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Scheggi S, Concas L, Corsi S, Carta M, Melis M, Frau R. Expanding the therapeutic potential of neuro(active)steroids: a promising strategy for hyperdopaminergic behavioral phenotypes. Neurosci Biobehav Rev 2024; 164:105842. [PMID: 39103066 DOI: 10.1016/j.neubiorev.2024.105842] [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: 05/23/2024] [Revised: 07/10/2024] [Accepted: 08/01/2024] [Indexed: 08/07/2024]
Abstract
Imbalances in dopamine activity significantly contribute to the pathophysiology of several neuropsychiatric disorders, including addiction, ADHD, schizophrenia, impulse control disorders, and Parkinson's Disease. Neuro(active)steroids, comprising endogenous steroids that finely modulate neuronal activity, are considered crucial regulators of brain function and behavior, with implications in various physiological processes and pathological conditions. Specifically, subclasses of Neuro(active)steroids belonging to the 5α reductase pathway are prominently involved in brain disorders characterized by dopaminergic signaling imbalances. This review highlights the neuromodulatory effects of Neuro(active)steroids on the dopamine system and related aberrant behavioral phenotypes. We critically appraise the role of pregnenolone, progesterone, and allopregnanolone on dopamine signaling. Additionally, we discuss the impact of pharmacological interventions targeting 5α reductase activity in neuropsychiatric conditions characterized by excessive activation of the dopaminergic system, ranging from psychotic (endo)phenotypes and motor complications to decision-making problems and addiction.
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Affiliation(s)
- Simona Scheggi
- Dept. of Molecular and Developmental Medicine, University of Siena, Italy
| | - Luca Concas
- Dept. Of Biomedical Sciences, University of Cagliari, Italy
| | - Sara Corsi
- Dept. of Developmental and Regenerative Neurobiology, Lund University, Sweden
| | - Manolo Carta
- Dept. Of Biomedical Sciences, University of Cagliari, Italy
| | - Miriam Melis
- Dept. Of Biomedical Sciences, University of Cagliari, Italy
| | - Roberto Frau
- Dept. Of Biomedical Sciences, University of Cagliari, Italy; Guy Everett Laboratory, University of Cagliari, Cagliari, Italy.
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Li D, Hu Y, Liu X, Yu G. Network pharmacology analysis and experimental validation of Anemarrhenae Rhizoma in treating Alzheimer 's disease. Zhejiang Da Xue Xue Bao Yi Xue Ban 2023; 53:84-97. [PMID: 38105702 PMCID: PMC10945494 DOI: 10.3724/zdxbyxb-2023-0362] [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: 08/03/2023] [Accepted: 09/17/2023] [Indexed: 12/19/2023]
Abstract
OBJECTIVES To explore the mechanism of Anemarrhenae Rhizoma in treatment of Alzheimer's Disease (AD). METHODS The active ingredients and targets of Anemarrhenae Rhizoma for treatment of AD were screened with network pharmacology methods, the protein-protein interaction (PPI) network was constructed and the core targets were analyzed. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways enriching analysis was performed. The peripheral blood lymphocytes were extracted and lymphoblastoid cell lines (LCL) were constructed and an in vitro cell model of LCL-SKNMC was established. MTT and CCK-8 methods were used to quantify SKNMC/LCL cells, 2 ´, 7 ´-dichlorodihydrofluorescein diacetate (DCFH-DA) probe was used to detect reactive oxygen species (ROS), and immunofluorescence staining was used to detect the generation of Aβ1-42 in a co-cultured model. Western blotting was used to detect protein expression in the co-culture model. The lifespan of N2 nematodes was observed under oxidative stress, normal state, and heat stress; ROS generated by N2 nematodes was detected by DCFH-DA probes. The paralysis time of CL4176 N2 nematodes was evaluated by paralysis assay, and Aβ deposition in the pharynx was detected by Thioflavin S staining. RESULTS Through network pharmacology, 15 potential active ingredients and 103 drug-disease targets were identified. PPI analysis showed that the Anemarrhenae Rhizoma might play anti-AD roles through albumin, Akt1, tumor necrosis factor, epidermal growth factor receptor (EGFR), vascular endothelial growth factor A (VEGFA), mammalian target of rapamycin (mTOR), amyloid precursor protein (APP) and other related targets. KEGG analysis showed that the pharmacological effects of Anemarrhenae Rhizoma might involve the biological processes of Alzheimer's disease, endocrine resistance, insulin resistance; and neuroactive ligand-receptor interaction, phosphatidylinositol 3-kinase (PI3K)-Akt signaling pathway, calcium signaling pathway, AGE-RAGE signaling pathway in diabetes complications, neurotrophic factor signaling pathway and others. The in vitro cell experiments showed that Anemarrhenae Rhizoma was able to reduce the production of ROS and Aβ1-42 (both P<0.01), inhibit the expression of β-secretase 1 (BACE1), APP and Aβ1-42 proteins (all P<0.05), up-regulate the expression of p-PI3K/PI3K, p-AKT/AKT, p-GSK3β/GSK3β in SKNMC cells (all P<0.05). The in vivo studies further confirmed that Anemarrhenae Rhizoma prolonged the lifespan of C. elegans under stress and normal conditions, reduced the accumulation of ROS and the toxicity of Aβ deposition. CONCLUSIONS Anemarrhenae Rhizoma may reduce the production of Aβ in AD and inhibit its induced oxidative stress, which may be achieved by regulating the PI3K/Akt/GSK-3β pathway.
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Affiliation(s)
- Deyu Li
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China.
| | - Yingchao Hu
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China
| | - Xin Liu
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China
| | - Guran Yu
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China.
