Biomedical subjects

Jean-Michel Chardigny

Publications and source records attributed to Jean-Michel Chardigny.

At least 19 recordsLinked to original sources

PubMed2006

Dietary conjugated linoleic acid has limited effects on tissue protein anabolism in sedentary and exercising adult rats.

The effects of conjugated linoleic acid isomers (CLA) and endurance training on lean body mass are expected to result from their action on tissue protein metabolism. The aim of this study was to analyze their effects on protein metabolism in 2 muscles, the small intestine and liver of adult rats. Four-month-old male Wistar rats were fed diets containing either no CLA, cis-9, trans-11 CLA isomer (1 g.100 g(-1)), trans-10, cis-12 CLA isomer (1 g.100 g(-1)) or both isomers (1 g.100 g(-1) each) for 6 weeks. Half of the rats were subjected to endurance training by running on a treadmill. At the end of this period, the rats were injected with a flooding dose of (13)C-valine to determine protein synthesis rates in the post-absorptive (experiment 1) and in the post-prandial (experiment 2) states. No effect of CLA or endurance training were detected in the small intestine. Training reduced food intake and protein synthesis rates in the liver but no effect was found on the protein synthesis rates in muscles. In the post-absorptive state, protein synthesis rate was increased by feeding the trans-10, cis-12 CLA isomer alone in the liver (+9%) or in combination with the cis-9, trans-11 isomer in the gastrocnemius (+30%), mostly in sedentary rats. In the post-prandial state, the cis-9, trans-11 CLA isomer tended to reduce the protein synthesis rate in the gastrocnemius muscle. However, no effect of CLA was found on muscle protein amounts. In conclusion, CLA isomers would have limited but differential effects on tissue protein metabolism in adult rats.

Animals↗

PubMed2006

Phospholipid fatty acid pattern and D-glucose metabolism in muscles from omega3 fatty acid-depleted rats.

A depletion in long-chain polyunsaturated omega3 fatty acids may affect fuel homeostasis. In such a perspective, the present study deals mainly with the in vitro fate of D-[U-(14)C]glucose in hemidiaphragms, stretched soleus and plantaris muscle pieces obtained from normal and omega3-depleted rats (second generation) and incubated in the absence or presence of insulin. When so required, the omega3-depleted rats were injected 120 min before sacrifice with either a omega3 fatty acid-rich medium-chain triglyceride:fish oil emulsion (FO) or a control medium-chain triglyceride:olive oil emulsion (OO). The content of the soleus muscle in long-chain polyunsaturated omega3 fatty acids was severely decreased in the omega3-depleted rats, and modestly albeit significantly increased after injection of FO to these animals. In stretched soleus muscles from OO-injected omega3-depleted rats, the absolute values for glycogen synthesis measured in the absence or presence of insulin were about twice higher than in normal animals. In the OO-injected omega3-depleted rats, insulin augmented the output of (14)C-labelled amino acids, whilst such was not the case in normal animals. These and other findings suggest a lower catabolism of D-glucose relative to the anabolic process of glycogen synthesis and a lower availability of endogenous amino acids in the muscles of omega3-depleted rats, as compared to those of control animals. The prior injection of FO to the omega3-depleted rats restored a normal value for the paired ratio between the output of (14)C-labelled amino acids and acidic metabolites, but further increased glycogen net synthesis. It is proposed, therefore, that the perturbation of d-glucose metabolism in muscles from omega3-depleted rats involves a multifactorial determinism, only some of the concerned factors being susceptible to rapid correction after enrichment of cell phospholipids in long-chain polyunsaturated omega3 fatty acids.

Animals↗

PubMed2006

The retina is more susceptible than the brain and the liver to the incorporation of trans isomers of DHA in rats consuming trans isomers of alpha-linolenic acid.

Trans polyunsaturated fatty acids are formed during heat treatments of vegetable oils from polyunsaturated fatty acids containing cis double bonds. After dietary intake, they are distributed in the body and are incorporated into nervous tissues including the retina. Since nervous tissues are known to be rich in n-3 fatty acids such as docosahexaenoic acid (DHA), we studied the ability of the retina and the brain to incorporate trans isomers of DHA formed in vivo from the dietary precursor trans alpha-linolenic acid. Wistar rats were fed with trans isomers of alpha-linolenic acid for 21 months. A linear incorporation of trans DHA and a decrease in cis DHA was observed in the retina, whereas no major changes were observed in the brain. In parallel to the modifications in retinal cis and trans DHA levels, the retinal functionality evaluated by the electroretinogram showed defects in animals that consumed trans alpha-linolenic acid. These results suggest that the mechanisms leading to the incorporation of cis and trans fatty acids are quite different in the retina when compared to the brain and the liver, the retina being more susceptible to changes in the dietary lipid contribution.

