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Reddy DS. Neurosteroids as Novel Anticonvulsants for Refractory Status Epilepticus and Medical Countermeasures for Nerve Agents: A 15-Year Journey to Bring Ganaxolone from Bench to Clinic. J Pharmacol Exp Ther 2024; 388:273-300. [PMID: 37977814 PMCID: PMC10801762 DOI: 10.1124/jpet.123.001816] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 10/05/2023] [Accepted: 10/23/2023] [Indexed: 11/19/2023] Open
Abstract
This article describes recent advances in the use of neurosteroids as novel anticonvulsants for refractory status epilepticus (RSE) and as medical countermeasures (MCs) for organophosphates and chemical nerve agents (OPNAs). We highlight a comprehensive 15-year journey to bring the synthetic neurosteroid ganaxolone (GX) from bench to clinic. RSE, including when caused by nerve agents, is associated with devastating morbidity and permanent long-term neurologic dysfunction. Although recent approval of benzodiazepines such as intranasal midazolam and intranasal midazolam offers improved control of acute seizures, novel anticonvulsants are needed to suppress RSE and improve neurologic function outcomes. Currently, few anticonvulsant MCs exist for victims of OPNA exposure and RSE. Standard-of-care MCs for postexposure treatment include benzodiazepines, which do not effectively prevent or mitigate seizures resulting from nerve agent intoxication, leaving an urgent unmet medical need for new anticonvulsants for RSE. Recently, we pioneered neurosteroids as next-generation anticonvulsants that are superior to benzodiazepines for treatment of OPNA intoxication and RSE. Because GX and related neurosteroids that activate extrasynaptic GABA-A receptors rapidly control seizures and offer robust neuroprotection by reducing neuronal damage and neuroinflammation, they effectively improve neurologic outcomes after acute OPNA exposure and RSE. GX has been selected for advanced, Biomedical Advanced Research and Development Authority-supported phase 3 trials of RSE and nerve agent seizures. In addition, in mechanistic studies of neurosteroids at extrasynaptic receptors, we identified novel synthetic analogs with features that are superior to GX for current medical needs. Development of new MCs for RSE is complex, tedious, and uncertain due to scientific and regulatory challenges. Thus, further research will be critical to fill key gaps in evaluating RSE and anticonvulsants in vulnerable (pediatric and geriatric) populations and military persons. SIGNIFICANCE STATEMENT: Following organophosphate and nerve agent intoxication, refractory status epilepticus (RSE) occurs despite benzodiazepine treatment. RSE occurs in 40% of status epilepticus patients, with a 35% mortality rate and significant neurological morbidity in survivors. To treat RSE, neurosteroids are better anticonvulsants than benzodiazepines. Our pioneering use of neurosteroids for RSE and nerve agents led us to develop ganaxolone as a novel anticonvulsant and neuroprotectant with significantly improved neurological outcomes. This article describes the bench-to-bedside journey of bringing neurosteroid therapy to patients, with ganaxolone leading the way.
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Affiliation(s)
- Doodipala Samba Reddy
- Department of Neuroscience and Experimental Therapeutics, Texas A&M University School of Medicine, Bryan, Texas and Institute of Pharmacology and Neurotherapeutics, Texas A&M University Health Science Center, Bryan, Texas
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2
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Chen D, Huang J, Xiao S, Cheng G, Liu Y, Zhao T, Chen C, Yi Y, Peng Y, Cao J. Synthesis, anti-leukemia activity, and molecular docking of novel 3,16-androstenedione derivatives. Steroids 2023; 199:109290. [PMID: 37549776 DOI: 10.1016/j.steroids.2023.109290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 07/30/2023] [Accepted: 08/02/2023] [Indexed: 08/09/2023]
Abstract
In this study, we synthesized androsta-4,14-diene-3,16-dione, 12β-hydroxyandrosta-4,14-diene-3,16-dione, and other 3,16-androstenedione derivatives from commercially available dehydroepiandrosterone as a starting material in 9-13 steps with high yields. The bioactivity of the obtained compounds was evaluated. Compounds 14a and 23a were shown to have high antitumor activity against acute lymphoblastic leukemia cell lines Nalm-6 and BALL-1, respectively. Network pharmacology analysis showed that the anti-leukemia activity of compounds 14a and 23a might be related to the JAK2, ABL1 protein, and PI3K/Akt signaling pathways. The molecular docking of compounds 14a and 23a identified possible active sites, with the lowest docking scores for PTGS2 and MAPK14, respectively. In addition, the absorption, distribution, metabolism, and excretion prediction results revealed the drug-likeness of the two compounds. Therefore, compounds 14a and 23a should be considered anti-leukemia candidates in future studies.
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Affiliation(s)
- Dongjie Chen
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Jiaying Huang
- Key Laboratory of Applied Chemistry of Chongqing Municipality, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Shanshan Xiao
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Guiguang Cheng
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Yaping Liu
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Tianrui Zhao
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Caixia Chen
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Yongxin Yi
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Yungui Peng
- Key Laboratory of Applied Chemistry of Chongqing Municipality, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
| | - Jianxin Cao
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China.
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3
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Covey DF, Evers AS, Izumi Y, Maguire JL, Mennerick SJ, Zorumski CF. Neurosteroid enantiomers as potentially novel neurotherapeutics. Neurosci Biobehav Rev 2023; 149:105191. [PMID: 37085023 PMCID: PMC10750765 DOI: 10.1016/j.neubiorev.2023.105191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 04/17/2023] [Accepted: 04/18/2023] [Indexed: 04/23/2023]
Abstract
Endogenous neurosteroids and synthetic neuroactive steroids (NAS) are important targets for therapeutic development in neuropsychiatric disorders. These steroids modulate major signaling systems in the brain and intracellular processes including inflammation, cellular stress and autophagy. In this review, we describe studies performed using unnatural enantiomers of key neurosteroids, which are physiochemically identical to their natural counterparts except for rotation of polarized light. These studies led to insights in how NAS interact with receptors, ion channels and intracellular sites of action. Certain effects of NAS show high enantioselectivity, consistent with actions in chiral environments and likely direct interactions with signaling proteins. Other effects show no enantioselectivity and even reverse enantioselectivity. The spectrum of effects of NAS enantiomers raises the possibility that these agents, once considered only as tools for preclinical studies, have therapeutic potential that complements and in some cases may exceed their natural counterparts. Here we review studies of NAS enantiomers from the perspective of their potential development as novel neurotherapeutics.
