Inhibition of glucose uptake in murine cardiomyocyte cell line HL-1 by cardioprotective drugs dilazep and dipyridamole

Inhibition of adenosine reuptake by nucleoside transport inhibitors, such as dipyridamole and dilazep, is proposed to increase extracellular levels of adenosine and thereby potentiate adenosine receptor-dependent pathways that promote cardiovascular health. Thus adenosine can act as a paracrine and/or autocrine hormone, which has been shown to regulate glucose uptake in some cell types. However, the role of adenosine in modulating glucose transport in cardiomyocytes is not clear. Therefore, we investigated whether exogenously applied adenosine or inhibition of adenosine transport by S-(4-nitrobenzyl)-6-thioinosine (NBTI), dipyridamole, or dilazep modulated basal and insulin-stimulated glucose uptake in the murine cardiomyocyte cell line HL-1. HL-1 cell lysates were subjected to SDS-PAGE and immunoblotting to determine which GLUT isoforms are present. Glucose uptake was measured in the presence of dipyridamole (3–300 μM), dilazep (1–100 μM), NBTI (10–500 nM), and adenosine (50–250 μM) or the nonmetabolizable adenosine analog 2-chloro-adenosine (250 μM). Our results demonstrated that HL-1 cells possess GLUT1 and GLUT4, the isoforms typically present in cardiomyocytes. We found no evidence for adenosine-dependent regulation of basal or insulin-stimulated glucose transport in HL-1 cardiomyocytes. However, we did observe a dose-dependent inhibition of glucose transport by dipyridamole (basal, IC50= 12.2 μM, insulin stimulated, IC50= 13.09 μM) and dilazep (basal, IC50= 5.7 μM, insulin stimulated, IC50= 19 μM) but not NBTI. Thus our data suggest that dipyridamole and dilazep, which are widely used to specifically inhibit nucleoside transport, have a broader spectrum of transport inhibition than previously described. Moreover, these data may explain previous observations, in which dipyridamole was noted to be proischemic at high doses.

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Inhibition of insulin-stimulated glucose transport in rat adipocytes by nucleoside transport inhibitors

FEBS Letters ◽

10.1016/0014-5793(88)80901-3 ◽

1988 ◽

Vol 227 (2) ◽

pp. 215-219 ◽

Cited By ~ 12

Author(s):

H.J. Steinfelder ◽

H.G. Joost

Keyword(s):

Glucose Transport ◽

Nucleoside Transport ◽

Rat Adipocytes ◽

Nucleoside Transport Inhibitors ◽

Transport Inhibitors

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Enantiomeric selectivity of adenosine transport systems in mouse erythrocytes and L1210 cells

Biochemical Journal ◽

10.1042/bj2630957 ◽

1989 ◽

Vol 263 (3) ◽

pp. 957-960 ◽

Cited By ~ 24

Author(s):

W P Gati ◽

L Dagnino ◽

A R P Paterson

Keyword(s):

Cell Types ◽

Mirror Image ◽

Nucleoside Transport ◽

Transport Systems ◽

Simple Diffusion ◽

L1210 Cells ◽

Marked Preference ◽

Adenosine Transport ◽

Mouse Leukaemia ◽

Enantiomeric Selectivity

In mediating the entry of adenosine into mouse erythrocytes and mouse leukaemia L1210 cells, nucleoside transport systems were stereoselective, showing a marked preference for the D-enantiomer of adenosine (D-Ado). Inward zero-trans fluxes of the mirror-image isomer, L-adenosine (L-Ado), in those cells were slow relative to those of D-Ado. Contributing to L-Ado fluxes in both cell types were (i) a transporter-mediated process of high nitrobenzylthioinosine-sensitivity and (ii) simple diffusion.

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Steviol Glycosides Modulate Glucose Transport in Different Cell Types

Oxidative Medicine and Cellular Longevity ◽

10.1155/2013/348169 ◽

2013 ◽

Vol 2013 ◽

pp. 1-11 ◽

Cited By ~ 31

Author(s):

Benedetta Rizzo ◽

Laura Zambonin ◽

Cristina Angeloni ◽

Emanuela Leoncini ◽

Francesco Vieceli Dalla Sega ◽

...

