1
|
Dembitsky VM. Steroids Bearing Heteroatom as Potential Drugs for Medicine. Biomedicines 2023; 11:2698. [PMID: 37893072 PMCID: PMC10604304 DOI: 10.3390/biomedicines11102698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 09/27/2023] [Accepted: 09/28/2023] [Indexed: 10/29/2023] Open
Abstract
Heteroatom steroids, a diverse class of organic compounds, have attracted significant attention in the field of medicinal chemistry and drug discovery. The biological profiles of heteroatom steroids are of considerable interest to chemists, biologists, pharmacologists, and the pharmaceutical industry. These compounds have shown promise as potential therapeutic agents in the treatment of various diseases, such as cancer, infectious diseases, cardiovascular disorders, and neurodegenerative conditions. Moreover, the incorporation of heteroatoms has led to the development of targeted drug delivery systems, prodrugs, and other innovative pharmaceutical approaches. Heteroatom steroids represent a fascinating area of research, bridging the fields of organic chemistry, medicinal chemistry, and pharmacology. The exploration of their chemical diversity and biological activities holds promise for the discovery of novel drug candidates and the development of more effective and targeted treatments.
Collapse
Affiliation(s)
- Valery M Dembitsky
- Centre for Applied Research, Innovation and Entrepreneurship, Lethbridge College, 3000 College Drive South, Lethbridge, AB T1K 1L6, Canada
| |
Collapse
|
2
|
Solomon VR, Tallapragada VJ, Chebib M, Johnston G, Hanrahan JR. GABA allosteric modulators: An overview of recent developments in non-benzodiazepine modulators. Eur J Med Chem 2019; 171:434-461. [DOI: 10.1016/j.ejmech.2019.03.043] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Revised: 02/17/2019] [Accepted: 03/17/2019] [Indexed: 01/13/2023]
|
3
|
High-throughput Screening in Larval Zebrafish Identifies Novel Potent Sedative-hypnotics. Anesthesiology 2019; 129:459-476. [PMID: 29894316 DOI: 10.1097/aln.0000000000002281] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
WHAT WE ALREADY KNOW ABOUT THIS TOPIC WHAT THIS ARTICLE TELLS US THAT IS NEW: BACKGROUND:: Many general anesthetics were discovered empirically, but primary screens to find new sedative-hypnotics in drug libraries have not used animals, limiting the types of drugs discovered. The authors hypothesized that a sedative-hypnotic screening approach using zebrafish larvae responses to sensory stimuli would perform comparably to standard assays, and efficiently identify new active compounds. METHODS The authors developed a binary outcome photomotor response assay for zebrafish larvae using a computerized system that tracked individual motions of up to 96 animals simultaneously. The assay was validated against tadpole loss of righting reflexes, using sedative-hypnotics of widely varying potencies that affect various molecular targets. A total of 374 representative compounds from a larger library were screened in zebrafish larvae for hypnotic activity at 10 µM. Molecular mechanisms of hits were explored in anesthetic-sensitive ion channels using electrophysiology, or in zebrafish using a specific reversal agent. RESULTS Zebrafish larvae assays required far less drug, time, and effort than tadpoles. In validation experiments, zebrafish and tadpole screening for hypnotic activity agreed 100% (n = 11; P = 0.002), and potencies were very similar (Pearson correlation, r > 0.999). Two reversible and potent sedative-hypnotics were discovered in the library subset. CMLD003237 (EC50, ~11 µM) weakly modulated γ-aminobutyric acid type A receptors and inhibited neuronal nicotinic receptors. CMLD006025 (EC50, ~13 µM) inhibited both N-methyl-D-aspartate and neuronal nicotinic receptors. CONCLUSIONS Photomotor response assays in zebrafish larvae are a mechanism-independent platform for high-throughput screening to identify novel sedative-hypnotics. The variety of chemotypes producing hypnosis is likely much larger than currently known.
