1
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Villalba DR, Jannu AK, Javed E, Dandekar I, Wang R, Deshpande DA, An SS, Panettieri RA, Tang DD, Penn RB, Nayak AP. Ovarian Cancer G protein-coupled receptor-1 signaling bias dictates anti-contractile effect of benzodiazepines on airway smooth muscle. Respir Res 2025; 26:183. [PMID: 40361189 PMCID: PMC12076885 DOI: 10.1186/s12931-025-03268-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2025] [Accepted: 05/05/2025] [Indexed: 05/15/2025] Open
Abstract
BACKGROUND We recently reported that the ovarian cancer G protein-coupled receptor-1 (OGR1) can be pharmacologically biased with specific benzodiazepines to couple with distinct heterotrimeric G proteins in human airway smooth muscle (ASM) cells. Lorazepam stimulated both Gs and Gq signaling via OGR1, whereas sulazepam only stimulated Gs signaling in ASM cells. The present study sought to determine the effects of sulazepam and lorazepam on contraction of human precision cut lung slices (hPCLS), and detail the biochemical mechanisms mediating these effects. METHODS Models of histamine (His) -stimulated contraction included imaging of ex vivo human precision cut lung slices (hPCLS) and Magnetic Twisting Cytometry (MTC) analysis of human ASM cell stiffness. To explore mechanisms of regulation, we examined effects on myosin light chain (pMLC) phosphorylation and PKA activity in primary human ASM cultures, as well as actin cytoskeleton integrity as defined by changes in the ratio of F to G actin assessed by immunofluorescence. RESULTS In a dose-dependent manner, sulazepam relaxed His-contracted hPCLS and reduced baseline cell stiffness. Lorazepam did not relax His-contracted hPCLS, and only at a maximal dose (100 μM) did lorazepam relax baseline cell stiffness. The Gs-biased ligand sulazepam stimulated PKA activity as evidenced by significant induction of VASP and HSP20 phosphorylation, which was associated with significant inhibition of His-induced pMLC phosphorylation. Conversely, the balanced ligand lorazepam did not significantly increase HSP20 phosphorylation or VASP phosphorylation and did not significantly inhibit His-induced MLC phosphorylation. Sulazepam was also able to inhibit histamine induced F-actin formation. CONCLUSIONS The Gs-biased OGR1 ligand sulazepam relaxed contracted ASM in both tissue- and cell- based models, via inhibition of MLC phosphorylation in a PKA-dependent manner and through inhibition of actin stress fiber formation. The relative inability of the balanced ligand lorazepam to influence ASM contractile state was likely due to competitive actions of concomitant Gq and Gs signaling.
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Affiliation(s)
- Dominic R Villalba
- Department of Medicine, Center for Translational Medicine & Division of Pulmonary and Critical Care Medicine; Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Arun K Jannu
- Department of Medicine, Center for Translational Medicine & Division of Pulmonary and Critical Care Medicine; Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Elham Javed
- Department of Medicine, Center for Translational Medicine & Division of Pulmonary and Critical Care Medicine; Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | | | - Ruping Wang
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY, USA
| | - Deepak A Deshpande
- Department of Medicine, Center for Translational Medicine & Division of Pulmonary and Critical Care Medicine; Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | | | | | - Dale D Tang
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY, USA
| | - Raymond B Penn
- Department of Medicine, Center for Translational Medicine & Division of Pulmonary and Critical Care Medicine; Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Ajay P Nayak
- Department of Medicine, Center for Translational Medicine & Division of Pulmonary and Critical Care Medicine; Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA.
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2
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Gajić Bojić M, Aranđelović J, Škrbić R, Savić MM. Peripheral GABA A receptors - Physiological relevance and therapeutic implications. Pharmacol Ther 2025; 266:108759. [PMID: 39615599 DOI: 10.1016/j.pharmthera.2024.108759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2024] [Revised: 11/04/2024] [Accepted: 11/22/2024] [Indexed: 12/13/2024]
Abstract
The role of γ- aminobutyric acid (GABA) and GABAA receptors is not only essential for neurotransmission in the central nervous system (CNS), but they are also involved in communication in various peripheral tissues such as the pancreas, liver, kidney, gastrointestinal tract, trachea, immune cells and blood vessels. GABAA receptors located outside the CNS ("peripheral GABAA receptors") enable both neuronal and non-neuronal GABA-ergic signaling in various physiological processes and are generally thought to have similar properties to the extrasynaptic receptors in the CNS. By activating these peripheral receptors, GABA and various GABAA receptor modulators, including drugs such as benzodiazepines and general anesthetics, may contribute to or otherwise affect the maintenance of general body homeostasis. However, the existing data in the literature on the role of non-neuronal GABA-ergic signaling in insulin secretion, glucose metabolism, renal function, intestinal motility, airway tone, immune response and blood pressure regulation are far from complete. In fact, they mainly focus on the identification of components for the local synthesis and utilization of GABA and on the expression repertoire of GABAA receptor subunits rather than on subunit composition, activation effects and (sub)cellular localization. A deeper understanding of how modulation of peripheral GABAA receptors can have significant therapeutic effects on a range of pathological conditions such as multiple sclerosis, diabetes, irritable bowel syndrome, asthma or hypertension could contribute to the development of more specific pharmacological strategies that would provide an alternative or complement to existing therapies. Selective GABAA receptor modulators with improved peripheral efficacy and reduced central side effects would therefore be highly desirable first-in-class drug candidates. This review updates recent advances unraveling the molecular components and cellular determinants of the GABA signaling machinery in peripheral organs, tissues and cells of both, humans and experimental animals.
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Affiliation(s)
- Milica Gajić Bojić
- Faculty of Medicine, Center for Biomedical Research, University of Banja Luka, Banja Luka 78000, Republic of Srpska, Bosnia and Herzegovina; Department of Pharmacology, Toxicology and Clinical Pharmacology, University of Banja Luka - Faculty of Medicine, Banja Luka 78000, Republic of Srpska, Bosnia and Herzegovina
| | - Jovana Aranđelović
- Department of Pharmacology, University of Belgrade - Faculty of Pharmacy, Belgrade 11000, Serbia
| | - Ranko Škrbić
- Faculty of Medicine, Center for Biomedical Research, University of Banja Luka, Banja Luka 78000, Republic of Srpska, Bosnia and Herzegovina; Department of Pharmacology, Toxicology and Clinical Pharmacology, University of Banja Luka - Faculty of Medicine, Banja Luka 78000, Republic of Srpska, Bosnia and Herzegovina
| | - Miroslav M Savić
- Department of Pharmacology, University of Belgrade - Faculty of Pharmacy, Belgrade 11000, Serbia.
