Response of lipogenic enzymes to overfeeding in liver and adipose tissue of light and heavy breeds of chicks

1978 ◽  
Vol 39 (1) ◽  
pp. 151-157 ◽  
Author(s):  
Niva Shapira ◽  
I. Nir ◽  
P. Budowski
Keyword(s):  
Adipose Tissue ◽  
Fatty Acid Synthetase ◽  
Fat Content ◽  
Acetyl Coa Carboxylase ◽  
Lipogenic Enzymes ◽  
Atp Citrate Lyase ◽  
Phosphogluconate Dehydrogenase ◽  
Citrate Lyase ◽  
Generating Capacity ◽  
Glucose 6 Phosphate Dehydrogenase

1. Chicks, 3-d-old, of a heavy breed (HB) and a light breed (LB) were overfed for 18 d. The activities of acetyl-CoA carboxylase (EC 6.4.1.2; CBX), fatty acid synthetase (FAS), ATP citrate lyase (EC 4.1.3.8; CCE), NADP-malate dehydrogenase (decarboxylating) (EC 1.1.1.40; ME), 6-glucose-6-phosphate dehydrogenase (EC 1.1.1.49; G6PDH) and phosphogluconate dehydrogenase (EC 1.1.1.44; 6PGDH) were determined in abdominal adipose tissue (AT) and liver samples of overfed and ad lib.-fed chicks. Size and fat content of liver and adipose tissue were also determined in order to evaluate the extent of obesity.2. On ad lib.-feeding HB chicks consumed more food, gained more weight and deposited more fat than the corresponding LB chicks. Their lipogenic enzymes were more active than in the LB chicks in both adipose tissue and liver. The increase in food consumption (%) that could be achieved by overfeeding was three times greater in the LB chicks than in the HB chicks.3. Overfeeding increased the weight and fat content of liver and AT in both breeds. The specific activities of CBX, FAS, CCE and ME in liver and AT increased in the LB chicks only and the total activities of liver and AT enzymes increased much more in the LB chicks than in the HB chicks in which the increase was derived mainly from tissue enlargement.4. The activity of the pentose cycle dehydrogenases was very low in liver, but in AT about one third of the NADPH generating capacity could be accounted for by these dehydrogenases.5. The results show that lipogenic enzymes of chicks respond to an increased substrate flux. It is suggested that the enlarged liver, the higher participation of AT in lipogenesis and the uninterrupted supply of cropstored excess food enable the chick to accommodate the increased amounts of substrate with only moderate enzymic adaptation.

scholarly journals Analysis of lines of mice selected for fat content. 2. Correlated responses in the activities of enzymes involved in lipogenesis

1990 ◽  
Vol 55 (1) ◽  
pp. 55-61 ◽  
Author(s):  
Ian M. Hastings ◽  
William G. Hill
Keyword(s):  
De Novo ◽  
Fatty Acid Synthetase ◽  
Fat Content ◽  
Acetyl Coa Carboxylase ◽  
Correlated Responses ◽  
Atp Citrate Lyase ◽  
Citrate Lyase ◽  
Obesity In Mice ◽  
Made In

SummaryEstimates of the activities (Vmax) of six enzymes involved in de novo fat synthesis were made in replicated lines of mice differing in fat content. These lines had been selected high and low for 20 generations with three replicates each of Fat, Control and Lean lines and for a further eight generations high and low as an unreplicated line. The activities of ATP-citrate lyase (ACL), acetyl-CoA carboxylase (ACC), fatty acid synthetase (FAS), cytoplasmic malate dehydrogenase (MDH), malic enzyme (ME) and pyruvate kinase (PK) were determined in vitro in both liver and gonadal fatpad tissues taken at ages five and ten weeks. The activities of ACL, ACC, FAS and ME were significantly higher in the Fat than the Lean lines, and the differences were more pronounced at the earlier age and in the gonadal fatpad where activities in the Fat lines were higher by factors of 3·5, 2·4, 2·5 and 3·5 respectively. The activity of PK was unchanged in each tissue. MDH activity was significantly lower in adipose tissue in the Fat lines than the Lean lines at age ten weeks but not at age five weeks or in liver tissue. Results from replicates indicated that random genetic drift affected enzyme activities but nevertheless significant changes in activity were associated with the direction of selection. The changes in enzyme activity reported here are similar to those known to be associated with major mutations causing obesity in mice.

