1
|
Hen-Shoval D, Indig-Naimer T, Moshe L, Kogan NM, Zaidan H, Gaisler-Salomon I, Okun E, Mechoulam R, Shoval G, Zalsman G, Weller A. Unraveling the molecular basis of cannabidiolic acid methyl Ester's anti-depressive effects in a rat model of treatment-resistant depression. J Psychiatr Res 2024; 175:50-59. [PMID: 38704981 DOI: 10.1016/j.jpsychires.2024.04.033] [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: 01/23/2024] [Revised: 04/03/2024] [Accepted: 04/18/2024] [Indexed: 05/07/2024]
Abstract
Major depressive disorder (MDD) stands as a significant cause of disability globally. Cannabidiolic Acid-Methyl Ester (CBDA-ME) (EPM-301, HU-580), a derivative of Cannabidiol, demonstrates immediate antidepressant-like effects, yet it has undergone only minimal evaluation in psychopharmacology. Our goal was to investigate the behavioral and potential molecular mechanisms associated with the chronic oral administration of this compound in the Wistar Kyoto (WKY) genetic model of treatment-resistant depression. Male WKY rats were subjected to behavioral assessments before and after receiving chronic (14-day) oral doses of CBDA-ME (0.5 mg/kg), 15 mg/kg of imipramine or vehicle. At the end of the study, plasma corticosterone levels and mRNA expression of various genes in the medial Prefrontal Cortex and Hippocampus were measured. Behavioral outcomes from CBDA-ME treatment indicated an antidepressant-like effect similar to imipramine, as oral ingestion reduced immobility and increased swimming duration in the Forced Swim Test. Neither treatment influenced locomotion in the Open Field Test nor preference in the Saccharin Preference Test. The behavioral impact in WKY rats coincided with reduced corticosterone serum levels, upregulated mRNA expression of Cannabinoid receptor 1, Fatty Acid Amide Hydrolase, and Corticotropin-Releasing Hormone Receptor 1, alongside downregulation of the Serotonin Transporter in the hippocampus. Additionally, there was an upregulation of CB1 mRNA expression and downregulation of Brain-Derived Neurotrophic Factor in the mPFC. These findings contribute to our limited understanding of the antidepressant effects of CBDA-ME and shed light on its potential psychopharmacological mechanisms. This discovery opens up possibilities for utilizing cannabinoids in the treatment of major depressive disorder and related conditions.
Collapse
Affiliation(s)
- D Hen-Shoval
- Psychology Department, Bar-Ilan University, Ramat Gan, Israel; Gonda Brain Research Center, Bar-Ilan University, Ramat Gan, Israel.
| | - T Indig-Naimer
- Gonda Brain Research Center, Bar-Ilan University, Ramat Gan, Israel
| | - L Moshe
- Psychology Department, Bar-Ilan University, Ramat Gan, Israel; Gonda Brain Research Center, Bar-Ilan University, Ramat Gan, Israel
| | - N M Kogan
- Institute of Personalized and Translational Medicine, Molecular Biology, Ariel University, Ariel, 4070000, Israel
| | - H Zaidan
- School of Psychological Sciences and the Integrated Brain and Behavior Research Center, University of Haifa, Haifa, Israel
| | - I Gaisler-Salomon
- School of Psychological Sciences and the Integrated Brain and Behavior Research Center, University of Haifa, Haifa, Israel
| | - E Okun
- Gonda Brain Research Center, Bar-Ilan University, Ramat Gan, Israel; The Mina and Everard Goodman Faculty of Life Sciences, Israel; The Paul Feder laboratory for Alzheimer disease research, Bar-Ilan University, Ramat Gan, Israel; Princeton Neuroscience Institute, Princeton University, Princeton, NJ, United States
| | - R Mechoulam
- Institute for Drug Research, Medical Faculty, Hebrew University, Jerusalem, Israel
| | - G Shoval
- Geha Mental Health Center, Petah Tiqva, Israel; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Princeton Neuroscience Institute, Princeton University, Princeton, NJ, United States
| | - G Zalsman
- Geha Mental Health Center, Petah Tiqva, Israel; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Division of Molecular Imaging and Neuropathology, Department of Psychiatry, Columbia University, New York, NY, United States
| | - A Weller
- Psychology Department, Bar-Ilan University, Ramat Gan, Israel; Gonda Brain Research Center, Bar-Ilan University, Ramat Gan, Israel
| |
Collapse
|
2
|
Puangsri P, Jinanarong V, Ninla-Aesong P. Impact of antidepressant treatment on complete blood count parameters and inflammatory ratios in adolescents with major depressive disorder. J Psychiatr Res 2023; 157:26-35. [PMID: 36436425 DOI: 10.1016/j.jpsychires.2022.11.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 10/23/2022] [Accepted: 11/14/2022] [Indexed: 11/18/2022]
Abstract
Neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR) are novel biomarkers of systemic inflammation in depression. This study aims to examines the impact of selective serotonin reuptake inhibitor (SSRI) treatment on complete blood count (CBC) parameters and inflammatory ratios in major depressive disorder (MDD). CBC parameters and inflammatory ratios were examined in a total of 45 drug-naive adolescents with MDD and were compared before and after SSRI treatment for 12 weeks and between responders and nonresponders. Following SSRI treatment in MDD, the red blood cell (RBC) count, hematocrit, and red cell distribution width (RDW) significantly increased. Hemoglobin tended to increase. The MCV, MCH, and MCHC values decreased significantly. White blood cell count, neutrophil percentage, monocyte count, and monocyte and basophil percentages decreased significantly. The percentage of lymphocytes significantly increased. The MLR decreased, whereas the NLR tended to decrease. Platelet count and PLR did not change significantly. A higher platelet count at baseline has been associated with non-response to SSRI treatment in patients with MDD. SSRI treatment increased RBC count, hematocrit, RDW, and lymphocyte percentage, and reduced MLR, and neutrophil and monocyte percentages in responders MDD. We suggest higher platelet counts at baseline as a potential predictor of nonresponders.
Collapse
Affiliation(s)
- Pavarud Puangsri
- Department of Clinical Science, School of Medicine, Walailak University, Nakhon Si Thammarat, Thailand.
| | - Vinn Jinanarong
- Prachuap Khiri Khan Hospital, Prachuap Khiri Khan, Thailand.
| | - Putrada Ninla-Aesong
- Department of Preclinical Science, School of Medicine, Walailak University, Nakhon Si Thammarat, Thailand.
| |
Collapse
|
3
|
The Effects of Statins on Neurotransmission and Their Neuroprotective Role in Neurological and Psychiatric Disorders. Molecules 2021; 26:molecules26102838. [PMID: 34064670 PMCID: PMC8150718 DOI: 10.3390/molecules26102838] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 05/04/2021] [Accepted: 05/10/2021] [Indexed: 11/17/2022] Open
Abstract
Statins are among the most widely used drug classes in the world. Apart from their basic mechanism of action, which is lowering cholesterol levels, many pleiotropic effects have been described so far, such as anti-inflammatory and antiatherosclerotic effects. A growing number of scientific reports have proven that these drugs have a beneficial effect on the functioning of the nervous system. The first reports proving that lipid-lowering therapy can influence the development of neurological and psychiatric diseases appeared in the 1990s. Despite numerous studies about the mechanisms by which statins may affect the functioning of the central nervous system (CNS), there are still no clear data explaining this effect. Most studies have focused on the metabolic effects of this group of drugs, however authors have also described the pleiotropic effects of statins, pointing to their probable impact on the neurotransmitter system and neuroprotective effects. The aim of this paper was to review the literature describing the impacts of statins on dopamine, serotonin, acetylcholine, and glutamate neurotransmission, as well as their neuroprotective role. This paper focuses on the mechanisms by which statins affect neurotransmission, as well as on their impacts on neurological and psychiatric diseases such as Parkinson's disease (PD), Alzheimer's disease (AD), vascular dementia (VD), stroke, and depression. The pleiotropic effects of statin usage could potentially open floodgates for research in these treatment domains, catching the attention of researchers and clinicians across the globe.
Collapse
|
4
|
Pourhamzeh M, Moravej FG, Arabi M, Shahriari E, Mehrabi S, Ward R, Ahadi R, Joghataei MT. The Roles of Serotonin in Neuropsychiatric Disorders. Cell Mol Neurobiol 2021; 42:1671-1692. [PMID: 33651238 DOI: 10.1007/s10571-021-01064-9] [Citation(s) in RCA: 79] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/12/2021] [Indexed: 12/22/2022]
Abstract
The serotonergic system extends throughout the central nervous system (CNS) and the gastrointestinal (GI) tract. In the CNS, serotonin (5-HT, 5-hydroxytryptamine) modulates a broad spectrum of functions, including mood, cognition, anxiety, learning, memory, reward processing, and sleep. These processes are mediated through 5-HT binding to 5-HT receptors (5-HTRs), are classified into seven distinct groups. Deficits in the serotonergic system can result in various pathological conditions, particularly depression, schizophrenia, mood disorders, and autism. In this review, we outlined the complexity of serotonergic modulation of physiologic and pathologic processes. Moreover, we provided experimental and clinical evidence of 5-HT's involvement in neuropsychiatric disorders and discussed the molecular mechanisms that underlie these illnesses and contribute to the new therapies.
Collapse
Affiliation(s)
- Mahsa Pourhamzeh
- Division of Neuroscience, Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Fahimeh Ghasemi Moravej
- Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mehrnoosh Arabi
- Division of Neuroscience, Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran.,Department of Radiology and Medical Physics, Faculty of Paramedicine, Kashan University of Medical Sciences, Kashan, Iran
| | - Elahe Shahriari
- Faculty of Medicine, Department of Physiology, Iran University of Medical Sciences, Tehran, Iran
| | - Soraya Mehrabi
- Division of Neuroscience, Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran.,Faculty of Medicine, Department of Physiology, Iran University of Medical Sciences, Tehran, Iran
| | - Richard Ward
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, USA
| | - Reza Ahadi
- Department of Anatomy, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.
| | - Mohammad Taghi Joghataei
- Division of Neuroscience, Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran. .,Department of Anatomy, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
5
|
Hernández-Hernández OT, Martínez-Mota L, Herrera-Pérez JJ, Jiménez-Rubio G. Role of Estradiol in the Expression of Genes Involved in Serotonin Neurotransmission: Implications for Female Depression. Curr Neuropharmacol 2019; 17:459-471. [PMID: 29956632 PMCID: PMC6520586 DOI: 10.2174/1570159x16666180628165107] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 05/23/2018] [Accepted: 06/25/2018] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND In women, changes in estrogen levels may increase the incidence and/or symptomatology of depression and affect the response to antidepressant treatments. Estrogen therapy in females may provide some mood benefits as a single treatment or might augment clinical response to antidepressants that inhibit serotonin reuptake. OBJECTIVE We analyzed the mechanisms of estradiol action involved in the regulation of gene expression that modulates serotonin neurotransmission implicated in depression. METHOD Publications were identified by a literature search on PubMed. RESULTS The participation of estradiol in depression may include regulation of the expression of tryptophan hydroxylase-2, monoamine oxidase A and B, serotonin transporter and serotonin-1A receptor. This effect is mediated by estradiol binding to intracellular estrogen receptor that interacts with estrogen response elements in the promoter sequences of tryptophan hydroxylase-2, serotonin transporter and monoamine oxidase-B. In addition to directly binding deoxyribonucleic acid, estrogen receptor can tether to other transcription factors, including activator protein 1, specificity protein 1, CCAAT/enhancer binding protein β and nuclear factor kappa B to regulate gene promoters that lack estrogen response elements, such as monoamine oxidase-A and serotonin 1A receptor. CONCLUSION Estradiol increases tryptophan hydroxylase-2 and serotonin transporter expression and decreases the expression of serotonin 1A receptor and monoamine oxidase A and B through the interaction with its intracellular receptors. The understanding of molecular mechanisms of estradiol regulation on the protein expression that modulates serotonin neurotransmission will be helpful for the development of new and more effective treatment for women with depression.
