Characterization of the isozymes of pyruvate dehydrogenase phosphatase: implications for the regulation of pyruvate dehydrogenase activity

2003 ◽  
Vol 1652 (2) ◽  
pp. 126-135 ◽  
Author(s):  
Tatiana Karpova ◽  
Svitlana Danchuk ◽  
Elena Kolobova ◽  
Kirill M. Popov
Keyword(s):  
Dehydrogenase Activity ◽  
Pyruvate Dehydrogenase ◽  
Pyruvate Dehydrogenase Phosphatase

scholarly journals A comparison of the regulation of pyruvate dehydrogenase in mitochondria from rat brain and liver

1975 ◽  
Vol 150 (3) ◽  
pp. 397-403 ◽  
Author(s):  
R Jope ◽  
J P Blass
Keyword(s):  
Rat Brain ◽  
Dehydrogenase Activity ◽  
Pyruvate Dehydrogenase ◽  
Active Form ◽  
Energy Charge ◽  
Liver Mitochondria ◽  
Brain Mitochondria ◽  
Ruthenium Red ◽  
Rat Brain And Liver ◽  
Pyruvate Dehydrogenase Phosphatase

The total activity of pyruvate dehydrogenase in mitochondria isolated from rat brain and liver was 53.5 and 14.2nmol/min per mg of protein respectively. Pyruvate dehydrogenase in liver mitochondria incubated for 4 min at 37 degrees C with no additions was 30% in the active form and this activity increased with longer incubations until it was completely in the active form after 20 min. Brain mitochondrial pyruvate dehydrogenase activity was initially high and did not increase with addition of Mg2+ plus Ca2+ or partially purified pyruvate dehydrogenase phosphatase or with longer incubations. The proportion of pyruvate dehydrogenase in the active form in both brain and liver mitochondria changed inversely with changes in mitochondrial energy charge, whereas total pyruvate dehydrogenase did not change. The chelators citrate, isocitrate, EDTA, ethanedioxybis(ethylamine)tetra-acetic acid and Ruthenium Red each lowered pyruvate dehydrogenase activity in brain mitochondria, but only citrate and isocitrate did so in liver mitochondria. These chelators did not affect the energy charge of the mitochondria. Mg2+ plus Ca2+ reversed the pyruvate dehydrogenase inactivation in liver, but not brain, mitochondria. The regulation of the activation-inactivation of pyruvate dehydrogenase in mitochondria from rat brain and liver with respect to energy charge is similar and may be at least partially regulated by this parameter, and the effects of chelators differ in the two types of mitochondria.

scholarly journals Mechanism of activation of pyruvate dehydrogenase by mitogens in pig lymphocytes

1983 ◽  
Vol 216 (2) ◽  
pp. 359-367 ◽  
Author(s):  
E Baumgarten ◽  
M D Brand ◽  
T Pozzan
Keyword(s):  
Dehydrogenase Activity ◽  
Concanavalin A ◽  
Pyruvate Dehydrogenase ◽  
Pyruvate Dehydrogenase Kinase ◽  
Ionophore A23187 ◽  
Intact Cells ◽  
Permeabilized Cells ◽  
Maximal Activation ◽  
Pyruvate Dehydrogenase Phosphatase

The activity of pyruvate dehydrogenase in extracts of pig mesenteric lymphocytes was measured under different preincubation conditions. The mitogens concanavalin A and ionophore A23187 both increased pyruvate dehydrogenase activity. In both cases activation required extracellular Ca2+. Digitonin-permeabilized cells required 0.5 microM free Ca2+ for half-maximal activation of pyruvate dehydrogenase. The stimulation by concanavalin A in intact cells was probably not due to changes in effectors of pyruvate dehydrogenase kinase. This evidence suggests that activation of pyruvate dehydrogenase is by Ca2+ activation of pyruvate dehydrogenase phosphatase and supports the view that the cytoplasmic free [Ca2+] rises to something less than 1 microM on stimulation with mitogens.

