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Gardner OFW, Bai T, Baillie GS, Ferretti P. Phosphodiesterase 4D activity in acrodysostosis-associated neural pathology: too much or too little? Brain Commun 2024; 6:fcae225. [PMID: 38983619 PMCID: PMC11232698 DOI: 10.1093/braincomms/fcae225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 05/09/2024] [Accepted: 06/27/2024] [Indexed: 07/11/2024] Open
Abstract
Members of the phosphodiesterase 4 (PDE4) enzyme family regulate the availability of the secondary messenger cyclic adenosine monophosphate (cAMP) and, by doing so, control cellular processes in health and disease. In particular, PDE4D has been associated with Alzheimer's disease and the intellectual disability seen in fragile X syndrome. Furthermore, single point mutations in critical PDE4D regions cause acrodysostosis type 2(ACRDYS2, also referred to as inactivating PTH/PTHrP signalling disorder 5 or iPPSD5), where intellectual disability is seen in ∼90% of patients alongside the skeletal dysmorphologies that are characteristic of acrodysostosis type 1 (ACRDYS1/iPPSD4) and ACRDYS2. Two contrasting mechanisms have been proposed to explain how mutations in PDE4D cause iPPSD5. The first mechanism, the 'over-activation hypothesis', suggests that cAMP/PKA (cyclic adenosine monophosphate/protein kinase A) signalling is reduced by the overactivity of mutant PDE4D, whilst the second, the 'over-compensation hypothesis' suggests that mutations reduce PDE4D activity. That reduction in activity is proposed to cause an increase in cellular cAMP, triggering the overexpression of other PDE isoforms. The resulting over-compensation then reduces cellular cAMP and the levels of cAMP/PKA signalling. However, neither of these proposed mechanisms accounts for the fine control of PDE activation and localization, which are likely to play a role in the development of iPPSD5. This review will draw together our understanding of the role of PDE4D in iPPSD5 and present a novel perspective on possible mechanisms of disease.
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Affiliation(s)
- Oliver F W Gardner
- Developmental Biology and Cancer Department, University College London Great Ormond Street Institute of Child Health, London WC1N 1EH, UK
| | - Tianshu Bai
- Developmental Biology and Cancer Department, University College London Great Ormond Street Institute of Child Health, London WC1N 1EH, UK
| | - George S Baillie
- School of Cardiovascular & Metabolic Health, University of Glasgow, Glasgow G12 8QQ, UK
| | - Patrizia Ferretti
- Developmental Biology and Cancer Department, University College London Great Ormond Street Institute of Child Health, London WC1N 1EH, UK
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2
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Fu Q, Wang Y, Yan C, Xiang YK. Phosphodiesterase in heart and vessels: from physiology to diseases. Physiol Rev 2024; 104:765-834. [PMID: 37971403 PMCID: PMC11281825 DOI: 10.1152/physrev.00015.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 10/17/2023] [Accepted: 11/08/2023] [Indexed: 11/19/2023] Open
Abstract
Phosphodiesterases (PDEs) are a superfamily of enzymes that hydrolyze cyclic nucleotides, including cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). Both cyclic nucleotides are critical secondary messengers in the neurohormonal regulation in the cardiovascular system. PDEs precisely control spatiotemporal subcellular distribution of cyclic nucleotides in a cell- and tissue-specific manner, playing critical roles in physiological responses to hormone stimulation in the heart and vessels. Dysregulation of PDEs has been linked to the development of several cardiovascular diseases, such as hypertension, aneurysm, atherosclerosis, arrhythmia, and heart failure. Targeting these enzymes has been proven effective in treating cardiovascular diseases and is an attractive and promising strategy for the development of new drugs. In this review, we discuss the current understanding of the complex regulation of PDE isoforms in cardiovascular function, highlighting the divergent and even opposing roles of PDE isoforms in different pathogenesis.
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Affiliation(s)
- Qin Fu
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- The Key Laboratory for Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan, China
| | - Ying Wang
- Department of Pharmacology, School of Medicine, Southern University of Science and Technology, Shenzhen, China
| | - Chen Yan
- Aab Cardiovascular Research Institute, University of Rochester Medical Center, Rochester, New York, United States
| | - Yang K Xiang
- Department of Pharmacology, University of California at Davis, Davis, California, United States
- Department of Veterans Affairs Northern California Healthcare System, Mather, California, United States
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Wright TA, Gemmell AO, Tejeda GS, Blair CM, Baillie GS. Cancer: Phosphodiesterase type 4C (PDE4C), the forgotten subfamily as a therapeutic target. Int J Biochem Cell Biol 2023; 162:106453. [PMID: 37499270 DOI: 10.1016/j.biocel.2023.106453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 07/13/2023] [Accepted: 07/20/2023] [Indexed: 07/29/2023]
Abstract
Phosphodiesterase type 4 (PDE4) enzymes specifically hydrolyse cAMP in many cell signalling systems that are transduced by hormones and other primary messengers. The physiological function of the four PDE4 subfamilies (A, B, C and D) are numerous and varied due to the differentially localised plethora of isoforms that can be detected in cardiovascular, CNS and immune systems. Of the four subfamilies, least is known about PDE4C probably due to its restricted distribution pattern, scarcity of selective inhibitors and the lack of developed research tools. Here, for the first time, we chart the discovery of PDE4C, describe its regulation and highlight cancers where future development of PDE4C selective small molecules may have potential.
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Affiliation(s)
- Thomas A Wright
- School of Cardiovascular and Metabolic Health, College of Veterinary Medical and Life Science, University of Glasgow, Glasgow, UK
| | - Alistair O Gemmell
- School of Cardiovascular and Metabolic Health, College of Veterinary Medical and Life Science, University of Glasgow, Glasgow, UK
| | - Gonzalo S Tejeda
- School of Cardiovascular and Metabolic Health, College of Veterinary Medical and Life Science, University of Glasgow, Glasgow, UK
| | - Connor M Blair
- School of Cardiovascular and Metabolic Health, College of Veterinary Medical and Life Science, University of Glasgow, Glasgow, UK
| | - George S Baillie
- School of Cardiovascular and Metabolic Health, College of Veterinary Medical and Life Science, University of Glasgow, Glasgow, UK.
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Roy D, Balasubramanian S, Krishnamurthy PT, Sola P, Rymbai E. Phosphodiesterase-4 Inhibition in Parkinson's Disease: Molecular Insights and Therapeutic Potential. Cell Mol Neurobiol 2023:10.1007/s10571-023-01349-1. [PMID: 37074485 DOI: 10.1007/s10571-023-01349-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 04/09/2023] [Indexed: 04/20/2023]
Abstract
Clinicians and researchers are exploring safer and novel treatment strategies for treating the ever-prevalent Parkinson's disease (PD) across the globe. Several therapeutic strategies are used clinically for PD, including dopamine replacement therapy, DA agonists, MAO-B blockers, COMT blockers, and anticholinergics. Surgical interventions such as pallidotomy, particularly deep brain stimulation (DBS), are also employed. However, they only provide temporal and symptomatic relief. Cyclic adenosine monophosphate (cAMP) is one of the secondary messengers involved in dopaminergic neurotransmission. Phosphodiesterase (PDE) regulates cAMP and cGMP intracellular levels. PDE enzymes are subdivided into families and subtypes which are expressed throughout the human body. PDE4 isoenzyme- PDE4B subtype is overexpressed in the substantia nigra of the brain. Various studies have implicated multiple cAMP-mediated signaling cascades in PD, and PDE4 is a common link that can emerge as a neuroprotective and/or disease-modifying target. Furthermore, a mechanistic understanding of the PDE4 subtypes has provided perceptivity into the molecular mechanisms underlying the adverse effects of phosphodiesterase-4 inhibitors (PDE4Is). The repositioning and development of efficacious PDE4Is for PD have gained much attention. This review critically assesses the existing literature on PDE4 and its expression. Specifically, this review provides insights into the interrelated neurological cAMP-mediated signaling cascades involving PDE4s and the potential role of PDE4Is in PD. In addition, we discuss existing challenges and possible strategies for overcoming them.
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Affiliation(s)
- Dhritiman Roy
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, The Nilgiris, Ooty, 643001, Tamil Nadu, India
| | - Shivaramakrishnan Balasubramanian
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, The Nilgiris, Ooty, 643001, Tamil Nadu, India.
| | - Praveen Thaggikuppe Krishnamurthy
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, The Nilgiris, Ooty, 643001, Tamil Nadu, India
| | - Piyong Sola
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, The Nilgiris, Ooty, 643001, Tamil Nadu, India
| | - Emdormi Rymbai
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, The Nilgiris, Ooty, 643001, Tamil Nadu, India
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Cyclic nucleotide phosphodiesterases as therapeutic targets in cardiac hypertrophy and heart failure. Nat Rev Cardiol 2023; 20:90-108. [PMID: 36050457 DOI: 10.1038/s41569-022-00756-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/11/2022] [Indexed: 01/21/2023]
Abstract
Cyclic nucleotide phosphodiesterases (PDEs) modulate the neurohormonal regulation of cardiac function by degrading cAMP and cGMP. In cardiomyocytes, multiple PDE isozymes with different enzymatic properties and subcellular localization regulate local pools of cyclic nucleotides and specific functions. This organization is heavily perturbed during cardiac hypertrophy and heart failure (HF), which can contribute to disease progression. Clinically, PDE inhibition has been considered a promising approach to compensate for the catecholamine desensitization that accompanies HF. Although PDE3 inhibitors, such as milrinone or enoximone, have been used clinically to improve systolic function and alleviate the symptoms of acute HF, their chronic use has proved to be detrimental. Other PDEs, such as PDE1, PDE2, PDE4, PDE5, PDE9 and PDE10, have emerged as new potential targets to treat HF, each having a unique role in local cyclic nucleotide signalling pathways. In this Review, we describe cAMP and cGMP signalling in cardiomyocytes and present the various PDE families expressed in the heart as well as their modifications in pathological cardiac hypertrophy and HF. We also appraise the evidence from preclinical models as well as clinical data pointing to the use of inhibitors or activators of specific PDEs that could have therapeutic potential in HF.
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Paes D, Schepers M, Rombaut B, van den Hove D, Vanmierlo T, Prickaerts J. The Molecular Biology of Phosphodiesterase 4 Enzymes as Pharmacological Targets: An Interplay of Isoforms, Conformational States, and Inhibitors. Pharmacol Rev 2021; 73:1016-1049. [PMID: 34233947 DOI: 10.1124/pharmrev.120.000273] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The phosphodiesterase 4 (PDE4) enzyme family plays a pivotal role in regulating levels of the second messenger cAMP. Consequently, PDE4 inhibitors have been investigated as a therapeutic strategy to enhance cAMP signaling in a broad range of diseases, including several types of cancers, as well as in various neurologic, dermatological, and inflammatory diseases. Despite their widespread therapeutic potential, the progression of PDE4 inhibitors into the clinic has been hampered because of their related relatively small therapeutic window, which increases the chance of producing adverse side effects. Interestingly, the PDE4 enzyme family consists of several subtypes and isoforms that can be modified post-translationally or can engage in specific protein-protein interactions to yield a variety of conformational states. Inhibition of specific PDE4 subtypes, isoforms, or conformational states may lead to more precise effects and hence improve the safety profile of PDE4 inhibition. In this review, we provide an overview of the variety of PDE4 isoforms and how their activity and inhibition is influenced by post-translational modifications and interactions with partner proteins. Furthermore, we describe the importance of screening potential PDE4 inhibitors in view of different PDE4 subtypes, isoforms, and conformational states rather than testing compounds directed toward a specific PDE4 catalytic domain. Lastly, potential mechanisms underlying PDE4-mediated adverse effects are outlined. In this review, we illustrate that PDE4 inhibitors retain their therapeutic potential in myriad diseases, but target identification should be more precise to establish selective inhibition of disease-affected PDE4 isoforms while avoiding isoforms involved in adverse effects. SIGNIFICANCE STATEMENT: Although the PDE4 enzyme family is a therapeutic target in an extensive range of disorders, clinical use of PDE4 inhibitors has been hindered because of the adverse side effects. This review elaborately shows that safer and more effective PDE4 targeting is possible by characterizing 1) which PDE4 subtypes and isoforms exist, 2) how PDE4 isoforms can adopt specific conformations upon post-translational modifications and protein-protein interactions, and 3) which PDE4 inhibitors can selectively bind specific PDE4 subtypes, isoforms, and/or conformations.
