51
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Lückmann M, Holst B, Schwartz TW, Frimurer TM. In Silico Investigation of the Neurotensin Receptor 1 Binding Site: Overlapping Binding Modes for Small Molecule Antagonists and the Endogenous Peptide Agonist. Mol Inform 2015; 35:19-24. [PMID: 27491650 DOI: 10.1002/minf.201500080] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 08/14/2015] [Indexed: 12/17/2022]
Abstract
The neurotensin receptor 1 (NTSR1) belongs to the family of 7TM, G protein-coupled receptors, and is activated by the 13-amino-acid peptide neurotensin (NTS) that has been shown to play important roles in neurological disorders and the promotion of cancer cells. Recently, a high-resolution x-ray crystal structure of NTSR1 in complex with NTS8-13 has been determined, providing novel insights into peptide ligand recognition by 7TM receptors. SR48692, a potent and selective small molecule antagonist has previously been used extensively as a tool compound to study NTSR1 receptor signaling properties. To investigate the binding mode of SR48692 and other small molecule compounds to NTSR1, we applied an Automated Ligand-guided Backbone Ensemble Receptor Optimization protocol (ALiBERO), taking receptor flexibility and ligand knowledge into account. Structurally overlapping binding poses for SR48692 and NTS8-13 were observed, despite their distinct chemical nature and inverse pharmacological profiles. The optimized models showed significantly improved ligand recognition in a large-scale virtual screening assessment compared to the crystal structure. Our models provide new insights into small molecule ligand binding to NTSR1 and could facilitate the structure-based design of non-peptide ligands for the evaluation of the pharmacological potential of NTSR1 in neurological disorders and cancer.
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Affiliation(s)
- Michael Lückmann
- M Lückmann, B Holst, TW Schwartz, TM Frimurer, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen. Denmark
| | - Birgitte Holst
- M Lückmann, B Holst, TW Schwartz, TM Frimurer, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen. Denmark
| | - Thue W Schwartz
- M Lückmann, B Holst, TW Schwartz, TM Frimurer, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen. Denmark
| | - Thomas M Frimurer
- M Lückmann, B Holst, TW Schwartz, TM Frimurer, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen. Denmark. .,TM Frimurer, Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen. Denmark.
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52
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Osadchii OE. Emerging role of neurotensin in regulation of the cardiovascular system. Eur J Pharmacol 2015; 762:184-92. [DOI: 10.1016/j.ejphar.2015.05.025] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 04/29/2015] [Accepted: 05/11/2015] [Indexed: 10/23/2022]
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Abstract
We previously determined the structure of neurotensin receptor NTSR1 in an active-like conformation with six thermostabilizing mutations bound to the peptide agonist neurotensin. This receptor was unable to activate G proteins, indicating that the mutations restricted NTSR1 to relate agonist binding to G-protein activation. Here we analyse the effect of three of those mutations (E166A3.49, L310A6.37, F358A7.42) and present two structures of NTSR1 able to catalyse nucleotide exchange at Gα. The presence of F3587.42 causes the conserved W3216.48 to adopt a side chain orientation parallel to the lipid bilayer sealing the collapsed Na+ ion pocket and linking the agonist with residues in the lower receptor part implicated in GPCR activation. In the intracellular receptor half, the bulkier L3106.37 side chain dictates the position of R1673.50 of the highly conserved D/ERY motif. These residues, together with the presence of E1663.49 provide determinants for G-protein activation by NTSR1. The structural basis of how G-protein coupled receptors respond to unique stimuli remains poorly understood. Here, Krumm et al. present new structures of the neurotensin receptor and reveal insights into how ligand binding is linked to structural rearrangements associated with receptor activation.
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54
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Inagaki S, Ghirlando R, Vishnivetskiy SA, Homan KT, White JF, Tesmer JJG, Gurevich VV, Grisshammer R. G Protein-Coupled Receptor Kinase 2 (GRK2) and 5 (GRK5) Exhibit Selective Phosphorylation of the Neurotensin Receptor in Vitro. Biochemistry 2015; 54:4320-9. [PMID: 26120872 PMCID: PMC4512254 DOI: 10.1021/acs.biochem.5b00285] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
![]()
G protein-coupled
receptor kinases (GRKs) play an important role
in the desensitization of G protein-mediated signaling of G protein-coupled
receptors (GPCRs). The level of interest in mapping their phosphorylation
sites has increased because recent studies suggest that the differential
pattern of receptor phosphorylation has distinct biological consequences. In vitro phosphorylation experiments using well-controlled
systems are useful for deciphering the complexity of these physiological
reactions and understanding the targeted event. Here, we report on
the phosphorylation of the class A GPCR neurotensin receptor 1 (NTSR1)
by GRKs under defined experimental conditions afforded by nanodisc
technology. Phosphorylation of NTSR1 by GRK2 was agonist-dependent,
whereas phosphorylation by GRK5 occurred in an activation-independent
manner. In addition, the negatively charged lipids in the immediate
vicinity of NTSR1 directly affect phosphorylation by GRKs. Identification
of phosphorylation sites in agonist-activated NTSR1 revealed that
GRK2 and GRK5 target different residues located on the intracellular
receptor elements. GRK2 phosphorylates only the C-terminal Ser residues,
whereas GRK5 phosphorylates Ser and Thr residues located in intracellular
loop 3 and the C-terminus. Interestingly, phosphorylation assays using
a series of NTSR1 mutants show that GRK2 does not require acidic residues
upstream of the phospho-acceptors for site-specific phosphorylation,
in contrast to the β2-adrenergic and μ-opioid
receptors. Differential phosphorylation of GPCRs by GRKs is thought
to encode a particular signaling outcome, and our in vitro study revealed NTSR1 differential phosphorylation by GRK2 and GRK5.
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Affiliation(s)
- Sayaka Inagaki
- †Membrane Protein Structure Function Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Department of Health and Human Services, Rockville, Maryland 20852, United States
| | - Rodolfo Ghirlando
- ‡Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland 20892, United States
| | - Sergey A Vishnivetskiy
- §Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Kristoff T Homan
- ∥Departments of Pharmacology and Biological Sciences, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Jim F White
- †Membrane Protein Structure Function Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Department of Health and Human Services, Rockville, Maryland 20852, United States
| | - John J G Tesmer
- ∥Departments of Pharmacology and Biological Sciences, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Vsevolod V Gurevich
- §Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Reinhard Grisshammer
- †Membrane Protein Structure Function Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Department of Health and Human Services, Rockville, Maryland 20852, United States
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55
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Law IKM, Bakirtzi K, Polytarchou C, Oikonomopoulos A, Hommes D, Iliopoulos D, Pothoulakis C. Neurotensin--regulated miR-133α is involved in proinflammatory signalling in human colonic epithelial cells and in experimental colitis. Gut 2015; 64:1095-104. [PMID: 25112884 PMCID: PMC4422787 DOI: 10.1136/gutjnl-2014-307329] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 07/22/2014] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Neurotensin (NT) mediates colonic inflammation through its receptor neurotensin receptor 1 (NTR1). NT stimulates miR-133α expression in colonic epithelial cells. We investigated the role of miR-133α in NT-associated colonic inflammation in vitro and in vivo. DESIGN miR-133α and aftiphilin (AFTPH) levels were measured by quantitative PCR. Antisense (as)-miR-133α was administrated intracolonicaly prior to induction of 2, 4, 6-trinitrobenzene sulfonic acid (TNBS)-induced colitis and dextran sodium sulfate (DSS)-induced colitis. The effect of AFTPH was examined by gene silencing in vitro. RESULTS NT increased miR-133α levels in NCM-460 overexpressing NTR1 (NCM460-NTR1) and HCT-116 cells. NT-induced p38, ERK1/2, c-Jun, and NF-κB activation, as well as IL-6, IL-8 and IL-1β messenger RNA (mRNA) expression in NCM-460-NTR1 cells were reduced in miR-133α-silenced cells, while overexpression of miR-133α reversed these effects. MiR-133α levels were increased in TNBS (2 day) and DSS (5 day) colitis, while NTR1 deficient DSS-exposed mice had reduced miR-133α levels, compared to wild-type colitic mice. Intracolonic as-miR-133α attenuated several parameters of colitis as well expression of proinflammatory mediators in the colonic mucosa. In silico search coupled with qPCR identified AFTPH as a downstream target of miR-133α, while NT decreased AFTPH expression in NCM-460-NTR1 colonocytes. Gene silencing of AFTPH enhanced NT-induced proinflammatory responses and AFTPH levels were downregulated in experimental colitis. Levels of miR-133α were significantly upregulated, while AFTPH levels were downregulated in colonic biopsies of patients with ulcerative colitis compared to controls. CONCLUSIONS NT-associated colitis and inflammatory signalling are regulated by miR-133α-AFTPH interactions. Targeting of miR-133α or AFTPH may represent a novel therapeutic approach in inflammatory bowel disease.
