Search results for "Linoleic Acids"
showing 10 items of 30 documents
Endurance Exercise and Conjugated Linoleic Acid (CLA) Supplementation Up-Regulate CYP17A1 and Stimulate Testosterone Biosynthesis
2013
A new role for fat supplements, in particular conjugated linoleic acid (CLA), has been delineated in steroidogenesis, although the underlying molecular mechanisms have not yet been elucidated. The aims of the present study were to identify the pathway stimulated by CLA supplementation using a cell culture model and to determine whether this same pathway is also stimulated in vivo by CLA supplementation associated with exercise. In vitro, Leydig tumour rat cells (R2C) supplemented with different concentrations of CLA exhibited increasing testosterone biosynthesis accompanied by increasing levels of CYP17A1 mRNA and protein. In vivo, trained mice showed an increase in free plasma testosterone…
Effects of Conjugated Linoleic Acid and Endurance Training on Peripheral Blood and Bone Marrow of Trained Mice
2007
Fat supplements, especially conjugated linoleic acid (CLA), are increasingly popular ergogenic aids among endurance athletes. To evaluate the importance of fat supplementation in the practice of endurance sports, we investigated the effects of CLA supplementation on body weight, muscle hypertrophy, peripheral blood composition, and bone marrow composition in healthy, young, endurance-trained mice. Young, healthy mice were subdivided into control, trained, and treated groups, according to their running attitudes. Training was performed over a period of 6 weeks on a treadmill, at a gradually increasing duration and speed. CLA-treated groups were gavaged with 0.425 mg x d(-1) CLA supplement fo…
Effect of low levels of dietary fish oil on fatty acid desaturation and tissue fatty acids in obese and lean rats
1995
The effect of very low levels of dietary long-chain n-3 fatty acids on delta 6 desaturation of linoleic acid (18:2n-6) and alpha-linolenic acid (18:3n-3), and on delta 5 desaturation of dihomo-gamma-linolenic acid (20:3n-6), in liver microsomes and its influence on tissue fatty acids were examined in obese and lean Zucker rats and in Wistar rats. Animals fed for 12 wk a balanced diet containing ca. 200 mg of long-chain polyunsaturated n-3 fatty acids per 100 g of diet were compared to those fed the same amount of alpha-linolenic acid. Low amounts of long-chain n-3 fatty acids greatly inhibited delta 6 desaturation of 18:2n-6 and delta 5 desaturation of 20:3n-6, while delta 6 desaturation of…
Hepatic steatosis is not due to impaired fatty acid oxidation capacities in C57BL/6J mice fed the conjugated trans-10,cis-12-isomer of linoleic acid.
2004
Decreased body fat mass and liver steatosis have been reported in mice fed diets containing the conjugated linoleic acid trans-10,cis-12-C18:2 (CLA2), but not in those fed diets containing cis-9,trans-11-C18:2 (CLA1). Because the decrease in fatty acid (FA) oxidation may cause fat accumulation, we questioned whether the effects of both CLAs on enzyme activities and mRNA expression were related to liver FA oxidation. To address this question, 7-wk-old male C57BL/6J mice were fed for 4 wk a diet supplemented with 1% CLA1, CLA2, or cis-9-C18:1 (control) esterified as triacylglycerols. In CLA2-fed mice, the proportions of CLA2 in the total FA of liver lipids were substantially lower than those …
Liver carbohydrate and lipid metabolism of insulin-deficient mice is altered by trans-10, cis-12 conjugated linoleic acid.
2009
Feeding mice the trans-10, cis-12 (t10c12) conjugated linoleic acid (CLA) isomer is associated with lipodystrophy, insulin resistance, hyperinsulinemia, and liver steatosis. It has been hypothesized that CLA-induced liver steatosis is the result of increased hepatic lipogenesis stimulated by high insulin levels. We studied the effects of a 12-d t10c12CLA treatment (1 g/100 g diet) on liver carbohydrate and lipid metabolism in control and streptozotocin (STZ)-injected mice. STZ mice were characterized by insulin deficiency, hypertriglyceridemia, and depletion of liver triglyceride and glycogen. Remarkably, feeding t10c12CLA to diabetic mice (STZ-CLA) normalized these variables. Reconstitutio…
Do Fat Supplements Increase Physical Performance?
2013
Fish oil and conjugated linoleic acid (CLA) belong to a popular class of food supplements known as "fat supplements", which are claimed to reduce muscle glycogen breakdown, reduce body mass, as well as reduce muscle damage and inflammatory responses. Sport athletes consume fish oil and CLA mainly to increase lean body mass and reduce body fat. Recent evidence indicates that this kind of supplementation may have other side-effects and a new role has been identified in steroidogenensis. Preliminary findings demonstrate that fish oil and CLA may induce a physiological increase in testosterone synthesis. The aim of this review is to describe the effects of fish oil and CLA on physical performan…
Trans-10, cis-12 conjugated linoleic acid induced cell death in human colon cancer cells through reactive oxygen species-mediated ER stress
2013
Dietary conjugated linoleic acids (CLA) are fatty acid isomers with anticancer activities produced naturally in ruminants or from vegetable oil processing. The anticancer effects of CLA differ upon the cancer origin and the CLA isomers. In this study, we carried out to precise the effects of CLA isomers, c9,t11 and t10,c12 CLA, on mechanisms of cell death induction in colon cancer cells. We first showed that only t10,c12 CLA treatment (25 and 50μM) for 72h triggered apoptosis in colon cancer cells without affecting viability of normal-derived colon epithelial cells. Exposure of colon cancer cells to t10,c12 CLA activated ER stress characterized by induction of eIF2α phoshorylation, splicing…
Toxicity of fatty acid hydroperoxides towards Yarrowia lipolytica: Implication of their membrane fluidizing action
2007
Abstract Linoleic acid hydroperoxide (HPOD), substrate of hydroperoxide lyase, an enzyme of the lipoxygenase pathway, can be transformed into many aromatic compounds, the so-called “green notes”. The presence of linoleic acid hydroperoxide in the culture medium of Yarrowia lipolytica, the yeast expressing the cloned hydroperoxide lyase of green bell pepper, undoubtedly exerted an inhibition on the growth and a toxic effect with 90% of yeast cells died after 120 min of exposition in 100 mM HPOD solution. The increase in cell membrane fluidity evaluated by measuring fluorescence generalized polarization with the increasing concentration of HPOD in the medium confirmed the fluidizing action of…
Isomerization of 9c11t/10t12c CLA in Triacylglycerols
2010
Published version of an article in the journal: Lipids . The original publication is available at Spingerlink. http://dx.doi.org/10.1007/s11745-010-3452-x Isomers of conjugated linoleic acid from 7t9c through 12t14t can be induced by thermal treatment of triacylglycerol samples of 9c11t or 10t12c fatty acids in glass tubes. The formation of conjugated linoleic acids (CLAs) has been observed during thermal induction of the above-mentioned triacylglycerols at 250, 280 and 320A degrees C. The concentrations of isomers formed in the mixture varied depending on the temperature and duration of the heating experiments. The objective of this study was to find a suitable thermal induction temperatur…
Quantitative separation of Trichoderma lipid classes on a bonded phase column.
1992
Bond Elut aminopropyl columns were used to purify the different lipid classes of Trichoderma harzianum and Trichoderma viride. This methodology permitted good separation of the fungal lipid classes in less time than traditional techniques. The incorporation of [1 (14)C]linoleic acid into neutral lipids, free fatty acids and phospholipids was quantified for both strains. The fatty acid profile of the different lipid classes of these fungal strains was determined as a function of culture time.