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Affiliation(s)
- Dean Paes
- Department of Psychiatry & Neuropsychology, School for Mental Health and Neuroscience, EURON, Maastricht University, Maastricht, The Netherlands (D.P, M.S., B.R., D.v.d.H., T.V., J.P.); Department of Neuroscience, Neuro-Immune Connect and Repair laboratory, Biomedical Research Institute, Hasselt University, Hasselt, Belgium (D.P., M.S., B.R., T.V.); and Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, Würzburg, Germany (D.v.d.H.)
| | - Melissa Schepers
- Department of Psychiatry & Neuropsychology, School for Mental Health and Neuroscience, EURON, Maastricht University, Maastricht, The Netherlands (D.P, M.S., B.R., D.v.d.H., T.V., J.P.); Department of Neuroscience, Neuro-Immune Connect and Repair laboratory, Biomedical Research Institute, Hasselt University, Hasselt, Belgium (D.P., M.S., B.R., T.V.); and Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, Würzburg, Germany (D.v.d.H.)
| | - Ben Rombaut
- Department of Psychiatry & Neuropsychology, School for Mental Health and Neuroscience, EURON, Maastricht University, Maastricht, The Netherlands (D.P, M.S., B.R., D.v.d.H., T.V., J.P.); Department of Neuroscience, Neuro-Immune Connect and Repair laboratory, Biomedical Research Institute, Hasselt University, Hasselt, Belgium (D.P., M.S., B.R., T.V.); and Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, Würzburg, Germany (D.v.d.H.)
| | - Daniel van den Hove
- Department of Psychiatry & Neuropsychology, School for Mental Health and Neuroscience, EURON, Maastricht University, Maastricht, The Netherlands (D.P, M.S., B.R., D.v.d.H., T.V., J.P.); Department of Neuroscience, Neuro-Immune Connect and Repair laboratory, Biomedical Research Institute, Hasselt University, Hasselt, Belgium (D.P., M.S., B.R., T.V.); and Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, Würzburg, Germany (D.v.d.H.)
| | - Tim Vanmierlo
- Department of Psychiatry & Neuropsychology, School for Mental Health and Neuroscience, EURON, Maastricht University, Maastricht, The Netherlands (D.P, M.S., B.R., D.v.d.H., T.V., J.P.); Department of Neuroscience, Neuro-Immune Connect and Repair laboratory, Biomedical Research Institute, Hasselt University, Hasselt, Belgium (D.P., M.S., B.R., T.V.); and Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, Würzburg, Germany (D.v.d.H.)
| | - Jos Prickaerts
- Department of Psychiatry & Neuropsychology, School for Mental Health and Neuroscience, EURON, Maastricht University, Maastricht, The Netherlands (D.P, M.S., B.R., D.v.d.H., T.V., J.P.); Department of Neuroscience, Neuro-Immune Connect and Repair laboratory, Biomedical Research Institute, Hasselt University, Hasselt, Belgium (D.P., M.S., B.R., T.V.); and Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, Würzburg, Germany (D.v.d.H.)
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7
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Furlan V, Bren U. Insight into Inhibitory Mechanism of PDE4D by Dietary Polyphenols Using Molecular Dynamics Simulations and Free Energy Calculations. Biomolecules 2021; 11:479. [PMID: 33806914 PMCID: PMC8004924 DOI: 10.3390/biom11030479] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 03/19/2021] [Accepted: 03/21/2021] [Indexed: 12/11/2022] Open
Abstract
Phosphodiesterase 4 (PDE4), mainly present in immune, epithelial, and brain cells, represents a family of key enzymes for the degradation of cyclic adenosine monophosphate (cAMP), which modulates inflammatory response. In recent years, the inhibition of PDE4 has been proven to be an effective therapeutic strategy for the treatment of neurological disorders. PDE4D constitutes a high-interest therapeutic target primarily for the treatment of Alzheimer's disease, as it is highly involved in neuroinflammation, learning ability, and memory dysfunctions. In the present study, a thorough computational investigation consisting of molecular docking, molecular dynamics (MD) simulations, and binding free energy calculations based on the linear response approximation (LRA) method was performed to study dietary polyphenols as potential PDE4D inhibitors. The obtained results revealed that curcumin, 6-gingerol, capsaicin, and resveratrol represent potential PDE4D inhibitors; however, the predicted binding free energies of 6-gingerol, capsaicin, and resveratrol were less negative than in the case of curcumin, which exhibited the highest inhibitory potency in comparison with a positive control rolipram. Our results also revealed that the electrostatic component through hydrogen bonding represents the main driving force for the binding and inhibitory activity of curcumin, 6-gingerol, and resveratrol, while the van der Waals component through shape complementarity plays the most important role in capsaicin's inhibitory activity. All investigated compounds form hydrophobic interactions with residues Gln376 and Asn602 as well as hydrogen bonds with nearby residues Asp438, Met439, and Ser440. The binding mode of the studied natural compounds is consequently very similar; however, it significantly differs from the binding of known PDE4 inhibitors. The uncovered molecular inhibitory mechanisms of four investigated natural polyphenols, curcumin, 6-gingerol, capsaicin, and resveratrol, form the basis for the design of novel PDE4D inhibitors for the treatment of Alzheimer's disease with a potentially wider therapeutic window and fewer adverse side effects.
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Affiliation(s)
- Veronika Furlan
- Faculty of Chemistry and Chemical Engineering, University of Maribor, Smetanova 17, SI-2000 Maribor, Slovenia;
| | - Urban Bren
- Faculty of Chemistry and Chemical Engineering, University of Maribor, Smetanova 17, SI-2000 Maribor, Slovenia;
- Faculty of Mathematics, Natural Sciences and Information Technologies, University of Primorska, Glagoljaška 8, SI-6000 Koper, Slovenia
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Dominant-Negative Attenuation of cAMP-Selective Phosphodiesterase PDE4D Action Affects Learning and Behavior. Int J Mol Sci 2020; 21:ijms21165704. [PMID: 32784895 PMCID: PMC7460819 DOI: 10.3390/ijms21165704] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Revised: 07/26/2020] [Accepted: 08/06/2020] [Indexed: 12/22/2022] Open
Abstract
PDE4 cyclic nucleotide phosphodiesterases reduce 3′, 5′ cAMP levels in the CNS and thereby regulate PKA activity and the phosphorylation of CREB, fundamental to depression, cognition, and learning and memory. The PDE4 isoform PDE4D5 interacts with the signaling proteins β-arrestin2 and RACK1, regulators of β2-adrenergic and other signal transduction pathways. Mutations in PDE4D in humans predispose to acrodysostosis, associated with cognitive and behavioral deficits. To target PDE4D5, we developed mice that express a PDE4D5-D556A dominant-negative transgene in the brain. Male transgenic mice demonstrated significant deficits in hippocampus-dependent spatial learning, as assayed in the Morris water maze. In contrast, associative learning, as assayed in a fear conditioning assay, appeared to be unaffected. Male transgenic mice showed augmented activity in prolonged (2 h) open field testing, while female transgenic mice showed reduced activity in the same assay. Transgenic mice showed no demonstrable abnormalities in prepulse inhibition. There was also no detectable difference in anxiety-like behavior, as measured in the elevated plus-maze. These data support the use of a dominant-negative approach to the study of PDE4D5 function in the CNS and specifically in learning and memory.
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Tibbo AJ, Baillie GS. Phosphodiesterase 4B: Master Regulator of Brain Signaling. Cells 2020; 9:cells9051254. [PMID: 32438615 PMCID: PMC7291338 DOI: 10.3390/cells9051254] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 05/13/2020] [Accepted: 05/14/2020] [Indexed: 12/25/2022] Open
Abstract
Phosphodiesterases (PDEs) are the only superfamily of enzymes that have the ability to break down cyclic nucleotides and, as such, they have a pivotal role in neurological disease and brain development. PDEs have a modular structure that allows targeting of individual isoforms to discrete brain locations and it is often the location of a PDE that shapes its cellular function. Many of the eleven different families of PDEs have been associated with specific diseases. However, we evaluate the evidence, which suggests the activity from a sub-family of the PDE4 family, namely PDE4B, underpins a range of important functions in the brain that positions the PDE4B enzymes as a therapeutic target for a diverse collection of indications, such as, schizophrenia, neuroinflammation, and cognitive function.
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Blokland A, Heckman P, Vanmierlo T, Schreiber R, Paes D, Prickaerts J. Phosphodiesterase Type 4 Inhibition in CNS Diseases. Trends Pharmacol Sci 2019; 40:971-985. [DOI: 10.1016/j.tips.2019.10.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 10/15/2019] [Accepted: 10/17/2019] [Indexed: 12/17/2022]
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Stathopoulou K, Schobesberger S, Bork NI, Sprenger JU, Perera RK, Sotoud H, Geertz B, David JP, Christ T, Nikolaev VO, Cuello F. Divergent off-target effects of RSK N-terminal and C-terminal kinase inhibitors in cardiac myocytes. Cell Signal 2019; 63:109362. [PMID: 31344438 DOI: 10.1016/j.cellsig.2019.109362] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 07/18/2019] [Accepted: 07/18/2019] [Indexed: 12/15/2022]
Abstract
P90 ribosomal S6 kinases (RSK) are ubiquitously expressed and regulate responses to neurohumoral stimulation. To study the role of RSK signalling on cardiac myocyte function and protein phosphorylation, pharmacological RSK inhibitors were tested. Here, the ATP competitive N-terminal kinase domain-targeting compounds D1870 and SL0101 and the allosteric C-terminal kinase domain-targeting FMK were evaluated regarding their ability to modulate cardiac myocyte protein phosphorylation. Exposure to D1870 and SL0101 significantly enhanced phospholamban (PLN) Ser16 and cardiac troponin I (cTnI) Ser22/23 phosphorylation in response to D1870 and SL0101 upon exposure to phenylephrine (PE) that activates RSK. In contrast, FMK pretreatment significantly reduced phosphorylation of both proteins in response to PE. D1870-mediated enhancement of PLN Ser16 phosphorylation was also observed after exposure to isoprenaline or noradrenaline (NA) stimuli that do not activate RSK. Inhibition of β-adrenoceptors by atenolol or cAMP-dependent protein kinase (PKA) by H89 prevented the D1870-mediated increase in PLN phosphorylation, suggesting that PKA is the kinase responsible for the observed phosphorylation. Assessment of changes in cAMP formation by FRET measurements revealed increased cAMP formation in vicinity to PLN after exposure to D1870 and SL0101. D1870 inhibited phosphodiesterase activity similarly as established PDE inhibitors rolipram or 3-isobutyl-1-methylxanthine. Assessment of catecholamine-mediated force development in rat ventricular muscle strips revealed significantly reduced EC50 for NA after D1870 pretreatment (DMSO/NA: 2.33 μmol/L vs. D1870/NA: 1.30 μmol/L). The data reveal enhanced cardiac protein phosphorylation by D1870 and SL0101 that was not detectable in response to FMK. This disparate effect might be attributed to off-target inhibition of PDEs with impact on muscle function as demonstrated for D1870.
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Affiliation(s)
- Konstantina Stathopoulou
- Institute of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany; DZHK (German Center for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Sophie Schobesberger
- Institute of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany; DZHK (German Center for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Nadja I Bork
- DZHK (German Center for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany; Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Julia U Sprenger
- DZHK (German Center for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany; Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Ruwan K Perera
- DZHK (German Center for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany; Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Hannieh Sotoud
- Institute of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany; DZHK (German Center for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Birgit Geertz
- Institute of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany; DZHK (German Center for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Jean-Pierre David
- Institute of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Torsten Christ
- Institute of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany; DZHK (German Center for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Viacheslav O Nikolaev
- DZHK (German Center for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany; Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Friederike Cuello
- Institute of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany; DZHK (German Center for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
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12
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Small-molecule allosteric activators of PDE4 long form cyclic AMP phosphodiesterases. Proc Natl Acad Sci U S A 2019; 116:13320-13329. [PMID: 31209056 PMCID: PMC6613170 DOI: 10.1073/pnas.1822113116] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Cyclic AMP (cAMP) phosphodiesterase-4 (PDE4) enzymes degrade cAMP and underpin the compartmentalization of cAMP signaling through their targeting to particular protein complexes and intracellular locales. We describe the discovery and characterization of a small-molecule compound that allosterically activates PDE4 long isoforms. This PDE4-specific activator displays reversible, noncompetitive kinetics of activation (increased V max with unchanged K m), phenocopies the ability of protein kinase A (PKA) to activate PDE4 long isoforms endogenously, and requires a dimeric enzyme assembly, as adopted by long, but not by short (monomeric), PDE4 isoforms. Abnormally elevated levels of cAMP provide a critical driver of the underpinning molecular pathology of autosomal dominant polycystic kidney disease (ADPKD) by promoting cyst formation that, ultimately, culminates in renal failure. Using both animal and human cell models of ADPKD, including ADPKD patient-derived primary cell cultures, we demonstrate that treatment with the prototypical PDE4 activator compound lowers intracellular cAMP levels, restrains cAMP-mediated signaling events, and profoundly inhibits cyst formation. PDE4 activator compounds thus have potential as therapeutics for treating disease driven by elevated cAMP signaling as well as providing a tool for evaluating the action of long PDE4 isoforms in regulating cAMP-mediated cellular processes.
