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Kolb M, Crestani B, Maher TM. Phosphodiesterase 4B inhibition: a potential novel strategy for treating pulmonary fibrosis. Eur Respir Rev 2023; 32:32/167/220206. [PMID: 36813290 PMCID: PMC9949383 DOI: 10.1183/16000617.0206-2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 12/04/2022] [Indexed: 02/24/2023] Open
Abstract
Patients with interstitial lung disease can develop a progressive fibrosing phenotype characterised by an irreversible, progressive decline in lung function despite treatment. Current therapies slow, but do not reverse or stop, disease progression and are associated with side-effects that can cause treatment delay or discontinuation. Most crucially, mortality remains high. There is an unmet need for more efficacious and better-tolerated and -targeted treatments for pulmonary fibrosis. Pan-phosphodiesterase 4 (PDE4) inhibitors have been investigated in respiratory conditions. However, the use of oral inhibitors can be complicated due to class-related systemic adverse events, including diarrhoea and headaches. The PDE4B subtype, which has an important role in inflammation and fibrosis, has been identified in the lungs. Preferentially targeting PDE4B has the potential to drive anti-inflammatory and antifibrotic effects via a subsequent increase in cAMP, but with improved tolerability. Phase I and II trials of a novel PDE4B inhibitor in patients with idiopathic pulmonary fibrosis have shown promising results, stabilising pulmonary function measured by change in forced vital capacity from baseline, while maintaining an acceptable safety profile. Further research into the efficacy and safety of PDE4B inhibitors in larger patient populations and for a longer treatment period is needed.
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Affiliation(s)
- Martin Kolb
- Department of Respiratory Medicine, Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada,Firestone Institute for Respiratory Health, St Joseph's Healthcare, Hamilton, ON, Canada
| | - Bruno Crestani
- Service de Pneumologie A, Hôpital Bichat, APHP, Paris, France,INSERM, Unité 1152, Université Paris Cité, Paris, France
| | - Toby M. Maher
- Keck Medicine of USC, Los Angeles, CA, USA,National Heart and Lung Institute, Imperial College London, London, UK,Corresponding author: Toby M. Maher ()
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Kong G, Lee H, Vo TTT, Juang U, Kwon SH, Park J, Park J, Kim SH. Functional characteristics and research trends of PDE11A in human diseases (Review). Mol Med Rep 2022; 26:298. [PMID: 35929507 PMCID: PMC9434997 DOI: 10.3892/mmr.2022.12814] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 06/15/2022] [Indexed: 11/06/2022] Open
Abstract
cAMP and cGMP are important secondary messengers involved in cell regulation and metabolism driven by the G protein-coupled receptor. cAMP is converted via adenylyl cyclase (AC) and activates protein kinase A to phosphorylate intracellular proteins that mediate specific responses. cAMP signaling serves a role at multiple steps in tumorigenesis. The level of cAMP is increased in association with cancer cell formation through activation of AC-stimulatory G protein by mutation. Phosphodiesterases (PDEs) hydrolyze cAMP and cGMP to AMP and GMP. PDEs are composed of 11 families, and each can hydrolyze cAMP and cGMP or both cAMP and cGMP. PDEs perform various roles depending on their location and expression site, and are involved in several diseases, including male erectile dysfunction, pulmonary hypertension, Alzheimer's disease and schizophrenia. PDE11A is the 11th member of the PDE family and is characterized by four splice variants with varying tissue expression and N-terminal regulatory regions. Among tissues, the expression of PDE11A was highest in the prostate, and it was also expressed in hepatic skeletal muscle, pituitary, pancreas and kidney. PDE11A is the first PDE associated with an adrenocortical tumor associated genetic condition. In several studies, three PDE11A mutations have been reported in patients with Cushing syndrome with primary pigmented nodular adrenocortical disease or isolated micronodular adrenocortical disease without other genetic defects. It has been reported that an increase in PDE11A expression affects the proliferation of glioblastoma and worsens patient prognosis. The present mini-review summarizes the location of PDE11A expression, the impact of structural differences and disease relevance.
