1
|
Michelson NJ, Vazquez AL, Eles JR, Salatino JW, Purcell EK, Williams JJ, Cui XT, Kozai TDY. Multi-scale, multi-modal analysis uncovers complex relationship at the brain tissue-implant neural interface: new emphasis on the biological interface. J Neural Eng 2018; 15:033001. [PMID: 29182149 PMCID: PMC5967409 DOI: 10.1088/1741-2552/aa9dae] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Implantable neural electrode devices are important tools for neuroscience research and have an increasing range of clinical applications. However, the intricacies of the biological response after implantation, and their ultimate impact on recording performance, remain challenging to elucidate. Establishing a relationship between the neurobiology and chronic recording performance is confounded by technical challenges related to traditional electrophysiological, material, and histological limitations. This can greatly impact the interpretations of results pertaining to device performance and tissue health surrounding the implant. APPROACH In this work, electrophysiological activity and immunohistological analysis are compared after controlling for motion artifacts, quiescent neuronal activity, and material failure of devices in order to better understand the relationship between histology and electrophysiological outcomes. MAIN RESULTS Even after carefully accounting for these factors, the presence of viable neurons and lack of glial scarring does not convey single unit recording performance. SIGNIFICANCE To better understand the biological factors influencing neural activity, detailed cellular and molecular tissue responses were examined. Decreases in neural activity and blood oxygenation in the tissue surrounding the implant, shift in expression levels of vesicular transporter proteins and ion channels, axon and myelin injury, and interrupted blood flow in nearby capillaries can impact neural activity around implanted neural interfaces. Combined, these tissue changes highlight the need for more comprehensive, basic science research to elucidate the relationship between biology and chronic electrophysiology performance in order to advance neural technologies.
Collapse
Affiliation(s)
| | - Alberto L Vazquez
- Department of Bioengineering, University of Pittsburgh
- Department of Radiology, University of Pittsburgh
- Center for the Neural Basis of Cognition, University of Pittsburgh
- Center for Neuroscience, University of Pittsburgh
| | - James R Eles
- Department of Bioengineering, University of Pittsburgh
- Center for the Neural Basis of Cognition, University of Pittsburgh
| | | | - Erin K Purcell
- Department of Biomedical Engineering, Michigan State University
| | | | - X. Tracy Cui
- Department of Bioengineering, University of Pittsburgh
- Center for the Neural Basis of Cognition, University of Pittsburgh
- McGowan Institute of Regenerative Medicine, University of Pittsburgh
| | - Takashi DY Kozai
- Department of Bioengineering, University of Pittsburgh
- Center for the Neural Basis of Cognition, University of Pittsburgh
- Center for Neuroscience, University of Pittsburgh
- McGowan Institute of Regenerative Medicine, University of Pittsburgh
- NeuroTech Center, University of Pittsburgh Brain Institute
| |
Collapse
|
2
|
Jochems J, Boulden J, Lee BG, Blendy JA, Jarpe M, Mazitschek R, Van Duzer JH, Jones S, Berton O. Antidepressant-like properties of novel HDAC6-selective inhibitors with improved brain bioavailability. Neuropsychopharmacology 2014; 39:389-400. [PMID: 23954848 DOI: 10.1038/npp.2013.207] [Citation(s) in RCA: 122] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Revised: 07/15/2013] [Accepted: 08/02/2013] [Indexed: 12/13/2022]
Abstract
HDAC inhibitors have been reported to produce antidepressant and pro-cognitive effects in animal models, however, poor brain bioavailability or lack of isoform selectivity of current probes has limited our understanding of their mode of action. We report the characterization of novel pyrimidine hydroxyl amide small molecule inhibitors of HDAC6, brain bioavailable upon systemic administration. We show that two compounds in this family, ACY-738 and ACY-775, inhibit HDAC6 with low nanomolar potency and a selectivity of 60- to 1500-fold over class I HDACs. In contrast to tubastatin A, a reference HDAC6 inhibitor with similar potency and peripheral activity, but more limited brain bioavailability, ACY-738 and ACY-775 induce dramatic increases in α-tubulin acetylation in brain and stimulate mouse exploratory behaviors in novel, but not familiar environments. Interestingly, despite a lack of detectable effect on histone acetylation, we show that ACY-738 and ACY-775 share the antidepressant-like properties of other HDAC inhibitors, such as SAHA and MS-275, in the tail suspension test and social defeat paradigm. These effects of ACY-738 and ACY-775 are directly attributable to the inhibition of HDAC6 expressed centrally, as they are fully abrogated in mice with a neural-specific loss of function of HDAC6. Furthermore, administered in combination, a behaviorally inactive dose of ACY-738 markedly potentiates the anti-immobility activity of a subactive dose of the selective serotonin reuptake inhibitor citalopram. Our results validate new isoform-selective probes for in vivo pharmacological studies of HDAC6 in the CNS and reinforce the viability of this HDAC isoform as a potential target for antidepressant development.