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3
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Wildman SS, Dunn K, Van Beusecum JP, Inscho EW, Kelley S, Lilley RJ, Cook AK, Taylor KD, Peppiatt-Wildman CM. A novel functional role for the classic CNS neurotransmitters, GABA, glycine, and glutamate, in the kidney: potent and opposing regulators of the renal vasculature. Am J Physiol Renal Physiol 2023; 325:F38-F49. [PMID: 37102686 PMCID: PMC10511176 DOI: 10.1152/ajprenal.00425.2021] [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: 12/01/2021] [Revised: 03/29/2023] [Accepted: 04/22/2023] [Indexed: 04/28/2023] Open
Abstract
The presence of a renal GABA/glutamate system has previously been described; however, its functional significance in the kidney remains undefined. We hypothesized, given its extensive presence in the kidney, that activation of this GABA/glutamate system would elicit a vasoactive response from the renal microvessels. The functional data here demonstrate, for the first time, that activation of endogenous GABA and glutamate receptors in the kidney significantly alters microvessel diameter with important implications for influencing renal blood flow. Renal blood flow is regulated in both the renal cortical and medullary microcirculatory beds via diverse signaling pathways. GABA- and glutamate-mediated effects on renal capillaries are strikingly similar to those central to the regulation of central nervous system capillaries, that is, exposing renal tissue to physiological concentrations of GABA, glutamate, and glycine led to alterations in the way that contractile cells, pericytes, and smooth muscle cells, regulate microvessel diameter in the kidney. Since dysregulated renal blood flow is linked to chronic renal disease, alterations in the renal GABA/glutamate system, possibly through prescription drugs, could significantly impact long-term kidney function.NEW & NOTEWORTHY Functional data here offer novel insight into the vasoactive activity of the renal GABA/glutamate system. These data show that activation of endogenous GABA and glutamate receptors in the kidney significantly alters microvessel diameter. Furthermore, the results show that these antiepileptic drugs are as potentially challenging to the kidney as nonsteroidal anti-inflammatory drugs.
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Affiliation(s)
| | - Kadeshia Dunn
- Division of Natural Sciences, University of Kent, Kent, United Kingdom
| | - Justin P Van Beusecum
- Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina, United States
- Medical University of South Carolina, Charleston, South Carolina, United States
| | - Edward W Inscho
- Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Stephen Kelley
- Division of Natural Sciences, University of Kent, Kent, United Kingdom
| | - Rebecca J Lilley
- Division of Natural Sciences, University of Kent, Kent, United Kingdom
| | - Anthony K Cook
- Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Kirsti D Taylor
- Division of Natural Sciences, University of Kent, Kent, United Kingdom
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4
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Nayak AP, An SS. Anxiolytics for Bronchodilation: Refinements to GABA A Agonists for Asthma Relief. Am J Respir Cell Mol Biol 2022; 67:419-420. [PMID: 35901197 PMCID: PMC9564927 DOI: 10.1165/rcmb.2022-0287ed] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- Ajay P Nayak
- Center for Translational Medicine
- Department of Medicine Thomas Jefferson University Philadelphia, Pennsylvania
| | - Steven S An
- Rutgers Institute for Translational Medicine and Science New Brunswick, New Jersey
- Rutgers-Robert Wood Johnson Medical School The State University of New Jersey Piscataway, New Jersey
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5
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Perez-Zoghbi JF, Sajorda DR, Webb DA, Arnold LA, Emala CW, Yocum GT. Imidazobenzodiazepine PI320 Relaxes Mouse Peripheral Airways by Inhibiting Calcium Mobilization. Am J Respir Cell Mol Biol 2022; 67:482-490. [PMID: 35776523 PMCID: PMC9564932 DOI: 10.1165/rcmb.2022-0084oc] [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: 02/28/2022] [Accepted: 07/01/2022] [Indexed: 02/06/2023] Open
Abstract
Asthma is a common respiratory disease characterized, in part, by excessive airway smooth muscle (ASM) contraction (airway hyperresponsiveness). Various GABAAR (γ-aminobutyric acid type A receptor) activators, including benzodiazepines, relax ASM. The GABAAR is a ligand-operated Cl- channel best known for its role in inhibitory neurotransmission in the central nervous system. Although ASM cells express GABAARs, affording a seemingly logical site of action, the mechanism(s) by which GABAAR ligands relax ASM remains unclear. PI320, a novel imidazobenzodiazepine designed for tissue selectivity, is a promising asthma drug candidate. Here, we show that PI320 alleviates methacholine (MCh)-induced bronchoconstriction in vivo and relaxes peripheral airways preconstricted with MCh ex vivo using the forced oscillation technique and precision-cut lung slice experiments, respectively. Surprisingly, the peripheral airway relaxation demonstrated in precision-cut lung slices does not appear to be GABAAR-dependent, as it is not inhibited by the GABAAR antagonist picrotoxin or the benzodiazepine antagonist flumazenil. Furthermore, we demonstrate here that PI320 inhibits MCh-induced airway constriction in the absence of external Ca2, suggesting that PI320-mediated relaxation is not mediated by inhibition of Ca2+ influx in ASM. However, PI320 does inhibit MCh-induced intracellular Ca2+ oscillations in peripheral ASM, a key mediator of contraction that is dependent on sarcoplasmic reticulum Ca2+ mobilization. Furthermore, PI320 inhibits peripheral airway constriction induced by experimentally increasing the intracellular concentration of inositol triphosphate (IP3). These novel data suggest that PI320 relaxes murine peripheral airways by inhibiting intracellular Ca2+ mobilization in ASM, likely by inhibiting Ca2+ release through IP3Rs (IP3 receptors).
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Affiliation(s)
- Jose F. Perez-Zoghbi
- Department of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York; and
| | - Dannah Rae Sajorda
- Department of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York; and
| | - Daniel A. Webb
- Department of Chemistry and Biochemistry and
- Milwaukee Institute for Drug Discovery, University of Wisconsin–Milwaukee, Milwaukee, Wisconsin
| | - Leggy A. Arnold
- Department of Chemistry and Biochemistry and
- Milwaukee Institute for Drug Discovery, University of Wisconsin–Milwaukee, Milwaukee, Wisconsin
| | - Charles W. Emala
- Department of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York; and
| | - Gene T. Yocum
- Department of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York; and
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6
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Garifulina A, Friesacher T, Stadler M, Zangerl-Plessl EM, Ernst M, Stary-Weinzinger A, Willam A, Hering S. β subunits of GABA A receptors form proton-gated chloride channels: Insights into the molecular basis. Commun Biol 2022; 5:784. [PMID: 35922471 PMCID: PMC9349252 DOI: 10.1038/s42003-022-03720-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 07/14/2022] [Indexed: 11/17/2022] Open
Abstract
Gamma-aminobutyric acid type A receptors (GABAARs) are ligand gated channels mediating inhibition in the central nervous system. Here, we identify a so far undescribed function of β-subunit homomers as proton-gated anion channels. Mutation of a single H267A in β3 subunits completely abolishes channel activation by protons. In molecular dynamic simulations of the β3 crystal structure protonation of H267 increased the formation of hydrogen bonds between H267 and E270 of the adjacent subunit leading to a pore stabilising ring formation and accumulation of Cl- within the transmembrane pore. Conversion of these residues in proton insensitive ρ1 subunits transfers proton-dependent gating, thus highlighting the role of this interaction in proton sensitivity. Activation of chloride and bicarbonate currents at physiological pH changes (pH50 is in the range 6- 6.3) and kinetic studies suggest a physiological role in neuronal and non-neuronal tissues that express beta subunits, and thus as potential novel drug target.
