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

The binding characteristics of hGH to Golgi and liver plasma membranes isolated from normal adult female rats have been compared to assess the biological differences between the Golgi and plasma membrane receptor. The effect of cations and the time course of binding were qualitatively similar for both Golgi and plasma membranes. The Golgi membranes from normal rats exhibited maximum binding at pH 6-7 compared to 5-6 for other membrane fractions. The highest apparent affinities (approx. 1 x 10(9) M-1) for hGH were observed in the light Golgi membranes from normal rats and the light and intermediate Golgi membranes from ethanol treated rats. The lowest apparent affinities (0.026 -0.1 x 10(9)M-1 if determined by competitive binding curves or 0.07 - 0.32 x 10(9)M-1 by Scatchard plots) for hGH were observed in plasma membranes isolated by either Neville's or Ray's method or a combination of both methods. The hGH receptors were determined to be lactogenic by competitive binding curves. The affinities of Golgi membranes were not affected by alterations in isolation procedures. Ethanol treatment of the rats prior to sacrifice and membrane isolation resulted in linear Scatchard plots for hGH binding to Golgi membranes compared to curved Scatchard plots for the Golgi membranes of normal rats. The marker enzyme activities of glucose-6-phosphatase and adenylate cyclase were lower in Golgi from ethanol treated rats while the galactosyl transferase activity increased in lighter golgi fractions from ethanol treated rats.
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PMID:Comparison of human growth hormone binding to rat liver plasma and Golgi membranes. 627 78

The effect of dietary fat upon ethanol metabolism was studied in rats. Wistar strain male rats were divided into four groups according to diet, namely alcohol-high fat, alcohol-low fat, control-high fat, and control-low fat. After 4 weeks of feeding, blood ethanol levels following an intraperitoneal injection of 0.2 g ethanol/100 g of body weight were measured. The disappearance rate of blood ethanol was faster and the metabolic rate of ethanol was significantly greater in the alcohol-high fat group compared to the alcohol-low fat or non-alcoholic groups. Microsomal enzymes, such as the microsomal ethanol-oxidizing system, aniline hydroxylase, and glucose-6-phosphatase, were significantly higher in the alcohol-high fat group than in the alcohol-low fat or non-alcoholic groups. The ethanol uptake rate of the isolated perfused liver was increased significantly in the alcoholic groups. In the alcoholic rats, the high fat group showed significantly higher uptake than the low fat group. Although the ethanol uptake rate after 4-methylpyrazole treatment was not significantly different among the four groups, its fraction of the total ethanol uptake was increased significantly in the alcohol-high fat group. These results suggest that high fat diets accelerate ethanol metabolism through the microsomal ethanol-oxidizing system.
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PMID:Effect of dietary fat upon ethanol metabolism in rats. 648 77

Ethanol-induced birth defects may be metabolic or structural. The aim of this study was to examine the effects of prenatal ethanol exposure on the ontogeny of gluconeogenic enzymes. Female rats were fed either liquid diets containing 35% ethanol-derived calories or control diets with isocaloric substitution of corn oil for ethanol. Control diets were pair-fed or given ad libitum. Animals were acclimated to the liquid diets for 7 weeks prior to breeding and the diets were continued through gestation. On day 21, at 4 hr post-caesarean section, ethanol-exposed pups exhibited reduced activities of phosphoenolpyruvate carboxykinase and glucose-6-phosphatase when compared to pair-fed and ad libitum controls. It is concluded that prenatal ethanol exposure delays or impairs the development of gluconeogenic enzymes.
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PMID:Effects of maternal ethanol consumption on the ontogeny of gluconeogenesis in the perinatal period. 667 58

Coccinia indica leaves were extracted with 60% ethanol, solvents were evaporated and the residue was suspended in water. This suspension was administered orally at a dose of 200 mg/kg body wt. after 18 h of fasting to normal fed and streptozotocin-induced male diabetic rats (180-250 g). After 90 min the rats were killed, and blood-glucose, hepatic glucose-6-phosphatase, fructose-1,6-bisphosphatase and glucose-6-phosphate dehydrogenase (G6PDH) and red-cell G6PDH were assayed. Blood sugar was depressed by 23% (P < 0.01) and 27% (P < 0.001) in the normal fed and streptozotocin-diabetic rats respectively compared with controls which were given distilled water. Hepatic glucose-6-phosphatase and fructose-1,6-bisphosphatase activities were depressed by 32% (P < 0.001) 30% (P < 0.05) respectively in the streptozotocin-diabetic rats, compared with 19% (P < 0.02) and 20% (P < 0.01) depression in the normal fed controls, whereas both the red-cell and hepatic G6PDH activities were found to be elevated by feeding the extract in the streptozotocin-diabetic and in the normal fed controls. Similar results were obtained with the 95%-ethanolic extract of Momordica charantia. Taken together, these results indicate that Coccinia indica and Momordica charantia extracts lowered blood glucose by depressing its synthesis, on the one hand through depression of the key gluconeogenic enzymes glucose-6-phosphatase and fructose-1,6-bisphosphatase and on the other by enhancing glucose oxidation by the shunt pathway through activation of its principal enzyme G6PDH.
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PMID:Hypoglycaemic activity of Coccinia indica and Momordica charantia in diabetic rats: depression of the hepatic gluconeogenic enzymes glucose-6-phosphatase and fructose-1,6-bisphosphatase and elevation of both liver and red-cell shunt enzyme glucose-6-phosphate dehydrogenase. 838 27