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Affiliation(s)
- Ivy Ka Man Law
- Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, UCLA, Los Angeles, California, USA
| | - Kyriaki Bakirtzi
- Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, UCLA, Los Angeles, California, USA
| | - Christos Polytarchou
- Center for Systems Biomedicine, Division of Digestive Diseases, David Geffen School of Medicine, UCLA, Los Angeles, California, USA
| | - Angelos Oikonomopoulos
- Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, UCLA, Los Angeles, California, USA
| | - Daniel Hommes
- Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, UCLA, Los Angeles, California, USA
| | - Dimitrios Iliopoulos
- Center for Systems Biomedicine, Division of Digestive Diseases, David Geffen School of Medicine, UCLA, Los Angeles, California, USA
| | - Charalabos Pothoulakis
- Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, UCLA, Los Angeles, California, USA
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56
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Xiao S, Chen YC, Betenbaugh MJ, Martin SE, Shiloach J. MiRNA mimic screen for improved expression of functional neurotensin receptor from HEK293 cells. Biotechnol Bioeng 2015; 112:1632-43. [PMID: 25676429 DOI: 10.1002/bit.25567] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 01/23/2015] [Accepted: 02/05/2015] [Indexed: 01/17/2023]
Abstract
Obtaining adequate quantities of functional mammalian membrane proteins has been a bottleneck in their structural and functional studies because the expression of these proteins from mammalian cells is relatively low. To explore the possibility of enhancing expression of these proteins using miRNA, a stable T-REx-293 cell line expressing the neurotensin receptor type 1 (NTSR1), a hard-to-express G protein-coupled receptor (GPCR), was constructed. The cell line was then subjected to human miRNA mimic library screening. In parallel, an HEK293 cell line expressing luciferase was also screened with the same human miRNA mimic library. Five microRNA mimics: hsa-miR-22-5p, hsa-miR-18a-5p, hsa-miR-22-3p, hsa-miR-429, and hsa-miR-2110were identified from both screens. They led to 48% increase in the expression of functional NTSR1 and to 239% increase of luciferase expression. These miRNAs were also effective in enhancing the expression of secretedglypican-3 hFc-fusion protein from HEK293 cells.The results indicate that these molecules may have a wide role in enhancing the production of proteins with biomedical interest.
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Affiliation(s)
- Su Xiao
- Biotechnology Core Laboratory, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, 20892.,Departments of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Yu-Chi Chen
- NIH Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of health, Rockville, Maryland, 20850
| | - Michael J Betenbaugh
- Departments of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Scott E Martin
- NIH Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of health, Rockville, Maryland, 20850.
| | - Joseph Shiloach
- Biotechnology Core Laboratory, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, 20892.
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57
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Egloff P, Deluigi M, Heine P, Balada S, Plückthun A. A cleavable ligand column for the rapid isolation of large quantities of homogeneous and functional neurotensin receptor 1 variants from E. coli. Protein Expr Purif 2015; 108:106-114. [DOI: 10.1016/j.pep.2014.10.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 10/03/2014] [Accepted: 10/10/2014] [Indexed: 12/29/2022]
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58
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Dash A, Chakraborty S, Pillai MRA, Knapp FFR. Peptide receptor radionuclide therapy: an overview. Cancer Biother Radiopharm 2015; 30:47-71. [PMID: 25710506 DOI: 10.1089/cbr.2014.1741] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Peptide receptor radionuclide therapy (PRRT) is a site-directed targeted therapeutic strategy that specifically uses radiolabeled peptides as biological targeting vectors designed to deliver cytotoxic levels of radiation dose to cancer cells, which overexpress specific receptors. Interest in PRRT has steadily grown because of the advantages of targeting cellular receptors in vivo with high sensitivity as well as specificity and treatment at the molecular level. Recent advances in molecular biology have not only stimulated advances in PRRT in a sustainable manner but have also pushed the field significantly forward to several unexplored possibilities. Recent decades have witnessed unprecedented endeavors for developing radiolabeled receptor-binding somatostatin analogs for the treatment of neuroendocrine tumors, which have played an important role in the evolution of PRRT and paved the way for the development of other receptor-targeting peptides. Several peptides targeting a variety of receptors have been identified, demonstrating their potential to catalyze breakthroughs in PRRT. In this review, the authors discuss several of these peptides and their analogs with regard to their applications and potential in radionuclide therapy. The advancement in the availability of combinatorial peptide libraries for peptide designing and screening provides the capability of regulating immunogenicity and chemical manipulability. Moreover, the availability of a wide range of bifunctional chelating agents opens up the scope of convenient radiolabeling. For these reasons, it would be possible to envision a future where the scope of PRRT can be tailored for patient-specific application. While PRRT lies at the interface between many disciplines, this technology is inextricably linked to the availability of the therapeutic radionuclides of required quality and activity levels and hence their production is also reviewed.
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Affiliation(s)
- Ashutosh Dash
- 1 Isotope Production and Applications Division, Bhabha Atomic Research Centre , Mumbai, India
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59
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Brown JA, Woodworth HL, Leinninger GM. To ingest or rest? Specialized roles of lateral hypothalamic area neurons in coordinating energy balance. Front Syst Neurosci 2015; 9:9. [PMID: 25741247 PMCID: PMC4332303 DOI: 10.3389/fnsys.2015.00009] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 01/15/2015] [Indexed: 12/26/2022] Open
Abstract
Survival depends on an organism’s ability to sense nutrient status and accordingly regulate intake and energy expenditure behaviors. Uncoupling of energy sensing and behavior, however, underlies energy balance disorders such as anorexia or obesity. The hypothalamus regulates energy balance, and in particular the lateral hypothalamic area (LHA) is poised to coordinate peripheral cues of energy status and behaviors that impact weight, such as drinking, locomotor behavior, arousal/sleep and autonomic output. There are several populations of LHA neurons that are defined by their neuropeptide content and contribute to energy balance. LHA neurons that express the neuropeptides melanin-concentrating hormone (MCH) or orexins/hypocretins (OX) are best characterized and these neurons play important roles in regulating ingestion, arousal, locomotor behavior and autonomic function via distinct neuronal circuits. Recently, another population of LHA neurons containing the neuropeptide Neurotensin (Nts) has been implicated in coordinating anorectic stimuli and behavior to regulate hydration and energy balance. Understanding the specific roles of MCH, OX and Nts neurons in harmonizing energy sensing and behavior thus has the potential to inform pharmacological strategies to modify behaviors and treat energy balance disorders.
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Affiliation(s)
- Juliette A Brown
- Department of Pharmacology and Toxicology, Michigan State University East Lansing, MI, USA ; Center for Integrative Toxicology East Lansing, MI, USA
| | | | - Gina M Leinninger
- Center for Integrative Toxicology East Lansing, MI, USA ; Department of Physiology, Michigan State University East Lansing, MI, USA
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60
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Repeated effects of the neurotensin receptor agonist PD149163 in three animal tests of antipsychotic activity: assessing for tolerance and cross-tolerance to clozapine. Pharmacol Biochem Behav 2014; 128:78-88. [PMID: 25433325 DOI: 10.1016/j.pbb.2014.11.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 11/04/2014] [Accepted: 11/07/2014] [Indexed: 01/07/2023]
Abstract
Neurotensin is an endogenous neuropeptide closely associated with the mesolimbic dopaminergic system and shown to possess antipsychotic-like effects. In particular, acute neurotensin receptor activation can inhibit conditioned avoidance response (CAR), attenuate phencyclidine (PCP)-induced prepulse inhibition (PPI) disruptions, and reverse PCP-induced hyperlocomotion. However, few studies have examined the long term effects of repeated neurotensin receptor activation and results are inconsistent. Since clinical administration of antipsychotic therapy often requires a prolonged treatment schedule, here we assessed the effects of repeated activation of neurotensin receptors using an NTS1 receptor selective agonist, PD149163, in 3 behavioral tests of antipsychotic activity. We also investigated whether reactivity to the atypical antipsychotic clozapine was altered following prior PD149163 treatment. Using both normal and prenatally immune activated rats generated through maternal immune activation with polyinosinic:polycytidylic acid, we tested PD149163 in CAR, PCP (1.5mg/kg)-induced PPI disruption, and PCP (3.2mg/kg)-induced hyperlocomotion. For each paradigm, rats were first repeatedly tested with vehicle or PD149163 (1.0, 4.0, 8.0mg/kg, sc) along with vehicle or PCP for PPI and hyperlocomotion tests, then challenged with PD149163 after 2 drug-free days. All rats were then challenged with clozapine (5.0mg/kg, sc). During the repeated test period, PD149163 exhibited antipsychotic-like effects in all three models. On the PD149163 challenge day, prior drug treatment only caused a tolerance effect in CAR. This tolerance in CAR was transferrable to clozapine, as it enhanced clozapine tolerance in the same group of animals. Although no tolerance effect was seen in the PD149163 challenge for the PCP-induced hyperlocomotion test, the clozapine challenge showed increased sensitivity in groups previously exposed to repeated PD149163 treatment. Our findings suggest that repeated exposure to NTS1 receptor agonists can induce a dose-dependent tolerance and cross-tolerance to clozapine to some of its behavioral effects but not others.
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61
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Schaab C, Kling RC, Einsiedel J, Hübner H, Clark T, Seebach D, Gmeiner P. Structure-based evolution of subtype-selective neurotensin receptor ligands. ChemistryOpen 2014; 3:206-18. [PMID: 25478316 PMCID: PMC4234217 DOI: 10.1002/open.201402031] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Indexed: 11/08/2022] Open
Abstract
Subtype-selective agonists of the neurotensin receptor NTS2 represent a promising option for the treatment of neuropathic pain, as NTS2 is involved in the mediation of μ-opioid-independent anti-nociceptive effects. Based on the crystal structure of the subtype NTS1 and previous structure-activity relationships (SARs) indicating a potential role for the sub-pocket around Tyr11 of NT(8-13) in subtype-specific ligand recognition, we have developed new NTS2-selective ligands. Starting from NT(8-13), we replaced the tyrosine unit by β(2)-amino acids (type 1), by heterocyclic tyrosine bioisosteres (type 2) and peptoid analogues (type 3). We were able to evolve an asymmetric synthesis of a 5-substituted azaindolylalanine and its application as a bioisostere of tyrosine capable of enhancing NTS2 selectivity. The S-configured test compound 2 a, [(S)-3-(pyrazolo[1,5-a]pyridine-5-yl)-propionyl(11)]NT(8-13), exhibits substantial NTS2 affinity (4.8 nm) and has a nearly 30-fold NTS2 selectivity over NTS1. The (R)-epimer 2 b showed lower NTS2 affinity but more than 600-fold selectivity over NTS1.
