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Batchuluun B, Pinkosky SL, Steinberg GR. Lipogenesis inhibitors: therapeutic opportunities and challenges. Nat Rev Drug Discov 2022; 21:283-305. [PMID: 35031766 PMCID: PMC8758994 DOI: 10.1038/s41573-021-00367-2] [Citation(s) in RCA: 128] [Impact Index Per Article: 64.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/03/2021] [Indexed: 12/12/2022]
Abstract
Fatty acids are essential for survival, acting as bioenergetic substrates, structural components and signalling molecules. Given their vital role, cells have evolved mechanisms to generate fatty acids from alternative carbon sources, through a process known as de novo lipogenesis (DNL). Despite the importance of DNL, aberrant upregulation is associated with a wide variety of pathologies. Inhibiting core enzymes of DNL, including citrate/isocitrate carrier (CIC), ATP-citrate lyase (ACLY), acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS), represents an attractive therapeutic strategy. Despite challenges related to efficacy, selectivity and safety, several new classes of synthetic DNL inhibitors have entered clinical-stage development and may become the foundation for a new class of therapeutics. De novo lipogenesis (DNL) is vital for the maintenance of whole-body and cellular homeostasis, but aberrant upregulation of the pathway is associated with a broad range of conditions, including cardiovascular disease, metabolic disorders and cancers. Here, Steinberg and colleagues provide an overview of the physiological and pathological roles of the core DNL enzymes and assess strategies and agents currently in development to therapeutically target them.
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Affiliation(s)
- Battsetseg Batchuluun
- Centre for Metabolism, Obesity and Diabetes Research, Department of Medicine and Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | | | - Gregory R Steinberg
- Centre for Metabolism, Obesity and Diabetes Research, Department of Medicine and Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada.
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Barry RM, Gitai Z. Self-assembling enzymes and the origins of the cytoskeleton. Curr Opin Microbiol 2011; 14:704-11. [PMID: 22014508 DOI: 10.1016/j.mib.2011.09.015] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 09/23/2011] [Accepted: 09/29/2011] [Indexed: 12/22/2022]
Abstract
The bacterial cytoskeleton is composed of a complex and diverse group of proteins that self-assemble into linear filaments. These filaments support and organize cellular architecture and provide a dynamic network controlling transport and localization within the cell. Here, we review recent discoveries related to a newly appreciated class of self-assembling proteins that expand our view of the bacterial cytoskeleton and provide potential explanations for its evolutionary origins. Specifically, several types of metabolic enzymes can form structures similar to established cytoskeletal filaments and, in some cases, these structures have been repurposed for structural uses independent of their normal roles. The behaviors of these enzymes suggest that some modern cytoskeletal proteins may have evolved from dual-role proteins with catalytic and structural functions.
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Affiliation(s)
- Rachael M Barry
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, United States
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Hardie DG, Carling D. The AMP-activated protein kinase--fuel gauge of the mammalian cell? EUROPEAN JOURNAL OF BIOCHEMISTRY 1997; 246:259-73. [PMID: 9208914 DOI: 10.1111/j.1432-1033.1997.00259.x] [Citation(s) in RCA: 1000] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A single entity, the AMP-activated protein kinase (AMPK), phosphorylates and regulates in vivo hydroxymethylglutaryl-CoA reductase and acetyl-CoA carboxylase (key regulatory enzymes of sterol synthesis and fatty acid synthesis, respectively), and probably many additional targets. The kinase is activated by high AMP and low ATP via a complex mechanism, which involves allosteric regulation, promotion of phosphorylation by an upstream protein kinase (AMPK kinase), and inhibition of dephosphorylation. This protein-kinase cascade represents a sensitive system, which is activated by cellular stresses that deplete ATP, and thus acts like a cellular fuel gauge. Our central hypothesis is that, when it detects a 'low-fuel' situation, it protects the cell by switching off ATP-consuming pathways (e.g. fatty acid synthesis and sterol synthesis) and switching on alternative pathways for ATP generation (e.g. fatty acid oxidation). Native AMP-activated protein kinase is a heterotrimer consisting of a catalytic alpha subunit, and beta and gamma subunits, which are also essential for activity. All three subunits have homologues in budding yeast, which are components of the SNF1 protein-kinase complex. SNF1 is activated by glucose starvation (which in yeast leads to ATP depletion) and genetic studies have shown that it is involved in derepression of glucose-repressed genes. This raises the intriguing possibility that AMPK may regulate gene expression in mammals. AMPK/SNF1 homologues are found in higher plants, and this protein-kinase cascade appears to be an ancient system which evolved to protect cells against the effects of nutritional or environmental stress.
