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Fushimi T, Izumi Y, Takahashi M, Hata K, Murano Y, Bamba T. Dynamic Metabolome Analysis Reveals the Metabolic Fate of Medium-Chain Fatty Acids in AML12 Cells. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:11997-12010. [PMID: 33073987 DOI: 10.1021/acs.jafc.0c04723] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Several studies in hepatocyte cell lines reported that medium-chain fatty acids (MCFAs) with 6-12 carbons showed different metabolic properties from long-chain fatty acids (LCFAs). However, these studies reported unclear effects of different fatty acid molecules on hepatocyte metabolism. This study is aimed to capture the metabolic kinetics of MCFA assimilation in AML12 cells treated with octanoic acid (FA 8:0), decanoic acid (FA 10:0), or lauric acid (FA12:0) [LCFA; oleic acid (FA 18:1)] via metabolic profiling and dynamic metabolome analysis with 13C-labeling. The concentrations of total ketone bodies in the media of cells treated with FA 8:0 or FA 10:0 were 3.22- or 3.69-fold higher than those obtained with FA 18:1 treatment, respectively. FA 12:0 treatment did not significantly increase ketone body levels compared to DMSO treatment (control), whereas FA 12:0 treatment increased intracellular triacylglycerol (TG) levels 15.4 times compared to the control. Metabolic profiles of FA 12:0-treated samples differed from those of the FA 8:0-treated and FA 10:0-treated samples, suggesting that metabolic assimilation of MCFAs differed significantly depending on the MCFA type. Furthermore, the dynamic metabolome analysis clearly revealed that FA 8:0 was rapidly and quantitatively oxidized to acetyl-CoA and assimilated into ketone bodies, citrate cycle intermediates, and glucogenic amino acids but not readily into TGs.
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Affiliation(s)
- Tatsuya Fushimi
- Central Research Laboratory, The Nisshin OilliO Group, Ltd., 1 Shinmori-cho, Isogo-ku, Yokohama 235-8558, Japan
- Department of Systems Life Sciences, Graduate School of Systems Life Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Yoshihiro Izumi
- Department of Systems Life Sciences, Graduate School of Systems Life Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
- Division of Metabolomics, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Masatomo Takahashi
- Division of Metabolomics, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Kosuke Hata
- Division of Metabolomics, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Yoshihiro Murano
- Central Research Laboratory, The Nisshin OilliO Group, Ltd., 1 Shinmori-cho, Isogo-ku, Yokohama 235-8558, Japan
| | - Takeshi Bamba
- Department of Systems Life Sciences, Graduate School of Systems Life Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
- Division of Metabolomics, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
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Yang Y, Yan B, Cheng X, Ding Y, Tian X, Shi Y, Le G. Metabolomic studies on the systemic responses of mice with oxidative stress induced by short-term oxidized tyrosine administration. RSC Adv 2017. [DOI: 10.1039/c7ra02665j] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Oxidized tyrosine (O-Tyr) has attracted more interest in recent years because many researchers have discovered that it and its product (dityrosine) are associated with pathological conditions, especially various age-related disorders in biological systems.