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Affiliation(s)
- Gyeyeong Kong
- Department of Pharmacology, Metabolic Syndrome and Cell Signaling Laboratory, Institute for Cancer Research, College of Medicine, Chungnam National University, Daejeon 35015, Republic of Korea
| | - Hyunji Lee
- Department of Pharmacology, Metabolic Syndrome and Cell Signaling Laboratory, Institute for Cancer Research, College of Medicine, Chungnam National University, Daejeon 35015, Republic of Korea
| | - Thuy-Trang T Vo
- Department of Pharmacology, Metabolic Syndrome and Cell Signaling Laboratory, Institute for Cancer Research, College of Medicine, Chungnam National University, Daejeon 35015, Republic of Korea
| | - Uijin Juang
- Department of Pharmacology, Metabolic Syndrome and Cell Signaling Laboratory, Institute for Cancer Research, College of Medicine, Chungnam National University, Daejeon 35015, Republic of Korea
| | - So Hee Kwon
- College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon 21983, Republic of Korea
| | - Jisoo Park
- Mitos Research Institute, Mitos Therapeutics Inc., Daejeon 34134, Republic of Korea
| | - Jongsun Park
- Department of Pharmacology, Metabolic Syndrome and Cell Signaling Laboratory, Institute for Cancer Research, College of Medicine, Chungnam National University, Daejeon 35015, Republic of Korea
| | - Seon-Hwan Kim
- Department of Neurosurgery, Institute for Cancer Research, College of Medicine, Chungnam National University, Daejeon 35015, Republic of Korea
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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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Bhat A, Ray B, Mahalakshmi AM, Tuladhar S, Nandakumar DN, Srinivasan M, Essa MM, Chidambaram SB, Guillemin GJ, Sakharkar MK. Phosphodiesterase-4 enzyme as a therapeutic target in neurological disorders. Pharmacol Res 2020; 160:105078. [PMID: 32673703 DOI: 10.1016/j.phrs.2020.105078] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 07/09/2020] [Accepted: 07/10/2020] [Indexed: 02/08/2023]
Abstract
Phosphodiesterases (PDE) are a diverse family of enzymes (11 isoforms so far identified) responsible for the degradation of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) which are involved in several cellular and biochemical functions. Phosphodiesterase 4 (PDE4) is the major isoform within this group and is highly expressed in the mammalian brain. An inverse association between PDE4 and cAMP levels is the key mechanism in various pathophysiological conditions like airway inflammatory diseases-chronic obstruction pulmonary disease (COPD), asthma, psoriasis, rheumatoid arthritis, and neurological disorders etc. In 2011, roflumilast, a PDE4 inhibitor (PDE4I) was approved for the treatment of COPD. Subsequently, other PDE4 inhibitors (PDE4Is) like apremilast and crisaborole were approved by the Food and Drug Administration (FDA) for psoriasis, atopic dermatitis etc. Due to the adverse effects like unbearable nausea and vomiting, dose intolerance and diarrhoea, PDE4 inhibitors have very less clinical compliance. Efforts are being made to develop allosteric modulation with high specificity to PDE4 isoforms having better efficacy and lesser adverse effects. Interestingly, repositioning PDE4Is towards neurological disorders including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), multiple sclerosis (MS) and sleep disorders, is gaining attention. This review is an attempt to summarize the data on the effects of PDE4 overexpression in neurological disorders and the use of PDE4Is and newer allosteric modulators as therapeutic options. We have also compiled a list of on-going clinical trials on PDE4 inhibitors in neurological disorders.
