scholarly journals Evaluation of the isolated perfused rat hindquarter for the study of muscle metabolism

1971 ◽  
Vol 124 (3) ◽  
pp. 639-651 ◽  
Author(s):  
N. B. Ruderman ◽  
C. R. S. Houghton ◽  
R. Hems
Keyword(s):  
Glucose Uptake ◽  
Nerve Stimulation ◽  
Ketone Bodies ◽  
Synthetic Medium ◽  
Lactate Production ◽  
Muscle Metabolism ◽  
High Rate ◽  
O2 Consumption ◽  
Glycerol Release

1. The metabolic integrity of a new isolated rat hindquarter preparation was studied. The hindquarter was perfused with a semi-synthetic medium containing aged human erythrocytes. More than 95% of the oxidative metabolism of the preparation was due to muscle, the remainder being due to bone, adipose tissue and, where present, skin. 2. Consumption of O2, glucose utilization, glycerol release and lactate production were similar in the presence and in the absence of the skin, indicating that the latter contributed little to the overall metabolism of the preparation. 3. After 40min of perfusion, tissue concentrations of creatine phosphate, ATP and ADP were similar to those found in muscle taken directly from intact animals. The muscle also appeared normal under the electron microscope. 4. The hindquarter did not lose K% to the medium during a 30min perfusion. In the presence of insulin it had a net K% uptake. 5. Insulin caused a sixfold increase in glucose uptake, stimulated O2 consumption by nearly 40% and depressed glycerol release to less than half the control value. 6. Bilateral sciatic-nerve stimulation caused severalfold increases in O2 consumption and lactate production. In the absence of insulin nerve stimulation also enhanced glucose uptake; in the presence of insulin it did not further increase the already high rate of glucose uptake. 7. Rates of lactate production and O2 consumption of the rat hindquarter in vivo and the isolated perfused hindquarter were very similar. 8. Ketone bodies were a major oxidative fuel in vivo of the hindquarter of a rat starved for 2 days. If the acetoacetate and 3-hydroxybutyrate removed by the tissue were completely oxidized, they would have accounted for 77% of the O2 consumption. 9. Acetoacetate accounted for 84% of the ketone bodies removed by the hindquarter in vivo even though its arterial concentration was half that of 3-hydroxybutyrate. 10. Similar rates of acetoacetate and 3-hydroxybutyrate utilization were observed in the perfused hindquarter. 11. Acetoacetate utilization by the perfused hindquarter was not diminished by the addition of either oleate or insulin to the perfusate. 12. Oxidation of glucose to CO2 accounted for less than 4% of the O2 consumed by the perfused hindquarter in both the presence and the absence of insulin. 13. The results indicate that the isolated perfused hindquarter is a useful tool for studying muscle metabolism. They also suggest that ketone bodies, if present in sufficient concentration, are the preferred oxidative fuel of resting muscle.

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 α-Hederin Inhibits the Growth of Lung Cancer A549 Cells in vitro and in vivo by Increasing SIRT6 Dependent Glycolysis

2020 ◽  
Author(s):  
cong fang ◽  
Yahui Liu ◽  
Lanying Chen ◽  
Yingying Luo ◽  
Yaru Cui ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Mouse Model ◽  
Protein Expression ◽  
Glucose Uptake ◽  
A549 Cells ◽  
Lactate Production ◽  
Tumor Xenograft ◽  
Xenograft Mouse Model ◽  
Atp Generation