Collapse
Affiliation(s)
- Olivia Tania Hernández-Hernández
- Consejo Nacional de Ciencia y Tecnologia Research Fellow Instituto Nacional de Psiquiatria Ramon de la Fuente Muniz, Calzada Mexico-Xochimilco 101, Col. San Lorenzo Huipulco, Delegacion Tlalpan, 14370, Ciudad de Mexico, Mexico
| | - Lucía Martínez-Mota
- Laboratorio de Farmacologia Conductual, Direccion de Investigaciones en Neurociencias, Instituto Nacional de Psiquiatria Ramon de la Fuente Muniz, Calzada Mexico-Xochimilco 101, Col. San Lorenzo Huipulco, Delegacion Tlalpan, 14370, Ciudad de Mexico, Mexico
| | - José Jaime Herrera-Pérez
- Laboratorio de Farmacologia Conductual, Direccion de Investigaciones en Neurociencias, Instituto Nacional de Psiquiatria Ramon de la Fuente Muniz, Calzada Mexico-Xochimilco 101, Col. San Lorenzo Huipulco, Delegacion Tlalpan, 14370, Ciudad de Mexico, Mexico
| | - Graciela Jiménez-Rubio
- Laboratorio de Farmacologia Conductual, Direccion de Investigaciones en Neurociencias, Instituto Nacional de Psiquiatria Ramon de la Fuente Muniz, Calzada Mexico-Xochimilco 101, Col. San Lorenzo Huipulco, Delegacion Tlalpan, 14370, Ciudad de Mexico, Mexico
| |
Collapse
|
6
|
Tseng YL, Braun A, Chang JPC, Chiang ML, Tseng CY, Chen W. Micromolar concentrations of citalopram or escitalopram inhibit glycoprotein VI-mediated and integrin αIIbβ3-mediated signaling in human platelets. Toxicol Appl Pharmacol 2018; 364:106-113. [PMID: 30592962 DOI: 10.1016/j.taap.2018.12.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 12/21/2018] [Accepted: 12/24/2018] [Indexed: 01/05/2023]
Abstract
Collagen and convulxin induce platelet aggregation through glycoprotein VI (GPVI)-FcRγ-Syk signaling pathway. In addition, fibrinogen induces platelet activation through integrin αIIbβ3-FcγRIIa-Syk signaling pathway. We previously reported that high concentrations of selective serotonin reuptake inhibitors (SSRI) reduce platelet aggregation induced by collagen. We further investigated the effects of SSRI on GPVI- and αIIbβ3-mediated signaling pathway. Citalopram and escitalopram, two relatively pure SSRI, were used in this study. Both citalopram and escitalopram concentration-dependently inhibited convulxin-induced platelet aggregation, serotonin (5-HT) release and the activation of αIIbβ3. 5-HT concentration in washed platelets was unchanged after short-term treatment with citalopram. The additional 5-HT failed to fully rescue the inhibitory effect of citalopram on convulxin-induced aggregation. Convulxin-induced phosphorylation of Syk, LAT, and Akt was inhibited by citalopram and escitalopram. Citalopram inhibited the interaction between FcRγ and Syk, whereas the phosphorylation of FcRγ in response to convulxin remained unaltered. Further, citalopram inhibited the increase of the interaction between serotonin transporter and Syk induced by convulxin. In the presence of Mn2+, escitalopram inhibited the formation of lamellipodia on immobilized fibrinogen. Escitalopram did not influence the binding of fibrinogen to platelets. It inhibited the phosphorylation of Syk and PAK triggered by the adhesion on fibrinogen. Our data demonstrate that micromolar concentrations of citalopram and escitalopram inhibit GPVI- and αIIbβ3-mediated platelet functions. The mechanism of the inhibitory effect of citalopram or escitalopram is not the influence on the activation of GPVI or the interaction between fibrinogen and αIIbβ3, but the interaction between Syk and its upstream molecules.
Collapse
Affiliation(s)
- Yu-Lun Tseng
- Department of Psychiatry, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan; School of Medicine, Tzu Chi University, Hualien, Taiwan.
| | - Attila Braun
- Institute of Experimental Biomedicine, University Hospital of Würzburg, Würzburg, Germany
| | - Jane Pei-Chen Chang
- Department of Psychiatry, University Hospital and School of Medicine, China Medical University, Taichung, Taiwan
| | - Meng-Ling Chiang
- Department of Oral Pathology and Oral Diagnosis, Department of Pediatric Dentistry, Chang Gung Memorial Hospital, Taipei, Taiwan
| | - Chi-Yu Tseng
- Department of Neurology, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taichung, Taiwan; School of Medicine, Tzu Chi University, Hualien, Taiwan
| | - Wenchun Chen
- Aflac Cancer and Blood Disorders Center, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| |
Collapse
|
7
|
Decker AM, Blough BE. Development of serotonin transporter reuptake inhibition assays using JAR cells. J Pharmacol Toxicol Methods 2018; 92:52-56. [PMID: 29555537 DOI: 10.1016/j.vascn.2018.03.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 02/13/2018] [Accepted: 03/14/2018] [Indexed: 11/17/2022]
Abstract
INTRODUCTION The development and validation of serotonin transporter reuptake inhibition assays in 96-well format using commercially available human placental choriocarcinoma JAR cells is described. METHODS JAR cells were first shown to uptake [3H]serotonin in a saturable fashion with a KM value of 1 μM as determined by a Michaelis-Menten kinetic analysis. The cells were then utilized to determine the reuptake inhibition potencies of known ligands and the results were compared with results previously generated in the two most commonly used transporter assays (rat brain synaptosomes and transfected HEK293 cells). RESULTS Examination of a variety of ligands including selective serotonin reuptake inhibitors, tricyclic antidepressants, piperazine derivatives, and phenyltropane derivatives demonstrated that JAR cells are capable of detecting reuptake inhibition activity of a variety of ligands with potencies that correlate with one or both of the other assays. DISCUSSION This study demonstrates a novel pharmacological method of assessing human serotonin transporter reuptake inhibition activity using commercially available JAR cells. Our results show that JAR cells provide an easily available and good alternative to using rat brain tissue and HEK293 cells, with the advantage of studying serotonin transporter reuptake inhibition in a human background.
Collapse
Affiliation(s)
- Ann M Decker
- Center for Drug Discovery, RTI International, Research Triangle Park, NC 27709, USA.
| | - Bruce E Blough
- Center for Drug Discovery, RTI International, Research Triangle Park, NC 27709, USA.
| |
Collapse
|
8
|
Wong-Lin K, Wang DH, Moustafa AA, Cohen JY, Nakamura K. Toward a multiscale modeling framework for understanding serotonergic function. J Psychopharmacol 2017; 31:1121-1136. [PMID: 28417684 PMCID: PMC5606304 DOI: 10.1177/0269881117699612] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Despite its importance in regulating emotion and mental wellbeing, the complex structure and function of the serotonergic system present formidable challenges toward understanding its mechanisms. In this paper, we review studies investigating the interactions between serotonergic and related brain systems and their behavior at multiple scales, with a focus on biologically-based computational modeling. We first discuss serotonergic intracellular signaling and neuronal excitability, followed by neuronal circuit and systems levels. At each level of organization, we will discuss the experimental work accompanied by related computational modeling work. We then suggest that a multiscale modeling approach that integrates the various levels of neurobiological organization could potentially transform the way we understand the complex functions associated with serotonin.
Collapse
Affiliation(s)
- KongFatt Wong-Lin
- Intelligent Systems Research Centre, School of Computing and Intelligent Systems, University of Ulster, Magee Campus, Derry~Londonderry, UK
| | - Da-Hui Wang
- School of Systems Science, and National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China
| | - Ahmed A Moustafa
- School of Social Sciences and Psychology, and Marcs Institute for Brain and Behaviour, University of Western Sydney, Sydney, Australia
| | - Jeremiah Y Cohen
- Solomon H. Snyder Department of Neuroscience, Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Kae Nakamura
- Department of Physiology, Kansai Medical University, Hirakata, Osaka, Japan
| |
Collapse
|
9
|
Abstract
Products containing psychoactive synthetic cathinones, such as mephedrone and 3,4-methylenedioxypyrovalerone (MDPV) are prevalent in our society. Synthetic cathinones are structurally similar to methamphetamine, and numerous synthetics have biological activity at dopamine, serotonin, and norepinephrine transporters. Importantly, monoamine transporters co-transport sodium ions along with their substrate, and movement of substrates and ions through the transporter can generate measurable ionic currents. Here we review how electrophysiological information has enabled us to determine how synthetic cathinones affect transporter-mediated currents in cells that express these transporters. Specifically, drugs that act as transporter substrates induce inward depolarizing currents when cells are held near their resting membrane potential, whereas drugs that act as transporter blockers induce apparent outward currents by blocking an inherent inward leak current. We have employed the two-electrode voltage-clamp technique in Xenopus laevis oocytes overexpressing monoamine transporters to determine whether synthetic cathinones found in the so-called bath salts products behave as blockers or substrates. We also examined the structure-activity relationships for synthetic cathinone analogs related to the widely abused compound MDPV, a common constituent in "bath salts" possessing potent actions at the dopamine transporter.