Collapse
|
4
|
Wu B, Jayakar SS, Zhou X, Titterton K, Chiara DC, Szabo AL, Savechenkov PY, Kent DE, Cohen JB, Forman SA, Miller KW, Bruzik KS. Inhibitable photolabeling by neurosteroid diazirine analog in the β3-Subunit of human hetereopentameric type A GABA receptors. Eur J Med Chem 2018; 162:810-824. [PMID: 30544077 DOI: 10.1016/j.ejmech.2018.11.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 11/06/2018] [Accepted: 11/08/2018] [Indexed: 12/22/2022]
Abstract
Pregnanolone and allopregnanolone-type ligands exert general anesthetic, anticonvulsant and anxiolytic effects due to their positive modulatory interactions with the GABAA receptors in the brain. Binding sites for these neurosteroids have been recently identified at subunit interfaces in the transmembrane domain (TMD) of homomeric β3 GABAA receptors using photoaffinity labeling techniques, and in homomeric chimeric receptors containing GABAA receptor α subunit TMDs by crystallography. Steroid binding sites have yet to be determined in human, heteromeric, functionally reconstituted, full-length, glycosylated GABAA receptors. Here, we report on the synthesis and pharmacological characterization of several photoaffinity analogs of pregnanolone and allopregnanolone, of which 21-[4-(3-(trifluoromethyl)-3H-diazirin-3-yl)benzoxy]allopregnanolone (21-pTFDBzox-AP) was the most potent ligand. It is a partial positive modulator of the human α1β3 and α1β3γ2L GABAA receptors at sub-micromolar concentrations. [3H]21-pTFDBzox-AP photoincorporated in a pharmacologically specific manner into the α and β subunits of those receptors, with the β3 subunit photolabeled most efficiently. Importantly, photolabeling by [3H]21-pTFDBzox-AP was inhibited by the positive steroid modulators alphaxalone, pregnanolone and allopregnanolone, but not by inhibitory neurosteroid pregnenolone sulfate or by two potent general anesthetics and GABAAR positive allosteric modulators, etomidate and an anesthetic barbiturate. The latter two ligands bind to sites at subunit interfaces in the GABAAR that are different from those interacting with neurosteroids. 21-pTFDBzox-AP's potency and pharmacological specificity of photolabeling indicate its suitability for characterizing neurosteroid binding sites in native GABAA receptors.
Collapse
Affiliation(s)
- Bo Wu
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 South Wood Street, Chicago, IL, 60612, USA
| | - Selwyn S Jayakar
- Department of Neurobiology, 220 Longwood Avenue, Harvard Medical School, Boston, MA, 02115, USA
| | - Xiaojuan Zhou
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, 32 Fruit Street, Boston, MA, 02114, USA
| | - Katherine Titterton
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, 32 Fruit Street, Boston, MA, 02114, USA
| | - David C Chiara
- Department of Neurobiology, 220 Longwood Avenue, Harvard Medical School, Boston, MA, 02115, USA
| | - Andrea L Szabo
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, 32 Fruit Street, Boston, MA, 02114, USA
| | - Pavel Y Savechenkov
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 South Wood Street, Chicago, IL, 60612, USA
| | - Daniel E Kent
- Department of Health Science, Northeastern University, 360 Huntington Ave, Boston, MA, 02115, USA
| | - Jonathan B Cohen
- Department of Neurobiology, 220 Longwood Avenue, Harvard Medical School, Boston, MA, 02115, USA
| | - Stuart A Forman
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, 32 Fruit Street, Boston, MA, 02114, USA
| | - Keith W Miller
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, 32 Fruit Street, Boston, MA, 02114, USA; Department of Biological Chemistry and Molecular Pharmacology, 220 Longwood Avenue, Harvard Medical School, Boston, MA, 02115, USA
| | - Karol S Bruzik
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 South Wood Street, Chicago, IL, 60612, USA.
