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Bharambe N, Li Z, Seiferth D, Balakrishna AM, Biggin PC, Basak S. Cryo-EM structures of prokaryotic ligand-gated ion channel GLIC provide insights into gating in a lipid environment. Nat Commun 2024; 15:2967. [PMID: 38580666 PMCID: PMC10997623 DOI: 10.1038/s41467-024-47370-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 03/28/2024] [Indexed: 04/07/2024] Open
Abstract
GLIC, a proton-activated prokaryotic ligand-gated ion channel, served as a model system for understanding the eukaryotic counterparts due to their structural and functional similarities. Despite extensive studies conducted on GLIC, the molecular mechanism of channel gating in the lipid environment requires further investigation. Here, we present the cryo-EM structures of nanodisc-reconstituted GLIC at neutral and acidic pH in the resolution range of 2.6 - 3.4 Å. In our apo state at pH 7.5, the extracellular domain (ECD) displays conformational variations compared to the existing apo structures. At pH 4.0, three distinct conformational states (C1, C2 and O states) are identified. The protonated structures exhibit a compacted and counter-clockwise rotated ECD compared with our apo state. A gradual widening of the pore in the TMD is observed upon reducing the pH, with the widest pore in O state, accompanied by several layers of water pentagons. The pore radius and molecular dynamics (MD) simulations suggest that the O state represents an open conductive state. We also observe state-dependent interactions between several lipids and proteins that may be involved in the regulation of channel gating. Our results provide comprehensive insights into the importance of lipids impact on gating.
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Affiliation(s)
- Nikhil Bharambe
- School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
| | - Zhuowen Li
- School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
| | - David Seiferth
- Structural Bioinformatics and Computational Biochemistry, Department of Biochemistry, University of Oxford, Oxford, UK
| | | | - Philip C Biggin
- Structural Bioinformatics and Computational Biochemistry, Department of Biochemistry, University of Oxford, Oxford, UK
| | - Sandip Basak
- School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore.
- NTU Institute of Structural Biology, Nanyang Technological University, Singapore, 639798, Singapore.
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2
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Kalinichenko L, Kornhuber J, Sinning S, Haase J, Müller CP. Serotonin Signaling through Lipid Membranes. ACS Chem Neurosci 2024; 15:1298-1320. [PMID: 38499042 PMCID: PMC10995955 DOI: 10.1021/acschemneuro.3c00823] [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: 12/20/2023] [Revised: 02/22/2024] [Accepted: 02/27/2024] [Indexed: 03/20/2024] Open
Abstract
Serotonin (5-HT) is a vital modulatory neurotransmitter responsible for regulating most behaviors in the brain. An inefficient 5-HT synaptic function is often linked to various mental disorders. Primarily, membrane proteins controlling the expression and activity of 5-HT synthesis, storage, release, receptor activation, and inactivation are critical to 5-HT signaling in synaptic and extra-synaptic sites. Moreover, these signals represent information transmission across membranes. Although the lipid membrane environment is often viewed as fairly stable, emerging research suggests significant functional lipid-protein interactions with many synaptic 5-HT proteins. These protein-lipid interactions extend to almost all the primary lipid classes that form the plasma membrane. Collectively, these lipid classes and lipid-protein interactions affect 5-HT synaptic efficacy at the synapse. The highly dynamic lipid composition of synaptic membranes suggests that these lipids and their interactions with proteins may contribute to the plasticity of the 5-HT synapse. Therefore, this broader protein-lipid model of the 5-HT synapse necessitates a reconsideration of 5-HT's role in various associated mental disorders.
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Affiliation(s)
- Liubov
S. Kalinichenko
- Department
of Psychiatry and Psychotherapy, University
Clinic, Friedrich-Alexander-University of Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - Johannes Kornhuber
- Department
of Psychiatry and Psychotherapy, University
Clinic, Friedrich-Alexander-University of Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - Steffen Sinning
- Department
of Forensic Medicine, Aarhus University, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
| | - Jana Haase
- School
of Biomolecular and Biomedical Science, UCD Conway Institute, University College Dublin, Dublin, Ireland
| | - Christian P. Müller
- Department
of Psychiatry and Psychotherapy, University
Clinic, Friedrich-Alexander-University of Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany
- Institute
of Psychopharmacology, Central Institute of Mental Health, Medical
Faculty Mannheim, Heidelberg University, 69047, Mannheim, Germany
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3
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De Giorgi R, Rizzo Pesci N, Rosso G, Maina G, Cowen PJ, Harmer CJ. The pharmacological bases for repurposing statins in depression: a review of mechanistic studies. Transl Psychiatry 2023; 13:253. [PMID: 37438361 PMCID: PMC10338465 DOI: 10.1038/s41398-023-02533-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Revised: 06/13/2023] [Accepted: 06/20/2023] [Indexed: 07/14/2023] Open
Abstract
Statins are commonly prescribed medications widely investigated for their potential actions on the brain and mental health. Pre-clinical and clinical evidence suggests that statins may play a role in the treatment of depressive disorders, but only the latter has been systematically assessed. Thus, the physiopathological mechanisms underlying statins' putative antidepressant or depressogenic effects have not been established. This review aims to gather available evidence from mechanistic studies to strengthen the pharmacological basis for repurposing statins in depression. We used a broad, well-validated search strategy over three major databases (Pubmed/MEDLINE, Embase, PsychINFO) to retrieve any mechanistic study investigating statins' effects on depression. The systematic search yielded 8068 records, which were narrowed down to 77 relevant papers. The selected studies (some dealing with more than one bodily system) described several neuropsychopharmacological (44 studies), endocrine-metabolic (17 studies), cardiovascular (6 studies) and immunological (15 studies) mechanisms potentially contributing to the effects of statins on mood. Numerous articles highlighted the beneficial effect of statins on depression, particularly through positive actions on serotonergic neurotransmission, neurogenesis and neuroplasticity, hypothalamic-pituitary axis regulation and modulation of inflammation. The role of other mechanisms, especially the association between statins, lipid metabolism and worsening of depressive symptoms, appears more controversial. Overall, most mechanistic evidence supports an antidepressant activity for statins, likely mediated by a variety of intertwined processes involving several bodily systems. Further research in this area can benefit from measuring relevant biomarkers to inform the selection of patients most likely to respond to statins' antidepressant effects while also improving our understanding of the physiopathological basis of depression.
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Affiliation(s)
- Riccardo De Giorgi
- University of Oxford, Department of Psychiatry, Warneford Hospital, Warneford Lane, Oxfordshire, Oxford, OX3 7JX, United Kingdom.
- Oxford Health NHS Foundation Trust, Warneford Hospital, Warneford Lane, Oxfordshire, Oxford, OX3 7JX, United Kingdom.
| | - Nicola Rizzo Pesci
- University of Turin, Department of Neurosciences "Rita Levi Montalcini", Via Cherasco 15, Turin, 10126, Italy
| | - Gianluca Rosso
- University of Turin, Department of Neurosciences "Rita Levi Montalcini", Via Cherasco 15, Turin, 10126, Italy
| | - Giuseppe Maina
- University of Turin, Department of Neurosciences "Rita Levi Montalcini", Via Cherasco 15, Turin, 10126, Italy
| | - Philip J Cowen
- University of Oxford, Department of Psychiatry, Warneford Hospital, Warneford Lane, Oxfordshire, Oxford, OX3 7JX, United Kingdom
- Oxford Health NHS Foundation Trust, Warneford Hospital, Warneford Lane, Oxfordshire, Oxford, OX3 7JX, United Kingdom
| | - Catherine J Harmer
- University of Oxford, Department of Psychiatry, Warneford Hospital, Warneford Lane, Oxfordshire, Oxford, OX3 7JX, United Kingdom
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4
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Roy A, Patra SK. Lipid Raft Facilitated Receptor Organization and Signaling: A Functional Rheostat in Embryonic Development, Stem Cell Biology and Cancer. Stem Cell Rev Rep 2023; 19:2-25. [PMID: 35997871 DOI: 10.1007/s12015-022-10448-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/14/2022] [Indexed: 01/29/2023]
Abstract
Molecular views of plasma membrane organization and dynamics are gradually changing over the past fifty years. Dynamics of plasma membrane instigate several signaling nexuses in eukaryotic cells. The striking feature of plasma membrane dynamics is that, it is internally transfigured into various subdomains of clustered macromolecules. Lipid rafts are nanoscale subdomains, enriched with cholesterol and sphingolipids, reside as floating entity mostly on the exoplasmic leaflet of the lipid bilayer. In terms of functionality, lipid rafts are unique among other membrane subdomains. Herein, advances on the roles of lipid rafts in cellular physiology and homeostasis are discussed, precisely, on how rafts dynamically harbor signaling proteins, including GPCRs, catalytic receptors, and ionotropic receptors within it and orchestrate multiple signaling pathways. In the developmental proceedings signaling are designed for patterning of overall organism and they differ from the somatic cell physiology and signaling of fully developed organisms. Some of the developmental signals are characteristic in maintenance of stemness and activated during several types of tumor development and cancer progression. The harmony between extracellular signaling and lineage specific transcriptional programs are extremely important for embryonic development. The roles of plasma membrane lipid rafts mediated signaling in lineage specificity, early embryonic development, stem cell maintenance are emerging. In view of this, we have highlighted and analyzed the roles of lipid rafts in receptor organization, cell signaling, and gene expression during embryonic development; from pre-implantation through the post-implantation phase, in stem cell and cancer biology.
