1
|
Alyamni N, Abot JL, Zestos AG. Voltammetric detection of Neuropeptide Y using a modified sawhorse waveform. Anal Bioanal Chem 2024; 416:4807-4818. [PMID: 38914733 PMCID: PMC11315718 DOI: 10.1007/s00216-024-05373-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 05/23/2024] [Accepted: 05/29/2024] [Indexed: 06/26/2024]
Abstract
The hormone Neuropeptide Y (NPY) plays critical roles in feeding, satiety, obesity, and weight control. However, its complex peptide structure has hindered the development of fast and biocompatible detection methods. Previous studies utilizing electrochemical techniques with carbon fiber microelectrodes (CFMEs) have targeted the oxidation of amino acid residues like tyrosine to measure peptides. Here, we employ the modified sawhorse waveform (MSW) to enable voltammetric identification of NPY through tyrosine oxidation. Use of MSW improves NPY detection sensitivity and selectivity by reducing interference from catecholamines like dopamine, serotonin, and others compared to the traditional triangle waveform. The technique utilizes a holding potential of -0.2 V and a switching potential of 1.2 V that effectively etches and renews the CFME surface to simultaneously detect NPY and other monoamines with a sensitivity of 5.8 ± 0.94 nA/µM (n = 5). Furthermore, we observed adsorption-controlled, subsecond NPY measurements with CFMEs and MSW. The effective identification of exogenously applied NPY in biological fluids demonstrates the feasibility of this methodology for in vivo and ex vivo studies. These results highlight the potential of MSW voltammetry to enable fast, biocompatible NPY quantification to further elucidate its physiological roles.
Collapse
Affiliation(s)
- Nadiah Alyamni
- Department of Biomedical Engineering, The Catholic University of America, Washington, D.C., 20064, USA
- Department of Chemistry, American University, Washington, D.C., 20016, USA
| | - Jandro L Abot
- Department of Mechanical Engineering, The Catholic University of America, Washington, D.C., 20064, USA
| | - Alexander G Zestos
- Department of Chemistry, American University, Washington, D.C., 20016, USA.
| |
Collapse
|
2
|
Bompolaki M, Vantrease JE, DeJoseph MR, Miranda Tapia AP, Colmers WF, Urban JH. Activation of NPY Receptors in the BLA Inhibits Projections to the Bed Nucleus of the Stria Terminalis and Buffers Stress-Induced Decreases in Social Interaction in Male Rats. J Neurosci 2024; 44:e0228242024. [PMID: 39025677 PMCID: PMC11340280 DOI: 10.1523/jneurosci.0228-24.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 06/25/2024] [Accepted: 07/11/2024] [Indexed: 07/20/2024] Open
Abstract
Neuropeptide Y (NPY) increases resilience and buffers behavioral stress responses in male rats in part through decreasing the excitability of principal output neurons in the basolateral amygdala (BLA). Intra-BLA administration of NPY acutely increases social interaction (SI) through activation of either Y1 or Y5 receptors, whereas repeated NPY (rpNPY) injections (once daily for 5 d) produce persistent increases in SI through Y5 receptor-mediated neuroplasticity in the BLA. In this series of studies, we characterized the neural circuits from the BLA that underlie these behavioral responses to NPY. Using neuronal tract tracing, NPY Y1 and Y5 receptor immunoreactivity was identified on subpopulations of BLA neurons projecting to the bed nucleus of the stria terminalis (BNST) and the central nucleus of the amygdala (CeA). Inhibition of BLA→BNST, but not BLA→CeA, neurons using projection-restricted, cre-driven designer receptors exclusively activated by designer drug-Gi expression increased SI and prevented stress-induced decreases in SI produced by a 30 min restraint stress. This behavioral profile was similar to that seen after both acute and rpNPY injections into the BLA. Intracellular recordings of BLA→BNST neurons demonstrated NPY-mediated inhibition via suppression of H currents, as seen previously. Repeated intra-BLA injections of NPY, which are associated with the induction of BLA neuroplasticity, decreased the activity of BLA→BNST neurons and decreased their dendritic complexity. These results demonstrate that NPY modulates the activity of BNST-projecting BLA neurons, suggesting that this pathway contributes to the stress-buffering actions of NPY and provides a novel substrate for the proresilient effects of NPY.
Collapse
Affiliation(s)
- Maria Bompolaki
- Center for Neurobiology of Stress Resilience and Psychiatric Disorders; Discipline of Physiology and Biophysics, The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois 60064
| | - Jaime E Vantrease
- Center for Neurobiology of Stress Resilience and Psychiatric Disorders; Discipline of Physiology and Biophysics, The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois 60064
| | - Mary R DeJoseph
- Center for Neurobiology of Stress Resilience and Psychiatric Disorders; Discipline of Physiology and Biophysics, The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois 60064
| | - Ana P Miranda Tapia
- Department of Pharmacology, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
| | - William F Colmers
- Department of Pharmacology, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
| | - Janice H Urban
- Center for Neurobiology of Stress Resilience and Psychiatric Disorders; Discipline of Physiology and Biophysics, The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois 60064
| |
Collapse
|
3
|
Silveira MA, Herrera YN, Beebe NL, Schofield BR, Roberts MT. Lineage-tracing reveals an expanded population of NPY neurons in the inferior colliculus. J Neurophysiol 2024; 132:573-588. [PMID: 38988288 PMCID: PMC11427056 DOI: 10.1152/jn.00131.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 06/27/2024] [Accepted: 06/29/2024] [Indexed: 07/12/2024] Open
Abstract
Growing evidence suggests that neuropeptide signaling shapes auditory computations. We previously showed that neuropeptide Y (NPY) is expressed in the inferior colliculus (IC) by a population of GABAergic stellate neurons and that NPY regulates the strength of local excitatory circuits in the IC. NPY neurons were initially characterized using the NPY-hrGFP mouse, in which humanized renilla green fluorescent protein (hrGFP) expression indicates NPY expression at the time of assay, i.e., an expression-tracking approach. However, studies in other brain regions have shown that NPY expression can vary based on several factors, suggesting that the NPY-hrGFP mouse might miss NPY neurons not expressing NPY on the experiment date. Here, we hypothesized that neurons with the ability to express NPY represent a larger population of IC GABAergic neurons than previously reported. To test this hypothesis, we used a lineage-tracing approach to irreversibly tag neurons that expressed NPY at any point prior to the experiment date. We then compared the physiological and anatomical features of neurons labeled with this lineage-tracing approach to our prior data set, revealing a larger population of NPY neurons than previously found. In addition, we used optogenetics to test the local connectivity of NPY neurons and found that NPY neurons provide inhibitory synaptic input to other neurons in the ipsilateral IC. Together, our data expand the definition of NPY neurons in the IC, suggest that NPY expression might be dynamically regulated in the IC, and provide functional evidence that NPY neurons form local inhibitory circuits in the IC.NEW & NOTEWORTHY Across brain regions, neuropeptide Y (NPY) expression is dynamic and influenced by extrinsic and intrinsic factors. We previously showed that NPY is expressed by a class of inhibitory neurons in the auditory midbrain. Here, we find that this neuron class also includes neurons that previously expressed NPY, suggesting that NPY expression is dynamically regulated in the auditory midbrain. We also provide functional evidence that NPY neurons contribute to local inhibitory circuits in the auditory midbrain.
Collapse
Affiliation(s)
- Marina A Silveira
- Department of Otolaryngology-Head and Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, Michigan, United States
- Department of Neuroscience, Development and Regenerative Biology, The University of Texas at San Antonio, San Antonio, Texas, United States
| | - Yoani N Herrera
- Department of Otolaryngology-Head and Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, Michigan, United States
| | - Nichole L Beebe
- Department of Anatomy and Neurobiology, University Hospitals Hearing Research Center at NEOMED, Northeast Ohio Medical University, Rootstown, Ohio, United States
| | - Brett R Schofield
- Department of Anatomy and Neurobiology, University Hospitals Hearing Research Center at NEOMED, Northeast Ohio Medical University, Rootstown, Ohio, United States
| | - Michael T Roberts
- Department of Otolaryngology-Head and Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, Michigan, United States
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, United States
| |
Collapse
|
4
|
Silveira MA, Herrera YN, Beebe NL, Schofield BR, Roberts MT. Lineage-tracing reveals an expanded population of NPY neurons in the inferior colliculus. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.27.587042. [PMID: 38585909 PMCID: PMC10996674 DOI: 10.1101/2024.03.27.587042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Growing evidence suggests that neuropeptide signaling shapes auditory computations. We previously showed that neuropeptide Y (NPY) is expressed in the inferior colliculus (IC) by a population of GABAergic stellate neurons and that NPY regulates the strength of local excitatory circuits in the IC. NPY neurons were initially characterized using the NPY-hrGFP reporter mouse, in which hrGFP expression indicates NPY expression at the time of assay, i.e., an expression-tracking approach. However, studies in other brain regions have shown that NPY expression can vary based on a range of factors, suggesting that the NPY-hrGFP mouse might miss NPY neurons not expressing NPY proximal to the experiment date. Here, we hypothesized that neurons with the ability to express NPY represent a larger population of IC GABAergic neurons than previously reported. To test this hypothesis, we used a lineage-tracing approach to irreversibly tag neurons that expressed NPY at any point prior to the experiment date. We then compared the physiological and anatomical features of neurons labeled with this lineage-tracing approach to our prior data set, revealing a larger population of NPY neurons than previously found. In addition, we used optogenetics to test the local connectivity of NPY neurons and found that NPY neurons routinely provide inhibitory synaptic input to other neurons in the ipsilateral IC. Together, our data expand the definition of NPY neurons in the IC, suggest that NPY expression might be dynamically regulated in the IC, and provide functional evidence that NPY neurons form local inhibitory circuits in the IC.
Collapse
Affiliation(s)
- Marina A. Silveira
- Kresge Hearing Research Institute, Department of Otolaryngology – Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan
- Department of Neuroscience, Development and Regenerative Biology, The University of Texas at San Antonio, San Antonio, Texas
| | - Yoani N. Herrera
- Kresge Hearing Research Institute, Department of Otolaryngology – Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan
| | - Nichole L. Beebe
- University Hospitals Hearing Research Center at NEOMED, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Brett R. Schofield
- University Hospitals Hearing Research Center at NEOMED, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Michael T. Roberts
- Kresge Hearing Research Institute, Department of Otolaryngology – Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
| |
Collapse
|
5
|
Kornhuber J, Zoicas I. Valence-dependent effects of neuropeptide Y on the expression of conditioned fear and anxiety-like behavior: Involvement of the bed nucleus of the stria terminalis. Neuropharmacology 2024; 246:109847. [PMID: 38218578 DOI: 10.1016/j.neuropharm.2024.109847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 01/03/2024] [Accepted: 01/10/2024] [Indexed: 01/15/2024]
Abstract
Neuropeptide Y (NPY) has anxiolytic-like effects and facilitates the extinction of cued and contextual fear in rodents. We have previously shown that intracerebroventricular administration of NPY reduces the expression of social fear via simultaneous activation of Y1 and Y2 receptors in a mouse model of social fear conditioning (SFC). In the present study, we investigated whether the anteroventral bed nucleus of the stria terminalis (BNSTav) mediates these effects of NPY, given the important role of BNSTav in regulating anxiety- and fear-related behaviors. We show that while NPY (0.1 nmol/0.2 μl/side) did not reduce the expression of SFC-induced social fear in male CD1 mice, it reduced the expression of both cued and contextual fear by acting on Y2 but not on Y1 receptors within the BNSTav. Prior administration of the Y2 receptor antagonist BIIE0246 (0.2 nmol/0.2 μl/side) but not of the Y1 receptor antagonist BIBO3304 trifluoroacetate (0.2 nmol/0.2 μl/side) blocked the effects of NPY on the expression of cued and contextual fear. Similarly, NPY exerted non-social anxiolytic-like effects in the elevated plus maze test but not social anxiolytic-like effects in the social approach avoidance test by acting on Y2 receptors and not on Y1 receptors within the BNSTav. These results suggest that administration of NPY within the BNSTav exerts robust Y2 receptor-mediated fear-reducing and anxiolytic-like effects specifically in non-social contexts and add a novel piece of evidence regarding the neural underpinnings underlying the effects of NPY on conditioned fear and anxiety-like behavior.
Collapse
Affiliation(s)
- Johannes Kornhuber
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Schwabachanlage 6, 91054, Erlangen, Germany
| | - Iulia Zoicas
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Schwabachanlage 6, 91054, Erlangen, Germany.
| |
Collapse
|
6
|
Robinson SL, Bendrath SC, Yates EM, Thiele TE. Basolateral amygdala neuropeptide Y system modulates binge ethanol consumption. Neuropsychopharmacology 2024; 49:690-698. [PMID: 37758802 PMCID: PMC10876546 DOI: 10.1038/s41386-023-01742-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 08/22/2023] [Accepted: 09/12/2023] [Indexed: 09/29/2023]
Abstract
Neuropeptide Y (NPY) signaling regulation of corticolimbic communication is known to modulate binge-like ethanol consumption in rodents. In this work we sought to assess the impact of intra-BLA NPY system modulation on binge-like ethanol intake and to assess the role of the NPY1R+ projection from the BLA to the mPFC in this behavior. We used "drinking-in-the-dark" (DID) procedures in C57BL6J mice to address these questions. First, the impact of intra-BLA administration of NPY on binge-like ethanol intake was assessed. Next, the impact of repeated cycles of DID intake on NPY1R expression in the BLA was assessed with use of immunohistochemistry (IHC). Finally, chemogenetic inhibition of BLA→mPFC NPY1R+ projections was assessed to determine if limbic communication with the mPFC was specifically involved in binge-like ethanol intake. Importantly, as both the BLA and NPY system are sexually dimorphic, both sexes were assessed in these studies. Intra-BLA NPY dose-dependently decreased binge-like ethanol intake in males only. Repeated DID reduced NPY1R expression in the BLA of both sexes. Silencing of BLA→mPFC NPY1R+ neurons significantly reduced binge-like ethanol intake in both sexes in a dose-dependent manner. We provide novel evidence that (1) intra-BLA NPY reduces binge-like ethanol intake in males; (2) binge-like ethanol intake reduces NPY1R levels in the BLA; and (3) chemogenetic inhibition of BLA→mPFC NPY1R+ neurons blunts binge-like drinking in male and female mice. These observations provide the first direct evidence that NPY signaling in the BLA, and specifically BLA communication with the mPFC, modulates binge-like ethanol consumption.
