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O'Brien JB, Roman DL. Novel treatments for chronic pain: moving beyond opioids. Transl Res 2021; 234:1-19. [PMID: 33727192 DOI: 10.1016/j.trsl.2021.03.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 03/06/2021] [Accepted: 03/08/2021] [Indexed: 02/06/2023]
Abstract
It is essential that safe and effective treatment options be available to patients suffering from chronic pain. The emergence of an opioid epidemic has shaped public opinions and created stigmas surrounding the use of opioids for the management of pain. This reality, coupled with high risk of adverse effects from chronic opioid use, has led chronic pain patients and their healthcare providers to utilize nonopioid treatment approaches. In this review, we will explore a number of cellular reorganizations that are associated with the development and progression of chronic pain. We will also discuss the safety and efficacy of opioid and nonopioid treatment options for chronic pain. Finally, we will review the evidence for adenylyl cyclase type 1 (AC1) as a novel target for the treatment of chronic pain.
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Affiliation(s)
- Joseph B O'Brien
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, Iowa
| | - David L Roman
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, Iowa; Iowa Neuroscience Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa.
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2
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The chilling of adenylyl cyclase 9 and its translational potential. Cell Signal 2020; 70:109589. [PMID: 32105777 DOI: 10.1016/j.cellsig.2020.109589] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 02/21/2020] [Accepted: 02/23/2020] [Indexed: 12/26/2022]
Abstract
A recent break-through paper has revealed for the first time the high-resolution, three-dimensional structure of a mammalian trans-membrane adenylyl cyclase (tmAC) obtained by cryo-electronmicroscopy (cryo-EM). Reporting the structure of adenylyl cyclase 9 (AC9) in complex with activated Gsα, the cryo-EM study revealed that AC9 has three functionally interlinked, yet structurally distinct domains. The array of the twelve transmembrane helices is connected to the cytosolic catalytic core by two helical segments that are stabilized through the formation of a parallel coiled-coil. Surprisingly, in the presence of Gsα, the isoform-specific carboxyl-terminal tail of AC9 occludes the forskolin- as well as the active substrate-sites, resulting in marked autoinhibition of the enzyme. As AC9 has the lowest primary sequence homology with the eight further mammalian tmAC paralogues, it appears to be the best candidate for selective pharmacologic targeting. This is now closer to reality as the structural insight provided by the cryo-EM study indicates that all of the three structural domains are potential targets for bioactive agents. The present paper summarizes for molecular physiologists and pharmacologists what is known about the biological role of AC9, considers the potential modes of physiologic regulation, as well as pharmacologic targeting on the basis of the high-resolution cryo-EM structure. The translational potential of AC9 is considered upon highlighting the current state of genome-wide association screens, and the corresponding experimental evidence. Overall, whilst the high- resolution structure presents unique opportunities for the full understanding of the control of AC9, the data on the biological role of the enzyme and its translational potential are far from complete, and require extensive further study.
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Simpson J, Pálvölgyi A, Antoni FA. Direct stimulation of adenylyl cyclase 9 by the fungicide imidazole miconazole. Naunyn Schmiedebergs Arch Pharmacol 2019; 392:497-504. [PMID: 30607468 DOI: 10.1007/s00210-018-01610-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 12/21/2018] [Indexed: 10/27/2022]
Abstract
In mammals, nine genes encode trans-membrane adenylyl cyclase (tmAC) isoforms that synthesize the intracellular messenger compound cAMP from ATP. As cAMP is produced in virtually all types of cell, isoform-selective modulators of tmAC would have major research and therapeutic potential. This study investigated the effects of fungicide imidazoles previously shown to suppress cAMP production in various tissues on the activities of tmAC isoforms AC1, 2, or 9 stably expressed in human embryonic kidney 293 cells. Intact cells, as well as crude membranes, were exposed to various imidazoles or known stimulators of tmAC and the ensuing changes in the production of cAMP analyzed. In crude membranes, the activity of AC9 in the presence of GDP-β-S was enhanced by miconazole with an EC50 of ~ 8 μM, while AC1 and AC2 were inhibited with an IC50 of ~ 20 μM. Clotrimazole (10-100 μM) was an inhibitor of all the ACs tested. Substrate saturation analysis indicated that miconazole increased the Vmax of AC9 by 3-fold while having no effect on the Km. In intact cells, the effect of miconazole on cAMP production through AC9 was additive with that of isoproterenol. The stimulation of cAMP production by miconazole was inhibited by Ca2+, and this could be prevented by the calcineurin blocker FK506. In sum, activation of AC9 by miconazole is through a mechanism distinct from that of forskolin, activated G proteins, or the COOH-terminal mediated autoinhibition. However, it is subject to the AC9 isoform-specific inhibition by Ca2+/calcineurin. Differential modulation of mammalian tmAC paralogs appears to be achievable by an imidazole with phenylated side chains. Optimization of the lead compound and exploration of the underlying mechanism(s) of action in more detail could exploit this further.
