Acid Composition Of Adipose Tissue Research Articles

Interrelation of Fatty Acid Composition in Adipose Tissue, Serum, and Liver of Dairy Cows During the Development of Fatty Liver Postpartum

We investigated the composition of fatty acids in adipose tissue, serum, and liver of cows that were fed at restricted energy intake or were overfed during the dry period. Overfed cows had higher concentrations of serum nonesterified fatty acids and consequently accumulated greater amounts of triacylglycerols in the liver than did cows that were fed at restricted energy intake. The percentages of the different fatty acids present in adipose tissue were similar for both groups and did not change during sampling intervals. Before parturition, concentrations of the individual fatty acids present in serum were similar between groups. After parturition, concentrations of major fatty acids in serum, including palmitic, stearic, oleic, and linoleic acids significantly increased in both groups and were higher in overfed cows than in cows that were fed at restricted energy intake. The shift of concentrations of the different fatty acids present in the liver—as a result of increased lipolysis—was observed in palmitic, oleic, and linoleic acids but not stearic acid, suggesting that stearic acid is used by the liver (i.e., oxidation) or is considerably secreted through the milk, thereby not increasing in accumulation in the liver. In conclusion, different feeding regimens during the dry period do not influence the composition of fatty acids in adipose tissue. More intensive lipolysis results in increased concentrations of palmitic, stearic, oleic, and linoleic acids in the blood; subsequently, these fatty acids, excluding stearic acid, greatly accumulated in the liver.

The influence of goat genotype on the production of Capretto and Chevon carcasses. 4. Chemical composition of muscle and fatty acid profiles of adipose tissue

The chemical composition of muscle and the fatty acid composition of adipose tissue from the carcasses obtained from 50 buck kids from five genotypes (10 kids/genotype), Boer x Angora (BA), Boer x Saanen (BS), Feral x Feral (FF), Saanen x Angora (SA) and Saanen x Feral (SF) reared for Capretto and Chevon production, were compared. Genotype did not influence the chemical composition of muscle except for muscle from BA carcasses, which had significantly higher extractable fat content. The proportions of individual fatty acids differed significantly between genotypes for the Capretto kids. Adipose tissue from the Capretto group had a higher concentration of palmitic acid (31–34%), while the proportion of oleic acid (37–40%) was greater in the Chevon group. With an increase in age and resultant change in diet, the saturated fatty acid concentration decreased and the unsaturated fatty acid concentration increased.

Relation between the intake of milk fat and the occurrence of conjugated linoleic acid in human adipose tissue

Conjugated linoleic acid (CLA) is a group of naturally occurring fatty acids mainly present in fats from ruminants. CLA has been shown to be a potential anticarcinogen. In this study, the relation between bovine milk fat intake and the occurrence of CLA in human adipose tissue was investigated. One hundred twenty-three men weighed and recorded the foods they consumed for 1 wk. Afterward, recall interviews were conducted by telephone monthly for 7 consecutive months to inquire about food consumption during the previous 24 h. The entire dietary recording procedure was repeated once. The fatty acid composition of adipose tissue and serum was analyzed. The average amount of one isomer of CLA--9-cis,11-trans-octadecadienoic acid (9c,11t-18:2)--as a percentage of total fatty acids was found to be 0.50% in adipose tissue and 0.25% in serum. The amount of 9c,11t-18:2 in adipose tissue was significantly correlated with milk fat intake (r = 0.42). The percentage of 9c,11t-18:2 in both adipose tissue and in serum was strongly correlated with myristoleic acid (14:1). The amount of 9c,11t-18:2 in human adipose tissue was significantly related to milk fat intake.