Collapse
Affiliation(s)
- Ernesto Solis
- In Vivo Electrophysiology Unit, Behavioral Neuroscience Research Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, Triad Technology Center, 333 Cassell Drive, Suite 2200, Baltimore, MD, 21224, USA.
| |
Collapse
|
10
|
Physical and functional interactions between the serotonin transporter and the neutral amino acid transporter ASCT2. Biochem J 2016; 473:1953-65. [DOI: 10.1042/bcj20160315] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 05/03/2016] [Indexed: 01/23/2023]
Abstract
The activity of serotonergic systems depends on the reuptake of extracellular serotonin via its plasma membrane serotonin [5-HT (5-hydroxytryptamine)] transporter (SERT), a member of the Na+/Cl−-dependent solute carrier 6 family. SERT is finely regulated by multiple molecular mechanisms including its physical interaction with intracellular proteins. The majority of previously identified SERT partners that control its functional activity are soluble proteins, which bind to its intracellular domains. SERT also interacts with transmembrane proteins, but its association with other plasma membrane transporters remains to be established. Using a proteomics strategy, we show that SERT associates with ASCT2 (alanine–serine–cysteine–threonine 2), a member of the solute carrier 1 family co-expressed with SERT in serotonergic neurons and involved in the transport of small neutral amino acids across the plasma membrane. Co-expression of ASCT2 with SERT in HEK (human embryonic kidney)-293 cells affects glycosylation and cell-surface localization of SERT with a concomitant reduction in its 5-HT uptake activity. Conversely, depletion of cellular ASCT2 by RNAi enhances 5-HT uptake in both HEK-293 cells and primary cultured mesencephalon neurons. Mimicking the effect of ASCT2 down-regulation, treatment of HEK-293 cells and neurons with the ASCT2 inhibitor D-threonine also increases 5-HT uptake. Moreover, D-threonine does not enhance further the maximal velocity of 5-HT uptake in cells depleted of ASCT2. Collectively, these findings provide evidence for a complex assembly involving SERT and a member of another solute carrier family, which strongly influences the subcellular distribution of SERT and the reuptake of 5-HT.
Collapse
|
11
|
Gururajan A, Clarke G, Dinan TG, Cryan JF. Molecular biomarkers of depression. Neurosci Biobehav Rev 2016; 64:101-33. [DOI: 10.1016/j.neubiorev.2016.02.011] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 01/11/2016] [Accepted: 02/12/2016] [Indexed: 12/22/2022]
|
12
|
Schwamborn R, Brown E, Haase J. Elevation of cortical serotonin transporter activity upon peripheral immune challenge is regulated independently of p38 mitogen-activated protein kinase activation and transporter phosphorylation. J Neurochem 2016; 137:423-35. [DOI: 10.1111/jnc.13596] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 02/12/2016] [Accepted: 02/23/2016] [Indexed: 12/27/2022]
Affiliation(s)
- Robert Schwamborn
- UCD School of Biomolecular and Biomedical Science; UCD Conway Institute; University College Dublin; Dublin Ireland
| | - Eric Brown
- UCD School of Biomolecular and Biomedical Science; UCD Conway Institute; University College Dublin; Dublin Ireland
| | - Jana Haase
- UCD School of Biomolecular and Biomedical Science; UCD Conway Institute; University College Dublin; Dublin Ireland
| |
Collapse
|
13
|
Bansal R, Peterson BS, Gingrich J, Hao X, Odgerel Z, Warner V, Wickramaratne PJ, Talati A, Ansorge M, Brown AS, Sourander A, Weissman MM. Serotonin signaling modulates the effects of familial risk for depression on cortical thickness. Psychiatry Res 2016; 248:83-93. [PMID: 26774425 PMCID: PMC4905570 DOI: 10.1016/j.pscychresns.2016.01.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Revised: 11/07/2015] [Accepted: 01/03/2016] [Indexed: 01/18/2023]
Abstract
Depression is a highly familial and a heritable illness that is more prevalent in the biological offspring of the depressed individuals than in the general population. In a 3-generation, 30-year, longitudinal study of individuals at either a high(HR) or a low(LR) familial risk for depression, we previously showed cortical thinning in the right hemisphere was an endophenotype for the familial risk. In this study, we assessed whether the effects of familial risk were modulated by the serotonin-transporter-linked polymorphic region (5-HTTLPR). We measured cortical thickness using MRI of the brain and associated it with 5-HTTLPR polymorphism in 76 HR and 53 LR individuals. We studied the effects of genotype and gene-by-risk interaction on cortical thickness while controlling for the confounding effects of age and gender, and for the familial relatedness by applying a variance component model with random effects for genotype. The results showed significant effects of gene-by-risk interaction on thickness: The "s" allele was associated with thinner cortex in the LR individuals whereas with thicker cortex in the HR individuals. The opposing gene effects across the two risk groups were likely due to either epistatic effects and/or differing modulation of the neural plasticity by the altered 5-HT signaling in utero.
Collapse
Affiliation(s)
- Ravi Bansal
- Department of Pediatrics, Keck School of Medicine, Los Angeles, CA 90033, United States; Institute for the Developing Mind, The Saban Research Institute, CHLA, CA 90027, United States.
| | - Bradley S Peterson
- Department of Pediatrics, Keck School of Medicine, Los Angeles, CA 90033, United States; Institute for the Developing Mind, The Saban Research Institute, CHLA, CA 90027, United States
| | - Jay Gingrich
- Department of Psychiatry, Columbia University, New York, NY 10032, United States; New York State Psychiatric Institute, New York, NY 10032, United States
| | - Xuejun Hao
- Department of Psychiatry, Columbia University, New York, NY 10032, United States; New York State Psychiatric Institute, New York, NY 10032, United States
| | - Zagaa Odgerel
- Department of Psychiatry, Columbia University, New York, NY 10032, United States; New York State Psychiatric Institute, New York, NY 10032, United States
| | - Virginia Warner
- Department of Psychiatry, Columbia University, New York, NY 10032, United States; New York State Psychiatric Institute, New York, NY 10032, United States
| | - Priya J Wickramaratne
- Department of Psychiatry, Columbia University, New York, NY 10032, United States; New York State Psychiatric Institute, New York, NY 10032, United States
| | - Ardesheer Talati
- Department of Psychiatry, Columbia University, New York, NY 10032, United States; New York State Psychiatric Institute, New York, NY 10032, United States
| | - Mark Ansorge
- Department of Psychiatry, Columbia University, New York, NY 10032, United States; New York State Psychiatric Institute, New York, NY 10032, United States
| | - Alan S Brown
- Department of Psychiatry, Columbia University, New York, NY 10032, United States; New York State Psychiatric Institute, New York, NY 10032, United States
| | - Andre Sourander
- Department of Psychiatry, Columbia University, New York, NY 10032, United States; Department of Child Psychiatry, University of Turku, Turku, Finland
| | - Myrna M Weissman
- Department of Psychiatry, Columbia University, New York, NY 10032, United States; New York State Psychiatric Institute, New York, NY 10032, United States
| |
Collapse
|
14
|
Jawahar MC, Murgatroyd C, Harrison EL, Baune BT. Epigenetic alterations following early postnatal stress: a review on novel aetiological mechanisms of common psychiatric disorders. Clin Epigenetics 2015; 7:122. [PMID: 26583053 PMCID: PMC4650349 DOI: 10.1186/s13148-015-0156-3] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 11/08/2015] [Indexed: 11/10/2022] Open
Abstract
Stressor exposure during early life has the potential to increase an individual’s susceptibility to a number of neuropsychiatric conditions such as mood and anxiety disorders and schizophrenia in adulthood. This occurs in part due to the dysfunctional stress axis that persists following early adversity impairing stress responsivity across life. The mechanisms underlying the prolonged nature of this vulnerability remain to be established. Alterations in the epigenetic signature of genes involved in stress responsivity may represent one of the neurobiological mechanisms. The overall aim of this review is to provide current evidence demonstrating changes in the epigenetic signature of candidate gene(s) in response to early environmental adversity. More specifically, this review analyses the epigenetic signatures of postnatal adversity such as childhood abuse or maltreatment and later-life psychopathology in human and animal models of early life stress. The results of this review shows that focus to date has been on genes involved in the regulation of hypothalamic-pituitary-adrenal (HPA) axis and its correlation to subsequent neurobiology, for example, the role of glucocorticoid receptor gene. However, epigenetic changes in other candidate genes such as brain-derived neurotrophic factor (BDNF) and serotonin transporter are also implicated in early life stress (ELS) and susceptibility to adult psychiatric disorders. DNA methylation is the predominantly studied epigenetic mark followed by histone modifications specifically acetylation and methylation. Further, these epigenetic changes are cell/tissue-specific in regulating expression of genes, providing potential biomarkers for understanding the trajectory of early stress-induced susceptibility to adult psychiatric disorders.
Collapse
Affiliation(s)
- Magdalene C Jawahar
- Discipline of Psychiatry, School of Medicine, University of Adelaide, Adelaide, SA 5005 Australia
| | - Chris Murgatroyd
- School of HealthCare Science, Manchester Metropolitan University, Manchester, UK
| | - Emma L Harrison
- Discipline of Psychiatry, School of Medicine, University of Adelaide, Adelaide, SA 5005 Australia ; School of Medicine and Dentistry, James Cook University, Townsville City, Australia
| | - Bernhard T Baune
- Discipline of Psychiatry, School of Medicine, University of Adelaide, Adelaide, SA 5005 Australia
| |
Collapse
|
15
|
Krawczyk N, Meyer A, Fonseca M, Lima J. Suicide mortality among agricultural workers in a region with intensive tobacco farming and use of pesticides in Brazil. J Occup Environ Med 2014; 56:993-1000. [PMID: 25046321 PMCID: PMC5240450 DOI: 10.1097/jom.0000000000000214] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
OBJECTIVE To investigate whether suicide risk among agricultural workers is higher in regions with heavier pesticide use and/or presence of tobacco farming. METHODS Suicide mortality data were gathered from residents of the Brazilian state of Alagoas. Agricultural census data were used to arrange and classify Alagoas cities into distribution groups on the basis of variables concerning pesticide use and/or tobacco farming. Mortality odds ratio calculations were then used to compare suicide risk among agricultural and nonagricultural workers in different groups. RESULTS Suicide risk was higher among agricultural workers than among nonagricultural workers, elevated in regions that used more pesticides, and greatest in regions that produced more tobacco. CONCLUSIONS This is one of the first studies of its kind to suggest that combined effects of pesticide and tobacco exposure may be linked to higher suicide risk among agricultural workers.
