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Moreland RT, Zhang S, Barreira SN, Ryan JF, Baxevanis AD. An AI-generated proteome-scale dataset of predicted protein structures for the ctenophore Mnemiopsis leidyi. Proteomics 2024; 24:e2300397. [PMID: 38329168 PMCID: PMC11296891 DOI: 10.1002/pmic.202300397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 01/11/2024] [Accepted: 01/12/2024] [Indexed: 02/09/2024]
Abstract
This Dataset Brief describes the computational prediction of protein structures for the ctenophore Mnemiopsis leidyi. Here, we report the proteome-scale generation of 15,333 protein structure predictions using AlphaFold, as well as an updated implementation of publicly available search, manipulation, and visualization tools for these protein structure predictions through the Mnemiopsis Genome Project Portal (https://research.nhgri.nih.gov/mnemiopsis). The utility of these predictions is demonstrated by highlighting comparisons to experimentally determined structures for the light-sensitive protein mnemiopsin 1 and the ionotropic glutamate receptor (iGluR). The application of these novel protein structure prediction methods will serve to further position non-bilaterian species such as Mnemiopsis as powerful model systems for the study of early animal evolution and human health.
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Affiliation(s)
- R. Travis Moreland
- Center for Genomics and Data Science Research, Division of Intramural Research, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, U.S.A
| | - Suiyuan Zhang
- Center for Genomics and Data Science Research, Division of Intramural Research, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, U.S.A
| | - Sofia N. Barreira
- Center for Genomics and Data Science Research, Division of Intramural Research, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, U.S.A
| | - Joseph F. Ryan
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, Florida, U.S.A
| | - Andreas D. Baxevanis
- Center for Genomics and Data Science Research, Division of Intramural Research, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, U.S.A
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2
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Heresco-Levy U, Lerer B. Synergistic psychedelic - NMDAR modulator treatment for neuropsychiatric disorders. Mol Psychiatry 2024; 29:146-152. [PMID: 37945694 DOI: 10.1038/s41380-023-02312-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Revised: 10/17/2023] [Accepted: 10/23/2023] [Indexed: 11/12/2023]
Abstract
Modern research data suggest a therapeutic role for serotonergic psychedelics in depression and other neuropsychiatric disorders, although psychotomimetic effects may limit their widespread utilization. Serotonergic psychedelics enhance neuroplasticity via serotonin 2 A receptors (5HT2AR) activation and complex serotonergic-glutamatergic interactions involving the ionotropic glutamate receptors, tropomyosin receptor kinase B (TrkB) and the mammalian target of rapamycin (mTOR). N-methyl-d-aspartate receptors (NMDAR) channel antagonists, i.e. ketamine, and glycine modulatory site full and partial agonists, i.e., D-serine (DSR) and D-cycloserine (DCS), share some of these mechanisms of action and have neuroplastic and antidepressant effects. Moreover, procognitive effects have been reported for DSR and DCS and 5HT2AR-NMDAR interactions modulate neuronal excitability in prefrontal cortex and represent a target for new antipsychotics. We hypothesize that the synchronous administration of a psychedelic and a NMDAR modulator may increase the therapeutic impact of each of the treatment components and allow for dose adjustments and improved safety. We propose to initially focus research on the acute concurrent administration of psilocybin and DSR or DCS in depression.
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Affiliation(s)
- Uriel Heresco-Levy
- Department of Psychiatry, Herzog Medical Center; Hebrew University Faculty of Medicine, Jerusalem, Israel.
| | - Bernard Lerer
- Hadassah BrainLabs, Center for Psychedelic Research, Hadassah Medical Center, Hebrew University, Jerusalem, Israel.
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3
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Flynn LT, Gao WJ. DNA methylation and the opposing NMDAR dysfunction in schizophrenia and major depression disorders: a converging model for the therapeutic effects of psychedelic compounds in the treatment of psychiatric illness. Mol Psychiatry 2023; 28:4553-4567. [PMID: 37679470 PMCID: PMC11034997 DOI: 10.1038/s41380-023-02235-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 08/17/2023] [Accepted: 08/22/2023] [Indexed: 09/09/2023]
Abstract
Psychedelic compounds are being increasingly explored as a potential therapeutic option for treating several psychiatric conditions, despite relatively little being known about their mechanism of action. One such possible mechanism, DNA methylation, is a process of epigenetic regulation that changes gene expression via chemical modification of nitrogenous bases. DNA methylation has been implicated in the pathophysiology of several psychiatric conditions, including schizophrenia (SZ) and major depressive disorder (MDD). In this review, we propose alterations to DNA methylation as a converging model for the therapeutic effects of psychedelic compounds, highlighting the N-methyl D-aspartate receptor (NMDAR), a crucial mediator of synaptic plasticity with known dysfunction in both diseases, as an example and anchoring point. We review the established evidence relating aberrant DNA methylation to NMDAR dysfunction in SZ and MDD and provide a model asserting that psychedelic substances may act through an epigenetic mechanism to provide therapeutic effects in the context of these disorders.
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Affiliation(s)
- L Taylor Flynn
- Department of Neurobiology & Anatomy, Drexel University College of Medicine, Philadelphia, PA, USA
- MD/PhD program, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Wen-Jun Gao
- Department of Neurobiology & Anatomy, Drexel University College of Medicine, Philadelphia, PA, USA.