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Affiliation(s)
- Abid Bhat
- Dept. of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru, India
| | - Bipul Ray
- Dept. of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru, India
| | | | - Sunanda Tuladhar
- Dept. of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru, India
| | - D N Nandakumar
- Department of Neurochemistry, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, 560029, India
| | - Malathi Srinivasan
- Department of Lipid Science, CSIR - Central Food Technological Research Institute (CFTRI), CFTRI Campus, Mysuru, 570020, India
| | - Musthafa Mohamed Essa
- Ageing and Dementia Research Group, Sultan Qaboos University, Muscat, Oman; Department of Food Science and Nutrition, CAMS, Sultan Qaboos University, Muscat, Oman.
| | - Saravana Babu Chidambaram
- Dept. of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru, India; Centre for Experimental Pharmacology and Toxicology, Central Animal Facility, JSS Academy of Higher Education & Research, Mysuru, India.
| | - Gilles J Guillemin
- Neuroinflammation group, Faculty of Medicine and Health Sciences, Macquarie University, NSW, 2109, Australia.
| | - Meena Kishore Sakharkar
- College of Pharmacy and Nutrition, University of Saskatchewan, 107, Wiggins Road, Saskatoon, SK, S7N 5C9, Canada
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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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Bizzi MF, Bolger GB, Korbonits M, Ribeiro-Oliveira Jr. A. Phosphodiesterases and cAMP Pathway in Pituitary Diseases. Front Endocrinol (Lausanne) 2019; 10:141. [PMID: 30941100 PMCID: PMC6433792 DOI: 10.3389/fendo.2019.00141] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 02/15/2019] [Indexed: 12/21/2022] Open
Abstract
Human phosphodiesterases (PDEs) comprise a complex superfamily of enzymes derived from 24 genes separated into 11 PDE gene families (PDEs 1-11), expressed in different tissues and cells, including heart and brain. The isoforms PDE4, PDE7, and PDE8 are specific for the second messenger cAMP, which is responsible for mediating diverse physiological actions involving different hormones and neurotransmitters. The cAMP pathway plays an important role in the development and function of endocrine tissues while phosphodiesterases are responsible for ensuring the appropriate intensity of the actions of this pathway by hydrolyzing cAMP to its inactive form 5'-AMP. PDE1, PDE2, PDE4, and PDE11A are highly expressed in the pituitary, and overexpression of some PDE4 isoforms have been demonstrated in different pituitary adenoma subtypes. This observed over-expression in pituitary adenomas, although of unknown etiology, has been considered a compensatory response to tumorigenesis. PDE4A4/5 has a unique interaction with the co-chaperone aryl hydrocarbon receptor-interacting protein (AIP), a protein implicated in somatotroph tumorigenesis via germline loss-of-function mutations. Based on the association of low PDE4A4 expression with germline AIP-mutation-positive samples, the available data suggest that lack of AIP hinders the upregulation of PDE4A4 protein seen in sporadic somatotrophinomas. This unique disturbance of the cAMP-PDE pathway observed in the majority of AIP-mutation positive adenomas could contribute to their well-described poor response to somatostatin analogs and may support a role in tumorigenesis.
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Affiliation(s)
- Mariana Ferreira Bizzi
- Department of Internal Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Graeme B. Bolger
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
- Department of Pharmacology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Márta Korbonits
- Center for Endocrinology, Barts and The London School of Medicine, William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - Antonio Ribeiro-Oliveira Jr.
- Department of Internal Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil
- *Correspondence: Antonio Ribeiro-Oliveira Jr.
