δ-Opioid Receptors Stimulate the Metabolic Sensor AMP-Activated Protein Kinase through Coincident Signaling with Gq/11-Coupled Receptors
- Section of Biochemical Pharmacology, Department of Neuroscience (M.C.O., S.D., P.O.) and Department of Sciences Applied to Biosystems (A.O.), University of Cagliari, Cagliari, Italy
- Address correspondence to:
Dr. Pierluigi Onali, Section of Biochemical Pharmacology, Department of Neuroscience, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato (Ca), Italy. E-mail: onali{at}unica.it
Abstract
AMP-activated protein kinase (AMPK) and δ-opioid receptors (DORs) are both involved in controlling cell survival, energy metabolism, and food intake, but little is known on the interaction between these two signaling molecules. Here we show that activation of human DORs stably expressed in Chinese hamster ovary (CHO) cells increased AMPK activity and AMPK phosphorylation on Thr172. DOR-induced AMPK phosphorylation was prevented by pertussis toxin, reduced by protein kinase A (PKA) activators, and unaffected by PKA, transforming growth factor-β-activated kinase 1, mitogen-activated protein kinase, and protein kinase C inhibitors. Conversely, the DOR effect was reduced by Ca2+/calmodulin-dependent protein kinase kinase (CaMKK) inhibition, apyrase treatment, Gq/11 antagonism, and blockade of P2 purinergic receptors. Apyrase treatment also depressed DOR stimulation of intracellular Ca2+ concentration, whereas P2 receptor antagonism blocked DOR stimulation of inositol phosphate accumulation. In SH-SY5Y neuroblastoma cells and primary olfactory bulb neurons, DOR activation failed to affect AMPK phosphorylation per se but potentiated the stimulation by either muscarinic agonists or 2-methyl-thio-ADP. Sequestration of G protein βγ subunits (Gβγ) blocked the DOR potentiation of AMPK phosphorylation induced by oxotremorine-M. In CHO cells, the AMPK activator 5-aminoimidazole-4-carboxamide1-β-d-ribonucleoside stimulated AMPK phosphorylation and glucose uptake, whereas pharmacological inhibition of AMPK, expression of a dominant-negative mutant of AMPKα1, and P2Y receptor blockade reduced DOR-stimulated glucose uptake. The data indicate that in different cell systems, DOR activation up-regulates AMPK through a Gβγ-dependent synergistic interaction with Gq/11-coupled receptors, potentiating Ca2+ release and CaMKKβ-dependent AMPK phosphorylation. In CHO cells, this coincident signaling mechanism is involved in DOR-induced glucose uptake.
Footnotes
-
Article, publication date, and citation information can be found at http://molpharm.aspetjournals.org.
-
ABBREVIATIONS:
- ACC
- acetyl-coenzyme A carboxylase
- ADV
- adenovirus
- AICAR
- 5-aminoimidazole-4-carboxamide1-β-d-ribonucleoside
- AMPK
- AMP-activated protein kinase
- ANOVA
- analysis of variance
- BSA
- bovine serum albumin
- CaMKK
- Ca2+/calmodulin-dependent protein kinase kinase
- CCh
- carbachol
- CHO
- Chinese hamster ovary
- CHO/DOR
- CHO cells stably expressing human DOR
- compound C
- 6-[4-[2-(1-piperidinyl)ethoxy]phenyl]-3-(4-pyridinyl)-pyrazolo[1,5-a]pyrimidine
- dBcAMP
- dibutyryl-cAMP
- DN
- dominant-negative
- DOR
- δ-opioid receptors
- DPDPE
- [d-Pen(2,5)]-enkephalin
- DTT
- dithiothreitol
- FCS
- fetal calf serum
- GLUT
- glucose transporter
- Go 6983
- 3-[1-[3-(dimethylamino)propyl]-5-methoxy-1H-indol-3-yl]-4-(1H-indol-3-yl)-1H-pyrrole-2,5-dione
- GRK2-CT
- C-terminal region of G protein-coupled receptor kinase 2
- HPLC
- high-performance liquid chromatography
- IGF-1
- insulin-like growth factor-1
- IP
- inositol phosphate
- LDH
- lactate dehydrogenase
- MAP
- mitogen-activated protein
- MeSADP
- 2-methylthio ADP
- MRS 2179
- N6-methyl 2′-deoxyadenosine 3′,5′-bisphosphate
- naltrindole
- 17-(cyclopropylmethyl)-6,7-dehydro-4,5α-epoxy-3,14-dihydroxy-6,7–2′,3′-indolomorphinan
- NTI
- naltrindole
- Oxo-M
- oxotremorine-M
- PBS
- phosphate-buffered saline
- PD 98059
- 2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one
- PI3K
- phosphatidylinositol 3-kinase
- PKA
- protein kinase A
- PKC
- protein kinase C
- PLC
- phospholipase C
- PPADS
- pyridoxalphosphate-6-azophenyl-2′,4′-disulfonic acid
- PTX
- Bordetella pertussis toxin
- Rp-cAMPS
- adenosine-3′,5′-cyclic monophosphorothioate, Rp-isomer
- SB203580
- 4-[5-(4-fluorophenyl)-2-[4-(methylsulphonyl)phenyl]-1H-imidazol-4-yl]pyridine
- SAMS peptide
- HMRSAMSGLHLVKRR
- SNC 80
- (+)-4-[(αR)-α-((2S,5R)-4-Allyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide
- SP600125
- anthra[1–9-cd]pyrazol-6(2H)-one
- Sp-cAMPS
- adenosine-3′,5′-cyclic monophosphorothioate, Sp-isomer
- STO-609
- 7-oxo-7H-benzimidazo[2,1-a]benz[de]isoquinoline-3-carboxylic acid
- TAK1
- transforming growth factor-β-activated kinase 1.
- Received August 11, 2011.
- Accepted October 26, 2011.
- Copyright © 2012 The American Society for Pharmacology and Experimental Therapeutics