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Affiliation(s)
- D G Hardie
- Biochemistry Department, The University, Dundee, UK.
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5
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Hopkins BA, Rakes AH, Daniel TE, Zimmerman CA, Croom WJ. Effects of intraperitoneal L-leucine, L-isoleucine, L-valine, and L-arginine on milk fat depression in early lactation cows. J Dairy Sci 1994; 77:1084-92. [PMID: 8201043 DOI: 10.3168/jds.s0022-0302(94)77043-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Eight Holstein cows were assigned following calving to two groups, balanced for parity, using a continuous completely randomized block design. Cows were fed a diet with 13.5% CP and 22.4% ADF from 35 to 55 DIM and then 13.8% CP and 15% ADF from 56 to 92 DIM. Alfalfa grass hay was the forage source, and concentrate mixtures contained primarily corn and soybean meal. Cows were given daily intraperitoneal infusions of a solution of L-Leu (46.1 g, 84.2 mM), L-Ile (31.4 g, 57.3 mM), L-Val (38.3 g, 78.2 mM), and L-Arg (25.0 g, 34.4 mM) or physiological saline following the a.m. milking from 42 through 84 DIM. Infusion of AA significantly increased plasma concentrations of Leu, Ile, Val, and Arg. Effects of AA infusion occurred during the low fiber period. Cows receiving AA maintained daily milk fat yield, increased p.m. milk fat yield, decreased less in p.m. milk fat percentage, and increased daily and p.m. yields of C16 fatty acids in milk. During the posttreatment period, cows previously receiving AA declined in daily milk fat yield, milk fat percentage, and total daily C4 to C16 milk fatty acid yield. Results suggest that the infused AA may have increased de novo synthesis of C16 milk fatty acids.
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Affiliation(s)
- B A Hopkins
- Department of Animal Science, North Carolina State University, Raleigh 27695-7621
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Williamson DH, Lund P. Cellular mechanisms for the regulation of adipose tissue lipid metabolism in pregnancy and lactation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1994; 352:45-70. [PMID: 7832059 DOI: 10.1007/978-1-4899-2575-6_4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- D H Williamson
- Metabolic Research Laboratory, Nuffield Department of Clinical Medicine, Radcliffe Infirmary, Oxford, United Kingdom
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Vasoactive Intestinal Peptide Stimulates Long-chain Fatty Acid Oxidation and Inhibits Acetyl-coenzyme A Carboxylase Activity in Isolated Rat Enterocytes. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)83676-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Clegg RA. Regulation of fatty acid uptake and synthesis in mammary and adipose tissues: contrasting roles for cyclic AMP. CURRENT TOPICS IN CELLULAR REGULATION 1988; 29:77-128. [PMID: 2840244 DOI: 10.1016/b978-0-12-152829-4.50005-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- R A Clegg
- Hannah Research Institute, Ayr, Scotland
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5 Acetyl-Coenzyme A Carboxylase. ACTA ACUST UNITED AC 1987. [DOI: 10.1016/s1874-6047(08)60256-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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De Spiegeleer B, Mannens G, Slegers G, Van den Bossche W, Claeys A. Direct assay for phosphotransacetylase and acetyl-coenzyme A carboxylase by high-performance liquid chromatography. Anal Biochem 1986; 158:195-200. [PMID: 2879484 DOI: 10.1016/0003-2697(86)90609-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A simple and specific assay to measure the activity of two coenzyme A derivative-processing enzymes, i.e., phosphotransacetylase (EC 2.3.1.8) and acetyl-coenzyme A carboxylase (EC 6.4.1.2), is described. The assay is based on the HPLC analysis of the short-chain coenzyme A derivatives formed by the enzymatic reaction, viz., acetyl-CoA and malonyl-CoA. For this purpose, ion-pair reversed-phase HPLC conditions are optimized. Furthermore, the influence of several variables on the enzyme reaction is studied in order to get maximum activity. Due to its short analysis time, good selectivity, and chromatogram information, HPLC proves to be an excellent method for the assay of these enzymes.