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Affiliation(s)
- Ankan Roy
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, Odisha, 769008, India
| | - Samir Kumar Patra
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, Odisha, 769008, India.
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5
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De Giorgi R, Cowen PJ, Harmer CJ. Statins in depression: a repurposed medical treatment can provide novel insights in mental health. Int Rev Psychiatry 2022; 34:699-714. [PMID: 36786109 DOI: 10.1080/09540261.2022.2113369] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
Depression has a large burden, but the development of new drugs for its treatment has proved difficult. Progresses in neuroscience have highlighted several physiopathological pathways, notably inflammatory and metabolic ones, likely involved in the genesis of depressive symptoms. A novel strategy proposes to repurpose established medical treatments of known safety and to investigate their potential antidepressant activity. Among numerous candidates, growing evidence suggests that statins may have a positive role in the treatment of depressive disorders, although some have raised concerns about possible depressogenic effects of these widely prescribed medications. This narrative review summarises relevant findings from translational studies implicating many interconnected neurobiological and neuropsychological, cardiovascular, endocrine-metabolic, and immunological mechanisms by which statins could influence mood. Also, the most recent clinical investigations on the effects of statins in depression are presented. Overall, the use of statins for the treatment of depressive symptoms cannot be recommended based on the available literature, though this might change as several larger, methodologically robust studies are being conducted. Nevertheless, statins can already be acknowledged as a driver of innovation in mental health, as they provide a novel perspective to the physical health of people with depression and for the development of more precise antidepressant treatments.
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Affiliation(s)
- Riccardo De Giorgi
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, United Kingdom.,Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, United Kingdom
| | - Philip J Cowen
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, United Kingdom.,Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, United Kingdom
| | - Catherine J Harmer
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, United Kingdom.,Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, United Kingdom
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6
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Morin EE, Salbato S, Walker BR, Naik JS. Endothelial cell membrane cholesterol content regulates the contribution of TRPV4 channels in ACh-induced vasodilation in rat gracilis arteries. Microcirculation 2022; 29:e12774. [PMID: 35689491 PMCID: PMC10389065 DOI: 10.1111/micc.12774] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 05/26/2022] [Accepted: 06/06/2022] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Our previous work demonstrated that endothelial cell (EC) membrane cholesterol is reduced following 48 h of chronic hypoxia (CH). CH couples endothelial transient receptor potential subfamily V member 4 (TRPV4) channels to muscarinic receptor signaling through an endothelium-dependent hyperpolarization (EDH) pathway does not present in control animals. TRVPV4 channel activity has been shown to be regulated by membrane cholesterol. Hence, we hypothesize that acute manipulation of endothelial cell membrane cholesterol inversely determines the contribution of TRPV4 channels to endothelium-dependent vasodilation. METHODS Male Sprague-Dawley rats were exposed to ambient atmospheric (atm.) pressure or 48-h of hypoxia (0.5 atm). Vasodilation to acetylcholine (ACh) was determined using pressure myography in gracilis arteries. EC membrane cholesterol was depleted using methyl-β-cyclodextrin (MβCD) and supplemented with MβCD-cholesterol. RESULTS Inhibiting TRPV4 did not affect ACh-induced vasodilation in normoxic controls. However, TRPV4 inhibition reduced resting diameter in control arteries suggesting basal activity. TRPV4 contributes to ACh-induced vasodilation in these arteries when EC membrane cholesterol is depleted. Inhibiting TRPV4 attenuated ACh-induced vasodilation in arteries from CH animals that exhibit lower EC membrane cholesterol than normoxic controls. EC cholesterol repletion in arteries from CH animals abolished the contribution of TRPV4 to ACh-induced vasodilation. CONCLUSION Endothelial cell membrane cholesterol impedes the contribution of TRPV4 channels in EDH-mediated dilation. These results provide additional evidence for the importance of plasma membrane cholesterol content in regulating intracellular signaling and vascular function.
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Affiliation(s)
- Emily E Morin
- Department of Cell Biology and Physiology, University of New Mexico School of Medicine, Albuquerque, New Mexico, USA
| | - Sophia Salbato
- Department of Cell Biology and Physiology, University of New Mexico School of Medicine, Albuquerque, New Mexico, USA
| | - Benjimen R Walker
- Department of Cell Biology and Physiology, University of New Mexico School of Medicine, Albuquerque, New Mexico, USA
| | - Jay S Naik
- Department of Cell Biology and Physiology, University of New Mexico School of Medicine, Albuquerque, New Mexico, USA
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7
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Sphingolipid control of cognitive functions in health and disease. Prog Lipid Res 2022; 86:101162. [DOI: 10.1016/j.plipres.2022.101162] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 03/10/2022] [Accepted: 03/12/2022] [Indexed: 12/14/2022]
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8
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Irving H, Turek I, Kettle C, Yaakob N. Tapping into 5-HT 3 Receptors to Modify Metabolic and Immune Responses. Int J Mol Sci 2021; 22:ijms222111910. [PMID: 34769340 PMCID: PMC8584345 DOI: 10.3390/ijms222111910] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 10/28/2021] [Accepted: 10/29/2021] [Indexed: 02/07/2023] Open
Abstract
5-hydroxytryptamine type 3 (5-HT3) receptors are ligand gated ion channels, which clearly distinguish their mode of action from the other G-protein coupled 5-HT or serotonin receptors. 5-HT3 receptors are well established targets for emesis and gastrointestinal mobility and are used as adjunct targets in treating schizophrenia. However, the distribution of these receptors is wider than the nervous system and there is potential that these additional sites can be targeted to modulate inflammatory and/or metabolic conditions. Recent progress in structural biology and pharmacology of 5-HT3 receptors have provided profound insights into mechanisms of their action. These advances, combined with insights into clinical relevance of mutations in genes encoding 5-HT3 subunits and increasing understanding of their implications in patient's predisposition to diseases and response to the treatment, open new avenues for personalized precision medicine. In this review, we recap on the current status of 5-HT3 receptor-based therapies using a biochemical and physiological perspective. We assess the potential for targeting 5-HT3 receptors in conditions involving metabolic or inflammatory disorders based on recent findings, underscoring the challenges and limitations of this approach.
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Affiliation(s)
- Helen Irving
- Department of Pharmacy and Biomedical Sciences, La Trobe Institute for Molecular Science, La Trobe University, Bendigo, VIC 3550, Australia; (I.T.); (C.K.)
- Correspondence:
| | - Ilona Turek
- Department of Pharmacy and Biomedical Sciences, La Trobe Institute for Molecular Science, La Trobe University, Bendigo, VIC 3550, Australia; (I.T.); (C.K.)
| | - Christine Kettle
- Department of Pharmacy and Biomedical Sciences, La Trobe Institute for Molecular Science, La Trobe University, Bendigo, VIC 3550, Australia; (I.T.); (C.K.)
| | - Nor Yaakob
- Drug and Herbal Research Centre, Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur 50300, Malaysia;
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9
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He JH, Liu RP, Peng YM, Guo Q, Zhu LB, Lian YZ, Hu BL, Fan HH, Zhang X, Zhu JH. Differential and paradoxical roles of new-generation antidepressants in primary astrocytic inflammation. J Neuroinflammation 2021; 18:47. [PMID: 33602262 PMCID: PMC7890881 DOI: 10.1186/s12974-021-02097-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 02/02/2021] [Indexed: 11/18/2022] Open
Abstract
Background Selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) are commonly used new-generation drugs for depression. Depressive symptoms are thought to be closely related to neuroinflammation. In this study, we used up-to-date protocols of culture and stimulation and aimed to understand how astrocytes respond to the antidepressants. Methods Primary astrocytes were isolated and cultured using neurobasal-based serum-free medium. The cells were treated with a cytokine mixture comprising complement component 1q, tumor necrosis factor α, and interleukin 1α with or without pretreatments of antidepressants. Cell viability, phenotypes, inflammatory responses, and the underlying mechanisms were analyzed. Results All the SSRIs, including paroxetine, fluoxetine, sertraline, citalopram, and fluvoxamine, show a visible cytotoxicity within the range of applied doses, and a paradoxical effect on astrocytic inflammatory responses as manifested by the promotion of inducible nitric oxide synthase (iNOS) and/or nitric oxide (NO) and the inhibition of interleukin 6 (IL-6) and/or interleukin 1β (IL-1β). The SNRI venlafaxine was the least toxic to astrocytes and inhibited the production of IL-6 and IL-1β but with no impact on iNOS and NO. All the drugs had no regulation on the polarization of astrocytic A1 and A2 types. Mechanisms associated with the antidepressants in astrocytic inflammation route via inhibition of JNK1 activation and STAT3 basal activity. Conclusions The study demonstrated that the antidepressants possess differential cytotoxicity to astrocytes and function differently, also paradoxically for the SSRIs, to astrocytic inflammation. Our results provide novel pieces into understanding the differential efficacy and tolerability of the antidepressants in treating patients in the context of astrocytes. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-021-02097-z.
