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Goldberg JM, Loas A, Lippard SJ. Metalloneurochemistry and the Pierian Spring: 'Shallow Draughts Intoxicate the Brain'. Isr J Chem 2016; 56:791-802. [PMID: 28190893 DOI: 10.1002/ijch.201600034] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Metal ions perform critical and diverse functions in nervous system physiology and pathology. The field of metalloneurochemistry aims to understand the mechanistic bases for these varied roles at the molecular level. Here, we review several areas of research that illustrate progress toward achieving this ambitious goal and identify key challenges for the future. We examine the use of lithium as a mood stabilizer, the roles of mobile zinc and copper in the synapse, the interplay of nitric oxide and metals in retrograde signaling, and the regulation of iron homeostasis in the brain. These topics were chosen to demonstrate not only the breadth of the field, but also to highlight opportunities for discovery by studying such complex systems in greater detail. We are beginning to uncover the principles by which receptors and transmitters utilize metal ions to modulate neurotransmission. These advances have revealed exciting new insights into the intricate mechanisms that give rise to learning, memory, and sensory perception, while opening many new avenues for further exploration.
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Affiliation(s)
- Jacob M Goldberg
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (U.S.A.)
| | - Andrei Loas
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (U.S.A.)
| | - Stephen J Lippard
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (U.S.A.)
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Ferruz N, Tresadern G, Pineda-Lucena A, De Fabritiis G. Multibody cofactor and substrate molecular recognition in the myo-inositol monophosphatase enzyme. Sci Rep 2016; 6:30275. [PMID: 27440438 PMCID: PMC4954947 DOI: 10.1038/srep30275] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 06/29/2016] [Indexed: 01/22/2023] Open
Abstract
Molecular recognition is rarely a two-body protein-ligand problem, as it often involves the dynamic interplay of multiple molecules that together control the binding process. Myo-inositol monophosphatase (IMPase), a drug target for bipolar disorder, depends on 3 Mg(2+) ions as cofactor for its catalytic activity. Although the crystallographic pose of the pre-catalytic complex is well characterized, the binding process by which substrate, cofactor and protein cooperate is essentially unknown. Here, we have characterized cofactor and substrate cooperative binding by means of large-scale molecular dynamics. Our study showed the first and second Mg(2+) ions identify the binding pocket with fast kinetics whereas the third ion presents a much higher energy barrier. Substrate binding can occur in cooperation with cofactor, or alone to a binary or ternary cofactor-IMPase complex, although the last scenario occurs several orders of magnitude faster. Our atomic description of the three-body mechanism offers a particularly challenging example of pathway reconstruction, and may prove particularly useful in realistic contexts where water, ions, cofactors or other entities cooperate and modulate the binding process.
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Affiliation(s)
- Noelia Ferruz
- Computational Biophysics Laboratory (GRIB-IMIM), Universitat Pompeu Fabra, Barcelona Biomedical Research Park (PRBB), Doctor Aiguader 88, 08003, Barcelona, Spain
- Acellera, Barcelona Biomedical Research Park, C Dr Aiguader 88, 08003, Barcelona, Spain
| | - Gary Tresadern
- Research Informatics, Janssen Research and Development, Janssen Cilag S A, Calle Jarama 75, Poligono Industrial, Toledo 45007, Spain
| | | | - Gianni De Fabritiis
- Computational Biophysics Laboratory (GRIB-IMIM), Universitat Pompeu Fabra, Barcelona Biomedical Research Park (PRBB), Doctor Aiguader 88, 08003, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluis Companys 23, 08010 Barcelona, Spain
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Kalujnaia S, Hazon N, Cramb G. Myo-inositol phosphate synthase expression in the European eel (Anguilla anguilla) and Nile tilapia (Oreochromis niloticus): effect of seawater acclimation. Am J Physiol Regul Integr Comp Physiol 2016; 311:R287-98. [PMID: 27252471 PMCID: PMC5008666 DOI: 10.1152/ajpregu.00056.2016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 05/25/2016] [Indexed: 11/29/2022]
Abstract
A single MIPS gene (Isyna1/Ino1) exists in eel and tilapia genomes with a single myo-d-inositol 3-phosphate synthase (MIPS) transcript identified in all eel tissues, although two MIPS spliced variants [termed MIPS(s) and MIPS(l)] are found in all tilapia tissues. The larger tilapia transcript [MIPS(l)] results from the inclusion of the 87-nucleotide intron between exons 5 and 6 in the genomic sequence. In most tilapia tissues, the MIPS(s) transcript exhibits much higher abundance (generally >10-fold) with the exception of white skeletal muscle and oocytes, in which the MIPS(l) transcript predominates. SW acclimation resulted in large (6- to 32-fold) increases in mRNA expression for both MIPS(s) and MIPS(l) in all tilapia tissues tested, whereas in the eel, changes in expression were limited to a more modest 2.5-fold increase and only in the kidney. Western blots identified a number of species- and tissue-specific immunoreactive MIPS proteins ranging from 40 to 67 kDa molecular weight. SW acclimation failed to affect the abundance of any immunoreactive protein in any tissue tested from the eel. However, a major 67-kDa immunoreactive protein (presumed to be MIPS) found in tilapia tissues exhibited 11- and 54-fold increases in expression in gill and fin samples from SW-acclimated fish. Immunohistochemical investigations revealed specific immunoreactivity in the gill, fin, skin, and intestine taken from only SW-acclimated tilapia. Immunofluorescence indicated that MIPS was expressed within gill chondrocytes and epithelial cells of the primary filaments, basal epithelial cell layers of the skin and fin, the cytosol of columnar intestinal epithelial and mucous cells, as well as unknown entero-endocrine-like cells.
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Affiliation(s)
- Svetlana Kalujnaia
- School of Medicine, University of St. Andrews, St. Andrews, United Kingdom; and
| | - Neil Hazon
- School of Biology, University of St. Andrews, St. Andrews, United Kingdom
| | - Gordon Cramb
- School of Medicine, University of St. Andrews, St. Andrews, United Kingdom; and
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Osmoregulatory inositol transporter SMIT1 modulates electrical activity by adjusting PI(4,5)P2 levels. Proc Natl Acad Sci U S A 2016; 113:E3290-9. [PMID: 27217553 DOI: 10.1073/pnas.1606348113] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Myo-inositol is an important cellular osmolyte in autoregulation of cell volume and fluid balance, particularly for mammalian brain and kidney cells. We find it also regulates excitability. Myo-inositol is the precursor of phosphoinositides, key signaling lipids including phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2]. However, whether myo-inositol accumulation during osmoregulation affects signaling and excitability has not been fully explored. We found that overexpression of the Na(+)/myo-inositol cotransporter (SMIT1) and myo-inositol supplementation enlarged intracellular PI(4,5)P2 pools, modulated several PI(4,5)P2-dependent ion channels including KCNQ2/3 channels, and attenuated the action potential firing of superior cervical ganglion neurons. Further experiments using the rapamycin-recruitable phosphatase Sac1 to hydrolyze PI(4)P and the P4M probe to visualize PI(4)P suggested that PI(4)P levels increased after myo-inositol supplementation with SMIT1 expression. Elevated relative levels of PIP and PIP2 were directly confirmed using mass spectrometry. Inositol trisphosphate production and release of calcium from intracellular stores also were augmented after myo-inositol supplementation. Finally, we found that treatment with a hypertonic solution mimicked the effect we observed with SMIT1 overexpression, whereas silencing tonicity-responsive enhancer binding protein prevented these effects. These results show that ion channel function and cellular excitability are under regulation by several "physiological" manipulations that alter the PI(4,5)P2 setpoint. We demonstrate a previously unrecognized linkage between extracellular osmotic changes and the electrical properties of excitable cells.
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Abstract
All living cells require membrane proteins that act as conduits for the regulated transport of ions, solutes and other small molecules across the cell membrane. Ion channels provide a pore that permits often rapid, highly selective and tightly regulated movement of ions down their electrochemical gradient. In contrast, active transporters can move moieties up their electrochemical gradient. The secondary active transporters (such as SLC superfamily solute transporters) achieve this by coupling uphill movement of the substrate to downhill movement of another ion, such as sodium. The primary active transporters (including H(+)/K(+)-ATPases and Na(+)/K(+)-ATPases) utilize ATP hydrolysis as an energy source to power uphill transport. It is well known that proteins in each of these classes work in concert with members of the other classes to ensure, for example, ion homeostasis, ion secretion and restoration of ion balance following action potentials. More recently, evidence is emerging of direct physical interaction between true ion channels, and some primary or secondary active transporters. Here, we review the first known members of this new class of macromolecular complexes that we term "chansporters", explore their biological roles and discuss the pathophysiological consequences of their disruption. We compare functional and/or physical interactions between the ubiquitous KCNQ1 potassium channel and various active transporters, and examine other newly discovered chansporter complexes that suggest we may be seeing the tip of the iceberg in a newly emerging signaling modality.
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Affiliation(s)
- Daniel L Neverisky
- a Bioelectricity Laboratory, Departments of Pharmacology and Physiology and Biophysics, School of Medicine, University of California , Irvine , CA , USA
| | - Geoffrey W Abbott
- a Bioelectricity Laboratory, Departments of Pharmacology and Physiology and Biophysics, School of Medicine, University of California , Irvine , CA , USA
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Abstract
In this chapter, we review the mechanism of action of lithium salts from a chemical perspective. A description on how lithium salts are used to treat mental illnesses, in particular bipolar disorder, and other disease states is provided. Emphasis is not placed on the genetics and the psychopharmacology of the ailments for which lithium salts have proven to be beneficial. Rather we highlight the application of chemical methodologies for the characterization of the cellular targets of lithium salts and their distribution in tissues.
