1
|
Cao YY, Wu LL, Li XN, Yuan YL, Zhao WW, Qi JX, Zhao XY, Ward N, Wang J. Molecular Mechanisms of AMPA Receptor Trafficking in the Nervous System. Int J Mol Sci 2023; 25:111. [PMID: 38203282 PMCID: PMC10779435 DOI: 10.3390/ijms25010111] [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: 11/24/2023] [Revised: 12/15/2023] [Accepted: 12/18/2023] [Indexed: 01/12/2024] Open
Abstract
Synaptic plasticity enhances or reduces connections between neurons, affecting learning and memory. Postsynaptic AMPARs mediate greater than 90% of the rapid excitatory synaptic transmission in glutamatergic neurons. The number and subunit composition of AMPARs are fundamental to synaptic plasticity and the formation of entire neural networks. Accordingly, the insertion and functionalization of AMPARs at the postsynaptic membrane have become a core issue related to neural circuit formation and information processing in the central nervous system. In this review, we summarize current knowledge regarding the related mechanisms of AMPAR expression and trafficking. The proteins related to AMPAR trafficking are discussed in detail, including vesicle-related proteins, cytoskeletal proteins, synaptic proteins, and protein kinases. Furthermore, significant emphasis was placed on the pivotal role of the actin cytoskeleton, which spans throughout the entire transport process in AMPAR transport, indicating that the actin cytoskeleton may serve as a fundamental basis for AMPAR trafficking. Additionally, we summarize the proteases involved in AMPAR post-translational modifications. Moreover, we provide an overview of AMPAR transport and localization to the postsynaptic membrane. Understanding the assembly, trafficking, and dynamic synaptic expression mechanisms of AMPAR may provide valuable insights into the cognitive decline associated with neurodegenerative diseases.
Collapse
Affiliation(s)
- Yi-Yang Cao
- Laboratory of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai 200444, China; (Y.-Y.C.); (X.-N.L.); (Y.-L.Y.); (W.-W.Z.); (J.-X.Q.); (X.-Y.Z.)
| | - Ling-Ling Wu
- School of Medicine, Shanghai University, Shanghai 200444, China;
| | - Xiao-Nan Li
- Laboratory of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai 200444, China; (Y.-Y.C.); (X.-N.L.); (Y.-L.Y.); (W.-W.Z.); (J.-X.Q.); (X.-Y.Z.)
| | - Yu-Lian Yuan
- Laboratory of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai 200444, China; (Y.-Y.C.); (X.-N.L.); (Y.-L.Y.); (W.-W.Z.); (J.-X.Q.); (X.-Y.Z.)
| | - Wan-Wei Zhao
- Laboratory of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai 200444, China; (Y.-Y.C.); (X.-N.L.); (Y.-L.Y.); (W.-W.Z.); (J.-X.Q.); (X.-Y.Z.)
| | - Jing-Xuan Qi
- Laboratory of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai 200444, China; (Y.-Y.C.); (X.-N.L.); (Y.-L.Y.); (W.-W.Z.); (J.-X.Q.); (X.-Y.Z.)
| | - Xu-Yu Zhao
- Laboratory of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai 200444, China; (Y.-Y.C.); (X.-N.L.); (Y.-L.Y.); (W.-W.Z.); (J.-X.Q.); (X.-Y.Z.)
| | - Natalie Ward
- Medical Laboratory, Exceptional Community Hospital, 19060 N John Wayne Pkwy, Maricopa, AZ 85139, USA;
| | - Jiao Wang
- Laboratory of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai 200444, China; (Y.-Y.C.); (X.-N.L.); (Y.-L.Y.); (W.-W.Z.); (J.-X.Q.); (X.-Y.Z.)
| |
Collapse
|
2
|
Schirmer C, Abboud MA, Lee SC, Bass JS, Mazumder AG, Kamen JL, Krishnan V. Home-cage behavior in the Stargazer mutant mouse. Sci Rep 2022; 12:12801. [PMID: 35896608 PMCID: PMC9329369 DOI: 10.1038/s41598-022-17015-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 07/19/2022] [Indexed: 11/09/2022] Open
Abstract
In many childhood-onset genetic epilepsies, seizures are accompanied by neurobehavioral impairments and motor disability. In the Stargazer mutant mouse, genetic disruptions of Cacng2 result in absence-like spike-wave seizures, cerebellar gait ataxia and vestibular dysfunction, which limit traditional approaches to behavioral phenotyping. Here, we combine videotracking and instrumented home-cage monitoring to resolve the neurobehavioral facets of the murine Stargazer syndrome. We find that despite their gait ataxia, stargazer mutants display horizontal hyperactivity and variable rates of repetitive circling behavior. While feeding rhythms, circadian or ultradian oscillations in activity are unchanged, mutants exhibit fragmented bouts of behaviorally defined "sleep", atypical licking dynamics and lowered sucrose preference. Mutants also display an attenuated response to visual and auditory home-cage perturbations, together with profound reductions in voluntary wheel-running. Our results reveal that the seizures and ataxia of Stargazer mutants occur in the context of a more pervasive behavioral syndrome with elements of encephalopathy, repetitive behavior and anhedonia. These findings expand our understanding of the function of Cacng2.
Collapse
Affiliation(s)
- Catharina Schirmer
- Department of Neurology, Baylor College of Medicine, One Baylor Plaza St, Neurosensory BCM: MS NB302, Houston, TX, 77030, USA
| | - Mark A Abboud
- Department of Neurology, Baylor College of Medicine, One Baylor Plaza St, Neurosensory BCM: MS NB302, Houston, TX, 77030, USA
| | - Samuel C Lee
- Department of Neurology, Baylor College of Medicine, One Baylor Plaza St, Neurosensory BCM: MS NB302, Houston, TX, 77030, USA
| | - John S Bass
- Department of Neurology, Baylor College of Medicine, One Baylor Plaza St, Neurosensory BCM: MS NB302, Houston, TX, 77030, USA
| | - Arindam G Mazumder
- Department of Neurology, Baylor College of Medicine, One Baylor Plaza St, Neurosensory BCM: MS NB302, Houston, TX, 77030, USA
| | - Jessica L Kamen
- Department of Neurology, Baylor College of Medicine, One Baylor Plaza St, Neurosensory BCM: MS NB302, Houston, TX, 77030, USA
| | - Vaishnav Krishnan
- Department of Neurology, Baylor College of Medicine, One Baylor Plaza St, Neurosensory BCM: MS NB302, Houston, TX, 77030, USA.
| |
Collapse
|
3
|
Genetic and Epigenetic Markers of Lithium Response. Int J Mol Sci 2022; 23:ijms23031555. [PMID: 35163479 PMCID: PMC8836013 DOI: 10.3390/ijms23031555] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/18/2022] [Accepted: 01/27/2022] [Indexed: 01/25/2023] Open
Abstract
The mood stabilizer lithium represents a cornerstone in the long term treatment of bipolar disorder (BD), although with substantial interindividual variability in clinical response. This variability appears to be modulated by genetics, which has been significantly investigated in the last two decades with some promising findings. In addition, recently, the interest in the role of epigenetics has grown significantly, since the exploration of these mechanisms might allow the elucidation of the gene–environment interactions and explanation of missing heritability. In this article, we provide an overview of the most relevant findings regarding the pharmacogenomics and pharmacoepigenomics of lithium response in BD. We describe the most replicated findings among candidate gene studies, results from genome-wide association studies (GWAS) as well as post-GWAS approaches supporting an association between high genetic load for schizophrenia, major depressive disorder or attention deficit/hyperactivity disorder and poor lithium response. Next, we describe results from studies investigating epigenetic mechanisms, such as changes in methylation or noncoding RNA levels, which play a relevant role as regulators of gene expression. Finally, we discuss challenges related to the search for the molecular determinants of lithium response and potential future research directions to pave the path towards a biomarker guided approach in lithium treatment.