Collapse
Affiliation(s)
- Stacey L Robinson
- Department of Psychology & Neuroscience, The University of North Carolina, Chapel Hill, NC, 27599-3270, USA
- Bowles Center for Alcohol Studies, The University of North Carolina, Chapel Hill, NC, 27599-7178, USA
| | - Sophie C Bendrath
- Department of Psychology & Neuroscience, The University of North Carolina, Chapel Hill, NC, 27599-3270, USA
- Bowles Center for Alcohol Studies, The University of North Carolina, Chapel Hill, NC, 27599-7178, USA
| | - Elizabeth M Yates
- Department of Psychology & Neuroscience, The University of North Carolina, Chapel Hill, NC, 27599-3270, USA
| | - Todd E Thiele
- Department of Psychology & Neuroscience, The University of North Carolina, Chapel Hill, NC, 27599-3270, USA.
- Bowles Center for Alcohol Studies, The University of North Carolina, Chapel Hill, NC, 27599-7178, USA.
| |
Collapse
|
7
|
Silveira MA, Drotos AC, Pirrone TM, Versalle TS, Bock A, Roberts MT. Neuropeptide Y Signaling Regulates Recurrent Excitation in the Auditory Midbrain. J Neurosci 2023; 43:7626-7641. [PMID: 37704372 PMCID: PMC10634549 DOI: 10.1523/jneurosci.0900-23.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 09/05/2023] [Accepted: 09/06/2023] [Indexed: 09/15/2023] Open
Abstract
Neuropeptides play key roles in shaping the organization and function of neuronal circuits. In the inferior colliculus (IC), which is in the auditory midbrain, Neuropeptide Y (NPY) is expressed by a class of GABAergic neurons that project locally and outside the IC. Most neurons in the IC have local axon collaterals; however, the organization and function of local circuits in the IC remain unknown. We previously found that excitatory neurons in the IC can express the NPY Y1 receptor (Y1R+) and application of the Y1R agonist, [Leu31, Pro34]-NPY (LP-NPY), decreases the excitability of Y1R+ neurons. As NPY signaling regulates recurrent excitation in other brain regions, we hypothesized that Y1R+ neurons form interconnected local circuits in the IC and that NPY decreases the strength of recurrent excitation in these circuits. To test this hypothesis, we used optogenetics to activate Y1R+ neurons in mice of both sexes while recording from other neurons in the ipsilateral IC. We found that nearly 80% of glutamatergic IC neurons express the Y1 receptor, providing extensive opportunities for NPY signaling to regulate local circuits. Additionally, Y1R+ neuron synapses exhibited modest short-term synaptic plasticity, suggesting that local excitatory circuits maintain their influence over computations during sustained stimuli. We further found that application of LP-NPY decreased recurrent excitation in the IC, suggesting that NPY signaling strongly regulates local circuit function in the auditory midbrain. Our findings show that Y1R+ excitatory neurons form interconnected local circuits in the IC, and their influence over local circuits is regulated by NPY signaling.SIGNIFICANCE STATEMENT Local networks play fundamental roles in shaping neuronal computations in the brain. The IC, localized in the auditory midbrain, plays an essential role in sound processing, but the organization of local circuits in the IC is largely unknown. Here, we show that IC neurons that express the Neuropeptide Y1 receptor (Y1R+ neurons) make up most of the excitatory neurons in the IC and form interconnected local circuits. Additionally, we found that NPY, which is a powerful neuromodulator known to shape neuronal activity in other brain regions, decreases the extensive recurrent excitation mediated by Y1R+ neurons in local IC circuits. Thus, our results suggest that local NPY signaling is a key regulator of auditory computations in the IC.
Collapse
Affiliation(s)
- Marina A Silveira
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan 48109
| | - Audrey C Drotos
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan 48109
| | - Trinity M Pirrone
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan 48109
- Macalester College, St. Paul, Minnesota 55105
| | - Trevor S Versalle
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan 48109
| | - Amanda Bock
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan 48109
| | - Michael T Roberts
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan 48109
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109
| |
Collapse
|
8
|
Sabban EL, Serova L, Nahvi RJ, Liu X. Potential benefits of intranasal neuropeptide Y include sustained extinction of fear memory. J Neuroendocrinol 2023; 35:e13279. [PMID: 37157881 DOI: 10.1111/jne.13279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 04/03/2023] [Accepted: 04/10/2023] [Indexed: 05/10/2023]
Abstract
Compelling evidence in animals and humans from a variety of approaches demonstrate that neuropeptide Y (NPY) in the brain can provide resilience to development of many stress-elicited symptoms. Preclinical experiments demonstrated that delivery of NPY by intranasal infusion to rats shortly after single exposure to traumatic stress in the single prolonged stress (SPS) rodent model of post-traumatic stress disorder (PTSD) can prevent development of many relevant behavioral alterations weeks later, including heightened anxiety and depressive-like behavior. Here, we examined responses to intranasal NPY in the absence of stress to evaluate the safety profile. Rats were administered intranasal NPY (150 μg/rat) or equal volume of vehicle (distilled water), and 7 days later they were tested on the elevated plus maze (EPM) and forced swim test (FST). There was no significant difference in the number of entries or duration in the open or closed arms, or in their anxiety index. Defecation on the EPM and immobility on the FST, measures of anxiety and depressive-like behavior respectively, were similar in both groups. To further characterize potential benefits of intranasal NPY, its effect on fear memory and extinction, important features of PTSD, were examined. Intranasal administration of NPY at the time of the traumatic stress had a profound effect on fear conditioning a week later. It prevented the SPS-triggered impairment in the retention of extinguished behavior, both contextual and cued. The findings support the translation of non-invasive intranasal NPY delivery to the brain for PTSD-behaviors including impairments in sustained extinction of fear memories.
Collapse
Affiliation(s)
- Esther L Sabban
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York, USA
| | - Lidia Serova
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York, USA
| | - Roxanna J Nahvi
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York, USA
| | - Xiaoping Liu
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York, USA
| |
Collapse
|
9
|
van de Poll Y, Cras Y, Ellender TJ. The neurophysiological basis of stress and anxiety - comparing neuronal diversity in the bed nucleus of the stria terminalis (BNST) across species. Front Cell Neurosci 2023; 17:1225758. [PMID: 37711509 PMCID: PMC10499361 DOI: 10.3389/fncel.2023.1225758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 08/03/2023] [Indexed: 09/16/2023] Open
Abstract
The bed nucleus of the stria terminalis (BNST), as part of the extended amygdala, has become a region of increasing interest regarding its role in numerous human stress-related psychiatric diseases, including post-traumatic stress disorder and generalized anxiety disorder amongst others. The BNST is a sexually dimorphic and highly complex structure as already evident by its anatomy consisting of 11 to 18 distinct sub-nuclei in rodents. Located in the ventral forebrain, the BNST is anatomically and functionally connected to many other limbic structures, including the amygdala, hypothalamic nuclei, basal ganglia, and hippocampus. Given this extensive connectivity, the BNST is thought to play a central and critical role in the integration of information on hedonic-valence, mood, arousal states, processing emotional information, and in general shape motivated and stress/anxiety-related behavior. Regarding its role in regulating stress and anxiety behavior the anterolateral group of the BNST (BNSTALG) has been extensively studied and contains a wide variety of neurons that differ in their electrophysiological properties, morphology, spatial organization, neuropeptidergic content and input and output synaptic organization which shape their activity and function. In addition to this great diversity, further species-specific differences are evident on multiple levels. For example, classic studies performed in adult rat brain identified three distinct neuron types (Type I-III) based on their electrophysiological properties and ion channel expression. Whilst similar neurons have been identified in other animal species, such as mice and non-human primates such as macaques, cross-species comparisons have revealed intriguing differences such as their comparative prevalence in the BNSTALG as well as their electrophysiological and morphological properties, amongst other differences. Given this tremendous complexity on multiple levels, the comprehensive elucidation of the BNSTALG circuitry and its role in regulating stress/anxiety-related behavior is a major challenge. In the present Review we bring together and highlight the key differences in BNSTALG structure, functional connectivity, the electrophysiological and morphological properties, and neuropeptidergic profiles of BNSTALG neurons between species with the aim to facilitate future studies of this important nucleus in relation to human disease.
Collapse
Affiliation(s)
- Yana van de Poll
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Yasmin Cras
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Tommas J. Ellender
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
10
|
Silveira MA, Drotos AC, Pirrone TM, Versalle TS, Bock A, Roberts MT. Neuropeptide Y signaling regulates recurrent excitation in the auditory midbrain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.16.540954. [PMID: 37292904 PMCID: PMC10245754 DOI: 10.1101/2023.05.16.540954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Neuropeptides play key roles in shaping the organization and function of neuronal circuits. In the inferior colliculus (IC), which is located in the auditory midbrain, Neuropeptide Y (NPY) is expressed by a large class of GABAergic neurons that project locally as well as outside the IC. The IC integrates information from numerous auditory nuclei making the IC an important hub for sound processing. Most neurons in the IC have local axon collaterals, however the organization and function of local circuits in the IC remains largely unknown. We previously found that neurons in the IC can express the NPY Y1 receptor (Y 1 R + ) and application of the Y 1 R agonist, [Leu 31 , Pro 34 ]-NPY (LP-NPY), decreases the excitability of Y 1 R + neurons. To investigate how Y 1 R + neurons and NPY signaling contribute to local IC networks, we used optogenetics to activate Y 1 R + neurons while recording from other neurons in the ipsilateral IC. Here, we show that 78.4% of glutamatergic neurons in the IC express the Y1 receptor, providing extensive opportunities for NPY signaling to regulate excitation in local IC circuits. Additionally, Y 1 R + neuron synapses exhibit modest short-term synaptic plasticity, suggesting that local excitatory circuits maintain their influence over computations during sustained stimuli. We further found that application of LP-NPY decreases recurrent excitation in the IC, suggesting that NPY signaling strongly regulates local circuit function in the auditory midbrain. Together, our data show that excitatory neurons are highly interconnected in the local IC and their influence over local circuits is tightly regulated by NPY signaling.
Collapse
Affiliation(s)
- Marina A. Silveira
- Kresge Hearing Research Institute, Department of Otolaryngology – Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan 48109
| | - Audrey C. Drotos
- Kresge Hearing Research Institute, Department of Otolaryngology – Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan 48109
| | - Trinity M. Pirrone
- Kresge Hearing Research Institute, Department of Otolaryngology – Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan 48109
- Macalester College, St. Paul, Minnesota 55105
| | - Trevor S. Versalle
- Kresge Hearing Research Institute, Department of Otolaryngology – Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan 48109
| | - Amanda Bock
- Kresge Hearing Research Institute, Department of Otolaryngology – Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan 48109
| | - Michael T. Roberts
- Kresge Hearing Research Institute, Department of Otolaryngology – Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan 48109
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, 48109
| |
Collapse
|
11
|
Exploring the role of neuropeptides in depression and anxiety. Prog Neuropsychopharmacol Biol Psychiatry 2022; 114:110478. [PMID: 34801611 DOI: 10.1016/j.pnpbp.2021.110478] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 11/13/2021] [Accepted: 11/13/2021] [Indexed: 12/24/2022]
Abstract
Depression is one of the most prevalent forms of mental disorders and is the most common cause of disability in the Western world. Besides, the harmful effects of stress-related mood disorders on the patients themselves, they challenge the health care system with enormous social and economic impacts. Due to the high proportion of patients not responding to existing drugs, finding new treatment strategies has become an important topic in neurobiology, and there is much evidence that neuropeptides are not only involved in the physiology of stress but may also be clinically important. Based on preclinical trial data, new neuropharmaceutical candidates may target neuropeptides and their receptors and are expected to be essential and valuable tools in the treatment of psychiatric disorders. In the current article, we have summarized data obtained from animal models of depressive disorder and transgenic mouse models. We also focus on previously published research data of clinical studies on corticotropin-releasing hormone (CRH), galanin (GAL), neuropeptide Y (NPY), neuropeptide S (NPS), Oxytocin (OXT), vasopressin (VP), cholecystokinin (CCK), and melanin-concentrating hormone (MCH) stress research fields.
Collapse
|
12
|
Restraint stress potentiates neuropeptide Y-mediated impairment on spatial memory in rats. Behav Brain Res 2022; 419:113705. [PMID: 34871704 DOI: 10.1016/j.bbr.2021.113705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 12/01/2021] [Accepted: 12/02/2021] [Indexed: 11/02/2022]
Abstract
Memory is the ability to store, retrieve and use information that requires a progressive time-dependent stabilization process known as consolidation to be established. The hippocampus is essential for processing all the information that forms memory, especially spatial memory. Neuropeptide Y (NPY) affects memory, so in this study we investigated the participation and recruitment of NPY receptors during spatial memory consolidation in rats. Using the water maze test, we show that NPY (1 pmol) injected into the dorsal hippocampus impaired memory consolidation and that previous restraint stress (30 min) potentiates NPY effects, i.e. further impaired memory consolidation. Using selective antagonists for NPY Y1 and Y2 receptors we demonstrate that both receptors play a key role on spatial memory consolidation. Our data suggest that NPY modulates aversive and adaptive memory formation by NPY receptors activation.