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Tapia MA, Sage AS, Fullerton EI, Judd JM, Hildebrant PC, Will MJ, Lever SZ, Lever JR, Miller DK. The sigma receptor ligand N-phenylpropyl-N'-(4-methoxyphenethyl)3piperazine (YZ-067) enhances the cocaine conditioned-rewarding properties while inhibiting the development of sensitization of cocaine in mice. Psychopharmacology (Berl) 2020; 237:723-734. [PMID: 31822924 DOI: 10.1007/s00213-019-05411-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 11/18/2019] [Indexed: 11/28/2022]
Abstract
RATIONALE The N-phenylpropyl-N'-substituted piperazines SA-4503 (N-phenylpropyl-N'-(3,4-dimethoxyphenethyl)piperazine) and YZ-185 (N-phenylpropyl-N'-(3-methoxyphenethyl)piperazine) bind to sigma (σ) receptors and block the development of cocaine-induced conditioned place preference at concentrations that inhibit cocaine-induced hyperactivity. YZ-067 (N-phenylpropyl-N'-(4-methoxyphenethyl)piperazine) also binds to sigma receptors and attenuates cocaine-induced hyperactivity in mice. OBJECTIVES The present study determined the effect of YZ-067 on the development and expression of cocaine (66 μmol/kg or 33 μmol/kg) conditioned place preference (CPP) and locomotor sensitization in mice. RESULTS YZ-067 (10 or 31.6 μmol/kg) did not have intrinsic effects on place preference or place aversion. Interestingly, the 31.6 μmol/kg YZ-067 dose enhanced the development of cocaine place preference, while 10 μmol/kg YZ-067 attenuated the development of cocaine-induced locomotor sensitization. However, YZ-067 did not alter the expression of cocaine place preference nor cocaine-induced locomotor sensitization. In follow-up studies, YZ-067 did not affect performance in the zero maze or rotarod, indicating that sigma receptors probed by this ligand do not regulate anxiety-like or coordinated motor skill behaviors, respectively. CONCLUSION Overall, these results are consistent with previous studies demonstrating a role for sigma receptors in the behavioral effects of cocaine. However, the present findings also indicate that N-phenylpropyl-N'-substituted piperazines do not strictly block cocaine's behavioral effects and that sigma receptor may differentially mediate cocaine-induced hyperactivity and place conditioning.
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Affiliation(s)
- Melissa A Tapia
- Department of Psychological Sciences, University of Missouri, Columbia, MO, 65211, USA.
| | - Andrew S Sage
- Department of Psychological Sciences, University of Missouri, Columbia, MO, 65211, USA
| | - Emma I Fullerton
- Department of Psychological Sciences, University of Missouri, Columbia, MO, 65211, USA
| | - Jessica M Judd
- Department of Psychological Sciences, University of Missouri, Columbia, MO, 65211, USA
| | - Paige C Hildebrant
- Department of Psychological Sciences, University of Missouri, Columbia, MO, 65211, USA
| | - Matthew J Will
- Department of Psychological Sciences, University of Missouri, Columbia, MO, 65211, USA
| | - Susan Z Lever
- Department of Chemistry, University of Missouri, Columbia, MO, 65211, USA.,Research Reactor Center, University of Missouri, Columbia, MO, 65212, USA
| | - John R Lever
- Research Service, Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, 65211, USA.,Departments of Radiology, and Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, 65211, USA
| | - Dennis K Miller
- Department of Psychological Sciences, University of Missouri, Columbia, MO, 65211, USA
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Fanni S, Scheggi S, Rossi F, Tronci E, Traccis F, Stancampiano R, De Montis MG, Devoto P, Gambarana C, Bortolato M, Frau R, Carta M. 5alpha-reductase inhibitors dampen L-DOPA-induced dyskinesia via normalization of dopamine D1-receptor signaling pathway and D1-D3 receptor interaction. Neurobiol Dis 2018; 121:120-130. [PMID: 30261284 DOI: 10.1016/j.nbd.2018.09.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 09/06/2018] [Accepted: 09/18/2018] [Indexed: 12/20/2022] Open
Abstract
Although 1-3,4-dihydroxyphenylalanine (L-DOPA) is the mainstay therapy for treating Parkinson's disease (PD), its long-term administration is accompanied by the development of motor complications, particularly L-DOPA induced dyskinesia (LID), that dramatically affects patients' quality of life. LID has consistently been related to an excessive dopamine receptor transmission, particularly at the down-stream signaling of the striatal D1 receptors (D1R), resulting in an exaggerated stimulation of cAMP-dependent protein kinase and extracellular signal-regulated kinase (ERK) pathway. We previously reported that pharmacological blockade of 5alpha-reductase (5AR), the rate-limiting enzyme in neurosteroids synthesis, attenuates the severity of a broad set of behavioral alterations induced by D1R and D3R activation, without inducing extrapyramidal symptoms. In line with this evidence, in a recent study, we found that inhibition of 5AR by finasteride (FIN) produced a significant reduction of dyskinesia induced by L-DOPA and direct dopaminergic agonists in 6-OHDA-lesioned rats. In the attempt to further investigate the effect of 5AR inhibitors on dyskinesia and shed light on the mechanism of action, in the present study we compared the effect of FIN and dutasteride (DUTA), a potent dual 5AR inhibitor, on the development of LID, on the therapeutic efficacy of L-DOPA, on the molecular alterations downstream to the D1R, as well as on D1R-D3R interaction. The results indicated that both FIN and DUTA administration significantly reduced development and expression of LID; however, DUTA appeared more effective than FIN at a lower dose and produced its antidyskinetic effect without impacting the ability of L-DOPA to increase motor activation, or ameliorate forelimb use in parkinsonian rats. Moreover, this study demonstrates for the first time that 5AR inhibitors are able to prevent key events in the appearance of dyskinesia, such as L-DOPA-induced upregulation of striatal D1R-related cAMP/PKA/ERK signaling pathways and D1R-D3R coimmunoprecipitation, an index of heteromer formation. These findings are relevant as they confirm the 5AR enzyme as a potential therapeutic target for treatment of dyskinesia in PD, suggesting the first ever evidence that neurosteroidogenesis may affect functional interaction between dopamine D1R and D3R.