Collapse
|
3
|
Tam RY, Fuehrmann T, Mitrousis N, Shoichet MS. Regenerative therapies for central nervous system diseases: a biomaterials approach. Neuropsychopharmacology 2014; 39:169-88. [PMID: 24002187 PMCID: PMC3857664 DOI: 10.1038/npp.2013.237] [Citation(s) in RCA: 172] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 07/09/2013] [Accepted: 07/12/2013] [Indexed: 02/07/2023]
Abstract
The central nervous system (CNS) has a limited capacity to spontaneously regenerate following traumatic injury or disease, requiring innovative strategies to promote tissue and functional repair. Tissue regeneration strategies, such as cell and/or drug delivery, have demonstrated promising results in experimental animal models, but have been difficult to translate clinically. The efficacy of cell therapy, which involves stem cell transplantation into the CNS to replace damaged tissue, has been limited due to low cell survival and integration upon transplantation, while delivery of therapeutic molecules to the CNS using conventional methods, such as oral and intravenous administration, have been limited by diffusion across the blood-brain/spinal cord-barrier. The use of biomaterials to promote graft survival and integration as well as localized and sustained delivery of biologics to CNS injury sites is actively being pursued. This review will highlight recent advances using biomaterials as cell- and drug-delivery vehicles for CNS repair.
Collapse
Affiliation(s)
- Roger Y Tam
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Donnelly Centre for Cellular and Biomolecular Research, Toronto, ON, Canada,Institute of Biomaterials and Biomedical Engineering, Toronto, ON, Canada
| | - Tobias Fuehrmann
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Donnelly Centre for Cellular and Biomolecular Research, Toronto, ON, Canada,Institute of Biomaterials and Biomedical Engineering, Toronto, ON, Canada
| | - Nikolaos Mitrousis
- Institute of Biomaterials and Biomedical Engineering, Toronto, ON, Canada
| | - Molly S Shoichet
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Donnelly Centre for Cellular and Biomolecular Research, Toronto, ON, Canada,Institute of Biomaterials and Biomedical Engineering, Toronto, ON, Canada,Department of Chemistry, University of Toronto, Toronto, ON, Canada,Department of Chemical Engineering and Applied Chemistry, University of Toronto, Donnelly Centre for Cellular and Biomolecular Research, 160 College Street, Room 514, Toronto, ON, Canada, Tel: +416 978 1460, Fax: +416 978 4317, E-mail:
| |
Collapse
|
4
|
Abstract
Methyl-CpG-binding protein 2 (MeCP2) is a transcriptional regulator of gene expression that is an important epigenetic factor in the maintenance and development of the central nervous system. The neurodevelopmental disorders Rett syndrome and MECP2 duplication syndrome arise from loss-of-function and gain-of-function alterations in MeCP2 expression, respectively. Several animal models have been developed to recapitulate the symptoms of Rett syndrome and MECP2 duplication syndrome. Cell morphology, neurotransmission, and cellular processes that support learning and memory are compromised as a result of MeCP2 loss- or gain-of-function. Interestingly, loss-of-MeCP2 function and MeCP2 overexpression trigger diametrically opposite changes in synaptic transmission. These findings indicate that the precise regulation of MeCP2 expression is a key requirement for the maintenance of synaptic and neuronal homeostasis and underscore its importance in central nervous system function. This review highlights the functional role of MeCP2 in the brain as a regulator of synaptic and neuronal plasticity as well as its etiological role in the development of Rett syndrome and MECP2 duplication syndrome.
Collapse
Affiliation(s)
- Elisa S Na
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Erika D Nelson
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ege T Kavalali
- Department of Neuroscience, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Lisa M Monteggia
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, USA,Department of Psychiatry, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9070, USA, Tel: +1 214 648 5548, Fax: +1 214 648 4947, E-mail:
| |
Collapse
|
5
|
Abstract
The rewarding properties of opioids are essential driving force for compulsive drug-seeking and drug-taking behaviors in the development of opioid-mediated drug addiction. Prior drug use enhances sensitivity to the rewarding effects of subsequently used drugs, increasing vulnerability to relapse. The molecular mechanisms underlying this reward sensitization are still unclear. We report here that morphine that induced reward sensitization, as demonstrated by reinstatement of the behavior of conditioned place preference (CPP) with sub-threshold priming morphine, epigenetically upregulated the output activity of Ngf encoding the nerve growth factor (NGF) by increasing histone H4 acetylation in the rat central nucleus of the amygdala (CeA). NGF locally infused into the CeA mimicked the morphine effect in inducing new functional delta-opioid receptor (DOR) that was required for the reward sensitization, and morphine-induced reward sensitization was inhibited by blocking NGF receptor signaling in the CeA. Histone deacetylase inhibitors that increased the acetylation level at the Ngf promoter and NGF expression in the CeA also induced reward sensitization in a CeA NGF signaling- and DOR-dependent manner. Furthermore, CeA-applied NGF substituted prior morphine to induce reward sensitization in naive rats and also substituted priming morphine to reinstate the CPP induced by prior morphine. Thus, epigenetic upregulation of NGF activity in the CeA may promote the behavior of opioid reward and increase the sensitivity to the rewarding effect of subsequent opioids, a potentially important mechanism in drug addiction.