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Affiliation(s)
- Douglas F Covey
- Departments of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA; Anesthesiology Washington University School of Medicine, St. Louis, MO, USA; The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, MO, USA
| | - Alex S Evers
- Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA; Anesthesiology Washington University School of Medicine, St. Louis, MO, USA; The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, MO, USA
| | - Yukitoshi Izumi
- Departments of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, MO, USA
| | - Jamie L Maguire
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA
| | - Steven J Mennerick
- Departments of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, MO, USA
| | - Charles F Zorumski
- Departments of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, MO, USA.
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4
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Elsayed OH, El-Mallakh RS. Catatonia Secondary to Depolarization Block. Asian J Psychiatr 2023; 84:103543. [PMID: 37028234 DOI: 10.1016/j.ajp.2023.103543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 02/18/2023] [Accepted: 03/13/2023] [Indexed: 04/09/2023]
Abstract
Catatonia is a severe psychomotor disorder that is associated with a 60-fold increased risk of premature death. Its occurrence has been associated with multiple psychiatric diagnoses, the most common being type I bipolar disorder. Catatonia can be understood as a disorder of ion dysregulation with reduced clearance of intracellular sodium ions. As the intraneuronal sodium concentration increases, the transmembrane potential is increased, and the resting potential may ultimately depolarize above the cellular threshold potential creating a condition known as depolarization block. Neurons in depolarization block do not respond to stimulation but are constantly releasing neurotransmitter; they mirror the clinical state of catatonia - active but non-responsive. Hyperpolarizing neurons, e.g., with benzodiazepines, is the most effective treatment.
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Affiliation(s)
- Omar H Elsayed
- Mood Disorders Research Program, Depression Center, Department of Psychiatry and Behavioral Sciences, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Rif S El-Mallakh
- Mood Disorders Research Program, Depression Center, Department of Psychiatry and Behavioral Sciences, University of Louisville School of Medicine, Louisville, KY 40202, USA.
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5
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Synthesis of diosgenin derivatives by A and B ring modifications and low-valent titanium (Ti0)-catalysed McMurry coupling reactions and designing to create novel biological agents. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.132511] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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6
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Zorumski CF, Paul SM, Covey DF, Mennerick S. Neurosteroids as novel antidepressants and anxiolytics: GABA-A receptors and beyond. Neurobiol Stress 2019; 11:100196. [PMID: 31649968 PMCID: PMC6804800 DOI: 10.1016/j.ynstr.2019.100196] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 09/24/2019] [Indexed: 01/22/2023] Open
Abstract
The recent FDA approval of the neurosteroid, brexanolone (allopregnanolone), as a treatment for women with postpartum depression, and successful trials of a related neuroactive steroid, SGE-217, for men and women with major depressive disorder offer the hope of a new era in treating mood and anxiety disorders based on the potential of neurosteroids as modulators of brain function. This review considers potential mechanisms contributing to antidepressant and anxiolytic effects of allopregnanolone and other GABAergic neurosteroids focusing on their actions as positive allosteric modulators of GABAA receptors. We also consider their roles as endogenous "stress" modulators and possible additional mechanisms contributing to their therapeutic effects. We argue that further understanding of the molecular, cellular, network and psychiatric effects of neurosteroids offers the hope of further advances in the treatment of mood and anxiety disorders.
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Affiliation(s)
- Charles F. Zorumski
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA
- The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, MO, USA
| | - Steven M. Paul
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
- The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, MO, USA
| | - Douglas F. Covey
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
- The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, MO, USA
| | - Steven Mennerick
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA
- The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, MO, USA
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7
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Antkowiak B, Rammes G. GABA(A) receptor-targeted drug development -New perspectives in perioperative anesthesia. Expert Opin Drug Discov 2019; 14:683-699. [DOI: 10.1080/17460441.2019.1599356] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Bernd Antkowiak
- Department of Anesthesiology and Intensive Care, Experimental Anesthesiology Section, Eberhard-Karls-University,
Tübingen, Germany
- Department of Anaesthesiology and Intensive Care, Experimental Anaesthesiology Section, Werner Reichardt Center for Integrative Neuroscience, Tübingen,
Germany
| | - Gerhard Rammes
- University Hospital rechts der Isar, Department of Anesthesiology, München,
Germany
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8
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Shiina I, Miesch M, Peter C, Geoffroy P, Murata T, Tonoi T. Diastereo–/Enantioselective Diels–Alder Synthesis of 14β-Hydroxysteroid Scaffolds: A Combined Experimental and DFT Study. HETEROCYCLES 2019. [DOI: 10.3987/com-18-s(f)99] [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: 11/19/2022]
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9
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Okolo C, Ali MA, Newman M, Chambers SA, Whitt J, Alsharif ZA, Day VW, Alam MA. Hexafluoroisopropanol-Mediated Domino Reaction for the Synthesis of Thiazolo-androstenones: Potent Anticancer Agents. ACS OMEGA 2018; 3:17991-18001. [PMID: 30613817 PMCID: PMC6312635 DOI: 10.1021/acsomega.8b02840] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 12/12/2018] [Indexed: 05/02/2023]
Abstract
A cascade reaction of thioamides with 6β-bromoandrostenedione in hexafluoroisopropanol formed substituted thiazolo-androstenones. This is a simple and mild protocol to synthesize novel molecules by using readily available reagents and substrates. Feasibility of the reaction has been rationalized by density functional theory calculations. Moreover, these compounds are potent growth inhibitors of colon, central nervous system, melanoma, ovarian, and renal cancer cell lines with 50% growth inhibition values as low as 1.04 μM.