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13
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Gurney ME, Nugent RA, Mo X, Sindac JA, Hagen TJ, Fox D, O'Donnell JM, Zhang C, Xu Y, Zhang HT, Groppi VE, Bailie M, White RE, Romero DL, Vellekoop AS, Walker JR, Surman MD, Zhu L, Campbell RF. Design and Synthesis of Selective Phosphodiesterase 4D (PDE4D) Allosteric Inhibitors for the Treatment of Fragile X Syndrome and Other Brain Disorders. J Med Chem 2019; 62:4884-4901. [PMID: 31013090 DOI: 10.1021/acs.jmedchem.9b00193] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Novel pyridine- and pyrimidine-based allosteric inhibitors are reported that achieve PDE4D subtype selectivity through recognition of a single amino acid difference on a key regulatory domain, known as UCR2, that opens and closes over the catalytic site for cAMP hydrolysis. The design and optimization of lead compounds was based on iterative analysis of X-ray crystal structures combined with metabolite identification. Selectivity for the activated, dimeric form of PDE4D provided potent memory enhancing effects in a mouse model of novel object recognition with improved tolerability and reduced vascular toxicity over earlier PDE4 inhibitors that lack subtype selectivity. The lead compound, 28 (BPN14770), has entered midstage, human phase 2 clinical trials for the treatment of Fragile X Syndrome.
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Affiliation(s)
- Mark E Gurney
- Tetra Discovery Partners, Inc. , 38 Fulton Street West , Grand Rapids , Michigan 49503 , United States
| | - Richard A Nugent
- Tetra Discovery Partners, Inc. , 38 Fulton Street West , Grand Rapids , Michigan 49503 , United States
| | - Xuesheng Mo
- Tetra Discovery Partners, Inc. , 38 Fulton Street West , Grand Rapids , Michigan 49503 , United States
| | - Janice A Sindac
- Tetra Discovery Partners, Inc. , 38 Fulton Street West , Grand Rapids , Michigan 49503 , United States
| | - Timothy J Hagen
- Department of Chemistry and Biochemistry , Northern Illinois University , 1425 West Lincoln Highway , DeKalb , Illinois 60115 , United States
| | - David Fox
- Beryllium Discovery Corp. , 7869 NE Day Road West , Bainbridge Island , Washington 98110 , United States
| | - James M O'Donnell
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences , University at Buffalo, The State University of New York , Buffalo , New York 14214-8033 , United States
| | - Chong Zhang
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences , University at Buffalo, The State University of New York , Buffalo , New York 14214-8033 , United States
| | - Ying Xu
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences , University at Buffalo, The State University of New York , Buffalo , New York 14214-8033 , United States
| | - Han-Ting Zhang
- Departments of Behavioral Medicine & Psychiatry and Physiology, Pharmacology & Neuroscience, Rockefeller Neurosciences Institute , West Virginia University Health Sciences Center , 1 Medical Center Drive , Morgantown , West Virginia 26506 , United States
| | - Vincent E Groppi
- Michigan Drug Discovery, Life Sciences Institute , University of Michigan , 210 Washtenaw Avenue , Ann Arbor , Michigan 48103 , United States
| | - Marc Bailie
- INDS Inc. , 6111 Jackson Road, Suite 100 , Ann Arbor , Michigan 48103 , United States
| | - Ronald E White
- White Global Pharma Consultants , 31 Kinglet Drive , South Cranbury , New Jersey 08512 , United States
| | - Donna L Romero
- Pharma-Vation Consulting, LLC , 1201 Turnberry Ridge Court , Chesterfield , Missouri 63005 , United States
| | - A Samuel Vellekoop
- Albany Molecular Research, Inc. , 21 Corporate Circle , Albany , New York 12203 , United States
| | - Joel R Walker
- Albany Molecular Research, Inc. , 21 Corporate Circle , Albany , New York 12203 , United States
| | - Matthew D Surman
- Albany Molecular Research, Inc. , 21 Corporate Circle , Albany , New York 12203 , United States
| | - Lei Zhu
- Albany Molecular Research, Inc. , 21 Corporate Circle , Albany , New York 12203 , United States
| | - Robert F Campbell
- Albany Molecular Research, Inc. , 21 Corporate Circle , Albany , New York 12203 , United States
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14
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Zuo H, Cattani-Cavalieri I, Musheshe N, Nikolaev VO, Schmidt M. Phosphodiesterases as therapeutic targets for respiratory diseases. Pharmacol Ther 2019; 197:225-242. [PMID: 30759374 DOI: 10.1016/j.pharmthera.2019.02.002] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Chronic respiratory diseases, such as chronic obstructive pulmonary disease (COPD) and asthma, affect millions of people all over the world. Cyclic adenosine monophosphate (cAMP) which is one of the most important second messengers, plays a vital role in relaxing airway smooth muscles and suppressing inflammation. Given its vast role in regulating intracellular responses, cAMP provides an attractive pharmaceutical target in the treatment of chronic respiratory diseases. Phosphodiesterases (PDEs) are enzymes that hydrolyze cyclic nucleotides and help control cyclic nucleotide signals in a compartmentalized manner. Currently, the selective PDE4 inhibitor, roflumilast, is used as an add-on treatment for patients with severe COPD associated with bronchitis and a history of frequent exacerbations. In addition, other novel PDE inhibitors are in different phases of clinical trials. The current review provides an overview of the regulation of various PDEs and the potential application of selective PDE inhibitors in the treatment of COPD and asthma. The possibility to combine various PDE inhibitors as a way to increase their therapeutic effectiveness is also emphasized.
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Affiliation(s)
- Haoxiao Zuo
- Department of Molecular Pharmacology, University of Groningen, the Netherlands; Institute of Experimental Cardiovascular Research, University Medical Centre Hamburg-Eppendorf, 20246 Hamburg, Germany.
| | - Isabella Cattani-Cavalieri
- Department of Molecular Pharmacology, University of Groningen, the Netherlands; Groningen Research Institute for Asthma and COPD, GRIAC, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands; Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Nshunge Musheshe
- Department of Molecular Pharmacology, University of Groningen, the Netherlands
| | - Viacheslav O Nikolaev
- Institute of Experimental Cardiovascular Research, University Medical Centre Hamburg-Eppendorf, 20246 Hamburg, Germany; German Center for Cardiovascular Research (DZHK), 20246 Hamburg, Germany
| | - Martina Schmidt
- Department of Molecular Pharmacology, University of Groningen, the Netherlands; Groningen Research Institute for Asthma and COPD, GRIAC, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
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15
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Gurney ME. Genetic Association of Phosphodiesterases With Human Cognitive Performance. Front Mol Neurosci 2019; 12:22. [PMID: 30800055 PMCID: PMC6376954 DOI: 10.3389/fnmol.2019.00022] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 01/21/2019] [Indexed: 01/03/2023] Open
Abstract
Recent, large-scale, genome-wide association studies (GWAS) provide a first view of the genetic fine structure of cognitive performance in healthy individuals. These studies have pooled data from up to 1.1 million subjects based on simple measures of cognitive performance including educational attainment, self-reported math ability, highest math class taken, and pooled, normalized scores from cognitive tests. These studies now allow the genome-wide interrogation of genes and pathways for their potential impact on human cognitive performance. The phosphodiesterase (PDE) enzymes regulate key cyclic nucleotide signaling pathways. Many are expressed in the brain and have been the targets of CNS drug discovery. Genetic variation in PDE1C, PDE4B and PDE4D associates with multiple measures of human cognitive function. The large size of the human PDE4B and PDE4D genes allows genetic fine structure mapping to transcripts encoding dimeric (long) forms of the enzymes. Upstream and downstream effectors of the cAMP pathway modulated by PDE4D [adenylate cyclase 1 (ADCY1), ADCY8, PRKAR1A, CREB1, or CREBBP] did not show genetic association with cognitive performance, however, genetic association was seen with brain derived neurotrophic factor (BDNF), a gene whose expression is modulated by cAMP. Notably absent was genetic association in healthy subjects to targets of CNS drug discovery designed to improve cognition in disease states by the modulation of cholinergic [acetylcholinesterase (ACHE), choline acetyltransferase (CHAT), nicotinic alpha 7 acetylcholine receptor (CHRNA7)], serotonergic (HTR6), histaminergic (HRH3), or glutamatergic (GRM5) pathways. These new data provide a rationale for exploring the therapeutic benefit of selective inhibitors of PDE1C, PDE4B and PDE4D in CNS disorders affecting cognition.
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Affiliation(s)
- Mark E Gurney
- Tetra Discovery Partners, Grand Rapids, MI, United States
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16
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Memory enhancing effects of BPN14770, an allosteric inhibitor of phosphodiesterase-4D, in wild-type and humanized mice. Neuropsychopharmacology 2018; 43:2299-2309. [PMID: 30131563 PMCID: PMC6135860 DOI: 10.1038/s41386-018-0178-6] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 07/05/2018] [Accepted: 07/29/2018] [Indexed: 11/21/2022]
Abstract
Inhibitors of phosphodiesterase-4 (PDE4) have beneficial effects on memory in preclinical and clinical studies. Development of these drugs has stalled due to dose-limiting side effects of nausea and emesis. While use of subtype-selective inhibitors (i.e., for PDE4A, B, or D) could overcome this issue, conservation of the catalytic region, to which classical inhibitors bind, limits this approach. The present study examined the effects of BPN14770, an allosteric inhibitor of PDE4D, which binds to a primate-specific, N-terminal region. In mice engineered to express PDE4D with this primate-specific sequence, BPN14770 was 100-fold more potent for improving memory than in wild-type mice; meanwhile, it exhibited low potency in a mouse surrogate model for emesis. BPN14770 also antagonized the amnesic effects of scopolamine, increased cAMP signaling in brain, and increased BDNF and markers of neuronal plasticity associated with memory. These data establish a relationship between PDE4D target engagement and effects on memory for BPN14770 and suggest clinical potential for PDE4D-selective inhibitors.
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17
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Briet C, Pereda A, Le Stunff C, Motte E, de Dios Garcia-Diaz J, de Nanclares GP, Dumaz N, Silve C. Mutations causing acrodysostosis-2 facilitate activation of phosphodiesterase 4D3. Hum Mol Genet 2018; 26:3883-3894. [PMID: 29016851 DOI: 10.1093/hmg/ddx271] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Accepted: 07/08/2017] [Indexed: 01/21/2023] Open
Abstract
Type 2 acrodysostosis (ACRDYS2), a rare developmental skeletal dysplasia characterized by short stature, severe brachydactyly and facial dysostosis, is caused by mutations in the phosphodiesterase (PDE) 4D (PDE4D) gene. Several arguments suggest that the mutations should result in inappropriately increased PDE4D activity, however, no direct evidence supporting this hypothesis has been presented, and the functional consequences of the mutations remain unclear. We evaluated the impact of four different PDE4D mutations causing ACRDYS2 located in different functional domains on the activity of PDE4D3 expressed in Chinese hamster ovary cells. Three independent approaches were used: the direct measurement of PDE activity in cell lysates, the evaluation of intracellular cAMP levels using an EPAC-based (exchange factor directly activated by cAMP) bioluminescence resonance energy transfer sensor , and the assessment of PDE4D3 activation based on electrophoretic mobility. Our findings indicate that PDE4D3s carrying the ACRDYS2 mutations are more easily activated by protein kinase A-induced phosphorylation than WT PDE4D3. This occurs over a wide range of intracellular cAMP concentrations, including basal conditions, and result in increased hydrolytic activity. Our results provide new information concerning the mechanism whereby the mutations identified in the ACRDYS2 dysregulate PDE4D activity, and give insights into rare diseases involving the cAMP signaling pathway. These findings may offer new perspectives into the selection of specific PDE inhibitors and possible therapeutic intervention for these patients.