Collapse
Affiliation(s)
- Bihua Bie
- Department of Anesthesiology and Pain Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Yan Wang
- Department of Anesthesiology and Pain Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - You-Qing Cai
- Department of Anesthesiology and Pain Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Zhi Zhang
- Department of Anesthesiology and Pain Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Yuan-Yuan Hou
- Department of Anesthesiology and Pain Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Zhizhong Z Pan
- Department of Anesthesiology and Pain Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA,Department of Anesthesiology and Pain Medicine, Unit 110, The University of Texas-MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA, Tel: +1 713 792 5559, Fax: +1 713 745 3040, E-mail:
| |
Collapse
|
6
|
Bermingham R, Carballedo A, Lisiecka D, Fagan A, Morris D, Fahey C, Donohoe G, Meaney J, Gill M, Frodl T. Effect of genetic variant in BICC1 on functional and structural brain changes in depression. Neuropsychopharmacology 2012; 37:2855-62. [PMID: 22910460 PMCID: PMC3499713 DOI: 10.1038/npp.2012.158] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Genes and early-life adversity (ELA) interactively increase the risk of developing major depressive disorder (MDD). A recent genome-wide association study suggests that the minor T-allele of single-nucleotide polymorphisms in the bicaudal C homolog 1 gene (BICC1) has a protective role against MDD. The aims of the study were to investigate whether the minor T-allele of BICC1 is protective against hippocampal structural brain changes, whether it is associated with increased functional brain activity in the emotion regulation system, and how ELA would modify this association. Forty-four patients with MDD and 44 healthy controls were investigated using structural magnetic resonance imaging (MRI) and functional MRI with an emotion inhibition task. Analysis of a single-nucleotide polymorphism in the BICC1-1 (rs999845) gene was performed. Right hippocampal bodies of patients and controls without a history of ELA and who carry the protective T-allele of BICC1 were significantly larger compared with those participants homozygous for the major C-allele of BICC1. However, MDD patients with ELA, who carry the T-allele, had smaller hippocampal head volumes compared with MDD patients without ELA. FMRI showed that patients and controls carrying the protective T-allele of BICC1 activate the emotion regulation system significantly more compared with those participants homozygous for the major C-allele (p<0.05, family wise error corrected). These results are suggestive that the minor T-allele of BICC1 has a protective role against MDD and its known structural and functional brain changes. However, this protective effect seems to be lost in the case of co-occurrence of ELA.
Collapse
Affiliation(s)
- Rachel Bermingham
- Integrated Neuroimaging Group, Department of Psychiatry and Institute of Neuroscience, School of Medicine, Trinity College Dublin, University of Dublin, College Green, Dublin, Ireland
| | - Angela Carballedo
- Integrated Neuroimaging Group, Department of Psychiatry and Institute of Neuroscience, School of Medicine, Trinity College Dublin, University of Dublin, College Green, Dublin, Ireland,Centre of Advanced Medical Imaging, St James's Hospital, Trinity College Dublin, Dublin, Ireland
| | - Danuta Lisiecka
- Integrated Neuroimaging Group, Department of Psychiatry and Institute of Neuroscience, School of Medicine, Trinity College Dublin, University of Dublin, College Green, Dublin, Ireland
| | - Andrew Fagan
- Centre of Advanced Medical Imaging, St James's Hospital, Trinity College Dublin, Dublin, Ireland
| | - Derek Morris
- Neuropsychiatric Genetics Group, Department of Psychiatry and Institute of Neuroscience, School of Medicine, Trinity College Dublin, University of Dublin, College Green, Dublin, Ireland
| | - Ciara Fahey
- Neuropsychiatric Genetics Group, Department of Psychiatry and Institute of Neuroscience, School of Medicine, Trinity College Dublin, University of Dublin, College Green, Dublin, Ireland
| | - Gary Donohoe