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Akbar D, Rhee TG, Ceban F, Ho R, Teopiz KM, Cao B, Subramaniapillai M, Kwan ATH, Rosenblat JD, McIntyre RS. Dextromethorphan-Bupropion for the Treatment of Depression: A Systematic Review of Efficacy and Safety in Clinical Trials. CNS Drugs 2023; 37:867-881. [PMID: 37792265 DOI: 10.1007/s40263-023-01032-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/24/2023] [Indexed: 10/05/2023]
Abstract
BACKGROUND A significant proportion of adults with major depressive disorder (MDD) do not respond to treatments which are currently used in clinical practice such as first-generation monoamine-based antidepressants. OBJECTIVES The objective of this systematic review was to assess the efficacy, safety, and mechanisms of action of AXS-05, a combination of the NMDA-receptor antagonist dextromethorphan with bupropion, in adults with MDD. METHODS We searched PubMed, Embase, Google Scholar, and ClinicalTrials.gov for current studies reporting on efficacy and/or safety of AXS-05 in patients with MDD. The search terms included: "AXS-05" OR "dextromethorphan and bupropion" AND "depression". Studies from database inception to January 2023 were evaluated. Risk of bias was assessed using the Cochrane Risk of Bias tool. RESULTS The search yielded 54 studies of which 5 were included. All studies had low risk of bias. Depression severity, measured with the Montgomery-Åsberg Depression Rating Scale (MADRS) significantly decreased as early as 1-week post-treatment from baseline when compared to a placebo-controlled group (LS mean difference 2.2; 95% CI 0.6-3.9; p = 0.007) and at 2 weeks compared to an active control group (LS mean difference 4.7; 95% CI 0.6-8.8; p = 0.024). Treatment efficacy could be maintained for up to 12 months with mean MADRS score reduction of 23 points from baseline. Clinical remission and response rates also improved at week 1 and were maintained for 12 months. The treatment was well-tolerated, with some transient adverse events reported. CONCLUSION Current evidence suggests that the combination of dextromethorphan and bupropion is a well-tolerated, rapid-acting treatment option for adults with MDD. Initial success with AXS-05 supports the mechanistic role of glutamatergeric and sigma 1 signaling in the pathophysiology of MDD.
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Affiliation(s)
- Dania Akbar
- Mood Disorder Psychopharmacology Unit, University Health Network, Toronto, ON, Canada
| | - Taeho Greg Rhee
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
- VA New England Mental Illness, Research, Education and Clinical Center (MIRECC), VA Connecticut Healthcare System, West Haven, CT, USA
- Department of Public Health Sciences, University of Connecticut School of Medicine, Farmington, CT, USA
| | - Felicia Ceban
- Mood Disorder Psychopharmacology Unit, University Health Network, Toronto, ON, Canada
- Brain and Cognition Discovery Foundation (BCDF), 77 Bloor St W Suite 617, Toronto, ON, M5S 1M2, Canada
- Michael G. DeGroote School of Medicine, McMaster University, Hamilton, ON, Canada
| | - Roger Ho
- Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Institute for Health Innovation and Technology (iHealthtech), National University of Singapore, Singapore, Singapore
| | - Kayla M Teopiz
- Brain and Cognition Discovery Foundation (BCDF), 77 Bloor St W Suite 617, Toronto, ON, M5S 1M2, Canada
| | - Bing Cao
- Key Laboratory of Cognition and Personality, Faculty of Psychology, Ministry of Education, Southwest University, Chongqing, 400715, People's Republic of China
| | - Mehala Subramaniapillai
- Brain and Cognition Discovery Foundation (BCDF), 77 Bloor St W Suite 617, Toronto, ON, M5S 1M2, Canada
| | - Angela T H Kwan
- Mood Disorder Psychopharmacology Unit, University Health Network, Toronto, ON, Canada
- Brain and Cognition Discovery Foundation (BCDF), 77 Bloor St W Suite 617, Toronto, ON, M5S 1M2, Canada
- Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Joshua D Rosenblat
- Mood Disorder Psychopharmacology Unit, University Health Network, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Roger S McIntyre
- Brain and Cognition Discovery Foundation (BCDF), 77 Bloor St W Suite 617, Toronto, ON, M5S 1M2, Canada.
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada.
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada.
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Perić I, Lješević M, Beškoski V, Nikolić M, Filipović D. Metabolomic profiling relates tianeptine effectiveness with hippocampal GABA, myo-inositol, cholesterol, and fatty acid metabolism restoration in socially isolated rats. Psychopharmacology (Berl) 2022; 239:2955-2974. [PMID: 35776189 DOI: 10.1007/s00213-022-06180-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 06/16/2022] [Indexed: 12/28/2022]
Abstract
RATIONALE Discovering biomarkers of major depressive disorder (MDD) can give a deeper understanding of this mood disorder and improve the ability to screen for, diagnose, and treat MDD. OBJECTIVES In this study, metabolomics was used in unraveling metabolite fluctuations of MDD and drug outcome by creating specific metabolomic fingerprints. We report metabolomic patterns of change of the hippocampus of adult male Wistar rats following chronic social isolation (CSIS) (6 weeks), an animal model of depression, and/or chronic tianeptine (Tian) treatment (10 mg kg-1 per day) (lasting 3 weeks of 6-week CSIS), monitored by using comprehensive GC × GC-MS. RESULTS The comparative metabolomic analysis highlighted the role of gamma aminobutyric acid (GABA), iso-allocholate, and unsaturated fatty acid metabolism alterations following the CSIS, which was corroborated with moderate to strong negative Pearson's correlation of GABA, docosahexaenoic, 9-hexadecenoic acid, 5,8,11,14-eicosatetraynoic, and arachidonic acids with immobility behavior in the forced swim test. The antidepressant effect of Tian restored GABA levels, which was absent in Tian resilient rats. Tian decreased myo-inositol and increased TCA cycle intermediates, amino acids, and cholesterol and its metabolite. As key molecules of divergence between Tian effectiveness and resilience, metabolomics revealed myo-inositol, GABA, cholesterol, and its metabolite. A significant moderate positive correlation between myo-inositol and immobility was revealed. Tian probably acted by upregulating NMDAR's and α2 adrenergic receptors (AR) or norepinephrine transporter in both control and stressed animals. CONCLUSION Metabolomics revealed several dysregulations underlying CSIS-induced depressive-like behavior and responsiveness to Tian, predominantly converging into NMDAR-mediated glutamate and myo-inositol signalization and GABA inhibitory pathways.