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Affiliation(s)
- Yuhui Yang
- The Laboratory of Food Nutrition and Functional Factors
- School of Food Science and Technology
- Jiangnan University
- Wuxi 214122
- China
| | - Biao Yan
- The Laboratory of Food Nutrition and Functional Factors
- School of Food Science and Technology
- Jiangnan University
- Wuxi 214122
- China
| | - Xiangrong Cheng
- The Laboratory of Food Nutrition and Functional Factors
- School of Food Science and Technology
- Jiangnan University
- Wuxi 214122
- China
| | - Yinyi Ding
- The Laboratory of Food Nutrition and Functional Factors
- School of Food Science and Technology
- Jiangnan University
- Wuxi 214122
- China
| | - Xu Tian
- The Laboratory of Food Nutrition and Functional Factors
- School of Food Science and Technology
- Jiangnan University
- Wuxi 214122
- China
| | - Yonghui Shi
- The Laboratory of Food Nutrition and Functional Factors
- School of Food Science and Technology
- Jiangnan University
- Wuxi 214122
- China
| | - Guowei Le
- The Laboratory of Food Nutrition and Functional Factors
- School of Food Science and Technology
- Jiangnan University
- Wuxi 214122
- China
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Genetic deletion of Rheb1 in the brain reduces food intake and causes hypoglycemia with altered peripheral metabolism. Int J Mol Sci 2014; 15:1499-510. [PMID: 24451134 PMCID: PMC3907882 DOI: 10.3390/ijms15011499] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Revised: 12/12/2013] [Accepted: 01/07/2014] [Indexed: 02/05/2023] Open
Abstract
Excessive food/energy intake is linked to obesity and metabolic disorders, such as diabetes. The hypothalamus in the brain plays a critical role in the control of food intake and peripheral metabolism. The signaling pathways in hypothalamic neurons that regulate food intake and peripheral metabolism need to be better understood for developing pharmacological interventions to manage eating behavior and obesity. Mammalian target of rapamycin (mTOR), a serine/threonine kinase, is a master regulator of cellular metabolism in different cell types. Pharmacological manipulations of mTOR complex 1 (mTORC1) activity in hypothalamic neurons alter food intake and body weight. Our previous study identified Rheb1 (Ras homolog enriched in brain 1) as an essential activator of mTORC1 activity in the brain. Here we examine whether central Rheb1 regulates food intake and peripheral metabolism through mTORC1 signaling. We find that genetic deletion of Rheb1 in the brain causes a reduction in mTORC1 activity and impairs normal food intake. As a result, Rheb1 knockout mice exhibit hypoglycemia and increased lipid mobilization in adipose tissue and ketogenesis in the liver. Our work highlights the importance of central Rheb1 signaling in euglycemia and energy homeostasis in animals.
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Watmough NJ, Turnbull DM, Sherratt HS, Bartlett K. Measurement of the acyl-CoA intermediates of beta-oxidation by h.p.l.c. with on-line radiochemical and photodiode-array detection. Application to the study of [U-14C]hexadecanoate oxidation by intact rat liver mitochondria. Biochem J 1989; 262:261-9. [PMID: 2818568 PMCID: PMC1133256 DOI: 10.1042/bj2620261] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The quantitative isolation of acyl-CoA esters of chain length C2-C17 from mitochondrial incubations and their analysis by reverse-phase radio-h.p.l.c. is described. Photodiode-array detection was used to characterize 2-enoyl-CoA esters. The chromatographic behaviour of all 27 intermediates of the beta-oxidation of hexadecanoyl-CoA is documented. Only C16, C14 and C12 intermediates were detected in uncoupled mitochondria oxidizing [U-14C]hexadecanoyl-CoA in the presence of fluorocitrate and carnitine, providing evidence for some organization of the enzymes of beta-oxidation [Garland, Shepherd & Yates (1965) Biochem. J. 97, 587-594; Sumegi & Srere (1984) J. Biol. Chem. 259, 8748-8752]. Rotenone increased concentrations of 3-hydroxyacyl-CoA and 2-enoyl-CoA esters and inhibited flux. These experiments provide the first direct unambiguous measurements of acyl-CoA esters in intact respiring rat liver mitochondrial fractions.
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Affiliation(s)
- N J Watmough
- Department of Neurology, University of Newcastle upon Tyne, U.K
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Lysiak W, Lilly K, DiLisa F, Toth PP, Bieber LL. Quantitation of the effect of L-carnitine on the levels of acid-soluble short-chain acyl-CoA and CoASH in rat heart and liver mitochondria. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(19)57279-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Balzer I, Huth W. Mitochondrial acetyl-CoA acetyltransferase in liver and extrahepatic tissues: role of modification by coenzyme A. BIOCHIMICA ET BIOPHYSICA ACTA 1986; 870:350-6. [PMID: 2869784 DOI: 10.1016/0167-4838(86)90239-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The influence of clofibrate and di(2-ethylhexyl)phthalate on mitochondrial acetyl-CoA acetyltransferase (acetyl-CoA: acetyl-CoA C-acetyltransferase, EC 2.3.1.9), the rate-limiting ketogenic enzyme, which can be modified and inactivated by CoA, was investigated. In fed rats, both compounds induced a doubling of ketone bodies in the blood and, moreover, an increase by about 13% in the hepatic relative amount of the unmodified, i.e., the most active form of the enzyme (immunoreactive protein). This shift would account for an elevation of overall enzyme activity by about 5% only. Thus, the CoA modification of mitochondrial acetyl-CoA acetyltransferase did not explain the entire augmentation of ketone bodies. However, clofibrate and di(2-ethylhexyl)phthalate also increased the immunospecific protein and enzyme activity by approx. 2- and 3-fold, respectively. These effects were observed in liver, but not in several extrahepatic tissues.