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Affiliation(s)
- Jia-Hui He
- Department of Geriatrics & Neurology, the Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, 325027, Zhejiang, China.,Department of Preventive Medicine, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China.,Department of Neurology, The Second Affiliated Hospital, Zhejiang University Medical College, Hangzhou, 310009, Zhejiang, China
| | - Rong-Pei Liu
- Department of Geriatrics & Neurology, the Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, 325027, Zhejiang, China
| | - Yi-Man Peng
- Department of Preventive Medicine, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China
| | - Qing Guo
- Department of Preventive Medicine, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China
| | - Lan-Bing Zhu
- Department of Geriatrics & Neurology, the Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, 325027, Zhejiang, China
| | - Yi-Zhi Lian
- Department of Geriatrics & Neurology, the Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, 325027, Zhejiang, China
| | - Bei-Lei Hu
- Department of Geriatrics & Neurology, the Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, 325027, Zhejiang, China
| | - Hui-Hui Fan
- Department of Geriatrics & Neurology, the Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, 325027, Zhejiang, China.,Department of Preventive Medicine, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China
| | - Xiong Zhang
- Department of Geriatrics & Neurology, the Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, 325027, Zhejiang, China.
| | - Jian-Hong Zhu
- Department of Geriatrics & Neurology, the Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, 325027, Zhejiang, China. .,Department of Preventive Medicine, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China.
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10
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Asymmetric opening of the homopentameric 5-HT 3A serotonin receptor in lipid bilayers. Nat Commun 2021; 12:1074. [PMID: 33594077 PMCID: PMC7887223 DOI: 10.1038/s41467-021-21016-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 01/06/2021] [Indexed: 12/13/2022] Open
Abstract
Pentameric ligand-gated ion channels (pLGICs) of the Cys-loop receptor family are key players in fast signal transduction throughout the nervous system. They have been shown to be modulated by the lipid environment, however the underlying mechanism is not well understood. We report three structures of the Cys-loop 5-HT3A serotonin receptor (5HT3R) reconstituted into saposin-based lipid bilayer discs: a symmetric and an asymmetric apo state, and an asymmetric agonist-bound state. In comparison to previously published 5HT3R conformations in detergent, the lipid bilayer stabilises the receptor in a more tightly packed, ‘coupled’ state, involving a cluster of highly conserved residues. In consequence, the agonist-bound receptor conformation adopts a wide-open pore capable of conducting sodium ions in unbiased molecular dynamics (MD) simulations. Taken together, we provide a structural basis for the modulation of 5HT3R by the membrane environment, and a model for asymmetric activation of the receptor. Pentameric ligand-gated ion channels (pLGICs) are key players in neurotransmission and have been shown to be modulated by the lipid environment, however the underlying mechanism is not well understood. Here, the authors report structures of the pLGIC 5-HT3A serotonin receptor reconstituted into lipid bilayer discs and reveal lipid–protein interactions as well as asymmetric activation of the homopentameric receptor.
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11
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Paz ML, Barrantes FJ. Cholesterol in myasthenia gravis. Arch Biochem Biophys 2021; 701:108788. [PMID: 33548213 DOI: 10.1016/j.abb.2021.108788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 01/13/2021] [Accepted: 01/26/2021] [Indexed: 01/03/2023]
Abstract
The cholinergic neuromuscular junction is the paradigm peripheral synapse between a motor neuron nerve ending and a skeletal muscle fiber. In vertebrates, acetylcholine is released from the presynaptic site and binds to the nicotinic acetylcholine receptor at the postsynaptic membrane. A variety of pathologies among which myasthenia gravis stands out can impact on this rapid and efficient signaling mechanism, including autoimmune diseases affecting the nicotinic receptor or other synaptic proteins. Cholesterol is an essential component of biomembranes and is particularly rich at the postsynaptic membrane, where it interacts with and modulates many properties of the nicotinic receptor. The profound changes inflicted by myasthenia gravis on the postsynaptic membrane necessarily involve cholesterol. This review analyzes some aspects of myasthenia gravis pathophysiology and associated postsynaptic membrane dysfunction, including dysregulation of cholesterol metabolism in the myocyte brought about by antibody-receptor interactions. In addition, given the extensive therapeutic use of statins as the typical cholesterol-lowering drugs, we discuss their effects on skeletal muscle and the possible implications for MG patients under chronic treatment with this type of compound.
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Affiliation(s)
- Mariela L Paz
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Cátedra de Inmunología, Buenos Aires, Argentina; CONICET, Universidad de Buenos Aires, Instituto de Estudios de la Inmunidad Humoral "Prof. Dr. Ricardo A. Margni" (IDEHU), Buenos Aires, Argentina
| | - Francisco J Barrantes
- Laboratory of Molecular Neurobiology, Biomedical Research Institute (BIOMED), UCA, CONICET, Av. Alicia Moreau de Justo 1600, C1107AFF, Buenos Aires, Argentina.
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12
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Neutral sphingomyelinase mediates the co-morbidity trias of alcohol abuse, major depression and bone defects. Mol Psychiatry 2021; 26:7403-7416. [PMID: 34584229 PMCID: PMC8872992 DOI: 10.1038/s41380-021-01304-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 09/06/2021] [Accepted: 09/09/2021] [Indexed: 02/07/2023]
Abstract
Mental disorders are highly comorbid and occur together with physical diseases, which are often considered to arise from separate pathogenic pathways. We observed in alcohol-dependent patients increased serum activity of neutral sphingomyelinase. A genetic association analysis in 456,693 volunteers found associations of haplotypes of SMPD3 coding for NSM-2 (NSM) with alcohol consumption, but also with affective state, and bone mineralisation. Functional analysis in mice showed that NSM controls alcohol consumption, affective behaviour, and their interaction by regulating hippocampal volume, cortical connectivity, and monoaminergic responses. Furthermore, NSM controlled bone-brain communication by enhancing osteocalcin signalling, which can independently supress alcohol consumption and reduce depressive behaviour. Altogether, we identified a single gene source for multiple pathways originating in the brain and bone, which interlink disorders of a mental-physical co-morbidity trias of alcohol abuse-depression/anxiety-bone disorder. Targeting NSM and osteocalcin signalling may, thus, provide a new systems approach in the treatment of a mental-physical co-morbidity trias.
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13
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Sarkar P, Mozumder S, Bej A, Mukherjee S, Sengupta J, Chattopadhyay A. Structure, dynamics and lipid interactions of serotonin receptors: excitements and challenges. Biophys Rev 2020; 13:10.1007/s12551-020-00772-8. [PMID: 33188638 PMCID: PMC7930197 DOI: 10.1007/s12551-020-00772-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 11/05/2020] [Indexed: 12/13/2022] Open
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) is an intrinsically fluorescent neurotransmitter found in organisms spanning a wide evolutionary range. Serotonin exerts its diverse actions by binding to distinct cell membrane receptors which are classified into many groups. Serotonin receptors are involved in regulating a diverse array of physiological signaling pathways and belong to the family of either G protein-coupled receptors (GPCRs) or ligand-gated ion channels. Serotonergic signaling appears to play a key role in the generation and modulation of various cognitive and behavioral functions such as sleep, mood, pain, anxiety, depression, aggression, and learning. Serotonin receptors act as drug targets for a number of diseases, particularly neuropsychiatric disorders. The signaling mechanism and efficiency of serotonin receptors depend on their amazing ability to rapidly access multiple conformational states. This conformational plasticity, necessary for the wide variety of functions displayed by serotonin receptors, is regulated by binding to various ligands. In this review, we provide a succinct overview of recent developments in generating and analyzing high-resolution structures of serotonin receptors obtained using crystallography and cryo-electron microscopy. Capturing structures of distinct conformational states is crucial for understanding the mechanism of action of these receptors, which could provide important insight for rational drug design targeting serotonin receptors. We further provide emerging information and insight from studies on interactions of membrane lipids (such as cholesterol) with serotonin receptors. We envision that a judicious combination of analysis of high-resolution structures and receptor-lipid interaction would allow a comprehensive understanding of GPCR structure, function and dynamics, thereby leading to efficient drug discovery.
