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Bojić MG, Treven M, Pandey KP, Tiruveedhula VVNPB, Santrač A, Đukanović Đ, Vojinović N, Amidžić L, Škrbić R, Scholze P, Ernst M, Cook JM, Savić MM. Vascular effects of midazolam, flumazenil, and a novel imidazobenzodiazepine MP-III-058 on isolated rat aorta. Can J Physiol Pharmacol 2024; 102:206-217. [PMID: 37909404 DOI: 10.1139/cjpp-2023-0285] [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] [Indexed: 11/03/2023]
Abstract
Hypotensive influences of benzodiazepines and other GABAA receptor ligands, recognized in clinical practice, seem to stem from the existence of "vascular" GABAA receptors in peripheral blood vessels, besides any mechanisms in the central and peripheral nervous systems. We aimed to further elucidate the vasodilatatory effects of ligands acting through GABAA receptors. Using immunohistochemistry, the rat aortic smooth muscle layer was found to express GABAA γ2 and α1-5 subunit proteins. To confirm the role of "vascular" GABAA receptors, we investigated the vascular effects of standard benzodiazepines, midazolam, and flumazenil, as well as the novel compound MP-III-058. Using two-electrode voltage clamp electrophysiology and radioligand binding assays, MP-III-058 was found to have modest binding but substantial functional selectivity for α5β3γ2 over other αxβ3γ2 GABAA receptors. Tissue bath assays revealed comparable vasodilatory effects of MP-III-058 and midazolam, both of which at 100 µmol/L concentrations had efficacy similar to prazosin. Flumazenil exhibited weak vasoactivity per se, but significantly prevented the relaxant effects of midazolam and MP-III-058. These studies indicate the existence of functional GABAA receptors in the rat aorta, where ligands exert vasodilatory effects by positive modulation of the benzodiazepine binding site, suggesting the potential for further quest for leads with optimized pharmacokinetic properties as prospective adjuvant vasodilators.
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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
| | - Marco Treven
- Neurology Department, Medical University of Vienna, Vienna, Austria
| | - Kamal P Pandey
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - V V N Phani Babu Tiruveedhula
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Anja Santrač
- Department of Pharmacology, Faculty of Pharmacy, University of Belgrade, Belgrade 11000, Serbia
| | - Đorđe Đukanović
- Faculty of Medicine, Center for Biomedical Research, University of Banja Luka, Banja Luka 78000, Republic of Srpska, Bosnia and Herzegovina
| | - Nataša Vojinović
- Faculty of Medicine, Center for Biomedical Research, University of Banja Luka, Banja Luka 78000, Republic of Srpska, Bosnia and Herzegovina
| | - Ljiljana Amidžić
- Faculty of Medicine, Center for Biomedical Research, University of Banja Luka, Banja Luka 78000, Republic of Srpska, Bosnia and Herzegovina
| | - Ranko Škrbić
- Faculty of Medicine, Center for Biomedical Research, University of Banja Luka, Banja Luka 78000, Republic of Srpska, Bosnia and Herzegovina
| | - Petra Scholze
- Department of Pathobiology of the Nervous SystemCenter for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Margot Ernst
- Department of Pathobiology of the Nervous SystemCenter for Brain Research, Medical University of Vienna, Vienna, Austria
| | - James M Cook
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Miroslav M Savić
- Department of Pharmacology, Faculty of Pharmacy, University of Belgrade, Belgrade 11000, Serbia
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Romanova OL, Blagonravov ML, Djuvalyakov PG, Barinov EK, Ershov AV, Kislov MA. [Features of lung damage in baclofen poisoning]. Sud Med Ekspert 2024; 67:29-33. [PMID: 38353012 DOI: 10.17116/sudmed20246701129] [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] [Indexed: 02/16/2024]
Abstract
OBJECTIVE To reveal pathological lung changes in baclofen poisoning and to assess their dynamics. MATERIAL AND METHODS The experiment included 20 mature (at age 20 weeks) male rats of Wistar line weighing 290-350 gr. The animals were divided into 3 study groups (5 rats in each) depending on experiment's duration after 85 mg/kg baclofen administration: 3, 4.5 and 24 h in the 1st, 2nd and 3rd groups, respectively. Control group consisted of 5 animals without baclofen administration. RESULTS A number of pathological reactions, including circulatory disorder (venular and capillary congestion, hemorrhage in interalveolar septa, alveoli, sludge) and the appearance of emphysema loci (interalveolar septa at emphysema loci are thinned), alternating with atelectases and dystelectases. The area taken up by vessels after 4.5 h. baclofen administration was statistically significantly higher than in control group, and after 24 h. - statistically significantly higher than in 4.5 h. The area with white blood cells and WBC/IAP ratio after 4.5 h of baclofen administration were statistically significantly higher than in control group after 3 and 24 h of administration. The number of white blood cells, giving PAS positive reaction, increases during baclofen administration. The complex of pathological lung changes, revealed by ourselves, has a certain dynamics. CONCLUSION The data on morphological lung changes combined with results of chemical examination can be used to diagnose baclofen poisoning and to determine the time elapsed since this medicine administration.
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Affiliation(s)
- O L Romanova
- Russian University of People Friendship, Moscow, Russia
- Avtsyn Research Institute of Human Morphology «Petrovsky Russian Scientific Center of Surgery», Moscow, Russia
| | | | - P G Djuvalyakov
- Russian University of People Friendship, Moscow, Russia
- Avtsyn Research Institute of Human Morphology «Petrovsky Russian Scientific Center of Surgery», Moscow, Russia
| | - E Kh Barinov
- Russian University of People Friendship, Moscow, Russia
- A.I. Yevdokimov Moscow State University of Medicine and Dentistry, Moscow, Russia
| | - A V Ershov
- Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitation, Moscow, Russia
| | - M A Kislov
- Pirogov Russian National Research Medical University, Moscow, Russia
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Romanova OL, Blagonravov ML, Torshin VI, Dzhuvalyakov PG, Ershov AV, Kislov MA, Magulaev AM. The Effect of the Toxic Dose of Baclofen on Selected Parameters of the Cardiovascular and Respiratory Systems. Bull Exp Biol Med 2023; 175:777-780. [PMID: 37979027 DOI: 10.1007/s10517-023-05945-5] [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: 04/06/2023] [Indexed: 11/19/2023]
Abstract
The effect of the toxic dose of the muscle relaxant baclofen on the parameters of the cardiovascular and respiratory systems was studied in adult male Wistar rats (n=20). Systolic and diastolic BP, HR, and respiratory rate were measured; histological changes in the lungs 3, 4.5, and 24 h after drug administration. Baclofen was administered orally in a sublethal toxic dose of 85 mg/kg under anesthesia. Cardiac activity was analyzed using RSM physiological indicators monitoring system with MouseMonitor S (Indus Instruments) software. Histological examination was performed by light microscopy. Baclofen significantly decreased the respiratory rate and increased HR and BP. Histological examination of the lungs revealed a complex of general pathological processes, such as local circulatory disorders (venular and capillary fullness, sludge), leukocyte infiltration of the interalveolar septa and their thickening due to edema. These findings can be used to estimate the time elapsed after baclofen treatment.
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Affiliation(s)
- O L Romanova
- Institute of Medicine, Peoples' Friendship University of Russia (RUDN University), Moscow, Russia.
- A. P. Avtsyn Research Institute of Human Morphology, A. P. Petrovsky Russian Research Center of Surgery, Moscow, Russia.
| | - M L Blagonravov
- Institute of Medicine, Peoples' Friendship University of Russia (RUDN University), Moscow, Russia
| | - V I Torshin
- Institute of Medicine, Peoples' Friendship University of Russia (RUDN University), Moscow, Russia
| | - P G Dzhuvalyakov
- A. P. Avtsyn Research Institute of Human Morphology, A. P. Petrovsky Russian Research Center of Surgery, Moscow, Russia
| | - A V Ershov
- Federal Research Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia
- I. M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation (Sechenov University), Moscow, Russia
| | - M A Kislov
- I. M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation (Sechenov University), Moscow, Russia
| | - A M Magulaev
- I. M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation (Sechenov University), Moscow, Russia
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Romero-Martínez BS, Sommer B, Solís-Chagoyán H, Calixto E, Aquino-Gálvez A, Jaimez R, Gomez-Verjan JC, González-Avila G, Flores-Soto E, Montaño LM. Estrogenic Modulation of Ionic Channels, Pumps and Exchangers in Airway Smooth Muscle. Int J Mol Sci 2023; 24:ijms24097879. [PMID: 37175587 PMCID: PMC10178541 DOI: 10.3390/ijms24097879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 02/28/2023] [Accepted: 02/28/2023] [Indexed: 05/15/2023] Open
Abstract
To preserve ionic homeostasis (primarily Ca2+, K+, Na+, and Cl-), in the airway smooth muscle (ASM) numerous transporters (channels, exchangers, and pumps) regulate the influx and efflux of these ions. Many of intracellular processes depend on continuous ionic permeation, including exocytosis, contraction, metabolism, transcription, fecundation, proliferation, and apoptosis. These mechanisms are precisely regulated, for instance, through hormonal activity. The lipophilic nature of steroidal hormones allows their free transit into the cell where, in most cases, they occupy their cognate receptor to generate genomic actions. In the sense, estrogens can stimulate development, proliferation, migration, and survival of target cells, including in lung physiology. Non-genomic actions on the other hand do not imply estrogen's intracellular receptor occupation, nor do they initiate transcription and are mostly immediate to the stimulus. Among estrogen's non genomic responses regulation of calcium homeostasis and contraction and relaxation processes play paramount roles in ASM. On the other hand, disruption of calcium homeostasis has been closely associated with some ASM pathological mechanism. Thus, this paper intends to summarize the effects of estrogen on ionic handling proteins in ASM. The considerable diversity, range and power of estrogens regulates ionic homeostasis through genomic and non-genomic mechanisms.
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Affiliation(s)
- Bianca S Romero-Martínez
- Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico
| | - Bettina Sommer
- Laboratorio de Hiperreactividad Bronquial, Instituto Nacional de Enfermedades Respiratorias "Ismael Cosío Villegas", Ciudad de México 14080, Mexico
| | - Héctor Solís-Chagoyán
- Neurociencia Cognitiva Evolutiva, Centro de Investigación en Ciencias Cognitivas, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Mexico
| | - Eduardo Calixto
- Departamento de Neurobiología, Dirección de Investigación en Neurociencias, Instituto Nacional de Psiquiatría "Ramón de la Fuente Muñiz", Ciudad de México 14370, Mexico
| | - Arnoldo Aquino-Gálvez
- Laboratorio de Biología Molecular, Departamento de Fibrosis Pulmonar, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, México City 14080, Mexico
| | - Ruth Jaimez
- Laboratorio de Estrógenos y Hemostasis, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico
| | - Juan C Gomez-Verjan
- Dirección de Investigación, Instituto Nacional de Geriatría (INGER), Ciudad de México 10200, Mexico
| | - Georgina González-Avila
- Laboratorio de Oncología Biomédica, Instituto Nacional de Enfermedades Respiratorias "Ismael Cosío Villegas", México City 14080, Mexico
| | - Edgar Flores-Soto
- Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico
| | - Luis M Montaño
- Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico
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Gong R, Liu X, Zhao J. Electroacupuncture-induced activation of GABAergic system alleviates airway inflammation in asthma model by suppressing TLR4/MyD88/NF-κB signaling pathway. Chin Med J (Engl) 2023; 136:451-460. [PMID: 36867547 PMCID: PMC10106183 DOI: 10.1097/cm9.0000000000002314] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Indexed: 03/04/2023] Open
Abstract
BACKGROUND Electroacupuncture (EA) has been shown to attenuate airway inflammation in asthmatic mice; however, the underlying mechanism is not fully understood. Studies have shown that EA can significantly increase the inhibitory neurotransmitter γ-aminobutyric acid (GABA) content in mice, and can also increase the expression level of GABA type A receptor (GABAAR). Furthermore, activating GABAAR may relieve inflammation in asthma by suppressing toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)/nuclear factor-kappa B (NF-κB) signaling pathway. Therefore, this study aimed to investigate the role of GABAergic system and TLR4/MyD88/NF-κB signaling pathway in asthmatic mice treated with EA. METHODS A mouse model of asthma was established, and a series of methods including Western blot and histological staining assessment were employed to detect the level of GABA, and expressions of GABAAR and TLR4/MyD88/NF-κB in lung tissue. In addition, GABAAR antagonist was used to further validate the role and mechanism of GABAergic system in mediating the therapeutic effect of EA in asthma. RESULTS The mouse model of asthma was established successfully, and EA was verified to alleviate airway inflammation in asthmatic mice. The release of GABA and the expression of GABAAR were significantly increased in asthmatic mice treated with EA compared with untreated asthmatic mice ( P < 0.01), and the TLR4/MyD88/NF-κB signaling pathway was down-regulated. Moreover, inhibition of GABAAR attenuated the beneficial effects of EA in asthma, including the regulation of airway resistance and inflammation, as well as the inhibitory effects on TLR4/MyD88/NF-κB signaling pathway. CONCLUSION Our findings suggest that GABAergic system may be involved in mediating the therapeutic effect of EA in asthma, possibly by suppressing the TLR4/MyD88/NF-κB signaling pathway.