Adaptation to a high protein, carbohydrate-free diet induces a marked reduction of fatty acid synthesis and lipogenic enzymes in rat adipose tissue that is rapidly reverted by a balanced diet

2005 ◽  
Vol 83 (6) ◽  
pp. 477-482 ◽  
Author(s):  
S M.R.C Brito ◽  
M A.F Moura ◽  
N H Kawashita ◽  
W T.L Festuccia ◽  
M A.R Garófalo ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Pyruvate Dehydrogenase Complex ◽  
Acid Synthesis ◽  
High Protein ◽  
Acetyl Coa Carboxylase ◽  
Atp Citrate Lyase ◽  
Balanced Diet ◽  
Citrate Lyase ◽  
Glucose 6 Phosphate Dehydrogenase

We have previously shown that in vivo lipogenesis is markedly reduced in liver, carcass, and in 4 different depots of adipose tissue of rats adapted to a high protein, carbohydrate-free (HP) diet. In the present work, we investigate the activity of enzymes involved in lipogenesis in the epididymal adipose tissue (EPI) of rats adapted to an HP diet before and 12 h after a balanced diet was introduced. Rats fed an HP diet for 15 days showed a 60% reduction of EPI fatty acid synthesis in vivo that was accompanied by 45%–55% decreases in the activities of pyruvate dehydrogenase complex, ATP-citrate lyase, acetyl-CoA carboxylase, glucose-6-phosphate dehydrogenase, and malic enzyme. Reversion to a balanced diet for 12 h resulted in a normalization of in vivo EPI lipogenesis, and in a restoration of acetyl-CoA carboxylase activity to levels that did not differ significantly from control values. The activities of ATP-citrate lyase and pyruvate dehydrogenase complex increased to about 75%–86% of control values, but the activities of glucose-6-phosphate dehydrogenase and malic enzyme remained unchanged 12 h after diet reversion. The data indicate that in rats, the adjustment of adipose tissue lipogenic activity is an important component of the metabolic adaptation to different nutritional conditions. Key words: lipogenesis, lipogenic enzymes, high protein diet, diet reversion.

The effects of pregnancy, lactation and involution on the metabolism of glucose and acetate by rat liver tissue

1973 ◽  
Vol 40 (3) ◽  
pp. 339-351 ◽  
Author(s):  
R. W. Smith
Keyword(s):  
Fatty Acids ◽  
Rat Liver ◽  
Milk Fat ◽  
Late Pregnancy ◽  
Acetyl Coa Carboxylase ◽  
Atp Citrate Lyase ◽  
Phosphogluconate Dehydrogenase ◽  
Citrate Lyase ◽  
Pregnancy And Lactation ◽  
Glucose 6 Phosphate Dehydrogenase

SummaryThe incorporation of 14C from [1-14C] and [6-14C]glucose and [2-14C]acetate into CO2 and fatty acids by rat liver slices was measured at intervals during pregnancy, lactation and involution.During late pregnancy, the rates of oxidation of the C-1 and C-6 atoms of glucose were respectively 65 and 40 % higher than those for unmated animals. These increases were maintained during lactation, but the highest values were observed 3 days after weaning. Pregnancy and lactation had little effect on the oxidation of [2-14C]acetate.The incorporation of14C from all 3 labelled substrates into fatty acids was increased by a factor of 3–4 during late pregnancy. There were further increases during lactation, and 3 days after weaning the values were as much as 10 times as high as those for unmated animals.The incorporation of both [14C]glucose and [14C]acetate into cholesterol was increased by a factor of 6–7 during lactation.The activities of the enzymes glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, ATP citrate lyase and acetyl-CoA carboxylase were also increased during lactation and involution.The similarity between the changes summarized above and those brought about by changes in the pattern of food intake is discussed, and the idea that fatty acids synthesized from non-lipid precursors in the liver may make some contribution to the formation of milk fat is also considered.

scholarly journals Effects of PKB/Akt inhibitors on insulin-stimulated lipogenesis and phosphorylation state of lipogenic enzymes in white adipose tissue