Fatty acid composition and cholesterol concentration in tissues of white-tailed deer ( Odocoileus virginianus) as influenced by lactation, age, and season of the year

The purpose of this study was to determine effects of lactation, season, and age on fatty acid compositions of adipose tissue (subcutaneous and perirenal), liver, and muscle (m. longissimus dorsi), and on cholesterol concentration of liver and muscle, of female white-tailed deer ( Odocoileus virginianus). Lactation did not affect fatty acid composition in adipose tissue or muscle, but in liver, weight percentages of 18:2 were lower, and of 20:4 higher in non-lactating does. Increased age (fawns, yearlings, 2 and 3+-years old) decreased 14:0, 15:0, and 16:0 in subcutaneous adipose tissue; decreased 14:0, 15:0, 16:1, 18:2, and increased 18:0 in perirenal adipose tissue; increased 18:1 and decreased 18:2 in liver; and increased 18:1, 18:3, and 20:4, and decreased 18:2 in muscle. Season of the year had little effect on adipose tissue and muscle fatty acids. Liver of fall season does had greater concentrations of most fatty acids than winter does, and cholesterol concentration was greatest in liver of winter does. It was concluded that season and lactation minimally affect fatty acid composition in adipose and muscle, whereas changes in saturated and unsaturated fatty acids occur with increased age. Also, liver fatty acids are influenced by each parameter studied, but cholesterol varies only with season.

The intake of polyunsaturated fatty acids by cats is reflected in their adipose tissue

Summary To find out whether the composition of the subcutaneous adipose tissue of cats reflects the intake of polyunsaturated fatty acids, we performed a feeding trial. Six groups of kittens were fed on diets with variable combinations of corn, linseed, and fish oil. After 5 months, biopsies of subcutaneous adipose tissue were analysed for their contents of linoleic, α‐linolenic, eicosapentaenoic, and docosahexaenoic acid. The observed strong correlations between dietary and fat tissue polyunsaturated fatty acids indicate that the fatty acid composition of adipose tissue may be used as an index of the fatty acid composition of the diet. Thus, in epidemiological studies on the possible relationship between dietary fat type and feline disease the fatty acid composition of adipose tissue might be a useful measure.

Stearoyl-CoA Desaturase Activity in Adipose Tissues and Liver of Growing Large White and Meishan Pigs

Stearoyl-CoA desaturase activity was measured in adipose tissue (backfat and neckfat) and liver microsomes of Large White and Meishan pigs. Preliminary assays have shown that Δ9-desaturase activity cannot be measured on frozen tissues, because freezing involves a loss in activity of 40–50%. The specific activity of liver Δ9-desaturase was much lower than that of the adipose tissues in both breeds, indicating that the liver is not a major site of oleate synthesis in the pig. The hepatic Δ9-desaturase activity was higher in Meishan than in Large White pigs. However, Δ9-desaturase activity in the adipose tissue of Large White pigs was much higher than that of Meishan pigs, even though the percentage of oleate was slightly higher in the adipose tissues of the latter. This investigation has demonstrated that differences in fatty acid composition of adipose tissues between Large White and Meishan pigs cannot be attributed to differences in Δ9-desaturase activity at this stage of maturity. These results suggest that the higher oleate percentage in Meishan adipose tissues would result from a higher Δ9-desaturase activity at an earlier age.

Selective release of human adipocyte fatty acids according to molecular structure.

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.

Noninvasive characterization of neonatal adipose tissue by 13C magnetic resonance spectroscopy

In vivo 13C magnetic resonance spectroscopy (MRS) was applied noninvasively to analyze the fatty acid composition of adipose tissue in 21 full-term newborn infants and 6 mothers. In order to assess the effects of gestational and postnatal age on adipose tissue composition, we studied preterm infants at birth, term infants at the ages of 6 wk and at 6 mon. We also investigated the influence of maternal diet on infant adipose tissue composition by studying the breast-fed infants of women who maintained either an omnivore or a vegan diet. Significant differences were observed in adipose tissue composition of neonates compared with their mothers. Neonates had more saturated and less unsaturated fatty acids than their mothers (P < 0.01). We also observed changes in adipose tissue composition with maturity. From birth to 6 wk of age 13C MR spectra showed a significant increase in the amount of unsaturated fatty acids, particularly polyunsaturated fatty acids (P < 0.01). Similarly, differences were seen as a result of gestational age. Preterm infants had relatively fewer unsaturated fatty acids than full-term infants. A greater proportion of these unsaturated fatty acids were polyunsaturated. Our results demonstrate that 13C MRS can be utilized to assess noninvasively neonatal adipose tissue lipid composition and to monitor the effects of developmental changes due to gestational age and oral feeding.