Collapse
|
13
|
The Role of Neuropeptide-Stimulated cAMP-EPACs Signalling in Cancer Cells. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27010311. [PMID: 35011543 PMCID: PMC8746471 DOI: 10.3390/molecules27010311] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 12/23/2021] [Accepted: 12/27/2021] [Indexed: 02/06/2023]
Abstract
Neuropeptides are autocrine and paracrine signalling factors and mainly bind to G protein-coupled receptors (GPCRs) to trigger intracellular secondary messenger release including adenosine 3′, 5′-cyclic monophosphate (cAMP), thus modulating cancer progress in different kind of tumours. As one of the downstream effectors of cAMP, exchange proteins directly activated by cAMP (EPACs) play dual roles in cancer proliferation and metastasis. More evidence about the relationship between neuropeptides and EPAC pathways have been proposed for their potential role in cancer development; hence, this review focuses on the role of neuropeptide/GPCR system modulation of cAMP/EPACs pathways in cancers. The correlated downstream pathways between neuropeptides and EPACs in cancer cell proliferation, migration, and metastasis is discussed to glimmer the direction of future research.
Collapse
|
14
|
Denny RR, Connelly KL, Ghilotti MG, Meissler JJ, Yu D, Eisenstein TK, Unterwald EM. Artificial Intelligence Identified Resilient and Vulnerable Female Rats After Traumatic Stress and Ethanol Exposure: Investigation of Neuropeptide Y Pathway Regulation. Front Neurosci 2021; 15:772946. [PMID: 34975380 PMCID: PMC8716605 DOI: 10.3389/fnins.2021.772946] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 11/18/2021] [Indexed: 11/13/2022] Open
Abstract
Post-traumatic stress disorder (PTSD) is initiated by traumatic-stress exposure and manifests into a collection of symptoms including increased anxiety, sleep disturbances, enhanced response to triggers, and increased sympathetic nervous system arousal. PTSD is highly co-occurring with alcohol use disorder. Only some individuals experiencing traumatic stress develop PTSD and a subset of individuals with PTSD develop co-occurring alcohol use disorder. To investigate the basis of these individual responses to traumatic stress, single prolonged stress (SPS) a rodent model of traumatic stress was applied to young adult female rats. Individual responses to SPS were characterized by measuring anxiety-like behaviors with open field and elevated plus maze tests. Rats were then allowed to drink ethanol under an intermittent two bottle choice procedure for 8 weeks, and ethanol consumption was measured. An artificial intelligence algorithm was built to predict resilient and vulnerable individuals based on data from anxiety testing and ethanol consumption. This model was implemented in a second cohort of rats that underwent SPS without ethanol drinking to identify resilient and vulnerable individuals for further study. Analysis of neuropeptide Y (NPY) levels and expression of its receptors Y1R and Y2R mRNA in the central nucleus of the amygdala (CeA), basolateral amygdala (BLA), and bed nucleus stria terminalis (BNST) were performed. Results demonstrate that resilient rats had higher expression of Y2R mRNA in the CeA compared with vulnerable and control rats and had higher levels of NPY protein in the BNST compared to controls. The results of the study show that an artificial intelligence algorithm can identify individual differences in response to traumatic stress which can be used to predict subsequent ethanol drinking, and the NPY pathway is differentially altered following traumatic stress exposure in resilient and vulnerable populations. Understanding neurochemical alterations following traumatic-stress exposure is critical in developing prevention strategies for the vulnerable phenotype and will help further development of novel therapeutic approaches for individuals suffering from PTSD and at risk for alcohol use disorder.
Collapse
Affiliation(s)
- Ray R. Denny
- Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States
| | - Krista L. Connelly
- Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States
| | - Marco G. Ghilotti
- Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States
| | - Joseph J. Meissler
- Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States
| | - Daohai Yu
- Center for Biostatistics and Epidemiology, Department of Biomedical Education and Data Science, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States
| | - Toby K. Eisenstein
- Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States,Department of Neural Sciences, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States
| | - Ellen M. Unterwald
- Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States,Department of Neural Sciences, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States,*Correspondence: Ellen M. Unterwald,
| |
Collapse
|
15
|
Neuropeptide Y Reduces Social Fear in Male Mice: Involvement of Y1 and Y2 Receptors in the Dorsolateral Septum and Central Amygdala. Int J Mol Sci 2021; 22:ijms221810142. [PMID: 34576305 PMCID: PMC8472534 DOI: 10.3390/ijms221810142] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 09/16/2021] [Accepted: 09/18/2021] [Indexed: 11/17/2022] Open
Abstract
Neuropeptide Y (NPY) has anxiolytic-like effects and facilitates the extinction of cued and contextual fear in rodents. We previously showed that intracerebroventricular administration of NPY reduces the expression of social fear in a mouse model of social fear conditioning (SFC) and localized these effects to the dorsolateral septum (DLS) and central amygdala (CeA). In the present study, we aimed to identify the receptor subtypes that mediate these local effects of NPY. We show that NPY (0.1 nmol/0.2 µL/side) reduced the expression of SFC-induced social fear in a brain region- and receptor-specific manner in male mice. In the DLS, NPY reduced the expression of social fear by acting on Y2 receptors but not on Y1 receptors. As such, prior administration of the Y2 receptor antagonist BIIE0246 (0.2 nmol/0.2 μL/side) but not the Y1 receptor antagonist BIBO3304 trifluoroacetate (0.2 nmol/0.2 μL/side) blocked the effects of NPY in the DLS. In the CeA, however, BIBO3304 trifluoroacetate but not BIIE0246 blocked the effects of NPY, suggesting that NPY reduced the expression of social fear by acting on Y1 receptors but not Y2 receptors within the CeA. This study suggests that at least two distinct receptor subtypes are differentially recruited in the DLS and CeA to mediate the effects of NPY on the expression of social fear.
Collapse
|
16
|
Comeras LB, Hörmer N, Mohan Bethuraj P, Tasan RO. NPY Released From GABA Neurons of the Dentate Gyrus Specially Reduces Contextual Fear Without Affecting Cued or Trace Fear. Front Synaptic Neurosci 2021; 13:635726. [PMID: 34122036 PMCID: PMC8187774 DOI: 10.3389/fnsyn.2021.635726] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 04/20/2021] [Indexed: 11/15/2022] Open
Abstract
Disproportionate, maladapted, and generalized fear are essential hallmarks of posttraumatic stress disorder (PTSD), which develops upon severe trauma in a subset of exposed individuals. Among the brain areas that are processing fear memories, the hippocampal formation exerts a central role linking emotional-affective with cognitive aspects. In the hippocampus, neuronal excitability is constrained by multiple GABAergic interneurons with highly specialized functions and an extensive repertoire of co-released neuromodulators. Neuropeptide Y (NPY) is one of these co-transmitters that significantly affects hippocampal signaling, with ample evidence supporting its fundamental role in emotional, cognitive, and metabolic circuitries. Here we investigated the role of NPY in relation to GABA, both released from the same interneurons of the dorsal dentate gyrus (DG), in different aspects of fear conditioning. We demonstrated that activation of dentate GABA neurons specifically during fear recall reduced cue-related as well as trace-related freezing behavior, whereas inhibition of the same neurons had no significant effects. Interestingly, concomitant overexpression of NPY in these neurons did not further modify fear recall, neither under baseline conditions nor upon chemogenetic stimulation. However, potentially increased co-release of NPY substantially reduced contextual fear, promoted extinction learning, and long-term suppression of fear in a foreground context–conditioning paradigm. Importantly, NPY in the dorsal DG was not only expressed in somatostatin neurons, but also in parvalbumin-positive basket cells and axoaxonic cells, indicating intense feedback and feedforward modulation of hippocampal signaling and precise curtailing of neuronal engrams. Thus, these findings suggest that co-release of NPY from specific interneuron populations of the dorsal DG modifies dedicated aspects of hippocampal processing by sharpening the activation of neural engrams and the consecutive fear response. Since inappropriate and generalized fear is the major impediment in the treatment of PTSD patients, the dentate NPY system may be a suitable access point to ameliorate PTSD symptoms and improve the inherent disease course.
Collapse
Affiliation(s)
- Lucas B Comeras
- Department of Pharmacology, Medical University Innsbruck, Innsbruck, Austria
| | - Noa Hörmer
- Department of Pharmacology, Medical University Innsbruck, Innsbruck, Austria
| | | | - Ramon O Tasan
- Department of Pharmacology, Medical University Innsbruck, Innsbruck, Austria
| |
Collapse
|
17
|
Kornhuber J, Zoicas I. Brain Region-Dependent Effects of Neuropeptide Y on Conditioned Social Fear and Anxiety-Like Behavior in Male Mice. Int J Mol Sci 2021; 22:ijms22073695. [PMID: 33918123 PMCID: PMC8037261 DOI: 10.3390/ijms22073695] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 03/29/2021] [Accepted: 03/30/2021] [Indexed: 11/16/2022] Open
Abstract
Neuropeptide Y (NPY) has anxiolytic-like effects and facilitates the extinction of cued and contextual fear in rodents. We have previously shown that the intracerebroventricular administration of NPY reduces the expression of social fear in a mouse model of social fear conditioning (SFC). In the present study, we aimed to identify the brain regions that mediate these effects of NPY. We show that NPY (0.1 nmol/0.2 µL/side) reduces the expression of SFC-induced social fear in a brain-region-dependent manner. In more detail, NPY reduced the expression of social fear when administered into the dorsolateral septum (DLS) and central amygdala (CeA), but not when administered into the dorsal hippocampus (DH), medial amygdala (MeA) and basolateral amygdala (BLA). We also investigated whether the reduced expression of social fear might partly be due to a reduced anxiety-like behavior, and showed that NPY exerted anxiolytic-like effects when administered into the DH, DLS, CeA and BLA, but not when administered into the MeA. This study identifies the DLS and the CeA as brain regions mediating the effects of NPY on the expression of social fear and suggests that partly distinct neural circuitries mediate the effects of NPY on the expression of social fear and on anxiety-like behavior.
Collapse
|
18
|
Bertocchi I, Mele P, Ferrero G, Oberto A, Carulli D, Eva C. NPY-Y1 receptor signaling controls spatial learning and perineuronal net expression. Neuropharmacology 2020; 184:108425. [PMID: 33285203 DOI: 10.1016/j.neuropharm.2020.108425] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 11/24/2020] [Accepted: 12/01/2020] [Indexed: 12/17/2022]
Abstract
Perineuronal nets (PNNs) are extracellular matrix structures that form around some types of neurons at the end of critical periods, limiting neuronal plasticity. In the adult brain, PNNs play a crucial role in the regulation of learning and cognitive processes. Neuropeptide Y (NPY) is involved in the regulation of many physiological functions, including learning and memory abilities, via activation of Y1 receptors (Y1Rs). Here we demonstrated that the conditional depletion of the gene encoding the Y1R for NPY in adult forebrain excitatory neurons (Npy1rrfb mutant mice), induces a significant slowdown in spatial learning, which is associated with a robust intensification of PNN expression and an increase in the number of c-Fos expressing cells in the cornus ammonis 1 (CA1) of the dorsal hippocampus. Importantly, the enzymatic digestion of PNNs in CA1 normalizes c-Fos activity and completely rescues learning abilities of Npy1rrfb mice. These data highlight a previously unknown functional link between NPY-Y1R transmission and PNNs, which may play a role in the control of dorsal hippocampal excitability and related cognitive functions.
Collapse
Affiliation(s)
- Ilaria Bertocchi
- Neuroscience Institute of the Cavalieri-Ottolenghi Foundation, 10043, Orbassano, Turin, Italy; Department of Neuroscience, University of Turin, 10126, Turin, Italy; Neuroscience Institute of Turin (NIT), Italy
| | - Paolo Mele
- Neuroscience Institute of the Cavalieri-Ottolenghi Foundation, 10043, Orbassano, Turin, Italy; Department of Neuroscience, University of Turin, 10126, Turin, Italy
| | - Giuliano Ferrero
- Neuroscience Institute of the Cavalieri-Ottolenghi Foundation, 10043, Orbassano, Turin, Italy
| | - Alessandra Oberto
- Neuroscience Institute of the Cavalieri-Ottolenghi Foundation, 10043, Orbassano, Turin, Italy; Department of Neuroscience, University of Turin, 10126, Turin, Italy; Neuroscience Institute of Turin (NIT), Italy
| | - Daniela Carulli
- Neuroscience Institute of the Cavalieri-Ottolenghi Foundation, 10043, Orbassano, Turin, Italy; Department of Neuroscience, University of Turin, 10126, Turin, Italy; Neuroscience Institute of Turin (NIT), Italy; Netherlands Institute for Neuroscience, 1105 BA, Amsterdam, Netherlands
| | - Carola Eva
- Neuroscience Institute of the Cavalieri-Ottolenghi Foundation, 10043, Orbassano, Turin, Italy; Department of Neuroscience, University of Turin, 10126, Turin, Italy; Neuroscience Institute of Turin (NIT), Italy.
| |
Collapse
|
19
|
Kornhuber J, Zoicas I. Neuropeptide Y as Alternative Pharmacotherapy for Antidepressant-Resistant Social Fear. Int J Mol Sci 2020; 21:ijms21218220. [PMID: 33153050 PMCID: PMC7662288 DOI: 10.3390/ijms21218220] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 10/30/2020] [Accepted: 10/31/2020] [Indexed: 12/25/2022] Open
Abstract
In many social anxiety disorder (SAD) patients, the efficacy of antidepressant therapy is unsatisfactory. Here, we investigated whether mice deficient for the lysosomal glycoprotein acid sphingomyelinase (ASM−/−) represent an appropriate tool to study antidepressant-resistant social fear. We also investigated whether neuropeptide Y (NPY) reduces this antidepressant-resistant social fear in ASM−/− mice, given that NPY reduced social fear in a mouse model of SAD, namely social fear conditioning (SFC). We show that neither chronic paroxetine nor chronic amitriptyline administration via drinking water were successful in reducing SFC-induced social fear in ASM−/− mice, while the same treatment reduced social fear in ASM+/− mice and completely reversed social fear in ASM+/+ mice. This indicates that the antidepressants paroxetine and amitriptyline reduce social fear via the ASM-ceramide system and that ASM−/− mice represent an appropriate tool to study antidepressant-resistant social fear. The intracerebroventricular administration of NPY, on the other hand, reduced social fear in ASM−/− mice, suggesting that NPY might represent an alternative pharmacotherapy for antidepressant-resistant social fear. These results suggest that medication strategies aimed at increasing brain NPY concentrations might improve symptoms of social fear in SAD patients who fail to respond to antidepressant treatments.