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Schiebler M, Brown K, Hegyi K, Newton SM, Renna M, Hepburn L, Klapholz C, Coulter S, Obregón-Henao A, Henao Tamayo M, Basaraba R, Kampmann B, Henry KM, Burgon J, Renshaw SA, Fleming A, Kay RR, Anderson KE, Hawkins PT, Ordway DJ, Rubinsztein DC, Floto RA. Functional drug screening reveals anticonvulsants as enhancers of mTOR-independent autophagic killing of Mycobacterium tuberculosis through inositol depletion. EMBO Mol Med 2015; 7:127-39. [PMID: 25535254 PMCID: PMC4328644 DOI: 10.15252/emmm.201404137] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Mycobacterium tuberculosis (MTB) remains a major challenge to global health made worse by the spread of multidrug resistance. We therefore examined whether stimulating intracellular killing of mycobacteria through pharmacological enhancement of macroautophagy might provide a novel therapeutic strategy. Despite the resistance of MTB to killing by basal autophagy, cell-based screening of FDA-approved drugs revealed two anticonvulsants, carbamazepine and valproic acid, that were able to stimulate autophagic killing of intracellular M. tuberculosis within primary human macrophages at concentrations achievable in humans. Using a zebrafish model, we show that carbamazepine can stimulate autophagy in vivo and enhance clearance of M. marinum, while in mice infected with a highly virulent multidrug-resistant MTB strain, carbamazepine treatment reduced bacterial burden, improved lung pathology and stimulated adaptive immunity. We show that carbamazepine induces antimicrobial autophagy through a novel, evolutionarily conserved, mTOR-independent pathway controlled by cellular depletion of myo-inositol. While strain-specific differences in susceptibility to in vivo carbamazepine treatment may exist, autophagy enhancement by repurposed drugs provides an easily implementable potential therapy for the treatment of multidrug-resistant mycobacterial infection.
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Affiliation(s)
- Mark Schiebler
- Department of Medicine, Cambridge Institute for Medical Research University of Cambridge, Cambridge, UK
| | - Karen Brown
- Department of Medicine, Cambridge Institute for Medical Research University of Cambridge, Cambridge, UK Cambridge Centre for Lung Infection, Papworth Hospital, Cambridge, UK
| | - Krisztina Hegyi
- Department of Medicine, Cambridge Institute for Medical Research University of Cambridge, Cambridge, UK
| | - Sandra M Newton
- Department of Paediatric Infectious Diseases and Allergy, Imperial College London, London, UK
| | - Maurizio Renna
- Department of Medical Genetics, Cambridge Institute for Medical Research University of Cambridge, Cambridge, UK
| | - Lucy Hepburn
- Department of Medicine, Cambridge Institute for Medical Research University of Cambridge, Cambridge, UK
| | - Catherine Klapholz
- Department of Medicine, Cambridge Institute for Medical Research University of Cambridge, Cambridge, UK
| | - Sarah Coulter
- Department of Medicine, Cambridge Institute for Medical Research University of Cambridge, Cambridge, UK
| | - Andres Obregón-Henao
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Marcela Henao Tamayo
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Randall Basaraba
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Beate Kampmann
- Department of Paediatric Infectious Diseases and Allergy, Imperial College London, London, UK
| | - Katherine M Henry
- Department of Infection and Immunity, University of Sheffield Western Bank, Sheffield, UK
| | - Joseph Burgon
- Department of Infection and Immunity, University of Sheffield Western Bank, Sheffield, UK
| | - Stephen A Renshaw
- Department of Infection and Immunity, University of Sheffield Western Bank, Sheffield, UK
| | - Angeleen Fleming
- Department of Medical Genetics, Cambridge Institute for Medical Research University of Cambridge, Cambridge, UK
| | - Robert R Kay
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Karen E Anderson
- The Inositide Laboratory, Babraham Institute Babraham Research Campus, Cambridge, UK
| | - Phillip T Hawkins
- The Inositide Laboratory, Babraham Institute Babraham Research Campus, Cambridge, UK
| | - Diane J Ordway
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - David C Rubinsztein
- Department of Medical Genetics, Cambridge Institute for Medical Research University of Cambridge, Cambridge, UK
| | - Rodrigo Andres Floto
- Department of Medicine, Cambridge Institute for Medical Research University of Cambridge, Cambridge, UK Cambridge Centre for Lung Infection, Papworth Hospital, Cambridge, UK
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58
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Polenova T, Gupta R, Goldbourt A. Magic angle spinning NMR spectroscopy: a versatile technique for structural and dynamic analysis of solid-phase systems. Anal Chem 2015; 87:5458-69. [PMID: 25794311 PMCID: PMC4890703 DOI: 10.1021/ac504288u] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Magic Angle Spinning (MAS) NMR spectroscopy is a powerful method for analysis of a broad range of systems, including inorganic materials, pharmaceuticals, and biomacromolecules. The recent developments in MAS NMR instrumentation and methodologies opened new vistas to atomic-level characterization of a plethora of chemical environments previously inaccessible to analysis, with unprecedented sensitivity and resolution.
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Affiliation(s)
- Tatyana Polenova
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, United States
| | - Rupal Gupta
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, United States
| | - Amir Goldbourt
- School of Chemistry, Tel Aviv University, Ramat Aviv 69978, Tel Aviv, Israel
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59
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Schneider S. Inositol transport proteins. FEBS Lett 2015; 589:1049-58. [DOI: 10.1016/j.febslet.2015.03.012] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2015] [Revised: 03/05/2015] [Accepted: 03/18/2015] [Indexed: 12/27/2022]
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60
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Damri O, Sade Y, Toker L, Bersudsky Y, Belmaker RH, Agam G, Azab AN. Molecular effects of lithium are partially mimicked by inositol-monophosphatase (IMPA)1 knockout mice in a brain region-dependent manner. Eur Neuropsychopharmacol 2015; 25:425-34. [PMID: 25748680 DOI: 10.1016/j.euroneuro.2014.06.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Accepted: 06/24/2014] [Indexed: 11/30/2022]
Abstract
We have previously shown that homozygote knockout (KO) of inositol-monophosphatase1 (IMPA1) results in lithium (Li)-like behavior. We now aimed to find out whether Li-treated mice and IMPA1 KO mice exhibit neurochemical similarity at the gene- and protein-expression level. Hippocampal and frontal cortex B-cell lymphoma (Bcl-2), Bcl-2-associated X protein (BAX), P53, Perodoxin2 (PRDX2), myristoylated alanine-rich C kinase substrate (MARCKS) and neuropeptide Y (NPY) mRNA levels, and hippocampal, frontal cortex and hypothalamic cytokine levels, all previously reported to be affected by lithium treatment, were measured in three groups of mice: wildtype (WT) on regular-food (RF), WT on Li-supplemented food (Li-treated) and IMPA1-KOs. Hippocampal and frontal cortex Bcl-2 and MARCKS were the only genes commonly affected (downregulated) by Li and IMPA1 KO; Bcl-2 - by 28% and 19%, respectively; MARCKS - by about 20% in both regions. The effect of Li and of IMPA1 KO on cytokine levels differed among the three brain areas studied. Only in the hippocampus both interventions exerted similar effects. Frontal cortex cytokine levels were unaffected neither by Li nor by IMPA1 KO. Similar changes in Bcl-2 and MARCKS but not in PRDX2 and NPY following both Li-treatment and IMPA1 KO suggest a mechanism different than inositol-monophosphatase1 inhibition for Li׳s effect on the latter genes. The cytokine levels results suggest that the mechanism mediating Li׳s effect on the inflammatory system differs among brain regions. Only in the hippocampus the results favor the involvement of the phosphatidylinositol (PI) cycle.
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Affiliation(s)
- O Damri
- Department of Clinical Biochemistry and Pharmacology, Beer-Sheva, Israel; Psychiatry Research Unit, Beer-Sheva, Israel; Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel; Mental Health Center, Beer-Sheva, Israel
| | - Y Sade
- Department of Clinical Biochemistry and Pharmacology, Beer-Sheva, Israel; Psychiatry Research Unit, Beer-Sheva, Israel; Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel; Mental Health Center, Beer-Sheva, Israel
| | - L Toker
- Department of Clinical Biochemistry and Pharmacology, Beer-Sheva, Israel; Psychiatry Research Unit, Beer-Sheva, Israel; Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel; Mental Health Center, Beer-Sheva, Israel
| | - Y Bersudsky
- Psychiatry Research Unit, Beer-Sheva, Israel; Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel; Mental Health Center, Beer-Sheva, Israel
| | - R H Belmaker
- Psychiatry Research Unit, Beer-Sheva, Israel; Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - G Agam
- Department of Clinical Biochemistry and Pharmacology, Beer-Sheva, Israel; Psychiatry Research Unit, Beer-Sheva, Israel; Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel; Mental Health Center, Beer-Sheva, Israel.
| | - A N Azab
- Department of Clinical Biochemistry and Pharmacology, Beer-Sheva, Israel; Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
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61
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Ashhad S, Johnston D, Narayanan R. Activation of InsP₃ receptors is sufficient for inducing graded intrinsic plasticity in rat hippocampal pyramidal neurons. J Neurophysiol 2014; 113:2002-13. [PMID: 25552640 DOI: 10.1152/jn.00833.2014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 12/29/2014] [Indexed: 11/22/2022] Open
Abstract
The synaptic plasticity literature has focused on establishing necessity and sufficiency as two essential and distinct features in causally relating a signaling molecule to plasticity induction, an approach that has been surprisingly lacking in the intrinsic plasticity literature. In this study, we complemented the recently established necessity of inositol trisphosphate (InsP3) receptors (InsP3R) in a form of intrinsic plasticity by asking if InsP3R activation was sufficient to induce intrinsic plasticity in hippocampal neurons. Specifically, incorporation of d-myo-InsP3 in the recording pipette reduced input resistance, maximal impedance amplitude, and temporal summation but increased resonance frequency, resonance strength, sag ratio, and impedance phase lead. Strikingly, the magnitude of plasticity in all these measurements was dependent on InsP3 concentration, emphasizing the graded dependence of such plasticity on InsP3R activation. Mechanistically, we found that this InsP3-induced plasticity depended on hyperpolarization-activated cyclic nucleotide-gated channels. Moreover, this calcium-dependent form of plasticity was critically reliant on the release of calcium through InsP3Rs, the influx of calcium through N-methyl-d-aspartate receptors and voltage-gated calcium channels, and on the protein kinase A pathway. Our results delineate a causal role for InsP3Rs in graded adaptation of neuronal response dynamics, revealing novel regulatory roles for the endoplasmic reticulum in neural coding and homeostasis.
