Propranolol prevents epinephrine from limiting insulin-stimulated muscle glucose uptake during contraction

2002 ◽  
Vol 93 (2) ◽  
pp. 697-704 ◽  
Author(s):  
Desmond G. Hunt ◽  
Zhenping Ding ◽  
John L. Ivy
Keyword(s):  
Insulin Receptor ◽  
Glucose Uptake ◽  
Kinase Activity ◽  
Pi3 Kinase ◽  
Insulin Receptor Substrate ◽  
Muscle Preparation ◽  
Acute Effects ◽  
Glucose Clearance ◽  
Slow Twitch ◽  
Isolated Rat

β-Blockade results in rapid glucose clearance and premature fatigue during exercise. To investigate the cause of this increased glucose clearance, we studied the acute effects of propranolol on insulin-stimulated muscle glucose uptake during contraction in the presence of epinephrine with an isolated rat muscle preparation. Glucose uptake increased in both fast- (epitrochlearis) and slow-twitch (soleus) muscle during insulin or contraction stimulation. In the presence of 24 nM epinephrine, glucose uptake during contraction was completely suppressed when insulin was present. This suppression of glucose uptake by epinephrine was accompanied by a decrease in insulin receptor substrate (IRS)-1-phosphatidylinositol 3 (PI3)-kinase activity. Propranolol had no direct effect on insulin-stimulated glucose uptake during contraction. However, epinephrine was ineffective in attenuating insulin-stimulated glucose uptake during contraction in the presence of propranolol. This ineffectiveness of epinephrine to suppress insulin-stimulated glucose uptake during contraction occurred in conjunction with its inability to completely suppress IRS-1-PI3-kinase activity. Results of this study indicate that the effectiveness of epinephrine to inhibit insulin-stimulated glucose uptake during contraction is severely diminished in muscle exposed to propranolol. Thus the increase in glucose clearance and premature fatigue associated with β-blockade could result from the inability of epinephrine to attenuate insulin-stimulated muscle glucose uptake.

Clenbuterol prevents epinephrine from antagonizing insulin-stimulated muscle glucose uptake

2002 ◽  
Vol 92 (3) ◽  
pp. 1285-1292 ◽  
Author(s):  
Desmond G. Hunt ◽  
Zhenping Ding ◽  
John L. Ivy
Keyword(s):  
Glucose Uptake ◽  
Kinase Activity ◽  
Pi3 Kinase ◽  
Intracellular Concentration ◽  
Insulin Receptor Substrate ◽  
Phosphatidylinositol 3 Kinase ◽  
Rat Skeletal Muscle ◽  
Slow Twitch ◽  
Chronic Clenbuterol ◽  
Fast Twitch

In the present study, we investigated the effects of chronic clenbuterol treatment on insulin-stimulated glucose uptake in the presence of epinephrine in isolated rat skeletal muscle. Insulin (50 μU/ml) increased glucose uptake in both fast-twitch (epitrochlearis) and slow-twitch (soleus) muscles. In the presence of 24 nM epinephrine, insulin-stimulated glucose uptake was completely suppressed. This suppression of glucose uptake by epinephrine was accompanied by an increase in the intracellular concentration of glucose 6-phosphate and a decrease in insulin-receptor substrate-1-associated phosphatidylinositol 3-kinase (IRS-1/PI3-kinase) activity. Clenbuterol treatment had no direct effect on insulin-stimulated glucose uptake. However, after clenbuterol treatment, epinephrine was ineffective in attenuating insulin-stimulated muscle glucose uptake. This ineffectiveness of epinephrine to suppress insulin-stimulated glucose uptake occurred in conjunction with its inability to increase the intracellular concentration of glucose 6-phosphate and attenuate IRS-1/PI3-kinase activity. Results of this study indicate that the effectiveness of epinephrine to inhibit insulin-stimulated glucose uptake is severely diminished in muscle from rats pretreated with clenbuterol.

scholarly journals Insulin receptor substrate 1 is phosphorylated by the serine kinase activity of phosphatidylinositol 3-kinase

1994 ◽  
Vol 304 (1) ◽  
pp. 17-21 ◽  
Author(s):  
J F Tanti ◽  
T Grémeaux ◽  
E Van Obberghen ◽  
Y Le Marchand-Brustel
Keyword(s):  
Insulin Receptor ◽  
Kinase Activity ◽  
Pi3 Kinase ◽  
Serine Phosphorylation ◽  
Kinase Assay ◽  
Insulin Receptor Substrate ◽  
Phosphatidylinositol 3 Kinase ◽  
Serine Kinase ◽  
Phosphatidylinositol 3

Insulin receptor substrate (IRS) 1, which is tyrosine phosphorylated in response to insulin, presents multiple serine/threonine phosphorylation sites. To search for a serine kinase activity towards IRS 1, immunoprecipitates from basal or stimulated 3T3-L1 adipocytes were used in an in vitro kinase assay. When IRS 1 was isolated from insulin-treated cells, serine phosphorylation of IRS 1 occurred, which we attribute to the kinase activity of the phosphatidylinositol 3-kinase (PI3-kinase). Importantly, in an in vitro reconstitution assay, an excess of the PI3-kinase subunit prevents this phosphorylation. Together, our results suggest that following insulin stimulation, PI3-kinase associates with IRS 1, allowing for its serine phosphorylation. This phosphorylation event could play a role in the modulation of insulin signalling.

