Acute exercise increases the number of plasma membrane glucose transporters in rat skeletal muscle

This study was done to evaluate the effect of insulin on sugar transport into skeletal muscle after exercise. The permeability of rat epitrochlearis muscle to 3-O-methylglucose (3-MG) was measured after exposure to a range of insulin concentrations 30, 60, and 180 min after a bout of exercise. Thirty and 60 min after exercise, the effects of exercise and insulin on 3-MG transport were additive over a wide range of insulin concentrations, with no increase in sensitivity or responsiveness to insulin. After 180 min, when approximately 66% of the exercise-induced increase in sugar transport had worn off, both the responsiveness and sensitivity of the glucose transport process to insulin were increased. These findings appear compatible with the hypothesis that the actions of exercise and insulin result in activation and/or translocation into the plasma membrane of two separate pools of glucose transporters in mammalian skeletal muscle.

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Glycaemia regulates the glucose transporter number in the plasma membrane of rat skeletal muscle

Biochemical Journal ◽

10.1042/bj2840341 ◽

1992 ◽

Vol 284 (2) ◽

pp. 341-348 ◽

Cited By ~ 45

Author(s):

D Dimitrakoudis ◽

T Ramlal ◽

S Rastogi ◽

M Vranic ◽

A Klip

Keyword(s):

Skeletal Muscle ◽

Plasma Membrane ◽

Glucose Transport ◽

Transport System ◽

Plasma Membranes ◽

Glucose Transporter ◽

Cytochalasin B ◽

Glucose Transporters ◽

Mrna Levels ◽

Rat Skeletal Muscle

The number of glucose transporters was measured in isolated membranes from diabetic-rat skeletal muscle to determine the role of circulating blood glucose levels in the control of glucose uptake into skeletal muscle. Three experimental groups of animals were investigated in the post-absorptive state: normoglycaemic/normoinsulinaemic, hyperglycaemic/normoinsulinaemic and hyperglycaemic/normoinsulinaemic made normoglycaemic/normoinsulinaemic by phlorizin treatment. Hyperglycaemia caused a reversible decrease in total transporter number, as measured by cytochalasin B binding, in both plasma membranes and internal membranes of skeletal muscle. Changes in GLUT4 glucose transporter protein mirrored changes in cytochalasin B binding in plasma membranes. However, there was no recovery of GLUT4 levels in intracellular membranes with correction of glycaemia. GLUT4 mRNA levels decreased with hyperglycaemia and recovered only partially with correction of glycaemia. Conversely, GLUT1 glucose transporters were only detectable in the plasma membranes; the levels of this protein varied directly with glycaemia, i.e. in the opposite direction to GLUT4 glucose transporters. This study demonstrates that hyperglycaemia, in the absence of hypoinsulinaemia, is capable of down-regulating the glucose transport system in skeletal muscle, the major site of peripheral resistance to insulin-stimulated glucose transport in diabetes. Furthermore, correction of hyperglycaemia causes a complete restoration of the transport system in the basal state (determined by the transporter number in the plasma membrane), but possibly only an incomplete recovery of the transport system's ability to respond to insulin (since there is no recovery of GLUT4 levels in the intracellular membrane insulin-responsive transporter pool). Finally, the effect of hyperglycaemia is specific for glucose transporter isoforms, with GLUT1 and GLUT4 proteins varying respectively in parallel and opposite directions to levels of glycaemia.

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505 HKII GENE TRANSCRIPTION IS INCREASED BY ACUTE EXERCISE IN RAT SKELETAL MUSCLE

Medicine & Science in Sports & Exercise ◽

10.1249/00005768-199405001-00506 ◽

1994 ◽

Vol 26 (Supplement) ◽

pp. S90 ◽

Cited By ~ 1

Author(s):

Robert M. O??Doherty ◽

Deanna P. Bracy ◽

Daryl K. Granner ◽

David H. Wasserman

Keyword(s):

Skeletal Muscle ◽

Gene Transcription ◽

Acute Exercise ◽

Rat Skeletal Muscle

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Exercise increases the plasma membrane content of the Na+ -K+ pump and its mRNA in rat skeletal muscles

Journal of Applied Physiology ◽

10.1152/jappl.1996.80.2.699 ◽

1996 ◽

Vol 80 (2) ◽

pp. 699-705 ◽

Cited By ~ 47

Author(s):

T. Tsakiridis ◽

P. P. Wong ◽

Z. Liu ◽

C. D. Rodgers ◽

M. Vranic ◽

...