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Abstract
Recent advances in the understanding of glucagon-insulin relationships at the level of the islets of Langerhans and of hepatic fuel metabolism are reviewed and their impact on our understanding of glucagon physiology and pathophysiology is considered. It now appears that alpha cells can respond directly to hyperglycaemia in the absence of insulin and beta cells, but that antecedent hyperglycaemia masks or attenuates this response. Insulin appears to exert ongoing release inhibition upon glucagon secretion, probably via the intra-islet microvascular system that connects beta cells to alpha cells. Diabetic hyperglucagonemia in insulin deficient states appears to be secondary to lack of the restraining influence of insulin. The alpha cell response to glucopenia, by contrast, may be in large part mediated by release of noradrenaline from nerve endings in contact with alpha cells. Glucagon's action on glucose and ketone production by hepatocytes is mediated by increase in cyclic-AMP-dependent protein kinase. The opposing action of insulin upon glucagon-mediated events probably occurs largely at this level. Consequently, when glucagon secretion or action is blocked, cyclic-AMP-dependent protein kinase activity is low even in the absence of insulin, explaining why marked glucose and ketone production is absent in bihormonal deficiency states.
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Swenson TL, Porter JW. Mechanism of glucagon inhibition of liver acetyl-CoA carboxylase. Interrelationship of the effects of phosphorylation, polymer-protomer transition, and citrate on enzyme activity. J Biol Chem 1985. [DOI: 10.1016/s0021-9258(19)83693-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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13
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Ahmad PM, Gupta S, Barden RE, Ahmad F. Inhibitory effects of sulfhydryl reagents on acetyl-CoA carboxylase from rat mammary gland. BIOCHIMICA ET BIOPHYSICA ACTA 1984; 789:152-8. [PMID: 6148106 DOI: 10.1016/0167-4838(84)90199-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Rat mammary gland acetyl-CoA carboxylase (acetyl-CoA:carbon dioxide ligase (ADP forming), EC 6.4.1.2) is rapidly and irreversibly inactivated by micromolar concentrations of S-(4-bromo-2,3-dioxobutyl)-CoA (BDB-CoA) or p-hydroxymercuribenzoate (PHMB). Inhibition of both half reactions (i.e., the biotin carboxylation and the carboxyltransferase) catalyzed by acetyl-CoA carboxylase closely parallels loss in overall activity (malonyl-CoA synthesis). The presence of a substrate or product (acetyl-CoA, ATP, ADP, Pi) or inhibitor (palmitoyl-CoA) does not protect the enzyme from inhibition caused by BDB-CoA or PHMB. On the other hand, citrate, an activator of acetyl-CoA carboxylase, affords substantial protection against inhibition by BDB-CoA and PHMB. Covalent modification by BDB-CoA or PHMB appears to lock acetyl-CoA carboxylase in an inactive conformation (15-30 S) that is unable to undergo citrate-induced self-association into the catalytically competent polymeric form.
