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Huang Z, Wu J, Guan Y, Wei Y, Xie F, Shen Y. PET/CT study of dopamine transporter (DAT) binding with the triple reuptake inhibitor toludesvenlafaxine in rats and humans. Eur J Nucl Med Mol Imaging 2024; 51:2638-2648. [PMID: 38587645 DOI: 10.1007/s00259-024-06700-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Accepted: 03/19/2024] [Indexed: 04/09/2024]
Abstract
PURPOSE Toludesvenlafaxine is a recently developed antidepressant that belongs to the triple reuptake inhibitor class. Despite the in vitro evidence that toludesvenlafaxine inhibits the reuptake of serotonin (5-HT), norepinephrine (NE) and dopamine (DA), there is no in vivo evidence that toludesvenlafaxine binds to DAT and increases DA level, a mechanism thought to contribute to its favorable clinical performance. METHODS Positron emission tomography/computed tomography (PET/CT) was used to examine the DAT binding capacity in healthy rats and human subjects and microdialysis was used to examine the striatal DA level in rats. [18F]FECNT and [11C]CFT were used as PET/CT radioactive tracer for rat and human studies, respectively. RESULTS In rats, 9 mg/kg of toludesvenlafaxine hydrochloride (i.v.) followed by an infusion of 3 mg/kg via minipump led to the binding rate to striatum DAT at 3.7 - 32.41% and to hypothalamus DAT at 5.91 - 17.52% during the 45 min scanning period. 32 mg/kg oral administration with toludesvenlafaxine hydrochloride significantly increased the striatal DA level with the AUC0 - 180 min increased by 63.9%. In healthy volunteers, 160 mg daily toludesvenlafaxine hydrochloride sustained-release tablets for 4 days led to an average occupancy rates of DAT at 8.04% ± 7.75% and 8.09% ± 7.00%, respectively, in basal ganglion 6 h and 10 h postdose. CONCLUSION These results represent the first to confirm the binding of toludesvenlafaxine to DAT in both rats and humans using PET/CT, and its elevation of brain DA level, which may help understand the unique pharmacological and functional effects of triple reuptake inhibitors such as toludesvenlafaxine. CLINICALTRIALS GOV IDENTIFIERS NCT05905120. Registered 14 June 2023. (retrospectively registered).
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Affiliation(s)
- Zhiwei Huang
- Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Junhao Wu
- Department of Nuclear Medicine & PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Yihui Guan
- Department of Nuclear Medicine & PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Yumei Wei
- Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Fang Xie
- Department of Nuclear Medicine & PET Center, Huashan Hospital, Fudan University, Shanghai, China.
| | - Yifeng Shen
- Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
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Lu J, Huang G, Chang X, Wei B, Sun Y, Yang Z, Zhao Y, Zhao Z, Dong G, Chen J. Effects of Serotonin on Cell Viability, Permeability of Bovine Mammary Gland Epithelial Cells and Their Transcriptome Analysis. Int J Mol Sci 2023; 24:11388. [PMID: 37511146 PMCID: PMC10379418 DOI: 10.3390/ijms241411388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 07/10/2023] [Accepted: 07/11/2023] [Indexed: 07/30/2023] Open
Abstract
Serotonin (5-HT) has been reported to play an important role in mammary gland involution that is defined as the process through which the gland returns to a nonlactating state. However, the overall picture of the regulatory mechanisms of 5-HT and the effects of serotonylation on mammary gland involution still need to be further investigated. The current study aimed to investigate the effects of 5-HT on global gene expression profiles of bovine mammary epithelial cells (MAC-T) and to preliminarily examine whether the serotonylation involved in the mammary gland involution by using Monodansylcadaverine (MDC), a competitive inhibitor of transglutaminase 2. Results showed that a high concentration of 5-HT decreased viability and transepithelial electrical resistance (TEER) in MAC-T cells. Transcriptome analysis indicated that 2477 genes were differentially expressed in MAC-T cells treated with 200 μg/mL of 5-HT compared with the control group, and the Notch, p53, and PI3K-Akt signaling pathways were enriched. MDC influenced 5-HT-induced MAC-T cell death, fatty acid synthesis, and the formation and disruption of tight junctions. Overall, a high concentration of 5-HT is able to accelerate mammary gland involution, which may be regulated through the Notch, p53, and PI3K-Akt signaling pathways. Serotonylation is involved in bovine mammary gland involution.
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Affiliation(s)
- Jie Lu
- College of Animal Science and Technology, Southwest University, Chongqing 400715, China
- Chongqing Key Laboratory of Herbivore Science, Chongqing 400715, China
| | - Guohao Huang
- College of Animal Science and Technology, Southwest University, Chongqing 400715, China
- Chongqing Key Laboratory of Herbivore Science, Chongqing 400715, China
| | - Xuan Chang
- College of Animal Science and Technology, Southwest University, Chongqing 400715, China
- Chongqing Key Laboratory of Herbivore Science, Chongqing 400715, China
| | - Bingni Wei
- College of Animal Science and Technology, Southwest University, Chongqing 400715, China
- Chongqing Key Laboratory of Herbivore Science, Chongqing 400715, China
| | - Yawang Sun
- College of Animal Science and Technology, Southwest University, Chongqing 400715, China
- Chongqing Key Laboratory of Herbivore Science, Chongqing 400715, China
| | - Zhengguo Yang
- College of Animal Science and Technology, Southwest University, Chongqing 400715, China
- Chongqing Key Laboratory of Herbivore Science, Chongqing 400715, China
| | - Yongju Zhao
- College of Animal Science and Technology, Southwest University, Chongqing 400715, China
- Chongqing Key Laboratory of Herbivore Science, Chongqing 400715, China
| | - Zhongquan Zhao
- College of Animal Science and Technology, Southwest University, Chongqing 400715, China
- Chongqing Key Laboratory of Herbivore Science, Chongqing 400715, China
| | - Guozhong Dong
- College of Animal Science and Technology, Southwest University, Chongqing 400715, China
- Chongqing Key Laboratory of Herbivore Science, Chongqing 400715, China
| | - Juncai Chen
- College of Animal Science and Technology, Southwest University, Chongqing 400715, China
- Chongqing Key Laboratory of Herbivore Science, Chongqing 400715, China
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Hartmann S, Parrino L, Ensrud K, Stone KL, Redline S, Clark SR, Baumert M. Association between psychotropic medication and sleep microstructure: evidence from large population studies. J Clin Sleep Med 2023; 19:581-589. [PMID: 36546402 PMCID: PMC9978436 DOI: 10.5664/jcsm.10394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 11/03/2022] [Accepted: 11/04/2022] [Indexed: 12/24/2022]
Abstract
STUDY OBJECTIVES To assess the association between psychotropic medications and sleep microstructure in large community-based cohorts of older people. METHODS We analyzed overnight polysomnograms of 381 women from the Study of Osteoporotic Fractures (SOF) and 2,657 men from the Osteoporotic Fractures in Men Sleep Study (MrOS), who either used no psychotropic medication (n = 2,819), only benzodiazepines (n = 112), or only selective serotonin reuptake inhibitors (SSRI) (n = 107). Sleep microstructure (cyclic alternating pattern, CAP) was compared between the no medication group and psychotropic medication groups using the Mann-Whitney U test. Significant differences were investigated using multivariable linear regression adjusted for confounders. RESULTS CAP rate, arousal index, apnea-hypopnea index, and the frequency of slow, low-amplitude electroencephalography activation phases were significantly lower in MrOS participants using benzodiazepines than participants not taking psychotropic medication. SSRI users in MrOS experienced no altered sleep microstructure compared to those with no psychotropic use. SOF participants using benzodiazepines did not show similar associations with sleep microstructure. However, SSRI users from SOF had a significantly higher frequency of rapid, high-amplitude electroencephalography activation phases (A2 + 3) and periodic limb-movement index than participants not taking psychotropic medication. Multivariable linear regression adjusted for demographic, lifestyle, mood disorders, and health variables indicated additional significant associations between benzodiazepine usage and CAP rate and A2 + 3 index, respectively, in older men, and between CAP rate and SSRI usage in older women. CONCLUSIONS We identified significant associations between sleep microstructure and psychotropic drugs in MrOS and SOF, highlighting the importance of comprehensive sleep analysis, including CAP. Our results may improve understanding of the differences in sleep-wake mechanisms based on psychotropic usage. CLINICAL TRIAL REGISTRATION Registry: ClinicalTrials.gov; Title: Outcomes of Sleep Disorders in Older Men; Identifier: NCT00070681; URL: https://clinicaltrials.gov/ct2/show/record/NCT00070681. CITATION Hartmann S, Parrino L, Ensrud K, et al. Association between psychotropic medication and sleep microstructure: evidence from large population studies. J Clin Sleep Med. 2023;19(3):581-589.
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Affiliation(s)
- Simon Hartmann
- The University of Adelaide, School of Electrical and Electronic Engineering, Adelaide, South Australia, Australia
- The University of Adelaide, Discipline of Psychiatry, Adelaide Medical School, Adelaide, South Australia, Australia
| | - Liborio Parrino
- Sleep Disorders Center, Department of Neurology, University of Parma, Parma, Emilia-Romagna, Italy
| | - Kristine Ensrud
- Center for Chronic Disease Outcomes Research, Veterans Affairs Medical Center, Minneapolis, Minnesota
- Department of Medicine and Division of Epidemiology, University of Minnesota, Minneapolis, Minnesota
| | - Katie L. Stone
- California Pacific Medical Center Research Institute, San Francisco, California
| | - Susan Redline
- Departments of Medicine and Neurology, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts
| | - Scott R. Clark
- The University of Adelaide, Discipline of Psychiatry, Adelaide Medical School, Adelaide, South Australia, Australia
| | - Mathias Baumert
- The University of Adelaide, School of Electrical and Electronic Engineering, Adelaide, South Australia, Australia
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Faster Serotonin Clearance in CA3 Region of Hippocampus and Antidepressant-like Effect of Decynium-22 in Juvenile Mice Are Putatively Linked to Increased Plasma Membrane Monoamine Transporter Function: Implications for Efficacy of Antidepressants in Juveniles. Cells 2022; 11:cells11152454. [PMID: 35954298 PMCID: PMC9368098 DOI: 10.3390/cells11152454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 08/02/2022] [Accepted: 08/04/2022] [Indexed: 11/17/2022] Open
Abstract
Selective serotonin reuptake inhibitors (SSRIs) are less efficacious in treating depression in children than in adults. SSRIs block serotonin uptake via the high-affinity, low-capacity serotonin transporter. However, the low-affinity, high-capacity organic cation transporter 3 (OCT3) and plasma membrane monoamine transporter (PMAT) are emerging as important players in serotonin uptake. We hypothesized that OCT3 and/or PMAT are functionally upregulated in juveniles, thereby buffering SSRIs' ability to enhance serotonergic neurotransmission. Unlike in adult mice, we found the OCT/PMAT blocker, decynium-22, to have standalone antidepressant-like effects in juveniles. Using in vivo high-speed chronoamperometry, we found that juveniles clear serotonin from the CA3 region of the hippocampus ~2-fold faster than adult mice. Cell density did not differ between ages, suggesting that faster serotonin clearance in juveniles is unrelated to faster diffusion through the extracellular matrix. Western blot and immunohistochemistry showed that juvenile mice have modestly greater expression of PMAT than adults, whereas OCT3 expression in the CA3 region of the hippocampus was similar between ages. Together, these data suggest that faster serotonin clearance and antidepressant-like effects of decynium-22 in juvenile mice may be due to functionally upregulated PMAT. Faster serotonin clearance via PMAT in juveniles may contribute to reduced therapeutic efficacy of SSRIs in children relative to adults.
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Dagher M, Perrotta KA, Erwin SA, Hachisuka A, Iyer R, Masmanidis SC, Yang H, Andrews AM. Optogenetic Stimulation of Midbrain Dopamine Neurons Produces Striatal Serotonin Release. ACS Chem Neurosci 2022; 13:946-958. [PMID: 35312275 PMCID: PMC9040469 DOI: 10.1021/acschemneuro.1c00715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Targeting neurons with light-driven opsins is widely used to investigate cell-specific responses. We transfected midbrain dopamine neurons with the excitatory opsin Chrimson. Extracellular basal and stimulated neurotransmitter levels in the dorsal striatum were measured by microdialysis in awake mice. Optical activation of dopamine cell bodies evoked terminal dopamine release in the striatum. Multiplexed analysis of dialysate samples revealed that the evoked dopamine was accompanied by temporally coupled increases in striatal 3-methoxytyramine, an extracellular dopamine metabolite, and in serotonin. We investigated a mechanism for dopamine-serotonin interactions involving striatal dopamine receptors. However, the evoked serotonin associated with optical stimulation of dopamine neurons was not abolished by striatal D1- or D2-like receptor inhibition. Although the mechanisms underlying the coupling of striatal dopamine and serotonin remain unclear, these findings illustrate advantages of multiplexed measurements for uncovering functional interactions between neurotransmitter systems. Furthermore, they suggest that the output of optogenetic manipulations may extend beyond opsin-expressing neuronal populations.