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Affiliation(s)
- Carolin Schaab
- Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich Alexander University Schuhstraße 19, 91052 Erlangen (Germany) E-mail:
| | - Ralf Christian Kling
- Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich Alexander University Schuhstraße 19, 91052 Erlangen (Germany) E-mail: ; Department of Chemistry and Pharmacy, Computer Chemistry Center, Friedrich Alexander University Nägelsbachstraße 25, 91052 Erlangen (Germany)
| | - Jürgen Einsiedel
- Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich Alexander University Schuhstraße 19, 91052 Erlangen (Germany) E-mail:
| | - Harald Hübner
- Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich Alexander University Schuhstraße 19, 91052 Erlangen (Germany) E-mail:
| | - Tim Clark
- Department of Chemistry and Pharmacy, Computer Chemistry Center, Friedrich Alexander University Nägelsbachstraße 25, 91052 Erlangen (Germany)
| | - Dieter Seebach
- Departement of Chemistry and Applied Bioscience, Laboratory of Organic Chemistry ETH Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich (Switzerland)
| | - Peter Gmeiner
- Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich Alexander University Schuhstraße 19, 91052 Erlangen (Germany) E-mail:
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62
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Masuda K, Iwakoshi-Ukena E, Bessho Y, Taniuchi S, Maejima S, Shikano K, Kondo K, Furumitsu M, Ukena K. Identification of neurotensin and LANT-6 and localization of mRNA encoding their precursor in the chicken brain. Zoolog Sci 2014; 31:353-9. [PMID: 24882095 DOI: 10.2108/zs140010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Neurotensin (NT) and neurotensin-related peptide (Lys(8), Asn(9), NT(8-13): LANT-6) have previously been purified from chicken intestine. However, the presence of these peptides and the localization of their precursor mRNA in the brain were not well understood. In the present study, through a comprehensive analysis of bioactive substances, NT and LANT-6 were identified in the chicken brain using tandem mass spectrometry combined with a bioassay of the colon contraction. The effect of NT and LANT-6 on the colon contraction was assessed, and NT was found to be 10 times more potent than LANT-6. Furthermore, the sites of NT/LANT-6 precursor mRNA expression in the brain were investigated using quantitative RT-PCR. The result showed that the mRNA was expressed most in the telencephalon, followed by the diencephalon. In situ hybridization analysis revealed that cells containing NT/LANT-6 precursor mRNA were widely distributed throughout the brain except for the cerebellum. Additionally, these were highly concentrated in the frontal telencephalon, including the nidopallium, hyperpallium, and hippocampus. Collectively, these results indicate that NT and LANT-6 are produced in the chicken brain, and they may participate in multiple functions.
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Affiliation(s)
- Keiko Masuda
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
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63
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Thomas JB, Giddings AM, Wiethe RW, Olepu S, Warner KR, Sarret P, Gendron L, Longpre JM, Zhang Y, Runyon SP, Gilmour BP. Identification of N-[(5-{[(4-methylphenyl)sulfonyl]amino}-3-(trifluoroacetyl)-1H-indol-1-yl)acetyl]-l-leucine (NTRC-824), a neurotensin-like nonpeptide compound selective for the neurotensin receptor type 2. J Med Chem 2014; 57:7472-7. [PMID: 25157640 PMCID: PMC4161155 DOI: 10.1021/jm500857r] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
![]()
Compounds acting via the neurotensin
receptor type 2 (NTS2) are
known to be active in animal models of acute and chronic pain. To
identify novel NTS2 selective analgesics, we searched for NTS2 selective
nonpeptide compounds using a FLIPR assay and identified the title
compound (NTRC-824, 5) that, to our knowledge, is the
first nonpeptide that is selective for NTS2 versus NTS1 and behaves
like the endogenous ligand neurotensin in the functional assay.
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Affiliation(s)
- James B Thomas
- Center for Organic and Medicinal Chemistry, Research Triangle Institute , P.O. Box 12194, 3040 Cornwallis Road, Research Triangle Park, North Carolina 27709, United States
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64
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Elucidating the role of neurotensin in the pathophysiology and management of major mental disorders. Behav Sci (Basel) 2014; 4:125-153. [PMID: 25379273 PMCID: PMC4219245 DOI: 10.3390/bs4020125] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 05/15/2014] [Accepted: 05/21/2014] [Indexed: 12/30/2022] Open
Abstract
Neurotensin (NT) is a neuropeptide that is closely associated with, and is thought to modulate, dopaminergic and other neurotransmitter systems involved in the pathophysiology of various mental disorders. This review outlines data implicating NT in the pathophysiology and management of major mental disorders such as schizophrenia, drug addiction, and autism. The data suggest that NT receptor analogs have the potential to be used as novel therapeutic agents acting through modulation of neurotransmitter systems dys-regulated in these disorders.
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65
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Activation of neurotensin receptor type 1 attenuates locomotor activity. Neuropharmacology 2014; 85:482-92. [PMID: 24929110 DOI: 10.1016/j.neuropharm.2014.05.046] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 05/28/2014] [Accepted: 05/30/2014] [Indexed: 12/16/2022]
Abstract
Intracerebroventricular administration of neurotensin (NT) suppresses locomotor activity. However, the brain regions that mediate the locomotor depressant effect of NT and receptor subtype-specific mechanisms involved are unclear. Using a brain-penetrating, selective NT receptor type 1 (NTS1) agonist PD149163, we investigated the effect of systemic and brain region-specific NTS1 activation on locomotor activity. Systemic administration of PD149163 attenuated the locomotor activity of C57BL/6J mice both in a novel environment and in their homecage. However, mice developed tolerance to the hypolocomotor effect of PD149163 (0.1 mg/kg, i.p.). Since NTS1 is known to modulate dopaminergic signaling, we examined whether PD149163 blocks dopamine receptor-mediated hyperactivity. Pretreatment with PD149163 (0.1 or 0.05 mg/kg, i.p.) inhibited D2R agonist bromocriptine (8 mg/kg, i.p.)-mediated hyperactivity. D1R agonist SKF-81297 (8 mg/kg, i.p.)-induced hyperlocomotion was only inhibited by 0.1 mg/kg of PD149163. Since the nucleus accumbens (NAc) and medial prefrontal cortex (mPFC) have been implicated in the behavioral effects of NT, we examined whether microinjection of PD149163 into these regions reduces locomotion. Microinjection of PD149163 (2 pmol) into the NAc, but not the mPFC suppressed locomotor activity. In summary, our results indicate that systemic and intra-NAc activation of NTS1 is sufficient to reduce locomotion and NTS1 activation inhibits D2R-mediated hyperactivity. Our study will be helpful to identify pharmacological factors and a possible therapeutic window for NTS1-targeted therapies for movement disorders.
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66
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Thomas JB, Giddings AM, Wiethe RW, Olepu S, Warner KR, Sarret P, Gendron L, Longpre JM, Zhang Y, Runyon SP, Gilmour BP. Identification of 1-({[1-(4-fluorophenyl)-5-(2-methoxyphenyl)-1H-pyrazol-3-yl]carbonyl}amino)cyclohexane carboxylic acid as a selective nonpeptide neurotensin receptor type 2 compound. J Med Chem 2014; 57:5318-32. [PMID: 24856674 PMCID: PMC4216214 DOI: 10.1021/jm5003843] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
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Compounds
active at neurotensin receptors (NTS1 and NTS2) exert analgesic effects
on different types of nociceptive modalities, including thermal, mechanical,
and chemical stimuli. The NTS2 preferring peptide JMV-431 (2) and the NTS2 selective nonpeptide compound levocabastine (6) have been shown to be effective in relieving the pain associated
with peripheral neuropathies. With the aim of identifying novel nonpeptide
compounds selective for NTS2, we examined analogues of SR48692 (5a) using a FLIPR calcium assay in CHO cells stably expressing
rat NTS2. This led to the discovery of the NTS2 selective nonpeptide
compound 1-({[1-(4-fluorophenyl)-5-(2-methoxyphenyl)-1H-pyrazol-3-yl]carbonyl}amino)cyclohexane carboxylic acid (NTRC-739, 7b) starting from the nonselective compound 5a.
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Affiliation(s)
- James B Thomas
- Center for Organic and Medicinal Chemistry, Research Triangle Institute , P.O. Box 12194, Research Triangle Park, North Carolina 27709, United States
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67
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Yasuda SI, Ishida J. GPR39-1b, the 5-transmembrane isoform of GPR39 interacts with neurotensin receptor NTSR1 and modifies its function. J Recept Signal Transduct Res 2014; 34:307-12. [PMID: 24512471 DOI: 10.3109/10799893.2014.885050] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
G-protein-coupled receptor 39 (GPR39), a member of the ghrelin receptor family, has a full-length isoform GPR39-1a and a truncated isoform GPR39-1b. While GPR39-1a was clarified as a receptor of Zn(2+), the characteristic property of GPR39-1b remains unknown. Therefore, in this study, the molecular functions of GPR39-1b were explored in cell culture. In contrast to GPR39-1a, GPR39-1b showed no response to Zn(2+) stimulation in calcium mobilization assays, suggesting that GPR39-1b is not a functional receptor of Zn(2+). To understand the signaling interaction of GPR39-1b, we investigated the dimerization between the isoforms, and conducted bioluminescence resonance energy transfer (BRET(2)) assays. The results indicated that GPR39-1b homodimerized, but did not heterodimerize with GPR39-1a. We subsequently attempted to search the heterodimeric counterparts of GPR39-1b. Neurotensin receptor 1 (NTSR1) was also targeted as a GPR39-1b interacting partner because of its highly conserved amino acid sequence and mRNA localization, which was similar to GPR39-1b. BRET(2) assays demonstrated that GPR39-1b heterodimerized with NTSR1. To examine the effect of GPR39-1b on NTRS1-mediated cAMP/PKA signaling, we used the cAMP responsive element-luciferase assays and observed that GPR39-1b attenuated neurotensin-induced NTSR1 signaling. Taken together, our results provided a novel regulatory mechanism for GPR39-1b in NTRS1 signaling.