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Buechler KF, Gibson DM. Guanosine triphosphate and colchicine affect the activity and the polymeric state of acetyl-CoA carboxylase. Arch Biochem Biophys 1984; 233:698-707. [PMID: 6148916 DOI: 10.1016/0003-9861(84)90496-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Acetyl-CoA carboxylase was purified 300-fold from rat liver, in the absence of added citrate, by precipitation from an 18,000g supernatant in the presence of Triton X-100 at 105,000g and 20 degrees C, followed by chromatography on phosphocellulose. Acetyl-CoA carboxylase activity in this preparation was activated by preincubation with GTP (0.1-2.0 mM) and with citrate (20 mM). Colchicine (10(-6)-10(-3) M) inhibited enzyme activity and counteracted the effects of GTP and citrate. Sucrose density gradient centrifugation demonstrated that GTP and citrate preincubation promoted the formation of the polymeric, active enzyme, while colchicine engendered disassembly. Preincubation of the purified acetyl-CoA carboxylase at 4 degrees C caused inactivation and disassembly, which was countered by preincubation at 37 degrees C in the presence of GTP or citrate. These results suggest that GTP, like citrate, activates acetyl-CoA carboxylase by enhancing the conversion of the protomeric form of the enzyme to its more active, polymeric state.
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Chapter 1 Acetyl-coenzyme A carboxylase and its regulation. FATTV ACID METABOLISM AND ITS REGULATION 1984. [DOI: 10.1016/s0167-7306(08)60119-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Clarke SD. Rapid changes in chick liver acetyl-CoA carboxylase indicative of phosphorylation control. Biochem Biophys Res Commun 1983; 116:633-8. [PMID: 6140006 DOI: 10.1016/0006-291x(83)90571-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Liver fatty acid synthesis was suppressed 75,95 and 90% within 1, 2 and 4 hrs respectively of depriving chicks of food. Accompanying this rapid drop in lipogenesis was a marked reduction in acetyl-CoA carboxylase activity, i.e., 40 and 75% decrease after 2 and 4 hrs of fasting. Adding 10 mM citrate to the crude liver supernatant, or incubating the supernatant at 37 degrees, 30 min increased activity of the briefly fasted birds, but neither method restored carboxylase activity to fed level. Heat and citrate activation were additive and together resulted in an activity comparable to the fed condition. The heat-dependent activation was accelerated by exogenous phosphoprotein phosphatase, and completely blocked by 100 mM NaF. Thus, enhancement of carboxylase activity from liver of briefly fasted chicks appears to be a dephosphorylation process. This is the first report indicating acute changes in chick carboxylase activity may involve a phosphorylation-dephosphorylation mechanism.
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Lent BA, Kim KH. Phosphorylation and activation of acetyl-coenzyme A Carboxylase kinase by the catalytic subunit of cyclic AMP-dependent protein kinase. Arch Biochem Biophys 1983; 225:972-8. [PMID: 6312899 DOI: 10.1016/0003-9861(83)90113-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The catalytic subunit of cyclic AMP-dependent protein kinase stimulates the inactivation of acetyl-coenzyme A (CoA) carboxylase by acetyl-CoA carboxylase kinase. The stimulated inactivation of carboxylase is due to activation of carboxylase kinase by the catalytic subunit. Activation of carboxylase kinase activity is accompanied by the incorporation of 0.6 mol of phosphate per mole of carboxylase kinase. Addition of the regulatory subunit of cyclic AMP-dependent protein kinase prevents the activation of carboxylase kinase. Phosphorylation and activation of carboxylase kinase has no effect on the Km for ATP, but decreases the Km for acetyl-CoA carboxylase from 93 to 45 nM. Inactivation of carboxylase by the carboxylase kinase requires the presence of coenzyme A even when the activated carboxylase kinase is used. Acetyl-CoA carboxylase is not phosphorylated or inactivated by the catalytic subunit of cyclic AMP-dependent protein kinase.