Keyword(s):

Skeletal Muscle ◽

Plasma Membrane ◽

Skeletal Muscles ◽

Plasma Membranes ◽

Acute Exercise ◽

Treadmill Running ◽

Type I ◽

Mrna Levels ◽

Subunit Mrna ◽

White Type

Muscle fibers adapt to ionic challenges of exercise by increasing the plasma membrane Na+-K+ pump activity. Chronic exercise training has been shown to increase the total amount of Na+-K+ pumps present in skeletal muscle. However, the mechanism of adaptation of the Na+-K+ pump to an acute bout of exercise has not been determined, and it is not known whether it involves alterations in the content of plasma membrane pump subunits. Here we examine the effect of 1 h of treadmill running (20 m/min, 10% grade) on the subcellular distribution and expression of Na+-K+ pump subunits in rat skeletal muscles. Red type I and IIa (red-I/IIa) and white type IIa and IIb (white-IIa/IIb) hindlimb muscles from resting and exercised female Sprague-Dawley rats were removed for subcellular fractionation. By homogenization and gradient centrifugation, crude membranes and purified plasma membranes were isolated and subjected to gel electrophoresis and immunoblotting by using pump subunit-specific antibodies. Furthermore, mRNA was isolated from specific red type I (red-I) and white type IIb (white-IIb) muscles and subjected to Northern blotting by using subunit-specific probes. In both red-I/IIa and white-IIa/IIb muscles, exercise significantly raised the plasma membrane content of the alpha1-subunit of the pump by 64 +/- 24 and 55 +/- 22%, respectively (P < 0.05), and elevated the alpha2-polypeptide by 43 +/- 22 and 94 +/- 39%, respectively (P < 0.05). No significant effect of exercise could be detected on the amount of these subunits in an internal membrane fraction or in total membranes. In addition, exercise significantly increased the alpha1-subunit mRNA in red-I muscle (by 50 +/- 7%; P < 0.05) and the beta2-subunit mRNA in white-IIb muscles (by 64 +/- 19%; P < 0.01), but the alpha2- and beta1-mRNA levels were unaffected in this time period. We conclude that increased presence of alpha1- and alpha2-polypeptides at the plasma membrane and subsequent elevation of the alpha1- and beta2-subunit mRNAs may be mechanisms by which acute exercise regulates the Na+-K+ pump of skeletal muscle.

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Expression of αB-crystallin, HSP 27, HSP 70 and Cytochrome c in rat skeletal muscle following acute exercise between training and nontraining group

Exercise Science ◽

10.15857/ksep.2009.18.4.455 ◽

2009 ◽

Vol 18 (4) ◽

pp. 455-466

Author(s):

Yoon,Chung-Su ◽

한윤선 ◽

박대령 ◽

하태균

Keyword(s):

Skeletal Muscle ◽

Cytochrome C ◽

Acute Exercise ◽

Hsp 70 ◽

Rat Skeletal Muscle ◽

Hsp 27 ◽

Αb Crystallin

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Expression and cellular localization of glucose transporters (GLUT1, GLUT3, GLUT4) during differentiation of myogenic cells isolated from rat foetuses

Journal of Cell Science ◽

10.1242/jcs.107.3.487 ◽

1994 ◽

Vol 107 (3) ◽

pp. 487-496 ◽

Cited By ~ 3

Author(s):

I. Guillet-Deniau ◽

A. Leturque ◽

J. Girard

Keyword(s):

Skeletal Muscle ◽

Plasma Membrane ◽

Glucose Transport ◽

Cell Fusion ◽

Cellular Localization ◽

Glucose Transporter ◽

Glucose Transporters ◽

Short Exposure ◽

Myoblast Differentiation ◽

Igf I

Skeletal muscle regeneration is mediated by the proliferation of myoblasts from stem cells located beneath the basal lamina of myofibres, the muscle satellite cells. They are functionally indistinguishable from embryonic myoblasts. The myogenic process includes the fusion of myoblasts into multinucleated myotubes, the biosynthesis of proteins specific for skeletal muscle and proteins that regulates glucose metabolism, the glucose transporters. We find that three isoforms of glucose transporter are expressed during foetal myoblast differentiation: GLUT1, GLUT3 and GLUT4; their relative expression being dependent upon the stage of differentiation of the cells. GLUT1 mRNA and protein were abundant only in myoblasts from 19-day-old rat foetuses or from adult muscles. GLUT3 mRNA and protein, detectable in both cell types, increased markedly during cell fusion, but decreased in contracting myotubes. GLUT4 mRNA and protein were not expressed in myoblasts. They appeared only in spontaneously contracting myotubes cultured on an extracellular matrix. Insulin or IGF-I had no effect on the expression of the three glucose transporter isoforms, even in the absence of glucose. The rate of glucose transport, assessed using 2-[3H]deoxyglucose, was 2-fold higher in myotubes than in myoblasts. Glucose deprivation increased the basal rate of glucose transport by 2-fold in myoblasts, and 4-fold in myotubes. The cellular localization of the glucose transporters was directly examined by immunofluorescence staining. GLUT1 was located on the plasma membrane of myoblasts and myotubes. GLUT3 was located intracellularly in myoblasts and appeared also on the plasma membrane in myotubes. Insulin or IGF-I were unable to target GLUT3 to the plasma membrane. GLUT4, the insulin-regulatable glucose transporter isoform, appeared only in contracting myotubes in small intracellular vesicles. It was translocated to the plasma membrane after a short exposure to insulin, as it is in skeletal muscle in vivo. These results show that there is a switch in glucose transporter isoform expression during myogenic differentiation, dependent upon the energy required by the different stages of the process. GLUT3 seemed to play a role during cell fusion, and could be a marker for the muscle's ability to regenerate.

