δ-Opioid receptors stimulate GLUT1-mediated glucose uptake through Src- and IGF-1 receptor-dependent activation of PI3-kinase signalling in CHO cells.
OBJECTIVE
Although opioids have been reported to affect glucose homeostasis, relatively little is known on the role of δ-opioid receptors. We have investigated the regulation of glucose transport by human δ-opioid receptors expressed in Chinese hamster ovary cells.


METHODS
The uptake of [(3)H]-2-deoxy-D-glucose and 3-O-[methyl-[(3)H]]-D-glucose in response to δ-opioid receptor ligands and the expression of GLUT1, GLUT3 and GLUT4 glucose transporters were examined. Moreover, the effects of intracellular signal transduction inhibitors on δ-opioid receptor-regulated [(3)H]-2-deoxy-D-glucose uptake and protein phosphorylation were investigated.


RESULTS
Activation of δ-opioid receptors rapidly stimulated [(3)H]-2-deoxy-D-glucose and 3-O-[methyl-[(3)H]]-D-glucose uptakes, which were blocked by the GLUT inhibitors cytochalasin B and phloretin. The stimulation of [(3)H]-2-deoxy-D-glucose uptake that occurred without a change in plasma membrane GLUT1 - required the coupling to G(i) /G(o) proteins - was independent of cAMP and extracellular signal-regulated protein kinases, and was suppressed by blockade of Src and insulin-like growth factor-1 receptor (IGF-1R) tyrosine kinases. Inhibition of phosphatidylinositol 3-kinase (PI3K) by wortmannin or LY294002 and by PI3Kα, but not γ, isoform-selective inhibitors greatly reduced the δ-opioid receptor stimulation of glucose uptake. Moreover, the response was attenuated by overexpressing a dominant-negative kinase-deficient Akt form and by chemical inhibition of Akt. Stimulation of δ-opioid receptors increased protein kinase Cζ/λ (PKCζ/λ) phosphorylation and a selective PKCζ/λ inhibitor slightly reduced opioid stimulation of glucose uptake.