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Affiliation(s)
- Parijat Sarkar
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, 500 007, India
| | - Sukanya Mozumder
- Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata, 700 032, India
- Academy of Scientific and Innovative Research, Ghaziabad, 201 002, India
| | - Aritra Bej
- Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata, 700 032, India
| | - Sujoy Mukherjee
- Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata, 700 032, India
| | - Jayati Sengupta
- Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata, 700 032, India
- Academy of Scientific and Innovative Research, Ghaziabad, 201 002, India
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14
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Thompson MJ, Baenziger JE. Structural basis for the modulation of pentameric ligand-gated ion channel function by lipids. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183304. [DOI: 10.1016/j.bbamem.2020.183304] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 03/20/2020] [Accepted: 04/05/2020] [Indexed: 10/24/2022]
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15
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Müller CP. Drug instrumentalization. Behav Brain Res 2020; 390:112672. [PMID: 32442549 DOI: 10.1016/j.bbr.2020.112672] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 04/20/2020] [Accepted: 04/21/2020] [Indexed: 12/19/2022]
Abstract
Psychoactive drugs with addiction potential are widely used by people of virtually all cultures in a non-addictive way. In order to understand this behaviour, its population penetrance, and its persistence, drug instrumentalization was suggested as a driving force for this consumption. Drug instrumentalization theory holds that psychoactive drugs are consumed in a very systematic way in order to make other, non-drug-related behaviours more efficient. Here, we review the evolutionary origin of this behaviour and its psychological mechanisms and explore the neurobiological and neuropharmacological mechanisms underlying them. Instrumentalization goals are discussed, for which an environmentally selective and mental state-dependent consumption of psychoactive drugs can be learned and maintained in a non-addictive way. A small percentage of people who regularly instrumentalize psychoactive drugs make a transition to addiction, which often starts with qualitative and quantitative changes in the instrumentalization goals. As such, addiction is proposed to develop from previously established long-term drug instrumentalization. Thus, preventing and treating drug addiction in an individualized medicine approach may essentially require understanding and supporting personal instrumentalization goals.
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Affiliation(s)
- Christian P Müller
- Department of Psychiatry and Psychotherapy, University Hospital, Friedrich-Alexander-University Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany.
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16
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Ahmed SH, Badiani A, Miczek KA, Müller CP. Non-pharmacological factors that determine drug use and addiction. Neurosci Biobehav Rev 2020; 110:3-27. [PMID: 30179633 PMCID: PMC6395570 DOI: 10.1016/j.neubiorev.2018.08.015] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 07/26/2018] [Accepted: 08/28/2018] [Indexed: 12/26/2022]
Abstract
Based on their pharmacological properties, psychoactive drugs are supposed to take control of the natural reward system to finally drive compulsory drug seeking and consumption. However, psychoactive drugs are not used in an arbitrary way as pure pharmacological reinforcement would suggest, but rather in a highly specific manner depending on non-pharmacological factors. While pharmacological effects of psychoactive drugs are well studied, neurobiological mechanisms of non-pharmacological factors are less well understood. Here we review the emerging neurobiological mechanisms beyond pharmacological reinforcement which determine drug effects and use frequency. Important progress was made on the understanding of how the character of an environment and social stress determine drug self-administration. This is expanded by new evidence on how behavioral alternatives and opportunities for drug instrumentalization generate different patterns of drug choice. Emerging evidence suggests that the neurobiology of non-pharmacological factors strongly determines pharmacological and behavioral drug action and may, thus, give rise for an expanded system's approach of psychoactive drug use and addiction.
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Affiliation(s)
- Serge H Ahmed
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, 146 rue Léo-Saignat, F-33000 Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, 146 rue Léo-Saignat, F-33000 Bordeaux, France
| | - Aldo Badiani
- Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy; Sussex Addiction Research and Intervention Centre (SARIC), School of Psychology, University of Sussex, BN1 9RH Brighton, UK
| | - Klaus A Miczek
- Psychology Department, Tufts University, Bacon Hall, 530 Boston Avenue, Medford, MA 02155, USA; Department of Neuroscience, Sackler School of Graduate Biomedical Sciences, Boston, MA 02111, USA
| | - Christian P Müller
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University Erlangen-Nuremberg, Schwabachanlage 6, 91054 Erlangen, Germany.
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17
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Abstract
Lipid microenvironments in the plasma membrane are known to influence many signal transduction pathways. Several of those pathways are critical for both the etiology and treatment of depression. Further, several signaling proteins are modified, covalently, by lipids, a process that alters their interface with the microenvironments mentioned above. This review presents a brief discussion of the interface of the above elements as well as a discussion about the participation of lipids and lipid moieties in the action of antidepressants.
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Affiliation(s)
- Nathan H Wray
- University of Illinois College of Medicine, Department of Physiology & Biophysics, Chicago, IL, United States; The Graduate Program in Neuroscience, Chicago, IL, United States
| | - Mark M Rasenick
- University of Illinois College of Medicine, Department of Physiology & Biophysics, Chicago, IL, United States; The Graduate Program in Neuroscience, Chicago, IL, United States; Department of Psychiatry, Chicago, IL, United States; The Jesse Brown VAMC, Chicago, IL, United States.
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18
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Fracassi A, Marangoni M, Rosso P, Pallottini V, Fioramonti M, Siteni S, Segatto M. Statins and the Brain: More than Lipid Lowering Agents? Curr Neuropharmacol 2019; 17:59-83. [PMID: 28676012 PMCID: PMC6341496 DOI: 10.2174/1570159x15666170703101816] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Revised: 05/24/2017] [Accepted: 06/26/2017] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Statins represent a class of medications widely prescribed to efficiently treat dyslipidemia. These drugs inhibit 3-βhydroxy 3β-methylglutaryl Coenzyme A reductase (HMGR), the rate-limiting enzyme of mevalonate (MVA) pathway. Besides cholesterol, MVA pathway leads to the production of several other compounds, which are essential in the regulation of a plethora of biological activities, including in the central nervous system. For these reasons, statins are able to induce pleiotropic actions, and acquire increased interest as potential and novel modulators in brain processes, especially during pathological conditions. OBJECTIVE The purpose of this review is to summarize and examine the current knowledge about pharmacokinetic and pharmacodynamic properties of statins in the brain. In addition, effects of statin on brain diseases are discussed providing the most up-to-date information. METHODS Relevant scientific information was identified from PubMed database using the following keywords: statins and brain, central nervous system, neurological diseases, neurodegeneration, brain tumors, mood, stroke. RESULTS 315 scientific articles were selected and analyzed for the writing of this review article. Several papers highlighted that statin treatment is effective in preventing or ameliorating the symptomatology of a number of brain pathologies. However, other studies failed to demonstrate a neuroprotective effect. CONCLUSION Even though considerable research studies suggest pivotal functional outcomes induced by statin therapy, additional investigation is required to better determine the pharmacological effectiveness of statins in the brain, and support their clinical use in the management of different neuropathologies.
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Affiliation(s)
| | | | | | | | | | | | - Marco Segatto
- Address correspondence to this author at the Department of Sense Organs, Sapienza University, viale del Policlinico 155, 00186 Rome, Italy; E-mail:
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19
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Liu JJ, Hezghia A, Shaikh SR, Cenido JF, Stark RE, Mann JJ, Sublette ME. Regulation of monoamine transporters and receptors by lipid microdomains: implications for depression. Neuropsychopharmacology 2018; 43:2165-2179. [PMID: 30022062 PMCID: PMC6135777 DOI: 10.1038/s41386-018-0133-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 05/24/2018] [Accepted: 06/18/2018] [Indexed: 12/16/2022]
Abstract
Lipid microdomains ("rafts") are dynamic, nanoscale regions of the plasma membrane enriched in cholesterol and glycosphingolipids, that possess distinctive physicochemical properties including higher order than the surrounding membrane. Lipid microdomain integrity is thought to affect neurotransmitter signaling by regulating membrane-bound protein signaling. Among the proteins potentially affected are monoaminergic receptors and transporters. As dysfunction of monoaminergic neurotransmission is implicated in major depressive disorder and other neuropsychiatric conditions, interactions with lipid microdomains may be of clinical importance. This systematic review evaluates what is known about the molecular relationships of monoamine transporter and receptor regulation to lipid microdomains. The PubMed/MeSH database was searched for original studies published in English through August 2017 concerning relationships between lipid microdomains and serotonin, dopamine and norepinephrine transporters and receptors. Fifty-seven publications were identified and assessed. Strong evidence implicates lipid microdomains in the regulation of serotonin and norepinephrine transporters; serotonin 1A, 2A, 3A, and 7A receptors; and dopamine D1 and β2 adrenergic receptors. Results were conflicting or more complex regarding lipid microdomain associations with the dopamine transporter, D2, D3, and D5 receptors; and negative with respect to β1 adrenergic receptors. Indirect evidence suggests that antidepressants, lipid-lowering drugs, and polyunsaturated fatty acids may exert effects on depression and suicide by altering the lipid milieu, thereby affecting monoaminergic transporter and receptor signaling. The lipid composition of membrane subdomains is involved in localization and trafficking of specific monoaminergic receptors and transporters. Elucidating precise mechanisms whereby lipid microdomains modulate monoamine neurotransmission in clinical contexts can have critical implications for pharmacotherapeutic targeting.