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Affiliation(s)
- Merel Dagher
- Molecular Toxicology Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, United States
| | - Katie A. Perrotta
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, United States
| | - Sara A. Erwin
- Molecular Toxicology Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, United States
| | - Ayaka Hachisuka
- Department of Neurobiology, University of California, Los Angeles, Los Angeles, CA 90095, United States
| | - Rahul Iyer
- Department of Electrical Engineering, University of California, Los Angeles, Los Angeles, CA, 94720
| | - Sotiris C. Masmanidis
- Department of Neurobiology, University of California, Los Angeles, Los Angeles, CA 90095, United States
- Neuroscience Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, United States
- California Nanosystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, United States
| | - Hongyan Yang
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience & Human Behavior, and Hatos Center for Neuropharmacology, University of California, Los Angeles, Los Angeles, CA 90095, United States
| | - Anne M. Andrews
- Molecular Toxicology Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, United States
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, United States
- Neuroscience Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, United States
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience & Human Behavior, and Hatos Center for Neuropharmacology, University of California, Los Angeles, Los Angeles, CA 90095, United States
- California Nanosystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, United States
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Zhao C, Cheung KM, Huang IW, Yang H, Nakatsuka N, Liu W, Cao Y, Man T, Weiss PS, Monbouquette HG, Andrews AM. Implantable aptamer-field-effect transistor neuroprobes for in vivo neurotransmitter monitoring. SCIENCE ADVANCES 2021; 7:eabj7422. [PMID: 34818033 PMCID: PMC8612678 DOI: 10.1126/sciadv.abj7422] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
While tools for monitoring in vivo electrophysiology have been extensively developed, neurochemical recording technologies remain limited. Nevertheless, chemical communication via neurotransmitters plays central roles in brain information processing. We developed implantable aptamer–field-effect transistor (FET) neuroprobes for monitoring neurotransmitters. Neuroprobes were fabricated using high-throughput microelectromechanical system (MEMS) technologies, where 150 probes with shanks of either 150- or 50-μm widths and thicknesses were fabricated on 4-inch Si wafers. Nanoscale FETs with ultrathin (~3 to 4 nm) In2O3 semiconductor films were prepared using sol-gel processing. The In2O3 surfaces were coupled with synthetic oligonucleotide receptors (aptamers) to recognize and to detect the neurotransmitter serotonin. Aptamer-FET neuroprobes enabled femtomolar serotonin detection limits in brain tissue with minimal biofouling. Stimulated serotonin release was detected in vivo. This study opens opportunities for integrated neural activity recordings at high spatiotemporal resolution by combining these aptamer-FET sensors with other types of Si-based implantable probes to advance our understanding of brain function.
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Affiliation(s)
- Chuanzhen Zhao
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Kevin M. Cheung
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - I-Wen Huang
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Hongyan Yang
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, Hatos Center for Neuropharmacology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Nako Nakatsuka
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Wenfei Liu
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Yan Cao
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Tianxing Man
- Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Paul S. Weiss
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Harold G. Monbouquette
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Anne M. Andrews
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, Hatos Center for Neuropharmacology, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Corresponding author.
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Restless legs syndrome affecting the head region: "restless head syndrome". Neurol Sci 2021; 43:2565-2570. [PMID: 34661784 DOI: 10.1007/s10072-021-05667-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 10/14/2021] [Indexed: 10/20/2022]
Abstract
OBJECTIVE Restless legs syndrome (RLS) is a well-established disease that has recently been shown to have variants affecting the arms, face, abdomen, and genital area. To our knowledge, there has been no study reporting on the RLS variant affecting the head region. METHODS The retrospective study reviewed a total of 460 patients who presented to Fırat University Medical School and were diagnosed as having RLS based on the International Restless Legs Syndrome Study Group (IRLSSG) criteria between June 2017 and January 2020. Of these, 18 patients that presented with head-related RLS symptoms (in addition to legs or arms) and four cases that presented with isolated head involvement were included in the study. RESULTS In 15 out of 18 (81.8%) patients, the restless head syndrome was accompanied by restless arm syndrome (RAS). In the remaining four (18.2%) patients, the disease involved the head region alone. The disease initially emerged in a single region in the body and gradually spread to one or multiple other regions in most patients and the symptoms were relieved by head rubbing. Serum iron level was low in 8 (36.4%) patients and normal in 14 (63.6%) patients. All the patients had normal cranial imaging and the symptoms were eliminated after dopaminergic therapy. CONCLUSIONS Although RLS typically involves the legs alone, it may also affect other body parts such as upper extremities, abdomen, face, and genital area. We propose that the novel RLS variant described in the present study could be termed "restless head syndrome."
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De Deurwaerdère P, Chagraoui A, Di Giovanni G. Serotonin/dopamine interaction: Electrophysiological and neurochemical evidence. PROGRESS IN BRAIN RESEARCH 2021; 261:161-264. [PMID: 33785130 DOI: 10.1016/bs.pbr.2021.02.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The interaction between serotonin (5-HT) and dopamine (DA) in the central nervous system (CNS) plays an important role in the adaptive properties of living animals to their environment. These are two modulatory, divergent systems shaping and regulating in a widespread manner the activity of neurobiological networks and their interaction. The concept of one interaction linking these two systems is rather elusive when looking at the mechanisms triggered by these two systems across the CNS. The great variety of their interacting mechanisms is in part due to the diversity of their neuronal origin, the density of their fibers in a given CNS region, the distinct expression of their numerous receptors in the CNS, the heterogeneity of their intracellular signaling pathway that depend on the cellular type expressing their receptors, and the state of activity of neurobiological networks, conditioning the outcome of their mutual influences. Thus, originally conceptualized as inhibition of 5-HT on DA neuron activity and DA neurotransmission, this interaction is nowadays considered as a multifaceted, mutual influence of these two systems in the regulation of CNS functions. These new ways of understanding this interaction are of utmost importance to envision the consequences of their dysfunctions underlined in several CNS diseases. It is also essential to conceive the mechanism of action of psychotropic drugs directly acting on their function including antipsychotic, antidepressant, antiparkinsonian, and drug of abuse together with the development of therapeutic strategies of Alzheimer's diseases, epilepsy, obsessional compulsive disorders. The 5-HT/DA interaction has a long history from the serendipitous discovery of antidepressants and antipsychotics to the future, rationalized treatments of CNS disorders.
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Affiliation(s)
- Philippe De Deurwaerdère
- Centre National de la Recherche Scientifique, Institut des Neurosciences Intégratives et Cognitives d'Aquitaine, UMR 5287, Bordeaux, France.
| | - Abdeslam Chagraoui
- Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Institute for Research and Innovation in Biomedicine of Normandy (IRIB), Normandie University, UNIROUEN, INSERM U1239, Rouen, France; Department of Medical Biochemistry, Rouen University Hospital, Rouen, France
| | - Giuseppe Di Giovanni
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, United Kingdom.
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Murlanova K, Michaelevski I, Kreinin A, Terrillion C, Pletnikov M, Pinhasov A. Link between temperament traits, brain neurochemistry and response to SSRI: insights from animal model of social behavior. J Affect Disord 2021; 282:1055-1066. [PMID: 33601678 DOI: 10.1016/j.jad.2020.11.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/14/2020] [Accepted: 11/01/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND Dominant-submissive relationships depend upon functionality of the neural circuits involving monoaminergic neurotransmission. Behavioral profiles of selectively bred dominant (Dom) and submissive (Sub) mice have been proposed to mimic hyperthymic- or depressive-like temperaments observed in patients with affective disorders. These mice differentially respond to psychotropic agents and stressful stimuli, however, the mechanisms underlying these differences remain unclear. To address these mechanisms, we analyzed the brain monoamine content and responses to paroxetine (PXT) in Dom and Sub mice. METHODS The behavioral effects of PXT (3 mg/kg, single injection) were assessed with the Elevated Plus Maze (EPM) and Forced Swim Test (FST). Monoamine tissue content was analyzed by HPLC-ECD. RESULTS Compared to Dom, Sub mice had decreased levels of serotonin (5-HT) in the brainstem (BS), reduced levels of norepinephrine (NE) in the prefrontal cortex (PFC), hippocampus (HPC), and striatum (STR) and elevated levels of dopamine (DA) in PFC, HPC, STR and BS. In EPM, PXT administration increased locomotion and exploration in Dom mice, with no effect in Sub mice. In FST, PXT disrupted immobility in Dom mice only. The PXT-produced differences in regional monoamine content were strain-dependent and consistent with the behavioral alterations. LIMITATIONS Chronic PXT treatment, in vivo monoamine assays and sex-dependent analysis were out of the scope of this study and will be performed in the future in order to provide an in-depth evaluation of the neurochemical mechanisms underlying temperament-dependent responses to SSRIs. CONCLUSIONS Our findings suggest neurochemical mechanisms that underlie temperament-based response to antidepressant treatment.
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Affiliation(s)
- Kateryna Murlanova
- Department of Molecular Biology, Ariel University, Ariel 4070000, Israel; Department of Psychiatry and Behavioral Sciences and Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA; Department of Physiology and Biophysics, The Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York 14203, USA
| | - Izhak Michaelevski
- Department of Molecular Biology, Ariel University, Ariel 4070000, Israel; Adelson School of Medicine, Ariel University, Ariel 4070000, Israel
| | - Anatoly Kreinin
- Department of Molecular Biology, Ariel University, Ariel 4070000, Israel
| | - Chantelle Terrillion
- Department of Psychiatry and Behavioral Sciences and Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | - Mikhail Pletnikov
- Department of Psychiatry and Behavioral Sciences and Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA; Department of Physiology and Biophysics, The Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York 14203, USA
| | - Albert Pinhasov
- Department of Molecular Biology, Ariel University, Ariel 4070000, Israel; Adelson School of Medicine, Ariel University, Ariel 4070000, Israel.
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Levitan MN, Papelbaum M, Carta MG, Appolinario JC, Nardi AE. Binge Eating Disorder: A 5-Year Retrospective Study on Experimental Drugs. J Exp Pharmacol 2021; 13:33-47. [PMID: 33542663 PMCID: PMC7853418 DOI: 10.2147/jep.s255376] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 01/11/2021] [Indexed: 01/18/2023] Open
Abstract
Binge eating disorder (BED) affects a significant rate of the general population causing a negative impact on their quality of life, weight, and self-esteem. Besides psychological treatments that compose the majority of the studies, pharmaceuticals have contributed to improve a host of clinical parameters, thus being an important component of the treatment. We opted to target the latest results by performing a review of the literature on the pharmacology for BED from the last 5 years. To achieve this goal, the terms: "binge eating disorder" and "treatment" were added to the PubMed database and the website clinicaltrials.gov. At least five drugs were either being tested or had already been recognized to improve BED symptoms - although only lisdexamfetamine is currently approved by the FDA to treat this condition. However, due to a better understanding of BED psychopathology in the last decade, it is notorious that improvement of eating-related symptoms is not the only desired target. Due to the significant comorbidity percentage (30%), weight loss is highly pursued, as well as the amelioration of clinical parameters which highlights the importance of having new agents combining both objectives.
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Affiliation(s)
- Michelle N Levitan
- Psychiatry Institute/Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Eating Disorders Department/Sheba Medical Center, Ramat Gan, Israel
| | | | - Mauro G Carta
- Dipartimento di Scienze Mediche e Sanità Pubblica, Università Degli Studi di Cagliari, Cagliari, Italy
| | - Jose C Appolinario
- Psychiatry Institute/Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Antonio E Nardi
- Psychiatry Institute/Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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11
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Abstract
Inhibitors of Na+/Cl- dependent high affinity transporters for norepinephrine (NE), serotonin (5-HT), and/or dopamine (DA) represent frequently used drugs for treatment of psychological disorders such as depression, anxiety, obsessive-compulsive disorder, attention deficit hyperactivity disorder, and addiction. These transporters remove NE, 5-HT, and/or DA after neuronal excitation from the interstitial space close to the synapses. Thereby they terminate transmission and modulate neuronal behavioral circuits. Therapeutic failure and undesired central nervous system side effects of these drugs have been partially assigned to neurotransmitter removal by low affinity transport. Cloning and functional characterization of the polyspecific organic cation transporters OCT1 (SLC22A1), OCT2 (SLC22A2), OCT3 (SLC22A3) and the plasma membrane monoamine transporter PMAT (SLC29A4) revealed that every single transporter mediates low affinity uptake of NE, 5-HT, and DA. Whereas the organic transporters are all located in the blood brain barrier, OCT2, OCT3, and PMAT are expressed in neurons or in neurons and astrocytes within brain areas that are involved in behavioral regulation. Areas of expression include the dorsal raphe, medullary motoric nuclei, hypothalamic nuclei, and/or the nucleus accumbens. Current knowledge of the transport of monoamine neurotransmitters by the organic cation transporters, their interactions with psychotropic drugs, and their locations in the brain is reported in detail. In addition, animal experiments including behavior tests in wildtype and knockout animals are reported in which the impact of OCT2, OCT3, and/or PMAT on regulation of salt intake, depression, mood control, locomotion, and/or stress effect on addiction is suggested.
