1
|
Chemogenetic Enhancement of cAMP Signaling Renders Hippocampal Synaptic Plasticity Resilient to the Impact of Acute Sleep Deprivation. eNeuro 2023; 10:ENEURO.0380-22.2022. [PMID: 36635248 PMCID: PMC9829098 DOI: 10.1523/eneuro.0380-22.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 10/24/2022] [Accepted: 12/04/2022] [Indexed: 12/14/2022] Open
Abstract
Sleep facilitates memory storage and even brief periods of sleep loss lead to impairments in memory, particularly memories that are hippocampus dependent. In previous studies, we have shown that the deficit in memory seen after sleep loss is accompanied by deficits in synaptic plasticity. Our previous work has also found that sleep deprivation (SD) is associated with reduced levels of cyclic adenosine monophosphate (cAMP) in the hippocampus and that the reduction of cAMP mediates the diminished memory observed in sleep-deprived animals. Based on these findings, we hypothesized that cAMP acts as a mediator for not only the cognitive deficits caused by sleep deprivation, but also the observed deficits in synaptic plasticity. In this study, we expressed the heterologous Drosophila melanogaster Gαs-protein-coupled octopamine receptor (DmOctβ1R) in mouse hippocampal neurons. This receptor is selectively activated by the systemically injected ligand (octopamine), thus allowing us to increase cAMP levels in hippocampal neurons during a 5-h sleep deprivation period. Our results show that chemogenetic enhancement of cAMP during the period of sleep deprivation prevents deficits in a persistent form of long-term potentiation (LTP) that is induced at the Schaffer collateral synapses in the hippocampal CA1 region. We also found that elevating cAMP levels in either the first or second half of sleep deprivation successfully prevented LTP deficits. These findings reveal that cAMP-dependent signaling pathways are key mediators of sleep deprivation at the synaptic level. Targeting these pathways could be useful in designing strategies to prevent the impact of sleep loss.
Collapse
|
2
|
Puri S, Kenyon BM, Hamrah P. Immunomodulatory Role of Neuropeptides in the Cornea. Biomedicines 2022; 10:1985. [PMID: 36009532 PMCID: PMC9406019 DOI: 10.3390/biomedicines10081985] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 12/21/2022] Open
Abstract
The transparency of the cornea along with its dense sensory innervation and resident leukocyte populations make it an ideal tissue to study interactions between the nervous and immune systems. The cornea is the most densely innervated tissue of the body and possesses both immune and vascular privilege, in part due to its unique repertoire of resident immune cells. Corneal nerves produce various neuropeptides that have a wide range of functions on immune cells. As research in this area expands, further insights are made into the role of neuropeptides and their immunomodulatory functions in the healthy and diseased cornea. Much remains to be known regarding the details of neuropeptide signaling and how it contributes to pathophysiology, which is likely due to complex interactions among neuropeptides, receptor isoform-specific signaling events, and the inflammatory microenvironment in disease. However, progress in this area has led to an increase in studies that have begun modulating neuropeptide activity for the treatment of corneal diseases with promising results, necessitating the need for a comprehensive review of the literature. This review focuses on the role of neuropeptides in maintaining the homeostasis of the ocular surface, alterations in disease settings, and the possible therapeutic potential of targeting these systems.
Collapse
Affiliation(s)
- Sudan Puri
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Department of Ophthalmology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
| | - Brendan M. Kenyon
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Program in Neuroscience, Graduate School of Biomedical Sciences, Tufts University, Boston, MA 02111, USA
| | - Pedram Hamrah
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Department of Ophthalmology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Program in Neuroscience, Graduate School of Biomedical Sciences, Tufts University, Boston, MA 02111, USA
- Departments of Immunology and Neuroscience, Tufts University School of Medicine, Boston, MA 02111, USA
- Cornea Service, Tufts New England Eye Center, Boston, MA 02111, USA
| |
Collapse
|
3
|
Sánchez ML, Coveñas R. The Galaninergic System: A Target for Cancer Treatment. Cancers (Basel) 2022; 14:cancers14153755. [PMID: 35954419 PMCID: PMC9367524 DOI: 10.3390/cancers14153755] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 07/28/2022] [Accepted: 07/29/2022] [Indexed: 12/14/2022] Open
Abstract
Simple Summary Peptidergic systems play an important role in cancer progression. The galaninergic system (the peptide galanin and its receptors: galanin 1, 2 and 3) is involved in tumorigenesis, the invasion and migration of tumor cells and angiogenesis and it has been correlated with tumor stage/subtypes, metastasis and recurrence rate in many types of cancer. Galanin exerts a dual action in tumor cells: a proliferative or an antiproliferative effect depending on the galanin receptor involved in these mechanisms. Galanin receptors could be used in certain tumors as therapeutic targets and diagnostic markers for treatment, prognosis and surgical outcome. This review shows the importance of the galaninergic system in the development of tumors and suggests future promising clinical antitumor applications using galanin agonists or antagonists. Abstract The aim of this review is to show the involvement of the galaninergic system in neuroendocrine (phaeochromocytomas, insulinomas, neuroblastic tumors, pituitary tumors, small-cell lung cancer) and non-neuroendocrine (gastric cancer, colorectal cancer, head and neck squamous cell carcinoma, glioma) tumors. The galaninergic system is involved in tumorigenesis, invasion/migration of tumor cells and angiogenesis, and this system has been correlated with tumor size/stage/subtypes, metastasis and recurrence rate. In the galaninergic system, epigenetic mechanisms have been related with carcinogenesis and recurrence rate. Galanin (GAL) exerts both proliferative and antiproliferative actions in tumor cells. GAL receptors (GALRs) mediate different signal transduction pathways and actions, depending on the particular G protein involved and the tumor cell type. In general, the activation of GAL1R promoted an antiproliferative effect, whereas the activation of GAL2R induced antiproliferative or proliferative actions. GALRs could be used in certain tumors as therapeutic targets and diagnostic markers for treatment, prognosis and surgical outcome. The current data show the importance of the galaninergic system in the development of certain tumors and suggest future potential clinical antitumor applications using GAL agonists or antagonists.
