scholarly journals Glucose metabolism in perfused skeletal muscle. Effects of starvation, diabetes, fatty acids, acetoacetate, insulin and exercise on glucose uptake and disposition

1976 ◽  
Vol 158 (2) ◽  
pp. 191-202 ◽  
Author(s):  
M Berger ◽  
S A Hagg ◽  
M N Goodman ◽  
N B Ruderman
Keyword(s):  
Skeletal Muscle ◽  
Fatty Acids ◽  
Glucose Metabolism ◽  
Glucose Uptake ◽  
Ketone Bodies ◽  
Diabetic Rats ◽  
Lactate Oxidation ◽  
Fed State ◽  
Lactate Release ◽  
Sciatic Nerve Stimulation

1. The regulation of glucose uptake and disposition in skeletal muscle was studied in the isolated perfused rat hindquarter. 2. Insulin and exercise, induced by sciatic-nerve stimulation, enhanced glucose uptake about tenfold in fed and starved rats, but were without effect in rats with diabetic ketoacidosis. 3. At rest, the oxidation of lactate (0.44 mumol/min per 30 g muscle in fed rats) was decreased by 75% in both starved and diabetic rats, whereas the release of alanine and lactate (0.41 and 1.35 mumol/min per 30 g respectively in the fed state) was increased. Glycolysis, defined as the sum of lactate+alanine release and lactate oxidation, was not decreased in either starvation or diabetes. 4. In all groups, exercise tripled O2 consumption (from approximately 8 to approximately 25 mumol/min per 30 g of muscle) and increased the release and oxidation of lactate five- to ten-fold. The differences in lactate release between fed, starved and diabetic rats observed at rest were no longer apparent; however, lactate oxidation was still several times greater in the fed group. 5. Perfusion of the hindquarter of a fed rat with palmitate, octanoate or acetoacetate did not alter glucose uptake or lactate release in either resting or exercising muslce; however, lactate oxidation was significantly inhibited by acetoacetate, which also increased the intracellular concentration of acetyl-CoA. 6. The data suggest that neither that neither glycolysis nor the capacity for glucose transport are inhbitied in the perfused hindquarter during starvation or perfusion with fatty acids or ketone bodies. On the other hand, lactate oxidation is inhibited, suggesting diminished activity of pyruvate dehydrogenase. 7. Differences in the regulation of glucose metabolism in heart and skeletal muscle and the role of the glucose/fatty acid cycle in each tissue are discussed.

Net substrates balance across hindlimb in conscious rabbit during late pregnancy

1986 ◽  
Vol 251 (1) ◽  
pp. E42-E47 ◽  
Author(s):  
M. Bouisset ◽  
M. C. Pere ◽  
M. Gilbert
Keyword(s):  
Skeletal Muscle ◽  
Fatty Acids ◽  
Free Fatty Acids ◽  
Glucose Uptake ◽  
Ketone Bodies ◽  
Late Pregnancy ◽  
Gravid Uterus ◽  
Minor Importance ◽  
Insulin Effect ◽  
Increase Glucose Uptake

The present work performed in rabbits was designed to investigate whether changes in skeletal muscle metabolism could contribute to glucose homeostasis during late pregnancy a time at which there is a large glucose demand of the gravid uterus. We therefore studied the net substrate balance of glucose, lactate, free fatty acids, and ketone bodies across the hindlimb of pregnant animals (days 24 and 30) and virgin animals. Our data show that on day 24 the basal rate of glucose uptake is similar to that observed in virgin rabbits, but it decreases by approximately 60% on day 30 despite comparable levels of blood glucose and plasma insulin at both gestational ages. A moderate hyperglycemia (20% above basal level) and hyperinsulinemia (2- to 3-fold above basal level) sustained for 80 min failed to increase glucose uptake except in virgin animals. Estimates of the contribution of substrates to oxidative metabolism indicate that free fatty acids could represent the major fuel in all groups, whereas glucose would be of minor importance especially at term. It is concluded that in pregnancy a) under normoglycemia there is a reduced insulin effect on glucose uptake and b) under moderate hyperglycemia and hyperinsulinemia the insulin resistance results from an impaired stimulation of glucose uptake. Sparing glucose from the skeletal muscle, the mother can direct more glucose toward the uterus without marked increase in her production rate.

scholarly journals Glucose metabolism in perfused skeletal muscle. Interaction of insulin and exercise on glucose uptake

