Abnormal glucose transport and GLUT1 cell-surface content in fibroblasts and skeletal muscle from NIDDM and obese subjects

Skeletal muscle glucose transport was examined in transgenic mice overexpressing the glucose transporter GLUT1 using both the isolated incubated-muscle preparation and the hind-limb perfusion technique. In the absence of insulin, 2-deoxy-d-glucose uptake was increased ∼ 3–8-fold in isolated fast-twitch muscles of GLUT1 transgenic mice compared with non-transgenic siblings. Similarly, basal glucose transport activity was increased ∼ 4–14-fold in perfused fast-twitch muscles of transgenic mice. In non-transgenic mice insulin accelerated glucose transport activity ∼ 2–3-fold in isolated muscles and to a much greater extent (∼ 7–20-fold) in perfused hind-limb preparations. The observed effect of insulin on glucose transport in transgenic muscle was similarly dependent upon the technique used for measurement, as insulin had no effect on isolated fast-twitch muscle from transgenic mice, but significantly enhanced glucose transport in perfused fast-twitch muscle from transgenic mice to ∼ 50–75% of the magnitude of the increase observed in non-transgenic mice. Cell-surface glucose transporter content was assessed via 2-N-4-(l-azi-2,2,2-trifluoroethyl)benzoyl-1,3-bis-(d -mannos-4-yloxy)-2-propylamine photolabelling methodology in both isolated and perfused extensor digitorum longus (EDL). Cell-surface GLUT1 was enhanced by as much as 70-fold in both isolated and perfused EDL of transgenic mice. Insulin did not alter cell-surface GLUT1 in either transgenic or non-transgenic mice. Basal levels of cell-surface GLUT4, measured in either isolated or perfused EDL, were similar in transgenic and non-transgenic mice. Interestingly, insulin enhanced cell-surface GLUT4 ∼ 2-fold in isolated EDL and ∼ 6-fold in perfused EDL of both transgenic and non-transgenic mice. In summary, these results reveal differences between isolated muscle and perfused hind-limb techniques, with the latter method showing a more robust responsiveness to insulin. Furthermore, the results demonstrate that muscle overexpressing GLUT1 has normal insulin-induced GLUT4 translocation and the ability to augment glucose-transport activity above the elevated basal rates.

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Analysis of insulin-stimulated insulin receptor activation and glucose transport in cultured skeletal muscle cells from obese subjects

Metabolism ◽

10.1016/j.metabol.2004.11.018 ◽

2005 ◽

Vol 54 (5) ◽

pp. 598-603 ◽

Cited By ~ 13

Author(s):

Celia Pender ◽

Ira D. Goldfine ◽

Jennifer L. Kulp ◽

Charles J. Tanner ◽

Betty A. Maddux ◽

...

Keyword(s):

Skeletal Muscle ◽

Insulin Receptor ◽

Glucose Transport ◽

Muscle Cells ◽

Receptor Activation ◽

Skeletal Muscle Cells ◽

Obese Subjects

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Exercise Restores Skeletal Muscle Glucose Delivery But Not Insulin-Mediated Glucose Transport and Phosphorylation in Obese Subjects

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2006-0269 ◽

2006 ◽

Vol 91 (9) ◽

pp. 3394-3403 ◽

Cited By ~ 7

Author(s):

L. Slimani ◽

V. Oikonen ◽

K. Hällsten ◽

N. Savisto ◽

J. Knuuti ◽

...

Keyword(s):

Skeletal Muscle ◽

Positron Emission Tomography ◽

Glucose Transport ◽

Oxidative Capacity ◽

Emission Tomography ◽

Glucose Disposal ◽

Oxidative Potential ◽

Positron Emission ◽

Significant Difference ◽

Obese Subjects

Abstract Context/Objective: Insulin resistance in obese subjects results in the impaired disposal of glucose by skeletal muscle. The current study examined the effects of insulin and/or exercise on glucose transport and phosphorylation in skeletal muscle and the influence of obesity on these processes. Subjects/Methods: Seven obese and 12 lean men underwent positron emission tomography with 2-deoxy-2-[18F]fluoro-d-glucose in resting and isometrically exercising skeletal muscle during normoglycemic hyperinsulinemia. Data were analyzed by two-tissue compartmental modeling. Perfusion and oxidative capacity were measured during insulin stimulation by [15O]H2O and [15O]O2. Results: Exercise increased glucose fractional uptake (K), inward transport rate (K1), and the k3 parameter, combining transport and intracellular phosphorylation, in lean and obese subjects. In each group, there was no statistically significant difference between plasma flow and K1. At rest, a significant defect in K1 (P = 0.0016), k3 (P = 0.016), and K (P = 0.022) was found in obese subjects. Exercise restored K1, improved but did not normalize K (P = 0.03 vs. lean), and did not ameliorate the more than 60% relative impairment in k3 in obese individuals (P = 0.002 vs. lean). The glucose oxidative potential tended to be reduced by obesity. Conclusions/Interpretation: The study indicates that exercise restores the impairment in insulin-mediated skeletal muscle perfusion and glucose delivery associated with obesity but does not normalize the defect involving the proximal steps regulating glucose disposal in obese individuals. Our data support the use of 2-deoxy-2-[18F]fluoro-d-glucose-positron emission tomography in the dissection between substrate supply and intrinsic tissue metabolism.