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Affiliation(s)
- James Simpson
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, Scotland, EH8 9XD, UK
| | - Adrienn Pálvölgyi
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - Ferenc A Antoni
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, Scotland, EH8 9XD, UK. .,Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary.
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Dessauer CW, Watts VJ, Ostrom RS, Conti M, Dove S, Seifert R. International Union of Basic and Clinical Pharmacology. CI. Structures and Small Molecule Modulators of Mammalian Adenylyl Cyclases. Pharmacol Rev 2017; 69:93-139. [PMID: 28255005 PMCID: PMC5394921 DOI: 10.1124/pr.116.013078] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Adenylyl cyclases (ACs) generate the second messenger cAMP from ATP. Mammalian cells express nine transmembrane AC (mAC) isoforms (AC1-9) and a soluble AC (sAC, also referred to as AC10). This review will largely focus on mACs. mACs are activated by the G-protein Gαs and regulated by multiple mechanisms. mACs are differentially expressed in tissues and regulate numerous and diverse cell functions. mACs localize in distinct membrane compartments and form signaling complexes. sAC is activated by bicarbonate with physiologic roles first described in testis. Crystal structures of the catalytic core of a hybrid mAC and sAC are available. These structures provide detailed insights into the catalytic mechanism and constitute the basis for the development of isoform-selective activators and inhibitors. Although potent competitive and noncompetitive mAC inhibitors are available, it is challenging to obtain compounds with high isoform selectivity due to the conservation of the catalytic core. Accordingly, caution must be exerted with the interpretation of intact-cell studies. The development of isoform-selective activators, the plant diterpene forskolin being the starting compound, has been equally challenging. There is no known endogenous ligand for the forskolin binding site. Recently, development of selective sAC inhibitors was reported. An emerging field is the association of AC gene polymorphisms with human diseases. For example, mutations in the AC5 gene (ADCY5) cause hyperkinetic extrapyramidal motor disorders. Overall, in contrast to the guanylyl cyclase field, our understanding of the (patho)physiology of AC isoforms and the development of clinically useful drugs targeting ACs is still in its infancy.
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Affiliation(s)
- Carmen W Dessauer
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Sciences Center at Houston, Houston, Texas (C.W.D.); Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (V.J.W.); Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.); Center for Reproductive Sciences, University of California San Francisco, San Francisco, California (M.C.); Institute of Pharmacy, University of Regensburg, Regensburg, Germany (S.D.); and Institute of Pharmacology, Hannover Medical School, Hannover, Germany (R.S.)
| | - Val J Watts
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Sciences Center at Houston, Houston, Texas (C.W.D.); Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (V.J.W.); Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.); Center for Reproductive Sciences, University of California San Francisco, San Francisco, California (M.C.); Institute of Pharmacy, University of Regensburg, Regensburg, Germany (S.D.); and Institute of Pharmacology, Hannover Medical School, Hannover, Germany (R.S.)
| | - Rennolds S Ostrom
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Sciences Center at Houston, Houston, Texas (C.W.D.); Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (V.J.W.); Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.); Center for Reproductive Sciences, University of California San Francisco, San Francisco, California (M.C.); Institute of Pharmacy, University of Regensburg, Regensburg, Germany (S.D.); and Institute of Pharmacology, Hannover Medical School, Hannover, Germany (R.S.)
| | - Marco Conti
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Sciences Center at Houston, Houston, Texas (C.W.D.); Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (V.J.W.); Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.); Center for Reproductive Sciences, University of California San Francisco, San Francisco, California (M.C.); Institute of Pharmacy, University of Regensburg, Regensburg, Germany (S.D.); and Institute of Pharmacology, Hannover Medical School, Hannover, Germany (R.S.)
| | - Stefan Dove
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Sciences Center at Houston, Houston, Texas (C.W.D.); Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (V.J.W.); Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.); Center for Reproductive Sciences, University of California San Francisco, San Francisco, California (M.C.); Institute of Pharmacy, University of Regensburg, Regensburg, Germany (S.D.); and Institute of Pharmacology, Hannover Medical School, Hannover, Germany (R.S.)
| | - Roland Seifert
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Sciences Center at Houston, Houston, Texas (C.W.D.); Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana (V.J.W.); Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.); Center for Reproductive Sciences, University of California San Francisco, San Francisco, California (M.C.); Institute of Pharmacy, University of Regensburg, Regensburg, Germany (S.D.); and Institute of Pharmacology, Hannover Medical School, Hannover, Germany (R.S.)
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5
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Boularan C, Gales C. Cardiac cAMP: production, hydrolysis, modulation and detection. Front Pharmacol 2015; 6:203. [PMID: 26483685 PMCID: PMC4589651 DOI: 10.3389/fphar.2015.00203] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 09/03/2015] [Indexed: 01/04/2023] Open
Abstract
Cyclic adenosine 3′,5′-monophosphate (cAMP) modulates a broad range of biological processes including the regulation of cardiac myocyte contractile function where it constitutes the main second messenger for β-adrenergic receptors' signaling to fulfill positive chronotropic, inotropic and lusitropic effects. A growing number of studies pinpoint the role of spatial organization of the cAMP signaling as an essential mechanism to regulate cAMP outcomes in cardiac physiology. Here, we will briefly discuss the complexity of cAMP synthesis and degradation in the cardiac context, describe the way to detect it and review the main pharmacological arsenal to modulate its availability.
