scholarly journals Influence of dietary leucine content on the activities of branched-chain amino acid aminotransferase (EC 2.6.1.42) and branched-chain α-keto acid dehydrogenase (EC 1.2.4.4) complex in tissues of preruminant lambs

1988 ◽  
Vol 59 (3) ◽  
pp. 475-483 ◽  
Author(s):  
Isabelle Papet ◽  
Nadia Lezebot ◽  
Francoise Barre ◽  
Maurice Arnal ◽  
Alfred E. Harper
Keyword(s):  
Amino Acid ◽  
Longissimus Dorsi ◽  
Keto Acid ◽  
Amino Acid Catabolism ◽  
Longissimus Dorsi Muscle ◽  
Acid Dehydrogenase ◽  
Branched Chain Amino Acid ◽  
Dorsi Muscle ◽  
Branched Chain ◽  
Low Rate

1. Branched-chain amino acid aminotransferase (EC 2.6.1.42; BCAAT) and branched-chain α-keto acid dehydrogenase (EC 1.2.4.4; BCKDH) activities were measured in preruminant lamb liver, longissimus dorsi muscle, kidney, jejunum and adipose tissue, 2 h after a meal with or without an excess of leucine.2. Skeletal muscle contained about 70% of the total basal BCAAT activities of the tissues studied whereas liver contained about 60% of the total BCKDH activities of these tissues.3. BCAAT activities were very low in preruminant lamb tissues. BCKDH was more phosphorylated in tissues of preruminant lambs than in rats, especially in liver. These low catalytic potentialities might contribute to a low rate of branched-chain amino acid catabolism in sheep.4. Ingestion of an excess of leucine led to an increase in liver and jejunum BCAAT activities and activation of BCKDH in jejunum.

Glucocorticoid-mediated activation of muscle branched-chain alpha-keto acid dehydrogenase in vivo

1987 ◽  
Vol 252 (3) ◽  
pp. E396-E407 ◽  
Author(s):  
K. P. Block ◽  
W. B. Richmond ◽  
W. B. Mehard ◽  
M. G. Buse
Keyword(s):  
Skeletal Muscle ◽  
Amino Acid ◽  
Active Enzyme ◽  
Acid Oxidation ◽  
Enzyme Complex ◽  
Keto Acid ◽  
Amino Acid Oxidation ◽  
Acid Dehydrogenase ◽  
Branched Chain Amino Acid ◽  
Branched Chain

Muscle branched-chain alpha-keto acid dehydrogenase, the rate-limiting enzyme for branched-chain amino acid oxidation in skeletal muscle, was measured after treatment of rats with glucocorticoids. Cortisone treatment (10 mg X 100 g body wt-1 X day-1 for 2–5 days) resulted in an approximate doubling of the percentage of active enzyme. To further characterize this effect, the enzyme complex was measured 4 h after the intraperitoneal injection of 6 alpha-methylprednisolone, a water-soluble glucocorticoid with rapid onset effects. The percentage of active enzyme increased linearly as the dose of methylprednisolone was increased from 0.125 to 12.5 mg/100 g body wt, while total enzyme activity was unchanged. Administration of insulin with glucose had no significant effect on the activity of the enzyme. However, treatment of rats with insulin and glucose after methylprednisolone administration partially blocked branched-chain alpha-keto acid dehydrogenase activation. The activity of the enzyme complex was correlated with the concentration of leucine in plasma and muscle. Activation of skeletal muscle branched-chain alpha-keto acid dehydrogenase by increased glucocorticoids may play a role in the acceleration of branched-chain amino acid oxidation observed during severe stress.

Branched-chain amino acid metabolism in rat muscle: abnormal regulation in acidosis

1987 ◽  
Vol 252 (6) ◽  
pp. E712-E718 ◽  
Author(s):  
R. C. May ◽  
Y. Hara ◽  
R. A. Kelly ◽  
K. P. Block ◽  
M. G. Buse ◽  
...  
Keyword(s):  
Metabolic Acidosis ◽  
Amino Acid ◽  
Acid Metabolism ◽  
Muscle Protein ◽  
Total Activity ◽  
Keto Acid ◽  
Acid Dehydrogenase ◽  
Branched Chain Amino Acid ◽  
Pathological Conditions ◽  
Branched Chain

Branched-chain amino acid (BCAA) metabolism is frequently abnormal in pathological conditions accompanied by chronic metabolic acidosis. To study how metabolic acidosis affects BCAA metabolism in muscle, rats were gavage fed a 14% protein diet with or without 4 mmol NH4Cl X 100 g body wt-1 X day-1. Epitrochlearis muscles were incubated with L-[1-14C]-valine and L-[1-14C]leucine, and rates of decarboxylation, net transamination, and incorporation into muscle protein were measured. Plasma and muscle BCAA levels were lower (P less than 0.05) in acidotic rats. Rates of valine and leucine decarboxylation and net transamination were higher (P less than 0.05) in muscles from acidotic rats; these differences were associated with a 79% increase in the total activity of branched-chain alpha-keto acid dehydrogenase and a 146% increase in the activated form of the enzyme. We conclude that acidosis affects the regulation of BCAA metabolism by enhancing flux through the transaminase and by directly stimulating oxidative catabolism through activation of branched-chain alpha-keto acid dehydrogenase.

Octanoic acid promotes branched-chain amino acid catabolisms via the inhibition of hepatic branched-chain alpha-keto acid dehydrogenase kinase in rats

Metabolism ◽  
2015 ◽  
Vol 64 (9) ◽  
pp. 1157-1164 ◽  
Author(s):  
Yoshihiro Kadota ◽  
Takanari Toyoda ◽  
Mayumi Hayashi-Kato ◽  
Yasuyuki Kitaura ◽  
Yoshiharu Shimomura
Keyword(s):  
Amino Acid ◽  
Octanoic Acid ◽  
Keto Acid ◽  
Acid Dehydrogenase ◽  
Branched Chain Amino Acid ◽  
Branched Chain

scholarly journals Transcriptional hallmarks of cancer cell lines reveal an emerging role of branched chain amino acid catabolism

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Ieva Antanavičiūtė ◽  
Valeryia Mikalayeva ◽  
Ieva Ceslevičienė ◽  
Gintarė Milašiūtė ◽  
Vytenis Arvydas Skeberdis ◽  
...  
Keyword(s):  
Amino Acid ◽  
Cell Lines ◽  
Cancer Cell ◽  
Cancer Cell Lines ◽  
Amino Acid Catabolism ◽  
Hallmarks Of Cancer ◽  
Branched Chain Amino Acid ◽  
Branched Chain
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