Pyruvate dehydrogenase activity in cardiac mitochondria from genetically diabetic mice

Diabetes ◽  
1985 ◽  
Vol 34 (11) ◽  
pp. 1075-1081 ◽  
Author(s):  
T. H. Kuo ◽  
F. Giacomelli ◽  
J. Wiener ◽  
K. Lapanowski-Netzel
Keyword(s):  
Dehydrogenase Activity ◽  
Pyruvate Dehydrogenase ◽  
Diabetic Mice ◽  
Cardiac Mitochondria ◽  
Genetically Diabetic Mice

scholarly journals FoxO1 inhibition alleviates type 2 diabetes-related diastolic dysfunction by increasing myocardial pyruvate dehydrogenase activity

Cell Reports ◽  
2021 ◽  
Vol 35 (1) ◽  
pp. 108935
Author(s):  
Keshav Gopal ◽  
Rami Al Batran ◽  
Tariq R. Altamimi ◽  
Amanda A. Greenwell ◽  
Christina T. Saed ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Diastolic Dysfunction ◽  
Dehydrogenase Activity ◽  
Pyruvate Dehydrogenase

scholarly journals Starvation and Diabetes Reduce the Amount of Pyruvate Dehydrogenase Phosphatase in Rat Heart and Kidney

Diabetes ◽  
2003 ◽  
Vol 52 (6) ◽  
pp. 1371-1376 ◽  
Author(s):  
B. Huang ◽  
P. Wu ◽  
K. M. Popov ◽  
R. A. Harris
Keyword(s):  
Pyruvate Dehydrogenase ◽  
Rat Heart ◽  
Pyruvate Dehydrogenase Phosphatase

The relationship between human skeletal muscle pyruvate dehydrogenase phosphatase activity and muscle aerobic capacity

2011 ◽  
Vol 111 (2) ◽  
pp. 427-434 ◽  
Author(s):  
Lorenzo K. Love ◽  
Paul J. LeBlanc ◽  
J. Greig Inglis ◽  
Nicolette S. Bradley ◽  
Jon Choptiany ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Protein Content ◽  
Endurance Training ◽  
Aerobic Capacity ◽  
Pyruvate Dehydrogenase ◽  
Human Skeletal Muscle ◽  
Citrate Synthase ◽  
Tricarboxylic Acid Cycle ◽  
Carbohydrate Oxidation ◽  
Pyruvate Dehydrogenase Phosphatase

Pyruvate dehydrogenase (PDH) is a mitochondrial enzyme responsible for regulating the conversion of pyruvate to acetyl-CoA for use in the tricarboxylic acid cycle. PDH is regulated through phosphorylation and inactivation by PDH kinase (PDK) and dephosphorylation and activation by PDH phosphatase (PDP). The effect of endurance training on PDK in humans has been investigated; however, to date no study has examined the effect of endurance training on PDP in humans. Therefore, the purpose of this study was to examine differences in PDP activity and PDP1 protein content in human skeletal muscle across a range of muscle aerobic capacities. This association is important as higher PDP activity and protein content will allow for increased activation of PDH, and carbohydrate oxidation. The main findings of this study were that 1) PDP activity ( r2 = 0.399, P = 0.001) and PDP1 protein expression ( r2 = 0.153, P = 0.039) were positively correlated with citrate synthase (CS) activity as a marker for muscle aerobic capacity; 2) E1α ( r2 = 0.310, P = 0.002) and PDK2 protein ( r2 = 0.229, P =0.012) are positively correlated with muscle CS activity; and 3) although it is the most abundant isoform, PDP1 protein content only explained ∼18% of the variance in PDP activity ( r2 = 0.184, P = 0.033). In addition, PDP1 in combination with E1α explained ∼38% of the variance in PDP activity ( r2 = 0.383, P = 0.005), suggesting that there may be alternative regulatory mechanisms of this enzyme other than protein content. These data suggest that with higher muscle aerobic capacity (CS activity) there is a greater capacity for carbohydrate oxidation (E1α), in concert with higher potential for PDH activation (PDP activity).

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