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Affiliation(s)
- Hermann Koepsell
- Institute of Anatomy and Cell Biology, University Würzburg, Würzburg, Germany.
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12
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Pak A, Chubykin AA. Cortical Tuning is Impaired After Perceptual Experience in Primary Visual Cortex of Serotonin Transporter-Deficient Mice. Cereb Cortex Commun 2020; 1:tgaa066. [PMID: 33134928 PMCID: PMC7575641 DOI: 10.1093/texcom/tgaa066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 08/27/2020] [Accepted: 09/06/2020] [Indexed: 11/16/2022] Open
Abstract
Serotonin (5-hydroxytryptamine) is crucial for the proper development of neuronal circuits early in life and their refinement throughout adulthood. Its signaling is tightly regulated by the serotonin transporter (SERT), alterations of which were implicated in various neurological and psychiatric disorders. Animal models lacking a functional SERT variant display diverse phenotypes, including increased anxiety, social communication deficits, and altered cortical development. However, it remains unclear how SERT disruption affects sensory processing and experience-dependent learning in adulthood. It has been previously shown that perceptual experience leads to the development of visual familiarity-evoked theta oscillations in mouse V1. Here, we discovered that familiarity-evoked theta oscillations were longer and less stimulus specific in SERT knockout (KO) compared with wild-type (WT) mice. Interestingly, while the overall visual response properties were similar in naive mice, orientation and spatial frequency processing were significantly impaired in SERT KO compared with WT or SERT heterozygous mice following perceptual experience. Our findings shed more light on the mechanism of familiarity-evoked oscillations and highlight the importance of serotonin signaling in perceptual learning.
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Affiliation(s)
- Alexandr Pak
- Department of Biological Sciences, Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
| | - Alexander A Chubykin
- Department of Biological Sciences, Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
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13
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Yip PK, Schmitzberger M, Al-Hasan M, George J, Tripoliti E, Michael-Titus AT, Clayton D, Priestley JV. Serotonin Expression in the Song Circuitry of Adult Male Zebra Finches. Neuroscience 2020; 444:170-182. [PMID: 32590039 DOI: 10.1016/j.neuroscience.2020.06.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 06/14/2020] [Accepted: 06/15/2020] [Indexed: 11/25/2022]
Abstract
Serotonin is an important neurotransmitter of the brain, but its role in song control remains to be fully demonstrated. Using male zebra finches (Taeniopygia guttata) that have song learning and production capabilities, we analysed the serotonin expression levels in the song nuclei and adjacent areas (peri-song nuclei) using immunohistochemistry. Key song nuclei were identified using combinations of Hoechst, choline acetyltransferase, and a neurofilament (NN18) marker in reference to the ZEBrA atlas. Mean serotonin expression was highest in interfacial nucleus (Nif) and lower in the other song nuclei in the following order (in order of highest first): interfacial nucleus (Nif) > Area X > dorsomedial part of the intercollicular nucelus (DM) > robust nucleus of the archistriatum (RA) > lateral magnocellular nucleus of the anterior neostriatum (LMAN) > ventral respiratory group (VRG) > dorsolateral nucleus of the medial thalamus (DLM) > the nucleus HVC (proper name) > tracheosyringeal motor nucleus (nXIIts). However, the mean serotonin expression (in order of highest first) in the peri-song nuclei regions was: peri-DM > peri-nXIIts > supra-peri-HVC > peri-RA > peri-DLM > peri-Area X > infra-peri-HVC > peri-VRG > peri-LMAN > peri-Nif. Interestingly, serotoninergic fibers immunostained for serotonin or the serotonin transporter can be found as a basket-like peri-neuronal structure surrounding cholinergic cell bodies, and appear to form contacts onto dopaminergic neurones. In summary, serotonin fibers are present at discrete song nuclei, and peri-song nuclei regions, which suggest serotonin may have a direct and/or modulatory role in song control.
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Affiliation(s)
- Ping K Yip
- Queen Mary University of London, Barts and The London School of Medicine and Dentistry, Blizard Institute, 4 Newark St, London E1 2AT, UK.
| | - Magdalena Schmitzberger
- Queen Mary University of London, Barts and The London School of Medicine and Dentistry, Blizard Institute, 4 Newark St, London E1 2AT, UK
| | - Mohammed Al-Hasan
- Queen Mary University of London, Barts and The London School of Medicine and Dentistry, Blizard Institute, 4 Newark St, London E1 2AT, UK
| | - Julia George
- Queen Mary University of London, School of Biological and Chemical Sciences, G.E. Fogg Building, Mile End Road, London E1 4NS, UK
| | - Elina Tripoliti
- UCL, Institute of Neurology, Department of Movement and Clinical Neurosciences, 33 Queen Square, London WC1N 3BG, UK
| | - Adina T Michael-Titus
- Queen Mary University of London, Barts and The London School of Medicine and Dentistry, Blizard Institute, 4 Newark St, London E1 2AT, UK
| | - David Clayton
- Queen Mary University of London, School of Biological and Chemical Sciences, G.E. Fogg Building, Mile End Road, London E1 4NS, UK
| | - John V Priestley
- Queen Mary University of London, Barts and The London School of Medicine and Dentistry, Blizard Institute, 4 Newark St, London E1 2AT, UK
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14
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Bharatiya R, Chagraoui A, De Deurwaerdere S, Argiolas A, Melis MR, Sanna F, De Deurwaerdere P. Chronic Administration of Fipronil Heterogeneously Alters the Neurochemistry of Monoaminergic Systems in the Rat Brain. Int J Mol Sci 2020; 21:ijms21165711. [PMID: 32784929 PMCID: PMC7461054 DOI: 10.3390/ijms21165711] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 08/06/2020] [Accepted: 08/06/2020] [Indexed: 12/19/2022] Open
Abstract
Fipronil (FPN), a widely used pesticide for agricultural and non-agricultural pest control, is possibly neurotoxic for mammals. Brain monoaminergic systems, involved in virtually all brain functions, have been shown to be sensitive to numerous pesticides. Here, we addressed the hypothesis that chronic exposure to FPN could modify brain monoamine neurochemistry. FPN (10 mg/kg) was chronically administered for 21 days through oral gavage in rats. Thereafter, the tissue concentrations of dopamine (DA) and its metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid; serotonin (5-HT) and its metabolite, 5-hydroxyindoleacetic acid (5-HIAA); and noradrenaline (NA) were measured in 30 distinct brain regions. FPN significantly decreased DA and its metabolite levels in most striatal territories, including the nucleus accumbens and the substantia nigra (SN). FPN also diminished 5-HT levels in some striatal regions and the SN. The indirect index of the turnovers, DOPAC/DA and 5-HIAA/5-HT ratios, was increased in numerous brain regions. FPN reduced the NA content only in the nucleus accumbens core. Using the Bravais–Pearson test to study the neurochemical organization of monoamines through multiple correlative analyses across the brain, we found fewer correlations for NA, DOPAC/DA, and 5-HIAA/5-HT ratios, and an altered pattern of correlations within and between monoamine systems. We therefore conclude that the chronic administration of FPN in rats induces massive and inhomogeneous changes in the DA and 5-HT systems in the brain.
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Affiliation(s)
- Rahul Bharatiya
- Department of Biomedical Sciences, Section of Neuroscience and Clinical Pharmacology, University of Cagliari, 09100 Cagliari, Italy; (R.B.); (A.A.); (M.R.M.)
- Centre National de la Recherche Scientifique (Unité Mixte de Recherche 5287), 146 rue Léo Saignat, B.P.281, F-33000 Bordeaux CEDEX, France;
| | - Abdeslam Chagraoui
- Neuronal and Neuroendocrine Differentiation and Communication Laboratory, Institute for Research and Innovation in Biomedicine of Normandy (IRIB), Normandie Univ, UNIROUEN, INSERM, U1239, CHU Rouen, 76000 Rouen, France;
- Department of Medical Biochemistry, Rouen University Hospital, 76000 Rouen, France
| | - Salomé De Deurwaerdere
- Centre National de la Recherche Scientifique (Unité Mixte de Recherche 5287), 146 rue Léo Saignat, B.P.281, F-33000 Bordeaux CEDEX, France;
| | - Antonio Argiolas
- Department of Biomedical Sciences, Section of Neuroscience and Clinical Pharmacology, University of Cagliari, 09100 Cagliari, Italy; (R.B.); (A.A.); (M.R.M.)
- Centre of Excellence for the Neurobiology of Addictions, University of Cagliari, 09100 Cagliari, Italy
- Institute of Neuroscience, National Research Council, Cagliari Section, University of Cagliari, 09100 Cagliari, Italy
| | - Maria Rosaria Melis
- Department of Biomedical Sciences, Section of Neuroscience and Clinical Pharmacology, University of Cagliari, 09100 Cagliari, Italy; (R.B.); (A.A.); (M.R.M.)
- Centre of Excellence for the Neurobiology of Addictions, University of Cagliari, 09100 Cagliari, Italy
| | - Fabrizio Sanna
- Department of Biomedical Sciences, Section of Neuroscience and Clinical Pharmacology, University of Cagliari, 09100 Cagliari, Italy; (R.B.); (A.A.); (M.R.M.)
- Correspondence: (F.S.); (P.D.D.); Tel.: +39-070-675-4330 (F.S.); +33-557-571-290 (P.D.D.)
| | - Philippe De Deurwaerdere
- Centre National de la Recherche Scientifique (Unité Mixte de Recherche 5287), 146 rue Léo Saignat, B.P.281, F-33000 Bordeaux CEDEX, France;
- Correspondence: (F.S.); (P.D.D.); Tel.: +39-070-675-4330 (F.S.); +33-557-571-290 (P.D.D.)
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15
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5-HT2C receptor blockade reverses SSRI-associated basal ganglia dysfunction and potentiates therapeutic efficacy. Mol Psychiatry 2020; 25:3304-3321. [PMID: 30120415 PMCID: PMC6378140 DOI: 10.1038/s41380-018-0227-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 07/13/2018] [Accepted: 07/24/2018] [Indexed: 11/09/2022]
Abstract
Serotonin (5-HT) selective reuptake inhibitors (SSRIs) are widely used in the treatment of depression and anxiety disorders, but responsiveness is uncertain and side effects often lead to discontinuation. Side effect profiles suggest that SSRIs reduce dopaminergic (DAergic) activity, but specific mechanistic insight is missing. Here we show in mice that SSRIs impair motor function by acting on 5-HT2C receptors in the substantia nigra pars reticulata (SNr), which in turn inhibits nigra pars compacta (SNc) DAergic neurons. SSRI-induced motor deficits can be reversed by systemic or SNr-localized 5-HT2C receptor antagonism. SSRIs induce SNr hyperactivity and SNc hypoactivity that can also be reversed by systemic 5-HT2C receptor antagonism. Optogenetic inhibition of SNc DAergic neurons mimics the motor deficits due to chronic SSRI treatment, whereas local SNr 5-HT2C receptor antagonism or optogenetic activation of SNc DAergic neurons reverse SSRI-induced motor deficits. Lastly, we find that 5-HT2C receptor antagonism potentiates the antidepressant and anxiolytic effects of SSRIs. Together our findings demonstrate opposing roles for 5-HT2C receptors in the effects of SSRIs on motor function and affective behavior, highlighting the potential benefits of 5-HT2C receptor antagonists for both reduction of motor side effects of SSRIs and augmentation of therapeutic antidepressant and anxiolytic effects.
