Conjugated linoleic acids (CLA) as precursors of a distinct family of PUFA

Banni, Sebastiano; Petroni, A.; Blasevich, M.; Carta, Gianfranca; Cordeddu, Lina; Murru, Elisabetta; Melis, Maria Paola; Mahon, Anne; Belury, Martha A.

doi:10.1007/s11745-004-1341-0

Cited by 52 publications

(29 citation statements)

References 28 publications

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“…1, 2 ). As we could defrom other groups showing that this CLA isomer in particular is well metabolized up to CFA 20:3 and 20:4 ( 14,29,30 ). In contrast, the t9, t11-CLA isomer is only elongated to CFA 20:2 and CFA 22:2, but it is not desaturated.…”

Section: Discussionmentioning

confidence: 57%

Differential effects of conjugated linoleic acid isomers on macrophage glycerophospholipid metabolism

Ecker

Liebisch

Scherer

et al. 2010

Journal of Lipid Research

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This article is available online at http://www.jlr.org ( c9,. Many CLA isomers have been described; however, the major isomer occurring in meat and dairy products is c9,t11 -CLA ( 2-4 ). It is produced in the rumen through microbial biohydrogenation of linoleic acid and in tissues by delta-9 desaturation of rumen-derived transvaccenic acid ( t11 -FA 18:1) ( 5 ). In contrast, t9,t11 -CLA is the predominant isomer found in dietary oils, as it is generated during partial hydrogenation of vegetable oils and oil refi ning ( 6, 7 ). Several data from in vitro and animal studies show that dietary CLAs are benefi cial and infl uence the progression of several diseases, including cardiovascular and infl ammatory diseases and cancer ( 8-11 ).We have previously reported that two isomers in particular, c9,t11 -and t9,t11 -CLA, have specifi c and even contrasting effects on gene expression associated with lipid metabolism of human macrophages ( 12, 13 ). Concerning CLA metabolism, it has been shown that c9,t11 -CLA incorporates into phospholipids of leukemia cells and can be found in plasma and cellular lipids of healthy men supplemented with a diet enriched with this CLA isomer ( 14, 15 ). However, so far the effects of c9,t11 -CLA on individual phospholipid classes, phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS), and its cellular distribution are not precisely described, and data on the metabolism of the t9,t11 -CLA isomer are completely unavailable.Therefore we investigated c9,t11 -CLA and t9,t11 -CLA metabolism by quantitative lipid mass spectrometry. As a cellular model, human primary monocyte-derived macrophages were chosen because these cells are highly active with respect to fatty acid and phospholipid metabolism ( 16 ). Moreover macrophages, which are multifunctional cells present in all tissues of the human body, play important roles in several metabolic diseases, including atheroAbstract Conjugated linoleic acids (CLA) are dietary fatty acids. Whereas cis-9,trans-11-(c9,t11)-CLA can be found in meat and dairy products, trans-9,trans-11-(t9,t11) -CLA is a constituent of vegetable oils. Previous studies showed that these two isomers activate different nuclear receptors and, thus, expression of genes related to lipid metabolism. Here we show that these CLA isomers are differentially elongated and desaturated in primary monocyte-derived macrophages isolated from healthy volunteers by using gas chromatographymass spectrometry (GC-MS). We further demonstrate that c9,t11 -CLA incorporates in phosphatidylcholine (PC) and phosphatidylethanolamine (PE) species and activates de novo glycerophospholipid synthesis by quantitative electrospray ionization-tandem mass spectrometry (ESI-MS/MS). c9,t11 -CLA leads to strong shifts of the species profi les to PC 18:2/18:2 and PE 18:2/18:2, which are due to de novo synthesis and fatty acid remodeling. In contrast, t9,t11 -CLA is preferentially bound to neutral lipids, including triglycerides and cholesterol esters.Taken together our results show that ...

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Section: Discussionmentioning

confidence: 57%

Differential effects of conjugated linoleic acid isomers on macrophage glycerophospholipid metabolism

Ecker

Liebisch

Scherer

et al. 2010

Journal of Lipid Research

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“…In terms of functional impact, these FA have displayed several bioactive properties such as decrease of body fat, increase of lean body mass and protection against muscle catabolism induced by endotoxins [10], mainly in animal models. In well-nourished animals, CLA can be incorporated into tissues [11] and metabolized [12]. By means of different biochemical mechanisms, CLA modulates the concentration of triacylglycerol (TAG) in liver, adipose tissue and plasma [13], regulates the oxidative status [14], affects some enzyme activities [15] and changes the hormonal and mediators milieu [16] in different species.…”

Section: Introductionmentioning

confidence: 99%

Conjugated Linoleic Acid Reduces Hepatic Steatosis and Restores Liver Triacylglycerol Secretion and the Fatty Acid Profile During Protein Repletion in Rats

Andreoli

Illesca

González

et al. 2010

Lipids

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Protein depletion is associated with hepatic steatosis and decreased circulating triacylglycerol (TAG). Since conjugated linoleic acid (CLA) increases lean body mass, protects against muscle catabolism, and modulates lipid metabolism, the aim of this work was to investigate the effects of CLA with two different amounts of dietary fat on the regulation of plasma and hepatic TAG concentration, and its possible connections with changes in fatty acid (FA) profile in plasma, liver and adipose tissue and hepatic oxidative status during protein repletion. Rats were fed a low protein diet (14 days) and then a protein repletion diet (30 days), supplemented or not with CLA, containing 7% (w/w) or 20% (w/w) of fat. Hepatic TAG secretion and removal by muscle and adipose tissue lipoprotein lipase, FA profile and liver oxidative status were evaluated. Protein depletion affected hepatic TAG secretion and peripheral removal, decreasing plasma and increasing liver TAG concentration, whereas protein repletion with CLA improved these abnormalities independently of the amount of dietary fat by increasing hepatic TAG secretion. This prevention in the absence of CLA was not observed. CLA was incorporated in plasma and tissues (adipose > liver > plasma, and c9,t11-CLA > t10,c12-CLA), accompanied by alterations in FA composition, mainly in adipose tissue. The hepatic oxidative stress was overcome by protein repletion. CLA had a beneficial impact on TAG metabolism in protein repleted animals, preventing hepatic steatosis through higher hepatic TAG secretion.

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“…The oxidation rate in mitochondria present in rat liver homogenates was higher for t10,c12-CLA than for c9,t11-CLA [23]. In peroxisomes, t10,c12 and c9,t11 isomers were metabolized at a different rate, resulting in a much higher proportion of the shortened metabolite from t10,c12 than from c9,t11 [24]. Thus, the higher proportion of c9,t11-CLA in tissues may be explained by a faster metabolism of the t10,c12 isomer.…”

Section: Discussionmentioning

confidence: 99%