Animals↗

PubMed2006

Upregulation of liver VLDL receptor and FAT/CD36 expression in LDLR-/- apoB100/100 mice fed trans-10,cis-12 conjugated linoleic acid.

This study explores the mechanisms responsible for the fatty liver setup in mice fed trans-10,cis-12 conjugated linoleic acid (t10c12 CLA), hypothesizing that an induction of low density lipoprotein receptor (LDLR) expression is associated with lipid accumulation. To this end, the effects of t10c12 CLA treatment on lipid parameters, serum lipoproteins, and expression of liver lipid receptors were measured in LDLR(-/-) apoB(100/100) mice as a model of human familial hypercholesterolemia itself depleted of LDLR. Mice were fed t10c12 CLA over 2 or 4 weeks. We first observed that the treatment induced liver steatosis, even in the absence of LDLR. Mice treated for 2 weeks exhibited hypertriglyceridemia with high levels of VLDL and HDL, whereas a 4 week treatment inversely induced a reduction of serum triglycerides (TGs), essentially through a decrease in VLDL levels. In the absence of LDLR, the mRNA levels of other proteins, such as VLDL receptor, lipoprotein lipase, and fatty acid translocase, usually not expressed in the liver, were upregulated, suggesting their involvement in the steatosis setup and lipoprotein clearance. The data also suggest that the TG-lowering effect induced by t10c12 CLA treatment was attributable to both the reduction of circulating free fatty acids in response to the severe lipoatrophy and the high capacity of liver to clear off plasma lipids.

Animals↗

PubMed2006

Rationale and design of the TRANSFACT project phase I: a study to assess the effect of the two different dietary sources of trans fatty acids on cardiovascular risk factors in humans.

BACKGROUND: Detrimental effects of consumption of industrial trans fatty acids (TFA) from partially hydrogenated vegetable oils (PHVO) on cardiovascular disease (CVD) risk factors are well documented. However, very little information is available on the effect of natural sources of TFA coming from milk fat, dairy products and ruminant meat. In fact, due to the naturally low level of TFA in milk fat, it is almost impossible to conduct a clinical trial with a limited number of subjects (<200). METHODOLOGY: To compare the effects of industrial and natural dietary sources of TFA, two specific test fats have been designed and produced. A substantial amount of milk fat (130 kg) enriched in TFA has been produced by modification of the cow's diet and selection of cows with the highest TFA content. The level obtained was approximately 4- to 7-fold higher than typically present in milk fat (approximately 20 instead of 3-6 g/100 g of total fatty acids). The control fat is composed of PHVO balanced in saturated fatty acids (lauric, myristic and palmitic). Both experimental fats contain about 20-22% of monounsaturated TFA and the volunteers' daily experimental fat intake (54 g), will represent about 12.0 g/day of TFA or 5.4% of the daily energy (based on 2000 kcal/day). These two test fats have been incorporated into food items and will be provided to 46 healthy subjects under a randomised, double blind, controlled, cross-over design. The primary outcome is high-density lipoprotein cholesterol (HDL-C), which is an independent risk factor for CVD. Other parameters such as low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), and HDL-C level and subclasses will be also to be evaluated. CONCLUSION: We have shown that it is technically feasible to perform a clinical trial on the comparative effects of natural and industrial sources of TFA isomers on CVD risk factors. Results are expected by mid-2006.

Adult↗

PubMed2006

Absorption and metabolism of conjugated alpha-linolenic acid given as free fatty acids or triacylglycerols in rats.

BACKGROUND: Conjugated linoleic acid (CLA) is a group of polyunsaturated fatty acids which have been extensively studied in the past two decades. However, conjugated octadecatrienoic acid such as cis-9,trans-11,cis-15 and cis-9,trans-13,cis-15, recently identified, have not been extensively investigated. This work presents bioavailability and tissue incorporation of a mixture of conjugated octadecatrienoic (CLnA) acids ingested as free fatty acids (FFA) and triacylglycerols (TAG). RESULTS: Male Wistar rats were fed rumenic acid (RA: cis-9,trans-11 18:2) and a CLnA mixture (cis-9,trans-11,cis-15 18:3 and cis-9,trans-13,cis-15 18:3) as FFA and TAG for 8 days. RA and CLnA were both totally absorbed when given as FFA as well as TAG. Both isomers of CLnA as FFA or TAG were incorporated into neutral lipids. Metabolites up to 22:6 conjugated isomers were present in liver and plasma phospholipids of rats fed the CLnA diets. CONCLUSION: Finally, CLnA are as well absorbed as RA in vivo and their incorporation into tissues and bioconversion are similar when ingested as FFA or as TAG.