1975 ◽  
Vol 146 (1) ◽  
pp. 231-238 ◽  
Author(s):  
M Berger ◽  
S Hagg ◽  
N B Ruderman
Keyword(s):  
Skeletal Muscle ◽  
Glucose Uptake ◽  
Diabetic Ketoacidosis ◽  
Isometric Exercise ◽  
Diabetic Rats ◽  
Intracellular Concentration ◽  
Increase Glucose Uptake ◽  
Exercise Induced ◽  
Sciatic Nerve Stimulation ◽  
Resting Muscle

1. The interaction of insulin and isometric exercise on glucose uptake by skeletal muscle was studied in the isolated perfused rat hindquarter. 2. Insulin, 10 m-i.u./ml, added to the perfusate, increased glucose uptake more than 10-fold, from 0.3-0.5 to 5.2-5.4 μmol/min per 30g of muscle in hindquarters of fed and 48h-starved rats respectively. In contrast, it did not stimulate glucose uptake in hindquarters from rats in diabetic ketoacidosis. 3. In the absence of added insulin, isometric exercise, induced by sciatic-nerve stimulation, increased glucose uptake to 4 and 3.4 μmol/min per 30g of muscle in fed and starved rats respectively. It had a similar effect in rats with moderately severe diabetes, but it did not increase glucose uptake in rats with diabetic ketoacidosis or in hindquarters of fed rats that had been “washed out” with an insulin-free perfusate. Insulin, at concentrations which did not stimulate glucose uptake in resting muscle, restored the stimulatory effect of exercise in these situations. 4. The stimulation of glucose uptake by exercise was independent of blood flow and the degree of tissue hypoxia; also it could not be reproduced by perfusing resting muscle with a medium previously used in an exercise experiment. 5. At rest glucose was not detectable in muscle cell water of fed and starved rats even when perfused with insulin. In the presence of insulin, a small accumulation of glucose, 0.25 mM, was noted in the muscle of ketoacidotic diabetic rats, suggesting inhibition of glucose phosphorylation, as well as of transport. 6. During exercise, the calculated intracellular concentration of glucose in the contracting muscle increased to 1.1-1.6mM in the fed, starved and moderately diabetic groups. Insulin significantly increased the already high rates of glucose uptake by the hindquarters of these animals but it did not alter the elevated intracellular concentration of glucose. 7. In severely diabetic rats, exercise did not cause glucose to accumulate in the cell in the absence of insulin. In the presence of insulin, it increased glucose uptake to 6.1 μmol/min per 30g of muscle and intracellular glucose to 0.72 mM. 8. The data indicate that the stimulatory effect of exercise on glucose uptake requires the presence of insulin. They suggest that in the absence of insulin, glucose uptake is not enhanced by exercise owing to inhibition of glucose transport into the cell.

scholarly journals Glucose metabolism in perfused skeletal muscle. Demonstration of insulin resistance in the obese Zucker rat

1979 ◽  
Vol 178 (3) ◽  
pp. 733-741 ◽  
Author(s):  
F W Kemmer ◽  
M Berger ◽  
L Herberg ◽  
F A Gries ◽  
A Wirdeier ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Glucose Metabolism ◽  
Glucose Uptake ◽  
Glucose Transport ◽  
Muscle Cell ◽  
Inhibitory Effect ◽  
Zucker Rats ◽  
Control Group ◽  
Lactate Oxidation ◽  
Obese Zucker Rats

1. The effect of insulin (0.5, 10 and 50 munits/ml of perfusate) on glucose uptake and disposal in skeletal muscle was studied in the isolated perfused hindquarter of obese (fa/fa) and lean (Fa/Fa) Zucker rats and Osborne-Mendel rats. 2. A concentration of 0.5 munit of insulin/ml induced a significant increase in glucose uptake (approx. 2.5 mumol/min per 30 g of muscle) in lean Zucker rats and in Osborne-Mendel rats, and 10 munits of insulin/ml caused a further increase to approx. 6 mumol/min per 30 g of muscle; but 50 munits of insulin/ml had no additional stimulatory effect. In contrast, in obese Zucker rats only 10 and 50 munits of insulin/ml had a stimulatory effect on glucose uptake, the magnitude of which was decreased by 50-70% when compared with either lean control group. Since under no experimental condition tested was an accumulation of free glucose in muscle-cell water observed, the data suggest an impairment of insulin-stimulated glucose transport across the muscle-cell membrane in obese Zucker rats. 3. The intracellular disposal of glucose in skeletal muscle of obese Zucker rats was also insulin-insensitive: even at insulin concentrations that clearly stimulated glucose uptake, no effect of insulin on lactate oxidation (nor an inhibitory effect on alanine release) was observed; [14C]glucose incorporation into skeletal-muscle lipids was stimulated by 50 munits of insulin/ml, but the rate was still only 10% of that observed in lean Zucker rats. 4. The data indicate that the skeletal muscle of obese Zucker rats is insulin-resistant with respect to both glucose-transport mechanisms and intracellular pathways of glucose metabolism, such as lactate oxidation. The excessive degree of insulin-insensitivity in skeletal muscle of obese Zucker rats may represent a causal factor in the development of the glucose intolerance in this species.