Collapse
|
20
|
Nahvi RJ, Sabban EL. Sex Differences in the Neuropeptide Y System and Implications for Stress Related Disorders. Biomolecules 2020; 10:biom10091248. [PMID: 32867327 PMCID: PMC7564266 DOI: 10.3390/biom10091248] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 08/25/2020] [Accepted: 08/26/2020] [Indexed: 12/16/2022] Open
Abstract
The neuropeptide Y (NPY) system is emerging as a promising therapeutic target for neuropsychiatric disorders by intranasal delivery to the brain. However, the vast majority of underlying research has been performed with males despite females being twice as susceptible to many stress-triggered disorders such as posttraumatic stress disorder, depression, anorexia nervosa, and anxiety disorders. Here, we review sex differences in the NPY system in basal and stressed conditions and how it relates to varied susceptibility to stress-related disorders. The majority of studies demonstrate that NPY expression in many brain areas under basal, unstressed conditions is lower in females than in males. This could put them at a disadvantage in dealing with stress. Knock out animals and Flinders genetic models show that NPY is important for attenuating depression in both sexes, while its effects on anxiety appear more pronounced in males. In females, NPY expression after exposure to stress may depend on age, timing, and nature and duration of the stressors and may be especially pronounced in the catecholaminergic systems. Furthermore, alterations in NPY receptor expression and affinity may contribute to the sex differences in the NPY system. Overall, the review highlights the important role of NPY and sex differences in manifestation of neuropsychiatric disorders.
Collapse
|
21
|
Serova LI, Hansson E, Sabban EL. Effect of intranasal administration of neuropeptide Y and single prolonged stress on food consumption and body weight in male rats. Neuropeptides 2020; 82:102060. [PMID: 32600666 DOI: 10.1016/j.npep.2020.102060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 06/12/2020] [Accepted: 06/15/2020] [Indexed: 01/30/2023]
Abstract
Emerging evidence indicates that intranasal delivery of neuropeptide Y (NPY) to the brain has therapeutic potential for management of stress-triggered neuropsychiatric disorders. Here we aimed to determine how intranasal administration of NPY, either before or immediately after, traumatic stress in single prolonged stress (SPS) rodent model of Post-traumatic stress disorder (PTSD) impacts food consumption and body weight. SPS stressors suppressed food consumption for at least two days in the vehicle-treated animals. When given prior to SPS stressors, intranasal NPY prevented the SPS-elicited reduction in food intake only for several hours afterwards. When given after the SPS stressors, under conditions shown to prevent behavioral and biochemical impairments, intranasal NPY had no effect on food intake. Although all groups showed circadian variation, the SPS-exposed rats ate less than unstressed animals during the dark (active) phase. Seven days after exposure to SPS stressors, there were no differences in food intake, although body weight was still lower than unstressed controls in all the experimental groups. Thus, traumatic stress has pronounced effect on food consumption during the rodent's active phase, and a prolonged effect on body weight. Single intranasal infusion of NPY, which was previously shown to prevent development of several PTSD associated behavioral and neuroendocrine impairments, did not elicit prolonged changes in stress triggered food consumption nor regulation of body weight.
Collapse
Affiliation(s)
- Lidia I Serova
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York 10595, USA
| | - Evelyn Hansson
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York 10595, USA
| | - Esther L Sabban
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York 10595, USA.
| |
Collapse
|
22
|
Kornhuber J, Zoicas I. Neuropeptide Y prolongs non-social memory in a brain region- and receptor-specific way in male mice. Neuropharmacology 2020; 175:108199. [PMID: 32535011 DOI: 10.1016/j.neuropharm.2020.108199] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 05/05/2020] [Accepted: 06/10/2020] [Indexed: 11/16/2022]
Abstract
Neuropeptide Y (NPY) and its receptors are highly expressed in brain regions involved in learning and memory processes. We have previously shown that intracerebroventricular administration of NPY prolongs the retention of non-social memory in the object discrimination test. Here, we aimed to identify the brain regions which mediate these memory-enhancing effects of NPY. We show that NPY (0.1 nmol/0.2 μl/side) prolongs retention of non-social memory when administered into the dorsolateral septum (DLS) and medial amygdala (MeA), but not when administered into the dorsal hippocampus, central amygdala and basolateral amygdala. In the DLS, the effects of NPY were blocked by the Y1 receptor antagonist BIBO3304 trifluoroacetate (0.2 nmol/0.2 μl/side), but not by the Y2 receptor antagonist BIIE0246 (0.2 nmol/0.2 μl/side). In the MeA, on the other hand, BIIE0246, but not BIBO3304 trifluoroacetate blocked the effects of NPY. This study demonstrates that NPY exerts Y1 receptor-mediated memory-enhancing effects in the DLS and Y2 receptor-mediated memory-enhancing effects in the MeA, and suggests that distinct brain regions and receptor subtypes are recruited to mediate the effects of NPY on non-social memory.
Collapse
Affiliation(s)
- Johannes Kornhuber
- Department of Psychiatry and Psychotherapy, University Hospital, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany.
| | - Iulia Zoicas
- Department of Psychiatry and Psychotherapy, University Hospital, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany.
| |
Collapse
|
23
|
Kim BK, Fonda JR, Hauger RL, Pinna G, Anderson GM, Valovski IT, Rasmusson AM. Composite contributions of cerebrospinal fluid GABAergic neurosteroids, neuropeptide Y and interleukin-6 to PTSD symptom severity in men with PTSD. Neurobiol Stress 2020; 12:100220. [PMID: 32435669 PMCID: PMC7231970 DOI: 10.1016/j.ynstr.2020.100220] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 03/31/2020] [Accepted: 04/04/2020] [Indexed: 02/06/2023] Open
Abstract
Given that multiple neurobiological systems, as well as components within these systems are impacted by stress, and may interact in additive, compensatory and synergistic ways to promote or mitigate PTSD risk, severity, and recovery, we thought that it would be important to consider the collective, as well as separate effects of these neurobiological systems on PTSD risk. With this goal in mind, we conducted a proof-of-concept study utilizing cerebrospinal fluid (CSF) collected from unmedicated, tobacco- and illicit substance-free men with PTSD (n = 13) and trauma-exposed healthy controls (TC) (n = 17). Thirteen neurobiological factors thought to contribute to PTSD risk or severity based on previous studies were assayed. As the small but typical sample size of this lumbar puncture study limited the number of factors that could be considered in a hierarchical regression model, we included only those five factors with at least a moderate correlation (Spearman rho > 0.30) with total Clinician-Administered PTSD Scale (CAPS-IV) scores, and that did not violate multicollinearity criteria. Three of the five factors meeting these criteria—CSF allopregnanolone and pregnanolone (Allo + PA: equipotent GABAergic metabolites of progesterone), neuropeptide Y (NPY), and interleukin-6 (IL-6)—were found to account for over 75% of the variance in the CAPS-IV scores (R2 = 0.766, F = 8.75, p = 0.007). CSF Allo + PA levels were negatively associated with PTSD severity (β = −0.523, p = 0.02) and accounted for 47% of the variance in CAPS-IV scores. CSF NPY was positively associated with PTSD severity (β = 0.410, p = 0.04) and accounted for 14.7% of the CAPS-IV variance. There was a trend for a positive association between PTSD severity and CSF IL-6 levels, which accounted for 15.3% of the variance in PTSD severity (β = 0.423, p = 0.05). Z-scores were then computed for each of the three predictive factors and used to depict the varying relative degrees to which each contributed to PTSD severity at the individual PTSD patient level. This first of its kind, proof-of-concept study bears replication in larger samples. However, it highlights the collective effects of dysregulated neurobiological systems on PTSD symptom severity and the heterogeneity of potential biological treatment targets across individual PTSD patients—thus supporting the need for precision medicine approaches to treatment development and prescribing in PTSD.
Collapse
Key Words
- 3α-HSD, 3α-hydroxysteroid dehydrogenase
- Allo + PA, sum of allopregnanolone and pregnanolone
- EIA, enzyme immunoassay
- GC-MS, gas chromatography-mass spectrometry
- HPLC, high pressure liquid chromatography
- LP, lumbar puncture
- PE, prolonged exposure therapy
- PFC, prefrontal cortex
- RIA, radioimmunoassay
- TC, trauma-exposed control
Collapse
Affiliation(s)
- Byung Kil Kim
- VA Boston Healthcare System, 150 South Huntington Ave., Boston, MA, 02130, USA
| | - Jennifer R Fonda
- VA Boston Healthcare System, 150 South Huntington Ave., Boston, MA, 02130, USA.,Translational Research Center for TBI and Stress Disorders (TRACTS) and Geriatric Research, Education and Clinical Center (GRECC), 150 South Huntington Ave., Boston, MA, 02130, USA.,Boston University School of Medicine, 72 E. Concord Street, Boston, MA, 02118, USA
| | - Richard L Hauger
- Center of Excellence for Stress and Mental Health, VA San Diego Healthcare System, 3350 La Jolla Village Drive, San Diego, CA, 92161, USA.,Center for Behavior Genetics of Aging, Department of Psychiatry, School of Medicine, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - Graziano Pinna
- The Psychiatric Institute, College of Medicine, University of Illinois at Chicago, 1601 W Taylor St. MC912 Chicago, IL, 60612, USA
| | - George M Anderson
- Child Study Center and Department of Laboratory Medicine, Yale University School of Medicine S. Frontage Rd. New Haven, CT, 06519, USA
| | - Ivan T Valovski
- VA Boston Healthcare System, 150 South Huntington Ave., Boston, MA, 02130, USA.,Harvard Medical School, 25 Shattuck St. Boston, MA, 02115, USA
| | - Ann M Rasmusson
- VA Boston Healthcare System, 150 South Huntington Ave., Boston, MA, 02130, USA.,Boston University School of Medicine, 72 E. Concord Street, Boston, MA, 02118, USA.,VA National Center for PTSD Women's Health Science Division, 150 South Huntington Ave., Boston, MA, 02130, USA
| |
Collapse
|
24
|
Michaelson SD, Miranda Tapia AP, McKinty A, Silveira Villarroel H, Mackay JP, Urban JH, Colmers WF. Contribution of NPY Y 5 Receptors to the Reversible Structural Remodeling of Basolateral Amygdala Dendrites in Male Rats Associated with NPY-Mediated Stress Resilience. J Neurosci 2020; 40:3231-3249. [PMID: 32144180 PMCID: PMC7159890 DOI: 10.1523/jneurosci.2621-19.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 02/21/2020] [Accepted: 02/27/2020] [Indexed: 11/21/2022] Open
Abstract
Endogenous neuropeptide Y (NPY) and corticotrophin-releasing factor (CRF) modulate the responses of the basolateral amygdala (BLA) to stress and are associated with the development of stress resilience and vulnerability, respectively. We characterized persistent effects of repeated NPY and CRF treatment on the structure and function of BLA principal neurons in a novel organotypic slice culture (OTC) model of male rat BLA, and examined the contributions of specific NPY receptor subtypes to these neural and behavioral effects. In BLA principal neurons within the OTCs, repeated NPY treatment caused persistent attenuation of excitatory input and induced dendritic hypotrophy via Y5 receptor activation; conversely, CRF increased excitatory input and induced hypertrophy of BLA principal neurons. Repeated treatment of OTCs with NPY followed by an identical treatment with CRF, or vice versa, inhibited or reversed all structural changes in OTCs. These structural responses to NPY or CRF required calcineurin or CaMKII, respectively. Finally, repeated intra-BLA injections of NPY or a Y5 receptor agonist increased social interaction, a validated behavior for anxiety, and recapitulated structural changes in BLA neurons seen in OTCs, while a Y5 receptor antagonist prevented NPY's effects both on behavior and on structure. These results implicate the Y5 receptor in the long-term, anxiolytic-like effects of NPY in the BLA, consistent with an intrinsic role in stress buffering, and highlight a remarkable mechanism by which BLA neurons may adapt to different levels of stress. Moreover, BLA OTCs offer a robust model to study mechanisms associated with resilience and vulnerability to stress in BLA.SIGNIFICANCE STATEMENT Within the basolateral amygdala (BLA), neuropeptide Y (NPY) is associated with buffering the neural stress response induced by corticotropin releasing factor, and promoting stress resilience. We used a novel organotypic slice culture model of BLA, complemented with in vivo studies, to examine the cellular mechanisms associated with the actions of NPY. In organotypic slice cultures, repeated NPY treatment reduces the complexity of the dendritic extent of anxiogenic BLA principal neurons, making them less excitable. NPY, via activation of Y5 receptors, additionally inhibits and reverses the increases in dendritic extent and excitability induced by the stress hormone, corticotropin releasing factor. This NPY-mediated neuroplasticity indicates that resilience or vulnerability to stress may thus involve neuropeptide-mediated dendritic remodeling in BLA principal neurons.