- Neuropsychiatric Genetics Group, Department of Psychiatry and Institute of Neuroscience, School of Medicine, Trinity College Dublin, University of Dublin, College Green, Dublin, Ireland
| | - James Meaney
- Centre of Advanced Medical Imaging, St James's Hospital, Trinity College Dublin, Dublin, Ireland
| | - Michael Gill
- Neuropsychiatric Genetics Group, Department of Psychiatry and Institute of Neuroscience, School of Medicine, Trinity College Dublin, University of Dublin, College Green, Dublin, Ireland
| | - Thomas Frodl
- Integrated Neuroimaging Group, Department of Psychiatry and Institute of Neuroscience, School of Medicine, Trinity College Dublin, University of Dublin, College Green, Dublin, Ireland,Centre of Advanced Medical Imaging, St James's Hospital, Trinity College Dublin, Dublin, Ireland,Neuropsychiatric Genetics Group, Department of Psychiatry and Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland, Tel: +353 18963397, Fax: +353 18961313, E-mail:
| |
Collapse
|
7
|
Ionescu IA, Dine J, Yen YC, Buell DR, Herrmann L, Holsboer F, Eder M, Landgraf R, Schmidt U. Intranasally administered neuropeptide S (NPS) exerts anxiolytic effects following internalization into NPS receptor-expressing neurons. Neuropsychopharmacology 2012; 37:1323-37. [PMID: 22278093 DOI: 10.1038/npp.2011.317] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Experiments in rodents revealed neuropeptide S (NPS) to constitute a potential novel treatment option for anxiety diseases such as panic and post-traumatic stress disorder. However, both its cerebral target sites and the molecular underpinnings of NPS-mediated effects still remain elusive. By administration of fluorophore-conjugated NPS, we pinpointed NPS target neurons in distinct regions throughout the entire brain. We demonstrated their functional relevance in the hippocampus. In the CA1 region, NPS modulates synaptic transmission and plasticity. NPS is taken up into NPS receptor-expressing neurons by internalization of the receptor-ligand complex as we confirmed by subsequent cell culture studies. Furthermore, we tracked internalization of intranasally applied NPS at the single-neuron level and additionally demonstrate that it is delivered into the mouse brain without losing its anxiolytic properties. Finally, we show that NPS differentially modulates the expression of proteins of the glutamatergic system involved inter alia in synaptic plasticity. These results not only enlighten the path of NPS in the brain, but also establish a non-invasive method for NPS administration in mice, thus strongly encouraging translation into a novel therapeutic approach for pathological anxiety in humans.
Collapse
|
8
|
Gavin DP, Sharma RP, Chase KA, Matrisciano F, Dong E, Guidotti A. Growth arrest and DNA-damage-inducible, beta (GADD45b)-mediated DNA demethylation in major psychosis. Neuropsychopharmacology 2012; 37:531-42. [PMID: 22048458 PMCID: PMC3242315 DOI: 10.1038/npp.2011.221] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Aberrant neocortical DNA methylation has been suggested to be a pathophysiological contributor to psychotic disorders. Recently, a growth arrest and DNA-damage-inducible, beta (GADD45b) protein-coordinated DNA demethylation pathway, utilizing cytidine deaminases and thymidine glycosylases, has been identified in the brain. We measured expression of several members of this pathway in parietal cortical samples from the Stanley Foundation Neuropathology Consortium (SFNC) cohort. We find an increase in GADD45b mRNA and protein in patients with psychosis. In immunohistochemistry experiments using samples from the Harvard Brain Tissue Resource Center, we report an increased number of GADD45b-stained cells in prefrontal cortical layers II, III, and V in psychotic patients. Brain-derived neurotrophic factor IX (BDNF IXabcd) was selected as a readout gene to determine the effects of GADD45b expression and promoter binding. We find that there is less GADD45b binding to the BDNF IXabcd promoter in psychotic subjects. Further, there is reduced BDNF IXabcd mRNA expression, and an increase in 5-methylcytosine and 5-hydroxymethylcytosine at its promoter. On the basis of these results, we conclude that GADD45b may be increased in psychosis compensatory to its inability to access gene promoter regions.