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Affiliation(s)
- Shin-ichiro Yasuda
- Pharmacology Research Laboratories II, Mitsubishi Tanabe Pharma Corporation , Kawagishi, Toda-shi, Saitama , Japan and
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68
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Structure of signaling-competent neurotensin receptor 1 obtained by directed evolution in Escherichia coli. Proc Natl Acad Sci U S A 2014; 111:E655-62. [PMID: 24453215 DOI: 10.1073/pnas.1317903111] [Citation(s) in RCA: 168] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Crystallography has advanced our understanding of G protein-coupled receptors, but low expression levels and instability in solution have limited structural insights to very few selected members of this large protein family. Using neurotensin receptor 1 (NTR1) as a proof of principle, we show that two directed evolution technologies that we recently developed have the potential to overcome these problems. We purified three neurotensin-bound NTR1 variants from Escherichia coli and determined their X-ray structures at up to 2.75 Å resolution using vapor diffusion crystallization experiments. A crystallized construct was pharmacologically characterized and exhibited ligand-dependent signaling, internalization, and wild-type-like agonist and antagonist affinities. Our structures are fully consistent with all biochemically defined ligand-contacting residues, and they represent an inactive NTR1 state at the cytosolic side. They exhibit significant differences to a previously determined NTR1 structure (Protein Data Bank ID code 4GRV) in the ligand-binding pocket and by the presence of the amphipathic helix 8. A comparison of helix 8 stability determinants between NTR1 and other crystallized G protein-coupled receptors suggests that the occupancy of the canonical position of the amphipathic helix is reduced to various extents in many receptors, and we have elucidated the sequence determinants for a stable helix 8. Our analysis also provides a structural rationale for the long-known effects of C-terminal palmitoylation reactions on G protein-coupled receptor signaling, receptor maturation, and desensitization.
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69
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Driessen TM, Zhao C, Whittlinger A, Williams H, Gammie SC. Endogenous CNS expression of neurotensin and neurotensin receptors is altered during the postpartum period in outbred mice. PLoS One 2014; 9:e83098. [PMID: 24416154 PMCID: PMC3885409 DOI: 10.1371/journal.pone.0083098] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Accepted: 11/05/2013] [Indexed: 12/26/2022] Open
Abstract
Neurotensin (NT) is a neuropeptide identical in mice and humans that is produced and released in many CNS regions associated with maternal behavior. NT has been linked to aspects of maternal care and previous studies have indirectly suggested that endogenous NT signaling is altered in the postpartum period. In the present study, we directly examine whether NT and its receptors exhibit altered gene expression in maternal relative to virgin outbred mice using real time quantitative PCR (qPCR) across multiple brain regions. We also examine NT protein levels using anti-NT antibodies and immunohistochemistry in specific brain regions. In the medial preoptic area (MPOA), which is critical for maternal behaviors, mRNA of NT and NT receptor 3 (Sort1) were significantly up-regulated in postpartum mice compared to virgins. NT mRNA was also elevated in postpartum females in the bed nucleus of the stria terminalis dorsal. However, in the lateral septum, NT mRNA was down-regulated in postpartum females. In the paraventricular nucleus of the hypothalamus (PVN), Ntsr1 expression was down-regulated in postpartum females. Neurotensin receptor 2 (Ntsr2) expression was not altered in any brain region tested. In terms of protein expression, NT immunohistochemistry results indicated that NT labeling was elevated in the postpartum brain in the MPOA, lateral hypothalamus, and two subregions of PVN. Together, these findings indicate that endogenous changes occur in NT and its receptors across multiple brain regions, and these likely support the emergence of some maternal behaviors.
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Affiliation(s)
- Terri M. Driessen
- Department of Zoology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- * E-mail:
| | - Changjiu Zhao
- Department of Zoology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Anna Whittlinger
- Department of Zoology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Horecia Williams
- Department of Animal Science, Fort Valley State University, Fort Valley, Georgia, United States of America
| | - Stephen C. Gammie
- Department of Zoology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Neuroscience Training Program, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
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70
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Nakamura Y, Ishii J, Kondo A. Bright fluorescence monitoring system utilizing Zoanthus sp. green fluorescent protein (ZsGreen) for human G-protein-coupled receptor signaling in microbial yeast cells. PLoS One 2013; 8:e82237. [PMID: 24340008 PMCID: PMC3855394 DOI: 10.1371/journal.pone.0082237] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Accepted: 10/22/2013] [Indexed: 11/18/2022] Open
Abstract
G-protein-coupled receptors (GPCRs) are currently the most important pharmaceutical targets for drug discovery because they regulate a wide variety of physiological processes. Consequently, simple and convenient detection systems for ligands that regulate the function of GPCR have attracted attention as powerful tools for new drug development. We previously developed a yeast-based fluorescence reporter ligand detection system using flow cytometry. However, using this conventional detection system, fluorescence from a cell expressing GFP and responding to a ligand is weak, making detection of these cells by fluorescence microscopy difficult. We here report improvements to the conventional yeast fluorescence reporter assay system resulting in the development of a new highly-sensitive fluorescence reporter assay system with extremely bright fluorescence and high signal-to-noise (S/N) ratio. This new system allowed the easy detection of GPCR signaling in yeast using fluorescence microscopy. Somatostatin receptor and neurotensin receptor (implicated in Alzheimer's disease and Parkinson's disease, respectively) were chosen as human GPCR(s). The facile detection of binding to these receptors by cognate peptide ligands was demonstrated. In addition, we established a highly sensitive ligand detection system using yeast cell surface display technology that is applicable to peptide screening, and demonstrate that the display of various peptide analogs of neurotensin can activate signaling through the neurotensin receptor in yeast cells. Our system could be useful for identifying lead peptides with agonistic activity towards targeted human GPCR(s).
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Affiliation(s)
- Yasuyuki Nakamura
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, Kobe, Japan
| | - Jun Ishii
- Organization of Advanced Science and Technology, Kobe University, Kobe, Japan
| | - Akihiko Kondo
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, Kobe, Japan
- * E-mail:
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71
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Ahrabi NZ, Erfani M, Parivar K, Beiki D, Jalilian AR. Preparation and evaluation of a new neurotensin analog labeled with 99mTc for targeted imaging of neurotensin receptor positive tumors. J Radioanal Nucl Chem 2013. [DOI: 10.1007/s10967-013-2795-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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72
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Tanaka M, Nakao N, Yamamoto I, Tsushima N, Ohta Y. Changes in expression levels of neurotensin precursor and receptor mRNA in chicken intestinal tissues and liver during late embryonic and early posthatching development. Poult Sci 2013; 92:2765-71. [DOI: 10.3382/ps.2012-02939] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
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73
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Transient and stable expression of the neurotensin receptor NTS1: a comparison of the baculovirus-insect cell and the T-REx-293 expression systems. PLoS One 2013; 8:e63679. [PMID: 23696845 PMCID: PMC3656039 DOI: 10.1371/journal.pone.0063679] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Accepted: 04/05/2013] [Indexed: 01/06/2023] Open
Abstract
Nowadays, baculovirus-infected insect cells and tetracycline-inducible mammalian cell lines (T-REx-293) are intensively used for G protein-coupled receptor (GPCR) production for crystallography purposes. Here we constructed a suspension T-REx-293 cell line to stably express an engineered neurotensin receptor 1 (NTS1) mutant and we quantitatively compared this cell line with the transient baculovirus-insect cell system throughout a milligram-scale NTS1 expression and purification process. The two systems were comparable with respect to functional NTS1 expression levels and receptor binding affinity for the agonist [3H] neurotensin. However, NTS1 surface display on T-REx-293 cells determined by radio-ligand binding assays was 2.8 fold higher than that on insect cells. This work demonstrates two approaches for preparing milligram quantities of purified NTS1 suitable for structural studies and provides useful input to users in choosing and optimizing an appropriate expression host for other GPCRs.
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74
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Held C, Hübner H, Kling R, Nagel YA, Wennemers H, Gmeiner P. Impact of the Proline Residue on Ligand Binding of Neurotensin Receptor 2 (NTS2)-Selective Peptide-Peptoid Hybrids. ChemMedChem 2013; 8:772-8. [DOI: 10.1002/cmdc.201300054] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Indexed: 01/07/2023]
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75
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Neurotensin and neurotensin receptors: characteristic, structure-activity relationship and pain modulation--a review. Eur J Pharmacol 2013; 716:54-60. [PMID: 23500196 DOI: 10.1016/j.ejphar.2013.03.004] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Revised: 02/23/2013] [Accepted: 03/03/2013] [Indexed: 12/14/2022]
Abstract
Neurotensin (NT) is a tridecapeptide, which - since its discovery in 1973--has been demonstrated to be involved in the control of various physiological activities in both the central nervous system and in the periphery. Its biological effects are mediated by four receptor types. Exogenously administered NT exerts different behavioral effects, including antinociception. Structure-activity relationship studies performed in recent years resulted in development of several peptidomimetic receptor agonists and non-peptidic receptor antagonists that are useful tools for studies of NT mechanisms in tissue and on cellular level. This may result in design of new generation of analgesics based on neurotensin. NT antinociceptive effects are distinct from opioid analgesia. This creates opportunity of development of hybride analgesics that may simultaneously activate both opioid and NT antinociceptive pathways.