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Affiliation(s)
- Silvia Fanni
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria SP 8, Monserrato 09042, Italy
| | - Simona Scheggi
- Department of Molecular and Developmental Medicine, University of Siena, Via Aldo Moro 4, 53100 Siena, Italy
| | - Francesca Rossi
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria SP 8, Monserrato 09042, Italy
| | - Elisabetta Tronci
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria SP 8, Monserrato 09042, Italy
| | - Francesco Traccis
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria SP 8, Monserrato 09042, Italy
| | - Roberto Stancampiano
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria SP 8, Monserrato 09042, Italy
| | - Maria Graziella De Montis
- Department of Molecular and Developmental Medicine, University of Siena, Via Aldo Moro 4, 53100 Siena, Italy
| | - Paola Devoto
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria SP 8, Monserrato 09042, Italy
| | - Carla Gambarana
- Department of Molecular and Developmental Medicine, University of Siena, Via Aldo Moro 4, 53100 Siena, Italy
| | - Marco Bortolato
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, 30 S 2000 E, Salt Lake City, UT 84112, USA
| | - Roberto Frau
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria SP 8, Monserrato 09042, Italy; Tourette Syndrome Center, University of Cagliari, Cittadella Universitaria SP 8, Monserrato 09042, Italy; Sleep Medicine Center, University of Cagliari, Cittadella Universitaria SP 8, Monserrato 09042, Italy; National Institute of Neuroscience (INN), University of Cagliari, Monserrato, CA, Italy.
| | - Manolo Carta
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria SP 8, Monserrato 09042, Italy.
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García-Pardo MP, De la Rubia Ortí JE, Aguilar Calpe MA. Differential effects of MDMA and cocaine on inhibitory avoidance and object recognition tests in rodents. Neurobiol Learn Mem 2017; 146:1-11. [PMID: 29081371 DOI: 10.1016/j.nlm.2017.10.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 10/23/2017] [Accepted: 10/24/2017] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Drug addiction continues being a major public problem faced by modern societies with different social, health and legal consequences for the consumers. Consumption of psychostimulants, like cocaine or MDMA (known as ecstasy) are highly prevalent and cognitive and memory impairments have been related with the abuse of these drugs. AIM The aim of this work was to review the most important data of the literature in the last 10 years about the effects of cocaine and MDMA on inhibitory avoidance and object recognition tests in rodents. DEVELOPMENT The object recognition and the inhibitory avoidance tests are popular procedures used to assess different types of memory. We compare the effects of cocaine and MDMA administration in these tests, taking in consideration different factors such as the period of life development of the animals (prenatal, adolescence and adult age), the presence of polydrug consumption or the role of environmental variables. Brain structures involved in the effects of cocaine and MDMA on memory are also described. CONCLUSIONS Cocaine and MDMA induced similar impairing effects on the object recognition test during critical periods of lifetime or after abstinence of prolonged consumption in adulthood. Deficits of inhibitory avoidance memory are observed only in adult rodents exposed to MDMA. Psychostimulant abuse is a potential factor to induce memory impairments and could facilitate the development of future neurodegenerative disorders.
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Meyer MAA, Corcoran KA, Chen HJ, Gallego S, Li G, Tiruveedhula VV, Cook JM, Radulovic J. Neurobiological correlates of state-dependent context fear. ACTA ACUST UNITED AC 2017; 24:385-391. [PMID: 28814463 PMCID: PMC5580530 DOI: 10.1101/lm.045542.117] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 06/07/2017] [Indexed: 12/02/2022]
Abstract
Retrieval of fear memories can be state-dependent, meaning that they are best retrieved if the brain states at encoding and retrieval are similar. Such states can be induced by activating extrasynaptic γ-aminobutyric acid type A receptors (GABAAR) with the broad α-subunit activator gaboxadol. However, the circuit mechanisms and specific subunits underlying gaboxadol's effects are not well understood. Here we show that gaboxadol induces profound changes of local and network oscillatory activity, indicative of discoordinated hippocampal–cortical activity, that were accompanied by robust and long-lasting state-dependent conditioned fear. Episodic memories typically are hippocampus-dependent for a limited period after learning, but become cortex-dependent with the passage of time. In contrast, state-dependent memories continued to rely on hippocampal GABAergic mechanisms for memory retrieval. Pharmacological approaches with α-subunit-specific agonists targeting the hippocampus implicated the prototypic extrasynaptic subunits (α4) as the mediator of state-dependent conditioned fear. Together, our findings suggest that continued dependence on hippocampal rather than cortical mechanisms could be an important feature of state-dependent memories that contributes to their conditional retrieval.
