Physiological Role of Peroxisomal β-Oxidation in Liver of Fasted Rats

Ishii, Hidemi; Horie, Seichi; Suga, Tetsuya

doi:10.1093/oxfordjournals.jbchem.a132931

Cited by 94 publications

(26 citation statements)

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“…Starvation has been reported to induce the peroxisomal /?-oxidation [30], but the induction of both the peroxisomal /?-oxidation system and the hydrolase activity was not marked in the present study.…”

Section: Effects Qf Peroxisome Pvoliyeratorscontrasting

confidence: 87%

Induction of a Novel Long‐Chain Acyl‐CoA Hydrolase in Rat Liver by Administration of Peroxisome Proliferators

Miyazawa

Furuta

Hashimoto

1981

European Journal of Biochemistry

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The activity of long-chain acyl-CoA hydrolase in rat liver was increased by the administration of peroxisome proliferators, such as ethyl p-chlorophenoxyisobutyrate, di(2-ethy1hexyl)phthalate or acetylsalicylic acid. The induced activity was mainly confined 'in the soluble fluid after the subcellular fractionation. The enzyme was purified nearly to homogeneity from livers of rats treated with di(2-ethy1hexyl)phthalate. The specific activity of the final preparation was 247 pmol palmitoyl-CoA hydrolyzed min-' mg protein-'. The molecular weight of the native enzyme was estimated to be 150000 by gel filtration and that of the subunits was 41 000 by sodium dodecyl sulfate/polyacrylamide gel electrophoresis. The activity of the enzyme was not increased but inhibited by bovine serum albumin or Triton X-100. The molecular. and catalytic properties of the enzyme suggest that the induced enzyme was different from mitochondria1 and microsomal long-chain acyl-CoA hydrolases in liver.Long-chain fatty acyl-CoA hydrolases are present in various mammalian tissues [I -81. In rat liver, the enzymes are mainly localized in mitochondria and microsomes [2,3]. These enzymes in both particulates have been purified and characterized [4,5]. During the course of our study on the effect of di(2-ethylhexyl)phthalate, which is a potent inducer of peroxisomal /%oxidation system [9], on activities of acylCoA dehydrogenases in rat liver mitochondria, we noticed that the reducing activity of 2,6-dichloroindophenol in the presence of palmitoyl-CoA was markedly induced by the administration of di(2-ethylhexy1)phthalate. The increased rate of the dye reduction was due to the elevated activity of long-chain acyl-CoA hydrolase.In the present study, the induced hydrolase was found in the soluble fraction after the subcellular fractionation of rat livers. The enzyme was purified to a nearly homogeneous preparation and found to be a new enzyme with respect to its molecular and catalytic properties. MATERIALS AND METHODS MaterialsAcetyl-CoA and butyryl-CoA were prepared from the corresponding acid anhydrides. Other acyl-CoA derivatives were synthesized by the mixed anhydride method [lo] and purified as described previously [ l l , 121. CoA, bovine serum albumin and cytochrome c were from Sigma. Enzymes and coenzymes were purchased froin Boehringer. Analytical grades of fatty acids and other reagents were commercial products.Enzymes. Acyl-CoA oxidase (EC 1.3.-.-); adenylate kinase (EC 2.7.4.3); dlcohol dehydrogenase (EC 1.1.1.1); aldolase (EC 4.1.2.13); catalase (EC 1.11.1.6); citrate synthase (EC 4.1.3.7); glutamate dehydrogenase (EC 1.4.1.3); horseradish peroxidase (EC 1.11.1.7); lactate dehydrogendse (EC 1.1.1.27); long-chain acyl-CoA hydrolase (EC 3.1.2.2); malate dehydrogenase (EC 1.1.1.37) ; NADPH-cytochrome c reductase (EC 1.6.2.4); phosphorylase (EC 2.4.1.1). Animals and Subcellular FractionationMale Wistar rats (200-250 g) were fed a powdered diet (Oriental M, Tokyo) containing 2 (w/w) di(2-ethylhexy1)-phthalate for 2-4 weeks, when they were us...