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76
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Inagaki S, Ghirlando R, Grisshammer R. Biophysical characterization of membrane proteins in nanodiscs. Methods 2013; 59:287-300. [PMID: 23219517 PMCID: PMC3608844 DOI: 10.1016/j.ymeth.2012.11.006] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Revised: 11/20/2012] [Accepted: 11/23/2012] [Indexed: 12/25/2022] Open
Abstract
Nanodiscs are self-assembled discoidal phospholipid bilayers surrounded and stabilized by membrane scaffold proteins (MSPs), that have become a powerful and promising tool for the study of membrane proteins. Even though their reconstitution is highly regulated by the type of MSP and phospholipid input, a biophysical characterization leading to the determination of the stoichiometry of MSP, lipid and membrane protein is essential. This is important for biological studies, as the oligomeric state of membrane proteins often correlates with their functional activity. Typically combinations of several methods are applied using, for example, modified samples that incorporate fluorescent labels, along with procedures that result in nanodisc disassembly and lipid dissolution. To obtain a comprehensive understanding of the native properties of nanodiscs, modification-free analysis methods are required. In this work we provide a strategy, using a combination of dynamic light scattering and analytical ultracentrifugation, for the biophysical characterization of unmodified nanodiscs. In this manner we characterize the nanodisc preparation in terms of its overall polydispersity and characterize the hydrodynamically resolved nanodisc of interest in terms of its sedimentation coefficient, Stokes' radius and overall protein and lipid stoichiometry. Functional and biological applications are also discussed for the study of the membrane protein embedded in nanodiscs under defined experimental conditions.
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Affiliation(s)
- Sayaka Inagaki
- Membrane Protein Structure Function Unit, National Institute of Neurological Disorders and Stroke, 5625 Fishers Lane, Room 4S12, Rockville, Maryland 20852, USA
| | - Rodolfo Ghirlando
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Building 5, Room 208, 5 Memorial Drive, Bethesda, Maryland, 20814, USA
| | - Reinhard Grisshammer
- Membrane Protein Structure Function Unit, National Institute of Neurological Disorders and Stroke, 5625 Fishers Lane, Room 4S12, Rockville, Maryland 20852, USA
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Shibata Y, Gvozdenovic-Jeremic J, Love J, Kloss B, White JF, Grisshammer R, Tate CG. Optimising the combination of thermostabilising mutations in the neurotensin receptor for structure determination. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:1293-301. [PMID: 23337476 DOI: 10.1016/j.bbamem.2013.01.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Revised: 01/07/2013] [Accepted: 01/09/2013] [Indexed: 10/27/2022]
Abstract
Conformational thermostabilisation of G protein-coupled receptors is a successful approach for their structure determination. We have recently determined the structure of a thermostabilised neurotensin receptor NTS1 in complex with its peptide agonist and here we describe the strategy for the identification and combination of the 6 thermostabilising mutations essential for crystallisation. First, thermostability assays were performed on a panel of 340 detergent-solubilised Ala/Leu NTS1 mutants and the best 16 thermostabilising mutations were identified. These mutations were combined pair-wise in nearly all combinations (119 out of a possible 120 combinations) and each mutant was expressed and its thermostability was experimentally determined. A theoretical stability score was calculated from the sum of the stabilities measured for each double mutant and applied to develop 24 triple mutants, which in turn led to the construction of 14 quadruple mutants. Use of the thermostability data for the double mutants to predict further mutant combinations resulted in a greater percentage of the triple and quadruple mutants showing improved thermostability than if only the thermostability data for the single mutations was considered. The best quadruple mutant (NTS1-Nag36k) was further improved by including an additional 2 mutations (resulting in NTS1-GW5) that were identified from a complete Ala/Leu scan of Nag36k by testing the thermostability of the mutants in situ in whole bacteria. NTS1-GW5 had excellent stability in short chain detergents and could be readily purified as a homogenous sample that ultimately allowed crystallisation and structure determination.
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Affiliation(s)
- Yoko Shibata
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, UK
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78
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Held C, Plomer M, Hübner H, Meltretter J, Pischetsrieder M, Gmeiner P. Development of a Metabolically Stable Neurotensin Receptor 2 (NTS2) Ligand. ChemMedChem 2012; 8:75-81. [DOI: 10.1002/cmdc.201200376] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Revised: 09/21/2012] [Indexed: 12/18/2022]
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79
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White JF, Noinaj N, Shibata Y, Love J, Kloss B, Xu F, Gvozdenovic-Jeremic J, Shah P, Shiloach J, Tate CG, Grisshammer R. Structure of the agonist-bound neurotensin receptor. Nature 2012; 490:508-13. [PMID: 23051748 PMCID: PMC3482300 DOI: 10.1038/nature11558] [Citation(s) in RCA: 393] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Accepted: 09/11/2012] [Indexed: 12/11/2022]
Abstract
Neurotensin (NT) is a 13 amino acid peptide that functions as both a neurotransmitter and a hormone through activation of the neurotensin receptor NTS1, a G protein-coupled receptor (GPCR). In the brain, NT modulates activity of dopaminergic systems, opioid-independent analgesia, and the inhibition of food intake, and in the gut NT regulates a range of digestive processes. Here we present the structure at 2.8 Å resolution of NTS1 in an active-like state, bound to NT8-13, the C terminal portion of NT responsible for agonist-induced activation of the receptor. The peptide agonist binds to NTS1 in an extended conformation nearly perpendicular to the membrane plane with the C-terminus oriented towards the receptor core. Our findings provide the first insight into the binding mode of a peptide agonist to a GPCR and may support the development of non-peptide ligands that could be useful in the treatment of neurological disorders, cancer and obesity.
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Affiliation(s)
- Jim F White
- Membrane Protein Structure Function Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Department of Health and Human Services, Rockville, Maryland 20852, USA
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GI functions of GPR39: novel biology. Curr Opin Pharmacol 2012; 12:647-52. [PMID: 22884904 DOI: 10.1016/j.coph.2012.07.019] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 07/24/2012] [Accepted: 07/27/2012] [Indexed: 01/20/2023]
Abstract
GPR39 is an orphan GPCR receptor belonging to the ghrelin/motilin receptor subfamily. The receptor is constitutively active and Zn(2+) is a physiological agonist of GPR39. The receptor is emerging as an important regulator of gastrointestinal motility and secretion. Although GPR39 does not seem to be involved in the regulation of food intake, contradictory results are available on the role of GPR39 in the regulation of body weight. A well-established stimulatory role for GPR39 has been defined in insulin secretion which makes the receptor an attractive target for the treatment of type 1 or 2 diabetes. GPR39 signaling also inhibits apoptosis and mediates neural synaptic signaling. Novel ligands of GPR39 are warranted to reveal the main physiological role of this receptor.
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81
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Griebel G, Holsboer F. Neuropeptide receptor ligands as drugs for psychiatric diseases: the end of the beginning? Nat Rev Drug Discov 2012; 11:462-78. [PMID: 22596253 DOI: 10.1038/nrd3702] [Citation(s) in RCA: 142] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The search for novel drugs for treating psychiatric disorders is driven by the growing medical need to improve on the effectiveness and side-effect profile of currently available therapies. Given the wealth of preclinical data supporting the role of neuropeptides in modulating behaviour, pharmaceutical companies have been attempting to target neuropeptide receptors for over two decades. However, clinical studies with synthetic neuropeptide ligands have been unable to confirm the promise predicted by studies in animal models. Here, we analyse preclinical and clinical results for neuropeptide receptor ligands that have been studied in clinical trials for psychiatric diseases, including agents that target the receptors for tachykinins, corticotropin-releasing factor, vasopressin and neurotensin, and suggest new ways to exploit the full potential of these candidate drugs.
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Affiliation(s)
- Guy Griebel
- Sanofi, Exploratory Unit, 91385 Chilly-Mazarin, France.
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82
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Fani M, Maecke HR, Okarvi SM. Radiolabeled peptides: valuable tools for the detection and treatment of cancer. Am J Cancer Res 2012; 2:481-501. [PMID: 22737187 PMCID: PMC3364555 DOI: 10.7150/thno.4024] [Citation(s) in RCA: 216] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Accepted: 03/31/2012] [Indexed: 12/17/2022] Open
Abstract
Human cancer cells overexpress many peptide receptors as molecular targets. Radiolabeled peptides that bind with high affinity and specificity to the receptors on tumor cells hold great potential for both diagnostic imaging and targeted radionuclide therapy. The advantage of solid-phase peptide synthesis, the availability of different chelating agents and prosthetic groups and bioconjugation techniques permit the facile preparation of a wide variety of peptide-based targeting molecules with diverse biological and tumor targeting properties. Some of these peptides, including somatostatin, bombesin, vasoactive intestinal peptide, gastrin, neurotensin, exendin and RGD are currently under investigation. It is anticipated that in the near future many of these peptides may find applications in nuclear oncology. This article presents recent developments in the field of small peptides, and their applications in the diagnosis and treatment of cancer.
