scholarly journals Effects of chronic hyperinsulinaemia on hepatic enzymes involved in lipogenesis and carbohydrate metabolism in the young rat

1978 ◽  
Vol 172 (2) ◽  
pp. 327-331 ◽  
Author(s):  
K L McCormick ◽  
J A Widness ◽  
J B Susa ◽  
R Schwartz
Keyword(s):  
Pyruvate Kinase ◽  
Malic Enzyme ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Liver Weight ◽  
Hepatic Enzymes ◽  
Lower Blood Glucose ◽  
Lower Blood ◽  
Cleavage Enzyme ◽  
Young Rat ◽  
Blood Glucose Concentrations

Chronic (6 days) hyperinsulinaemia in young rats produced lower blood glucose concentrations and augmented body- and liver-weight gain. The insulin-treated rats had increased hepatic activities of citrate-cleavage enzyme, ‘malic’ enzyme and high-substrate (6.6 mM-phosphoenolpyruvate) pyruvate kinase, and decreased glucose 6-phosphatase. There were no changes in activities of phosphoenolpyruvate carboxykinase, phosphofructokinase, low-substrate (1.3 mM-phosphoenolpyruvate) pyruvate kinase, glucokinase and hexokinase.

scholarly journals Noodles Made from High Amylose Wheat Flour Attenuate Postprandial Glycaemia in Healthy Adults

Nutrients ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2171
Author(s):  
Kim Ang ◽  
Carla Bourgy ◽  
Haelee Fenton ◽  
Ahmed Regina ◽  
Marcus Newberry ◽  
...  
Keyword(s):  
Young Adults ◽  
Blood Glucose ◽  
Wheat Flour ◽  
Glucose Concentration ◽  
Blood Glucose Concentration ◽  
Lower Blood Glucose ◽  
Postprandial Glycaemia ◽  
Lower Blood ◽  
High Amylose ◽  
Blood Glucose Concentrations

Previous research has not considered the effect of high amylose wheat noodles on postprandial glycaemia. The aim of the study is to investigate the effect of consumption of high amylose noodles on postprandial glycaemia over 2-h periods by monitoring changes in blood glucose concentration and calculating the total area under the blood glucose concentration curve. Twelve healthy young adults were recruited to a repeated measure randomised, single-blinded crossover trial to compare the effect of consuming noodles (180 g) containing 15%, 20% and 45% amylose on postprandial glycaemia. Fasting blood glucose concentrations were taken via finger-prick blood samples. Postprandial blood glucose concentrations were taken at 15, 30, 45, 60, 90 and 120 min. Subjects consuming high amylose noodles made with flour containing 45% amylose had significantly lower blood glucose concentration at 15, 30 and 45 min (5.5 ± 0.11, 6.1 ± 0.11 and 5.6 ± 0.11 mmol/L; p = 0.01) compared to subjects consuming low amylose noodles with 15% amylose (5.8 ± 0.12, 6.6 ± 0.12 and 5.9 ± 0.12 mmol/L). The total area under the blood glucose concentration curve after consumption of high amylose noodles with 45% amylose was 640.4 ± 9.49 mmol/L/min, 3.4% lower than consumption of low amylose noodles with 15% amylose (662.9 ± 9.49 mmol/L/min), p = 0.021. Noodles made from high amylose wheat flour attenuate postprandial glycaemia in healthy young adults, as characterised by the significantly lower blood glucose concentration and a 3.4% reduction in glycaemic response.

The Effects of Catecholamines, Glucagon, and Diet on Enzyme Activities in Brown Fat and Liver of the Rat

1974 ◽  
Vol 52 (9) ◽  
pp. 739-743 ◽  
Author(s):  
Peter Hahn ◽  
Lorne T. Kirby
Keyword(s):  
Body Weight ◽  
Fatty Acid ◽  
Malic Enzyme ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Fatty Acid Synthetase ◽  
High Carbohydrate Diet ◽  
Brown Fat ◽  
Carbohydrate Diet ◽  
High Carbohydrate ◽  
Cleavage Enzyme

The effects of a high carbohydrate diet fed to young rats for 24–48 h on phosphoenolpyruvate carboxykinase, malic enzyme, citrate-cleavage enzyme, and fatty acid synthetase could be overcome by injecting the animals with glucagon (1 mg/100 g body weight) or norepinephrine (20 μg/100 g body weight) four times a day. The same effect was achieved with 50 mg ephedrine added to the 24 h diet. The catecholamines were more effective in brown fat, whereas glucagon seemed somewhat more effective in the liver.

scholarly journals Activity of selected gluconeogenic and lipogenic enzymes in bovine rumen mucosa, liver and adipose tissue

1969 ◽  
Vol 114 (1) ◽  
pp. 83-88 ◽  
Author(s):  
Jerry W. Young ◽  
Sylvia L. Thorp ◽  
Helen Z. De Lumen
Keyword(s):  
Enzyme Activity ◽  
Adipose Tissue ◽  
Dehydrogenase Activity ◽  
Malic Enzyme ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Lipogenic Enzymes ◽  
Adipose Tissues ◽  
Cleavage Enzyme ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Enzyme Patterns