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Affiliation(s)
- Cédric Boularan
- Institut des Maladies Métaboliques et Cardiovasculaires, Institut National de la Santé et de la Recherche Médicale, U1048, Université Toulouse III Paul Sabatier Toulouse, France
| | - Céline Gales
- Institut des Maladies Métaboliques et Cardiovasculaires, Institut National de la Santé et de la Recherche Médicale, U1048, Université Toulouse III Paul Sabatier Toulouse, France
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Effects of 39 Compounds on Calmodulin-Regulated Adenylyl Cyclases AC1 and Bacillus anthracis Edema Factor. PLoS One 2015; 10:e0124017. [PMID: 25946093 PMCID: PMC4422518 DOI: 10.1371/journal.pone.0124017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2014] [Accepted: 03/09/2015] [Indexed: 12/29/2022] Open
Abstract
Adenylyl cyclases (ACs) catalyze the conversion of ATP into the second messenger cAMP. Membranous AC1 (AC1) is involved in processes of memory and learning and in muscle pain. The AC toxin edema factor (EF) of Bacillus anthracis is involved in the development of anthrax. Both ACs are stimulated by the eukaryotic Ca2+-sensor calmodulin (CaM). The CaM-AC interaction could constitute a potential target to enhance or impair the AC activity of AC1 and EF to intervene in above (patho)physiological mechanisms. Thus, we analyzed the impact of 39 compounds including typical CaM-inhibitors, an anticonvulsant, an anticholinergic, antidepressants, antipsychotics and Ca2+-antagonists on CaM-stimulated catalytic activity of AC1 and EF. Compounds were tested at 10 μM, i.e., a concentration that can be reached therapeutically for certain antidepressants and antipsychotics. Calmidazolium chloride decreased CaM-stimulated AC1 activity moderately by about 30%. In contrast, CaM-stimulated EF activity was abrogated by calmidazolium chloride and additionally decreased by chlorpromazine, felodipine, penfluridol and trifluoperazine by about 20–40%. The activity of both ACs was decreased by calmidazolium chloride in the presence and absence of CaM. Thus, CaM-stimulated AC1 activity is more insensitive to inhibition by small molecules than CaM-stimulated EF activity. Inhibition of AC1 and EF by calmidazolium chloride is largely mediated via a CaM-independent allosteric mechanism.
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Steegborn C. Structure, mechanism, and regulation of soluble adenylyl cyclases — similarities and differences to transmembrane adenylyl cyclases. Biochim Biophys Acta Mol Basis Dis 2014; 1842:2535-47. [DOI: 10.1016/j.bbadis.2014.08.012] [Citation(s) in RCA: 142] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 08/19/2014] [Accepted: 08/26/2014] [Indexed: 12/14/2022]
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Towards selective inhibitors of adenylyl cyclase toxin from Bordetella pertussis. Trends Microbiol 2012; 20:343-51. [PMID: 22578665 DOI: 10.1016/j.tim.2012.04.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2012] [Revised: 03/27/2012] [Accepted: 04/04/2012] [Indexed: 12/19/2022]
Abstract
Whooping cough is a very important medical problem that requires novel approaches for treatment. The disease is caused by Bordetella pertussis, with the calmodulin (CaM)-activated adenylyl cyclase (AC) toxin (also known as CyaA) being a major virulence factor. Hence, CyaA inhibitors could constitute novel therapeutics, but it has been difficult to develop potent drugs with high selectivity over mammalian membranous ACs (mACs). Recent studies have shown that bis-anthraniloyl-substituted nucleoside 5'-triphosphates are potent and selective CyaA inhibitors. In addition, the interaction of CyaA with CaM is very different from the interaction of membranous mAC1 with CaM. Accordingly, compounds that interfere with the CyaA-CaM interaction may constitute a novel class of drugs against whooping cough.