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Affiliation(s)
- Mariah A A Meyer
- Department of Psychiatry and Behavioral Sciences, Northwestern University, Chicago, Illinois 60611, USA
| | - Kevin A Corcoran
- Department of Psychiatry and Behavioral Sciences, Northwestern University, Chicago, Illinois 60611, USA
| | - Helen J Chen
- Department of Psychiatry and Behavioral Sciences, Northwestern University, Chicago, Illinois 60611, USA
| | - Sonia Gallego
- Department of Psychiatry and Behavioral Sciences, Northwestern University, Chicago, Illinois 60611, USA
| | - Guanguan Li
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, USA
| | - Veda V Tiruveedhula
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, USA
| | - James M Cook
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, USA
| | - Jelena Radulovic
- Department of Psychiatry and Behavioral Sciences, Northwestern University, Chicago, Illinois 60611, USA
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Radulovic J, Jovasevic V, Meyer MA. Neurobiological mechanisms of state-dependent learning. Curr Opin Neurobiol 2017; 45:92-98. [PMID: 28558266 DOI: 10.1016/j.conb.2017.05.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Accepted: 05/14/2017] [Indexed: 01/06/2023]
Abstract
State-dependent learning (SDL) is a phenomenon relating to information storage and retrieval restricted to discrete states. While extensively studied using psychopharmacological approaches, SDL has not been subjected to rigorous neuroscientific study. Here we present an overview of approaches historically used to induce SDL, and highlight some of the known neurobiological mechanisms, in particular those related to inhibitory neurotransmission and its regulation by microRNAs (miR). We also propose novel cellular and circuit mechanisms as contributing factors. Lastly, we discuss the implications of advancing our knowledge on SDL, both for most fundamental processes of learning and memory as well as for development and maintenance of psychopathology.
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Affiliation(s)
- Jelena Radulovic
- Department of Psychiatry and Behavioral Sciences, The Asher Center for Study and Treatment of Depressive Disorders, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.
| | - Vladimir Jovasevic
- Department of Psychiatry and Behavioral Sciences, The Asher Center for Study and Treatment of Depressive Disorders, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Mariah Aa Meyer
- Department of Psychiatry and Behavioral Sciences, The Asher Center for Study and Treatment of Depressive Disorders, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
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The spinal antinociceptive mechanism determined by systemic administration of BD1047 in zymosan-induced hyperalgesia in rats. Brain Res Bull 2015; 119:93-100. [DOI: 10.1016/j.brainresbull.2015.07.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 07/22/2015] [Accepted: 07/24/2015] [Indexed: 02/07/2023]
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Abstract
This review compares the biological and physiological function of Sigma receptors [σRs] and their potential therapeutic roles. Sigma receptors are widespread in the central nervous system and across multiple peripheral tissues. σRs consist of sigma receptor one (σ1R) and sigma receptor two (σ2R) and are expressed in numerous regions of the brain. The sigma receptor was originally proposed as a subtype of opioid receptors and was suggested to contribute to the delusions and psychoses induced by benzomorphans such as SKF-10047 and pentazocine. Later studies confirmed that σRs are non-opioid receptors (not an µ opioid receptor) and play a more diverse role in intracellular signaling, apoptosis and metabolic regulation. σ1Rs are intracellular receptors acting as chaperone proteins that modulate Ca2+ signaling through the IP3 receptor. They dynamically translocate inside cells, hence are transmembrane proteins. The σ1R receptor, at the mitochondrial-associated endoplasmic reticulum membrane, is responsible for mitochondrial metabolic regulation and promotes mitochondrial energy depletion and apoptosis. Studies have demonstrated that they play a role as a modulator of ion channels (K+ channels; N-methyl-d-aspartate receptors [NMDAR]; inositol 1,3,5 triphosphate receptors) and regulate lipid transport and metabolism, neuritogenesis, cellular differentiation and myelination in the brain. σ1R modulation of Ca2+ release, modulation of cardiac myocyte contractility and may have links to G-proteins. It has been proposed that σ1Rs are intracellular signal transduction amplifiers. This review of the literature examines the mechanism of action of the σRs, their interaction with neurotransmitters, pharmacology, location and adverse effects mediated through them.
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Affiliation(s)
- Colin G Rousseaux
- a Department of Pathology and Laboratory Medicine , University of Ottawa , Ottawa , ON , Canada and
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Gill KE, Rice BA, Akins CK. Cocaine induces state-dependent learning of sexual conditioning in male Japanese quail. Physiol Behav 2015; 138:150-3. [PMID: 25447336 PMCID: PMC4263280 DOI: 10.1016/j.physbeh.2014.10.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Revised: 10/01/2014] [Accepted: 10/22/2014] [Indexed: 11/16/2022]
Abstract
State dependent learning effects have been widely studied in a variety of drugs of abuse. However, they have yet to be studied in relation to sexual motivation. The current study investigated state-dependent learning effects of cocaine in male Japanese quail (Coturnix japonica) using a sexual conditioning paradigm. Cocaine-induced state-dependent learning effects were investigated using a 2×2 factorial design with training state as one factor and test state as the other factor. During a 14-day training phase, male quail were injected once daily with 10mg/kg cocaine or saline and then placed in a test chamber after 15min. In the test chamber, sexual conditioning trials consisted of presentation of a light conditioned stimulus (CS) followed by sexual reinforcement. During the state dependent test, half of the birds received a shift in drug state from training to testing (Coc→Sal or Sal→Coc) while the other half remained in the same drug state (Coc→Coc or Sal→Sal). Results showed that male quail that were trained and tested in the same state (Coc→Coc or Sal→Sal) showed greater sexual conditioning than male quail that were trained and tested in different states (Sal→Coc) except when cocaine was administered chronically prior to the test (Coc→Sal). For the latter condition, sexual conditioning persisted from cocaine training to the saline test. The findings suggest that state dependent effects may alter sexual motivation and that repeated exposure to cocaine during sexual activity may increase sexual motivation which, in turn, may lead to high risk sexual activities. An alternative explanation for the findings is also discussed.