The activities of phosphoenolpyruvate carboxykinase, ‘malic enzyme’, citrate-cleavage enzyme and glucose 6-phosphate dehydrogenase were assayed in homogenates of rumen mucosa, liver and adipose tissue of cattle. Rumen mucosa cytoplasm contained activities of ‘malic enzyme’ approximately sevenfold those of phosphoenolpyruvate carboxykinase, suggesting that the conversion of propionate into lactate by rumen mucosa involves ‘malic enzyme’. Neither starvation for 8 days nor feeding with a concentrate diet for at least 3 months before slaughter produced enzyme patterns in the tissues different from those in cattle given only hay, except that the all-concentrate diet caused increased activities of glucose 6-phosphate dehydrogenase and ‘malic enzyme’ in adipose tissues. Rumen mucosa, liver and adipose tissue contained phosphoenolpyruvate carboxykinase activity. ‘Malic enzyme’ was absent in liver. Citrate-cleavage enzyme activity was present in liver and adipose tissue but was quite low in rumen mucosa. Liver contained much less glucose 6-phosphate dehydrogenase activity than rumen mucosa or adipose tissue.

Glucose lowering effects of inhaled insulin in healthy cats

2008 ◽  
Vol 10 (5) ◽  
pp. 519-522 ◽  
Author(s):  
Amy E. DeClue ◽  
Elizabeth F. Leverenz ◽  
Charles E. Wiedmeyer ◽  
Margaret E. Bryan ◽  
Carol R. Reinero
Keyword(s):  
Blood Glucose ◽  
Severe Hypoglycemia ◽  
Regular Insulin ◽  
Lower Blood Glucose ◽  
Glucose Lowering ◽  
Inhaled Insulin ◽  
Lower Blood ◽  
Adult Cats ◽  
Blood Glucose Concentrations ◽  
Mean Blood Glucose

Inhaled medications have proven effective and well tolerated in cats, and inhaled insulin has been used successfully for the management of diabetes mellitus in humans. Thus, we hypothesize that delivery of aerosolized regular insulin can lower blood glucose in healthy cats. Five adult cats were administered aerosolized 0.9% saline (IS), regular insulin intravenously (IV) 0.5 U/kg, and aerosolized regular insulin 15 U/kg (I15) and 25 U/kg (I25) and blood glucose was evaluated. Mean blood glucose was significantly lower at 15, 30 and 45 min in the I25 and IV groups compared to baseline. Similarly, the IV and I25 groups had a significantly greater maximal percent change in blood glucose than the IS group. Significantly more cats developed severe hypoglycemia (<50 mg/dl; 2.7 mmol/l) in the IV and I25 groups than in the IS group. Results of this study demonstrate that aerosolized insulin can effectively lower blood glucose concentrations in healthy cats.

Hepatic mechanisms of the Walnut antidiabetic effect in mice

2010 ◽  
Vol 5 (3) ◽  
pp. 304-309 ◽  
Author(s):  
Hanieh Kamyab ◽  
Shohreh Hejrati ◽  
Mahnaz Khanavi ◽  
Farshad Malihi ◽  
Azadeh Mohammadirad ◽  
...  
Keyword(s):  
Blood Glucose ◽  
Glycogen Phosphorylase ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Experimental Diabetes ◽  
Juglans Regia ◽  
Lower Blood Glucose ◽  
Hepatic Glucose Metabolism ◽  
Pancreatic Insulin ◽  
Lower Blood ◽  
Hepatic Glucose

AbstractThe present study was designed to explore the mechanism of action of walnut (the seed of Juglans regia) leaf and ridge on hepatic glucose metabolism in diabetic mice. Experimental diabetes was induced by intravenous administration of streptozotocin (60 mg/kg)and confirmed with an increase of blood glucose, 90–100% of the control, 72 hours later. Isolated extracts from walnut leaf and ridges were administered in a single effective dose of 400 mg/kg orally. Firstly, blood glucose was determined every 1 hour until 5 hours post administration of extracts. In the second experiment, the liver was surgically removed, 2 hours post treatment of diabetic animals with extracts, homogenized and used for measurement of key enzymes of glycogenolysis (glycogen phosphorylase, GP) and gluconeogenesis (phosphoenolpyruvate carboxykinase, PEPCK). Treatment by both leaf and ridge extracts decreased blood glucose and liver PEPCK activity and increased blood insulin and liver GP activity. It is concluded that walnut is able to lower blood glucose through inhibition of hepatic gluconeogenesis and secretion of pancreatic insulin.

scholarly journals Presence of Adult Companion Goats Favors the Rumen Microbial and Functional Development in Artificially Reared Kids

2021 ◽  
Vol 8 ◽  
Author(s):  
Juan Manuel Palma-Hidalgo ◽  
David R. Yáñez-Ruiz ◽  
Elisabeth Jiménez ◽  
A. Ignacio Martín-García ◽  
Alejandro Belanche
Keyword(s):  
Bacterial Community ◽  
The Body ◽  
Lower Blood Glucose ◽  
Rumen Ph ◽  
Functional Development ◽  
Lower Blood ◽  
Microbial Development ◽  
Proteolytic Activities ◽  
Animal Growth ◽  
Blood Glucose Concentrations