Collapse
|
4
|
Aberrant hippocampal transmission and behavior in mice with a stargazin mutation linked to intellectual disability. Mol Psychiatry 2022; 27:2457-2469. [PMID: 35256745 PMCID: PMC9135633 DOI: 10.1038/s41380-022-01487-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 01/31/2022] [Accepted: 02/14/2022] [Indexed: 11/08/2022]
Abstract
Mutations linked to neurodevelopmental disorders, such as intellectual disability (ID), are frequently found in genes that encode for proteins of the excitatory synapse. Transmembrane AMPA receptor regulatory proteins (TARPs) are AMPA receptor auxiliary proteins that regulate crucial aspects of receptor function. Here, we investigate a mutant form of the TARP family member stargazin, described in an ID patient. Molecular dynamics analyses predicted that the ID-associated stargazin variant, V143L, weakens the overall interface of the AMPAR:stargazin complex and impairs the stability of the complex. Knock-in mice harboring the V143L stargazin mutation manifest cognitive and social deficits and hippocampal synaptic transmission defects, resembling phenotypes displayed by ID patients. In the hippocampus of stargazin V143L mice, CA1 neurons show impaired spine maturation, abnormal synaptic transmission and long-term potentiation specifically in basal dendrites, and synaptic ultrastructural alterations. These data suggest a causal role for mutated stargazin in the pathogenesis of ID and unveil a new role for stargazin in the development and function of hippocampal synapses.
Collapse
|
5
|
Jacobi E, Engelhardt J. Modulation of information processing by AMPA receptor auxiliary subunits. J Physiol 2020; 599:471-483. [DOI: 10.1113/jp276698] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 06/25/2020] [Indexed: 12/13/2022] Open
Affiliation(s)
- Eric Jacobi
- Institute of Pathophysiology University Medical Center of the Johannes Gutenberg University Mainz Mainz Germany
- Focus Program Translational Neurosciences (FTN) University Medical Center of the Johannes Gutenberg‐University Mainz Mainz Germany
| | - Jakob Engelhardt
- Institute of Pathophysiology University Medical Center of the Johannes Gutenberg University Mainz Mainz Germany
- Focus Program Translational Neurosciences (FTN) University Medical Center of the Johannes Gutenberg‐University Mainz Mainz Germany
| |
Collapse
|
6
|
Fortinguerra S, Sorrenti V, Giusti P, Zusso M, Buriani A. Pharmacogenomic Characterization in Bipolar Spectrum Disorders. Pharmaceutics 2019; 12:E13. [PMID: 31877761 PMCID: PMC7022469 DOI: 10.3390/pharmaceutics12010013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 12/14/2019] [Accepted: 12/19/2019] [Indexed: 12/15/2022] Open
Abstract
The holistic approach of personalized medicine, merging clinical and molecular characteristics to tailor the diagnostic and therapeutic path to each individual, is steadily spreading in clinical practice. Psychiatric disorders represent one of the most difficult diagnostic challenges, given their frequent mixed nature and intrinsic variability, as in bipolar disorders and depression. Patients misdiagnosed as depressed are often initially prescribed serotonergic antidepressants, a treatment that can exacerbate a previously unrecognized bipolar condition. Thanks to the use of the patient's genomic profile, it is possible to recognize such risk and at the same time characterize specific genetic assets specifically associated with bipolar spectrum disorder, as well as with the individual response to the various therapeutic options. This provides the basis for molecular diagnosis and the definition of pharmacogenomic profiles, thus guiding therapeutic choices and allowing a safer and more effective use of psychotropic drugs. Here, we report the pharmacogenomics state of the art in bipolar disorders and suggest an algorithm for therapeutic regimen choice.
Collapse
Affiliation(s)
- Stefano Fortinguerra
- Maria Paola Belloni Center for Personalized Medicine, Data Medica Group (Synlab Limited), 35131 Padova, Italy; (S.F.); (V.S.)
- Department of Pharmaceutical & Pharmacological Sciences, University of Padova, 35131 Padova, Italy; (P.G.); (M.Z.)
| | - Vincenzo Sorrenti
- Maria Paola Belloni Center for Personalized Medicine, Data Medica Group (Synlab Limited), 35131 Padova, Italy; (S.F.); (V.S.)
- Department of Pharmaceutical & Pharmacological Sciences, University of Padova, 35131 Padova, Italy; (P.G.); (M.Z.)
- Bendessere™ Study Center, Solgar Italia Multinutrient S.p.A., 35131 Padova, Italy
| | - Pietro Giusti
- Department of Pharmaceutical & Pharmacological Sciences, University of Padova, 35131 Padova, Italy; (P.G.); (M.Z.)
| | - Morena Zusso
- Department of Pharmaceutical & Pharmacological Sciences, University of Padova, 35131 Padova, Italy; (P.G.); (M.Z.)
| | - Alessandro Buriani
- Maria Paola Belloni Center for Personalized Medicine, Data Medica Group (Synlab Limited), 35131 Padova, Italy; (S.F.); (V.S.)