| |
Collapse
|
5
|
Structural basis of neurosteroid anesthetic action on GABA A receptors. Nat Commun 2018; 9:3972. [PMID: 30266951 PMCID: PMC6162318 DOI: 10.1038/s41467-018-06361-4] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 08/28/2018] [Indexed: 12/05/2022] Open
Abstract
Type A γ-aminobutyric acid receptors (GABAARs) are inhibitory pentameric ligand-gated ion channels in the brain. Many anesthetics and neurosteroids act through binding to the GABAAR transmembrane domain (TMD), but the structural basis of their actions is not well understood and no resting-state GABAAR structure has been determined. Here, we report crystal structures of apo and the neurosteroid anesthetic alphaxalone-bound desensitized chimeric α1GABAAR (ELIC-α1GABAAR). The chimera retains the functional and pharmacological properties of GABAARs, including potentiation, activation and desensitization by alphaxalone. The apo-state structure reveals an unconventional activation gate at the intracellular end of the pore. The desensitized structure illustrates molecular determinants for alphaxalone binding to an inter-subunit TMD site. These structures suggest a plausible signaling pathway from alphaxalone binding at the bottom of the TMD to the channel gate in the pore-lining TM2 through the TM1–TM2 linker. The study provides a framework to discover new GABAAR modulators with therapeutic potential. The anesthetic alphaxalone binds γ-aminobutyric acid type A receptors (GABAARs) that play an important role in regulating sensory processes. Here the authors present the structures of a α1GABAAR chimera in the resting state and in an alphaxalone-bound desensitized state, which might facilitate the development of new GABAAR modulators.
Collapse
|
6
|
Alphaxalone Binds in Inner Transmembrane β+-α- Interfaces of α1β3γ2 γ-Aminobutyric Acid Type A Receptors. Anesthesiology 2018; 128:338-351. [PMID: 29210709 DOI: 10.1097/aln.0000000000001978] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
BACKGROUND Neurosteroids like alphaxalone are potent anxiolytics, anticonvulsants, amnestics, and sedative-hypnotics, with effects linked to enhancement of γ-aminobutyric acid type A (GABAA) receptor gating in the central nervous system. Data locating neurosteroid binding sites on synaptic αβγ GABAA receptors are sparse and inconsistent. Some evidence points to outer transmembrane β-α interfacial pockets, near sites that bind the anesthetics etomidate and propofol. Other evidence suggests that steroids bind more intracellularly in β-α interfaces. METHODS The authors created 12 single-residue β3 cysteine mutations: β3T262C and β3T266C in β3-M2; and β3M283C, β3Y284C, β3M286C, β3G287C, β3F289C, β3V290C, β3F293C, β3L297C, β3E298C, and β3F301C in β3-M3 helices. The authors coexpressed α1 and γ2L with each mutant β3 subunit in Xenopus oocytes and electrophysiologically tested each mutant for covalent sulfhydryl modification by the water-soluble reagent para-chloromercuribenzenesulfonate. Then, the authors assessed whether receptor-bound alphaxalone, etomidate, or propofol blocked cysteine modification, implying steric hindrance. RESULTS Eleven mutant β3 subunits, when coexpressed with α1 and γ2L, formed functional channels that displayed varied sensitivities to the three anesthetics. Exposure to para-chloromercuribenzenesulfonate produced irreversible functional changes in ten mutant receptors. Protection by alphaxalone was observed in receptors with β3V290C, β3F293C, β3L297C, or β3F301C mutations. Both etomidate and propofol protected receptors with β3M286C or β3V290C mutations. Etomidate also protected β3F289C. In α1β3γ2L structural homology models, all these protected residues are located in transmembrane β-α interfaces. CONCLUSIONS Alphaxalone binds in transmembrane β-α pockets of synaptic GABAA receptors that are adjacent and intracellular to sites for the potent anesthetics etomidate and propofol.
Collapse
|
7
|
Kou KGM, Kulyk S, Marth CJ, Lee JC, Doering NA, Li BX, Gallego GM, Lebold TP, Sarpong R. A Unifying Synthesis Approach to the C 18-, C 19-, and C 20-Diterpenoid Alkaloids. J Am Chem Soc 2017; 139:13882-13896. [PMID: 28858498 PMCID: PMC6372304 DOI: 10.1021/jacs.7b07706] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The secondary metabolites that comprise the diterpenoid alkaloids are categorized into C18, C19, and C20 families depending on the number of contiguous carbon atoms that constitute their central framework. Herein, we detail our efforts to prepare these molecules by chemical synthesis, including a photochemical approach, and ultimately a bioinspired strategy that has resulted in the development of a unifying synthesis of one C18 (weisaconitine D), one C19 (liljestrandinine), and three C20 (cochlearenine, paniculamine, and N-ethyl-1α-hydroxy-17-veratroyldictyzine) natural products from a common intermediate.