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Section: Effects Qf Peroxisome Pvoliyeratorscontrasting

confidence: 87%

Induction of a Novel Long‐Chain Acyl‐CoA Hydrolase in Rat Liver by Administration of Peroxisome Proliferators

Miyazawa

Furuta

Hashimoto

1981

European Journal of Biochemistry

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“…A plausible hypothesis is therefore that one main metabolic function of peroxisomal fl-oxidation is to supplement mitochondrial fl-oxidation when the liver is faced with a high influx of fatty acids, as during feeding of high-fat diets, or during starvation (Ishii et al, 1980b). It is of particular significance when the diet contains appreciable quantities of fatty acids that are poorly oxidized by mitochondrial fl-oxidation.…”

Section: Capacities Of Peroxisomal and Mitochondrial Fioxidationmentioning

confidence: 99%

Effects of high-fat diets on hepatic fatty acid oxidation in the rat Isolation of rat liver peroxisomes by vertical-rotor centrifugation by using a self-generated, iso-osmotic, Percoll gradient

Neat¹,

Thomassen²,

Osmundsen³

1981

Biochemical Journal

165

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1. Rat liver peroxisomal fractions were isolated in iso-osmotic Percoll gradients by using vertical-rotor centrifugation. The fractions obtained with rats given various dietary treatments were characterized. 2. The effect on peroxisomal beta-oxidation of feeding 15% by wt. of dietary fat for 3 weeks was investigated. High-fat diets caused induction of peroxisomal beta-oxidation, but diets rich in very-long-chain mono-unsaturated fatty acids produced a more marked induction. 3. Peroxisomal beta-oxidation induced by diets rich in very-long-chain mono-unsaturated fatty acids can oxidize such acids. Trans-isomers of mono-unsaturated fatty acids are oxidized at rates that are faster than, or similar to, those obtained with corresponding cis-isomers. 4. Rates of oxidation of [14-14C]erucic acid by isolated rat hepatocytes isolated from rats fed on high-fat diets increased with the time on those diets in a fashion very similar to that previously reported for peroxisomal beta-oxidation [see Neat, Thomassen & Osmundsen (1980) Biochem, J. 186, 369-371]. 5. Total liver capacities for peroxisomal beta-oxidation (expressed as acetyl groups produced per min) were estimated to range from 10 to 30% of mitochondrial capacities, depending on dietary treatment and fatty acid substrate. A role is proposed for peroxisomal beta-oxidation in relation to the metabolism of fatty acids that are poorly oxidized by mitochondrial beta-oxidation, and, in general, as regards oxidation of fatty acids during periods of sustained high hepatic influx of fatty acids.

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“…Very recently, it has been shown that peroxisomes play an important role in lipid metabolism of fasted [3] or diabetic rats [4]. Ishii et al [5] showed that peroxisomal beta-oxidation is markedly stimulated by high fat diet.…”

Section: Introductionmentioning

confidence: 99%

Peroxisomal enzyme activities in regenerating liver of rats

Locci-Cubeddu

Bergamini

1982

Res. Exp. Med.

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The activities of five peroxisomal enzymes (fatty acyl-CoA oxidase, FAO; uricase, U; L-hydroxyacid oxidase, LHAO; D-aminoacid oxidase, DAO; and catalase, C and the triglyceride content were determined in the regenerating liver of rats after partial hepatectomy. The FAO activity was significantly increased on day 3. Thus, its rise followed the increase of the triglyceride content and preceded the disappearance of steatosis. For U and LHAO a similar progressive increase in activities was obtained on days 3, 5, and 7 of regeneration. DAO exhibited a highly significant increase on day 1. C increased on day 1 and then again after day 3. It is concluded that peroxisomal functions are not restored at parallel rates during liver regeneration.

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Physiological Role of Peroxisomal β-Oxidation in Liver of Fasted Rats

Cited by 94 publications

References 0 publications

Induction of a Novel Long‐Chain Acyl‐CoA Hydrolase in Rat Liver by Administration of Peroxisome Proliferators

Induction of a Novel Long‐Chain Acyl‐CoA Hydrolase in Rat Liver by Administration of Peroxisome Proliferators

Effects of high-fat diets on hepatic fatty acid oxidation in the rat Isolation of rat liver peroxisomes by vertical-rotor centrifugation by using a self-generated, iso-osmotic, Percoll gradient

Peroxisomal enzyme activities in regenerating liver of rats

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