- Department of Pharmaceutical & Pharmacological Sciences, University of Padova, 35131 Padova, Italy; (P.G.); (M.Z.)
| |
Collapse
|
7
|
Miranda A, Shekhtman T, McCarthy M, DeModena A, Leckband SG, Kelsoe JR. Study of 45 candidate genes suggests CACNG2 may be associated with lithium response in bipolar disorder. J Affect Disord 2019; 248:175-179. [PMID: 30738251 PMCID: PMC7292366 DOI: 10.1016/j.jad.2019.01.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 12/15/2018] [Accepted: 01/12/2019] [Indexed: 12/22/2022]
Abstract
BACKGROUND Bipolar disorder is a neuropsychiatric disorder that is characterized by fluctuations between manic and depressive phases. Lithium is the original and best mood stabilizing treatment for bipolar disorder. While its mechanism is not well understood, it is believed to have a strong genetic component, as several studies suggest that lithium responsiveness, in bipolar disorder, is heritable. In this study we aimed to identify genetic variants that are associated with lithium responsiveness in bipolar disorder. METHODS Here we present two cohorts; a retrospective cohort in which patients were surveyed about their response to lithium, and a prospective cohort, in which patients were placed on a lithium monotherapy and monitored for their response to lithium. In both cohorts, patients were stratified into two categories in terms of lithium response; good responders and poor responders. 45 genes were selected based on previous associations with lithium pathways or bipolar disorder and 684 SNPs within these genes were selected to test for association with lithium response. RESULTS While no single SNP was significant after correcting for multiple comparisons, there were several that were nominally significant (p < 0.05). Of these nominally significant SNPs, the most highly significant SNP in both the prospective and retrospective cohorts were found to be in CACNG2, or Stargazin. The second best association with lithium response was several SNPs in NRG1, a gene that has previously been associated with schizophrenia. CONCLUSIONS Evidence for the association of lithium response with SNPs in CACNG2 is consistent with previous findings that have identified CACNG2 as associated with both bipolar disorder and lithium responsiveness.
Collapse
Affiliation(s)
- Alannah Miranda
- Department of Psychiatry, University of California San Diego, La Jolla 92093 CA, USA
| | - Tatyana Shekhtman
- Department of Psychiatry, University of California San Diego, La Jolla 92093 CA, USA; Department of Psychiatry, VA San Diego Healthcare System, La Jolla, CA, USA
| | - Michael McCarthy
- Department of Psychiatry, University of California San Diego, La Jolla 92093 CA, USA; Department of Psychiatry, VA San Diego Healthcare System, La Jolla, CA, USA
| | - Anna DeModena
- Department of Psychiatry, University of California San Diego, La Jolla 92093 CA, USA; Department of Psychiatry, VA San Diego Healthcare System, La Jolla, CA, USA
| | - Susan G Leckband
- Department of Psychiatry, VA San Diego Healthcare System, La Jolla, CA, USA
| | - John R Kelsoe
- Department of Psychiatry, University of California San Diego, La Jolla 92093 CA, USA; Department of Psychiatry, VA San Diego Healthcare System, La Jolla, CA, USA; Institute for Genomic Medicine, University of California San Diego, La Jolla, CA, USA.
| |
Collapse
|
8
|
Corney BPA, Widnall CL, Rees DJ, Davies JS, Crunelli V, Carter DA. Regulatory Architecture of the Neuronal Cacng2/Tarpγ2 Gene Promoter: Multiple Repressive Domains, a Polymorphic Regulatory Short Tandem Repeat, and Bidirectional Organization with Co-regulated lncRNAs. J Mol Neurosci 2018; 67:282-294. [PMID: 30478755 PMCID: PMC6373327 DOI: 10.1007/s12031-018-1208-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 11/08/2018] [Indexed: 12/14/2022]
Abstract
CACNG2 (TARPγ2, Stargazin) is a multi-functional regulator of excitatory neurotransmission and has been implicated in the pathological processes of several brain diseases. Cacng2 function is dependent upon expression level, but currently, little is known about the molecular mechanisms that control expression of this gene. To address this deficit and investigate disease-related gene variants, we have cloned and characterized the rat Cacng2 promoter and have defined three major features: (i) multiple repressive domains that include an array of RE-1 silencing transcription factor (REST) elements, and a calcium regulatory element-binding factor (CaRF) element, (ii) a (poly-GA) short tandem repeat (STR), and (iii) bidirectional organization with expressed lncRNAs. Functional activity of the promoter was demonstrated in transfected neuronal cell lines (HT22 and PC12), but although selective removal of REST and CaRF domains was shown to enhance promoter-driven transcription, the enhanced Cacng2 promoter constructs were still about fivefold weaker than a comparable rat Synapsin-1 promoter sequence. Direct evidence of REST activity at the Cacng2 promoter was obtained through co-transfection with an established dominant-negative REST (DNR) construct. Investigation of the GA-repeat STR revealed polymorphism across both animal strains and species, and size variation was also observed in absence epilepsy disease model cohorts (Genetic Absence Epilepsy Rats, Strasbourg [GAERS] and non-epileptic control [NEC] rats). These data provide evidence of a genotype (STR)-phenotype correlation that may be unique with respect to proximal gene regulatory sequence in the demonstrated absence of other promoter, or 3' UTR variants in GAERS rats. However, although transcriptional regulatory activity of the STR was demonstrated in further transfection studies, we did not find a GAERS vs. NEC difference, indicating that this specific STR length variation may only be relevant in the context of other (Cacna1h and Kcnk9) gene variants in this disease model. Additional studies revealed further (bidirectional) complexity at the Cacng2 promoter, and we identified novel, co-regulated, antisense rat lncRNAs that are paired with Cacng2 mRNA. These studies have provided novel insights into the organization of a synaptic protein gene promoter, describing multiple repressive and modulatory domains that can mediate diverse regulatory inputs.
Collapse
Affiliation(s)
- B P A Corney
- School of Biosciences, Cardiff University, CF103AX, Cardiff, UK
| | - C L Widnall
- School of Biosciences, Cardiff University, CF103AX, Cardiff, UK
| | - D J Rees
- Molecular Neurobiology, Institute of Life Science, Swansea University, Swansea, SA2 8PP, UK
| | - J S Davies
- Molecular Neurobiology, Institute of Life Science, Swansea University, Swansea, SA2 8PP, UK
| | - V Crunelli
- School of Biosciences, Cardiff University, CF103AX, Cardiff, UK
| | - D A Carter
- School of Biosciences, Cardiff University, CF103AX, Cardiff, UK.