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Affiliation(s)
- Aleksandra Garifulina
- Division of Pharmacology and Toxicology, Department of Pharmaceutical Sciences, University of Vienna, A-1090, Vienna, Austria.
| | - Theres Friesacher
- Division of Pharmacology and Toxicology, Department of Pharmaceutical Sciences, University of Vienna, A-1090, Vienna, Austria
| | - Marco Stadler
- Division of Pharmacology and Toxicology, Department of Pharmaceutical Sciences, University of Vienna, A-1090, Vienna, Austria
| | - Eva-Maria Zangerl-Plessl
- Division of Pharmacology and Toxicology, Department of Pharmaceutical Sciences, University of Vienna, A-1090, Vienna, Austria
| | - Margot Ernst
- Department of Pathobiology of the Nervous System, Medical University of Vienna, A-1090, Vienna, Austria
| | - Anna Stary-Weinzinger
- Division of Pharmacology and Toxicology, Department of Pharmaceutical Sciences, University of Vienna, A-1090, Vienna, Austria
| | - Anita Willam
- Division of Pharmacology and Toxicology, Department of Pharmaceutical Sciences, University of Vienna, A-1090, Vienna, Austria
- ChanPharm GmbH, Am Kanal 27, Top 2/3/5, 1110, Vienna, Austria
| | - Steffen Hering
- Division of Pharmacology and Toxicology, Department of Pharmaceutical Sciences, University of Vienna, A-1090, Vienna, Austria.
- ChanPharm GmbH, Am Kanal 27, Top 2/3/5, 1110, Vienna, Austria.
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7
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Cerne R, Lippa A, Poe MM, Smith JL, Jin X, Ping X, Golani LK, Cook JM, Witkin JM. GABAkines - Advances in the discovery, development, and commercialization of positive allosteric modulators of GABA A receptors. Pharmacol Ther 2022; 234:108035. [PMID: 34793859 PMCID: PMC9787737 DOI: 10.1016/j.pharmthera.2021.108035] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 11/08/2021] [Indexed: 12/25/2022]
Abstract
Positive allosteric modulators of γ-aminobutyric acid-A (GABAA) receptors or GABAkines have been widely used medicines for over 70 years for anxiety, epilepsy, sleep, and other disorders. Traditional GABAkines like diazepam have safety and tolerability concerns that include sedation, motor-impairment, respiratory depression, tolerance and dependence. Multiple GABAkines have entered clinical development but the issue of side-effects has not been fully solved. The compounds that are presently being developed and commercialized include several neuroactive steroids (an allopregnanolone formulation (brexanolone), an allopregnanolone prodrug (LYT-300), Sage-324, zuranolone, and ganaxolone), the α2/3-preferring GABAkine, KRM-II-81, and the α2/3/5-preferring GABAkine PF-06372865 (darigabat). The neuroactive steroids are in clinical development for post-partum depression, intractable epilepsy, tremor, status epilepticus, and genetic epilepsy disorders. Darigabat is in development for epilepsy and anxiety. The imidazodiazepine, KRM-II-81 is efficacious in animal models for the treatment of epilepsy and post-traumatic epilepsy, acute and chronic pain, as well as anxiety and depression. The efficacy of KRM-II-81 in models of pharmacoresistant epilepsy, preventing the development of seizure sensitization, and in brain tissue of intractable epileptic patients bodes well for improved therapeutics. Medicinal chemistry efforts are also ongoing to identify novel and improved GABAkines. The data document gaps in our understanding of the molecular pharmacology of GABAkines that drive differential pharmacological profiles, but emphasize advancements in the ability to successfully utilize GABAA receptor potentiation for therapeutic gain in neurology and psychiatry.
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Affiliation(s)
- Rok Cerne
- Laboratory of Antiepileptic Drug Discovery, Ascension St. Vincent, Indianapolis, IN USA,Faculty of Medicine, University of Ljubljana, Zaloška cesta 4, Ljubljana, Slovenia.,RespireRx Pharmaceuticals Inc, Glen Rock, NJ, USA,Department of Anatomy and Cell Biology, Indiana University/Purdue University, Indianapolis, IN, USA
| | - Arnold Lippa
- RespireRx Pharmaceuticals Inc, Glen Rock, NJ, USA
| | | | - Jodi L. Smith
- Laboratory of Antiepileptic Drug Discovery, Ascension St. Vincent, Indianapolis, IN USA
| | - Xiaoming Jin
- Department of Anatomy and Cell Biology, Indiana University/Purdue University, Indianapolis, IN, USA
| | - Xingjie Ping
- Department of Anatomy and Cell Biology, Indiana University/Purdue University, Indianapolis, IN, USA
| | - Lalit K. Golani
- Department of Chemistry and Biochemistry, Milwaukee Institute of Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - James M. Cook
- RespireRx Pharmaceuticals Inc, Glen Rock, NJ, USA,Department of Chemistry and Biochemistry, Milwaukee Institute of Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Jeffrey M. Witkin
- Laboratory of Antiepileptic Drug Discovery, Ascension St. Vincent, Indianapolis, IN USA,RespireRx Pharmaceuticals Inc, Glen Rock, NJ, USA,Department of Chemistry and Biochemistry, Milwaukee Institute of Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
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8
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Pera T, Loblundo C, Penn RB. Pharmacological Management of Asthma and COPD. COMPREHENSIVE PHARMACOLOGY 2022:762-802. [DOI: 10.1016/b978-0-12-820472-6.00095-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2025]
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9
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Simeone X, Koniuszewski F, Müllegger M, Smetka A, Steudle F, Puthenkalam R, Ernst M, Scholze P. A Benzodiazepine Ligand with Improved GABA A Receptor α5-Subunit Selectivity Driven by Interactions with Loop C. Mol Pharmacol 2021; 99:39-48. [PMID: 33268553 DOI: 10.1124/molpharm.120.000067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 10/20/2020] [Indexed: 01/30/2023] Open
Abstract
The family of GABAA receptors is an important drug target group in the treatment of sleep disorders, anxiety, epileptic seizures, and many others. The most frequent GABAA receptor subtype is composed of two α-, two β-, and one γ2-subunit, whereas the nature of the α-subunit critically determines the properties of the benzodiazepine binding site of those receptors. Nearly all of the clinically relevant drugs target all GABAA receptor subtypes equally. In the past years, however, drug development research has focused on studying α5-containing GABAA receptors. Beyond the central nervous system, α5-containing GABAA receptors in airway smooth muscles are considered as an emerging target for bronchial asthma. Here, we investigated a novel compound derived from the previously described imidazobenzodiazepine SH-053-2'F-R-CH3 (SH53d-ester). Although SH53d-ester is only moderately selective for α5-subunit-containing GABAA receptors, the derivative SH53d-acid shows superior (>40-fold) affinity selectivity and is a positive modulator. Using two-electrode voltage clamp electrophysiology in Xenopus laevis oocytes and radioligand displacement assays with human embryonic kidney 293 cells, we demonstrated that an acid group as substituent on the imidazobenzodiazepine scaffold leads to large improvements of functional and binding selectivity for α5β3γ2 over other αxβ3γ2 GABAA receptors. Atom level structural studies provide hypotheses for the improved affinity to this receptor subtype. Mutational analysis confirmed the hypotheses, indicating that loop C of the GABAA receptor α-subunit is the dominant molecular determinant of drug selectivity. Thus, we characterize a promising novel α5-subunit-selective drug candidate. SIGNIFICANCE STATEMENT: In the current study we present the detailed pharmacological characterization of a novel compound derived from the previously described imidazobenzodiazepine SH-053-2'F-R-CH3. We describe its superior (>40-fold) affinity selectivity for α5-containing GABAA receptors and show atom-level structure predictions to provide hypotheses for the improved affinity to this receptor subtype. Mutational analysis confirmed the hypotheses, indicating that loop C of the GABAA receptor α-subunit is the dominant molecular determinant of drug selectivity.