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Affiliation(s)
- Ivana Perić
- Department of Molecular Biology and Endocrinology, "VINČA" Institute of Nuclear Sciences - National Institute of the Republic of Serbia, University of Belgrade, Mike Petrovića Alasa 12-14, 11351, Vinča, Belgrade, Serbia
| | - Marija Lješević
- Institute of Chemistry, Technology and Metallurgy, University of Belgrade, Njegoševa 12, 11000, Belgrade, Serbia
| | - Vladimir Beškoski
- Department of Biochemistry, University of Belgrade - Faculty of Chemistry, Studentski trg 12-16, 11000, Belgrade, Serbia
| | - Milan Nikolić
- Department of Biochemistry, University of Belgrade - Faculty of Chemistry, Studentski trg 12-16, 11000, Belgrade, Serbia
| | - Dragana Filipović
- Department of Molecular Biology and Endocrinology, "VINČA" Institute of Nuclear Sciences - National Institute of the Republic of Serbia, University of Belgrade, Mike Petrovića Alasa 12-14, 11351, Vinča, Belgrade, Serbia.
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Okada M, Fukuyama K, Motomura E. Dose-Dependent Biphasic Action of Quetiapine on AMPK Signalling via 5-HT7 Receptor: Exploring Pathophysiology of Clinical and Adverse Effects of Quetiapine. Int J Mol Sci 2022; 23:ijms23169103. [PMID: 36012369 PMCID: PMC9409360 DOI: 10.3390/ijms23169103] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 08/05/2022] [Accepted: 08/12/2022] [Indexed: 11/17/2022] Open
Abstract
Recent pharmacological studies indicated that the modulation of tripartite-synaptic transmission plays important roles in the pathophysiology of schizophrenia, mood disorders and adverse reactions. Therefore, to explore the mechanisms underlying the clinical and adverse reactions to atypical antipsychotics, the present study determined the effects of the sub-chronic administration of quetiapine (QTP: 3~30 μM) on the protein expression of 5-HT7 receptor (5-HT7R), connexin43 (Cx43), cAMP level and intracellular signalling, Akt, Erk and adenosine monophosphate-activated protein kinase (AMPK) in cultured astrocytes and the rat hypothalamus, using ultra-high-pressure liquid chromatography with mass spectrometry and capillary immunoblotting systems. QTP biphasically increased physiological ripple-burst evoked astroglial D-serine release in a concentration-dependent manner, peaking at 10 μM. QTP enhanced the astroglial signalling of Erk concentration-dependently, whereas both Akt and AMPK signalling’s were biphasically enhanced by QTP, peaking at 10 μM and 3 μM, respectively. QTP downregulated astroglial 5-HT7R in the plasma membrane concentration-dependently. Protein expression of Cx43 in astroglial cytosol and intracellular cAMP levels were decreased and increased by QTP also biphasically, peaking at 3 μM. The dose-dependent effects of QTP on the protein expression of 5-HT7R and Cx43, AMPK signalling and intracellular cAMP levels in the hypothalamus were similar to those in astrocytes. These results suggest several complicated pharmacological features of QTP. A therapeutically relevant concentration/dose of QTP activates Akt, Erk and AMPK signalling, whereas a higher concentration/dose of QTP suppresses AMPK signalling via its low-affinity 5-HT7R inverse agonistic action. Therefore, 5-HT7R inverse agonistic action probably plays important roles in the prevention of a part of adverse reactions of QTP, such as weight gain and metabolic complications.
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7
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Steiner J, Dobrowolny H, Guest PC, Bernstein HG, Fuchs D, Roeser J, Summergrad P, Oxenkrug GF. Plasma Anthranilic Acid and Leptin Levels Predict HAM-D Scores in Depressed Women. Int J Tryptophan Res 2021; 14:11786469211016474. [PMID: 34045868 PMCID: PMC8138296 DOI: 10.1177/11786469211016474] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 04/18/2021] [Indexed: 11/24/2022] Open
Abstract
Objectives: Major depressive disorder (MDD) is associated with dysregulations of leptin
and tryptophan–kynurenine (Trp–Kyn) (TKP) pathways. Leptin, a
pro-inflammatory cytokine, activates Trp conversion into Kyn. However,
leptin association with down-stream Kyn metabolites in MDD is unknown. Methods: Fasting plasma samples from 29 acutely ill drug-naïve (n = 16) or currently
non-medicated (⩾6 weeks; n = 13) MDD patients were analyzed for leptin, Trp,
Kyn, its down-stream metabolites (anthranilic [AA], kynurenic [KYNA],
xanthurenic [XA] acids and 3-hydroxykynurenine [3HK]), C-reactive protein
(CRP), neopterin, body mass index (BMI), and insulin resistance (HOMA-IR).