Preliminary data have been obtained indicating that glucose-6-phosphatase is inactivated upon preincubation with 447 and 224 mM acetaldehyde for 30 min at room temperature, resulting in a loss of 67% and 33% of the original activity, respectively. The reaction with acetaldehyde is rapid because 44% of the enzymic activity is lost in 5 min. Comparable quantities of ethanol inhibit the enzyme to the extent of 11%, indicating a very slight, statistically insignificant organic solvent effect. Because chronic alcoholics present a clinical picture of hypoglycemia, hyperuricemia, reduced gluconeogenesis, and lactic acidemia, it is hypothesized that glucose-6-phosphatase may be a focal enzyme whose inactivation may be related to each of the disorders. Glucose-6-phosphatase is the terminal key enzyme in the gluconeogenesis pathway leading to increased blood glucose. Inhibition thereof may explain both the alternate reduction of pyruvate with concommittent increased formation of lactic acid, and the increase in the pentose phosphate pathway leading to hyperuricemia (as also observed in von Gierke's disease).
Alcohol
PMID:A hypothesis linking hypoglycemia, hyperuricemia, lactic acidemia, and reduced gluconeogenesis in alcoholics to inactivation of glucose-6-phosphatase activity by acetaldehyde. 894 49

This study was conducted to identify the nature of a glycogen-associated compound that had been shown to inhibit glucose-6 phosphatase in vitro. Glycogen was purified from the liver of fed rats by potassium hydroxyde digestion and ethanol precipitation. It inhibited glucose-6 phosphatase in microsomes isolated from rats deprived of food for 48 h. Two glycogen-associated fractions were purified by anion-exchange chromatography on DOWEX 1 (200-400 mesh). These fractions inhibited microsomal glucose-6-phosphatase activity in vitro (80 +/- 2 and 76 +/- 3% of control, respectively). After chromatography, glycogen was no longer inhibitory (101 +/- 3% of control). Because glycogen is associated with endoplasmic reticulum membranes in the liver, we tested the hypothesis that lipids could be involved in the inhibitory process. Lipids were extracted from glycogen by Folch's method and analyzed by thin-layer chromatography and gas chromatography. The glycogen-associated fractions did not contain complex lipids but contained unsaturated fatty acids, which had been shown previously to inhibit glucose-6-phosphatase in vitro. Because the concentration of unsaturated fatty acids in both fractions quantitatively accounted for the inhibition of glucose-6 phosphatase observed, and because noninhibitory chromatographed glycogen reconstituted with equivalent amounts of pure unsaturated fatty acids inhibited the enzyme as glycogen did, we conclude that unsaturated fatty acids likely constitute the glycogen-associated compound that inhibits glucose-6 phosphatase activity.
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PMID:Unsaturated fatty acids associated with glycogen may inhibit glucose-6 phosphatase in rat liver. 940 76

The capability of an ethanol extract of Rosmarinus tomentosus to protect rat liver in an experimental model of cirrhosis induced by thioacetamide (TAA) has been evaluated. Four groups of rats were used: Two of them received 300 mg TAA/l in the drinking water for 3 months while the other two, which served as controls, were given water ad libitum. During the same period and for each one of the treatments, one group received a semi-purified (SP) diet and the other one was fed the same diet supplemented with 1% of the dry residue obtained from R. tomentosus ethanol extract (SP+E). There was a significant reduction of TAA toxicity in rats fed the SP+E diet, as assessed by plasma and liver biochemical markers, and by liver histopathology. Plasma total protein concentration was restored, urea concentration and plasma alkaline phosphatase and gamma-glutamyl-transferase activities were reduced. A significant correction of plasma fatty acids concentrations was also evident. Hepatic alkaline phosphatase and gamma-glutamyl-transferase activities were significantly reduced in animals fed SP+E diet and glucose-6-phosphatase activity was significantly enhanced. The results suggest that R. tomentosus ethanol extract administered in the diet affords protection against TAA-induced cirrhosis, preventing most of the histological changes and functionality alterations own to this experimental pathology.
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PMID:Protective effects of Rosmarinus tomentosus ethanol extract on thioacetamide-induced liver cirrhosis in rats. 1636 Sep 39