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Affiliation(s)
- Xenia Simeone
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Filip Koniuszewski
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Markus Müllegger
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Andreas Smetka
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Friederike Steudle
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Roshan Puthenkalam
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Margot Ernst
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Petra Scholze
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
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10
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Zahn N, Mikulsky BN, Roni MSR, Yocum GT, Mian MY, Knutson DE, Cook JM, Emala CW, Stafford DC, Arnold LA. Nebulized MIDD0301 Reduces Airway Hyperresponsiveness in Moderate and Severe Murine Asthma Models. ACS Pharmacol Transl Sci 2020; 3:1381-1390. [PMID: 33344908 PMCID: PMC7737320 DOI: 10.1021/acsptsci.0c00180] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Indexed: 01/19/2023]
Abstract
We report the relaxation of methacholine-constricted airways with nebulized MIDD0301, a positive allosteric γ-aminobutyric acid type A receptor (GABAAR) modulator. The therapeutic efficacy of nebulized MIDD0301 in reducing airway resistance was investigated in spontaneous breathing mice using a whole-body plethysmograph and in unconscious mice using a forced oscillation technique. Prophylactic nebulized MIDD0301 reduced subsequent methacholine-induced bronchoconstriction in ovalbumin and house dust mite allergic asthma models and in normal mice. Nebulized MIDD0301 exhibited comparable or better therapeutic potency compared to nebulized albuterol and oral montelukast. Prophylactic nebulized MIDD0301 was also effective in reducing bronchoconstriction, comparable to nebulized albuterol or fluticasone, in a steroid resistant asthma mouse model induced by intratracheal installation of lipopolysaccharide and interferon-gamma. Oral dexamethasone was ineffective in this model. Nebulized MIDD0301 was also effective in reversing bronchospasm when dosed after methacholine challenge comparable to albuterol. Pharmacokinetic studies showed that about 0.06% of nebulized MIDD0301 entered the mouse lung when using a whole body plethysmograph and therapeutic levels were sustained in the lung for at least 25 min. Consistent with previous reports on orally dosed MIDD0301, high doses of nebulized MIDD0301 resulted in minimal brain exposure and thus no observable adverse sensorimotor or respiratory depression effects occurred. In addition, no adverse cardiovascular effects were observed following 100 mg/kg i.p. dosing. These results further demonstrate that charged imidazodiazepine MIDD0301 can selectively target lung GABAAR without adverse motor, cardiovascular, or respiratory effects and inhaled dosing is effective in reducing bronchoconstriction in allergen and infectious lung inflammation.
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Affiliation(s)
- Nicolas
M. Zahn
- Department
of Chemistry and Biochemistry and the Milwaukee Institute for Drug
Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
| | | | - M. S. Rashid Roni
- Department
of Chemistry and Biochemistry and the Milwaukee Institute for Drug
Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
| | - Gene T. Yocum
- Department
of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York 10032, United States
| | - Md Yeunus Mian
- Department
of Chemistry and Biochemistry and the Milwaukee Institute for Drug
Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
| | - Daniel E. Knutson
- Department
of Chemistry and Biochemistry and the Milwaukee Institute for Drug
Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
| | - James M. Cook
- Department
of Chemistry and Biochemistry and the Milwaukee Institute for Drug
Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
| | - Charles W. Emala
- Department
of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York 10032, United States
| | - Douglas C. Stafford
- Department
of Chemistry and Biochemistry and the Milwaukee Institute for Drug
Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States,Pantherics
Incorporated, La Jolla, California 92037, United States
| | - Leggy A. Arnold
- Department
of Chemistry and Biochemistry and the Milwaukee Institute for Drug
Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States,Pantherics
Incorporated, La Jolla, California 92037, United States,
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11
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Gazzola M, Flamand N, Bossé Y. [Extracellular molecules controlling the contraction of airway smooth muscle and their potential contribution to bronchial hyperresponsiveness]. Rev Mal Respir 2020; 37:462-473. [PMID: 32487422 DOI: 10.1016/j.rmr.2020.03.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 03/12/2020] [Indexed: 02/06/2023]
Abstract
INTRODUCTION A significant portion of symptoms in some lung diseases results from an excessive constriction of airways due to the contraction of smooth muscle and bronchial hyperresponsiveness. A better understanding of the extracellular molecules that control smooth muscle contractility is necessary to identify the underlying causes of the problem. STATE OF KNOWLEDGE Almost a hundred molecules, some of which newly identified, influence the contractility of airway smooth muscle. While some molecules activate the contraction, others activate the relaxation, thus acting directly as bronchoconstrictors and bronchodilators, respectively. Other molecules do not affect contraction directly but rather influence it indirectly by modifying the effect of bronchoconstrictors and bronchodilators. These are called bronchomodulators. Some of these bronchomodulators increase the contractile effect of bronchoconstrictors and could thus contribute to bronchial hyperresponsiveness. PROSPECTS Considering the high number of molecules potentially involved, as well as the level of functional overlap between some of them, identifying the extracellular molecules responsible for excessive airway constriction in a patient is a major contemporary challenge.
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Affiliation(s)
| | | | - Y Bossé
- Université Laval, Québec, Canada.
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12
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Yim PD, Gallos G, Lee-Kong SA, Dan W, Wu AD, Xu D, Berkowitz DE, Emala CW. Novel Expression of GABAA Receptors on Resistance Arteries That Modulate Myogenic Tone. J Vasc Res 2020; 57:113-125. [PMID: 32097943 DOI: 10.1159/000505456] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 12/16/2019] [Indexed: 01/17/2023] Open
Abstract
The clinical administration of GABAergic medications leads to hypotension which has classically been attributed to the modulation of neuronal activity in the central and peripheral nervous systems. However, certain types of peripheral smooth muscle cells have been shown to express GABAA receptors, which modulate smooth muscle tone, by the activation of these chloride channels on smooth muscle cell plasma membranes. Limited prior studies demonstrate that non-human large-caliber capacitance blood vessels mounted on a wire myograph are responsive to GABAA ligands. We questioned whether GABAA receptors are expressed in human resistance arteries and whether they modulate myogenic tone. We demonstrate the novel expression of GABAA subunits on vascular smooth muscle from small-caliber human omental and mouse tail resistance arteries. We show that GABAA receptors modulate both plasma membrane potential and calcium responses in primary cultured cells from human resistance arteries. Lastly, we demonstrate functional physiologic modulation of myogenic tone via GABAA receptor activation in human and mouse arteries. Together, these studies demonstrate a previously unrecognized role for GABAA receptors in the modulation of myogenic tone in mouse and human resistance arteries.
