scholarly journals Selective release of human adipocyte fatty acids according to molecular structure

1997 ◽  
Vol 324 (3) ◽  
pp. 911-915 ◽  
Author(s):  
Thierry RACLOT ◽  
Dominique LANGIN ◽  
Max LAFONTAN ◽  
René GROSCOLAS
Keyword(s):  
Molecular Structure ◽  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid ◽  
Chain Length ◽  
Animal Studies ◽  
Essential Fatty Acids ◽  
Monounsaturated Fatty Acids ◽  
Fat Cells ◽  
Obese Women

The objective of the present study was to investigate the mobilization of individual fatty acids from human white fat cells. Mammary adipose tissue from eight healthy non-obese women in their normal dietary state was collected, and isolated adipocytes were incubated with lipolytic agents. The mobilization of 34 individual fatty acids was measured by comparing the composition of non-esterified fatty acids (NEFA) with that of the triacylglycerols (TAG) from which they originated through lipolysis. Compared with TAG, NEFA were enriched in some polyunsaturated fatty acids with 18–20 carbon atoms. Conversely, the percentage of very-long-chain (20–22 carbon atoms) saturated and monounsaturated fatty acids was approx. 2 times lower in NEFA than in TAG. The relative mobilization (% in NEFA/% in TAG) of the most readily mobilized fatty acid (C20:5,n-3; 2.25) was more than 6-fold higher than that of the least readily mobilized (C22:1,n-11; 0.37). Relationships were found between the molecular structure of fatty acids and their mobilization rate. For a given chain length, the relative mobilization rate increased with increasing unsaturation, whereas for a given unsaturation, it decreased with increasing chain length. The relative mobilization rate for essential fatty acids decreased in the following order: C20:5,n-3 > C20:4,n-6 > C18:3,n-3 > C18:2,n-6 > C22:6,n-3. Interestingly, C20:5,n-3 and C20:4,n-6, which are respectively precursors of the 3- and 2-series of prostaglandins, were preferentially mobilized. It is concluded that fatty acids are selectively mobilized from human fat cells according to molecular structure, in full agreement with animal studies. By modulating the qualitative fatty acid supply to organs and by remodelling the fatty acid composition of adipose tissue, this selectivity would be relevant for consideration in physiology, health and epidemiology.

scholarly journals Selective mobilization of fatty acids from white fat cells: evidence for a relationship to the polarity of triacylglycerols

1997 ◽  
Vol 322 (2) ◽  
pp. 483-489 ◽  
Author(s):  
Thierry RACLOT
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid ◽  
Chain Length ◽  
Wide Spectrum ◽  
Fat Cells ◽  
Double Bonds ◽  
Fat Cell ◽  
Relative Enrichment ◽  
White Fat

Fatty acids are selectively released from white fat cells in accordance with well-defined rules relating their molecular structure and their mobilization rate, emphasizing the possible role of their physicochemical properties. Lipolysis is widely reported to work for conditions where only small amounts of substrate are available. We hypothesize that the preferential hydrolysis of a substrate fraction enriched in the most polar triacylglycerols (TAGs) reflects the pattern of selective fatty acid mobilization. Rat adipose tissue was first manipulated by dietary means to obtain a wide spectrum of fatty acids. Fat cell TAGs were separated into eight fractions according to polarity by liquid–liquid partition chromatography and their fatty acid proportions and compositions were determined by GLC. In the most polar TAG fractions, the relative enrichment of fatty acids (percentage in a TAG fraction divided by percentage in total TAGs) increased with the number of double bonds for a given chain length, whereas it decreased with increasing chain length for a given degree of unsaturation. The relative enrichment of highly mobilized fatty acids (16–20 carbon atoms and four or five double bonds) was very high (more than 2.5) in the most polar TAG fractions, whereas that of weakly mobilized fatty acids (20–24 carbon atoms and no or one double bond) was very low (less than 0.5). The relative enrichment of moderately mobilized fatty acids (comprising all the others) was close to unity. Our study shows that the relative enrichment of fatty acids in the most polar adipose tissue TAGs is consistent with their relative mobilization rates. This supports our hypothesis and raises the possibility that the molecular species of TAGs might be one of the regulating factors.