| |
Collapse
|
9
|
Amare AT, Schubert KO, Baune BT. Pharmacogenomics in the treatment of mood disorders: Strategies and Opportunities for personalized psychiatry. EPMA J 2017; 8:211-227. [PMID: 29021832 DOI: 10.1007/s13167-017-0112-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 08/11/2017] [Indexed: 01/08/2023]
Abstract
Personalized medicine (personalized psychiatry in a specific setting) is a new model towards individualized care, in which knowledge from genomics and other omic pillars (microbiome, epigenomes, proteome, and metabolome) will be combined with clinical data to guide efforts to new drug development and targeted prescription of the existing treatment options. In this review, we summarize pharmacogenomic studies in mood disorders that may lay the foundation towards personalized psychiatry. In addition, we have discussed the possible strategies to integrate data from omic pillars as a future path to personalized psychiatry. So far, the progress of uncovering single nucleotide polymorphisms (SNPs) underpinning treatment efficacy in mood disorders (e.g., SNPs associated with selective serotonin re-uptake inhibitors or lithium treatment response in patients with bipolar disorder and major depressive disorder) are encouraging, but not adequate. Genetic studies have pointed to a number of SNPs located at candidate genes that possibly influence response to; (a) antidepressants COMT, HTR2A, HTR1A, CNR1, SLC6A4, NPY, MAOA, IL1B, GRIK4, BDNF, GNB3, FKBP5, CYP2D6, CYP2C19, and ABCB1 and (b) mood stabilizers (lithium) 5-HTT, TPH, DRD1, FYN, INPP1, CREB1, BDNF, GSK3β, ARNTL, TIM, DPB, NR3C1, BCR, XBP1, and CACNG2. We suggest three alternative and complementary strategies to implement knowledge gained from pharmacogenomic studies. The first strategy can be to implement diagnostic, therapeutic, or prognostic genetic testing based on candidate genes or gene products. The second alternative is an integrative analysis (systems genomics approach) to combine omics data obtained from the different pillars of omics investigation, including genomics, epigenomes, proteomics, metabolomics and microbiomes. The main goal of system genomics is an identification and understanding of biological pathways, networks, and modules underlying drug-response. The third strategy aims to the development of multivariable diagnostic or prognostic algorithms (tools) combining individual's genomic information (polygenic score) with other predictors (e.g., omics pillars, neuroimaging, and clinical characteristics) to finally predict therapeutic outcomes. An integration of molecular science with that of traditional clinical practice is the way forward to drug discoveries and novel therapeutic approaches and to characterize psychiatric disorders leading to a better predictive, preventive, and personalized medicine (PPPM) in psychiatry. With future advances in the omics technology and methodological developments for data integration, the goal of PPPM in psychiatry is promising.
Collapse
Affiliation(s)
- Azmeraw T Amare
- Discipline of Psychiatry, School of Medicine, University of Adelaide, North Terrace, Adelaide, SA 5005 Australia
| | - Klaus Oliver Schubert
- Discipline of Psychiatry, School of Medicine, University of Adelaide, North Terrace, Adelaide, SA 5005 Australia.,Northern Adelaide Local Health Network, Mental Health Services, Adelaide, SA Australia
| | - Bernhard T Baune
- Discipline of Psychiatry, School of Medicine, University of Adelaide, North Terrace, Adelaide, SA 5005 Australia
| |
Collapse
|
10
|
Higgins GA, Allyn-Feuer A, Georgoff P, Nikolian V, Alam HB, Athey BD. Mining the topography and dynamics of the 4D Nucleome to identify novel CNS drug pathways. Methods 2017; 123:102-118. [PMID: 28385536 DOI: 10.1016/j.ymeth.2017.03.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 03/10/2017] [Indexed: 12/16/2022] Open
Abstract
The pharmacoepigenome can be defined as the active, noncoding province of the genome including canonical spatial and temporal regulatory mechanisms of gene regulation that respond to xenobiotic stimuli. Many psychotropic drugs that have been in clinical use for decades have ill-defined mechanisms of action that are beginning to be resolved as we understand the transcriptional hierarchy and dynamics of the nucleus. In this review, we describe spatial, temporal and biomechanical mechanisms mediated by psychotropic medications. Focus is placed on a bioinformatics pipeline that can be used both for detection of pharmacoepigenomic variants that discretize drug response and adverse events to improve pharmacogenomic testing, and for the discovery of novel CNS therapeutics. This approach integrates the functional topology and dynamics of the transcriptional hierarchy of the pharmacoepigenome, gene variant-driven identification of pharmacogenomic regulatory domains, and mesoscale mapping for the discovery of novel CNS pharmacodynamic pathways in human brain. Examples of the application of this pipeline are provided, including the discovery of valproic acid (VPA) mediated transcriptional reprogramming of neuronal cell fate following injury, and mapping of a CNS pathway glutamatergic pathway for the mood stabilizer lithium. These examples in regulatory pharmacoepigenomics illustrate how ongoing research using the 4D nucleome provides a foundation to further insight into previously unrecognized psychotropic drug pharmacodynamic pathways in the human CNS.
Collapse
Affiliation(s)
- Gerald A Higgins
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, USA
| | - Ari Allyn-Feuer
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, USA
| | - Patrick Georgoff
- Department of Surgery, University of Michigan Medical School, USA
| | - Vahagn Nikolian
- Department of Surgery, University of Michigan Medical School, USA
| | - Hasan B Alam
- Department of Surgery, University of Michigan Medical School, USA
| | - Brian D Athey
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, USA; Michigan Institute for Data Science (MIDAS), USA.
| |
Collapse
|
11
|
|
12
|
Balaraman Y, Lahiri DK, Nurnberger JI. Variants in Ion Channel Genes Link Phenotypic Features of Bipolar Illness to Specific Neurobiological Process Domains. MOLECULAR NEUROPSYCHIATRY 2015; 1:23-35. [PMID: 27602355 DOI: 10.1159/000371886] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 01/05/2015] [Indexed: 11/19/2022]
Abstract
Recent advances in genome-wide association studies are pointing towards a major role for voltage-gated ion channels in neuropsychiatric disorders and, in particular, bipolar disorder (BD). The phenotype of BD is complex, with symptoms during mood episodes and deficits persisting between episodes. We have tried to elucidate the common neurobiological mechanisms associated with ion channel signaling in order to provide a new perspective on the clinical symptoms and possible endophenotypes seen in BD patients. We propose a model in which the multiple variants in genes coding for ion channel proteins would perturb motivational circuits, synaptic plasticity, myelination, hypothalamic-pituitary-adrenal axis function, circadian neuronal rhythms, and energy regulation. These changes in neurobiological mechanisms would manifest in endophenotypes of aberrant reward processing, white matter hyperintensities, deficits in executive function, altered frontolimbic connectivity, increased amygdala activity, increased melatonin suppression, decreased REM latency, and aberrant myo-inositol/ATP shuttling. The endophenotypes result in behaviors of poor impulse control, motivational changes, cognitive deficits, abnormal stress response, sleep disturbances, and energy changes involving different neurobiological process domains. The hypothesis is that these disturbances start with altered neural circuitry during development, following which multiple environmental triggers may disrupt the neuronal excitability balance through an activity-dependent molecular process, resulting in clinical mood episodes.