Collapse
Affiliation(s)
- Noa Krawczyk
- From the Department of Preventative Medicine (Ms Krawczyk and Ms Fonseca), Icahn School of Medicine at Mount Sinai, New York, NY; Institute for Studies in Collective Health (Dr Meyer), Universidade Federal do Rio de Janeiro; and Department of Biochemistry (Dr Lima), Universidade Federal do Estado do Rio de Janeiro, RJ, Brazil
| | | | | | | |
Collapse
|
16
|
Calcineurin interacts with the serotonin transporter C-terminus to modulate its plasma membrane expression and serotonin uptake. J Neurosci 2013; 33:16189-99. [PMID: 24107951 DOI: 10.1523/jneurosci.0076-13.2013] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Homeostasis of serotonergic transmission critically depends on the rate of serotonin reuptake via its plasma membrane transporter (SERT). SERT activity is tightly regulated by multiple mechanisms, including physical association with intracellular proteins and post-translational modifications, such as phosphorylation, but these mechanisms remain partially understood. Here, we show that SERT C-terminal domain recruits both the catalytic and regulatory subunits of the Ca(2+)-activated protein phosphatase calcineurin (CaN) and that the physical association of SERT with CaN is promoted by CaN activity. Coexpression of constitutively active CaN with SERT increases SERT cell surface expression and 5-HT uptake in HEK-293 cells. It also prevents the reduction of 5-HT uptake induced by an acute treatment of cells with the protein kinase C activator β-PMA and concomitantly decreases PMA-elicited SERT phosphorylation. In addition, constitutive activation of CaN in vivo favors 5-HT uptake in the adult mouse brain, whereas CaN inhibition reduces cerebral 5-HT uptake. Constitutive activation of CaN also decreases immobility in the forced swim test, indicative of an antidepressant-like effect of CaN. These results identify CaN as an important regulator of SERT activity in the adult brain and provide a novel molecular substrate of clinical interest for the understanding of increased risk of mood disorders in transplanted patients treated with immunosuppressive CaN inhibitors.
Collapse
|
17
|
Shenoy AR, Dehmel T, Stettner M, Kremer D, Kieseier BC, Hartung HP, Hofstetter HH. Citalopram suppresses thymocyte cytokine production. J Neuroimmunol 2013; 262:46-52. [DOI: 10.1016/j.jneuroim.2013.06.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2012] [Revised: 05/13/2013] [Accepted: 06/17/2013] [Indexed: 12/27/2022]
|
18
|
Harrington RA, Lee LC, Crum RM, Zimmerman AW, Hertz-Picciotto I. Serotonin Hypothesis of Autism: Implications for Selective Serotonin Reuptake Inhibitor Use during Pregnancy. Autism Res 2013; 6:149-68. [DOI: 10.1002/aur.1288] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Accepted: 02/15/2013] [Indexed: 11/11/2022]
Affiliation(s)
- Rebecca A. Harrington
- Department of Epidemiology; Johns Hopkins Bloomberg School of Public Health; Baltimore; Maryland
| | - Li-Ching Lee
- Department of Epidemiology; Johns Hopkins Bloomberg School of Public Health; Baltimore; Maryland
| | - Rosa M. Crum
- Departments of Epidemiology, Psychiatry, and Mental Health; Johns Hopkins Medical Institutions; Baltimore; Maryland
| | - Andrew W. Zimmerman
- Lurie Center for Autism; Massachusetts General Hospital for Children; Lexington; Massachusetts
| | - Irva Hertz-Picciotto
- Department of Public Health Sciences and the M.I.N.D. Institute; MS1C; University of California, Davis; Davis; California
| |
Collapse
|
19
|
Liu KS, Chen SJ, Chen YW, Sung K, Wang JJ. A dose–response study on the efficacy of tricyclic antidepressants on reducing morphine-withdrawal symptoms. ACTA ACUST UNITED AC 2013; 51:18-21. [DOI: 10.1016/j.aat.2013.03.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 11/28/2012] [Accepted: 12/03/2012] [Indexed: 11/17/2022]
|
20
|
Hagan CE, McDevitt RA, Liu Y, Furay AR, Neumaier JF. 5-HT(1B) autoreceptor regulation of serotonin transporter activity in synaptosomes. Synapse 2012; 66:1024-34. [PMID: 22961814 DOI: 10.1002/syn.21608] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Accepted: 08/30/2012] [Indexed: 02/06/2023]
Abstract
Serotonin-1B (5-HT(1B) ) autoreceptors are located in serotonin (5-HT) terminals, along with serotonin transporters (SERT), and play a critical role in autoregulation of serotonergic neurotransmission and are implicated in disorders of serotonergic function, particularly emotional regulation. SERT modulates serotonergic neurotransmission by high-affinity reuptake of 5-HT. Alterations in SERT activity are associated with increased risk for depression and anxiety. Several neurotransmitter receptors are known to regulate SERT K(m) and V(max) , and previous work suggests that 5-HT(1B) autoreceptors may regulate 5-HT reuptake, in addition to modulating 5-HT release and synthesis. We used rotating disk electrode voltammetry to investigate 5-HT(1B) autoreceptor regulation of SERT-mediated 5-HT uptake into synaptosomes. The selective 5-HT(1B) antagonist SB224289 decreased SERT activity in synaptosomes prepared from wild-type but not 5-HT(1B) knockout mice, whereas SERT uptake was enhanced after pretreatment with the selective 5-HT(1B) agonist CP94253. Furthermore, SERT activity varies as a function of 5-HT(1B) receptor expression-specifically, genetic deletion of 5-HT(1B) decreased SERT function, while viral-mediated overexpression of 5-HT(1B) autoreceptors in rat raphe neurons increased SERT activity in rat hippocampal synaptosomes. Considered collectively, these results provide evidence that 5-HT(1B) autoreceptors regulate SERT activity. Because SERT clearance rate varies as a function of 5-HT(1B) autoreceptor expression levels and is modulated by both activation and inhibition of 5-HT(1B) autoreceptors, this dynamic interaction may be an important mechanism of serotonin autoregulation with therapeutic implications.
Collapse
Affiliation(s)
- Catherine E Hagan
- Department of Comparative Medicine and Graduate Program in Molecular and Cellular Biology, University of Washington, Seattle, Washington 98195, USA.
| | | | | | | | | |
Collapse
|
21
|
Wang H, Gouaux E. Substrate binds in the S1 site of the F253A mutant of LeuT, a neurotransmitter sodium symporter homologue. EMBO Rep 2012; 13:861-6. [PMID: 22836580 DOI: 10.1038/embor.2012.110] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2012] [Revised: 07/03/2012] [Accepted: 07/11/2012] [Indexed: 01/29/2023] Open
Abstract
LeuT serves as the model protein for understanding the relationships between structure, mechanism and pharmacology in neurotransmitter sodium symporters (NSSs). At the present time, however, there is a vigorous debate over whether there is a single high-affinity substrate site (S1) located at the original, crystallographically determined substrate site or whether there are two high-affinity substrates sites, one at the primary or S1 site and the other at a second site (S2) located at the base of the extracellular vestibule. In an effort to address the controversy over the number of high-affinity substrate sites in LeuT, one group studied the F253A mutant of LeuT and asserted that in this mutant substrate binds exclusively to the S2 site and that 1 mM clomipramine entirely ablates substrate binding to the S2 site. Here we study the binding of substrate to the F253A mutant of LeuT using ligand binding and X-ray crystallographic methods. Both experimental methods unambiguously show that substrate binds to the S1 site of the F253A mutant and that binding is retained in the presence of 1 mM clomipramine. These studies, in combination with previous work, are consistent with a mechanism for LeuT that involves a single high-affinity substrate binding site.
Collapse
Affiliation(s)
- Hui Wang
- Vollum Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, USA
| | | |
Collapse
|
22
|
Solis E, Zdravkovic I, Tomlinson ID, Noskov SY, Rosenthal SJ, De Felice LJ. 4-(4-(dimethylamino)phenyl)-1-methylpyridinium (APP+) is a fluorescent substrate for the human serotonin transporter. J Biol Chem 2012; 287:8852-63. [PMID: 22291010 DOI: 10.1074/jbc.m111.267757] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Monoamine transporters terminate synaptic neurotransmission and are molecular targets for antidepressants and psychostimulants. Fluorescent reporters can monitor real-time transport and are amenable for high-throughput screening. However, until now, their use has mostly been successful to study the catecholamine transporters but not the serotonin (5HT) transporter. Here, we use fluorescence microscopy, electrophysiology, pharmacology, and molecular modeling to compare fluorescent analogs of 1-methyl-4-phenylpyridinium (MPP(+)) as reporters for the human serotonin transporter (hSERT) in single cells. The fluorescent substrate 4-(4-(dimethylamino)phenyl)-1-methylpyridinium (APP(+)) exhibits superior fluorescence uptake in hSERT-expressing HEK293 cells than other MPP(+) analogs tested. APP(+) uptake is Na(+)- and Cl(-)-dependent, displaced by 5HT, and inhibited by fluoxetine, suggesting APP(+) specifically monitors hSERT activity. ASP(+), which was previously used to study catecholamine transporters, is 10 times less potent than APP(+) at inhibiting 5HT uptake and has minimal hSERT-mediated uptake. Furthermore, in hSERT-expressing oocytes voltage-clamped to -60 mV, APP(+) induced fluoxetine-sensitive hSERT-mediated inward currents, indicating APP(+) is a substrate, whereas ASP(+) induced hSERT-mediated outward currents and counteracted 5HT-induced hSERT currents, indicating ASP(+) possesses activity as an inhibitor. Extra-precise ligand receptor docking of APP(+) and ASP(+) in an hSERT homology model showed both ASP(+) and APP(+) docked favorably within the active region; accordingly, comparable concentrations are required to elicit their opposite electrophysiological responses. We conclude APP(+) is better suited than ASP(+) to study hSERT transport fluorometrically.
Collapse
Affiliation(s)
- Ernesto Solis
- Graduate Training Program in Neuroscience, Vanderbilt University School of Medicine, Nashville, Tennessee 23235, USA.
| | | | | | | | | | | |
Collapse
|
23
|
Structures of LeuT in bicelles define conformation and substrate binding in a membrane-like context. Nat Struct Mol Biol 2012; 19:212-9. [PMID: 22245965 DOI: 10.1038/nsmb.2215] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Accepted: 11/24/2011] [Indexed: 11/08/2022]
Abstract
Neurotransmitter sodium symporters (NSSs) catalyze the uptake of neurotransmitters into cells, terminating neurotransmission at chemical synapses. Consistent with the role of NSSs in the central nervous system, they are implicated in multiple diseases and disorders. LeuT, from Aquifex aeolicus, is a prokaryotic ortholog of the NSS family and has contributed to our understanding of the structure, mechanism and pharmacology of NSSs. At present, however, the functional state of LeuT in crystals grown in the presence of n-octyl-β-D-glucopyranoside (β-OG) and the number of substrate binding sites are controversial issues. Here we present crystal structures of LeuT grown in DMPC-CHAPSO bicelles and demonstrate that the conformations of LeuT-substrate complexes in lipid bicelles and in β-OG detergent micelles are nearly identical. Furthermore, using crystals grown in bicelles and the substrate leucine or the substrate analog selenomethionine, we find only a single substrate molecule in the primary binding site.