Collapse
Affiliation(s)
- Sheldon D Michaelson
- Department of Pharmacology, and the Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta T6G 2H7, Canada, and
| | - Ana Pamela Miranda Tapia
- Department of Pharmacology, and the Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta T6G 2H7, Canada, and
| | - Amanda McKinty
- Department of Pharmacology, and the Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta T6G 2H7, Canada, and
| | - Heika Silveira Villarroel
- Department of Pharmacology, and the Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta T6G 2H7, Canada, and
| | - James P Mackay
- Department of Pharmacology, and the Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta T6G 2H7, Canada, and
| | - Janice H Urban
- Center for the Neurobiology of Stress Resilience and Psychiatric Disorders, Discipline of Physiology and Biophysics, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois 60064
| | - William F Colmers
- Department of Pharmacology, and the Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta T6G 2H7, Canada, and
| |
Collapse
|
25
|
Nwokafor C, Serova LI, Nahvi RJ, McCloskey J, Sabban EL. Activation of NPY receptor subtype 1 by [D-His 26]NPY is sufficient to prevent development of anxiety and depressive like effects in the single prolonged stress rodent model of PTSD. Neuropeptides 2020; 80:102001. [PMID: 31916978 DOI: 10.1016/j.npep.2019.102001] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 11/17/2019] [Accepted: 12/20/2019] [Indexed: 12/18/2022]
Abstract
The neuropeptide Y (NPY) system plays an important role in mediating resilience to the harmful effect of stress in post-traumatic stress disorder (PTSD). It can mediate its effects via several G-protein coupled receptors: Y1R, Y2R, Y4R and Y5R. To investigate the role of individual NPY receptors in the resilience effects of NPY to traumatic stress, intranasal infusion of either Y1R agonists [D-His26]NPY, [Leu31Pro34]NPY, Y2R agonist NPY (3-36) or NPY were administered to male Sprague-Dawley rats immediately following the last stressor of the single prolonged stress (SPS) protocol, a widely used PTSD animal model. After 7 or 14 days, effects of the treatments were measured on the elevated plus maze (EPM) for anxiety, in forced swim test (FST) for development of depressive-like or re-experiencing behavior, in social interaction (SI) test for impaired social behavior, and acoustic startle response (ASR) for hyperarousal. [D-His26]NPY, but not [Leu31Pro34]NPY nor NPY (3-36) Y2R, was effective in preventing the SPS-elicited development of anxiety. Y1R, but not Y2R agonists prevented development of depressive- feature on FST, with [D-His26]NPY superior to NPY. The results demonstrate that [D-His26]NPY was sufficient to prevent development of anxiety, social impairment and depressive symptoms, and has promise as an early intervention therapy following traumatic stress.
Collapse
Affiliation(s)
- Chiso Nwokafor
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, USA
| | - Lidia I Serova
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, USA
| | - Roxanna J Nahvi
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, USA
| | - Jaclyn McCloskey
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, USA
| | - Esther L Sabban
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, USA.
| |
Collapse
|
26
|
Kornhuber J, Zoicas I. Neuropeptide Y reduces expression of social fear via simultaneous activation of Y1 and Y2 receptors. J Psychopharmacol 2019; 33:1533-1539. [PMID: 31328614 PMCID: PMC6854880 DOI: 10.1177/0269881119862529] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Neuropeptide Y (NPY) has anxiolytic effects and facilitates extinction of cued and contextual fear in rodents, thereby acting as a resilience factor against exaggerated fear responses after adverse events. We investigated whether NPY influences acquisition, expression and extinction of social fear in a mouse model of social fear conditioning (SFC). METHODS NPY was administered intracerebroventricularly before SFC or before social fear extinction with or without prior administration of Y1 and/or Y2 receptor antagonists. RESULTS We show that NPY affects SFC-induced social fear in a time point-dependent manner. When administered before SFC, NPY did not affect acquisition, expression and extinction of social fear. However, when administered before social fear extinction, NPY reduced expression of social fear via simultaneous activation of Y1 and Y2 receptors. As such, neither the Y1 receptor antagonist BIBO3304 trifluoroacetate nor the Y2 receptor antagonist BIIE0246 was able to block the effects of NPY completely. However, when administered in combination, they completely blocked the effects of NPY on social fear expression. CONCLUSIONS These findings have important clinical implications, as they suggest that although medication strategies aimed at increasing brain NPY activity are unlikely to prevent the formation of aversive memories after a traumatic social experience, they might improve the recovery from a traumatic social experience by reducing the expression of social fear.
Collapse
Affiliation(s)
| | - Iulia Zoicas
- Iulia Zoicas, Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University Erlangen-Nürnberg, Schwabachanlage 6, Erlangen 91054, Germany.
| |
Collapse
|
27
|
Excitation of Diverse Classes of Cholecystokinin Interneurons in the Basal Amygdala Facilitates Fear Extinction. eNeuro 2019; 6:ENEURO.0220-19.2019. [PMID: 31636080 PMCID: PMC6838687 DOI: 10.1523/eneuro.0220-19.2019] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 09/19/2019] [Accepted: 09/30/2019] [Indexed: 01/25/2023] Open
Abstract
There is growing evidence that interneurons (INs) orchestrate neural activity and plasticity in corticoamygdala circuits to regulate fear behaviors. However, defining the precise role of cholecystokinin-expressing INs (CCK INs) remains elusive due to the technical challenge of parsing this population from CCK-expressing principal neurons (CCK PNs). Here, we used an intersectional genetic strategy in CCK-Cre;Dlx5/6-Flpe double-transgenic mice to study the anatomical, molecular and electrophysiological properties of CCK INs in the basal amygdala (BA) and optogenetically manipulate these cells during fear extinction. Electrophysiological recordings confirmed that this strategy targeted GABAergic cells and that a significant proportion expressed functional cannabinoid CB1 receptors; a defining characteristic of CCK-expressing basket cells. However, immunostaining showed that subsets of the genetically-targeted cells expressed either neuropeptide Y (NPY; 29%) or parvalbumin (PV; 17%), but not somatostatin (SOM) or Ca2+/calmodulin-dependent protein kinase II (CaMKII)-α. Further morphological and electrophysiological analyses showed that four IN types could be identified among the EYFP-expressing cells: CCK/cannabinoid receptor type 1 (CB1R)-expressing basket cells, neurogliaform cells, PV+ basket cells, and PV+ axo-axonic cells. At the behavioral level, in vivo optogenetic photostimulation of the targeted population during extinction acquisition led to reduced freezing on a light-free extinction retrieval test, indicating extinction memory facilitation; whereas photosilencing was without effect. Conversely, non-selective (i.e., inclusive of INs and PNs) photostimulation or photosilencing of CCK-targeted cells, using CCK-Cre single-transgenic mice, impaired extinction. These data reveal an unexpectedly high degree of phenotypic complexity in a unique population of extinction-modulating BA INs.
Collapse
|
28
|
Comeras LB, Herzog H, Tasan RO. Neuropeptides at the crossroad of fear and hunger: a special focus on neuropeptide Y. Ann N Y Acad Sci 2019; 1455:59-80. [PMID: 31271235 PMCID: PMC6899945 DOI: 10.1111/nyas.14179] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 05/15/2019] [Accepted: 06/03/2019] [Indexed: 12/11/2022]
Abstract
Survival in a natural environment forces an individual into constantly adapting purposive behavior. Specified interoceptive neurons monitor metabolic and physiological balance and activate dedicated brain circuits to satisfy essential needs, such as hunger, thirst, thermoregulation, fear, or anxiety. Neuropeptides are multifaceted, central components within such life‐sustaining programs. For instance, nutritional depletion results in a drop in glucose levels, release of hormones, and activation of hypothalamic and brainstem neurons. These neurons, in turn, release several neuropeptides that increase food‐seeking behavior and promote food intake. Similarly, internal and external threats activate neuronal pathways of avoidance and defensive behavior. Interestingly, specific nuclei of the hypothalamus and extended amygdala are activated by both hunger and fear. Here, we introduce the relevant neuropeptides and describe their function in feeding and emotional‐affective behaviors. We further highlight specific pathways and microcircuits, where neuropeptides may interact to identify prevailing homeostatic needs and direct respective compensatory behaviors. A specific focus will be on neuropeptide Y, since it is known for its pivotal role in metabolic and emotional pathways. We hypothesize that the orexigenic and anorexigenic properties of specific neuropeptides are related to their ability to inhibit fear and anxiety.
Collapse
Affiliation(s)
- Lucas B Comeras
- Department of Pharmacology, Medical University Innsbruck, Innsbruck, Austria
| | - Herbert Herzog
- Neuroscience Division, Garvan Institute of Medical Research, Sydney, New South Wales, Australia
| | - Ramon O Tasan
- Department of Pharmacology, Medical University Innsbruck, Innsbruck, Austria
| |
Collapse
|
29
|
NPY 2 Receptors Reduce Tonic Action Potential-Independent GABA B Currents in the Basolateral Amygdala. J Neurosci 2019; 39:4909-4930. [PMID: 30971438 DOI: 10.1523/jneurosci.2226-18.2019] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 03/29/2019] [Accepted: 04/01/2019] [Indexed: 01/17/2023] Open
Abstract
Although NPY has potent anxiolytic actions within the BLA, selective activation of BLA NPY Y2 receptors (Y2Rs) acutely increases anxiety by an unknown mechanism. Using ex vivo male rat brain slice electrophysiology, we show that the selective Y2R agonist, [ahx5-24]NPY, reduced the frequency of GABAA-mediated mIPSCs in BLA principal neurons (PNs). [ahx5-24]NPY also reduced tonic activation of GABAB receptors (GABABR), which increased PN excitability through inhibition of a tonic, inwardly rectifying potassium current (KIR ). Surprisingly, Y2R-sensitive GABABR currents were action potential-independent, persisting after treatment with TTX. Additionally, the Ca2+-dependent, slow afterhyperpolarizing K+ current (IsAHP ) was enhanced in approximately half of the Y2R-sensitive PNs, possibly from enhanced Ca2+ influx, permitted by reduced GABABR tone. In male and female mice expressing tdTomato in Y2R-mRNA cells (tdT-Y2R mice), immunohistochemistry revealed that BLA somatostatin interneurons express Y2Rs, as do a significant subset of BLA PNs. In tdT-Y2R mice, [ahx5-24]NPY increased excitability and suppressed the KIR in nearly all BLA PNs independent of tdT-Y2R fluorescence, consistent with presynaptic Y2Rs on somatostatin interneurons mediating the above effects. However, only tdT-Y2R-expressing PNs responded to [ahx5-24]NPY with an enhancement of the IsAHP Ultimately, increased PN excitability via acute Y2R activation likely correlates with enhanced BLA output, consistent with reported Y2R-mediated anxiogenesis. Furthermore, we demonstrate the following: (1) a novel mechanism whereby activity-independent GABA release can powerfully dampen BLA neuronal excitability via postsynaptic GABABRs; and (2) that this tonic inhibition can be interrupted by neuromodulation, here by NPY via Y2Rs.SIGNIFICANCE STATEMENT Within the BLA, NPY is potently anxiolytic. However, selective activation of NPY2 receptors (Y2Rs) increases anxiety by an unknown mechanism. We show that activation of BLA Y2Rs decreases tonic GABA release onto BLA principal neurons, probably from Y2R-expressing somatostatin interneurons, some of which coexpress NPY. This increases principal neuron excitability by reducing GABAB receptor (GABABR)-mediated activation of G-protein-coupled, inwardly rectifying K+ currents. Tonic, Y2R-sensitive GABABR currents unexpectedly persisted in the absence of action potential firing, revealing, to our knowledge, the first report of substantial, activity-independent GABABR activation. Ultimately, we provide a plausible explanation for Y2R-mediated anxiogenesis in vivo and describe a novel and modulatable means of damping neuronal excitability.
Collapse
|
30
|
Sabban EL, Serova LI. Potential of Intranasal Neuropeptide Y (NPY) and/or Melanocortin 4 Receptor (MC4R) Antagonists for Preventing or Treating PTSD. Mil Med 2019; 183:408-412. [PMID: 29635611 DOI: 10.1093/milmed/usx228] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 01/18/2018] [Indexed: 02/02/2023] Open
Abstract
There is a great need for effective treatment options for post-traumatic stress disorder (PTSD). Neuropeptide Y (NPY) is associated with resilience to traumatic stress. MC4R antagonists, such as HS014, also reduce response to stress. Both regulate stress-responsive systems - the hypothalamic-pituitary-axis (HPA) and the noradrenergic nervous system and their associated behaviors. Therefore, we examined if their intranasal delivery to brain could attenuate development of PTSD-related symptoms in single prolonged stress (SPS) rodent PTSD model. Three regimens were used: (1) prophylactic treatment 30 min before SPS stressors, (2) early intervention right after SPS stressors, (3) therapeutic treatment when PTSD behaviors are manifested 1 wk or more after the traumatic stress. NPY delivered by regimen 1 or 2 prevented SPS-triggered elevation in anxiety, depressive-like behavior, and hyperarousal and reduced dysregulation of HPA axis. Hypothalamic CRH mRNA and GR in ventral hippocampus were significantly induced in vehicle- but not NPY-treated group. NPY also prevented hypersensitivity of LC/NE system to novel mild stressor and induction of CRH in amygdala. Some of these impairments were also reduced with HS014, alone or together with NPY. When given after symptoms were manifested (regiment 3), NPY attenuated anxiety and depressive behaviors. This demonstrates strong preclinical proof of concept for intranasal NPY, and perhaps MC4R antagonists, for non-invasive early pharmacological interventions for PTSD and comorbid disorders and possibly also as therapeutic strategy.