Collapse
Affiliation(s)
- Kevin G. M. Kou
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | | | | | | | - Nicolle A. Doering
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Beryl X. Li
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | | | | | - Richmond Sarpong
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| |
Collapse
|
8
|
Tryptophan and Cysteine Mutations in M1 Helices of α1β3γ2L γ-Aminobutyric Acid Type A Receptors Indicate Distinct Intersubunit Sites for Four Intravenous Anesthetics and One Orphan Site. Anesthesiology 2017; 125:1144-1158. [PMID: 27753644 DOI: 10.1097/aln.0000000000001390] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND γ-Aminobutyric acid type A (GABAA) receptors mediate important effects of intravenous general anesthetics. Photolabel derivatives of etomidate, propofol, barbiturates, and a neurosteroid get incorporated in GABAA receptor transmembrane helices M1 and M3 adjacent to intersubunit pockets. However, photolabels have not been consistently targeted at heteromeric αβγ receptors and do not form adducts with all contact residues. Complementary approaches may further define anesthetic sites in typical GABAA receptors. METHODS Two mutation-based strategies, substituted tryptophan sensitivity and substituted cysteine modification-protection, combined with voltage-clamp electrophysiology in Xenopus oocytes, were used to evaluate interactions between four intravenous anesthetics and six amino acids in M1 helices of α1, β3, and γ2L GABAA receptor subunits: two photolabeled residues, α1M236 and β3M227, and their homologs. RESULTS Tryptophan substitutions at α1M236 and positional homologs β3L231 and γ2L246 all caused spontaneous channel gating and reduced γ-aminobutyric acid EC50. Substituted cysteine modification experiments indicated etomidate protection at α1L232C and α1M236C, R-5-allyl-1-methyl-5-(m-trifluoromethyl-diazirinylphenyl) barbituric acid protection at β3M227C and β3L231C, and propofol protection at α1M236C and β3M227C. No alphaxalone protection was evident at the residues the authors explored, and none of the tested anesthetics protected γ2I242C or γ2L246C. CONCLUSIONS All five intersubunit transmembrane pockets of GABAA receptors display similar allosteric linkage to ion channel gating. Substituted cysteine modification and protection results were fully concordant with anesthetic photolabeling at α1M236 and β3M227 and revealed overlapping noncongruent sites for etomidate and propofol in β-α interfaces and R-5-allyl-1-methyl-5-(m-trifluoromethyl-diazirinylphenyl) barbituric acid and propofol in α-β and γ-β interfaces. The authors' results identify the α-γ transmembrane interface as a potentially unique orphan modulator site.
Collapse
|
9
|
Savechenkov PY, Chiara DC, Desai R, Stern AT, Zhou X, Ziemba AM, Szabo AL, Zhang Y, Cohen JB, Forman SA, Miller KW, Bruzik KS. Synthesis and pharmacological evaluation of neurosteroid photoaffinity ligands. Eur J Med Chem 2017; 136:334-347. [PMID: 28505538 DOI: 10.1016/j.ejmech.2017.04.043] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 04/17/2017] [Accepted: 04/18/2017] [Indexed: 10/19/2022]
Abstract
Neuroactive steroids are potent positive allosteric modulators of GABAA receptors (GABAAR), but the locations of their GABAAR binding sites remain poorly defined. To discover these sites, we synthesized two photoreactive analogs of alphaxalone, an anesthetic neurosteroid targeting GABAAR, 11β-(4-azido-2,3,5,6-tetrafluorobenzoyloxy)allopregnanolone, (F4N3Bzoxy-AP) and 11-aziallopregnanolone (11-AziAP). Both photoprobes acted with equal or higher potency than alphaxalone as general anesthetics and potentiators of GABAAR responses, left-shifting the GABA concentration - response curve for human α1β3γ2 GABAARs expressed in Xenopus oocytes, and enhancing [3H]muscimol binding to α1β3γ2 GABAARs expressed in HEK293 cells. With EC50 of 110 nM, 11-AziAP is one the most potent general anesthetics reported. [3H]F4N3Bzoxy-AP and [3H]11-AziAP, at anesthetic concentrations, photoincorporated into α- and β-subunits of purified α1β3γ2 GABAARs, but labeling at the subunit level was not inhibited by alphaxalone (30 μM). The enhancement of photolabeling by 3H-azietomidate and 3H-mTFD-MPAB in the presence of either of the two steroid photoprobes indicates the neurosteroid binding site is different from, but allosterically related to, the etomidate and barbiturate sites. Our observations are consistent with two hypotheses. First, F4N3Bzoxy-AP and 11-aziAP bind to a high affinity site in such a pose that the 11-photoactivatable moiety, that is rigidly attached to the steroid backbone, points away from the protein. Second, F4N3Bzoxy-AP, 11-aziAP and other steroid anesthetics, which are present at very high concentration at the lipid-protein interface due to their high lipophilicity, act via low affinity sites, as proposed by Akk et al. (Psychoneuroendocrinology2009, 34S1, S59-S66).