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Affiliation(s)
- ChrisTina Okolo
- Department
of Chemistry and Physics, College of Science and Mathematics, Arkansas State University, Jonesboro, Arkansas 72467, United States
| | - Mohamad Akbar Ali
- Department
of Chemistry, Sejong University, Seoul 143-747, Republic of Korea
| | - Matthew Newman
- Department
of Chemistry and Physics, College of Science and Mathematics, Arkansas State University, Jonesboro, Arkansas 72467, United States
| | - Steven A. Chambers
- Department
of Chemistry and Physics, College of Science and Mathematics, Arkansas State University, Jonesboro, Arkansas 72467, United States
| | - Jedidiah Whitt
- Department
of Chemistry and Physics, College of Science and Mathematics, Arkansas State University, Jonesboro, Arkansas 72467, United States
| | - Zakeyah A. Alsharif
- Department
of Chemistry and Physics, College of Science and Mathematics, Arkansas State University, Jonesboro, Arkansas 72467, United States
| | - Victor W. Day
- Department
of Chemistry, Integrated Science Building, University of Kansas, Lawrence, Kansas 66046, United States
| | - Mohammad A. Alam
- Department
of Chemistry and Physics, College of Science and Mathematics, Arkansas State University, Jonesboro, Arkansas 72467, United States
- E-mail:
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10
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Ali MA, Okolo C, Alsharif ZA, Whitt J, Chambers SA, Varma RS, Alam MA. Benign Synthesis of Thiazolo-androstenone Derivatives as Potent Anticancer Agents. Org Lett 2018; 20:5927-5932. [PMID: 30204455 DOI: 10.1021/acs.orglett.8b02587] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
An unprecedented reaction of thiourea derivatives with 6β-bromoandrostenedione has been discovered for the formation of aminothiazolo-androstenones via a simple, safer, cascade protocol that enables the syntheses of novel molecules by using readily available reagents. The reaction mechanism of product formation has been rationalized by density functional theory calculations. This benign methodology accentuates a domino protocol deploying a renewable solvent, ethanol, while generating novel compounds that display potent growth inhibitory effects in in vitro studies for several cancer cell lines at submicromolar concentrations.
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Affiliation(s)
- Mohamad Akbar Ali
- Department of Chemistry , Sejong University , Seoul 143-747 , Republic of Korea
| | - ChrisTina Okolo
- Department of Chemistry and Physics, College of Science and Mathematics , Arkansas State University , Jonesboro , Arkansas 72467 , United States
| | - Zakeyah A Alsharif
- Department of Chemistry and Physics, College of Science and Mathematics , Arkansas State University , Jonesboro , Arkansas 72467 , United States
| | - Jedidiah Whitt
- Department of Chemistry and Physics, College of Science and Mathematics , Arkansas State University , Jonesboro , Arkansas 72467 , United States
| | - Steven A Chambers
- Department of Chemistry and Physics, College of Science and Mathematics , Arkansas State University , Jonesboro , Arkansas 72467 , United States
| | - Rajender S Varma
- Regional Center of Advanced Technologies and Materials, Faculty of Science , Palacký University , Olomouc, Šlechtitelů 27 , 783 71 Olomouc , Czech Republic
| | - Mohammad A Alam
- Department of Chemistry and Physics, College of Science and Mathematics , Arkansas State University , Jonesboro , Arkansas 72467 , United States
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11
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Chuang SH, Reddy DS. 3 β-Methyl-Neurosteroid Analogs Are Preferential Positive Allosteric Modulators and Direct Activators of Extrasynaptic δ-Subunit γ-Aminobutyric Acid Type A Receptors in the Hippocampus Dentate Gyrus Subfield. J Pharmacol Exp Ther 2018; 365:583-601. [PMID: 29602830 DOI: 10.1124/jpet.117.246660] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 03/28/2018] [Indexed: 02/06/2023] Open
Abstract
Neurosteroids are powerful modulators of γ-aminobutyric acid (GABA)-A receptors. Ganaxolone (3α-hydroxy-3β-methyl-5α-pregnan-20-one, GX) and synthetic analogs of the neurosteroid allopregnanolone (AP) are designed to treat epilepsy and related conditions. However, their precise mechanism of action in native neurons remains unclear. Here, we sought to determine the mode of action of GX and its analogs at GABA-A receptors in native hippocampal neurons by analyzing extrasynaptic receptor-mediated tonic currents and synaptic receptor-mediated phasic currents. Concentration-response profiles of GX were determined in two cell types: δ-containing dentate gyrus granule cells (DGGCs) and γ2-containing CA1 pyramidal cells (CA1PCs). GX produced significantly greater potentiation of the GABA-A receptor-activated chloride currents in DGGCs (500%) than CA1PCs (200%). In the absence of GABA, GX evoked 2-fold greater inward currents in DGGCs than CA1PCs, which were 2-fold greater than AP within DGGCs. In hippocampus slices, GX potentiated and directly activated tonic currents in DGGCs. These responses were significantly diminished in DGGCs from δ-subunit knockout (δKO) mice, confirming GX's selectivity for δGABA-A receptors. Like AP, GX potentiation of tonic currents was prevented by protein kinase C inhibition. Furthermore, GX's protection against hippocampus-kindled seizures was significantly diminished in δKO mice. GX analogs exhibited greater potency and efficacy than GX on δGABA-A receptor-mediated tonic inhibition. In summary, these results provide strong evidence that GX and its analogs are preferential allosteric modulators and direct activators of extrasynaptic δGABA-A receptors regulating network inhibition and seizures in the dentate gyrus. Therefore, these findings provide a mechanistic rationale for the clinical use of synthetic neurosteroids in epilepsy and seizure disorders.