Collapse
Affiliation(s)
- David P Gavin
- Department of Psychiatry, The Psychiatric Institute, University of Illinois at Chicago, Chicago, IL 60612, USA.
| | - Rajiv P Sharma
- Department of Psychiatry, The Psychiatric Institute, University of Illinois at Chicago, Chicago, IL, USA
| | - Kayla A Chase
- Department of Psychiatry, The Psychiatric Institute, University of Illinois at Chicago, Chicago, IL, USA
| | - Francesco Matrisciano
- Department of Psychiatry, The Psychiatric Institute, University of Illinois at Chicago, Chicago, IL, USA
| | - Erbo Dong
- Department of Psychiatry, The Psychiatric Institute, University of Illinois at Chicago, Chicago, IL, USA
| | - Alessandro Guidotti
- Department of Psychiatry, The Psychiatric Institute, University of Illinois at Chicago, Chicago, IL, USA
| |
Collapse
|
9
|
Yiu AP, Rashid AJ, Josselyn SA. Increasing CREB function in the CA1 region of dorsal hippocampus rescues the spatial memory deficits in a mouse model of Alzheimer's disease. Neuropsychopharmacology 2011; 36:2169-86. [PMID: 21734652 DOI: 10.1038/npp.2011.107] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The principal defining feature of Alzheimer's disease (AD) is memory impairment. As the transcription factor CREB (cAMP/Ca(2+) responsive element-binding protein) is critical for memory formation across species, we investigated the role of CREB in a mouse model of AD. We found that TgCRND8 mice exhibit a profound impairment in the ability to form a spatial memory, a process that critically relies on the dorsal hippocampus. Perhaps contributing to this memory deficit, we observed additional deficits in the dorsal hippocampus of TgCRND8 mice in terms of (1) biochemistry (decreased CREB activation in the CA1 region), (2) neuronal structure (decreased spine density and dendritic complexity of CA1 pyramidal neurons), and (3) neuronal network activity (decreased arc mRNA levels following behavioral training). Locally and acutely increasing CREB function in the CA1 region of dorsal hippocampus of TgCRND8 mice was sufficient to restore function in each of these key domains (biochemistry, neuronal structure, network activity, and most importantly, memory formation). The rescue produced by increasing CREB was specific both anatomically and behaviorally and independent of plaque load or Aβ levels. Interestingly, humans with AD show poor spatial memory/navigation and AD brains have disrupted (1) CREB activation, and (2) spine density and dendritic complexity in hippocampal CA1 pyramidal neurons. These parallel findings not only confirm that TgCRND8 mice accurately model key aspects of human AD, but furthermore, suggest the intriguing possibility that targeting CREB may be a useful therapeutic strategy in treating humans with AD.
Collapse
|
10
|
Davidson S, Lear M, Shanley L, Hing B, Baizan-Edge A, Herwig A, Quinn JP, Breen G, McGuffin P, Starkey A, Barrett P, MacKenzie A. Differential activity by polymorphic variants of a remote enhancer that supports galanin expression in the hypothalamus and amygdala: implications for obesity, depression and alcoholism. Neuropsychopharmacology 2011; 36:2211-21. [PMID: 21716262 PMCID: PMC3176579 DOI: 10.1038/npp.2011.93] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The expression of the galanin gene (GAL) in the paraventricular nucleus (PVN) and in the amygdala of higher vertebrates suggests the requirement for highly conserved, but unidentified, regulatory sequences that are critical to allow the galanin gene to control alcohol and fat intake and modulate mood. We used comparative genomics to identify a highly conserved sequence that lay 42 kb 5' of the human GAL transcriptional start site that we called GAL5.1. GAL5.1 activated promoter activity in neurones of the PVN, arcuate nucleus and amygdala that also expressed the galanin peptide. Analysis in neuroblastoma cells demonstrated that GAL5.1 acted as an enhancer of promoter activity after PKC activation. GAL5.1 contained two polymorphisms; rs2513280(C/G) and rs2513281(A/G), that occurred in two allelic combinations (GG or CA) where the dominant GG alelle occurred in 70-83 % of the human population. Intriguingly, both SNPs were found to be in LD (R(2) of 0.687) with another SNP (rs2156464) previously associated with major depressive disorder (MDD). Recreation of these alleles in reporter constructs and subsequent magnetofection into primary rat hypothalamic neurones showed that the CA allele was 40 % less active than the GG allele. This is consistent with the hypothesis that the weaker allele may affect food and alcohol preference. The linkage of the SNPs analysed in this study with a SNP previously associated with MDD together with the functioning of GAL5.1 as a PVN and amygdala specific enhancer represent a significant advance in our ability to understand alcoholism, obesity and major depressive disorder.