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Affiliation(s)
- Sufyan Ashhad
- Cellular Neurophysiology Laboratory, Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India; and
| | - Daniel Johnston
- Center for Learning and Memory, The University of Texas at Austin, Austin, Texas
| | - Rishikesh Narayanan
- Cellular Neurophysiology Laboratory, Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India; and
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Plotnikov EY, Silachev DN, Zorova LD, Pevzner IB, Jankauskas SS, Zorov SD, Babenko VA, Skulachev MV, Zorov DB. Lithium salts — Simple but magic. BIOCHEMISTRY (MOSCOW) 2014; 79:740-9. [DOI: 10.1134/s0006297914080021] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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63
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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.
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Affiliation(s)
- Janusz K. Rybakowski
- Department of Adult Psychiatry, Poznan University of Medical Sciences, 60-572 Poznan, Poland
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64
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Han P, Xu M, Chang J, Chakravorty N, Wu C, Xiao Y. Lithium release from β-tricalcium phosphate inducing cementogenic and osteogenic differentiation of both hPDLCs and hBMSCs. Biomater Sci 2014; 2:1230-1243. [DOI: 10.1039/c4bm00111g] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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65
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Comparative modeling and virtual screening for the identification of novel inhibitors for myo-inositol-1-phosphate synthase. Mol Biol Rep 2014; 41:5039-52. [PMID: 24752405 DOI: 10.1007/s11033-014-3370-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 04/05/2014] [Indexed: 12/20/2022]
Abstract
Myo-inositol-1-phosphate (MIP) synthase is a key enzyme in the myo-inositol biosynthesis pathway. Disruption of the inositol signaling pathway is associated with bipolar disorders. Previous work suggested that MIP synthase could be an attractive target for the development of anti-bipolar drugs. Inhibition of this enzyme could possibly help in reducing the risk of a disease in patients. With this objective, three dimensional structure of the protein was modeled followed by the active site prediction. For the first time, computational studies were carried out to obtain structural insights into the interactive behavior of this enzyme with ligands. Virtual screening was carried out using FILTER, ROCS and EON modules of the OpenEye scientific software. Natural products from the ZINC database were used for the screening process. Resulting compounds were docked into active site of the target protein using FRED (Fast Rigid Exhaustive Docking) and GOLD (Genetic Optimization for Ligand Docking) docking programs. The analysis indicated extensive hydrogen bonding network and hydrophobic interactions which play a significant role in ligand binding. Four compounds are shortlisted and their binding assay analysis is underway.
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66
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Bogdanova OV, Abdullah O, Kanekar S, Bogdanov VB, Prescot AP, Renshaw PF. Neurochemical alterations in frontal cortex of the rat after one week of hypobaric hypoxia. Behav Brain Res 2014; 263:203-9. [PMID: 24486259 PMCID: PMC4699295 DOI: 10.1016/j.bbr.2014.01.027] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Revised: 01/16/2014] [Accepted: 01/20/2014] [Indexed: 12/16/2022]
Abstract
Residing at high altitude may lead to reduced blood oxygen saturation in the brain and altered metabolism in frontal cortical brain areas, probably due to chronic hypobaric hypoxia. These changes may underlie the increased rates of depression and suicidal behavior that have been associated with life at higher altitudes. To test the hypothesis that hypobaric hypoxia is responsible for development of mood disorders due to alterations in neurochemistry, we assessed depression-like behavior in parallel to levels of brain metabolites in rats housed at simulated altitude. 32 female Sprague Dawley rats were housed either in a hypobaric hypoxia chamber at 10,000 ft of simulated altitude for 1 week or at local conditions (4500 ft of elevation in Salt Lake City, Utah). Depression-like behavior was assessed using the forced swim test (FST) and levels of neurometabolites were estimated by in vivo proton magnetic resonance spectroscopy in the frontal cortex, the striatum and the hippocampus at baseline and after a week of exposure to hypobaric hypoxia. After hypoxia exposure the animals demonstrated increased immobility behavior and shortened latency to immobility in the FST. Elevated ratios of myo-inositol, glutamate, and the sum of myo-inositol and glycine to total creatine were observed in the frontal cortex of hypoxia treated rats. A decrease in the ratio of alanine to total creatine was also noted. This study shows that hypoxia induced alterations in frontal lobe brain metabolites, aggravated depression-like behavior and might be a factor in increased rates of psychiatric disorders observed in populations living at high altitudes.
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Affiliation(s)
- Olena V Bogdanova
- Brain Institute, University of Utah, 383 Colorow Drive, Salt Lake City 84108, UT USA.
| | - Osama Abdullah
- Department of Bioengineering, University of Utah, 36 S. Wasatch Drive, Salt Lake City 84112, UT USA
| | - Shami Kanekar
- Brain Institute, University of Utah, 383 Colorow Drive, Salt Lake City 84108, UT USA; Psychiatry Department, University of Utah, 383 Colorow Drive, Salt Lake City 84108, UT USA
| | - Volodymyr B Bogdanov
- INRA, Nutrition et Neurobiologie Intégrée and University Bordeaux, Nutrition et Neurobiologie Intégrée, UMR 1286, 146 rue Léo-Saignat, Bordeaux Cedex 33076, France
| | - Andrew P Prescot
- Brain Institute, University of Utah, 383 Colorow Drive, Salt Lake City 84108, UT USA; Department of Radiology, University of Utah, 30 North 1900 East, Salt Lake City 84132, UT USA
| | - Perry F Renshaw
- Brain Institute, University of Utah, 383 Colorow Drive, Salt Lake City 84108, UT USA; Psychiatry Department, University of Utah, 383 Colorow Drive, Salt Lake City 84108, UT USA; VISN19 MIRECC Salt Lake City UAMC, 500 Foothill Drive, Salt Lake City 84148, UT USA
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67
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Ohnishi T, Murata T, Watanabe A, Hida A, Ohba H, Iwayama Y, Mishima K, Gondo Y, Yoshikawa T. Defective craniofacial development and brain function in a mouse model for depletion of intracellular inositol synthesis. J Biol Chem 2014; 289:10785-10796. [PMID: 24554717 DOI: 10.1074/jbc.m113.536706] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
myo-Inositol is an essential biomolecule that is synthesized by myo-inositol monophosphatase (IMPase) from inositol monophosphate species. The enzymatic activity of IMPase is inhibited by lithium, a drug used for the treatment of mood swings seen in bipolar disorder. Therefore, myo-inositol is thought to have an important role in the mechanism of bipolar disorder, although the details remain elusive. We screened an ethyl nitrosourea mutant mouse library for IMPase gene (Impa) mutations and identified an Impa1 T95K missense mutation. The mutant protein possessed undetectable enzymatic activity. Homozygotes died perinatally, and E18.5 embryos exhibited striking developmental defects, including hypoplasia of the mandible and asymmetric fusion of ribs to the sternum. Perinatal lethality and morphological defects in homozygotes were rescued by dietary myo-inositol. Rescued homozygotes raised on normal drinking water after weaning exhibited a hyper-locomotive trait and prolonged circadian periods, as reported in rodents treated with lithium. Our mice should be advantageous, compared with those generated by the conventional gene knock-out strategy, because they carry minimal genomic damage, e.g. a point mutation. In conclusion, our results reveal critical roles for intracellular myo-inositol synthesis in craniofacial development and the maintenance of proper brain function. Furthermore, this mouse model for cellular inositol depletion could be beneficial for understanding the molecular mechanisms underlying the clinical effect of lithium and myo-inositol-mediated skeletal development.