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Affiliation(s)
- Shu-Hui Chuang
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas
| | - Doodipala Samba Reddy
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas
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12
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Cai H, Cao T, Zhou X, Yao JK. Neurosteroids in Schizophrenia: Pathogenic and Therapeutic Implications. Front Psychiatry 2018; 9:73. [PMID: 29568275 PMCID: PMC5852066 DOI: 10.3389/fpsyt.2018.00073] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 02/21/2018] [Indexed: 12/11/2022] Open
Abstract
Neurosteroids are a group of important endogenous molecules affecting many neural functions in the brain. Increasing evidence suggests a possible role of these neurosteroids in the pathology and symptomatology of schizophrenia (SZ) and other mental disorders. The aim of this review is to summarize the current knowledge about the neural functions of neurosteroids in the brain, and to evaluate the role of the key neurosteroids as candidate modulators in the etiology and therapeutics of SZ. The present paper provides a brief introduction of neurosteroid metabolism and distribution, followed by a discussion of the mechanisms underlying neurosteroid actions in the brain. The content regarding the modulation of the GABAA receptor is elaborated, given the considerable knowledge of its interactions with other neurotransmitter and neuroprotective systems, as well as its ameliorating effects on stress that may play a role in the SZ pathophysiology. In addition, several preclinical and clinical studies suggested a therapeutic benefit of neurosteroids in SZ patients, even though the presence of altered neurosteroid pathways in the circulating blood and/or brain remains debatable. Following treatment of antipsychotic drugs in SZ, therapeutic benefits have also been linked to the regulation of neurosteroid signaling. Specifically, the neurosteroids such as pregnenolone and dehydroepiandrosterone affect a broad spectrum of behavioral functions through their unique molecular characteristics and may represent innovative therapeutic targets for SZ. Future investigations in larger cohorts with long-term follow-ups will be required to ascertain the neuropsychopharmacological role of this yet unexploited class of neurosteroid agents.
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Affiliation(s)
- HuaLin Cai
- Department of Pharmacy, The Second Xiangya Hospital of Central South University, Changsha, China
- The Institute of Clinical Pharmacy, Central South University, Changsha, China
| | - Ting Cao
- Department of Pharmacy, The Second Xiangya Hospital of Central South University, Changsha, China
- The Institute of Clinical Pharmacy, Central South University, Changsha, China
| | - Xiang Zhou
- Medical Research Service, VA Pittsburgh Healthcare System, Pittsburgh, PA, United States
- Department of Pharmaceutical Sciences, University of Pittsburgh School of Pharmacy, Pittsburgh, PA, United States
| | - Jeffrey K. Yao
- Medical Research Service, VA Pittsburgh Healthcare System, Pittsburgh, PA, United States
- Department of Pharmaceutical Sciences, University of Pittsburgh School of Pharmacy, Pittsburgh, PA, United States
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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13
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Reddy DS. GABA-A Receptors Mediate Tonic Inhibition and Neurosteroid Sensitivity in the Brain. VITAMINS AND HORMONES 2018; 107:177-191. [PMID: 29544630 DOI: 10.1016/bs.vh.2017.12.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Neurosteroids like allopregnanolone (AP) are positive allosteric modulators of synaptic and extrasynaptic GABA-A receptors. AP and related neurosteroids exhibit a greater potency for δ-containing extrasynaptic receptors. The δGABA-A receptors, which are expressed extrasynaptically in the dentate gyrus and other regions, contribute to tonic inhibition, promoting network shunting as well as reducing seizure susceptibility. Levels of endogenous neurosteroids fluctuate with ovarian cycle. Natural and synthetic neurosteroids maximally potentiate tonic inhibition in the hippocampus and provide robust protection against a variety of limbic seizures and status epilepticus. Recently, a consensus neurosteroid pharmacophore model has been proposed at extrasynaptic δGABA-A receptors based on structure-activity relationship for functional activation of tonic currents and seizure protection. Aside from anticonvulsant actions, neurosteroids have been found to be powerful anxiolytic and anesthetic agents. Neurosteroids and Zn2+ have preferential affinity for δ-containing receptors. Thus, Zn2+ can prevent neurosteroid activation of extrasynaptic δGABA-A receptor-mediated tonic inhibition. Recently, we demonstrated that Zn2+ selectively inhibits extrasynaptic δGABA-A receptors and thereby fully prevents AP activation of tonic inhibition and seizure protection. We confirmed that neurosteroids exhibit greater sensitivity at extrasynaptic δGABA-A receptors. Overall, extrasynaptic GABA-A receptors are primary mediators of tonic inhibition in the brain and play a key role in the pathophysiology of epilepsy and other neurological disorders.
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Affiliation(s)
- Doodipala Samba Reddy
- College of Medicine, Texas A&M University Health Science Center, Bryan, TX, United States.