Abstract Background: α-hederin an effective component of Pulsatilla chinensis (Bunge) Regel, Studies showed that α-hederin exert many pharmacological activities, However, the effect of α-hederin on metabolism is still unclear. This study aimed to illuminate the role of α-hederin in glucose metabolism in lung cancer cells and investigate the molecular mechanism of α-hederin. Methods: CCK8 and colony formation assays were employed to assess the anti-proliferative effects induced by α-hederin. Glucose uptake, ATP generation, and reduced lactate production were measured using kits, and an A549 tumor xenograft mouse model of lung cancer was used to assess the in vivo antitumor effect of α-hederin (5, 10 mg/kg). Glycolytic-related key enzymes hexokinase 2 (HK2), glucose transporters 1 (GLUT1), pyruvate kinase M2 (PKM2), lactate dehydrogenase A (LDHA), monocarboxylate transporter (MCT4), c-Myc, Hypoxia inducible factor-1α (HIF-1α) and Sirtuin 6 (SIRT6) protein expression were detected by western blotting and immunohistochemical staining and SIRT6 inhibitors was verified in A549 cells. Results: Our results showed that cell proliferation was significantly inhibited by α-hederin in a dose-dependent manner and that α-hederin inhibited glucose uptake and ATP generation and reduced lactate production. Furthermore, α-hederin remarkably inhibited HK2, GLUT1, PKM2, LDHA, MCT4, c-Myc, HIF-1α and activated SIRT6 protein expression. Using inhibitors, we proved that α-hederin inhibits glycolysis by activating SIRT6. Moreover, a tumor xenograft mouse model of lung cancer further confirmed that α-hederin inhibits lung cancer growth via inhibiting glycolysis in vivo. Conclusions: α-hederin inhibits the growth of non-small cell lung cancer A549 cells by inhibiting glycolysis. The mechanism of glycolysis inhibition includes α-hederin activating the expression of the glycolytic related protein SIRT6.

scholarly journals Effect of Antibody Binding and Agglutination on Human Platelet Glycolysis: Comparison with Thrombin and Epinephrine

Blood ◽  
1967 ◽  
Vol 30 (5) ◽  
pp. 617-624 ◽  
Author(s):  
SIMON KARPATKIN ◽  
GREGORY W. SISKIND
Keyword(s):  
Glucose Uptake ◽  
Krebs Cycle ◽  
Lactate Production ◽  
Ringer Solution ◽  
Human Platelets ◽  
Solution Ph ◽  
Atp Levels ◽  
Parallel Increase ◽  
Platelet Antibody

Abstract Freshly collected human platelets were washed in a modified human Ringer solution, pH 7.1, and aerobically incubated in the same media for 1 hour in the presence or absence of glucose. The effect of rabbit antihuman platelet antibody or univalent rabbit antihuman platelet antibody fragments (Fab) on platelet glycolysis was determined. Although ATP expenditure and glycogenolytic depletion were noted following platelet agglutination by antibody, these changes were not considered to be of major importance in the in vivo destruction of platelets. Univalent fragments were shown to bind to platelets without causing platelet agglutination or any detectable change in the glycolytic parameters. In contrast, intact platelet antibody resulted in platelet agglutination which was associated with an increase in lactate production and a decrease in ATP levels when platelets were incubated in the absence of glucose. Glucose-6-P levels did not change. When platelets were incubated in the presence of glucose, glucose uptake increased, ATP levels declined and glucose-6-P levels were unchanged. However, the increased glucose uptake was not accompanied by a parallel increase in lactate production as in the case with thrombin or epinephrine-induced agglutination of platelets. It is postulated that platelet antibody activates a glucose-requiring nonglycolytic pathway, perhaps the hexosemonophosphate shunt or the Krebs’ cycle.

Adenosine regulates blood flow and glucose uptake in adipose tissue of dogs

1986 ◽  
Vol 250 (6) ◽  
pp. H1127-H1135
Author(s):  
S. E. Martin ◽  
E. L. Bockman
Keyword(s):  
Blood Flow ◽  
Adipose Tissue ◽  
Glucose Uptake ◽  
Indirect Effect ◽  
Glycerol Release ◽  
Anesthetized Dogs ◽  
Tissue Contents ◽  
Fat Pads