Collapse
Affiliation(s)
- Yokesh Balaraman
- Institute of Psychiatric Research, Department of Psychiatry, Neuroscience Research Center, Indiana University School of Medicine, Indianapolis, Ind., USA
| | - Debomoy K Lahiri
- Institute of Psychiatric Research, Department of Psychiatry, Neuroscience Research Center, Indiana University School of Medicine, Indianapolis, Ind., USA
| | - John I Nurnberger
- Institute of Psychiatric Research, Department of Psychiatry, Neuroscience Research Center, Indiana University School of Medicine, Indianapolis, Ind., USA
| |
Collapse
|
13
|
Rybakowski JK. Response to lithium in bipolar disorder: clinical and genetic findings. ACS Chem Neurosci 2014; 5:413-21. [PMID: 24625017 DOI: 10.1021/cn5000277] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The use of lithium is a cornerstone for preventing recurrences in bipolar disorder (BD). The response of patients with bipolar disorder to lithium has different levels of magnitude. About one-third of lithium-treated patients are excellent lithium responders (ELR), showing total prevention of the episodes. A number of clinical characteristics were delineated in patients with favorable response to lithium as regards to clinical course, family history of mood disorders, and psychiatric comorbidity. We have also demonstrated that temperamental features of hypomania (a hyperthymic temperament) and a lack of cognitive disorganization predict the best results of lithium prophylaxis. A degree of prevention against manic and depressive episodes has been regarded as an endophenotype for pharmacogenetic studies. The majority of data have been gathered from so-called "candidate" gene studies. The candidates were selected on the basis of neurobiology of bipolar disorder and mechanisms of lithium action including, among others, neurotransmission, intracellular signaling, neuroprotection or circadian rhythms. We demonstrated that response to lithium has been connected with the genotype of BDNF gene and serum BDNF levels and have shown that ELR have normal cognitive functions and serum BDNF levels, even after long-term duration of the illness. A number of genome-wide association studies (GWAS) of BD have been also performed in recent years, some of which also focused on lithium response. The Consortium on Lithium Genetics (ConLiGen) has established the large sample for performing the genome-wide association study (GWAS) of lithium response in BD, and the first results have already been published.
Collapse
Affiliation(s)
- Janusz K. Rybakowski
- Department of Adult Psychiatry, Poznan University of Medical Sciences, 60-572 Poznan, Poland
| |
Collapse
|
14
|
Jan WC, Yang SY, Chuang LC, Lu RB, Lu MK, Sun HS, Kuo PH. Exploring the associations between genetic variants in genes encoding for subunits of calcium channel and subtypes of bipolar disorder. J Affect Disord 2014; 157:80-6. [PMID: 24581832 DOI: 10.1016/j.jad.2013.12.044] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 12/31/2013] [Accepted: 12/31/2013] [Indexed: 01/11/2023]
Abstract
BACKGROUND Associations of two voltage-gated calcium channel (Cav) genes, CACNA1C and CACNB2, were identified for bipolar disorder (BP) in different ethnic groups in recent genome-wide association studies. The current study aimed to evaluate the associations of several Cav genes and subtypes of BP in genetically more homogeneous Taiwanese samples. Additionally, we tested interaction effects among genes that encode for α1, β and γ-subunits of calcium channel. METHODS 8 Cav genes were selected based on evidence in prior association studies and significant linkage regions for BP. 280 BP patients and 200 controls were recruited. Multifactor dimensionality reduction was performed for interaction testing in these discovery samples. Replication was conducted for two markers using additional 495 Taiwanese cases and 1341 controls. RESULTS Weak associations for CACNA1C (rs10848635), CACNA1E (rs10848635), CACNB2 (rs11013860), and CACNG2 (rs2284018) genes were observed. Joint analysis of four markers revealed higher accumulative risk with increasing numbers of risk genotypes an individual endorsed for BP-I (Ptrend=0.006) and BP-II (Ptrend=0.017) disorders. Combined analysis with independent replication samples further supported the association of rs11013860 in CACNB2 with BP subtype I (P=1×10(-6)). Suggestive interactions were found between genes encoded for different subunits of calcium channel (α1, β, and γ). LIMITATIONS Moderate sample size and incomplete markers coverage for the chosen Cav genes. CONCLUSIONS Our results support the involvement of different calcium channel genes in bipolar illness, in particular the beta-subunit in the Asian population. Further investigation of functional property of these genes can contribute on understanding the etiological mechanisms of bipolar illness.
Collapse
Affiliation(s)
- Wen-Chi Jan
- Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taiwan
| | - Shi-Yi Yang
- Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taiwan
| | - Li-Chung Chuang
- Department of Nursing, Cardinal Tien College of Healthcare & Management, I-Lan, Taiwan
| | - Ru-Band Lu
- Department of Psychiatry, National Cheng Kung University and Hospital, Taiwan
| | - Ming-Kun Lu
- Department of Health, Jia Nan Mental Hospital, Taiwan
| | - H Sunny Sun
- Institute of Molecular Medicine, National Cheng Kung University, Taiwan
| | - Po-Hsiu Kuo
- Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taiwan; Research Center for Genes, Environment and Human Health, National Taiwan University, Taipei, Taiwan.
| |
Collapse
|
15
|
Can A, Schulze TG, Gould TD. Molecular actions and clinical pharmacogenetics of lithium therapy. Pharmacol Biochem Behav 2014; 123:3-16. [PMID: 24534415 DOI: 10.1016/j.pbb.2014.02.004] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 02/04/2014] [Accepted: 02/05/2014] [Indexed: 12/21/2022]
Abstract
Mood disorders, including bipolar disorder and depression, are relatively common human diseases for which pharmacological treatment options are often not optimal. Among existing pharmacological agents and mood stabilizers used for the treatment of mood disorders, lithium has a unique clinical profile. Lithium has efficacy in the treatment of bipolar disorder generally, and in particular mania, while also being useful in the adjunct treatment of refractory depression. In addition to antimanic and adjunct antidepressant efficacy, lithium is also proven effective in the reduction of suicide and suicidal behaviors. However, only a subset of patients manifests beneficial responses to lithium therapy and the underlying genetic factors of response are not exactly known. Here we discuss preclinical research suggesting mechanisms likely to underlie lithium's therapeutic actions including direct targets inositol monophosphatase and glycogen synthase kinase-3 (GSK-3) among others, as well as indirect actions including modulation of neurotrophic and neurotransmitter systems and circadian function. We follow with a discussion of current knowledge related to the pharmacogenetic underpinnings of effective lithium therapy in patients within this context. Progress in elucidation of genetic factors that may be involved in human response to lithium pharmacology has been slow, and there is still limited conclusive evidence for the role of a particular genetic factor. However, the development of new approaches such as genome-wide association studies (GWAS), and increased use of genetic testing and improved identification of mood disorder patients sub-groups will lead to improved elucidation of relevant genetic factors in the future.
Collapse
Affiliation(s)
- Adem Can
- Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Thomas G Schulze
- Department of Psychiatry and Psychotherapy, University of Göttingen, Göttingen, Germany; Department of Psychiatry and Behavioral Sciences, Johns Hopkins School of Medicine, Baltimore, MD, United States
| | - Todd D Gould
- Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, United States; Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD, United States; Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, United States.
| |
Collapse
|
16
|
Severino G, Squassina A, Costa M, Pisanu C, Calza S, Alda M, Del Zompo M, Manchia M. Pharmacogenomics of bipolar disorder. Pharmacogenomics 2014; 14:655-74. [PMID: 23570469 DOI: 10.2217/pgs.13.51] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Bipolar disorder (BD) is a lifelong severe psychiatric condition with high morbidity, disability and excess mortality. The longitudinal clinical trajectory of BD is significantly modified by pharmacological treatment(s), both in acute and in long-term stages. However, a large proportion of BD patients have inadequate response to pharmacological treatments. Pharmacogenomic research may lead to the identification of molecular predictors of treatment response. When integrated with clinical information, pharmacogenomic findings may be used in the future to determine the probability of response/nonresponse to treatment on an individual basis. Here we present a selective review of pharmacogenomic findings in BD. In light of the evidence suggesting a genetic effect of lithium reponse in BD, we focused particularly on the pharmacogenomic literature relevant to this trait. The article contributes a detailed overview of the current status of pharmacogenomics in BD and offers a perspective on the challenges that can hinder its transition to personalized healthcare.