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14
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Sparling BA, DiMauro EF. Progress in the discovery of small molecule modulators of the Cys-loop superfamily receptors. Bioorg Med Chem Lett 2017; 27:3207-3218. [DOI: 10.1016/j.bmcl.2017.04.073] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2017] [Revised: 04/20/2017] [Accepted: 04/24/2017] [Indexed: 12/11/2022]
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15
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Moosmann P, Ueoka R, Grauso L, Mangoni A, Morinaka BI, Gugger M, Piel J. Cyanobacterial ent
-Sterol-Like Natural Products from a Deviated Ubiquinone Pathway. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201611617] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Philipp Moosmann
- Institut für Mikrobiologie; Eidgenössiche Technische Hochschule (ETH) Zürich; Vladimir-Prelog-Weg 4 8093 Zürich Switzerland
| | - Reiko Ueoka
- Institut für Mikrobiologie; Eidgenössiche Technische Hochschule (ETH) Zürich; Vladimir-Prelog-Weg 4 8093 Zürich Switzerland
| | - Laura Grauso
- Dipartimento di Farmacia Università di Napoli Federico II; Università di Napoli Federico II; via D. Montesano 49 80131 Napoli Italy
- Current address: Stazione Zoologica Anton Dohrn; Villa Comunale 80121 Napoli Italy
| | - Alfonso Mangoni
- Dipartimento di Farmacia Università di Napoli Federico II; Università di Napoli Federico II; via D. Montesano 49 80131 Napoli Italy
| | - Brandon I. Morinaka
- Institut für Mikrobiologie; Eidgenössiche Technische Hochschule (ETH) Zürich; Vladimir-Prelog-Weg 4 8093 Zürich Switzerland
| | - Muriel Gugger
- Institut Pasteur; Collection des Cyanobactéries; Département de Microbiologie; 75015 Paris France
| | - Jörn Piel
- Institut für Mikrobiologie; Eidgenössiche Technische Hochschule (ETH) Zürich; Vladimir-Prelog-Weg 4 8093 Zürich Switzerland
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16
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Moosmann P, Ueoka R, Grauso L, Mangoni A, Morinaka BI, Gugger M, Piel J. Cyanobacterial ent
-Sterol-Like Natural Products from a Deviated Ubiquinone Pathway. Angew Chem Int Ed Engl 2017; 56:4987-4990. [DOI: 10.1002/anie.201611617] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 01/19/2017] [Indexed: 12/30/2022]
Affiliation(s)
- Philipp Moosmann
- Institut für Mikrobiologie; Eidgenössiche Technische Hochschule (ETH) Zürich; Vladimir-Prelog-Weg 4 8093 Zürich Switzerland
| | - Reiko Ueoka
- Institut für Mikrobiologie; Eidgenössiche Technische Hochschule (ETH) Zürich; Vladimir-Prelog-Weg 4 8093 Zürich Switzerland
| | - Laura Grauso
- Dipartimento di Farmacia Università di Napoli Federico II; Università di Napoli Federico II; via D. Montesano 49 80131 Napoli Italy
- Current address: Stazione Zoologica Anton Dohrn; Villa Comunale 80121 Napoli Italy
| | - Alfonso Mangoni
- Dipartimento di Farmacia Università di Napoli Federico II; Università di Napoli Federico II; via D. Montesano 49 80131 Napoli Italy
| | - Brandon I. Morinaka
- Institut für Mikrobiologie; Eidgenössiche Technische Hochschule (ETH) Zürich; Vladimir-Prelog-Weg 4 8093 Zürich Switzerland
| | - Muriel Gugger
- Institut Pasteur; Collection des Cyanobactéries; Département de Microbiologie; 75015 Paris France
| | - Jörn Piel
- Institut für Mikrobiologie; Eidgenössiche Technische Hochschule (ETH) Zürich; Vladimir-Prelog-Weg 4 8093 Zürich Switzerland
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17
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Wu XY, Wang YL, Hai L, Gong P, Wu Y. A new and efficient method for the synthesis of rocuronium bromide. CHINESE CHEM LETT 2017. [DOI: 10.1016/j.cclet.2016.10.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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18
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Qian M, Engler-Chiurazzi EB, Lewis SE, Rath NP, Simpkins JW, Covey DF. Structure-activity studies of non-steroid analogues structurally-related to neuroprotective estrogens. Org Biomol Chem 2016; 14:9790-9805. [PMID: 27714297 PMCID: PMC5525543 DOI: 10.1039/c6ob01726f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Estrone and 17β-estradiol are phenolic steroids that are known to be neuroprotective in multiple models of neuronal injury. Previous studies have identified the importance of their phenolic steroid A-ring for neuroprotection and have identified ortho substituents at the C-2 and C-4 positions on the phenol ring that enhance this activity. To investigate the importance of the steroid ring system for neuroprotective activity, phenolic compounds having the cyclopent[b]anthracene, cyclopenta[b]phenanthrene, benz[f]indene, benz[e]indene, indenes linked to a phenol, and a phenolic spiro ring system were prepared. New synthetic methods were developed to make some of the cyclopent[b]anthracene analogues as well as the spiro ring system. Compounds were evaluated for their ability to protect HT-22 hippocampal neurons from glutamate neurotoxicity and their activity relative to a potent neuroprotective analogue of 17β-estradiol was determined. An adamantyl substituent placed ortho to the phenolic hydroxyl group gave neuroprotective analogues in all ring systems studied.
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Affiliation(s)
- Mingxing Qian
- Department of Developmental Biology, Campus Box 8103, Washington University in St. Louis, School of Medicine, 660 S. Euclid Ave., St. Louis, MO 63110, USA.