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16
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Hsu YC, Yang HY, Huang WT, Chen SCC, Lee HS. Use of antidepressants and risks of restless legs syndrome in patients with irritable bowel syndrome: A population-based cohort study. PLoS One 2019; 14:e0220641. [PMID: 31369638 PMCID: PMC6675099 DOI: 10.1371/journal.pone.0220641] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 07/19/2019] [Indexed: 12/12/2022] Open
Abstract
Previous research has suggested an association between antidepressants use and clinical restless legs syndrome (RLS) in patients, but there has never been a single study investigating the risk of RLS in irritable bowel syndrome (IBS) patients treated with antidepressants. Hence, we aimed to explore the association between IBS and RLS and to examine the risk of RLS in IBS patients treated with antidepressants. With the use of the National Health Insurance Research Database of Taiwan, 27,437 adults aged ≥ 20 years with newly diagnosed IBS (ICD-9-CM Code 564.1) and gender- and age-matched 54,874 controls without IBS were enrolled between 2000 and 2012. All patients were followed-up until RLS diagnosis, withdrawal from the National Health Insurance program, or end of 2013. We used the Cox proportional hazards model to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) of RLS. RLS was more prevalent in IBS patients than in the non-IBS group (7.57 versus 3.36 per 10,000 person-years), with an increased risk of RLS (adjusted HR [aHR], 1.91; 95% CI, 1.52-2.40). Multivariate Cox proportional hazards analysis identified older age (age, 51-65 years; aHR, 1.67; 95% CI, 1.09-2.56; and age > 65; aHR, 1.59; 95% CI, 1.02-2.48), hypothyroidism (aHR, 4.24; 95% CI, 1.92-9.37), CAD (aHR, 1.70; 95% CI, 1.17-2.48), and depression (aHR, 3.15; 95% CI, 2.14-4.64) as independent RLS risk factors in IBS patients. In addition, the male SSRIs users were associated with significantly higher risk of RLS (aHR, 3.05 95% CI, 1.34-6.92). Our study showed that the IBS group has higher risk of RLS. Moreover, SSRIs use may increase the risk of RLS in male IBS patients.
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Affiliation(s)
- Yung-Chu Hsu
- Division of Neurology, Department of Internal medicine, Ditmanson Medical Foundation Chia-Yi Christian Hospital, Chia-Yi City, Taiwan
| | - Hsin-Yi Yang
- Clinical Medicine Research Center, Ditmanson Medical Foundation Chia-Yi Christian Hospital, Chia-Yi City, Taiwan
- * E-mail: (HYY); (HSL)
| | - Wan-Ting Huang
- Clinical Medicine Research Center, Ditmanson Medical Foundation Chia-Yi Christian Hospital, Chia-Yi City, Taiwan
| | - Solomon Chih-Cheng Chen
- Department of Pediatrics, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Department of Pediatrics, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Herng-Sheng Lee
- Department of Pathology and Laboratory Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
- * E-mail: (HYY); (HSL)
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17
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Majuri J, Joutsa J, Arponen E, Forsback S, Kaasinen V. Dopamine synthesis capacity correlates with µ-opioid receptor availability in the human basal ganglia: A triple-tracer PET study. Neuroimage 2018; 183:1-6. [PMID: 30077742 DOI: 10.1016/j.neuroimage.2018.07.069] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 07/20/2018] [Accepted: 07/31/2018] [Indexed: 12/16/2022] Open
Abstract
Animal studies have suggested that dopamine and opioid neurotransmitter systems interact in brain regions that are relevant for reward functions, but data in humans are very limited. The interaction is potentially important in disorders affecting these neurotransmitter systems, such as addiction. Here, we investigated whether subcortical μ-opioid receptor (MOR) availability and presynaptic dopamine synthesis capacity are correlated in the healthy human brain or in pathological gamblers (PGs) using positron emission tomography with 6-[18F]fluoro-l-dopa and [11C]carfentanil. The specificity of the findings was further investigated by including a serotonin transporter ligand, [11C]MADAM, as a negative control. Thirteen PG patients and 15 age-, sex- and weight-matched controls underwent the scans. In both groups, presynaptic dopamine synthesis capacity was associated with MOR availability in the putamen, caudate nucleus and globus pallidus. No similar associations were observed between dopamine synthesis capacity and [11C]MADAM binding, supporting a specific interplay between presynaptic dopamine neurotransmission and opioid receptor function in the basal ganglia. Correlations were similar between the groups, suggesting that the dopamine-opioid link is general and unaffected by behavioral addiction. The results provide in vivo human evidence of a connection between endogenous opioid and dopamine signaling in the brain.
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Affiliation(s)
- Joonas Majuri
- Division of Clinical Neurosciences, Turku University Hospital, PO Box 52, FIN-20521, Turku, Finland; Department of Neurology, University of Turku, PO Box 52, FIN-20521, Turku, Finland; Turku PET Centre, University of Turku, PO Box 52, FIN-20521, Turku, Finland.
| | - Juho Joutsa
- Division of Clinical Neurosciences, Turku University Hospital, PO Box 52, FIN-20521, Turku, Finland; Department of Neurology, University of Turku, PO Box 52, FIN-20521, Turku, Finland; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States; Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States
| | - Eveliina Arponen
- Turku PET Centre, University of Turku, PO Box 52, FIN-20521, Turku, Finland
| | - Sarita Forsback
- Turku PET Centre, University of Turku, PO Box 52, FIN-20521, Turku, Finland
| | - Valtteri Kaasinen
- Division of Clinical Neurosciences, Turku University Hospital, PO Box 52, FIN-20521, Turku, Finland; Department of Neurology, University of Turku, PO Box 52, FIN-20521, Turku, Finland; Turku PET Centre, University of Turku, PO Box 52, FIN-20521, Turku, Finland
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18
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Korte-Bouws GAH, van Heesch F, Westphal KGC, Ankersmit LMJ, van Oosten EM, Güntürkün O, Korte SM. Bacterial Lipopolysaccharide Increases Serotonin Metabolism in Both Medial Prefrontal Cortex and Nucleus Accumbens in Male Wild Type Rats, but Not in Serotonin Transporter Knockout Rats. Pharmaceuticals (Basel) 2018; 11:ph11030066. [PMID: 29976854 PMCID: PMC6160917 DOI: 10.3390/ph11030066] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 06/29/2018] [Accepted: 07/02/2018] [Indexed: 11/19/2022] Open
Abstract
It is well known that bacterial lipopolysaccharides (LPS) both increases proinflammatory cytokines and produces sickness behavior, including fatigue and anhedonia (i.e., the inability to experience pleasure). Previously, we have shown that intraperitoneally (i.p.) administered LPS increased extracellular monoamine metabolite levels in the nucleus accumbens (NAc) and medial prefrontal cortex (mPFC), which was completely, or at least partly, prevented by pretreatment with a triple reuptake inhibitor that also blocks the serotonin (5-HT) transporter (SERT). This suggests indirectly, that LPS may enhance SERT transporter activity, and consequently, increase removal of 5-HT from the synaptic cleft, and increase metabolism of 5-HT. In the present study, we focus more specifically on the role of SERT in this increased metabolism by using rats, that differ in SERT expression. Therefore, the effects of an intraperitoneal LPS injection on extracellular concentrations of 5-HT and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) were investigated by in vivo microdialysis in the NAc and mPFC of wild type (SERT+/+), heterozygous (SERT+/−) and knockout (SERT−/−) rats. Here, we show that LPS-induced 5-HIAA formation in male rats, is significantly increased in SERT+/+ rats in both the NAc and mPFC, whereas this increase is partly or totally abolished in SERT+/− and SERT−/− rats, respectively. Thus, the present study supports the hypothesis that systemic LPS in male rats increases SERT function and consequently enhances 5-HT uptake and metabolism in both the NAc and mPFC.
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Affiliation(s)
- Gerdien A H Korte-Bouws
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Faculty of Science, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
| | - Floor van Heesch
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Faculty of Science, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
| | - Koen G C Westphal
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Faculty of Science, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
| | - Lisa M J Ankersmit
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Faculty of Science, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
| | - Edwin M van Oosten
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Faculty of Science, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
| | - Onur Güntürkün
- Department of Biopsychology, Faculty of Psychology, Ruhr-Universität Bochum, Universitätsstraße 150, D-44780 Bochum, Germany.
| | - S Mechiel Korte
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Faculty of Science, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
- Department of Biopsychology, Faculty of Psychology, Ruhr-Universität Bochum, Universitätsstraße 150, D-44780 Bochum, Germany.
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19
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Odabaş FÖ, Uca AU. Is there any association between antidepressants and restless legs syndrome in a large Turkish population receiving mono or combined treatment? A cross-sectional comparative study. PSYCHIAT CLIN PSYCH 2018. [DOI: 10.1080/24750573.2018.1480855] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
Affiliation(s)
- Faruk Ömer Odabaş
- Department of Neurology, Konya Health Application and Research Center, University of Health Sciences, Konya, Turkey
| | - Ali Ulvi Uca
- Department of Neurology, Meram Faculty of Medicine, Necmettin Erbakan University, Konya, Turkey
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20
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Gilman TL, George CM, Vitela M, Herrera-Rosales M, Basiouny MS, Koek W, Daws LC. Constitutive plasma membrane monoamine transporter (PMAT, Slc29a4) deficiency subtly affects anxiety-like and coping behaviours. Eur J Neurosci 2018; 48:10.1111/ejn.13968. [PMID: 29797618 PMCID: PMC6252160 DOI: 10.1111/ejn.13968] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 05/04/2018] [Accepted: 05/14/2018] [Indexed: 12/27/2022]
Abstract
Originally, uptake-mediated termination of monoamine (e.g., serotonin and dopamine) signalling was believed to only occur via high-affinity, low-capacity transporters ("uptake1 ") such as the serotonin or dopamine transporters, respectively. Now, the important contribution of a second low-affinity, high-capacity class of biogenic amine transporters has been recognised, particularly in circumstances when uptake1 transporter function is reduced (e.g., antidepressant treatment). Pharmacologic or genetic reductions in uptake1 function can change locomotor, anxiety-like or stress-coping behaviours. Comparable behavioural investigations into reduced low-affinity, high-capacity transporter function are lacking, in part, due to a current dearth of drugs that selectively target particular low-affinity, high-capacity transporters, such as the plasma membrane monoamine transporter. Therefore, the most direct approach involves constitutive genetic knockout of these transporters. Other groups have reported that knockout of the low-affinity, high-capacity organic cation transporters 2 or 3 alters anxiety-like and stress-coping behaviours, but none have assessed behaviours in plasma membrane monoamine transporter knockout mice. Here, we evaluated adult male and female plasma membrane monoamine transporter wild-type, heterozygous and knockout mice in locomotor, anxiety-like and stress-coping behavioural tests. A mild enhancement of anxiety-related behaviour was noted in heterozygous mice. Active-coping behaviour was modestly and selectively increased in female knockout mice. These subtle behavioural changes support a supplemental role of plasma membrane monoamine transporter in serotonin and dopamine uptake, and suggest sex differences in transporter function should be examined more closely in future investigations.
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Affiliation(s)
- T. Lee Gilman
- Department of Cellular & Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Addiction Research, Treatment & Training Center of Excellence, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Christina M. George
- Department of Cellular & Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Melissa Vitela
- Department of Cellular & Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Myrna Herrera-Rosales
- Department of Cellular & Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Mohamed S. Basiouny
- Department of Cellular & Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Wouter Koek
- Department of Psychiatry, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Lynette C. Daws
- Department of Cellular & Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Addiction Research, Treatment & Training Center of Excellence, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
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21
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De Deurwaerdère P, Di Giovanni G. Serotonergic modulation of the activity of mesencephalic dopaminergic systems: Therapeutic implications. Prog Neurobiol 2016; 151:175-236. [PMID: 27013075 DOI: 10.1016/j.pneurobio.2016.03.004] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 03/13/2016] [Accepted: 03/14/2016] [Indexed: 12/14/2022]
Abstract
Since their discovery in the mammalian brain, it has been apparent that serotonin (5-HT) and dopamine (DA) interactions play a key role in normal and abnormal behavior. Therefore, disclosure of this interaction could reveal important insights into the pathogenesis of various neuropsychiatric diseases including schizophrenia, depression and drug addiction or neurological conditions such as Parkinson's disease and Tourette's syndrome. Unfortunately, this interaction remains difficult to study for many reasons, including the rich and widespread innervations of 5-HT and DA in the brain, the plethora of 5-HT receptors and the release of co-transmitters by 5-HT and DA neurons. The purpose of this review is to present electrophysiological and biochemical data showing that endogenous 5-HT and pharmacological 5-HT ligands modify the mesencephalic DA systems' activity. 5-HT receptors may control DA neuron activity in a state-dependent and region-dependent manner. 5-HT controls the activity of DA neurons in a phasic and excitatory manner, except for the control exerted by 5-HT2C receptors which appears to also be tonically and/or constitutively inhibitory. The functional interaction between the two monoamines will also be discussed in view of the mechanism of action of antidepressants, antipsychotics, anti-Parkinsonians and drugs of abuse.
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Affiliation(s)
- Philippe De Deurwaerdère
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5293, 33076 Bordeaux Cedex, France.
| | - Giuseppe Di Giovanni
- Department of Physiology & Biochemistry, Faculty of Medicine and Surgery, University of Malta, Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, UK.