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Affiliation(s)
- Joanne J Liu
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA
- Chestnut Hill Hospital, Philadelphia, PA, USA
| | - Adrienne Hezghia
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA
- Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, NY, USA
| | - Saame Raza Shaikh
- Department of Nutrition, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Joshua F Cenido
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA
- Department of Psychiatry, Charles R. Drew University of Medicine and Science, Los Angeles, CA, USA
| | - Ruth E Stark
- Department of Chemistry and Biochemistry and CUNY Institute for Macromolecular Assemblies, The City College of New York, New York, NY, USA
- Ph.D. Program in Biochemistry, The Graduate Center of the City University of New York, New York, NY, USA
| | - J John Mann
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA
- Department of Psychiatry, Columbia University, New York, NY, USA
- Department of Radiology, Columbia University, New York, NY, USA
| | - M Elizabeth Sublette
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA.
- Department of Psychiatry, Columbia University, New York, NY, USA.
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20
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Daray FM, Mann JJ, Sublette ME. How lipids may affect risk for suicidal behavior. J Psychiatr Res 2018; 104:16-23. [PMID: 29920417 PMCID: PMC6102068 DOI: 10.1016/j.jpsychires.2018.06.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 05/30/2018] [Accepted: 06/08/2018] [Indexed: 01/06/2023]
Abstract
Suicide and nonfatal suicidal behaviors are major causes of mortality and morbidity worldwide. Variability in rates of suicide and suicidal behaviors within and between countries has been attributed to population and individual risk factors, including economic status and cultural differences, both of which can have suicide risk effects mediated through a variety of factors, of which perhaps the least understood is the role of diet. We therefore review the scientific literature concerning two major dietary lipid classes, cholesterol and polyunsaturated fatty acids (PUFAs), that have been associated with higher risk of suicide attempts and suicide. We consider potential mechanistic intermediates including serotonin transporters and receptors, toll-like receptors (TLRs), nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB), and peroxisome proliferator activated receptors (PPARs). Based on this review, we describe a theoretical model linking cholesterol and PUFA status to suicide risk, taking into account the effects of cholesterol-lowering interventions on PUFA balance, membrane lipid microdomains (rafts) as a nexus of interaction between cholesterol and omega-3 PUFAs, and downstream effects on serotonergic neurotransmission and specific inflammatory pathways.
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Affiliation(s)
- Federico M. Daray
- Institute of Pharmacology. School of Medicine. University of Buenos Aires, Paraguay 2155, piso 9, Ciudad Autónoma de Buenos Aires, Argentina, C1121ABG
| | - J. John Mann
- Department of Psychiatry, Columbia University, 1051 Riverside Drive, New York, NY 10032,Division of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, 1051 Riverside Drive, Unit 42, New York, NY 10032,Department of Radiology, Columbia University, 622 West 168th St, New York, NY 10032
| | - M. Elizabeth Sublette
- Department of Psychiatry, Columbia University, 1051 Riverside Drive, New York, NY 10032,Division of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, 1051 Riverside Drive, Unit 42, New York, NY 10032,To whom correspondence should be addressed: New York State Psychiatric Institute, 1051 Riverside Drive, Unit 42, New York, NY 10032, Tel: 646 774-7514, Fax: 646 774-7589,
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21
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Di Scala C, Fantini J, Yahi N, Barrantes FJ, Chahinian H. Anandamide Revisited: How Cholesterol and Ceramides Control Receptor-Dependent and Receptor-Independent Signal Transmission Pathways of a Lipid Neurotransmitter. Biomolecules 2018; 8:biom8020031. [PMID: 29789479 PMCID: PMC6022874 DOI: 10.3390/biom8020031] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 05/02/2018] [Accepted: 05/16/2018] [Indexed: 12/13/2022] Open
Abstract
Anandamide is a lipid neurotransmitter derived from arachidonic acid, a polyunsaturated fatty acid. The chemical differences between anandamide and arachidonic acid result in a slightly enhanced solubility in water and absence of an ionisable group for the neurotransmitter compared with the fatty acid. In this review, we first analyze the conformational flexibility of anandamide in aqueous and membrane phases. We next study the interaction of the neurotransmitter with membrane lipids and discuss the molecular basis of the unexpected selectivity of anandamide for cholesterol and ceramide from among other membrane lipids. We show that cholesterol behaves as a binding partner for anandamide, and that following an initial interaction mediated by the establishment of a hydrogen bond, anandamide is attracted towards the membrane interior, where it forms a molecular complex with cholesterol after a functional conformation adaptation to the apolar membrane milieu. The complex is then directed to the anandamide cannabinoid receptor (CB1) which displays a high affinity binding pocket for anandamide. We propose that cholesterol may regulate the entry and exit of anandamide in and out of CB1 by interacting with low affinity cholesterol recognition sites (CARC and CRAC) located in transmembrane helices. The mirror topology of cholesterol binding sites in the seventh transmembrane domain is consistent with the delivery, extraction and flip-flop of anandamide through a coordinated cholesterol-dependent mechanism. The binding of anandamide to ceramide illustrates another key function of membrane lipids which may occur independently of protein receptors. Interestingly, ceramide forms a tight complex with anandamide which blocks the degradation pathway of both lipids and could be exploited for anti-cancer therapies.
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Affiliation(s)
- Coralie Di Scala
- INMED, INSERM U1249, Parc Scientifique de Luminy, 163 Avenue de Luminy, BP13 13273 Marseille CEDEX 09, France.
| | - Jacques Fantini
- INSERM UMR_S 1072, Aix-Marseille Université, 13015 Marseille, France.
| | - Nouara Yahi
- INSERM UMR_S 1072, Aix-Marseille Université, 13015 Marseille, France.
| | - Francisco J Barrantes
- Laboratory of Molecular Neurobiology, Biomedical Research Institute (BIOMED), UCA⁻CONICET, Av. Alicia Moreau de Justo 1600, C1107AFF Buenos Aires, Argentina.
| | - Henri Chahinian
- INSERM UMR_S 1072, Aix-Marseille Université, 13015 Marseille, France.
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22
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Huston JP, Kornhuber J, Mühle C, Japtok L, Komorowski M, Mattern C, Reichel M, Gulbins E, Kleuser B, Topic B, De Souza Silva MA, Müller CP. A sphingolipid mechanism for behavioral extinction. J Neurochem 2016; 137:589-603. [PMID: 26788861 DOI: 10.1111/jnc.13537] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 01/07/2016] [Accepted: 01/08/2016] [Indexed: 12/24/2022]
Abstract
Reward-dependent instrumental behavior must continuously be re-adjusted according to environmental conditions. Failure to adapt to changes in reward contingencies may incur psychiatric disorders like anxiety and depression. When an expected reward is omitted, behavior undergoes extinction. While extinction involves active re-learning, it is also accompanied by emotional behaviors indicative of frustration, anxiety, and despair (extinction-induced depression). Here, we report evidence for a sphingolipid mechanism in the extinction of behavior. Rapid extinction, indicating efficient re-learning, coincided with a decrease in the activity of the enzyme acid sphingomyelinase (ASM), which catalyzes turnover of sphingomyelin to ceramide, in the dorsal hippocampus of rats. The stronger the decline in ASM activity, the more rapid was the extinction. Sphingolipid-focused lipidomic analysis showed that this results in a decline of local ceramide species in the dorsal hippocampus. Ceramides shape the fluidity of lipid rafts in synaptic membranes and by that way can control neural plasticity. We also found that aging modifies activity of enzymes and ceramide levels in selective brain regions. Aging also changed how the chronic treatment with corticosterone (stress) or intranasal dopamine modified regional enzyme activity and ceramide levels, coinciding with rate of extinction. These data provide first evidence for a functional ASM-ceramide pathway in the brain involved in the extinction of learned behavior. This finding extends the known cellular mechanisms underlying behavioral plasticity to a new class of membrane-located molecules, the sphingolipids, and their regulatory enzymes, and may offer new treatment targets for extinction- and learning-related psychopathological conditions. Sphingolipids are common lipids in the brain which form lipid domains at pre- and postsynaptic membrane compartments. Here we show a decline in dorsal hippocampus ceramide species together with a reduction of acid sphingomyelinase activity during extinction of conditioned behavior in rats. This reduction was associated with expression of re-learning-related behavior, but not with emotional behaviors. Read the Editorial Highlight for this article on page 485.