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Affiliation(s)
- Peter D Yim
- Department of Anesthesiology, Columbia University, New York, New York, USA,
| | - George Gallos
- Department of Anesthesiology, Columbia University, New York, New York, USA
| | | | - William Dan
- Department of Anesthesiology, Columbia University, New York, New York, USA
| | - Amy D Wu
- Department of Anesthesiology, Columbia University, New York, New York, USA
| | - Dingbang Xu
- Department of Anesthesiology, Columbia University, New York, New York, USA
| | - Dan E Berkowitz
- Department of Anesthesiology and Perioperative Medicine, University of Alabama, Birmingham, Alabama, USA
| | - Charles W Emala
- Department of Anesthesiology, Columbia University, New York, New York, USA
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13
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Diazepam inhibited lipopolysaccharide (LPS)-induced pyroptotic cell death and alleviated pulmonary fibrosis in mice by specifically activating GABAA receptor α4-subunit. Biomed Pharmacother 2019; 118:109239. [DOI: 10.1016/j.biopha.2019.109239] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 07/11/2019] [Accepted: 07/16/2019] [Indexed: 12/27/2022] Open
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14
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Suleiman S, Klassen S, Katz I, Balakirski G, Krabbe J, von Stillfried S, Kintsler S, Braunschweig T, Babendreyer A, Spillner J, Kalverkamp S, Schröder T, Moeller M, Coburn M, Uhlig S, Martin C, Rieg AD. Argon reduces the pulmonary vascular tone in rats and humans by GABA-receptor activation. Sci Rep 2019; 9:1902. [PMID: 30760775 PMCID: PMC6374423 DOI: 10.1038/s41598-018-38267-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 12/21/2018] [Indexed: 12/11/2022] Open
Abstract
Argon exerts neuroprotection. Thus, it might improve patients' neurological outcome after cerebral disorders or cardiopulmonary resuscitation. However, limited data are available concerning its effect on pulmonary vessel and airways. We used rat isolated perfused lungs (IPL) and precision-cut lung slices (PCLS) of rats and humans to assess this topic. IPL: Airway and perfusion parameters, oedema formation and the pulmonary capillary pressure (Pcap) were measured and the precapillary and postcapillary resistance (Rpost) was calculated. In IPLs and PCLS, the pulmonary vessel tone was enhanced with ET-1 or remained unchanged. IPLs were ventilated and PCLS were gassed with argon-mixture or room-air. IPL: Argon reduced the ET-1-induced increase of Pcap, Rpost and oedema formation (p < 0.05). PCLS (rat): Argon relaxed naïve pulmonary arteries (PAs) (p < 0.05). PCLS (rat/human): Argon attenuated the ET-1-induced contraction in PAs (p < 0.05). Inhibition of GABAB-receptors abolished argon-induced relaxation (p < 0.05) in naïve or ET-1-pre-contracted PAs; whereas inhibition of GABAA-receptors only affected ET-1-pre-contracted PAs (p < 0.01). GABAA/B-receptor agonists attenuated ET-1-induced contraction in PAs and baclofen (GABAB-agonist) even in pulmonary veins (p < 0.001). PLCS (rat): Argon did not affect the airways. Finally, argon decreases the pulmonary vessel tone by activation of GABA-receptors. Hence, argon might be applicable in patients with pulmonary hypertension and right ventricular failure.
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Affiliation(s)
- Said Suleiman
- Institute of Pharmacology and Toxicology, Medical Faculty RWTH-Aachen, 52074, Aachen, Germany
| | - Sergej Klassen
- Institute of Pharmacology and Toxicology, Medical Faculty RWTH-Aachen, 52074, Aachen, Germany
| | - Ira Katz
- Medical Research & Development, Air Liquide Santé Internationale, Centre de Recherche Paris-Saclay, 78354, Jouy-en-Josas, France
| | - Galina Balakirski
- Institute of Pharmacology and Toxicology, Medical Faculty RWTH-Aachen, 52074, Aachen, Germany
| | - Julia Krabbe
- Institute of Pharmacology and Toxicology, Medical Faculty RWTH-Aachen, 52074, Aachen, Germany
| | | | - Svetlana Kintsler
- Institute of Pathology, Medical Faculty RWTH Aachen, 52074, Aachen, Germany
| | - Till Braunschweig
- Institute of Pathology, Medical Faculty RWTH Aachen, 52074, Aachen, Germany
| | - Aaron Babendreyer
- Institute of Pharmacology and Toxicology, Medical Faculty RWTH-Aachen, 52074, Aachen, Germany
| | - Jan Spillner
- Department of Cardiac and Thoracic Surgery, Medical Faculty RWTH Aachen, 52074, Aachen, Germany
| | - Sebastian Kalverkamp
- Department of Cardiac and Thoracic Surgery, Medical Faculty RWTH Aachen, 52074, Aachen, Germany
| | - Thomas Schröder
- Department of Surgery, Luisenhospital Aachen, 52064, Aachen, Germany
| | - Manfred Moeller
- Institute for Occupational, Social and Environmental Medicine, Medical Faculty RWTH Aachen, 52074, Aachen, Germany
| | - Mark Coburn
- Department of Anaesthesiology, Medical Faculty RWTH Aachen, 52074, Aachen, Germany
| | - Stefan Uhlig
- Institute of Pharmacology and Toxicology, Medical Faculty RWTH-Aachen, 52074, Aachen, Germany
| | - Christian Martin
- Institute of Pharmacology and Toxicology, Medical Faculty RWTH-Aachen, 52074, Aachen, Germany
| | - Annette D Rieg
- Department of Anaesthesiology, Medical Faculty RWTH Aachen, 52074, Aachen, Germany.
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15
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Yocum GT, Perez-Zoghbi JF, Danielsson J, Kuforiji AS, Zhang Y, Li G, Rashid Roni MS, Kodali R, Stafford DC, Arnold LA, Cook JM, Emala CW. A novel GABA A receptor ligand MIDD0301 with limited blood-brain barrier penetration relaxes airway smooth muscle ex vivo and in vivo. Am J Physiol Lung Cell Mol Physiol 2018; 316:L385-L390. [PMID: 30489155 DOI: 10.1152/ajplung.00356.2018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Airway smooth muscle (ASM) cells express GABA A receptors (GABAARs), and previous reports have demonstrated that GABAAR activators relax ASM. However, given the activity of GABAARs in central nervous system inhibitory neurotransmission, concern exists that these activators may lead to undesirable sedation. MIDD0301 is a novel imidazobenzodiazepine and positive allosteric modulator of the GABAAR with limited brain distribution, thus eliminating the potential for sedation. Here, we demonstrate that MIDD0301 relaxes histamine-contracted guinea pig ( P < 0.05, n = 6-9) and human ( P < 0.05, n = 6-10) tracheal smooth muscle ex vivo in organ bath experiments, dilates mouse peripheral airways ex vivo in precision-cut lung-slice experiments ( P < 0.001, n = 16 airways from three mice), and alleviates bronchoconstriction in vivo in mice, as assessed by the forced-oscillation technique ( P < 0.05, n = 6 mice). Only trace concentrations of the compound were detected in the brains of mice after inhalation of nebulized 5 mM MIDD0301. Given its favorable pharmacokinetic properties and demonstrated ability to relax ASM in a number of clinically relevant experimental paradigms, MIDD0301 is a promising drug candidate for bronchoconstrictive diseases, such as asthma.