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Yang H, Sampson MM, Senturk D, Andrews AM. Sex- and SERT-mediated differences in stimulated serotonin revealed by fast microdialysis. ACS Chem Neurosci 2015; 6:1487-501. [PMID: 26167657 DOI: 10.1021/acschemneuro.5b00132] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
In vivo microdialysis is widely used to investigate how neurotransmitter levels in the brain respond to biologically relevant challenges. Here, we combined recent improvements in the temporal resolution of online sampling and analysis for serotonin with a brief high-K(+) stimulus paradigm to study the dynamics of evoked release. We observed stimulated serotonin overflow with high-K(+) pulses as short as 1 min when determined with 2-min dialysate sampling in ventral striatum. Stimulated serotonin levels in female mice during the high estrogen period of the estrous cycle were similar to serotonin levels in male mice. By contrast, stimulated serotonin overflow during the low estrogen period in female mice was increased to levels similar to those in male mice with local serotonin transporter (SERT) inhibition. Stimulated serotonin levels in mice with constitutive loss of SERT were considerably higher yet, pointing to neuroadaptive potentiation of serotonin release. When combined with brief K(+) stimulation, fast microdialysis reveals dynamic changes in extracellular serotonin levels associated with normal hormonal cycles and pharmacologic vs genetic loss of SERT function.
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Affiliation(s)
- Hongyan Yang
- Department of Psychiatry & Biobehavioral Sciences, Hatos Center for Neuropharmacology, Semel Institute for Neuroscience & Human Behavior, David Geffen School of Medicine, ‡Molecular Toxicology Interdepartmental Program, §Department of Chemistry & Biochemistry, and ∥Department of Biostatistics, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, California 90095, United States
| | - Maureen M. Sampson
- Department of Psychiatry & Biobehavioral Sciences, Hatos Center for Neuropharmacology, Semel Institute for Neuroscience & Human Behavior, David Geffen School of Medicine, ‡Molecular Toxicology Interdepartmental Program, §Department of Chemistry & Biochemistry, and ∥Department of Biostatistics, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, California 90095, United States
| | - Damla Senturk
- Department of Psychiatry & Biobehavioral Sciences, Hatos Center for Neuropharmacology, Semel Institute for Neuroscience & Human Behavior, David Geffen School of Medicine, ‡Molecular Toxicology Interdepartmental Program, §Department of Chemistry & Biochemistry, and ∥Department of Biostatistics, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, California 90095, United States
| | - Anne M. Andrews
- Department of Psychiatry & Biobehavioral Sciences, Hatos Center for Neuropharmacology, Semel Institute for Neuroscience & Human Behavior, David Geffen School of Medicine, ‡Molecular Toxicology Interdepartmental Program, §Department of Chemistry & Biochemistry, and ∥Department of Biostatistics, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, California 90095, United States
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Dissociable roles of dopamine and serotonin transporter function in a rat model of negative urgency. Behav Brain Res 2015; 291:201-208. [PMID: 26005123 DOI: 10.1016/j.bbr.2015.05.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 05/12/2015] [Accepted: 05/13/2015] [Indexed: 11/22/2022]
Abstract
Negative urgency is a facet of impulsivity that reflects mood-based rash action and is associated with various maladaptive behaviors in humans. However, the underlying neural mechanisms of negative urgency are not fully understood. Several brain regions within the mesocorticolimbic pathway, as well as the neurotransmitters dopamine (DA) and serotonin (5-HT), have been implicated in impulsivity. Extracellular DA and 5-HT concentrations are regulated by DA transporters (DAT) and 5-HT transporters (SERT); thus, these transporters may be important molecular mechanisms underlying individual differences in negative urgency. The current study employed a reward omission task to model negative urgency in rats. During reward trials, a cue light signaled the non-contingent delivery of one sucrose pellet; immediately following the non-contingent reward, rats responded on a lever to earn sucrose pellets (operant phase). Omission trials were similar to reward trials, except that non-contingent sucrose was omitted following the cue light prior to the operant phase. As expected, contingent responding was higher following omission of expected reward than following delivery of expected reward, thus reflecting negative urgency. Upon completion of behavioral training, Vmax and Km were obtained from kinetic analysis of [(3)H]DA and [(3)H]5-HT uptake using synaptosomes prepared from nucleus accumbens (NAc), dorsal striatum (Str), medial prefrontal cortex (mPFC), and orbitofrontal cortex (OFC) isolated from individual rats. Vmax for DAT in NAc and for SERT in OFC were positively correlated with negative urgency scores. The current findings suggest that mood-based impulsivity (negative urgency) is associated with enhanced DAT function in NAc and SERT function in OFC.
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24
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Behavioral training reverses global cortical network dysfunction induced by perinatal antidepressant exposure. Proc Natl Acad Sci U S A 2015; 112:2233-8. [PMID: 25646455 DOI: 10.1073/pnas.1416582111] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Abnormal cortical circuitry and function as well as distortions in the modulatory neurological processes controlling cortical plasticity have been argued to underlie the origin of autism. Here, we chemically distorted those processes using an antidepressant drug-exposure model to generate developmental neurological distortions like those characteristics expressed in autism, and then intensively trained altered young rodents to evaluate the potential for neuroplasticity-driven renormalization. We found that young rats that were injected s.c. with the antidepressant citalopram from postnatal d 1-10 displayed impaired neuronal repetition-rate following capacity in the primary auditory cortex (A1). With a focus on recovering grossly degraded auditory system processing in this model, we showed that targeted temporal processing deficits induced by early-life antidepressant exposure within the A1 were almost completely reversed through implementation of a simple behavioral training strategy (i.e., a modified go/no-go repetition-rate discrimination task). Degraded parvalbumin inhibitory GABAergic neurons and the fast inhibitory actions that they control were also renormalized by training. Importantly, antidepressant-induced degradation of serotonergic and dopaminergic neuromodulatory systems regulating cortical neuroplasticity was sharply reversed. These findings bear important implications for neuroplasticity-based therapeutics in autistic patients.
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Darna M, Beckmann JS, Gipson CD, Bardo MT, Dwoskin LP. Effect of environmental enrichment on dopamine and serotonin transporters and glutamate neurotransmission in medial prefrontal and orbitofrontal cortex. Brain Res 2014; 1599:115-25. [PMID: 25536304 DOI: 10.1016/j.brainres.2014.12.034] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 12/10/2014] [Accepted: 12/14/2014] [Indexed: 01/27/2023]
Abstract
Recent studies have reported that rats raised in an enriched condition (EC) have decreased dopamine transporter (DAT) function and expression in medial prefrontal cortex (mPFC), as well as increased d-amphetamine-induced glutamate release in nucleus accumbens compared to rats raised in an isolated condition (IC). In these previous studies, DAT function and expression were evaluated using mPFC pooled from four rats for each condition to obtain kinetic parameters due to sparse DAT expression in mPFC. In contrast, accumbal glutamate release was determined using individual rats. The current study extends the previous work and reports on the optimization of DAT and serotonin transporter (SERT) functional assays, as well as cell surface expression assays using both mPFC and orbitofrontal cortex (OFC) from individual EC or IC rats. In addition, the effect of d-amphetamine on glutamate release in mPFC and OFC of EC and IC rats was determined using in vivo microdialysis. Results show that environmental enrichment decreased maximal transport velocity (Vmax) for [(3)H]dopamine uptake in mPFC, but increased Vmax for [(3)H]dopamine uptake in OFC. Corresponding changes in DAT cell surface expression were not found. In contrast, Vmax for [(3)H]serotonin uptake and cellular localization of SERT in mPFC and OFC were not different between EC and IC rats. Further, acute d-amphetamine (2mg/kg, s.c.) increased extracellular glutamate concentrations in mPFC of EC rats only and in OFC of IC rats only. Overall, these results suggest that enrichment produces long-lasting alterations in mPFC and OFC DAT function via a trafficking-independent mechanism, as well as differential glutamate release in mPFC and OFC. Rearing-induced modulation of DAT function and glutamate release in prefrontal cortical subregions may contribute to the known protective effects of enrichment on drug abuse vulnerability.
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Affiliation(s)
- Mahesh Darna
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA
| | - Joshua S Beckmann
- Department of Psychology, University of Kentucky, Lexington, KY 40536, USA
| | - Cassandra D Gipson
- Department of Psychology, University of Kentucky, Lexington, KY 40536, USA; Department of Neurosciences, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Michael T Bardo
- Department of Psychology, University of Kentucky, Lexington, KY 40536, USA
| | - Linda P Dwoskin
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA.
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Huertas A, Wessinger WD, Kucheryavykh YV, Sanabria P, Eaton MJ, Skatchkov SN, Rojas LV, Maldonado-Martínez G, Inyushin MY. Quinine enhances the behavioral stimulant effect of cocaine in mice. Pharmacol Biochem Behav 2014; 129:26-33. [PMID: 25482328 DOI: 10.1016/j.pbb.2014.11.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 11/25/2014] [Accepted: 11/29/2014] [Indexed: 11/20/2022]
Abstract
The Na(+)-dependent dopamine transporter (DAT) is primarily responsible for regulating free dopamine (DA) concentrations in the brain by participating in the majority of DA uptake; however, other DA transporters may also participate, especially if cocaine or other drugs of abuse compromise DAT. Recently, such cocaine-insensitive low-affinity mono- and poly-amine OCT transporters were described in astrocytes which use DA as a substrate. These transporters are from a different transporter family and while insensitive to cocaine, they are specifically blocked by quinine and some steroids. Quinine is inexpensive and is often found in injected street drugs as an "adulterant". The present study was designed to determine the participation of OCTs in cocaine dependent behavioral and physiological changes in mice. Using FVB mice we showed, that daily single injections of quinine (10 mg/kg, i.p.) co-administered with cocaine (15 mg/kg, i.p.) for 10 days significantly enhanced cocaine-induced locomotor behavioral sensitization. Quinine had no significant effect on the time course of behavioral activation. In astrocytes from the ventral tegmental area of mice, transporter currents of quinine-sensitive monoamine transporters were also augmented after two weeks of cocaine administration. The importance of low-affinity high-capacity transporters for DA clearance is discussed, explaining the known ability of systemically administered DAT inhibitors to anomalously increase DA clearance.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Mikhail Y Inyushin
- Universidad Central del Caribe, School of Medicine, P.O. Box 60-327, Bayamón 00960-6032, Puerto Rico.
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Fox MA, Panessiti MG, Moya PR, Tolliver TJ, Chen K, Shih JC, Murphy DL. Mutations in monoamine oxidase (MAO) genes in mice lead to hypersensitivity to serotonin-enhancing drugs: implications for drug side effects in humans. THE PHARMACOGENOMICS JOURNAL 2013; 13:551-7. [PMID: 22964922 PMCID: PMC3562558 DOI: 10.1038/tpj.2012.35] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Revised: 07/18/2012] [Accepted: 07/23/2012] [Indexed: 12/16/2022]
Abstract
A possible side effect of serotonin-enhancing drugs is the serotonin syndrome, which can be lethal. Here we examined possible hypersensitivity to two such drugs, the serotonin precursor 5-hydroxy-L-tryptophan (5-HTP) and the atypical opioid tramadol, in mice lacking the genes for both monoamine oxidase A (MAOA) and MAOB. MAOA/B-knockout (KO) mice displayed baseline serotonin syndrome behaviors, and these behavioral responses were highly exaggerated following 5-HTP or tramadol versus baseline and wild-type (WT) littermates. Compared with MAOA/B-WT mice, baseline tissue serotonin levels were increased ∼2.6-3.9-fold in MAOA/B-KO mice. Following 5-HTP, serotonin levels were further increased ∼4.5-6.2-fold in MAOA/B-KO mice. These exaggerated responses are in line with the exaggerated responses following serotonin-enhancing drugs that we previously observed in mice lacking the serotonin transporter (SERT). These findings provide a second genetic mouse model suggestive of possible human vulnerability to the serotonin syndrome in individuals with lesser-expressing MAO or SERT polymorphisms that confer serotonergic system changes.