Collapse
Affiliation(s)
- Manuel Lisardo Sánchez
- Laboratorio de Neuroanatomía de los Sistema Peptidérgicos (Lab. 14), Instituto de Neurociencias de Castilla y León (INCYL), Universidad de Salamanca, c/Pintor Fernando Gallego 1, 37007 Salamanca, Spain;
- Correspondence: ; Tel.: +34-923294400 (ext. 1856); Fax: +34-923294549
| | - Rafael Coveñas
- Laboratorio de Neuroanatomía de los Sistema Peptidérgicos (Lab. 14), Instituto de Neurociencias de Castilla y León (INCYL), Universidad de Salamanca, c/Pintor Fernando Gallego 1, 37007 Salamanca, Spain;
- Grupo GIR USAL: BMD (Bases Moleculares del Desarrollo), University of Salamanca, 37007 Salamanca, Spain
| |
Collapse
|
4
|
Hökfelt T, Barde S, Xu ZQD, Kuteeva E, Rüegg J, Le Maitre E, Risling M, Kehr J, Ihnatko R, Theodorsson E, Palkovits M, Deakin W, Bagdy G, Juhasz G, Prud’homme HJ, Mechawar N, Diaz-Heijtz R, Ögren SO. Neuropeptide and Small Transmitter Coexistence: Fundamental Studies and Relevance to Mental Illness. Front Neural Circuits 2018; 12:106. [PMID: 30627087 PMCID: PMC6309708 DOI: 10.3389/fncir.2018.00106] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 11/05/2018] [Indexed: 12/31/2022] Open
Abstract
Neuropeptides are auxiliary messenger molecules that always co-exist in nerve cells with one or more small molecule (classic) neurotransmitters. Neuropeptides act both as transmitters and trophic factors, and play a role particularly when the nervous system is challenged, as by injury, pain or stress. Here neuropeptides and coexistence in mammals are reviewed, but with special focus on the 29/30 amino acid galanin and its three receptors GalR1, -R2 and -R3. In particular, galanin's role as a co-transmitter in both rodent and human noradrenergic locus coeruleus (LC) neurons is addressed. Extensive experimental animal data strongly suggest a role for the galanin system in depression-like behavior. The translational potential of these results was tested by studying the galanin system in postmortem human brains, first in normal brains, and then in a comparison of five regions of brains obtained from depressed people who committed suicide, and from matched controls. The distribution of galanin and the four galanin system transcripts in the normal human brain was determined, and selective and parallel changes in levels of transcripts and DNA methylation for galanin and its three receptors were assessed in depressed patients who committed suicide: upregulation of transcripts, e.g., for galanin and GalR3 in LC, paralleled by a decrease in DNA methylation, suggesting involvement of epigenetic mechanisms. It is hypothesized that, when exposed to severe stress, the noradrenergic LC neurons fire in bursts and release galanin from their soma/dendrites. Galanin then acts on somato-dendritic, inhibitory galanin autoreceptors, opening potassium channels and inhibiting firing. The purpose of these autoreceptors is to act as a 'brake' to prevent overexcitation, a brake that is also part of resilience to stress that protects against depression. Depression then arises when the inhibition is too strong and long lasting - a maladaption, allostatic load, leading to depletion of NA levels in the forebrain. It is suggested that disinhibition by a galanin antagonist may have antidepressant activity by restoring forebrain NA levels. A role of galanin in depression is also supported by a recent candidate gene study, showing that variants in genes for galanin and its three receptors confer increased risk of depression and anxiety in people who experienced childhood adversity or recent negative life events. In summary, galanin, a neuropeptide coexisting in LC neurons, may participate in the mechanism underlying resilience against a serious and common disorder, MDD. Existing and further results may lead to an increased understanding of how this illness develops, which in turn could provide a basis for its treatment.
Collapse
Affiliation(s)
- Tomas Hökfelt
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Swapnali Barde
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Zhi-Qing David Xu
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
- Department of Neurobiology, Beijing Key Laboratory of Neural Regeneration and Repair, Beijing Laboratory of Brain Disorders (Ministry of Science and Technology), Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Eugenia Kuteeva
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Joelle Rüegg
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
- The Center for Molecular Medicine, Stockholm, Sweden
- Swedish Toxicology Sciences Research Center, Swetox, Södertälje, Sweden
| | - Erwan Le Maitre
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Mårten Risling
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Jan Kehr
- Pronexus Analytical AB, Solna, Sweden
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Robert Ihnatko
- Department of Clinical Chemistry, Linköping University, Linköping, Sweden
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Elvar Theodorsson
- Department of Clinical Chemistry, Linköping University, Linköping, Sweden
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Miklos Palkovits
- Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, Hungary
| | - William Deakin
- Neuroscience and Psychiatry Unit, University of Manchester, Manchester, United Kingdom
| | - Gyorgy Bagdy
- Department of Pharmacodynamics, Semmelweis University, Budapest, Hungary
- MTA-SE Neuropsychopharmacology and Neurochemistry Research Group, Hungarian Academy of Sciences, Semmelweis University, Budapest, Hungary
- NAP 2-SE New Antidepressant Target Research Group, Hungarian Brain Research Program, Semmelweis University, Budapest, Hungary
| | - Gabriella Juhasz
- Neuroscience and Psychiatry Unit, University of Manchester, Manchester, United Kingdom
- Department of Pharmacodynamics, Semmelweis University, Budapest, Hungary
- SE-NAP2 Genetic Brain Imaging Migraine Research Group, Hungarian Brain Research Program, Semmelweis University, Budapest, Hungary
| | | | - Naguib Mechawar
- Douglas Hospital Research Centre, Verdun, QC, Canada
- Department of Psychiatry, McGill University, Montreal, QC, Canada
| | | | - Sven Ove Ögren
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| |
Collapse
|
5
|
Camacho MB, Anastasio TJ. Computational Model of Antidepressant Response Heterogeneity as Multi-pathway Neuroadaptation. Front Pharmacol 2018; 8:925. [PMID: 29375372 PMCID: PMC5770730 DOI: 10.3389/fphar.2017.00925] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 12/06/2017] [Indexed: 12/28/2022] Open
Abstract
Current hypotheses cannot fully explain the clinically observed heterogeneity in antidepressant response. The therapeutic latency of antidepressants suggests that therapeutic outcomes are achieved not by the acute effects of the drugs, but rather by the homeostatic changes that occur as the brain adapts to their chronic administration. We present a computational model that represents the known interactions between the monoaminergic neurotransmitter-producing brain regions and associated non-monoaminergic neurotransmitter systems, and use the model to explore the possible ways in which the brain can homeostatically adjust to chronic antidepressant administration. The model also represents the neuron-specific neurotransmitter receptors that are known to adjust their strengths (expressions or sensitivities) in response to chronic antidepressant administration, and neuroadaptation in the model occurs through sequential adjustments in these receptor strengths. The main result is that the model can reach similar levels of adaptation to chronic administration of the same antidepressant drug or combination along many different pathways, arriving correspondingly at many different receptor strength configurations, but not all of those adapted configurations are also associated with therapeutic elevations in monoamine levels. When expressed as the percentage of adapted configurations that are also associated with elevations in one or more of the monoamines, our modeling results largely agree with the percentage efficacy rates of antidepressants and antidepressant combinations observed in clinical trials. Our neuroadaptation model provides an explanation for the clinical reports of heterogeneous outcomes among patients chronically administered the same antidepressant drug regimen.