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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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Hansen RT, Conti M, Zhang HT. Mice deficient in phosphodiesterase-4A display anxiogenic-like behavior. Psychopharmacology (Berl) 2014; 231:2941-54. [PMID: 24563185 DOI: 10.1007/s00213-014-3480-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Accepted: 01/24/2014] [Indexed: 12/26/2022]
Abstract
RATIONALE Phosphodiesterases (PDEs) are a super family of enzymes responsible for the halting of intracellular cyclic nucleotide signaling and may represent novel therapeutic targets for treatment of cognitive disorders. PDE4 is of considerable interest to cognitive research because it is highly expressed in the brain, particularly in the cognition-related brain regions. Recently, the functional role of PDE4B and PDE4D, two of the four PDE4 subtypes (PDE4A, B, C, and D), in behavior has begun to be identified; however, the role of PDE4A in the regulation of behavior is still unknown. OBJECTIVES The purpose of this study was to characterize the functional role of PDE4A in behavior. METHODS The role of PDE4A in behavior was evaluated through a battery of behavioral tests using PDE4A knockout (KO) mice; urine corticosterone levels were also measured. RESULTS PDE4A KO mice exhibited improved memory in the step-through-passive-avoidance test. They also displayed anxiogenic-like behavior in elevated-plus maze, holeboard, light-dark transition, and novelty suppressed feeding tests. Consistent with the anxiety profile, PDE4A KO mice had elevated corticosterone levels compared with wild-type controls post-stress. Interestingly, PDE4A KO mice displayed no change in object recognition, Morris water maze, forced swim, tail suspension, and duration of anesthesia induced by co-administration of xylazine and ketamine (suggesting that PDE4A KO may not be emetic). CONCLUSIONS These results suggest that PDE4A may be important in the regulation of emotional memory and anxiety-like behavior, but not emesis. PDE4A could possibly represent a novel therapeutic target in the future for anxiety or disorders affecting memory.
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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 Dr, Morgantown, WV, 26506-9137, USA
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Heterozygous mutations in cyclic AMP phosphodiesterase-4D (PDE4D) and protein kinase A (PKA) provide new insights into the molecular pathology of acrodysostosis. Cell Signal 2014; 26:2446-59. [PMID: 25064455 DOI: 10.1016/j.cellsig.2014.07.025] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Revised: 07/16/2014] [Accepted: 07/16/2014] [Indexed: 12/21/2022]
Abstract
Acrodysostosis without hormone resistance is a rare skeletal disorder characterized by brachydactyly, nasal hypoplasia, mental retardation and occasionally developmental delay. Recently, loss-of-function mutations in the gene encoding cAMP-hydrolyzing phosphodiesterase-4D (PDE4D) have been reported to cause this rare condition but the pathomechanism has not been fully elucidated. To understand the pathogenetic mechanism of PDE4D mutations, we conducted 3D modeling studies to predict changes in the binding efficacy of cAMP to the catalytic pocket in PDE4D mutants. Our results indicated diminished enzyme activity in the two mutants we analyzed (Gly673Asp and Ile678Thr; based on PDE4D4 residue numbering). Ectopic expression of PDE4D mutants in HEK293 cells demonstrated this reduction in activity, which was identified by increased cAMP levels. However, the cells from an acrodysostosis patient showed low cAMP accumulation, which resulted in a decrease in the phosphorylated cAMP Response Element-Binding Protein (pCREB)/CREB ratio. The reason for this discrepancy was due to a compensatory increase in expression levels of PDE4A and PDE4B isoforms, which accounted for the paradoxical decrease in cAMP levels in the patient cells expressing mutant isoforms with a lowered PDE4D activity. Skeletal radiographs of 10-week-old knockout (KO) rats showed that the distal part of the forelimb was shorter than in wild-type (WT) rats and that all the metacarpals and phalanges were also shorter in KO, as the name acrodysostosis implies. Like the G-protein α-stimulatory subunit and PRKAR1A, PDE4D critically regulates the cAMP signal transduction pathway and influences bone formation in a way that activity-compromising PDE4D mutations can result in skeletal dysplasia. We propose that specific inhibitory PDE4D mutations can lead to the molecular pathology of acrodysostosis without hormone resistance but that the pathological phenotype may well be dependent on an over-compensatory induction of other PDE4 isoforms that can be expected to be targeted to different signaling complexes and exert distinct effects on compartmentalized cAMP signaling.