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Affiliation(s)
- Tetsuo Ohnishi
- Laboratory for Molecular Psychiatry, RIKEN Brain Science Institute, Wako, Saitama 351-0198.
| | - Takuya Murata
- Mutagenesis and Genomics Team, RIKEN BioResource Center, Tsukuba, Ibaraki 305-0074
| | - Akiko Watanabe
- Laboratory for Molecular Psychiatry, RIKEN Brain Science Institute, Wako, Saitama 351-0198
| | - Akiko Hida
- Department of Psychophysiology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Kodaira, Tokyo 187-8553, Japan
| | - Hisako Ohba
- Laboratory for Molecular Psychiatry, RIKEN Brain Science Institute, Wako, Saitama 351-0198
| | - Yoshimi Iwayama
- Laboratory for Molecular Psychiatry, RIKEN Brain Science Institute, Wako, Saitama 351-0198
| | - Kazuo Mishima
- Department of Psychophysiology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Kodaira, Tokyo 187-8553, Japan
| | - Yoichi Gondo
- Mutagenesis and Genomics Team, RIKEN BioResource Center, Tsukuba, Ibaraki 305-0074
| | - Takeo Yoshikawa
- Laboratory for Molecular Psychiatry, RIKEN Brain Science Institute, Wako, Saitama 351-0198
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68
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Tomita H, Ziegler ME, Kim HB, Evans SJ, Choudary PV, Li JZ, Meng F, Dai M, Myers RM, Neal CR, Speed TP, Barchas JD, Schatzberg AF, Watson SJ, Akil H, Jones EG, Bunney WE, Vawter MP. G protein-linked signaling pathways in bipolar and major depressive disorders. Front Genet 2013; 4:297. [PMID: 24391664 PMCID: PMC3870297 DOI: 10.3389/fgene.2013.00297] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 12/05/2013] [Indexed: 01/03/2023] Open
Abstract
The G-protein linked signaling system (GPLS) comprises a large number of G-proteins, G protein-coupled receptors (GPCRs), GPCR ligands, and downstream effector molecules. G-proteins interact with both GPCRs and downstream effectors such as cyclic adenosine monophosphate (cAMP), phosphatidylinositols, and ion channels. The GPLS is implicated in the pathophysiology and pharmacology of both major depressive disorder (MDD) and bipolar disorder (BPD). This study evaluated whether GPLS is altered at the transcript level. The gene expression in the dorsolateral prefrontal (DLPFC) and anterior cingulate (ACC) were compared from MDD, BPD, and control subjects using Affymetrix Gene Chips and real time quantitative PCR. High quality brain tissue was used in the study to control for confounding effects of agonal events, tissue pH, RNA integrity, gender, and age. GPLS signaling transcripts were altered especially in the ACC of BPD and MDD subjects. Transcript levels of molecules which repress cAMP activity were increased in BPD and decreased in MDD. Two orphan GPCRs, GPRC5B and GPR37, showed significantly decreased expression levels in MDD, and significantly increased expression levels in BPD. Our results suggest opposite changes in BPD and MDD in the GPLS, “activated” cAMP signaling activity in BPD and “blunted” cAMP signaling activity in MDD. GPRC5B and GPR37 both appear to have behavioral effects, and are also candidate genes for neurodegenerative disorders. In the context of the opposite changes observed in BPD and MDD, these GPCRs warrant further study of their brain effects.
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Affiliation(s)
- Hiroaki Tomita
- Department of Psychiatry and Human Behavior, University of California Irvine, CA, USA ; Department of Biological Psychiatry, Tohoku University Sendai, Japan ; Functional Genomics Laboratory, Department of Psychiatry and Human Behavior, University of California Irvine CA, USA
| | - Mary E Ziegler
- Department of Psychiatry and Human Behavior, University of California Irvine, CA, USA ; Functional Genomics Laboratory, Department of Psychiatry and Human Behavior, University of California Irvine CA, USA
| | - Helen B Kim
- Department of Psychiatry and Human Behavior, University of California Irvine, CA, USA ; Functional Genomics Laboratory, Department of Psychiatry and Human Behavior, University of California Irvine CA, USA
| | - Simon J Evans
- Molecular and Behavioral Neurosciences Institute, University of Michigan Ann Arbor, MI, USA
| | | | - Jun Z Li
- Molecular and Behavioral Neurosciences Institute, University of Michigan Ann Arbor, MI, USA
| | - Fan Meng
- Molecular and Behavioral Neurosciences Institute, University of Michigan Ann Arbor, MI, USA
| | - Manhong Dai
- Molecular and Behavioral Neurosciences Institute, University of Michigan Ann Arbor, MI, USA
| | | | - Charles R Neal
- Molecular and Behavioral Neurosciences Institute, University of Michigan Ann Arbor, MI, USA ; John A. Burns School of Medicine, University of Hawaii Honolulu, HI, USA
| | - Terry P Speed
- Department of Statistics, University of California Berkeley CA, USA
| | - Jack D Barchas
- Department of Psychiatry, Weill Cornell Medical College New York, NY, USA
| | - Alan F Schatzberg
- Department of Psychiatry and Behavioral Sciences, Stanford University Palo Alto, CA, USA
| | - Stanley J Watson
- Molecular and Behavioral Neurosciences Institute, University of Michigan Ann Arbor, MI, USA
| | - Huda Akil
- Molecular and Behavioral Neurosciences Institute, University of Michigan Ann Arbor, MI, USA
| | - Edward G Jones
- Center for Neuroscience, University of California Davis, CA, USA
| | - William E Bunney
- Department of Psychiatry and Human Behavior, University of California Irvine, CA, USA
| | - Marquis P Vawter
- Department of Psychiatry and Human Behavior, University of California Irvine, CA, USA ; Functional Genomics Laboratory, Department of Psychiatry and Human Behavior, University of California Irvine CA, USA
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69
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Smith AJ, Kim SH, Duggirala NK, Jin J, Wojtas L, Ehrhart J, Giunta B, Tan J, Zaworotko MJ, Shytle RD. Improving lithium therapeutics by crystal engineering of novel ionic cocrystals. Mol Pharm 2013; 10:4728-38. [PMID: 24191685 PMCID: PMC3850245 DOI: 10.1021/mp400571a] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Current United States Food and Drug Administration (FDA)-approved lithium salts are plagued with a narrow therapeutic window. Recent attempts to find alternative drugs have identified new chemical entities, but lithium's polypharmacological mechanisms for treating neuropsychiatric disorders are highly debated and are not yet matched. Thus, re-engineering current lithium solid forms in order to optimize performance represents a low cost and low risk approach to the desired therapeutic outcome. In this contribution, we employed a crystal engineering strategy to synthesize the first ionic cocrystals (ICCs) of lithium salts with organic anions. We are unaware of any previous studies that have assessed the biological efficacy of any ICCs, and encouragingly we found that the new speciation did not negatively affect established bioactivities of lithium. We also observed that lithium ICCs exhibit modulated pharmacokinetics compared to lithium carbonate. Indeed, the studies detailed herein represent an important advancement in a crystal engineering approach to a new generation of lithium therapeutics.
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Affiliation(s)
- Adam J Smith
- Center of Excellence for Aging and Brain Repair, Department of Neurosurgery and Brain Repair, Morsani College of Medicine, University of South Florida , Tampa, Florida 33612, United States
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70
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Lueke K, Kaiser T, Svetlitchny A, Welzel O, Wenzel EM, Tyagarajan S, Kornhuber J, Groemer TW. Basic presynaptic functions in hippocampal neurons are not affected by acute or chronic lithium treatment. J Neural Transm (Vienna) 2013; 121:211-9. [DOI: 10.1007/s00702-013-1087-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 08/27/2013] [Indexed: 01/27/2023]
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71
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Komoroski RA, Lindquist DM, Pearce JM. Lithium compartmentation in brain by 7Li MRS: effect of total lithium concentration. NMR IN BIOMEDICINE 2013; 26:1152-1157. [PMID: 23401319 PMCID: PMC3665720 DOI: 10.1002/nbm.2929] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 01/03/2013] [Accepted: 01/06/2013] [Indexed: 06/01/2023]
Abstract
In previous work at 4.7 T, the individual components of biexponential (7) Li transverse (T2 ) spin relaxation in rat brain in vivo were tentatively identified with intra- and extracellular Li. The goal in this work was to estimate Li's compartmental distribution as a function of total Li concentration in brain from the biexponential decays. Here a localized, biexponential (7) Li T2 MR spin-relaxation study with isotopically enriched (7) LiCl is reported in rat brain in vivo at 7 T. Additionally, a simple linear interpolation using the biexponential T2 values to estimate intracellular Li from individual monoexponential T2 decays was assessed. Intracellular T2 was 14.8 ± 4.3 ms and extracellular T2 was 295 ± 61 ms. The fraction of intracellular brain Li ranged from 37.3 to 64.8% (mean 54.5 ± 6.7%) and did not correlate with total Li concentration. The estimated intracellular Li concentration ranged from 47 to 80% (mean 68.3 ± 8.5%) of the total brain Li concentration and was highly correlated with it. The monoexponential estimates of the intracellular-Li fractions and derived concentrations averaged about 15% higher than the corresponding biexponential estimates. This work supports the previous conclusion that a large fraction of Li in the brain is within the intracellular compartment.
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Affiliation(s)
- Richard A Komoroski
- Center for Imaging Research, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0583, USA.
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72
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Abstract
Lithium has been used for the treatment of mood disorders for over 60 years, yet the exact mechanisms by which it exerts its therapeutic effects remain unclear. Two enzymatic chains or pathways emerge as targets for lithium: inositol monophosphatase within the phosphatidylinositol signalling pathway and the protein kinase glycogen synthase kinase 3. Lithium inhibits these enzymes through displacing the normal cofactor magnesium, a vital regulator of numerous signalling pathways. Here we provide an overview of evidence, supporting a role for the inhibition of glycogen synthase kinase 3 and inositol monophosphatase in the pharmacodynamic actions of lithium. We also explore how inhibition of these enzymes by lithium can lead to downstream effects of clinical relevance, both for mood disorders and neurodegenerative diseases. Establishing a better understanding of lithium's mechanisms of action may allow the development of more effective and more tolerable pharmacological agents for the treatment of a range of mental illnesses, and provide clearer insight into the pathophysiology of such disorders.