Collapse
Affiliation(s)
- Giovanni Severino
- Laboratory of Molecular Genetics, Section of Neuroscience & Clinical Pharmacology, Department of Biomedical Sciences, Sp 8, Sestu-Monserrato, Km 0.700 CA, University of Cagliari, Cagliari, Italy
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Erbin interacts with TARP γ-2 for surface expression of AMPA receptors in cortical interneurons. Nat Neurosci 2013; 16:290-9. [DOI: 10.1038/nn.3320] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 12/24/2012] [Indexed: 12/15/2022]
|
18
|
Abstract
Mood stabilizers form a cornerstone in the long-term treatment of bipolar disorder. The first representative of their family was lithium, still considered a prototype drug for the prevention of manic and depressive recurrences in bipolar disorder. Along with carbamazepine and valproates, lithium belongs to the first generation of mood stabilizers, which appeared in psychiatric treatment in the 1960s. Atypical antipsychotics with mood-stabilizing properties and lamotrigine, which were introduced in the mid-1990 s, form the second generation of such drugs. The response of patients with bipolar disorder to mood stabilizers has different levels of magnitude. About one-third of lithium-treated patients are excellent responders, showing total prevention of the episodes, and these patients are clinically characterized by an episodic clinical course, complete remission, a bipolar family history, low psychiatric co-morbidity and a hyperthymic temperament. It has been suggested that responders to carbamazepine or lamotrigine may differ clinically from responders to lithium. The main phenotype of the response to mood stabilizers is a degree of prevention against recurrences of manic and depressive episodes during long-term treatment. The most specific scale in this respect is the so-called Alda scale, where retrospective assessment of lithium response is scored on a 0-10 scale. The vast majority of data on genetic influences on the response to mood stabilizers has been gathered in relation to lithium. The studies on the mechanisms of action of lithium and on the neurobiology of bipolar disorder have led to the identification of a number of candidate genes. The genes studied for their association with lithium response have been those connected with neurotransmitters (serotonin, dopamine and glutamate), second messengers (phosphatidyl inositol [PI], cyclic adenosine-monophosphate [cAMP] and protein kinase C [PKC] pathways), substances involved in neuroprotection (brain-derived neurotrophic factor [BDNF] and glycogen synthase kinase 3-β [GSK-3β]) and a number of other miscellaneous genes. There are no published pharmacogenomic studies of mood stabilizers other than lithium, except for one study of the X-box binding protein 1 (XBP1) gene in relation to the efficacy of valproate. In recent years, a number of genome-wide association studies (GWAS) in bipolar disorders have been performed and some of those have also focused on lithium response. They suggest roles for the glutamatergic receptor AMPA (GRIA2) gene and the amiloride-sensitive cation channel 1 neuronal (ACCN1) gene in long-term lithium response. A promise for better elucidating the genetics of lithium response has been created by the formation of the Consortium on Lithium Genetics (ConLiGen) to establish the largest sample, to date, for the GWAS of lithium response in bipolar disorder. The sample currently comprises more than 1,200 patients, characterized by their response to lithium treatment according to the Alda scale. Preliminary results from this international study suggest a possible involvement of the sodium bicarbonate transporter (SLC4A10) gene in lithium response. It is concluded that the pharmacogenetics of response to mood stabilizers has recently become a growing field of research, especially so far as the pharmacogenetics of the response to lithium is concerned. Clearly, the ConLiGen project is a highly significant step in this research. Although the results of pharmacogenetic studies are of significant scientific value, their possible practical implications are yet to be seen.
Collapse
|
19
|
Nissen S, Liang S, Shehktman T, Kelsoe JR, Greenwood TA, Nievergelt CM, McKinney R, Shilling PD, Smith EN, Schork NJ, Bloss CS, Nurnberger JI, Edenberg HJ, Foroud T, Koller DL, Gershon ES, Liu C, Badner JA, Scheftner WA, Lawson WB, Nwulia EA, Hipolito M, Coryell W, Rice J, Byerley W, McMahon FJ, Berrettini WH, Potash JB, Zandi PP, Mahon PB, McInnis MG, Zöllner S, Zhang P, Craig DW, Szelinger S, Barrett TB, Schulze TG. Evidence for association of bipolar disorder to haplotypes in the 22q12.3 region near the genes stargazin, IFT27 and parvalbumin. Am J Med Genet B Neuropsychiatr Genet 2012; 159B:941-50. [PMID: 23038240 PMCID: PMC3665332 DOI: 10.1002/ajmg.b.32099] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Accepted: 08/22/2012] [Indexed: 12/13/2022]
Abstract
We have previously reported genome-wide significant linkage of bipolar disorder to a region on 22q12.3 near the marker D22S278. Towards identifying the susceptibility gene, we have conducted a fine-mapping association study of the region in two independent family samples, an independent case-control sample and a genome-wide association dataset. Two hundred SNPs were first examined in a 5 Mb region surrounding the D22S278 marker in a sample of 169 families and analyzed using PLINK. The peak of association was a haplotype near the genes stargazin (CACNG2), intraflagellar transport protein homolog 27 (IFT27) and parvalbumin (PVALB; P = 4.69 × 10(-4)). This peak overlapped a significant haplotype in a family based association study of a second independent sample of 294 families (P = 1.42 × 10(-5)). Analysis of the combined family sample yielded statistically significant evidence of association to a rare three SNP haplotype in the gene IFT27 (P = 8.89 × 10(-6)). Twelve SNPs comprising these haplotypes were genotyped in an independent sample of 574 bipolar I cases and 550 controls. Statistically significant association was found for a haplotype window that overlapped the region from the first two family samples (P = 3.43 × 10(-4)). However, analyses of the two family samples using the program LAMP, found no evidence for association in this region, but did yield significant evidence for association to a haplotype 3' of CACNG2 (P = 1.76 × 10(-6)). Furthermore, no evidence for association was found in a large genome-wide association dataset. The replication of association to overlapping haplotypes in three independent datasets suggests the presence of a bipolar disorder susceptibility gene in this region.