Collapse
Affiliation(s)
- Mariam B Camacho
- Computational Neurobiology Laboratory, Beckman Institute for Advanced Science and Technology, Neuroscience Program, Medical Scholars Program, University of Illinois College of Medicine at Urbana-Champaign, Urbana, IL, United States
| | - Thomas J Anastasio
- Computational Neurobiology Laboratory, Department of Molecular and Integrative Physiology, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| |
Collapse
|
6
|
Beart PM. Synaptic signalling and its interface with neuropathologies: snapshots from the past, present and future. J Neurochem 2016; 139 Suppl 2:76-90. [PMID: 27144305 DOI: 10.1111/jnc.13598] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 02/09/2016] [Accepted: 02/26/2016] [Indexed: 11/30/2022]
Abstract
This 'Past to Future' Review as part of the 60th anniversary year of the Journal of Neurochemistry focuses on synaptic transmission and associated signalling, and seeks to identify seminal progress in neurochemistry over the last 10 years which has advanced our understanding of neuronal communication in brain. The approach adopted analyses neurotransmitters on a case by case basis (i.e. amino acids, monoamines, acetylcholine, neuropeptides, ATP/purines and gasotransmitters) to highlight novel findings that have changed the way we view each type of transmitter, to explore commonalities and interactions, and to note how new insights have changed the way we view the biology of degenerative, psychiatric and behavioural conditions. Across all transmitter systems there was remarkable growth in the identification of targets likely to provide therapeutic benefit and which undoubtedly was driven by the elucidation of circuit function and new vistas of synaptic signalling. There has been an increasing trend to relate signalling to disease, notably for Alzheimer's and Parkinson's disease and related conditions, and which has occurred for each transmitter family. Forebrain circuitry and tonic excitatory control have been the centre of great attention yielding novel findings that will impact upon cognitive, emotional and addictive behaviours. Other impressive insights focus on gasotransmitters integrating activity as volume transmitters. Exciting developments in how serotonin, cholinergic, l-glutamate, galanin and adenosine receptors and their associated signalling can be beneficially targeted should underpin the development of new therapies. Clearly integrated, multifaceted neurochemistry has changed the way we view synaptic signalling and its relevance to pathobiology. Highlighted are important advances in synaptic signalling over the last decade in the Journal of Neurochemistry. Across all transmitter systems elucidation of circuit function, and notably molecular insights, have underpinned remarkable growth in the identification of targets likely to provide therapeutic benefit in neuropathologies. Another commonality was wide interest in forebrain circuitry and its tonic excitatory control. Increasingly observations relate to signalling in disease and behavioural conditions. This article is part of the 60th Anniversary special issue.
Collapse
Affiliation(s)
- Philip M Beart
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia.
| |
Collapse
|
7
|
Weinshenker D, Holmes PV. Regulation of neurological and neuropsychiatric phenotypes by locus coeruleus-derived galanin. Brain Res 2015; 1641:320-37. [PMID: 26607256 DOI: 10.1016/j.brainres.2015.11.025] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 10/27/2015] [Accepted: 11/12/2015] [Indexed: 12/28/2022]
Abstract
Decades of research confirm that noradrenergic locus coeruleus (LC) neurons are essential for arousal, attention, motivation, and stress responses. While most studies on LC transmission focused unsurprisingly on norepinephrine (NE), adrenergic signaling cannot account for all the consequences of LC activation. Galanin coexists with NE in the vast majority of LC neurons, yet the precise function of this neuropeptide has proved to be surprisingly elusive given our solid understanding of the LC system. To elucidate the contribution of galanin to LC physiology, here we briefly summarize the nature of stimuli that drive LC activity from a neuroanatomical perspective. We go on to describe the LC pathways in which galanin most likely exerts its effects on behavior, with a focus on addiction, depression, epilepsy, stress, and Alzheimer׳s disease. We propose a model in which LC-derived galanin has two distinct functions: as a neuromodulator, primarily acting via the galanin 1 receptor (GAL1), and as a trophic factor, primarily acting via galanin receptor 2 (GAL2). Finally, we discuss how the recent advances in neuropeptide detection, optogenetics and chemical genetics, and galanin receptor pharmacology can be harnessed to identify the roles of LC-derived galanin definitively. This article is part of a Special Issue entitled SI: Noradrenergic System.
Collapse
Affiliation(s)
- David Weinshenker
- Department of Human Genetics, Emory University School of Medicine, 615 Michael St., Whitehead 301, Atlanta, GA 30322, USA.
| | - Philip V Holmes
- Neuroscience Program, Biomedical and Health Sciences Institute and Psychology Department, University of Georgia, Athens, GA 30602, USA.
| |
Collapse
|
8
|
Kerr N, Holmes FE, Hobson SA, Vanderplank P, Leard A, Balthasar N, Wynick D. The generation of knock-in mice expressing fluorescently tagged galanin receptors 1 and 2. Mol Cell Neurosci 2015; 68:258-71. [PMID: 26292267 PMCID: PMC4604734 DOI: 10.1016/j.mcn.2015.08.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 08/06/2015] [Accepted: 08/10/2015] [Indexed: 12/12/2022] Open
Abstract
The neuropeptide galanin has diverse roles in the central and peripheral nervous systems, by activating the G protein-coupled receptors Gal1, Gal2 and the less studied Gal3 (GalR1-3 gene products). There is a wealth of data on expression of Gal1-3 at the mRNA level, but not at the protein level due to the lack of specificity of currently available antibodies. Here we report the generation of knock-in mice expressing Gal1 or Gal2 receptor fluorescently tagged at the C-terminus with, respectively, mCherry or hrGFP (humanized Renilla green fluorescent protein). In dorsal root ganglia (DRG) neurons expressing the highest levels of Gal1-mCherry, localization to the somatic cell membrane was detected by live-cell fluorescence and immunohistochemistry, and that fluorescence decreased upon addition of galanin. In spinal cord, abundant Gal1-mCherry immunoreactive processes were detected in the superficial layers of the dorsal horn, and highly expressing intrinsic neurons of the lamina III/IV border showed both somatic cell membrane localization and outward transport of receptor from the cell body, detected as puncta within cell processes. In brain, high levels of Gal1-mCherry immunofluorescence were detected within thalamus, hypothalamus and amygdala, with a high density of nerve endings in the external zone of the median eminence, and regions with lesser immunoreactivity included the dorsal raphe nucleus. Gal2-hrGFP mRNA was detected in DRG, but live-cell fluorescence was at the limits of detection, drawing attention to both the much lower mRNA expression than to Gal1 in mice and the previously unrecognized potential for translational control by upstream open reading frames (uORFs).