Keyword(s):

Glucose Uptake ◽

Glucose Transport ◽

Molecular Mechanisms ◽

Neuroblastoma Cells ◽

Stevia Rebaudiana ◽

Cell Types ◽

Akt Pathway ◽

Steviol Glycosides ◽

Human Neuroblastoma

Extracts fromStevia rebaudianaBertoni, a plant native to Central and South America, have been used as a sweetener since ancient times. Currently,Steviaextracts are largely used as a noncaloric high-potency biosweetener alternative to sugar, due to the growing incidence of type 2 diabetes mellitus, obesity, and metabolic disorders worldwide. Despite the large number of studies onSteviaand steviol glycosidesin vivo, little is reported concerning the cellular and molecular mechanisms underpinning the beneficial effects on human health. The effect of four commercialSteviaextracts on glucose transport activity was evaluated in HL-60 human leukaemia and in SH-SY5Y human neuroblastoma cells. The extracts were able to enhance glucose uptake in both cellular lines, as efficiently as insulin. Our data suggest that steviol glycosides could act by modulating GLUT translocation through the PI3K/Akt pathway since treatments with both insulin andSteviaextracts increased the phosphorylation of PI3K and Akt. Furthermore,Steviaextracts were able to revert the effect of the reduction of glucose uptake caused by methylglyoxal, an inhibitor of the insulin receptor/PI3K/Akt pathway. These results corroborate the hypothesis thatSteviaextracts could mimic insulin effects modulating PI3K/Akt pathway.

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Apoptosis is regulated by the rate of glucose transport in an interleukin 3 dependent cell line.

Journal of Experimental Medicine ◽

10.1084/jem.180.3.917 ◽

1994 ◽

Vol 180 (3) ◽

pp. 917-923 ◽

Cited By ~ 81

Author(s):

O Kan ◽

S A Baldwin ◽

A D Whetton

Keyword(s):

Growth Factor ◽

Tyrosine Kinase ◽

Glucose Uptake ◽

Cell Line ◽

Glucose Transport ◽

Alternative Energy ◽

Protein Tyrosine Kinase ◽

Permissive Temperature ◽

Interleukin 3 ◽

Abl Tyrosine Kinase

In the absence of a survival stimulus, the interleukin 3 (IL-3)-dependent IC.DP cell line undergoes a process termed programmed cell death or apoptosis. Survival can be induced by IL-3, which can also stimulate proliferation of IC.DP cells. IC.DP cells have been stably transfected with the p160v-abl protein tyrosine kinase, activation of the kinase at the permissive temperature permits cell survival in the absence of IL-3 by suppression of apoptosis, although the growth factor is still required for proliferation. Both IL-3 and activation of the v-ABL tyrosine kinase stimulated glucose transport, which may in part be due to a translocation of transporters to the cell surface. Inhibition of glucose uptake markedly increased the rate of apoptosis in these cells, an effect that could be reversed by the provision of alternative energy sources such as glutamine. Growth factor- or oncogene-mediated increases in glucose uptake may therefore represent an important regulatory point in the suppression of apoptosis.

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Dissection of stress-activated glucose transport from insulin-induced glucose transport in mammalian cells using wortmannin and ML-9

Biochemical Journal ◽

10.1042/bj3090731 ◽

1995 ◽

Vol 309 (3) ◽

pp. 731-736 ◽

Cited By ~ 17

Author(s):

L F Barros ◽

R B Marchant ◽

S A Baldwin

Keyword(s):

Glucose Uptake ◽

Glucose Transport ◽

Mammalian Cells ◽

Kinase Inhibitor ◽

Metabolic Stress ◽

Cell Types ◽

Mitogen Activated Protein Kinase ◽

Uptake Capacity ◽

Mitogen Activated Protein ◽

Stimulation Of

The signaling pathways responsible for the activation of glucose transport by insulin and by metabolic stress in mammalian cells were studied in Clone 9 cells and 3T3-L1 adipocytes. Exposure of both cell types to azide or insulin markedly increased their glucose uptake capacity (Vmax.) without affecting their apparent affinity for glucose (Km). The effects of azide and insulin were not additive. Wortmannin, a selective inhibitor of phosphatidylinositol (PI) 3-kinase, did not affect stimulation of transport by azide but inhibited insulin-induced glucose transport with a Ki of < 10 nM. ML-9, a putative mitogen-activated protein kinase inhibitor, was equipotent in its inhibition of azide- and insulin-stimulated glucose transport. These findings suggest that multiple signalling cascades are involved in the stimulation of glucose transport in mammalian cells and that PI 3-kinase, an essential link in the pathway by which insulin stimulates glucose transport, is not necessary for the activation of glucose uptake by metabolic stress.