Fatty acid composition of adipose tissue, an indication of dietary fatty acids, and breast cancer prognosis.

Fatty acid composition of adipose tissue is an indicator of the long-term ingestion pattern of several specific fatty acids. There is good correlation of antecedent diet with the essential fatty acids, and there is reflection of the diet with the fatty acids that can be synthesized. The relationship between the fatty acid levels and lymph node status and clinical outcome was examined. At the time of diagnostic surgery, 161 women with clinical stage T1NO breast cancer had subcutaneous adipose tissue (breast and abdominal) aspirated. The concentrations of 35 fatty acids, seven summed classes, and six fatty acid groups were measured by capillary gas chromatography. Lymph node status was determined with axillary dissection, and patients were followed-up (mean, 7.3 years) for clinical outcome. There was no significant association of any adipose tissue fatty acids with overall survival, although few (16 of 161 women) died of breast cancer. However, the odds of having positive lymph nodes (57 of 161 women) were significantly higher for women with a greater adipose tissue proportion of oleic acid (odds ratio [OR], 7.56; 95% confidence interval [CI], 1.78 to 32.1) or total saturated acids (OR, 8.43; 95% CI, 1.48 to 40.0) and significantly lower with a higher proportion of trans fatty acids (OR, 0.24; 95% CI, 0.07 to 0.77), as assessed by multivariate logistic regression. These data support previous research with dietary questionnaire methodology, suggesting that specific dietary fatty acids may be associated with breast cancer promotion. Further research with long-term clinical follow-up is necessary to investigate these observations in large, diverse populations before dietary recommendations can be envisioned.

Site-specific fatty acid composition in adipose tissues of several northern aquatic and terrestrial mammals

Site-specific differences in fatty acid compositions (by gas-liquid chromatography) were compared in aquatic, semiaquatic and terrestrial mammals: the ringed seals ( Phoca hispida hispida and P. h. botnica), otter ( Lutra lutra), raccoon dog ( Nyctereutes procyonoides), brown bear ( Ursus arctos) and grey wolf ( Canis lupus). In addition, we briefly discuss our earlier results for the Canadian beaver ( Castor canadensis) and muskrat ( Ondatra zibethicus). In both aquatic and terrestrial species, large amounts of Δ9-monounsaturated fatty acids (MUFAs) and small amounts of saturated fatty acids and exogenous long-chain MUFAs were found in the cold tissues of the extremities. In seals, the poikilothermic outer blubber had these characteristics and differed from the inner blubber. On the other hand, the subcutaneous and inner fat depots of the coated semiaquatic and terrestrial mammals were uniform. In the bare extremities, however, these mammals also had an excess of A9-MUFAs. The degree of Δ9-desaturation in the outer blubber of the seals was significantly correlated with age. The excess of Δ9-MUFAs in the bare extremities of land mammals increased the overall double bond content of these tissues compared with the inner depots. In contrast, due to the large amounts of dietary polyunsaturated fatty acids, this was not found in the aquatic and semiaquatic species. The observed site-specific differences are discussed as possible inherited evolutionary adaptations to low temperature of the tissues.

Changes in fatty acid composition in rat adipose tissue induced by dietary obesity.