scholarly journals NF-κB-Inducing Kinase (NIK) Mediates Skeletal Muscle Insulin Resistance: Blockade by Adiponectin

Endocrinology ◽  
2011 ◽  
Vol 152 (10) ◽  
pp. 3622-3627 ◽  
Author(s):  
Sanjeev Choudhary ◽  
Sandeep Sinha ◽  
Yanhua Zhao ◽  
Srijita Banerjee ◽  
Padma Sathyanarayana ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Skeletal Muscle ◽  
Glucose Uptake ◽  
Kinase Activity ◽  
Pi3 Kinase ◽  
Dominant Negative ◽  
Muscle Insulin Resistance ◽  
Akt Phosphorylation ◽  
Skeletal Muscle Insulin Resistance ◽  
Obese Subjects

Enhanced levels of nuclear factor (NF)-κB-inducing kinase (NIK), an upstream kinase in the NF-κB pathway, have been implicated in the pathogenesis of chronic inflammation in diabetes. We investigated whether increased levels of NIK could induce skeletal muscle insulin resistance. Six obese subjects with metabolic syndrome underwent skeletal muscle biopsies before and six months after gastric bypass surgery to quantitate NIK protein levels. L6 skeletal myotubes, transfected with NIK wild-type or NIK kinase-dead dominant negative plasmids, were treated with insulin alone or with adiponectin and insulin. Effects of NIK overexpression on insulin-stimulated glucose uptake were estimated using tritiated 2-deoxyglucose uptake. NF-κB activation (EMSA), phosphatidylinositol 3 (PI3) kinase activity, and phosphorylation of inhibitor κB kinase β and serine-threonine kinase (Akt) were measured. After weight loss, skeletal muscle NIK protein was significantly reduced in association with increased plasma adiponectin and enhanced AMP kinase phosphorylation and insulin sensitivity in obese subjects. Enhanced NIK expression in cultured L6 myotubes induced a dose-dependent decrease in insulin-stimulated glucose uptake. The decrease in insulin-stimulated glucose uptake was associated with a significant decrease in PI3 kinase activity and protein kinase B/Akt phosphorylation. Overexpression of NIK kinase-dead dominant negative did not affect insulin-stimulated glucose uptake. Adiponectin treatment inhibited NIK-induced NF-κB activation and restored insulin sensitivity by restoring PI3 kinase activation and subsequent Akt phosphorylation. These results indicate that NIK induces insulin resistance and further indicate that adiponectin exerts its insulin-sensitizing effect by suppressing NIK-induced skeletal muscle inflammation. These observations suggest that NIK could be an important therapeutic target for the treatment of insulin resistance associated with inflammation in obesity and type 2 diabetes.

scholarly journals Losartan counteracts the effects of cardiomyocyte swelling on glucose uptake and insulin receptor substrate-1 levels

Peptides ◽  
2017 ◽  
Vol 96 ◽  
pp. 38-43
Author(s):  
Yamil Gerena ◽  
Janice Griselle Lozada ◽  
Bryan Jael Collazo ◽  
Jarold Méndez-Álvarez ◽  
Jennifer Méndez-Estrada ◽  
...  
Keyword(s):  
Insulin Receptor ◽  
Glucose Uptake ◽  
Insulin Receptor Substrate ◽  
Insulin Receptor Substrate 1

scholarly journals Vanadate fully stimulates insulin receptor substrate-1 associated phosphatidyl inositol 3-kinase activity in adipocytes from young and old rats

FEBS Letters ◽  
1998 ◽  
Vol 425 (2) ◽  
pp. 298-304 ◽  
Author(s):  
Juan C Molero ◽  
Carmen Martı́nez ◽  
Antonio Andrés ◽  
Jorgina Satrústegui ◽  
José M Carrascosa
Keyword(s):  
Insulin Receptor ◽  
Kinase Activity ◽  
Phosphatidyl Inositol ◽  
Insulin Receptor Substrate ◽  
Insulin Receptor Substrate 1 ◽  
Old Rats

scholarly journals Essential Role of Insulin Receptor Substrate-2 in Insulin Stimulation of Glut4 Translocation and Glucose Uptake in Brown Adipocytes

2000 ◽  
Vol 275 (33) ◽  
pp. 25494-25501 ◽  
Author(s):  
Mathias Fasshauer ◽  
Johannes Klein ◽  
Kohjiro Ueki ◽  
Kristina M. Kriauciunas ◽  
Manuel Benito ◽  
...  
Keyword(s):  
Insulin Receptor ◽  
Glucose Uptake ◽  
Essential Role ◽  
Insulin Receptor Substrate ◽  
Glut4 Translocation ◽  
Insulin Stimulation ◽  
Brown Adipocytes ◽  
Stimulation Of

scholarly journals Phosphatidylinositol 3-kinase acts at an intracellular membrane site to enhance GLUT4 exocytosis in 3T3-L1 cells