Selectivity of fatty acid mobilization: a general metabolic feature of adipose tissue

1995 ◽  
Vol 269 (5) ◽  
pp. R1060-R1067 ◽  
Author(s):  
T. Raclot ◽  
E. Mioskowski ◽  
A. C. Bach ◽  
R. Groscolas
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Chain Length ◽  
Acid Composition ◽  
Fat Cells ◽  
Adipose Tissues ◽  
Metabolic Feature ◽  
Fatty Acid Mobilization

This study extends our earlier work (T. Raclot and R. Groscolas. J. Lipid Res. 34: 1515-1526, 1993), which showed that, under norepinephrine-stimulated lipolysis, fatty acids of rat retroperitoneal fat cells are selectively mobilized. The present study examines whether this selective mobilization of fatty acids 1) is based on their proportions in adipose tissue, 2) is a metabolic feature common to all adipose tissues, and/or 3) depends on the lipolysis-stimulating agent. Rat fat cells with two markedly different fatty acid compositions were isolated from four white adipose tissues and treated with three lipolytic agents. Fatty acid composition of in vitro released free fatty acids was compared with that of fat cell triacylglycerols, the ratio of percent in free fatty acid to percent in triacylglycerol being defined as the relative mobilization rate (RMR). The RMR of individual fatty acids was related to their molecular structure. It increased exponentially with unsaturation for a given chain length and decreased with increasing chain length for a given unsaturation. The selectivity of fatty acid mobilization was similar regardless of the fatty acid composition of adipose tissue, the tissue location, and the lipolytic agent used. Under conditions of stimulated lipolysis, the selectivity of fatty acid mobilization is therefore a general metabolic feature of adipose tissue. Fatty acids with 16-20 carbon atoms and 4 or 5 double bonds had the highest RMR (from 1.4 to > 5), whereas fatty acids with 20-22 carbon atoms and 0 or 1 double bond had the lowest RMR (from 0.3 to 0.7). For the other fatty acids, RMR was close to unity.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Composition of human adipose tissue from deep and subcutaneous sites

1971 ◽  
Vol 25 (3) ◽  
pp. 377-380 ◽  
Author(s):  
C. G. D. BROOK
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Acid Composition ◽  
Elective Surgery ◽  
Saturated Fatty Acids ◽  
Human Adipose Tissue ◽  
Monounsaturated Fatty Acids ◽  
Gas Liquid Chromatography

1. Adipose tissue was obtained simultaneously from subcutaneous and deep sites in children undergoing elective surgery, and from different subcutaneous sites in adults. The lipid content and fatty acid composition were measured using gas-liquid chromatography and the number of cells counted after fixation in osmium tetroxide. The mean amount of lipid per cell was used as a measure of the size of the cells.2. Cells from deep sites in children were significantly smaller (P > 0.001) than those from subcutaneous sites in the same individual. Cells from different subcutaneous sites were of similar size.3. The fatty acid composition of the lipids was similar in tissue taken from the abdominal wall and from deep sites.4. The fatty acid composition of adipose tissue from the lower leg showed an increase in the monounsaturated fatty acids and a decrease in the saturated fatty acids compared with the fatty acid composition of tissue from other subcutaneous sites.

scholarly journals Physicochemical Properties, Fatty Acid Composition, Volatile Compounds of Blueberries, Cranberries, Raspberries, and Cuckooflower Seeds Obtained Using Sonication Method