scholarly journals Low-Dose Acrolein, an Endogenous and Exogenous Toxic Molecule, Inhibits Glucose Transport via an Inhibition of Akt-Regulated GLUT4 Signaling in Skeletal Muscle Cells

2021 ◽  
Vol 22 (13) ◽  
pp. 7228
Author(s):  
Ching-Chia Wang ◽  
Huang-Jen Chen ◽  
Ding-Cheng Chan ◽  
Chen-Yuan Chiu ◽  
Shing-Hwa Liu ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Glucose Metabolism ◽  
Glucose Tolerance ◽  
Protein Expression ◽  
Glucose Uptake ◽  
Glucose Transport ◽  
Diabetic Patients ◽  
Type 2 Diabetic Patients ◽  
Type 2 Diabetic

Urinary acrolein adduct levels have been reported to be increased in both habitual smokers and type-2 diabetic patients. The impairment of glucose transport in skeletal muscles is a major factor responsible for glucose uptake reduction in type-2 diabetic patients. The effect of acrolein on glucose metabolism in skeletal muscle remains unclear. Here, we investigated whether acrolein affects muscular glucose metabolism in vitro and glucose tolerance in vivo. Exposure of mice to acrolein (2.5 and 5 mg/kg/day) for 4 weeks substantially increased fasting blood glucose and impaired glucose tolerance. The glucose transporter-4 (GLUT4) protein expression was significantly decreased in soleus muscles of acrolein-treated mice. The glucose uptake was significantly decreased in differentiated C2C12 myotubes treated with a non-cytotoxic dose of acrolein (1 μM) for 24 and 72 h. Acrolein (0.5–2 μM) also significantly decreased the GLUT4 expression in myotubes. Acrolein suppressed the phosphorylation of glucose metabolic signals IRS1, Akt, mTOR, p70S6K, and GSK3α/β. Over-expression of constitutive activation of Akt reversed the inhibitory effects of acrolein on GLUT4 protein expression and glucose uptake in myotubes. These results suggest that acrolein at doses relevant to human exposure dysregulates glucose metabolism in skeletal muscle cells and impairs glucose tolerance in mice.

scholarly journals Leg and arm lactate and substrate kinetics during exercise

2003 ◽  
Vol 284 (1) ◽  
pp. E193-E205 ◽  
Author(s):  
G. van Hall ◽  
M. Jensen-Urstad ◽  
H. Rosdahl ◽  
H.-C. Holmberg ◽  
B. Saltin ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Glucose Uptake ◽  
Muscle Mass ◽  
Lactate Concentration ◽  
Whole Body ◽  
Glucose Turnover ◽  
Lactate Oxidation ◽  
Arterial Lactate ◽  
Lactate Uptake ◽  
High Lactate

To study the role of muscle mass and muscle activity on lactate and energy kinetics during exercise, whole body and limb lactate, glucose, and fatty acid fluxes were determined in six elite cross-country skiers during roller-skiing for 40 min with the diagonal stride (Continuous Arm + Leg) followed by 10 min of double poling and diagonal stride at 72–76% maximal O2 uptake. A high lactate appearance rate (Ra, 184 ± 17 μmol · kg−1 · min−1) but a low arterial lactate concentration (∼2.5 mmol/l) were observed during Continuous Arm + Leg despite a substantial net lactate release by the arm of ∼2.1 mmol/min, which was balanced by a similar net lactate uptake by the leg. Whole body and limb lactate oxidation during Continuous Arm + Leg was ∼45% at rest and ∼95% of disappearance rate and limb lactate uptake, respectively. Limb lactate kinetics changed multiple times when exercise mode was changed. Whole body glucose and glycerol turnover was unchanged during the different skiing modes; however, limb net glucose uptake changed severalfold. In conclusion, the arterial lactate concentration can be maintained at a relatively low level despite high lactate Ra during exercise with a large muscle mass because of the large capacity of active skeletal muscle to take up lactate, which is tightly correlated with lactate delivery. The limb lactate uptake during exercise is oxidized at rates far above resting oxygen consumption, implying that lactate uptake and subsequent oxidation are also dependent on an elevated metabolic rate. The relative contribution of whole body and limb lactate oxidation is between 20 and 30% of total carbohydrate oxidation at rest and during exercise under the various conditions. Skeletal muscle can change its limb net glucose uptake severalfold within minutes, causing a redistribution of the available glucose because whole body glucose turnover was unchanged.

