The relationship between insulin binding, insulin activation of insulin-receptor tyrosine kinase, and insulin stimulation of glucose uptake in isolated rat adipocytes. Effects of isoprenaline

We have studied the relationship between insulin activation of insulin-receptor kinase and insulin stimulation of glucose uptake in isolated rat adipocytes. Glucose uptake was half-maximally or maximally stimulated, respectively, when only 4% or 14% of the maximal kinase activity had been reached. To investigate this relationship also under conditions where the insulin effect on activation of receptor kinase was decreased, the adipocytes were exposed to 10 microM-isoprenaline alone or with 5 micrograms of adenosine deaminase/ml. An approx. 30% (isoprenaline) or approx. 50% (isoprenaline + adenosine deaminase) decrease in the insulin effect on receptor kinase activity was found at insulin concentrations between 0.4 and 20 ng/ml, and this could not be explained by decreased insulin binding. The decreased insulin-effect on kinase activity was closely correlated with a loss of insulin-sensitivity of glucose uptake. Moreover, our data indicate that the relation between receptor kinase activity and glucose uptake (expressed as percentage of maximal uptake) remained unchanged. The following conclusions were drawn. (1) If activation of receptor kinase stimulates glucose uptake, only 14% of the maximal kinase activity is sufficient for maximal stimulation. (2) Isoprenaline decreases the coupling efficiency between insulin binding and receptor-kinase activation, this being accompanied by a corresponding decrease in sensitivity of glucose uptake. (3) Our data indicate that the signalling for glucose uptake is closely related to receptor-kinase activity, even when the coupling efficiency between insulin binding and kinase activation is altered. They thus support the hypothesis that receptor-kinase activity reflects the signal which originates from the receptor and which is transduced to the glucose-transport system.

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Effect of a high-fat-sucrose diet on in vivo insulin receptor kinase activation

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1990.259.1.e111 ◽

1990 ◽

Vol 259 (1) ◽

pp. E111-E116 ◽

Cited By ~ 1

Author(s):

J. J. Boyd ◽

I. Contreras ◽

M. Kern ◽

E. B. Tapscott ◽

D. L. Downes ◽

...

Keyword(s):

Insulin Resistance ◽

Insulin Receptor ◽

Glucose Uptake ◽

Kinase Activity ◽

Insulin Binding ◽

Receptor Kinase ◽

High Fat ◽

Glucose Injection ◽

Insulin Receptor Kinase

Insulin-stimulated glucose uptake into muscle is depressed by high-fat-sucrose (HFS) feeding of rats. To investigate the mechanism of this insulin resistance, the in vivo activation of the insulin receptor kinase in liver and muscle of control and HFS-fed rats was determined. Rats were injected with glucose and insulin and killed 0, 5, 15, and 30 min after injection. Insulin binding was not changed in partially purified receptors from muscle of HFS rats. In control rats insulin receptor kinase activity was maximally stimulated threefold in liver at 5 min and fourfold in muscle at 15 min after insulin-glucose injection. The insulin-stimulated tyrosine kinase activity of receptors isolated from the liver of rats fed the HFS diet was decreased by 30% in comparison with the controls. In contrast, receptors isolated from muscle did not show any difference in basal or insulin-stimulated kinase activity between HFS-fed and control rats. Decreased in vivo activation of the insulin receptor kinase may be at least partially responsible for insulin resistance in liver. Because insulin binding and insulin stimulation of receptor kinase were normal in muscle of HFS-fed animals, it is concluded that the insulin resistance of glucose uptake into muscle is caused by a defect distal to the insulin receptor.

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TNF-α impairs insulin signaling and insulin stimulation of glucose uptake in C2C12muscle cells

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1999.276.5.e849 ◽

1999 ◽

Vol 276 (5) ◽

pp. E849-E855 ◽

Cited By ~ 47

Author(s):

Luis F. del Aguila ◽

Kevin P. Claffey ◽

John P. Kirwan

Keyword(s):

