Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.3.9 (glucose-6-phosphatase)
 3,081 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It is established that in embryos incubated until the early blastula stage in the solution of insulin with addition of cycloheximide or puromycin, there is neither a decrease in the hexokinase and glucose-61 phosphate dehydrogenase activities nor an increase in the phosphofructokinase activity, as it is shown under the influence of insulin only. Puromycin removes an inhibitory effect of insulin on the glucose-6-phosphatase activity, and actinomycin D removes this influence with respect to glucose-6-phosphate dehydrogenase and glucose-6-phosphatase activities. The addition of antibiotics removes inhibition of the hexokinase, glucose-6-phosphate dehydrogenase and glucose-6-phosphatase activities by the hormone in the unfertilized eggs as well. Actinomycin D alone inhibits the hexokinase and activates the phosphofructokinase activities in the embryos and eggs, puromycin decreases their hexokinase activity and cycloheximide has the same effect on the glucose-6-phosphatase activity in the embryos only.
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PMID:[Effect of insulin on activity of carbohydrate metabolism enzymes in loach embryos in early development]. 19 74

We have established an experimental system in rats in which the lipogenic capacity of adipose tissue was decreased in vivo by prolonged fasting, and restored in vitro by glucose together with insulin or vanadate. Incubation of fasted adipose explants for 5 h at 37 C with 2 mM glucose alone did not elevate lipogenic capacity. However, glucose with insulin (17 nM) or vanadate (100 microM), led, respectively, to 2.2- and 8- to 10-fold elevation. Actinomycin D (50 microM) completely blocked this increase, while low concentrations (ED50 = 4.0 +/- 0.4 microM) of vanadate potentiated it. Neither insulin nor vanadate elevated fasted adipose explants' lipogenic capacity in the absence of glucose, or in the presence of the nonmetabolizable glucose analog 3-O-methylglucose. Upon replacing glucose with 2-deoxyglucose (1 mM), a glucose analog that undergoes phosphorylation to 2-deoxyglucose-6-phosphate with no further metabolism, vanadate was nearly as potent as with glucose in elevating lipogenic capacity. Vanadate was superior to insulin in increasing glucose-6-phosphate level in fasted-adipose explants. Adipose glucose-6-phosphatase activity was inhibited by vanadate (IC50 = 7.0 +/- 0.4 microM). We have concluded that glucose-6-phosphate is the key metabolite of glucose involved in the transcriptionally regulated elevation of lipogenic capacity of fasted adipose explants. Vanadate has a more profound effect than insulin, as it elevates glucose-6-phosphate to higher levels and the subsequent increase in lipogenic capacity is four to five times greater than that induced by insulin. The mechanism involved is the combined action of vanadate in enhancing glucose entry and in inhibiting dephosphorylation of endogenously formed glucose-6-phosphate. The latter effect is not exerted by insulin.
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PMID:Vanadate elevates lipogenicity of starved rat adipose tissue: mechanism of action. 956 66

The cortisone-induced de novo synthesis of liver glucose-6-phosphatase, fructose-1, 6-diphosphatase, aldolase, and lactic dehydrogenase was prevented by injections of Actinomycin D in the rat. In the in vitro assay systems, addition of actinomycin exerted no effect on the enzyme activities examined. The evidence favors the concept that the increased gluconeogenesis induced by corticoids entails at a certain stage an increased rate in the synthesis of gluconeogenic enzymes.
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PMID:ACTINOMYCIN: INHIBITION OF CORTISONE-INDUCED SYNTHESIS OF HEPATIC GLUCONEOGENIC ENZYMES. 1405 5

Fructose consumption has increased dramatically but little is known about mechanisms regulating the intestinal fructose transporter GLUT5 in vivo. In neonatal rats, GLUT5 can be induced only by luminal fructose and only after 14 days of age, unless the gut is primed with dexamethasone prior to fructose perfusion. To elucidate the mechanisms underlying dexamethasone modulation of GLUT5 development, we first identified the receptor mediating its effects then determined whether those effects were genomic. The glucocorticoid receptor (GR) antagonist RU486 dose-dependently prevented the dexamethasone-mediated effects on body weight, intestinal arginase2 (a known GR-regulated gene) and GLUT5. In contrast, an antagonist of the mineralocorticoid receptor as well as agonists of progesterone (PR) and pregnane-X (PXR) receptors did not block the effects of dexamethasone. These receptor antagonists and agonists had no effect on the intestinal glucose transporter SGLT1. Translocation of the GR into the enterocyte nucleus occurred only in dexamethasone-injected pups perfused with fructose, was accompanied by marked increases in brush border GLUT5 abundance, and was blocked by RU486. A priming duration of approximately 24 h is optimal for induction but actinomycin D injection before dexamethasone priming prevented dexamethasone from allowing luminal fructose to induce GLUT5. Actinomycin D had no effect on dexamethasone-independent fructose-induced increases in glucose-6-phosphatase mRNA abundance, suggesting that it did not prevent fructose-induction of GLUT5, but instead prevented dexamethasone-induced synthesis of an intermediate required by fructose for GLUT5 regulation. In suckling rats < 14 days old, developmental regulation of transporters may involve cross-talk between hormonal signals modulating intestinal maturation and nutrient signals regulating specific transporters.
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PMID:Developmental reprogramming of rat GLUT5 requires glucocorticoid receptor translocation to the nucleus. 1866 40

The differentiated effects of phenobarbital treatment on liver microsomal enzymes have been further studied. The relationship between the resulting decrease in the specific glucose-6-phosphatase activity and the enhancement of formation of endoplasmic reticulum membranes with high drug-hydroxylating activity has been investigated with biochemical and histochemical methods. Biochemically and histochemically demonstrable glucose-6-phosphatase activity was found to be present in all endoplasmic reticulum membranes, including the phenobarbital-induced smooth-surfaced proliferates, even though there was an over-all decrease in activity. Actinomycin D did not inhibit the decrease in glucose-6-phosphatase activity. The findings are discussed with reference to the enzyme-membrane relationship in phenobarbital induction.
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PMID:On the relationship of liver glucose-6-phosphatase to the proliferation of endoplasmic reticulum in phenobarbital induction. 1986 99