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Affiliation(s)
- Kayleigh M Brown
- Institute of Psychiatry, King's College London, PO Box 63, De Crespigny Park, Denmark Hill, London SE5 8AF, UK
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73
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Abstract
We review recent developments in the acute and long-term treatment of bipolar disorder and identify promising future routes to therapeutic innovation. Overall, advances in drug treatment remain quite modest. Antipsychotic drugs are effective in the acute treatment of mania; their efficacy in the treatment of depression is variable with the clearest evidence for quetiapine. Despite their widespread use, considerable uncertainty and controversy remains about the use of antidepressant drugs in the management of depressive episodes. Lithium has the strongest evidence for long-term relapse prevention; the evidence for anticonvulsants such as divalproex and lamotrigine is less robust and there is much uncertainty about the longer term benefits of antipsychotics. Substantial progress has been made in the development and assessment of adjunctive psychosocial interventions. Long-term maintenance and possibly acute stabilisation of depression can be enhanced by the combination of psychosocial treatments with drugs. The development of future treatments should consider both the neurobiological and psychosocial mechanisms underlying the disorder. We should continue to repurpose treatments and to recognise the role of serendipity. We should also investigate optimum combinations of pharmacological and psychotherapeutic treatments at different stages of the illness. Clarification of the mechanisms by which different treatments affect sleep and circadian rhythms and their relation with daily mood fluctuations is likely to help with the treatment selection for individual patients. To be economically viable, existing psychotherapy protocols need to be made briefer and more efficient for improved scalability and sustainability in widespread implementation.
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Affiliation(s)
- John R Geddes
- Department of Psychiatry, University of Oxford, Oxford, UK (Prof J R Geddes MD, Prof D J Miklowitz PhD); and Division of Child and Adolescent Psychiatry, University of California, Los Angeles (UCLA) School of Medicine, Los Angeles, CA, USA (Prof D J Miklowitz PhD)
| | - David J Miklowitz
- Department of Psychiatry, University of Oxford, Oxford, UK (Prof J R Geddes MD, Prof D J Miklowitz PhD); and Division of Child and Adolescent Psychiatry, University of California, Los Angeles (UCLA) School of Medicine, Los Angeles, CA, USA (Prof D J Miklowitz PhD)
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74
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Eliav U, Goldbourt A. The combined effect of quadrupolar and dipolar interactions on the excitation and evolution of triple quantum coherences in ⁷Li solid state magic angle spinning NMR. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2013; 230:227-235. [PMID: 23481861 DOI: 10.1016/j.jmr.2013.01.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Revised: 01/17/2013] [Accepted: 01/27/2013] [Indexed: 06/01/2023]
Abstract
Magic-angle spinning triple-quantum NMR spectra of lithium-7 provide enhanced spectral dispersion for the inherent low chemical shift range of this nucleus, while maintaining linewidths, which are free of any quadrupolar broadening to first order. Since the quadrupolar interaction of (7)Li is very small, in the order of the radio frequency nutation frequencies and only moderately larger than the spinning rates, such spectra are also only marginally affected by the second order quadrupolar interaction under large magnetic fields. In the current study we demonstrate that the existence of two and more proximate (7)Li spins, as encountered in many materials, affects both excitation and evolution of triple-quantum coherences due to the combined effect of quadrupolar and homonuclear dipolar interactions. We show that the generation of (7)Li triple-quantum coherences using two π/2 pulses separated by one-half rotor period is superior in such cases to a single pulse excitation since the excitation time is shorter; thus the maximum signal is only marginally affected by the homonuclear dipolar couplings. When the quadrupolar-dipolar cross terms dominate the spectra, single- and triple-quantum lineshapes are very similar and therefore a true gain in dispersion is maintained in the latter spectrum. The effects of quadrupolar-dipolar cross terms are experimentally demonstrated by comparing a natural abundance and a (6)Li-diluted samples of lithium acetate, resulting in the possibility of efficient excitation of triple quantum coherences over longer periods of time, and in longer life times of triple-quantum coherences.
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Affiliation(s)
- Uzi Eliav
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Ramat Aviv 69978, Tel Aviv, Israel.
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75
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Cytotoxicity of intracellular aβ42 amyloid oligomers involves Ca2+ release from the endoplasmic reticulum by stimulated production of inositol trisphosphate. J Neurosci 2013; 33:3824-33. [PMID: 23447594 DOI: 10.1523/jneurosci.4367-12.2013] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Oligomeric forms of β-amyloid (Aβ(42)) peptides associated with Alzheimer's disease (AD) disrupt cellular Ca(2+) regulation by liberating Ca(2+) into the cytosol from both extracellular and intracellular sources. We elucidated the actions of intracellular Aβ by imaging Ca(2+) responses to injections of Aβ oligomers into Xenopus oocytes. Two types of signal were observed: (1) local, "channel-like" transients dependent on extracellular Ca(2+) influx, which resembled signals from amlyoid pores formed by extracellular application of oligomers; and (2) local transients and global Ca(2+) waves, resembling Ca(2+) puffs and waves mediated by inositol trisphosphate (IP(3)). The latter responses were suppressed by antagonists of the IP(3) receptor (caffeine and heparin), pretreatment with the G(i)(o)-protein inhibitor pertussis toxin, and pretreatment with lithium to deplete membrane inositol lipids. We show that G-protein-mediated stimulation of IP(3) production and consequent liberation of Ca(2+) from the endoplasmic reticulum by intracellular Aβ oligomers is cytotoxic, potentially representing a novel pathological mechanism in AD which may be further exacerbated by AD-linked mutations in presenilins to promote opening of IP(3) receptor/channels.
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76
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Mullins RJ, Xu S, Pereira EFR, Mamczarz J, Albuquerque EX, Gullapalli RP. Delayed hippocampal effects from a single exposure of prepubertal guinea pigs to sub-lethal dose of chlorpyrifos: a magnetic resonance imaging and spectroscopy study. Neurotoxicology 2013; 36:42-8. [PMID: 23411083 DOI: 10.1016/j.neuro.2013.02.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 01/29/2013] [Accepted: 02/03/2013] [Indexed: 01/09/2023]
Abstract
This study was designed to test the hypothesis that in vivo magnetic resonance imaging (MRI) and spectroscopy (MRS) can detect in adulthood the neurotoxic effects of a single exposure of prepubertal guinea pigs to the organophosphorus pesticide chlorpyrifos. Twelve female guinea pigs were given either a single dose of chlorpyrifos (0.6×LD50 or 300mg/kg, sc) or peanut oil (vehicle; 0.5ml/kg, sc) at 35-40 days of age. One year after the exposure, the animals were tested in the Morris water maze. Three days after the end of the behavioral testing, the metabolic and structural integrity of the brain of the animals was examined by means of MRI/MRS. In the Morris water maze, the chlorpyrifos-exposed guinea pigs showed significant memory deficit. Although no significant anatomical differences were found between the chlorpyrifos-exposed guinea pigs and the control animals by in vivo MRI, the chlorpyrifos-exposed animals showed significant decreases in hippocampal myo-inositol concentration using MRS. The present results indicate that a single sub-lethal exposure of prepubertal guinea pigs to the organophosphorus pesticide chlorpyrifos can lead to long-term memory deficits that are accompanied by significant reductions in the levels of hippocampal myo-inositol.
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Affiliation(s)
- Roger J Mullins
- Department of Diagnostic Radiology & Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, United States
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77
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Wang Y, Wang Y, Li M, Xu P, Gu T, Ma T, Gu S. (1)H NMR-based metabolomics exploring biomarkers in rat cerebrospinal fluid after cerebral ischemia/reperfusion. MOLECULAR BIOSYSTEMS 2013; 9:431-9. [PMID: 23340987 DOI: 10.1039/c2mb25224d] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
In our study, metabolomics was used to investigate biochemical changes in the early stages of rats focal cerebral ischemia/reperfusion (I/R) injury. Cerebrospinal fluid (CSF) samples at 0, 0.5, 1, 3, and 6 h of reperfusion (n = 10), based on (1)H NMR spectroscopy and multivariate data analyses, were tested to analyze the changing of metabolites during the early disease process. Partial least squares-discriminant analysis scores plots of the (1)H NMR data revealed clear differences among the experiment groups. Combining the results of the loading plot and t-test, we found that twenty-seven metabolites were changed significantly (p < 0.05) in the CSF samples among the different groups. Among that, the potential biomarkers in CSF of ischemic rats were: acetic acid, 3-hydroxyisovaleric acid, 3-hydroxybutyric acid, choline, l-alanine, creatine, creatinine, glycine, pyruvic acid, glycerol, glutamic acid, d-fructose, l-lactic acid and acetone. These findings help us understand the biochemical metabolite changes in CSF of I/R rats in early stages. What's more, metabolomics may, therefore, have the potential to be developed into a clinically useful diagnostic tool of ischemic brain injury.