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Affiliation(s)
- Claire Briet
- INSERM U1169, Université Paris Sud, Hôpital Bicêtre, Le Kremlin Bicêtre, France.,Endocrinology, Diabetology and Nutrition, Mitovasc Institute, CHU Angers, France
| | - Arrate Pereda
- INSERM U1169, Université Paris Sud, Hôpital Bicêtre, Le Kremlin Bicêtre, France.,Molecular (Epi)Genetics Laboratory, BioAraba National Health Institute, OSI Araba-Txagorritxu, E-01009 Vitoria-Gasteiz, Spain
| | - Catherine Le Stunff
- INSERM U1169, Université Paris Sud, Hôpital Bicêtre, Le Kremlin Bicêtre, France
| | - Emmanuelle Motte
- INSERM U1169, Université Paris Sud, Hôpital Bicêtre, Le Kremlin Bicêtre, France.,Université Versailles - St Quentin, UFR des Sciences de la santé Simone Veil, Versailles, Paris, France
| | - Juan de Dios Garcia-Diaz
- Clinical Genetics Unit, Department of Internal Medicine, University Hospital Príncipe de Asturias, Alcalá de Henares, Madrid, Spain
| | - Guiomar Perez de Nanclares
- Molecular (Epi)Genetics Laboratory, BioAraba National Health Institute, OSI Araba-Txagorritxu, E-01009 Vitoria-Gasteiz, Spain
| | - Nicolas Dumaz
- INSERM U976, Institut de Recherche sur la Peau, Hôpital Saint Louis, Paris, France
| | - Caroline Silve
- INSERM U1169, Université Paris Sud, Hôpital Bicêtre, Le Kremlin Bicêtre, France.,Centre de Référence des Maladies Rares du Métabolisme du Phosphore et du Calcium/Filière de Santé Maladies Rares OSCAR, Assistance Publique Hôpitaux de Paris, Paris, France.,Service de Biochimie et Génétique Moléculaires, Assistance Publique Hôpitaux de Paris, Hôpital Cochin, Paris, France
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18
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Hansen RT, Zhang HT. The Past, Present, and Future of Phosphodiesterase-4 Modulation for Age-Induced Memory Loss. ADVANCES IN NEUROBIOLOGY 2018; 17:169-199. [PMID: 28956333 DOI: 10.1007/978-3-319-58811-7_7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The purpose of this chapter is to highlight the state of progress for phosphodiesterase-4 (PDE4) modulation as a potential therapeutic for psychiatric illness, and to draw attention to particular hurdles and obstacles that must be overcome in future studies to develop PDE4-mediated therapeutics. Pathological and non-pathological related memory loss will be the focus of the chapter; however, we will at times also touch upon other psychiatric illnesses like anxiety and depression. First, we will provide a brief background of PDE4, and the rationale for its extensive study in cognition. Second, we will explore fundamental differences in individual PDE4 subtypes, and then begin to address differences between pathological and non-pathological aging. Alterations of cAMP/PDE4 signaling that occur within normal vs. pathological aging, and the potential for PDE4 modulation to combat these alterations within each context will be described. Finally, we will finish the chapter with obstacles that have hindered the field, and future studies and alternative viewpoints that need to be addressed. Overall, we hope this chapter will demonstrate the incredible complexity of PDE4 signaling in the brain, and will be useful in forming a strategy to develop future PDE4-mediated therapeutics for psychiatric illnesses.
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Affiliation(s)
- Rolf T Hansen
- Departments of Behavioral Medicine & Psychiatry and Physiology & Pharmacology, West Virginia University Health Sciences Center, 1 Medical Center Drive, Morgantown, WV, 26506-9137, USA
| | - Han-Ting Zhang
- Department of Behavioral Medicine and Psychiatry, West Virginia University Health Sciences Center, 1 Medical Center Drive, Morgantown, WV, 26506, USA. .,Department of Physiology and Pharmacology, West Virginia University Health Sciences Center, 1 Medical Center Drive, Morgantown, WV, 26506, USA. .,Institute of Pharmacology, Taishan Medical University, Taian, 271016, China.
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19
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Phosphodiesterase Diversity and Signal Processing Within cAMP Signaling Networks. ADVANCES IN NEUROBIOLOGY 2018; 17:3-14. [PMID: 28956327 DOI: 10.1007/978-3-319-58811-7_1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A large number of neuromodulators activate G-protein coupled receptors (GPCRs) and mediate their cellular actions via the regulation of intracellular cAMP, the small highly diffusible second messenger. In fact, in the same neuron several different GPCRs can regulate cAMP with seemingly identical timecourses that give rise to distinct signaling outcomes, suggesting that cAMP does not have equivalent access to all its downstream effectors and may exist within defined intracellular pools or domains. cAMP compartmentalization is the process that allows the neuron to differentially interpret these various intracellular cAMP signals into cellular response. The molecular mechanisms that give rise to cAMP compartmentalization are not fully understood, but it is thought that phosphodiesterases (PDEs), the enzymes that degrade cAMP, significantly contribute to this process. PDEs, as the sole mechanism of signal termination for cAMP, hold great promise as therapeutic targets for pathologies that are due to the dysregulation of intracellular cAMP signaling. Due to their diverse catalytic activity, regulation and localization each PDE subtype expressed in a given neuron may have a distinct role on downstream signaling.
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20
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Campbell SL, van Groen T, Kadish I, Smoot LHM, Bolger GB. Altered phosphorylation, electrophysiology, and behavior on attenuation of PDE4B action in hippocampus. BMC Neurosci 2017; 18:77. [PMID: 29197324 PMCID: PMC5712142 DOI: 10.1186/s12868-017-0396-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Accepted: 11/28/2017] [Indexed: 01/19/2023] Open
Abstract
Background PDE4 cyclic nucleotide phosphodiesterases regulate 3′, 5′ cAMP abundance in the CNS and thereby regulate PKA activity and phosphorylation of CREB, which has been implicated in learning and memory, depression and other functions. The PDE4 isoform PDE4B1 also interacts with the DISC1 protein, implicated in neural development and behavioral disorders. The cellular functions of PDE4B1 have been investigated extensively, but its function(s) in the intact organism remained unexplored. Results To specifically disrupt PDE4B1, we developed mice that express a PDE4B1-D564A transgene in the hippocampus and forebrain. The transgenic mice showed enhanced phosphorylation of CREB and ERK1/2 in hippocampus. Hippocampal neurogenesis was increased in the transgenic mice. Hippocampal electrophysiological studies showed increased baseline synaptic transmission and enhanced LTP in male transgenic mice. Behaviorally, male transgenic mice showed increased activity in prolonged open field testing, but neither male nor female transgenic mice showed detectable anxiety-like behavior or antidepressant effects in the elevated plus-maze, tail-suspension or forced-swim tests. Neither sex showed any significant differences in associative fear conditioning or showed any demonstrable abnormalities in pre-pulse inhibition. Conclusions These data support the use of an isoform-selective approach to the study of PDE4B1 function in the CNS and suggest a probable role of PDE4B1 in synaptic plasticity and behavior. They also provide additional rationale and a refined approach to the development of small-molecule PDE4B1-selective inhibitors, which have potential functions in disorders of cognition, memory, mood and affect.
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Affiliation(s)
- Susan L Campbell
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA.,Center for Glial Biology in Health, Disease, and Cancer, Virginia Tech Carilion Research Institute, 2 Riverside Circle, Roanoke, VA, 24016, USA
| | - Thomas van Groen
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - Inga Kadish
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - Lisa High Mitchell Smoot
- Department of Medicine, University of Alabama at Birmingham, NP 2501, 1720 2nd Ave S, Birmingham, AL, 35294-3300, USA
| | - Graeme B Bolger
- Department of Pharmacology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA. .,Department of Medicine, University of Alabama at Birmingham, NP 2501, 1720 2nd Ave S, Birmingham, AL, 35294-3300, USA. .,Center for Glial Biology in Health, Disease, and Cancer, Virginia Tech Carilion Research Institute, 2 Riverside Circle, Roanoke, VA, 24016, USA.
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21
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Perera RK, Fischer TH, Wagner M, Dewenter M, Vettel C, Bork NI, Maier LS, Conti M, Wess J, El-Armouche A, Hasenfuß G, Nikolaev VO. Atropine augments cardiac contractility by inhibiting cAMP-specific phosphodiesterase type 4. Sci Rep 2017; 7:15222. [PMID: 29123207 PMCID: PMC5680190 DOI: 10.1038/s41598-017-15632-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 10/31/2017] [Indexed: 01/21/2023] Open
Abstract
Atropine is a clinically relevant anticholinergic drug, which blocks inhibitory effects of the parasympathetic neurotransmitter acetylcholine on heart rate leading to tachycardia. However, many cardiac effects of atropine cannot be adequately explained solely by its antagonism at muscarinic receptors. In isolated mouse ventricular cardiomyocytes expressing a Förster resonance energy transfer (FRET)-based cAMP biosensor, we confirmed that atropine inhibited acetylcholine-induced decreases in cAMP. Unexpectedly, even in the absence of acetylcholine, after G-protein inactivation with pertussis toxin or in myocytes from M2- or M1/3-muscarinic receptor knockout mice, atropine increased cAMP levels that were pre-elevated with the β-adrenergic agonist isoproterenol. Using the FRET approach and in vitro phosphodiesterase (PDE) activity assays, we show that atropine acts as an allosteric PDE type 4 (PDE4) inhibitor. In human atrial myocardium and in both intact wildtype and M2 or M1/3-receptor knockout mouse Langendorff hearts, atropine led to increased contractility and heart rates, respectively. In vivo, the atropine-dependent prolongation of heart rate increase was blunted in PDE4D but not in wildtype or PDE4B knockout mice. We propose that inhibition of PDE4 by atropine accounts, at least in part, for the induction of tachycardia and the arrhythmogenic potency of this drug.
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Affiliation(s)
- Ruwan K Perera
- Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Clinic of Cardiology and Pulmonology, Heart Research Center Göttingen, Georg August University Medical Center, Göttingen, Germany
| | - Thomas H Fischer
- Clinic of Cardiology and Pulmonology, Heart Research Center Göttingen, Georg August University Medical Center, Göttingen, Germany
| | - Michael Wagner
- Institute of Pharmacology and Toxicology, Technical University of Dresden, Dresden, Germany
| | - Matthias Dewenter
- Institute of Pharmacology and Toxicology, Technical University of Dresden, Dresden, Germany
| | - Christiane Vettel
- Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty, Heidelberg University, Mannheim, Germany
| | - Nadja I Bork
- Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK, German Center for Cardiovascular Research, partner sites Hamburg/Kiel/Lübeck and Göttingen, Hamburg, Germany
| | - Lars S Maier
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Marco Conti
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, United States
| | - Juergen Wess
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), Bethesda, Maryland, USA
| | - Ali El-Armouche
- Institute of Pharmacology and Toxicology, Technical University of Dresden, Dresden, Germany
| | - Gerd Hasenfuß
- Clinic of Cardiology and Pulmonology, Heart Research Center Göttingen, Georg August University Medical Center, Göttingen, Germany.,DZHK, German Center for Cardiovascular Research, partner sites Hamburg/Kiel/Lübeck and Göttingen, Hamburg, Germany
| | - Viacheslav O Nikolaev
- Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. .,DZHK, German Center for Cardiovascular Research, partner sites Hamburg/Kiel/Lübeck and Göttingen, Hamburg, Germany.
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22
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Long T, Rojo-Arreola L, Shi D, El-Sakkary N, Jarnagin K, Rock F, Meewan M, Rascón AA, Lin L, Cunningham KA, Lemieux GA, Podust L, Abagyan R, Ashrafi K, McKerrow JH, Caffrey CR. Phenotypic, chemical and functional characterization of cyclic nucleotide phosphodiesterase 4 (PDE4) as a potential anthelmintic drug target. PLoS Negl Trop Dis 2017; 11:e0005680. [PMID: 28704396 PMCID: PMC5526615 DOI: 10.1371/journal.pntd.0005680] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 07/25/2017] [Accepted: 06/04/2017] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Reliance on just one drug to treat the prevalent tropical disease, schistosomiasis, spurs the search for new drugs and drug targets. Inhibitors of human cyclic nucleotide phosphodiesterases (huPDEs), including PDE4, are under development as novel drugs to treat a range of chronic indications including asthma, chronic obstructive pulmonary disease and Alzheimer's disease. One class of huPDE4 inhibitors that has yielded marketed drugs is the benzoxaboroles (Anacor Pharmaceuticals). METHODOLOGY/PRINCIPAL FINDINGS A phenotypic screen involving Schistosoma mansoni and 1,085 benzoxaboroles identified a subset of huPDE4 inhibitors that induced parasite hypermotility and degeneration. To uncover the putative schistosome PDE4 target, we characterized four PDE4 sequences (SmPDE4A-D) in the parasite's genome and transcriptome, and cloned and recombinantly expressed the catalytic domain of SmPDE4A. Among a set of benzoxaboroles and catechol inhibitors that differentially inhibit huPDE4, a relationship between the inhibition of SmPDE4A, and parasite hypermotility and degeneration, was measured. To validate SmPDE4A as the benzoxaborole molecular target, we first generated Caenorhabditis elegans lines that express a cDNA for smpde4a on a pde4(ce268) mutant (hypermotile) background: the smpde4a transgene restored mutant worm motility to that of the wild type. We then showed that benzoxaborole inhibitors of SmPDE4A that induce hypermotility in the schistosome also elicit a hypermotile response in the C. elegans lines that express the smpde4a transgene, thereby confirming SmPDE4A as the relevant target. CONCLUSIONS/SIGNIFICANCE The orthogonal chemical, biological and genetic strategies employed identify SmPDE4A's contribution to parasite motility and degeneration, and its potential as a drug target. Transgenic C. elegans is highlighted as a potential screening tool to optimize small molecule chemistries to flatworm molecular drug targets.