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83
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Lee J, Kim YD, Park CG, Kim MY, Chang IY, Zuo DC, Shahi PK, Choi S, Yeum CH, Jun JY. Neurotensin modulates pacemaker activity in interstitial cells of Cajal from the mouse small intestine. Mol Cells 2012; 33:509-16. [PMID: 22441675 PMCID: PMC3887726 DOI: 10.1007/s10059-012-2290-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Revised: 02/23/2012] [Accepted: 02/24/2012] [Indexed: 01/25/2023] Open
Abstract
Neurotensin, a tridecapeptide localized in the gut to discrete enteroendocrine cells of the small bowel mucosa, is a hormone that plays an important role in gastrointestinal secretion, growth, and motility. Neurotensin has inhibitory and excitatory effects on peristaltic activity and produces contractile and relaxant responses in intestinal smooth muscle. Our objective in this study is to investigate the effects of neurotensin in small intestinal interstitial cells of Cajal (ICC) and elucidate the mechanism. To determine the electrophysiological effects of neurotensin on ICC, whole-cell patch clamp recordings were performed in cultured ICC from the small intestine. Exposure to neurotensin depolarized the membrane of pacemaker cells and produced tonic inward pacemaker currents. Only neurotensin receptor1 was identified when RT-PCR and immunocytochemistry were performed with mRNA isolated from small intestinal ICC and c-Kit positive cells. Neurotensin-induced tonic inward pacemaker currents were blocked by external Na⁺-free solution and in the presence of flufenamic acid, an inhibitor of non-selective cation channels. Furthermore, neurotensin-induced action is blocked either by treatment with U73122, a phospholipase C inhibitor, or thapsigargin, a Ca²⁺-ATPase inhibitor in ICC. We found that neurotensin increased spontaneous intracellular Ca²⁺ oscillations as seen with fluo4/AM recording. These results suggest that neurotensin modulates pacemaker currents via the activation of non-selective cation channels by intracellular Ca²⁺-release through neurotensin receptor1.
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Affiliation(s)
| | | | | | | | | | - Dong Chuan Zuo
- Department of Physiology, College of Medicine, Chosun University, Gwangju 501-759,
Korea
| | - Pawan Kumar Shahi
- Department of Physiology, College of Medicine, Chosun University, Gwangju 501-759,
Korea
| | - Seok Choi
- Department of Physiology, College of Medicine, Chosun University, Gwangju 501-759,
Korea
| | - Cheol Ho Yeum
- Department of Physiology, College of Medicine, Chosun University, Gwangju 501-759,
Korea
| | - Jae Yeoul Jun
- Department of Physiology, College of Medicine, Chosun University, Gwangju 501-759,
Korea
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84
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Law IKM, Murphy JE, Bakirtzi K, Bunnett NW, Pothoulakis C. Neurotensin-induced proinflammatory signaling in human colonocytes is regulated by β-arrestins and endothelin-converting enzyme-1-dependent endocytosis and resensitization of neurotensin receptor 1. J Biol Chem 2012; 287:15066-75. [PMID: 22416137 DOI: 10.1074/jbc.m111.327262] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The neuropeptide/hormone neurotensin (NT) mediates intestinal inflammation and cell proliferation by binding of its high affinity receptor, neurotensin receptor-1 (NTR1). NT stimulates IL-8 expression in NCM460 human colonic epithelial cells by both MAP kinase- and NF-κB-dependent pathways. Although the mechanism of NTR1 endocytosis has been studied, the relationship between NTR1 intracellular trafficking and inflammatory signaling remains to be elucidated. In the present study, we show that in NCM460 cells exposed to NT, β-arrestin-1 (βARR1), and β-arrestin-2 (βARR2) translocate to early endosomes together with NTR1. Endothelin-converting enzyme-1 (ECE-1) degrades NT in acidic conditions, and its activity is crucial for NTR1 recycling. Pretreatment of NCM460 cells with the ECE-1 inhibitor SM19712 or gene silencing of βARR1 or βARR2 inhibits NT-stimulated ERK1/2 and JNK phosphorylation, NF-κB p65 nuclear translocation and phosphorylation, and IL-8 secretion. Furthermore, NT-induced cell proliferation, but not IL-8 transcription, is attenuated by the JNK inhibitor, JNK(AII). Thus, NTR1 internalization and recycling in human colonic epithelial cells involves βARRs and ECE-1, respectively. Our results also indicate that βARRs and ECE-1-dependent recycling regulate MAP kinase and NF-κB signaling as well as cell proliferation in human colonocytes in response to NT.
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Affiliation(s)
- Ivy Ka Man Law
- Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California 90095-7019, USA
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85
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Lewis RJ, Dutertre S, Vetter I, Christie MJ. Conus Venom Peptide Pharmacology. Pharmacol Rev 2012; 64:259-98. [DOI: 10.1124/pr.111.005322] [Citation(s) in RCA: 323] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
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86
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Inagaki S, Ghirlando R, White JF, Gvozdenovic-Jeremic J, Northup JK, Grisshammer R. Modulation of the interaction between neurotensin receptor NTS1 and Gq protein by lipid. J Mol Biol 2012; 417:95-111. [PMID: 22306739 DOI: 10.1016/j.jmb.2012.01.023] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Revised: 01/09/2012] [Accepted: 01/13/2012] [Indexed: 12/11/2022]
Abstract
Membrane lipids have been implicated to influence the activity of G-protein-coupled receptors (GPCRs). Almost all of our knowledge on the role of lipids on GPCR and G protein function comes from work on the visual pigment rhodopsin and its G protein transducin, which reside in a highly specialized membrane environment. Thus, insight gained from rhodopsin signaling may not be simply translated to other nonvisual GPCRs. Here, we investigated the effect of lipid head group charges on the signal transduction properties of the class A GPCR neurotensin (NT) receptor 1 (NTS1) under defined experimental conditions, using self-assembled phospholipid nanodiscs prepared with the zwitter-ionic lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), the negatively charged 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (POPG), or a POPC/POPG mixture. A combination of dynamic light scattering and sedimentation velocity showed that NTS1 was monomeric in POPC-, POPC/POPG-, and POPG-nanodiscs. Binding of the agonist NT to NTS1 occurred with similar affinities and was essentially unaffected by the phospholipid composition. In contrast, Gq protein coupling to NTS1 in various lipid nanodiscs was significantly different, and the apparent affinity of Gαq and Gβ(1)γ(1) to activated NTS1 increased with increasing POPG content. NTS1-catalyzed GDP/GTPγS nucleotide exchange at Gαq in the presence of Gβ(1)γ(1) and NT was crucially affected by the lipid type, with exchange rates higher by 1 or 2 orders of magnitude in POPC/POPG- and POPG-nanodiscs, respectively, compared to POPC-nanodiscs. Our data demonstrate that negatively charged lipids in the immediate vicinity of a nonvisual GPCR modulate the G-protein-coupling step.
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Affiliation(s)
- Sayaka Inagaki
- Membrane Protein Structure Function Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Department of Health and Human Services, Rockville, MD 20852, USA
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87
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Wu Z, Martinez-Fong D, Trédaniel J, Forgez P. Neurotensin and its high affinity receptor 1 as a potential pharmacological target in cancer therapy. Front Endocrinol (Lausanne) 2012; 3:184. [PMID: 23335914 PMCID: PMC3547287 DOI: 10.3389/fendo.2012.00184] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Accepted: 12/26/2012] [Indexed: 12/12/2022] Open
Abstract
Cancer is a worldwide health problem. Personalized treatment represents a future advancement for cancer treatment, in part due to the development of targeted therapeutic drugs. These molecules are expected to be more effective than current treatments and less harmful to normal cells. The discovery and validation of new targets are the foundation and the source of these new therapies. The neurotensinergic system has been shown to enhance cancer progression in various cancers such as pancreatic, prostate, lung, breast, and colon cancer. It also triggers multiple oncogenic signaling pathways, such as the PKC/ERK and AKT pathways. In this review, we discuss the contribution of the neurotensinergic system to cancer progression, as well as the regulation and mechanisms of the system in order to highlight its potential as a therapeutic target, and its prospect for its use as a treatment in certain cancers.
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Affiliation(s)
- Zherui Wu
- INSERM-UPMC UMR_S938, Hôpital Saint-AntoineParis, France
| | - Daniel Martinez-Fong
- Departamento de Fisiologïa, Biofïsica y Neurociencias, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalMexico City, Mexico
| | - Jean Trédaniel
- INSERM-UPMC UMR_S938, Hôpital Saint-AntoineParis, France
- Unité de Cancérologie Thoracique, Groupe Hospitalier Paris Saint-Joseph/Université Paris DescartesParis, France
| | - Patricia Forgez
- INSERM-UPMC UMR_S938, Hôpital Saint-AntoineParis, France
- *Correspondence: Patricia Forgez, INSERM-UPMC UMR_S938, Hôpital Saint-Antoine, Bâtiment Raoul Kourilsky, 184 rue du Faubourg St-Antoine, 75571 Paris Cedex 12, France. e-mail:
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88
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Gammie SC, Lee G, Scotti MAL, Stevenson SA, Gessay GM. Neurotensin induced Egr-1 activity is altered in the postpartum period in mice. Brain Res 2011; 1433:47-55. [PMID: 22138429 DOI: 10.1016/j.brainres.2011.11.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 10/26/2011] [Accepted: 11/05/2011] [Indexed: 11/19/2022]
Abstract
Neurotensin (NT) is a 13 amino acid neuropeptide that is identical in mice and humans and is released from and acts upon a number of social brain regions. Recent work indicates NT neurotransmission may be altered in postpartum females and support the onset of some maternal behaviors. In a recent study, we highlighted how virgin and postpartum brains from mice selected for high offspring protection differ in response to injected NT (0.1 μg) relative to vehicle when examining c-Fos profiles across the CNS. In this companion study we use a second marker for brain activity, Egr-1, and evaluate multiple brain regions. Common significant increased Egr-1 responses to NT (relative to vehicle) were found in both female groups only in ventromedial hypothalamus. In lateral periaqueductal gray, virgin mice showed a significant Egr-1 increase with NT (relative to vehicle), but maternal mice did not. When comparing NT injections, virgin (relative to maternal) mice had significantly higher activity in five regions, including anterior hypothalamus, lateral hypothalamus, somatosensory cortex, paraventricular nucleus, and zona incerta; no regions were higher in maternal mice. A Principal Components Analysis was also used for data mining and in virgin mice, greater changes in activity hubs were found with NT (relative to vehicle) than for maternal mice. Overall, a lower sensitivity to NT in terms of Egr-1 reactivity in the maternal state was highlighted and this is consistent with previous c-Fos results. These findings provide additional insight into the mechanisms by which NT functions in the CNS.