Depression severity was assessed by HAM-D-21. Results: In female (n = 14) (but not in male) patients HAM-D-21 scores correlated with
plasma levels of AA (but not other Kyn metabolites) (rho = −0.644,
P = .009) and leptin (Spearman’s rho = −0.775,
P = .001). Inclusion of AA into regression analysis
improved leptin prediction of HAM-D from 48.5% to 65.9%. Actual HAM-D scores
highly correlated with that calculated by formula: HAM-D = 34.8518−(0.5660 ×
leptin [ng/ml] + 0.4159 × AA [nmol/l]) (Rho = 0.84, P =
.00015). In male (n = 15) (but not in female) patients leptin correlated
with BMI, waist circumference/hip ratio, CRP, and HOMA-IR. Conclusions: Present findings of gender specific AA/Leptin correlations with HAM-D are
important considering that AA and leptin are transported from plasma into
brain, and that AA formation is catalyzed by
kynureninase—the only TKP gene associated with depression
according to genome-wide analysis. High correlation between predicted and
actual HAM-D warrants further evaluation of plasma AA and leptin as an
objective laboratory test for the assessment of depression severity in
female MDD patients
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Affiliation(s)
- Johann Steiner
- Laboratory of Translational Psychiatry, University of Magdeburg, Magdeburg, Saxony-Anhalt, Germany.,Department of Psychiatry and Psychotherapy, University of Magdeburg, Magdeburg, Germany.,Center for Behavioral Brain Sciences, Magdeburg, Germany
| | - Henrik Dobrowolny
- Laboratory of Translational Psychiatry, University of Magdeburg, Magdeburg, Saxony-Anhalt, Germany.,Department of Psychiatry and Psychotherapy, University of Magdeburg, Magdeburg, Germany
| | - Paul C Guest
- Laboratory of Neuroproteomics, Department of Biochemistry and Tissue Biology, University of Campinas, Campinas, Brazil
| | - Hans-Gert Bernstein
- Laboratory of Translational Psychiatry, University of Magdeburg, Magdeburg, Saxony-Anhalt, Germany.,Department of Psychiatry and Psychotherapy, University of Magdeburg, Magdeburg, Germany
| | - Dietmar Fuchs
- Institute of Biological Chemistry, Biocenter of the Medical University of Innsbruck, Innsbruck, Tyrol, Austria
| | - Julien Roeser
- Charles River Laboratories, South San Francisco, CA, USA
| | - Paul Summergrad
- Department of Psychiatry, Psychiatry and Inflammation Program, Tufts University School of Medicine, Boston, MA, USA
| | - Gregory F Oxenkrug
- Department of Psychiatry, Psychiatry and Inflammation Program, Tufts University School of Medicine, Boston, MA, USA
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Positive modulation of NMDA receptors by AGN-241751 exerts rapid antidepressant-like effects via excitatory neurons. Neuropsychopharmacology 2021; 46:799-808. [PMID: 33059355 PMCID: PMC8027594 DOI: 10.1038/s41386-020-00882-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 09/03/2020] [Accepted: 09/29/2020] [Indexed: 12/25/2022]
Abstract
Dysregulation of the glutamatergic system and its receptors in medial prefrontal cortex (mPFC) has been implicated in major depressive disorder. Recent preclinical studies have shown that enhancing NMDA receptor (NMDAR) activity can exert rapid antidepressant-like effects. AGN-241751, an NMDAR positive allosteric modulator (PAM), is currently being tested as an antidepressant in clinical trials, but the mechanism and NMDAR subunit(s) mediating its antidepressant-like effects are unknown. We therefore used molecular, biochemical, and electrophysiological approaches to examine the cell-type-specific role of GluN2B-containing NMDAR in mediating antidepressant-like behavioral effects of AGN-241751. We demonstrate that AGN-241751 exerts antidepressant-like effects and reverses behavioral deficits induced by chronic unpredictable stress in mice. AGN-241751 treatment enhances NMDAR activity of excitatory and parvalbumin-inhibitory neurons in mPFC, activates Akt/mTOR signaling, and increases levels of synaptic proteins crucial for synaptic plasticity in the prefrontal cortex. Furthermore, cell-type-specific knockdown of GluN2B-containing NMDARs in mPFC demonstrates that GluN2B subunits on excitatory, but not inhibitory, neurons are necessary for antidepressant-like effects of AGN-241751. Together, these results demonstrate antidepressant-like actions of the NMDAR PAM AGN-241751 and identify GluN2B on excitatory neurons of mPFC as initial cellular trigger underlying these behavioral effects.
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Post-inflammatory behavioural despair in male mice is associated with reduced cortical glutamate-glutamine ratios, and circulating lipid and energy metabolites. Sci Rep 2020; 10:16857. [PMID: 33033375 PMCID: PMC7545201 DOI: 10.1038/s41598-020-74008-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 09/10/2020] [Indexed: 12/13/2022] Open
Abstract
Post-inflammatory behaviours in rodents are widely used to model human depression and to test the efficacy of novel anti-depressants. Mice injected with lipopolysaccharide (LPS) display a depressive-like phenotype twenty-four hours after endotoxin administration. Despite the widespread use of this model, the mechanisms that underlie the persistent behavioural changes after the transient peripheral inflammatory response remain elusive. The study of the metabolome, the collection of all the small molecule metabolites in a sample, combined with multivariate statistical techniques provides a way of studying biochemical pathways influenced by an LPS challenge. Adult male CD-1 mice received an intraperitoneal injection of either LPS (0.83 mg/kg) or saline, and were assessed for depressive-like behaviour 24 h later. In a separate mouse cohort, pro-inflammatory cytokine gene expression and 1H nuclear magnetic resonance (NMR) metabolomics measurements were made in brain tissue and blood. Statistical analyses included Independent Sample t-tests for gene expression data, and supervised multi-variate analysis using orthogonal partial least squares discriminant analysis for metabolomics. Both plasma and brain metabolites in male mice were altered following a single peripheral LPS challenge that led to depressive-like behaviour in the forced swim test. The plasma metabolites altered by LPS are involved in energy metabolism, including lipoproteins, glucose, creatine, and isoleucine. In the brain, glutamate, serine, and N-acetylaspartate (NAA) were reduced after LPS, whereas glutamine was increased. Serine-modulated glutamatergic signalling and changes in bioenergetics may mediate the behavioural phenotype induced by LPS. In light of other data supporting a central imbalance of glutamate-glutamine cycling in depression, our results suggest that aberrant central glutaminergic signalling may underpin the depressive-like behaviours that result from both inflammation and non-immune pathophysiology. Normalising glutaminergic signalling, rather than seeking to increase serotonergic signalling, might prove to be a more coherent approach to the development of new treatments for mood disorder.