Collapse
|
24
|
Kenna GA, Roder-Hanna N, Leggio L, Zywiak WH, Clifford J, Edwards S, Kenna JA, Shoaff J, Swift RM. Association of the 5-HTT gene-linked promoter region (5-HTTLPR) polymorphism with psychiatric disorders: review of psychopathology and pharmacotherapy. PHARMACOGENOMICS & PERSONALIZED MEDICINE 2012; 5:19-35. [PMID: 23226060 PMCID: PMC3513226 DOI: 10.2147/pgpm.s23462] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Indexed: 12/15/2022]
Abstract
Serotonin (5-HT) regulates important biological and psychological processes including mood, and may be associated with the development of several psychiatric disorders. An association between psychopathology and genes that regulate 5-HT neurotransmission is a robust area of research. Identification of the genes responsible for the predisposition, development, and pharmacological response of various psychiatric disorders is crucial to the advancement of our understanding of their underlying neurobiology. This review highlights research investigating 5-HT transporter (5-HTTLPR) polymorphism, because studies investigating the impact of the 5-HTTLPR polymorphism have demonstrated significant associations with many psychiatric disorders. Decreased transcriptional activity of the S allele ("risk allele") may be associated with a heightened amygdala response leading to anxiety-related personality traits, major depressive disorder, suicide attempts, and bipolar disorder. By contrast, increased transcriptional activity of the L allele is considered protective for depression but is also associated with completed suicide, nicotine dependence, and attention deficit hyperactivity disorder. For some disorders, such as post-traumatic stress disorder and major depressive disorder, the research suggests that treatment response may vary by allele (such as an enhanced response to serotonin specific reuptake inhibitors in patients with major depressive disorder and post-traumatic stress disorder with L alleles), and for alcohol dependence, the association and treatment for S or L alleles may vary with alcoholic subtype. While some studies suggest that 5-HTTLPR polymorphism can moderate the response to pharmacotherapy, the association between 5-HTTLPR alleles and therapeutic outcomes is inconsistent. The discovery of triallelic 5-HTTLPR alleles (L(A)/L(G)/S) may help to explain some of the conflicting results of many past association studies, while concurrently providing more meaningful data in the future. Studies assessing 5-HTTLPR as the solitary genetic factor contributing to the etiology of psychiatric disorders continue to face the challenges of statistically small effect sizes and limited replication.
Collapse
Affiliation(s)
- George A Kenna
- Center for Alcohol and Addiction Studies, Department of Psychiatry and Human Behavior, Brown University, Providence
| | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Kittel-Schneider S, Kenis G, Schek J, van den Hove D, Prickaerts J, Lesch KP, Steinbusch H, Reif A. Expression of monoamine transporters, nitric oxide synthase 3, and neurotrophin genes in antidepressant-stimulated astrocytes. Front Psychiatry 2012; 3:33. [PMID: 22529824 PMCID: PMC3330247 DOI: 10.3389/fpsyt.2012.00033] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Accepted: 03/26/2012] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND There is increasing evidence that glial cells play a role in the pathomechanisms of mood disorders and the mode of action of antidepressant drugs. METHODS To examine whether there is a direct effect on the expression of different genes encoding proteins that have been implicated in the pathophysiology of affective disorders, primary astrocyte cell cultures from rats were treated with two different antidepressant drugs, imipramine and escitalopram, and the RNA expression of brain-derived neurotrophic factor (Bdnf), serotonin transporter (5Htt), dopamine transporter (Dat), and endothelial nitric oxide synthase (Nos3) was examined. RESULTS Stimulation of astroglial cell culture with imipramine, a tricyclic antidepressant, led to a significant increase of the Bdnf RNA level whereas treatment with escitalopram did not. In contrast, 5Htt was not differentially expressed after antidepressant treatment. Finally, neither Dat nor Nos3 RNA expression was detected in cultured astrocytes. CONCLUSION These data provide further evidence for a role of astroglial cells in the molecular mechanisms of action of antidepressants.
Collapse
Affiliation(s)
- Sarah Kittel-Schneider
- Department of Psychiatry, Psychosomatics and Psychotherapy, Psychiatric Neurobiology and Bipolar Disorder Program, University of Würzburg Würzburg, Germany
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Müller HK, Wegener G, Elfving B. Chronic restraint stress affects serotonin transporter uptake kinetics but not binding sites in the rat hippocampus. Synapse 2011; 66:270-2. [PMID: 21954049 DOI: 10.1002/syn.20986] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2011] [Accepted: 09/09/2011] [Indexed: 11/07/2022]
Affiliation(s)
- Heidi Kaastrup Müller
- Centre for Psychiatric Research, Laboratory for Psychiatric Neuromodulation, Aarhus University Hospital, Risskov, Denmark.
| | | | | |
Collapse
|
27
|
Best J, Nijhout HF, Reed M. Serotonin synthesis, release and reuptake in terminals: a mathematical model. Theor Biol Med Model 2010; 7:34. [PMID: 20723248 PMCID: PMC2942809 DOI: 10.1186/1742-4682-7-34] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Accepted: 08/19/2010] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Serotonin is a neurotransmitter that has been linked to a wide variety of behaviors including feeding and body-weight regulation, social hierarchies, aggression and suicidality, obsessive compulsive disorder, alcoholism, anxiety, and affective disorders. Full understanding of serotonergic systems in the central nervous system involves genomics, neurochemistry, electrophysiology, and behavior. Though associations have been found between functions at these different levels, in most cases the causal mechanisms are unknown. The scientific issues are daunting but important for human health because of the use of selective serotonin reuptake inhibitors and other pharmacological agents to treat disorders in the serotonergic signaling system. METHODS We construct a mathematical model of serotonin synthesis, release, and reuptake in a single serotonergic neuron terminal. The model includes the effects of autoreceptors, the transport of tryptophan into the terminal, and the metabolism of serotonin, as well as the dependence of release on the firing rate. The model is based on real physiology determined experimentally and is compared to experimental data. RESULTS We compare the variations in serotonin and dopamine synthesis due to meals and find that dopamine synthesis is insensitive to the availability of tyrosine but serotonin synthesis is sensitive to the availability of tryptophan. We conduct in silico experiments on the clearance of extracellular serotonin, normally and in the presence of fluoxetine, and compare to experimental data. We study the effects of various polymorphisms in the genes for the serotonin transporter and for tryptophan hydroxylase on synthesis, release, and reuptake. We find that, because of the homeostatic feedback mechanisms of the autoreceptors, the polymorphisms have smaller effects than one expects. We compute the expected steady concentrations of serotonin transporter knockout mice and compare to experimental data. Finally, we study how the properties of the the serotonin transporter and the autoreceptors give rise to the time courses of extracellular serotonin in various projection regions after a dose of fluoxetine. CONCLUSIONS Serotonergic systems must respond robustly to important biological signals, while at the same time maintaining homeostasis in the face of normal biological fluctuations in inputs, expression levels, and firing rates. This is accomplished through the cooperative effect of many different homeostatic mechanisms including special properties of the serotonin transporters and the serotonin autoreceptors. Many difficult questions remain in order to fully understand how serotonin biochemistry affects serotonin electrophysiology and vice versa, and how both are changed in the presence of selective serotonin reuptake inhibitors. Mathematical models are useful tools for investigating some of these questions.
Collapse
Affiliation(s)
- Janet Best
- Department of Mathematics, The Ohio State University, Columbus, OH 43210 USA
| | | | - Michael Reed
- Department of Mathematics, Duke University, Durham, NC 27708 USA
| |
Collapse
|
28
|
Iordanidou M, Tavridou A, Petridis I, Kyroglou S, Kaklamanis L, Christakidis D, Manolopoulos VG. Association of polymorphisms of the serotonergic system with smoking initiation in Caucasians. Drug Alcohol Depend 2010; 108:70-6. [PMID: 20060656 DOI: 10.1016/j.drugalcdep.2009.11.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Revised: 10/31/2009] [Accepted: 11/17/2009] [Indexed: 11/28/2022]
Abstract
BACKGROUND The serotonergic system may be implicated in susceptibility to nicotine dependence as nicotine increases 5-hydroxytryptamine (5-HT) release in brain and symptoms of nicotine withdrawal may be modulated by diminished serotonergic neurotransmission. We examined the association of polymorphisms of genes involved in release and receptor function of 5-HT with cigarette smoking initiation in subjects of Caucasian origin. METHODS 5-HTTLPR polymorphism of the 5-HT transporter gene and -759C/T (rs3813929) and -697G/C (rs518147) polymorphisms of the 5-HT(2C) receptor gene were analyzed in 172 smoking initiators and 254 non-initiators, using PCR-RFLP method. Smoking behavior was assessed with a questionnaire about tobacco use. RESULTS We found no differences in the frequency of the 5-HTTLPR genotypes between smoking initiators and non-initiators. However, the frequency of 5-HT(2C) -759T allele was significantly higher in non-initiators than smoking initiators (29.5% vs 16.3%, p=0.002) and the same was true for 5-HT(2C) -697C allele carriers (48.8% vs 34.9%, p=0.004). Sex-dependent analysis revealed that these increased frequencies of -759T and -697C allele carriers were present only in males. No association was observed between any quantitative measures of smoking and these three polymorphisms. CONCLUSIONS 5-HTTLPR polymorphism was not associated with smoking initiation in either male or female subjects. However, significant association was found between 5-HT(2C) receptor gene polymorphisms and smoking initiation in male Caucasian subjects.