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Hypoxanthine enters human vascular endothelial cells (ECV 304) via the nitrobenzylthioinosine-insensitive equilibrative nucleoside transporter

Biochemical Journal ◽

10.1042/bj3170843 ◽

1996 ◽

Vol 317 (3) ◽

pp. 843-848 ◽

Cited By ~ 37

Author(s):

Nelson OSSES ◽

Jeremy D. PEARSON ◽

David L. YUDILEVICH ◽

Simon M. JARVIS

Keyword(s):

Endothelial Cells ◽

Vascular Endothelial Cells ◽

Umbilical Vein ◽

Nucleoside Transport ◽

Vascular Endothelial ◽

Nucleoside Transporter ◽

Equilibrative Nucleoside Transporter ◽

Nucleoside Transport Inhibitors ◽

Adenosine Transport ◽

Transport Inhibitors

The transport properties of the nucleobase hypoxanthine were examined in the human umbilical vein endothelial cell line ECV 304. Initial rates of hypoxanthine influx were independent of extracellular cations: replacement of Na+ with Li+, Rb+, N-methyl-d-glucamine or choline had no significant effect on hypoxanthine uptake by ECV 304 cells. Kinetic analysis demonstrated the presence of a single saturable system for the transport of hypoxanthine in ECV 304 cells with an apparent Km of 320±10 μM and a Vmax of 5.6±0.9 pmol/106 cells per s. Hypoxanthine uptake was inhibited by the nucleosides adenosine, uridine and thymidine (apparent Ki 41±6, 240±27 and 59±8 μM respectively) and the nucleoside transport inhibitors nitrobenzylthioinosine (NBMPR), dilazep and dipyridamole (apparent Ki 2.5±0.3, 11±3 and 0.16±0.006 μM respectively), whereas the nucleobases adenine, guanine and thymine had little effect (50% inhibition at > 1 mM). ECV 304 cells were also shown to transport adenosine via both the NBMPR-sensitive and -insensitive nucleoside carriers. Hypoxanthine specifically inhibited adenosine transport via the NBMPR-insensitive system in a competitive manner (apparent Ki 290±14 μM). These results indicate that hypoxanthine entry into ECV 304 endothelial cells is mediated by the NBMPR-insensitive nucleoside carrier present in these cells.

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Akt inhibitors reduce glucose uptake independently of their effects on Akt

Biochemical Journal ◽

10.1042/bj20100750 ◽

2010 ◽

Vol 432 (1) ◽

pp. 191-198 ◽

Cited By ~ 18

Author(s):

Shi-Xiong Tan ◽

Yvonne Ng ◽

David E. James

Keyword(s):

Plasma Membrane ◽

Glucose Uptake ◽

Glucose Transport ◽

Cell Types ◽

Signalling Pathway ◽

Whole Body ◽

Similar Reduction ◽

Cellular Processes ◽

Glucose Homoeostasis ◽

Protein Kinase Akt

The protein kinase Akt is involved in various cellular processes, including cell proliferation, growth and metabolism. Hyperactivation of Akt is commonly observed in human tumours and so this pathway has been the focus of targeted drug discovery. However, Akt also plays an essential role in other physiological processes, such as the insulin-regulated transport of glucose into muscle and fat cells. This process, which is essential for whole-body glucose homoeostasis in mammals, is thought to be mediated via Akt-dependent movement of GLUT4 glucose transporters to the plasma membrane. In the present study, we have investigated the metabolic side effects of non-ATP-competitive allosteric Akt inhibitors. In 3T3-L1 adipocytes, these inhibitors caused a decrease in the Akt signalling pathway concomitant with reduced glucose uptake. Surprisingly, a similar reduction in GLUT4 translocation to the plasma membrane was not observed. Further investigation revealed that the inhibitory effects of these compounds on glucose uptake in 3T3-L1 adipocytes were independent of the Akt signalling pathway. The inhibitors also inhibited glucose transport into other cell types, including human erythrocytes and T-47D breast cancer cells, suggesting that these effects are not specific to GLUT4. We conclude that these drugs may, at least in part, inhibit tumorigenesis through inhibition of tumour cell glucose transport.