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10
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Nowacki J, Wingenfeld K, Kaczmarczyk M, Chae WR, Salchow P, Abu-Tir I, Piber D, Hellmann-Regen J, Otte C. Steroid hormone secretion after stimulation of mineralocorticoid and NMDA receptors and cardiovascular risk in patients with depression. Transl Psychiatry 2020; 10:109. [PMID: 32313032 PMCID: PMC7171120 DOI: 10.1038/s41398-020-0789-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 03/12/2020] [Accepted: 03/25/2020] [Indexed: 12/14/2022] Open
Abstract
Major depressive disorder (MDD) is associated with altered mineralocorticoid receptor (MR) and glucocorticoid receptor function, and disturbed glutamatergic signaling. Both systems are closely intertwined and likely contribute not only to the pathophysiology of MDD, but also to the increased cardiovascular risk in MDD patients. Less is known about other steroid hormones, such as aldosterone and DHEA-S, and how they affect the glutamatergic system and cardiovascular disease risk in MDD. We examined salivary cortisol, aldosterone, and DHEA-S secretion after stimulation of MR and glutamatergic NMDA receptors in 116 unmedicated depressed patients, and 116 age- and sex-matched healthy controls. Patients (mean age = 34.7 years, SD = ±13.3; 78% women) and controls were randomized to four conditions: (a) control condition (placebo), (b) MR stimulation (0.4 mg fludrocortisone), (c) NMDA stimulation (250 mg D-cycloserine (DCS)), and (d) combined MR/NMDA stimulation (fludrocortisone + DCS). We additionally determined the cardiovascular risk profile in both groups. DCS had no effect on steroid hormone secretion, while cortisol secretion decreased in both fludrocortisone conditions across groups. Independent of condition, MDD patients showed (1) increased cortisol, increased aldosterone, and decreased DHEA-S concentrations, and (2) increased glucose levels and decreased high-density lipoprotein cholesterol levels compared with controls. Depressed patients show profound alterations in several steroid hormone systems that are associated both with MDD pathophysiology and increased cardiovascular risk. Prospective studies should examine whether modulating steroid hormone levels might reduce psychopathology and cardiovascular risk in depressed patients.
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Affiliation(s)
- Jan Nowacki
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany.
| | - Katja Wingenfeld
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Michael Kaczmarczyk
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Woo Ri Chae
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Paula Salchow
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Ikram Abu-Tir
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Dominique Piber
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Julian Hellmann-Regen
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Christian Otte
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany
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11
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Steelman BC. A pivot from synaptic monoamine processes to further downstream processes: The impact of ketamine research. Perspect Psychiatr Care 2019; 55:190-193. [PMID: 30040131 DOI: 10.1111/ppc.12317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 06/20/2018] [Accepted: 07/03/2018] [Indexed: 11/30/2022] Open
Abstract
PURPOSE Currently only one-third of patients treated for depression enjoy complete remission of their negative symptoms. This paper explores ketamine research as it applies to understanding and treating mood illnesses. CONCLUSIONS Ketamine's rapid antidepressant effect implicates downstream signal transduction involving the spontaneous transmissions associated with ketamine's action at the NMDA receptor. PRACTICE IMPLICATIONS Better understanding of brain neuropathophysiology offers hope for symptom relief to those living with affective illness refractory to currently available medical management.
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MacKay MAB, Kravtsenyuk M, Thomas R, Mitchell ND, Dursun SM, Baker GB. D-Serine: Potential Therapeutic Agent and/or Biomarker in Schizophrenia and Depression? Front Psychiatry 2019; 10:25. [PMID: 30787885 PMCID: PMC6372501 DOI: 10.3389/fpsyt.2019.00025] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Accepted: 01/15/2019] [Indexed: 11/17/2022] Open
Abstract
D-Serine is a potent co-agonist at the NMDA glutamate receptor and has been the object of many preclinical studies to ascertain the nature of its metabolism, its regional and cellular distribution in the brain, its physiological functions and its possible clinical relevance. The enzymes involved in its formation and catabolism are serine racemase (SR) and D-amino acid oxidase (DAAO), respectively, and manipulations of the activity of those enzymes have been useful in developing animal models of schizophrenia and in providing clues to the development of potential new antipsychotic strategies. Clinical studies have been conducted in schizophrenia patients to evaluate body fluid levels of D-serine and/or to use D-serine alone or in combination with antipsychotics to determine its effectiveness as a therapeutic agent. D-serine has also been used in combination with DAAO inhibitors in preclinical investigations, and interesting results have been obtained. Genetic studies and postmortem brain studies have also been conducted on D-serine and the enzymes involved in its metabolism. It is also of considerable interest that in recent years clinical and preclinical investigations have suggested that D-serine may also have antidepressant properties. Clinical studies have also shown that D-serine may be a biomarker for antidepressant response to ketamine. Relevant to both schizophrenia and depression, preclinical and clinical studies with D-serine indicate that it may be effective in reducing cognitive dysfunction.