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Affiliation(s)
- Ruisong Gong
- Department of Anesthesia, China–Japan Friendship Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100029, China
| | - Xiaowen Liu
- Department of Anesthesia, China–Japan Friendship Hospital, Beijing 100029, China
| | - Jing Zhao
- Department of Anesthesia, China–Japan Friendship Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100029, China
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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] [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 MedicineThomas Jefferson UniversityPhiladelphia, Pennsylvania
| | - Steven S. An
- Rutgers Institute for Translational Medicine and ScienceNew Brunswick, New Jersey,Rutgers-Robert Wood Johnson Medical SchoolThe State University of New JerseyPiscataway, New Jersey
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Romanova OL, Chauhan M, Blagonravov ML, Kislov MA, Ershov AV, Krupin KN. Baclofen (fun drug) and ethanol combined poisoning in humans: A histopathology and morphometry model. J Forensic Leg Med 2022; 90:102373. [PMID: 35671675 DOI: 10.1016/j.jflm.2022.102373] [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: 01/19/2022] [Revised: 05/01/2022] [Accepted: 05/23/2022] [Indexed: 10/18/2022]
Abstract
BACKGROUND - This study intends to address the scarcity of data regarding the pathogenesis of Baclofen poisoning in humans, which has seen a recent increase, worldwide, especially amongst the young people. Another reason for the conduction of this study was lack of the substantial data about the histo-pathological findings of lungs, in synergistic toxicity of Baclofen with Ethanol, in-spite of it being very common in humans, and both being respiratory depressant with similar mechanism of action. PURPOSE - The authors aimed to understand the pathogenesis of fatal poisonings in humans due to Baclofen in combination with Ethanol via an animal research model. The enhancement of the overall scientific literature by extending research along the lines of the handful studies available in this regard was another adjunct goal of the study. MATERIAL AND METHODS Fifteen Wistar rats were divided into control and test group of five and ten subjects respectively. The test group was further divided into two sub-groups of five each, with Baclofen administered to one, and it in conjunction with Ethanol to the other, in lowest dosages adjusted for the humans. Rats in both the groups were euthanized by dislocation of the cervical vertebrae for the histopathology examination. RESULTS Capillary and venous plethora, hemorrhages in the inter-alveolar septi, hemorrhages into the alveoli and sludging was seen in the 1st sub-group. The plethora of venules, capillaries and arterioles, with sludging by the WBC (white blood corpuscle) infiltrates was seen in the 2nd sub-group. Desquamation of the ciliated epithelium and edematous thickening of the intra-alveolar septi, along with features suggestive of the peri-vascular edema was seen in the 2nd sub-group. The morphometric analysis of the micro vessels showed a significantly higher value of the arteriolar diameter in the 2nd sub-group, in comparison to 1st, but the venular diameter in the two sub-groups did not differ to any extent.
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Affiliation(s)
- O L Romanova
- Department of General Physiology, Medical Institute of Russian University of People Friendship, Research Institute of Human Morphology, Moscow, Russia.
| | - M Chauhan
- Department of Forensic Medicine and Toxicology, Government Medical College and Hospital, Chandigarh, 160030, India.
| | - M L Blagonravov
- Department of General Pathology and Pathological Physiology, Medical Institute of Russian University of People Friendship, Moscow, Russia.
| | - M A Kislov
- Department of Forensic Medicine, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia.
| | - A V Ershov
- Institute of General Resuscitation Named After V. A. Negovsky Federal State Budgetary Scientific Institution, Federal Scientific and Clinical Center of Reаnimatology and Rehabilitation, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia.
| | - K N Krupin
- Department of Forensic Medicine, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia.
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The Case for Clinical Trials with Novel GABAergic Drugs in Diabetes Mellitus and Obesity. Life (Basel) 2022; 12:life12020322. [PMID: 35207609 PMCID: PMC8876029 DOI: 10.3390/life12020322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 02/09/2022] [Accepted: 02/16/2022] [Indexed: 11/17/2022] Open
Abstract
Obesity and diabetes mellitus have become the surprising menaces of relative economic well-being worldwide. Gamma amino butyric acid (GABA) has a prominent role in the control of blood glucose, energy homeostasis as well as food intake at several levels of regulation. The effects of GABA in the body are exerted through ionotropic GABAA and metabotropic GABAB receptors. This treatise will focus on the pharmacologic targeting of GABAA receptors to reap beneficial therapeutic effects in diabetes mellitus and obesity. A new crop of drugs selectively targeting GABAA receptors has been under investigation for efficacy in stroke recovery and cognitive deficits associated with schizophrenia. Although these trials have produced mixed outcomes the compounds are safe to use in humans. Preclinical evidence is summarized here to support the rationale of testing some of these compounds in diabetic patients receiving insulin in order to achieve better control of blood glucose levels and to combat the decline of cognitive performance. Potential therapeutic benefits could be achieved (i) By resetting the hypoglycemic counter-regulatory response; (ii) Through trophic actions on pancreatic islets, (iii) By the mobilization of antioxidant defence mechanisms in the brain. Furthermore, preclinical proof-of-concept work, as well as clinical trials that apply the novel GABAA compounds in eating disorders, e.g., olanzapine-induced weight-gain, also appear warranted.
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Ghit A, Assal D, Al-Shami AS, Hussein DEE. GABA A receptors: structure, function, pharmacology, and related disorders. J Genet Eng Biotechnol 2021; 19:123. [PMID: 34417930 PMCID: PMC8380214 DOI: 10.1186/s43141-021-00224-0] [Citation(s) in RCA: 109] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 08/08/2021] [Indexed: 02/03/2023]
Abstract
Background γ-Aminobutyric acid sub-type A receptors (GABAARs) are the most prominent inhibitory neurotransmitter receptors in the CNS. They are a family of ligand-gated ion channel with significant physiological and therapeutic implications. Main body GABAARs are heteropentamers formed from a selection of 19 subunits: six α (alpha1-6), three β (beta1-3), three γ (gamma1-3), three ρ (rho1-3), and one each of the δ (delta), ε (epsilon), π (pi), and θ (theta) which result in the production of a considerable number of receptor isoforms. Each isoform exhibits distinct pharmacological and physiological properties. However, the majority of GABAARs are composed of two α subunits, two β subunits, and one γ subunit arranged as γ2β2α1β2α1 counterclockwise around the center. The mature receptor has a central chloride ion channel gated by GABA neurotransmitter and modulated by a variety of different drugs. Changes in GABA synthesis or release may have a significant effect on normal brain function. Furthermore, The molecular interactions and pharmacological effects caused by drugs are extremely complex. This is due to the structural heterogeneity of the receptors, and the existence of multiple allosteric binding sites as well as a wide range of ligands that can bind to them. Notably, dysfunction of the GABAergic system contributes to the development of several diseases. Therefore, understanding the relationship between GABAA receptor deficits and CNS disorders thus has a significant impact on the discovery of disease pathogenesis and drug development. Conclusion To date, few reviews have discussed GABAA receptors in detail. Accordingly, this review aims to summarize the current understanding of the structural, physiological, and pharmacological properties of GABAARs, as well as shedding light on the most common associated disorders.
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Affiliation(s)
- Amr Ghit
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy. .,Department of Biotechnology, Institute of Graduate Studies and Research (IGSR), Alexandria University, Alexandria, Egypt.
| | - Dina Assal
- Department of Biotechnology, American University in Cairo (AUC), Cairo, Egypt
| | - Ahmed S Al-Shami
- Department of Biotechnology, Institute of Graduate Studies and Research (IGSR), Alexandria University, Alexandria, Egypt.,Department of Zoology, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Diaa Eldin E Hussein
- Animal Health Research Institute (AHRI), Agricultural Research Center (ARC), Port of Alexandria, Alexandria, Egypt
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Bojić MG, Todorović L, Santrač A, Mian MY, Sharmin D, Cook JM, Savić MM. Vasodilatory effects of a variety of positive allosteric modulators of GABA A receptors on rat thoracic aorta. Eur J Pharmacol 2021; 899:174023. [PMID: 33722589 DOI: 10.1016/j.ejphar.2021.174023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 02/18/2021] [Accepted: 03/10/2021] [Indexed: 01/06/2023]
Abstract
Different subtypes of GABAA (gamma-aminobutyric acid A) receptors, through their specific regional and cellular localization, are involved in the manifestation of various functions, both at the central and peripheral levels. We hypothesized that various non-neuronal GABAA receptors are expressed on blood vessels, through which positive allosteric modulators of GABAA receptors exhibit vasodilatory effects. This study involved two parts: one to determine the presence of α1-6 subunit GABAA receptor mRNAs in the rat thoracic aorta, and the other to determine the vasoactivity of the various selective and non-selective positive GABAA receptor modulators: zolpidem (α1-selective), XHe-III-074 (α4-selective), MP-III-022 (α5-selective), DK-I-56-1 (α6-selective), SH-I-048A and diazepam (non-selective). Reverse transcription-polymerase chain reaction (RT-PCR) analysis data demonstrated for the first time the expression of α1, α2, α3, α4 and α5 subunits in the rat thoracic aorta tissue. Tissue bath assays on isolated rat aortic rings revealed significant vasodilatory effects of diazepam, SH-I-048A, XHe-III-074, MP-III-022 and DK-I-56-1, all in terms of achieved relaxations (over 50% of relative tension decrease), as well as in terms of preventive effects on phenylephrine (PE) contraction. Diazepam was the most efficient ligand in the present study, while zolpidem showed the weakest vascular effects. In addition, diazepam-induced relaxations in the presence of antagonists PK11195 or bicuculline were significantly reduced (P < 0.001 and P < 0.05, respectively) at lower concentrations of diazepam (10-7 M and 3 × 10-7 M). The present work suggests that the observed vasoactivity is due to modulation of "vascular" GABAA receptors, which after further detailed research may provide a therapeutic target.
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Affiliation(s)
- Milica Gajić Bojić
- Center for Biomedical Research, Faculty of Medicine, University of Banja Luka, 16 Save Mrkalja St, 78000, Banja Luka, Republic of Srpska, Bosnia and Herzegovina
| | - Lidija Todorović
- Laboratory for Radiobiology and Molecular Genetics, Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Anja Santrač
- Department of Pharmacology, Faculty of Pharmacy, University of Belgrade, 450 Vojvode Stepe St, 11000, Belgrade, Serbia
| | - Md Yeunus Mian
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, 3210 N. Cramer St., Milwaukee, WI, 53201, USA
| | - Dishary Sharmin
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, 3210 N. Cramer St., Milwaukee, WI, 53201, USA
| | - James M Cook
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, 3210 N. Cramer St., Milwaukee, WI, 53201, USA
| | - Miroslav M Savić
- Department of Pharmacology, Faculty of Pharmacy, University of Belgrade, 450 Vojvode Stepe St, 11000, Belgrade, Serbia.