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Beta-adrenergic modulation of insulin binding in skeletal muscle

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1986.250.2.e198 ◽

1986 ◽

Vol 250 (2) ◽

pp. E198-E204

Author(s):

B. Webster ◽

S. R. Vigna ◽

T. Paquette ◽

D. J. Koerker

Keyword(s):

Skeletal Muscle ◽

Plasma Membrane ◽

Protein Phosphatase ◽

Adrenergic Receptors ◽

Plasma Membranes ◽

Acute Exercise ◽

Insulin Binding ◽

Beta Adrenergic Receptors ◽

Beta Adrenergic ◽

Adrenergic Antagonist

Both a high physiological concentration (13.1 nM) of epinephrine (E) and acute exercise (AEx) have previously been shown to increase 125I-insulin binding in skeletal muscle. To investigate the site and mechanism of the effect of epinephrine on binding and the possible link between epinephrine- and AEx-enhanced insulin binding, we measured insulin binding in three different preparations: 1) crude membranes derived from whole soleus muscle incubated in vitro with 13.1 nM E, 2) crude membranes with E present in the binding assay, and 3) purified plasma membranes with E present. Epinephrine enhanced binding in all three preparations by 169, 144, and 164%, respectively, at low concentrations of insulin but had little effect at high concentrations. Epinephrine, therefore appears to have its effect at the plasma membrane. Propranolol (10 microM), a beta-adrenergic antagonist, blocked E-enhanced insulin binding and when added to crude membranes made from soleus and extensor digitorum longus muscle of AEx rats reversed the increase in binding seen with exercise. This indicates that E-enhanced insulin binding is mediated by beta-adrenergic receptors and that AEx enhances insulin binding via beta-adrenergic receptors. Sodium orthovanadate (3 mM), a phosphotyrosyl-protein phosphatase inhibitor, also inhibited the increase in insulin binding due to E, implying that E may increase insulin binding by activating a phosphotyrosyl-protein phosphatase which decreases the phosphorylation of a plasma membrane protein, presumably the insulin receptor.

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Insulin increases the Na(+)-K(+)-ATPase alpha 2-subunit in the surface of rat skeletal muscle: morphological evidence

AJP Cell Physiology ◽

10.1152/ajpcell.1993.265.6.c1716 ◽

1993 ◽

Vol 265 (6) ◽

pp. C1716-C1722 ◽

Cited By ~ 57

Author(s):

A. Marette ◽

J. Krischer ◽

L. Lavoie ◽

C. Ackerley ◽

J. L. Carpentier ◽

...

Keyword(s):

Skeletal Muscle ◽

Plasma Membrane ◽

Cellular Localization ◽

Protein A ◽

Morphological Evidence ◽

Mammalian Skeletal Muscle ◽

Tissue Fixation ◽

Insulin Stimulation ◽

Rat Skeletal Muscle ◽

Quantitative Evidence

The cellular localization of the alpha 2-subunit of the Na(+)-K(+)-ATPase was defined by immunoelectron microscopy, and the effect of insulin on the amount of alpha 2-immunoreactive subunits on the cell surface was quantitated. Two protocols were used for tissue fixation and immunolocalization. Protocol 1 was characterized by fixation with 2% paraformaldehyde, use of a monoclonal antibody, and detection with 3-nm-diameter gold-labeled Fab fragments or 10-nm gold-labeled immunoglobulin G. Protocol 2 was characterized by fixation with 4% paraformaldehyde plus 0.1% glutaraldehyde, use of a polyclonal antibody, and detection with 10-nm gold-labeled protein A. In control muscle, the alpha 2-subunit of the Na(+)-K(+)-ATPase was present at the plasma membrane and in intracellular tubular and vesicular structures located in subsarcolemmal and triadic regions. Acute insulin stimulation increased the number of immunolabeled alpha 2-subunits in the plasma membrane after both fixation protocols. The gain in the plasma membrane ranged from 1.5- to 3.7-fold and was significant at the level of P < 0.005. These results provide morphological quantitative evidence that the alpha 2-subunit of the Na(+)-K(+)-ATPase is present both at the plasma membrane and intracellularly in mammalian skeletal muscle and that insulin acutely increases its abundance in the muscle surface.

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