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Affiliation(s)
- Mary-Anne B MacKay
- Neurochemical Research Unit and Bebensee Schizophrenia Research Unit, Department of Psychiatry, University of Alberta, Edmonton, AB, Canada.,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Maryana Kravtsenyuk
- Neurochemical Research Unit and Bebensee Schizophrenia Research Unit, Department of Psychiatry, University of Alberta, Edmonton, AB, Canada.,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Rejish Thomas
- Neurochemical Research Unit and Bebensee Schizophrenia Research Unit, Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
| | - Nicholas D Mitchell
- Neurochemical Research Unit and Bebensee Schizophrenia Research Unit, Department of Psychiatry, University of Alberta, Edmonton, AB, Canada.,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Serdar M Dursun
- Neurochemical Research Unit and Bebensee Schizophrenia Research Unit, Department of Psychiatry, University of Alberta, Edmonton, AB, Canada.,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Glen B Baker
- Neurochemical Research Unit and Bebensee Schizophrenia Research Unit, Department of Psychiatry, University of Alberta, Edmonton, AB, Canada.,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
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Zhang J, Chen Y, Luo H, Sun L, Xu M, Yu J, Zhou Q, Meng G, Yang S. Recent Update on the Pharmacological Effects and Mechanisms of Dihydromyricetin. Front Pharmacol 2018; 9:1204. [PMID: 30410442 PMCID: PMC6209623 DOI: 10.3389/fphar.2018.01204] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 10/02/2018] [Indexed: 12/19/2022] Open
Abstract
As the most abundant natural flavonoid in rattan tea, dihydromyricetin (DMY) has shown a wide range of pharmacological effects. In addition to the general characteristics of flavonoids, DMY has the effects of cardioprotection, anti-diabetes, hepatoprotection, neuroprotection, anti-tumor, and dermatoprotection. DMY was also applied for the treatment of bacterial infection, osteoporosis, asthma, kidney injury, nephrotoxicity and so on. These effects to some extent enrich the understanding about the role of DMY in disease prevention and therapy. However, to date, we still have no outlined knowledge about the detailed mechanism of DMY, which might be related to anti-oxidation and anti-inflammation. And the detailed mechanisms may be associated with several different molecules involved in cellular apoptosis, oxidative stress, and inflammation, such as AMP-activated protein kinase (AMPK), mitogen-activated protein kinase (MAPK), protein kinase B (Akt), nuclear factor-κB (NF-κB), nuclear factor E2-related factor 2 (Nrf2), ATP-binding cassette transporter A1 (ABCA1), peroxisome proliferator-activated receptor-γ (PPARγ) and so on. Here, we summarized the current pharmacological developments of DMY as well as possible mechanisms, aiming to push the understanding about the protective role of DMY as well as its preclinical assessment of novel application.
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Affiliation(s)
- Jingyao Zhang
- Department of Dermatology, Affiliated Hospital of Nantong University, Nantong, China.,Department of Pharmacology, School of Pharmacy, Key Laboratory of Inflammation and Molecular Drug Target of Jiangsu Province, Nantong University, Nantong, China
| | - Yun Chen
- Department of Pharmacology, School of Pharmacy, Key Laboratory of Inflammation and Molecular Drug Target of Jiangsu Province, Nantong University, Nantong, China
| | - Huiqin Luo
- Department of Dermatology, Affiliated Hospital of Nantong University, Nantong, China.,Department of Pharmacology, School of Pharmacy, Key Laboratory of Inflammation and Molecular Drug Target of Jiangsu Province, Nantong University, Nantong, China
| | - Linlin Sun
- Department of Dermatology, Affiliated Hospital of Nantong University, Nantong, China.,Department of Pharmacology, School of Pharmacy, Key Laboratory of Inflammation and Molecular Drug Target of Jiangsu Province, Nantong University, Nantong, China
| | - Mengting Xu
- Department of Dermatology, Affiliated Hospital of Nantong University, Nantong, China.,Department of Pharmacology, School of Pharmacy, Key Laboratory of Inflammation and Molecular Drug Target of Jiangsu Province, Nantong University, Nantong, China
| | - Jin Yu
- Department of Pharmacology, School of Pharmacy, Key Laboratory of Inflammation and Molecular Drug Target of Jiangsu Province, Nantong University, Nantong, China
| | - Qigang Zhou
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing, China
| | - Guoliang Meng
- Department of Dermatology, Affiliated Hospital of Nantong University, Nantong, China
| | - Shengju Yang
- Department of Dermatology, Affiliated Hospital of Nantong University, Nantong, China
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Abstract
Ketamine and its enantiomer S-ketamine (esketamine) are promising candidates to produce a rapid-onset antidepressant effect in treatment-resistant depression. Ketamine causes continued blockade of the glutamate N-methyl-D-aspartate (NMDA) receptor, though this might not primarily mediate the antidepressant effect. Alternative hypotheses include selectivity for the NMDA receptor subtype containing the NMDA receptor subunit 2B (NR2B), inhibition of the phosphorylation of the eukaryotic elongation factor 2 (eEF2) kinase, increased expression of brain-derived neurotrophic factor (BDNF) and tropomyosin receptor kinase B (TrKB), and activation of the mammalian target of rapamycin (mTOR) signaling pathway, alongside other independent actions attributed to the ketamine metabolism to R-hydroxynorketamine (R-HNK). The enantiomer S-ketamine (esketamine) displays approximately fourfold greater affinity for the glutamate NMDA receptor in vitro than R-ketamine. Proof-of-concept single-dose and repeat-dose studies with intravenous ketamine show a significant antidepressant and probably antisuicidal effect in the short term, with response rates over 60% as early as 4.5 h after a single dose, with a sustained effect after 24 h, and over 40% after 7 days. This response can be further sustained over several weeks with repeated doses (two to three doses per week). Tolerability seems acceptable in the short term, with transient elevation of blood pressure and mild and transient dissociative and psychotomimetic effects. Intranasal esketamine has shown a comparable antidepressant effect, which has resulted in the US FDA granting the drug a "breakthrough therapy" designation, and theoretically it may offer an improved tolerability profile. However, major concerns remain regarding an effective protocol to maintain the clinical antidepressant effect of ketamine seen with acute administration and the safety of ketamine and esketamine in the long term, specifically related to potential neurocognitive and urologic toxicity, together with the potential induction of substance use disorders. Ketamine and esketamine are not currently approved treatments for depression, but the clinical use of ketamine is increasing in a variety of practice settings internationally.