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Monaco ME, Osborne CK, Bronzert TJ, Kidwell WR, Lippman ME. Characterization of insulin regulation of lipid synthesis in MCF-7 human breast cancer cells. Breast Cancer Res Treat 1983; 3:279-85. [PMID: 6367855 DOI: 10.1007/bf01806701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
Abstract
Stimulation of lipid synthesis by insulin in MCF-7 human breast cancer cells is characterized by an increase in acetate incorporation into long-chain fatty acids. The effects occurs in the absence of an increase in glucose uptake by the cells, and cannot be explained by a decrease in turnover of cellular fatty acids. Differential substrate experiments as well as direct measurement of enzyme activities indicate that insulin stimulates increases in activity of the first enzyme of the de novo pathway, acetyl CoA carboxylase. [32Pi] incorporation into phospholipids is also stimulated by insulin. Thin layer chromatography reveals five peaks of [32Pi]-labeled phospholipids corresponding in mobility to the following standards: lysophosphatidylcholine, sphingomyelin, phosphatidylcholine, phosphatidylinositol, and phosphatidylethanolamine. [32Pi] incorporation into each of these peaks is stimulated, although the degree of stimulation varies.
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Abstract
Phosphorylation and inactivation of acetyl-coenzyme A (CoA) carboxylase by acetyl-CoA carboxylase kinase in the presence of ATP and Mg2+ requires coenzyme A. Coenzyme A did not enhance the phosphorylation of alternative substrates of the carboxylase kinase such as protamine or histones. Analogs of coenzyme A were also effective in stimulating the inactivation of carboxylase. The KA of CoA for stimulated carboxylase inactivation was 25 microM. The presence of coenzyme A did not alter the Km of the carboxylase kinase for its substrates, ATP and acetyl-CoA carboxylase. Fluorescence binding studies showed that CoA binds to carboxylase but not to the kinase. The KD of CoA binding to carboxylase is 27 microM. These results indicate that coenzyme A, acting on acetyl-CoA carboxylase, may play an important role in the regulation of the covalent modification mechanism for acetyl-CoA carboxylase.
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Allred JB, Harris GJ, Goodson J. Regulation of purified rat liver acetyl CoA carboxylase by phosphorylation. J Lipid Res 1983. [DOI: 10.1016/s0022-2275(20)37985-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Lemmen C, Barth CA, Wolfram G, Zöllner N. Regulation of lipogenic enzymes in human diploid fibroblasts by hormones. BIOCHIMICA ET BIOPHYSICA ACTA 1983; 755:137-43. [PMID: 6130794 DOI: 10.1016/0304-4165(83)90283-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The hormonal regulation of two regulatory enzymes of fatty acid synthesis acetyl-CoA carboxylase (EC 6.4.1.2) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49), has been investigated in human diploid fibroblasts. There was a 35% increase in acetyl-CoA carboxylase activity, 72 h following addition of 10 microU/ml insulin to the culture medium. Addition of 1 microgram/ml of 3,3'5-triiodothyronine for 72 h resulted in an increase in acetyl-CoA carboxylase activity to 166% of the controls. The simultaneous addition of 1 microgram/ml triiodothyronine and 10 mU/ml insulin caused the enzyme activity to rise to 240% of the controls. A dose-dependent reduction in acetyl-CoA carboxylase activity was brought about by 1 X 10(-4) to 1 X 10(-3) M dibutyryl cyclic AMP. The earliest effect of dibutyryl cyclic AMP was observed within 24 h. Glucose-6-phosphate dehydrogenase followed qualitatively the same pattern of response, whereas the constitutive enzyme, lactate dehydrogenase (EC 1.1.1.27), did not show significant changes in these experiments. The data demonstrate common features of hormonal regulation of lipogenesis in human fibroblasts with liver and adipose tissue and substantiate the growing evidence that thyroid hormones are of major importance for the regulation of this process.
