phospholipids in the medium. After 2 h, 14.1 nmol of lysophosphatidylcholine and 2.0 nmol of lysophosphatidylethanolamine per 3 x 10(6) cells had accumulated in the medium. The rate of release of [3H]ethanolamine-labelled lysophosphatidylethanolamine was rapid in the first 2 h and then was decreased, whereas there was a 1 h lag in the release of [3H]ethanolamine-labelled lysophosphatidylcholine. This apparent lag probably reflected the time necessary for the synthesis of phosphatidylcholine from phosphatidylethanolamine in the cells. Albumin caused a decrease in labelled cellular lysophosphatidylethanolamine and lysophosphatidylcholine which only partially accounted for the accumulation of the labelled phospholipids in the medium. Albumin also stimulated the release of labelled phosphatidylethanolamine (almost 3-fold) and phosphatidylcholine (2-fold) into the medium. There was no detectable change in the labelling of the cellular pools of these phospholipids, most likely owing to the large amounts in the cells compared with the medium. The labelled lysophospholipids did not arise from catabolism of the parent phospholipid in the medium. Analysis of the fatty acids of the secreted lysophospholipids showed a preferential release of unsaturated fatty acyl species of lysophosphatidylcholine, whereas lysophosphatidylethanolamine contained similar amounts of saturated and unsaturated fatty acids.


2004 ◽  
Vol 71 (1) ◽  
pp. 46-50 ◽  
Author(s):  
Dorthe Kristensen ◽  
Rikke V Hedegaard ◽  
Jacob H Nielsen ◽  
Leif H Skibsted

Milk from cows fed a low-fat diet high in cereals designed to stimulate fat synthesis de novo was lower in unsaturated fatty acids (21·3%) than milk from cows fed a diet high in fat, mainly from roasted soy beans (41·3% unsaturated fatty acids). Buttermilk from the more unsaturated milk was less oxidatively stable during storage (at 4 °C, followed for 11 d) than buttermilk from the more saturated milk, as monitored both by primary lipid oxidation products (lipid hydroperoxides) and by the secondary lipid oxidation product, hexanal. Fat-soluble antioxidants, β-carotene and α-tocopherol, analysed by HPLC, were not consumed during storage for either of the two types of buttermilk. In contrast, the antioxidative capacity of the serum phase decreased during storage as evaluated in a radical scavenging assay based on the semi-stable water-soluble radical nitrosodisulphonate (Fremy's salt). The time course for the decrease in water-soluble antioxidants was very similar for the two types of buttermilk suggesting that oxidation is initiated in the serum phase independently of fatty acid composition.


1991 ◽  
Vol 276 (1) ◽  
pp. 209-215 ◽  
Author(s):  
A Gomez-Muñoz ◽  
P Hales ◽  
D N Brindley

Oleate, linoleate, linolenate, arachidonate and eicosapentaenoate, but not myristate, palmitate and stearate, stimulated glycogen phosphorylase activity by 2-8-fold when added to cultured rat hepatocytes. Addition of BSA or Ca2- to the incubation medium decreased the stimulating effects of the unsaturated fatty acids. The combination of oleate or linolenate, with corticosterone, testosterone or estradiol produced synergistic stimulations of phosphorylase activity. The stimulation of glycogen phosphorylase activity by linolenate was inhibited by staurosporine or sphingosine. Staurosporine (80 nM) alone also decreased basal phosphorylase activities by about 60%. The results show that unsaturated fatty acids can be used as model agonists to stimulate phosphorylase activity by a mechanism that probably involves protein kinase C. On the basis of the fatty acid: BSA ratios used, this stimulation should only occur in vivo at high fatty acid concentrations when accompanied by hypoalbuminaemia.


2020 ◽  
Vol 82 (6) ◽  
pp. 71-78
Author(s):  
Zita Letviany Sarungallo ◽  
Budi Santoso ◽  
Risma Uli Situngkir ◽  
Mathelda Kurniaty Roreng ◽  
Meike Meilan Lisangan

Refining of crude red fruit oil (CRFO) through the degumming and neutralization steps intended to produce oil free of impurities (non triglycerides) such as phospholipids, proteins, residues and carbohydrates, and also reducing the amount of free fatty acids (FFA). This study aims to determine the effect of red fruit oil purification through degumming and neutralization stages on chemical properties, fatty acid composition, carotenoid content and tocopherol of red fruit oil (RFO). The results showed that degumming of CRFO did not affect the decrease in water content, FFA levels, peroxide numbers, iodine values, carotenoids and tocopherols content; but decrease in levels of phosphorus, β-carotene and α-tocopherol. Neutralization of degummed-RFO (DRFO) did not affect the decrease in water content, iodine value, carotenoid, tocopherol and α-tocopherol; but the FFA levels, peroxide number, phosphorus and β-carotene levels decreased significantly. The fatty acid composition of RFO was dominated by unsaturated fatty acids (± 75%), which increases through degumming and neutralization stages. β-carotene is more sensitive than α-tocopherol during refining process of crude oil, but in general, this process can improve the RFO quality.


