Developmental and nutritional regulation of the messenger RNAs for fatty acid synthase, malic enzyme and albumin in the livers of embryonic and newly-hatched chicks

1. The rate of mammary-gland lipogenesis measured in vivo from 3H2O was suppressed after decreasing the milk demand by decreasing the number of pups from ten to two or three, as well as by giving diets containing lipid [Grigor & Warren (1980) Biochem. J. 188, 61-65]. 2. The specific activities of the lipogenic enzymes fatty acid synthase, glucose 6-phosphate dehydrogenase and ‘malic’ enzyme increased between 6- and 10-fold in the mammary gland and between 2- and 3-fold in the livers during the first 10 days of lactation. The increases in specific activity coupled with the doubling of liver mass which occurred during pregnancy and lactation resulted in considerable differences in total liver activities when compared with virgin animals. 3. Although consumption of a diet containing 20% peanut oil suppressed the activities of the three lipogenic enzymes in the livers, only the ‘malic’ enzyme was affected in the mammary glands. 4. In contrast, decreased milk demand did not affect the specific activities of any of the liver enzymes, whereas it resulted in suppression of all three lipogenic enzymes of the mammary glands. There was no effect on either the cytoplasmic malate dehydrogenase or the lactate dehydrogenase of the mammary gland. 5. In all the experiments performed, the activity of the fatty acid synthase correlated with the amount of material precipitated by the rabbit antibody raised against rat fatty acid synthase.

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Glucose stimulates transcription of fatty acid synthase and malic enzyme in avian hepatocytes

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1998.274.3.e493 ◽

1998 ◽

Vol 274 (3) ◽

pp. E493-E501 ◽

Cited By ~ 2

Author(s):

F. Bradley Hillgartner ◽

Tina Charron

Keyword(s):

Fatty Acid ◽

High Fat Diet ◽

Malic Enzyme ◽

Fatty Acid Synthase ◽

Primary Cultures ◽

Pentose Phosphate ◽

Mrna Abundance ◽

Low Fat Diet ◽

Low Carbohydrate

Transcription of fatty acid synthase (FAS) and malic enzyme (ME) in avian liver is low during starvation or feeding a low-carbohydrate, high-fat diet and high during feeding a high-carbohydrate, low-fat diet. The role of glucose in the nutritional control of FAS and ME was investigated by determining the effects of this metabolic fuel on expression of FAS and ME in primary cultures of chick embryo hepatocytes. In the presence of triiodothyronine, glucose (25 mM) stimulated an increase in the activity and mRNA abundance of FAS and ME. These effects required the phosphorylation of glucose to glucose 6-phosphate but not further metabolism downstream of the aldolase step of the glycolytic pathway. Xylitol mimicked the effects of glucose on FAS and ME expression, suggesting that an intermediate of the pentose phosphate pathway may be involved in mediating this response. The effects of glucose on the mRNA abundance of FAS and ME were accompanied by similar changes in transcription of FAS and ME. These data support the hypothesis that glucose plays a role in mediating the effects of nutritional manipulation on transcription of FAS and ME in liver.

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Association of fatty acid synthase gene and malic enzyme gene polymorphisms with fatness in turkeys

Poultry Science ◽

10.1093/ps/78.12.1651 ◽

1999 ◽

Vol 78 (12) ◽

pp. 1651-1657 ◽

Cited By ~ 12

Author(s):

M Sourdioux ◽

C Brevelet ◽

Y Delabrosse ◽

M Douaire

Keyword(s):

Fatty Acid ◽

Malic Enzyme ◽

Gene Polymorphisms ◽

Fatty Acid Synthase ◽

Enzyme Gene ◽

Malic Enzyme Gene ◽

Fatty Acid Synthase Gene

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Manganese influences the expression of fatty acid synthase and malic enzyme in cultured primary chicken hepatocytes

British Journal Of Nutrition ◽

10.1017/s0007114517002987 ◽

2017 ◽

Vol 118 (11) ◽

pp. 881-888 ◽

Cited By ~ 1

Author(s):

Lin Lu ◽

Meiling Wang ◽

Xiudong Liao ◽

Liyang Zhang ◽

Xugang Luo

Keyword(s):

