scholarly journals trans-10, cis-12 Conjugated linoleic acid inhibits lipoprotein lipase but increases the activity of lipogenic enzymes in adipose tissue from hamsters fed an atherogenic diet

2006 ◽  
Vol 95 (6) ◽  
pp. 1112-1119 ◽  
Author(s):  
Amaia Zabala ◽  
Itziar Churruca ◽  
Alfredo Fernández-Quintela ◽  
Víctor M. Rodríguez ◽  
M. Teresa Macarulla ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Linoleic Acid ◽  
Food Intake ◽  
Lipoprotein Lipase ◽  
Body Fat ◽  
Enzyme Activities ◽  
Serum Insulin ◽  
Mrna Levels ◽  
Lipogenic Enzyme ◽  
Lipogenic Enzymes

The aim of the present work was to investigate the effects of trans-10,cis-12conjugated linoleic acid (CLA) on the activity and expression of lipogenic enzymes and lipoprotein lipase (LPL), as well as on the expression of transcriptional factors controlling these enzymes, in adipose tissue from hamsters, and to evaluate the involvement of these changes in the body fat-reducing effect of this CLA isomer. Thirty male hamsters were divided into three groups and fed atherogenic diets supplemented with 0 (linoleic group), 5 or 10g trans-10,cis-12CLA/kg diet, for 6 weeks. Body and adipose tissue weights, food intake and serum insulin were measured. Total and heparin-releasable LPL and lipogenic enzyme activities (acetyl-CoA carboxylase (ACC); fatty acid synthase (FAS); glucose-6-phosphate dehydrogenase (G6PDH); and malic enzyme (ME)) were assessed. ACC, FAS, LPL, sterolregulatory element-binding proteins (SREBP-1a), SREBP-1c and PPARγ mRNA levels were alsodetermined by real-time PCR. CLA did not modify food intake, body weight and serum insulin level. CLA feeding reduced adipose tissue weight, LPL activity and expression, and increased lipogenic enzyme activities, despite a significant reduction in ACC and FAS mRNA levels. The expression of the three transcriptional factors analysed (SREBP-1a, SREBP-1c and PPARγ) wasalso reduced. These results appear to provide a framework for partially understanding the reduction in body fat induced by CLA. Inhibition of LPL activity seems to be an important mechanism underlying body fat reduction in hamsters. Further research is needed to better characterizethe effects of CLA on lipogenesis and the role of these effects in CLA action.

Effects of isoenergetic barley grain and alfalfa pellet diets on in vitro lipogenesis and lipogenic enzyme activities in subcutaneous adipose tissue from sheep

1997 ◽  
Vol 77 (1) ◽  
pp. 173-175 ◽  
Author(s):  
E. K. Okine ◽  
P. F. Arthur
Keyword(s):  
Adipose Tissue ◽  
Enzyme Activities ◽  
Subcutaneous Adipose Tissue ◽  
Barley Grain ◽  
Lipogenic Enzyme ◽  
Acetyl Coa Carboxylase ◽  
Lipogenic Enzymes ◽  
Acetyl Coa ◽  
Subcutaneous Adipose

The effects of feeding isoenergetic barley grain or alfalfa pellets on in vitro lipogenesis, palmitate esterification, and lipogenic enzymes activities in biopsy samples of subcutaneous adipose tissue in 10 ewes were studied. Acetyl CoA carboxylase and FAS activities and rate of esterification were 52, 38, and 88%, respectively, higher (P < 0.05) in subcutaneous adipose of ewes fed the concentrate versus those fed the roughage diet. Key words: Isoenergetic, adipose tissue, acetyl CoA carboxylase

Lipogenic enzyme activities and mRNA in rat adipose tissue at weaning

1990 ◽  
Vol 258 (1) ◽  
pp. E126-E133 ◽  
Author(s):  
C. Coupe ◽  
D. Perdereau ◽  
P. Ferre ◽  
Y. Hitier ◽  
M. Narkewicz ◽  
...  
Keyword(s):  
Gene Expression ◽  
Adipose Tissue ◽  
Enzyme Activities ◽  
Plasma Insulin ◽  
Regulation Of Gene Expression ◽  
Fatty Acid Synthetase ◽  
Lipogenic Enzyme ◽  
Lipogenic Enzymes ◽  
Suckling Rats ◽  
Force Feeding

The activities and mRNA concentrations of two lipogenic enzymes, fatty acid synthetase and acetyl-CoA carboxylase, and one enzyme involved in glyceroneogenesis, phosphoenolpyruvate carboxykinase (PEPCK), were measured in rat white adipose tissue during the suckling-weaning transition. Activities and mRNA concentrations of lipogenic enzymes were low in suckling rats, whereas activity and mRNA concentration of PEPCK were high. At weaning to a high-carbohydrate diet, the rapid increase in lipogenic enzymes mRNA (10- to 20-fold) and decrease in PEPCK mRNA (10-fold) were followed by parallel changes in enzyme activities. In contrast, weaning to a high-fat diet prevented these modifications. Force feeding suckling rats with carbohydrates induced a rise in blood glucose and plasma insulin concentrations. During these experiments, mRNA concentrations increased 10- to 20-fold for lipogenic enzymes and decreased 5-fold for PEPCK in less than 6 h, whereas all enzyme activities did not vary. This suggests a pretranslational regulation of gene expression. Force feeding suckling rats with a mixture of fat devoid of carbohydrate induced a slight increase in plasma insulin concentration and a fall in PEPCK mRNA but was not accompanied by a rise in lipogenic enzyme mRNAs. This suggested that insulin is a prime regulator of PEPCK gene expression, whereas glucose and insulin act synergistically in the regulation of lipogenic enzyme gene expression.