| | | | - Sara E Lewis
- Center for Basic and Translational Stroke Research, West Virginia University, Morgantown, WV 26506, USA
| | - Nigam P Rath
- Department of Chemistry and Biochemistry and Center for Nanoscience, University of Missouri-St. Louis, St. Louis, MO 63121, USA
| | - James W Simpkins
- Center for Basic and Translational Stroke Research, West Virginia University, Morgantown, WV 26506, USA
| | - Douglas F Covey
- Department of Developmental Biology, Campus Box 8103, Washington University in St. Louis, School of Medicine, 660 S. Euclid Ave., St. Louis, MO 63110, USA. and Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110, USA and Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, USA
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19
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Drexler B, Balk M, Antkowiak B. Synergistic Modulation of γ-Aminobutyric Acid Type A Receptor-Mediated Synaptic Inhibition in Cortical Networks by Allopregnanolone and Propofol. Anesth Analg 2016; 123:877-83. [DOI: 10.1213/ane.0000000000001429] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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20
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Peter C, Ressault B, Geoffroy P, Miesch M. Concise Approach to (ent)-14 β-Hydroxysteroids through Highly Diastereo-/Enantioselective Diels-Alder Reactions. Chemistry 2016; 22:10808-12. [PMID: 27192692 DOI: 10.1002/chem.201601926] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Indexed: 11/07/2022]
Abstract
14β-Hydroxysteroids, especially 14β-hydroxyandrostane derivatives are closely related to the cardenolide skeletons. The latter were readily available through highly diastero/enantioselective Diels-Alder (DA) reactions requiring high pressure or Lewis acid activation. Moreover, in the presence of (R)- or (S)-carvone as a chiral dienophile, the DA-reaction takes place under chemodivergent parallel kinetic resolution control affording highly enantiomerically enriched 14β-hydroxysteroid derivatives or the corresponding (ent)-14β-hydroxysteroid derivatives.
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Affiliation(s)
- Clovis Peter
- Université de Strasbourg, Institut de Chimie - UMR 7177, 1 rue Blaise Pascal, BP296/R8-67008, Strasbourg Cedex, France
| | - Blandine Ressault
- Université de Strasbourg, Institut de Chimie - UMR 7177, 1 rue Blaise Pascal, BP296/R8-67008, Strasbourg Cedex, France
| | - Philippe Geoffroy
- Université de Strasbourg, Institut de Chimie - UMR 7177, 1 rue Blaise Pascal, BP296/R8-67008, Strasbourg Cedex, France
| | - Michel Miesch
- Université de Strasbourg, Institut de Chimie - UMR 7177, 1 rue Blaise Pascal, BP296/R8-67008, Strasbourg Cedex, France.
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21
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Reddy DS. Neurosteroids for the potential protection of humans against organophosphate toxicity. Ann N Y Acad Sci 2016; 1378:25-32. [PMID: 27450921 DOI: 10.1111/nyas.13160] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 04/29/2016] [Accepted: 06/01/2016] [Indexed: 12/18/2022]
Abstract
This article describes the therapeutic potential of neurosteroids as anticonvulsant antidotes for chemical intoxication caused by organophosphate pesticides and nerve agents or gases like sarin and soman. Toxic manifestations following nerve agent exposure, as evident in chemical attacks in Japan and Syria, include hypersecretion, respiratory distress, tremors, convulsions leading to status epilepticus (SE), and death. Benzodiazepines, such as diazepam, are the current anticonvulsants of choice for controlling nerve agent-induced life-threatening seizures, SE, and brain injury. Benzodiazepines can control acute seizures when given early, but they are less effective for delayed treatment of SE, which is characterized by rapid desensitization of synaptic GABAA receptors, benzodiazepine resistance, and brain injury. Neurosteroid-sensitive extrasynaptic GABAA receptors, however, remain unaffected by such events. Thus, anticonvulsant neurosteroids may produce more effective protection than benzodiazepines against a broad spectrum of chemical agents, even when given late after nerve agent exposure.
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Affiliation(s)
- Doodipala Samba Reddy
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas.
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22
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Reddy DS, Estes WA. Clinical Potential of Neurosteroids for CNS Disorders. Trends Pharmacol Sci 2016; 37:543-561. [PMID: 27156439 DOI: 10.1016/j.tips.2016.04.003] [Citation(s) in RCA: 126] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 04/02/2016] [Accepted: 04/05/2016] [Indexed: 11/27/2022]
Abstract
Neurosteroids are key endogenous molecules in the brain that affect many neural functions. We describe here recent advances in US National Institutes of Health (NIH)-sponsored and other clinical studies of neurosteroids for CNS disorders. The neuronal GABA-A receptor chloride channel is one of the prime molecular targets of neurosteroids. Allopregnanolone-like neurosteroids are potent allosteric agonists as well as direct activators of both synaptic and extrasynaptic GABA-A receptors. Hence, neurosteroids can maximally enhance synaptic phasic and extrasynaptic tonic inhibition. The resulting chloride current conductance generates a form of shunting inhibition that controls network excitability, seizures, and behavior. Such mechanisms of neurosteroids are providing innovative therapies for epilepsy, status epilepticus (SE), traumatic brain injury (TBI), fragile X syndrome (FXS), and chemical neurotoxicity. The neurosteroid field has entered a new era, and many compounds have reached advanced clinical trials. Synthetic analogs have several advantages over natural neurosteroids for clinical use because of their superior bioavailability and safety trends.
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Affiliation(s)
- Doodipala Samba Reddy
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, TX 77807, USA.
| | - William A Estes
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, TX 77807, USA
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23
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Jiang X, Shu HJ, Krishnan K, Qian M, Taylor AA, Covey DF, Zorumski CF, Mennerick S. A clickable neurosteroid photolabel reveals selective Golgi compartmentalization with preferential impact on proximal inhibition. Neuropharmacology 2016; 108:193-206. [PMID: 27114255 DOI: 10.1016/j.neuropharm.2016.04.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 03/18/2016] [Accepted: 04/21/2016] [Indexed: 11/18/2022]
Abstract
Anesthetic, GABA-active neurosteroids potently augment GABAA receptor function, leading to important behavioral consequences. Neurosteroids and their synthetic analogues are also models for a wide variety of cell-permeant neuroactive compounds. Cell permeation and compartmentalization raise the possibility that these compounds' actions are influenced by their cellular partitioning, but these contributions are not typically considered experimentally or therapeutically. To examine the interplay between cellular accumulation and pharmacodynamics of neurosteroids, we synthesized a novel chemical biology analogue (bio-active, clickable photolabel) of GABA-active neurosteroids. We discovered that the analogue selectively photo-labels neuronal Golgi in rat hippocampal neurons. The active analogue's selective distribution was distinct from endogenous cholesterol and not completely shared by some non-GABA active, neurosteroid-like analogues. On the other hand, the distribution was not enantioselective and did not require energy, in contrast to other recent precedents from the literature. We demonstrate that the soma-selective accumulation can act as a sink or source for steroid actions at plasma-membrane GABA receptors, altering steady-state and time course of effects at somatic GABAA receptors relative to dendritic receptors. Our results suggest a novel mechanism for compartment-selective drug actions at plasma-membrane receptors.