2020 ◽  
Vol 477 (8) ◽  
pp. 1373-1389
Author(s):  
Nusrat Hussain ◽  
Sheng-Ju Chuang ◽  
Manuel Johanns ◽  
Didier Vertommen ◽  
Gregory R. Steinberg ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
White Adipose Tissue ◽  
Acute Effects ◽  
Lipogenic Enzymes ◽  
Atp Citrate Lyase ◽  
Phosphorylation State ◽  
Epididymal Fat ◽  
Citrate Lyase ◽  
Fat Pads

We investigated acute effects of two allosteric protein kinase B (PKB) inhibitors, MK-2206 and Akti-1/2, on insulin-stimulated lipogenesis in rat epididymal adipocytes incubated with fructose as carbohydrate substrate. In parallel, the phosphorylation state of lipogenic enzymes in adipocytes and incubated epididymal fat pads was monitored by immunoblotting. Preincubation of rat epididymal adipocytes with PKB inhibitors dose-dependently inhibited the following: insulin-stimulated lipogenesis, increased PKB Ser473 phosphorylation, increased PKB activity and decreased acetyl-CoA carboxylase (ACC) Ser79 phosphorylation. In contrast, the effect of insulin to decrease the phosphorylation of pyruvate dehydrogenase (PDH) at Ser293 and Ser300 was not abolished by PKB inhibition. Insulin treatment also induced ATP-citrate lyase (ACL) Ser454 phosphorylation, but this effect was less sensitive to PKB inhibitors than ACC dephosphorylation by insulin. In incubated rat epididymal fat pads, Akti-1/2 treatment reversed insulin-induced ACC dephosphorylation, while ACL phosphorylation by insulin was maintained. ACL and ACC purified from white adipose tissue were poor substrates for PKBα in vitro. However, effects of wortmannin and torin, along with Akti-1/2 and MK-2206, on recognized PKB target phosphorylation by insulin were similar to their effects on insulin-induced ACL phosphorylation, suggesting that PKB could be the physiological kinase for ACL phosphorylation by insulin. In incubated epididymal fat pads from wild-type versus ACC1/2 S79A/S212A knockin mice, effects of insulin to increase lipogenesis from radioactive fructose or from radioactive acetate were reduced but not abolished. Together, the results support a key role for PKB in mediating insulin-stimulated lipogenesis by decreasing ACC phosphorylation, but not by decreasing PDH phosphorylation.

scholarly journals Changes in activity of some enzymes involved in glucose utilization and formation in developing rat liver

1968 ◽  
Vol 106 (2) ◽  
pp. 321-329 ◽  
Author(s):  
R. G. Vernon ◽  
D G Walker
Keyword(s):  
Malate Dehydrogenase ◽  
Rat Liver ◽  
Postnatal Period ◽  
Supernatant Fraction ◽  
Atp Citrate Lyase ◽  
Carboxylase Activity ◽  
Phosphogluconate Dehydrogenase ◽  
Citrate Lyase ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Developing Rat

1. The activities of some enzymes involved in both the utilization of glucose (pyruvate kinase, ATP citrate lyase, NADP-specific malate dehydrogenase, glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and NADP-specific isocitrate dehydrogenase, all present in the supernatant fraction of liver homogenates) and the formation of glucose by gluconeogenesis (glucose 6-phosphatase in the whole homogenate and fructose 1,6-diphosphatase, phosphopyruvate carboxylase, NAD-specific malate dehydrogenase and fumarase in the supernatant fraction) have been determined in rat liver around birth and in the postnatal period until the end of weaning. 2. The activities of those enzymes involved in the conversion of glucose into lipid are low during the neonatal period and increase with weaning. NADP-specific malate dehydrogenase first appears and develops at the beginning of the weaning period. 3. The marked increase in cytoplasmic phosphopyruvate carboxylase activity at birth is probably the major factor initiating gluconeogenesis at that time. 4. The results are discussed against the known changes in dietary supplies and the known metabolic patterns during the period of development.

scholarly journals Variations in the activity of several enzymes in the mammary glands of non-pregnant, pregnant and lactating rabbits