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Affiliation(s)
- MA Fox
- Laboratory of Clinical Science (LCS), National Institute of Mental Health, NIH, Bethesda, MD, USA
| | - MG Panessiti
- Laboratory of Clinical Science (LCS), National Institute of Mental Health, NIH, Bethesda, MD, USA
| | - PR Moya
- Laboratory of Clinical Science (LCS), National Institute of Mental Health, NIH, Bethesda, MD, USA
| | - TJ Tolliver
- Laboratory of Clinical Science (LCS), National Institute of Mental Health, NIH, Bethesda, MD, USA
| | - K Chen
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - JC Shih
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
- Department of Cell and Neurobiology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - DL Murphy
- Laboratory of Clinical Science (LCS), National Institute of Mental Health, NIH, Bethesda, MD, USA
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Gardier AM. Antidepressant activity: contribution of brain microdialysis in knock-out mice to the understanding of BDNF/5-HT transporter/5-HT autoreceptor interactions. Front Pharmacol 2013; 4:98. [PMID: 23964240 PMCID: PMC3737470 DOI: 10.3389/fphar.2013.00098] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 07/17/2013] [Indexed: 12/31/2022] Open
Abstract
Why antidepressants vary in terms of efficacy is currently unclear. Despite the leadership of selective serotonin reuptake inhibitors (SSRIs) in the treatment of depression, the precise neurobiological mechanisms involved in their therapeutic action are poorly understood. A better knowledge of molecular interactions between monoaminergic system, pre- and post-synaptic partners, brain neuronal circuits and regions involved may help to overcome limitations of current treatments and identify new therapeutic targets. Intracerebral in vivo microdialysis (ICM) already provided important information about the brain mechanism of action of antidepressants first in anesthetized rats in the early 1990s, and since then in conscious wild-type or knock-out mice. The principle of ICM is based on the balance between release of neurotransmitters (e.g., monoamines) and reuptake by selective transporters [e.g., serotonin transporter for serotonin 5-hydroxytryptamine (5-HT)]. Complementary to electrophysiology, this technique reflects pre-synaptic monoamines release and intrasynaptic events corresponding to ≈80% of whole brain tissue content. The inhibitory role of serotonergic autoreceptors infers that they limit somatodendritic and nerve terminal 5-HT release. It has been proposed that activation of 5-HT1A and 5-HT1B receptor sub-types limits the antidepressant-like activity of SSRIs. This hypothesis is based partially on results obtained in ICM experiments performed in naïve, non-stressed rodents. The present review will first remind the principle and methodology of ICM performed in mice. The crucial need of developing animal models that display anxiety and depression-like behaviors, neurochemical and brain morphological phenotypes reminiscent of these mood disorders in humans, will be underlined. Recently developed genetic mouse models have been generated to independently manipulate 5-HT1A auto and heteroreceptors and ICM helped to clarify the role of the pre-synaptic component, i.e., by measuring extracellular levels of neurotransmitters in serotonergic nerve terminal regions and raphe nuclei. Finally, we will summarize main advantages of using ICM in mice through recent examples obtained in knock-outs (drug infusion through the ICM probe allows the search of a correlation between changes in extracellular neurotransmitter levels and antidepressant-like activity) or alternatives (infusion of a small-interfering RNA suppressing receptor functions in the mouse brain). We will also focus this review on post-synaptic components such as brain-derived neurotrophic factor in adult hippocampus that plays a crucial role in the neurogenic and anxiolytic/antidepressant-like activity of chronic SSRI treatment. Limitations of ICM will also be considered.
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Affiliation(s)
- Alain M Gardier
- EA 3544 "Pharmacologie des troubles anxio-dépressifs et Neurogenèse", Faculté de Pharmacie, Université Paris-Sud Chatenay-Malabry, France
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29
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Kang HH, Wang CH, Chen HC, Li IH, Cheng CY, Liu RS, Huang WS, Shiue CY, Ma KH. Investigating the effects of noise-induced hearing loss on serotonin transporters in rat brain using 4-[18F]-ADAM/small animal PET. Neuroimage 2013; 75:262-269. [DOI: 10.1016/j.neuroimage.2012.06.049] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 06/08/2012] [Accepted: 06/26/2012] [Indexed: 01/10/2023] Open
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Safratowich BD, Lor C, Bianchi L, Carvelli L. Amphetamine activates an amine-gated chloride channel to generate behavioral effects in Caenorhabditis elegans. J Biol Chem 2013; 288:21630-7. [PMID: 23775081 DOI: 10.1074/jbc.m113.484139] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Amphetamine is a highly addictive psychostimulant, which is thought to generate its effects by promoting release of dopamine through reverse activation of dopamine transporters. However, some amphetamine-mediated behaviors persist in dopamine transporter knock-out animals, suggesting the existence of alternative amphetamine targets. Here we demonstrate the identification of a novel amphetamine target by showing that in Caenorhabditis elegans, a large fraction of the behavioral effects of amphetamine is mediated through activation of the amine-gated chloride channel, LGC-55. These findings bring to light alternative pathways engaged by amphetamine, and urge rethinking of the molecular mechanisms underlying the effects of this highly-addictive psychostimulant.
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Affiliation(s)
- Bryan D Safratowich
- Department of Pharmacology, Physiology, and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota 58202-9037, USA
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31
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Li RWS, Yang C, Kwan YW, Chan SW, Lee SMY, Leung GPH. Involvement of organic cation transporter-3 and plasma membrane monoamine transporter in serotonin uptake in human brain vascular smooth muscle cells. Front Pharmacol 2013; 4:14. [PMID: 23407616 PMCID: PMC3569667 DOI: 10.3389/fphar.2013.00014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Accepted: 01/25/2013] [Indexed: 02/01/2023] Open
Abstract
The serotonin (5-HT) uptake system is supposed to play a crucial part in vascular functions by “fine-tuning” the local concentration of 5-HT in the vicinity of 5-HT2 receptors in vascular smooth muscle cells. In this study, the mechanism of 5-HT uptake in human brain vascular smooth muscle cells (HBVSMCs) was investigated. [3H]5-HT uptake in HBVSMCs was Na+-independent. Kinetic analyses of [3H]5-HT uptake in HBVSMCs revealed a Km of 50.36 ± 10.2 mM and a Vmax of 1033.61 ± 98.86 pmol/mg protein/min. The specific serotonin re-uptake transporter (SERT) inhibitor citalopram, the specific norepinephrine transporter (NET) inhibitor desipramine, and the dopamine transporter (DAT) inhibitor GBR12935 inhibited 5-HT uptake in HBVSMCs with IC50 values of 97.03 ± 40.10, 10.49 ± 5.98, and 2.80 ± 1.04 μM, respectively. These IC50 values were 100-fold higher than data reported by other authors, suggesting that those inhibitors were not blocking their corresponding transporters. Reverse transcription-polymerase chain reaction results demonstrated the presence of mRNA for organic cation transporter (OCT)-3 and plasma membrane monoamine transporter (PMAT), but the absence of OCT-1, OCT-2, SERT, NET, and DAT. siRNA knockdown of OCT-3 and PMAT specifically attenuated 5-HT uptake in HBVSMCs. It is concluded that 5-HT uptake in HBVSMCs was mediated predominantly by a low-affinity and Na+-independent mechanism. The most probable candidates are OCT-3 and PMAT, but not the SERT.
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Affiliation(s)
- Rachel W S Li
- Department of Pharmacology and Pharmacy, The University of Hong Kong Pokfulam, Hong Kong
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32
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Daws LC, Koek W, Mitchell NC. Revisiting serotonin reuptake inhibitors and the therapeutic potential of "uptake-2" in psychiatric disorders. ACS Chem Neurosci 2013; 4:16-21. [PMID: 23336039 DOI: 10.1021/cn3001872] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Accepted: 10/25/2012] [Indexed: 01/11/2023] Open
Abstract
Depression is among the most common psychiatric disorders, and in many patients a disorder for which available medications provide suboptimal or no symptom relief. The most commonly prescribed class of antidepressants, the selective serotonin reuptake inhibitors (SSRIs), are thought to act by increasing extracellular serotonin in brain by blocking its uptake via the high-affinity serotonin transporter (SERT). However, the relative lack of therapeutic efficacy of SSRIs has brought into question the utility of increasing extracellular serotonin for the treatment of depression. In this Viewpoint, we discuss why increasing extracellular serotonin should not be written off as a therapeutic strategy. We describe how "uptake-2" transporters may explain the relative lack of therapeutic efficacy of SSRIs, as well as why "uptake-2" transporters might be useful therapeutic targets.
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Affiliation(s)
- Lynette C. Daws
- Departments of †Physiology, ‡Psychiatry, and §Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229,
United States
| | - Wouter Koek
- Departments of †Physiology, ‡Psychiatry, and §Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229,
United States
| | - Nathan C. Mitchell
- Departments of †Physiology, ‡Psychiatry, and §Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229,
United States
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33
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Maloney SE, Rieger MA, Dougherty JD. Identifying essential cell types and circuits in autism spectrum disorders. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2013; 113:61-96. [PMID: 24290383 DOI: 10.1016/b978-0-12-418700-9.00003-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Autism spectrum disorder (ASD) is highly genetic in its etiology, with potentially hundreds of genes contributing to risk. Despite this heterogeneity, these disparate genetic lesions may result in the disruption of a limited number of key cell types or circuits-information which could be leveraged for the design of therapeutic interventions. While hypotheses for cellular disruptions can be identified by postmortem anatomical analysis and expression studies of ASD risk genes, testing these hypotheses requires the use of animal models. In this review, we explore the existing evidence supporting the contribution of different cell types to ASD, specifically focusing on rodent studies disrupting serotonergic, GABAergic, cerebellar, and striatal cell types, with particular attention to studies of the sufficiency of specific cellular disruptions to generate ASD-related behavioral abnormalities. This evidence suggests multiple cellular routes can create features of the disorder, though it is currently unclear if these cell types converge on a final common circuit. We hope that in the future, systematic studies of cellular sufficiency and genetic interaction will help to classify patients into groups by type of cellular disruptions which suggest tractable therapeutic targets.
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Affiliation(s)
- Susan E Maloney
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, USA; Department of Psychiatry, Washington University School of Medicine, St. Louis, Missouri, USA
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Weng SJ, Shiue CY, Huang WS, Cheng CY, Huang SY, Li IH, Tao CC, Chou TK, Liao MH, Chang YP, Ma KH. PET imaging of serotonin transporters with 4-[18F]-ADAM in a Parkinsonian rat model. Cell Transplant 2012; 22:1295-305. [PMID: 23127756 DOI: 10.3727/096368912x658683] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
This study was undertaken to address the effects of fetal mesencephalic tissue transplantation on the serotonin system in a rat model of Parkinson's disease (PD) while also investigating the usefulness of 4-[18F]-ADAM (a serotonin transporter imaging agent) coupled with micro-PET for imaging serotonin transporters (SERTs). A PD model was induced by unilateral injection of 6-hydroxydopamine (6-OHDA) into the right medial forebrain bundle of the nigrostriatal pathway, while cell transplantation was performed via intrastriatal injection of mesencephalic brain tissue dissected from embryonic (E14) rats. The 4-[18F]-ADAM/micro-PET scanning was performed following both 6-OHDA lesioning and transplantation. Immunohistochemistry (IHC) studies were also performed following the final PET scan, and the results were compared to show a 17-43% decrease in the specific uptake ratio (SUR) and a 23-52% decrease in serotonin transporter immunoreactivity (SERT-ir) within various brain regions on the lesioned side. The number of methamphetamine-induced rotations also decreased significantly at the 4th week postgraft. In addition, striatal SUR and the SERT-ir levels were restored to 77% and 83% 5 weeks postgraft. These results suggest that Parkinson's disease also affects the serotonergic system, while both the dopaminergic and serotonergic systems can be partially restored in a rat model of PD after E14 mesencephalic tissue transplantation. In addition, we have also determined that 4-[18F]-ADAM/micro-PET can be used to detect serotonergic neuron loss, monitor the progress of Parkinson's disease, and oversee the effectiveness of therapy.
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Affiliation(s)
- Shao-Ju Weng
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
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35
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Pang RD, Holschneider DP, Miller JD. Circadian rhythmicity in serotonin transporter knockout mice. Life Sci 2012; 91:365-368. [PMID: 22884802 DOI: 10.1016/j.lfs.2012.07.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Revised: 06/25/2012] [Accepted: 07/16/2012] [Indexed: 10/28/2022]
Abstract
AIMS Serotonin transporter knockout (5-HTT KO) mice exhibit elevated basal extracellular serotonin, increased depressive-like behaviors and increased rapid eye movement sleep. Because abnormalities of circadian rhythms are associated with mood disorders, we tested the hypothesis that 5-HTT KO mice would have altered circadian rhythmicity. MAIN METHODS Homecage locomotor activity was recorded in wild-type (WT) and KO mice under a standard 12:12 light-dark cycle. After 4weeks of recording, mice received a one-hour light pulse at circadian time (CT) 14 and then were kept under constant darkness for 3weeks. KEY FINDINGS There were no significant differences in amplitude, period, acrophase or total home cage locomotor activity between WT and KO mice during the 12:12 light-dark cycle or during constant darkness. The mean phase delay to a CT 14 light pulse was significantly attenuated in KO compared to WT mice. SIGNIFICANCE Acute increases in serotonin have been reported to attenuate photic phase shifts. The current study demonstrates that this effect is maintained in the face of a lifelong absence of 5-HTT.