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Affiliation(s)
- Yun Wang
- Jiangsu Key Laboratory of Anaesthesia, XuZhou Medical College, XuZhou, JiangSu, China
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78
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Wang X, Hirao H. ONIOM (DFT:MM) Study of the Catalytic Mechanism of myo-Inositol Monophosphatase: Essential Role of Water in Enzyme Catalysis in the Two-Metal Mechanism. J Phys Chem B 2013; 117:833-42. [DOI: 10.1021/jp312483n] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Xiaoqing Wang
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore
637371
| | - Hajime Hirao
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore
637371
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79
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Lam YF, Fukui N, Sugai T, Watanabe J, Watanabe Y, Suzuki Y, Someya T. Pharmacogenomics in Psychiatric Disorders. Pharmacogenomics 2013. [DOI: 10.1016/b978-0-12-391918-2.00006-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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80
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Suganthi M, Sangeetha G, Benson CS, Babu SD, Sathyavathy A, Ramadoss S, Ravi Sankar B. In vitro mechanisms involved in the regulation of cell survival by lithium chloride and IGF-1 in human hormone-dependent breast cancer cells (MCF-7). Toxicol Lett 2012; 214:182-91. [DOI: 10.1016/j.toxlet.2012.08.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 08/17/2012] [Accepted: 08/25/2012] [Indexed: 01/24/2023]
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81
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Seelan RS, Pisano MM, Greene RM, Casanova MF, Parthasarathy RN. Differential methylation of the gene encoding myo-inositol 3-phosphate synthase (Isyna1) in rat tissues. Epigenomics 2012; 3:111-24. [PMID: 21841945 DOI: 10.2217/epi.10.73] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AIMS Myo-inositol levels are frequently altered in several brain disorders. Myo-inositol 3-phosphate synthase, encoded by the Isyna1 gene, catalyzes the synthesis of myo-inositol in cells. Very little is known about the mechanisms regulating Isyna1 expression in brain and other tissues. In this study, we have examined the role of DNA methylation in regulating Isyna1 expression in rat tissues. MATERIALS & METHODS Transfection analysis using in vitro methylated promoter constructs, Southern blot analysis of genomic DNA from various tissues digested with a methylation-sensitive enzyme and CpG methylation profiling of genomic DNA from different tissues were used to determine differential methylation of Isyna1 in tissues. Transfection analysis using plasmids harboring mutated CpG residues in the 5'-upstream region of Isyna1 was used to identify critical residues mediating promoter activity. RESULTS The -700 bp to -500 bp region (region 1) of Isyna1 exhibited increased methylation in brain cortex compared with other tissues; it also exhibited sex-specific methylation differences between matched male and female brain cortices. Mutation analysis identified one CpG residue in region 1 necessary for promoter activity in neuronal cells. A tissue-specific differentially methylated region (T-DMR) was found to be localized between +450 bp and +650 bp (region 3). This DMR was comparatively highly methylated in spleen, moderately methylated in brain cortex and poorly methylated in testis, consistent with mRNA levels observed in these tissues. CONCLUSION Rat Isyna1 exhibits tissue-specific DNA methylation. Brain DNA was uniquely methylated in the 5'-upstream region and displayed gender specificity. A T-DMR was identified within the gene body of Isyna1. These findings suggest that Isyna1 is regulated, in part, by DNA methylation and that significant alterations in methylation patterns during development could have a major impact on inositol phosphate synthase expression in later life.
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Affiliation(s)
- Ratnam S Seelan
- Molecular, Cellular & Craniofacial Biology, Birth Defects Center, University of Louisville, 501 S. Preston St, KY 40292, USA.
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82
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Isolation and identification of myo-inositol crystals from dragon fruit (Hylocereus polyrhizus). Molecules 2012; 17:4583-94. [PMID: 22510607 PMCID: PMC6268417 DOI: 10.3390/molecules17044583] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Revised: 04/05/2012] [Accepted: 04/06/2012] [Indexed: 12/22/2022] Open
Abstract
Crystals isolated from Hylocereus polyrhizus were analyzed using four different approaches—X-ray Crystallography, High Performance Liquid Chromatography (HPLC), Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS) and Nuclear Magnetic Resonance (NMR) and identified as myo-inositol. The X-ray crystallography analysis showed that the unit-cell parameters were: a = 6.6226 (3) Å, b = 12.0462 (5) Å, c = 18.8942 (8) Å, α = 90.00, β = 93.98, δ = 90.00. The purity of the crystals were checked using HPLC, whereupon a clean single peak was obtained at 4.8 min with a peak area of 41232 μV*s. The LC-MS/MS technique, which is highly sensitive and selective, was used to provide a comparison of the isolated crystals with a myo-inositol standard where the results gave an identical match for both precursor and product ions. NMR was employed to confirm the molecular structure and conformation of the crystals, and the results were in agreement with the earlier results in this study. The discovery of myo-inositol crystals in substantial amount in H. polyrhizus has thus far not been reported and this is an important finding which will increase the marketability and importance of H. polyrhizus as a crop with a wide array of health properties.
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83
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Haimovich A, Eliav U, Goldbourt A. Determination of the Lithium Binding Site in Inositol Monophosphatase, the Putative Target for Lithium Therapy, by Magic-Angle-Spinning Solid-State NMR. J Am Chem Soc 2012; 134:5647-51. [DOI: 10.1021/ja211794x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Anat Haimovich
- Raymond and Beverly Sackler Faculty of Exact Sciences,
School of Chemistry, Tel Aviv University, Tel Aviv, Israel
| | - Uzi Eliav
- Raymond and Beverly Sackler Faculty of Exact Sciences,
School of Chemistry, Tel Aviv University, Tel Aviv, Israel
| | - Amir Goldbourt
- Raymond and Beverly Sackler Faculty of Exact Sciences,
School of Chemistry, Tel Aviv University, Tel Aviv, Israel
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84
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Singh KK, De Rienzo G, Drane L, Mao Y, Flood Z, Madison J, Ferreira M, Bergen S, King C, Sklar P, Sive H, Tsai LH. Common DISC1 polymorphisms disrupt Wnt/GSK3β signaling and brain development. Neuron 2012; 72:545-58. [PMID: 22099458 DOI: 10.1016/j.neuron.2011.09.030] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/20/2011] [Indexed: 12/31/2022]
Abstract
Disrupted in Schizophrenia-1 (DISC1) is a candidate gene for psychiatric disorders and has many roles during brain development. Common DISC1 polymorphisms (variants) are associated with neuropsychiatric phenotypes including altered cognition, brain structure, and function; however, it is unknown how this occurs. Here, we demonstrate using mouse, zebrafish, and human model systems that DISC1 variants are loss of function in Wnt/GSK3β signaling and disrupt brain development. The DISC1 variants A83V, R264Q, and L607F, but not S704C, do not activate Wnt signaling compared with wild-type DISC1 resulting in decreased neural progenitor proliferation. In zebrafish, R264Q and L607F could not rescue DISC1 knockdown-mediated aberrant brain development. Furthermore, human lymphoblast cell lines endogenously expressing R264Q displayed impaired Wnt signaling. Interestingly, S704C inhibited the migration of neurons in the developing neocortex. Our data demonstrate DISC1 variants impair Wnt signaling and brain development and elucidate a possible mechanism for their role in neuropsychiatric phenotypes.
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Affiliation(s)
- Karun K Singh
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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85
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Harwood AJ. Prolyl oligopeptidase, inositol phosphate signalling and lithium sensitivity. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2012; 10:333-9. [PMID: 21222625 PMCID: PMC3267164 DOI: 10.2174/187152711794653779] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Accepted: 09/25/2010] [Indexed: 11/22/2022]
Abstract
Inhibition of prolyl oligopeptidase (PO) elevates inositol phosphate (IP) signalling and reduces cell sensitivity to lithium (Li+). This review discusses recent evidence that shows PO acts via the multiple inositol polyphosphate phosphatase (MIPP) to regulate gene expression. As a consequence, PO inhibition causes both a transient, rapid increase in I(1,4,5)P3 and a long-term elevation of IP signalling. This pathway is evolutionary conserved, being present in both the social amoeba Dictyostelium and human cell systems, and has potential implications for mental health.
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86
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Zhang Y, Filiou MD, Reckow S, Gormanns P, Maccarrone G, Kessler MS, Frank E, Hambsch B, Holsboer F, Landgraf R, Turck CW. Proteomic and metabolomic profiling of a trait anxiety mouse model implicate affected pathways. Mol Cell Proteomics 2011; 10:M111.008110. [PMID: 21862759 DOI: 10.1074/mcp.m111.008110] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Depression and anxiety disorders affect a great number of people worldwide. Whereas singular factors have been associated with the pathogenesis of psychiatric disorders, growing evidence emphasizes the significance of dysfunctional neural circuits and signaling pathways. Hence, a systems biology approach is required to get a better understanding of psychiatric phenotypes such as depression and anxiety. Furthermore, the availability of biomarkers for these disorders is critical for improved diagnosis and monitoring treatment response. In the present study, a mouse model presenting with robust high versus low anxiety phenotypes was subjected to thorough molecular biomarker and pathway discovery analyses. Reference animals were metabolically labeled with the stable (15)N isotope allowing an accurate comparison of protein expression levels between the high anxiety-related behavior versus low anxiety-related behavior mouse lines using quantitative mass spectrometry. Plasma metabolomic analyses identified a number of small molecule biomarkers characteristic for the anxiety phenotype with particular focus on myo-inositol and glutamate as well as the intermediates involved in the tricarboxylic acid cycle. In silico analyses suggested pathways and subnetworks as relevant for the anxiety phenotype. Our data demonstrate that the high anxiety-related behavior and low anxiety-related behavior mouse model is a valuable tool for anxiety disorder drug discovery efforts.
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87
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Lithium, an anti-psychotic drug, greatly enhances the generation of induced pluripotent stem cells. Cell Res 2011; 21:1424-35. [PMID: 21727907 PMCID: PMC3193456 DOI: 10.1038/cr.2011.108] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Somatic cells can be reprogrammed into induced pluripotent stem cells (iPSCs) by defined factors. The low efficiency of reprogramming and genomic integration of oncogenes and viral vectors limited the potential application of iPSCs. Here we report that Lithium (Li), a drug used to treat mood disorders, greatly enhances iPSC generation from both mouse embryonic fibroblast and human umbilical vein endothelial cells. Li facilitates iPSC generation with one (Oct4) or two factors (OS or OK). The effect of Li on promoting reprogramming only partially depends on its major target GSK3β. Unlike other GSK3β inhibitors, Li not only increases the expression of Nanog, but also enhances the transcriptional activity of Nanog. We also found that Li exerts its effect by promoting epigenetic modifications via downregulation of LSD1, a H3K4-specific histone demethylase. Knocking down LSD1 partially mimics Li's effect in enhancing reprogramming. Our results not only provide a straightforward method to improve the iPSC generation efficiency, but also identified a histone demethylase as a critical modulator for somatic cell reprogramming.