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Gillevet PM, Dakashinamurti K. Phosphorylation of proteolytically-nicked rat hepatic acetyl-CoA carboxylase. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1983; 15:1361-5. [PMID: 6139304 DOI: 10.1016/0020-711x(83)90027-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A partially-purified preparation of acetyl-CoA carboxylase was not inactivated by ATP and Mg2+ although it was phosphorylated. SDS gel electrophoresis of the phosphorylated enzyme showed phosphopeptides migrating at 140 and 40 K along with the 250 K native subunit. Phosphorylation by the catalytic subunit of cAMP-dependent protein kinase further phosphorylated an additional 120 K phosphopeptide. Neither cAMP-independent phosphorylation nor the cAMP-dependent phosphorylation of the enzyme resulted in a significant decrease in activity.
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Clarke BA, Clarke SD. Polymer-protomer transition of acetyl-CoA carboxylase as a regulator of lipogenesis in rat liver. Arch Biochem Biophys 1982; 218:92-100. [PMID: 6128959 DOI: 10.1016/0003-9861(82)90324-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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25
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Identification of the cyclic AMP and ATP binding sites of acetyl coenzyme A carboxylase by use of 5'-p-fluorosulfonylbenzoyladenosine. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(18)33969-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Tipper JP, Witters LA. In vitro phosphorylation and inactivation of rat liver acetyl-CoA carboxylase purified by avidin affinity chromatography. BIOCHIMICA ET BIOPHYSICA ACTA 1982; 715:162-9. [PMID: 6122472 DOI: 10.1016/0304-4165(82)90354-3] [Citation(s) in RCA: 71] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Acetyl-CoA carboxylase (EC 6.4.1.2) has been isolated from rat liver by an avidin-affinity chromatography technique. This preparation has a specific activity of 1.17 +/- 0.06 U/mg and appears as a major (240,000 dalton) and minor (140,000 dalton) band on SDS-polyacrylamide gel electrophoresis. Enzyme isolated by this technique can incorporate 1.09 +/- 0.07 mol phosphate per mol enzyme (Mr = 480,000) when incubated with the catalytic subunit of the cyclic AMP-dependent protein kinase at 30 degrees C for 1 h. The associated activity loss under these conditions is 57 +/- 4.0% when the enzyme is assayed in the presence of 2.0 mM citrate. Less inactivation is observed when the enzyme is assayed in the presence of 5.0 mM citrate. The specific protein inhibitor of the cyclic AMP-dependent protein kinase blocks both the protein kinase stimulated phosphorylation and inactivation of acetyl-CoA carboxylase. The phosphorylated, inactivated rat liver carboxylase can be partially dephosphorylated and reactivated by incubation with a partially purified protein phosphatase. Preparations of acetyl-CoA carboxylase also contained an endogenous protein kinase(s) which incorporated 0.26 +/- 0.11 mol phosphate per mol carboxylase (Mr = 480,000) accompanied by a 26 +/- 9% decline in activity. We have additionally confirmed that the rat mammary gland enzyme, also isolated by avidin affinity chromatography, can be both phosphorylated and inactivated upon incubation with the cyclic AMP-dependent kinase.
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Faulkner A, Peaker M. Reviews of the progress of dairy science: secretion of citrate into milk. J DAIRY RES 1982; 49:159-69. [PMID: 7042779 DOI: 10.1017/s002202990002224x] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Lent B, Kim K. Purification and properties of a kinase which phosphorylates and inactivates acetyl-CoA carboxylase. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(19)68122-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Ranganathan N, Linn T, Srere P. Phosphorylation of dephospho-ATP citrate lyase by the catalytic subunit of cAMP-dependent protein kinase. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(19)68251-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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31
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Beynen AC, Buechler KF, Van der Molen AJ, Geelen MJ. The effects of lactate and acetate on fatty acid and cholesterol biosynthesis by isolated rat hepatocytes. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1982; 14:165-9. [PMID: 6121723 DOI: 10.1016/0020-711x(82)90135-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
1. The present study demonstrates that lactate and acetate stimulate fatty acid synthesis and inhibit cholesterogenesis by isolated rat hepatocytes. 2. Exposure of the intact cells to lactate increases the activity of acetyl-CoA carboxylase, as can be measured in homogenates of these cells. A similar effect by acetate was not observed. 3. Both acetate and lactate drastically increase the cellular level of citrate. 4. Possible mechanisms underlying the difference in response of fatty acid and cholesterol synthesis to an increase in substrate availability are discussed. Futhermore, a mechanism is proposed for the lactate effect on acetyl-CoA carboxylase.