1970 ◽  
Vol 116 (4) ◽  
pp. 657-661 ◽  
Author(s):  
P. E. Hartmann ◽  
E. A. Jones
Keyword(s):  
Mammary Gland ◽  
Small Mammals ◽  
Enzyme Activities ◽  
Mammary Glands ◽  
Acetyl Coa Carboxylase ◽  
Atp Citrate Lyase ◽  
Acetyl Coa ◽  
Phosphogluconate Dehydrogenase ◽  
Citrate Lyase ◽  
Lactation Cycle

1. The enzymes phosphofructokinase (EC 2.7.1.11), 6-phosphogluconate dehydrogenase (EC 1.1.1.44), phosphoglucomutase (EC 2.7.5.1), ATP–citrate lyase (EC 4.1.3.8), acetyl-CoA carboxylase (EC 6.4.1.2) and acetyl-CoA synthetase (EC 6.2.1.1) were assayed in rabbit mammary glands at various stages of the pregnancy–lactation cycle. 2. The activities of all enzymes were low during pregnancy and, with the exception of phosphofructokinase, in non-pregnant animals. Two- to ten-fold increases in enzyme activities occurred over the first 20 days of lactation. Although milk yield was considerably decreased, the enzyme activities remained elevated in late lactation (45 days after parturition). 3. These findings are discussed in relation to mammary-gland metabolism and compared with similar observations previously made on ruminants and other small mammals.

scholarly journals Dietary lipoic acid-dependent changes in the activity and mRNA levels of hepatic lipogenic enzymes in rats

2008 ◽  
Vol 100 (1) ◽  
pp. 79-87 ◽  
Author(s):  
Doan Thi Thanh Huong ◽  
Takashi Ide
Keyword(s):  
Lipoic Acid ◽  
Fatty Acid Synthase ◽  
Liver Lipid ◽  
Mrna Levels ◽  
Serum Concentrations ◽  
Lipogenic Enzymes ◽  
Atp Citrate Lyase ◽  
Citrate Lyase ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Lowered Serum

Effects of dietary α-lipoic acid on hepatic and serum lipid concentrations and the activity and mRNA levels of lipogenic enzymes were examined in rats. Rats were fed experimental diets containing varying amounts of lipoic acid (0, 1, 2·5, 5 g/kg) for 21 d. Lipoic acid profoundly decreased serum and liver concentrations of TAG, and also lowered serum concentrations of phospholipid and NEFA, and the concentration of cholesterol in the liver. A hypoglycaemic effect of this compound was also observed. Lipoic acid dose-dependently decreased the activity and mRNA levels of fatty acid synthase, ATP-citrate lyase, glucose 6-phosphate dehydrogenase, malic enzyme and pyruvate kinase in the liver despite that reductions were considerably attenuated in the NADPH-producing enzymes. This compound also dose-dependently lowered the mRNA levels of spot 14, adiponutrin, stearoyl-CoA desaturase 1, and Δ5- and Δ6-desaturases. In addition, lipoic acid dose-dependently lowered serum concentrations of insulin and leptin, but increased those of adiponectin. Lipoic acid appeared to reduce hepatic lipogenesis and hence decreases serum and liver lipid levels. Alterations in serum concentrations of insulin and (or) adiponectin may trigger this consequence.

scholarly journals Factors involved in changes in hepatic lipogenesis during development of the rat

1970 ◽  
Vol 118 (1) ◽  
pp. 155-162 ◽  
Author(s):  
Elizabeth A. Lockwood ◽  
E. Bailey ◽  
C. B. Taylor
Keyword(s):  
Enzyme Activities ◽  
Malic Enzyme ◽  
Hormonal Control ◽  
Male Rats ◽  
Acetyl Coa Carboxylase ◽  
Hepatic Enzymes ◽  
Atp Citrate Lyase ◽  
Acetyl Coa ◽  
Citrate Lyase ◽  
Glucose 6 Phosphate Dehydrogenase

