The gluconeogenic enzyme PCK1 phosphorylates INSIG1/2 for lipogenesis

Nature ◽  
2020 ◽  
Vol 580 (7804) ◽  
pp. 530-535 ◽  
Author(s):  
Daqian Xu ◽  
Zheng Wang ◽  
Yan Xia ◽  
Fei Shao ◽  
Weiya Xia ◽  
...  
Keyword(s):  
Gluconeogenic Enzyme

Induction of renal phosphoenolpyruvate carboxykinase mRNA: suppressive effect of glucose

1989 ◽  
Vol 257 (1) ◽  
pp. F145-F151
Author(s):  
A. S. Pollock
Keyword(s):  
Metabolic Acidosis ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Suppressive Effect ◽  
Oral Glucose ◽  
Prolonged Fasting ◽  
Glucose Loading ◽  
Glucose Administration ◽  
Liver And Kidney ◽  
Gluconeogenic Enzyme ◽  
Effect Of Glucose

The mRNA for the important gluconeogenic enzyme phosphoenolpyruvate carboxykinase (GTP) (PEPCK; EC 4.1.1.32) is expressed in liver and kidney. In the kidney, acidosis is a unique and potent stimulus, whereas insulin, the major counterregulatory hormone of gluconeogenesis, has no effect. In this study, we find that oral glucose administration to rats rapidly decreases the abundance of renal PEPCK mRNA by 50–72%. This reduction takes place in normal euglycemic, in insulin-induced hypoglycemic, and in streptozotocin-induced hyperglycemic diabetic animals. The effect of glucose is not seen in the presence of metabolic acidosis, whether induced by NH4Cl or by prolonged fasting. Therefore, it appears that oral glucose loading is a physiological suppressor of renal PEPCK message abundance, although not in acidosis.

scholarly journals Alcoholic Stem Extract ofCoscinium fenestratumRegulates Carbohydrate Metabolism and Improves Antioxidant Status in Streptozotocin–Nicotinamide Induced Diabetic Rats

2005 ◽  
Vol 2 (3) ◽  
pp. 375-381 ◽  
Author(s):  
I. R. Punitha ◽  
K. Rajendran ◽  
Arun Shirwaikar ◽  
Annie Shirwaikar
Keyword(s):  
Carbohydrate Metabolism ◽  
Antioxidant Status ◽  
Diabetic Rats ◽  
Antidiabetic Activity ◽  
Glutathione Synthetase ◽  
Alcoholic Extract ◽  
Enzymatic Antioxidants ◽  
Stem Extract ◽  
Gluconeogenic Enzyme ◽  
Glucose 6 Phosphate Dehydrogenase

Alcoholic extract of the stems ofCoscinium fenestratum, a medicinal plant indigenous to India and Sri Lanka used in ayurveda and siddha medicine for treating diabetes, was studied for its carbohydrate metabolism effect and antioxidant status in streptozotocin–nicotinamide induced type 2 diabetic rats. Oral administration ofC. fenestratumstem extract in graded doses caused a significant increase in enzymatic antioxidants such as catalase, superoxide dismutase, glutathione synthetase, peroxidase, and glutathione peroxidase and in the nonenzymatic antioxidants ascorbic acid, ceruloplasmin and tocopherol. Effects of alcoholic extract on glycolytic enzymes such as glucose-6-phosphate dehydrogenase, lactate dehydrogenase and hexokinase showed a significant increase in their levels, whereas a significant decrease was observed in the levels of gluconeogenic enzyme, glucose-6-phosphatase and alanine aminotransferase in treated diabetic rats. Serum creatinine and urea levels also declined significantly. This investigation demonstrates significant antidiabetic activity ofC. fenestratum.

Fluctuations in rat liver alanine-amino-transferase activity during experimental nippostrongylosis

Parasitology ◽  
1989 ◽  
Vol 98 (2) ◽  
pp. 301-306
Author(s):  
Lucy J. Robertson
Keyword(s):  
Immune Response ◽  
Primary Infection ◽  
Parasitic Infection ◽  
Transferase Activity ◽  
Nippostrongylus Brasiliensis ◽  
Alanine Amino Transferase ◽  
A Value ◽  
Gluconeogenic Enzyme ◽  
Alt Activity

SUMMARYThe activity of the gluconeogenic enzyme, alanine-amino-transferase (ALT), in a preparation from the liver of rats was studied by means of an in vitro assay throughout the course of a primary infection of Nippostrongylus brasiliensis, established by a subcutaneous injection of approximately 4000 3rd-stage larvae. The activity was measured on days 1–14 p.i. in both uninfected and infected rats and a marked pattern in the enzyme's activity was observed. In infected rats, the activity increased from 1·46±0·19 U/g liver on day 1 p.i. to a peak on day 4 p.i. of 10·75±1·62 U/g liver, then decreased to a trough of 0·44±0·18 U/g liver on day 10 p.i. before returning to original levels by day 14 p.i., by which time the infection had been largely eliminated. In uninfected rats the activity of the liver enzyme remained constant throughout this period with a value of 2·54±0·12 U/g liver. The activity of the enzyme in vitro was found to be related to the size of the inoculum on days 4 and 10 p.i. It was proposed that these observations could be due to either (1) a direct effect of the parasite, or (2) a consequence of the host immune response to the infection. In order to investigate the second proposition more fully, liver ALT activity was investigated by in vitro assay on selected days p.i. in rats experiencing a secondary N. brasiliensis infection. In these rats the liver ALT activity was observed to reach a peak on day 2 p.i., with an activity of 3·87 ± 0-28 U/g liver, and a trough on day 4 p.i. with an activity of 0·11 ±0·03 U/g liver, returning to similar levels to those measured in uninfected rats by day 7 p.i. When serum prepared from rats having secondary N. brasiliensis infections collected on day 4 p.i. was added to the assay, a reduction in the activity of liver ALT activity from both the infected and uninfected rats was measured by in vitro assay. The results are discussed in relation to protein metabolism and gluconeogenesis in rats infected with N. brasiliensis, and also in relation to the host’s immune response to the parasitic infection.