Fatty Acid ◽

Mrna Expression ◽

Malic Enzyme ◽

Fatty Acid Synthase ◽

Cell Damage ◽

Manganese Chloride ◽

Transcriptional Level ◽

Mrna Levels ◽

Expression Levels ◽

Mrna Expression Levels

AbstractTwo experiments were designed to investigate the effects of Mn source and concentration on the mRNA expression and enzymatic activities of fatty acid synthase (FAS) and malic enzyme (ME) in cultured primary broiler hepatocytes. In Expt 1, primary broiler hepatocytes were treated with 0 (control), 0·25, 0·50 or 0·75 mmol/l of Mn as inorganic manganese chloride (MnCl2.4H2O) for 24 and 48 h. In Expt 2, primary broiler hepatocytes were incubated with 0 (control), 0·25 or 0·50 mmol/l of Mn as either manganese chloride or Mn–amino acid chelate for 48 h. The mRNA levels and activities of FAS and ME in the hepatocytes were measured in Expts 1 and 2. The results in Expt 1 showed that only at 48 h mRNA expression levels of FAS and ME in the hepatocytes decreased linearly (P<0·001) and quadratically (P<0·02) as supplemental Mn concentrations increased. In Expt 2, compared with the control, Mn supplementation reduced (P<0·01) the activities of FAS, mRNA expression levels of FAS and ME in the hepatocytes, and the efflux of lactic dehydrogenase to the medium. The supplemental Mn at 0·5 mmol/l showed a lower (P<0·03) ME mRNA expression level compared with the Mn group at 0·25 mmol/l. However, Mn source and the interaction between Mn source and concentration had no impacts (P>0·33) on any of the measured cellular parameters. The results suggested that Mn might reduce cell damage and regulate FAS and ME expression at a transcriptional level in primary cultured broiler hepatocytes.

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Occupancy and Function of the −150 Sterol Regulatory Element and −65 E-Box in Nutritional Regulation of the Fatty Acid Synthase Gene in Living Animals

Molecular and Cellular Biology ◽

10.1128/mcb.23.16.5896-5907.2003 ◽

2003 ◽

Vol 23 (16) ◽

pp. 5896-5907 ◽

Cited By ~ 78

Author(s):

Maria-Jesus Latasa ◽

Michael J. Griffin ◽

Yang Soo Moon ◽

Chulho Kang ◽

Hei Sook Sul

Keyword(s):

Fatty Acid ◽

Binding Sites ◽

Fatty Acid Synthase ◽

Regulatory Element ◽

Nutritional Regulation ◽

Fed State ◽

E Box ◽

Sterol Regulatory Element ◽

E Boxes

ABSTRACT Upstream regulatory factor (USF) and sterol regulatory element binding protein (SREBP) play key roles in the transcriptional regulation of the fatty acid synthase (FAS) gene by feeding and insulin. Due to the dual binding specificity of SREBP, as well as the presence of multiple consensus sites for these transcription factors in the FAS promoter, their physiologically relevant functional binding sites have been controversial. Here, in order to determine the occupancy of the putative USF and SREBP binding sites, we examined their protein-DNA interactions in living animals by using formaldehyde cross-linking and immunoprecipitation of chromatin and tested the function of these elements by employing mice transgenic for a reporter gene driven by various 5′ deletions as well as site-specific mutations of the FAS promoter. We show that the −332 and −65 E-boxes are bound by USF in both fasted and refed mice, while the −150 SRE is bound by SREBP-1 only in refed mice. We also found that mutation of either the −150 SRE or the −65 E-box abolishes the feeding-induced activation of the FAS promoter in transgenic mice. Furthermore, in vivo occupancy of the FAS promoter by SREBP in the fed state can be prevented by mutation not only of the −150 SRE but, unexpectedly, of the −65 E-box as well. We conclude that the FAS promoter is activated during refeeding via the induced binding of SREBP to the −150 SRE and that USF binding to the −65 E-box is also required for SREBP binding and activation of the FAS promoter.