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Affiliation(s)
- Thavy Long
- Center for Discovery and Innovation in Parasitic Diseases, University of California San Francisco, San Francisco, California, United States of America
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
| | - Liliana Rojo-Arreola
- Center for Discovery and Innovation in Parasitic Diseases, University of California San Francisco, San Francisco, California, United States of America
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
| | - Da Shi
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Nelly El-Sakkary
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Kurt Jarnagin
- Anacor Pharmaceuticals, Inc., Palo Alto, California, United States of America
| | - Fernando Rock
- Anacor Pharmaceuticals, Inc., Palo Alto, California, United States of America
| | - Maliwan Meewan
- Anacor Pharmaceuticals, Inc., Palo Alto, California, United States of America
| | - Alberto A. Rascón
- Center for Discovery and Innovation in Parasitic Diseases, University of California San Francisco, San Francisco, California, United States of America
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
| | - Lin Lin
- Department of Physiology, University of California San Francisco, San Francisco, California, United States of America
| | - Katherine A. Cunningham
- Department of Physiology, University of California San Francisco, San Francisco, California, United States of America
| | - George A. Lemieux
- Department of Physiology, University of California San Francisco, San Francisco, California, United States of America
| | - Larissa Podust
- Center for Discovery and Innovation in Parasitic Diseases, University of California San Francisco, San Francisco, California, United States of America
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
| | - Ruben Abagyan
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Kaveh Ashrafi
- Department of Physiology, University of California San Francisco, San Francisco, California, United States of America
| | - James H. McKerrow
- Center for Discovery and Innovation in Parasitic Diseases, University of California San Francisco, San Francisco, California, United States of America
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
| | - Conor R. Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, University of California San Francisco, San Francisco, California, United States of America
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
- * E-mail:
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PDE4 Inhibition and Inflammatory Bowel Disease: A Novel Therapeutic Avenue. Int J Mol Sci 2017; 18:ijms18061276. [PMID: 28617319 PMCID: PMC5486098 DOI: 10.3390/ijms18061276] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 06/01/2017] [Accepted: 06/09/2017] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND In the last few decades, a better knowledge of the inflammatory pathways involved in the pathogenesis of Inflammatory Bowel Disease (IBD) has promoted biological therapy as an important tool to treat IBD patients. However, in spite of a wider spectrum of biological drugs, a significant proportion of patients is unaffected by or lose their response to these compounds, along with increased risks of infections and malignancies. For these reasons there is an urgent need to look for new pharmacological targets. The novel Phosphodiesterase 4 (PDE4) inhibitors have been recently introduced as new modulators of intracellular signals and gene transcription for the treatment of IBD. AIM To discuss and describe the state of the art of this new class of compounds in the IBD field, with particular attention to apremilast. METHODS Published articles selected from PubMed were comprehensively reviewed, with key words including apremilast, inflammatory disease, IBD, psoriasis, psoriatic arthritis, pathogenesis, therapies, and treatment. RESULTS PDE4 inhibitors generate elevated intracellular levels of cyclic Adenosine Monophosphate (cAMP), that consequently down-regulate the release of pro-inflammatory cytokines in the mucosa of IBD patients. The newly developed apremilast is one of these drugs and has already been approved for the treatment of dermatologic/rheumatologic inflammatory conditions; studies in psoriasis and psoriatic arthritis have in fact demonstrated its clinical activity. However, no clinical trials have yet been published on the use of apremilast in IBD. CONCLUSION In light of the similarity of pro-inflammatory signaling pathways across the gut, the skin, and joints, apremilast is likely supposed to show its efficacy also in IBD.
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Knott EP, Assi M, Rao SNR, Ghosh M, Pearse DD. Phosphodiesterase Inhibitors as a Therapeutic Approach to Neuroprotection and Repair. Int J Mol Sci 2017; 18:E696. [PMID: 28338622 PMCID: PMC5412282 DOI: 10.3390/ijms18040696] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 03/10/2017] [Accepted: 03/15/2017] [Indexed: 12/21/2022] Open
Abstract
A wide diversity of perturbations of the central nervous system (CNS) result in structural damage to the neuroarchitecture and cellular defects, which in turn are accompanied by neurological dysfunction and abortive endogenous neurorepair. Altering intracellular signaling pathways involved in inflammation and immune regulation, neural cell death, axon plasticity and remyelination has shown therapeutic benefit in experimental models of neurological disease and trauma. The second messengers, cyclic adenosine monophosphate (cyclic AMP) and cyclic guanosine monophosphate (cyclic GMP), are two such intracellular signaling targets, the elevation of which has produced beneficial cellular effects within a range of CNS pathologies. The only known negative regulators of cyclic nucleotides are a family of enzymes called phosphodiesterases (PDEs) that hydrolyze cyclic nucleotides into adenosine monophosphate (AMP) or guanylate monophosphate (GMP). Herein, we discuss the structure and physiological function as well as the roles PDEs play in pathological processes of the diseased or injured CNS. Further we review the approaches that have been employed therapeutically in experimental paradigms to block PDE expression or activity and in turn elevate cyclic nucleotide levels to mediate neuroprotection or neurorepair as well as discuss both the translational pathway and current limitations in moving new PDE-targeted therapies to the clinic.
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Affiliation(s)
- Eric P Knott
- Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA.
| | - Mazen Assi
- The Miami Project to Cure Paralysis, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
| | - Sudheendra N R Rao
- The Miami Project to Cure Paralysis, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
| | - Mousumi Ghosh
- The Miami Project to Cure Paralysis, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
- The Department of Neurological Surgery, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
| | - Damien D Pearse
- The Miami Project to Cure Paralysis, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
- The Department of Neurological Surgery, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
- The Neuroscience Program, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
- The Interdisciplinary Stem Cell Institute, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
- Bruce Wayne Carter Department of Veterans Affairs Medical Center, Miami, FL 33136, USA.
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25
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Bolger GB. The RNA-binding protein SERBP1 interacts selectively with the signaling protein RACK1. Cell Signal 2017; 35:256-263. [PMID: 28267599 DOI: 10.1016/j.cellsig.2017.03.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Revised: 02/23/2017] [Accepted: 03/02/2017] [Indexed: 12/19/2022]
Abstract
The RACK1 protein interacts with numerous proteins involved in signal transduction, the cytoskeleton, and mRNA splicing and translation. We used the 2-hybrid system to identify additional proteins interacting with RACK1 and isolated the RNA-binding protein SERBP1. SERPB1 shares amino acid sequence homology with HABP4 (also known as Ki-1/57), a component of the RNA spicing machinery that has been shown previously to interact with RACK1. Several different isoforms of SERBP1, generated by alternative mRNA splicing, interacted with RACK1 with indistinguishable interaction strength, as determined by a 2-hybrid beta-galactosidase assay. Analysis of deletion constructs of SERBP1 showed that the C-terminal third of the SERBP1 protein, which contains one of its two substrate sites for protein arginine N-methyltransferase 1 (PRMT1), is necessary and sufficient for it to interact with RACK1. Analysis of single amino acid substitutions in RACK1, identified in a reverse 2-hybrid screen, showed very substantial overlap with those implicated in the interaction of RACK1 with the cAMP-selective phosphodiesterase PDE4D5. These data are consistent with SERBP1 interacting selectively with RACK1, mediated by an extensive interaction surface on both proteins.
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Affiliation(s)
- Graeme B Bolger
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294-3300, USA; Department of Pharmacology, University of Alabama at Birmingham, Birmingham, AL 35294-3300, USA.
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26
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Bolger GB. The PDE4 cAMP-Specific Phosphodiesterases: Targets for Drugs with Antidepressant and Memory-Enhancing Action. ADVANCES IN NEUROBIOLOGY 2017; 17:63-102. [PMID: 28956330 DOI: 10.1007/978-3-319-58811-7_4] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The PDE4 cyclic nucleotide phosphodiesterases are essential regulators of cAMP abundance in the CNS through their ability to regulate PKA activity, the phosphorylation of CREB, and other important elements of signal transduction. In pre-clinical models and in early-stage clinical trials, PDE4 inhibitors have been shown to have antidepressant and memory-enhancing activity. However, the development of clinically-useful PDE4 inhibitors for CNS disorders has been limited by variable efficacy and significant side effects. Recent structural studies have greatly enhanced our understanding of the molecular configuration of PDE4 enzymes, especially the "long" PDE4 isoforms that are abundant in the CNS. The new structural data provide a rationale for the development of a new generation of PDE4 inhibitors that specifically act on long PDE4 isoforms. These next generation PDE4 inhibitors may also be capable of targeting the interactions of select long forms with their "partner" proteins, such as RACK1, β-arrestin, and DISC1. They would therefore have the ability to affect cAMP levels in specific cellular compartments and target localized cellular functions, such as synaptic plasticity. These new agents might also be able to target PDE4 populations in select regions of the CNS that are implicated in learning and memory, affect, and cognition. Potential therapeutic uses of these agents could include affective disorders, memory enhancement, and neurogenesis.
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Affiliation(s)
- Graeme B Bolger
- Departments of Medicine and Pharmacology, University of Alabama at Birmingham, 1720 2nd Avenue South, NP 2501, Birmingham, AL, 35294-3300, USA.
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27
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Subcellular Targeting of PDE4 in Cardiac Myocytes and Generation of Signaling Compartments. MICRODOMAINS IN THE CARDIOVASCULAR SYSTEM 2017. [DOI: 10.1007/978-3-319-54579-0_8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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28
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D'Ursi P, Guariento S, Trombetti G, Orro A, Cichero E, Milanesi L, Fossa P, Bruno O. Further Insights in the Binding Mode of Selective Inhibitors to Human PDE4D Enzyme Combining Docking and Molecular Dynamics. Mol Inform 2016; 35:369-81. [PMID: 27546041 PMCID: PMC5094559 DOI: 10.1002/minf.201501033] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 05/19/2016] [Indexed: 12/18/2022]
Abstract
Alzheimer's disease has recently emerged as a possible field of application for PDE4D inhibitors (PDE4DIs). The great structure similarity among the various PDE4 isoforms and, furthermore, the lack of the full length crystal structure of the enzyme, impaired the rational design of new selective PDE4DIs. In this paper, with the aim of exploring new insights into the PDE4D binding, we tackled the problem by performing a computational study based on docking simulations combined with molecular dynamics (D-MD). Our work uniquely identified the binding mode and the key residues involved in the interaction with a number of in-house catechol iminoether derivatives, acting as PDE4DIs. Moreover, the new binding mode was tested using a series of analogues previously reported by us and it was used to confirm their key structural features to allow PDE4D inhibition. The binding model disclosed within the current computational study may prove to be useful to further advance the design and synthesis of novel, more potent and selective, PDE4D inhibitors.
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Affiliation(s)
- Pasqualina D'Ursi
- Institute for Biomedical Technologies e National Research Council (ITB-CNR), Via Fratelli Cervi 93, 20090, Segrate (MI, Italy
| | - Sara Guariento
- Department of Pharmacy, Section of Medicinal Chemistry, School of Medical and Pharmaceutical Sciences, University of Genoa, Viale Benedetto XV 3, 16132, Genova (GE, Italy
| | - Gabriele Trombetti
- Institute for Biomedical Technologies e National Research Council (ITB-CNR), Via Fratelli Cervi 93, 20090, Segrate (MI, Italy
| | - Alessandro Orro
- Institute for Biomedical Technologies e National Research Council (ITB-CNR), Via Fratelli Cervi 93, 20090, Segrate (MI, Italy
| | - Elena Cichero
- Department of Pharmacy, Section of Medicinal Chemistry, School of Medical and Pharmaceutical Sciences, University of Genoa, Viale Benedetto XV 3, 16132, Genova (GE, Italy
| | - Luciano Milanesi
- Institute for Biomedical Technologies e National Research Council (ITB-CNR), Via Fratelli Cervi 93, 20090, Segrate (MI, Italy
| | - Paola Fossa
- Department of Pharmacy, Section of Medicinal Chemistry, School of Medical and Pharmaceutical Sciences, University of Genoa, Viale Benedetto XV 3, 16132, Genova (GE, Italy .
| | - Olga Bruno
- Department of Pharmacy, Section of Medicinal Chemistry, School of Medical and Pharmaceutical Sciences, University of Genoa, Viale Benedetto XV 3, 16132, Genova (GE, Italy
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New insights into selective PDE4D inhibitors: 3-(Cyclopentyloxy)-4-methoxybenzaldehyde O-(2-(2,6-dimethylmorpholino)-2-oxoethyl) oxime (GEBR-7b) structural development and promising activities to restore memory impairment. Eur J Med Chem 2016; 124:82-102. [PMID: 27560284 DOI: 10.1016/j.ejmech.2016.08.018] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 08/09/2016] [Accepted: 08/10/2016] [Indexed: 12/11/2022]
Abstract
Phosphodiesterase type 4D (PDE4D) has been indicated as a promising target for treating neurodegenerative pathologies such as Alzheimer's Disease (AD). By preventing cAMP hydrolysis, PDE4 inhibitors (PDE4Is) increase the cAMP response element-binding protein (CREB) phosphorylation, synaptic plasticity and long-term memory formation. Pharmacological and behavioral studies on our hit GEBR-7b demonstrated that selective PDE4DIs could improve memory without causing emesis and sedation. The hit development led to new molecule series, herein reported, characterized by a catechol structure bonded to five member heterocycles. Molecular modeling studies highlighted the pivotal role of a polar alkyl chain in conferring selective enzyme interaction. Compound 8a showed PDE4D3 selective inhibition and was able to increase intracellular cAMP levels in neuronal cells, as well as in the hippocampus of freely moving rats. Furthermore, 8a was able to readily cross the blood-brain barrier and enhanced memory performance in mice without causing any emetic-like behavior. These data support the view that PDE4D is an adequate molecular target to restore memory deficits in different neuropathologies, including AD, and also indicate compound 8a as a promising candidate for further preclinical development.