Intravenous norepinephrine increases glycerol release and blood flow in adipose tissue. The vasodilation may be an indirect effect of norepinephrine through the production of adenosine. Adenosine increases glucose uptake and inhibits lipolysis in vitro. To test whether adenosine regulates blood flow and/or metabolism in vivo, adenosine deaminase (ADA) was infused intra-arterially into the inguinal fat pads of anesthetized dogs. In unstimulated tissues, ADA (n = 7) significantly increased vascular resistance and significantly decreased glucose uptake compared with the effects of a control (boiled deaminase, n = 6) infusion. ADA completely blocked the norepinephrine-induced vasodilation (n = 6). No potentiation of basal or catecholamine-stimulated lipolysis was observed with ADA. The presence of ADA in the interstitial space was verified by analysis of lymph effluents. Interstitial levels of ADA were inversely correlated with the tissue contents of adenosine. These data support the hypothesis that adenosine is a regulator of blood flow in basal and stimulated adipose tissue. Adenosine also appears to regulate glucose uptake, but not lipolysis, in vivo.

Chronic and acute ethanol impair the in vivo glucose uptake by lactating rat mammary gland

1987 ◽  
Vol 7 (10) ◽  
pp. 777-781 ◽  
Author(s):  
S. Vilaró ◽  
O. Viñas ◽  
E. Herrera ◽  
X. Remesar
Keyword(s):  
Mammary Gland ◽  
Glucose Uptake ◽  
Ketone Bodies ◽  
Direct Effects ◽  
Acute Ethanol ◽  
Rat Mammary Gland

Chronic and acute ethanol treatments increased the 3-hydroxybutyrate uptake by lactating rat mammary gland as a consequence of its high afferent concentration, without changing its relative extraction. The uptake of glucose was inhibited in the ethanol treated animals due to intrinsic alterations in the mammary gland metabolism as indicated by the decreased relative extraction and unchanged afferent concentration. These results would suggest that the elevated uptake of ketone bodies in ethanol-treated rats can be responsible, at least in part, for the decrease in glucose uptake by lactating rat mammary gland, although other direct effects of ethanol may be implied.

Altered muscle metabolism associated with vasoconstriction in spontaneously hypertensive rats

1998 ◽  
Vol 275 (6) ◽  
pp. E1007-E1015 ◽  
Author(s):  
Ji-Ming Ye ◽  
Eric Q. Colquhoun
Keyword(s):  
Glucose Uptake ◽  
Spontaneously Hypertensive Rats ◽  
Perfusion Pressure ◽  
Lactate Production ◽  
Ang Ii ◽  
Hypertensive Rats ◽  
Response Curves ◽  
Spontaneously Hypertensive ◽  
Wistar Kyoto

In the rat muscle vascular bed, vasoconstrictors either increase or decrease oxygen consumption (V˙o 2). The present study compared the effects of norepinephrine (NE), angiotensin II (ANG II), and 5-hydroxytryptamine (5-HT) on vasoconstriction-associated metabolism in the constant-flow perfused hindlimb of spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) in the absence of insulin. Basal perfusion pressure,V˙o 2, glucose uptake, and lactate production were increased by 21.4, 11.9, 46.4, and 44.9% ( P < 0.05 for all), respectively, in SHR, which also had higher blood pressure and metabolic rate ( P < 0.05) in vivo. Dose-response curves for NE-induced perfusion pressure,V˙o 2, and lactate production in SHR were shifted to the left compared with WKY. Associated with the increased perfusion pressure, NE-inducedV˙o 2 and glucose uptake were both decreased ( P < 0.01), particularly at high concentrations. These differences were unaffected by 10 μM propranolol but were all diminished by further addition of prazosin (2.5 nM). ANG II stimulatedV˙o 2, glucose uptake, and lactate production in both strains, but the increased lactate production was smaller in SHR ( P < 0.05) with a proportional decrease ( P< 0.05) in glucose uptake. Conversely, 5-HT decreasedV˙o 2 in both strains ( P < 0.01), and this effect was greater in SHR ( P < 0.01). These data suggest that SHR muscle thermogenesis and glucose uptake are impaired during vasoconstriction, especially in response to NE.