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Affiliation(s)
- Joseph P Huston
- Center for Behavioral Neuroscience, Institute of Experimental Psychology, Heinrich-Heine-University of Dusseldorf, Düsseldorf, Germany
| | - Johannes Kornhuber
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Christiane Mühle
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Lukasz Japtok
- Institute of Nutritional Science, Faculty of Mathematics and Natural Science, University of Potsdam, Nuthetal, Germany
| | - Mara Komorowski
- Center for Behavioral Neuroscience, Institute of Experimental Psychology, Heinrich-Heine-University of Dusseldorf, Düsseldorf, Germany
| | - Claudia Mattern
- M et P Pharma AG, Emmetten, Switzerland.,Oceanographic Center, Nova Southeastern University, Fort Lauderdale, Florida, USA
| | - Martin Reichel
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Erich Gulbins
- Department of Molecular Biology, University of Duisburg-Essen, Essen, Germany.,Department of Surgery, University of Cincinnati, Cincinnati, Ohio, USA
| | - Burkhard Kleuser
- Institute of Nutritional Science, Faculty of Mathematics and Natural Science, University of Potsdam, Nuthetal, Germany
| | - Bianca Topic
- Center for Behavioral Neuroscience, Institute of Experimental Psychology, Heinrich-Heine-University of Dusseldorf, Düsseldorf, Germany
| | - Maria A De Souza Silva
- Center for Behavioral Neuroscience, Institute of Experimental Psychology, Heinrich-Heine-University of Dusseldorf, Düsseldorf, Germany
| | - Christian P Müller
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
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23
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Brain membrane lipids in major depression and anxiety disorders. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:1052-65. [DOI: 10.1016/j.bbalip.2014.12.014] [Citation(s) in RCA: 188] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 12/06/2014] [Accepted: 12/16/2014] [Indexed: 11/13/2022]
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24
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Liu JJ, Green P, John Mann J, Rapoport SI, Sublette ME. Pathways of polyunsaturated fatty acid utilization: implications for brain function in neuropsychiatric health and disease. Brain Res 2015; 1597:220-46. [PMID: 25498862 PMCID: PMC4339314 DOI: 10.1016/j.brainres.2014.11.059] [Citation(s) in RCA: 137] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 11/11/2014] [Accepted: 11/27/2014] [Indexed: 12/28/2022]
Abstract
Essential polyunsaturated fatty acids (PUFAs) have profound effects on brain development and function. Abnormalities of PUFA status have been implicated in neuropsychiatric diseases such as major depression, bipolar disorder, schizophrenia, Alzheimer's disease, and attention deficit hyperactivity disorder. Pathophysiologic mechanisms could involve not only suboptimal PUFA intake, but also metabolic and genetic abnormalities, defective hepatic metabolism, and problems with diffusion and transport. This article provides an overview of physiologic factors regulating PUFA utilization, highlighting their relevance to neuropsychiatric disease.
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Affiliation(s)
- Joanne J Liu
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA; New York Medical College, Valhalla, NY, USA
| | - Pnina Green
- Laboratory of Metabolic Research, Felsenstein Medical Research Center, Tel Aviv University, Petach Tikva, Israel
| | - J John Mann
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA; Department of Psychiatry, Columbia University, New York, NY, USA; Department of Radiology, Columbia University, New York, NY, USA
| | - Stanley I Rapoport
- Brain Physiology and Metabolism Section, Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - M Elizabeth Sublette
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA; Department of Psychiatry, Columbia University, New York, NY, USA.
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25
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de Juan-Sanz J, Núñez E, Zafra F, Berrocal M, Corbacho I, Ibáñez I, Arribas-González E, Marcos D, López-Corcuera B, Mata AM, Aragón C. Presynaptic control of glycine transporter 2 (GlyT2) by physical and functional association with plasma membrane Ca2+-ATPase (PMCA) and Na+-Ca2+ exchanger (NCX). J Biol Chem 2014; 289:34308-24. [PMID: 25315779 DOI: 10.1074/jbc.m114.586966] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Fast inhibitory glycinergic transmission occurs in spinal cord, brainstem, and retina to modulate the processing of motor and sensory information. After synaptic vesicle fusion, glycine is recovered back to the presynaptic terminal by the neuronal glycine transporter 2 (GlyT2) to maintain quantal glycine content in synaptic vesicles. The loss of presynaptic GlyT2 drastically impairs the refilling of glycinergic synaptic vesicles and severely disrupts neurotransmission. Indeed, mutations in the gene encoding GlyT2 are the main presynaptic cause of hyperekplexia in humans. Here, we show a novel endogenous regulatory mechanism that can modulate GlyT2 activity based on a compartmentalized interaction between GlyT2, neuronal plasma membrane Ca(2+)-ATPase (PMCA) isoforms 2 and 3, and Na(+)/Ca(2+)-exchanger 1 (NCX1). This GlyT2·PMCA2,3·NCX1 complex is found in lipid raft subdomains where GlyT2 has been previously found to be fully active. We show that endogenous PMCA and NCX activities are necessary for GlyT2 activity and that this modulation depends on lipid raft integrity. Besides, we propose a model in which GlyT2·PMCA2-3·NCX complex would help Na(+)/K(+)-ATPase in controlling local Na(+) increases derived from GlyT2 activity after neurotransmitter release.
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Affiliation(s)
- Jaime de Juan-Sanz
- From the Department of Biochemistry, Weill Cornell Medical College, New York, New York 10065
| | - Enrique Núñez
- the Centro de Biología Molecular "Severo Ochoa," Universidad Autónoma de Madrid, Consejo Superior de Investigaciones Científicas, 28049-Madrid, Spain, the Centro de Investigación Biomédica en Red de Enfermedades Raras, ISCIII, 46009-Valencia, Spain, the IdiPAZ-Hospital, Universitario La Paz, 28046-Madrid, Spain, and
| | - Francisco Zafra
- the Centro de Biología Molecular "Severo Ochoa," Universidad Autónoma de Madrid, Consejo Superior de Investigaciones Científicas, 28049-Madrid, Spain, the Centro de Investigación Biomédica en Red de Enfermedades Raras, ISCIII, 46009-Valencia, Spain, the IdiPAZ-Hospital, Universitario La Paz, 28046-Madrid, Spain, and
| | - María Berrocal
- the Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura, 06006-Badajoz, Spain
| | - Isaac Corbacho
- the Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura, 06006-Badajoz, Spain
| | - Ignacio Ibáñez
- the Centro de Biología Molecular "Severo Ochoa," Universidad Autónoma de Madrid, Consejo Superior de Investigaciones Científicas, 28049-Madrid, Spain, the Centro de Investigación Biomédica en Red de Enfermedades Raras, ISCIII, 46009-Valencia, Spain, the IdiPAZ-Hospital, Universitario La Paz, 28046-Madrid, Spain, and
| | - Esther Arribas-González
- the Centro de Biología Molecular "Severo Ochoa," Universidad Autónoma de Madrid, Consejo Superior de Investigaciones Científicas, 28049-Madrid, Spain, the Centro de Investigación Biomédica en Red de Enfermedades Raras, ISCIII, 46009-Valencia, Spain, the IdiPAZ-Hospital, Universitario La Paz, 28046-Madrid, Spain, and
| | - Daniel Marcos
- the Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura, 06006-Badajoz, Spain
| | - Beatriz López-Corcuera
- the Centro de Biología Molecular "Severo Ochoa," Universidad Autónoma de Madrid, Consejo Superior de Investigaciones Científicas, 28049-Madrid, Spain, the Centro de Investigación Biomédica en Red de Enfermedades Raras, ISCIII, 46009-Valencia, Spain, the IdiPAZ-Hospital, Universitario La Paz, 28046-Madrid, Spain, and
| | - Ana M Mata
- the Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura, 06006-Badajoz, Spain
| | - Carmen Aragón
- the Centro de Biología Molecular "Severo Ochoa," Universidad Autónoma de Madrid, Consejo Superior de Investigaciones Científicas, 28049-Madrid, Spain, the Centro de Investigación Biomédica en Red de Enfermedades Raras, ISCIII, 46009-Valencia, Spain, the IdiPAZ-Hospital, Universitario La Paz, 28046-Madrid, Spain, and
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26
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The role of intracellular linkers in gating and desensitization of human pentameric ligand-gated ion channels. J Neurosci 2014; 34:7238-52. [PMID: 24849357 DOI: 10.1523/jneurosci.5105-13.2014] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
It has recently been proposed that post-translational modification of not only the M3-M4 linker but also the M1-M2 linker of pentameric ligand-gated ion channels modulates function in vivo. To estimate the involvement of the M1-M2 linker in gating and desensitization, we engineered a series of mutations to this linker of the human adult-muscle acetylcholine receptor (AChR), the α3β4 AChR and the homomeric α1 glycine receptor (GlyR). All tested M1-M2 linker mutations had little effect on the kinetics of deactivation or desensitization compared with the effects of mutations to the M2 α-helix or the extracellular M2-M3 linker. However, when the effects of mutations were assessed with 50 Hz trains of ∼1 ms pulses of saturating neurotransmitter, some mutations led to much more, and others to much less, peak-current depression than observed for the wild-type channels, suggesting that these mutations could affect the fidelity of fast synaptic transmission. Nevertheless, no mutation to this linker could mimic the irreversible loss of responsiveness reported to result from the oxidation of the M1-M2 linker cysteines of the α3 AChR subunit. We also replaced the M3-M4 linker of the α1 GlyR with much shorter peptides and found that none of these extensive changes affects channel deactivation strongly or reduces the marked variability in desensitization kinetics that characterizes the wild-type channel. However, we found that these large mutations to the M3-M4 linker can have pronounced effects on desensitization kinetics, supporting the notion that its post-translational modification could indeed modulate α1 GlyR behavior.