Insulin Resistance ◽

Skeletal Muscle ◽

Glucose Uptake ◽

Tyrosine Phosphorylation ◽

Insulin Signaling ◽

Insulin Stimulation ◽

Kinase Activation ◽

Tnf Α ◽

Impaired Insulin ◽

Stimulation Of

Physiological stressors such as sepsis and tissue damage initiate an acute immune response and cause transient systemic insulin resistance. This study was conducted to determine whether tumor necrosis factor-α (TNF-α), a cytokine produced by immune cells during skeletal muscle damage, decreases insulin responsiveness at the cellular level. To examine the molecular mechanisms associated with TNF-α and insulin action, we measured insulin receptor substrate (IRS)-1- and IRS-2-mediated phosphatidylinositol 3-kinase (PI 3-kinase) activation, IRS-1-PI 3-kinase binding, IRS-1 tyrosine phosphorylation, and the phosphorylation of two mitogen-activated protein kinases (MAPK, known as p42MAPK and p44MAPK) in cultured C2C12myotubes. Furthermore, we determined the effects of TNF-α on insulin-stimulated 2-deoxyglucose (2-DG) uptake. We observed that TNF-α impaired insulin stimulation of IRS-1- and IRS-2-mediated PI 3-kinase activation by 54 and 55% ( P< 0.05), respectively. In addition, TNF-α decreased insulin-stimulated IRS-1 tyrosine phosphorylation by 40% ( P < 0.05). Furthermore, TNF-α repressed insulin-induced p42MAPKand p44MAPK tyrosine phosphorylation by 81% ( P < 0.01). TNF-α impairment of insulin signaling activation was accompanied by a decrease ( P < 0.05) in 2-DG uptake in the muscle cells (60 ± 4 vs. 44 ± 6 pmol ⋅ min−1 ⋅ mg−1). These data suggest that increases in TNF-α may cause insulin resistance in skeletal muscle by inhibiting IRS-1- and IRS-2-mediated PI 3-kinase activation as well as p42MAPK and p44MAPK tyrosine phosphorylation, leading to impaired insulin-stimulated glucose uptake.

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Stimulation of insulin-like growth factor II receptor binding and insulin receptor kinase activity in rat adipocytes. Effects of vanadate and H2O2.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)47556-4 ◽

1987 ◽

Vol 262 (17) ◽

pp. 8252-8256 ◽

Cited By ~ 10

Author(s):

S Kadota ◽

I G Fantus ◽

G Deragon ◽

H J Guyda ◽

B I Posner

Keyword(s):

Growth Factor ◽

Insulin Receptor ◽

Receptor Binding ◽

Kinase Activity ◽

Receptor Kinase ◽

Rat Adipocytes ◽

Factor Ii ◽

Insulin Receptor Kinase ◽

Insulin Receptor Kinase Activity ◽

Stimulation Of

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Effects of exercise training on the relationship between insulin binding and insulin-stimulated tyrosine kinase activity in rat skeletal muscle

Metabolism ◽

10.1016/0026-0495(89)90128-5 ◽

1989 ◽

Vol 38 (4) ◽

pp. 376-386 ◽

Cited By ~ 11

Author(s):

Rosa F. Santos ◽

Carl E. Mondon ◽

Gerald M. Reaven ◽

Salman Azhar

Keyword(s):

Skeletal Muscle ◽

Exercise Training ◽

Tyrosine Kinase ◽

Kinase Activity ◽

Insulin Binding ◽

Rat Skeletal Muscle ◽

Tyrosine Kinase Activity ◽

The Relationship

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Tyrosine kinase activity of liver insulin receptor is inhibited in rats at term gestation

Biochemical Journal ◽

10.1042/bj2630267 ◽

1989 ◽

Vol 263 (1) ◽

pp. 267-272 ◽

Cited By ~ 9

Author(s):

C Martínez ◽

P Ruiz ◽

A Andrés ◽

J Satrústegui ◽

J M Carrascosa

Keyword(s):