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30
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Bolger GB. RACK1 and β-arrestin2 attenuate dimerization of PDE4 cAMP phosphodiesterase PDE4D5. Cell Signal 2016; 28:706-12. [PMID: 26257302 PMCID: PMC4744576 DOI: 10.1016/j.cellsig.2015.08.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 08/05/2015] [Indexed: 01/14/2023]
Abstract
PDE4 family cAMP-selective cyclic nucleotide phosphodiesterases are important in the regulation of cAMP abundance in numerous systems, and thereby play an important role in the regulation of PKA and EPAC activity and the phosphorylation of CREB. We have used the yeast 2-hybrid system to demonstrate recently that long PDE4 isoforms form homodimers, consistent with data obtained recently by structural studies. The long PDE4 isoform PDE4D5 interacts selectively with β-arrestin2, implicated in the regulation of G-protein-coupled receptors and other cell signaling components, and also with the β-propeller protein RACK1. In the present study, we use 2-hybrid approaches to demonstrate that RACK1 and β-arrestin2 inhibit the dimerization of PDE4D5. We also show that serine-to-alanine mutations at PKA and ERK1/2 phosphorylation sites on PDE4D5 detectably ablate dimerization. Conversely, phospho-mimic serine-to-aspartate mutations at the MK2 and oxidative stress kinase sites ablate dimerization. Analysis of PDE4D5 that is locked into the dimeric configuration by the formation of a trans disulfide bond between Ser261 and Ser602 shows that RACK1 interacts strongly with both the monomeric and dimeric forms, but that β-arrestin2 interacts exclusively with the monomeric form. This is consistent with the concept that β-arrestin2 can preferentially recruit the monomeric, or "open," form of PDE4D5 to β2-adrenergic receptors, where it can regulate cAMP signaling.
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Affiliation(s)
- Graeme B Bolger
- Departments of Medicine and Pharmacology, University of Alabama at Birmingham, Birmingham AL 35294, USA.
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31
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PDE4D phosphorylation: A coincidence detector integrating multiple signaling pathways. Cell Signal 2015; 28:719-24. [PMID: 26562185 DOI: 10.1016/j.cellsig.2015.11.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 11/02/2015] [Indexed: 11/24/2022]
Abstract
In Eukaryotes, more than 100 different phosphodiesterase (PDE) proteins serve to fine-tune cyclic nucleotide (cAMP and cGMP) signals and contribute to specificity of signaling. In mammals, PDEs are divided into 11 families, of which PDE4 represents the largest family. Four genes (pde4a, pde4b, pde4c and pde4d) encode for this class of enzymes in mammals and give rise to more than 20 variants. Within this family of genes, PDE4D was discovered on the basis of its regulatory properties and its induction by hormones and cAMP. PDE4D has often been used as the prototype PDE4 and large body of work has been generated on the biochemical, pharmacological, and physiological properties of this enzyme. This review covers the regulation of PDE4D by phosphorylation, the impact of this regulation in the context of the structure of this protein, and the functional consequences of this complex pattern of posttranslational modifications.
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32
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Engineered stabilization and structural analysis of the autoinhibited conformation of PDE4. Proc Natl Acad Sci U S A 2015; 112:E1414-22. [PMID: 25775568 DOI: 10.1073/pnas.1419906112] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Phosphodiesterase 4 (PDE4) is an essential contributor to intracellular signaling and an important drug target. The four members of this enzyme family (PDE4A to -D) are functional dimers in which each subunit contains two upstream conserved regions (UCR), UCR1 and -2, which precede the C-terminal catalytic domain. Alternative promoters, transcriptional start sites, and mRNA splicing lead to the existence of over 25 variants of PDE4, broadly classified as long, short, and supershort forms. We report the X-ray crystal structure of long form PDE4B containing UCR1, UCR2, and the catalytic domain, crystallized as a dimer in which a disulfide bond cross-links cysteines engineered into UCR2 and the catalytic domain. Biochemical and mass spectrometric analyses showed that the UCR2-catalytic domain interaction occurs in trans, and established that this interaction regulates the catalytic activity of PDE4. By elucidating the key structural determinants of dimerization, we show that only long forms of PDE4 can be regulated by this mechanism. The results also provide a structural basis for the long-standing observation of high- and low-affinity binding sites for the prototypic inhibitor rolipram.
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33
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Gurney ME, D'Amato EC, Burgin AB. Phosphodiesterase-4 (PDE4) molecular pharmacology and Alzheimer's disease. Neurotherapeutics 2015; 12:49-56. [PMID: 25371167 PMCID: PMC4322084 DOI: 10.1007/s13311-014-0309-7] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Between 20% and 25% of patients diagnosed with Alzheimer's disease (AD) do not have amyloid burden as assessed by positron emission tomography imaging. Thus, there is a need for nonamyloid-directed therapies for AD, especially for those patients with non-amyloid AD. The family of phosphodiesterase-4 (PDE4) enzymes are underexploited therapeutic targets for central nervous system indications. While the PDE4A, B, and D subtypes are expressed in brain, the strict amino acid sequence conservation of the active site across the four subtypes of PDE4 has made it difficult to discover subtype inhibitors. The recent elucidation of the structure of the PDE4 N- and C-terminal regulatory domains now makes it possible to design subtype-selective, negative allosteric modulators (PDE4-NAMs). These act through closing the N-terminal UCR2 or C-terminal CR3 regulatory domains, and thereby inhibit the enzyme by blocking access of cyclic adenosine monophosphate (cAMP) to the active site. PDE4B-NAMs have the potential to reduce neuroinflammation by dampening microglia cytokine production triggered by brain amyloid, while PDE4D-NAMs have potent cognitive benefit by augmenting signaling through the cAMP/protein kinase A/cAMP response element-binding protein (CREB) pathway for memory consolidation. The importance of PDE4D for human cognition is underscored by the recent discovery of PDE4D mutations in acrodysostosis (ACRDY2: MIM 600129), an ultra rare disorder associated with intellectual disability. Thus, the family of PDE4 enzymes provides rich opportunities for the development of mechanistically novel drugs to treat neuroinflammation or the cognitive deficits in AD.
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34
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Bolger GB, Dunlop AJ, Meng D, Day JP, Klussmann E, Baillie GS, Adams DR, Houslay MD. Dimerization of cAMP phosphodiesterase-4 (PDE4) in living cells requires interfaces located in both the UCR1 and catalytic unit domains. Cell Signal 2014; 27:756-69. [PMID: 25546709 PMCID: PMC4371794 DOI: 10.1016/j.cellsig.2014.12.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 12/16/2014] [Indexed: 02/08/2023]
Abstract
PDE4 family cAMP phosphodiesterases play a pivotal role in determining compartmentalised cAMP signalling through targeted cAMP breakdown. Expressing the widely found PDE4D5 isoform, as both bait and prey in a yeast 2-hybrid system, we demonstrated interaction consistent with the notion that long PDE4 isoforms form dimers. Four potential dimerization sites were uncovered using a scanning peptide array approach, where a recombinant purified PDE4D5 fusion protein was used to probe a 25-mer library of overlapping peptides covering the entire PDE4D5 sequence. Key residues involved in PDE4D5 dimerization were defined using a site-directed mutagenesis programme directed by an alanine scanning peptide array approach. Critical residues stabilising PDE4D5 dimerization were defined within the regulatory UCR1 region found in long, but not short, PDE4 isoforms, namely the Arg173, Asn174 and Asn175 (DD1) cluster. Disruption of the DD1 cluster was not sufficient, in itself, to destabilise PDE4D5 homodimers. Instead, disruption of an additional interface, located on the PDE4 catalytic unit, was also required to convert PDE4D5 into a monomeric form. This second dimerization site on the conserved PDE4 catalytic unit is dependent upon a critical ion pair interaction. This involves Asp463 and Arg499 in PDE4D5, which interact in a trans fashion involving the two PDE4D5 molecules participating in the homodimer. PDE4 long isoforms adopt a dimeric state in living cells that is underpinned by two key contributory interactions, one involving the UCR modules and one involving an interface on the core catalytic domain. We propose that short forms do not adopt a dimeric configuration because, in the absence of the UCR1 module, residual engagement of the remaining core catalytic domain interface provides insufficient free energy to drive dimerization. The functioning of PDE4 long and short forms is thus poised to be inherently distinct due to this difference in quaternary structure. In a yeast 2-hybrid system we show that long PDE4 isoforms dimerize. Scanning peptide array and mutagenesis located two dimerization surfaces. One surface maps to the regulatory UCR1 region found only in long forms. A second locates to the core catalytic domain. PDE4 long and short forms differ in quaternary structure.
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Affiliation(s)
- Graeme B Bolger
- Departments of Medicine and Pharmacology, University of Alabama, Birmingham, AL 35294, USA
| | - Allan J Dunlop
- Institute of Cardiovascular and Medical Science, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - Dong Meng
- Institute of Cardiovascular and Medical Science, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - Jon P Day
- Institute of Cardiovascular and Medical Science, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - Enno Klussmann
- Max Delbrueck Center for Molecular Medicine, German Centre for Cardiovascular Research (DZHK), Berlin, Germany
| | - George S Baillie
- Institute of Cardiovascular and Medical Science, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - David R Adams
- Institute of Chemical Sciences, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, Scotland, United Kingdom
| | - Miles D Houslay
- Institute of Pharmaceutical Sciences, King's College London, London SE1 9NH, United Kingdom.
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35
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Ahmad F, Murata T, Shimizu K, Degerman E, Maurice D, Manganiello V. Cyclic nucleotide phosphodiesterases: important signaling modulators and therapeutic targets. Oral Dis 2014; 21:e25-50. [PMID: 25056711 DOI: 10.1111/odi.12275] [Citation(s) in RCA: 107] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 07/09/2014] [Indexed: 02/06/2023]
Abstract
By catalyzing hydrolysis of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), cyclic nucleotide phosphodiesterases are critical regulators of their intracellular concentrations and their biological effects. As these intracellular second messengers control many cellular homeostatic processes, dysregulation of their signals and signaling pathways initiate or modulate pathophysiological pathways related to various disease states, including erectile dysfunction, pulmonary hypertension, acute refractory cardiac failure, intermittent claudication, chronic obstructive pulmonary disease, and psoriasis. Alterations in expression of PDEs and PDE-gene mutations (especially mutations in PDE6, PDE8B, PDE11A, and PDE4) have been implicated in various diseases and cancer pathologies. PDEs also play important role in formation and function of multimolecular signaling/regulatory complexes, called signalosomes. At specific intracellular locations, individual PDEs, together with pathway-specific signaling molecules, regulators, and effectors, are incorporated into specific signalosomes, where they facilitate and regulate compartmentalization of cyclic nucleotide signaling pathways and specific cellular functions. Currently, only a limited number of PDE inhibitors (PDE3, PDE4, PDE5 inhibitors) are used in clinical practice. Future paths to novel drug discovery include the crystal structure-based design approach, which has resulted in generation of more effective family-selective inhibitors, as well as burgeoning development of strategies to alter compartmentalized cyclic nucleotide signaling pathways by selectively targeting individual PDEs and their signalosome partners.