Collapse
Affiliation(s)
- Esther L Sabban
- Department of Biochemistry and Molecular Biology, New York Medical College, 15 Dana Road, Valhalla, NY 10595
| | - Lidia I Serova
- Department of Biochemistry and Molecular Biology, New York Medical College, 15 Dana Road, Valhalla, NY 10595
| |
Collapse
|
31
|
Ch'ng S, Fu J, Brown RM, McDougall SJ, Lawrence AJ. The intersection of stress and reward: BNST modulation of aversive and appetitive states. Prog Neuropsychopharmacol Biol Psychiatry 2018; 87:108-125. [PMID: 29330137 DOI: 10.1016/j.pnpbp.2018.01.005] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 12/27/2017] [Accepted: 01/08/2018] [Indexed: 12/13/2022]
Abstract
The bed nucleus of the stria terminalis (BNST) is widely acknowledged as a brain structure that regulates stress and anxiety states, as well as aversive and appetitive behaviours. The diverse roles of the BNST are afforded by its highly modular organisation, neurochemical heterogeneity, and complex intrinsic and extrinsic circuitry. There has been growing interest in the BNST in relation to psychopathologies such as anxiety and addiction. Although research on the human BNST is still in its infancy, there have been extensive preclinical studies examining the molecular signature and hodology of the BNST and their involvement in stress and reward seeking behaviour. This review examines the neurochemical phenotype and connectivity of the BNST, as well as electrophysiological correlates of plasticity in the BNST mediated by stress and/or drugs of abuse.
Collapse
Affiliation(s)
- Sarah Ch'ng
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria 3052, Australia
| | - Jingjing Fu
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria 3052, Australia
| | - Robyn M Brown
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria 3052, Australia
| | - Stuart J McDougall
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria 3052, Australia
| | - Andrew J Lawrence
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria 3052, Australia.
| |
Collapse
|
32
|
Hippocampal NPY Y2 receptors modulate memory depending on emotional valence and time. Neuropharmacology 2018; 143:20-28. [DOI: 10.1016/j.neuropharm.2018.09.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 08/29/2018] [Accepted: 09/11/2018] [Indexed: 12/13/2022]
|
33
|
Neuropeptide Y impairs the acquisition of conditioned defeat in Syrian hamsters. Neurosci Lett 2018; 690:214-218. [PMID: 30312751 DOI: 10.1016/j.neulet.2018.09.049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 09/10/2018] [Accepted: 09/25/2018] [Indexed: 12/12/2022]
Abstract
Recent evidence indicates that Neuropeptide Y (NPY) may function as a potent anxiolytic as well as a resilience factor that can insulate the brain from the effects of stress. However, most of these studies have utilized physical stressors such as shock or restraint. In the present study, we use an ethologically-based model in Syrian hamsters (Mesocricetus auratus) called Conditioned Defeat (CD) to investigate whether NPY can ameliorate the effect of social defeat stress. In the CD model, a male Syrian hamster is socially defeated by a larger, more aggressive conspecific. Subsequently, when paired with a smaller, non-aggressive intruder (NAI) in its own home cage, changes in its behavioral repertoire occur, including a reduction in aggression and chemosensory (social) investigation, and a concomitant increase in submissive behaviors. In Experiment 1, hamsters were infused intracerebroventricularly (icv) with NPY prior to social defeat, and 24-hours later, hamsters were exposed to a NAI. Results indicate that NPY significantly reduced submissive/defensive behaviors in socially defeated hamsters compared to control animals. In Experiment 2, we examined whether this effect was mediated by the NPY Y1 receptor. Subjects were first pre-treated with the Y1 receptor antagonist BIBP 3226 or vehicle, followed by NPY and then socially defeated. Upon testing with a NAI 24-hours later, pretreatment with BIBP 3226 failed to block the NPY effect compared to controls. These results demonstrate that NPY may function as an important resilience factor in socially defeated hamsters, but that these effects are not mediated by the Y1 receptor.
Collapse
|
34
|
Neurotransmitter, Peptide, and Steroid Hormone Abnormalities in PTSD: Biological Endophenotypes Relevant to Treatment. Curr Psychiatry Rep 2018; 20:52. [PMID: 30019147 DOI: 10.1007/s11920-018-0908-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
PURPOSE OF REVIEW This review summarizes neurotransmitter, peptide, and other neurohormone abnormalities associated with posttraumatic stress disorder (PTSD) and relevant to development of precision medicine therapeutics for PTSD. RECENT FINDINGS As the number of molecular abnormalities associated with PTSD across a variety of subpopulations continues to grow, it becomes clear that no single abnormality characterizes all individuals with PTSD. Instead, individually variable points of molecular dysfunction occur within several different stress-responsive systems that interact to produce the clinical PTSD phenotype. Future work should focus on critical interactions among the systems that influence PTSD risk, severity, chronicity, comorbidity, and response to treatment. Effort also should be directed toward development of clinical procedures by which points of molecular dysfunction within these systems can be identified in individual patients. Some molecular abnormalities are more common than others and may serve as subpopulation biological endophenotypes for targeting of currently available and novel treatments.
Collapse
|
35
|
Silveira Villarroel H, Bompolaki M, Mackay JP, Miranda Tapia AP, Michaelson SD, Leitermann RJ, Marr RA, Urban JH, Colmers WF. NPY Induces Stress Resilience via Downregulation of Ih in Principal Neurons of Rat Basolateral Amygdala. J Neurosci 2018; 38:4505-4520. [PMID: 29650696 PMCID: PMC5943978 DOI: 10.1523/jneurosci.3528-17.2018] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 03/01/2018] [Accepted: 04/05/2018] [Indexed: 01/26/2023] Open
Abstract
Neuropeptide Y (NPY) expression is tightly linked with the development of stress resilience in rodents and humans. Local NPY injections targeting the basolateral amygdala (BLA) produce long-term behavioral stress resilience in male rats via an unknown mechanism. Previously, we showed that activation of NPY Y1 receptors hyperpolarizes BLA principal neurons (PNs) through inhibition of the hyperpolarization-activated, depolarizing H-current, Ih The present studies tested whether NPY treatment induces stress resilience by modulating Ih NPY (10 pmol) was delivered daily for 5 d bilaterally into the BLA to induce resilience; thereafter, the electrophysiological properties of PNs and the expression of Ih in the BLA were characterized. As reported previously, increases in social interaction (SI) times persisted weeks after completion of NPY administration. In vitro intracellular recordings showed that repeated intra-BLA NPY injections resulted in hyperpolarization of BLA PNs at 2 weeks (2W) and 4 weeks (4W) after NPY treatment. At 2W, spontaneous IPSC frequencies were increased, whereas at 4W, resting Ih was markedly reduced and accompanied by decreased levels of HCN1 mRNA and protein expression in BLA. Knock-down of HCN1 channels in the BLA with targeted delivery of lentivirus containing HCN1-shRNA increased SI beginning 2W after injection and induced stress resilience. NPY treatment induced sequential, complementary changes in the inputs to BLA PNs and their postsynaptic properties that reduce excitability, a mechanism that contributes to less anxious behavior. Furthermore, HCN1 knock-down mimicked the increases in SI and stress resilience observed with NPY, indicating the importance of Ih in stress-related behavior.SIGNIFICANCE STATEMENT Resilience improves mental health outcomes in response to adverse situations. Neuropeptide Y (NPY) is associated with decreased stress responses and the expression of resilience in rodents and humans. Single or repeated injections of NPY into the basolateral amygdala (BLA) buffer negative behavioral effects of stress and induce resilience in rats, respectively. Here, we demonstrate that repeated administration of NPY into the BLA unfolds several cellular mechanisms that decrease the activity of pyramidal output neurons. One key mechanism is a reduction in levels of the excitatory ion channel HCN1. Moreover, shRNA knock-down of HCN1 expression in BLA recapitulates some of the actions of NPY and causes potent resilience to stress, indicating that this channel may be a possible target for therapy.
Collapse
Affiliation(s)
| | | | - James P Mackay
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada T6G 2H7
| | | | - Sheldon D Michaelson
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada T6G 2H7
| | | | - Robert A Marr
- Department of Neuroscience, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois 60064
| | | | - William F Colmers
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada T6G 2H7,
| |
Collapse
|
36
|
Verma D, Tasan R, Sperk G, Pape HC. Neuropeptide Y2 receptors in anteroventral BNST control remote fear memory depending on extinction training. Neurobiol Learn Mem 2018; 149:144-153. [PMID: 29408468 DOI: 10.1016/j.nlm.2018.01.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 12/15/2017] [Accepted: 01/23/2018] [Indexed: 12/12/2022]
Abstract
The anterior bed nucleus of stria terminalis (BNST) is involved in reinstatement of extinguished fear, and neuropeptide Y2 receptors influence local synaptic signaling. Therefore, we hypothesized that Y2 receptors in anteroventral BNST (BNSTav) interfere with remote fear memory and that previous fear extinction is an important variable. C57BL/6NCrl mice were fear-conditioned, and a Y2 receptor-specific agonist (NPY3-36) or antagonist (JNJ-5207787) was applied in BNSTav before fear retrieval at the following day. Remote fear memory was tested on day 16 in two groups of mice, which had (experiment 1) or had not (experiment 2) undergone extinction training after conditioning. In the group with extinction training, tests of remote fear memory revealed partial retrieval of extinction, which was prevented after blockade of Y2 receptors in BNSTav. No such effect was observed in the group with no extinction training, but stimulation of Y2 receptors in BNSTav mimicked the influence of extinction during tests of remote fear memory. Pharmacological manipulation of Y2 receptors in BNSTav before fear acquisition (experiment 3) had no effect on fear memory retrieval, extinction or remote fear memory. Furthermore, partial retrieval of extinction during tests of remote fear memory was associated with changes in number of c-Fos expressing neurons in BNSTav, which was prevented or mimicked upon Y2 blockade or stimulation in BNSTav. These results indicate that Y2 receptor manipulation in BNSTav interferes with fear memory and extinction retrieval at remote stages, likely through controlling neuronal activity in BNSTav during extinction training.
Collapse
Affiliation(s)
- Dilip Verma
- Institute of Physiology 1, Westfälische Wilhelms-University, D-48149 Münster, Germany
| | - Ramon Tasan
- Institute of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - Guenther Sperk
- Institute of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - Hans-Christian Pape
- Institute of Physiology 1, Westfälische Wilhelms-University, D-48149 Münster, Germany.
| |
Collapse
|
37
|
Camp R, Stier CT, Serova LI, McCloskey J, Edwards JG, Reyes-Zaragoza M, Sabban EL. Cardiovascular responses to intranasal neuropeptide Y in single prolonged stress rodent model of post-traumatic stress disorder. Neuropeptides 2018; 67:87-94. [PMID: 29169656 DOI: 10.1016/j.npep.2017.11.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 10/26/2017] [Accepted: 11/08/2017] [Indexed: 01/25/2023]
Abstract
Delivery of neuropeptide Y (NPY) to the brain by intranasal administration shows promise as non-invasive means for preventing or treating PTSD symptoms. Here, radiotelemetry and echocardiography were used to determine effects of intranasal NPY on cardiovascular functions in absence and presence of stress. Male adult Sprague Dawley rats were implanted with radiotelemetric probes, and subjected to single prolonged stress (SPS), followed by intranasal vehicle (V) or NPY (150μg) under conditions shown to prevent development of many of the behavioral neuroendocrine and biochemical impairments. In both groups, mean arterial pressure (MAP) rose rapidly peaking at about 125mmHg, remaining near maximal levels for 1h. SPS also elicited robust rise in heart rate (HR) which was mitigated by intranasal NPY, and significantly lower than V-treated rats 12-50min after exposure to SPS stressors. In the first hr. after SPS, locomotor activity was elevated but only in the V-treated group. By 3h, MAP returned to pre-stress levels in both groups with no further change when monitored for 6days. HR remained elevated during the 6h remaining light phase after SPS. Subsequently HR was at pre-SPS levels during the remaining days. However dark phase HR was low following SPS, gradually recovered over 6days and was associated with reduced activity. When administered in the absence of further stress, intranasal NPY or V elicited similar much smaller, short-lived rises in MAP and HR. Echocardiography revealed no change in HR, stroke volume (SV) or cardiac output (Q) with intranasal NPY in the absence of stress. SPS led to reduced SV and Q but was not affected by NPY. Overall the results demonstrate no major cardiovascular effects of intranasal NPY and indicate possible benefit from transient amelioration of HR response in line with its translational potential to combat PTSD and comorbid impairments.