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Schuler D, Lübker C, Lushington GH, Tang WJ, Shen Y, Richter M, Seifert R. Interactions of Bordetella pertussis adenylyl cyclase toxin CyaA with calmodulin mutants and calmodulin antagonists: comparison with membranous adenylyl cyclase I. Biochem Pharmacol 2012; 83:839-848. [PMID: 22265637 DOI: 10.1016/j.bcp.2012.01.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Revised: 01/03/2012] [Accepted: 01/04/2012] [Indexed: 01/12/2023]
Abstract
The adenylyl cyclase (AC) toxin CyaA from Bordetella pertussis constitutes an important virulence factor for the pathogenesis of whooping cough. CyaA is activated by calmodulin (CaM) and compromises host defense by excessive cAMP production. Hence, pharmacological modulation of the CyaA/CaM interaction could constitute a promising approach to treat whooping cough, provided that interactions of endogenous effector proteins with CaM are not affected. As a first step toward this ambitious goal we examined the interactions of CyaA with wild-type CaM and four CaM mutants in which most methionine residues were replaced by leucine residues and studied the effects of the CaM antagonists calmidazolium, trifluoperazine and N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7). CyaA/CaM interaction was monitored by CaM-dependent fluorescence resonance energy transfer (FRET) between tryptophan residues in CyaA and 2'-(N-methylanthraniloyl)-3'-deoxy-adenosine 5'-triphosphate and catalytic activity. Comparison of the concentration/response curves of CaM and CaM mutants for FRET and catalysis revealed differences, suggesting a two-step activation mechanism of CyaA by CaM. Even in the absence of CaM, calmidazolium inhibited catalysis, and it did so according to a biphasic function. Trifluoperazine and W-7 did not inhibit FRET or catalysis. In contrast to CyaA, some CaM mutants were more efficacious than CaM at activating membranous AC isoform 1. The slope of CyaA activation by CaM was much steeper than of AC1 activation. Collectively, the two-step activation mechanism of CyaA by CaM offers opportunities for pharmacological intervention. The failure of classic CaM inhibitors to interfere with CyaA/CaM interactions and the different interactions of CaM mutants with CyaA and AC1 point to unique CyaA/CaM interactions.
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Affiliation(s)
- Dominik Schuler
- Institute of Pharmacology, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany
| | - Carolin Lübker
- Institute of Pharmacology, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany
| | - Gerald H Lushington
- Molecular Graphics and Modeling Laboratory, The University of Kansas, KS 66045, USA
| | - Wei-Jen Tang
- Ben May Department of Cancer Research, The University of Chicago, Chicago, IL 60637, USA
| | - Yuequan Shen
- College of Life Sciences, Nankai University, 300071 Tianjin, People's Republic of China
| | - Mark Richter
- Department of Molecular Biosciences, The University of Kansas, Lawrence, KS 66045, USA
| | - Roland Seifert
- Institute of Pharmacology, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany
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Seifert R, Lushington GH, Mou TC, Gille A, Sprang SR. Inhibitors of membranous adenylyl cyclases. Trends Pharmacol Sci 2011; 33:64-78. [PMID: 22100304 DOI: 10.1016/j.tips.2011.10.006] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Revised: 10/18/2011] [Accepted: 10/19/2011] [Indexed: 12/11/2022]
Abstract
Membranous adenylyl cyclases (mACs) constitute a family of nine isoforms with different expression patterns. Studies with mAC gene knockout mice provide evidence for the notion that AC isoforms play distinct (patho)physiological roles. Consequently, there is substantial interest in the development of isoform-selective mAC inhibitors. Here, we review the current literature on mAC inhibitors. Structurally diverse inhibitors targeting the catalytic site and allosteric sites (e.g. the diterpene site) have been identified. The catalytic site of mACs accommodates both purine and pyrimidine nucleotides, with a hydrophobic pocket constituting a major affinity-conferring domain for substituents at the 2'- and 3'-O-ribosyl position of nucleotides. BODIPY-forskolin stimulates ACs 1 and 5 but inhibits AC2. However, so far, no inhibitor has been examined at all mAC isoforms, and data obtained with mAC inhibitors in intact cells have not always been interpreted cautiously enough. Future strategies for the development of the mAC inhibitor field are discussed critically.
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Affiliation(s)
- Roland Seifert
- Institute of Pharmacology, Medical School of Hannover, Carl-Neuberg-Strasse 1, D-30625 Hannover, Germany.
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Fuss N, Mujagic S, Erber J, Wachten S, Baumann A. Biochemical properties of heterologously expressed and native adenylyl cyclases from the honeybee brain (Apis mellifera L.). INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2010; 40:573-580. [PMID: 20685336 DOI: 10.1016/j.ibmb.2010.05.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2010] [Revised: 05/06/2010] [Accepted: 05/20/2010] [Indexed: 05/29/2023]
Abstract
Cyclic AMP is an important intracellular signaling molecule participating e.g. in sensory signal transduction, cardiac myocyte regulation, learning and memory. The formation of cAMP is catalyzed by adenylyl cyclases. A variety of factors can modulate the properties of these enzymes and lead to dynamic changes of the intracellular cAMP concentration. Here we determined the tissue distribution of a recently cloned adenylyl cyclase (AmAC3) in honeybee brain. The protein is present in all neuropils. Intensive immunoreactivity was found in parts of the proto- and deutocerebrum and in the suboesophageal ganglion. Biochemical and pharmacological properties of AmAC3 and of native adenylyl cyclases in subregions of the honeybee brain were examined. Values for half-maximal activation with NKH477 were in the low micromolar range with 10.2 μM for AmAC3 and 3.6-8.1 μM for native enzymes. Biosynthesis of cAMP was specifically blocked by P-site inhibitors. Adenylyl cyclases in antennal lobes and AmAC3 share the inhibitory profile with 2',5'dd3'ATP>3'AMP>2'deoxyadenosine. In addition to P-site inhibitors AmAC3 activity was impaired by Ca(2+)/calmodulin. The results suggest that AmAC3 is a likely candidate to fulfill an integrative role in sensory, motor and higher-order information processing in the honeybee brain.