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Pavón-Romero GF, Serrano-Pérez NH, García-Sánchez L, Ramírez-Jiménez F, Terán LM. Neuroimmune Pathophysiology in Asthma. Front Cell Dev Biol 2021; 9:663535. [PMID: 34055794 PMCID: PMC8155297 DOI: 10.3389/fcell.2021.663535] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 04/15/2021] [Indexed: 12/26/2022] Open
Abstract
Asthma is a chronic inflammation of lower airway disease, characterized by bronchial hyperresponsiveness. Type I hypersensitivity underlies all atopic diseases including allergic asthma. However, the role of neurotransmitters (NT) and neuropeptides (NP) in this disease has been less explored in comparison with inflammatory mechanisms. Indeed, the airway epithelium contains pulmonary neuroendocrine cells filled with neurotransmitters (serotonin and GABA) and neuropeptides (substance P[SP], neurokinin A [NKA], vasoactive intestinal peptide [VIP], Calcitonin-gene related peptide [CGRP], and orphanins-[N/OFQ]), which are released after allergen exposure. Likewise, the autonomic airway fibers produce acetylcholine (ACh) and the neuropeptide Y(NPY). These NT/NP differ in their effects; SP, NKA, and serotonin exert pro-inflammatory effects, whereas VIP, N/OFQ, and GABA show anti-inflammatory activity. However, CGPR and ACh have dual effects. For example, the ACh-M3 axis induces goblet cell metaplasia, extracellular matrix deposition, and bronchoconstriction; the CGRP-RAMP1 axis enhances Th2 and Th9 responses; and the SP-NK1R axis promotes the synthesis of chemokines in eosinophils, mast cells, and neutrophils. In contrast, the ACh-α7nAChR axis in ILC2 diminishes the synthesis of TNF-α, IL-1, and IL-6, attenuating lung inflammation whereas, VIP-VPAC1, N/OFQ-NOP axes cause bronchodilation and anti-inflammatory effects. Some NT/NP as 5-HT and NKA could be used as biomarkers to monitor asthma patients. In fact, the asthma treatment based on inhaled corticosteroids and anticholinergics blocks M3 and TRPV1 receptors. Moreover, the administration of experimental agents such as NK1R/NK2R antagonists and exogenous VIP decrease inflammatory mediators, suggesting that regulating the effects of NT/NP represents a potential novel approach for the treatment of asthma.
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Affiliation(s)
| | | | | | | | - Luis M. Terán
- Department of Immunogenetics and Allergy, Instituto Nacional Enfermedades Respiratorias Ismael Cosío Villegas, Mexico City, Mexico
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12
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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 2020; 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] [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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13
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Knott EL, Leidenheimer NJ. A Targeted Bioinformatics Assessment of Adrenocortical Carcinoma Reveals Prognostic Implications of GABA System Gene Expression. Int J Mol Sci 2020; 21:ijms21228485. [PMID: 33187258 PMCID: PMC7697095 DOI: 10.3390/ijms21228485] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 11/05/2020] [Accepted: 11/09/2020] [Indexed: 12/12/2022] Open
Abstract
Adrenocortical carcinoma (ACC) is a rare but deadly cancer for which few treatments exist. Here, we have undertaken a targeted bioinformatics study of The Cancer Genome Atlas (TCGA) ACC dataset focusing on the 30 genes encoding the γ-aminobutyric acid (GABA) system—an under-studied, evolutionarily-conserved system that is an emerging potential player in cancer progression. Our analysis identified a subset of ACC patients whose tumors expressed a distinct GABA system transcriptome. Transcript levels of ABAT (encoding a key GABA shunt enzyme), were upregulated in over 40% of tumors, and this correlated with several favorable clinical outcomes including patient survival; while enrichment and ontology analysis implicated two cancer-related biological pathways involved in metastasis and immune response. The phenotype associated with ABAT upregulation revealed a potential metabolic heterogeneity among ACC tumors associated with enhanced mitochondrial metabolism. Furthermore, many GABAA receptor subunit-encoding transcripts were expressed, including two (GABRB2 and GABRD) prognostic for patient survival. Transcripts encoding GABAB receptor subunits and GABA transporters were also ubiquitously expressed. The GABA system transcriptome of ACC tumors is largely mirrored in the ACC NCI-H295R cell line, suggesting that this cell line may be appropriate for future functional studies investigating the role of the GABA system in ACC cell growth phenotypes and metabolism.
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14
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Patel BS, Ravix J, Pabelick C, Prakash YS. Class C GPCRs in the airway. Curr Opin Pharmacol 2020; 51:19-28. [PMID: 32375079 DOI: 10.1016/j.coph.2020.04.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 03/17/2020] [Accepted: 04/02/2020] [Indexed: 02/07/2023]
Abstract
Understanding and targeting of GPCRs remain a critical aspect of airway pharmacology and therapeutics for diseases such as asthma or COPD. Most attention has been on the large Class A GPCRs towards improved bronchodilation and blunting of remodeling. Better known in the central or peripheral nervous system, there is increasing evidence that Class C GPCRs which include metabotropic glutamate and GABA receptors, the calcium sensing receptor, sweet/umami taste receptors and a number of orphan receptors, can contribute to airway structure and function. In this review, we will summarize current state of knowledge regarding the pharmacology of Class C GPCRs, their expression and potential functions in the airways, and the application of pharmacological agents targeting this group in the context of airway diseases.
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Affiliation(s)
- Brijeshkumar S Patel
- Department of Anesthesiologyand Perioperative Medicine, Mayo Clinic, Rochester, MN, United States
| | - Jovanka Ravix
- Department of Anesthesiologyand Perioperative Medicine, Mayo Clinic, Rochester, MN, United States
| | - Christina Pabelick
- Department of Anesthesiologyand Perioperative Medicine, Mayo Clinic, Rochester, MN, United States; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
| | - Y S Prakash
- Department of Anesthesiologyand Perioperative Medicine, Mayo Clinic, Rochester, MN, United States; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States.
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15
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Crocetti L, Guerrini G. GABA A receptor subtype modulators in medicinal chemistry: an updated patent review (2014-present). Expert Opin Ther Pat 2020; 30:409-432. [PMID: 32200689 DOI: 10.1080/13543776.2020.1746764] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Introduction: Ligands at the benzodiazepine binding site of the GABAA receptor (GABAAR) act by modulating the effect of GABA (γ-aminobutyric acid). The benzodiazepine drugs are conventionally categorized as positive allosteric modulators enhancing the chloride ion current GABA-induced. In literature there are also reported ligands that act as negative allosteric modulators, reducing chloride ion current, and silent allosteric modulators not influencing the chloride ion flux.Areas covered: This review covers patents published from 2014 to present on ligands for the benzodiazepine binding site of the GABAARs. Patents filed from different companies and research groups report many compounds that may be used in the treatment/prevention of a large variety of diseases.Expert opinion: Since the discovery of the first benzodiazepine about 60 years have passed and about 50 years since the identification of their target, GABAA receptor. Even if benzodiazepines are the most popular anxiolytic drugs, the research in this field is still very active. From patents/application analysis arises that most of them claim methods for alleviating specific symptoms in different neurodegenerative diseases and their related memory deficits. Noteworthy is the presence of the α4- and α5-GABAA receptor subtype ligands as new pharmacological tools for airway hyperresponsiveness, inflammation diseases, and asthma.
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Affiliation(s)
- Letizia Crocetti
- NEUROFARBA, Pharmaceutical and Nutraceutical Section, University of Florence, Sesto Fiorentino, Italy
| | - Gabriella Guerrini
- NEUROFARBA, Pharmaceutical and Nutraceutical Section, University of Florence, Sesto Fiorentino, Italy
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16
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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: 0.8] [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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17
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Sharma J, Bhardwaj VK, Das P, Purohit R. Identification of naturally originated molecules as γ-aminobutyric acid receptor antagonist. J Biomol Struct Dyn 2020; 39:911-922. [DOI: 10.1080/07391102.2020.1720818] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Jatin Sharma
- Structural Bioinformatics Lab, CSIR-Institute of Himalayan Bioresource Technology (CSIR-IHBT), Palampur, Himachal Pradesh, India
- Biotechnology Division, CSIR-IHBT, Palampur, Himachal Pradesh, India
| | - Vijay Kumar Bhardwaj
- Structural Bioinformatics Lab, CSIR-Institute of Himalayan Bioresource Technology (CSIR-IHBT), Palampur, Himachal Pradesh, India
- Biotechnology Division, CSIR-IHBT, Palampur, Himachal Pradesh, India
- CSIR-IHBT Campus, Academy of Scientific & Innovative Research (AcSIR), Palampur, Himachal Pradesh, India
| | - Pralay Das
- CSIR-IHBT Campus, Academy of Scientific & Innovative Research (AcSIR), Palampur, Himachal Pradesh, India
- Natural Product Chemistry and Process Development, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh, India
| | - Rituraj Purohit
- Structural Bioinformatics Lab, CSIR-Institute of Himalayan Bioresource Technology (CSIR-IHBT), Palampur, Himachal Pradesh, India
- Biotechnology Division, CSIR-IHBT, Palampur, Himachal Pradesh, India
- CSIR-IHBT Campus, Academy of Scientific & Innovative Research (AcSIR), Palampur, Himachal Pradesh, India
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18
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Regulation of Airway Smooth Muscle Contraction in Health and Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1124:381-422. [PMID: 31183836 DOI: 10.1007/978-981-13-5895-1_16] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Airway smooth muscle (ASM) extends from the trachea throughout the bronchial tree to the terminal bronchioles. In utero, spontaneous phasic contraction of fetal ASM is critical for normal lung development by regulating intraluminal fluid movement, ASM differentiation, and release of key growth factors. In contrast, phasic contraction appears to be absent in the adult lung, and regulation of tonic contraction and airflow is under neuronal and humoral control. Accumulating evidence suggests that changes in ASM responsiveness contribute to the pathophysiology of lung diseases with lifelong health impacts.Functional assessments of fetal and adult ASM and airways have defined pharmacological responses and signaling pathways that drive airway contraction and relaxation. Studies using precision-cut lung slices, in which contraction of intrapulmonary airways and ASM calcium signaling can be assessed simultaneously in situ, have been particularly informative. These combined approaches have defined the relative importance of calcium entry into ASM and calcium release from intracellular stores as drivers of spontaneous phasic contraction in utero and excitation-contraction coupling.Increased contractility of ASM in asthma contributes to airway hyperresponsiveness. Studies using animal models and human ASM and airways have characterized inflammatory and other mechanisms underlying increased reactivity to contractile agonists and reduced bronchodilator efficacy of β2-adrenoceptor agonists in severe diseases. Novel bronchodilators and the application of bronchial thermoplasty to ablate increased ASM within asthmatic airways have the potential to overcome limitations of current therapies. These approaches may directly limit excessive airway contraction to improve outcomes for difficult-to-control asthma and other chronic lung diseases.