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Insulin stimulation of glucose transport activity in rat skeletal muscle: increase in cell surface GLUT4 as assessed by photolabelling

Biochemical Journal ◽

10.1042/bj2990755 ◽

1994 ◽

Vol 299 (3) ◽

pp. 755-759 ◽

Cited By ~ 56

Author(s):

C M Wilson ◽

S W Cushman

Keyword(s):

Skeletal Muscle ◽

Cell Surface ◽

Glucose Transport ◽

Fold Increase ◽

Transport Activity ◽

Insulin Stimulation ◽

Rat Skeletal Muscle ◽

Photoaffinity Label ◽

Isolated Rat ◽

Stimulation Of

We have used a photoaffinity label to quantify cell surface GLUT4 glucose transporters in isolated rat soleus muscles. In this system, insulin stimulated an 8.6-fold increase in 3-O-methylglucose glucose transport, while photolabelled GLUT4 increased 8-fold. These results demonstrate that the insulin-stimulated increase in glucose transport activity in skeletal muscle can be accounted for by an increase in surface-accessible GLUT4 content.

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Regulation of cell surface GLUT4 in skeletal muscle of transgenic mice

Biochemical Journal ◽

10.1042/bj3210075 ◽

1997 ◽

Vol 321 (1) ◽

pp. 75-81 ◽

Cited By ~ 17

Author(s):

Joseph T. BROZINICK ◽

Scott C. McCOID ◽

Thomas H. REYNOLDS ◽

Cindy M. WILSON ◽

Ralph W. STEVENSON ◽

...

Keyword(s):

Skeletal Muscle ◽

Cell Surface ◽

Glucose Transport ◽

Glucose Transporter ◽

Subcellular Fractionation ◽

Muscle Membrane ◽

Transport Activity ◽

Hindlimb Muscles ◽

Subcellular Membrane ◽

Glucose Transporter Glut4

Marked overexpression of the glucose transporter GLUT4 in skeletal muscle membrane fractions of GLUT4 transgenic (TG) mice is accompanied by disproportionately small increases in basal and insulin-stimulated glucose transport activity. Thus we have assessed cell surface GLUT4 by photolabelling with the membrane-impermeant reagent 2-N-[4-(1-azi-2,2,2-trifluoroethyl)benzoyl]-1,3-bis(d-mannos-4-yloxy)-2-propylamine (ATB-BMPA) and measured the corresponding glucose transport activity using 2-deoxyglucose in isolated extensor digitorum longus (EDL) muscles from non-transgenic (NTG) and GLUT4 TG mice in the absence and presence of 13.3 nM (2000 µ-units/ml) insulin, without or with hypoxia as a model of muscle contraction. TG mice displayed elevated rates of glucose transport activity under basal and insulin-stimulated conditions, and in the presence of insulin plus hypoxia, compared with NTG mice. Photoaffinity labelling of cell surface GLUT4 indicated corresponding elevations in plasma membrane GLUT4 in the basal and insulin-stimulated states, and with insulin plus hypoxia, but no difference in cell surface GLUT4 during hypoxia stimulation. Subcellular fractionation of hindlimb muscles confirmed the previously observed 3-fold overexpression of GLUT4 in the TG compared with the NTG mice. These results suggest that: (1) alterations in glucose transport activity which occur with GLUT4 overexpression in EDL muscles are directly related to cell surface GLUT4 content, regardless of the levels observed in the corresponding subcellular membrane fractions, (2) while overexpression of GLUT4 influences both basal and insulin-stimulated glucose transport activity, the response to hypoxia/contraction-stimulated glucose transport is unchanged, and (3) subcellular fractionation provides little insight into the subcellular trafficking of GLUT4, and whatever relationship is demonstrated in EDL muscles from NTG mice is disrupted on GLUT4 overexpression.

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Glucose transport and cell surface GLUT-4 protein in skeletal muscle of the obese Zucker rat

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1996.271.2.e294 ◽

1996 ◽

Vol 271 (2) ◽

pp. E294-E301 ◽

Cited By ~ 37

Author(s):

G. J. Etgen ◽

C. M. Wilson ◽

J. Jensen ◽

S. W. Cushman ◽

J. L. Ivy

Keyword(s):

Skeletal Muscle ◽

Cell Surface ◽

Glucose Transport ◽

Zucker Rats ◽

Zucker Rat ◽

Glut 4 ◽

Obese Zucker Rat ◽

Obese Rats ◽

Slow Twitch ◽

Fast Twitch

The relationship between 3-O-methyl-D-glucose transport and 2-N-4-(1-azi-2,2,2-trifluoroethyl)-benzoyl-1, 3-bis-(D-mannos-4-yloxy)-2-propylamine (ATB-BMPA)-labeled cell surface GLUT-4 protein was assessed in fast-twitch (epitrochlearis) and slow-twitch (soleus) muscles of lean and obese (fa/fa) Zucker rats. In the absence of insulin, glucose transport as well as cell surface GLUT-4 protein was similar in both epitrochlearis and soleus muscles of lean and obese rats. In contrast, insulin-stimulated glucose transport rates were significantly higher for lean than obese rats in both soleus (0.74 +/- 0.05 vs. 0.40 +/- 0.02 mumol.g-1.10 min-1) and epitrochlearis (0.51 +/- 0.05 vs. 0.17 +/- 0.02 mumol.g-1.10 min-1) muscles. The ability of insulin to enhance glucose transport in fast- and slow-twitch muscles from both lean and obese rats corresponded directly with changes in cell surface GLUT-4 protein. Muscle contraction elicited similar increases in glucose transport in lean and obese rats, with the effect being more pronounced in fast-twitch (0.70 +/- 0.07 and 0.77 +/- 0.04 mumol.g-1.10 min-1 for obese and lean, respectively) than in slow-twitch muscle (0.36 +/- 0.03 and 0.40 +/- 0.02 mumol.g-1.10 min-1 for obese and lean, respectively). The contraction-induced changes in glucose transport directly corresponded with the observed changes in cell surface GLUT-4 protein. Thus the reduced glucose transport response to insulin in skeletal muscle of the obese Zucker rat appears to result directly from an inability to effectively enhance cell surface GLUT-4 protein.

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