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27
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Neuropsychiatric adverse events associated with statins: epidemiology, pathophysiology, prevention and management. CNS Drugs 2014; 28:249-72. [PMID: 24435290 DOI: 10.1007/s40263-013-0135-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Statins, or 3-hydroxy-3-methyl-glutaryl coenzyme A reductase inhibitors, such as lovastatin, atorvastatin, simvastatin, pravastatin, fluvastatin, rosuvastatin and pitavastatin, are cholesterol-lowering drugs used in clinical practice to prevent coronary heart disease. These drugs are generally well tolerated and have been rarely associated with severe adverse effects (e.g. rhabdomyolysis). Over the years, case series and data from national registries of spontaneous adverse drug reaction reports have demonstrated the occurrence of neuropsychiatric reactions associated with statin treatment. They include behavioural alterations (severe irritability, homicidal impulses, threats to others, road rage, depression and violence, paranoia, alienation, antisocial behaviour); cognitive and memory impairments; sleep disturbance (frequent awakenings, shorter sleep duration, early morning awakenings, nightmares, sleepwalking, night terrors); and sexual dysfunction (impotence and decreased libido). Studies designed to investigate specific neuropsychiatric endpoints have yielded conflicting results. Several mechanisms, mainly related to inhibition of cholesterol biosynthesis, have been proposed to explain the detrimental effects of statins on the central nervous system. Approaches to prevent and manage such adverse effects may include drug discontinuation and introduction of dietary restrictions; maintenance of statin treatment for some weeks with close patient monitoring; switching to a different statin; dose reduction; use of ω-3 fatty acids or coenzyme Q10 supplements; and treatment with psychotropic drugs. The available information suggests that neuropsychiatric effects associated with statins are rare events that likely occur in sensitive patients. Additional data are required, and further clinical studies are needed.
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Involvement of serotonin 5-HT3 receptors in the modulation of noradrenergic transmission by serotonin reuptake inhibitors: a microdialysis study in rat brain. Psychopharmacology (Berl) 2013; 229:331-44. [PMID: 23636303 DOI: 10.1007/s00213-013-3112-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 04/08/2013] [Indexed: 10/26/2022]
Abstract
RATIONALE Selective serotonin reuptake inhibitors (SSRIs), in addition to being able to enhance serotonergic neurotransmission, are able to modulate other brain systems involved in depression. OBJECTIVES This study evaluates the neurochemical effect of the SSRI citalopram on brain noradrenergic activity and the serotonin receptor involved in this effect. METHODS Dual-probe microdialysis in the locus coeruleus (LC) and prefrontal cortex (PFC) was performed in freely awake rats. RESULTS Systemic citalopram (10 mg/kg, i.p.) increased noradrenaline (NA) in the LC (E max = 141 ± 13%) and simultaneously decreased NA in the PFC (Emax = -46 ± 7%). In the local presence into the LC of the α2-adrenoceptor antagonist RS79948 (1 μM), systemic citalopram increased NA in the LC (Emax = 157 ± 25%) and PFC (Emax = 175 ± 24%). Local citalopram (0.1-100 μM) into the LC induced NA increase in the LC (Emax = 210 ± 25%) and decrease in the PFC (Emax = -38 ± 9%). Local LC citalopram effect was abolished by LC presence of the 5-HT3 receptor antagonist MDL72222 (1 μM) but not the 5-HT1/2 receptor antagonist methiothepin (1 μM). Systemic citalopram in the LC presence of MDL72222 did not modify NA in the LC but increased NA in the PFC (Emax = 158 ± 26%). Local citalopram into the PFC enhanced NA (Emax = 376 ± 18%) in the area, which was prevented by MDL72222. CONCLUSIONS The SSRI citalopram modulates central noradrenergic neurotransmission by activation, through endogenous serotonin, of 5-HT3 receptors expressed in the somatodendritic (LC) and terminal (PFC) areas, which subsequently promote an enhancement of local NA. Therefore, 5-HT3 receptors and somatodendritic α2-adrenoceptors in the LC play an important role in the global effect of SSRIs.
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29
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Lipid raft integrity affects GABAA receptor, but not NMDA receptor modulation by psychopharmacological compounds. Int J Neuropsychopharmacol 2013; 16:1361-71. [PMID: 23217923 DOI: 10.1017/s146114571200140x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Lipid rafts have been shown to play an important role for G-protein mediated signal transduction and the function of ligand-gated ion channels including their modulation by psychopharmacological compounds. In this study, we investigated the functional significance of the membrane distribution of NMDA and GABAA receptor subunits in relation to the accumulation of the tricyclic antidepressant desipramine (DMI) and the benzodiazepine diazepam (Diaz). In the presence of Triton X-100, which allowed proper separation of the lipid raft marker proteins caveolin-1 and flotillin-1 from the transferrin receptor, all receptor subunits were shifted to the non-raft fractions. In contrast, under detergent-free conditions, NMDA and GABAA receptor subunits were detected both in raft and non-raft fractions. Diaz was enriched in non-raft fractions without Triton X-100 in contrast to DMI, which preferentially accumulated in lipid rafts. Impairment of lipid raft integrity by methyl-β-cyclodextrine (MβCD)-induced cholesterol depletion did not change the inhibitory effect of DMI at the NMDA receptor, whereas it enhanced the potentiating effect of Diaz at the GABAA receptor at non-saturating concentrations of GABA. These results support the hypothesis that the interaction of benzodiazepines with the GABAA receptor likely occurs outside of lipid rafts while the antidepressant DMI acts on ionotropic receptors both within and outside these membrane microdomains.
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30
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Zschocke J, Zimmermann N, Berning B, Ganal V, Holsboer F, Rein T. Antidepressant drugs diversely affect autophagy pathways in astrocytes and neurons--dissociation from cholesterol homeostasis. Neuropsychopharmacology 2011; 36:1754-68. [PMID: 21508931 PMCID: PMC3138654 DOI: 10.1038/npp.2011.57] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2010] [Revised: 02/17/2011] [Accepted: 03/22/2011] [Indexed: 01/25/2023]
Abstract
In the search for antidepressants' (ADs') mechanisms of action beyond their influence on monoaminergic neurotransmission, we analyzed the effects of three structurally and pharmacologically different ADs on autophagic processes in rat primary astrocytes and neurons. Autophagy has a significant role in controlling protein turnover and energy supply. Both, the tricyclic AD amitriptyline (AMI) and the selective serotonin re-uptake inhibitor citalopram (CIT) induced autophagy as mirrored by pronounced upregulation and cellular redistribution of the marker LC3B-II. Redistribution was characterized by formation of LC3B-II-positive structures indicative of autophagosomes, which associated with AVs in a time-dependent manner. Deletion of Atg5, representing a central mediator of autophagy in MEFs, led to abrogation of AMI-induced LC3B-I/II conversion. By contrast, VEN, a selective serotonin and noradrenaline reuptake inhibitor, did not promote autophagic processes in either cell type. The stimulatory impact of AMI on autophagy partly involved class-III PI3 kinase-dependent pathways as 3-methyladenine slightly diminished the effects of AMI. Autophagic flux as defined by autophagosome turnover was vastly undisturbed, and degradation of long-lived proteins was augmented upon AMI treatment. Enhanced autophagy was dissociated from drug-induced alterations in cholesterol homeostasis. Subsequent to AMI- and CIT-mediated autophagy induction, neuronal and glial viability decreased, with neurons showing signs of apoptosis. In conclusion, we report that distinct ADs promote autophagy in neural cells, with important implications on energy homeostasis.