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19
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Emala CW. Bitter Taste Receptors: Taking a Bigger Bite of Airway Smooth Muscle Pathophysiology. Am J Respir Cell Mol Biol 2019; 60:492-493. [PMID: 30399322 PMCID: PMC6503616 DOI: 10.1165/rcmb.2018-0354ed] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Charles W Emala
- 1 Department of Anesthesiology Columbia University New York, New York
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20
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Bochud M, Ponte B, Pruijm M, Ackermann D, Guessous I, Ehret G, Escher G, Groessl M, Estoppey Younes S, d'Uscio CH, Burnier M, Martin PY, Pechère-Bertschi A, Vogt B, Dhayat NA. Urinary Sex Steroid and Glucocorticoid Hormones Are Associated With Muscle Mass and Strength in Healthy Adults. J Clin Endocrinol Metab 2019; 104:2195-2215. [PMID: 30690465 DOI: 10.1210/jc.2018-01942] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 01/18/2019] [Indexed: 02/04/2023]
Abstract
CONTEXT Sex steroid hormones exhibit anabolic effects whereas a deficiency engenders sarcopenia. Moreover, supraphysiological levels of glucocorticoids promote skeletal muscle atrophy, whereas physiologic levels of glucocorticoids may improve muscle performance. OBJECTIVE To study the relationship between both groups of steroid hormones at a physiological range with skeletal muscle mass and function in the general population. DESIGN Cross-sectional analysis of the associations between urinary excreted androgens, estrogens, glucocorticoids, and steroid hormone metabolite ratios with lean mass and handgrip strength in a population-based cohort. SETTING Three centers in Switzerland including 1128 participants. MEASURES Urinary steroid hormone metabolite excretion by gas chromatography-mass spectrometry, lean mass by bioimpedance analysis, and isometric handgrip strength by dynamometry. RESULTS For lean mass a strong positive association was found with 11β-OH-androsterone and with most glucocorticoids. Androsterone showed a positive association in middle-aged and older adults. Estriol showed a positive association only in men. For handgrip strength, strong positive associations with androgens were found in middle-aged and older adults, whereas positive associations were found with cortisol metabolites in young to middle-aged adults. CONCLUSIONS Sex steroids and glucocorticoids are strongly positively associated with skeletal muscle mass and strength in the upper limbs. The associations with muscle strength appear to be independent of muscle mass. Steroid hormones exert age-specific anabolic effects on lean mass and handgrip strength. Deficits in physical performance of aged muscles may be attenuated by androgens, whereas glucocorticoids in a physiological range increase skeletal muscle mass at all ages, as well as muscle strength in particular in younger adults.
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Affiliation(s)
- Murielle Bochud
- Institute of Social and Preventive Medicine, Lausanne University Hospital, Lausanne, Switzerland
| | - Belen Ponte
- Nephrology Service, Department of Specialties of Internal Medicine, University Hospital of Geneva, Geneva, Switzerland
| | - Menno Pruijm
- Nephrology Service, Lausanne University Hospital, Lausanne, Switzerland
| | - Daniel Ackermann
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Department of Clinical Research, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Idris Guessous
- Division of Primary Care Medicine, Geneva University Hospitals, Geneva, Switzerland
| | - Georg Ehret
- Cardiology Service, Department of Specialties of Internal Medicine, Geneva University Hospitals, Geneva, Switzerland
| | - Geneviève Escher
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Department of Clinical Research, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Michael Groessl
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Department of Clinical Research, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Sandrine Estoppey Younes
- Institute of Social and Preventive Medicine, Lausanne University Hospital, Lausanne, Switzerland
| | - Claudia H d'Uscio
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Department of Clinical Research, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Michel Burnier
- Nephrology Service, Lausanne University Hospital, Lausanne, Switzerland
| | - Pierre-Yves Martin
- Nephrology Service, Department of Specialties of Internal Medicine, University Hospital of Geneva, Geneva, Switzerland
| | - Antoinette Pechère-Bertschi
- Endocrinology Service, Department of Specialties of Internal Medicine, Geneva University Hospitals, Geneva, Switzerland
| | - Bruno Vogt
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Department of Clinical Research, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Nasser A Dhayat
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Department of Clinical Research, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
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21
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Pan S, Conaway S, Deshpande DA. Mitochondrial regulation of airway smooth muscle functions in health and pulmonary diseases. Arch Biochem Biophys 2019; 663:109-119. [PMID: 30629957 DOI: 10.1016/j.abb.2019.01.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 11/28/2018] [Accepted: 01/04/2019] [Indexed: 12/24/2022]
Abstract
Mitochondria are important for airway smooth muscle physiology due to their diverse yet interconnected roles in calcium handling, redox regulation, and cellular bioenergetics. Increasing evidence indicates that mitochondria dysfunction is intimately associated with airway diseases such as asthma, IPF and COPD. In these pathological conditions, increased mitochondrial ROS, altered bioenergetics profiles, and calcium mishandling contribute collectively to changes in cellular signaling, gene expression, and ultimately changes in airway smooth muscle contractile/proliferative properties. Therefore, understanding the basic features of airway smooth muscle mitochondria and their functional contribution to airway biology and pathology are key to developing novel therapeutics for airway diseases. This review summarizes the recent findings of airway smooth muscle mitochondria focusing on calcium homeostasis and redox regulation, two key determinants of physiological and pathological functions of airway smooth muscle.
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Affiliation(s)
- Shi Pan
- Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Stanley Conaway
- Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Deepak A Deshpande
- Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA.
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22
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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: 1.8] [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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23
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Forkuo GS, Nieman AN, Kodali R, Zahn NM, Li G, Rashid Roni MS, Stephen MR, Harris TW, Jahan R, Guthrie ML, Yu OB, Fisher JL, Yocum GT, Emala CW, Steeber DA, Stafford DC, Cook JM, Arnold LA. A Novel Orally Available Asthma Drug Candidate That Reduces Smooth Muscle Constriction and Inflammation by Targeting GABA A Receptors in the Lung. Mol Pharm 2018; 15:1766-1777. [PMID: 29578347 PMCID: PMC5954213 DOI: 10.1021/acs.molpharmaceut.7b01013] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We describe lead compound MIDD0301 for the oral treatment of asthma based on previously developed positive allosteric α5β3γ2 selective GABAA receptor (GABAAR) ligands. MIDD0301 relaxed airway smooth muscle at single micromolar concentrations as demonstrated with ex vivo guinea pig tracheal rings. MIDD0301 also attenuated airway hyperresponsiveness (AHR) in an ovalbumin murine model of asthma by oral administration. Reduced numbers of eosinophils and macrophages were observed in mouse bronchoalveolar lavage fluid without changing mucous metaplasia. Importantly, lung cytokine expression of IL-17A, IL-4, and TNF-α were reduced for MIDD0301-treated mice without changing antiinflammatory cytokine IL-10 levels. Automated patch clamp confirmed amplification of GABA induced current mediated by α1-3,5β3γ2 GABAARs in the presence of MIDD0301. Pharmacodynamically, transmembrane currents of ex vivo CD4+ T cells from asthmatic mice were potentiated by MIDD0301 in the presence of GABA. The number of CD4+ T cells observed in the lung of MIDD0301-treated mice were reduced by an oral treatment of 20 mg/kg b.i.d. for 5 days. A half-life of almost 14 h was demonstrated by pharmacokinetic studies (PK) with no adverse CNS effects when treated mice were subjected to sensorimotor studies using the rotarod. PK studies also confirmed very low brain distribution. In conclusion, MIDD0301 represents a safe and improved oral asthma drug candidate that relaxes airway smooth muscle and attenuates inflammation in the lung leading to a reduction of AHR at a dosage lower than earlier reported 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 53211, United States
| | - Amanda N. Nieman
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
| | - Revathi Kodali
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
| | - Nicolas M. Zahn
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
| | - Guanguan Li
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
| | - M. S. Rashid Roni
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
| | - Michael Rajesh Stephen
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
| | - Ted W. Harris
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
| | - Rajwana Jahan
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
| | - Margaret L. Guthrie
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
| | - Olivia B. Yu
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
| | - Janet L. Fisher
- Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, South Carolina 29208, United States
| | - Gene T. Yocum
- Department of Anesthesiology, Columbia University, New York, New York 10032, United States
| | - Charles W. Emala
- Department of Anesthesiology, Columbia University, New York, New York 10032, United States
| | - Douglas A. Steeber
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
| | - Douglas C. Stafford
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
| | - James M. Cook
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
| | - Leggy A. Arnold
- Department of Chemistry and Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
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24
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Li G, Stephen MR, Kodali R, Zahn NM, Poe MM, Tiruveedhula VVNPB, Huber AT, Schussman MK, Qualmann K, Panhans CM, Raddatz NJ, Baker DA, Prevot TD, Banasr M, Sibille E, Arnold LA, Cook JM. Synthesis of chiral GABA A receptor subtype selective ligands as potential agents to treat schizophrenia as well as depression. ARKIVOC 2018; 2018:158-182. [PMID: 32774192 PMCID: PMC7413308 DOI: 10.24820/ark.5550190.p010.460] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
A series of novel imidazobenzodiazepine analogs of the lead chiral ligand SH-053-2'F-S-CH3 (2), an α2/α3/α5 (Bz)GABA (A)ergic receptor subtype selective ligand, which reversed PCP-induced prepulse inhibition (PPI) of acoustic startle, were synthesized. These chiral (S)-CH3 ligands are targeted for the treatment of schizophrenia and depression. These new ligands were designed by modifying the liable ester functionality in 2 to improve the metabolic stability, cytotoxicity, and activity as compared to 2. Based on the data to date, the most promising ligands are the N-cyclopropyl amide GL-I-55 (8c) and the methyl bioisostere GL-I-65 (9a). The in vitro metabolic stability, cytotoxicity and in vivo locomotor effects are described in this report. Based on these results, 8c and 9a are the most promising for further in vivo pharmacology.
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Affiliation(s)
- Guanguan Li
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
| | - Michael R Stephen
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
| | - Revathi Kodali
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
| | - Nicolas M Zahn
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
| | - Michael M Poe
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
| | - V V N Phani Babu Tiruveedhula
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
| | - Alec T Huber
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
| | - Melissa K Schussman
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
| | - Krista Qualmann
- Department of Biomedical Science, Marquette University, Milwaukee, Wisconsin 53233, United States
| | - Cristina M Panhans
- Department of Biomedical Science, Marquette University, Milwaukee, Wisconsin 53233, United States
| | - Nicholas J Raddatz
- Department of Biomedical Science, Marquette University, Milwaukee, Wisconsin 53233, United States
| | - David A Baker
- Department of Biomedical Science, Marquette University, Milwaukee, Wisconsin 53233, United States
| | - Thomas D Prevot
- Campbell Family Mental Health Research Institute of CAMH, Toronto, Canada
| | - Mounira Banasr
- Campbell Family Mental Health Research Institute of CAMH, Toronto, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Canada
- Department of Psychiatry, University of Toronto, Toronto, Canada
| | - Etienne Sibille
- Campbell Family Mental Health Research Institute of CAMH, Toronto, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Canada
- Department of Psychiatry, University of Toronto, Toronto, Canada
| | - Leggy A Arnold
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
| | - James M Cook
- Department of Chemistry and Biochemistry, Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
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25
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Everington EA, Gibbard AG, Swinny JD, Seifi M. Molecular Characterization of GABA-A Receptor Subunit Diversity within Major Peripheral Organs and Their Plasticity in Response to Early Life Psychosocial Stress. Front Mol Neurosci 2018; 11:18. [PMID: 29467616 PMCID: PMC5807923 DOI: 10.3389/fnmol.2018.00018] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 01/12/2018] [Indexed: 11/13/2022] Open
Abstract
Gamma aminobutyric acid (GABA) subtype A receptors (GABAARs) are integral membrane ion channels composed of five individual proteins or subunits. Up to 19 different GABAAR subunits (α1–6, β1–3, γ1–3, δ, ε, θ, π, and ρ1–3) have been identified, resulting in anatomically, physiologically, and pharmacologically distinct multiple receptor subtypes, and therefore GABA-mediated inhibition, across the central nervous system (CNS). Additionally, GABAAR-modulating drugs are important tools in clinical medicine, although their use is limited by adverse effects. While significant advances have been made in terms of characterizing the GABAAR system within the brain, relatively less is known about the molecular phenotypes within the peripheral nervous system of major organ systems. This represents a potentially missed therapeutic opportunity in terms of utilizing or repurposing clinically available GABAAR drugs, as well as promising research compounds discarded due to their poor CNS penetrance, for the treatment of peripheral disorders. In addition, a broader understanding of the peripheral GABAAR subtype repertoires will contribute to the design of therapies which minimize peripheral side-effects when treating CNS disorders. We have recently provided a high resolution molecular and function characterization of the GABAARs within the enteric nervous system of the mouse colon. In this study, the aim was to determine the constituent GABAAR subunit expression profiles of the mouse bladder, heart, liver, kidney, lung, and stomach, using reverse transcription polymerase chain reaction and western blotting with brain as control. The data indicate that while some subunits are expressed widely across various organs (α3–5), others are restricted to individual organs (γ2, only stomach). Furthermore, we demonstrate complex organ-specific developmental expression plasticity of the transporters which determine the chloride gradient within cells, and therefore whether GABAAR activation has a depolarizing or hyperpolarizing effect. Finally, we demonstrate that prior exposure to early life psychosocial stress induces significant changes in peripheral GABAAR subunit expression and chloride transporters, in an organ- and subunit-specific manner. Collectively, the data demonstrate the molecular diversity of the peripheral GABAAR system and how this changes dynamically in response to life experience. This provides a molecular platform for functional analyses of the GABA–GABAAR system in health, and in diseases affecting various peripheral organs.