Journal Article↗

PubMed2006

Beef conjugated linoleic acid isomers reduce human cancer cell growth even when associated with other beef fatty acids.

Although many data are available concerning anticarcinogenic effects of industrial conjugated linoleic acid (CLA), few studies have reported the antitumour properties of CLA mixtures originating from ruminant products. The aim of the present study was to investigate the in vitro antiproliferative effects of beef CLA mixtures on breast, lung, colon, melanoma and ovarian human cancer cell lines. For this purpose, four fatty acid (FA) extracts prepared from beef lipid and varying in their CLA composition, their corresponding purified CLA-enriched fractions, and mixtures of pure synthetic CLA, the composition of which reproduced that of the four selected beef samples, were tested on cancer cell lines. Cancer cells were exposed for 48 h to medium containing 100 microm-FA and their proliferation was determined by quantifying cellular DNA content (Hoechst 33342 dye). Compared with cells incubated without FA, the number of cancer cells was reduced from 25 to 67 % (P<0.0001) following FA treatment. Antiproliferative effects of CLA mixtures varied in magnitude according to the source of FA, the CLA composition and the cell lines. CLA mixtures naturally present in beef inhibited the proliferation of human cancer cell lines, a high content in cis-trans isomers allowing the most important antiproliferative effect. Beef total FA exhibited a greater growth-inhibitory activity than their corresponding CLA-enriched fractions. These results suggested that either beef FA other than beef CLA could possess antiproliferative properties and/or the existence of complementary effects of non-conjugated FA and CLA, which could favour the antiproliferative properties of beef total FA.

Animals↗

PubMed2006

Pancreatic islet function in omega3 fatty acid-depleted rats: Glucose metabolism and nutrient-stimulated insulin release.

In order to gain information on the determinism of the perturbation of fuel homeostasis in situations characterized by a depletion in long-chain polyunsaturated omega3 fatty acids (omega3), the metabolic and hormonal status of omega3-depleted rats (second generation) was examined. When required, these rats were injected intravenously 120 min before sacrifice with a novel medium-chain triglyceride-fish oil emulsion able to provoke a rapid and sustained increase of the omega3 content in cell phospholipids. The measurement of plasma glucose, insulin, phospholipid, triglyceride, and unesterified fatty acid concentration indicated modest insulin resistance in the omega3-depleted rats. The plasma triglyceride and phospholipid concentrations were decreased in the omega3-depleted rats with abnormally low contribution of omega3 in both circulating and pancreatic islet lipids. The protein, insulin, and lipid content of the islets, as well as their intracellular and extracellular spaces, were little affected in the omega3-depleted rats. The metabolism of D-glucose in the islets of omega3-depleted rats was characterized by a lesser increase in D-[5-3H]glucose utilization and D-[U-14C]glucose oxidation in response to a given rise in hexose concentration and an abnormally low ratio between D-glucose oxidation and utilization. These abnormalities could be linked to an increased metabolism of endogenous fatty acids with resulting alteration of glucokinase kinetics. The release of insulin evoked by D-glucose, at a close-to-physiological concentration (8.3 mM), was increased in the omega3-depleted rats, this being considered as consistent with their insulin resistance. Relative to such a release, that evoked by a further rise in D-glucose concentration or by non-glucidic nutrients was abnormally high in omega3-depleted rats, and restored to a normal level after of the intravenous injection of the omega3-rich medium-chain triglyceride-fish oil emulsion. Because the latter procedure failed to correct the perturbation of D-glucose metabolism in the islets of omega3-depleted rats, it is proposed that the anomalies in the secretory behaviour of islets in terms of their response to an increase in hexose concentration or non-nutrient secretagogues is mainly attributable to alteration in K+ and Ca2+ handling, as indeed recently documented in separate experiments.

Animals↗

PubMed2006

Effect of dietary supply of butters rich either in trans-10-18 : 1 or in trans-11-18 : 1 plus cis-9, trans-11-18 : 2 on rabbit adipose tissue and liver lipogenic activities.