Collapse
Affiliation(s)
- Scott Davidson
- School of Medical Sciences, Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen, Scotland, UK
| | - Marissa Lear
- School of Medical Sciences, Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen, Scotland, UK
| | - Lynne Shanley
- School of Medical Sciences, Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen, Scotland, UK
| | - Benjamin Hing
- School of Medical Sciences, Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen, Scotland, UK
| | - Amanda Baizan-Edge
- School of Medical Sciences, Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen, Scotland, UK
| | - Annika Herwig
- The Rowett Institute of Nutrition and Health, Aberdeen, Scotland, UK
| | - John P Quinn
- The Physiological Laboratory, School of Biomedical Sciences, Crown Street, University of Liverpool, Liverpool, UK
| | - Gerome Breen
- MRC SGDP Centre, Institute of Psychiatry, King's College London, DeCrespigny Park, London, UK
| | - Peter McGuffin
- MRC SGDP Centre, Institute of Psychiatry, King's College London, DeCrespigny Park, London, UK
| | - Andrew Starkey
- School of Engineering, Fraser Noble Building, Kings College, University of Aberdeen, Aberdeen, Scotland, UK
| | - Perry Barrett
- The Rowett Institute of Nutrition and Health, Aberdeen, Scotland, UK
| | - Alasdair MacKenzie
- School of Medical Sciences, Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen, Scotland, UK,School of Medical Sciences, Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen, Scotland, UK, Tel: +44 (0)1224 437380, Fax: +44 (0)1224 555719, E-mail:
| |
Collapse
|
11
|
García-Fuster MJ, Flagel SB, Mahmood ST, Mayo LM, Thompson RC, Watson SJ, Akil H. Decreased proliferation of adult hippocampal stem cells during cocaine withdrawal: possible role of the cell fate regulator FADD. Neuropsychopharmacology 2011; 36:2303-17. [PMID: 21796105 DOI: 10.1038/npp.2011.119] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The current study uses an extended access rat model of cocaine self-administration (5-h session per day, 14 days), which elicits several features manifested during the transition to human addiction, to study the neural adaptations associated with cocaine withdrawal. Given that the hippocampus is thought to have an important role in maintaining addictive behavior and appears to be especially relevant to mechanisms associated with withdrawal, this study attempted to understand how extended access to cocaine impacts the hippocampus at the cellular and molecular levels, and how these alterations change over the course of withdrawal (1, 14, and 28 days). Therefore, at the cellular level, we examined the effects of cocaine withdrawal on cell proliferation (Ki-67+ and NeuroD+ cells) in the DG. At the molecular level, we employed a 'discovery' approach with gene expression profiling in the DG to uncover novel molecules possibly implicated in the neural adaptations that take place during cocaine withdrawal. Our results suggest that decreased hippocampal cell proliferation might participate in the adaptations associated with drug removal and identifies 14 days as a critical time-point of cocaine withdrawal. At the 14-day time-point, gene expression profiling of the DG revealed the dysregulation of several genes associated with cell fate regulation, highlighting two new neurobiological correlates (Ascl-1 and Dnmt3b) that accompany cessation of drug exposure. Moreover, the results point to Fas-Associated protein with Death Domain (FADD), a molecular marker previously associated with the propensity to substance abuse and cocaine sensitization, as a key cell fate regulator during cocaine withdrawal. Identifying molecules that may have a role in the restructuring of the hippocampus following substance abuse provides a better understanding of the adaptations associated with cocaine withdrawal and identifies novel targets for therapeutic intervention.
Collapse
|
12
|
Zschocke J, Zimmermann N, Berning B, Ganal V, Holsboer F, Rein T. Antidepressant drugs diversely affect autophagy pathways in astrocytes and neurons--dissociation from cholesterol homeostasis. Neuropsychopharmacology 2011; 36:1754-68. [PMID: 21508931 PMCID: PMC3138654 DOI: 10.1038/npp.2011.57] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2010] [Revised: 02/17/2011] [Accepted: 03/22/2011] [Indexed: 01/25/2023]
Abstract
In the search for antidepressants' (ADs') mechanisms of action beyond their influence on monoaminergic neurotransmission, we analyzed the effects of three structurally and pharmacologically different ADs on autophagic processes in rat primary astrocytes and neurons. Autophagy has a significant role in controlling protein turnover and energy supply. Both, the tricyclic AD amitriptyline (AMI) and the selective serotonin re-uptake inhibitor citalopram (CIT) induced autophagy as mirrored by pronounced upregulation and cellular redistribution of the marker LC3B-II. Redistribution was characterized by formation of LC3B-II-positive structures indicative of autophagosomes, which associated with AVs in a time-dependent manner. Deletion of Atg5, representing a central mediator of autophagy in MEFs, led to abrogation of AMI-induced LC3B-I/II conversion. By contrast, VEN, a selective serotonin and noradrenaline reuptake inhibitor, did not promote autophagic processes in either cell type. The stimulatory impact of AMI on autophagy partly involved class-III PI3 kinase-dependent pathways as 3-methyladenine slightly diminished the effects of AMI. Autophagic flux as defined by autophagosome turnover was vastly undisturbed, and degradation of long-lived proteins was augmented upon AMI treatment. Enhanced autophagy was dissociated from drug-induced alterations in cholesterol homeostasis. Subsequent to AMI- and CIT-mediated autophagy induction, neuronal and glial viability decreased, with neurons showing signs of apoptosis. In conclusion, we report that distinct ADs promote autophagy in neural cells, with important implications on energy homeostasis.