scholarly journals Rapid inhibition by intragastric triolein of the re-activation of glucose utilization and lipogenesis in the mammary gland during the starved-refed transition in lactating rats. Evidence for a direct effect of oral lipid on mammary tissue

1988 ◽  
Vol 250 (1) ◽  
pp. 269-276 ◽  
Author(s):  
S W Mercer ◽  
D H Williamson
Keyword(s):  
Mammary Gland ◽  
Glucose Uptake ◽  
Time Course ◽  
Glucose Utilization ◽  
Lactate Production ◽  
Dietary Lipid ◽  
Mammary Tissue ◽  
Phosphofructokinase Activity ◽  
Fructose 1,6 Bisphosphate

1. Oral administration of triacylglycerol (triolein) to starved/chow-refed lactating rats suppressed the lipogenic switch-on in the mammary gland in vivo. 2. A time-course study revealed that triolein, administered at 30 min after the onset of refeeding, had no influence on lipogenic rate in the mammary gland between 30 and 60 min, but markedly decreased it between 60 and 90 min. Glucose uptake by the mammary gland (arteriovenous difference) increased by 30 min of refeeding, as did lactate production. Between 30 and 90 min glucose uptake remained high in the control animals, but glucose uptake and net C3-unit uptake were decreased in the triolein-loaded animals by 90 min. 3. Triolein increased [glucose 6-phosphate] in the gland and simultaneously decreased [fructose 1,6-bisphosphate], indicative of a decrease in phosphofructokinase activity. This cross-over occurred at 60 min, i.e. immediately before the inhibition of lipogenesis, and by 90 min had reached ‘starved’ values. 4. Triolein had no effect on plasma [insulin] nor on whole-blood [glucose], [lactate] or [3−hydroxybutyrate]; a small increase in [acetoacetate] was observed. 5. Infusion of the lipoprotein lipase inhibitor, Triton WR1339, abolished the suppression of mammary-gland lipogenesis by triolein and the increase in the [glucose 6-phosphate]/[fructose 1,6-bisphosphate] ratio, suggesting a direct influence of dietary lipid on mammary-gland glucose utilization and phosphofructokinase activity.

scholarly journals Aerobic lactate production by mammary tissue

1975 ◽  
Vol 146 (1) ◽  
pp. 273-275 ◽  
Author(s):  
A R Elkin ◽  
N J Kuhn
Keyword(s):  
Glucose Uptake ◽  
Lactate Production ◽  
Mammary Glands ◽  
Mammary Tissue ◽  
Metabolic Derangement ◽  
Intact Tissue ◽  
Lactate Formation ◽  
Normal Feature

Glucose uptake and L-lactate production were measured in cell, slice and intact tissue preparations of mammary glands from late-pregnant and lactating rats. The tissues showed extensive conversion of glucose into lactate in vitro, but not in vivo. Therefore aerobic lactate formation is not a normal feature of mammary tissue, but occurs in vitro as the result of some metabolic derangement.

scholarly journals The reciprocal loop of MALAT1 and HIF-1α facilitates gemcitabine resistance in pancreatic cancer by enhancing glycolysis

2021 ◽  
Author(s):  
Zhengle Zhang ◽  
Hengqiang Zhao ◽  
Wenbin Yang ◽  
Chuanbing Zhao ◽  
Zhigang Tang ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Glucose Uptake ◽  
Aerobic Glycolysis ◽  
Critical Role ◽  
Lactate Production ◽  
Xenograft Model ◽  
Glycolytic Enzymes ◽  
Gemcitabine Resistance ◽  
Pancreatic Cancer Cells