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Affiliation(s)
- Gene T Yocum
- Department of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University , New York, New York
| | - Jose F Perez-Zoghbi
- Department of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University , New York, New York
| | - Jennifer Danielsson
- Department of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University , New York, New York
| | - Aisha S Kuforiji
- Department of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University , New York, New York
| | - Yi Zhang
- Department of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University , New York, New York
| | - Guanguan Li
- Department of Chemistry and Biochemistry, University of Wisconsin , Milwaukee, Wisconsin
| | - M S Rashid Roni
- Department of Chemistry and Biochemistry, University of Wisconsin , Milwaukee, Wisconsin
| | - Revathi Kodali
- Department of Chemistry and Biochemistry, University of Wisconsin , Milwaukee, Wisconsin
| | - Douglas C Stafford
- Milwaukee Institute for Drug Discovery, University of Wisconsin , Milwaukee, Wisconsin
| | - Leggy A Arnold
- Department of Chemistry and Biochemistry, University of Wisconsin , Milwaukee, Wisconsin.,Milwaukee Institute for Drug Discovery, University of Wisconsin , Milwaukee, Wisconsin
| | - James M Cook
- Department of Chemistry and Biochemistry, University of Wisconsin , Milwaukee, Wisconsin.,Milwaukee Institute for Drug Discovery, University of Wisconsin , Milwaukee, Wisconsin
| | - Charles W Emala
- Department of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University , New York, New York
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16
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Liu Y, Zheng J, Zhang HP, Zhang X, Wang L, Wood L, Wang G. Obesity-Associated Metabolic Signatures Correlate to Clinical and Inflammatory Profiles of Asthma: A Pilot Study. ALLERGY, ASTHMA & IMMUNOLOGY RESEARCH 2018; 10:628-647. [PMID: 30306746 PMCID: PMC6182193 DOI: 10.4168/aair.2018.10.6.628] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 05/27/2018] [Accepted: 06/01/2018] [Indexed: 02/05/2023]
Abstract
PURPOSE Obesity is associated with metabolic dysregulation, but the underlying metabolic signatures involving clinical and inflammatory profiles of obese asthma are largely unexplored. We aimed at identifying the metabolic signatures of obese asthma. METHODS Eligible subjects with obese (n = 11) and lean (n = 22) asthma underwent body composition and clinical assessment, sputum induction, and blood sampling. Sputum supernatant was assessed for interleukin (IL)-1β, -4, -5, -6, -13, and tumor necrosis factor (TNF)-α, and serum was detected for leptin, adiponectin and C-reactive protein. Untargeted gas chromatography time-of-flight mass spectrometry (GC-TOF-MS)-based metabolic profiles in sputum, serum and peripheral blood monocular cells (PBMCs) were analyzed by orthogonal projections to latent structures-discriminate analysis (OPLS-DA) and pathway topology enrichment analysis. The differential metabolites were further validated by correlation analysis with body composition, and clinical and inflammatory profiles. RESULTS Body composition, asthma control, and the levels of IL-1β, -4, -13, leptin and adiponectin in obese asthmatics were significantly different from those in lean asthmatics. OPLS-DA analysis revealed 28 differential metabolites that distinguished obese from lean asthmatic subjects. The validation analysis identified 18 potential metabolic signatures (11 in sputum, 4 in serum and 2 in PBMCs) of obese asthmatics. Pathway topology enrichment analysis revealed that cyanoamino acid metabolism, caffeine metabolism, alanine, aspartate and glutamate metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, pentose phosphate pathway in sputum, and glyoxylate and dicarboxylate metabolism, glycerolipid metabolism and pentose phosphate pathway in serum are suggested to be significant pathways related to obese asthma. CONCLUSIONS GC-TOF-MS-based metabolomics indicates obese asthma is characterized by a metabolic profile different from lean asthma. The potential metabolic signatures indicated novel immune-metabolic mechanisms in obese asthma with providing more phenotypic and therapeutic implications, which needs further replication and validation.
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Affiliation(s)
- Ying Liu
- Pneumology Group, Department of Integrated Traditional Chinese and Western Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, China
- Pneumology Group, Department of Integrated Traditional Chinese and Western Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Jing Zheng
- Department of Integrated Traditional Chinese and Western Medicine, Xinqiao Hospital, Third Military University, Chongqing, China
| | - Hong Ping Zhang
- Pneumology Group, Department of Integrated Traditional Chinese and Western Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, China
- Pneumology Group, Department of Integrated Traditional Chinese and Western Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Xin Zhang
- Pneumology Group, Department of Integrated Traditional Chinese and Western Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, China
- Pneumology Group, Department of Integrated Traditional Chinese and Western Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Lei Wang
- Pneumology Group, Department of Integrated Traditional Chinese and Western Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, China
- Pneumology Group, Department of Integrated Traditional Chinese and Western Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Lisa Wood
- Center for Asthma and Respiratory Diseases, Department of Respiratory and Sleep Medicine, John Hunter Hospital, Hunter Medical Research Institute, University of Newcastle, New Lambton, NSW, Australia
| | - Gang Wang
- Department of Respiratory and Critical Care Medicine, Clinical Research Center for Respiratory Disease, West China Hospital, Sichuan University, Chengdu, China.
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17
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Sieghart W, Savić MM. International Union of Basic and Clinical Pharmacology. CVI: GABA A Receptor Subtype- and Function-selective Ligands: Key Issues in Translation to Humans. Pharmacol Rev 2018; 70:836-878. [PMID: 30275042 DOI: 10.1124/pr.117.014449] [Citation(s) in RCA: 149] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2025] Open
Abstract
GABAA receptors are the major inhibitory transmitter receptors in the brain. They are ligand-gated chloride channels and the site of action of benzodiazepines, barbiturates, neuroactive steroids, anesthetics, and convulsants. GABAA receptors are composed of five subunits that can belong to different subunit classes. The existence of 19 homologous subunits and their distinct regional, cellular, and subcellular distribution gives rise to a large number of GABAA receptor subtypes with distinct pharmacology, which modulate different functions of the brain. A variety of compounds have been identified that were claimed to modulate selectively individual GABAA receptor subtypes. However, many of these compounds have only incompletely been investigated or, in addition to a preferential modulation of a receptor subtype, also modulate other subtypes at similar concentrations. Although their differential efficacy at distinct receptor subtypes reduced side effects in behavioral experiments in rodents, the exact receptor subtypes mediating their behavioral effects cannot be unequivocally delineated. In addition, the discrepant in vivo effects of some of these compounds in rodents and man raised doubts on the applicability of the concept of receptor subtype selectivity as a guide for the development of clinically useful drugs. Here, we provide an up-to-date review on the currently available GABAA receptor subtype-selective ligands. We present data on their actual activity at GABAA receptor subtypes, discuss the translational aspect of subtype-selective drugs, and make proposals for the future development of ligands with better anxioselectivity in humans. Finally, we discuss possible ways to strengthen the conclusions of behavioral studies with the currently available drugs.