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Affiliation(s)
- Raina D Pang
- Graduate Program in Neuroscience, University of Southern California, United States.
| | - Daniel P Holschneider
- Graduate Program in Neuroscience, University of Southern California, United States; Department of Psychiatry and Behavioral Science, University of Southern California, United States; Department of Neurology, University of Southern California, United States; Department of Biomedical Engineering, University of Southern California, United States; Department of Cell and Neurobiology, University of Southern California, United States
| | - Joseph D Miller
- Department of Cell and Neurobiology, University of Southern California, United States
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Lau T, Schloss P. Differential regulation of serotonin transporter cell surface expression. ACTA ACUST UNITED AC 2012. [DOI: 10.1002/wmts.10] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Chronic 5-HT transporter blockade reduces DA signaling to elicit basal ganglia dysfunction. J Neurosci 2011; 31:15742-50. [PMID: 22049417 DOI: 10.1523/jneurosci.2989-11.2011] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Serotonin (5-HT)-selective reuptake inhibitors (SSRIs) are widely administered for the treatment of depression, anxiety, and other neuropsychiatric disorders, but response rates are low, and side effects often lead to discontinuation. Side effect profiles suggest that SSRIs inhibit dopaminergic activity, but mechanistic insight remains scarce. Here we show that in mice, chronic 5-HT transporter (5-HTT) blockade during adulthood but not during development impairs basal ganglia-dependent behaviors in a dose-dependent and reversible fashion. Furthermore, chronic 5-HTT blockade reduces striatal dopamine (DA) content and metabolism. A causal relationship between reduced DA signaling and impaired basal ganglia-dependent behavior is indicated by the reversal of behavioral deficits through L-DOPA administration. Our data suggest that augmentation of DA signaling would reduce side effects and increase efficacies of SSRI-based therapy.
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Hagino Y, Takamatsu Y, Yamamoto H, Iwamura T, Murphy DL, Uhl GR, Sora I, Ikeda K. Effects of MDMA on Extracellular Dopamine and Serotonin Levels in Mice Lacking Dopamine and/or Serotonin Transporters. Curr Neuropharmacol 2011; 9:91-5. [PMID: 21886569 PMCID: PMC3137209 DOI: 10.2174/157015911795017254] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Revised: 04/17/2010] [Accepted: 05/26/2010] [Indexed: 11/22/2022] Open
Abstract
3,4-Methylendioxymethamphetamine (MDMA) has both stimulatory and hallucinogenic properties which make its psychoactive effects unique and different from those of typical psychostimulant and hallucinogenic agents. The present study investigated the effects of MDMA on extracellular dopamine (DAex) and serotonin (5-HTex) levels in the striatum and prefrontal cortex (PFC) using in vivo microdialysis techniques in mice lacking DA transporters (DAT) and/or 5-HT transporters (SERT). subcutaneous injection of MDMA (3, 10 mg/kg) significantly increased striatal DAex in wild-type mice, SERT knockout mice, and DAT knockout mice, but not in DAT/SERT double-knockout mice. The MDMA-induced increase in striatal DAex in SERT knockout mice was significantly less than in wildtype mice. In the PFC, MDMA dose-dependently increased DAex levels in wildtype, DAT knockout, SERT knockout and DAT/SERT double-knockout mice to a similar extent. In contrast, MDMA markedly increased 5-HTex in wildtype and DAT knockout mice and slightly increased 5-HTex in SERT-KO and DAT/SERT double-knockout mice. The results confirm that MDMA acts at both DAT and SERT and increases DAex and 5-HTex.
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Affiliation(s)
- Y Hagino
- Division of Psychobiology, Tokyo Institute of Psychiatry, Tokyo 156-8585, Japan
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Pang RD, Wang Z, Klosinski LP, Guo Y, Herman DH, Celikel T, Dong HW, Holschneider DP. Mapping functional brain activation using [14C]-iodoantipyrine in male serotonin transporter knockout mice. PLoS One 2011; 6:e23869. [PMID: 21886833 PMCID: PMC3160305 DOI: 10.1371/journal.pone.0023869] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Accepted: 07/27/2011] [Indexed: 02/07/2023] Open
Abstract
Background Serotonin transporter knockout mice have been a powerful tool in understanding the role played by the serotonin transporter in modulating physiological function and behavior. However, little work has examined brain function in this mouse model. We tested the hypothesis that male knockout mice show exaggerated limbic activation during exposure to an emotional stressor, similar to human subjects with genetically reduced transcription of the serotonin transporter. Methodology/Principal Findings Functional brain mapping using [14C]-iodoantipyrine was performed during recall of a fear conditioned tone. Regional cerebral blood flow was analyzed by statistical parametric mapping from autoradiographs of the three-dimensionally reconstructed brains. During recall, knockout mice compared to wild-type mice showed increased freezing, increased regional cerebral blood flow of the amygdala, insula, and barrel field somatosensory cortex, decreased regional cerebral blood flow of the ventral hippocampus, and conditioning-dependent alterations in regional cerebral blood flow in the medial prefrontal cortex (prelimbic, infralimbic, and cingulate). Anxiety tests relying on sensorimotor exploration showed a small (open field) or paradoxical effect (marble burying) of loss of the serotonin transporter on anxiety behavior, which may reflect known abnormalities in the knockout animal's sensory system. Experiments evaluating whisker function showed that knockout mice displayed impaired whisker sensation in the spontaneous gap crossing task and appetitive gap cross training. Conclusions This study is the first to demonstrate altered functional activation in the serotonin transporter knockout mice of critical nodes of the fear conditioning circuit. Alterations in whisker sensation and functional activation of barrel field somatosensory cortex extend earlier reports of barrel field abnormalities, which may confound behavioral measures relying on sensorimotor exploration.
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Affiliation(s)
- Raina D. Pang
- Graduate Program in Neuroscience, University of Southern California, Los Angeles, California, United States of America
| | - Zhuo Wang
- Department of Psychiatry and Behavioral Science, University of Southern California, Los Angeles, California, United States of America
| | - Lauren P. Klosinski
- Graduate Program in Neuroscience, University of Southern California, Los Angeles, California, United States of America
| | - Yumei Guo
- Department of Psychiatry and Behavioral Science, University of Southern California, Los Angeles, California, United States of America
| | - David H. Herman
- Graduate Program in Neuroscience, University of Southern California, Los Angeles, California, United States of America
| | - Tansu Celikel
- Graduate Program in Neuroscience, University of Southern California, Los Angeles, California, United States of America
- Department of Cell and Neurobiology, University of Southern California, Los Angeles, California, United States of America
| | - Hong Wei Dong
- Department of Neurology, School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Daniel P. Holschneider
- Graduate Program in Neuroscience, University of Southern California, Los Angeles, California, United States of America
- Department of Psychiatry and Behavioral Science, University of Southern California, Los Angeles, California, United States of America
- Department of Neurology, University of Southern California, Los Angeles, California, United States of America
- Biomedical Engineering, University of Southern California, Los Angeles, California, United States of America
- Department of Cell and Neurobiology, University of Southern California, Los Angeles, California, United States of America
- * E-mail:
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Larsen MB, Sonders MS, Mortensen OV, Larson GA, Zahniser NR, Amara SG. Dopamine transport by the serotonin transporter: a mechanistically distinct mode of substrate translocation. J Neurosci 2011; 31:6605-15. [PMID: 21525301 PMCID: PMC3107525 DOI: 10.1523/jneurosci.0576-11.2011] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Revised: 03/04/2011] [Accepted: 03/10/2011] [Indexed: 01/23/2023] Open
Abstract
The serotonin transporter (SERT) is the principal mechanism for terminating serotonin (5-HT) signals in the nervous system and is a site of action for a variety of psychoactive drugs including antidepressants, amphetamines, and cocaine. Here we show that human SERTs (hSERTs) and rat SERTs are capable of robust dopamine (DA) uptake through a process that differs mechanistically from 5-HT transport in several unanticipated ways. DA transport by hSERT has a higher maximum velocity than 5-HT transport, requires significantly higher Na(+) and Cl(-) concentrations to sustain transport, is inhibited noncompetitively by 5-HT, and is more sensitive to SERT inhibitors, including selective serotonin reuptake inhibitors. We use a thiol-reactive methane thiosulfonate (MTS) reagent to modify a conformationally sensitive cysteine residue to demonstrate that hSERT spends more time in an outward facing conformation when transporting DA than when transporting 5-HT. Cotransfection of an inactive or an MTS-sensitive SERT with wild-type SERT subunits reveals an absence of cooperative interactions between subunits during DA but not 5-HT transport. To establish the physiological relevance of this mechanism for DA clearance, we show using in vivo high-speed chronoamperometry that SERT has the capacity to clear extracellularly applied DA in the hippocampal CA3 region of anesthetized rats. Together, these observations suggest the possibility that SERT serves as a DA transporter in vivo and highlight the idea that there can be distinct modes of transport of alternative physiological substrates by SERT.
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Affiliation(s)
- Mads Breum Larsen
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15260
| | - Mark S. Sonders
- Center for Molecular Recognition, Columbia University and New York State Psychiatric Institute, New York, New York 10032, and
| | - Ole Valente Mortensen
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15260
| | - Gaynor A. Larson
- Department of Pharmacology, University of Colorado Denver, Aurora, Colorado 80045
| | - Nancy R. Zahniser
- Department of Pharmacology, University of Colorado Denver, Aurora, Colorado 80045
| | - Susan G. Amara
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15260
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41
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Daws LC, Gould GG. Ontogeny and regulation of the serotonin transporter: providing insights into human disorders. Pharmacol Ther 2011; 131:61-79. [PMID: 21447358 DOI: 10.1016/j.pharmthera.2011.03.013] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Accepted: 03/11/2011] [Indexed: 12/17/2022]
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) was one of the first neurotransmitters for which a role in development was identified. Pharmacological and gene knockout studies have revealed a critical role for 5-HT in numerous processes, including cell division, neuronal migration, differentiation and synaptogenesis. An excess in brain 5-HT appears to be mechanistically linked to abnormal brain development, which in turn is associated with neurological disorders. Ambient levels of 5-HT are controlled by a vast orchestra of proteins, including a multiplicity of pre- and post-synaptic 5-HT receptors, heteroreceptors, enzymes and transporters. The 5-HT transporter (SERT, 5-HTT) is arguably the most powerful regulator of ambient extracellular 5-HT. SERT is the high-affinity uptake mechanism for 5-HT and exerts tight control over the strength and duration of serotonergic neurotransmission. Perturbation of its expression level or function has been implicated in many diseases, prominent among them are psychiatric disorders. This review synthesizes existing information on the ontogeny of SERT during embryonic and early postnatal development though adolescence, along with factors that influence its expression and function during these critical developmental windows. We integrate this knowledge to emphasize how inappropriate SERT expression or its dysregulation may be linked to the pathophysiology of psychiatric, cardiovascular and gastrointestinal diseases.
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Affiliation(s)
- Lynette C Daws
- Department of Physiology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, MC 7756, San Antonio, TX 78229-3900, USA.
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42
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Haenisch B, Bönisch H. Depression and antidepressants: Insights from knockout of dopamine, serotonin or noradrenaline re-uptake transporters. Pharmacol Ther 2011; 129:352-68. [DOI: 10.1016/j.pharmthera.2010.12.002] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Accepted: 11/29/2010] [Indexed: 12/15/2022]
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Navailles S, De Deurwaerdère P. Presynaptic control of serotonin on striatal dopamine function. Psychopharmacology (Berl) 2011; 213:213-42. [PMID: 20953589 DOI: 10.1007/s00213-010-2029-y] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Accepted: 09/14/2010] [Indexed: 11/27/2022]
Abstract
RATIONALE The influences of the serotonergic system on dopamine (DA) neuron activity have received considerable attention during the last three decades due to the real opportunity to improve disorders related to central DA neuron dysfunctions such as Parkinson's disease, schizophrenia, or drug abuse with serotonergic drugs. Numerous biochemical and behavioral data indicate that serotonin (5-HT) affects dopaminergic terminal function in the striatum. OBJECTIVE The authors propose a thorough examination of data showing controversial effects induced by striatal 5-HT on dopaminergic activity. RESULTS Inhibitory and excitatory effects of exogenous 5-HT have been reported on DA release and synthesis, involving various striatal 5-HT receptors. 5-HT also promotes an efflux of DA through reversal of the direction of DA transport. By analogy with the mechanism of action described for amphetamine, the consequences of 5-HT entering DA terminals might explain both the excitatory and inhibitory effects of 5-HT on presynaptic DA terminal activity, but the physiological relevance of this mechanism is far from clear. The recent data suggest that the endogenous 5-HT system affects striatal DA release in a state-dependent manner associated with the conditional involvement of various 5-HT receptors such as 5-HT(2A), 5-HT(2C), 5-HT(3), and 5-HT(4) receptors. CONCLUSION Methodological and pharmacological issues have prevented a comprehensive overview of the influence of 5-HT on striatal DA activity. The distribution of striatal 5-HT receptors and their restricted influence on DA neuron activity suggest that the endogenous 5-HT system exerts multiple and subtle influences on DA-mediated behaviors.