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Affiliation(s)
- Xiaoping Jiang
- Departments of Psychiatry, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
| | - Hong-Jin Shu
- Departments of Psychiatry, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
| | - Kathiresan Krishnan
- Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
| | - Mingxing Qian
- Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
| | - Amanda A Taylor
- Departments of Psychiatry, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
| | - Douglas F Covey
- Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA; Anesthesiology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA; Taylor Family Institute for Innovative Psychiatry Research, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
| | - Charles F Zorumski
- Departments of Psychiatry, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA; Neuroscience, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA; Taylor Family Institute for Innovative Psychiatry Research, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
| | - Steven Mennerick
- Departments of Psychiatry, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA; Neuroscience, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA; Taylor Family Institute for Innovative Psychiatry Research, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA.
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24
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Carver CM, Reddy DS. Neurosteroid Structure-Activity Relationships for Functional Activation of Extrasynaptic δGABA(A) Receptors. J Pharmacol Exp Ther 2016; 357:188-204. [PMID: 26857959 DOI: 10.1124/jpet.115.229302] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Accepted: 02/05/2016] [Indexed: 01/18/2023] Open
Abstract
Synaptic GABAA receptors are primary mediators of rapid inhibition in the brain and play a key role in the pathophysiology of epilepsy and other neurologic disorders. The δ-subunit GABAA receptors are expressed extrasynaptically in the dentate gyrus and contribute to tonic inhibition, promoting network shunting as well as reducing seizure susceptibility. However, the neurosteroid structure-function relationship at δGABA(A) receptors within the native hippocampus neurons remains unclear. Here we report a structure-activity relationship for neurosteroid modulation of extrasynaptic GABAA receptor-mediated tonic inhibition in the murine dentate gyrus granule cells. We recorded neurosteroid allosteric potentiation of GABA as well as direct activation of tonic currents using a wide array of natural and synthetic neurosteroids. Our results shows that, for all neurosteroids, the C3α-OH group remains obligatory for extrasynaptic receptor functional activity, as C3β-OH epimers were inactive in activating tonic currents. Allopregnanolone and related pregnane analogs exhibited the highest potency and maximal efficacy in promoting tonic currents. Alterations at the C17 or C20 region of the neurosteroid molecule drastically altered the transduction kinetics of tonic current activation. The androstane analogs had the weakest modulatory response among the analogs tested. Neurosteroid potentiation of tonic currents was completely (approximately 95%) diminished in granule cells from δ-knockout mice, suggesting that δ-subunit receptors are essential for neurosteroid activity. The neurosteroid sensitivity of δGABA(A) receptors was confirmed at the systems level using a 6-Hz seizure test. A consensus neurosteroid pharmacophore model at extrasynaptic δGABA(A) receptors is proposed based on a structure-activity relationship for activation of tonic current and seizure protection.
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Affiliation(s)
- Chase Matthew Carver
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas
| | - Doodipala Samba Reddy
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas
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25
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Chakrabarti S, Qian M, Krishnan K, Covey DF, Mennerick S, Akk G. Comparison of Steroid Modulation of Spontaneous Inhibitory Postsynaptic Currents in Cultured Hippocampal Neurons and Steady-State Single-Channel Currents from Heterologously Expressed α1β2γ2L GABA(A) Receptors. Mol Pharmacol 2016; 89:399-406. [PMID: 26769414 DOI: 10.1124/mol.115.102202] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 01/13/2016] [Indexed: 12/18/2022] Open
Abstract
Neuroactive steroids are efficacious modulators of γ-aminobutyric acid type A receptor (GABA(A)) receptor function. The effects of steroids on the GABA(A) receptor are typically determined by comparing steady-state single-channel open probability or macroscopic peak responses elicited by GABA in the absence and presence of a steroid. Due to differences in activation conditions (exposure duration, concentration of agonist), it is not obvious whether modulation measured using typical experimental protocols can be used to accurately predict the effect of a modulator on native receptors under physiologic conditions. In the present study, we examined the effects of 14 neuroactive steroids and analogs on the properties of spontaneous inhibitory postsynaptic currents (sIPSCs) in cultured rat hippocampal neurons. The goal was to determine whether the magnitude of modulation of the decay time course of sIPSCs correlates with the extent of modulation and kinetic properties of potentiation as determined in previous single-channel studies. The steroids were selected to cover a wide range of efficacy on heterologously expressed rat α1β2γ2L GABA(A) receptors, ranging from essentially inert to highly efficacious (strong potentiators of single-channel and macroscopic peak responses). The data indicate a strong correlation between prolongation of the decay time course of sIPSCs and potentiation of single-channel open probability. Furthermore, changes in intracluster closed time distributions were the single best predictor of prolongation of sIPSCs. We infer that the information obtained in steady-state single-channel recordings can be used to forecast modulation of synaptic currents.