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Affiliation(s)
- Jürgen Zschocke
- Chaperone Research Group, Max Planck Institute of Psychiatry, Munich, Germany
| | - Nicole Zimmermann
- Chaperone Research Group, Max Planck Institute of Psychiatry, Munich, Germany
| | - Barbara Berning
- Chaperone Research Group, Max Planck Institute of Psychiatry, Munich, Germany
| | - Vanessa Ganal
- Chaperone Research Group, Max Planck Institute of Psychiatry, Munich, Germany
| | - Florian Holsboer
- Chaperone Research Group, Max Planck Institute of Psychiatry, Munich, Germany
| | - Theo Rein
- Chaperone Research Group, Max Planck Institute of Psychiatry, Munich, Germany
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31
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Anacker C, Zunszain PA, Cattaneo A, Carvalho LA, Garabedian MJ, Thuret S, Price J, Pariante CM. Antidepressants increase human hippocampal neurogenesis by activating the glucocorticoid receptor. Mol Psychiatry 2011; 16:738-50. [PMID: 21483429 PMCID: PMC3121947 DOI: 10.1038/mp.2011.26] [Citation(s) in RCA: 311] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2010] [Revised: 02/08/2011] [Accepted: 02/09/2011] [Indexed: 02/06/2023]
Abstract
Antidepressants increase adult hippocampal neurogenesis in animal models, but the underlying molecular mechanisms are unknown. In this study, we used human hippocampal progenitor cells to investigate the molecular pathways involved in the antidepressant-induced modulation of neurogenesis. Because our previous studies have shown that antidepressants regulate glucocorticoid receptor (GR) function, we specifically tested whether the GR may be involved in the effects of these drugs on neurogenesis. We found that treatment (for 3-10 days) with the antidepressant, sertraline, increased neuronal differentiation via a GR-dependent mechanism. Specifically, sertraline increased both immature, doublecortin (Dcx)-positive neuroblasts (+16%) and mature, microtubulin-associated protein-2 (MAP2)-positive neurons (+26%). This effect was abolished by the GR-antagonist, RU486. Interestingly, progenitor cell proliferation, as investigated by 5'-bromodeoxyuridine (BrdU) incorporation, was only increased when cells were co-treated with sertraline and the GR-agonist, dexamethasone, (+14%) an effect which was also abolished by RU486. Furthermore, the phosphodiesterase type 4 (PDE4)-inhibitor, rolipram, enhanced the effects of sertraline, whereas the protein kinase A (PKA)-inhibitor, H89, suppressed the effects of sertraline. Indeed, sertraline increased GR transactivation, modified GR phosphorylation and increased expression of the GR-regulated cyclin-dependent kinase-2 (CDK2) inhibitors, p27(Kip1) and p57(Kip2). In conclusion, our data suggest that the antidepressant, sertraline, increases human hippocampal neurogenesis via a GR-dependent mechanism that requires PKA signaling, GR phosphorylation and activation of a specific set of genes. Our data point toward an important role for the GR in the antidepressant-induced modulation of neurogenesis in humans.
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Affiliation(s)
- C Anacker
- King's College London, Institute of Psychiatry, Section of Perinatal Psychiatry and Stress, Psychiatry and Immunology (SPI-lab), Department of Psychological Medicine, London, UK
- National Institute for Health Research ‘Biomedical Research Centre for Mental Health', Institute of Psychiatry and South London and Maudsley NHS Foundation Trust, London, UK
- King's College London, Institute of Psychiatry, Centre for the Cellular Basis of Behaviour (CCBB), London, UK
| | - P A Zunszain
- King's College London, Institute of Psychiatry, Section of Perinatal Psychiatry and Stress, Psychiatry and Immunology (SPI-lab), Department of Psychological Medicine, London, UK
| | - A Cattaneo
- King's College London, Institute of Psychiatry, Section of Perinatal Psychiatry and Stress, Psychiatry and Immunology (SPI-lab), Department of Psychological Medicine, London, UK
- Genetics Unit, IRCCS San Giovanni di Dio, Brescia, Italy
| | - L A Carvalho
- King's College London, Institute of Psychiatry, Section of Perinatal Psychiatry and Stress, Psychiatry and Immunology (SPI-lab), Department of Psychological Medicine, London, UK
| | - M J Garabedian
- Department of Microbiology, NYU School of Medicine, New York, NY, USA
| | - S Thuret
- King's College London, Institute of Psychiatry, Centre for the Cellular Basis of Behaviour (CCBB), London, UK
| | - J Price
- King's College London, Institute of Psychiatry, Centre for the Cellular Basis of Behaviour (CCBB), London, UK
| | - C M Pariante
- King's College London, Institute of Psychiatry, Section of Perinatal Psychiatry and Stress, Psychiatry and Immunology (SPI-lab), Department of Psychological Medicine, London, UK
- National Institute for Health Research ‘Biomedical Research Centre for Mental Health', Institute of Psychiatry and South London and Maudsley NHS Foundation Trust, London, UK
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32
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Abstract
Multiple plasma membrane proteins such as ion transporters and ion channels are involved in electrogenesis by setting resting membrane potentials and triggering/propagating action potentials. Recent findings strongly suggest that some of these membrane proteins are selectively transported into membrane microdomains termed lipid rafts. There appear to be multiple mechanisms for the specific protein translocation to lipid rafts, and many of these proteins exhibit distinct properties when inserted into the raft microdomains. Here the authors review the plasma membrane ion channels specifically localized at membrane lipid rafts in neurons. The mechanisms to selectively translocate these molecules to the lipid rafts and the consequences of the trafficking are also discussed.
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Affiliation(s)
- Alessandro Pristerá
- Division of Cell & Molecular Biology, Faculty of Natural Sciences, Imperial College London, London, UK
| | - Kenji Okuse
- Division of Cell & Molecular Biology, Faculty of Natural Sciences, Imperial College London, London, UK
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33
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Abstract
Serotonin (5-HT)3 receptors are the only ligand-gated ion channel of the 5-HT receptors family. They are present both in the peripheral and central nervous system and are localized in several areas involved in mood regulation (e.g., hippocampus or prefrontal cortex). Moreover, they are involved in regulation of neurotransmitter systems implicated in the pathophysiology of major depression (e.g., dopamine or GABA). Clinical and preclinical studies have suggested that 5-HT3 receptors may be a relevant target in the treatment of affective disorders. 5-HT3 receptor agonists seem to counteract the effects of antidepressants in non-clinical models, whereas 5-HT3 receptor antagonists, such as ondansetron, present antidepressant-like activities. In addition, several antidepressants, such as mirtazapine, also target 5-HT3 receptors. In this review, we will report major advances in the research of 5-HT3 receptor's roles in neuropsychiatric disorders, with special emphasis on mood and anxiety disorders.
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34
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Davies PA. Allosteric modulation of the 5-HT(3) receptor. Curr Opin Pharmacol 2011; 11:75-80. [PMID: 21342788 DOI: 10.1016/j.coph.2011.01.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Revised: 01/26/2011] [Accepted: 01/31/2011] [Indexed: 11/29/2022]
Abstract
5-Hydroxytryptamine type 3 (5-HT(3)) receptors are ligand-gated ion channels that play important roles in depression, anxiety, substance abuse, emesis, inflammatory pain, spinal nociception, gastrointestinal function, and cardiovascular reflexes. Probably the most studied modulators of 5-HT(3) receptors are the high affinity competitive 'setron' antagonists typified by ondansetron. However, there exists a broad range of compounds that modulate the 5-HT(3) receptor, not through the orthosteric site but by binding to allosteric sites. Most notable are therapeutic compounds ascribed to certain targets but that allosterically modulate 5-HT(3) receptors at clinically relevant concentrations.
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Affiliation(s)
- Paul A Davies
- Department of Neuroscience, Tufts University, 136 Harrison Ave, Boston, MA 02111, USA.
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35
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Walstab J, Rappold G, Niesler B. 5-HT(3) receptors: role in disease and target of drugs. Pharmacol Ther 2010; 128:146-69. [PMID: 20621123 DOI: 10.1016/j.pharmthera.2010.07.001] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Accepted: 06/21/2010] [Indexed: 12/19/2022]
Abstract
Serotonin type 3 (5-HT(3)) receptors are pentameric ion channels belonging to the superfamily of Cys-loop receptors. Receptor activation either leads to fast excitatory responses or modulation of neurotransmitter release depending on their neuronal localisation. 5-HT(3) receptors are known to be expressed in the central nervous system in regions involved in the vomiting reflex, processing of pain, the reward system, cognition and anxiety control. In the periphery they are present on a variety of neurons and immune cells. 5-HT(3) receptors are known to be involved in emesis, pain disorders, drug addiction, psychiatric and GI disorders. Progress in molecular genetics gives direction to personalised medical strategies for treating complex diseases such as psychiatric and functional GI disorders and unravelling individual drug responses in pharmacogenetic approaches. Here we discuss the molecular basis of 5-HT(3) receptor diversity at the DNA and protein level, of which our knowledge has greatly extended in the last decade. We also evaluate their role in health and disease and describe specific case-control studies addressing the involvement of polymorphisms of 5-HT3 subunit genes in complex disorders and responses to drugs. Furthermore, we focus on the actual state of the pharmacological knowledge concerning not only classical 5-HT(3) antagonists--the setrons--but also compounds of various substance classes targeting 5-HT(3) receptors such as anaesthetics, opioids, cannabinoids, steroids, antidepressants and antipsychotics as well as natural compounds derived from plants. This shall point to alternative treatment options modulating the 5-HT(3) receptor system and open new possibilities for drug development in the future.
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Affiliation(s)
- Jutta Walstab
- Department of Human Molecular Genetics, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
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