Collapse
Affiliation(s)
- Stephanie Nissen
- Department of Psychiatry, University of California San Diego, La Jolla 92093, California
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
McCarthy MJ, Leckband SG, Kelsoe JR. Pharmacogenetics of lithium response in bipolar disorder. Pharmacogenomics 2011; 11:1439-65. [PMID: 21047205 DOI: 10.2217/pgs.10.127] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Bipolar disorder (BD) is a serious mental illness with well-established, but poorly characterized genetic risk. Lithium is among the best proven mood stabilizer therapies for BD, but treatment responses vary considerably. Based upon these and other findings, it has been suggested that lithium-responsive BD may be a genetically distinct phenotype within the mood disorder spectrum. This assertion has practical implications both for the treatment of BD and for understanding the neurobiological basis of the illness: genetic variation within lithium-sensitive signaling pathways may confer preferential treatment response, and the involved genes may underlie BD in some individuals. Presently, the mechanism of lithium is reviewed with an emphasis on gene-expression changes in response to lithium. Within this context, findings from genetic-association studies designed to identify lithium response genes in BD patients are evaluated. Finally, a framework is proposed by which future pharmacogenetic studies can incorporate advances in genetics, molecular biology and bioinformatics in a pathway-based approach to predicting lithium treatment response.
Collapse
Affiliation(s)
- Michael J McCarthy
- Department of Psychiatry, University of California, San Diego, La Jolla, CA 92093, USA
| | | | | |
Collapse
|
21
|
Jackson AC, Nicoll RA. The expanding social network of ionotropic glutamate receptors: TARPs and other transmembrane auxiliary subunits. Neuron 2011; 70:178-99. [PMID: 21521608 DOI: 10.1016/j.neuron.2011.04.007] [Citation(s) in RCA: 288] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/13/2011] [Indexed: 12/25/2022]
Abstract
Ionotropic glutamate receptors (iGluRs) underlie rapid, excitatory synaptic signaling throughout the CNS. After years of intense research, our picture of iGluRs has evolved from them being companionless in the postsynaptic membrane to them being the hub of dynamic supramolecular signaling complexes, interacting with an ever-expanding litany of other proteins that regulate their trafficking, scaffolding, stability, signaling, and turnover. In particular, the discovery that transmembrane AMPA receptor regulatory proteins (TARPs) are AMPA receptor auxiliary subunits that are critical determinants of their trafficking, gating, and pharmacology has changed the way we think about iGluR function. Recently, a number of novel transmembrane proteins have been uncovered that may also serve as iGluR auxiliary proteins. Here we review pivotal developments in our understanding of the role of TARPs in AMPA receptor trafficking and gating, and provide an overview of how newly discovered transmembrane proteins expand our view of iGluR function in the CNS.
Collapse
Affiliation(s)
- Alexander C Jackson
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94143, USA.
| | | |
Collapse
|
22
|
Affiliation(s)
- Martin B Gill
- Neuroscience Discovery Research, Eli Lilly and Company, Indianapolis, IN, USA.
| | - David S Bredt
- Neuroscience Discovery Research, Eli Lilly and Company, Indianapolis, IN, USA
| |
Collapse
|
23
|
Silberberg G, Ben-Shachar D, Navon R. Genetic analysis of nitric oxide synthase 1 variants in schizophrenia and bipolar disorder. Am J Med Genet B Neuropsychiatr Genet 2010; 153B:1318-28. [PMID: 20645313 DOI: 10.1002/ajmg.b.31112] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Nitric oxide (NO) is a neurotransmitter that acts as a second messenger of the N-methyl-D-aspartate receptor and interacts with the dopaminergic and the serotonergic systems. NO involvement in pathological processes relevant to neuropsychiatric disorders stems from its ability to modulate certain forms of synaptic plasticity, and from its capacity to be transformed to a highly active free radical. Additionally, multiple links have been reported between the NO-producing enzyme, nitric oxide synthase (NOS) 1, and both schizophrenia and bipolar disorder (BPD). RNA and DNA isolated from dorsolateral-prefrontal cortices of schizophrenia patients, bipolar patients and controls (n = 26, 30 and 29, respectively) were donated by the Stanley Foundation Brain Collection. Gene expression was measured by Real-Time-PCR. Genetic polymorphisms were genotyped by restriction-fragment length-polymorphism analysis, and by product-size determination of PCR products amplified with a fluorescent primer.Expression analysis of pan-NOS1, as well as of 2 of its isoforms, "NOS1_1d" and "NOS1_1f", which differ in their first exons and translational strength, revealed a trend for pan-NOS1 over-expression (P = 0.075) in schizophrenia patients (1.33-fold), and significant over-expression (P < 0.05) of NOS1_1d and NOS1_1f in this group (1.54-fold and 1.61-fold, respectively). No expressional alteration was observed in BPD. Polymorphisms at the promoters of NOS1_1d and NOS1_1f, previously shown to be functional in vitro, revealed no significant allelic or genotypic differences among clinical groups and showed no effect on these transcripts' expression. In conclusion, understanding the molecular mechanisms underlying the over-expression of specific NOS1 isoforms, which is unique to schizophrenia, may assist in identifying targets for new drugs.
Collapse
Affiliation(s)
- Gilad Silberberg
- Department of Human Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
| | | | | |
Collapse
|
24
|
Campos-de-Sousa S, Guindalini C, Tondo L, Munro J, Osborne S, Floris G, Pedrazzoli M, Tufik S, Breen G, Collier D. Nuclear receptor rev-erb-{alpha} circadian gene variants and lithium carbonate prophylaxis in bipolar affective disorder. J Biol Rhythms 2010; 25:132-7. [PMID: 20348464 DOI: 10.1177/0748730410362713] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Rev-erb-alpha is one of the key components of the mammalian circadian mechanism; recently, it was also reported to be involved in the biological action of lithium. We investigated whether polymorphisms in the Rev-erb- alpha gene are associated with the long-term efficacy of lithium carbonate therapy in bipolar affective disorder. Seven single nucleotide polymorphisms (SNPs) were genotyped in a well-characterized sample of patients from Sardinia, Italy, who were followed prospectively for up to 27 years. Genotypic and allelic analysis did not show evidence for association between the polymorphisms and the different levels of lithium response. Further analyses grouping the different levels of response demonstrated that when the patients were separated into groups of nonresponders versus individuals who have had at least a minor or modest improvement in frequency of episodes or admissions, there was a significant increase in the frequency of the T allele in the nonresponder group (p = 0.0008). Logistic regression analyses showed that patients carrying at least one copy of the T allele for the rs2314339 marker were shown to be approximately 3.5 times more likely to have no improvement or even a worsening of the illness (odds ratio [OR], 3.56; 95% confidence interval [CI], 1.18-10.76). The results of this study may help to identify potential biological markers that can serve to predict the response of bipolar affective disorder patients to treatment, improving treatment efficacy.