1996 ◽  
Vol 313 (1) ◽  
pp. 125-131 ◽  
Author(s):  
Jing YANG ◽  
James F. CLARKE ◽  
Catriona J. ESTER ◽  
Paul W. YOUNG ◽  
Masato KASUGA ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Insulin Receptor ◽  
Time Course ◽  
Glucose Transporter ◽  
Kinase Activity ◽  
Insulin Receptor Substrate ◽  
Low Density ◽  
Intracellular Membrane ◽  
Phosphatidylinositol 3 Kinase ◽  
Phosphatidylinositol 3

Glucose transporters (GLUTs) are continuously recycled in 3T3-L1 cells and so insulin, through its action on phosphatidylinositol 3-kinase (PI 3-kinase), could potentially alter the distribution of these transporters by enhancing retention in the plasma membrane or acting intracellularly to increase exocytosis, either by stimulating a budding or a docking and fusion process. To examine the site of involvement of PI 3-kinase in the glucose transporter recycling pathway, we have determined the kinetics of recycling under conditions in which the PI 3-kinase activity is inhibited by wortmannin. Wortmannin addition to fully insulin-stimulated cells induces a net reduction of glucose transport activity with a time course that is consistent with a major effect on the return of internalized transporters to the plasma membrane. The exocytosis of GLUT1 and GLUT4 is reduced to very low levels in wortmannin-treated cells (≈ 0.009 min-1), but the endocytosis of these isoforms is not markedly perturbed and the rate constants are approx. 10-fold higher than for exocytosis (0.099 and 0.165 min-1, respectively). The slow reduction in basal activity following treatment with wortmannin is consistent with a wortmannin effect on constitutive recycling as well as insulin-regulated exocytosis. PI 3-kinase activity that is precipitated by anti-phosphotyrosine, anti-[insulin receptor substrate 1 (IRS1)] and anti-α-p85 antibodies show the same level of insulin-stimulated activity, ≈ 0.5 pmol/20 min per dish of 3T3-L1 cells. Since the activities precipitated by all three antibodies are similar, it seems unlikely that a second insulin receptor substrate, IRS2, contributes significantly to the insulin signalling observed in 3T3-L1 cells. To examine whether insulin targets PI 3-kinase to intracellular membranes we have carried out subcellular fractionation studies. These suggest that nearly all the insulin-stimulated PI 3-kinase activity is located on intracellular, low-density, membranes. In addition, the association of PI 3-kinase with IRS1 appears to partially deplete the cytoplasm of α-p85-precipitatable activity, suggesting that IRS1 may redistribute PI 3-kinase from the cytoplasm to the low-density microsome membranes. Taken together, the trafficking kinetic and PI 3-kinase distribution studies suggest an intracellular membrane site of action of the enzyme in enhancing glucose transporter exocytosis.

scholarly journals Nutrients Suppress Phosphatidylinositol 3-Kinase/Akt Signaling via Raptor-Dependent mTOR-Mediated Insulin Receptor Substrate 1 Phosphorylation

2006 ◽  
Vol 26 (1) ◽  
pp. 63-76 ◽  
Author(s):  
Alexandros Tzatsos ◽  
Konstantin V. Kandror
Keyword(s):  
Insulin Receptor ◽  
Mammalian Target Of Rapamycin ◽  
Insulin Dependent Diabetes Mellitus ◽  
Akt Signaling ◽  
Pi3 Kinase ◽  
Dependent Diabetes Mellitus ◽  
Insulin Receptor Substrate ◽  
Insulin Receptor Substrate 1 ◽  
Insulin Dependent ◽  
Phosphatidylinositol 3

ABSTRACT Nutritional excess and/or obesity represent well-known predisposition factors for the development of non-insulin-dependent diabetes mellitus (NIDDM). However, molecular links between obesity and NIDDM are only beginning to emerge. Here, we demonstrate that nutrients suppress phosphatidylinositol 3 (PI3)-kinase/Akt signaling via Raptor-dependent mTOR (mammalian target of rapamycin)-mediated phosphorylation of insulin receptor substrate 1 (IRS-1). Raptor directly binds to and serves as a scaffold for mTOR-mediated phosphorylation of IRS-1 on Ser636/639. These serines lie close to the Y632MPM motif that is implicated in the binding of p85α/p110α PI3-kinase to IRS-1 upon insulin stimulation. Phosphomimicking mutations of these serines block insulin-stimulated activation of IRS-1-associated PI3-kinase. Knockdown of Raptor as well as activators of the LKB1/AMPK pathway, such as the widely used antidiabetic compound metformin, suppress IRS-1 Ser636/639 phosphorylation and reverse mTOR-mediated inhibition on PI3-kinase/Akt signaling. Thus, diabetes-related hyperglycemia hyperactivates the mTOR pathway and may lead to insulin resistance due to suppression of IRS-1-dependent PI3-kinase/Akt signaling.

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