Collapse
Affiliation(s)
- Robert Camp
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York 10595, USA
| | - Charles T Stier
- Department of Pharmacology, New York Medical College, Valhalla, New York 10595, USA
| | - Lidia I Serova
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York 10595, USA
| | - Jaclyn McCloskey
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York 10595, USA
| | - John G Edwards
- Department of Physiology, New York Medical College, Valhalla, New York 10595, USA
| | - Miguel Reyes-Zaragoza
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York 10595, USA
| | - Esther L Sabban
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York 10595, USA.
| |
Collapse
|
38
|
Changes in Gene Expression in the Locus Coeruleus-Amygdala Circuitry in Inhibitory Avoidance PTSD Model. Cell Mol Neurobiol 2017; 38:273-280. [PMID: 28889197 DOI: 10.1007/s10571-017-0548-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 09/02/2017] [Indexed: 12/28/2022]
Abstract
The locus coeruleus (LC)-amygdala circuit is implicated in playing a key role in responses to emotionally arousing stimuli and in the manifestation of post-traumatic stress disorder (PTSD). Here, we examined changes in gene expression of a number of important mediators of the LC-amygdala circuitry in the inhibition avoidance model of PTSD. After testing for basal acoustic startle response (ASR), rats were exposed to a severe footshock (1.5 mA for 10 s) in the inhibitory avoidance apparatus. They were given contextual situational reminders every 5 day for 25 days. Controls were treated identically but with the footshock inactivated. Animals were re-tested on second ASR and decapitated 1 h later. The shock group had enhanced hyperarousal and several changes in gene expression compared to controls. In the LC, mRNA levels of norepinephrine (NE) biosynthetic enzymes (TH, DBH), NE transporter (NET), NPY receptors (Y1R, Y2R), and CB1 receptor of endocannabinoid system were elevated. In the basolateral amygdala (BLA), there were marked reductions in gene expression for CB1, and especially Y1R, with rise for corticotropin-releasing hormone (CRH) system (CRH, CRH receptor 1), and no significant changes in the central amygdala. Our results suggest a fast forward mechanism in the LC-amygdala circuitry in the shock group.
Collapse
|
39
|
Melhorn SJ, Elfers CT, Scott KA, Sakai RR. A closer look at the subordinate population within the visible burrow system. Physiol Behav 2017; 178:110-116. [PMID: 28130085 PMCID: PMC5513744 DOI: 10.1016/j.physbeh.2017.01.039] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 01/11/2017] [Accepted: 01/23/2017] [Indexed: 02/05/2023]
Abstract
The visible burrow system (VBS) utilizes the natural social behavior of rodents to model chronic social stress. Classically, when male and female rats are housed together in the VBS a dominance hierarchy rapidly forms with one dominant (DOM) and three subordinate (SUB) males. SUB animals show signs of chronic social stress, including loss of body weight and elevated basal corticosterone. This study furthered examined differences among the SUB population. Quantitative observations across numerous VBS colonies within the Sakai Lab suggest that there is variability in the effects of stress on the SUB population, specifically that some animals may experience more severe effects of chronic social stress than others. To further examine this observation, SUB animals were classified as OMEGA if they received a disproportionate amount of their colonies' wounds. OMEGA animals received more wounds to their body compared to SUB (P<0.0001) and lost significantly more weight throughout the stress period compared to all other VBS-housed animals (group×time interaction P<0.0001). Following VBS housing it was determined the OMGEA also lost lean body mass (P<0.01 vs. controls and DOM), are hyporesponsive to an acute restraint challenge (P<0.01 vs all other groups) and show depressive-like behavior during a forced swim test. Furthermore, expression of neuropeptide Y within the amygdala, known for anxiolytic properties following chronic stress, was elevated among OMEGA (group×region interaction P<0.001). Together these observations suggest that an additional phenotype exists among the SUB animals within a VBS colony and represents the variability of the effects of chronic social stress.
Collapse
Affiliation(s)
- Susan J Melhorn
- Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH, United States.
| | - Clinton T Elfers
- Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Karen A Scott
- Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Randall R Sakai
- Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| |
Collapse
|
40
|
Kornhuber J, Zoicas I. Neuropeptide Y prolongs non-social memory and differentially affects acquisition, consolidation, and retrieval of non-social and social memory in male mice. Sci Rep 2017; 7:6821. [PMID: 28754895 PMCID: PMC5533709 DOI: 10.1038/s41598-017-07273-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 06/23/2017] [Indexed: 01/08/2023] Open
Abstract
Neuropeptide Y (NPY) and its receptors (especially Y1, Y2, and Y5) are highly expressed in brain regions involved in learning and memory processes. Accordingly, NPY was shown to modulate cognitive functions in rodents. Here, we investigated possible memory-enhancing effects of NPY and determined the role of the NPY system in the acquisition, consolidation, and retrieval of non-social and social memory in mice, using the object and social discrimination tests, respectively. Intracerebroventricular (icv) infusion of NPY (1 nmol/2 µl) prolonged retention of non-social (object) memory, but not of social memory. This effect was blocked by the Y1 receptor antagonist BIBO3304 trifluoroacetate (2 nmol/2 µl), but not by the Y2 receptor antagonist BIIE0246 (2 nmol/2 µl). While icv infusion of NPY did not affect the acquisition, consolidation, and retrieval of non-social and social memory, icv infusion of BIBO3304 trifluoroacetate and BIIE0246 blocked the consolidation of non-social memory and the retrieval of both non-social and social memory. This study suggests that NPY has memory-enhancing effects in a non-social context by specifically acting on Y1 receptors. It further suggests that the central NPY system exerts differential effects on the sequential phases of non-social and social memory.
Collapse
Affiliation(s)
- Johannes Kornhuber
- Department of Psychiatry and Psychotherapy, University Hospital, Friedrich-Alexander-University Erlangen-Nuremberg, 91054, Erlangen, Germany
| | - Iulia Zoicas
- Department of Psychiatry and Psychotherapy, University Hospital, Friedrich-Alexander-University Erlangen-Nuremberg, 91054, Erlangen, Germany.
| |
Collapse
|
41
|
Rasmusson AM, Marx CE, Pineles SL, Locci A, Scioli-Salter ER, Nillni YI, Liang JJ, Pinna G. Neuroactive steroids and PTSD treatment. Neurosci Lett 2017; 649:156-163. [PMID: 28215878 DOI: 10.1016/j.neulet.2017.01.054] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 01/22/2017] [Accepted: 01/23/2017] [Indexed: 01/08/2023]
Abstract
This review highlights early efforts to translate pre-clinical and clinical findings regarding the role of neuroactive steroids in stress adaptation and PTSD into new therapeutics for PTSD. Numerous studies have demonstrated PTSD-related alterations in resting levels or the reactivity of neuroactive steroids and their targets. These studies also have demonstrated substantial variability in the dysfunction of specific neuroactive steroid systems among PTSD subpopulations. These variabilities have been related to the developmental timing of trauma, severity and type of trauma, genetic background, sex, reproductive state, lifestyle influences such as substance use and exercise, and the presence of comorbid conditions such as depression and chronic pain. Nevertheless, large naturalistic studies and a small placebo-controlled interventional study have revealed generally positive effects of glucocorticoid administration in preventing PTSD after trauma, possibly mediated by glucocorticoid receptor-mediated effects on other targets that impact PTSD risk, including other neuroactive steroid systems. In addition, clinical and preclinical studies show that administration of glucocorticoids, 17β-estradiol, and GABAergic neuroactive steroids or agents that enhance their synthesis can facilitate extinction and extinction retention, depending on dose and timing of dose in relation to these complex PTSD-relevant recovery processes. This suggests that clinical trials designed to test neuroactive steroid therapeutics in PTSD may benefit from such considerations; typical continuous dosing regimens may not be optimal. In addition, validated and clinically accessible methods for identifying specific neuroactive steroid system abnormalities at the individual level are needed to optimize both clinical trial design and precision medicine based treatment targeting.
Collapse
Affiliation(s)
- Ann M Rasmusson
- National Center for PTSD, Women's Health Science Division, Department of Veterans Affairs 150 South Huntington Avenue, Boston, MA 02135, USA; VA Boston Healthcare System 150 South Huntington Avenue, Boston, MA 02135, USA; Boston University School of Medicine 72 E Concord St, Boston, MA 02118, USA.
| | - Christine E Marx
- Durham VA Medical Center, VA Mid-Atlantic MIRECC,and Duke University Medical Center, 508 Fulton Street, Durham, NC 27705, USA
| | - Suzanne L Pineles
- National Center for PTSD, Women's Health Science Division, Department of Veterans Affairs 150 South Huntington Avenue, Boston, MA 02135, USA; Boston University School of Medicine 72 E Concord St, Boston, MA 02118, USA
| | - Andrea Locci
- The Psychiatric Institute, Department of Psychiatry, University of Illinois at Chicago, 1601 W. Taylor Str., Chicago, IL 60612, USA
| | - Erica R Scioli-Salter
- VA Boston Healthcare System 150 South Huntington Avenue, Boston, MA 02135, USA; Boston University School of Medicine 72 E Concord St, Boston, MA 02118, USA
| | - Yael I Nillni
- National Center for PTSD, Women's Health Science Division, Department of Veterans Affairs 150 South Huntington Avenue, Boston, MA 02135, USA; Boston University School of Medicine 72 E Concord St, Boston, MA 02118, USA
| | - Jennifer J Liang
- Boston University School of Medicine 72 E Concord St, Boston, MA 02118, USA
| | - Graziano Pinna
- The Psychiatric Institute, Department of Psychiatry, University of Illinois at Chicago, 1601 W. Taylor Str., Chicago, IL 60612, USA
| |
Collapse
|
42
|
Michopoulos V, Vester A, Neigh G. Posttraumatic stress disorder: A metabolic disorder in disguise? Exp Neurol 2016; 284:220-229. [PMID: 27246996 PMCID: PMC5056806 DOI: 10.1016/j.expneurol.2016.05.038] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 05/24/2016] [Accepted: 05/26/2016] [Indexed: 12/30/2022]
Abstract
Posttraumatic stress disorder (PTSD) is a heterogeneous psychiatric disorder that affects individuals exposed to trauma and is highly co-morbid with other adverse health outcomes, including cardiovascular disease and obesity. The unique pathophysiological feature of PTSD is the inability to inhibit fear responses, such that individuals suffering from PTSD re-experience traumatic memories and are unable to control psychophysiological responses to trauma-associated stimuli. However, underlying alterations in sympathetic nervous system activity, neuroendocrine systems, and metabolism associated with PTSD are similar to those present in traditional metabolic disorders, such as obesity and diabetes. The current review highlights existing clinical, translational, and preclinical data that support the notion that underneath the primary indication of impaired fear inhibition, PTSD is itself also a metabolic disorder and proposes altered function of inflammatory responses as a common underlying mechanism. The therapeutic implications of treating PTSD as a whole-body condition are significant, as targeting any underlying biological system whose activity is altered in both PTSD and metabolic disorders, (i.e. HPA axis, sympathetic nervous systems, inflammation) may elicit symptomatic relief in individuals suffering from these whole-body adverse outcomes.
Collapse
Affiliation(s)
- Vasiliki Michopoulos
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, United States; Yerkes National Primate Research Center, Atlanta, GA, United States
| | - Aimee Vester
- Department of Environmental Health Sciences, Rollins School of Public Health, Atlanta, GA, United States
| | - Gretchen Neigh
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, United States; Yerkes National Primate Research Center, Atlanta, GA, United States; Department of Physiology, Emory University School of Medicine, Atlanta, GA, United States.
| |
Collapse
|
43
|
Schmeltzer SN, Herman JP, Sah R. Neuropeptide Y (NPY) and posttraumatic stress disorder (PTSD): A translational update. Exp Neurol 2016; 284:196-210. [PMID: 27377319 PMCID: PMC8375392 DOI: 10.1016/j.expneurol.2016.06.020] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 06/15/2016] [Accepted: 06/20/2016] [Indexed: 12/12/2022]
Abstract
Posttraumatic stress disorder (PTSD) is a trauma-evoked syndrome, with variable prevalence within the human population due to individual differences in coping and resiliency. In this review, we discuss evidence supporting the relevance of neuropeptide Y (NPY), a stress regulatory transmitter in PTSD. We consolidate findings from preclinical, clinical, and translational studies of NPY that are of relevance to PTSD with an attempt to provide a current update of this area of research. NPY is abundantly expressed in forebrain limbic and brainstem areas that regulate stress and emotional behaviors. Studies in rodents demonstrate a role for NPY in stress responses, anxiety, fear, and autonomic regulation, all relevant to PTSD symptomology. Genetic studies support an association of NPY polymorphisms with stress coping and affect. Importantly, cerebrospinal fluid (CSF) measurements in combat veterans provide direct evidence of NPY association with PTSD diagnosis and symptomology. In addition, NPY involvement in pain, depression, addiction, and metabolism may be relevant to comorbidities associated with PTSD. Collectively, the literature supports the relevance of NPY to PTSD pathophysiology, although knowledge gaps remain. The NPY system is an attractive target in terms of understanding the physiological basis of PTSD as well as treatment of the disorder.