Collapse
Affiliation(s)
- Pavel Y Savechenkov
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 South Wood Street (M/C 781), Chicago, IL 60612-7231, USA
| | - David C Chiara
- Department of Neurobiology, 220 Longwood Avenue, Harvard Medical School, Boston, MA 02115, USA
| | - Rooma Desai
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, 32 Fruit Street, Boston, MA 02114, USA
| | - Alexander T Stern
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, 32 Fruit Street, Boston, MA 02114, USA
| | - Xiaojuan Zhou
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, 32 Fruit Street, Boston, MA 02114, USA
| | - Alexis M Ziemba
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, 32 Fruit Street, Boston, MA 02114, USA
| | - Andrea L Szabo
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, 32 Fruit Street, Boston, MA 02114, USA
| | - Yinghui Zhang
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, 32 Fruit Street, Boston, MA 02114, USA
| | - Jonathan B Cohen
- Department of Neurobiology, 220 Longwood Avenue, Harvard Medical School, Boston, MA 02115, USA
| | - Stuart A Forman
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, 32 Fruit Street, Boston, MA 02114, USA
| | - Keith W Miller
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, 32 Fruit Street, Boston, MA 02114, USA; Department of Biological Chemistry and Molecular Pharmacology, 220 Longwood Avenue, Harvard Medical School, Boston, MA 02115, USA
| | - Karol S Bruzik
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 South Wood Street (M/C 781), Chicago, IL 60612-7231, USA.
| |
Collapse
|
10
|
Marth CJ, Gallego GM, Lee JC, Lebold TP, Kulyk S, Kou KGM, Qin J, Lilien R, Sarpong R. Network-analysis-guided synthesis of weisaconitine D and liljestrandinine. Nature 2015; 528:493-8. [PMID: 26675722 PMCID: PMC4688071 DOI: 10.1038/nature16440] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 10/30/2015] [Indexed: 11/24/2022]
Abstract
General strategies for the chemical synthesis of organic compounds, especially of architecturally complex natural products, are not easily identified. Here we present a method to establish a strategy for such syntheses, which uses network analysis. This approach has led to the identification of a versatile synthetic intermediate that facilitated syntheses of the diterpenoid alkaloids weisaconitine D and liljestrandinine, and the core of gomandonine. We also developed a web-based graphing program that allows network analysis to be easily performed on molecules with complex frameworks. The diterpenoid alkaloids comprise some of the most architecturally complex and functional-group-dense secondary metabolites isolated. Consequently, they present a substantial challenge for chemical synthesis. The synthesis approach described here is a notable departure from other single-target-focused strategies adopted for the syntheses of related structures. Specifically, it affords not only the targeted natural products, but also intermediates and derivatives in the three families of diterpenoid alkaloids (C-18, C-19 and C-20), and so provides a unified synthetic strategy for these natural products. This work validates the utility of network analysis as a starting point for identifying strategies for the syntheses of architecturally complex secondary metabolites.