Collapse
Affiliation(s)
- Jürgen Zschocke
- Chaperone Research Group, Max Planck Institute of Psychiatry, Munich, Germany
| | - Nicole Zimmermann
- Chaperone Research Group, Max Planck Institute of Psychiatry, Munich, Germany
| | - Barbara Berning
- Chaperone Research Group, Max Planck Institute of Psychiatry, Munich, Germany
| | - Vanessa Ganal
- Chaperone Research Group, Max Planck Institute of Psychiatry, Munich, Germany
| | - Florian Holsboer
- Chaperone Research Group, Max Planck Institute of Psychiatry, Munich, Germany
| | - Theo Rein
- Chaperone Research Group, Max Planck Institute of Psychiatry, Munich, Germany
| |
Collapse
|
13
|
Chandrasekar V, Dreyer JL. Regulation of MiR-124, Let-7d, and MiR-181a in the accumbens affects the expression, extinction, and reinstatement of cocaine-induced conditioned place preference. Neuropsychopharmacology 2011; 36:1149-64. [PMID: 21307844 DOI: 10.1038/npp.2010.250] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Molecular adaptations underlying drug seeking and relapse remain largely unknown. Studies highlight post-transcriptional modifications mediated by microRNAs (miRNAs) in addiction and other neurological disorders. We have previously shown that chronic cocaine suppresses miR-124 and let-7d and induces the expression of miR-181a in mesolimbic pathway. To further address the role and target gene regulation network of these miRNAs in vivo in cocaine addiction, we developed lentiviral vector (LV)-expressing miRNAs and their corresponding silencers for stable and regulatable miRNA expression. We tested in vivo miRNA gain and loss of function on cocaine-induced conditioned place preference (CPP) by localized LV-miRNA regulation in the nucleus accumbens (NAc). LV-miR-124 and let-7d expression in the NAc attenuates cocaine CPP, whereas LV-miR-181a enhances it. Silencing miRNAs by corresponding LV-miRNA silencers expressing perfect miRNA target sequences inversed this effect on cocaine CPP. Doxycycline treatment for switching off silencer expression abolished the observed behavioral changes. Behavioral changes mediated by LV-miRNA regulation resulted in dynamic alterations in transcription factors, receptors, and other effector genes involved in cocaine-induced plasticity. Our results describe a complex regulatory pathway mediated by miRNAs in cocaine-mediated neuronal adaptations.
Collapse
|
14
|
Onksen JL, Brown EJ, Blendy JA. Selective deletion of a cell cycle checkpoint kinase (ATR) reduces neurogenesis and alters responses in rodent models of behavioral affect. Neuropsychopharmacology 2011; 36:960-9. [PMID: 21248719 PMCID: PMC3077265 DOI: 10.1038/npp.2010.234] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Hippocampal function has been implicated in mood and anxiety disorders, as well as in the response to antidepressant (AD) treatment. However, the significance of new neurons in the therapeutic mechanism of ADs remains unclear. In this study, the proliferation of new neurons was inhibited through conditional deletion of ataxia telangeictasia-mutated and rad-3 related (ATR), a cell cycle checkpoint kinase, and cellular and behavioral outcomes following AD exposure were evaluated. ATR was conditionally deleted by microinjecting a Cre recombinase-expressing virus into the hippocampus of floxed-ATR mice. Behavioral assessment in multiple rodent models of affective state revealed anxiolytic-like behavior in the elevated zero maze, marble burying test, and novelty-induced hypophagia (NIH) test. The efficacy of chronic desipramine (DMI) treatment was evaluated in the NIH test, as this paradigm is thought to be sensitive to increases in neurogenesis by chronic AD exposure. Chronic exposure to DMI reduced hyponeophagia in the NIH test in control mice, whereas DMI had no behavioral effect in ATR-deleted mice. Although DMI did not alter cell proliferation in either group, it did produce a robust increase in dendritic spine density in control mice, indicative of enhanced neuronal plasticity. This effect of DMI on spine density was severely attenuated following ATR deletion. These findings demonstrate that reductions in basal neurogenesis produce an anxiolytic phenotype and reduce AD efficacy in behaviors requiring chronic exposure. Furthermore, attenuated capacity for synaptic remodeling may underlie these behaviors. ATR deletion may serve as a valuable model to study the various proposed roles of newborn neurons in the hippocampus.