Collapse
Affiliation(s)
- Maria Iordanidou
- Laboratory of Pharmacology, Medical School, Democritus University of Thrace, Dragana Campus, Alexandroupolis 68100, Greece
| | | | | | | | | | | | | |
Collapse
|
29
|
Kawaura K, Ogata Y, Inoue M, Honda S, Soeda F, Shirasaki T, Takahama K. The centrally acting non-narcotic antitussive tipepidine produces antidepressant-like effect in the forced swimming test in rats. Behav Brain Res 2009; 205:315-8. [DOI: 10.1016/j.bbr.2009.07.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Revised: 07/01/2009] [Accepted: 07/06/2009] [Indexed: 11/26/2022]
|
30
|
Cooke J, Grover L, Spangler P. Venlafaxine treatment stimulates expression of brain-derived neurotrophic factor protein in frontal cortex and inhibits long-term potentiation in hippocampus. Neuroscience 2009; 162:1411-9. [DOI: 10.1016/j.neuroscience.2009.05.037] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2009] [Revised: 05/12/2009] [Accepted: 05/18/2009] [Indexed: 12/27/2022]
|
31
|
Two allelic isoforms of the serotonin transporter from Schistosoma mansoni display electrogenic transport and high selectivity for serotonin. Eur J Pharmacol 2009; 616:48-57. [PMID: 19549517 DOI: 10.1016/j.ejphar.2009.06.023] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Revised: 06/04/2009] [Accepted: 06/11/2009] [Indexed: 11/22/2022]
Abstract
The human blood fluke Schistosoma mansoni is the primary cause of schistosomiasis, a debilitating disease that affects 200 million individuals in over 70 countries. The biogenic amine serotonin is essential for the survival of the parasite and serotonergic proteins are potential novel drug targets for treating schistosomiasis. Here we characterize two novel serotonin transporter gene transcripts, SmSERT-A and SmSERT-B, from S.mansoni. Southern blot analysis shows that the two mRNAs are the products of different alleles of a single SmSERT gene locus. The two SmSERT forms differ in three amino acid positions near the N-terminus of the protein. Both SmSERTs are expressed in the adult form and in the sporocyst form (infected snails) of the parasite, but are absent from all other stages of the parasite's complex life cycle. Heterologous expression of the two cDNAs in mammalian cells resulted in saturable, sodium-dependent serotonin transport activity with an apparent affinity for serotonin comparable to that of the human serotonin transporter. Although the two SmSERTs are pharmacologically indistinguishable from each other, efflux experiments reveal notably higher substrate selectivity for serotonin compared with their mammalian counterparts. Several well-established substrates for human SERT including (+/-)MDMA, S-(+)amphetamine, RU 24969, and m-CPP are not transported by SmSERTs, underscoring the higher selectivity of the schistosomal isoforms. Voltage-clamp recordings of SmSERT substrate-elicited currents confirm the substrate selectivity observed in efflux experiments and suggest that it may be possible to exploit the electrogenic nature of SmSERT to screen for compounds that target the parasite in vivo.
Collapse
|
32
|
Andersen J, Kristensen AS, Bang-Andersen B, Strømgaard K. Recent advances in the understanding of the interaction of antidepressant drugs with serotonin and norepinephrine transporters. Chem Commun (Camb) 2009:3677-92. [PMID: 19557250 DOI: 10.1039/b903035m] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The biogenic monoamine transporters are integral membrane proteins that perform active transport of extracellular dopamine, serotonin and norepinephrine into cells. These transporters are targets for therapeutic agents such as antidepressants, as well as addictive substances such as cocaine and amphetamine. Seminal advances in the understanding of the structure and function of this transporter family have recently been accomplished by structural studies of a bacterial transporter, as well as medicinal chemistry and pharmacological studies of mammalian transporters. This feature article focuses on antidepressant drugs that act on the serotonin and/or the norepinephrine transporters. Specifically, we focus on structure-activity relationships of these drugs with emphasis on relationships between their molecular properties and the current knowledge of transporter structure.
Collapse
Affiliation(s)
- Jacob Andersen
- Department of Medicinal Chemistry, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark.
| | | | | | | |
Collapse
|
33
|
Association of changes in norepinephrine and serotonin transporter expression with the long-term behavioral effects of antidepressant drugs. Neuropsychopharmacology 2009; 34:1467-81. [PMID: 18923402 PMCID: PMC2727703 DOI: 10.1038/npp.2008.183] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Previous work has shown that repeated desipramine treatment causes downregulation of the norepinephrine transporter (NET) and persistent antidepressant-like effects on behavior, ie effects observed 2 days after discontinuation of drug treatment when acute effects are minimized. The present study examined whether this mechanism generalizes to other antidepressants and also is evident for the serotonin transporter (SERT). Treatment of rats for 14 days with 20 mg/kg per day protriptyline or 7.5 mg/kg per day sertraline reduced NET and SERT expression, respectively, in cerebral cortex and hippocampus; these treatments also induced a persistent antidepressant-like effect on forced-swim behavior. Increased serotonergic neurotransmission likely mediated the behavioral effect of sertraline, as it was blocked by inhibition of serotonin synthesis with p-chlorophenylalanine; a parallel effect was observed previously for desipramine and noradrenergic neurotransmission. Treatment with 20 mg/kg per day reboxetine for 42, but not 14, days reduced NET expression; antidepressant-like effects on behavior were observed for both treatment durations. Treatment for 14 days with 70 mg/kg per day venlafaxine, which inhibits both the NET and SERT, or 10 mg/kg per day phenelzine, a monoamine oxidase inhibitor, produced antidepressant-like effects on behavior without altering NET or SERT expression. For all drugs tested, reductions of NET and SERT protein were not accompanied by reduced NET or SERT mRNA in locus coeruleus or dorsal raphe nucleus, respectively. Overall, the present results suggest an important, though not universal, role for NET and SERT regulation in the long-term behavioral effects of antidepressants. Understanding the mechanisms underlying transporter regulation in vivo may suggest novel targets for the development of antidepressant drugs.
Collapse
|
34
|
Exposure to methamidophos at adulthood elicits depressive-like behavior in mice. Neurotoxicology 2009; 30:471-8. [DOI: 10.1016/j.neuro.2009.01.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2008] [Revised: 12/19/2008] [Accepted: 01/24/2009] [Indexed: 11/18/2022]
|
35
|
Frederick AL, Stanwood GD. Drugs, biogenic amine targets and the developing brain. Dev Neurosci 2009; 31:7-22. [PMID: 19372683 DOI: 10.1159/000207490] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2008] [Accepted: 09/08/2008] [Indexed: 01/12/2023] Open
Abstract
Defects in the development of the brain have a profound impact on mature brain functions and underlying psychopathology. Classical neurotransmitters and neuromodulators, such as dopamine, serotonin, norepinephrine, acetylcholine, glutamate and GABA, have pleiotropic effects during brain development. In other words, these molecules produce multiple diverse effects to serve as regulators of distinct cellular functions at different times in neurodevelopment. These systems are impacted upon by abuse of a variety of illicit drugs, neurotherapeutics and environmental contaminants. In this review, we describe the impact of drugs and chemicals on brain formation and function in animal models and in human populations, highlighting sensitive periods and effects that may not emerge until later in life.
Collapse
Affiliation(s)
- Aliya L Frederick
- Neuroscience Graduate Program, Vanderbilt University, Nashville, TN 37232-6600, USA
| | | |
Collapse
|
36
|
Martin RS, Henningsen RA, Suen A, Apparsundaram S, Leung B, Jia Z, Kondru RK, Milla ME. Kinetic and thermodynamic assessment of binding of serotonin transporter inhibitors. J Pharmacol Exp Ther 2008; 327:991-1000. [PMID: 18801948 DOI: 10.1124/jpet.108.142307] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Several serotonin reuptake inhibitors are in clinical use for treatment of depression and anxiety disorders. However, to date, reported pharmacological differentiation of these ligands has focused mainly on their equilibrium binding affinities for the serotonin transporter. This study takes a new look at antidepressant binding modes using radioligand binding assays with [(3)H]S-citalopram to determine equilibrium and kinetic rate constants across multiple temperatures. The observed dissociation rate constants at 26 degrees C fall into a narrow range for all molecules. Conversely, association rate constants generally decreased with increasing equilibrium binding affinities. Consistent with this, the measured activation energy for S-citalopram association was relatively large (19.5 kcal . mol(-1)), suggesting conformational change upon ligand binding. For most of the drugs, including citalopram, the enthalpy (DeltaH(O)) and entropy (-TDeltaS(O)) contributions to reaction energetics were determined by van't Hoff analyses to be roughly equivalent (25-75% DeltaG(O)) and to correlate (positively for enthalpy) with the polar surface area of the drug. However, the binding of the drug fluvoxamine was predominantly entropically driven. When these data are considered in the context of the physicochemical properties of these ligands, two distinct binding modes can be proposed. The citalopram-type binding mode probably uses a polar binding pocket that allows charged or polar interactions between ligand and receptor with comparatively small loss in enthalpy due to dehydration. The fluvoxamine-type binding mode is fueled by energy released upon burying hydrophobic ligand moieties into a binding pocket that is flexible enough to suffer minimal loss in entropy from conformational constraint.
Collapse
Affiliation(s)
- Renee S Martin
- Departments of Biochemical Pharmacology, Roche Pharmaceuticals, Palo Alto CA 94304, USA.
| | | | | | | | | | | | | | | |
Collapse
|
37
|
Linder AE, Diaz J, Ni W, Szasz T, Burnett R, Watts SW. Vascular reactivity, 5-HT uptake, and blood pressure in the serotonin transporter knockout rat. Am J Physiol Heart Circ Physiol 2008; 294:H1745-52. [PMID: 18263707 DOI: 10.1152/ajpheart.91415.2007] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The handling of serotonin [5-hydroxytryptamine (5-HT)] depends on the serotonin transporter (SERT). A SERT knockout (KO) rat is a useful model to test the hypothesis that SERT is the primary mechanism for arterial 5-HT uptake and to investigate the impact of SERT removal on blood pressure. Wild-type (WT) and KO rats were used to measure 5-HT content (plasma, raphe, aorta, carotid, and mesenteric artery), aortic isometric contraction, and blood pressure. HPLC supported the lack of circulating 5-HT in plasma (ng/ml plasma, WT, 310 +/- 96; and KO, 1.0 +/- 0.5; P < 0.05). Immunohistochemistry and Western blot analyses validated the presence of the SERT protein in the WT rats and a lesser expression in the KO rat. The aorta isolated from KO rats had a normal contraction to phenylephrine and norepinephrine and a normal relaxation to the endothelium-dependent agonist acetylcholine compared with the aorta from WT. In contrast, the potency of 5-HT was increased in the aorta from KO rats compared with WT rats [-log EC(50) (M); WT, 5.71 +/- 0.08; and KO, 6.7 +/- 0.18] and maximum contraction was reduced [%phenylephrine (10 muM) contraction, WT, 113 +/- 6%; and KO, 52 +/- 12%]. 5-HT uptake was reduced but not abolished in arteries of the KO compared with the WT rats. Diurnal mean arterial blood pressure, heart rate, and locomotor activity level of the KO rats were similar to the WT rats. These data suggest that there are other mechanisms of 5-HT uptake in the arteries of the rat and that although the absence of circulating 5-HT and/or SERT function sensitizes arteries to 5-HT, SERT dysfunction does not impair normal blood pressure.