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Affiliation(s)
- Karin E Gill
- Department of Psychology, University of Kentucky, Lexington, KY 40506, United States
| | - Beth Ann Rice
- Department of Psychology, University of Kentucky, Lexington, KY 40506, United States
| | - Chana K Akins
- Department of Psychology, University of Kentucky, Lexington, KY 40506, United States.
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Effects of inhibitory GABA-active neurosteroids on cocaine seeking and cocaine taking in rats. Psychopharmacology (Berl) 2014; 231:3391-400. [PMID: 24398823 DOI: 10.1007/s00213-013-3404-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 12/03/2013] [Indexed: 10/25/2022]
Abstract
RATIONALE Several compounds that potentiate GABA-induced inhibitory currents also decrease stress, anxiety and addiction-related behaviors. Because of the well-established connection between stress and addiction, compounds that reduce stress-induced responses might be efficacious in treating addiction. Since endogenous neurosteroids such as allopregnanolone may function in a manner similar to benzodiazepines to reduce HPA axis activation and anxiety following stressful stimuli, we hypothesized that exogenously applied neurosteroids would reduce cocaine reinforcement in two animal models. METHODS Male Wistar rats were trained to self-administer cocaine and food under a concurrent alternating operant schedule of reinforcement. Two separate groups of rats were trained to self-administer cocaine or food pellets and were then exposed to similar cue-induced reinstatement paradigms. Both groups of rats were pretreated with various doses of neurosteroids. RESULTS Allopregnanolone and 3α-hydroxy-3β-methyl-17β-nitro-5α-androstane (R6305-7, a synthetic neurosteroid) were ineffective in selectively decreasing cocaine relative to food self-administration. On the other hand, both allopregnanolone and R6305-7 significantly decreased the cue-induced reinstatement of extinguished cocaine seeking, confirmed by one-way ANOVA. CONCLUSIONS These results suggest that neurosteroids may be effective in reducing the relapse to cocaine use without affecting ongoing cocaine self-administration.
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Role of GABA-active neurosteroids in the efficacy of metyrapone against cocaine addiction. Behav Brain Res 2014; 271:269-76. [PMID: 24959859 DOI: 10.1016/j.bbr.2014.06.032] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 06/09/2014] [Accepted: 06/16/2014] [Indexed: 01/29/2023]
Abstract
Previous research has demonstrated a complicated role for stress and HPA axis activation in potentiating various cocaine-related behaviors in preclinical models of drug dependence. However, the investigation of several antiglucocorticoid therapies has yielded equivocal results in reducing cocaine-related behaviors, possibly because of varying mechanisms of actions. Specifically, research suggests that metyrapone (a corticosterone synthesis inhibitor) may reduce cocaine self-administration in rats via a nongenomic, extra-adrenal mechanism without altering plasma corticosterone. In the current experiments, male rats were trained to self-administer cocaine infusions and food pellets in a multiple, alternating schedule of reinforcement. Metyrapone pretreatment dose-dependently decreased cocaine self-administration as demonstrated previously. Pharmacological inhibition of neurosteroid production by finasteride had significant effects on cocaine self-administration, regardless of metyrapone pretreatment. However, metyrapone's effects on cocaine self-administration were significantly attenuated with bicuculline pretreatment, suggesting a role for GABA-active neurosteroids in cocaine-reinforced behaviors. In vitro binding data also confirmed that metyrapone does not selectively bind to GABA-related proteins. The results of these experiments support the hypothesis that metyrapone may increase neurosteroidogenesis to produce effects on cocaine-related behaviors.
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Roh DH, Yoon SY. Sigma-1 receptor antagonist, BD1047 reduces nociceptive responses and phosphorylation of p38 MAPK in mice orofacial formalin model. Biol Pharm Bull 2013; 37:145-51. [PMID: 24152609 DOI: 10.1248/bpb.b13-00690] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
Sigma-1 receptors (Sig-1Rs) play a role in different types of pain and in central sensitization mechanism in spinal cord. However, it is currently unexplored whether Sig-1Rs are involved in orofacial pain processing. Here we show whether a selective Sig-1R antagonist, BD1047 reduces nociceptive responses in the mouse orofacial formalin model and the number of Fos-immunoreactive (ir) cells in the trigeminal nucleus caudalis (TNC). In addition, it was examined whether the phosphorylation of extracellular signal-regulated kinase (pERK) or p38 (pp38) mitogen-activated protein kinases (MAPK), which are closely linked to pain signaling and sensitization, in TNC was modified by BD1047. The 5% formalin (10 µL) was subcutaneously injected into the right upper lip, and the rubbing responses with ipsilateral fore- or hind paw were counted for 45 min. BD1047 (1, 3 or 10 mg/kg) were intraperitoneally treated 30 min before formalin injection. High dose of BD1047 (10 mg/kg) produced significant anti-nociceptive effects in the first and the second phase. The number of Fos-ir cells in ipsilateral side of TNC was also reduced by BD1047 as compared to that in saline-treated animals. In addition, the number of pp38-ir cells in ipsilateral TNC was decreased in BD1047-treated animals, whereas the number of pERK-ir cells was not modified. Collectively, these results demonstrate that Sig-1Rs play a pivotal role in the orofacial pain processing, and the pp38 signaling pathway can be associated with Sig-1R's action in TNC.