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Otero C, Peñaloza JP, Rodas PI, Fernández-Ramires R, Velasquez L, Jung JE. Temporal and spatial regulation of cAMP signaling in disease: role of cyclic nucleotide phosphodiesterases. Fundam Clin Pharmacol 2014; 28:593-607. [PMID: 24750474 DOI: 10.1111/fcp.12080] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 03/28/2014] [Accepted: 04/17/2014] [Indexed: 01/19/2023]
Abstract
Since its discovery, cAMP has been proposed as one of the most versatile second messengers. The remarkable feature of cAMP to tightly control highly diverse physiological processes, including metabolism, homeostasis, secretion, muscle contraction, cell proliferation and migration, immune response, and gene transcription, is reflected by millions of different articles worldwide. Compartmentalization of cAMP in space and time, maintained by mainly phosphodiesterases, contributes to the maintenance of equilibrium inside the cell where one signal can trigger many different events. Novel cAMP sensors seem to carry out certain unexpected signaling properties of cAMP and thereby to permit delicate adaptations of biologic responses. Measuring space and time events with biosensors will increase our current knowledge on the pathophysiology of diseases, such as chronic obstructive pulmonary disease, asthma, cognitive impairment, cancer, and renal and heart failure. Further insights into the cAMP dynamics will help to optimize the pharmacological treatment for these diseases.
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Affiliation(s)
- Carolina Otero
- Center for Integrative Medicine and Innovative Science, Universidad Andres Bello, Santiago, Chile; Centro para el Desarrollo de la Nanociencia y Nanotecnologia, Santiago, Chile
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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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Safavi M, Baeeri M, Abdollahi M. New methods for the discovery and synthesis of PDE7 inhibitors as new drugs for neurological and inflammatory disorders. Expert Opin Drug Discov 2013; 8:733-51. [DOI: 10.1517/17460441.2013.787986] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Levy I, Horvath A, Azevedo M, de Alexandre RB, Stratakis CA. Phosphodiesterase function and endocrine cells: links to human disease and roles in tumor development and treatment. Curr Opin Pharmacol 2011; 11:689-97. [PMID: 22047791 DOI: 10.1016/j.coph.2011.10.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Accepted: 10/04/2011] [Indexed: 12/20/2022]
Abstract
Phosphodiesterases (PDEs) are enzymes that regulate the intracellular levels of cyclic adenosine monophosphate and cyclic guanosine monophosphate, and, consequently, exhibit a central role in multiple cellular functions. The pharmacological exploitation of the ability of PDEs to regulate specific pathways has led to the discovery of drugs with selective action against specific PDE isoforms. Considerable attention has been given to the development of selective PDE inhibitors, especially after the therapeutic success of PDE5 inhibitors in the treatment of erectile dysfunction. Several associations between PDE genes and genetic diseases have been described, and more recently PDE11A and PDE8B have been implicated in predisposition to tumor formation. This review focuses on the possible function of PDEs in a variety of tumors, primarily in endocrine glands, both in tumor predisposition and as potential therapeutic targets.