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Affiliation(s)
- Werner Sieghart
- Center for Brain Research, Medical University of Vienna, Vienna, Austria (W.S.) and Department of Pharmacology, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia (M.M.S.)
| | - Miroslav M Savić
- Center for Brain Research, Medical University of Vienna, Vienna, Austria (W.S.) and Department of Pharmacology, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia (M.M.S.)
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18
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The Benzodiazepine Binding Sites of GABAA Receptors. Trends Pharmacol Sci 2018; 39:659-671. [DOI: 10.1016/j.tips.2018.03.006] [Citation(s) in RCA: 107] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 03/15/2018] [Accepted: 03/22/2018] [Indexed: 11/24/2022]
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19
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Forkuo GS, Nieman AN, Yuan NY, Kodali R, Yu OB, Zahn NM, Jahan R, Li G, Stephen MR, Guthrie ML, Poe MM, Hartzler BD, Harris TW, Yocum GT, Emala CW, Steeber DA, Stafford DC, Cook JM, Arnold LA. Alleviation of Multiple Asthmatic Pathologic Features with Orally Available and Subtype Selective GABA A Receptor Modulators. Mol Pharm 2017; 14:2088-2098. [PMID: 28440659 PMCID: PMC5497587 DOI: 10.1021/acs.molpharmaceut.7b00183] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
We describe pharmacokinetic and pharmacodynamic properties of two novel oral drug candidates for asthma. Phenolic α4β3γ2 GABAAR selective compound 1 and acidic α5β3γ2 selective GABAAR positive allosteric modulator compound 2 relaxed airway smooth muscle ex vivo and attenuated airway hyperresponsiveness (AHR) in a murine model of asthma. Importantly, compound 2 relaxed acetylcholine contracted human tracheal airway smooth muscle strips. Oral treatment of compounds 1 and 2 decreased eosinophils in bronchoalveolar lavage fluid in ovalbumin sensitized and challenged mice, thus exhibiting anti-inflammatory properties. Additionally, compound 1 reduced the number of lung CD4+ T lymphocytes and directly modulated their transmembrane currents by acting on GABAARs. Excellent pharmacokinetic properties were observed, including long plasma half-life (up to 15 h), oral availability, and extremely low brain distribution. In conclusion, we report the selective targeting of GABAARs expressed outside the brain and demonstrate reduction of AHR and airway inflammation with two novel orally available GABAAR ligands.
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Affiliation(s)
- Gloria S. Forkuo
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - Amanda N. Nieman
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - Nina Y. Yuan
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - Revathi Kodali
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - Olivia B. Yu
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - Nicolas M. Zahn
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - Rajwana Jahan
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - Guanguan Li
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - Michael Rajesh Stephen
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - Margaret L. Guthrie
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - Michael M. Poe
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - Benjamin D. Hartzler
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - Ted W. Harris
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - Gene T. Yocum
- Department of Anesthesiology, Columbia University, New York, New York, 10032
| | - Charles W. Emala
- Department of Anesthesiology, Columbia University, New York, New York, 10032
| | - Douglas A. Steeber
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - Douglas C. Stafford
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - James M. Cook
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
| | - Leggy A. Arnold
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53201
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20
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Yocum GT, Turner DL, Danielsson J, Barajas MB, Zhang Y, Xu D, Harrison NL, Homanics GE, Farber DL, Emala CW. GABA A receptor α 4-subunit knockout enhances lung inflammation and airway reactivity in a murine asthma model. Am J Physiol Lung Cell Mol Physiol 2017; 313:L406-L415. [PMID: 28473323 PMCID: PMC5582940 DOI: 10.1152/ajplung.00107.2017] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 04/06/2017] [Accepted: 04/30/2017] [Indexed: 01/07/2023] Open
Abstract
Emerging evidence indicates that hypnotic anesthetics affect immune function. Many anesthetics potentiate γ-aminobutyric acid A receptor (GABAAR) activation, and these receptors are expressed on multiple subtypes of immune cells, providing a potential mechanistic link. Like immune cells, airway smooth muscle (ASM) cells also express GABAARs, particularly isoforms containing α4-subunits, and activation of these receptors leads to ASM relaxation. We sought to determine if GABAAR signaling modulates the ASM contractile and inflammatory phenotype of a murine allergic asthma model utilizing GABAAR α4-subunit global knockout (KO; Gabra40/0 ) mice. Wild-type (WT) and Gabra4 KO mice were sensitized with house dust mite (HDM) antigen or exposed to PBS intranasally 5 days/wk for 3 wk. Ex vivo tracheal rings from HDM-sensitized WT and Gabra4 KO mice exhibited similar magnitudes of acetylcholine-induced contractile force and isoproterenol-induced relaxation (P = not significant; n = 4). In contrast, in vivo airway resistance (flexiVent) was significantly increased in Gabra4 KO mice (P < 0.05, n = 8). Moreover, the Gabra4 KO mice demonstrated increased eosinophilic lung infiltration (P < 0.05; n = 4) and increased markers of lung T-cell activation/memory (CD62L low, CD44 high; P < 0.01, n = 4). In vitro, Gabra4 KO CD4+ cells produced increased cytokines and exhibited increased proliferation after stimulation of the T-cell receptor as compared with WT CD4+ cells. These data suggest that the GABAAR α4-subunit plays a role in immune cell function during allergic lung sensitization. Thus GABAAR α4-subunit-specific agonists have the therapeutic potential to treat asthma via two mechanisms: direct ASM relaxation and inhibition of airway inflammation.
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Affiliation(s)
- Gene T Yocum
- Department of Anesthesiology, Columbia University, New York, New York;
| | - Damian L Turner
- Columbia Center for Translational Immunology, New York, New York
| | | | - Matthew B Barajas
- Department of Anesthesiology, Columbia University, New York, New York
| | - Yi Zhang
- Department of Anesthesiology, Columbia University, New York, New York
| | - Dingbang Xu
- Department of Anesthesiology, Columbia University, New York, New York
| | - Neil L Harrison
- Department of Anesthesiology, Columbia University, New York, New York.,Department of Pharmacology, Columbia University, New York, New York
| | - Gregg E Homanics
- Departments of Anesthesiology, Neurobiology, and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania; and
| | - Donna L Farber
- Columbia Center for Translational Immunology, New York, New York.,Department of Surgery and Microbiology and Immunology, Columbia University, New York, New York
| | - Charles W Emala
- Department of Anesthesiology, Columbia University, New York, New York
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21
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Jahan R, Stephen MR, Forkuo GS, Kodali R, Guthrie ML, Nieman AN, Yuan NY, Zahn NM, Poe MM, Li G, Yu OB, Yocum GT, Emala CW, Stafford DC, Cook JM, Arnold LA. Optimization of substituted imidazobenzodiazepines as novel asthma treatments. Eur J Med Chem 2016; 126:550-560. [PMID: 27915170 DOI: 10.1016/j.ejmech.2016.11.045] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 11/19/2016] [Accepted: 11/21/2016] [Indexed: 12/14/2022]
Abstract
We describe the synthesis of analogs of XHE-III-74, a selective α4β3γ2 GABAAR ligand, shown to relax airway smooth muscle ex vivo and reduce airway hyperresponsiveness in a murine asthma model. To improve properties of this compound as an asthma therapeutic, a series of analogs with a deuterated methoxy group in place of methoxy group at C-8 position was evaluated for isotope effects in preclinical assays; including microsomal stability, cytotoxicity, and sensorimotor impairment. The deuterated compounds were equally or more metabolically stable than the corresponding non-deuterated analogs and increased sensorimotor impairment was observed for some deuterated compounds. Thioesters were more cytotoxic in comparison to other carboxylic acid derivatives of this compound series. The most promising compound 16 identified from the in vitro screens also strongly inhibited smooth muscle constriction in ex vivo guinea pig tracheal rings. Smooth muscle relaxation, determined by reduction of airway hyperresponsiveness with a murine ovalbumin sensitized and challenged model, showed that 16 was efficacious at low methacholine concentrations. However, this effect was limited due to suboptimal pharmacokinetics of 16. Based on these findings, further analogs of XHE-III-74 will be investigated to improve in vivo metabolic stability while retaining the efficacy at lung tissues involved in asthma pathology.