Collapse
Affiliation(s)
- Sarah N Schmeltzer
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH 45237, United States
| | - James P Herman
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH 45237, United States
| | - Renu Sah
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH 45237, United States; VA Medical Center, Cincinnati, OH, 45220, United States.
| |
Collapse
|
44
|
Verma D, Hörmer B, Bellmann-Sickert K, Thieme V, Beck-Sickinger AG, Herzog H, Sperk G, Tasan RO. Pancreatic polypeptide and its central Y4 receptors are essential for cued fear extinction and permanent suppression of fear. Br J Pharmacol 2016; 173:1925-38. [PMID: 26844810 PMCID: PMC4882497 DOI: 10.1111/bph.13456] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 01/26/2016] [Accepted: 01/29/2016] [Indexed: 12/18/2022] Open
Abstract
Background and purpose Avoiding danger and finding food are closely related behaviours that are essential for surviving in a natural environment. Growing evidence supports an important role of gut‐brain peptides in modulating energy homeostasis and emotional‐affective behaviour. For instance, postprandial release of pancreatic polypeptide (PP) reduced food intake and altered stress‐induced motor activity and anxiety by activating central Y4 receptors. Experimental approach We characterized [K30(PEG2)]hPP2‐36 as long‐acting Y4 receptor agonist and injected it peripherally into wildtype and Y4 receptor knockout (Y4KO) C57Bl/6NCrl mice to investigate the role of Y4 receptors in fear conditioning. Extinction and relapse after extinction was measured by spontaneous recovery and renewal. Key results The Y4KO mice showed impaired cued and context fear extinction without affecting acquisition, consolidation or recall of fear. Correspondingly, peripheral injection of [K30(PEG2)]hPP2‐36 facilitated extinction learning upon fasting, an effect that was long‐lasting and generalized. Furthermore, peripherally applied [K30(PEG2)]hPP2‐36 before extinction inhibited the activation of orexin‐expressing neurons in the lateral hypothalamus in WT, but not in Y4KO mice. Conclusions and implications Our findings suggests suppression of excessive arousal as a possible mechanism for the extinction‐promoting effect of central Y4 receptors and provide strong evidence that fear extinction requires integration of vegetative stimuli with cortical and subcortical information, a process crucially depending on Y4 receptors. Importantly, in the lateral hypothalamus two peptide systems, PP and orexin, interact to generate an emotional response adapted to the current homeostatic state. Detailed investigations of feeding‐relevant genes may thus deliver multiple intervention points for treating anxiety‐related disorders.
Collapse
Affiliation(s)
- D Verma
- Department of Pharmacology, Medical University Innsbruck, Innsbruck, Austria
| | - B Hörmer
- Department of Pharmacology, Medical University Innsbruck, Innsbruck, Austria
| | | | - V Thieme
- Institute of Biochemistry, Leipzig University, Leipzig, Germany
| | | | - H Herzog
- Neuroscience Research Program, Garvan Institute of Medical Research, Sydney, Australia
| | - G Sperk
- Department of Pharmacology, Medical University Innsbruck, Innsbruck, Austria
| | - R O Tasan
- Department of Pharmacology, Medical University Innsbruck, Innsbruck, Austria
| |
Collapse
|
45
|
Sabban EL, Alaluf LG, Serova LI. Potential of neuropeptide Y for preventing or treating post-traumatic stress disorder. Neuropeptides 2016; 56:19-24. [PMID: 26617395 DOI: 10.1016/j.npep.2015.11.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 11/11/2015] [Accepted: 11/11/2015] [Indexed: 10/22/2022]
Abstract
There is extensive evidence that NPY in the brain can modulate the responses to stress and play a critical role in resistance to, or recovery from, harmful effects of stress. Development of PTSD and comorbid depression following exposure to traumatic stress are associated with low NPY. This review discusses putative mechanisms for NPY's anti-stress actions. Recent preclinical data indicating potential for intranasal delivery of NPY to brain as a promising non-invasive strategy to prevent a variety of neuroendocrine, molecular and behavioral impairments in PTSD model are summarized.
Collapse
Affiliation(s)
- Esther L Sabban
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, United States.
| | - Lishay G Alaluf
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, United States
| | - Lidia I Serova
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, United States
| |
Collapse
|
46
|
Hoffman KL. New dimensions in the use of rodent behavioral tests for novel drug discovery and development. Expert Opin Drug Discov 2016; 11:343-53. [DOI: 10.1517/17460441.2016.1153624] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
47
|
Leitermann RJ, Rostkowski AB, Urban JH. Neuropeptide Y input to the rat basolateral amygdala complex and modulation by conditioned fear. J Comp Neurol 2016; 524:2418-39. [PMID: 26779765 DOI: 10.1002/cne.23960] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 12/30/2015] [Accepted: 01/05/2016] [Indexed: 12/14/2022]
Abstract
Within the basolateral amygdaloid complex (BLA), neuropeptide Y (NPY) buffers against protracted anxiety and fear. Although the importance of NPY's actions in the BLA is well documented, little is known about the source(s) of NPY fibers to this region. The current studies identified sources of NPY projections to the BLA by using a combination of anatomical and neurochemical approaches. NPY innervation of the BLA was assessed in rats by examining the degree of NPY coexpression within interneurons or catecholaminergic fibers with somatostatin and tyrosine hydroxylase (TH) or dopamine β-hydroxylase (DβH), respectively. Numerous NPY(+) /somatostatin(+) and NPY(+) /somatostatin(-) fibers were observed, suggesting at least two populations of NPY fibers within the BLA. No colocalization was noted between NPY and TH or DβH immunoreactivities. Additionally, Fluorogold (FG) retrograde tracing with immunohistochemistry was used to identify the precise origin of NPY projections to the BLA. FG(+) /NPY(+) cells were identified within the amygdalostriatal transition area (AStr) and stria terminalis and scattered throughout the bed nucleus of the stria terminalis. The subpopulation of NPY neurons in the AStr also coexpressed somatostatin. Subjecting animals to a conditioned fear paradigm increased NPY gene expression within the AStr, whereas no changes were observed within the BLA or stria terminalis. Overall, these studies identified limbic regions associated with stress circuits providing NPY input to the BLA and demonstrated that a unique NPY projection from the AStr may participate in the regulation of conditioned fear. J. Comp. Neurol. 524:2418-2439, 2016. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Randy J Leitermann
- Department of Physiology and Biophysics, The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois
| | - Amanda B Rostkowski
- Department of Physiology and Biophysics, The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois
| | - Janice H Urban
- Department of Physiology and Biophysics, The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois
| |
Collapse
|
48
|
Lach G, Bicca MA, Hoeller AA, Santos ECDS, Costa APR, de Lima TCM. Short-term enriched environment exposure facilitates fear extinction in adult rats: The NPY-Y1 receptor modulation. Neuropeptides 2016; 55:73-8. [PMID: 26490304 DOI: 10.1016/j.npep.2015.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 09/30/2015] [Accepted: 10/01/2015] [Indexed: 12/14/2022]
Abstract
Neuropeptides have an important role in several psychiatric conditions. Among them, neuropeptide Y (NPY) seems to be essential to modulate some features of stress-related disorders. Post-traumatic stress disorder (PTSD), characterized by inappropriate fear generalization to safe situations may be modulated by NPY manipulation since this neuropeptide is involved in the promotion of coping with stress. Experimentally, coping strategies have been obtained after exposure in enriched environment (EE) rather than standard one. Thus, in the present study we aimed to assess whether short-term EE situation and NPY-Y1 receptor (Y1r) modulation may affect the extinction of contextual fear conditioning, an experimental approach to PTSD. Here we show that EE-rats have the contextual fear extinction facilitated, and this facilitation was reverted by central infusion of BIBO3304, a nonpeptide Y1r antagonist. In addition, protein analysis revealed an upregulation of hippocampal Y1r in conditioned EE-rats, but no changes were observed in EE-rats that were not conditioned. Our results demonstrated that protective properties of EE on fear extinction can be regulated, at least in part, by activation of NPY-signaling through Y1r within hippocampus, an area that plays a major role in contextual memories. Overall, the activation of Y1r is important to promote better and faster perception of self-location (context), and to reduce fear generalization in rats exposed to EE.
Collapse
Affiliation(s)
- Gilliard Lach
- Department of Pharmacology, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, SC 88049-900, Brazil.
| | - Maira Assunção Bicca
- Department of Pharmacology, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, SC 88049-900, Brazil
| | - Alexandre Ademar Hoeller
- Department of Pharmacology, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, SC 88049-900, Brazil; Postgraduate Program in Medical Science, Center of Health Sciences, University Hospital, Federal University of Santa Catarina, Florianópolis, SC 88040-970, Brazil
| | - Evelyn Cristina da Silva Santos
- Department of Pharmacology, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, SC 88049-900, Brazil
| | - Ana Paula Ramos Costa
- Department of Pharmacology, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, SC 88049-900, Brazil
| | | |
Collapse
|
49
|
Tasan RO, Verma D, Wood J, Lach G, Hörmer B, de Lima TCM, Herzog H, Sperk G. The role of Neuropeptide Y in fear conditioning and extinction. Neuropeptides 2016; 55:111-26. [PMID: 26444585 DOI: 10.1016/j.npep.2015.09.007] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 09/10/2015] [Accepted: 09/10/2015] [Indexed: 12/23/2022]
Abstract
While anxiety disorders are the brain disorders with the highest prevalence and constitute a major burden for society, a considerable number of affected people are still treated insufficiently. Thus, in an attempt to identify potential new anxiolytic drug targets, neuropeptides have gained considerable attention in recent years. Compared to classical neurotransmitters they often have a regionally restricted distribution and may bind to several distinct receptor subtypes. Neuropeptide Y (NPY) is a highly conserved neuropeptide that is specifically concentrated in limbic brain areas and signals via at least 5 different G-protein-coupled receptors. It is involved in a variety of physiological processes including the modulation of emotional-affective behaviors. An anxiolytic and stress-reducing property of NPY is supported by many preclinical studies. Whether NPY may also interact with processing of learned fear and fear extinction is comparatively unknown. However, this has considerable relevance since pathological, inappropriate and generalized fear expression and impaired fear extinction are hallmarks of human post-traumatic stress disorder and a major reason for its treatment-resistance. Recent evidence from different laboratories emphasizes a fear-reducing role of NPY, predominantly mediated by exogenous NPY acting on Y1 receptors. Since a reduction of fear expression was also observed in Y1 receptor knockout mice, other Y receptors may be equally important. By acting on Y2 receptors, NPY promotes fear extinction and generates a long-term suppression of fear, two important preconditions that could support cognitive behavioral therapies in human patients. A similar effect has been demonstrated for the closely related pancreatic polypeptide (PP) when acting on Y4 receptors. Preliminary evidence suggests that NPY modulates fear in particular by activation of Y1 and Y2 receptors in the basolateral and central amygdala, respectively. In the basolateral amygdala, NPY signaling activates inhibitory G protein-coupled inwardly-rectifying potassium channels or suppresses hyperpolarization-induced I(h) currents in a Y1 receptor-dependent fashion, favoring a general suppression of neuronal activity. A more complex situation has been described for the central extended amygdala, where NPY reduces the frequency of inhibitory and excitatory postsynaptic currents. In particular the inhibition of long-range central amygdala output neurons may result in a Y2 receptor-dependent suppression of fear. The role of NPY in processes of learned fear and fear extinction is, however, only beginning to emerge, and multiple questions regarding the relevance of endogenous NPY and different receptor subtypes remain elusive. Y2 receptors may be of particular interest for future studies, since they are the most prominent Y receptor subtype in the human brain and thus among the most promising therapeutic drug targets when translating preclinical evidence to potential new therapies for human anxiety disorders.
Collapse
Affiliation(s)
- R O Tasan
- Department of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria.
| | - D Verma
- Institute of Physiology I, University of Münster, D-48149 Münster, Germany
| | - J Wood
- Department of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - G Lach
- Department of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria; Capes Foundation, Ministry of Education of Brazil, 70040-020 Brasília/DF, Brazil
| | - B Hörmer
- Department of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - T C M de Lima
- Department of Pharmacology, Federal University of Santa Catarina, 88049-970 Florianópolis, Brazil
| | - H Herzog
- Neuroscience Research Program, Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW 2010, Australia
| | - G Sperk
- Department of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria
| |
Collapse
|
50
|
Gøtzsche CR, Woldbye DPD. The role of NPY in learning and memory. Neuropeptides 2016; 55:79-89. [PMID: 26454711 DOI: 10.1016/j.npep.2015.09.010] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 09/29/2015] [Accepted: 09/29/2015] [Indexed: 01/07/2023]
Abstract
High levels of NPY expression in brain regions important for learning and memory together with its neuromodulatory and neurotrophic effects suggest a regulatory role for NPY in memory processes. Therefore it is not surprising that an increasing number of studies have provided evidence for NPY acting as a modulator of neuroplasticity, neurotransmission, and memory. Here these results are presented in relation to the types of memory affected by NPY and its receptors. NPY can exert both inhibitory and stimulatory effects on memory, depending on memory type and phase, dose applied, brain region, and NPY receptor subtypes. Thus NPY act as a resilience factor by impairing associative implicit memory after stressful and aversive events, as evident in models of fear conditioning, presumably via Y1 receptors in the amygdala and prefrontal cortex. In addition, NPY impairs acquisition but enhances consolidation and retention in models depending on spatial and discriminative types of associative explicit memory, presumably involving Y2 receptor-mediated regulations of hippocampal excitatory transmission. Moreover, spatial memory training leads to increased hippocampal NPY gene expression that together with Y1 receptor-mediated neurogenesis could constitute necessary steps in consolidation and long-term retention of spatial memory. Altogether, NPY-induced effects on learning and memory seem to be biphasic, anatomically and temporally differential, and in support of a modulatory role of NPY at keeping the system in balance. Obtaining further insight into memory-related effects of NPY could inspire the engineering of new therapeutics targeting diseases where impaired learning and memory are central elements.
Collapse
Affiliation(s)
- C R Gøtzsche
- Laboratory of Neural Plasticity, Department of Neuroscience and Pharmacology, University of Copenhagen, Denmark.
| | - D P D Woldbye
- Laboratory of Neural Plasticity, Department of Neuroscience and Pharmacology, University of Copenhagen, Denmark
| |
Collapse
|