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Williamson JR, Cooper RH, Hoek JB. Role of calcium in the hormonal regulation of liver metabolism. BIOCHIMICA ET BIOPHYSICA ACTA 1981; 639:243-95. [PMID: 7039675 DOI: 10.1016/0304-4173(81)90012-4] [Citation(s) in RCA: 287] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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33
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Ly S, Kim K. Inactivation of hepatic acetyl-CoA carboxylase by catecholamine and its agonists through the alpha-adrenergic receptors. J Biol Chem 1981. [DOI: 10.1016/s0021-9258(19)68442-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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34
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Katz NR, Ick M. Induction of acetyl-CoA carboxylase in primary rat hepatocyte cultures by glucose and insulin. Biochem Biophys Res Commun 1981; 100:703-9. [PMID: 6115635 DOI: 10.1016/s0006-291x(81)80232-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Shiao MS, Drong RF, Porter JW. The purification and properties of a protein kinase and the partial purification of a phosphoprotein phosphatase that inactivate and activate acetyl-CoA carboxylase. Biochem Biophys Res Commun 1981; 98:80-7. [PMID: 6111317 DOI: 10.1016/0006-291x(81)91872-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Rieder H. NADP-dependent dehydrogenases in rat liver parenchyma. III. The description of a liponeogenic area on the basis of histochemically demonstrated enzyme activities and the neutral fat content during fasting and refeeding. HISTOCHEMISTRY 1981; 72:579-615. [PMID: 7298391 DOI: 10.1007/bf00493277] [Citation(s) in RCA: 39] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The activities of glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase(6PGDH), malic enzyme (ME) and isocitrate dehydrogenase (ICDh) were investigated with optimized histochemical methods (Rieder it al 1978), and the activity of 3-hydroxybutyrate dehydrogenase (3HBDH) and neutral fat content with conventional techniques in the liver of male rats under the following experimental dietary conditions: (A) Fasting for 0, 12 and 84h; (B) 84-h fasting followed by refeeding with a low-fat, high-carbohydrate diet for 6 h and for 2, 3, 5, 7, 11 and 14 nights; (C) refeeding with standard diet for 5 nights; (D) low-fat high-carbohydrate diet for 7 an 14 nights. The activities of G6PDH, 6PGDH and ME decreased slightly during fasting primarily in zone 1 and increased dramatically on refeeding with a low-fat, high-carbohydrate diet. This activity increase was confined mainly to zone 3 during the first 3 days and was accompanied by a deposition of neutral fats that began in zone 3 and progressed to zone 1. Neutral for accumulation was maximal after 3 nights, with a uniform accumulation of large droplets in all the hepatocytes; this was followed by a release that started in zone 3 and proceeded in a periportal direction. On the other hand, G6PDH, 6PGDH and ME attained their maximum activities after 5 amd 7 nights of low-fat diet, the activities being nearly homogeneously distributed over the liver acinus in a few cases. Subsequently the activities fill mainly in zone 1, causing the activity patterns and levels to approach those of the animals in group (D). In contrast to this, the activity of ICDH increased during fasting principally in zone 1, so that the otherwise steep activity gradient in favor of zone 3 lessened. Refeeding led at first to a fall of activity below the initial value, but later the normal distribution pattern was restored. The activity of 3HBDH showed a behavior similar to that of ICDH. The findings are discussed with reference to the functional heterogeneity of the liver parenchyma, and the existence of a liponeogenic area in zone 3 is proposed.