CONCLUSIONS
δ-Opioid receptors stimulated glucose transport probably by enhancing GLUT1 intrinsic activity through a signalling cascade involving G(i)/G(o), Src, IGF-1R, PI3Kα, Akt and, to a minor extent, PKCζ/λ. This effect may contribute to the opioid regulation of glucose homeostasis in physio-pathological conditions.
Section of Biochemical Pharmacology, Department of Neuroscience, University of Cagliari, Monserrato, Italy.
Maria C
MC
Olianas
Simona
S
Dedoni
Pierluigi
P
Onali
D000818:Animals; D001692:Biological Transport; D016466:CHO Cells; D002462:Cell Membrane / Q000378:metabolism; D006224:Cricetinae; D003412:Cricetulus; D000242:Cyclic AMP / Q000031:analogs & derivatives / Q000494:pharmacology; D003847:Deoxyglucose / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D051272:Glucose Transporter Type 1 / Q000037:antagonists & inhibitors / Q000502:physiology*; D006801:Humans; D007700:Kinetics; D008297:Male; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors; D037342:Pertussis Toxin / Q000494:pharmacology; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D051057:Proto-Oncogene Proteins c-akt / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D017526:Receptor, IGF Type 1 / Q000502:physiology*; D017465:Receptors, Opioid, delta / Q000819:agonists / Q000235:genetics / Q000502:physiology*; D014162:Transfection; D019061:src-Family Kinases / Q000037:antagonists & inhibitors / Q000502:physiology*
D051272:Glucose Transporter Type 1; D017465:Receptors, Opioid, delta; D003847:Deoxyglucose; D000242:Cyclic AMP; D037342:Pertussis Toxin; D019869:Phosphatidylinositol 3-Kinases; D017526:Receptor, IGF Type 1; D019061:src-Family Kinases; D051057:Proto-Oncogene Proteins c-akt; D011493:Protein Kinase C; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D005947:Glucose
Oncogene. 2000 Nov 20;19(49):5620-35
11114743
J Biol Chem. 1992 Apr 5;267(10):7021-5
1313029
Oncogene. 2001 Mar 26;20(13):1594-600
11313906
Nat Rev Drug Discov. 2005 Dec;4(12):988-1004
16341064
Am J Physiol Heart Circ Physiol. 2007 Sep;293(3):H1604-8
17545478
Metabolism. 2001 Dec;50(12):1402-8
11735084
Endocrinology. 1997 Apr;138(4):1427-33
9075698
Peptides. 1995;16(2):361-4
7784267
Nature. 2001 Dec 13;414(6865):799-806
11742412
Endocrinology. 2000 Nov;141(11):4146-55
11089547
Trends Endocrinol Metab. 2006 Mar;17(2):48-54
16460957
Nature. 1996 Apr 11;380(6574):541-4
8606776
J Biol Chem. 1990 Jul 25;265(21):12434-43
2165064
J Clin Invest. 1984 Oct;74(4):1473-80
6148357
Biochem J. 1998 Aug 1;333 ( Pt 3):471-90
9677303
J Biol Chem. 1989 Feb 25;264(6):3416-20
2644284
Horm Metab Res. 2004 Apr;36(4):210-4
15114518
J Cell Biol. 1992 May;117(4):729-43
1577853
Anal Biochem. 1976 May 7;72:248-54
942051
Mol Cell Biochem. 1999 Apr;194(1-2):109-16
10391130
Pflugers Arch. 2008 May;456(2):307-22
18071748
Endocrinology. 1997 Nov;138(11):4721-31
9348199
Anesth Analg. 1996 Jun;82(6):1237-41
8638797
Nat Med. 2005 Sep;11(9):936-43
16127437
Am J Physiol Cell Physiol. 2002 Jun;282(6):C1225-34
11997236
Biochem J. 1992 Nov 15;288 ( Pt 1):189-93
1445263
Pflugers Arch. 2001 Jul;442(4):614-21
11510895
Am J Physiol Heart Circ Physiol. 2005 Jun;288(6):H2744-9
15653765
Cell. 2006 May 19;125(4):733-47
16647110
Proc Natl Acad Sci U S A. 1994 Aug 2;91(16):7415-9
8052599
Am J Physiol Endocrinol Metab. 2004 Oct;287(4):E758-66
15172888
J Biol Chem. 1996 Dec 6;271(49):31562-71
8940173
Biochem J. 1992 Feb 1;281 ( Pt 3):829-34
1536658
Am J Physiol Endocrinol Metab. 2009 Oct;297(4):E836-48
19690067
J Biol Chem. 1996 Jan 12;271(2):695-701
8557675
Endocrinology. 2003 May;144(5):1753-60
12697680
Curr Biol. 1998 Sep 24;8(19):1069-77
9768361
Proc Natl Acad Sci U S A. 1991 Sep 1;88(17):7839-43
1881918
J Biol Chem. 2008 Oct 10;283(41):27653-27667
18669636
Biochem J. 1989 May 15;260(1):143-52
2775177
Int J Clin Pharmacol Ther Toxicol. 1990 Mar;28(3):89-98
2180828
Cell. 1995 Jun 2;81(5):727-36
7774014
Mol Cell Biol. 2003 Oct;23(20):7315-28
14517300
Diabetes. 2000 Dec;49(12):1978-85
11117997
Am J Physiol. 1999 Nov;277(5):F742-9
10564237
Diabetes. 2001 Dec;50(12):2815-21
11723065
Mol Endocrinol. 2009 May;23(5):671-8
19221053
Biochem Pharmacol. 1973 Dec 1;22(23):3099-108
4202581
Oncogene. 2004 Oct 18;23(48):7969-78
15489914
Science. 1995 Mar 24;267(5205):1782-8
7892601
J Biol Chem. 1993 Aug 15;268(23):17225-32
8349608
Pflugers Arch. 2004 Feb;447(5):480-9
12750891
Cell. 2000 Sep 1;102(5):635-46
11007482
Pharmacol Rev. 2004 Sep;56(3):351-69
15317908
Biochemistry (Mosc). 2006 Jul;71(7):701-6
16903823
Neuropsychopharmacology. 2007 Apr;32(4):773-85
16841075
Biochemistry. 2000 Dec 26;39(51):15705-12
11123895
Pharmacol Rev. 1999 Sep;51(3):503-32
10471416
Neurosci Lett. 2009 Nov 13;465(2):177-80
19682542