Collapse
MESH Headings
- Animals
- Brain/metabolism
- Cells, Cultured
- Ganglia, Spinal/cytology
- Green Fluorescent Proteins/genetics
- Green Fluorescent Proteins/metabolism
- Luminescent Proteins/genetics
- Luminescent Proteins/metabolism
- Mice
- Mice, Transgenic
- Microscopy, Confocal
- Neurons/physiology
- RNA, Messenger/metabolism
- Receptor, Galanin, Type 1/genetics
- Receptor, Galanin, Type 1/metabolism
- Receptor, Galanin, Type 2/genetics
- Receptor, Galanin, Type 2/metabolism
- Spinal Cord/metabolism
- Red Fluorescent Protein
Collapse
Affiliation(s)
- Niall Kerr
- Schools of Physiology and Pharmacology and Clinical Sciences, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Fiona E Holmes
- Schools of Physiology and Pharmacology and Clinical Sciences, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Sally-Ann Hobson
- Schools of Physiology and Pharmacology and Clinical Sciences, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Penny Vanderplank
- Schools of Physiology and Pharmacology and Clinical Sciences, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Alan Leard
- Wolfson Bioimaging Facility, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Nina Balthasar
- Schools of Physiology and Pharmacology and Clinical Sciences, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - David Wynick
- Schools of Physiology and Pharmacology and Clinical Sciences, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK.
| |
Collapse
|
9
|
Eaton SL, Hurtado ML, Oldknow KJ, Graham LC, Marchant TW, Gillingwater TH, Farquharson C, Wishart TM. A guide to modern quantitative fluorescent western blotting with troubleshooting strategies. JOURNAL OF VISUALIZED EXPERIMENTS : JOVE 2014:e52099. [PMID: 25490604 PMCID: PMC4354265 DOI: 10.3791/52099] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The late 1970s saw the first publicly reported use of the western blot, a technique for assessing the presence and relative abundance of specific proteins within complex biological samples. Since then, western blotting methodology has become a common component of the molecular biologists experimental repertoire. A cursory search of PubMed using the term "western blot" suggests that in excess of two hundred and twenty thousand published manuscripts have made use of this technique by the year 2014. Importantly, the last ten years have seen technical imaging advances coupled with the development of sensitive fluorescent labels which have improved sensitivity and yielded even greater ranges of linear detection. The result is a now truly Quantifiable Fluorescence based Western Blot (QFWB) that allows biologists to carry out comparative expression analysis with greater sensitivity and accuracy than ever before. Many "optimized" western blotting methodologies exist and are utilized in different laboratories. These often prove difficult to implement due to the requirement of subtle but undocumented procedural amendments. This protocol provides a comprehensive description of an established and robust QFWB method, complete with troubleshooting strategies.
Collapse
Affiliation(s)
- Samantha L. Eaton
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh
| | - Maica Llavero Hurtado
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh
| | - Karla J. Oldknow
- Division of Developmental Biology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh
| | - Laura C. Graham
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh
| | - Thomas W. Marchant
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh
| | - Thomas H. Gillingwater
- Centre for Integrative Physiology, University of Edinburgh,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh
| | - Colin Farquharson
- Division of Developmental Biology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh
| | - Thomas M. Wishart
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh
| |
Collapse
|
10
|
The role of galanin system in modulating depression, anxiety, and addiction-like behaviors after chronic restraint stress. Neuroscience 2013; 246:82-93. [DOI: 10.1016/j.neuroscience.2013.04.046] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Revised: 04/19/2013] [Accepted: 04/22/2013] [Indexed: 11/21/2022]
|
11
|
Distinct features of neurotransmitter systems in the human brain with focus on the galanin system in locus coeruleus and dorsal raphe. Proc Natl Acad Sci U S A 2013; 110:E536-45. [PMID: 23341594 DOI: 10.1073/pnas.1221378110] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Using riboprobe in situ hybridization, we studied the localization of the transcripts for the neuropeptide galanin and its receptors (GalR1-R3), tryptophan hydroxylase 2, tyrosine hydroxylase, and nitric oxide synthase as well as the three vesicular glutamate transporters (VGLUT 1-3) in the locus coeruleus (LC) and the dorsal raphe nucleus (DRN) regions of postmortem human brains. Quantitative real-time PCR (qPCR) was used also. Galanin and GalR3 mRNA were found in many noradrenergic LC neurons, and GalR3 overlapped with serotonin neurons in the DRN. The qPCR analysis at the LC level ranked the transcripts in the following order in the LC: galanin >> GalR3 >> GalR1 > GalR2; in the DRN the ranking was galanin >> GalR3 >> GalR1 = GalR2. In forebrain regions the ranking was GalR1 > galanin > GalR2. VGLUT1 and -2 were strongly expressed in the pontine nuclei but could not be detected in LC or serotonin neurons. VGLUT2 transcripts were found in very small, nonpigmented cells in the LC and in the lateral and dorsal aspects of the periaqueductal central gray. Nitric oxide synthase was not detected in serotonin neurons. These findings show distinct differences between the human brain and rodents, especially rat, in the distribution of the galanin system and some other transmitter systems. For example, GalR3 seems to be the important galanin receptor in both the human LC and DRN versus GalR1 and -2 in the rodent brain. Such knowledge may be important when considering therapeutic principles and drug development.
Collapse
|
12
|
Humes DJ, Simpson J, Smith J, Sutton P, Zaitoun A, Bush D, Bennett A, Scholefield JH, Spiller RC. Visceral hypersensitivity in symptomatic diverticular disease and the role of neuropeptides and low grade inflammation. Neurogastroenterol Motil 2012; 24:318-e163. [PMID: 22276853 DOI: 10.1111/j.1365-2982.2011.01863.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND Recurrent abdominal pain is reported by a third of patients with diverticulosis, particularly those with previous episodes of acute diverticulitis. The current understanding of the etiology of this pain is poor. Our aim was to assess visceral sensitivity in patients with diverticular disease and its association with markers of previous inflammation and neuropeptides. METHODS Patients with asymptomatic and symptomatic diverticular disease underwent a flexible sigmoidoscopy and biopsy followed 5-10 days later by visceral sensitivity testing with barostat-mediated rectal distension. Inflammation was assessed by staining of serotonin (5HT) and CD3 positive cells. mRNA levels of tumor necrosis factor alpha (TNF α) and interleukin-6 (IL-6) were quantitated using RT-PCR. Neuropeptide expression was assessed from percentage area staining with substance P (SP) and mRNA levels of the neurokinin 1 & 2 receptors (NK1 & NK2), and galanin 1 receptor (GALR1). KEY RESULTS Thirteen asymptomatic and 12 symptomatic patients were recruited. The symptomatic patients had a lower first reported threshold to pain (28.4 mmHg i.q.r 25.0-36.0) than the asymptomatic patients (47 mmHg i.q.r 36.0-52.5, P < 0.001). Symptomatic patients had a higher median overall pain rating for the stimuli than the asymptomatic patients (P < 0.02). Symptomatic patients had greater median relative expression of NK1 and TNF alpha mRNA compared with asymptomatic patients. There was a significant correlation between barostat VAS pain scores and NK 1 expression (Figure 4, r(2) 0.54, P < 0.02). CONCLUSIONS & INFERENCES Patients with symptomatic diverticular disease exhibit visceral hypersensitivity, and this may be mediated by ongoing low grade inflammation and upregulation of tachykinins.