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Affiliation(s)
- Sampurna Chakrabarti
- Department of Anesthesiology (S.C., G.A.), Department of Developmental Biology (M.Q., K.K., D.F.C.), and Department of Psychiatry (S.M.), and the Taylor Family Institute for Innovative Psychiatric Research (D.F.C., S.M., G.A.), Washington University School of Medicine, St. Louis, Missouri
| | - Mingxing Qian
- Department of Anesthesiology (S.C., G.A.), Department of Developmental Biology (M.Q., K.K., D.F.C.), and Department of Psychiatry (S.M.), and the Taylor Family Institute for Innovative Psychiatric Research (D.F.C., S.M., G.A.), Washington University School of Medicine, St. Louis, Missouri
| | - Kathiresan Krishnan
- Department of Anesthesiology (S.C., G.A.), Department of Developmental Biology (M.Q., K.K., D.F.C.), and Department of Psychiatry (S.M.), and the Taylor Family Institute for Innovative Psychiatric Research (D.F.C., S.M., G.A.), Washington University School of Medicine, St. Louis, Missouri
| | - Douglas F Covey
- Department of Anesthesiology (S.C., G.A.), Department of Developmental Biology (M.Q., K.K., D.F.C.), and Department of Psychiatry (S.M.), and the Taylor Family Institute for Innovative Psychiatric Research (D.F.C., S.M., G.A.), Washington University School of Medicine, St. Louis, Missouri
| | - Steven Mennerick
- Department of Anesthesiology (S.C., G.A.), Department of Developmental Biology (M.Q., K.K., D.F.C.), and Department of Psychiatry (S.M.), and the Taylor Family Institute for Innovative Psychiatric Research (D.F.C., S.M., G.A.), Washington University School of Medicine, St. Louis, Missouri
| | - Gustav Akk
- Department of Anesthesiology (S.C., G.A.), Department of Developmental Biology (M.Q., K.K., D.F.C.), and Department of Psychiatry (S.M.), and the Taylor Family Institute for Innovative Psychiatric Research (D.F.C., S.M., G.A.), Washington University School of Medicine, St. Louis, Missouri
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26
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Kasal A, Buděšínský M, Mareš P, Krištofíková Z, Leitão AJ, Sá e Melo ML, Silva MMC. Neurosteroids: Can a 2alpha,3alpha-epoxy ring make up for the 3alpha-hydroxyl group? Steroids 2016; 105:12-8. [PMID: 26631551 DOI: 10.1016/j.steroids.2015.11.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 11/06/2015] [Accepted: 11/19/2015] [Indexed: 10/22/2022]
Abstract
Seven steroid epoxides were prepared from 5α-pregn-2-en-20-one and 5α-pregn-3-en-20-one and their side-chain derivatives. All compounds were tested in vitro for binding to γ-aminobutyric acid (GABAA) receptor, some of them also in vivo for anticonvulsant action. 2α,3α-Epoxy-5α-pregnan-20-one inhibited the TBPS binding to the GABAA receptor and showed a moderate anticonvulsant action in immature rats. In contrast, its 3α,4α-isomer was inactive. More polar epoxide derivatives, modified at the side chain were less active or inactive. Noteworthy, diol 20, the product of trans-diaxial opening of the 2α,3α-epoxide 4, was not able to inhibit the TBPS binding, showing that the activity of the epoxide is due to the compound itself and not to its hydrolytic product. The 3α-hydroxyl group is known to be essential for the GABAA receptor binding. Despite the shortness of in vivo effects which are probably due to metabolic inactivation of the products prepared, our results show that the 2α,3α-epoxy ring is another structural pattern with ability to bind the GABAAR.
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Affiliation(s)
- Alexander Kasal
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Prague CZ16610, Czech Republic.
| | - Miloš Buděšínský
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Prague CZ16610, Czech Republic
| | - Pavel Mareš
- Institute of Physiology, Academy of Sciences, CZ14220 Prague 4, Czech Republic
| | - Zdena Krištofíková
- Alzheimer's Disease Center, National Institute of Mental Health, Klecany CZ25067, Czech Republic
| | - Alcino J Leitão
- Faculdade de Farmácia, Universidade de Coimbra, 3000-508 Coimbra, Portugal; CNC - Centre for Neurosciences and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
| | - Maria Luisa Sá e Melo
- Faculdade de Farmácia, Universidade de Coimbra, 3000-508 Coimbra, Portugal; CNC - Centre for Neurosciences and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
| | - Maria Manuel C Silva
- Faculdade de Farmácia, Universidade de Coimbra, 3000-508 Coimbra, Portugal; CNC - Centre for Neurosciences and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
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27
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Abstract
Neurosteroids, like allopregnanolone and pregnanolone, are endogenous regulators of neuronal excitability. Inside the brain, they are highly selective and potent modulators of GABAA receptor activity. Their anticonvulsant, anesthetics and anxiolytic properties are useful for the treatments of several neurological and psychiatric disorders via reducing the risks of side effects obtained with the commercial drugs. The principal disadvantages of endogenous neurosteroids administration are their rapid metabolism and their low oral bioavailability. Synthetic steroids analogues with major stability or endogenous neurosteroids stimulation synthesis might constitute promising novel strategies for the treatment of several disorders. Numerous studies indicate that the 3α-hydroxyl configuration is the key for binding and activity, but modifications in the steroid nucleus may emphasize different pharmacophores. So far, several synthetic steroids have been developed with successful neurosteroid-like effects. In this work, we summarize the properties of various synthetic steroids probed in trials throughout the analysis of several neurosteroids-like actions.
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Affiliation(s)
- Mariana Rey
- Laboratorio de Neurobiología, Instituto de Biología y Medicina Experimental (IBYME-CONICET), Vuelta de Obligado 2490, (C1428ADN) Ciudad Autónoma de Buenos Aires, Argentina
| | - Héctor Coirini
- Laboratorio de Neurobiología, Instituto de Biología y Medicina Experimental (IBYME-CONICET), Vuelta de Obligado 2490, (C1428ADN) Ciudad Autónoma de Buenos Aires, Argentina ; Departamento de Bioquímica Humana, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, Ciudad Autónoma de Buenos Aires, Argentina
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