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Affiliation(s)
- Nadine Fuss
- Institut für Strukturbiologie and Biophysik 1, Forschungszentrum Jülich, D-52425 Jülich, Germany
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12
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Bartos JA, Ulrich JD, Li H, Beazely MA, Chen Y, MacDonald JF, Hell JW. Postsynaptic clustering and activation of Pyk2 by PSD-95. J Neurosci 2010; 30:449-63. [PMID: 20071509 PMCID: PMC2822408 DOI: 10.1523/jneurosci.4992-08.2010] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2008] [Revised: 11/01/2009] [Accepted: 11/04/2009] [Indexed: 12/24/2022] Open
Abstract
The tyrosine kinase Pyk2 plays a unique role in intracellular signal transduction by linking Ca(2+) influx to tyrosine phosphorylation, but the molecular mechanism of Pyk2 activation is unknown. We report that Pyk2 oligomerization by antibodies in vitro or overexpression of PSD-95 in PC6-3 cells induces trans-autophosphorylation of Tyr402, the first step in Pyk2 activation. In neurons, Ca(2+) influx through NMDA-type glutamate receptors causes postsynaptic clustering and autophosphorylation of endogenous Pyk2 via Ca(2+)- and calmodulin-stimulated binding to PSD-95. Accordingly, Ca(2+) influx promotes oligomerization and thereby autoactivation of Pyk2 by stimulating its interaction with PSD-95. We show that this mechanism of Pyk2 activation is critical for long-term potentiation in the hippocampus CA1 region, which is thought to underlie learning and memory.
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Affiliation(s)
- Jason A. Bartos
- Department of Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242-1109
| | - Jason D. Ulrich
- Department of Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242-1109
| | - Hongbin Li
- Department of Physiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada, and
| | - Michael A. Beazely
- Department of Physiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada, and
| | - Yucui Chen
- Department of Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242-1109
| | - John F. MacDonald
- Department of Physiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada, and
- Robarts Research Institute, University of Western Ontario, London, Ontario N6A 5K8, Canada
| | - Johannes W. Hell
- Department of Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242-1109
- Department of Pharmacology, University of California, Davis, Davis, California 95616-8636
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James LR, Griffiths CH, Garthwaite J, Bellamy TC. Inhibition of nitric oxide-activated guanylyl cyclase by calmodulin antagonists. Br J Pharmacol 2009; 158:1454-64. [PMID: 19845679 DOI: 10.1111/j.1476-5381.2009.00416.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND AND PURPOSE Nitric oxide (NO) controls numerous physiological processes by activation of its receptor, guanylyl cyclase (sGC), leading to the accumulation of 3'-5' cyclic guanosine monophosphate (cGMP). Ca(2+)-calmodulin (CaM) regulates both NO synthesis by NO synthase and cGMP hydrolysis by phosphodiesterase-1. We report that, unexpectedly, the CaM antagonists, calmidazolium, phenoxybenzamine and trifluoperazine, also inhibited cGMP accumulation in cerebellar cells evoked by an exogenous NO donor, with IC(50) values of 11, 80 and 180 microM respectively. Here we sought to elucidate the underlying mechanism(s). EXPERIMENTAL APPROACH We used cerebellar cell suspensions to determine the influence of CaM antagonists on all steps of the NO-cGMP pathway. Homogenized tissue and purified enzyme were used to test effects of calmidazolium on sGC activity. KEY RESULTS Inhibition of cGMP accumulation in the cells did not depend on changes in intracellular Ca(2+) concentration. Degradation of cGMP and inactivation of NO were both inhibited by the CaM antagonists, ruling out increased loss of cGMP or NO as explanations. Instead, calmidazolium directly inhibited purified sGC (IC(50)= 10 microM). The inhibition was not in competition with NO, nor did it arise from displacement of the haem moiety from sGC. Calmidazolium decreased enzyme V(max) and K(m), indicating that it acts in an uncompetitive manner. CONCLUSIONS AND IMPLICATIONS The disruption of every stage of NO signal transduction by common CaM antagonists, unrelated to CaM antagonism, cautions against their utility as pharmacological tools. More positively, the compounds exemplify a novel class of sGC inhibitors that, with improved selectivity, may be therapeutically valuable.