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Affiliation(s)
- Stephen C Gammie
- Department of Zoology, University of Wisconsin, Madison, WI, USA.
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89
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Sahlholm K. The role of RGS protein in agonist-dependent relaxation of GIRK currents in Xenopus oocytes. Biochem Biophys Res Commun 2011; 415:509-14. [PMID: 22068057 DOI: 10.1016/j.bbrc.2011.10.106] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Accepted: 10/22/2011] [Indexed: 01/28/2023]
Abstract
G protein coupled inward rectifier K(+) channels (GIRK) are activated by the G(βγ) subunits of G proteins upon activation of G protein coupled receptors (GPCRs). Receptor-stimulated GIRK currents are known to possess a curious property, termed "agonist-dependent relaxation," denoting a slow current increase upon stepping the membrane voltage from positive to negative potentials. Regulators of G protein signaling (RGS) proteins have earlier been implicated in this phenomenon since RGS coexpression was required for relaxation to be observed in heterologous expression systems. However, a recent study presented contrasting evidence that GIRK current relaxation reflects voltage sensitive agonist binding to the GPCR. The present study re-examined the role of RGS protein in agonist-dependent relaxation and found that RGS coexpression is not necessary for the relaxation phenomenon. However, RGS4 speeds up relaxation kinetics, allowing the phenomenon to be observed using shorter voltage steps. These findings resolve the controversy regarding the role of RGS protein vs. GPCR voltage sensitivity in mediating agonist-dependent relaxation of GIRK currents.
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Affiliation(s)
- Kristoffer Sahlholm
- Department of Neuroscience, Karolinska Institutet, 171 77 Stockholm, Sweden.
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90
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Effects of pallidal neurotensin on haloperidol-induced parkinsonian catalepsy: behavioral and electrophysiological studies. Neurosci Bull 2011; 26:345-54. [PMID: 20882060 DOI: 10.1007/s12264-010-0518-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
OBJECTIVE The globus pallidus plays a critical role in movement regulation. Previous studies have indicated that the globus pallidus receives neurotensinergic innervation from the striatum, and systemic administration of a neurotensin analog could produce antiparkinsonian effects. The present study aimed to investigate the effects of pallidal neurotensin on haloperidol-induced parkinsonian symptoms. METHODS Behavioral experiments and electrophysiological recordings were performed in the present study. RESULTS Bilateral infusions of neurotensin into the globus pallidus reversed haloperidol-induced parkinsonian catalepsy in rats. Electrophysiological recordings showed that microinjection of neurotensin induced excitation of pallidal neurons in the presence of systemic haloperidol administration. The neurotensin type-1 receptor antagonist SR48692 blocked both the behavioral and the electrophysiological effects induced by neurotensin. CONCLUSION Activation of pallidal neurotensin receptors may be involved in neurotensin-induced antiparkinsonian effects.
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91
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Scotti MAL, Stevenson SA, Gammie SC. Changes in CNS response to neurotensin accompany the postpartum period in mice. Horm Behav 2011; 60:177-84. [PMID: 21554882 DOI: 10.1016/j.yhbeh.2011.04.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Revised: 04/18/2011] [Accepted: 04/19/2011] [Indexed: 10/18/2022]
Abstract
Neurotensin (NT) is a highly conserved neuropeptide in mammals. Recent studies suggest that altered NT neurotransmission in postpartum females could promote the emergence of some maternal behaviors, including offspring protection. Here we evaluated how virgin and postpartum brains from mice selected for high maternal defense differ in response to NT. Virgin and postpartum mice were injected with either vehicle or 0.1 μg NT icv and brains were evaluated for c-Fos immunoreactivity, an indirect marker of neuronal activity. Using ANOVA analysis, common significant responses to NT were found in both female groups in four brain regions, including supraoptic nucleus, ventromedial nucleus, bed nucleus of stria terminalis dorsal, and a subregion of lateral septum (LS). For postpartum mice, only one additional region showed a significant response to NT relative to vehicle, whereas for virgin mice seven unique brain regions showed a significant c-Fos response: nucleus accumbens shell, paraventricular nucleus, central amygdala, and substantia nigra. Using a principal components analysis of c-Fos, we identified regions within each group with highly correlated activity. As expected, virgin and postpartum mice (vehicle conditions) showed different activity hubs and in the postpartum group the hubs matched regions linked to maternal care. The response to injected NT was different in the maternal and virgin groups with maternal mice showing a stronger coordinated activity in periaqueductal gray whereas virgin mice showed a stronger septal and amygdala linking of activity. Together, these results indicate neuronal responses of virgin and postpartum mice to NT and highlight pathways by which NT can alter maternal responses.
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92
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Podstawka-Proniewicz E, Kudelski A, Kim Y, Proniewicz LM. Structure and Binding of Specifically Mutated Neurotensin Fragments on a Silver Substrate: Vibrational Studies. J Phys Chem B 2011; 115:7097-108. [DOI: 10.1021/jp201316n] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
| | - Andrzej Kudelski
- Faculty of Chemistry, University of Warsaw, ul. L. Pasteura 1, 02-093 Warsaw, Poland
| | - Younkyoo Kim
- Department of Chemistry, Hankuk University of Foreign Studies, Yongin, Kyunggi-Do 449-791, Korea
| | - Leonard M. Proniewicz
- Faculty of Chemistry, Jagiellonian University, ul. Ingardena 3, 30-060 Krakow, Poland
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93
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Podstawka-Proniewicz E, Kudelski A, Kim Y, Proniewicz LM. Structure of monolayers formed from neurotensin and its single-site mutants: vibrational spectroscopic studies. J Phys Chem B 2011; 115:6709-21. [PMID: 21542591 DOI: 10.1021/jp200805f] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The human, pig, and frog neurotensins and four single-site mutants of human neurotensin (NT), having the following modifications, [Gln(4)]NT, [Trp(11)]NT, [D-Trp(11)]NT, and [D-Tyr(11)]NT, were immobilized onto an electrochemically roughened silver electrode surface in an aqueous solution. The orientation of adsorbed molecules was determined from surface-enhanced Raman scattering (SERS) measurements. A comparison was made between these structures to determine how the change upon the mutation of the neurotensin structure influences its adsorption properties. The SERS patterns were correlated with the contribution of the structural components of the aforementioned peptides to the ability to interact with the NTR1 G-protein receptor. Briefly, the SERS spectra revealed that the substitution of native amino acids in investigated peptides influenced slightly their adsorption state on an electrochemically roughened silver surface. Thus, human, pig, and frog neurotensins and [Gln(4)]NT and [D-Tyr(11)]NT tended to adsorb to the surface via the tyrosine ring, the oxygen atom of the deprotonated phenol group of Tyr(11), and the -CH(2)- unit(s), most probably of Tyr(11), Arg(9), and/or Leu(13). The observed changes in the enhancement of the deprotonated Tyr residue SERS signals indicated a further parallel orientation of a phenol-O bond with regard to the silver surface normal for pig NT, [Gln(4)]NT, and [D-Tyr(11)]NT, whereas the orientation was slightly tilted for human and frog NT. In the case of [Trp(11)]NT and [D-Trp(11)]NT, the formation of a peptide/Ag complex was confirmed by strong SERS bands involving the phenyl co-ring of Trp(11)/d-Trp(11) and -CH(2)- vibrations and the tilted and flat orientations of the two compounds with respect to the surface substrate. The spectral features were accompanied by a SERS signal caused by vibrations of the carboxyl group of C-terminal Leu(13) and the guanidine group of Arg(9). Reported changes in SERS spectra of L and D isomers were fully supported by generalized two-dimensional correlation analysis. Additionally, a combination of mutation-labeling and vibrational spectroscopy (Fourier-transform Raman and absorption infrared) was used to investigate the possible peptide conformations and environments of the tyrosine residues.
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94
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Wang JG, Li NN, Li HN, Cui L, Wang P. Pancreatic cancer bears overexpression of neurotensin and neurotensin receptor subtype-1 and SR 48692 counteracts neurotensin induced cell proliferation in human pancreatic ductal carcinoma cell line PANC-1. Neuropeptides 2011; 45:151-6. [PMID: 21272935 DOI: 10.1016/j.npep.2011.01.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Revised: 01/03/2011] [Accepted: 01/03/2011] [Indexed: 01/22/2023]
Abstract
The presence of neurotensin and neurotensin receptors has been demonstrated in human pancreatic carcinomas using autoradiography and Northern blot analysis. In vitro studies have reported that the neurotensin antagonist SR 48692 could inhibit the growth of MIA PaCa-2 cells in a neurotensin mediated fashion, and neurotensin could overcome this inhibition or stimulate proliferation. However, it is currently unknown whether such actions are exerted on PANC-1 cells. In addition, the immunolocation of neurotensin and neurotensin receptors is still unclear in human pancreatic ductal carcinoma tissues. Immunohistochemistry was applied to detect the distribution of neurotensin and neurotensin receptor subtype-1 in human pancreatic ductal carcinoma and normal pancreatic tissues. Furthermore, an in vitro study was carried out to test the pharmacological profile of neurotensin and SR 48692 in human pancreatic ductal carcinoma cell line PANC-1. Compared with normal pancreatic tissues, pancreatic ductal carcinoma tissues have higher neurotensin and neurotensin receptor subtype-1 expression rates. Pancreatic ductal carcinomas (32/40) bear the expression of both neurotensin and neurotensin receptor subtype-1. We observed that neurotensin (10⁻¹¹-10⁻⁷ M) significantly stimulated the proliferation of PANC-1 and SR 48692 (10⁻¹¹-10⁻⁷ M) alone had no effect on the growth of PANC-1 cells; however, SR 48692 (10⁻¹⁰-10⁻⁶ M) inhibited the stimulatory effect of neurotensin (10⁻⁹ M). Considering the overexpression of both neurotensin and neurotensin receptor subtype-1 in pancreatic ductal carcinomas, it could enable us to develop markers for pancreatic cancer diagnosis. As SR 48692 could inhibit neurotensin induced cell growth, neurotensin receptor subtype-1 may serve as a therapeutic target for the therapy of pancreatic carcinomas. Furthermore, our study indicates that the counteraction of neurotensin and neurotensin receptor subtype-1 regulates the genesis and development of pancreatic carcinomas.