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Affiliation(s)
- Ethan A Everington
- Institute for Biomedical and Biomolecular Sciences and School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
| | - Adina G Gibbard
- Institute for Biomedical and Biomolecular Sciences and School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
| | - Jerome D Swinny
- Institute for Biomedical and Biomolecular Sciences and School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
| | - Mohsen Seifi
- Institute for Biomedical and Biomolecular Sciences and School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
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26
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Heffler E, Allegra A, Pioggia G, Picardi G, Musolino C, Gangemi S. MicroRNA Profiling in Asthma: Potential Biomarkers and Therapeutic Targets. Am J Respir Cell Mol Biol 2017; 57:642-650. [PMID: 28489455 DOI: 10.1165/rcmb.2016-0231tr] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Asthma is a heterogeneous chronic inflammatory disorder in which different endotypes contribute to define clinical inflammatory phenotypes. MicroRNAs (miRNAs) are a group of minute, endogenous 22-25 nt RNA elements that join to particular mRNAs to reduce translation and increase messenger RNA degradation. miRNAs operate in post-transcriptional control and regulate physiological and pathological processes in several illnesses. The purpose of this work is to review and discuss the current knowledge about the function of miRNAs in asthma, focusing particularly on their biological properties, pathophysiologic actions, and possible use as markers and treatments for asthma.
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Affiliation(s)
- Enrico Heffler
- 1 Personalized Medicine Asthma and Allergy Clinic, Humanitas Research Hospital, and.,2 Department of Biomedical Sciences, Humanitas University, Milan, Italy
| | - Alessandro Allegra
- 3 Division of Hematology, Department of General Surgery and Oncology, University of Messina
| | - Giovanni Pioggia
- 4 Institute of Applied Sciences and Intelligent Systems-Messina Unit, and
| | - Giuseppe Picardi
- 5 Respiratory Diseases and Allergy, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Caterina Musolino
- 3 Division of Hematology, Department of General Surgery and Oncology, University of Messina
| | - Sebastiano Gangemi
- 4 Institute of Applied Sciences and Intelligent Systems-Messina Unit, and.,6 School and Division of Allergy and Clinical Immunology, Department of Clinical and Experimental Medicine, University Hospital "G. Martino," Messina, Italy; and
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27
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Mikami M, Zhang Y, Danielsson J, Joell T, Yong HM, Townsend E, Khurana S, An SS, Emala CW. Impaired Relaxation of Airway Smooth Muscle in Mice Lacking the Actin-Binding Protein Gelsolin. Am J Respir Cell Mol Biol 2017; 56:628-636. [PMID: 28118027 DOI: 10.1165/rcmb.2016-0292oc] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Diverse classes of ligands have recently been discovered that relax airway smooth muscle (ASM) despite a transient increase in intracellular calcium concentrations ([Ca2+]i). However, the cellular mechanisms are not well understood. Gelsolin is a calcium-activated actin-severing and -capping protein found in many cell types, including ASM cells. Gelsolin also binds to phosphatidylinositol 4,5-bisphosphate, making this substrate less available for phospholipase Cβ-mediated hydrolysis to inositol triphosphate and diacylglycerol. We hypothesized that gelsolin plays a critical role in ASM relaxation and mechanistically accounts for relaxation by ligands that transiently increase [Ca2+]i. Isolated tracheal rings from gelsolin knockout (KO) mice showed impaired relaxation to both a β-agonist and chloroquine, a bitter taste receptor agonist, which relaxes ASM, despite inducing transiently increased [Ca2+]i. A single inhalation of methacholine increased lung resistance to a similar extent in wild-type and gelsolin KO mice, but the subsequent spontaneous relaxation was less in gelsolin KO mice. In ASM cells derived from gelsolin KO mice, serotonin-induced Gq-coupled activation increased both [Ca2+]i and inositol triphosphate synthesis to a greater extent compared to cells from wild-type mice, possibly due to the absence of gelsolin binding to phosphatidylinositol 4,5-bisphosphate. Single-cell analysis showed higher filamentous:globular actin ratio at baseline and slower cytoskeletal remodeling dynamics in gelsolin KO cells. Gelsolin KO ASM cells also showed an attenuated decrease in cell stiffness to chloroquine and flufenamic acid. These findings suggest that gelsolin plays a critical role in ASM relaxation and that activation of gelsolin may contribute to relaxation induced by ligands that relax ASM despite a transient increase in [Ca2+]i.
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Affiliation(s)
- Maya Mikami
- 1 Department of Anesthesiology, College of Physicians and Surgeons, Columbia University, New York, New York
| | - Yi Zhang
- 1 Department of Anesthesiology, College of Physicians and Surgeons, Columbia University, New York, New York
| | - Jennifer Danielsson
- 1 Department of Anesthesiology, College of Physicians and Surgeons, Columbia University, New York, New York
| | - Tiarra Joell
- 2 Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Hwan Mee Yong
- 2 Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Elizabeth Townsend
- 1 Department of Anesthesiology, College of Physicians and Surgeons, Columbia University, New York, New York
| | - Seema Khurana
- 3 Department of Biology and Biochemistry, University of Houston, Baylor College of Medicine, Houston, Texas; and
| | - Steven S An
- 2 Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,4 Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Charles W Emala
- 1 Department of Anesthesiology, College of Physicians and Surgeons, Columbia University, New York, New York
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28
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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: 3.1] [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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29
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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: 29] [Impact Index Per Article: 4.1] [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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30
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McGeachie MJ, Yates KP, Zhou X, Guo F, Sternberg AL, Van Natta ML, Wise RA, Szefler SJ, Sharma S, Kho AT, Cho MH, Croteau-Chonka DC, Castaldi PJ, Jain G, Sanyal A, Zhan Y, Lajoie BR, Dekker J, Stamatoyannopoulos J, Covar RA, Zeiger RS, Adkinson NF, Williams PV, Kelly HW, Grasemann H, Vonk JM, Koppelman GH, Postma DS, Raby BA, Houston I, Lu Q, Fuhlbrigge AL, Tantisira KG, Silverman EK, Tonascia J, Strunk RC, Weiss ST. Genetics and Genomics of Longitudinal Lung Function Patterns in Individuals with Asthma. Am J Respir Crit Care Med 2016; 194:1465-1474. [PMID: 27367781 PMCID: PMC5215031 DOI: 10.1164/rccm.201602-0250oc] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2016] [Accepted: 06/30/2016] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Patterns of longitudinal lung function growth and decline in childhood asthma have been shown to be important in determining risk for future respiratory ailments including chronic airway obstruction and chronic obstructive pulmonary disease. OBJECTIVES To determine the genetic underpinnings of lung function patterns in subjects with childhood asthma. METHODS We performed a genome-wide association study of 581 non-Hispanic white individuals with asthma that were previously classified by patterns of lung function growth and decline (normal growth, normal growth with early decline, reduced growth, and reduced growth with early decline). The strongest association was also measured in two additional cohorts: a small asthma cohort and a large chronic obstructive pulmonary disease metaanalysis cohort. Interaction between the genomic region encompassing the most strongly associated single-nucleotide polymorphism and nearby genes was assessed by two chromosome conformation capture assays. MEASUREMENTS AND MAIN RESULTS An intergenic single-nucleotide polymorphism (rs4445257) on chromosome 8 was strongly associated with the normal growth with early decline pattern compared with all other pattern groups (P = 6.7 × 10-9; odds ratio, 2.8; 95% confidence interval, 2.0-4.0); replication analysis suggested this variant had opposite effects in normal growth with early decline and reduced growth with early decline pattern groups. Chromosome conformation capture experiments indicated a chromatin interaction between rs4445257 and the promoter of the distal CSMD3 gene. CONCLUSIONS Early decline in lung function after normal growth is associated with a genetic polymorphism that may also protect against early decline in reduced growth groups. Clinical trial registered with www.clinicaltrials.gov (NCT00000575).
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Affiliation(s)
- Michael J. McGeachie
- Channing Division of Network Medicine and
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | | | - Xiaobo Zhou
- Channing Division of Network Medicine and
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | - Feng Guo
- Channing Division of Network Medicine and
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | | | | | - Robert A. Wise
- School of Medicine, Johns Hopkins University, Baltimore, Maryland
| | - Stanley J. Szefler
- National Jewish Health and Research Center, Denver, Colorado
- Children's Hospital Colorado and
| | - Sunita Sharma
- Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado, Denver, Colorado
| | - Alvin T. Kho
- Channing Division of Network Medicine and
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
- Boston Children’s Hospital, Boston, Massachusetts
| | - Michael H. Cho
- Channing Division of Network Medicine and
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | - Damien C. Croteau-Chonka
- Channing Division of Network Medicine and
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | - Peter J. Castaldi
- Channing Division of Network Medicine and
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | - Gaurav Jain
- Program in Systems Biology, Department of Biochemistry and Molecular Pharmacology, and
| | - Amartya Sanyal
- Program in Systems Biology, Department of Biochemistry and Molecular Pharmacology, and
- School of Biological Sciences, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - Ye Zhan
- Program in Systems Biology, Department of Biochemistry and Molecular Pharmacology, and
| | - Bryan R. Lajoie
- Program in Systems Biology, Department of Biochemistry and Molecular Pharmacology, and
| | - Job Dekker
- Howard Hughes Medical Institute, Program in Systems Biology, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts
| | | | - Ronina A. Covar
- National Jewish Health and Research Center, Denver, Colorado
- Children's Hospital Colorado and
- University of Colorado, Denver, Colorado
| | - Robert S. Zeiger
- Department of Pediatrics, University of California at San Diego, La Jolla, California
- Kaiser Permanente Southern California Region, San Diego, California
| | | | - Paul V. Williams
- ASTHMA, Inc., Clinical Research Center and Northwest Asthma & Allergy Center, Seattle, Washington
| | - H. William Kelly
- University of New Mexico Health Sciences Center, Albuquerque, New Mexico
| | - Hartmut Grasemann
- Division of Respiratory Medicine, Department of Pediatrics, The Hospital for Sick Children and University of Toronto, Toronto, Canada
| | | | - Gerard H. Koppelman
- Department of Pediatric Pulmonology and Pediatric Allergology, Beatrix Children’s Hospital, and
| | - Dirkje S. Postma
- Department of Pulmonology, University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD, Groningen, the Netherlands
| | - Benjamin A. Raby
- Channing Division of Network Medicine and
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | - Isaac Houston
- Channing Division of Network Medicine and
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | - Quan Lu
- Program in Molecular and Integrative Physiological Sciences, Departments of Environmental Health and Genetics & Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts; and
| | - Anne L. Fuhlbrigge
- Channing Division of Network Medicine and
- Division of Pulmonary and Critical Care Medicine, Brigham and Women’s Hospital, Boston, Massachusetts
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | - Kelan G. Tantisira
- Channing Division of Network Medicine and
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | - Edwin K. Silverman
- Channing Division of Network Medicine and
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | | | - Robert C. Strunk
- Division of Allergy, Immunology, and Pulmonary Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Scott T. Weiss
- Channing Division of Network Medicine and
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
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31
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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: 1.9] [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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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: 99] [Impact Index Per Article: 12.4] [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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33
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Yocum GT, Gallos G, Zhang Y, Jahan R, Stephen MR, Varagic Z, Puthenkalam R, Ernst M, Cook JM, Emala CW. Targeting the γ-Aminobutyric Acid A Receptor α4 Subunit in Airway Smooth Muscle to Alleviate Bronchoconstriction. Am J Respir Cell Mol Biol 2016; 54:546-53. [PMID: 26405827 DOI: 10.1165/rcmb.2015-0176oc] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We previously demonstrated that airway smooth muscle (ASM) cells express γ-aminobutyric acid A receptors (GABA(A)Rs), and that GABA(A)R agonists acutely relax ASM. Among the GABA(A)R α subunits, human ASM cells express only α4 and α5, providing the opportunity for selective pharmacologic targeting. Novel GABA(A)R-positive allosteric modulators designed for enhanced α4/α6 subunit selectivity were synthesized using iterative computational analyses (CMD-45 and XHe-III-74). Studies using oocyte heterologous expression systems confirmed that CMD-45 and XHe-III-74 led to significantly greater augmentation of currents induced by a 3% maximal effective concentration (EC3) of GABA [EC3]-induced currents in oocytes expressing α4 or α6 subunits (along with β3 and γ2) compared with other α subunits. CMD-45 and XHe-III-74 also led to greater ex vivo relaxation of contracted wild-type mouse tracheal rings compared with tracheal rings from GABA(A)R α4 subunit (Gabra4) knockout mice. Furthermore, CMD-45 and XHe-III-74 significantly relaxed precontracted human ASM ex vivo, and, at a low concentration, both ligands led to a significant leftward shift in albuterol-mediated ASM relaxation. In vivo, inhaled XHe-III-74 reduced respiratory system resistance in an asthmatic mouse model. Pretreatment of human ASM cells with CMD-45 and XHe-III-74 inhibited histamine-induced increases in intracellular calcium concentrations in vitro, an effect that was lost when calcium was omitted from the extracellular buffer, suggesting that inhibition of calcium influx due to alterations in plasma membrane potential may play a role in the mechanism of ASM relaxation. Selective targeting of the GABA(A)R α4 subunit with inhaled ligands may be a novel therapeutic pathway to treat bronchoconstriction, while avoiding sedative central nervous system effects, which are largely mediated by α1-3 subunit-containing GABA(A)Rs in the brain.