scholarly journals An investigation of arterial insufficiency in the rat hindlimb Correlation of skeletal muscle bloodflow and glucose utilization in vivo

1986 ◽  
Vol 240 (2) ◽  
pp. 395-401 ◽  
Author(s):  
R A Challiss ◽  
D J Hayes ◽  
G K Radda
Keyword(s):  
Skeletal Muscle ◽  
Sciatic Nerve ◽  
Glucose Uptake ◽  
Nerve Stimulation ◽  
Linear Correlation ◽  
Glucose Utilization ◽  
Fold Increase ◽  
Artery Ligation ◽  
Sciatic Nerve Stimulation

Muscle bloodflow and the rate of glucose uptake and phosphorylation were measured in vivo in rats 7 days after unilateral femoral artery ligation and section. Bloodflow was determined by using radiolabelled microspheres. At rest, bloodflow to the gastrocnemius, plantaris and soleus muscles of the ligated limb was similar to their respective mean contralateral control values; however, bilateral sciatic nerve stimulation at 1 Hz caused a less pronounced hyperaemic response in the muscles of the ligated limb, being 59, 63 and 49% of their mean control values in the gastrocnemius, plantaris and soleus muscles respectively. The rate of glucose utilization was determined by using the 2-deoxy[3H]glucose method [Ferré, Leturque, Burnol, Penicaud & Girard (1985) Biochem. J. 228, 103-110]. At rest, the rate of glucose uptake and phosphorylation was statistically significantly increased in the gastrocnemius and soleus muscles of the ligated limb, being 126 and 140% of the mean control values respectively. Bilateral sciatic nerve stimulation at 1 Hz caused a 3-5-fold increase in the rate of glucose utilization by the ligated and contralateral control limbs; furthermore, the rate of glucose utilization was significantly increased in the muscles of the ligated limb, being 140, 129 and 207% of their mean control values respectively. For the range of bloodflow to normally perfused skeletal muscle at rest or during isometric contraction determined in the present study, a linear correlation between the rate of glucose utilization and bloodflow can be demonstrated. Applying similar methods of regression analysis to glucose utilization and bloodflow to muscles of the ligated limb reveals a similar linear correlation. However, the rate of glucose utilization at a given bloodflow is increased in muscles of the ligated limb, indicating an adaptation of skeletal muscle to hypoperfusion.

scholarly journals Glucose metabolism in perfused skeletal muscle. Pyruvate dehydrogenase activity in starvation, diabetes and exercise

1976 ◽  
Vol 158 (2) ◽  
pp. 203-210 ◽  
Author(s):  
S A Hagg ◽  
S I Taylor ◽  
N B Ruberman
Keyword(s):  
Skeletal Muscle ◽  
Dehydrogenase Activity ◽  
Pyruvate Dehydrogenase ◽  
Preceding Paper ◽  
Diabetic Rats ◽  
Pyruvate Dehydrogenase Kinase ◽  
Lactate Oxidation ◽  
Pyruvate Oxidation ◽  
Measured Activity ◽  
Exercise Induced

1. The interconversion of pyruvate dehydrogenase between its inactive phosphorylated and active dephosphorylated forms was studied in skeletal muscle. 2. Exercise, induced by electrical stimulation of the sciatic nerve (5/s), increased the measured activity of (active) pyruvate dehydrogenase threefold in intact anaesthetized rated within 2 min. No further increase was seen after 15 min of stimulation. 3. In the perfused rat hindquarter, (active) pyruvate dehydrogenase activity was decreased by 50% in muscle of starved and diabetic rats. Exercise produced a twofold increase in its activity in all groups; however, the relative differences between fed, starved and diabetic groups persisted. 4. Perfusion of muslce with acetoacetate (2 mM) decreased (active) pyruvate dehydrogenase activity by 50% at rest but not during exercise. 5. Whole-tissue concentrations of pyruvate and citrate, inhibitors of (active) pyruvate dehydrogenase kinase and (inactive) pyruvate dehydrogenase phosphate phosphatase respectively, were not altered by excerise. A decrease in the ATP/ADP ratio was observed, but did not appear to be sufficient to account for the increase in (active) pyruvate dehydrogenase activity. 6. The results suggest that interconversion of the phosphorylated and dephosphorylated forms of pyruvate dehydrogenase plays a major role in the regulation of pyruvate oxidation by eomparison of enzyme activity with measurements of lactate oxidation in the perfused hindquarter [see the preceding paper, Berger et al. (1976)] suggest that pyruvate oxidation is also modulated by the concentrations of substrates, cofactors and inhibitors of (active) pyruvate dehydrogenase activity.

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