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Bremer J, Osmundsen H. Chapter 5 Fatty acid oxidation and its regulation. ACTA ACUST UNITED AC 1984. [DOI: 10.1016/s0167-7306(08)60123-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
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Zammit VA. Mechanisms of regulation of the partition of fatty acids between oxidation and esterification in the liver. Prog Lipid Res 1984; 23:39-67. [PMID: 6152703 DOI: 10.1016/0163-7827(84)90005-5] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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de Bruijne JJ, Lopes-Cardozo M. Ketogenesis in mitochondria isolated from liver biopsies of normal and starved dogs: comparison with rat-liver mitochondria. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1983; 75:557-62. [PMID: 6617155 DOI: 10.1016/0305-0491(83)90095-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Fatty acid oxidation and ketogenesis were studied in isolated dog-liver mitochondria in order to investigate whether the absence of hyperketonemia in fasting dogs results from a low capacity of hepatic ketogenesis. Isolated rat-liver mitochondria were used as reference. The results indicate that: (a) Dog-liver mitochondria oxidize long-chain fatty acids and produce ketone bodies at about equal rates as rat-liver mitochondria. No differences were detected in the regulation of ketogenesis. (b) Rates of oxidation of medium-chain fatty acids are significantly lower in dog-liver mitochondria than in rat-liver mitochondria. (c) Fasting does not influence the capacity of liver mitochondria for fatty acid oxidation but their ketogenic capacity is slightly enhanced in both species. The regulation of the energy metabolism in the fasting dog is discussed and compared with that in other mammalian species.
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Demaugre F, Buc H, Girard J, Leroux JP. Role of the mitochondrial metabolism of pyruvate on the regulation of ketogenesis in rat hepatocytes. Metabolism 1983; 32:40-8. [PMID: 6848896 DOI: 10.1016/0026-0495(83)90153-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In hepatocytes isolated from fed rats the inhibition of lipogenesis (-80%) by 5-tetradecyloxy-2-furoate (an inhibitor of acetylCoA carboxylase) and alpha-cyano-3-hydroxycinnamate (an inhibitor of pyruvate entry into mitochondria) increases the oxidation of 0.35 mM oleate respectively by 70% and 90%. 5-tetradecyloxy-2-furoate increases ketone body production from oleate only by 30% and has no effect on ketogenesis from octanoate, whereas alpha-cyano-3-hydroxycinnamate mimics the effects of fasting on ketone body production: It increases ketogenesis from 0.35 mM oleate by 90%, from 0.78 mM oleate by 25% and from 1.57 mM butyrate by 37%. alpha-cyano-3-hydroxycinnamate also decreases the activity of tricarboxylic acid cycle and the production of malate and citrate. In hepatocytes from fasted rats, alpha-cyano-3-hydroxycinnamate does not modify ketogenesis from oleate, unless cells are incubated with a mixture of lactate and pyruvate. A lactate and pyruvate mixture decreases ketogenesis from oleate and octanoate and increases citrate and malate production without modifying the uptake of fatty acids. This effect is potentiated by 3-mercaptopicolinate, an inhibitor of phosphoenolpyruvate carboxykinase. The results cannot be interpreted only by the effects of malonylCoA on carnitine acyltransferase. They are discussed with respect to the possible involvement of mitochondrial oxaloacetate concentration in the regulation of ketogenesis.