Insulin Receptor ◽

Kinase Activity ◽

Insulin Signalling ◽

Insulin Receptors ◽

Insulin Binding ◽

Late Gestation ◽

Receptor Kinase ◽

Pregnant Rats ◽

Insulin Resistant ◽

32P Incorporation

Late gestation is associated with insulin resistance in rats and humans. It has been reported that rats at term gestation show active hepatic gluconeogenesis and glycogenolysis, and diminished lipogenesis, despite normal or mildly elevated plasma insulin concentrations, indicating a state of resistance to the hormone action. Since autophosphorylation of the insulin receptor has been reported to play a key role in the hormone signal transduction, we have partially purified plasma-membrane liver insulin receptors from virgin and 22-day-pregnant rats and studied their binding and kinase activities. (1) Insulin binding to partially purified receptors does not appear to be influenced by gestation, as indicated by the observed KD and Bmax. values. (2) The rate of autophosphorylation and the maximal 32P incorporation into the receptor beta-subunit from pregnant rats at saturating concentrations of insulin are markedly decreased with respect to the corresponding values for virgin rats. (3) The diminished autophosphorylation rate was due to a decreased responsiveness of the kinase activity to the action of insulin. (4) Phosphorylation of the exogenous substrates casein and poly(Glu80Tyr20) by insulin-receptor kinase was also less when receptors from pregnant rats were used. These results show the existence of an impairment at the receptor kinase level of the insulin signalling mechanism that might be related to the insulin-resistant state characteristic of term gestation in rats.

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Ectopic Expression of Protein Kinase CβII, -δ, and -ϵ, but Not -βI or -ζ, Provide for Insulin Stimulation of Glucose Uptake in NIH-3T3 Cells

Archives of Biochemistry and Biophysics ◽

10.1006/abbi.1999.1472 ◽

1999 ◽

Vol 372 (1) ◽

pp. 69-79 ◽

Cited By ~ 15

Author(s):

Denise R. Cooper ◽

James E. Watson ◽

Niketa Patel ◽

Philip Illingworth ◽

Mildred Acevedo-Duncan ◽

...

Keyword(s):

Protein Kinase ◽

Glucose Uptake ◽

Ectopic Expression ◽

3T3 Cells ◽

Insulin Stimulation ◽

Nih 3T3 ◽

Stimulation Of ◽

Nih 3T3 Cells

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Two Distinct Phosphorylation Pathways Have Additive Effects on Abl Family Kinase Activation

Molecular and Cellular Biology ◽

10.1128/mcb.23.11.3884-3896.2003 ◽

2003 ◽

Vol 23 (11) ◽

pp. 3884-3896 ◽

Cited By ~ 93

Author(s):

Keith Q. Tanis ◽

Darren Veach ◽

Henry S. Duewel ◽

William G. Bornmann ◽

Anthony J. Koleske

Keyword(s):

Tyrosine Kinases ◽

Kinase Activity ◽

Intramolecular Interactions ◽

Activation Loop ◽

Additive Effects ◽

Nonreceptor Tyrosine Kinase ◽

Kinase Activation ◽

Surface Receptors ◽

Nonreceptor Tyrosine Kinases ◽

Stimulation Of

ABSTRACT The activities of the related Abl and Arg nonreceptor tyrosine kinases are kept under tight control in cells, but exposure to several different stimuli results in a two- to fivefold stimulation of kinase activity. Following the breakdown of inhibitory intramolecular interactions, Abl activation requires phosphorylation on several tyrosine residues, including a tyrosine in its activation loop. These activating phosphorylations have been proposed to occur either through autophosphorylation by Abl in trans or through phosphorylation of Abl by the Src nonreceptor tyrosine kinase. We show here that these two pathways mediate phosphorylation at distinct sites in Abl and Arg and have additive effects on Abl and Arg kinase activation. Abl and Arg autophosphorylate at several sites outside the activation loop, leading to 5.2- and 6.2-fold increases in kinase activity, respectively. We also find that the Src family kinase Hck phosphorylates the Abl and Arg activation loops, leading to an additional twofold stimulation of kinase activity. The autoactivation pathway may allow Abl family kinases to integrate or amplify cues relayed by Src family kinases from cell surface receptors.

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Insulin directly stimulates mitochondrial glucose oxidation in the heart

Cardiovascular Diabetology ◽

10.1186/s12933-020-01177-3 ◽

2020 ◽

Vol 19 (1) ◽

Author(s):

Qutuba G. Karwi ◽

Cory S. Wagg ◽

Tariq R. Altamimi ◽

Golam M. Uddin ◽

Kim L. Ho ◽

...