Molecules ◽  
2021 ◽  
Vol 26 (24) ◽  
pp. 7446
Author(s):  
Dorota Bederska-Łojewska ◽  
Marek Pieszka ◽  
Aleksandra Marzec ◽  
Magdalena Rudzińska ◽  
Anna Grygier ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Physicochemical Properties ◽  
Volatile Compounds ◽  
High Performance ◽  
Essential Fatty Acids ◽  
Monounsaturated Fatty Acids ◽  
Rubus Idaeus ◽  
Extraction Temperature ◽  
Cardamine Pratensis

Every year, thousands of tons of fruit seeds are discarded as agro-industrial by-products around the world. Fruit seeds are an excellent source of oils, monounsaturated fatty acids, and n-6 and n-3 polyunsaturated essential fatty acids. This study aimed to develop a novel technology for extracting active substances from selected seeds that were obtained after pressing fruit juices. The proposed technology involved sonification with the use of ethyl alcohol at a low extraction temperature. Seeds of four species—blueberry (Vaccinium myrtillus L.), raspberry (Rubus idaeus), cranberry (Vaccinium macrocarpon), and cuckooflower (Cardamine pratensis)—were used for extraction. Following alcohol evaporation under nitrogen, the antioxidant activity, chemical composition, and volatile compounds of the obtained extracts were analyzed using chromatographic methods, including gas chromatography (GC)–mass spectrometry (MS) (GC–MS/MS), and high-performance liquid chromatography–MS. We analyzed physicochemical properties, fatty acid, and volatile compounds composition, sterol and tocochromanol content of blueberry, cranberry, raspberry, and cuckooflower seed oils obtained by sonication. This method is safe and effective, and allows for obtaining valuable oils from the seeds.

Effects of essential fatty acid deficiency on rat adrenal composition and secretory activity

1959 ◽  
Vol 197 (4) ◽  
pp. 893-896 ◽  
Author(s):  
Takuya Hayashida ◽  
Oscar W. Portman
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Essential Fatty Acid ◽  
Corn Oil ◽  
Essential Fatty Acids ◽  
Secretory Activity ◽  
Monounsaturated Fatty Acids ◽  
Essential Fatty Acid Deficient ◽  
Fatty Acid Deficiency

The effect of feeding diets deficient in essential fatty acids on the composition of adrenal lipids and on the secretory activity of adrenocortical hormones was studied. Rats which were fed diets devoid of fat had lower levels of tetraenoic and pentaenoic acids and higher levels of trienoic acids in both the total lipid and cholesterol ester fraction than did rats receiving a supplement of corn oil. There was a greater accumulation of cholesterol esterified with saturated and monounsaturated fatty acids in the adrenals of the rats fed essential fatty acid-deficient diets. The adrenals of the essential fatty acid-deficient rats secreted smaller quantities of steroid hormones in vitro under the stimulation of ACTH.

scholarly journals Site differences in the fatty acid composition of subcutaneous adipose tissue of obese women

1979 ◽  
Vol 42 (1) ◽  
pp. 57-61 ◽  
Author(s):  
Ph. G. Pittet ◽  
D. Halliday ◽  
P. E. Bateman
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Acid Composition ◽  
Unsaturated Fatty Acids ◽  
Saturated Fatty Acids ◽  
Normal Weight ◽  
Gas Liquid Chromatography ◽  
Obese Women

1. Adipose tissue samples were obtained by needle biopsy from three subcutaneous sites (thigh, abdomen and upper arm) in twenty-two obese women. The fatty acid composition was determined using gas-liquid chromatography and the results presented relate to eleven component fatty acids.2. The fatty acid composition of adipose tissue obtained from the arm and abdomen was remarkably similar, with the exception of the levels of lauric acid.3. The analyses showed that the majority of the saturated fatty acids were present in smaller proportions whilist the majority of unsaturated fatty acids were present in larger proportions in the thigh than in the two other sites. Highly significant inter-site differences were demonstrated for six of the major fatty acids and also for both the total amounts of saturated and unsaturated fatty acids and their ratios.4. No marked differences in the fatty acid composition of adipose tissue from obese subjects were revealed during this study when compared with previously reported results obtained from ‘normal-weight’ subjects.