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Davis-van Thienen W, Davis E. The effects of energetic steady state, pyruvate concentration, and octanoyl-(–)-carnitine on the relative rates of carboxylation and decarboxylation of pyruvate by rat liver mitochondria. J Biol Chem 1981. [DOI: 10.1016/s0021-9258(19)68853-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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Yeh YY, Zee P. Fatty acid oxidation in isolated rat liver mitochondria. Developmental changes and their relation to hepatic levels of carnitine and glycogen and to carnitine acyltransferase activity. Arch Biochem Biophys 1979; 197:560-9. [PMID: 507829 DOI: 10.1016/0003-9861(79)90280-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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[14C]palmitate uptake in isolated rat liver mitochondria: effects of fasting, diabetes mellitus, and inhibitors of carnitine acyltransferase. J Lipid Res 1978. [DOI: 10.1016/s0022-2275(20)41268-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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16
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Demaugre F, Leroux JP, Cartier P. The effects of pyruvate concentration, dichloroacetate and alpha-cyano-4-hydroxycinnamate on gluconeogenesis, ketogenesis and [3-hydroxybutyrate]/[3-oxobutyrate] ratios in isolated rat hepatocytes. Biochem J 1978; 172:91-6. [PMID: 656077 PMCID: PMC1185666 DOI: 10.1042/bj1720091] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
1. In isolated rat hepatocytes incubated with pyruvate, ketogenesis increased with increasing pyruvate concentrations and decreased under the influence of 1 mM-alpha-cyano-4-hydroxycinnamate, a known inhibitor of pyruvate transport. Ketogenesis from pyruvate was higher by 30% in hepatocytes prepared from starved than from fed rats. 2. With pyruvate as substrate, 2 mM-dichloroacetate had no effect on ketogenesis of starved-rat hepatocytes, but increased ketogenesis of fed-rat hepatocytes to the 'starved' value. Gluconeogenesis from pyruvate, lactate and alanine, but not from glycerol, was inhibited by dichloroacetate. Both increased ketogenesis and decreased gluconeogenesis may result from an inhibition of pyruvate carboxylase by dichloroacetate. 3. Mitochondria were rapidly isolated from incubated hepatocytes, and [3-hydroxybutyrate]/[3-oxobutyrate] ratios were measured in the mitochondrial pellet ('mitochondrial' ratios) and in whole-cell suspensions ('total' ratios). Increasing pyruvate concentrations increased mitochondrial and decreased total ratios. In the presence of pyruvate (2 to 10 mM), dichloroacetate decreased mitochondrial and increased total ratios.
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Dennis S, DeBuysere M, Scholz R, Olson M. Studies on the relationship between ketogenesis and pyruvate oxidation in isolated rat liver mitochondria. J Biol Chem 1978. [DOI: 10.1016/s0021-9258(17)38063-8] [Citation(s) in RCA: 32] [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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Lopes-Cardozo M, Klazinga W, van den Bergh SG. Evidence for a homogeneous pool of acetyl-CoA in rat-liver mitochondria. EUROPEAN JOURNAL OF BIOCHEMISTRY 1978; 83:635-40. [PMID: 631140 DOI: 10.1111/j.1432-1033.1978.tb12133.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Rat-liver mitochondria oxidized [1-14C]palmitate or [U-14C]palmitate and unlabelled pyruvate in a medium containing fluorocitrate and L-carnitine. The oxidation products (acetyl-L-carnitine, ketone bodies and citrate) were separated by anion-exchange chromatography and their specific activities were determined. The distribution of radioactivity over the two halves of the ketone bodies was essayed. Significant differences between the specific activities of citrate, acetyl-L-carnitine and the carboxylhalf of the ketone bodies were not observed; this was consistently the case, even when pyruvate contributed for more than 80% to the acetyl-CoA pool. Our results argue against compartition of mitochondrial acetyl-CoA. Instead, they strongly suggest that the acetyl-CoA originating from the simultaneous oxidation of pyruvate and palmitate equilibrates before being distributed over the various pathways of further metabolism.
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Saudubray JM, Marsac C, Cathelineau CL, Besson Leaud M, Leroux JP. Neonatal congenital lactic acidosis with pyruvate carboxylase deficiency in two siblings. ACTA PAEDIATRICA SCANDINAVICA 1976; 65:717-24. [PMID: 826106 DOI: 10.1111/j.1651-2227.1976.tb18009.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The authors report 2 familial cases of neonatal congenital lactic acidosis with pyruvate carboxylase deficiency in the liver. In both cases, disorders started immediately after birth and were characterized by major neurological symptoms, acute metabolic acidosis with hyperketonemia and hyperammonemia. Course was rapidly fatal despite intensive care, bicarbonate therapy and several therapeutic attempts with biotin and thiamine. Hyperlactacidemia was associated with dramatic increase in lactate/pyruvate ratio, without anoxia, in contrast with decreased beta hydroxybutyrate/acetoacetate ratio. This unusual metabolic pattern may be assumed to result from decreased oxaloacetate synthesis as a result of pyruvate carboxylase deficiency, and impairment of oxaloacetate dependent mitochondrial redox shuttles. Post mortem enzymatic study of the liver and kidney showed biotin unresponsive total deficiency of pyruvate carboxylase. Other gluconeogenic enzyme activities were normal.