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Affiliation(s)
- Gene T Yocum
- 1 Department of Anesthesiology, College of Physicians and Surgeons, Columbia University, New York, New York
| | - George Gallos
- 1 Department of Anesthesiology, College of Physicians and Surgeons, Columbia University, New York, New York
| | - Yi Zhang
- 1 Department of Anesthesiology, College of Physicians and Surgeons, Columbia University, New York, New York
| | - Rajwana Jahan
- 2 Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin; and
| | - Michael Rajesh Stephen
- 2 Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin; and
| | - Zdravko Varagic
- 3 Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Roshan Puthenkalam
- 3 Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Margot Ernst
- 3 Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - James M Cook
- 2 Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin; and
| | - Charles W Emala
- 1 Department of Anesthesiology, College of Physicians and Surgeons, Columbia University, New York, New York
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34
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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: 5.0] [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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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: 3.0] [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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36
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Nieman AN, Forkuo GS, Guthrie ML, Yuan NY, Yu OB, Kodali R, Zahn NM, Jahan R, Stephen MR, Poe MM, Hartzler B, Emala CW, Cook JM, Arnold LA. Targeting the immune system with subtype-selective GABAA receptor modulator to alleviate asthma symptoms. THE JOURNAL OF IMMUNOLOGY 2016. [DOI: 10.4049/jimmunol.196.supp.192.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Abstract
Inflammation is one of the main characteristics of asthma in addition to mucus metaplasia and airway hyperresponsiveness due to muscle constriction. Therefore, current asthma treatments include corticosteroids, which are associated with many negative side effects1. Recently, small molecule modulators of the γ-aminobutyric acid receptor (GABAAR) have been shown to reduce inflammation and induce airway smooth muscle relaxation2,3. GABAARs are expressed in the neurons to moderate neuronal firing. However other cell types have distinct arrangements of GABAAR subtypes as well, which can be targeted with subtype-selective GABAAR modulators. Our study hypothesizes that compounds targeting GABAARs bearing the α4 subunit will predominantly target airway smooth muscle cells and immune cells. We have developed two subtype-selective GABAAR modulators, Xhe-III-74EE and Xhe-III-74A. Investigations with T cells showed reduced IL-2 levels for treated cells. In addition, both compounds reduced cellular rapid cytoplasmic calcium release upon activation. In vivo studies showed that XHE-III-74A was able to reduce eosinophilia in an ovalbumin sensitized and challenged (Ova S/C) model.
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Affiliation(s)
- Amanda N Nieman
- 1Univ. of Wisconsin, Milwaukee
- 2Milwaukee Inst. for Drug Discovery
| | - Gloria S. Forkuo
- 1Univ. of Wisconsin, Milwaukee
- 2Milwaukee Inst. for Drug Discovery
| | | | - Nina Y. Yuan
- 1Univ. of Wisconsin, Milwaukee
- 2Milwaukee Inst. for Drug Discovery
| | - Olivia B. Yu
- 1Univ. of Wisconsin, Milwaukee
- 2Milwaukee Inst. for Drug Discovery
| | - Revathi Kodali
- 1Univ. of Wisconsin, Milwaukee
- 2Milwaukee Inst. for Drug Discovery
| | - Nicolas M. Zahn
- 1Univ. of Wisconsin, Milwaukee
- 2Milwaukee Inst. for Drug Discovery
| | - Rajwana Jahan
- 1Univ. of Wisconsin, Milwaukee
- 2Milwaukee Inst. for Drug Discovery
| | | | - Michael M. Poe
- 1Univ. of Wisconsin, Milwaukee
- 2Milwaukee Inst. for Drug Discovery
| | | | | | - James M. Cook
- 1Univ. of Wisconsin, Milwaukee
- 2Milwaukee Inst. for Drug Discovery
| | - Leggy A. Arnold
- 1Univ. of Wisconsin, Milwaukee
- 2Milwaukee Inst. for Drug Discovery
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37
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Danielsson J, Zaidi S, Kim B, Funayama H, Yim PD, Xu D, Worgall TS, Gallos G, Emala CW. Airway Epithelial Cell Release of GABA is Regulated by Protein Kinase A. Lung 2016; 194:401-8. [PMID: 26989055 DOI: 10.1007/s00408-016-9867-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 03/09/2016] [Indexed: 01/05/2023]
Abstract
INTRODUCTION γ-amino butyric acid (GABA) is not only the major inhibitory neurotransmitter in the central nervous system (CNS), but it also plays an important role in the lung, mediating airway smooth muscle relaxation and mucus production. As kinases such as protein kinase A (PKA) are known to regulate the release and reuptake of GABA in the CNS by GABA transporters, we hypothesized that β-agonists would affect GABA release from airway epithelial cells through activation of PKA. METHODS C57/BL6 mice received a pretreatment of a β-agonist or vehicle (PBS), followed by methacholine or PBS. Bronchoalveolar lavage (BAL) was collected and the amount of GABA was quantified using HPLC mass spectrometry. For in vitro studies, cultured BEAS-2B human airway epithelial cells were loaded with (3)H-GABA. (3)H-GABA released was measured during activation and inhibition of PKA and tyrosine kinase signaling pathways. RESULTS β-agonist pretreatment prior to methacholine challenge attenuated in vivo GABA release in mouse BAL and (3)H-GABA release from depolarized BEAS-2B cells. GABA release was also decreased in BEAS-2B cells by increases in cAMP but not by Epac or tyrosine kinase activation. CONCLUSION β-agonists decrease GABA release from airway epithelium through the activation of cAMP and PKA. This has important therapeutic implications as β-agonists and GABA are important mediators of both mucus production and airway smooth muscle tone.
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Affiliation(s)
- Jennifer Danielsson
- Department of Anesthesiology, Columbia University, 630 W 168th St., P&S Box 46, New York, NY, 10032, USA.
| | - Sarah Zaidi
- Department of Pediatrics, Columbia University, New York, NY, 10032, USA
| | - Benjamin Kim
- Department of Pathology and Cell Biology, Columbia University, New York, NY, 10032, USA
| | - Hiromi Funayama
- Department of Anesthesiology, Columbia University, 630 W 168th St., P&S Box 46, New York, NY, 10032, USA
- Department of Pediatric Dentistry, Tsurumi University School of Dental Medicine, Yokohama, Japan
| | - Peter D Yim
- Department of Anesthesiology, Columbia University, 630 W 168th St., P&S Box 46, New York, NY, 10032, USA
| | - Dingbang Xu
- Department of Anesthesiology, Columbia University, 630 W 168th St., P&S Box 46, New York, NY, 10032, USA
| | - Tilla S Worgall
- Department of Pathology and Cell Biology, Columbia University, New York, NY, 10032, USA
| | - George Gallos
- Department of Anesthesiology, Columbia University, 630 W 168th St., P&S Box 46, New York, NY, 10032, USA
| | - Charles W Emala
- Department of Anesthesiology, Columbia University, 630 W 168th St., P&S Box 46, New York, NY, 10032, USA
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38
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A Review of the Updated Pharmacophore for the Alpha 5 GABA(A) Benzodiazepine Receptor Model. INTERNATIONAL JOURNAL OF MEDICINAL CHEMISTRY 2015; 2015:430248. [PMID: 26682068 PMCID: PMC4657098 DOI: 10.1155/2015/430248] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 06/16/2015] [Accepted: 07/02/2015] [Indexed: 12/22/2022]
Abstract
An updated model of the GABA(A) benzodiazepine receptor pharmacophore of the α5-BzR/GABA(A) subtype has been constructed prompted by the synthesis of subtype selective ligands in light of the recent developments in both ligand synthesis, behavioral studies, and molecular modeling studies of the binding site itself. A number of BzR/GABA(A) α5 subtype selective compounds were synthesized, notably α5-subtype selective inverse agonist PWZ-029 (1) which is active in enhancing cognition in both rodents and primates. In addition, a chiral positive allosteric modulator (PAM), SH-053-2′F-R-CH3 (2), has been shown to reverse the deleterious effects in the MAM-model of schizophrenia as well as alleviate constriction in airway smooth muscle. Presented here is an updated model of the pharmacophore for α5β2γ2 Bz/GABA(A) receptors, including a rendering of PWZ-029 docked within the α5-binding pocket showing specific interactions of the molecule with the receptor. Differences in the included volume as compared to α1β2γ2, α2β2γ2, and α3β2γ2 will be illustrated for clarity. These new models enhance the ability to understand structural characteristics of ligands which act as agonists, antagonists, or inverse agonists at the Bz BS of GABA(A) receptors.