Keyword(s):

Protein Kinase ◽

Glucose Uptake ◽

Glucose Oxidation ◽

Glycogen Synthase ◽

Acid Oxidation ◽

Mouse Heart ◽

Insulin Stimulation ◽

Direct Stimulation ◽

Gsk 3Β ◽

Stimulation Of

Abstract Background Glucose oxidation is a major contributor to myocardial energy production and its contribution is orchestrated by insulin. While insulin can increase glucose oxidation indirectly by enhancing glucose uptake and glycolysis, it also directly stimulates mitochondrial glucose oxidation, independent of increasing glucose uptake or glycolysis, through activating mitochondrial pyruvate dehydrogenase (PDH), the rate-limiting enzyme of glucose oxidation. However, how insulin directly stimulates PDH is not known. To determine this, we characterized the impacts of modifying mitochondrial insulin signaling kinases, namely protein kinase B (Akt), protein kinase C-delta (PKC-δ) and glycogen synthase kinase-3 beta (GSK-3β), on the direct insulin stimulation of glucose oxidation. Methods We employed an isolated working mouse heart model to measure the effect of insulin on cardiac glycolysis, glucose oxidation and fatty acid oxidation and how that could be affected when mitochondrial Akt, PKC-δ or GSK-3β is disturbed using pharmacological modulators. We also used differential centrifugation to isolate mitochondrial and cytosol fraction to examine the activity of Akt, PKC-δ and GSK-3β between these fractions. Data were analyzed using unpaired t-test and two-way ANOVA. Results Here we show that insulin-stimulated phosphorylation of mitochondrial Akt is a prerequisite for transducing insulin’s direct stimulation of glucose oxidation. Inhibition of mitochondrial Akt completely abolishes insulin-stimulated glucose oxidation, independent of glucose uptake or glycolysis. We also show a novel role of mitochondrial PKC-δ in modulating mitochondrial glucose oxidation. Inhibition of mitochondrial PKC-δ mimics insulin stimulation of glucose oxidation and mitochondrial Akt. We also demonstrate that inhibition of mitochondrial GSK3β phosphorylation does not influence insulin-stimulated glucose oxidation. Conclusion We identify, for the first time, insulin-stimulated mitochondrial Akt as a prerequisite transmitter of the insulin signal that directly stimulates cardiac glucose oxidation. These novel findings suggest that targeting mitochondrial Akt is a potential therapeutic approach to enhance cardiac insulin sensitivity in condition such as heart failure, diabetes and obesity.

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Insulin resistance of glucose metabolism in isolated brown adipocytes of lactating rats. Evidence for a post-receptor defect in insulin action

Biochemical Journal ◽

10.1042/bj2650511 ◽

1990 ◽

Vol 265 (2) ◽

pp. 511-517 ◽

Cited By ~ 6

Author(s):

A F Burnol ◽

S Ebner ◽

J Kandé ◽

J Girard

Keyword(s):

Insulin Resistance ◽

Glucose Metabolism ◽

Tyrosine Kinase ◽

Pyruvate Dehydrogenase ◽

Kinase Activity ◽

Insulin Stimulation ◽

Tyrosine Kinase Activity ◽

Brown Adipocytes ◽

Insulin Receptor Tyrosine Kinase ◽

Stimulation Of

The mechanism responsible for the insulin resistance described in vivo in brown adipose tissue (BAT) of lactating rats was investigated. The effect of insulin on glucose metabolism was studied on isolated brown adipocytes of non-lactating and lactating rats. Insulin stimulation of total glucose metabolism is 50% less in brown adipocytes from lactating than from non-lactating rats. This reflects a decreased effect of insulin on glucose oxidation and lipogenesis. However, the effect of noradrenaline (8 microM) on glucose metabolism was preserved in brown adipocytes from lactating rats as compared with non-lactating rats. The number of insulin receptors is similar in BAT of lactating and non-lactating rats. The insulin-receptor tyrosine kinase activity is not altered during lactation, for receptor autophosphorylation as well as tyrosine kinase activity towards the synthetic peptide poly(Glu4-Tyr1). The defect in the action of insulin is thus localized at a post-receptor level. The insulin stimulation of pyruvate dehydrogenase activity during euglycaemic/hyperinsulinaemic clamps is 2-fold lower in BAT from lactating than from non-lactating rats. However, the percentage of active form of pyruvate dehydrogenase is similar in non-lactating and lactating rats (8.6% versus 8.9% in the basal state, and 37.0% versus 32.3% during the clamp). A decrease in the amount of pyruvate dehydrogenase is likely to be involved in the insulin resistance described in BAT during lactation.

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