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14
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Singaravelu K, Lohr C, Deitmer JW. Calcium-independent phospholipase A2 mediates store-operated calcium entry in rat cerebellar granule cells. THE CEREBELLUM 2009; 7:467-81. [PMID: 18784973 DOI: 10.1007/s12311-008-0050-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Store-operated Ca(2+) entry (SOCE) has been extensively studied in non-neuronal cells, such as glial cells and smooth muscle cells, in which Ca(2+)-independent phospholipase A(2) (iPLA(2)) has been shown to play a key role in the regulation of SOCE channels. In the present study, we have investigated the role of iPLA(2) for store-operated Ca(2+) entry in rat cerebellar granule neurons in acute brain slices using confocal Ca(2+) imaging. Depletion of Ca(2+) stores by cyclopiazonic acid (CPA) induced a Ca(2+) influx, which could be inhibited by SOCE channel blockers 2-aminoethoxy-diphenylborate (2-APB) and 3,5-bistrifluoromethyl pyrazole derivative (BTP2), but not by the voltage-operated Ca(2+) channel blocker diltiazem and by the Na+ channel blocker tetrodotoxin. The inhibitors of iPLA(2), bromoenol lactone (BEL) and 1,1,1-trifluoro-2-heptadecanone, and the selective suppression of iPLA(2) expression by antisense oligodeoxynucleotides, inhibited CPA-induced Ca(2+) influx. Calmidazolium, which relieves the block of inhibitory calmodulin from iPLA(2), elicited a Ca(2+) influx similar to CPA-induced Ca(2+) entry. The product of iPLA(2), lysophosphatidylinositol, elicited a 2-APB- and BTP2-sensitive, but BEL-insensitive, Ca(2+) influx. Spontaneous Ca(2+) oscillations in granule cells in acute brain slices were reduced after inhibiting iPLA(2) activity or by blocking SOCE channels. The results suggest that depletion of Ca(2+) stores activates iPLA(2) to trigger Ca(2+) influx by the formation of lysophospholipids in these neurons.
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Pierre S, Eschenhagen T, Geisslinger G, Scholich K. Capturing adenylyl cyclases as potential drug targets. Nat Rev Drug Discov 2009; 8:321-35. [PMID: 19337273 DOI: 10.1038/nrd2827] [Citation(s) in RCA: 169] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cyclic AMP (cAMP) is an important intracellular signalling mediator. It is generated in mammals by nine membrane-bound and one soluble adenylyl cyclases (ACs), each with distinct regulation and expression patterns. Although many drugs inhibit or stimulate AC activity through the respective upstream G-protein coupled receptors (for example, opioid or beta-adrenergic receptors), ACs themselves have not been major drug targets. Over the past decade studies on the physiological functions of the different mammalian AC isoforms as well as advances in the development of isoform-selective AC inhibitors and activators suggest that ACs could be useful drug targets. Here we discuss the therapeutic potential of isoform-selective compounds in various clinical settings, including neuropathic pain, neurodegenerative disorders, congestive heart failure, asthma and male contraception.
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Affiliation(s)
- Sandra Pierre
- Pharmazentrum Frankfurt, ZAFES, Institut für Klinische Pharmakologie, Klinikum der Goethe-Universität Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany
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16
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Sadana R, Dessauer CW. Physiological roles for G protein-regulated adenylyl cyclase isoforms: insights from knockout and overexpression studies. Neurosignals 2008; 17:5-22. [PMID: 18948702 DOI: 10.1159/000166277] [Citation(s) in RCA: 257] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2008] [Accepted: 04/22/2008] [Indexed: 01/08/2023] Open
Abstract
Cyclic AMP is a universal second messenger, produced by a family of adenylyl cyclase (AC) enzymes. The last three decades have brought a wealth of new information about the regulation of cyclic AMP production by ACs. Nine hormone-sensitive, membrane-bound AC isoforms have been identified in addition to a tenth isoform that lacks membrane spans and more closely resembles the cyanobacterial AC enzymes. New model systems for purifying and characterizing the catalytic domains of AC have led to the crystal structure of these domains and the mapping of numerous interaction sites. However, big hurdles remain in unraveling the roles of individual AC isoforms and their regulation in physiological systems. In this review we explore the latest on AC knockout and overexpression studies to better understand the roles of G protein regulation of ACs in the brain, olfactory bulb, and heart.