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Jin S, Merchant ML, Ritzenthaler JD, McLeish KR, Lederer ED, Torres-Gonzalez E, Fraig M, Barati MT, Lentsch AB, Roman J, Klein JB, Rane MJ. Baclofen, a GABABR agonist, ameliorates immune-complex mediated acute lung injury by modulating pro-inflammatory mediators. PLoS One 2015; 10:e0121637. [PMID: 25848767 PMCID: PMC4388838 DOI: 10.1371/journal.pone.0121637] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 02/12/2015] [Indexed: 11/22/2022] Open
Abstract
Immune-complexes play an important role in the inflammatory diseases of the lung. Neutrophil activation mediates immune-complex (IC) deposition-induced acute lung injury (ALI). Components of gamma amino butyric acid (GABA) signaling, including GABA B receptor 2 (GABABR2), GAD65/67 and the GABA transporter, are present in the lungs and in the neutrophils. However, the role of pulmonary GABABR activation in the context of neutrophil-mediated ALI has not been determined. Thus, the objective of the current study was to determine whether administration of a GABABR agonist, baclofen would ameliorate or exacerbate ALI. We hypothesized that baclofen would regulate IC-induced ALI by preserving pulmonary GABABR expression. Rats were subjected to sham injury or IC-induced ALI and two hours later rats were treated intratracheally with saline or 1 mg/kg baclofen for 2 additional hours and sacrificed. ALI was assessed by vascular leakage, histology, TUNEL, and lung caspase-3 cleavage. ALI increased total protein, tumor necrosis factor α (TNF-α and interleukin-1 receptor associated protein (IL-1R AcP), in the bronchoalveolar lavage fluid (BALF). Moreover, ALI decreased lung GABABR2 expression, increased phospho-p38 MAPK, promoted IκB degradation and increased neutrophil influx in the lung. Administration of baclofen, after initiation of ALI, restored GABABR expression, which was inhibited in the presence of a GABABR antagonist, CGP52432. Baclofen administration activated pulmonary phospho-ERK and inhibited p38 MAPK phosphorylation and IκB degradation. Additionally, baclofen significantly inhibited pro-inflammatory TNF-α and IL-1βAcP release and promoted BAL neutrophil apoptosis. Protective effects of baclofen treatment on ALI were possibly mediated by inhibition of TNF-α- and IL-1β-mediated inflammatory signaling. Interestingly, GABABR2 expression was regulated in the type II pneumocytes in lung tissue sections from lung injured patients, further suggesting a physiological role for GABABR2 in the repair process of lung damage. GABABR2 agonists may play a potential therapeutic role in ALI.
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Affiliation(s)
- Shunying Jin
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
| | - Michael L. Merchant
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
| | - Jeffrey D. Ritzenthaler
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
| | - Kenneth R. McLeish
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
- Department of Biochemistry and Molecular Biology, University of Louisville, Louisville, Kentucky, United States of America
- Robley Rex VA Medical Center, Zorn Avenue, Louisville, Kentucky, United States of America
| | - Eleanor D. Lederer
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
- Robley Rex VA Medical Center, Zorn Avenue, Louisville, Kentucky, United States of America
- Department of Physiology, University of Louisville, Louisville, Kentucky, United States of America
| | - Edilson Torres-Gonzalez
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
| | - Mostafa Fraig
- Department of Pathology, University of Louisville, Louisville, Kentucky, United States of America
| | - Michelle T. Barati
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
| | - Alex B. Lentsch
- Department of Surgery, University of Cincinnati, Cincinnati, OH, United States of America
| | - Jesse Roman
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
- Robley Rex VA Medical Center, Zorn Avenue, Louisville, Kentucky, United States of America
| | - Jon B. Klein
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
- Department of Biochemistry and Molecular Biology, University of Louisville, Louisville, Kentucky, United States of America
- Robley Rex VA Medical Center, Zorn Avenue, Louisville, Kentucky, United States of America
| | - Madhavi J. Rane
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
- Department of Biochemistry and Molecular Biology, University of Louisville, Louisville, Kentucky, United States of America
- * E-mail:
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Gallos G, Yocum GT, Siviski ME, Yim PD, Fu XW, Poe MM, Cook JM, Harrison N, Perez-Zoghbi J, Emala CW. Selective targeting of the α5-subunit of GABAA receptors relaxes airway smooth muscle and inhibits cellular calcium handling. Am J Physiol Lung Cell Mol Physiol 2015; 308:L931-42. [PMID: 25659897 DOI: 10.1152/ajplung.00107.2014] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 02/05/2015] [Indexed: 12/23/2022] Open
Abstract
The clinical need for novel bronchodilators for the treatment of bronchoconstrictive diseases remains a major medical issue. Modulation of airway smooth muscle (ASM) chloride via GABAA receptor activation to achieve relaxation of precontracted ASM represents a potentially beneficial therapeutic option. Since human ASM GABAA receptors express only the α4- and α5-subunits, there is an opportunity to selectively target ASM GABAA receptors to improve drug efficacy and minimize side effects. Recently, a novel compound (R)-ethyl8-ethynyl-6-(2-fluorophenyl)-4-methyl-4H-benzo[f]imidazo[1,5-a][1,4] diazepine-3-carboxylate (SH-053-2'F-R-CH3) with allosteric selectivity for α5-subunit containing GABAA receptors has become available. We questioned whether this novel GABAA α5-selective ligand relaxes ASM and affects intracellular calcium concentration ([Ca(2+)]i) regulation. Immunohistochemical staining localized the GABAA α5-subunit to human ASM. The selective GABAA α5 ligand SH-053-2'F-R-CH3 relaxes precontracted intact ASM; increases GABA-activated chloride currents in human ASM cells in voltage-clamp electrophysiology studies; and attenuates bradykinin-induced increases in [Ca(2+)]i, store-operated Ca(2+) entry, and methacholine-induced Ca(2+) oscillations in peripheral murine lung slices. In conclusion, selective subunit targeting of endogenous α5-subunit containing GABAA receptors on ASM may represent a novel therapeutic option to treat severe bronchospasm.
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Affiliation(s)
- George Gallos
- Department of Anesthesiology, College of Physicians and Surgeons of Columbia University, New York, New York;
| | - Gene T Yocum
- Department of Anesthesiology, College of Physicians and Surgeons of Columbia University, New York, New York
| | - Matthew E Siviski
- Department of Anesthesiology, College of Physicians and Surgeons of Columbia University, New York, New York
| | - Peter D Yim
- Department of Anesthesiology, College of Physicians and Surgeons of Columbia University, New York, New York
| | - Xiao Wen Fu
- Department of Anesthesiology, College of Physicians and Surgeons of Columbia University, New York, New York
| | - Michael M Poe
- Department of Chemistry, University of Wisconsin, Milwaukee, Wisconsin; and
| | - James M Cook
- Department of Chemistry, University of Wisconsin, Milwaukee, Wisconsin; and
| | - Neil Harrison
- Department of Anesthesiology, College of Physicians and Surgeons of Columbia University, New York, New York
| | - Jose Perez-Zoghbi
- Department of Cell Physiology and Molecular Biophysics; and Texas Tech University Health Sciences Center, Lubbock, Texas
| | - Charles W Emala
- Department of Anesthesiology, College of Physicians and Surgeons of Columbia University, New York, New York
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41
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Bulley S, Jaggar JH. Cl⁻ channels in smooth muscle cells. Pflugers Arch 2014; 466:861-72. [PMID: 24077695 DOI: 10.1007/s00424-013-1357-2] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 09/09/2013] [Accepted: 09/09/2013] [Indexed: 10/26/2022]
Abstract
In smooth muscle cells (SMCs), the intracellular chloride ion (Cl−) concentration is high due to accumulation by Cl−/HCO3− exchange and Na+–K+–Cl− cotransportation. The equilibrium potential for Cl− (ECl) is more positive than physiological membrane potentials (Em), with Cl− efflux inducing membrane depolarization. Early studies used electrophysiology and nonspecific antagonists to study the physiological relevance of Cl− channels in SMCs. More recent reports have incorporated molecular biological approaches to identify and determine the functional significance of several different Cl− channels. Both "classic" and cGMP-dependent calcium (Ca2+)-activated (ClCa) channels and volume-sensitive Cl− channels are present, with TMEM16A/ANO1, bestrophins, and ClC-3, respectively, proposed as molecular candidates for these channels. The cystic fibrosis transmembrane conductance regulator (CFTR) has also been described in SMCs. This review will focus on discussing recent progress made in identifying each of these Cl− channels in SMCs, their physiological functions, and contribution to diseases that modify contraction, apoptosis, and cell proliferation.
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Fuchs A, Baur R, Schoeder C, Sigel E, Müller CE. Structural analogues of the natural products magnolol and honokiol as potent allosteric potentiators of GABA(A) receptors. Bioorg Med Chem 2014; 22:6908-17. [PMID: 25456080 DOI: 10.1016/j.bmc.2014.10.027] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 10/13/2014] [Accepted: 10/15/2014] [Indexed: 11/27/2022]
Abstract
Biphenylic compounds related to the natural products magnolol and 4'-O-methylhonokiol were synthesized, evaluated and optimized as positive allosteric modulators (PAMs) of GABA(A) receptors. The most efficacious compounds were the magnolol analog 5-ethyl-5'-hexylbiphenyl-2,2'-diol (45) and the honokiol analogs 4'-methoxy-5-propylbiphenyl-2-ol (61), 5-butyl-4'-methoxybiphenyl-2-ol (62) and 5-hexyl-4'-methoxybiphenyl-2-ol (64), which showed a most powerful potentiation of GABA-induced currents (up to 20-fold at a GABA concentration of 3μM). They were found not to interfere with the allosteric sites occupied by known allosteric modulators, such as benzodiazepines and N-arachidonoylglycerol. These new PAMs will be useful as pharmacological tools and may have therapeutic potential for mono-therapy, or in combination, for example, with GABA(A) receptor agonists.
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Affiliation(s)
- Alexander Fuchs
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Roland Baur
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
| | - Clara Schoeder
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Erwin Sigel
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
| | - Christa E Müller
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany; Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland.
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Prakash YS. Airway smooth muscle in airway reactivity and remodeling: what have we learned? Am J Physiol Lung Cell Mol Physiol 2013; 305:L912-33. [PMID: 24142517 PMCID: PMC3882535 DOI: 10.1152/ajplung.00259.2013] [Citation(s) in RCA: 159] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 10/12/2013] [Indexed: 12/12/2022] Open
Abstract
It is now established that airway smooth muscle (ASM) has roles in determining airway structure and function, well beyond that as the major contractile element. Indeed, changes in ASM function are central to the manifestation of allergic, inflammatory, and fibrotic airway diseases in both children and adults, as well as to airway responses to local and environmental exposures. Emerging evidence points to novel signaling mechanisms within ASM cells of different species that serve to control diverse features, including 1) [Ca(2+)]i contractility and relaxation, 2) cell proliferation and apoptosis, 3) production and modulation of extracellular components, and 4) release of pro- vs. anti-inflammatory mediators and factors that regulate immunity as well as the function of other airway cell types, such as epithelium, fibroblasts, and nerves. These diverse effects of ASM "activity" result in modulation of bronchoconstriction vs. bronchodilation relevant to airway hyperresponsiveness, airway thickening, and fibrosis that influence compliance. This perspective highlights recent discoveries that reveal the central role of ASM in this regard and helps set the stage for future research toward understanding the pathways regulating ASM and, in turn, the influence of ASM on airway structure and function. Such exploration is key to development of novel therapeutic strategies that influence the pathophysiology of diseases such as asthma, chronic obstructive pulmonary disease, and pulmonary fibrosis.
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Affiliation(s)
- Y S Prakash
- Dept. of Anesthesiology, Mayo Clinic, 4-184 W Jos SMH, 200 First St. SW, Rochester, MN 55905.