Lipoprotein lipase and lipogenic enzyme activities in adipose tissue from rats fed different lipid sources

2001 ◽  
Vol 57 (3) ◽  
pp. 245-254 ◽  
Author(s):  
V. M. Rodríguez ◽  
M. T. Macarulla ◽  
M. Chávarri ◽  
D. Durán ◽  
M. P. Portillo
Keyword(s):  
Adipose Tissue ◽  
Lipoprotein Lipase ◽  
Enzyme Activities ◽  
Lipogenic Enzyme

Loss of body fat in lean parabiotic partners of ob/ob mice

1997 ◽  
Vol 272 (6) ◽  
pp. R1809-R1815 ◽  
Author(s):  
R. B. Harris
Keyword(s):  
Food Intake ◽  
Mrna Expression ◽  
Body Fat ◽  
Rectal Temperature ◽  
Serum Insulin ◽  
Serum Leptin ◽  
Leptin Expression

The objective of this experiment was to confirm whether changes in serum leptin and leptin expression were consistent with it being the "lipostatic" factor implicated by earlier parabiosis studies. Lean (+/?) and obese (ob/ob) female C57B1/6J-ob mice were parabiosed (lean-ob/ob) at 7 wk of age. Controls were ob/ob-ob/ob and lean-lean pairs, and single lean and ob/ob mice. Pairs were maintained for 50 days. In ob/ob members of lean-ob/ob pairs serum insulin was normalized, food intake was suppressed, and body fat was reduced by 14%. Lean partners of ob/ob mice had a reduced rectal temperature and experienced a 37% reduction in body fat. Despite loss of fat, serum leptin and adipose leptin mRNA expression were unchanged in lean partners of ob/ob mice. These results suggest that, in lean-ob/ob parabiotic pairs, the ob/ob mouse responds to leptin originating in the lean parabiont, whereas the lean partner responds to a circulating signal, originating in the ob/ob mouse, that maintains leptin expression at inappropriate levels for the degree of adiposity of the lean animal.

Diurnal rhythms and effects of fasting and refeeding on rat adipose tissue lipoprotein lipase

1996 ◽  
Vol 271 (6) ◽  
pp. E1092-E1097 ◽  
Author(s):  
M. Bergo ◽  
G. Olivecrona ◽  
T. Olivecrona
Keyword(s):  
Adipose Tissue ◽  
Lipoprotein Lipase ◽  
Specific Activity ◽  
Early Morning ◽  
Diurnal Rhythms ◽  
Mrna Levels ◽  
Short Term ◽  
Early Afternoon ◽  
Rat Adipose Tissue ◽  
Adipose Tissue Lipoprotein Lipase

The activity of lipoprotein lipase (LPL) in adipose tissue is modulated by changes in the nutritional status. We have measured LPL activity, mass, and mRNA levels in rat adipose tissue during normal feeding cycles, during short- and long-term fasting, and during refeeding after fasting. LPL activity displayed a diurnal rhythm. The activity was highest during the night and early morning, decreased to a minimum during the early afternoon, and then increased again. These changes corresponded to the feeding pattern. The increases and/or decreases resulted from changes in LPL synthetic rate compounded by posttranslational mechanisms. During short-term fasting, LPL specific activity decreased to < 30% of control. The specific activity was restored within 4 h by refeeding. On longer fasting, LPL mRNA decreased. This became significant from 36 h. On refeeding, it took 12 h to restore the mRNA levels, whereas tissue LPL activity and mass could not be fully restored by 36 h of refeeding. These data show that LPL activity during short-term fasting is regulated posttranscriptionally, which allows for quick upregulation after refeeding. On longer fasting, other mechanisms affecting LPL transcription and synthesis come into play, and upregulation after refeeding is slowed down.

scholarly journals Adipose-tissue lipoprotein lipase activity and cellularity in the genetically obese Zucker rat (fa/fa) (Short Communication)

1973 ◽  
Vol 132 (3) ◽  
pp. 633-635 ◽  
Author(s):  
P. de Gasquet ◽  
E. Péquignot ◽  
D. Lemonnier ◽  
A. Alexiu
Keyword(s):  
Adipose Tissue ◽  
Surface Area ◽  
Lipoprotein Lipase ◽  
Lipase Activity ◽  
Enzyme Activities ◽  
Short Communication ◽  
Zucker Rat ◽  
Lipoprotein Lipase Activity ◽  
Obese Zucker Rat ◽  
Adipose Tissue Lipoprotein Lipase

The lipoprotein lipase activity per adipocyte was increased in the genetically obese rat (fa/fa). However, there was no difference between obese and lean animals when the enzyme activities were related to adipocyte surface area. The possible implications of the findings are discussed.