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Stanley H, Sherratt A, Osmundsen H. On the mechanisms of some pharmacological actions of the hypoglycaemic toxins hypoglycin and pent-4-enoic acid. A way out of the present confusion. Biochem Pharmacol 1976; 25:743-50. [PMID: 938577 DOI: 10.1016/0006-2952(76)90139-8] [Citation(s) in RCA: 81] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Lopes-Cardozo M, Mulder I, van Vugt F, Hermans PG, van den Bergh SG, Klazinga W, de Vries-Akkerman E. Aspects of ketogenesis: control and mechanism of ketone-body formation in isolated rat-liver mitochondria. Mol Cell Biochem 1975; 9:155-73. [PMID: 1196305 DOI: 10.1007/bf01751311] [Citation(s) in RCA: 43] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The synthesis of ketone bodies by intact isolated rat-liver mitochondria has been studied at varying rates of acetyl-CoA production and of acetyl-CoA utilization in the Krebs cycle. Factors which enhanced the rate of acetyl-CoA production caused an increase in the fraction of acetyl-CoA which was incorporated into ketone bodies. On the other hand, it was found that factors which stimulated the formation of citrate lowered the relative rate of ketogenesis. It is concluded that acetyl-CoA is preferentially used for citrate synthesis, if the level of oxaloacetate in the mitochondrial matrix space is adequate. The intramitochondrial level of oxaloacetate, which is determined by the malate concentration and the ratio of NADH over NAD+, is the main factor controlling the rate of citrate synthesis. The ATP/ADP ratio per se does not affect the activity of citrate synthase in this in vitro system. Ketogenesis can be described as an overflow of acetyl-groups: Ketone-body formation is stimulated only when the rate of acetyl-CoA production increases beyond the capacity for citrate synthesis. The interaction between fatty acid oxidation and pyruvate metabolism and the effects of long-chain acyl-CoA on mitochondrial metabolism are discussed. Ketone bodies which were generated during the oxidation of [1-14C] fatty acids were preferentially labelled in their carboxyl group. This carboxyl group had the same specific activity as the acetyl-CoA pool, whereas the specific activity of the acetone moiety of acetoacetate was much lower, especially at low rates of ketone-body formation. The activities of acetoacetyl-CoA deacylase and the hydroxymethylglutaryl-CoA (HMG-CoA) pathway were compared in soluble and mitochondrial fractions of rat- and cow-liver in different ketotic states. In rat-liver mitochondria, both pathways of acetoacetate synthesis were stimulated upon starvation or in alloxan diabetes. In cow liver, only the HMG-CoA pathway was increased during ketosis in the mitochondrial as well as in the soluble fraction.
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Amatruda JM, Margolis S, Lockwood DH. Regulation of ketone body production from (14C)palmitate in rat liver mitochondria: effects of cyclic nucleotides and unlabeled fatty acids. Biochem Biophys Res Commun 1975; 67:1337-45. [PMID: 173341 DOI: 10.1016/0006-291x(75)90174-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Lopes-Cardozo M, van den Bergh SG. Ketogenesis in isolated rat-liver mitochondria. IV. Oxaloacetate decarboxylation: consequences for metabolic calculations. BIOCHIMICA ET BIOPHYSICA ACTA 1974; 357:193-203. [PMID: 4420547 DOI: 10.1016/0005-2728(74)90060-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Lopes-Cardozo M, van den Bergh SG. Ketogenesis in isolated rat liver mitochondria. II. Factors affecting the rate of beta-oxidation. BIOCHIMICA ET BIOPHYSICA ACTA 1974; 357:43-52. [PMID: 4414031 DOI: 10.1016/0005-2728(74)90110-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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