Collapse
Affiliation(s)
- A Elizabeth Linder
- Dept. of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48824-1317, USA
| | | | | | | | | | | |
Collapse
|
38
|
Livesay DR, Kidd PD, Eskandari S, Roshan U. Assessing the ability of sequence-based methods to provide functional insight within membrane integral proteins: a case study analyzing the neurotransmitter/Na+ symporter family. BMC Bioinformatics 2007; 8:397. [PMID: 17941992 PMCID: PMC2194793 DOI: 10.1186/1471-2105-8-397] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2007] [Accepted: 10/17/2007] [Indexed: 01/09/2023] Open
Abstract
Background Efforts to predict functional sites from globular proteins is increasingly common; however, the most successful of these methods generally require structural insight. Unfortunately, despite several recent technological advances, structural coverage of membrane integral proteins continues to be sparse. ConSequently, sequence-based methods represent an important alternative to illuminate functional roles. In this report, we critically examine the ability of several computational methods to provide functional insight within two specific areas. First, can phylogenomic methods accurately describe the functional diversity across a membrane integral protein family? And second, can sequence-based strategies accurately predict key functional sites? Due to the presence of a recently solved structure and a vast amount of experimental mutagenesis data, the neurotransmitter/Na+ symporter (NSS) family is an ideal model system to assess the quality of our predictions. Results The raw NSS sequence dataset contains 181 sequences, which have been aligned by various methods. The resultant phylogenetic trees always contain six major subfamilies are consistent with the functional diversity across the family. Moreover, in well-represented subfamilies, phylogenetic clustering recapitulates several nuanced functional distinctions. Functional sites are predicted using six different methods (phylogenetic motifs, two methods that identify subfamily-specific positions, and three different conservation scores). A canonical set of 34 functional sites identified by Yamashita et al. within the recently solved LeuTAa structure is used to assess the quality of the predictions, most of which are predicted by the bioinformatic methods. Remarkably, the importance of these sites is largely confirmed by experimental mutagenesis. Furthermore, the collective set of functional site predictions qualitatively clusters along the proposed transport pathway, further demonstrating their utility. Interestingly, the various prediction schemes provide results that are predominantly orthogonal to each other. However, when the methods do provide overlapping results, specificity is shown to increase dramatically (e.g., sites predicted by any three methods have both accuracy and coverage greater than 50%). Conclusion The results presented herein clearly establish the viability of sequence-based bioinformatic strategies to provide functional insight within the NSS family. As such, we expect similar bioinformatic investigations will streamline functional investigations within membrane integral families in the absence of structure.
Collapse
Affiliation(s)
- Dennis R Livesay
- Department of Computer Science and Bioinformatics Research Center, University of North Carolina at Charlotte, Charlotte, NC 28262, USA.
| | | | | | | |
Collapse
|
39
|
Chorbov VM, Lobos EA, Todorov AA, Heath AC, Botteron KN, Todd RD. Relationship of 5-HTTLPR genotypes and depression risk in the presence of trauma in a female twin sample. Am J Med Genet B Neuropsychiatr Genet 2007; 144B:830-3. [PMID: 17455215 DOI: 10.1002/ajmg.b.30534] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Several studies have implicated an insertion/deletion polymorphism in the promoter region of the serotonin transporter gene (SLC6A4; 5-HTT) in the development of mood disorders. In the present study of a sample of 247 young adult female twins from Missouri, we examine whether this polymorphism interacts with the effect of adverse life events to increase risk for developing depression. We found a significant interaction between the number of high-activity L(A) alleles and exposure to trauma (OR = 1.70, P < 0.0001). This differs from previous reports, in that the higher activity genotypes (L(A)/L(A), L(A)/S, L(A)/L(G)), rather than the low activity genotypes (S/S, S/L(G), L(G)/L(G)), are associated with an increased incidence of major depressive disease (MDD) in the presence of environmental trauma.
Collapse
Affiliation(s)
- Vesselin M Chorbov
- Department of Psychiatry, Washington University School of Medicine, Saint Louis, Missouri 63110, USA
| | | | | | | | | | | |
Collapse
|
40
|
Hwang LC, Chang CJ, Liu HH, Kao HC, Lee SY, Jan ML, Chen CC. Imaging the availability of serotonin transporter in rat brain with 123I-ADAM and small-animal SPECT. Nucl Med Commun 2007; 28:615-21. [PMID: 17625383 DOI: 10.1097/mnm.0b013e32825a67cb] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Imaging serotonin transporters during antidepressant treatment in small animals is a useful tool for preclinical study during drug development. In this work, we aimed to demonstrate the feasibility of using 123I-ADAM and small-animal SPECT to monitor serotonin transporter availabilities in rat brains prior to and after administration of a selective serotonin re-uptake inhibitor. METHODS Male Sprague-Dawley rats with and without administration of citalopram (4 mg x kg body weight) were examined in this study. During the process rat brains were scanned using a double-headed microSPECT system equipped with pinhole collimators. SPECT tomographic images and X-ray computed tomography (CT) were acquired after introducing 123I-ADAM via the tail vein. The 123I-ADAM specific binding was assessed by SPECT/CT fused image to draw regions of interest in the midbrain and cerebellum. Ex-vivo autoradiography was carried out as a parallel investigation to validate the SPECT technique. RESULTS SPECT images displayed specific binding ratio in midbrain to be 0.91+/-0.30 averaged from three rats. Drug occupancies (95.47+/-1.56)% were shown after administration of citalopram in a dosage of 4 mg x kg. CONCLUSION This study demonstrated that the serotonin transporter availability during antidepressant treatment in small animals can be assessed semi-quantitatively by using 123I-ADAM and SPECT.
Collapse
Affiliation(s)
- Li-Chung Hwang
- Radiation A, Institute of Nuclear Energy Research, Taoyuan, Taiwan.
| | | | | | | | | | | | | |
Collapse
|
41
|
Oya S, Choi SR, Kung MP, Kung HF. 5-Chloro-2-(2'-((dimethylamino)methyl)-4'-iodophenylthio)benzenamine: a new serotonin transporter ligand. Nucl Med Biol 2007; 34:129-39. [PMID: 17307121 PMCID: PMC1892637 DOI: 10.1016/j.nucmedbio.2006.12.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2006] [Revised: 12/02/2006] [Accepted: 12/13/2006] [Indexed: 11/20/2022]
Abstract
Two novel ligands with 4' substitution on the Phenyl Ring B of biphenylthiol, 5-chloro-2-(2'-((dimethylamino)methyl)-4'-iodophenylthio)benzenamine (7) and 2-(2'-((dimethylamino)methyl)-4'-methoxyphenylthio)-5-iodobenzenamine (8), were prepared and tested as potential serotonin transporter (SERT) imaging agents. The new ligands displayed extremely high binding affinities to SERT (K(i)=0.22+/-0.09 and 0.11+/-0.04 nM, respectively), with very low binding affinities to dopamine and norepinephrine transporters (K(i)>1000 nM). The corresponding [(125)I]7 and [(125)I]8 were successfully prepared from tri-n-butyltin derivatives. They showed good brain uptakes and prolonged retention after intravenous injection in rats (brain uptake was 1.77% and 0.98% dose/g for [(125)I]7, and 0.92% and 0.29% dose/g for [(125)I]8, at 2 and 120 min, respectively). Significantly, [(125)I]7 showed excellent uptake and prolonged retention in the hypothalamus, where SERT concentration was highest. The hypothalamus/cerebellum (HY/CB) ratios (target/background ratios) were 4.24, 7.10, 8.24 and 12.6 at 2, 4, 6 and 12 h, respectively. The HY/CB ratios for [(125)I]8 were 3.97, 5.57 and 5.06 at 1, 2 and 4 h, respectively. Adding the 4'-iodo group to the Phenyl Ring B of Compound (7) appeared to reduce the rate of clearance from the brain, and kinetics favored uptake and retention in the hypothalamus. The localization of [(125)I]7 in the hypothalamus region in the rat brain could be blocked by pretreatment with (+)McN5652, escitalopram and ADAM (2), which are all selective SERT ligands (at 2 mg/kg iv, 5 min pretreatment). Ex vivo autoradiograms of rat brain sections (at 4 h after intravenous injection of [(125)I]7) showed intense labeling in regions of the brain known to have high SERT density. The excellent selective uptake and retention in the hypothalamus region suggest that [(123)I]7 is a potential lead compound for developing new imaging agents targeting SERT-binding sites with single-photon emission computed tomography.
Collapse
Affiliation(s)
- Shunichi Oya
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | | | | | | |
Collapse
|
42
|
Marin P, Chanrion B, Bockaert J. [When two molecules involved in the regulation of mood meet: mutual modulation of the serotonin transporter and neuronal NO-synthase]. Med Sci (Paris) 2007; 23:554-5. [PMID: 17502079 DOI: 10.1051/medsci/2007235554] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
43
|
Chanrion B, Mannoury la Cour C, Bertaso F, Lerner-Natoli M, Freissmuth M, Millan MJ, Bockaert J, Marin P. Physical interaction between the serotonin transporter and neuronal nitric oxide synthase underlies reciprocal modulation of their activity. Proc Natl Acad Sci U S A 2007; 104:8119-24. [PMID: 17452640 PMCID: PMC1876581 DOI: 10.1073/pnas.0610964104] [Citation(s) in RCA: 143] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The spatiotemporal regulation of neurotransmitter transporters involves proteins that interact with their intracellular domains. Using a proteomic approach, we identified several proteins that interact with the C terminus of the serotonin transporter (SERT). These included neuronal nitric oxide synthase (nNOS), a PSD-95/Disc large/ZO-1 (PDZ) domain-containing protein recruited by the atypical PDZ binding motif of SERT. Coexpression of nNOS with SERT in HEK293 cells decreased SERT cell surface localization and 5-hydroxytryptamine (5-HT) uptake. These effects were absent in cells transfected with SERT mutated in its PDZ motif to prevent physical association with nNOS, and 5-HT uptake was unaffected by activation or inhibition of nNOS enzymatic activity. 5-HT uptake into brain synaptosomes was increased in both nNOS-deficient and wild-type mice i.v. injected with a membrane-permeant peptidyl mimetic of SERT C terminus, which disrupted interaction between SERT and nNOS, suggesting that nNOS reduces SERT activity in vivo. Furthermore, treating cultured mesencephalic neurons with the mimetic peptide similarly increased 5-HT uptake. Reciprocally, indicating that 5-HT uptake stimulates nNOS activity, NO production was enhanced on exposure of cells cotransfected with nNOS and SERT to 5-HT. This effect was abolished by 5-HT uptake inhibitors and absent in cells expressing SERT mutated in its PDZ motif. In conclusion, physical association between nNOS and SERT provides a molecular substrate for their reciprocal functional modulation. In addition to showing that nNOS controls cell surface localization of SERT, these findings provide evidence for regulation of cellular signaling (NO production) by a substrate-carrying transporter.