Systemic oscillator-driven and nutrient-responsive hormonal regulation of daily expression rhythms for gluconeogenic enzyme genes in the mouse liver

2019 ◽  
Vol 36 (5) ◽  
pp. 591-615
Author(s):  
Akiko Taira ◽  
Emiko Arita ◽  
Eriko Matsumoto ◽  
Ayano Oohira ◽  
Katsuro Iwase ◽  
...  
Keyword(s):  
Hormonal Regulation ◽  
Mouse Liver ◽  
Gluconeogenic Enzyme

scholarly journals The Gluconeogenic Enzyme Fructose-1,6-Bisphosphatase Is Dispensable for Growth of the Yeast Yarrowia lipolytica in Gluconeogenic Substrates

2008 ◽  
Vol 7 (10) ◽  
pp. 1742-1749 ◽  
Author(s):  
Raquel Jardón ◽  
Carlos Gancedo ◽  
Carmen-Lisset Flores
Keyword(s):  
Yarrowia Lipolytica ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Isocitrate Lyase ◽  
Carbon Sources ◽  
Subcellular Fractionation ◽  
Fructose 1,6 Bisphosphatase ◽  
Genes Encoding ◽  
Key Enzyme ◽  
Gluconeogenic Enzyme ◽  
Fructose 1,6 Bisphosphate

ABSTRACT The genes encoding gluconeogenic enzymes in the nonconventional yeast Yarrowia lipolytica were found to be differentially regulated. The expression of Y. lipolytica FBP1 (YlFBP1) encoding the key enzyme fructose-1,6-bisphosphatase was not repressed by glucose in contrast with the situation in other yeasts; however, this sugar markedly repressed the expression of YlPCK1, encoding phosphoenolpyruvate carboxykinase, and YlICL1, encoding isocitrate lyase. We constructed Y. lipolytica strains with two different disrupted versions of YlFBP1 and found that they grew much slower than the wild type in gluconeogenic carbon sources but that growth was not abolished as happens in most microorganisms. We attribute this growth to the existence of an alternative phosphatase with a high Km (2.3 mM) for fructose-1,6-bisphosphate. The gene YlFBP1 restored fructose-1,6-bisphosphatase activity and growth in gluconeogenic carbon sources to a Saccharomyces cerevisiae fbp1 mutant, but the introduction of the FBP1 gene from S. cerevisiae in the Ylfbp1 mutant did not produce fructose-1,6-bisphosphatase activity or growth complementation. Subcellular fractionation revealed the presence of fructose-1,6-bisphosphatase both in the cytoplasm and in the nucleus.

scholarly journals A Toxoplasma gondii Gluconeogenic Enzyme Contributes to Robust Central Carbon Metabolism and Is Essential for Replication and Virulence

2015 ◽  
Vol 18 (2) ◽  
pp. 210-220 ◽  
Author(s):  
Martin Blume ◽  
Richard Nitzsche ◽  
Ulrich Sternberg ◽  
Motti Gerlic ◽  
Seth L. Masters ◽  
...  
Keyword(s):  
Toxoplasma Gondii ◽  
Carbon Metabolism ◽  
Central Carbon Metabolism ◽  
Central Carbon ◽  
Gluconeogenic Enzyme

Adaptation, constraint, and the function of the gluconeogenic pathway

1988 ◽  
Vol 66 (5) ◽  
pp. 1059-1068 ◽  
Author(s):  
Thomas W. Moon
Keyword(s):  
De Novo ◽  
Activity Level ◽  
Adaptive Responses ◽  
Muscle Lactate ◽  
Glucose Levels ◽  
Blood Glucose Levels ◽  
Metabolic Sequence ◽  
Gluconeogenic Enzyme ◽  
Quantitative Changes

Gluconeogenesis is responsible for the de novo synthesis of glucose (and glycogen) from precursors including lactate, amino acids, glycerol, and fructose. This metabolic sequence is highly constrained by design features including enzyme composition and tissue localization, but demonstrates a variety of adaptive patterns which are critical to the maintenance of blood glucose levels optimal for animal function. This review identifies the adaptive responses of gluconeogenesis when glucose levels are challenged by changes in diet (both quality and quantity) and in activity level, and by environmental disturbances. Five adaptive patterns are identified: (i) quantitative changes in gluconeogenic enzyme activities and their subcellular distribution; (ii) alterations in tissue demand for glucose; (iii) existence of in situ skeletal muscle lactate cycling; (iv) quantity and type of gluconeogenic precursors; and (v) regulation of gluconeogenesis. The validity of the omnivorous mammalian model in our understanding of gluconeogenesis is discussed.

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