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Affiliation(s)
- Isaac Levy
- Section of Endocrinology and Genetics, Program on Developmental Endocrinology Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
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Day JP, Lindsay B, Riddell T, Jiang Z, Allcock RW, Abraham A, Sookup S, Christian F, Bogum J, Martin EK, Rae RL, Anthony D, Rosair GM, Houslay DM, Huston E, Baillie GS, Klussmann E, Houslay MD, Adams DR. Elucidation of a Structural Basis for the Inhibitor-Driven, p62 (SQSTM1)-Dependent Intracellular Redistribution of cAMP Phosphodiesterase-4A4 (PDE4A4). J Med Chem 2011; 54:3331-47. [DOI: 10.1021/jm200070e] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Jonathan P. Day
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, U.K
| | - Barbara Lindsay
- Department of Chemistry, School of Engineering and Physical Sciences, Heriot-Watt University, Riccarton Campus, Edinburgh EH14 4AS, U.K
| | - Tracy Riddell
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, U.K
| | - Zhong Jiang
- Department of Chemistry, School of Engineering and Physical Sciences, Heriot-Watt University, Riccarton Campus, Edinburgh EH14 4AS, U.K
| | - Robert W. Allcock
- Department of Chemistry, School of Engineering and Physical Sciences, Heriot-Watt University, Riccarton Campus, Edinburgh EH14 4AS, U.K
| | - Achamma Abraham
- Department of Chemistry, School of Engineering and Physical Sciences, Heriot-Watt University, Riccarton Campus, Edinburgh EH14 4AS, U.K
| | - Sebastian Sookup
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, U.K
| | - Frank Christian
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, U.K
| | - Jana Bogum
- Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin-Buch, Robert-Rössle-Strasse 10, 13125 Berlin, Germany
| | - Elisabeth K. Martin
- Department of Chemistry, School of Engineering and Physical Sciences, Heriot-Watt University, Riccarton Campus, Edinburgh EH14 4AS, U.K
| | - Robert L. Rae
- Department of Chemistry, School of Engineering and Physical Sciences, Heriot-Watt University, Riccarton Campus, Edinburgh EH14 4AS, U.K
| | - Diana Anthony
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, U.K
| | - Georgina M. Rosair
- Department of Chemistry, School of Engineering and Physical Sciences, Heriot-Watt University, Riccarton Campus, Edinburgh EH14 4AS, U.K
| | - Daniel M. Houslay
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, U.K
| | - Elaine Huston
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, U.K
| | - George S. Baillie
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, U.K
| | - Enno Klussmann
- Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin-Buch, Robert-Rössle-Strasse 10, 13125 Berlin, Germany
| | - Miles D. Houslay
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, U.K
| | - David R. Adams
- Department of Chemistry, School of Engineering and Physical Sciences, Heriot-Watt University, Riccarton Campus, Edinburgh EH14 4AS, U.K
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Francis SH, Sekhar KR, Ke H, Corbin JD. Inhibition of cyclic nucleotide phosphodiesterases by methylxanthines and related compounds. Handb Exp Pharmacol 2011:93-133. [PMID: 20859794 DOI: 10.1007/978-3-642-13443-2_4] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Naturally occurring methylxanthines were the first inhibitors of cyclic nucleotide (cN) phosphodiesterases (PDEs) to be discovered. To improve potency and specificity for inhibition of various PDEs in research and for treatment of diseases, thousands of compounds with related structures have now been synthesized. All known PDE inhibitors contain one or more rings that mimic the purine in the cN substrate and directly compete with cN for access to the catalytic site; this review focuses on inhibitors that contain a nucleus that is closely related to the xanthine ring of theophylline and caffeine and the purine ring of cNs. The specificity and potency of these compounds for blocking PDE action have been improved by appending groups at positions on the rings as well as by modification of the number and distribution of nitrogens and carbons in those rings. Several of these inhibitors are highly selective for particular PDEs; potent and largely selective PDE5 inhibitors are used clinically for treatment of erectile dysfunction [sildenafil (Viagra™), tadalafil (Cialis™) and vardenafil (Levitra™)] and pulmonary hypertension [sildenafil (Revatio™) and tadalafil (Adenocirca)]. Related compounds target other PDEs and show therapeutic promise for a number of maladies.
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Affiliation(s)
- Sharron H Francis
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232-0615, USA.