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Affiliation(s)
- Dae-Hyun Roh
- Department of Maxillofacial Tissue Regeneration and Research Center for Tooth and Periodontal Tissue Regeneration, School of Dentistry, Kyung Hee University
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N-Phenylpropyl-N'-(3-methoxyphenethyl)piperazine (YZ-185) Attenuates the Conditioned-Rewarding Properties of Cocaine in Mice. ISRN PHARMACOLOGY 2013; 2013:546314. [PMID: 24089641 PMCID: PMC3780704 DOI: 10.1155/2013/546314] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 08/07/2013] [Indexed: 11/17/2022]
Abstract
Sigma receptor antagonists diminish the effects of cocaine in behavioral assays, including conditioned place preference. Previous locomotor activity experiments in mice determined that the sigma receptor ligand YZ-185 (N-phenylpropyl-N′-(3-methoxyphenethyl)piperazine) enhanced cocaine-induced hyperactivity at a lower (0.1 μmol/kg) dose and dose-dependently attenuated cocaine-induced hyperactivity at higher (3.16–31.6 μmol/kg) doses. The present study investigated the effect of YZ-185 on cocaine's conditioned-rewarding properties in mice. YZ-185 (0.1, 0.316, 3.16, and 31.6 μmol/kg) did not have intrinsic activity to produce conditioned place preference or aversion. A higher (31.6 μmol/kg) YZ-185 dose, but not lower (0.1–3.16 μmol/kg) YZ-185 doses, prevented the development of place preference to cocaine (66 μmol/kg). YZ-185 did not alter the expression of cocaine place preference. To further characterize YZ-185's behavioral profile, its effects in the elevated zero maze and rotarod procedures were also determined; YZ-185 produced no significant change from baseline in either assay, indicating that the sigma receptors probed by YZ-185 do not regulate anxiety-like or coordinated motor skill behaviors. Overall, these results suggest that YZ-185 is a sigma receptor antagonist at the 31.6 μmol/kg dose and demonstrate that sigma receptors can mediate the development of the conditioned-rewarding properties of cocaine.
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González-Usano A, Cauli O, Agustí A, Felipo V. Hyperammonemia alters the modulation by different neurosteroids of the glutamate-nitric oxide-cyclic GMP pathway through NMDA- GABAA - or sigma receptors in cerebellum in vivo. J Neurochem 2013; 125:133-43. [PMID: 23227932 DOI: 10.1111/jnc.12119] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 12/03/2012] [Accepted: 12/04/2012] [Indexed: 01/21/2023]
Abstract
Several neurosteroids modulate the glutamate-nitric oxide (NO)-cGMP pathway in cerebellum through modulation of NMDA- GABAA - or sigma receptors. Hyperammonemia alters the concentration of several neurosteroids and impairs the glutamate-NO-cGMP pathway, leading to impaired learning ability. This work aimed to assess whether chronic hyperammonemia alters the modulation by different neurosteroids of GABAA, NMDA, and/or sigma receptors and of the glutamate-NO-cGMP pathway in cerebellum. Neurosteroids were administered through microdialysis probes, and extracellular cGMP and citrulline were measured. Then NMDA was administered to assess the effects on the glutamate-NO-cGMP pathway activation. Hyperammonemia completely modifies the effects of pregnanolone and pregnenolone. Pregnanolone acts as a GABAA receptor agonist in controls, but as an NMDA receptor antagonist in hyperammonemic rats. Pregnenolone does not induce any effect in controls, but acts as a sigma receptor agonist in hyperammonemic rats. Hyperammonemia potentiates the actions of tetrahydrodeoxy-corticosterone (THDOC) as a GABAA receptor agonist, allopregnanolone as an NMDA receptor antagonist, and pregnenolone sulfate as an NMDA receptor activation enhancer. Neurosteroids that reduce the pathway (pregnanolone, THDOC, allopregnanolone, DHEAS) may contribute to cognitive impairment in hyperammonemia and hepatic encephalopathy. Pregnenolone would impair cognitive function in hyperammonemia. Neurosteroids that restore the pathway in hyperammonemia (pregnenolone sulfate) could restore cognitive function in hyperammonemia and encephalopathy.
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Affiliation(s)
- Alba González-Usano
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
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16
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Smith KJ, Butler TR, Prendergast MA. Inhibition of sigma-1 receptor reduces N-methyl-D-aspartate induced neuronal injury in methamphetamine-exposed and -naive hippocampi. Neurosci Lett 2010; 481:144-8. [PMID: 20600592 PMCID: PMC2923551 DOI: 10.1016/j.neulet.2010.06.069] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2010] [Revised: 06/23/2010] [Accepted: 06/23/2010] [Indexed: 12/17/2022]
Abstract
Acute and prolonged methamphetamine (METH) exposure has been reported to moderate the function of N-methyl-d-aspartate type glutamate receptors (NMDAr) in the hippocampus. These effects have been found to be associated with enhanced NMDAr-dependent release of Ca(2+) from IP(3)-sensitive intracellular stores. The present studies were designed to extend these findings and examine the role of the endoplasmic membrane (ER) bound orphan receptor, the sigma-1 receptor, in NMDA-induced neuronal injury and METH withdrawal-potentiated NMDA-induced neuronal injury. Organotypic hippocampal slice cultures were exposed to METH (0 or 100microM) for 6 days and withdrawn for 7 days, then exposed to NMDA (0 or 5microM) for 24h. Additional cultures were also exposed to this regimen and were co-incubated with BD1047 (100microM), a specific inhibitor of ER-bound sigma-1 receptors, for the 24h NMDA exposure. Cytotoxicity was assessed by analysis of propidium iodide uptake. These studies demonstrated that protracted METH exposure and withdrawal significantly potentiated the neuronal injury produced by NMDA exposure. Further, co-exposure to BD1047 with NMDA markedly attenuated neuronal injury in METH-naïve and METH-withdrawn organotypic cultures. As a whole, these data demonstrate that prolonged METH exposure, even at non-toxic concentrations, significantly alters glutamate receptor signaling. Inhibition of sigma-1 receptor-dependent Ca(2+) release from the ER entirely prevented NMDA-induced toxicity in METH-naïve cultures and markedly reduced METH-potentiated toxicity. These findings demonstrate the importance of Ca(2+)-induced intracellular Ca(2+) release in excitotoxic insult and suggest that blockade of glutamatergic overactivity may represent a therapeutic target in the treatment of METH withdrawal.