Enhanced adipose tissue lipoprotein lipase activity in detrained rats: independent of changes in food intake

1994 ◽  
Vol 77 (6) ◽  
pp. 2564-2571 ◽  
Author(s):  
E. V. Lambert ◽  
G. Wooding ◽  
M. I. Lambert ◽  
J. H. Koeslag ◽  
T. D. Noakes
Keyword(s):  
Adipose Tissue ◽  
Food Intake ◽  
Exercise Training ◽  
Lipoprotein Lipase ◽  
Energy Intake ◽  
Body Mass ◽  
Exhaustive Exercise ◽  
Sedentary Control ◽  
Food Energy ◽  
Adipose Tissue Lipoprotein Lipase

Short-term detraining has been characterized by increased body mass and rapid body fat accretion. However, detraining has also been associated with increased food intake, especially in rats genetically predisposed to obesity. Thus, it has been difficult to separate refeeding effects from alterations resulting from the cessation of exercise training. In the present study, the in vitro activity of adipose tissue lipoprotein lipase (ATLPL) was measured in freely running wheel-trained rats and rats that had stopped training for 1, 2, or 3 days or 1 or 2 wk, respectively. Heparin-releasable ATLPL activity was measured at rest and after acute exhaustive exercise. Feeding efficiency (change in body mass/kJ ingested energy), fat pad mass, and adipocyte size were also measured. The rate of weight gain in 1- and 2-wk detrained rats was significantly higher than that of sedentary control or trained rats (P < 0.05). Feeding efficiency was also higher in 1-wk detrained rats than in all other groups (P < 0.005). However, food energy intake was not different between trained rats, 1- and 2-wk detrained rats, or sedentary control rats. ATLPL activity in all groups was highest after acute exhaustive exercise. ATLPL activity in 1-wk detrained rats was nearly threefold higher compared with that in trained rats (P < 0.005) and was not different from that of sedentary control rats. These results suggest that the cessation of exercise training causes an enhanced capacity for lipogenesis independent of changes in food energy intake or the acute effects of the last bout of exercise.

Lipogenic Enzymes of Rat Liver and Adipose Tissue. Dietary Variations and Effect of Polychlorinated Biphenyls

1994 ◽  
Vol 49 (9-10) ◽  
pp. 665-678 ◽  
Author(s):  
Meinrad Boll ◽  
Lutz W. D. Weber ◽  
Andreas Stampfl ◽  
Burkhard Messner
Keyword(s):  
Adipose Tissue ◽  
Polychlorinated Biphenyls ◽  
Enzyme Activities ◽  
Time Course ◽  
Fatty Acid Synthase ◽  
Lipogenic Enzymes ◽  
Brown Adipose ◽  
Cleavage Enzyme ◽  
Order Of Magnitude ◽  
Glucose 6 Phosphate Dehydrogenase

Abstract The lipogenic enzymes fatty acid synthase (FAS; EC 2.3.1.85), citrate cleavage enzyme (CCE; EC 4.1.3.8), malic enzyme (ME; EC 1.1.1.40), glucose-6-phosphate dehydrogenase (G6PDH; EC 1.1.1.49) and 6-phosphogluconate dehydrogenase (PGDH; EC 1.1.1.44) were investigated in liver and in brown adipose tissue (BAT) of Wistar rats under various dietary conditions and in the presence of 15 to 250 ppm (approximately 0.045-0.75 μmol/kg chow) polychlorinated biphenyls (PCBs).In response to refeeding starved animals, enzyme activities in both tissues increased to above normal levels and thereafter exhibited pronounced oscillations of their activities. The extent of increase depended on the carbohydrate and fat content of the diet. The lipogenic enzymes could be grouped in two categories according to their sensitivity to dietary carbohydrate: FAS and CCE responded faster to smaller changes in dietary composition, while ME, G6PDH and PGDH required larger changes and more time to respond.Diet-induced alterations of enzyme activities were of the same order of magnitude in liver and BAT. They were age-dependent, being more pronounced in young animals. Independent of the type of dietary manipulations, activities changed in a coordinate fashion, i.e., the changes of the activities of all 5 enzymes occurred at similar ratios to each other with an identical time course.Feeding PCB-containing diets resulted in a considerable increase of the activities of the lipogenic enzymes in liver, which was significantly greater with ME, G 6PD H and PGDH. The effect was dose-dependent but transient. In liver the response to PCB feeding was iden­tical in male and female animals, whereas in BAT lipogenic activities increased in females, but decreased in males.Refeeding starved animals with a PCB-containing diet led to an additional stimulation of the normal refeeding-induced increase of the enzyme activities in liver and BAT. This PCB-induced increase was 2-fold for FAS and CCE, but up to 15-fold for the other enzymes. All PCB-induced effects were significantly less pronounced in old than in young animals.In primary hepatocytes activities increased in hormone-free medium in the presence of PCBs. While activity was induced in insuline-and triiodothyronine-containing medium, this increase was significantly greater with PCBs present.

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