Collapse
Affiliation(s)
- C. J. Marth
- Department of Chemistry. University of California, Berkeley, CA 94720, United States
| | - G. M. Gallego
- Department of Chemistry. University of California, Berkeley, CA 94720, United States
| | - J. C. Lee
- Department of Chemistry. University of California, Berkeley, CA 94720, United States
| | - T. P. Lebold
- Department of Chemistry. University of California, Berkeley, CA 94720, United States
| | - S. Kulyk
- Department of Chemistry. University of California, Berkeley, CA 94720, United States
| | - K. G. M. Kou
- Department of Chemistry. University of California, Berkeley, CA 94720, United States
| | - J. Qin
- Cadre Research Labs, Chicago, IL 60654, United States
| | - R. Lilien
- Cadre Research Labs, Chicago, IL 60654, United States
| | - R. Sarpong
- Department of Chemistry. University of California, Berkeley, CA 94720, United States
| |
Collapse
|
11
|
Qian M, Krishnan K, Kudova E, Li P, Manion BD, Taylor A, Elias G, Akk G, Evers AS, Zorumski CF, Mennerick S, Covey DF. Neurosteroid analogues. 18. Structure-activity studies of ent-steroid potentiators of γ-aminobutyric acid type A receptors and comparison of their activities with those of alphaxalone and allopregnanolone. J Med Chem 2014; 57:171-90. [PMID: 24328079 PMCID: PMC3951241 DOI: 10.1021/jm401577c] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A model of the alignment of neurosteroids and ent-neurosteroids at the same binding site on γ-aminobutyric acid type A (GABAA) receptors was evaluated for its ability to identify the structural features in ent-neurosteroids that enhance their activity as positive allosteric modulators of this receptor. Structural features that were identified included: (1) a ketone group at position C-16, (2) an axial 4α-OMe group, and (3) a C-18 methyl group. Two ent-steroids were identified that were more potent than the anesthetic steroid alphaxalone in their threshold for and duration of loss of the righting reflex in mice. In tadpoles, loss of righting reflex for these two ent-steroids occurs with EC50 values similar to those found for allopregnanolone. The results indicate that ent-steroids have considerable potential to be developed as anesthetic agents and as drugs to treat brain disorders that are ameliorated by positive allosteric modulators of GABAA receptor function.
Collapse
Affiliation(s)
- Mingxing Qian
- Department of Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
| | - Kathiresan Krishnan
- Department of Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
| | - Eva Kudova
- Department of Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
- Department of Anesthesiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
| | - Ping Li
- Department of Anesthesiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
| | - Brad D. Manion
- Department of Anesthesiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
| | - Amanda Taylor
- Department of Psychiatry, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
| | | | - Gustav Akk
- Department of Anesthesiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
- Department of Radiology, The Taylor Family Institute for Innovative Psychiatric Research, Washington University in St. Louis, St. Louis, Missouri, 63110, United States
| | - Alex S. Evers
- Department of Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
- Department of Anesthesiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
- Department of Radiology, The Taylor Family Institute for Innovative Psychiatric Research, Washington University in St. Louis, St. Louis, Missouri, 63110, United States
| | - Charles F. Zorumski
- Department of Psychiatry, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
- Department of Radiology, The Taylor Family Institute for Innovative Psychiatric Research, Washington University in St. Louis, St. Louis, Missouri, 63110, United States
- Department of Anatomy and Neurobiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
| | - Steven Mennerick
- Department of Psychiatry, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
- Department of Radiology, The Taylor Family Institute for Innovative Psychiatric Research, Washington University in St. Louis, St. Louis, Missouri, 63110, United States
- Department of Anatomy and Neurobiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
| | - Douglas F. Covey
- Department of Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
- Department of Anesthesiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
- Department of Psychiatry, Washington University in St. Louis School of Medicine, St. Louis, Missouri, 63110, United States
- Department of Radiology, The Taylor Family Institute for Innovative Psychiatric Research, Washington University in St. Louis, St. Louis, Missouri, 63110, United States
| |
Collapse
|
12
|
Slavíková B, Bujons J, Matyáš L, Vidal M, Babot Z, Krištofíková Z, Suñol C, Kasal A. Allopregnanolone and pregnanolone analogues modified in the C ring: synthesis and activity. J Med Chem 2013; 56:2323-36. [PMID: 23421641 DOI: 10.1021/jm3016365] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
(25R)-3β-Hydroxy-5α-spirostan-12-one (hecogenin) and 11α-hydroxypregn-4-ene-3,20-dione (11α-hydroxyprogesterone) were used as starting materials for the synthesis of a series of 11- and 12-substituted derivatives of 5ξ-pregnanolone (3α-hydroxy-5α-pregnan-20-one and 3α-hydroxy-5β-pregnan-20-one), the principal neurosteroid acting via γ-aminobutyric acid (GABA). These analogues were designed to study the structural requirements of the corresponding GABAA receptor. Their biological activity was measured by in vitro test with [(3)H]flunitrazepam as radioligand in which allopregnanolone and its active analogues stimulated the binding to the GABAA receptor. Analysis of the SAR data suggests dependence of the flunitrazepam binding activity on the hydrophobic-hydrophilic balance of the groups at the C-ring edge rather than on specific interactions between them and the receptor.
