Does the time of feeding affect the diurnal rhythms of plasma hormone and glucose concentration and hepatic glycogen content of rainbow trout?

1994 ◽  
Vol 13 (2) ◽  
pp. 133-140 ◽  
Author(s):  
P. K. Reddy ◽  
J. F. Leatherland
Keyword(s):  
Rainbow Trout ◽  
Glucose Concentration ◽  
Glycogen Content ◽  
Diurnal Rhythms ◽  
Hepatic Glycogen ◽  
Plasma Hormone ◽  
Time Of Feeding

scholarly journals Genetic deletion of the circadian clock transcription factor BMAL1 and chronic alcohol consumption differentially alter hepatic glycogen in mice

2018 ◽  
Vol 314 (3) ◽  
pp. G431-G447 ◽  
Author(s):  
Uduak S. Udoh ◽  
Jennifer A. Valcin ◽  
Telisha M. Swain ◽  
Ashley N. Filiano ◽  
Karen L. Gamble ◽  
...  
Keyword(s):  
Alcohol Consumption ◽  
Circadian Clock ◽  
Glycogen Content ◽  
Glycogen Metabolism ◽  
Diurnal Rhythms ◽  
Hepatic Glycogen ◽  
Chronic Alcohol ◽  
Littermate Control ◽  
Chronic Alcohol Consumption ◽  
Control Genotype

Multiple metabolic pathways exhibit time-of-day-dependent rhythms that are controlled by the molecular circadian clock. We have shown that chronic alcohol is capable of altering the molecular clock and diurnal oscillations in several elements of hepatic glycogen metabolism ( 19 , 44 ). Herein, we sought to determine whether genetic disruption of the hepatocyte clock differentially impacts hepatic glycogen content in chronic alcohol-fed mice. Male hepatocyte-specific BMAL1 knockout (HBK) and littermate controls were fed control or alcohol-containing diets for 5 wk to alter hepatic glycogen content. Glycogen displayed a significant diurnal rhythm in livers of control genotype mice fed the control diet. While rhythmic, alcohol significantly altered the diurnal oscillation of glycogen in livers of control genotype mice. The glycogen rhythm was mildly altered in livers of control-fed HBK mice. Importantly, glycogen content was arrhythmic in livers of alcohol-fed HBK mice. Consistent with these changes in hepatic glycogen content, we observed that some glycogen and glucose metabolism genes were differentially altered by chronic alcohol consumption in livers of HBK and littermate control mice. Diurnal rhythms in glycogen synthase (mRNA and protein) were significantly altered by alcohol feeding and clock disruption. Alcohol consumption significantly altered Gck, Glut2, and Ppp1r3g rhythms in livers of control genotype mice, with diurnal rhythms of Pklr, Glut2, Ppp1r3c, and Ppp1r3g further disrupted (dampened or arrhythmic) in livers of HBK mice. Taken together, these findings show that chronic alcohol consumption and hepatocyte clock disruption differentially influence the diurnal rhythm of glycogen and various key glycogen metabolism-related genes in the liver. NEW & NOTEWORTHY We report that circadian clock disruption exacerbates alcohol-mediated alterations in hepatic glycogen. We observed differential responsiveness in diurnal rhythms of glycogen and glycogen metabolism genes and proteins in livers of hepatocyte-specific BMAL1 knockout and littermate control mice fed alcohol. Our findings provide new insights into potential mechanisms by which alcohol alters glycogen, an important energy source for liver and other organs.

scholarly journals O67: PERFUSATE GLUCOSE REFLECTS TISSUE GLYCOGENATION DURING LIVER PERFUSION

2021 ◽  
Vol 108 (Supplement_1) ◽  
Author(s):  
L Matthews ◽  
E Irwin ◽  
P Ezuma ◽  
I Ibrahim ◽  
L Bates ◽  
...  
Keyword(s):  
Glucose Concentration ◽  
Glycogen Content ◽  
Periodic Acid ◽  
Liver Perfusion ◽  
Surrogate Marker ◽  
Liver Graft ◽  
Hepatic Glycogen ◽  
Periodic Acid Schiff ◽  
Synthetic Function ◽  
Insight Into