Collapse
Affiliation(s)
- D J Humes
- Nottingham Digestive Disease Centre and Biomedical Research Unit, Nottingham University Hospital NHS Trust, Nottingham, UK.
| | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Holmes FE, Armenaki A, Iismaa TP, Einstein EB, Shine J, Picciotto MR, Wynick D, Zachariou V. Galanin negatively modulates opiate withdrawal via galanin receptor 1. Psychopharmacology (Berl) 2012; 220:619-25. [PMID: 21969124 PMCID: PMC3324978 DOI: 10.1007/s00213-011-2515-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Accepted: 09/15/2011] [Indexed: 12/15/2022]
Abstract
RATIONALE The neuropeptide galanin has been shown to modulate opiate dependence and withdrawal. These effects could be mediated via activation of one or more of the three distinct G protein-coupled receptors, namely galanin receptors 1 (GalR1), 2 (GalR2), and 3 (GalR3). OBJECTIVES In this study, we used several transgenic mouse lines to further define the mechanisms underlying the role played by galanin and its receptors in the modulation of morphine dependence. First, transgenic mice expressing β-galactosidase under the control of the galanin promoter were used to assess the regulation of galanin expression in response to chronic morphine administration and withdrawal. Next, the behavioral responses to chronic morphine administration and withdrawal were tested in mice that over-express galanin, lack the GalR1 gene, or lack the GalR2 gene. METHODS Transgenic and matched wild-type mice were given increasing doses of morphine followed by precipitation of withdrawal by naloxone and behavioral responses to withdrawal were assessed. RESULTS Both morphine administration and withdrawal increased galanin gene transcription in the locus coeruleus (LC). Increasing galanin levels in the brain reduced signs of opiate withdrawal. Mice lacking GalR1 undergo more severe opiate withdrawal, whereas mice lacking GalR2 show no significant difference in withdrawal signs, compare with matched wild-type controls. CONCLUSIONS Opiate administration and withdrawal increase galanin expression in the LC. Galanin opposes the actions of morphine which leads to opiate dependence and withdrawal, an effect that is mediated via GalR1.
Collapse
MESH Headings
- Animals
- Behavior, Animal/drug effects
- Brain/drug effects
- Brain/metabolism
- Galanin/metabolism
- Gene Expression Regulation
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Morphine/administration & dosage
- Morphine/adverse effects
- Naloxone/pharmacology
- Narcotic Antagonists/pharmacology
- Opioid-Related Disorders/physiopathology
- Receptor, Galanin, Type 1/genetics
- Receptor, Galanin, Type 1/metabolism
- Receptor, Galanin, Type 2/genetics
- Receptor, Galanin, Type 2/metabolism
- Receptor, Galanin, Type 3/genetics
- Receptor, Galanin, Type 3/metabolism
- Substance Withdrawal Syndrome/physiopathology
Collapse
Affiliation(s)
- Fiona E Holmes
- Schools of Physiology and Pharmacology and Clinical Sciences, University of Bristol, Bristol, UK
| | | | | | | | | | | | | | | |
Collapse
|
14
|
Webling KEB, Runesson J, Bartfai T, Langel Ü. Galanin receptors and ligands. Front Endocrinol (Lausanne) 2012; 3:146. [PMID: 23233848 PMCID: PMC3516677 DOI: 10.3389/fendo.2012.00146] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Accepted: 11/08/2012] [Indexed: 12/13/2022] Open
Abstract
The neuropeptide galanin was first discovered 30 years ago. Today, the galanin family consists of galanin, galanin-like peptide (GALP), galanin-message associated peptide (GMAP), and alarin and this family has been shown to be involved in a wide variety of biological and pathological functions. The effect is mediated through three GPCR subtypes, GalR1-3. The limited number of specific ligands to the galanin receptor subtypes has hindered the understanding of the individual effects of each receptor subtype. This review aims to summarize the current data of the importance of the galanin receptor subtypes and receptor subtype specific agonists and antagonists and their involvement in different biological and pathological functions.
Collapse
Affiliation(s)
- Kristin E. B. Webling
- Department of Neurochemistry, Arrhenius Laboratories for Natural Science, Stockholm UniversityStockholm, Sweden
- *Correspondence: Kristin E. B. Webling, Department of Neurochemistry, Arrhenius Laboratories for Natural Science, Stockholm University, Svante Arrheniusv. 21A, 10691 Stockholm, Sweden. e-mail:
| | - Johan Runesson
- Department of Neurochemistry, Arrhenius Laboratories for Natural Science, Stockholm UniversityStockholm, Sweden
| | - Tamas Bartfai
- Molecular and Integrative Neurosciences Department, The Scripps Research InstituteLa Jolla, CA, USA
| | - Ülo Langel
- Department of Neurochemistry, Arrhenius Laboratories for Natural Science, Stockholm UniversityStockholm, Sweden
- Institute of Technology, University of TartuTartu, Estonia
| |
Collapse
|
15
|
Barson JR, Chang GQ, Poon K, Morganstern I, Leibowitz SF. Galanin and the orexin 2 receptor as possible regulators of enkephalin in the paraventricular nucleus of the hypothalamus: relation to dietary fat. Neuroscience 2011; 193:10-20. [PMID: 21821102 DOI: 10.1016/j.neuroscience.2011.07.057] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Revised: 06/29/2011] [Accepted: 07/23/2011] [Indexed: 10/17/2022]
Abstract
Recent studies show that the non-opioid peptides, galanin (GAL) and orexin (OX), are similar to the opioid enkephalin (ENK) in being stimulated by dietary fat and also in enhancing the consumption of a high-fat diet (HFD). This suggests that, when an HFD is provided, these non-opioids may stimulate the opioid system to promote excess consumption of this diet. Using single- and double-labeling immunohistochemistry, the present study sought to identify possible neuroanatomical substrates for this close relationship. Focusing on the hypothalamic paraventricular nucleus (PVN), and particularly its anterior (aPVN), middle (mPVN) and posterior (pPVN) parts, the experiments examined whether GAL itself or the receptors for GAL and OX are stimulated by an HFD in the same areas and possibly the same neurons as ENK. Compared to animals fed a standard chow diet, rats consuming an HFD exhibited an increased density of medial parvocellular neurons immunoreactive (IR) for GAL in the mPVN and aPVN and for ENK in the mPVN and pPVN, distinguishing the mPVN as an area where both peptides were affected. While showing little evidence for GAL and ENK colocalization with a chow diet, double-labeling studies in HFD-fed rats revealed significant colocalization specifically in medial parvocellular neurons of the mPVN. Immediately posterior to this site, further analyses revealed a similar relationship between the OX 2 receptor (OX(2)R) and ENK in HFD-treated animals. While increasing the density of neurons immunoreactive for OX(2)R as well as for the GAL 1 receptor but not OX 1 receptor, HFD consumption increased the colocalization only of OX(2)R and ENK, specifically in the medial parvocellular neurons of the pPVN. These changes in HFD-fed rats, showing GAL and OX(2)R to colocalize with ENK exclusively in neurons of the medial parvocellular mPVN and pPVN, respectively, suggest possible neural substrates through which the non-opioid peptides may functionally interact with ENK when exposed to an HFD.