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Affiliation(s)
- F Ahmad
- Cardiovascular and Pulmonary Branch, National Heart, Lung and Blood Institute, Bethesda, MD, USA
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36
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Kim KH, Jun YW, Park Y, Lee JA, Suh BC, Lim CS, Lee YS, Kaang BK, Jang DJ. Intracellular membrane association of the Aplysia cAMP phosphodiesterase long and short forms via different targeting mechanisms. J Biol Chem 2014; 289:25797-811. [PMID: 25077971 DOI: 10.1074/jbc.m114.572222] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Phosphodiesterases (PDEs) play key roles in cAMP compartmentalization, which is required for intracellular signaling processes, through specific subcellular targeting. Previously, we showed that the long and short forms of Aplysia PDE4 (ApPDE4), which are localized to the membranes of distinct subcellular organelles, play key roles in 5-hydroxytryptamine-induced synaptic facilitation in Aplysia sensory and motor synapses. However, the molecular mechanism of the isoform-specific distinct membrane targeting was not clear. In this study, we further investigated the molecular mechanism of the membrane targeting of the ApPDE4 long and short forms. We found that the membrane targeting of the long form was mediated by hydrophobic interactions, mainly via 16 amino acids at the N-terminal region, whereas the short form was targeted solely to the plasma membrane, mainly by nonspecific electrostatic interactions between their N termini and the negatively charged lipids such as the phosphatidylinositol polyphosphates PI4P and PI(4,5)P2, which are embedded in the inner leaflet of the plasma membrane. Moreover, oligomerization of the long or short form by interaction of their respective upstream conserved region domains, UCR1 and UCR2, enhanced their plasma membrane targeting. These results suggest that the long and short forms of ApPDE4 are distinctly targeted to intracellular membranes through their direct association with the membranes via hydrophobic and electrostatic interactions, respectively.
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Affiliation(s)
- Kun-Hyung Kim
- From the Department of Ecological Science, College of Ecology and Environment, Kyungpook National University, 386, Gajang-dong, Sangju-si, Kyungbuk 742-711, Korea
| | - Yong-Woo Jun
- From the Department of Ecological Science, College of Ecology and Environment, Kyungpook National University, 386, Gajang-dong, Sangju-si, Kyungbuk 742-711, Korea
| | - Yongsoo Park
- the Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Jin-A Lee
- the Department of Biotechnology, College of Life Science and Nanotechnology, Hannam University, 461-6, Jeonmin-dong, Yuseong-gu, Daejeon 305-811, Korea
| | - Byung-Chang Suh
- the Department of Brain Science, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 711-873, Korea
| | - Chae-Seok Lim
- the Department of Biological Sciences, College of Natural Sciences, Seoul National University, 599 Gwanangno, Gwanak-gu, Seoul 151-747, Korea, and
| | - Yong-Seok Lee
- the Department of Life Science, College of Natural Science, Chung-Ang University, Seoul 156-756, Korea
| | - Bong-Kiun Kaang
- the Department of Biological Sciences, College of Natural Sciences, Seoul National University, 599 Gwanangno, Gwanak-gu, Seoul 151-747, Korea, and
| | - Deok-Jin Jang
- From the Department of Ecological Science, College of Ecology and Environment, Kyungpook National University, 386, Gajang-dong, Sangju-si, Kyungbuk 742-711, Korea,
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The upstream conserved regions (UCRs) mediate homo- and hetero-oligomerization of type 4 cyclic nucleotide phosphodiesterases (PDE4s). Biochem J 2014; 459:539-50. [PMID: 24555506 DOI: 10.1042/bj20131681] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PDE4s (type 4 cyclic nucleotide phosphodiesterases) are divided into long and short forms by the presence or absence of conserved N-terminal domains termed UCRs (upstream conserved regions). We have shown previously that PDE4D2, a short variant, is a monomer, whereas PDE4D3, a long variant, is a dimer. In the present study, we have determined the apparent molecular masses of various long and short PDE4 variants by size-exclusion chromatography and sucrose density-gradient centrifugation. Our results indicate that dimerization is a conserved property of all long PDE4 forms, whereas short forms are monomers. Dimerization is mediated by the UCR domains. Given their high sequence conservation, the UCR domains mediate not only homo-oligomerization, but also hetero-oligomerization of distinct PDE4 long forms as detected by co-immunoprecipitation assays and FRET microscopy. Endogenous PDE4 hetero-oligomers are, however, low in abundance compared with homo-dimers, revealing the presence of mechanisms that predispose PDE4s towards homo-oligomerization. Oligomerization is a prerequisite for the regulatory properties of the PDE4 long forms, such as their PKA (protein kinase A)-dependent activation, but is not necessary for PDE4 protein-protein interactions. As a result, individual PDE4 protomers may independently mediate protein-protein interactions, providing a mechanism whereby PDE4s contribute to the assembly of macromolecular signalling complexes.
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Azevedo MF, Faucz FR, Bimpaki E, Horvath A, Levy I, de Alexandre RB, Ahmad F, Manganiello V, Stratakis CA. Clinical and molecular genetics of the phosphodiesterases (PDEs). Endocr Rev 2014; 35:195-233. [PMID: 24311737 PMCID: PMC3963262 DOI: 10.1210/er.2013-1053] [Citation(s) in RCA: 196] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 11/06/2013] [Indexed: 12/31/2022]
Abstract
Cyclic nucleotide phosphodiesterases (PDEs) are enzymes that have the unique function of terminating cyclic nucleotide signaling by catalyzing the hydrolysis of cAMP and GMP. They are critical regulators of the intracellular concentrations of cAMP and cGMP as well as of their signaling pathways and downstream biological effects. PDEs have been exploited pharmacologically for more than half a century, and some of the most successful drugs worldwide today affect PDE function. Recently, mutations in PDE genes have been identified as causative of certain human genetic diseases; even more recently, functional variants of PDE genes have been suggested to play a potential role in predisposition to tumors and/or cancer, especially in cAMP-sensitive tissues. Mouse models have been developed that point to wide developmental effects of PDEs from heart function to reproduction, to tumors, and beyond. This review brings together knowledge from a variety of disciplines (biochemistry and pharmacology, oncology, endocrinology, and reproductive sciences) with emphasis on recent research on PDEs, how PDEs affect cAMP and cGMP signaling in health and disease, and what pharmacological exploitations of PDEs may be useful in modulating cyclic nucleotide signaling in a way that prevents or treats certain human diseases.
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Affiliation(s)
- Monalisa F Azevedo
- Section on Endocrinology Genetics (M.F.A., F.R.F., E.B., A.H., I.L., R.B.d.A., C.A.S.), Program on Developmental Endocrinology Genetics, Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland 20892; Section of Endocrinology (M.F.A.), University Hospital of Brasilia, Faculty of Medicine, University of Brasilia, Brasilia 70840-901, Brazil; Group for Advanced Molecular Investigation (F.R.F., R.B.d.A.), Graduate Program in Health Science, Medical School, Pontificia Universidade Catolica do Paraná, Curitiba 80215-901, Brazil; Cardiovascular Pulmonary Branch (F.A., V.M.), National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland 20892; and Pediatric Endocrinology Inter-Institute Training Program (C.A.S.), NICHD, NIH, Bethesda, Maryland 20892
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Mika D, Richter W, Westenbroek RE, Catterall WA, Conti M. PDE4B mediates local feedback regulation of β₁-adrenergic cAMP signaling in a sarcolemmal compartment of cardiac myocytes. J Cell Sci 2014; 127:1033-42. [PMID: 24413164 DOI: 10.1242/jcs.140251] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Multiple cAMP phosphodiesterase (PDE) isoforms play divergent roles in cardiac homeostasis but the molecular basis for their non-redundant function remains poorly understood. Here, we report a novel role for the PDE4B isoform in β-adrenergic (βAR) signaling in the heart. Genetic ablation of PDE4B disrupted βAR-induced cAMP transients, as measured by FRET sensors, at the sarcolemma but not in the bulk cytosol of cardiomyocytes. This effect was further restricted to a subsarcolemmal compartment because PDE4B regulates β1AR-, but not β2AR- or PGE2-induced responses. The spatially restricted function of PDE4B was confirmed by its selective effects on PKA-mediated phosphorylation patterns. PDE4B limited the PKA-mediated phosphorylation of key players in excitation-contraction coupling that reside in the sarcolemmal compartment, including L-type Ca(2+) channels and ryanodine receptors, but not phosphorylation of distal cytosolic proteins. β1AR- but not β2AR-ligation induced PKA-dependent activation of PDE4B and interruption of this negative feedback with PKA inhibitors increased sarcolemmal cAMP. Thus, PDE4B mediates a crucial PKA-dependent feedback that controls β1AR-dependent cAMP signals in a restricted subsarcolemmal domain. Disruption of this feedback augments local cAMP/PKA signals, leading to an increased intracellular Ca(2+) level and contraction rate.
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Affiliation(s)
- Delphine Mika
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of California San Francisco, San Francisco, CA 94143, USA
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40
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Blanchard E, Zlock L, Lao A, Mika D, Namkung W, Xie M, Scheitrum C, Gruenert DC, Verkman AS, Finkbeiner WE, Conti M, Richter W. Anchored PDE4 regulates chloride conductance in wild-type and ΔF508-CFTR human airway epithelia. FASEB J 2013; 28:791-801. [PMID: 24200884 DOI: 10.1096/fj.13-240861] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Cystic fibrosis (CF) is caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) that impair its expression and/or chloride channel function. Here, we provide evidence that type 4 cyclic nucleotide phosphodiesterases (PDE4s) are critical regulators of the cAMP/PKA-dependent activation of CFTR in primary human bronchial epithelial cells. In non-CF cells, PDE4 inhibition increased CFTR activity under basal conditions (ΔISC 7.1 μA/cm(2)) and after isoproterenol stimulation (increased ΔISC from 13.9 to 21.0 μA/cm(2)) and slowed the return of stimulated CFTR activity to basal levels by >3-fold. In cells homozygous for ΔF508-CFTR, the most common mutation found in CF, PDE4 inhibition alone produced minimal channel activation. However, PDE4 inhibition strongly amplified the effects of CFTR correctors, drugs that increase expression and membrane localization of CFTR, and/or CFTR potentiators, drugs that increase channel gating, to reach ∼ 25% of the chloride conductance observed in non-CF cells. Biochemical studies indicate that PDE4s are anchored to CFTR and mediate a local regulation of channel function. Taken together, our results implicate PDE4 as an important determinant of CFTR activity in airway epithelia, and support the use of PDE4 inhibitors to potentiate the therapeutic benefits of CFTR correctors and potentiators.
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Affiliation(s)
- Elise Blanchard
- 1Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California San Francisco, 513 Parnassus Ave., Box 0556, San Francisco, CA 94143-0556, USA.
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Richter W, Menniti FS, Zhang HT, Conti M. PDE4 as a target for cognition enhancement. Expert Opin Ther Targets 2013; 17:1011-27. [PMID: 23883342 DOI: 10.1517/14728222.2013.818656] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
INTRODUCTION The second messengers cAMP and cGMP mediate fundamental aspects of brain function relevant to memory, learning, and cognitive functions. Consequently, cyclic nucleotide phosphodiesterases (PDEs), the enzymes that inactivate the cyclic nucleotides, are promising targets for the development of cognition-enhancing drugs. AREAS COVERED PDE4 is the largest of the 11 mammalian PDE families. This review covers the properties and functions of the PDE4 family, highlighting procognitive and memory-enhancing effects associated with their inactivation. EXPERT OPINION PAN-selective PDE4 inhibitors exert a number of memory- and cognition-enhancing effects and have neuroprotective and neuroregenerative properties in preclinical models. The major hurdle for their clinical application is to target inhibitors to specific PDE4 isoforms relevant to particular cognitive disorders to realize the therapeutic potential while avoiding side effects, in particular emesis and nausea. The PDE4 family comprises four genes, PDE4A-D, each expressed as multiple variants. Progress to date stems from characterization of rodent models with selective ablation of individual PDE4 subtypes, revealing that individual subtypes exert unique and non-redundant functions in the brain. Thus, targeting specific PDE4 subtypes, as well as splicing variants or conformational states, represents a promising strategy to separate the therapeutic benefits from the side effects of PAN-PDE4 inhibitors.
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Affiliation(s)
- Wito Richter
- University of California San Francisco, Department of Obstetrics, Gynecology and Reproductive Sciences, San Francisco, CA 94143-0556, USA.
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Richter W, Mika D, Blanchard E, Day P, Conti M. β1-adrenergic receptor antagonists signal via PDE4 translocation. EMBO Rep 2013; 14:276-83. [PMID: 23381222 DOI: 10.1038/embor.2013.4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Revised: 12/27/2012] [Accepted: 01/15/2013] [Indexed: 02/06/2023] Open
Abstract
It is generally assumed that antagonists of Gs-coupled receptors do not activate cAMP signalling, because they do not stimulate cAMP production via Gs-protein/adenylyl cyclase activation. Here, we report a new signalling pathway whereby antagonists of β1-adrenergic receptors (β1ARs) increase cAMP levels locally without stimulating cAMP production directly. Binding of antagonists causes dissociation of a preformed complex between β1ARs and Type-4 cyclic nucleotide phosphodiesterases (PDE4s). This reduces the local concentration of cAMP-hydrolytic activity, thereby increasing submembrane cAMP and PKA activity. Our study identifies receptor/PDE4 complex dissociation as a novel mechanism of antagonist action that contributes to the pharmacological properties of β1AR antagonists and might be shared by other receptor subtypes.