Abstract Introduction Normothermic machine perfusion (NMP) is a method of organ preservation that aims to replicate the physiological environment, achieved by perfusing the livers with a blood-based perfusate at physiological inflow pressures and temperature. NMP also permits viability assessment through evaluation of the perfusate flow rates through the portal vein and hepatic artery. In addition to this, biochemical assessment and perfusate gas analysis can be performed to provide insights into the metabolic activity of the liver. Method Discarded human liver grafts (n=6), were perfused for 24 hours. Core biopsies and perfusate samples were taken from each liver at 5 distinct time intervals over 24 hours. Core biopsies were fixed and stained with periodic acid-Schiff and analysed with Leica software to provide a quantitative estimate of the hepatocellular glycogen content. Result Hepatic glycogen concentration rose during the first hour, followed by a steady decline thereafter until the end of perfusion. Contrary to our initial hypothesis that glucose concentration within the circuit would show an inverse relationship to glycogen stores in the liver cells, we found that glucose concentration closely followed the same trend. Conclusion Change in hepatocyte glycogen content provides an important insight into the synthetic function of a liver destined for transplant. Our research suggests that glucose concentration can be used as a surrogate marker for the synthetic function of a liver on NMP and provides valuable information on the glycogen-synthesising capability of the hepatocytes. In future, this could potentially aid the decision-making process with regards to liver graft transplant viability. Take-home message Perfusate glucose concentration could provide an insight into the viability of liver transplants

ÉTUDE IN VITRO DU MÉTABOLISME DES HYDRATES DE CARBONE DANS LE LEUCOCYTE CIRCULANT DU COBAYE TRAITÉ À LA CORTISONE

1966 ◽  
Vol 51 (2) ◽  
pp. 193-202
Author(s):  
J. A. Antonioli ◽  
A. Vannotti
Keyword(s):  
Glucose Concentration ◽  
Intramuscular Injection ◽  
Acute Inflammation ◽  
Glycogen Content ◽  
Glycogen Synthesis ◽  
Lactate Production ◽  
Glucose Consumption ◽  
List Type ◽  
Hydrates De Carbone

ABSTRACT 1. The metabolism of suspensions of circulating leucocytes has been studied after intramuscular injection of a dose of 50 mg/kg of a corticosteroid (cortisone acetate). The suspensions were incubated under aerobic conditions in the presence of a glucose concentration of 5.6 mm. Glucose consumption, lactate production, and variations in intracellular glycogen concentration were measured. After the administration of the corticosteroid, the anabolic processes of granulocyte metabolism were reversibly stimulated. Glucose consumption and lactate production increased 12 hours after the injection, but tended to normalize after 24 hours. The glycogen content of the granulocytes was enhanced, and glycogen synthesis during the course of the incubation was greatly stimulated. The action of the administered corticosteroid is more prolonged in females than in males. The injection of the corticosteroid caused metabolic modifications which resemble in their modulations and in their chronological development those found in circulating granulocytes of guinea-pigs suffering from sterile peritonitis. These results suggest, therefore, that, in the case of acute inflammation, the glucocorticosteroids may play an important role in the regulation of the metabolism of the blood leucocytes.

Contribution of net hepatic glycogenolysis to glucose production during the early postprandial period

1996 ◽  
Vol 270 (1) ◽  
pp. E186-E191 ◽  
Author(s):  
K. F. Petersen ◽  
T. Price ◽  
G. W. Cline ◽  
D. L. Rothman ◽  
G. I. Shulman
Keyword(s):  
Magnetic Resonance ◽  
Glycogen Content ◽  
Hepatic Glucose Production ◽  
Liver Volume ◽  
Glucose Production ◽  
Liver Glycogen ◽  
Whole Body ◽  
Hepatic Glycogen ◽  
Resonance Spectroscopy ◽  
13C Nuclear Magnetic Resonance

Relative contributions of net hepatic glycogenolysis and gluconeogenesis to glucose production during the first 12 h of a fast were studied in 13 healthy volunteers by noninvasively measuring hepatic glycogen content using 13C nuclear magnetic resonance spectroscopy. Rates of net hepatic glycogenolysis were calculated by multiplying the change in liver glycogen content with liver volume determined by magnetic resonance imaging. Rates of gluconeogenesis were calculated as the difference between rates of glucose production determined with an infusion of [6,6-2H]-glucose and net hepatic glycogenolysis. At 6 P.M. a liquid mixed meal (1,000 kcal; 60% as glucose) was given, to which [2-2H]glucose was added to trace glucose absorption. Hepatic glycogen content was measured between 11 P.M. and 1 A.M. and between 3 and 6 A.M. At 11 P.M. the concentration was 470 mM and it decreased linearly during the night. The mean liver volume was 1.47 +/- 0.06 liters. Net hepatic glycogenolysis (5.8 +/- 0.8 mumol.kg body wt-1.min-1) accounted for, on average, 45 +/- 6% and gluconeogenesis for 55 +/- 6% of the rate of whole body glucose production (12.6 +/- 0.6 mumol.kg body wt-1.min-1). In conclusion, this study shows that, even early in the phase of the postabsorptive period when liver glycogen stores are maximal, gluconeogenesis contributes approximately 50% to hepatic glucose production.

Effect of perfusate glucose concentration on rat lung glycolysis.