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Guercio GD, Panizzutti R. Potential and Challenges for the Clinical Use of d-Serine As a Cognitive Enhancer. Front Psychiatry 2018; 9:14. [PMID: 29459833 PMCID: PMC5807334 DOI: 10.3389/fpsyt.2018.00014] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 01/17/2018] [Indexed: 12/16/2022] Open
Abstract
After 25 years of its discovery in the rat brain, d-serine is a recognized modulator of synaptic plasticity and cognitive processes through its actions on the NMDA-glutamate receptor. Importantly, cognitive impairment is a core feature of conditions, such as schizophrenia, Alzheimer's disease, depression, and aging, and is associated to disturbances in NMDA-glutamate receptors. The d-serine pathway has been associated with cognitive deficits and these conditions, and, for this reason, d-serine signaling is subject of intense research to probe its role in aiding diagnosis and therapy. Nevertheless, this has not resulted in new therapies being incorporated into clinical practice. Therefore, in this review we will address many questions that need to be solved by future studies, regarding d-serine pharmacokinetics, possible side effects, other strategies to modulate its levels, and combination with other therapies to increase its efficacy.
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Affiliation(s)
- Gerson D. Guercio
- Instituto de Ciencias Biomedicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Rogerio Panizzutti
- Instituto de Ciencias Biomedicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Global Brain Health Institute, Trinity College Dublin, Dublin, Ireland
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Aroniadou-Anderjaska V, Pidoplichko VI, Figueiredo TH, Braga MFM. Oscillatory Synchronous Inhibition in the Basolateral Amygdala and its Primary Dependence on NR2A-containing NMDA Receptors. Neuroscience 2018; 373:145-158. [PMID: 29339324 DOI: 10.1016/j.neuroscience.2018.01.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 12/20/2017] [Accepted: 01/07/2018] [Indexed: 12/18/2022]
Abstract
Synchronous, rhythmic firing of GABAergic interneurons is a fundamental mechanism underlying the generation of brain oscillations, and evidence suggests that NMDA receptors (NMDARs) play a key role in oscillatory activity by regulating the activity of interneurons. Consistent with this, derangement of brain rhythms in certain neuropsychiatric disorders, notably schizophrenia and autism, is associated with NMDAR hypofunction and loss of inhibitory interneurons. In the basolateral amygdala (BLA)-dysfunction of which is involved in a host of neuropsychiatric diseases-, principal neurons display spontaneous, rhythmic "bursts" of inhibitory activity, which could potentially be involved in the orchestration of oscillations in the BLA network; here, we investigated the role of NMDARs in these inhibitory oscillations. Rhythmic bursts of spontaneous IPSCs (0.5 Hz average burst frequency) recorded from rat BLA principal cells were blocked or significantly suppressed by D-AP5, and could be driven by NMDAR activation alone. BLA interneurons generated spontaneous bursts of suprathreshold EPSCs at a similar frequency, which were also blocked or reduced by D-AP5. PEAQX (GluN2A-NMDAR antagonist; 0.4 μM) or Ro-25-6981 (GluN2B-NMDAR antagonist; 5 μM) suppressed the IPSC and EPSC bursts; suppression by PEAQX was significantly greater than that by Ro-25-6981. Immunohistochemical labeling revealed the presence of both GluN2A- and GluN2B-NMDARs on GABAergic BLA interneurons, while, functionally, GluN2A-NMDARs have the dominant role, as suggested by a greater reduction of NMDA-evoked currents by PEAQX versus Ro-25-6981. Entrainment of BLA principal neurons in an oscillatory generation of inhibitory activity depends primarily on activation of GluN2A-NMDARs, and interneuronal GluN2A-NMDARs may play a significant role.
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Affiliation(s)
- Vassiliki Aroniadou-Anderjaska
- Department of Psychiatry, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA; Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA.
| | - Volodymyr I Pidoplichko
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA.
| | - Taiza H Figueiredo
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA.
| | - Maria F M Braga
- Department of Psychiatry, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA; Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA.
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Dihydromyricetin exerts a rapid antidepressant-like effect in association with enhancement of BDNF expression and inhibition of neuroinflammation. Psychopharmacology (Berl) 2018; 235:233-244. [PMID: 29058041 DOI: 10.1007/s00213-017-4761-z] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 10/11/2017] [Indexed: 12/19/2022]
Abstract
RATIONALE Major depressive disorder (MDD) is a highly prevalent illness that affects large populations across the world, and increasing evidence suggests that neuroinflammation and levels of brain-derived neurotrophic factor (BDNF) are closely related to depression. Dihydromyricetin (DHM) is a kind of flavonoid natural product that has been reported to display multiple pharmacological effects, including anti-inflammatory and anti-oxidative properties, and these may contribute to ameliorate MDD. OBJECTIVE This study investigated the effect of DHM on depression-related phenotypes in various experimental animal models. METHODS The antidepressant-like effect of DHM was validated via depression-related behavioral tests in naïve male C57BL/6 mice, as well as in the acute lipopolysaccharide-induced mouse model of depression. The chronic unpredicted mild stress (CUMS) mouse model of depression was also used to assess the rapid antidepressant-like effect of DHM by tail suspension test (TST), forced swimming test (FST), locomotor activity, and sucrose preference test (SPT). The expression of BDNF and inflammatory factors were determined through Western blotting and enzyme-linked immunosorbent assay, respectively. RESULTS DHM reduced immobility time in the TST and FST both in mice and the acute LPS-induced mouse model of depression. Seven days of DHM treatment ameliorated depression-related behaviors induced by CUMS, whereas similar treatment with the typical antidepressant venlafaxine did not. DHM activated the ERK1/2-CREB pathway and increased glycogen synthase kinase-3 beta (GSK-3β) phosphorylation at ser-9, with upregulation of BDNF expression, in both hippocampal tissues and cultured hippocampal cells. CONCLUSION The present data indicate that DHM exerts a more rapid antidepressant-like effect than does a typical antidepressant, in association with enhancement of BDNF expression and inhibition of neuroinflammation.