The aim of the study was to evaluate the effects of cafeteria feeding on the composition of fatty acids in retroperitoneal fat pad and also to determine what happens to fatty acids when rats previously fed the cafeteria diet are returned to regular rat chow. The study of the post-cafeteria rats enabled us to determine the effects of dietary induced excess weight in the absence of artefactual interferences from the diet because these rats, unlike the cafeteria obese rats, ate the same diet as controls. In response to cafeteria feeding there were increases in the majority of adipose tissue fatty acids. However, significant decreases were observed in the relative proportions of 18:2n-6 and in two related n-6 polyunsaturated fatty acids (18:3n-6 and 20:3n-6), as well as in 16:1. In the post-cafeteria obesity model the previous dietary influence on fatty acid composition was still evident. The maintenance of both the high levels and proportions of 18:1 and the decrease of 16:1 percentage in the post-cafeteria rats argues in favour of an alteration in the activity of the elongation metabolic pathway. Certain changes affecting polyunsaturated fatty acid adipose depot composition of obese rats, mainly the decreased levels of 18:2n-6, are long lasting and could be related to the maintenance of the obese status. On the whole, although the fatty acid composition of adipose tissue is influenced by the composition of the diet, there are some differences in both the maintenance of the effects and also in the selectivity of adipose tissue for the different fatty acids of obese and lean rats.

Fatty acids in extremity tissues of finnish beavers ( Castor canadensis and Castor fiber) and muskrats ( Ondatra zibethicus)

Site-specific differences in fatty acid composition of adipose tissues from Finnish beavers (Castor canadensis and Castor fiber) and muskrats (Ondatra zibethicus) were studied by gas liquid chromatography. In the total lipids of heterothermic extremities the proportions of potentially endogenous (Δ9-desaturated) monoenoic fatty acids were 1.5-fold and those of the saturated fatty acids 0.5-fold the proportions of subcutaneous or inner depots. Thus the role of Δ9-desaturation in the biochemical adaptation of the extremity tissues is discussed. Dietary polyunsaturated fatty acids, with the exception of 18:3ω3 in the beavers, did not accumulate selectively in the extremity tissues. The liver of the muskrat (which also eats fish and mussels) contained high proportions of 22:6ω3, which was a minor component in the beaver (exclusively a herbivore).

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

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)

Plasma factor VII levels: Relationships to fatty acid composition of adipose tissue in healthy men

Plasma factor VII levels: Relationships to fatty acid composition of adipose tissue in healthy men

Adipose tissue isomeric trans fatty acids and risk of myocardial infarction in nine countries: the EURAMIC study

Dietary isomeric trans fatty acids—mainly produced by hydrogenation of oils—are suspected of increasing the risk of coronary heart disease. Dietary trans fatty acid intake is reflected in the fatty acid composition of adipose tissue. In an international multicentre study in eight European countries and Israel (EURAMIC), adipose tissue aspiration samples were obtained from 671 men with acute myocardial infarction (AMI), aged 70 years or less, and 717 men without a history of AMI (controls). The proportion of fatty acids, including isomeric trans monoenoic fatty acids with 18 carbon atoms (C18:1), was determined by gas chromatography. Although there were considerable differences between countries in mean (SD) proportion of adipose tissue C18:1 trans fatty acids, there was no overall difference between cases (1·61 [0·92]%) and the controls (1·57 [0·86]%). The risk of AMI did not differ significantly from 1·0 over quartiles of adipose C18:1 trans fatty acids: the multivariate odds ratio was 0·97 (95% Cl 0·56-1·67) for the highest versus lowest quartile. After exclusion of subjects from Spanish centres because they had far lower proportions of adipose trans fatty acids than subjects from other countries, there was a tendency to increased risk of AMI in the upper quartiles of C18:1 trans; however, the trend was not statistically significant. Our results reflect considerable differences between countries in dietary intake of trans fatty acids but do not suggest a major overall effect of C18:1 trans fatty acids on risk of AMI. We cannot exclude the possibility that trans fatty acids have a significant impact on risk of AMI in populations with high intake.

Developing Yoshida sarcoma does not influence the fatty acid composition of adipose tissues in the rat.