Collapse
Affiliation(s)
- Barbora Slavíková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 166 10 Prague 6, Czech Republic
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Stastna E, Krishnan K, Manion BD, Taylor A, Rath NP, Chen ZW, Evers AS, Zorumski CF, Mennerick S, Covey DF. Neurosteroid analogues. 16. A new explanation for the lack of anesthetic effects of δ(16)-alphaxalone and identification of a δ(17(20)) analogue with potent anesthetic activity. J Med Chem 2011; 54:3926-34. [PMID: 21504158 PMCID: PMC3794474 DOI: 10.1021/jm2002487] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This study addresses the hypothesis that the lack of anesthetic activity for (3α,5α)-3-hydroxypregn-16-ene-11,20-dione (Δ(16)-alphaxalone) is explained by the steroid Δ(16) double bond constraining the steroid 20-carbonyl group to a position that prevents it from favorably interacting with γ-aminobutyric acid type A (GABA(A)) receptors. A series of Δ(16) and Δ(17(20)) analogues of Δ(16)-alphaxalone was prepared to evaluate this hypothesis in binding, electrophysiological, and tadpole anesthesia experiments. The results obtained failed to support the hypothesis. Instead, the results indicate that it is the presence of the C-21 methyl group in Δ(16)-alphaxalone, not the location of the constrained C-20 carbonyl group, that prevents Δ(16)-alphaxalone from interacting strongly with the GABA(A) receptor and having anesthetic activity. Consistent with this conclusion, a Δ(17(20)) analogue of Δ(16)-alphaxalone without a C-21 methyl group was found to be very similar to the anesthetic steroid (3α,5α)-3-hydroxypregnane-11,20-dione (alphaxalone) with regard to time of onset and rate of recovery from anesthesia when administered to mice by tail vein injection.
Collapse
Affiliation(s)
- Eva Stastna
- Department of Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, Missouri 63110
| | - Kathiresan Krishnan
- Department of Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, Missouri 63110
| | - Brad D. Manion
- Department of Anesthesiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri 63110
| | - Amanda Taylor
- Department of Psychiatry, Washington University in St. Louis School of Medicine, St. Louis, Missouri 63110
| | - Nigam P. Rath
- Department of Chemistry and Biochemistry, University of Missouri–St. Louis, St. Louis, Missouri 63121
| | - Zi-Wei Chen
- Department of Anesthesiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri 63110
| | - Alex. S. Evers
- Department of Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, Missouri 63110
- Department of Anesthesiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri 63110
| | - Charles F. Zorumski
- Department of Psychiatry, Washington University in St. Louis School of Medicine, St. Louis, Missouri 63110
- Department of Anatomy and Neurobiology Washington University in St. Louis School of Medicine, St. Louis, Missouri 63110
| | - Steven Mennerick
- Department of Psychiatry, Washington University in St. Louis School of Medicine, St. Louis, Missouri 63110
- Department of Anatomy and Neurobiology Washington University in St. Louis School of Medicine, St. Louis, Missouri 63110
| | - Douglas F. Covey
- Department of Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, Missouri 63110
| |
Collapse
|