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A GSK-3/TSC2/mTOR pathway regulates glucose uptake and GLUT1 glucose transporter expression

AJP Cell Physiology ◽

10.1152/ajpcell.00554.2007 ◽

2008 ◽

Vol 295 (3) ◽

pp. C836-C843 ◽

Cited By ~ 136

Author(s):

Carolyn L. Buller ◽

Robert D. Loberg ◽

Ming-Hui Fan ◽

Qihong Zhu ◽

James L. Park ◽

...

Keyword(s):

Glucose Uptake ◽

Glucose Transport ◽

Glucose Transporter ◽

Glycogen Synthase ◽

Cell Types ◽

Glycogen Synthase Kinase ◽

Glycogen Synthase Kinase 3 ◽

Glucose Transporter 1 ◽

Glut1 Expression ◽

Mutant Cells

Glucose transport is a highly regulated process and is dependent on a variety of signaling events. Glycogen synthase kinase-3 (GSK-3) has been implicated in various aspects of the regulation of glucose transport, but the mechanisms by which GSK-3 activity affects glucose uptake have not been well defined. We report that basal glycogen synthase kinase-3 (GSK-3) activity regulates glucose transport in several cell types. Chronic inhibition of basal GSK-3 activity (8–24 h) in several cell types, including vascular smooth muscle cells, resulted in an approximately twofold increase in glucose uptake due to a similar increase in protein expression of the facilitative glucose transporter 1 (GLUT1). Conversely, expression of a constitutively active form of GSK-3β resulted in at least a twofold decrease in GLUT1 expression and glucose uptake. Since GSK-3 can inhibit mammalian target of rapamycin (mTOR) signaling via phosphorylation of the tuberous sclerosis complex subunit 2 (TSC2) tumor suppressor, we investigated whether chronic GSK-3 effects on glucose uptake and GLUT1 expression depended on TSC2 phosphorylation and TSC inhibition of mTOR. We found that absence of functional TSC2 resulted in a 1.5-to 3-fold increase in glucose uptake and GLUT1 expression in multiple cell types. These increases in glucose uptake and GLUT1 levels were prevented by inhibition of mTOR with rapamycin. GSK-3 inhibition had no effect on glucose uptake or GLUT1 expression in TSC2 mutant cells, indicating that GSK-3 effects on GLUT1 and glucose uptake were mediated by a TSC2/mTOR-dependent pathway. The effect of GSK-3 inhibition on GLUT1 expression and glucose uptake was restored in TSC2 mutant cells by transfection of a wild-type TSC2 vector, but not by a TSC2 construct with mutated GSK-3 phosphorylation sites. Thus, TSC2 and rapamycin-sensitive mTOR function downstream of GSK-3 to modulate effects of GSK-3 on glucose uptake and GLUT1 expression. GSK-3 therefore suppresses glucose uptake via TSC2 and mTOR and may serve to match energy substrate utilization to cellular growth.

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Ultrastructural Study of a differentiating human colon carcinoma cell line

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100158583 ◽

1990 ◽

Vol 48 (3) ◽

pp. 208-209

Author(s):

Sylvie Polak-Charcon ◽

Mehrdad Hekmati ◽

Yehuda Ben Shaul

Keyword(s):

Cell Line ◽

Morphological Changes ◽

Secretory Granules ◽

Human Colon ◽

Cell Types ◽

Culture Conditions ◽

Morphological Evidence ◽

Human Colon Carcinoma Cell ◽

Colon Cell

The epithelium of normal human colon mucosa “in vivo” exhibits a gradual pattern of differentiation as undifferentiated stem cells from the base of the crypt of “lieberkuhn” rapidly divide, differentiate and migrate toward the free surface. The major differentiated cell type of the intestine observed are: absorptive cells displaying brush border, goblet cells containing mucous granules, Paneth and endocrine cells containing dense secretory granules. These different cell types are also found in the intestine of the 13-14 week old embryo.We present here morphological evidence showing that HT29, an adenocarcinoma of the human colon cell line, can differentiate into various cell types by changing the growth and culture conditions and mimic morphological changes found during development of the intestine in the human embryo.HT29 cells grown in tissue-culture dishes in DMEM and 10% FCS form at late confluence a multilayer of morphologically undifferentiated cell culture covered with irregular microvilli, and devoid of tight junctions (Figs 1-3).

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