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Affiliation(s)
- Rajwana Jahan
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, United States
| | - Michael Rajesh Stephen
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, United States
| | - Gloria S Forkuo
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, United States
| | - Revathi Kodali
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, United States
| | - Margaret L Guthrie
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, United States
| | - Amanda N Nieman
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, United States
| | - Nina Y Yuan
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, United States
| | - Nicolas M Zahn
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, United States
| | - Michael M Poe
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, United States
| | - Guanguan Li
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, United States
| | - Olivia B Yu
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, United States
| | - Gene T Yocum
- Department of Anesthesiology, Columbia University, New York, NY, 10032, United States
| | - Charles W Emala
- Department of Anesthesiology, Columbia University, New York, NY, 10032, United States
| | - Douglas C Stafford
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, United States
| | - James M Cook
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, United States.
| | - Leggy A Arnold
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, United States.
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22
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Prakash YS. Emerging concepts in smooth muscle contributions to airway structure and function: implications for health and disease. Am J Physiol Lung Cell Mol Physiol 2016; 311:L1113-L1140. [PMID: 27742732 DOI: 10.1152/ajplung.00370.2016] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 10/06/2016] [Indexed: 12/15/2022] Open
Abstract
Airway structure and function are key aspects of normal lung development, growth, and aging, as well as of lung responses to the environment and the pathophysiology of important diseases such as asthma, chronic obstructive pulmonary disease, and fibrosis. In this regard, the contributions of airway smooth muscle (ASM) are both functional, in the context of airway contractility and relaxation, as well as synthetic, involving production and modulation of extracellular components, modulation of the local immune environment, cellular contribution to airway structure, and, finally, interactions with other airway cell types such as epithelium, fibroblasts, and nerves. These ASM contributions are now found to be critical in airway hyperresponsiveness and remodeling that occur in lung diseases. This review emphasizes established and recent discoveries that underline the central role of ASM and sets the stage for future research toward understanding how ASM plays a central role by being both upstream and downstream in the many interactive processes that determine airway structure and function in health and disease.
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Affiliation(s)
- Y S Prakash
- Departments of Anesthesiology, and Physiology & Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
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23
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Pera T, Penn RB. Bronchoprotection and bronchorelaxation in asthma: New targets, and new ways to target the old ones. Pharmacol Ther 2016; 164:82-96. [PMID: 27113408 PMCID: PMC4942340 DOI: 10.1016/j.pharmthera.2016.04.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 04/07/2016] [Indexed: 01/01/2023]
Abstract
Despite over 50years of inhaled beta-agonists and corticosteroids as the default management or rescue drugs for asthma, recent research suggests that new therapeutic options are likely to emerge. This belief stems from both an improved understanding of what causes and regulates airway smooth muscle (ASM) contraction, and the identification of new targets whose inhibition or activation can relax ASM. In this review we discuss the recent findings that provide new insight into ASM contractile regulation, a revolution in pharmacology that identifies new ways to "tune" G protein-coupled receptors to improve therapeutic efficacy, and the discovery of several novel targets/approaches capable of effecting bronchoprotection or bronchodilation.
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Affiliation(s)
- Tonio Pera
- Center for Translational Medicine and Jane and Leonard Korman Lung Center, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States.
| | - Raymond B Penn
- Center for Translational Medicine and Jane and Leonard Korman Lung Center, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States.
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24
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Forkuo GS, Guthrie ML, Yuan NY, Nieman AN, Kodali R, Jahan R, Stephen MR, Yocum GT, Treven M, Poe MM, Li G, Yu OB, Hartzler BD, Zahn NM, Ernst M, Emala CW, Stafford DC, Cook JM, Arnold LA. Development of GABAA Receptor Subtype-Selective Imidazobenzodiazepines as Novel Asthma Treatments. Mol Pharm 2016; 13:2026-38. [PMID: 27120014 DOI: 10.1021/acs.molpharmaceut.6b00159] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Recent studies have demonstrated that subtype-selective GABAA receptor modulators are able to relax precontracted human airway smooth muscle ex vivo and reduce airway hyper-responsiveness in mice upon aerosol administration. Our goal in this study was to investigate systemic administration of subtype-selective GABAA receptor modulators to alleviate bronchoconstriction in a mouse model of asthma. Expression of GABAA receptor subunits was identified in mouse lungs, and the effects of α4-subunit-selective GABAAR modulators, XHE-III-74EE and its metabolite XHE-III-74A, were investigated in a murine model of asthma (ovalbumin sensitized and challenged BALB/c mice). We observed that chronic treatment with XHE-III-74EE significantly reduced airway hyper-responsiveness. In addition, acute treatment with XHE-III-74A but not XHE-III-74EE decreased airway eosinophilia. Immune suppressive activity was also shown in activated human T-cells with a reduction in IL-2 expression and intracellular calcium concentrations [Ca(2+)]i in the presence of GABA or XHE-III-74A, whereas XHE-III-74EE showed only partial reduction of [Ca(2+)]i and no inhibition of IL-2 secretion. However, both compounds significantly relaxed precontracted tracheal rings ex vivo. Overall, we conclude that the systemic delivery of a α4-subunit-selective GABAAR modulator shows good potential for a novel asthma therapy; however, the pharmacokinetic properties of this class of drug candidates have to be improved to enable better beneficial systemic pharmacodynamic effects.
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Affiliation(s)
- Gloria S Forkuo
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
| | - Margaret L Guthrie
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
| | - Nina Y Yuan
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
| | - Amanda N Nieman
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
| | - Revathi Kodali
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
| | - Rajwana Jahan
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
| | - Michael R Stephen
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
| | - Gene T Yocum
- Department of Anesthesiology, Columbia University , New York, New York 10032, United States
| | - Marco Treven
- Department of Molecular Neurosciences, Medical University of Vienna , 1090 Vienna, Austria
| | - Michael M Poe
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
| | - Guanguan Li
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
| | - Olivia B Yu
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
| | - Benjamin D Hartzler
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
| | - Nicolas M Zahn
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
| | - Margot Ernst
- Department of Molecular Neurosciences, Medical University of Vienna , 1090 Vienna, Austria
| | - Charles W Emala
- Department of Anesthesiology, Columbia University , New York, New York 10032, United States
| | - Douglas C Stafford
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
| | - James M Cook
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
| | - Leggy A Arnold
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
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