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Affiliation(s)
- Ji-Gang Wang
- Department of Pathology, The Affiliated Hospital of Medical College, Qingdao University, 16 Jiangsu Road, Qingdao, Shandong 266003, China
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95
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Einsiedel J, Held C, Hervet M, Plomer M, Tschammer N, Hübner H, Gmeiner P. Discovery of Highly Potent and Neurotensin Receptor 2 Selective Neurotensin Mimetics. J Med Chem 2011; 54:2915-23. [DOI: 10.1021/jm200006c] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Jürgen Einsiedel
- Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich Alexander University, Schuhstrasse 19, 91052 Erlangen, Germany
| | - Cornelia Held
- Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich Alexander University, Schuhstrasse 19, 91052 Erlangen, Germany
| | - Maud Hervet
- Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich Alexander University, Schuhstrasse 19, 91052 Erlangen, Germany
| | - Manuel Plomer
- Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich Alexander University, Schuhstrasse 19, 91052 Erlangen, Germany
| | - Nuska Tschammer
- Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich Alexander University, Schuhstrasse 19, 91052 Erlangen, Germany
| | - Harald Hübner
- Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich Alexander University, Schuhstrasse 19, 91052 Erlangen, Germany
| | - Peter Gmeiner
- Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich Alexander University, Schuhstrasse 19, 91052 Erlangen, Germany
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96
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Numao M, Sudo H, Yamamoto I, Nakao N, Kaiya H, Miyazato M, Tsushima N, Tanaka M. Molecular characterization of structure and tissue distribution of chicken neurotensin receptor. Gen Comp Endocrinol 2011; 171:33-8. [PMID: 21199657 DOI: 10.1016/j.ygcen.2010.12.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2010] [Revised: 12/14/2010] [Accepted: 12/29/2010] [Indexed: 01/17/2023]
Abstract
Neurotensin, a tridecapeptide, is distributed in a wide range of tissues and exhibits multiple functions through its receptors. Hitherto molecular characterization of the neurotensin receptor has been reported in mammalian, amphibian, and fish species but not in avian species. In this study, we cloned the cDNA encoding chicken neurotensin receptor from the duodenum and characterized its primary structure, biological activity and distribution in the gastrointestinal tract. The cDNA encoded a protein consisting of 399 amino acids that had significant overall sequence homology to other vertebrate neurotensin receptor 1 with higher extent in the seven transmembrane domains. Chicken neurotensin increased intracellular Ca(2+) concentrations in human embryonic kidney 293 cells transiently expressing the chicken neurotensin receptor 1. Real-time PCR analysis showed that chicken neurotensin receptor 1 mRNA is expressed throughout the gastrointestinal tract with markedly higher level in the colon/rectum. These results indicate that the chicken neurotensin receptor 1 is involved in gastrointestinal functions through an intracellular signaling pathway accompanied by an increase in Ca(2+) levels.
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Affiliation(s)
- Makoto Numao
- Department of Animal Science, Faculty of Applied Life Science, Nippon Veterinary and Life Science University, Musashino, Tokyo 180-8602, Japan
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97
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Robertson CR, Flynn SP, White HS, Bulaj G. Anticonvulsant neuropeptides as drug leads for neurological diseases. Nat Prod Rep 2011; 28:741-62. [PMID: 21340067 DOI: 10.1039/c0np00048e] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Anticonvulsant neuropeptides are best known for their ability to suppress seizures and modulate pain pathways. Galanin, neuropeptide Y, somatostatin, neurotensin, dynorphin, among others, have been validated as potential first-in-class anti-epileptic or/and analgesic compounds in animal models of epilepsy and pain, but their therapeutic potential extends to other neurological indications, including neurodegenerative and psychatric disorders. Disease-modifying properties of neuropeptides make them even more attractive templates for developing new-generation neurotherapeutics. Arguably, efforts to transform this class of neuropeptides into drugs have been limited compared to those for other bioactive peptides. Key challenges in developing neuropeptide-based anticonvulsants are: to engineer optimal receptor-subtype selectivity, to improve metabolic stability and to enhance their bioavailability, including penetration across the blood–brain barrier (BBB). Here, we summarize advances toward developing systemically active and CNS-penetrant neuropeptide analogs. Two main objectives of this review are: (1) to provide an overview of structural and pharmacological properties for selected anticonvulsant neuropeptides and their analogs and (2) to encourage broader efforts to convert these endogenous natural products into drug leads for pain, epilepsy and other neurological diseases.
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Affiliation(s)
- Charles R Robertson
- College of Pharmacy, Department of Medicinal Chemistry, 421 Wakara Way, STE. 360 Salt Lake City, UT 84108, USA
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98
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Tapaneeyakorn S, Ross S, Attrill H, Watts A. Heterologous high yield expression and purification of neurotensin and its functional fragment in Escherichia coli. Protein Expr Purif 2010; 74:65-8. [DOI: 10.1016/j.pep.2010.06.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2010] [Revised: 06/24/2010] [Accepted: 06/28/2010] [Indexed: 11/29/2022]
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99
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Lee MR, Hinton DJ, Unal SS, Richelson E, Choi DS. Increased ethanol consumption and preference in mice lacking neurotensin receptor type 2. Alcohol Clin Exp Res 2010; 35:99-107. [PMID: 21039631 DOI: 10.1111/j.1530-0277.2010.01326.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Neurotensin receptors (NTS) regulate a variety of the biological functions of neurotensin (NT) in the central nervous system. Although NT and neurotensin receptors type 1 (NTS1) are implicated in some of the behavioral effects of ethanol, the functional roles of neurotensin receptors type 2 (NTS2) in ethanol intoxication and consumption remain unknown. Here, we investigated behavioral effects mediated by NTS2 in response to ethanol, which are implicated in ethanol consumption and preference, using NTS2 null mice. METHOD First, we examined ethanol-induced locomotion, ataxia, hypnosis, and hypothermia in NTS2 null mice. Next, we measured ethanol consumption and preference in NTS2 null mice by giving them free choice between ethanol- and tap water-containing bottles. Then using a brain-permeable NT analog, NT69L, we examined the role of NTS2 in locomotor activity and ataxia. Finally, we examined the effect of NT69L on ethanol consumption and preference in NTS2 null mice. RESULTS We found that NTS2 null mice appear less sensitive to the acute hypnotic effects of ethanol and consumed more ethanol compared to wild-type littermates in a 2-bottle choice experiment, even though ethanol-induced locomotion, ataxia, and hypothermia were similar between genotypes. Interestingly, the administration of NT69L for 4 consecutive days significantly reduced alcohol consumption and preference in wild-type littermates as well as in NTS2 null mice. CONCLUSIONS Our findings suggest that NTS2 regulates ethanol-induced hypnosis and ethanol consumption.
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Affiliation(s)
- Moonnoh R Lee
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, College of Medicine, Rochester, Minnesota 55905, USA
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100
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White JF, Grisshammer R. Stability of the neurotensin receptor NTS1 free in detergent solution and immobilized to affinity resin. PLoS One 2010; 5:e12579. [PMID: 20830205 PMCID: PMC2935352 DOI: 10.1371/journal.pone.0012579] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2010] [Accepted: 08/08/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Purification of recombinant membrane receptors is commonly achieved by use of an affinity tag followed by an additional chromatography step if required. This second step may exploit specific receptor properties such as ligand binding. However, the effects of multiple purification steps on protein yield and integrity are often poorly documented. We have previously reported a robust two-step purification procedure for the recombinant rat neurotensin receptor NTS1 to give milligram quantities of functional receptor protein. First, histidine-tagged receptors are enriched by immobilized metal affinity chromatography using Ni-NTA resin. Second, remaining contaminants in the Ni-NTA column eluate are removed by use of a subsequent neurotensin column yielding pure NTS1. Whilst the neurotensin column eluate contained functional receptor protein, we observed in the neurotensin column flow-through misfolded NTS1. METHODS AND FINDINGS To investigate the origin of the misfolded receptors, we estimated the amount of functional and misfolded NTS1 at each purification step by radio-ligand binding, densitometry of Coomassie stained SDS-gels, and protein content determination. First, we observed that correctly folded NTS1 suffers damage by exposure to detergent and various buffer compositions as seen by the loss of [(3)H]neurotensin binding over time. Second, exposure to the neurotensin affinity resin generated additional misfolded receptor protein. CONCLUSION Our data point towards two ways by which misfolded NTS1 may be generated: Damage by exposure to buffer components and by close contact of the receptor to the neurotensin affinity resin. Because NTS1 in detergent solution is stabilized by neurotensin, we speculate that the occurrence of aggregated receptor after contact with the neurotensin resin is the consequence of perturbations in the detergent belt surrounding the NTS1 transmembrane core. Both effects reduce the yield of functional receptor protein.
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Affiliation(s)
- Jim F. White
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Department of Health and Human Services, Rockville, Maryland, United States of America
| | - Reinhard Grisshammer
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Department of Health and Human Services, Rockville, Maryland, United States of America
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