Collapse
Affiliation(s)
- J R Barson
- Laboratory of Behavioral Neurobiology, 1230 York Avenue, The Rockefeller University, New York, NY 10065, USA
| | | | | | | | | |
Collapse
|
16
|
Readnower RD, Chavko M, Adeeb S, Conroy MD, Pauly JR, McCarron RM, Sullivan PG. Increase in blood-brain barrier permeability, oxidative stress, and activated microglia in a rat model of blast-induced traumatic brain injury. J Neurosci Res 2010; 88:3530-9. [PMID: 20882564 DOI: 10.1002/jnr.22510] [Citation(s) in RCA: 210] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2010] [Revised: 07/22/2010] [Accepted: 08/06/2010] [Indexed: 11/06/2022]
Abstract
Traumatic brain injury (TBI) as a consequence of exposure to blast is increasingly prevalent in military populations, with the underlying pathophysiological mechanisms mostly unknown. In the present study, we utilized an air-driven shock tube to investigate the effects of blast exposure (120 kPa) on rat brains. Immediately following exposure to blast, neurological function was reduced. BBB permeability was measured using IgG antibody and evaluating its immunoreactivity in the brain. At 3 and 24 hr postexposure, there was a transient significant increase in IgG staining in the cortex. At 3 days postexposure, IgG immunoreactivity returned to control levels. Quantitative immunostaining was employed to determine the temporal course of brain oxidative stress following exposure to blast. Levels of 4-hydroxynonenal (4-HNE) and 3-nitrotyrosine (3-NT) were significantly increased at 3 hr postexposure and returned to control levels at 24 hr postexposure. The response of microglia to blast exposure was determined by autoradiographic localization of (3) H-PK11195 binding. At 5 days postexposure, increased binding was observed in the contralateral and ipsilateral dentate gyrus. These regions also displayed increased binding at 10 days postexposure; in addition to these regions there was increased binding in the contralateral ventral hippocampus and substantia nigra at this time point. By using antibodies against CD11b/c, microglia morphology characteristic of activated microglia was observed in the hippocampus and substantia nigra of animals exposed to blast. These results indicate that BBB breakdown, oxidative stress, and microglia activation likely play a role in the neuropathology associated with TBI as a result of blast exposure.
Collapse
Affiliation(s)
- Ryan D Readnower
- Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536, USA
| | | | | | | | | | | | | |
Collapse
|
17
|
Abstract
There has been increasing interest in the ability of neuropeptides involved in feeding to modulate circuits important for responses to drugs of abuse. A number of peptides with effects on hypothalamic function also modulate the mesolimbic dopamine system (ventral tegmental area and nucleus accumbens). Similarly, common stress-related pathways can modulate food intake, drug reward and symptoms of drug withdrawal. Galanin promotes food intake and the analgesic properties of opiates, thus it initially seemed possible that galanin might potentiate opiate reinforcement. Instead, galanin agonists decrease opiate reward, measured by conditioned place preference, and opiate withdrawal signs, whereas opiate reward and withdrawal are increased in knockout mice lacking galanin. This is consistent with studies showing that galanin decreases activity-evoked dopamine release in striatal slices and decreases the firing rate of noradrenergic neurons in locus coeruleus, areas involved in drug reward and withdrawal, respectively. These data suggest that polymorphisms in genes encoding galanin or galanin receptors might be associated with susceptibility to opiate abuse. Further, galanin receptors might be potential targets for development of novel treatments for addiction.
Collapse
Affiliation(s)
- Marina R Picciotto
- Department of Psychiatry, Yale University School of Medicine, 34 Park Street, 3rd Floor Research, New Haven, CT 06508, USA.
| |
Collapse
|
18
|
Picciotto MR, Brabant C, Einstein EB, Kamens HM, Neugebauer NM. Effects of galanin on monoaminergic systems and HPA axis: Potential mechanisms underlying the effects of galanin on addiction- and stress-related behaviors. Brain Res 2009; 1314:206-18. [PMID: 19699187 DOI: 10.1016/j.brainres.2009.08.033] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Revised: 08/06/2009] [Accepted: 08/09/2009] [Indexed: 12/20/2022]
Abstract
Like a number of neuropeptides, galanin can alter neural activity in brain areas that are important for both stress-related behaviors and responses to drugs of abuse. Accordingly, drugs that target galanin receptors can alter behavioral responses to drugs of abuse and can modulate stress-related behaviors. Stress and drug-related behaviors are interrelated: stress can promote drug-seeking, and drug exposure and withdrawal can increase activity in brain circuits involved in the stress response. We review here what is known about the ability of galanin and galanin receptors to alter neuronal activity, and we discuss potential mechanisms that may underlie the effects of galanin on behaviors involved in responses to stress and addictive drugs. Understanding the mechanisms underlying galanin's effects on neuronal function in brain regions related to stress and addiction may be useful in developing novel therapeutics for the treatment of stress- and addiction-related disorders.