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Affiliation(s)
- Sylvia Navailles
- Unité Mixte de Recherche Centre National de la Recherche Scientifique 5227, Université Victor Segalen Bordeaux 2, Bordeaux, France
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Olivier JDA, Cools AR, Deen PMT, Olivier B, Ellenbroek BA. Blockade of dopamine, but not noradrenaline, transporters produces hyperthermia in rats that lack serotonin transporters. Eur J Pharmacol 2009; 629:7-11. [PMID: 20004658 DOI: 10.1016/j.ejphar.2009.11.049] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2008] [Revised: 11/13/2009] [Accepted: 11/23/2009] [Indexed: 11/24/2022]
Abstract
To investigate whether life-long disturbed serotonin neurotransmission may result in adaptive changes of dopaminergic and noradrenergic systems, effects of drugs on stress-induced hyperthermia were studied in serotonin transporter knockout rats. The noradrenalin transporter blocker atomoxetine was more effective in reducing stress-induced hyperthermia, induced by an injection, in serotonin transporter (SERT) knockout (SERT(-/-)) rats compared to SERT(+/+) rats. The dopamine transporter blocker GBR12909 increased the core body temperature in SERT(-/-) rats, and had no effect on the SERT(+/+) rats. Finally, the noradrenalin transporter together with dopamine transporter blocker bupropion was more effective in decreasing the stress of an injection in SERT(-/-) rats than in SERT(+/+) rats. These data suggest that the sensitivity of dopamine and noradrenalin receptors is changed in serotonin transporter knockout rats. The lack of the serotonin transporter in SERT(-/-) rats might reflect humans with a life-long disturbed serotonin system, making this rat a good model to study possible changes in dopaminergic and noradrenergic systems in psychiatric disorders.
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Affiliation(s)
- Jocelien D A Olivier
- Donders Institute for Brain, Cognition and Behaviour: Department of Cognitive Neuroscience: Molecular Neurobiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
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Baughman KR, Bourguet CC, Ober SK. Gender differences in the association between antidepressant use and restless legs syndrome. Mov Disord 2009; 24:1054-9. [PMID: 19353713 DOI: 10.1002/mds.22517] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Contradictory results have been reported for the association between antidepressant use and Restless Legs Syndrome (RLS). Our aim was to clarify the relationship and examine possible gender differences. We interviewed 1,693 veterans receiving primary care from the Cleveland VA Medical Center and obtained prescription drug information from their medical records. Overall, use of an antidepressant was associated with RLS for men (RR = 1.77, CI = 1.26, 2.48) but not for women (RR = 0.79, CI = 0.43, 1.47). Analyses of individual antidepressants revealed an association between RLS and fluoxetine for women (RR = 2.47, CI = 1.33, 4.56), and associations between RLS and citalopram, (RR = 2.09, CI = 1.20, 3.64), paroxetine (RR = 1.97, CI = 1.02, 3.79), and amitriptyline (RR = 2.40, CI = 1.45, 4.00) for men. We conclude that RLS may be associated with antidepressant use, but the association varies by gender and type of antidepressant. Antidepressant use is more strongly associated with RLS in men than in women.
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Affiliation(s)
- Kristin R Baughman
- Department of Behavioral and Community Health Sciences, Northeastern Ohio Universities Colleges of Medicine and Pharmacy, Rootstown, Ohio 44272, USA.
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Stillman AA, Krsnik Z, Sun J, Rasin MR, State MW, Sestan N, Louvi A. Developmentally regulated and evolutionarily conserved expression of SLITRK1 in brain circuits implicated in Tourette syndrome. J Comp Neurol 2009; 513:21-37. [PMID: 19105198 DOI: 10.1002/cne.21919] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Tourette syndrome (TS) is an inherited developmental neuropsychiatric disorder characterized by vocal and motor tics. Multiple lines of neurophysiological evidence implicate dysfunction in the corticostriatal-thalamocortical circuits in the etiology of TS. We recently identified rare sequence variants in the Slit and Trk-like family member 1 (SLITRK1) gene associated with TS. SLITRK1, a single-pass transmembrane protein, displays similarities to the SLIT family of secreted ligands, which have roles in axonal repulsion and dendritic patterning, but its function and developmental expression remain largely unknown. Here we provide evidence that SLITRK1 has a developmentally regulated expression pattern in projection neurons of the corticostriatal-thalamocortical circuits. SLITRK1 is further enriched in the somatodendritic compartment and cytoplasmic vesicles of cortical pyramidal neurons in mouse, monkey, and human brain, observations suggestive of an evolutionarily conserved function in mammals. SLITRK1 is transiently expressed in the striosomal/patch compartment of the mammalian striatum and moreover is associated with the direct output pathway; adult striatal expression is confined to cholinergic interneurons. These analyses demonstrate that the expression of SLITRK1 is dynamic and specifically associated with the circuits most commonly implicated in TS and related disorders, suggesting that SLITRK1 contributes to the development of corticostriatal-thalamocortical circuits.
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Affiliation(s)
- Althea A Stillman
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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Neurochemical, behavioral, and physiological effects of pharmacologically enhanced serotonin levels in serotonin transporter (SERT)-deficient mice. Psychopharmacology (Berl) 2008; 201:203-18. [PMID: 18712364 PMCID: PMC2584159 DOI: 10.1007/s00213-008-1268-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2008] [Accepted: 07/17/2008] [Indexed: 02/07/2023]
Abstract
RATIONALE Serotonin transporter (SERT) knockout (-/-) mice have an altered phenotype in adulthood, including high baseline anxiety and depressive-like behaviors, associated with increased baseline extracellular serotonin levels throughout life. OBJECTIVES To examine the effects of increases in serotonin following the administration of the serotonin precursor 5-hydroxy-L-tryptophan (5-HTP) in SERT wild-type (+/+), heterozygous (+/-), and -/- mice. RESULTS 5-HTP increased serotonin in all five brain areas examined with approximately 2- to 5-fold increases in SERT+/+ and +/- mice, and with greater 4.5- to 11.7-fold increases in SERT-/- mice. Behaviorally, 5-HTP induced exaggerated serotonin syndrome behaviors in SERT-/-, mice with similar effects in male and female mice. Studies suggest promiscuous serotonin uptake by the dopamine transporter (DAT) in SERT-/- mice, and here, the DAT blocker GBR 12909 enhanced 5-HTP-induced behaviors in SERT-/- mice. Physiologically, 5-HTP induced exaggerated temperature effects in SERT-deficient mice. The 5-HT1A antagonist WAY 100635 decreased 5-HTP-induced hypothermia in SERT+/+ and +/- mice with no effect in SERT-/- mice, whereas the 5-HT7 antagonist SB 269970 decreased this exaggerated response in SERT-/- mice only. WAY 100635 and SB 269970 together completely blocked 5-HTP-induced hypothermia in SERT+/- and -/- mice. CONCLUSIONS These studies demonstrate that SERT-/- mice have exaggerated neurochemical, behavioral, and physiological responses to further increases in serotonin, and provide the first evidence of intact 5-HT7 receptor function in SERT-/- mice, with interesting interactions between 5-HT1A and 5-HT7 receptors. As roles for 5-HT7 receptors in anxiety and depression were recently established, the current findings have implications for understanding the high anxiety and depressive-like phenotype of SERT-deficient mice.
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Organic cation transporter 3: Keeping the brake on extracellular serotonin in serotonin-transporter-deficient mice. Proc Natl Acad Sci U S A 2008; 105:18976-81. [PMID: 19033200 DOI: 10.1073/pnas.0800466105] [Citation(s) in RCA: 131] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Mood disorders cause much suffering and are the single greatest cause of lost productivity worldwide. Although multiple medications, along with behavioral therapies, have proven effective for some individuals, millions of people lack an effective therapeutic option. A common serotonin (5-HT) transporter (5-HTT/SERT, SLC6A4) polymorphism is believed to confer lower 5-HTT expression in vivo and elevates risk for multiple mood disorders including anxiety, alcoholism, and major depression. Importantly, this variant is also associated with reduced responsiveness to selective 5-HT reuptake inhibitor antidepressants. We hypothesized that a reduced antidepressant response in individuals with a constitutive reduction in 5-HTT expression could arise because of the compensatory expression of other genes that inactivate 5-HT in the brain. A functionally upregulated alternate transporter for 5-HT may prevent extracellular 5-HT from rising to levels sufficiently high enough to trigger the adaptive neurochemical events necessary for therapeutic benefit. Here we demonstrate that expression of the organic cation transporter type 3 (OCT3, SLC22A3), which also transports 5-HT, is upregulated in the brains of mice with constitutively reduced 5-HTT expression. Moreover, the OCT blocker decynium-22 diminishes 5-HT clearance and exerts antidepressant-like effects in these mice but not in WT animals. OCT3 may be an important transporter mediating serotonergic signaling when 5-HTT expression or function is compromised.
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Murphy DL, Fox MA, Timpano KR, Moya PR, Ren-Patterson R, Andrews AM, Holmes A, Lesch KP, Wendland JR. How the serotonin story is being rewritten by new gene-based discoveries principally related to SLC6A4, the serotonin transporter gene, which functions to influence all cellular serotonin systems. Neuropharmacology 2008; 55:932-60. [PMID: 18824000 PMCID: PMC2730952 DOI: 10.1016/j.neuropharm.2008.08.034] [Citation(s) in RCA: 167] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2008] [Revised: 08/15/2008] [Accepted: 08/15/2008] [Indexed: 12/19/2022]
Abstract
Discovered and crystallized over sixty years ago, serotonin's important functions in the brain and body were identified over the ensuing years by neurochemical, physiological and pharmacological investigations. This 2008 M. Rapport Memorial Serotonin Review focuses on some of the most recent discoveries involving serotonin that are based on genetic methodologies. These include examples of the consequences that result from direct serotonergic gene manipulation (gene deletion or overexpression) in mice and other species; an evaluation of some phenotypes related to functional human serotonergic gene variants, particularly in SLC6A4, the serotonin transporter gene; and finally, a consideration of the pharmacogenomics of serotonergic drugs with respect to both their therapeutic actions and side effects. The serotonin transporter (SERT) has been the most comprehensively studied of the serotonin system molecular components, and will be the primary focus of this review. We provide in-depth examples of gene-based discoveries primarily related to SLC6A4 that have clarified serotonin's many important homeostatic functions in humans, non-human primates, mice and other species.
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Affiliation(s)
- Dennis L Murphy
- Laboratory of Clinical Science, NIMH Intramural Research Program, NIH, Building 10, Room 3D41, 10 Center Drive, MSC 1264, Bethesda, MD 20892, USA.
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50
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Unfaithful neurotransmitter transporters: focus on serotonin uptake and implications for antidepressant efficacy. Pharmacol Ther 2008; 121:89-99. [PMID: 19022290 DOI: 10.1016/j.pharmthera.2008.10.004] [Citation(s) in RCA: 160] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2008] [Accepted: 10/14/2008] [Indexed: 01/11/2023]
Abstract
Biogenic amine transporters for serotonin, norepinephrine and dopamine (SERT, NET and DAT respectively), are the key players terminating transmission of these amines in the central nervous system by their high-affinity uptake. They are also major targets for many antidepressant drugs. Interestingly however, drugs targeted to a specific transporter do not appear to be as clinically efficacious as those that block two or all three of these transporters. A growing body of literature, reviewed here, supports the idea that promiscuity among these transporters (the uptake of multiple amines in addition to their "native" transmitter) may account for improved therapeutic effects of dual and triple uptake blockers. However, even these drugs do not provide effective treatment outcomes for all individuals. An emerging literature suggests that "non-traditional" transporters such as organic cation transporters (OCT) and the plasma membrane monoamine transporter (PMAT) may contribute to the less than hoped for efficacy of currently prescribed uptake inhibitors. OCT and PMAT are capable of clearing biogenic amines from extracellular fluid and may serve to buffer the effects of frontline antidepressants, such as selective serotonin reuptake inhibitors. In addition, polymorphisms that occur in the genes encoding the transporters can lead to variation in transporter expression and function (e.g. the serotonin transporter linked polymorphic region; 5-HTTLPR) and can have profound effects on treatment outcome. This may be accounted for, in part, by compensatory adaptations in other transporters. This review synthesizes the existing literature, focusing on serotonin to illustrate and revive a model for the rationale design of improved antidepressants.
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