The potential involvement of individual fatty acids from diet or from adipose tissue in the outcome of cancer emphasizes the need for more insight into the relationship between fatty acids and tumor growth. The main objective of the present study was to examine whether rapid tumor growth would induce changes in the fatty acid composition of adipose tissue, indicating selective use and thus deposition of dietary fatty acids and/or selective removal of stored fatty acids from adipose tissue. We used a rodent model of transplanted solid tumor (Yoshida sarcoma) and measured the fatty acid composition from different adipose sites in the absence and in the presence of tumor but at the same intake of dietary fatty acids. We found that Yoshida sarcoma could grow rapidly without significantly altering the fatty acid composition of adipose tissue, irrespective of its location. These results do not favor the hypothesis of a selective removal of fatty acids from adipose tissue by growing tumors. They moreover indicate that tumors do not modify the storage of individual dietary fatty acids.

Effect of Growth Hormone Administration on the Fatty Acid Composition of Adipose Tissue in Growth-Hormone-Deficient Men

In adult patients with growth hormone deficiency, the fatty acid composition of abdominal and gluteal fat tissues was determined prior to and at several time points after administration of recombinant human growth hormone. Values obtained before growth hormone treatment were not different from those seen in a normal population. However, as in healthy individuals, significant differences were found in the composition of the fat sampled at the different sites. Administration of growth hormone had no effect on the composition. It is concluded that a change in fatty acid composition of fat tissue is unlikely to be a factor contributing to the reported increased cardiovascular mortality in hypopituitarism and that treatment with recombinant human growth hormone has no effect on that potential cardiovascular risk factor.

Essential fatty acid consumption and risk of breast cancer.

Animal and ecological studies of essential fatty acids suggest that omega-3 fatty acids found in fish oils and omega-6 fatty acids found in vegetable oils may be playing a role in the etiology of breast cancer. Essential fatty acids may modulate breast cancer risk by interacting with prostaglandins, which have immunosuppressive and platelet aggregative capabilities. The fatty acid composition of adipose tissue reflects the dietary consumption of essential fatty acids over a period of years. Biochemical techniques have been used in epidemiological studies to accurately estimate fatty acid consumption. However, analytical epidemiology studies that have used biochemical measurements of adipose tissue fatty acid composition, have not supported a relationship between consumption of these essential fatty acids and breast cancer risk.

Effect of dietary canola on fatty acid composition of bovine adipose tissue, muscle, kidney, and liver.

The purpose of this study was to determine effects of feeding canola and soybean products as protein supplements on fatty acid composition of adipose tissue and muscle of slaughter bulls and steers and on fatty acid composition of kidney and liver total lipids of bulls. Products included canola meal (CM), extruded canola (EC, full-fat), ground canola (GC, full-fat), soybean meal (SBM), and extruded soybeans (ES, full-fat). Tissues were obtained at slaughter from 75 crossbred beef bulls and 50 crossbred beef steers fed corn silage (17.2 to 29.7% of DM), ground corn (56.5 to 75.0% of DM), and protein supplements (6.8 to 21.6% of DM). The DMI was not influenced by dietary fat in either trial. Gain: feed was greater (P < .05) for bulls fed CM than for bulls fed ES, EC, or GC. Carcasses were not influenced appreciably by dietary fat. Adipose tissue of EC-fed cattle had the lowest percentage of 16:0 (P < .05, vs SBM, CM, and GC), whereas both EC- and GC-fed cattle had the highest 18:0 (P < .05). In muscle (pectoral), EC-fed bulls had a higher percentage of 18:1 than SBM-fed bulls (P < .05), and EC-fed steers had the lowest 16:0 and 16:1 and highest 18:0, 18:3, and 20:1 (P < .05). Kidney total lipids of EC- and GC-fed bulls had the lowest percentage of 16:0 and highest 18:1 and 18:3 (P < .05); bulls fed ES had the highest percentage of 18:2. Liver-lipid 16:0 was highest in ES-fed bulls and lowest in EC-fed bulls, which also had the highest 18:0 (P < .05). Bulls fed EC and GC had the highest 18:3 and 20:5 (P < .05). In conclusion, dietary full-fat canola and in some cases full-fat soybeans altered the fatty acid composition of lipids of adipose tissue, muscle, kidney, and liver of beef cattle.

Fatty acid composition of adipose tissues in familial lipoprotein lipase deficiency

Fatty acid composition of adipose tissues in familial lipoprotein lipase deficiency