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Affiliation(s)
- Katherine J Smith
- Department of Psychology, Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536-0356, USA.
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Cobos EJ, Entrena JM, Nieto FR, Cendán CM, Del Pozo E. Pharmacology and therapeutic potential of sigma(1) receptor ligands. Curr Neuropharmacol 2010; 6:344-66. [PMID: 19587856 PMCID: PMC2701284 DOI: 10.2174/157015908787386113] [Citation(s) in RCA: 295] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2007] [Revised: 07/18/2008] [Accepted: 07/09/2008] [Indexed: 11/22/2022] Open
Abstract
Sigma (σ) receptors, initially described as a subtype of opioid receptors, are now considered unique receptors. Pharmacological studies have distinguished two types of σ receptors, termed σ1 and σ2. Of these two subtypes, the σ1 receptor has been cloned in humans and rodents, and its amino acid sequence shows no homology with other mammalian proteins. Several psychoactive drugs show high to moderate affinity for σ1 receptors, including the antipsychotic haloperidol, the antidepressant drugs fluvoxamine and sertraline, and the psychostimulants cocaine and methamphetamine; in addition, the anticonvulsant drug phenytoin allosterically modulates σ1 receptors. Certain neurosteroids are known to interact with σ1 receptors, and have been proposed to be their endogenous ligands. These receptors are located in the plasma membrane and in subcellular membranes, particularly in the endoplasmic reticulum, where they play a modulatory role in intracellular Ca2+ signaling. Sigma1 receptors also play a modulatory role in the activity of some ion channels and in several neurotransmitter systems, mainly in glutamatergic neurotransmission. In accordance with their widespread modulatory role, σ1 receptor ligands have been proposed to be useful in several therapeutic fields such as amnesic and cognitive deficits, depression and anxiety, schizophrenia, analgesia, and against some effects of drugs of abuse (such as cocaine and methamphetamine). In this review we provide an overview of the present knowledge of σ1 receptors, focussing on σ1 ligand neuropharmacology and the role of σ1 receptors in behavioral animal studies, which have contributed greatly to the potential therapeutic applications of σ1 ligands.
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Affiliation(s)
- E J Cobos
- Department of Pharmacology and Institute of Neuroscience, Faculty of Medicine, University of Granada, Granada, Spain
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Rybczynska AA, Elsinga PH, Sijbesma JW, Ishiwata K, de Jong JR, de Vries EF, Dierckx RA, van Waarde A. Steroid hormones affect binding of the sigma ligand 11C-SA4503 in tumour cells and tumour-bearing rats. Eur J Nucl Med Mol Imaging 2009; 36:1167-75. [PMID: 19247652 PMCID: PMC2691528 DOI: 10.1007/s00259-009-1076-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2008] [Accepted: 01/16/2009] [Indexed: 11/28/2022]
Abstract
Purpose Sigma receptors are implicated in memory and cognitive functions, drug addiction, depression and schizophrenia. In addition, sigma receptors are strongly overexpressed in many tumours. Although the natural ligands are still unknown, steroid hormones are potential candidates. Here, we examined changes in binding of the sigma-1 agonist 11C-SA4503 in C6 glioma cells and in living rats after modification of endogenous steroid levels. Methods 11C-SA4503 binding was assessed in C6 monolayers by gamma counting and in anaesthetized rats by microPET scanning. C6 cells were either repeatedly washed and incubated in steroid-free medium or exposed to five kinds of exogenous steroids (1 h or 5 min before tracer addition, respectively). Tumour-bearing male rats were repeatedly treated with pentobarbital (a condition known to result in reduction of endogenous steroid levels) or injected with progesterone. Results Binding of 11C-SA4503 to C6 cells was increased (~50%) upon removal and decreased (~60%) upon addition of steroid hormones (rank order of potency: progesterone > allopregnanolone = testosterone = androstanolone > dehydroepiandrosterone-3-sulphate, IC50 progesterone 33 nM). Intraperitoneally administered progesterone reduced tumour uptake and tumour-to-muscle contrast (36%). Repeated treatment of animals with pentobarbital increased the PET standardized uptake value of 11C-SA4503 in tumour (16%) and brain (27%), whereas the kinetics of blood pool radioactivity was unaffected. Conclusions The binding of 11C-SA4503 is sensitive to steroid competition. Since not only increases but also decreases of steroid levels affect ligand binding, a considerable fraction of the sigma-1 receptor population in cultured tumour cells or tumour-bearing animals is normally occupied by endogenous steroids.
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Affiliation(s)
- Anna A Rybczynska
- Nuclear Medicine and Molecular Imaging, University of Groningen Medical Center, University of Groningen, Hanzeplein 1, 9713GZ, Groningen, The Netherlands.