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88
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Moreno-Baylach MJ, Puttonen KA, Tenorio-Laranga J, Venäläinen JI, Storvik M, Forsberg MM, García-Horsman JA. Prolyl endopeptidase is involved in cellular signalling in human neuroblastoma SH-SY5Y cells. Neurosignals 2011; 19:97-109. [PMID: 21487212 DOI: 10.1159/000326342] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Accepted: 02/22/2011] [Indexed: 11/19/2022] Open
Abstract
Prolyl endopeptidase (PREP), probably acting through the inositol cycle, has been implicated in memory and learning. However, the physiological role of PREP is unknown. It has been shown that PREP expression, regulated in cerebellar granule cells, has probably a role in cell proliferation and differentiation. Here, we report the levels and subcellular distribution of PREP in human neuroblastoma SH-SY5Y cells in proliferating conditions and under differentiation induced by retinoic acid (RA). We analysed the levels of cell signalling intermediates, growth behavior and gene expression, and differentiation morphology changes, upon PREP inhibition. After induction of differentiation, PREP activity was found decreased in the nucleus but increased to high levels in the cytoplasm, due in part to increased PREP transcription. The levels of inositol (1,4,5)-trisphosphate revealed no correlation with PREP activity, but phosphorylated extracellular signal-regulated kinases 1 and 2 were decreased by PREP inhibition during early stages of differentiation. Morphological evaluation indicated that PREP inhibition retarded the onset of differentiation. PREP activity regulated gene expression of protein synthesis machinery, intracellular transport and kinase complexes. We conclude that PREP is a regulatory target and a regulatory element in cell signalling. This is the first report of a direct influence of a cell signalling molecule, RA, on PREP expression.
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89
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Abstract
Existing psychotropic medications for the treatment of mental illnesses, including antidepressants, mood stabilizers, and antipsychotics, are clinically suboptimal. They are effective in only a subset of patients or produce partial responses, and they are often associated with debilitating side effects that discourage adherence. There is growing enthusiasm in the promise of pharmacogenetics to personalize the use of these treatments to maximize their efficacy and tolerability; however, there is still a long way to go before this promise becomes a reality. This article reviews the progress that has been made in research toward understanding how genetic factors influence psychotropic drug responses and the challenges that lie ahead in translating the research findings into clinical practices that yield tangible benefits for patients with mental illnesses.
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Affiliation(s)
- Peter P Zandi
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Hampton House, Room 857, 624 North Broadway, Baltimore, MD 21205, USA.
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90
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Fujita S, Ohnishi T, Okuda S, Kobayashi R, Fukuno S, Furuta D, Kikuchi T, Yoshikawa T, Fujita N. In silico study on the substrate binding manner in human myo-inositol monophosphatase 2. J Mol Model 2011; 17:2559-67. [DOI: 10.1007/s00894-010-0937-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2010] [Accepted: 12/15/2010] [Indexed: 11/29/2022]
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91
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92
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Dixdc1 is a critical regulator of DISC1 and embryonic cortical development. Neuron 2010; 67:33-48. [PMID: 20624590 DOI: 10.1016/j.neuron.2010.06.002] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/20/2010] [Indexed: 01/30/2023]
Abstract
The psychiatric illness risk gene Disrupted in Schizophrenia-1 (DISC1) plays an important role in brain development; however, it is unclear how DISC1 is regulated during cortical development. Here, we report that DISC1 is regulated during embryonic neural progenitor proliferation and neuronal migration through an interaction with DIX domain containing-1 (Dixdc1), the third mammalian gene discovered to contain a Disheveled-Axin (DIX) domain. We determined that Dixdc1 functionally interacts with DISC1 to regulate neural progenitor proliferation by co-modulating Wnt-GSK3beta/beta-catenin signaling. However, DISC1 and Dixdc1 do not regulate migration via this pathway. During neuronal migration, we discovered that phosphorylation of Dixdc1 by cyclin-dependent kinase 5 (Cdk5) facilitates its interaction with the DISC1-binding partner Ndel1. Furthermore, Dixdc1 phosphorylation and its interaction with DISC1/Ndel1 in vivo is required for neuronal migration. Together, these data reveal that Dixdc1 integrates DISC1 into Wnt-GSK3beta/beta-catenin-dependent and -independent signaling pathways during cortical development and further delineate how DISC1 contributes to neuropsychiatric disorders.
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93
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Fayed N, Garcia-Campayo J, Magallón R, Andrés-Bergareche H, Luciano JV, Andres E, Beltrán J. Localized 1H-NMR spectroscopy in patients with fibromyalgia: a controlled study of changes in cerebral glutamate/glutamine, inositol, choline, and N-acetylaspartate. Arthritis Res Ther 2010; 12:R134. [PMID: 20609227 PMCID: PMC2945024 DOI: 10.1186/ar3072] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2010] [Revised: 05/10/2010] [Accepted: 07/07/2010] [Indexed: 12/24/2022] Open
Abstract
INTRODUCTION The purpose of this study was to investigate whether single-voxel (SV) proton magnetic resonance spectroscopy (MRS), diffusion-weighted imaging (DWI), and diffusion tensor imaging (DTI) detected differences between fibromyalgia (FM) patients and healthy controls. We also searched for correlations between neuroimaging abnormalities and neuropsychological variables. METHODS Ten patients with FM and 10 gender- and age-matched control subjects were studied. A neuropsychological examination, DWI, DTI, and proton MRS were performed on the brain areas known to be associated with pain processing. RESULTS Compared with healthy controls, FM patients had significantly higher levels of glutamate + glutamine (Glx) (mean ± SD, 10.71 ± 0.50 arbitrary institutional units versus 9.89 ± 1.04; P = 0.049) and higher glutamate + glutamine/creatine (Glx/Cr) ratios (1.90 ± 0.12 versus 1.72 ± 0.23; P = 0.034) in the posterior gyrus. Myoinositol (Ins) levels of the right and left hippocampi were significantly lower in FM patients (4.49 ± 0.74 versus 5.17 ± 0.62; P = 0.008 and 4.91 ± 0.85 versus 6.09 ± 0.78; P = 0.004, respectively). In FM patients, decreased myoinositol/creatine (Ins/Cr) ratios were found in the left sensorimotor area (P = 0.05) and the left hippocampus (P = 0.002) and lower levels of choline (P = 0.019) and N-acetyl aspartate + N-acetyl aspartyl glutamate (NAA + NAG) (P = 0.034) in the left hippocampus. Significant correlations between depression, pain, and global function and the posterior gyrus Glx levels and Glx/Cr ratios were observed. CONCLUSIONS Glx within the posterior gyrus could be a pathologic factor in FM. Hippocampal dysfunction may be partially responsible for the depressive symptoms of FM. Additional studies with larger samples are required to confirm these preliminary data.
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Affiliation(s)
- Nicolas Fayed
- Department of Radiology, Hospital Quirón, Paseo de Mariano Renovales, Zaragoza, Spain.
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94
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Abstract
Existing psychotropic medications for the treatment of mental illnesses, including antidepressants, mood stabilizers, and antipsychotics, are clinically suboptimal. They are effective in only a subset of patients or produce partial responses, and they are often associated with debilitating side effects that discourage adherence. There is growing enthusiasm in the promise of pharmacogenetics to personalize the use of these treatments to maximize their efficacy and tolerability; however, there is still a long way to go before this promise becomes a reality. This article reviews the progress that has been made in research toward understanding how genetic factors influence psychotropic drug responses and the challenges that lie ahead in translating the research findings into clinical practices that yield tangible benefits for patients with mental illnesses.
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Affiliation(s)
- Peter P Zandi
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Hampton House, Baltimore, MD 21205, USA.
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95
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Ohnishi T, Watanabe A, Ohba H, Iwayama Y, Maekawa M, Yoshikawa T. Behavioral analyses of transgenic mice harboring bipolar disorder candidate genes, IMPA1 and IMPA2. Neurosci Res 2010; 67:86-94. [PMID: 20153384 DOI: 10.1016/j.neures.2010.02.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2009] [Revised: 02/02/2010] [Accepted: 02/03/2010] [Indexed: 12/01/2022]
Abstract
The inositol depletion hypothesis proposes the inhibition of IMPase (myo-inositol monophosphatase) by lithium, a mood stabilizer, as a mechanism of lithium's efficacy. This hypothesis predicts that the upregulation of this biochemical pathway may underlie the pathophysiology of bipolar disorder. In favor of this idea, IMPA2 encoding IMPase is a candidate susceptibility gene for bipolar disorder and that the risk-conferring single nucleotide polymorphisms enhance the promoter activity of IMPA2. However, it is yet unknown whether such upregulation has a biological role in bipolar disorder. To address this issue, we generated transgenic mice for the two IMPase genes (IMPA1 and IMPA2). The expression levels of the transgene were robust in IMPA2 Tg lines, but moderate in IMPA1 Tg lines, when compared to those of endogenous proteins. The transgenic mice behaved normally under drug-naïve conditions, and did not exhibit signs for manic change when an antidepressant amitriptyline was administrated. Interestingly, the male transgenic mice for IMPA2 exhibited a lithium-resistant phenotype in the forced swim test. The current study, as a whole, did not support a substantial role of the upregulation of IMPase in bipolar disorder, although the lithium-insensitivity trait seen in IMPA2 transgenic mice might represent some aspect relevant to the inositol depletion hypothesis.