1979 ◽  
Vol 236 (3) ◽  
pp. E229 ◽  
Author(s):  
J S Kerr ◽  
N J Baker ◽  
D J Bassett ◽  
A B Fisher
Keyword(s):  
Glucose Concentration ◽  
Glucose Utilization ◽  
Glycogen Content ◽  
Lactate Production ◽  
Bicarbonate Buffer ◽  
Exogenous Glucose ◽  
Low Glucose ◽  
The Difference ◽  
Endogenous Substrates ◽  
The Relationship

We investigated the relationship between perfusate concentration of glucose and its utilization and lactate production derived from exogenous glucose and from metabolism of endogenous substrates. Isolated rat lungs were ventilated with 5% CO2 in air and perfused for 100 min with Krebs-Ringer bicarbonate buffer containing 3% bovine serum albumin, 10(-2) U/ml insulin, [U-14C]glucose and [5-3H]glucose. Glucose utilization, total lactate production, [14C]lactate production, and 3H2O production were measured. The apparent Km and Vmax for glucose utilization were 3.4 mM and 72.5 mumol/g dry wt per h, respectively. Lactate production from endogenous substrates, calculated as the difference between total and [14C]lactate, was 37.6 +/- 2.2 mumol/g dry wt (n = 36); it was unaffected by perfusate glucose concentration and by omission of insulin, but increased threefold with anoxia. Lactate production from 1.5 mM glucose was significantly less (P less than 0.02) with insulin omitted. Glycogen content was unchanged during perfusion without glucose. These results suggest that: 1) protein catabolism contributes to lung lactate production; 2) glucose utilization by lung is not maximal at resting physiological glucose concentrations; and 3) insulin is required at low glucose concentrations for maximal glycolytic rates.

scholarly journals Adrenergic stimulation of substrate utilization by cardiac myocytes isolated from rainbow trout

1991 ◽  
Vol 159 (1) ◽  
pp. 185-202 ◽  
Author(s):  
C. L. Milligan
Keyword(s):  
Rainbow Trout ◽  
Lactate Dehydrogenase ◽  
Cardiac Myocytes ◽  
Trypan Blue ◽  
Glycogen Content ◽  
Substrate Utilization ◽  
Co2 Production ◽  
Adrenergic Agonists ◽  
Adrenergic Stimulation ◽  
Stimulation Of

A method is described for the isolation of calcium-tolerant myocytes from adult rainbow trout. Isolated myocytes remain viable for at least 4 h in suspension as indicated by (1) maintenance of ATP, phosphocreatine (PCr) and glycogen levels; (2) maintenance of the integrity of cell membranes, shown by low rates of leakage of lactate dehydrogenase (LDH) to the medium and exclusion of Trypan Blue; (3) the ability to metabolize substrates; and (4) sensitivity to adrenergic agonists. CO2 production from both glucose and lactate was sensitive to adrenergic stimulation, with the following order of potency: isoproterenol greater than noradrenaline much greater than adrenaline greater than phenylephrine, which indicates the presence of beta 1-adrenoceptors. Myocytes isolated from trout acclimated to 20 degrees C in the summer were more sensitive to beta-adrenergic stimulation than myocytes isolated from trout acclimated to 9 degrees C in either summer or winter. In the absence of exogenous fuel, there was a net reduction in myocyte glycogen content and glycogenolysis was further stimulated by 10(−7) mmol l-1 noradrenaline. However, in the presence of exogenous fuel (either 5 mmol l-1 lactate or 5 mmol l-1 glucose), glycogen was ‘spared’ and noradrenaline-stimulated glycogenolysis was apparently inhibited.

Plasma glucose concentration determines direct versus indirect liver glycogen synthesis

1986 ◽  
Vol 251 (5) ◽  
pp. E584-E590 ◽  
Author(s):  
C. H. Lang ◽  
G. J. Bagby ◽  
H. L. Blakesley ◽  
J. L. Johnson ◽  
J. J. Spitzer
Keyword(s):  
Plasma Glucose ◽  
Glucose Concentration ◽  
Infusion Rate ◽  
Glycogen Synthesis ◽  
Liver Glycogen ◽  
Glucose Infusion ◽  
Glucose Infusion Rate ◽  
Hepatic Glycogen ◽  
Glucose Load ◽  
Indirect Pathway