Collapse
Affiliation(s)
- Jennifer L Onksen
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Eric J Brown
- Department of Cancer Biology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Julie A Blendy
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA,Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA. Tel: +215 898 0730, Fax: +215 573 2041, E-mail:
| |
Collapse
|
15
|
Abstract
Recent clinical studies demonstrate that serum levels of brain-derived neurotrophic factor (BDNF) are significantly decreased in patients with major depressive disorder (MDD) and that antidepressant treatments reverse this effect, indicating that serum BDNF is a biomarker of MDD. These findings raise the possibility that serum BDNF may also have effects on neuronal activity and behavior, but the functional significance of altered serum BDNF is unknown. To address this issue, we determined the influence of peripheral BDNF administration on depression- and anxiety-like behavior, including the forced swim test (FST), chronic unpredictable stress (CUS)/anhedonia, novelty-induced hypophagia (NIH) test, and elevated-plus maze (EPM). Furthermore, we examined adult hippocampal neurogenesis as well as hippocampal and striatal expression of BDNF, extracellular signal-regulated kinase (ERK) and cAMP response element-binding protein (CREB), in order to determine whether peripherally administered BDNF produces antidepressant-like cellular responses in the brain. Peripheral BDNF administration increased mobility in the FST, attenuated the effects of CUS on sucrose consumption, decreased latency in the NIH test, and increased time spent in the open arms of an EPM. Moreover, adult hippocampal neurogenesis was increased after chronic, peripheral BDNF administration. We also found that BDNF levels as well as expression of pCREB and pERK were elevated in the hippocampus of adult mice receiving peripheral BDNF. Taken together, these results indicate that peripheral/serum BDNF may not only represent a biomarker of MDD, but also have functional consequences on molecular signaling substrates, neurogenesis, and behavior.
Collapse
Affiliation(s)
- Heath D Schmidt
- Departments of Psychiatry and Neurobiology, Laboratory of Molecular Psychiatry, Center for Genes and Behavior, Yale University School of Medicine, Connecticut Mental Health Center, New Haven, CT, USA
| | - Ronald S Duman
- Departments of Psychiatry and Neurobiology, Laboratory of Molecular Psychiatry, Center for Genes and Behavior, Yale University School of Medicine, Connecticut Mental Health Center, New Haven, CT, USA,Departments of Psychiatry and Pharmacology, Yale University School of Medicine, Ribicoff Facilities, 34 Park Street, New Haven, CT 06508, USA, Tel: +1 203 974 7726, Fax: +1 203 974 7724, E-mail:
| |
Collapse
|
16
|
Abstract
Little is known regarding the mechanisms underlying the complex etiology of mood disorders, represented mainly by major depressive disorder and bipolar disorder. The 1996 discovery that lithium inhibits glycogen synthase kinase-3 (GSK3) raised the possibility that impaired inhibition of GSK3 is associated with mood disorders. This is now supported by evidence from animal biochemical, pharmacological, molecular, and behavioral studies and from human post-mortem brain, peripheral tissue, and genetic studies that are reviewed here. Mood disorders may result in part from impairments in mechanisms controlling the activity of GSK3 or GSK3-regulated functions, and disruptions of these regulating systems at different signaling sites may contribute to the heterogeneity of mood disorders. This substantial evidence supports the conclusion that bolstering the inhibitory control of GSK3 is an important component of the therapeutic actions of drugs used to treat mood disorders and that GSK3 is a valid target for developing new therapeutic interventions.
Collapse
|
17
|
Abstract
The study of CpG methylation of genomic DNA in neurons has emerged from the shadow of cancer biology into a fundamental investigation of neuronal physiology. This advance began with the discovery that catalytic and receptor proteins related to the insertion and recognition of this chemical mark are robustly expressed in neurons. At the smallest scale of analysis is the methylation of a single cytosine base within a regulatory cognate sequence. This singular alteration in a nucleotide can profoundly modify transcription factor binding with a consequent effect on the primary 'transcript'. At the single promoter level, the methylation-demethylation of CpG islands and associated alterations in local chromatin assemblies creates a type of cellular 'memory' capable of long-term regulation of transcription particularly in stages of brain development, differentiation, and maturation. Finally, at the genome-wide scale, methylation studies from post-mortem brains suggest that CpG methylation may serve to cap the genome into active and inactive territories introducing a 'masking' function. This may facilitate rapid DNA-protein interactions by ambient transcriptional proteins onto actively networked gene promoters. Beyond this broad portrayal, there are vast gaps in our understanding of the pathway between neuronal activity and CpG methylation. These include the regulation in post-mitotic neurons of the executor proteins, such as the DNA methyltransferases, the elusive and putative demethylases, and the interactions with histone modifying enzymes.
Collapse
|