Experimental butters with a high content of trans-18 : 1 fatty acids and/or cis-9,trans-11-18 : 2 (rumenic acid; RA) were fed to thirty-six New Zealand White rabbits to investigate their effects on adipose tissue (AT) and liver lipogenic activities. Animals received one of three atherogenic (0.2 % cholesterol) diets containing 12 % butter with either a standard fatty acid composition (rich in saturated fatty acids), rich in trans-10-18 : 1 (T10 diet) or in trans-11-18 : 1 plus RA (T11+ RA diet) for 6 or 12 weeks. The ingestion of butters rich in trans fatty acids and/or RA for 6 weeks had little or no effect on liver and AT lipogenesis. The ingestion for 12 weeks of butter rich in T11+ RA decreased perirenal AT weight, lipogenic enzyme and lipoprotein lipase activities, without affecting liver lipid concentration or lipogenic activities except for a decrease in glycerol-3-phosphate dehydrogenase activity. Similar trends, but of a lower magnitude, were observed in rabbits fed the T10 diet for 12 weeks. Ingestion of the T10 or T11+ RA diets for 6 or 12 weeks had no significant effect on plasma metabolites and hormones except for glucose which increased at 6 weeks in the T10 group. Plasma leptin concentration was positively correlated with AT weight but did not differ between the three diets. In conclusion, the supply of butters rich in either T10 or T11+ RA in an atherogenic diet for 12 weeks decreased rabbit AT lipogenesis, with a more marked effect of the T11+RA diet, but had no effect on liver lipogenesis.

Adipose Tissue↗

PubMed2005

Cis-9, trans- 11 and trans-10, cis-12 conjugated linoleic acid (CLA) do not affect the plasma lipoprotein profile in moderately overweight subjects with LDL phenotype B.

BACKGROUND: Results of a pilot study suggested that cis-9, trans-11 conjugated linoleic acid (CLA) improved LDL phenotype in moderately overweight subjects with LDL phenotype B. OBJECTIVE: Initiated by the results of this pilot study, we have specifically designed a study to test the hypothesis that cis-9, trans-11 conjugated linoleic acid improves LDL phenotype in moderately overweight subjects with LDL phenotype B. Effects on the serum lipid profile, on plasma glucose and insulin concentrations, and on clinical parameters were also examined. DESIGN: Volunteers with LDL phenotype B were divided into three groups consuming daily a drinkable dairy product not enriched with CLA (placebo, n = 34), the same dairy product enriched with 3g c9, t11 CLA (n = 34), or the dairy product enriched with 3g t10, c12 CLA (n = 19) for 13 weeks. RESULTS: Median changes in the proportions of plasma small dense LDL were -2.0% in the control group and -0.1% in the c9, t11 CLA and t10, c12 CLA groups (p = 0.981 for the differences between the groups). c9, t11 CLA or t10, c12 CLA did also not affect serum concentrations of LDL and HDL cholesterol, and of triacylglycerol, and plasma concentrations of glucose and insulin. CONCLUSIONS: In humans with LDL phenotype B, c9, t11 CLA and t10, c12 CLA do not beneficially change risk factors for cardiovascular disease or diabetes.

Adult↗

PubMed2005

In situ hybridization of dihydroxyacetone phosphate acyltransferase, the regulating enzyme involved in plasmalogen biosynthesis.

In situ hybridization can be carried out using different methods. The experimenter has to choose various parameters: the type of tissue fixation, the time of incubation, and the duration of the exposure time. All these parameters are determinant for the sensitivity and the resolution of this technique. This publication of technical aspects described different experiments performed for in situ hybridization on liver tissue. We may conclude on the parameters to optimize each step of the hybridization procedure. Moreover, this technique could be transposed to the brain and applied to little structures with a light expression of DHAP-AT.

Acyltransferases↗

PubMed2005

Metabolites of conjugated isomers of alpha-linolenic acid (CLnA) in the rat.