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Affiliation(s)
- Wito Richter
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of California San Francisco, San Francisco, California 94143, USA
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43
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Lee H, DeLoache WC, Dueber JE. Spatial organization of enzymes for metabolic engineering. Metab Eng 2012; 14:242-51. [DOI: 10.1016/j.ymben.2011.09.003] [Citation(s) in RCA: 155] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Revised: 07/27/2011] [Accepted: 09/09/2011] [Indexed: 10/17/2022]
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Banjac A, Kurz U, Schultz JE. The regulatory tandem domains of human phosphodiesterases 1 and 4 regulate a cyanobacterial adenylyl cyclase. Cell Signal 2012; 24:1479-84. [PMID: 22484154 DOI: 10.1016/j.cellsig.2012.03.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 03/08/2012] [Accepted: 03/22/2012] [Indexed: 10/28/2022]
Abstract
Human phosphodiesterase 1 is regulated by a tandem of N-terminal calmodulin/Ca(2+)-binding domains. We grafted the tandems from hPDE1A3 and -B1 onto the cyanobacterial adenylyl cyclase CyaB1 thus replacing an intrinsic tandem GAF-domain. Cyclase activity was stimulated by Ca(2+)/calmodulin 1.9 to 4.4-fold, i.e. similarly as reported for hPDE1 regulation. hPDE4 long isoforms are activated by phosphorylation of a serine located in a conserved RRESF motif in a tandem of N-terminal upstream-conserved regions (UCR). We grafted the UCR tandems from hPDE4A4, -B1, and -D3 onto the CyaB1 cyclase as a reporter enzyme. Activity was enhanced 1.4 to 4.5-fold by respective phosphomimetic (S/D) point mutations. Similarly, cyclase activity was increased 2.5-fold by phosphorylation of the chimera with the PDE4D3 UCR tandem by cAMP-dependent protein kinase. We propose a common mechanism of activation in mammalian phosphodiesterases containing N-terminal tandem regulatory domains. A downstream region is suggested to alternate between random and ordered conformations and to enable switching between inactive, the catalytic domain occluding PDE homodimers and active monomeric PDE catalytic domains.
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Affiliation(s)
- Ana Banjac
- Pharmazeutisches Institut, Universität Tübingen, Tübingen, Germany
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Leroy J, Richter W, Mika D, Castro LRV, Abi-Gerges A, Xie M, Scheitrum C, Lefebvre F, Schittl J, Mateo P, Westenbroek R, Catterall WA, Charpentier F, Conti M, Fischmeister R, Vandecasteele G. Phosphodiesterase 4B in the cardiac L-type Ca²⁺ channel complex regulates Ca²⁺ current and protects against ventricular arrhythmias in mice. J Clin Invest 2011; 121:2651-61. [PMID: 21670503 DOI: 10.1172/jci44747] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2010] [Accepted: 04/20/2011] [Indexed: 11/17/2022] Open
Abstract
β-Adrenergic receptors (β-ARs) enhance cardiac contractility by increasing cAMP levels and activating PKA. PKA increases Ca²⁺-induced Ca²⁺ release via phosphorylation of L-type Ca²⁺ channels (LTCCs) and ryanodine receptor 2. Multiple cyclic nucleotide phosphodiesterases (PDEs) regulate local cAMP concentration in cardiomyocytes, with PDE4 being predominant for the control of β-AR-dependent cAMP signals. Three genes encoding PDE4 are expressed in mouse heart: Pde4a, Pde4b, and Pde4d. Here we show that both PDE4B and PDE4D are tethered to the LTCC in the mouse heart but that β-AR stimulation of the L-type Ca²⁺ current (ICa,L) is increased only in Pde4b-/- mice. A fraction of PDE4B colocalized with the LTCC along T-tubules in the mouse heart. Under β-AR stimulation, Ca²⁺ transients, cell contraction, and spontaneous Ca²⁺ release events were increased in Pde4b-/- and Pde4d-/- myocytes compared with those in WT myocytes. In vivo, after intraperitoneal injection of isoprenaline, catheter-mediated burst pacing triggered ventricular tachycardia in Pde4b-/- mice but not in WT mice. These results identify PDE4B in the CaV1.2 complex as a critical regulator of ICa,L during β-AR stimulation and suggest that distinct PDE4 subtypes are important for normal regulation of Ca²⁺-induced Ca²⁺ release in cardiomyocytes.
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Xie M, Rich TC, Scheitrum C, Conti M, Richter W. Inactivation of multidrug resistance proteins disrupts both cellular extrusion and intracellular degradation of cAMP. Mol Pharmacol 2011; 80:281-93. [PMID: 21551375 DOI: 10.1124/mol.111.071134] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
In addition to xenobiotics and several other endogenous metabolites, multidrug-resistance proteins (MRPs) extrude the second-messenger cAMP from various cells. Pharmacological and/or genetic inactivation of MRPs has been shown to augment intracellular cAMP signaling, an effect assumed to be a direct consequence of the blockade of cAMP extrusion. Here we provide evidence that the augmented intracellular cAMP levels are not due exclusively to the prevention of cAMP efflux because MRP inactivation is also associated with reduced cAMP degradation by phosphodiesterases (PDEs). Several prototypical MRP inhibitors block PDE activity at concentrations widely used to inhibit MRPs. Their dose-dependent effects in several paradigms of cAMP signaling are more consistent with their potency in inhibiting PDEs than MRPs. Moreover, genetic manipulation of MRP expression results in concomitant changes in PDE activity and protein levels, thus affecting cAMP degradation in parallel with cAMP efflux. These findings suggest that the effects of MRP inactivation on intracellular cAMP levels reported previously may be due in part to reduced degradation by PDEs and identify MRP-dependent transport mechanisms as novel regulators of cellular PDE expression levels. Mathematical simulations of cAMP signaling predict that selective ablation of MRP-dependent cAMP efflux per se does not affect bulk cytosolic cAMP levels, but may control cAMP levels in restricted submembrane compartments that are defined by small volume, high MRP activity, limited PDE activity, and limited exchange of cAMP with the bulk-cytosolic cAMP pool. Whether this regulation occurs in cells remains to be confirmed experimentally under conditions that do not affect PDE activity.
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Affiliation(s)
- Moses Xie
- Department of Gynecology, Obstetrics and Reproductive Sciences, University of California San Francisco, 513 Parnassus Ave., Box 0556, San Francisco, CA 94143-0556, USA
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Francis SH, Blount MA, Corbin JD. Mammalian Cyclic Nucleotide Phosphodiesterases: Molecular Mechanisms and Physiological Functions. Physiol Rev 2011; 91:651-90. [DOI: 10.1152/physrev.00030.2010] [Citation(s) in RCA: 451] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The superfamily of cyclic nucleotide (cN) phosphodiesterases (PDEs) is comprised of 11 families of enzymes. PDEs break down cAMP and/or cGMP and are major determinants of cellular cN levels and, consequently, the actions of cN-signaling pathways. PDEs exhibit a range of catalytic efficiencies for breakdown of cAMP and/or cGMP and are regulated by myriad processes including phosphorylation, cN binding to allosteric GAF domains, changes in expression levels, interaction with regulatory or anchoring proteins, and reversible translocation among subcellular compartments. Selective PDE inhibitors are currently in clinical use for treatment of erectile dysfunction, pulmonary hypertension, intermittent claudication, and chronic pulmonary obstructive disease; many new inhibitors are being developed for treatment of these and other maladies. Recently reported x-ray crystallographic structures have defined features that provide for specificity for cAMP or cGMP in PDE catalytic sites or their GAF domains, as well as mechanisms involved in catalysis, oligomerization, autoinhibition, and interactions with inhibitors. In addition, major advances have been made in understanding the physiological impact and the biochemical basis for selective localization and/or recruitment of specific PDE isoenzymes to particular subcellular compartments. The many recent advances in understanding PDE structures, functions, and physiological actions are discussed in this review.
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Affiliation(s)
- Sharron H. Francis
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee; and Department of Medicine-Renal Division, Emory University School of Medicine, Atlanta, Georgia
| | - Mitsi A. Blount
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee; and Department of Medicine-Renal Division, Emory University School of Medicine, Atlanta, Georgia
| | - Jackie D. Corbin
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee; and Department of Medicine-Renal Division, Emory University School of Medicine, Atlanta, Georgia
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Blackman BE, Horner K, Heidmann J, Wang D, Richter W, Rich TC, Conti M. PDE4D and PDE4B function in distinct subcellular compartments in mouse embryonic fibroblasts. J Biol Chem 2011; 286:12590-601. [PMID: 21288894 PMCID: PMC3069460 DOI: 10.1074/jbc.m110.203604] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Signaling through cAMP regulates most cellular functions. The spatiotemporal control of cAMP is, therefore, crucial for differential regulation of specific cellular targets. Here we investigated the consequences of PDE4B or PDE4D gene ablation on cAMP signaling at a subcellular level using mouse embryonic fibroblasts. PDE4B ablation had no effect on the global or bulk cytosol accumulation of cAMP but increased both basal and hormone-dependent cAMP in a near-membrane pool. Conversely, PDE4D ablation enhanced agonist-induced cAMP accumulation in the bulk cytosol as well as at the plasma membrane. Both PDE4B and PDE4D ablation significantly modified the time course and the level of isoproterenol-induced phosphorylation of vasodilator-stimulated phosphoprotein, a membrane cytoskeletal component. A second membrane response through Toll-like receptor signaling, however, was only affected by PDE4B ablation. PDE4D but not PDE4B ablation significantly prolonged cAMP-response element-binding protein-mediated transcription. These findings demonstrate that PDE4D and PDE4B have specialized functions in mouse embryonic fibroblasts with PDE4B controlling cAMP in a discrete subdomain near the plasma membrane.
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Affiliation(s)
- Brigitte E Blackman
- Center for Reproductive Sciences, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California San Francisco School of Medicine, San Francisco, California 94143, USA
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Abstract
Cyclic nucleotide phosphodiesterases (PDEs) are promising targets for pharmacological intervention. The presence of multiple PDE genes, diversity of the isoforms produced from each gene, selective tissue and cellular expression of the isoforms, compartmentation within cells, and an array of conformations of PDE proteins are some of the properties that challenge the development of drugs that target these enzymes. Nevertheless, many of the characteristics of PDEs are also viewed as unique opportunities to increase specificity and selectivity when designing novel compounds for certain therapeutic indications. This chapter provides a summary of the major concepts related to the design and use of PDE inhibitors. The overall structure and properties of the catalytic domain and conformations of PDEs are summarized in light of the most recent X-ray crystal structures. The distinctive properties of catalytic domains of different families as well as the technical challenges associated with probing PDE properties and their interactions with small molecules are discussed. The effect of posttranslational modifications and protein-protein interactions are additional factors to be considered when designing PDE inhibitors. PDE inhibitor interaction with other proteins needs to be taken into account and is also discussed.
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Gurney ME, Burgin AB, Magnusson OT, Stewart LJ. Small molecule allosteric modulators of phosphodiesterase 4. Handb Exp Pharmacol 2011:167-92. [PMID: 21695640 DOI: 10.1007/978-3-642-17969-3_7] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Phosphodiesterase 4 (PDE4) inhibitors have shown benefit in human clinical trials but dosing is limited by tolerability, particularly because of emesis. Novel cocrystal structures of PDE4 catalytic units with their regulatory domains together with bound inhibitors have revealed three different PDE4 conformers that can be exploited in the design of novel therapeutic agents. The first is an open conformer, which has been employed in the traditional approach to the design of competitive PDE4 inhibitors. The second is an asymmetric dimer in which a UCR2 regulatory helix from one monomer is placed in a closed conformation over the opposite active site in the PDE4 dimer (trans-capping). Only one active site can be closed by an inhibitor at a time with the consequence that compounds exploiting this conformer only partially inhibit PDE4 enzymatic activity while retaining potency in cellular and in vivo models. By placing an intrinsic ceiling on the magnitude of PDE4 inhibition, such compounds may better maintain spatial and temporal patterning of signaling in cAMP microdomains with consequent improved tolerability. The third is a symmetric PDE4 conformer in which helices from the C-terminal portion of the catalytic unit cap both active sites (cis-capping). We propose that dual-gating of PDE4 activity may be further fine tuned by accessory proteins that recognize open or closed conformers of PDE4 regulatory helices.
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