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Affiliation(s)
- Tetsuo Ohnishi
- Laboratory for Molecular Psychiatry, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
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96
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Thiselton D, Maher B, Webb B, Bigdeli T, O’Neill F, Walsh D, Kendler K, Riley B. Association analysis of the PIP4K2A gene on chromosome 10p12 and schizophrenia in the Irish study of high density schizophrenia families (ISHDSF) and the Irish case-control study of schizophrenia (ICCSS). Am J Med Genet B Neuropsychiatr Genet 2010; 153B:323-31. [PMID: 19475563 PMCID: PMC4011176 DOI: 10.1002/ajmg.b.30982] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Molecular studies support pharmacological evidence that phosphoinositide signaling is perturbed in schizophrenia and bipolar disorder. The phosphatidylinositol-4-phosphate-5-kinase type-II alpha (PIP4K2A) gene is located on chromosome 10p12. This region has been implicated in both diseases by linkage, and PIP4K2A directly by association. Given linkage evidence in the Irish Study of High Density Schizophrenia Families (ISHDSF) to a region including 10p12, we performed an association study between genetic variants at PIP4K2A and disease. No association was detected through single-marker or haplotype analysis of the whole sample. However, stratification into families positive and negative for the ISHDSF schizophrenia high-risk haplotype (HRH) in the DTNBP1 gene and re-analysis for linkage showed reduced amplitude of the 10p12 linkage peak in the DTNBP1 HRH positive families. Association analysis of the stratified sample showed a trend toward association of PIP4K2A SNPs rs1417374 and rs1409395 with schizophrenia in the DTNBP1 HRH positive families. Despite this apparent paradox, our data may therefore suggest involvement of PIP4K2A in schizophrenia in those families for whom genetic variation in DTNBP1 appears also to be a risk factor. This trend appears to arise from under-transmission of common alleles to female cases. Follow-up association analysis in a large Irish schizophrenia case-control sample (ICCSS) showed significant association with disease of a haplotype comprising these same SNPs rs1417374-rs1409395, again more so in affected females, and in cases with negative family history of the disease. This study supports a minor role for PIP4K2A in schizophrenia etiology in the Irish population.
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Affiliation(s)
- D.L. Thiselton
- Department of Psychiatry, Virginia Commonwealth University, Richmond, Virginia,Correspondence to D.L. Thiselton, Virginia Institute of Psychiatric and Behavioural Genetics, Virginia Commonwealth University, Biotech 1/Suite 110, 800 East Leigh Street, Richmond, VA 23298-0424
| | - B.S. Maher
- Department of Psychiatry, Virginia Commonwealth University, Richmond, Virginia
| | - B.T. Webb
- Center for Biomarker Research and Personalized Medicine, Department of Pharmacy, Virginia Commonwealth University, Richmond, Virginia
| | - T.B. Bigdeli
- Department of Human Genetics, Virginia Commonwealth University, Richmond, Virginia
| | - F.A. O’Neill
- Department of Psychiatry, The Queens University, Belfast, Ireland
| | - D. Walsh
- The Health Research Board, Dublin, Ireland
| | - K.S. Kendler
- Department of Psychiatry, Virginia Commonwealth University, Richmond, Virginia
| | - B.P. Riley
- Department of Psychiatry, Virginia Commonwealth University, Richmond, Virginia,Department of Human Genetics, Virginia Commonwealth University, Richmond, Virginia
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97
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Knockout mice in understanding the mechanism of action of lithium. Biochem Soc Trans 2009; 37:1121-5. [PMID: 19754464 DOI: 10.1042/bst0371121] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Lithium inhibits IMPase (inositol monophosphatase) activity, as well as inositol transporter function. To determine whether one or more of these mechanisms might underlie lithium's behavioural effects, we studied Impa1 (encoding IMPase) and Smit1 (sodium-myo-inositol transporter 1)-knockout mice. In brains of adult homozygous Impa1-knockout mice, IMPase activity was found to be decreased; however, inositol levels were not found to be altered. Behavioural analysis indicated decreased immobility in the forced-swim test as well as a strongly increased sensitivity to pilocarpine-induced seizures. These are behaviours robustly induced by lithium. In homozygous Smit1-knockout mice, free inositol levels were decreased in the frontal cortex and hippocampus. These animals behave like lithium-treated animals in the model of pilocarpine seizures and in the Porsolt forced-swim test model of depression. In contrast with O'Brien et al. [O'Brien, Harper, Jove, Woodgett, Maretto, Piccolo and Klein (2004) J. Neurosci. 24, 6791-6798], we could not confirm that heterozygous Gsk3b (glycogen synthase kinase 3beta)-knockout mice exhibit decreased immobility in the Porsolt forced-swim test or decreased amphetamine-induced hyperactivity in a manner mimicking lithium's behavioural effects. These data support the role of inositol-related processes rather than GSK3beta in the mechanism of the therapeutic action of lithium.
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98
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Barker CJ, Illies C, Gaboardi GC, Berggren PO. Inositol pyrophosphates: structure, enzymology and function. Cell Mol Life Sci 2009; 66:3851-71. [PMID: 19714294 PMCID: PMC11115731 DOI: 10.1007/s00018-009-0115-2] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Revised: 07/13/2009] [Accepted: 07/20/2009] [Indexed: 02/04/2023]
Abstract
The stereochemistry of the inositol backbone provides a platform on which to generate a vast array of distinct molecular motifs that are used to convey information both in signal transduction and many other critical areas of cell biology. Diphosphoinositol phosphates, or inositol pyrophosphates, are the most recently characterized members of the inositide family. They represent a new frontier with both novel targets within the cell and novel modes of action. This includes the proposed pyrophosphorylation of a unique subset of proteins. We review recent insights into the structures of these molecules and the properties of the enzymes which regulate their concentration. These enzymes also act independently of their catalytic activity via protein-protein interactions. This unique combination of enzymes and products has an important role in diverse cellular processes including vesicle trafficking, endo- and exocytosis, apoptosis, telomere length regulation, chromatin hyperrecombination, the response to osmotic stress, and elements of nucleolar function.
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Affiliation(s)
- Christopher John Barker
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, 171 76 Stockholm, Sweden
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99
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Calderó J, Brunet N, Tarabal O, Piedrafita L, Hereu M, Ayala V, Esquerda JE. Lithium prevents excitotoxic cell death of motoneurons in organotypic slice cultures of spinal cord. Neuroscience 2009; 165:1353-69. [PMID: 19932742 DOI: 10.1016/j.neuroscience.2009.11.034] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2009] [Revised: 11/12/2009] [Accepted: 11/13/2009] [Indexed: 12/12/2022]
Abstract
Several studies have reported the neuroprotective effects of lithium (Li) suggesting its potential in the treatment of neurological disorders, among of them amyotrophic lateral sclerosis (ALS). Although the cause of motoneuron (MN) death in ALS remains unknown, there is evidence that glutamate-mediated excitotoxicity plays an important role. In the present study we used an organotypic culture system of chick embryo spinal cord to explore the presumptive neuroprotective effects of Li against kainate-induced excitotoxic MN death. We found that chronic treatment with Li prevented excitotoxic MN loss in a dose dependent manner and that this effect was mediated by the inhibition of glycogen synthase kinase-3beta (GSK-3beta) signaling pathway. This neuroprotective effect of Li was potentiated by a combined treatment with riluzole. Nevertheless, MNs rescued by Li displayed structural changes including accumulation of neurofilaments, disruption of the rough endoplasmic reticulum and free ribosome loss, and accumulation of large dense core vesicles and autophagic vacuoles. Accompanying these changes there was an increase in immunostaining for (a) phosphorylated neurofilaments, (b) calcitonin gene-related peptide (CGRP) and (c) the autophagic marker LC3. Chronic Li treatment also resulted in a reduction in the excitotoxin-induced rise in intracellular Ca(2+) in MNs. In contrast to the neuroprotection against excitotoxicity, Li was not able to prevent normal programmed (apoptotic) MN death in the chick embryo when chronically administered in ovo. In conclusion, these results show that although Li is able to prevent excitotoxic MN death by targeting GSK-3beta, this neuroprotective effect is associated with conspicuous cytopathological changes.
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Affiliation(s)
- J Calderó
- Unitat de Neurobiologia Cel.lular, Departament de Medicina Experimental, Facultat de Medicina, Universitat de Lleida and Institut de Recerca Biomèdica de Lleida (IRBLLEIDA), C. Montserrat Roig 2, Catalonia, Spain.
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100
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Amygdala volume in depressed patients with bipolar disorder assessed using high resolution 3T MRI: the impact of medication. Neuroimage 2009; 49:2966-76. [PMID: 19931399 DOI: 10.1016/j.neuroimage.2009.11.025] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2009] [Revised: 11/06/2009] [Accepted: 11/11/2009] [Indexed: 12/24/2022] Open
Abstract
MRI-based reports of both abnormally increased and decreased amygdala volume in bipolar disorder (BD) have surfaced in the literature. Two major methodological weaknesses characterizing extant studies are treatment with medication and inaccurate segmentation of the amygdala due to limitations in spatial and tissue contrast resolution. Here, we acquired high-resolution images (voxel size=0.55 x 0.55 x 0.60 mm) using a GE 3T MRI scanner, and a pulse sequence optimized for tissue contrast resolution. The amygdala was manually segmented by one rater blind to diagnosis, using coronal images. Eighteen unmedicated (mean medication-free period 11+/-10 months) BD subjects were age and gender matched with 18 healthy controls, and 17 medicated (lithium or divalproex) subjects were matched to 17 different controls. The unmedicated BD patients displayed smaller left and right amygdala volumes than their matched control group (p<0.01). Conversely, the BD subjects undergoing medication treatment showed a trend towards greater amygdala volumes than their matched HC sample (p=0.051). Right and left amygdala volumes were larger (p<0.05) or trended larger, respectively, in the medicated BD sample compared with the unmedicated BD sample. The two control groups did not differ from each other in either left or right amygdala volume. BD patients treated with lithium have displayed increased gray matter volume of the cortex and hippocampus relative to untreated BD subjects in previous studies. Here we extend these results to the amygdala. We raise the possibility that neuroplastic changes in the amygdala associated with BD are moderated by some mood stabilizing medications.
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