scholarly journals INFLUENCE OF DIETARY FAT LEVEL ON GROWTH AND BODY COMPOSITION OF THE NEONATAL PIG

1985 ◽  
Vol 65 (1) ◽  
pp. 175-184 ◽  
Author(s):  
N. K. SARKAR ◽  
J. K. G. KRAMER ◽  
J. I. ELLIOT ◽  
M. S. WOLYNETZ
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid ◽  
Dietary Fat ◽  
Fatty Acid Biosynthesis ◽  
De Novo ◽  
Essential Fatty Acids ◽  
Fat Content ◽  
Acid Biosynthesis

Four Yorkshire piglets, from each of 18 litters, were randomly allotted within litters, to four treatment groups 12 h after birth. Group 1 (Control) continued to be suckled by sows; the remaining piglets were reared artificially on a semi-synthetic liquid diet containing either 25% soybean oil (SBO) (group 2) or 3% SBO plus 22% lactose (groups 3 and 4). At 7, 14 and 21 days of age, 24 pigs from six litters were killed. Piglets on the 25% SBO diet grew faster (P < 0.05) than those on the 3% SBO diet while the growth rate of the suckled piglets tended to be between the growth rates of those on the two SBO diets. Body fat content increased with the fat content in the diet and with age. The protein:fat ratio was greatest in the piglets on the 3% SBO diet and least in the suckled piglets. The fatty acid composition of backfat changed, primarily during the first week of life, towards that of the dietary fat. This was evident even in piglets on the low fat-high carbohydrate (3% SBO) diet. The composition of the fat deposited in piglets on the 3% SBO group indicated preferential utilization of essential fatty acids and little de novo synthesis of fatty acids. The amount and type of fat deposited by piglets fed the 3% SBO diet, together with preliminary evidence of low incorporation of radioactivity from (U14C) glucose with adipose tissue fatty acids in vivo, suggest that the de novo fatty acid biosynthesis in adipose tissue of piglets is not as high as previously reported (Mersmann et al. 1973). Key words: Neonatal pigs, fat deposition, fatty acid biosynthesis.

Fatty acid esterifying enzymes in rat adipose tissue homogenates

1968 ◽  
Vol 46 (9) ◽  
pp. 1039-1045 ◽  
Author(s):  
Anna M. Daniel ◽  
David Rubinstein
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid ◽  
Acid Phosphatase ◽  
Chain Length ◽  
Significant Alteration ◽  
Ph Optimum ◽  
Tissue Homogenates ◽  
Rat Adipose Tissue

Some characteristics of enzymes in homogenates of rat adipose tissue concerned with esterification of fatty acids have been investigated. Acyl-CoA thiokinase is the most active of the enzymes studied, with optimal concentrations of palmitate and ATP being 2 mM and 25 mM respectively. The thiokinase has a pH optimum between 8 and 10 and reacts with fatty acids ranging in chain length from C4 to C22, with the greatest activity towards palmitate. About 50% of the activity is found in the 100 000 × g supernatant. Acyl-CoA : α-glycerolphosphate acyltransferase and acyl-CoA deacylase have pH optima between 7 and 8. Albumin at a concentration of 1% activates the former, while the latter is inhibited by concentrations of albumin greater than 0.5%. Deacylase activity is found almost entirely in the 100 000 × g supernatant. Both the acyl-CoA : α-glycerolphosphate acyltransferase and the acyl-CoA : diglyceride acyltransferase lose much of their activity upon fractionation. The pH optimum of the acyl-CoA : diglyceride acyltransferase ranges from pH 7 to 9, while that of the phosphatidc acid phosphatase is 6. The latter enzyme is distributed equally between particulate and soluble portions of the homogenate. When these enzymes are assayed in homogenates from fed and fasted animals, a significant alteration is found only in the level of acyl-CoA deacylase, which is decreased. The properties of these enzymes can be related to the extent and type of esterification in homogenates from fed and fasted animals.

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