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Affiliation(s)
- Rachna Sadana
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
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Singaravelu K, Lohr C, Deitmer JW. Regulation of store-operated calcium entry by calcium-independent phospholipase A2 in rat cerebellar astrocytes. J Neurosci 2006; 26:9579-92. [PMID: 16971542 PMCID: PMC6674595 DOI: 10.1523/jneurosci.2604-06.2006] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We have studied store-operated Ca2+ entry (SOCE) in Bergmann glia and granule cell layer astrocytes in acute brain slices of the rat cerebellum, using the Ca2+-sensitive fluorescent dye Fluo-4 and confocal laser scanning microscopy. Astrocytes were identified by their morphology, location, and their Ca2+ response in K+-free solution. Depletion of Ca2+ stores by cyclopiazonic acid (CPA) (20 microM) induced SOCE in both types of astrocyte. A similar Ca2+ influx was elicited by the calmodulin antagonist calmidazolium (CMZ) (1 microM). The SOCE channel blocker 2-aminoethoxy-diphenylborate (2-APB) (100 microM) and the Ca2+ release-activated channel blocker 3,5-bistrifluoromethyl pyrazole derivative (BTP2) (20 microM) suppressed the CPA- and the CMZ-induced Ca2+ influx. Pretreatment of acute slices with the specific Ca2+-independent phospholipase A2 (iPLA2) inhibitor bromoenol lactone (BEL) (25 microM) blocked the CPA- and the CMZ-induced Ca2+ influx. The lysophospholipid products of iPLA2, lysophosphatidylcholine (250 nM) and lysophosphatidylinositol (250 nM), but not lysophosphatidic acid (250 nM), induced a BTP2- and 2-APB-sensitive, but BEL-insensitive, Ca2+ influx. CPA or CMZ enhanced the BEL-sensitive enzymatic activity of iPLA2 in cerebellar astrocyte culture. Inhibition of iPLA2 expression by specific antisense oligodeoxynucleotide of iPLA2 reduced the SOCE and the Ca2+ store refilling in cultured astrocytes. Spontaneous Ca2+ oscillations in astrocytes in situ were reduced after inhibiting SOCE channels or iPLA2 activity. The results suggest that the depletion of Ca2+ stores activates iPLA2 to open Ca2+ channels in the plasma membrane by the formation of lysophospholipids in astrocytes, presumably to refill the stores and allow normal Ca2+ signaling.
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Affiliation(s)
- Karthika Singaravelu
- Abteilung für Allgemeine Zoologie, Fachbereich Biologie, Technische Universität Kaiserslautern, D-67653 Kaiserslautern, Germany
| | - Christian Lohr
- Abteilung für Allgemeine Zoologie, Fachbereich Biologie, Technische Universität Kaiserslautern, D-67653 Kaiserslautern, Germany
| | - Joachim W. Deitmer
- Abteilung für Allgemeine Zoologie, Fachbereich Biologie, Technische Universität Kaiserslautern, D-67653 Kaiserslautern, Germany
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18
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Kamenetsky M, Middelhaufe S, Bank EM, Levin LR, Buck J, Steegborn C. Molecular details of cAMP generation in mammalian cells: a tale of two systems. J Mol Biol 2006; 362:623-39. [PMID: 16934836 PMCID: PMC3662476 DOI: 10.1016/j.jmb.2006.07.045] [Citation(s) in RCA: 241] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2006] [Revised: 07/15/2006] [Accepted: 07/20/2006] [Indexed: 01/05/2023]
Abstract
The second messenger cAMP has been extensively studied for half a century, but the plethora of regulatory mechanisms controlling cAMP synthesis in mammalian cells is just beginning to be revealed. In mammalian cells, cAMP is produced by two evolutionary related families of adenylyl cyclases, soluble adenylyl cyclases (sAC) and transmembrane adenylyl cyclases (tmAC). These two enzyme families serve distinct physiological functions. They share a conserved overall architecture in their catalytic domains and a common catalytic mechanism, but they differ in their sub-cellular localizations and responses to various regulators. The major regulators of tmACs are heterotrimeric G proteins, which transduce extracellular signals via G protein-coupled receptors. sAC enzymes, in contrast, are regulated by the intracellular signaling molecules bicarbonate and calcium. Here, we discuss and compare the biochemical, structural and regulatory characteristics of the two mammalian AC families. This comparison reveals the mechanisms underlying their different properties but also illustrates many unifying themes for these evolutionary related signaling enzymes.
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Affiliation(s)
- Margarita Kamenetsky
- Department of Pharmacology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10021, USA
| | - Sabine Middelhaufe
- Department of Physiological Chemistry, Ruhr-University, Bochum, Universitätsstraße
| | - Erin M. Bank
- Department of Pharmacology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10021, USA
| | - Lonny R. Levin
- Department of Pharmacology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10021, USA
- Corresponding authors: ;
| | - Jochen Buck
- Department of Pharmacology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10021, USA
| | - Clemens Steegborn
- Department of Physiological Chemistry, Ruhr-University, Bochum, Universitätsstraße
- Corresponding authors: ;
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Wachten S, Schlenstedt J, Gauss R, Baumann A. Molecular identification and functional characterization of an adenylyl cyclase from the honeybee. J Neurochem 2006; 96:1580-90. [PMID: 16464235 DOI: 10.1111/j.1471-4159.2006.03666.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cyclic AMP (cAMP) serves as an important messenger in virtually all organisms. In the honeybee (Apis mellifera), cAMP-dependent signal transduction has been implicated in behavioural processes as well as in learning and memory. Key components of cAMP-signalling cascades are adenylyl cyclases. However, the molecular identities and biochemical properties of adenylyl cyclases are completely unknown in the honeybee. We have cloned a cDNA (Amac3) from honeybee brain that encodes a membrane-bound adenylyl cyclase. The Amac3 gene is an orthologue of the Drosophila ac39E gene. The corresponding proteins share an overall amino acid similarity of approximately 62%. Phylogenetically, AmAC3 belongs to group 1 adenylyl cyclases. Heterologously expressed AmAC3 displays basal enzymatic activity and efficient coupling to endogenous G protein signalling pathways. Stimulation of beta-adrenergic receptors induces AmAC3 activity with an EC(50) of about 3.1 microm. Enzymatic activity is also increased by forskolin (EC(50) approximately 15 microm), a specific agonist of membrane-bound adenylyl cyclases. Similar to certain biogenic amine receptor genes of the honeybee, Amac3 transcripts are expressed in many somata of the brain, especially in mushroom body neurones. These results suggest that the enzyme serves in biogenic amine signal transduction cascades and in higher brain functions that contribute to learning and memory of the bee.