Collapse
Affiliation(s)
- Marina R Picciotto
- Division of Molecular Psychiatry, Abraham Ribicoff Research Facilities, Connecticut Mental Health Center, Yale University School of Medicine, New Haven, CT, USA.
| | | | | | | | | |
Collapse
|
19
|
Narasimhaiah R, Kamens HM, Picciotto MR. Effects of galanin on cocaine-mediated conditioned place preference and ERK signaling in mice. Psychopharmacology (Berl) 2009; 204:95-102. [PMID: 19099295 PMCID: PMC2872184 DOI: 10.1007/s00213-008-1438-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2007] [Accepted: 12/06/2008] [Indexed: 12/15/2022]
Abstract
RATIONALE The neuropeptide galanin and its receptors are expressed in brain regions implicated in the rewarding effects of natural stimuli and drugs of abuse. Galanin has been shown to attenuate neurochemical, physiological, and behavioral signs of opiate and amphetamine reinforcement. OBJECTIVE In the current study, we present evidence that galanin modulates neurochemical and behavioral correlates of cocaine response. METHODS Mice lacking the neuropeptide galanin (Gal -/-) and wild-type (Gal +/+) controls were used to analyze the effects of galanin in an unbiased conditioned place preference paradigm. We then examined cocaine-induced activation of extracellular signal-regulated kinase (ERK) activity as a marker of intracellular signaling in the mesolimbic dopaminergic pathway induced by acute cocaine administration RESULTS Gal -/- mice showed significantly greater conditioned place preference at a threshold dose of cocaine (3 mg/kg) than Gal +/+ mice, and this was reversed by administration of the galanin receptor agonist galnon. Consistent with the results of behavioral experiments, there was a significant increase in ERK activation in the ventral tegmental area (VTA) and nucleus accumbens (NAc) of Gal -/- mice but not Gal +/+ mice following acute, systemic cocaine injection at the threshold dose. In the NAc, but not VTA, this effect was reversed by administration of galnon. CONCLUSIONS These data, coupled with previous studies on the effects of morphine and amphetamine, demonstrate that galanin normally attenuates drug reinforcement, potentially via modulation of the mesolimbic dopamine system.
Collapse
Affiliation(s)
| | | | - Marina R. Picciotto
- To whom correspondence should be addressed. Department of Psychiatry, Yale University School of Medicine, 34 Park Street - 3rd floor research, New Haven, CT 06508, Tel: (203) 737-2041; Fax: (203) 737-2043;
| |
Collapse
|
20
|
Kuteeva E, Wardi T, Lundström L, Sollenberg U, Langel U, Hökfelt T, Ogren SO. Differential role of galanin receptors in the regulation of depression-like behavior and monoamine/stress-related genes at the cell body level. Neuropsychopharmacology 2008; 33:2573-85. [PMID: 18172432 DOI: 10.1038/sj.npp.1301660] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The present study on rat examined the role of galanin receptor subtypes in regulation of depression-like behavior as well as potential molecular mechanisms involved in the locus coeruleus (LC) and dorsal raphe (DR). The effect of intracerebroventricular (i.c.v.) infusion of galanin or galanin receptor GalR1- and GalR2-selective ligands was studied in the forced swim test, followed by quantitative in situ hybridization studies. Naive control, non-treated (swim control), saline- and fluoxetine-treated rats were used as controls in the behavioral and in situ hybridization studies. Subchronic treatment with fluoxetine reduced immobility and climbing time. Intracerebroventricular infusion of galanin, the GalR1 agonist M617 or the GalR2 antagonist M871 increased, while the GalR2(R3) agonist AR-M1896 decreased, immobility time compared to the aCSF-treated animals. Galanin also decreased the time of climbing. Galanin mRNA levels were upregulated by the combination of injection+swim stress in the saline- and the fluoxetine-treated groups in the LC, but not in the DR. Also tyrosine hydroxylase levels in the LC were increased following injection+swim stress in the saline- and fluoxetine-treated rats. Tryptophan hydroxylase 2 and serotonin transporter mRNAs were not significantly affected by any treatment. 5-HT(1A) mRNA levels were downregulated following i.c.v. galanin, M617 or AR-M1896 infusion. These results indicate a differential role of galanin receptor subtypes in depression-like behavior in rodents: GalR1 subtype may mediate 'prodepressive' and GalR2 'antidepressant' effects of galanin. Galanin has a role in behavioral adaptation to stressful events involving changes of molecules important for noradrenaline and/or serotonin transmission.
Collapse
Affiliation(s)
- Eugenia Kuteeva
- Department of Neuroscience, Karolinska Institutet, Retzius vag 8, Stockholm S-171 77 [corrected] Sweden.
| | | | | | | | | | | | | |
Collapse
|
21
|
Belfer I, Hipp H, Bollettino A, McKnight C, Evans C, Virkkunen M, Albaugh B, Max MB, Goldman D, Enoch MA. Alcoholism is associated withGALR3but not two other galanin receptor genes. GENES BRAIN AND BEHAVIOR 2007; 6:473-81. [PMID: 17083333 DOI: 10.1111/j.1601-183x.2006.00275.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The neuropeptide galanin is widely expressed in the periphery and the central nervous system and mediates diverse physiological processes and behaviors including alcohol abuse, depression and anxiety. Four genes encoding galanin and its receptors have been identified (GAL, GALR1, GALR2 and GALR3). Recently we found that GAL haplotypes were associated with alcoholism, raising the possibility that genetic variation in GALR1, GALR2 and GALR3 might also alter alcoholism risk. Tag single nucleotide polymorphisms (SNPs) were identified by genotyping SNP panels in controls from five populations. For the association study with alcoholism, six GALR1, four GALR2 and four GALR3 SNPs were genotyped in a large cohort of Finnish alcoholics and non-alcoholics. GALR3 showed a significant association with alcoholism that was driven by one SNP (rs3,091,367). Moreover, the combination of the GALR3 rs3,091,367 risk allele and GAL risk haplotypes led to a modestly increased odds ratio (OR) for alcoholism (2.4) as compared with the effect of either GAL (1.9) or GALR3 alone (1.4). Likewise, the combination of the GALR3 and GAL risk diplotypes led to an increased OR for alcoholism (4.6) as compared with the effect of either GAL (2.0) or GALR3 alone (1.6). There was no effect of GALR1 or GALR2 on alcoholism risk. This evidence suggests that GALR3 mediates the alcoholism-related actions of galanin.
Collapse
Affiliation(s)
- I Belfer
- Pain and Neurosensory Mechanisms Branch, National Institute of Dental and Craniofacial Research, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, DHHS, Bethesda, MD 20892, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Hawes JJ, Tuskan RG, Reilly KM. Nf1 expression is dependent on strain background: implications for tumor suppressor haploinsufficiency studies. Neurogenetics 2007; 8:121-30. [PMID: 17216419 PMCID: PMC6687394 DOI: 10.1007/s10048-006-0078-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2006] [Accepted: 12/15/2006] [Indexed: 11/29/2022]
Abstract
Neurofibromatosis type 1 (NF1) is the most common cancer predisposition syndrome affecting the nervous system, with elevated risk for both astrocytoma and peripheral nerve sheath tumors. NF1 is caused by a germline mutation in the NF1 gene, with tumors showing loss of the wild type copy of NF1. In addition, NF1 heterozygosity in surrounding stroma is important for tumor formation, suggesting an additional role of haploinsufficiency for NF1. Studies in mouse models and NF1 families have implicated modifier genes unlinked to NF1 in the severity of the disease and in susceptibility to astrocytoma and peripheral nerve sheath tumors. To determine if differences in Nf1 expression may contribute to the strain-specific effects on tumor predisposition, we examined the levels of Nf1 gene expression in mouse strains with differences in tumor susceptibility using quantitative polymerase chain reaction. The data presented in this paper demonstrate that strain background has as much effect on Nf1 expression levels as mutation of one Nf1 allele, indicating that studies of haploinsufficiency must be carefully interpreted with respect to strain background. Because expression levels do not correlate entirely with the susceptibility or resistance to tumors observed in the strain, these data suggest that either variation in Nf1 levels is not responsible for the differences in astrocytoma and peripheral nerve sheath tumor susceptibility in Nf1-/+;Trp53-/+cis mice, or that certain mouse strains have evolved compensatory mechanisms for differences in Nf1 expression.