1. Changes in the activities of acetyl-CoA carboxylase (EC 6.4.1.2), phosphofructokinase (EC 2.7.1.11), aldolase (EC 4.1.2.13), extramitochondrial aconitate hydratase (EC 4.2.1.3) and NADP-dependent isocitrate dehydrogenase (EC 1.1.1.42) have been measured in the livers of developing rats from late foetal life to maturity. 2. The effect of altering the weaning time on some enzymes associated with lipogenesis has been studied. Weaning rats at 15 days of age instead of 21 days results in an immediate increase in the activity of `malic' enzyme (EC 1.1.1.40) whereas the activities of glucose 6-phosphate dehydrogenase (EC 1.1.1.49) and ATP citrate lyase (EC 4.1.3.8) did not increase until 4–5 days and acetyl-CoA carboxylase 2–3 days after early weaning. Weaning rats on to an artificial-milk diet led to complete repression of the rise in activity of hepatic enzymes associated with lipogenesis normally found on weaning, except for `malic' enzyme, which increased in activity after 20 days of age. 3. The effect of intraperitoneal injections of glucagon, cortisol, growth hormone and thyroxine on the same hepatic enzymes has been investigated. Only thyroxine had any effect on enzyme activities and caused a 20-fold increase in `malic' enzyme activity and a twofold increase in ATP citrate lyase activity. 4. The activities of hepatic glucose 6-phosphate dehydrogenase and `malic' enzyme are higher in adult female than in adult male rats and it has been shown that this sex difference in enzyme activities is due to both male and female sex hormones. 5. Hepatic malate, citrate, pyruvate, glucose 6-phosphate and phosphoenolpyruvate concentrations have been measured throughout development. 6. The results are discussed in relation to the dietary and hormonal control of hepatic enzyme activities during development.

Rat-liver fatty-acid-synthesizing complex

1982 ◽  
Vol 2 (10) ◽  
pp. 841-848 ◽  
Author(s):  
P. M. Gillevet ◽  
K. Dakshinamurti
Keyword(s):  
Molecular Weight ◽  
Fatty Acid ◽  
High Molecular Weight ◽  
Fatty Acid Synthetase ◽  
Acetyl Coa Carboxylase ◽  
Atp Citrate Lyase ◽  
Acetyl Coa ◽  
High Molecular Weight Complex ◽  
Citrate Lyase

Under conditions favoring lipogenesis, a high-molecular-weight species of acetyl-CoA carboxylase was isolated that did not co-sediment with the in vitro polymerized enzyme. Assays for ATP-citrate lyase, acetyl-CoA carboxylase, and fatty acid synthetase indicated that all three enzymes were associated together as a high-molecular-weight complex and that under low-lipogenic conditions the level of these enzymes decreased. Phosphorylation of the isolated complex shifted it toward a lower molecular weight.

scholarly journals Initiation of lipogenic enzyme activities in rat mammary glands

1981 ◽  
Vol 198 (1) ◽  
pp. 187-192 ◽  
Author(s):  
P Martyn ◽  
I A Hansen
Keyword(s):  
Fatty Acid ◽  
Post Partum ◽  
Fatty Acid Synthetase ◽  
Mammary Glands ◽  
Synthetase Activity ◽  
Acetyl Coa Carboxylase ◽  
Atp Citrate Lyase ◽  
Acetyl Coa ◽  
Stimulate Activity ◽  
Citrate Lyase

The activities of acetyl-CoA carboxylase, ATP citrate-lyase and fatty acid synthetase remained low until parturition at 22 days of gestation and increased significantly within 1 day post partum. Administration of progesterone on days 20 and 21 and at parturition abolished the increases for at least 48 h after parturition. Removal of the pups of normal rats prevented the increases in activities of acetyl-CoA carboxylase and ATP citrate-lyase, but not of fatty acid synthetase, and administration of prolactin corticosterone or insulin did not stimulate activity. Tissue from suckled glands in which the ducts had been ligated at parturition showed no increase in the activities of acetyl-CoA carboxylase and ATP citrate-lyase within 24 h, whereas fatty acid synthetase activity was similar to that in the sham-operated contralateral glands. Foetoplacentectomy on day 18 increased the activity of fatty acid synthetase but not of acetyl-CoA carboxylase and ATP citrate-lyase; suckling of these dams by foster pups increased both acetyl-CoA carboxylase and ATP citrate-lyase.

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