Author(s):  
Syamsul RAHMAN ◽  
Salengke Salengke ◽  
Abu Bakar TAWALI ◽  
Meta MAHENDRADATTA

Palado (Aglaia sp) is a plant that grows wild in the forest around Mamuju regency of West Sulawesi, Indonesia. This plant is locally known as palado. Palado seeds (Aglaia sp) can be used as a source of vegetable oil because it contains approximately 14.75 % oil, and it has the potential to be used as food ingredients or as raw material for oil production. The purpose of this study was to determine the chemical properties and the composition of fatty acids contained in palado seed oil (Aglaia sp). The employed method involved the use of palado fruit that had been processed to be palado seed and undergoing flouring process. Palado flour was produced by the extraction process by using chloroform solvent with the soxhlet method. The characteristics of the chemical properties in the oil produced were analyzed by using a standard method, including iodine, saponification, and acid values. The analysis of fatty acid composition was conducted by using gas chromatography. The results showed that palado oil extracted with hexane had an iodine value of 15.38 mg/g, saponification value of 190.01 mg KOH/g, and acids value of 1.961 mg KOH/g. The fatty acid composition of the palado seed oil consisted of saturated fatty acids (41.601 %), which included palmitic acid (41.062 %), myristic acid (0.539 %), and unsaturated fatty acids (45.949 %), which included mono-unsaturated fatty acids (MUFA) such as (22.929 %), oleic acid and poly-unsaturated fatty acids (PUFA), which was linoleic acid (23.020 %).


Author(s):  
L. P. Nilova ◽  
S. M. Malyutenkova

The results of studies of the biochemical composition and antioxidant properties of nuts sold in the consumer market of St. Petersburg were presented in the work. The objects of research were kernels of nuts: sweet almonds, hazelnuts, cashews, walnuts. Total Soxhlet lipids, fatty acid composition, vitamin E, fractional composition of tocopherols and phytosterols, total phenolic compounds and flavonoids, antioxidant activity by FRAP with ferric chloride, o-phenanthroline and Triton X 100 were determined in nuts. Nuts varied in lipid content (42.6–65.4%) with a predominance of unsaturated fatty acids from 80.4 to 92.4 relative%. Oleic acid prevailed in the fatty acids of almonds, hazelnuts and cashews, while linoleic acid prevailed in walnuts. Walnuts contained the highest amount of polyunsaturated fatty acids. The antioxidant properties of nuts were formed by a complex of water and fat-soluble antioxidants. Fat-soluble antioxidants included vitamin E with a predominance of ?-tocopherol in the kernels of sweet almonds and hazelnuts, ?-tocopherol - in walnuts and cashews. Only sweet almond kernels contained all the tocopherol fractions. ?- and ?-tocopherols were absent in hazelnut lipids, while ?-tocopherols were absent in cashews and walnuts. ?-sitosterol, campesterol and stigmasterol with a predominance of ?-sitosterol were identified in the composition of phytosterols in all nut kernels. Water-soluble antioxidants are mainly represented by phenolic compounds, the amount of which varies widely depending on the type of nuts: cashews


Pharmacia ◽  
2019 ◽  
Vol 66 (4) ◽  
pp. 201-207 ◽  
Author(s):  
Olena O. Iosypenko ◽  
Viktoriia S. Kyslychenko ◽  
Zinaida I. Omelchenko ◽  
Iryna S. Burlaka

The qualitative composition and quantitative content of fatty acids in leaves of vegetable marrows (Cucurbita pepo L. var. giromontina Alef.), zucchini (Cucurbita pepo L. var. cylindrica Paris) yellow- and green-fruits varieties were determined by using GC/MS. 14 fatty acids were identified as the result of the experiment. Unsaturated fatty acids were found to be dominated in the raw plant material. The total content of unsaturated fatty acids amounted to 60.47% in vegetable marrows leaves, 64.35% yellow zucchini leaves and 68.85% green zucchini leaves, among which linoleic and linolenic acid dominated. The related health lipid indices (IA, atherogenicity, IT, thrombogenicity and IH, health) were determined. It is shown that the use of such biological resources is actual and expedient for the purpose of alimentary correction of the physiological condition of a person.


1972 ◽  
Vol 71 (1) ◽  
pp. 62-72 ◽  
Author(s):  
Knut Kirkeby

ABSTRACT The fatty acid composition of cholesterol esters, phospholipids, and triglycerides of the serum has been studied in groups of hyperthyroid and hypothyroid women and also in control material matched for age. In hyperthyroidism, a decrease in the proportions of linoleic acid and an increase in the proportions of some saturated and mono-unsaturated fatty acids were observed. When absolute concentrations were considered, it appeared that the decrease in linoleic acid was almost equivalent to the entire decrease in total fatty acids in the serum of the hyperthyroid patients. In hypothyroidism no changes were noted in the proportions of linoleic, saturated and mono-unsaturated fatty acids, and the absolute concentrations reflected the general increase in serum lipids. It is believed that these findings may be explained by the changes in lipid turnover which are known to occur in disturbances of thyroid function. In hyperthyroidism, they lead to a linoleic acid deficiency, while a sparing effect must be operating in hypothyroidism. The finding of relatively high linoleic acid values combined with hyperlipaemia in hypothyroidism seems to be characteristic of the condition, since other types of hyperlipaemia are almost invariably combined with low percentages of linoleic acid. Results regarding arachidonic and eicosatrienoic acid are consistent with increased synthesis in hyperthyroidism, and decreased synthesis in hypothyroidism.


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