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Messenger RNAs encoding lipoprotein lipase, fatty acid synthase and hormone-sensitive lipase in the adipose tissue of underfed-refed ewes and cows

Reproduction Nutrition Development ◽

10.1051/rnd:19980310 ◽

1998 ◽

Vol 38 (3) ◽

pp. 297-307 ◽

Cited By ~ 25

Author(s):

Muriel Bonnet ◽

Yannick Faulconnier ◽

Jeanne Fléchet ◽

Jean-François Hocquette ◽

Christine Leroux ◽

...

Keyword(s):

Adipose Tissue ◽

Fatty Acid ◽

Lipoprotein Lipase ◽

Fatty Acid Synthase ◽

Hormone Sensitive Lipase ◽

Messenger Rnas ◽

Hormone Sensitive

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Zinc, vanadate and selenate inhibit the tri-iodothyronine-induced expression of fatty acid synthase and malic enzyme in chick-embryo hepatocytes in culture

Biochemical Journal ◽

10.1042/bj3030213 ◽

1994 ◽

Vol 303 (1) ◽

pp. 213-216 ◽

Cited By ~ 13

Author(s):

Y Zhu ◽

A G Goodridge ◽

S R Stapleton

Keyword(s):

Fatty Acid ◽

Chick Embryo ◽

Malic Enzyme ◽

Fatty Acid Synthase ◽

Insulin Signalling ◽

Mrna Levels ◽

Maximal Inhibition ◽

Induced Expression ◽

Expression Of Genes ◽

Insulin Signalling Pathway

Insulin regulates the expression of genes involved in a variety of metabolic processes. In chick-embryo hepatocytes in culture, insulin amplifies the tri-iodothyronine (T3)-induced enzyme activity, and the level and rate of transcription of mRNA for both fatty acid synthase (FAS) and malic enzyme (ME). Insulin alone, however, has little or no effect on the expression of these genes. In chick-embryo hepatocytes, the mechanism by which insulin regulates the expression of these or other genes is not known. Several recent studies have compared the effects of zinc, vanadate and selenate on insulin-sensitive processes in an attempt to probe the mechanism of insulin action. Because zinc, vanadate and selenate mimic the effects of insulin on several processes, they have been termed insulin-mimetics. We have studied the effect of zinc, vanadate and selenate on the T3-induced expression of both FAS and ME. Like insulin, these agents had little or no effect on the basal activities for FAS and ME in chick-embryo hepatocytes in culture for 48 h. Unlike insulin, however, zinc, vanadate and selenate inhibited the T3-induced activities and mRNA levels of both FAS and ME. Maximal inhibition was achieved at concentrations of 50 microM zinc or vanadate, or 20 microM selenate. Zinc and vanadate also inhibited the T3-induced transcription of the FAS and ME genes. Although the mechanism of this inhibition is unknown, our results indicate that it is not mediated through inhibition of binding of T3 to its nuclear receptor nor through a general toxic effect. Thus zinc, vanadate and selenate are not insulin-mimetics under all conditions, and their effects on other insulin-sensitive processes may be fortuitous and unrelated to actions or components of the insulin signalling pathway.

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Hormonal regulation of rat foetal lipogenesis in brown-adipocyte primary cultures

Biochemical Journal ◽

10.1042/bj2510617 ◽

1988 ◽

Vol 251 (2) ◽

pp. 617-620 ◽

Cited By ~ 20

Author(s):

M Lorenzo ◽

C Roncero ◽

I Fabregat ◽

M Benito

Keyword(s):

Fatty Acid ◽

Malic Enzyme ◽

Hormonal Regulation ◽

Fatty Acid Synthase ◽

Primary Cultures ◽

Brown Adipocyte ◽

Acetyl Coa Carboxylase ◽

Acetyl Coa ◽

Short Times ◽

Stimulation Of

Insulin stimulates lipogenesis by 100% for 5 h by a covalent modulation of acetyl-CoA carboxylase, and by 200% for 24 h by increasing malic enzyme and fatty acid synthase enzymic activities in brown-adipocyte primary cultures. At short times, noradrenaline and isoprenaline decrease lipogenesis. However, phenylephrine and glucagon have no effect. At long times, dexamethasone inhibits lipogenesis. This effect is precluded in the presence of insulin. Progesterone and tri-iodothyronine, alone or in the presence of insulin, produce a stimulation of the rates of lipogenesis.

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