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Levänen B, Bhakta NR, Paredes PT, Barbeau R, Hiltbrunner S, Pollack JL, Sköld CM, Svartengren M, Grunewald J, Gabrielsson S, Eklund A, Larsson BM, Woodruff PG, Erle DJ, Wheelock ÅM. Altered microRNA profiles in bronchoalveolar lavage fluid exosomes in asthmatic patients. J Allergy Clin Immunol 2013; 131:894-903. [PMID: 23333113 PMCID: PMC4013392 DOI: 10.1016/j.jaci.2012.11.039] [Citation(s) in RCA: 196] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 11/18/2012] [Accepted: 11/21/2012] [Indexed: 12/21/2022]
Abstract
BACKGROUND Asthma is characterized by increased airway narrowing in response to nonspecific stimuli. The disorder is influenced by both environmental and genetic factors. Exosomes are nanosized vesicles of endosomal origin released from inflammatory and epithelial cells that have been implicated in asthma. In this study we characterized the microRNA (miRNA) content of exosomes in healthy control subjects and patients with mild intermittent asthma both at unprovoked baseline and in response to environmental challenge. OBJECTIVE To investigate alterations in bronchoalveolar lavage fluid (BALF) exosomal miRNA profiles due to asthma, and following subway air exposure. METHODS Exosomes were isolated from BALF from healthy control subjects (n = 10) and patients with mild intermittent asthma (n = 10) after subway and control exposures. Exosomal RNA was analyzed by using microarrays containing probes for 894 human miRNAs, and selected findings were validated with quantitative RT-PCR. Results were analyzed by using multivariate modeling. RESULTS The presence of miRNAs was confirmed in exosomes from BALF of both asthmatic patients and healthy control subjects. Significant differences in BALF exosomal miRNA was detected for 24 miRNAs with a subset of 16 miRNAs, including members of the let-7 and miRNA-200 families, providing robust classification of patients with mild nonsymptomatic asthma from healthy subjects with 72% cross-validated predictive power (Q(2) = 0.72). In contrast, subway exposure did not cause any significant alterations in miRNA profiles. CONCLUSION These studies demonstrate substantial differences in exosomal miRNA profiles between healthy subjects and patients with unprovoked, mild, stable asthma. These changes might be important in the inflammatory response leading to bronchial hyperresponsiveness and asthma.
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Affiliation(s)
- Bettina Levänen
- Respiratory Medicine Unit, Department of Medicine, and the Center for Molecular Medicine, Karolinska Institutet, Stockholm
| | - Nirav R. Bhakta
- Division of Pulmonary and Critical Care, Department of Medicine and Cardiovascular Research Institute, University of California–San Francisco
| | | | | | - Stefanie Hiltbrunner
- Translational Immunology Unit, Department of Medicine, Karolinska Institutet, Stockholm
| | | | - C. Magnus Sköld
- Respiratory Medicine Unit, Department of Medicine, and the Center for Molecular Medicine, Karolinska Institutet, Stockholm
| | - Magnus Svartengren
- Division of Occupational and Environmental Medicine, Department of Public Health Sciences, Karolinska Institutet, Stockholm
| | - Johan Grunewald
- Respiratory Medicine Unit, Department of Medicine, and the Center for Molecular Medicine, Karolinska Institutet, Stockholm
| | - Susanne Gabrielsson
- Translational Immunology Unit, Department of Medicine, Karolinska Institutet, Stockholm
| | - Anders Eklund
- Respiratory Medicine Unit, Department of Medicine, and the Center for Molecular Medicine, Karolinska Institutet, Stockholm
| | - Britt-Marie Larsson
- Division of Occupational and Environmental Medicine, Department of Public Health Sciences, Karolinska Institutet, Stockholm
| | - Prescott G. Woodruff
- Division of Pulmonary and Critical Care, Department of Medicine and Cardiovascular Research Institute, University of California–San Francisco
| | - David J. Erle
- Division of Pulmonary and Critical Care, Department of Medicine and Cardiovascular Research Institute, University of California–San Francisco
- Lung Biology Center, University of California–San Francisco
| | - Åsa M. Wheelock
- Respiratory Medicine Unit, Department of Medicine, and the Center for Molecular Medicine, Karolinska Institutet, Stockholm
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Zhang CH, Li Y, Zhao W, Lifshitz LM, Li H, Harfe BD, Zhu MS, ZhuGe R. The transmembrane protein 16A Ca(2+)-activated Cl- channel in airway smooth muscle contributes to airway hyperresponsiveness. Am J Respir Crit Care Med 2012; 187:374-81. [PMID: 23239156 DOI: 10.1164/rccm.201207-1303oc] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
RATIONALE Asthma is a chronic inflammatory disorder with a characteristic of airway hyperresponsiveness (AHR). Ca(2+)-activated Cl(-) [Cl((Ca))] channels are inferred to be involved in AHR, yet their molecular nature and the cell type they act within to mediate this response remain unknown. OBJECTIVES Transmembrane protein 16A (TMEM16A) and TMEM16B are Cl((Ca)) channels, and activation of Cl((Ca)) channels in airway smooth muscle (ASM) contributes to agonist-induced airway contraction. We hypothesized that Tmem16a and/or Tmem16b encode Cl((Ca)) channels in ASM and mediate AHR. METHODS We assessed the expression of the TMEM16 family, and the effects of niflumic acid and benzbromarone on AHR and airway contraction, in an ovalbumin-sensitized mouse model of chronic asthma. We also cloned TMEM16A from ASM and examined the Cl(-) currents it produced in HEK293 cells. We further studied the impacts of TMEM16A deletion on Ca(2+) agonist-induced cell shortening, and on Cl((Ca)) currents activated by Ca(2+) sparks (localized, short-lived Ca(2+) transients due to the opening of ryanodine receptors) in mouse ASM cells. MEASUREMENTS AND MAIN RESULTS TMEM16A, but not TMEM16B, is expressed in ASM cells and its expression in these cells is up-regulated in ovalbumin-sensitized mice. Niflumic acid and benzbromarone prevent AHR and contraction evoked by methacholine in ovalbumin-sensitized mice. TMEM16A produces Cl((Ca)) currents with kinetics similar to native Cl((Ca)) currents. TMEM16A deletion renders Ca(2+) sparks unable to activate Cl((Ca)) currents, and weakens caffeine- and methacholine-induced cell shortening. CONCLUSIONS Tmem16a encodes Cl((Ca)) channels in ASM and contributes to Ca(2+) agonist-induced contraction. In addition, up-regulation of TMEM16A and its augmented activation contribute to AHR in an ovalbumin-sensitized mouse model of chronic asthma. TMEM16A may represent a potential therapeutic target for asthma.
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Affiliation(s)
- Cheng-Hai Zhang
- Model Animal Research Center, Nanjing University, Nanjing, China
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Chintagari NR, Liu L. GABA receptor ameliorates ventilator-induced lung injury in rats by improving alveolar fluid clearance. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2012; 16:R55. [PMID: 22480160 PMCID: PMC3681384 DOI: 10.1186/cc11298] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Revised: 03/05/2012] [Accepted: 04/05/2012] [Indexed: 12/18/2022]
Abstract
Introduction Mechanical ventilators are increasingly used in critical care units. However, they can cause lung injury, including pulmonary edema. Our previous studies indicated that γ-aminobutyric acid (GABA) receptors are involved in alveolar-fluid homeostasis. The present study investigated the role of GABA receptors in ventilator-induced lung injury. Methods Adult female Sprague-Dawley rats were subjected to high-tidal-volume ventilation of 40 ml/kg body weight for 1 hour, and lung injuries were assessed. Results High-tidal-volume ventilation resulted in lung injury, as indicated by an increase in total protein in bronchoalveolar fluid, wet-to-dry ratio (indication of pulmonary edema), and Evans Blue dye extravasation (indication of vascular damage). Intratracheal administration of GABA before ventilation significantly reduced the wet-to-dry ratio. Further, histopathologic analysis indicated that GABA reduced ventilator-induced lung injury and apoptosis. GABA-mediated reduction was effectively blocked by the GABAA-receptor antagonist, bicuculline. The GABA-mediated effect was not due to the vascular damage, because no differences in Evans Blue dye extravasation were noted. However, the decrease in alveolar fluid clearance by high-tidal-volume ventilation was partly prevented by GABA, which was blocked by bicuculline. Conclusions These results suggest that GABA reduces pulmonary edema induced by high-tidal-volume ventilation via its effects on alveolar fluid clearance and apoptosis.
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Affiliation(s)
- Narendranath Reddy Chintagari
- Lundberg-Kienlen Lung Biology and Toxicology Laboratory, Department of Physiological Sciences, Oklahoma State University, 264 McElroy Hall, Stillwater, OK 74078, USA
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Gallos G, Townsend E, Yim P, Virag L, Zhang Y, Xu D, Bacchetta M, Emala CW. Airway epithelium is a predominant source of endogenous airway GABA and contributes to relaxation of airway smooth muscle tone. Am J Physiol Lung Cell Mol Physiol 2012. [PMID: 23204068 DOI: 10.1152/ajplung.00274.2012] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Chronic obstructive pulmonary disease and asthma are characterized by hyperreactive airway responses that predispose patients to episodes of acute airway constriction. Recent studies suggest a complex paradigm of GABAergic signaling in airways that involves GABA-mediated relaxation of airway smooth muscle. However, the cellular source of airway GABA and mechanisms regulating its release remain unknown. We questioned whether epithelium is a major source of GABA in the airway and whether the absence of epithelium-derived GABA contributes to greater airway smooth muscle force. Messenger RNA encoding glutamic acid decarboxylase (GAD) 65/67 was quantitatively measured in human airway epithelium and smooth muscle. HPLC quantified GABA levels in guinea pig tracheal ring segments under basal or stimulated conditions with or without epithelium. The role of endogenous GABA in the maintenance of an acetylcholine contraction in human airway and guinea pig airway smooth muscle was assessed in organ baths. A 37.5-fold greater amount of mRNA encoding GAD 67 was detected in human epithelium vs. airway smooth muscle cells. HPLC confirmed that guinea pig airways with intact epithelium have a higher constitutive elution of GABA under basal or KCl-depolarized conditions compared with epithelium-denuded airway rings. Inhibition of GABA transporters significantly suppressed KCl-mediated release of GABA from epithelium-intact airways, but tetrodotoxin was without effect. The presence of intact epithelium had a significant GABAergic-mediated prorelaxant effect on the maintenance of contractile tone. Airway epithelium is a predominant cellular source of endogenous GABA in the airway and contributes significant prorelaxant GABA effects on airway smooth muscle force.
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Affiliation(s)
- George Gallos
- Department of Anesthesiology, College of Physicians and Surgeons, Columbia University, 622 W. 168 St., P&S Box 46, New York, NY 10032, USA.
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Abstract
The GABA(A) receptors are the major inhibitory neurotransmitter receptors in mammalian brain. Each isoform consists of five homologous or identical subunits surrounding a central chloride ion-selective channel gated by GABA. How many isoforms of the receptor exist is far from clear. GABA(A) receptors located in the postsynaptic membrane mediate neuronal inhibition that occurs in the millisecond time range; those located in the extrasynaptic membrane respond to ambient GABA and confer long-term inhibition. GABA(A) receptors are responsive to a wide variety of drugs, e.g. benzodiazepines, which are often used for their sedative/hypnotic and anxiolytic effects.
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Affiliation(s)
- Erwin Sigel
- Institute of Biochemistry and Molecular Medicine, University of Bern, CH-3012 Bern, Switzerland.
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Can we find better bronchodilators to relieve asthma symptoms? J Allergy (Cairo) 2012; 2012:321949. [PMID: 23091500 PMCID: PMC3467860 DOI: 10.1155/2012/321949] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Accepted: 09/05/2012] [Indexed: 01/27/2023] Open
Abstract
Bronchodilators are the first line therapy during acute asthmatic exacerbations to reverse airway obstruction primarily by relaxing airway smooth muscle. Only three categories of bronchodilators exist in clinical practice: β-adrenergic agonists, anticholinergics, and methylxanthines. Each of these categories have specific drugs dating back to the early 20th century, raising the question of whether or not we can find better bronchodilators. While caffeine, theophylline, atropine, and epinephrine were the first generations of therapeutics in each of these drug classes, there is no question that improvements have been made in the bronchodilators in each of these classes. In the following editorial, we will briefly describe new classes of potential bronchodilators including: novel PDE inhibitors, natural phytotherapeutics, bitter taste receptor ligands, and chloride channel modulators, which have the potential to be used alone or in combination with existing bronchodilators to reverse acute airway obstruction in the future.
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