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Abdel-Halim MN, Yousufzai SY. Purification and properties of rat liver acetyl CoA carboxylase protein inhibitor. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1981; 13:1171-6. [PMID: 6119239 DOI: 10.1016/0020-711x(81)90210-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Ashcraft B, Fillers W, Augustine S, Clarke S. Polymer-protomer transition of acetyl-CoA carboxylase occurs in vivo and varies with nutritional conditions. J Biol Chem 1980. [DOI: 10.1016/s0021-9258(19)70420-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Hardie DG, Guy PS. Reversible phosphorylation and inactivation of acetyl-CoA carboxylase from lactating rat mammary gland by cyclic AMP-dependent protein kinase. EUROPEAN JOURNAL OF BIOCHEMISTRY 1980; 110:167-77. [PMID: 6108209 DOI: 10.1111/j.1432-1033.1980.tb04852.x] [Citation(s) in RCA: 104] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Acetyl-CoA carboxylase has been purified from lactating rat mammary gland using a combination of ammonium sulphate and poly(ethyleneglycol) precipitations. The enzyme was purified from 35--70-fold with a yield of over 50%, the exact figures being difficult to estimate because of activation of the enzyme that occurs during the preparation. The preparation was homogeneous by the criterion of polyacrylamide gel electrophoresis in sodium dodecyl sulphate and had a single subunit of molecular weight 240,000, containing 1.02 +/- 0.04 molecules of biotin and 3.1 +/- 1.7 molecules of alkali-labile phosphate per subunit. The purified enzyme was phosphorylated and inactivated rapidly when incubated in the presence of [gamma 32P]ATP and magnesium ions with the purified catalytic subunit of cyclic-AMP-dependent protein kinase from rabbit skeletal muscle. Both phosphorylation and inactivation are blocked by the heat-stable protein inhibitor of cyclic-AMP-dependent protein kinase, and can be reversed by incubation with purified protein phosphatase-1 from rabbit skeletal muscle. The inactivation by the protein kinase and reactivation by the protein phosphatase correlate with the near-stoichiometric phosphorylation and dephosphorylation of site(s) located in a single tryptic peptide. Phosphorylation does not affect the Km for substrates, but brings about a twofold decrease in V and a twofold increase in the apparent dissociation constant for the allosteric activator, citrate. We also present evidence that the activation of rabbit mammary acetyl-CoA carboxylase by protein phosphatase-1 described previously [Hardie and Cohen (1979) FEBS Lett. 103, 333-338] is due to dephosphorylation at site(s) which are not phosphorylated by either cyclic-AMP-dependent protein kinase or acetyl-CoA carboxylase kinase-2. These results suggest that the rapid inactivation of acetyl-CoA carboxylase, and hence fatty acid synthesis, by adrenaline in adipose tissue, or glucagon in the liver, is due to phosphorylation of the enzyme by cyclic-AMP-dependent protein kinase.
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Brzeski H, Linder S, Krondahl U, Ringertz NR. Pattern of polypeptide synthesis in myoblast hybrids. Exp Cell Res 1980; 128:267-78. [PMID: 7408992 DOI: 10.1016/0014-4827(80)90063-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Yeh L, Lee K, Kim K. Regulation of rat liver acetyl-CoA carboxylase. Regulation of phosphorylation and inactivation of acetyl-CoA carboxylase by the adenylate energy charge. J Biol Chem 1980. [DOI: 10.1016/s0021-9258(19)85891-x] [Citation(s) in RCA: 111] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Lee K, Kim K. Stimulation by epinephrine of in vivo phosphorylation and inactivation of acetyl coenzyme A carboxylase of rat epididymal adipose tissue. J Biol Chem 1979. [DOI: 10.1016/s0021-9258(17)37788-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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