The present study was designed to investigate the hypoglycemic and hypolipidemic properties of an ethanolic extract of Cichorium intybus (CIE) which is widely used in India as a traditional treatment for diabetes mellitus. Male Sprague-Dawley rats aged 9 weeks (160-200 g) were administered with streptozotocin (STZ, 50mg/kg) intraperitoneally to induce experimental diabetes. The Cichorium intybus whole plant was exhaustively extracted with 80% ethanol, concentrated at 40 degrees C using a rotavapor and freeze dried to get powder. Hypoglycemic effects of CIE were observed in an oral glucose tolerance test (OGTT) in which, a dose of 125 mg of plant extract/kg body weight exhibited the most potent hypoglycemic effect. Moreover, daily administration of CIE (125 mg/kg) for 14 days to diabetic rats attenuated serum glucose by 20%, triglycerides by 91% and total cholesterol by 16%. However, there was no change in serum insulin levels, which ruled out the possibility that CIE induces insulin secretion from pancreatic beta-cells. In addition, hepatic glucose-6-phosphatase activity (Glc-6-Pase) was markedly reduced by CIE when compared to the control group. The reduction in the hepatic Glc-6-Pase activity could decrease hepatic glucose production, which in turn results in lower concentration of blood glucose in CIE-treated diabetic rats. In conclusion, our results support the traditional belief that Cichorium intybus could ameliorate diabetic state.
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PMID:Anti-diabetic effects of Cichorium intybus in streptozotocin-induced diabetic rats. 1719 41

Many anti-diabetic herbal preparations have been recommended in alternative systems of medicine for the treatment of diabetes. No systematic study has been done on the anti-diabetic efficacy of Byesukar, a polyherbal formulation to treat diabetes. The anti-diabetic efficacy of byesukar ethanol extract was evaluated in an animal model of diabetes induced by alloxan. Male Wistar rats were divided in to four groups. Group 1 was normal control group; group 2 and 3 received alloxan. After inducing experimental diabetes group 2 served as diabetic control; group 3 received byesukar (500 mg/kg body weight) orally for 30 consecutive days. Group 4 were normal rats which received byesukar extract alone. The effect of byesukar on glucose level in diabetic rats was studied and the level of glucose metabolizing enzymes (Hexokinase, glucose-6-phosphatase and fructose 1, 6-bisphosphatase) in the liver and kidney were estimated. The effect of byesukar on the serum and tissue lipid profile (Cholesterol, triglycerides, phospholipids and free fatty acids) were also estimated in diabetic rats. Our results indicate that treatment with byesukar resulted in significant reduction of blood glucose, tissue glucose-6-phosphatase and fructose 1, 6- bisphosphatase activity. The decreased tissue hexokinase activity in diabetes state was found to be significantly increased by byesukar treatment. Also the byesukar treated diabetic rats showed a significant decrease in the tissue lipid profile compared to the diabetic rats. In conclusion the decreased blood glucose accompanied with decreased lipid profile and changes in the activities of the glucose metabolizing enzymes shows the antidiabetic effect of byesukar.
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PMID:Phytopharmacological evaluation of Byesukar for hypoglycaemic activity and its effect on lipid profile and hepatic enzymes of glucose metabolism in diabetic rats. 1903 36

This study was conducted to evaluate the antihyperglycemic effect of an extract of Gynostemma pentaphyllum Makino, containing standardized concentrations of gypenosides, in C57BL/KSJ-db/db mice. For 5 weeks, animals were provided a standard AIN-76 diet (normal control) with rosiglitazone (0.005%, wt/wt) or two different doses of G. pentaphyllum ethanol extract (GPE) of the plant leaves (0.0025% and 0.01%, wt/wt). After the experimental period, the blood glucose levels of the high-dose GPE- and rosiglitazone-supplemented groups were significantly lower than that of the control group. The plasma insulin concentrations of the GPE-supplemented mice were significantly elevated compared to the control group. The GPE and rosiglitazone treatments profoundly affected the intraperitoneal insulin tolerance test compared to the control group, but not the intraperitoneal glucose tolerance test. In the evaluation of effects on hepatic glucose metabolism, the ratios of glucokinase/glucose-6-phosphatase activities in the high-dose GPE- and rosiglitazone-supplemented groups were prominently higher than that of the control group. The histology of the pancreatic islets revealed that the insulin-positive beta-cell numbers were higher in the high-dose GPE- and rosiglitazone-supplemented groups than in the control group. These results suggest that the supplementation of high-dose GPE (0.01%) in the diet lowers the blood glucose level by altering the hepatic glucose metabolic enzyme activities.
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PMID:Potential hypoglycemic effect of an ethanol extract of Gynostemma pentaphyllum in C57BL/KsJ-db/db mice. 1905 64


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