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Martin-Fardon R, Maurice T, Aujla H, Bowen WD, Weiss F. Differential effects of sigma1 receptor blockade on self-administration and conditioned reinstatement motivated by cocaine vs natural reward. Neuropsychopharmacology 2007; 32:1967-73. [PMID: 17268407 DOI: 10.1038/sj.npp.1301323] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Growing evidence suggests a role for sigma(1) (sigma(1)) receptors in cognitive function, anxiety, depression, regulation of stress responses, and, recently, the appetitive effects of cocaine as measured by conditioned place preference. This study was designed to extend understanding of the role of sigma(1) receptors in addiction-relevant conditioned effects of cocaine by testing the effects of a potent and selective sigma(1) receptor antagonist, BD1047, on conditioned reinstatement of cocaine-seeking. To determine whether modification of conditioned reinstatement by BD1047 is selective for drug-directed behavior or reflects general suppressant effects on motivated behavior, BD1047 was tested also on reinstatement induced by stimuli conditioned to a natural reward, sweetened condensed milk (SCM). Additionally, because sigma(1) receptors have been implicated also in processes linked to the acute reinforcing actions of cocaine, tests of the effects of BD1047 on cocaine self-administration-including a comparison with the sigma(1) antagonist effects on SCM self-administration-were conducted as well. Cocaine self-administering male Wistar rats were trained to associate a discriminative stimulus (S(D)) with the availability of cocaine or SCM, and then subjected to reinstatement tests following extinction of cocaine or SCM-reinforced behavior. BD1047 (1-30 mg/kg) reversed response reinstatement induced by the cocaine S(D) at 20 and 30 mg/kg but did not modify SCM S(D)-induced responding at all but the highest 30 mg dose, at which responding was reversed to extinction levels. BD1047 did not modify responding reinforced directly by SCM or cocaine. The findings support a role for sigma(1) receptors in regulating conditioned responses to cocaine-related contextual stimuli and identify this receptor as a potential treatment target for the prevention of craving and relapse.
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Affiliation(s)
- Rémi Martin-Fardon
- Molecular and Integrative Neurosciences Department, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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Frye CA. Progestins influence motivation, reward, conditioning, stress, and/or response to drugs of abuse. Pharmacol Biochem Behav 2007; 86:209-19. [PMID: 16979750 PMCID: PMC3613144 DOI: 10.1016/j.pbb.2006.07.033] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2006] [Revised: 06/09/2006] [Accepted: 07/25/2006] [Indexed: 01/18/2023]
Abstract
Progesterone (pregn-4-ene-3,20-dione; P) and its metabolite 5alpha-pregnan-3alpha-ol-20-one (3alpha,5alpha-THP) are secreted by ovaries, adrenals, and glial cells. 3alpha,5alpha-THP in the midbrain ventral tegmental area mediates sexual receptivity of rodents through its actions at GABA(A), NMDA, and/or D(1) receptors. The extent to which 3alpha,5alpha-THP may influence anti-anxiety/anti-stress effects, conditioning and/or reward through these substrates and/or by altering hypothalamic pituitary adrenal axis function is discussed. Biosynthesis of 3alpha,5alpha-THP occurs in responses to mating and may underlie some of the rewarding aspects of sexual behavior. Recent findings from our laboratory which demonstrate that progestins can enhance approach to novel stimuli, conditioning, and reinforcement are reviewed. How progestins' effects on these processes may underlie response to drugs of abuse is considered and new findings which demonstrate interactions between progestins and cocaine are presented.
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Affiliation(s)
- Cheryl A Frye
- Department of Psychology, Centers for Neuroscience and Life Sciences Research, The University at Albany, NY 12222, USA.
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Monnet FP, Maurice T. The Sigma1 Protein as a Target for the Non-genomic Effects of Neuro(active)steroids: Molecular, Physiological, and Behavioral Aspects. J Pharmacol Sci 2006; 100:93-118. [PMID: 16474209 DOI: 10.1254/jphs.cr0050032] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Steroids synthesized in the periphery or de novo in the brain, so called 'neurosteroids', exert both genomic and nongenomic actions on neurotransmission systems. Through rapid modulatory effects on neurotransmitter receptors, they influence inhibitory and excitatory neurotransmission. In particular, progesterone derivatives like 3alpha-hydroxy-5alpha-pregnan-20-one (allopregnanolone) are positive allosteric modulators of the gamma-aminobutyric acid type A (GABA(A)) receptor and therefore act as inhibitory steroids, while pregnenolone sulphate (PREGS) and dehydroepiandrosterone sulphate (DHEAS) are negative modulators of the GABA(A) receptor and positive modulators of the N-methyl-D-aspartate (NMDA) receptor, therefore acting as excitatory neurosteroids. Some steroids also interact with atypical proteins, the sigma (sigma) receptors. Recent studies particularly demonstrated that the sigma1 receptor contributes effectively to their pharmacological actions. The present article will review the data demonstrating that the sigma1 receptor binds neurosteroids in physiological conditions. The physiological relevance of this interaction will be analyzed and the impact on physiopathological outcomes in memory and drug addiction will be illustrated. We will particularly highlight, first, the importance of the sigma1-receptor activation by PREGS and DHEAS which may contribute to their modulatory effect on calcium homeostasis and, second, the importance of the steroid tonus in the pharmacological development of selective sigma1 drugs.
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Affiliation(s)
- François P Monnet
- Unité 705 de l'Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche 7157 du Centre National de la Recherche Scientifique, Université de Paris V et VII, Hôpital Lariboisière-Fernand Widal, Paris, France
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