Rumelenic (cis-9,trans-11,cis-15 18:3) acid is a naturally occurring conjugated isomer of alpha-linolenic acid (CLnA) in milk fat. Metabolism in rats was studied using a synthetic CLnA mixture, composed mainly by equimolar quantities of cis-9,trans-11,cis-15 and cis-9,trans-13,cis-15 CLnA isomers. Their metabolisms were studied by feeding high quantities of CLnA (150 mg/day) for 4 days to rats that had been reared on a fatfree diet for 2 weeks. After this period, animals were sacrificed and liver and epididymal adipose tissue lipids extracted. Six metabolites of the cis-9,trans-11,cis-15 18:3 CLnA isomers were identified as being cis-7,trans-9,cis-13 16:3, cis-11,trans-13,cis-17 20:3, cis-8,cis-11,trans-13,cis-17 20:4, cis-5,cis-8,cis-11,trans-13,cis-17 20:5, cis-7,cis-10,cis-13,trans-15,cis-19 22:5, and cis-4,cis-7,cis-10,cis-13,trans-15,cis-19 22:6 acids. Two metabolites of cis-9,trans-13,cis-15 18:3 CLnA isomer were also identified by GC-MS as being cis-7,trans-11,cis-13 16:3 and cis-5,cis-8,cis-11,trans-15,cis-17 20:5.

Adipose Tissue↗

PubMed2005

Vaccenic acid metabolism in the liver of rat and bovine.

Hepatic metabolism of vaccenic acid (VA), especially its conversion into CLA, was studied in the bovine (ruminant species that synthesizes CLA) and in the rat (model for non-ruminant) by using the in vitro technique of liver explants. Liver tissue samples were collected from fed animals (5 male Wistar rats and 5 Charolais steers) and incubated at 37 degrees C for 17 h under an atmosphere of 95% O2/5% CO2 in medium supplemented with 0.75 mM of FA mixture and with 55 microM [1-14C]VA. VA uptake was about sixfold lower in bovine than in rat liver slices (P< 0.01). For both species, VA that was oxidized to partial oxidation products represented about 20% of VA incorporated by cells. The chemical structure of VA was not modified in bovine liver cells, whereas in rat liver cells, 3.2% of VA was converted into 16:0 and only 0.33% into CLA. The extent of esterification of VA was similar for both animal species (70-80% of incorporated VA). Secretion of VA as part of VLDL particles was very low and similar in rat and bovine liver (around 0.07% of incorporated VA). In conclusion, characteristics of the hepatic metabolism of VA were similar for rat and bovine animals, the liver not being involved in tissue VA conversion into CLA in spite of its high capacity for FA desaturation especially in the rat. This indicates that endogenous synthesis of CLA should take place exclusively in peripheral tissues.

Animals↗

PubMed2005

Effects of a medium-chain triglyceride:fish oil emulsion administered intravenously to omega3 fatty acid-depleted rats on cationic fluxes in aortic rings.

The handling of 45Ca and 86Rb by aortic rings obtained from rats depleted in long-chain polyunsaturated omega3 fatty acids (second generation) was examined in vitro over 10 to 60 min incubation at either increasing concentrations of extracellular K+ (5, 3 and 60 mM) in the case of 45Ca net uptake or in the absence and presence of ouabain (50 microM) in the case of 86Rb uptake. The omega3-depleted rats were injected intravenously 120 min before sacrifice with 1.0 ml of either an omega3 fatty acid-rich medium-chain triglyceride:fish oil emulsion (MCT:FO) or a control medium-chain triglyceride:olive oil emulsion (MCT:OO). In the MCT:OO-injected rats, the rise in extracellular K+ concentration failed to stimulate 45Ca net uptake, whilst the prior injection of the MCT:FO emulsion restored the expected increase in 45Ca net uptake by aortic rings exposed to 60 mM K+. The absolute value for 86Rb net uptake after 10 or 60 min incubation and whether in the absence or presence of ouabain, which significantly decreased the uptake of 86Rb+ after 60 min incubation, only represented in the MCT:FO-injected rats 63.1+/-3.8% of the mean corresponding values found in MCT:OO-injected animals. These findings are consistent with the view that activity of cationic channels, such as the voltage-sensitive Ca2+ channel, the outflow of Ca2+ as mediated by either Na+-Ca2+ countertransport or a Ca2+-ATPase, the activity of Na+,K+-ATPase and the modality of K+ inflow by an oubain-resistant modality are all affected in aortic cells by the content of long-chain polyunsaturated omega3 fatty acids in membrane phospholipids.

Animals↗

PubMed2004

Isomers of conjugated linoleic acid decrease plasma lipids and stimulate adipose tissue lipogenesis without changing adipose weight in post-prandial adult sedentary or trained Wistar rat.