Abstract Background: Profound chemoresistance is a prominent and intractable problem in pancreatic cancer. Gemcitabine, a first-line chemotherapeutic drug for pancreatic cancer, has provided only minimal benefits for patients; however, the underlying mechanisms remain to be investigated. Enhanced aerobic glycolysis has been suggested to be correlated with the phenotype of drug resistance, while MALAT1 has been indicated to be associated with poor gemcitabine response. However, the implicated regulatory mechanisms still need to be further explored.Methods: The mRNA level of MALAT1, HIF-1α, and glycolytic enzymes were analyzed by qRT-PCR. The protein level of HIF-1α and glycolytic enzymes were detected by western blot analysis. The glucose uptake and lactate level were measured by glucose uptake and lactate production assay, respectively. The cell apoptosis was evaluated by apoptosis analysis using Annexin V/propidium iodide (PI) staining. The sensitivity to gemcitabine was measured by MTT assay. The binding of HIF-1α to the promoter of MALAT1 was tested by ChIP assay. The xenograft model of pancreatic cancer was established to examine the combined effect of MALAT1 knockdown and gemcitabine chemotherapy in vivo. Results: In this study, we showed that low concentrations of gemcitabine promoted the expression of key glycolytic enzymes, such as GLUT1, HK2, and LDHA, as well as glucose uptake and lactate production in pancreatic cancer cells, while inhibition of glycolysis suppressed gemcitabine chemoresistance. In addition, we found that MALAT1 expression was induced by gemcitabine and mediated enhanced glycolysis and chemoresistance. Silencing MALAT1 inhibited the level of gemcitabine-induced HIF-1α expression and reinforced gemcitabine-induced apoptosis in vitro and in vivo. Furthermore, HIF-1α could bind the promoter of MALAT1 transcriptionally and mediate the glycolysis induced by gemcitabine. Conclusions: Our data suggest a critical role of glycolytic metabolism in acquired gemcitabine resistance through the positive feedback loop of MALAT1 and the HIF-1α signaling pathway. Our results will provide a basis for developing potential therapeutic targets to reverse gemcitabine resistance.

β-Hydroxybutyrate inhibits insulin-mediated glucose transport in mouse oxidative muscle

2010 ◽  
Vol 299 (3) ◽  
pp. E364-E373 ◽  
Author(s):  
Takashi Yamada ◽  
Shi-Jin Zhang ◽  
Håkan Westerblad ◽  
Abram Katz
Keyword(s):  
Protein Kinase ◽  
Insulin Receptor ◽  
Glucose Uptake ◽  
Glucose Transport ◽  
Insulin Action ◽  
Ketone Body ◽  
Ketone Bodies ◽  
Dependent Manner ◽  
Concentration Dependent Manner

Blood ketone body levels increase during starvation and untreated diabetes. Here we tested the hypothesis that ketone bodies directly inhibit insulin action in skeletal muscle. We investigated the effect of d,l-β-hydroxybutyrate (BOH; the major ketone body in vivo) on insulin-mediated glucose uptake (2-deoxyglucose) in isolated mouse soleus (oxidative) and extensor digitorum longus (EDL; glycolytic) muscle. BOH inhibited insulin-mediated glucose uptake in soleus (but not in EDL) muscle in a time- and concentration-dependent manner. Following 19.5 h of exposure to 5 mM BOH, insulin-mediated (20 mU/ml) glucose uptake was inhibited by ∼90% (substantial inhibition was also observed in 3- O-methylglucose transport). The inhibitory effect of BOH was reproduced with d- but not l-BOH. BOH did not significantly affect hypoxia- or AICAR-mediated (activates AMP-dependent protein kinase) glucose uptake. The BOH effect did not require the presence/utilization of glucose since it was also seen when glucose in the medium was substituted with pyruvate. To determine whether the BOH effect was mediated by oxidative stress, an exogenous antioxidant (1 mM tempol) was used; however, tempol did not reverse the BOH effect on insulin action. BOH did not alter the levels of total tissue GLUT4 protein or insulin-mediated tyrosine phosphorylation of the insulin receptor and insulin receptor substrate-1 but blocked insulin-mediated phosphorylation of protein kinase B by ∼50%. These data demonstrate that BOH inhibits insulin-mediated glucose transport in oxidative muscle by inhibiting insulin signaling. Thus ketone bodies may be potent diabetogenic agents in vivo.

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