Newborn dairy ruminants are usually separated from their dams after birth and fed on milk replacer. This lack of contact with adult animals may hinder the rumen microbiological and physiological development. This study evaluates the effects of rearing newborn goat kids in contact with adult companions on the rumen development. Thirty-two newborn goat kids were randomly allocated to two experimental groups which were reared either in the absence (CTL) or in the presence of non-lactating adult goats (CMP) and weaned at 7 weeks of age. Blood and rumen samples were taken at 5, 7, and 9 weeks of age to evaluate blood metabolites and rumen microbial fermentation. Next-generation sequencing was carried out on rumen samples collected at 7 weeks of age. Results showed that CTL kids lacked rumen protozoa, whereas CMP kids had an abundant and complex protozoal community as well as higher methanogen abundance which positively correlated with the body weight and blood β-hydroxybutyrate as indicators of the physiological development. CMP kids also had a more diverse bacterial community (+132 ASVs) and a different structure of the bacterial and methanogen communities than CTL kids. The core rumen bacterial community in CMP animals had 53 more ASVs than that of CTL animals. Furthermore, the number of ASVs shared with the adult companions was over 4-fold higher in CMP kids than in CTL kids. Greater levels of early rumen colonizers Proteobacteria and Spirochaetes were found in CTL kids, while CMP kids had higher levels of Bacteroidetes and other less abundant taxa (Veillonellaceae, Cyanobacteria, and Selenomonas). These findings suggest that the presence of adult companions facilitated the rumen microbial development prior to weaning. This accelerated microbial development had no effect on the animal growth, but CMP animals presented higher rumen pH and butyrate (+45%) and ammonia concentrations than CTL kids, suggesting higher fibrolytic and proteolytic activities. CMP kids also had higher blood β-hydroxybutyrate (+79%) and lower blood glucose concentrations (-23%) at weaning, indicating an earlier metabolic development which could favor the transition from pre-ruminant to ruminant after the weaning process. Further research is needed to determine the effects of this intervention in more challenging farm conditions.

scholarly journals Properties of pyruvate kinase and phosphoenolpyruvate carboxykinase in relation to the direction and regulation of phosphoenolpyruvate metabolism in muscles of the frog and marine invertebrates

1978 ◽  
Vol 174 (3) ◽  
pp. 979-987 ◽  
Author(s):  
Victor A. Zammit ◽  
Eric A. Newsholme
Keyword(s):  
Pyruvate Kinase ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Marine Invertebrates ◽  
Adductor Muscle ◽  
Sea Anemone ◽  
Anaerobic Conditions ◽  
Fructose Bisphosphate ◽  
Low Concentrations ◽  
Optimum Ph ◽  
Hill Coefficients

1. The properties of pyruvate kinase and, if present, phosphoenolpyruvate carboxykinase from the muscles of the sea anemone, scallop, oyster, crab, lobster and frog were investigated. 2. In general, the properties of pyruvate kinase from all muscles were similar, except for those of the enzyme from the oyster (adductor muscle); the pH optima were between 7.1 and 7.4, whereas that for oyster was 8.2; fructose bisphosphate lowered the optimum pH of the oyster enzyme from 8.2 to 7.1, but it had no effect on the enzymes from other muscles. Hill coefficients for the effect of the concentration of phosphoenolpyruvate were close to unity in the absence of added alanine for the enzymes from all muscles except oyster adductor muscle; it was 1.5 for this enzyme. Alanine inhibited the enzyme from all muscles except the frog; this inhibition was relieved by fructose bisphosphate. Low concentrations of alanine were very effective with the enzyme from the oyster (50% inhibition was observed at 0.4mm). Fructose bisphosphate activated the enzyme from all muscles, but extremely low concentrations were effective with the oyster enzyme (0.13μm produced 50% activation). 3. In general, the properties of phosphoenolpyruvate carboxykinase from the sea anemone and oyster muscles are similar: the Km values for phosphoenolpyruvate are low (0.10 and 0.13mm); the enzymes require Mn2+ in addition to Mg2+ for activity; and ITP inhibits the enzymes and the inhibition is relieved by alanine. These latter compounds had no effect on enzymes from other muscles. 4. It is suggested that changes in concentrations of fructose bisphosphate, alanine and ITP produce a coordinated mechanism of control of the activities of pyruvate kinase and phosphoenolpyruvate carboxykinase in the sea anemone and oyster muscles, which ensures that phosphoenolpyruvate is converted into oxaloacetate and then into succinate in these muscles under anaerobic conditions. 5. It is suggested that in the muscles of the crab, lobster and frog, phosphoenolpyruvate carboxykinase catalyses the conversion of oxaloacetate into phosphoenolpyruvate. This may be part of a pathway for the oxidation of some amino acids in these muscles.

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