In the present study hepatic glycogenesis by the direct versus indirect pathway was determined as a function of the glucose infusion rate. Glycogen synthesis was examined in catheterized conscious rats that had been fasted 48 h before receiving a 3-h infusion (iv) of glucose. Glucose, containing tracer quantities of [U-14C]- and [6-3H]glucose, was infused at rates ranging from 0 to 230 mumol X min-1 X kg-1. Plasma concentrations of glucose, lactate, and insulin were positively correlated with the glucose infusion rate. Despite large changes in plasma glucose, lactate, and insulin concentrations, the rate of hepatic glycogen deposition (0.46 +/- 0.03 mumol X min-1 X g-1) did not vary significantly between glucose infusion rates of 20 and 230 mumol X min-1 X kg-1. However, the percent contribution of the direct pathway to glycogen repletion gradually increased from 13 +/- 2 to 74 +/- 4% in the lowest to the highest glucose infusion rates, with prevailing plasma glucose concentrations from 9.4 +/- 0.5 to 21.5 +/- 2.1 mM. Endogenous glucose production was depressed (by up to 40%), but not abolished by the glucose infusions. Only a small fraction (7-14%) of the infused glucose load was incorporated into liver glycogen via the direct pathway irrespective of the glucose infusion rate. Our data indicate that the relative contribution of the direct and indirect pathways of hepatic glycogen synthesis are dependent on the glucose load or plasma glucose concentration and emphasize the predominance of the indirect pathway of glycogenesis at plasma glucose concentrations normally observed after feeding.

CNS stimulation does not affect hepatic venous glucose concentration in severely diabetic rats

1991 ◽  
Vol 260 (3) ◽  
pp. E440-E446
Author(s):  
H. Miura ◽  
A. Iguchi ◽  
K. Uemura ◽  
A. Yatomi ◽  
T. Tamagawa ◽  
...  
Keyword(s):  
Plasma Glucose ◽  
Glucose Concentration ◽  
Diabetic Rats ◽  
Hepatic Glycogen ◽  
Severe Diabetes ◽  
The Central Nervous System ◽  
Cns Stimulation ◽  
Pentobarbital Sodium Anesthesia ◽  
Glucose Output ◽  
Venous Plasma

To assess the role of the central nervous system (CNS) in carbohydrate metabolism in diabetes, neostigmine was injected into the third cerebral ventricle in fed rats with streptozotocin (STZ; 80 mg/kg)-induced diabetes under pentobarbital sodium anesthesia. Changes in hepatic venous plasma glucose concentrations were monitored. Neostigmine injection caused no significant changes in the hepatic venous plasma glucose concentration in untreated diabetic rats, whereas the glucose level increased significantly in insulin-treated diabetic rats similarly to the changes in normal control animals. In diabetic rats, the plasma levels of glucagon, epinephrine, and norepinephrine were increased significantly by neostigmine. After various doses (35-80 mg/kg) were given to rats, it was found that the higher the STZ dose, the lower was the hepatic glycogen content and the smaller was the glycemic response to neostigmine. Our results indicate that, in severe diabetes, CNS stimulation with neostigmine fails to increase hepatic glucose output, because glycogen stores are nearly exhausted and gluconeogenesis is already maximal.

Effect of maternal canine starvation on fetal and neonatal liver metabolism

1981 ◽  
Vol 240 (2) ◽  
pp. E88-E94
Author(s):  
E. L. Miettinen
Keyword(s):  
Fatty Acid ◽  
Free Fatty Acid ◽  
Glucose Concentration ◽  
Acid Oxidation ◽  
Hepatic Glycogen ◽  
Uridine Diphosphate ◽  
Nadh Ratio ◽  
Free Fatty Acid Oxidation ◽  
Diphosphate Glucose ◽  
Neonatal Liver

Heptic glycolytic and gluconeogenic intermediates from fasted newborns of five control and five 3-day starved canine mothers (MCS) were studied at 0, 3, 6, 9, and 24 h of age. MCS did not affect fetal hepatic glycogen concentration; however, a significant increase in uridine diphosphate glucose (UDPG) (0.186 vs. 0.106 mumol/g), fructose 6-phosphate (0.084 vs. 0.034), pyruvate (0.321 vs. 0.126), and citrate (0.190 vs. 0.140) concentrations occurred. At 3 h, the intrahepatic glucose concentration among the MCS newborns declined (3.09 vs. 6.34) and remained lower than the controls for up to 9 h. UDPG concentration, however, remained elevated throughout the 24 h. In addition intrahepatic pyruvate was significantly elevated in the MCS group. Elevated phosphoenolpyruvate concentrations were observed between 3 and 6 h. Malate levels were lower than controls between 6 and 9 h and alpha-ketoglutarate was significantly higher between 6 and 24 h. Calculated cytoplasmic NAD/NADH ratio was elevated throughout the 24 h. Hepatic triglycerides were higher than controls up to 9 h. A decline in hepatic triglycerides was observed between 9 and 24 h. The results suggest increased glycolysis and suppressed gluconeogenesis in the MCS puppies, probably because of increased triglyceride synthesis and decreased free fatty acid oxidation resulting in a lack of cytoplasmic NADH.

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