[22] Assay of total complex and activity state of branched-chain α-keto acid dehydrogenase complex and of activator protein in mitochondria, cells, and tissues

1988 ◽  
pp. 175-189 ◽  
Author(s):  
Philip A. Patston ◽  
Joseph Espinal ◽  
Mark Beggs ◽  
Philip J. Randle
Keyword(s):  
Keto Acid ◽  
Acid Dehydrogenase ◽  
Activator Protein ◽  
Activity State ◽  
Branched Chain ◽  
Acid Dehydrogenase Complex ◽  
Dehydrogenase Complex

Nutritional and Hormonal Regulation of the Activity State of Hepatic Branched-Chain ?-Keto Acid Dehydrogenase Complex

1989 ◽  
Vol 573 (1 Alpha-Keto Ac) ◽  
pp. 306-313 ◽  
Author(s):  
ROBERT A. HARRIS ◽  
GARY W. GOODWIN ◽  
RALPH PAXTON ◽  
PAUL DEXTER ◽  
STEVEN M. POWELL ◽  
...  
Keyword(s):  
Hormonal Regulation ◽  
Keto Acid ◽  
Acid Dehydrogenase ◽  
Activity State ◽  
Branched Chain ◽  
Acid Dehydrogenase Complex ◽  
Dehydrogenase Complex

Activation of branched-chain alpha-keto acid dehydrogenase complex by exercise: effect of high-fat diet intake

1990 ◽  
Vol 68 (1) ◽  
pp. 161-165 ◽  
Author(s):  
Y. Shimomura ◽  
T. Suzuki ◽  
S. Saitoh ◽  
Y. Tasaki ◽  
R. A. Harris ◽  
...  
Keyword(s):  
Amino Acids ◽  
Branched Chain Amino Acids ◽  
Enzyme Complex ◽  
Keto Acid ◽  
High Fat ◽  
Acid Dehydrogenase ◽  
Activity State ◽  
Branched Chain ◽  
Acid Dehydrogenase Complex ◽  
Dehydrogenase Complex

The effect of exercise on the activity of branched-chain alpha-keto acid dehydrogenase complex in liver and muscle was studied in rats fed a high-fat (FAT) or a high-carbohydrate (CHO) diet. Both diet groups of rats were offered isoenergetic diets by a meal-feeding method and were trained by treadmill running. On the final day of the experiment, half of the rats in each diet group were exercised by 2 h of running just before they were killed. The activity state of the enzyme complex was elevated maximally by exercise in liver of rats fed the FAT diet but not in liver of rats fed the CHO diet, suggesting that catabolism of branched-chain amino acids in rat liver during exercise was enhanced by the FAT diet. The activity state of the enzyme complex in muscle was enhanced by exercise in both groups of rats, but a significant difference was not observed between the groups. The concentration of branched-chain amino acids was elevated in liver and muscle by exercise in both groups of rats, but the elevated levels in liver were lower in rats fed the FAT diet than in those fed the CHO diet. Serum branched-chain amino acid concentrations were significantly lower in rested rats fed the FAT diet than in those fed the CHO diet, and the leucine and isoleucine concentrations in the former were elevated by exercise, but the serum concentrations in the latter were not significantly affected by exercise. ATP and ADP concentrations in muscle were not significantly affected by either diet or exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Hepatic Branched-Chain .ALPHA.-Keto Acid Dehydrogenase Complex in Female Rats: Activation by Exercise and Starvation.

1999 ◽  
Vol 45 (3) ◽  
pp. 303-309 ◽  
Author(s):  
Rumi KOBAYASHI ◽  
Yoshiharu SHIMOMURA ◽  
Taro MURAKAMI ◽  
Naoya NAKAI ◽  
Megumi OTSUKA ◽  
...  
Keyword(s):  
Female Rats ◽  
Keto Acid ◽  
Acid Dehydrogenase ◽  
Branched Chain ◽  
Acid Dehydrogenase Complex ◽  
Dehydrogenase Complex

scholarly journals Effects of clofibric acid on the activity and activity state of the hepatic branched-chain 2-oxo acid dehydrogenase complex

1992 ◽  
Vol 285 (1) ◽  
pp. 167-172 ◽  
Author(s):  
Y Zhao ◽  
J Jaskiewicz ◽  
R A Harris
Keyword(s):  
Active Form ◽  
Clofibric Acid ◽  
Chow Diet ◽  
Acid Dehydrogenase ◽  
Low Protein ◽  
Activity State ◽  
Branched Chain ◽  
Acid Dehydrogenase Complex ◽  
Dehydrogenase Complex

Feeding clofibric acid to rats caused little or no change in total activity of the liver branched-chain 2-oxo acid dehydrogenase complex (BCODC). No change in mass of liver BCODC was detected by immunoblot analysis in response to dietary clofibric acid. No changes in abundance of mRNAs for the BCODC E1 alpha, E1 beta and E2 subunits were detected by Northern-blot analysis. Likewise, dietary clofibric acid had no effect on the activity state of liver BCODC (percentage of enzyme in the dephosphorylated, active, form) of rats fed on a chow diet. However, dietary clofibric acid greatly increased the activity state of liver BCODC of rats fed on a diet deficient in protein. No stable change in liver BCODC kinase activity was found in response to clofibric acid in either chow-fed or low-protein-fed rats. Clofibric acid had a biphasic effect on flux through BCODC in hepatocytes prepared from low-protein-fed rats. Stimulation of BCODC flux at low concentrations was due to clofibric acid inhibition of BCODC kinase, which in turn allowed activation of BCODC by BCODC phosphatase. Inhibition of BCODC flux at high concentrations was due to direct inhibition of BCODC by clofibric acid. The results suggest that the effects of clofibric acid in vivo on branched-chain amino acid metabolism can be explained by the inhibitory effects of this drug on BCODC kinase.

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