Collapse
Affiliation(s)
- B. Chanrion
- *Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5203, F-34094 Montpellier, France
- Institut National de la Santé de la Recherche Médicale, U661, F-34094 Montpellier, France
- Université de Montpellier I, F-34094 Montpellier, France
- Université Montpellier II, F-34094 Montpellier, France
- Institut de Génomique Fonctionnelle, Département de Neurobiologie, 141 Rue de la Cardonille, F-34094 Montpellier Cedex 5, France
- I.d.R Servier, 78290 Croissy, Paris, France; and
| | | | - F. Bertaso
- *Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5203, F-34094 Montpellier, France
- Institut National de la Santé de la Recherche Médicale, U661, F-34094 Montpellier, France
- Université de Montpellier I, F-34094 Montpellier, France
- Université Montpellier II, F-34094 Montpellier, France
- Institut de Génomique Fonctionnelle, Département de Neurobiologie, 141 Rue de la Cardonille, F-34094 Montpellier Cedex 5, France
| | - M. Lerner-Natoli
- *Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5203, F-34094 Montpellier, France
- Institut National de la Santé de la Recherche Médicale, U661, F-34094 Montpellier, France
- Université de Montpellier I, F-34094 Montpellier, France
- Université Montpellier II, F-34094 Montpellier, France
- Institut de Génomique Fonctionnelle, Département de Neurobiologie, 141 Rue de la Cardonille, F-34094 Montpellier Cedex 5, France
| | - M. Freissmuth
- **Institute of Pharmacology, University of Vienna, Wahringer Strasse 13a, A-1090 Vienna, Austria
| | - M. J. Millan
- I.d.R Servier, 78290 Croissy, Paris, France; and
| | - J. Bockaert
- *Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5203, F-34094 Montpellier, France
- Institut National de la Santé de la Recherche Médicale, U661, F-34094 Montpellier, France
- Université de Montpellier I, F-34094 Montpellier, France
- Université Montpellier II, F-34094 Montpellier, France
- Institut de Génomique Fonctionnelle, Département de Neurobiologie, 141 Rue de la Cardonille, F-34094 Montpellier Cedex 5, France
- To whom correspondence should be addressed. E-mail:
| | - P. Marin
- *Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5203, F-34094 Montpellier, France
- Institut National de la Santé de la Recherche Médicale, U661, F-34094 Montpellier, France
- Université de Montpellier I, F-34094 Montpellier, France
- Université Montpellier II, F-34094 Montpellier, France
- Institut de Génomique Fonctionnelle, Département de Neurobiologie, 141 Rue de la Cardonille, F-34094 Montpellier Cedex 5, France
| |
Collapse
|
44
|
Ho MK, Tyndale RF. Overview of the pharmacogenomics of cigarette smoking. THE PHARMACOGENOMICS JOURNAL 2007; 7:81-98. [PMID: 17224913 DOI: 10.1038/sj.tpj.6500436] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cigarette smoking increases the risk of numerous health problems, including cancer, cardiovascular and pulmonary disorders, making smoking the leading cause of preventable death in the world. Nicotine is primarily responsible for the highly addictive properties of cigarettes. Although the majority of smokers express a desire to quit, few are successful in doing so. Twin and family studies have indicated substantial genetic contributions to smoking behaviors. One major research focus has been to elucidate the specific genes involved; this has been accomplished primarily through genome-wide linkage analyses and candidate gene association studies. Much attention has focused on genes involved in the neurotransmitter pathways for the brain reward system and genes altering nicotine metabolism. This paper reviews the current state of knowledge for genetic factors implicated in smoking behaviors, and examines how genetic variations may affect therapeutic outcomes for drugs used to assist smoking cessation.
Collapse
Affiliation(s)
- M K Ho
- Centre for Addiction and Mental Health, Department of Pharmacology, University of Toronto, Toronto, Canada
| | | |
Collapse
|
45
|
Zhou M, Engel K, Wang J. Evidence for significant contribution of a newly identified monoamine transporter (PMAT) to serotonin uptake in the human brain. Biochem Pharmacol 2007; 73:147-54. [PMID: 17046718 PMCID: PMC1828907 DOI: 10.1016/j.bcp.2006.09.008] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2006] [Revised: 09/07/2006] [Accepted: 09/08/2006] [Indexed: 01/20/2023]
Abstract
The high affinity serotonin transporter (SERT) constitutes the principal pathway for removal of serotonin (5-HT) from extracellular fluid of brain, but evidence indicates that other transporters may also be involved in this process. We recently reported the cloning of a novel plasma membrane monoamine transporter (PMAT), which is abundantly expressed in the human brain and avidly transports 5-HT [Engel K, Zhou M, Wang J. Identification and characterization of a novel monoamine transporter in the human brain. J Biol Chem 2004;279:50042-9]. In this study, we evaluated whether PMAT contributes to total human brain uptake of 5-HT using a hybrid depletion approach in Xenopus laevis oocytes. We also examined whether PMAT interacts with selective serotonin reuptake inhibitors (SSRIs) using MDCK cells stably expressing recombinant human PMAT. Microinjection of total human brain poly(A)(+) mRNA into oocytes elicited approximately 2.5-3-fold increase in 5-HT uptake. Pre-hybridization of poly(A)(+) mRNA with PMAT or SERT antisense oligonucleotides significantly reduced mRNA-induced 5-HT uptake. An additive inhibitory effect was observed when poly(A)(+) mRNA was co-hybridized with both PMAT and SERT antisense oligonucleotides. In contrast, mRNA-induced 5-HT uptake was not affected by pre-hybridization with sense oligonucleotides. These data suggest that functional transcripts of PMAT are present in the human brain, and the PMAT transporter may be significantly involved in brain uptake of 5-HT. All five tested SSRIs inhibited PMAT with IC(50) values ranging from 11 to 116 microM, which are much greater than clinically encountered concentrations, suggesting that PMAT activity is minimally affected by SSRI therapies.
Collapse
Affiliation(s)
- Mingyan Zhou
- Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, WA 98195, USA
| | | | - Joanne Wang
- Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, WA 98195, USA
| |
Collapse
|
46
|
Zheng G, Horton DB, Deaciuc AG, Dwoskin LP, Crooks PA. Des-keto lobeline analogs with increased potency and selectivity at dopamine and serotonin transporters. Bioorg Med Chem Lett 2006; 16:5018-21. [PMID: 16905316 PMCID: PMC3934794 DOI: 10.1016/j.bmcl.2006.07.070] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2006] [Accepted: 07/14/2006] [Indexed: 11/26/2022]
Abstract
A series of des-keto lobeline analogs has been synthesized and evaluated for their ability to inhibit the dopamine transporter (DAT) and serotonin transporter (SERT) function and for their affinity for the synaptic vesicle monoamine transporter (VMAT2), as well as for alpha4beta2( *) and alpha7( *) neuronal nicotinic acetylcholine receptors (nAChRs). The enantiomers 8R-hydroxylobel-9-ene (3a) and 10S-hydroxylobel-7-ene (3c) exhibited high potency and selectivity at SERT and DAT, respectively.
Collapse
Affiliation(s)
- Guangrong Zheng
- College of Pharmacy, University of Kentucky, Lexington, KY 40536-0082, USA
| | - David B. Horton
- College of Pharmacy, University of Kentucky, Lexington, KY 40536-0082, USA
| | | | - Linda P. Dwoskin
- College of Pharmacy, University of Kentucky, Lexington, KY 40536-0082, USA
| | - Peter A. Crooks
- College of Pharmacy, University of Kentucky, Lexington, KY 40536-0082, USA
| |
Collapse
|
47
|
Launay JM, Schneider B, Loric S, Da Prada M, Kellermann O. Serotonin transport and serotonin transporter‐mediated antidepressant recognition are controlled by 5‐HT2Breceptor signaling in serotonergic neuronal cells. FASEB J 2006; 20:1843-54. [PMID: 16940156 DOI: 10.1096/fj.06-5724com] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The plasma membrane 5-HT transporter (SERT) is the major protagonist in regulating extracellular 5-HT concentration and constitutes the target of drugs used to treat a host of metabolic and psychiatric disorders. The exact mechanisms sustaining SERT function still remain elusive. The present work exploits the properties of the 1C11 neuroectodermal progenitor, which acquires, upon 4 days of differentiation, a functional SERT within an integrated serotonergic phenotype to investigate regulatory mechanisms involved in SERT onset and functions. We show that poly(A) addition precedes SERT mRNA translation on day 2 of the serotonergic program. The newly translated transporter molecules immediately bind cocaine. Day 4 must be awaited to monitor antidepressant recognition and 5-HT uptake. Because external 5-HT reduces both 5-HT transport and SERT antidepressant binding, we identify 5-HT(2B) receptors as key players in controlling the overall 5-HT transport system. In the absence of external 5-HT, 5-HT(2B) receptor coupling to NO production ensures SERT phosphorylation to basal level and maximal 5-HT uptake. In the presence of 5-HT, the 5-HT(2B) receptor-PKC coupling promotes additional phosphorylations of both SERT and Na(+),K(+)-ATPase alpha-subunit, impairing the electrochemical gradient necessary to 5-HT uptake. SERT hyperphosphorylation also affects antidepressant recognition. Finally, such 5-HT(2B) receptor-mediated control of SERT activity operates in primary neurons from raphe nuclei. Altogether, our data shed new light on the 5-HT-driven post-translational modifications involved in the control of SERT activity.
Collapse
MESH Headings
- Animals
- Antidepressive Agents, Tricyclic/pharmacology
- Biological Transport
- Cell Differentiation
- Cell Membrane/drug effects
- Cell Membrane/physiology
- Cells, Cultured
- Frontal Lobe/physiology
- Male
- Mice
- Mice, Inbred BALB C
- Neurons/cytology
- Neurons/drug effects
- Neurons/physiology
- Phosphorylation
- RNA, Messenger/genetics
- Raphe Nuclei/physiology
- Receptor, Serotonin, 5-HT2B/drug effects
- Receptor, Serotonin, 5-HT2B/genetics
- Receptor, Serotonin, 5-HT2B/physiology
- Serotonin/metabolism
- Serotonin/physiology
- Serotonin Plasma Membrane Transport Proteins/genetics
- Serotonin Plasma Membrane Transport Proteins/physiology
- Signal Transduction
Collapse
Affiliation(s)
- Jean-Marie Launay
- Service de Biochimie, Hôpital Lariboisière, Laboratoire de Biologie Cellulaire, Faculté de Pharmacie, Université Paris V, Paris, France.
| | | | | | | | | |
Collapse
|