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Sinitskiy AV, Pande VS. Simulated Dynamics of Glycans on Ligand-Binding Domain of NMDA Receptors Reveals Strong Dynamic Coupling between Glycans and Protein Core. J Chem Theory Comput 2017; 13:5496-5505. [PMID: 29019687 DOI: 10.1021/acs.jctc.7b00817] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
N-Methyl-d-aspartate (NMDA) receptors, key neuronal receptors playing the central role in learning and memory, are heavily glycosylated in vivo. Astonishingly little is known about the structure, dynamics, and physiological relevance of glycans attached to them. We recently demonstrated that certain glycans on the ligand binding domain (LBD) of NMDA receptors (NMDARs) can serve as intramolecular potentiators, changing EC50 of NMDAR coagonists. In this work, we use molecular dynamics trajectories, in aggregate 86.5 μs long, of the glycosylated LBD of the GluN1 subunit of the NMDAR to investigate the behavior of glycans on NMDARs. Though all glycans in our simulations were structurally the same (Man5), the dynamics of glycans at different locations on NMDARs was surprisingly different. The slowest-time scale motions that we detected in various glycans in some cases corresponded to a flipping of parts of glycans relative to each other, while in other cases they reduced to a head-to-tail bending of a glycan. We predict that time scales of conformational changes in glycans on the GluN1 LBD of NMDARs range from nanoseconds to at least hundreds of microseconds. Some of the conformational changes in the glycans correlate with the physiologically important clamshell-like opening and closing of the GluN1 LBD domain. Thus, glycans are an integral part of NMDARs, and computational models of NMDARs should include glycans to faithfully represent the structure and the dynamics of these receptors.
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Affiliation(s)
- Anton V Sinitskiy
- Department of Chemistry, ‡Department of Computer Science, and §Department of Structural Biology, Stanford University , Stanford, California 94305, United States
| | - Vijay S Pande
- Department of Chemistry, ‡Department of Computer Science, and §Department of Structural Biology, Stanford University , Stanford, California 94305, United States
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Wang J, Zhang K, Chen X, Liu X, Teng H, Zhao M, Sun Z. Epigenetic Activation of ASCT2 in the Hippocampus Contributes to Depression-Like Behavior by Regulating D-Serine in Mice. Front Mol Neurosci 2017; 10:139. [PMID: 28536503 PMCID: PMC5422558 DOI: 10.3389/fnmol.2017.00139] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Accepted: 04/21/2017] [Indexed: 11/28/2022] Open
Abstract
The roles of D-serine in depression are raised concerned recently as an intrinsic co-agonist for the NMDA receptor. However, the mechanisms underlying its regulation are not fully elucidated. ASCT2 is a Na+-dependent D-serine transporter. We found that decreased D-serine and increased hippocampal ASCT2 levels correlated with chronic social defeat stress (CSDS) in mice. Lentivirus-mediated shRNA-mediated knockdown of ASCT2 and the administration of exogenous D-serine in the hippocampus alleviated CSDS-induced social avoidance and immobility. In vivo and in vitro experiments revealed that upregulation of ASCT2 expression in CSDS was regulated through histone hyper-acetylation, not DNA methylation in its promoter region. Immunohistochemistry demonstrated the co-localization of ASCT2 and D-serine. Uptake of D-serine by ASCT2 was demonstrated by in vivo and in vitro experiments. Our results indicate that CSDS induces ASCT2 expression through epigenetic activation and decreases hippocampal D-serine levels, leading to social avoidance, and immobility. Thus, targeting D-serine transport represents an attractive new strategy for treating depression.
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Affiliation(s)
- Jiesi Wang
- Beijing Institutes of Life Science, Chinese Academy of SciencesBeijing, China.,Key Lab of Mental Health, Institute of Psychology, Chinese Academy of SciencesBeijing, China.,University of Chinese Academy of SciencesBeijing, China
| | - Ke Zhang
- Key Lab of Mental Health, Institute of Psychology, Chinese Academy of SciencesBeijing, China.,University of Chinese Academy of SciencesBeijing, China
| | - Xiaojuan Chen
- Key Lab of Mental Health, Institute of Psychology, Chinese Academy of SciencesBeijing, China.,University of Chinese Academy of SciencesBeijing, China
| | - Xiaoqian Liu
- Key Lab of Mental Health, Institute of Psychology, Chinese Academy of SciencesBeijing, China
| | - Huajing Teng
- Beijing Institutes of Life Science, Chinese Academy of SciencesBeijing, China
| | - Mei Zhao
- Key Lab of Mental Health, Institute of Psychology, Chinese Academy of SciencesBeijing, China.,University of Chinese Academy of SciencesBeijing, China
| | - Zhongsheng Sun
- Beijing Institutes of Life Science, Chinese Academy of SciencesBeijing, China.,Key Lab of Mental Health, Institute of Psychology, Chinese Academy of SciencesBeijing, China.,Institute of Genomic Medicine, Wenzhou Medical CollegeWenzhou, China
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