The respective effects and interactions of supplementation with two conjugated linoleic acid (CLA) isomers and exercise on plasma metabolic profile, activity of lipogenic enzymes and cellularity in two adipose tissue sites, those of the liver and heart, were examined in adult Wistar rats. Rats that were either sedentary or exercise-trained by treadmill running were fed one of four diets: a diet without CLA; a diet with either 1% cis 9, trans 11 CLA or 1% trans 10, cis 12 CLA; or a mixture of both isomers (1% of each) for 6 weeks. We observed that the exercise decreased lipogenic enzyme activities in epididymal and perirenal adipose tissue. Plasma cholesterol, insulin, and leptin concentrations were lower in exercise-trained rats than in sedentary rats. The ingestion of either CLA mixture or the trans 10, cis 12 CLA increased lipogenic enzyme activities in epididymal tissue and more markedly in perirenal adipose tissue, especially in sedentary rats, and without affecting adipose tissue weight or cellularity. A similar effect of trans 10, cis 12 CLA was observed in regard to malic enzyme activity in the liver. In addition, this isomer decreased plasma lipid and urea concentrations and increased plasma 3-hydroxybutyrate levels. The ingestion of cis 9, trans 11 CLA increased fatty acid synthase activity in perirenal adipose tissue in sedentary rats and decreased plasma cholesterol and leptin concentrations. These results show that isomers of CLA decrease plasma lipids and stimulate adipose tissue lipogenesis without changing adipose weight in adult sedentary or exercise-trained rat, thus suggesting a stimulation of adipose tissue turnover.

Adipose Tissue↗

PubMed2004

Influence of manufacturing conditions on the conjugated linoleic acid content and the isomer composition in ripened French Emmental cheese.

In a study of the evolution of conjugated linoleic acid (CLA) during cheese production, the influence of Emmental cheese processing on the CLA content and the CLA isomer composition was evaluated. The use of raw and thermised milk, changes of processing temperature and the effect of propionic acid bacteria (PAB) were investigated. The content of CLA in raw milk was 8.6 +/- 1.9 mg/g fat and in the ripened cheese at 70 d was 8.6 +/- 1.6 mg/g fat, under normal processing conditions. No changes in the CLA content and CLA isomer composition were observed during Emmental cheese manufacturing process. Changes in cooking and moulding temperatures did not influence the CLA content. CLA content of cheese made from microfiltered milk with two different Propionibacterium freudenreichii strains was very close to cheeses made without PAB. CLA levels seem to be stable in this type of dairy product under the conditions examined.

Animals↗

PubMed2004

Cis-9, trans-11 and trans-10, cis-12 conjugated linoleic acid isomers do not modify body composition in adult sedentary or exercised rats.

Dietary CLA isomers were shown to reduce adipose tissues in growing animals, mainly in mice, but their effects in adult animals remain unclear. This study was conducted to determine whether these effects depend on the isomer fed, on physical activity, or on the initial level of body fat. Male Wistar rats (4 mo old) were fed for 6 wk diets containing either no CLA, the cis-9, trans-11 CLA isomer (10 g/kg), the trans-10, cis-12 CLA isomer (10 g/kg), or both isomers (10 g/kg each). Half of the rats were assigned to exercise by treadmill running (1 h/d, 22 m/min). The initial body fat level was normal (12.7%) in a first trial, and high (18.9%) in a second trial. Chemical and anatomical body compositions were determined by chemical analysis and organ dissection. In both trials, the CLA diets, whatever the isomer, had no effect on food intake and body weight changes, on body chemical composition (fat, protein and water contents or gains), or on the body anatomical composition (weights or gains in epididymal and perirenal adipose tissues, in liver and in 4 muscles). There was no interaction between CLA treatment and physical activity. In conclusion, adult male rats do not appear to be responsive to the fat-to-lean partitioning effect of CLA described in growing rats. This was not affected by exercise or initial body fat level.

Animals↗

PubMed2003

Association of liver steatosis with lipid oversecretion and hypotriglyceridaemia in C57BL/6j mice fed trans-10,cis-12-linoleic acid.

Conjugated linoleic acids (CLA) have recently been recognized to reduce body fat and plasma lipids in some animals. This study demonstrated that the steatosis accompanying the fat loss induced by trans-10,cis-12-C(18:2) (CLA2) and not cis-9,trans-11-C(18:2) (CLA1) isomer in C57BL/6j mice was not due to an alteration of the liver lipoprotein production that was even increased. The 3-fold decrease in plasma triacylglycerol contents and the induction of mRNA expression of low-density lipoprotein receptors concomitantly observed in CLA2-fed mice suggested an increase in the lipoprotein clearance at the level of the liver itself. CLA1 feeding produced similar but attenuated effects on triglyceridaemia only.

Animals↗