Collapse
Affiliation(s)
- Jessica J Hawes
- Mouse Cancer Genetics Program, National Cancer Institute-Frederick, West 7th Street at Fort Detrick, P.O. Box B, Building 560, Rm 31-20, Frederick, MD 21702, USA
| | | | | |
Collapse
|
23
|
Kuteeva E, Wardi T, Hökfelt T, Ogren SO. Galanin enhances and a galanin antagonist attenuates depression-like behaviour in the rat. Eur Neuropsychopharmacol 2007; 17:64-9. [PMID: 16624535 DOI: 10.1016/j.euroneuro.2006.03.003] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2005] [Revised: 01/31/2006] [Accepted: 03/07/2006] [Indexed: 11/28/2022]
Abstract
The effect of intracerebroventricular infusion of galanin and/or the galanin antagonist M35 was studied in the forced swim test. Animals were pre-exposed to water for 15 min 24 h prior to test. Immobility and climbing were assessed during the second, 5 min exposure to water. Rats receiving a single infusion of galanin (3 nmol) displayed a significant increase of immobility. This effect was blocked by co-administration of M35 (1 nmol). M35 alone (1 nmol) produced a significant decrease of immobility. The results further support the hypothesis that galanin may play a role in mood disorders, and that galanin antagonists may represent new candidates for antidepressant treatment.
Collapse
Affiliation(s)
- Eugenia Kuteeva
- Department of Neuroscience, Karolinska Institutet, Retzius väg. 8, S-171 77 Stockholm, Sweden
| | | | | | | |
Collapse
|
24
|
Hobson SA, Holmes FE, Kerr NCH, Pope RJP, Wynick D. Mice deficient for galanin receptor 2 have decreased neurite outgrowth from adult sensory neurons and impaired pain-like behaviour. J Neurochem 2006; 99:1000-10. [PMID: 17076662 PMCID: PMC2725756 DOI: 10.1111/j.1471-4159.2006.04143.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Expression of the neuropeptide galanin is markedly up-regulated within the adult dorsal root ganglia (DRG) following peripheral nerve injury. We have previously demonstrated that galanin knockout (Gal-KO) mice have a developmental loss of a subset of DRG neurons. Galanin also plays a trophic role in the adult animal, and the rate of peripheral nerve regeneration and neurite outgrowth is reduced in adult Gal-KO mice. Here we describe the characterization of mice with an absence of GalR2 gene transcription (GalR2-MUT) and demonstrate that they have a 15% decrease in the number of calcitonin gene-related peptide (CGRP) expressing neuronal profiles in the adult DRG, associated with marked deficits in neuropathic and inflammatory pain behaviours. Adult GalR2-MUT animals also have a one third reduction in neurite outgrowth from cultured DRG neurons that cannot be rescued by either galanin or a high-affinity GalR2/3 agonist. Galanin activates extracellular signal-regulated kinase (ERK) and Akt in adult wild-type (WT) mouse DRG. Intact adult DRG from GalR2-MUT animals have lower levels of pERK and higher levels of pAkt than are found in WT controls. These data suggest that a lack of GalR2 activation in Gal-KO and GalR2-MUT animals is responsible for the observed developmental deficits in the DRG, and the decrease in neurite outgrowth in the adult.
Collapse
MESH Headings
- Animals
- Behavior, Animal/physiology
- Blotting, Western
- Extracellular Signal-Regulated MAP Kinases/metabolism
- Genotype
- Immunohistochemistry
- Male
- Mice
- Mice, Knockout
- Neurites/physiology
- Neurons, Afferent/physiology
- Pain/genetics
- Pain/psychology
- Peripheral Nerve Injuries
- Phenotype
- Phosphorylation
- Proto-Oncogene Proteins c-akt/physiology
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- Receptor, Galanin, Type 2/genetics
- Receptor, Galanin, Type 2/physiology
- Reverse Transcriptase Polymerase Chain Reaction
- Signal Transduction/genetics
- Signal Transduction/physiology
- Transcription, Genetic
Collapse
Affiliation(s)
- Sally-Ann Hobson
- Departments of Pharmacology and Clinical Science at South Bristol, Bristol University, Bristol, UK
| | - Fiona E. Holmes
- Departments of Pharmacology and Clinical Science at South Bristol, Bristol University, Bristol, UK
| | - Niall C. H. Kerr
- Departments of Pharmacology and Clinical Science at South Bristol, Bristol University, Bristol, UK
| | - Robert J. P. Pope
- Departments of Pharmacology and Clinical Science at South Bristol, Bristol University, Bristol, UK
| | - David Wynick
- Departments of Pharmacology and Clinical Science at South Bristol, Bristol University, Bristol, UK
| |
Collapse
|
25
|
Hawes JJ, Narasimhaiah R, Picciotto MR. Galanin attenuates cyclic AMP regulatory element-binding protein (CREB) phosphorylation induced by chronic morphine and naloxone challenge in Cath.a cells and primary striatal cultures. J Neurochem 2006; 96:1160-8. [PMID: 16417577 DOI: 10.1111/j.1471-4159.2005.03613.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Repeated morphine administration leads to molecular alterations of the neural circuitry in the locus coeruleus and nucleus accumbens. These changes include increased activity of several components of the cAMP signaling pathway that are thought to be associated with psychological and somatic signs of opiate withdrawal. The neuropeptide galanin has been shown to attenuate cAMP signaling in multiple cell types. The current study demonstrates that acute galanin treatment blocks the consequences of increased cAMP signaling following chronic opiate administration and withdrawal in Cath.a cells and primary cultures of striatal neurons as measured by phosphorylation of the transcription factor cAMP regulatory element-binding protein (CREB). In addition, galanin-mediated attenuation of CREB phosphorylation is independent of galanin-induced extracellular signal-regulated kinase (ERK) 1/2 phosphorylation in Cath.a cells. These data suggest that galanin receptors may serve as an additional potential therapeutic target for the treatment of opiate withdrawal.
Collapse
Affiliation(s)
- Jessica J Hawes
- Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut 06508, USA
| | | | | |
Collapse
|