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Affiliation(s)
- Sebastian Wachten
- Institut für Biologische Informationsverarbeitung 1, Forschungszentrum Jülich, Jülich, Germany
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Steegborn C, Litvin TN, Hess KC, CapperM AB, Taussig R, Buck J, Levin LR, Wu H. A novel mechanism for adenylyl cyclase inhibition from the crystal structure of its complex with catechol estrogen. J Biol Chem 2005; 280:31754-9. [PMID: 16002394 PMCID: PMC3650720 DOI: 10.1074/jbc.m507144200] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Catechol estrogens are steroid metabolites that elicit physiological responses through binding to a variety of cellular targets. We show here that catechol estrogens directly inhibit soluble adenylyl cyclases and the abundant trans-membrane adenylyl cyclases. Catechol estrogen inhibition is non-competitive with respect to the substrate ATP, and we solved the crystal structure of a catechol estrogen bound to a soluble adenylyl cyclase from Spirulina platensis in complex with a substrate analog. The catechol estrogen is bound to a newly identified, conserved hydrophobic patch near the active center but distinct from the ATP-binding cleft. Inhibitor binding leads to a chelating interaction between the catechol estrogen hydroxyl groups and the catalytic magnesium ion, distorting the active site and trapping the enzyme substrate complex in a non-productive conformation. This novel inhibition mechanism likely applies to other adenylyl cyclase inhibitors, and the identified ligand-binding site has important implications for the development of specific adenylyl cyclase inhibitors.
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Affiliation(s)
- Clemens Steegborn
- ‡Department of Biochemistry, Weill Medical College of Cornell University, New York, New York 10021
| | - Tatiana N. Litvin
- Department of Pharmacology, Weill Medical College of Cornell University, New York, New York 10021
| | - Kenneth C. Hess
- Department of Pharmacology, Weill Medical College of Cornell University, New York, New York 10021
| | - Austin B. CapperM
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Ronald Taussig
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Jochen Buck
- Department of Pharmacology, Weill Medical College of Cornell University, New York, New York 10021
| | - Lonny R. Levin
- Department of Pharmacology, Weill Medical College of Cornell University, New York, New York 10021
| | - Hao Wu
- ‡Department of Biochemistry, Weill Medical College of Cornell University, New York, New York 10021
- A Pew Scholar of Biomedical Sciences, a Rita Allen Scholar, and to whom correspondence should be addressed: Dept. of Biochemistry, W206, Weill Medical College of Cornell University, 1300 York Ave., New York, NY 10021. Tel.: 212-746-6451; Fax: 212-746-4843;
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Tseng LL, Huang CJ, Hsu SS, Chen JS, Cheng HH, Chang HT, Jiann BP, Jan CR. Effect of calmidazolium on Ca2+ movement and proliferation in human osteosarcoma cells. Clin Exp Pharmacol Physiol 2004; 31:732-7. [PMID: 15554916 DOI: 10.1111/j.1440-1681.2004.04087.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In human MG63 osteosarcoma cells, the effect of calmidazolium on [Ca(2+)](i) and proliferation was explored using fura-2 and ELISA, respectively. Calmidazolium, at concentrations greater than 0.1 micromol/L, caused a rapid increase in [Ca(2+)](i) in a concentration-dependent manner (EC(50) = 0.5 micromol/L). The calmidazolium-induced [Ca(2+)](i) increase was reduced by 66% by removal of extracellular Ca(2+). In Ca(2+)-free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca(2+)-ATPase, caused a monophasic increase in [Ca(2+)](i), after which the effect of calmidazolium to increase [Ca(2+)](i) was completely inhibited. U73122, an inhibitor of phospholipase C (PLC), abolished histamine (but not calmidazolium)-induced increases in [Ca(2+)](i). Pretreatment with phorbol 12-myristate 13-acetate to activate protein kinase C inhibited the calmidazolium-induced increase in [Ca(2+)](i) in Ca(2+)-containing medium by 47%. Separately, it was found that overnight treatment with 2-10 micromol/L calmidazolium inhibited cell proliferation in a concentration-dependent manner. These results suggest that calmidazolium increases [Ca(2+)](i) by stimulating extracellular Ca(2+) influx and also by causing release of intracellular Ca(2+) from the endoplasmic reticulum in a PLC-independent manner. Calmidazolium may be cytotoxic to osteosarcoma cells.
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Affiliation(s)
- Li-Lin Tseng
- Department of Dentistry, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
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