Collapse
Affiliation(s)
- Sara Campos-de-Sousa
- MRC Social Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, UK
| | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Kato AS, Gill MB, Yu H, Nisenbaum ES, Bredt DS. TARPs differentially decorate AMPA receptors to specify neuropharmacology. Trends Neurosci 2010; 33:241-8. [PMID: 20219255 DOI: 10.1016/j.tins.2010.02.004] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Revised: 02/11/2010] [Accepted: 02/13/2010] [Indexed: 11/30/2022]
Abstract
Transmembrane AMPA receptor regulatory proteins (TARPs) are the first identified auxiliary subunits for a neurotransmitter-gated ion channel. Although initial studies found that stargazin, the prototypical TARP, principally chaperones AMPA receptors, subsequent research demonstrated that it also regulates AMPA receptor kinetics and synaptic waveforms. Recent studies have identified a diverse collection of TARP isoforms--types Ia, Ib II--that distinctly regulate AMPA receptor trafficking, gating and neuropharmacology. These TARP isoforms are heterogeneously expressed in specific neuronal populations and can differentially sculpt synaptic transmission and plasticity. Whole-genome analyses also link multiple TARP loci to childhood epilepsy, schizophrenia and bipolar disorder. TARPs emerge as vital components of excitatory synapses that participate both in signal transduction and in neuropsychiatric disorders.
Collapse
Affiliation(s)
- Akihiko S Kato
- Department of Neuroscience, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285-0510, USA
| | | | | | | | | |
Collapse
|
26
|
Covington HE, Vialou V, Nestler EJ. From synapse to nucleus: novel targets for treating depression. Neuropharmacology 2009; 58:683-93. [PMID: 20018197 DOI: 10.1016/j.neuropharm.2009.12.004] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2009] [Accepted: 12/07/2009] [Indexed: 12/28/2022]
Abstract
The need for newer compounds to treat depression is an ever-growing concern due to the enormous societal and financial ramifications of this disorder. Here, we review some of the candidate systems that could potentially be involved in depression, or an inherent resistance to depression termed resilience, and the numerous protein targets for these systems. A substantial body of literature provides strong evidence that neurotrophic factors, glutamate receptors, hypothalamic feeding peptides, nuclear hormone receptors, and epigenetic mechanisms, among others, will make for interesting targets when examining depressive behavior or resilience in preclinical models, and eventually clinical trials. Although some of these targets for depression already appear promising, new waves of more selective compounds for any molecular system should promote a better understanding of this complex disease and perhaps improved treatments.
Collapse
Affiliation(s)
- Herbert E Covington
- Fishberg Department of Neuroscience, Mount Sinai School of Medicine, NY 10029, USA
| | | | | |
Collapse
|
27
|
Perlis RH, Smoller JW, Ferreira MAR, McQuillin A, Bass N, Lawrence J, Sachs GS, Nimgaonkar V, Scolnick EM, Gurling H, Sklar P, Purcell S. A genomewide association study of response to lithium for prevention of recurrence in bipolar disorder. Am J Psychiatry 2009; 166:718-25. [PMID: 19448189 PMCID: PMC3908470 DOI: 10.1176/appi.ajp.2009.08111633] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Lithium remains a first-line treatment for bipolar disorder, but the mechanisms by which it prevents the recurrence of mood episodes are not known. The authors utilized data from a genomewide association study to examine associations between single nucleotide polymorphisms (SNPs) and the outcome of lithium treatment in two cohorts of patients with bipolar I disorder or bipolar II disorder. METHOD The hazard for mood episode recurrence was examined among 1,177 patients with bipolar I disorder or bipolar II disorder, including 458 individuals treated with lithium carbonate or citrate, who were participants in the Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD) cohort. SNPs showing the greatest evidence of association in Cox regression models were then examined for association with positive lithium response among 359 bipolar I or II disorder patients treated with lithium carbonate or citrate in a second cohort from the University College London. RESULTS The strongest association in the STEP-BD cohort (minimum p=5.5 x 10(-7)) was identified for a region on chromosome 10p15 (rs10795189). Of the regions showing suggestive evidence (p<5 x 10(-4)) of association with lithium response, five were further associated with positive lithium response in the University College London cohort, including SNPs in a region on chromosome 4q32 spanning a gene coding for the glutamate/alpha-amino-3-hydroxy-5-methyl-4-isoxazolpropionate (AMPA) receptor GRIA2. CONCLUSIONS Multiple novel loci merit further examination for association with lithium response in bipolar disorder patients, including one region that spans the GRIA2 gene, for which expression has been shown to be regulated by lithium treatment.
Collapse
Affiliation(s)
- Roy H Perlis
- Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Bipolar and major depressive disorder: neuroimaging the developmental-degenerative divide. Neurosci Biobehav Rev 2009; 33:699-771. [PMID: 19428491 DOI: 10.1016/j.neubiorev.2009.01.004] [Citation(s) in RCA: 361] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2009] [Accepted: 01/14/2009] [Indexed: 01/30/2023]
Abstract
Both major depressive disorder and bipolar disorder are the subject of a voluminous imaging and genetics literature. Here, we attempt a comprehensive review of MRI and metabolic PET studies conducted to date on these two disorders, and interpret our findings from the perspective of developmental and degenerative models of illness. Elevated activity and volume loss of the hippocampus, orbital and ventral prefrontal cortex are recurrent themes in the literature. In contrast, dorsal aspects of the PFC tend to display hypometabolism. Ventriculomegaly and white matter hyperintensities are intimately associated with depression in elderly populations and likely have a vascular origin. Important confounding influences are medication, phenotypic and genetic heterogeneity, and technological limitations. We suggest that environmental stress and genetic risk variants interact with each other in a complex manner to alter neural circuitry and precipitate illness. Imaging genetic approaches hold out promise for advancing our understanding of affective illness.
Collapse
|
29
|
Abstract
Treatment of bipolar disorder (BD) has traditionally focused on alleviation of acute symptoms and prevention of future recurrences. Current treatment guide-lines advocate more or less similar treatment algorithms for all patients. Such approach largely ignores the clinical, genetic, and pathophysiological heterogeneity of BD, which makes certain patients more (or less) likely to respond to specific treatments. Variables such as family history, comorbidity, course of illness, quality and duration of previous remissions, physical and medical comorbidity, and side-effects may help in selecting the most effective treatment for an individual patient, yet their value is not recognized by current algorithms. As well, polymorphisms of specific genes may prove useful in predicting treatment outcome and/or understanding the pharmacological mechanisms of mood stabilization. Novel molecular targets have recently emerged from studies of mechanisms of action of available mood stabilizers. They include inhibitors of protein kinase C, inhibitors of glycogen synthase kinase, or medications modulating glutamatergic neurotransmission. As well, treatment targets are moving beyond acute symptoms and prevention of mood episodes. Cognitive deficits, persistence of residual symptoms, and increased mortality of BD are recognized as important for outcome of BD, yet are not always adequately addressed by traditional treatments.
Collapse
Affiliation(s)
- Martin Alda
- Department of Psychiatry, Dalhousie University, 5909 Veterans Memorial Lane, Halifax, Nova Scotia, Canada.
| | | | | | | |
Collapse
|