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Conserved expression and functions of PDE4 in rodent and human heart. Basic Res Cardiol 2010; 106:249-62. [PMID: 21161247 PMCID: PMC3032896 DOI: 10.1007/s00395-010-0138-8] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Revised: 11/17/2010] [Accepted: 12/01/2010] [Indexed: 01/21/2023]
Abstract
PDE4 isoenzymes are critical in the control of cAMP signaling in rodent cardiac myocytes. Ablation of PDE4 affects multiple key players in excitation–contraction coupling and predisposes mice to the development of heart failure. As little is known about PDE4 in human heart, we explored to what extent cardiac expression and functions of PDE4 are conserved between rodents and humans. We find considerable similarities including comparable amounts of PDE4 activity expressed, expression of the same PDE4 subtypes and splicing variants, anchoring of PDE4 to the same subcellular compartments and macromolecular signaling complexes, and downregulation of PDE4 activity and protein in heart failure. The major difference between the species is a fivefold higher amount of non-PDE4 activity in human hearts compared to rodents. As a consequence, the effect of PDE4 inactivation is different in rodents and humans. PDE4 inhibition leads to increased phosphorylation of virtually all PKA substrates in mouse cardiomyocytes, but increased phosphorylation of only a restricted number of proteins in human cardiomyocytes. Our findings suggest that PDE4s have a similar role in the local regulation of cAMP signaling in rodent and human heart. However, inhibition of PDE4 has ‘global’ effects on cAMP signaling only in rodent hearts, as PDE4 comprises a large fraction of the total cardiac PDE activity in rodents but not in humans. These differences may explain the distinct pharmacological effects of PDE4 inhibition in rodent and human hearts.
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Johnson KR, Nicodemus-Johnson J, Danziger RS. An evolutionary analysis of cAMP-specific Phosphodiesterase 4 alternative splicing. BMC Evol Biol 2010; 10:247. [PMID: 20701803 PMCID: PMC2929239 DOI: 10.1186/1471-2148-10-247] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Accepted: 08/11/2010] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Cyclic nucleotide phosphodiesterases (PDEs) hydrolyze the intracellular second messengers: cyclic adenosine monophosphate (cAMP) and cyclic guanine monophosphate (cGMP). The cAMP-specific PDE family 4 (PDE4) is widely expressed in vertebrates. Each of the four PDE4 gene isoforms (PDE4 A-D) undergo extensive alternative splicing via alternative transcription initiation sites, producing unique amino termini and yielding multiple splice variant forms from each gene isoform termed long, short, super-short and truncated super-short. Many species across the vertebrate lineage contain multiple splice variants of each gene type, which are characterized by length and amino termini. RESULTS A phylogenetic approach was used to visualize splice variant form genesis and identify conserved splice variants (genome conservation with EST support) across the vertebrate taxa. Bayesian and maximum likelihood phylogenetic inference indicated PDE4 gene duplication occurred at the base of the vertebrate lineage and reveals additional gene duplications specific to the teleost lineage. Phylogenetic inference and PDE4 splice variant presence, or absence as determined by EST screens, were further supported by the genomic analysis of select vertebrate taxa. Two conserved PDE4 long form splice variants were found in each of the PDE4A, PDE4B, and PDE4C genes, and eight conserved long forms from the PDE4 D gene. Conserved short and super-short splice variants were found from each of the PDE4A, PDE4B, and PDE4 D genes, while truncated super-short variants were found from the PDE4C and PDE4 D genes. PDE4 long form splice variants were found in all taxa sampled (invertebrate through mammals); short, super-short, and truncated super-short are detected primarily in tetrapods and mammals, indicating an increasing complexity in both alternative splicing and cAMP metabolism through vertebrate evolution. CONCLUSIONS There was a progressive independent incorporation of multiple PDE4 splice variant forms and amino termini, increasing PDE4 proteome complexity from primitive vertebrates to humans. While PDE4 gene isoform duplicates with limited alternative splicing were found in teleosts, an expansion of both PDE4 splice variant forms, and alternatively spliced amino termini predominantly occurs in mammals. Since amino termini have been linked to intracellular targeting of the PDE4 enzymes, the conservation of amino termini in PDE4 splice variants in evolution highlights the importance of compartmentalization of PDE4-mediated cAMP hydrolysis.
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Affiliation(s)
- Keven R Johnson
- Department of Physiology and Biophysics, University of Illinois at Chicago 835 S. Wolcott Avenue, M/C 901, Chicago, IL 60612-7342, USA
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Christian F, Anthony DF, Vadrevu S, Riddell T, Day JP, McLeod R, Adams DR, Baillie GS, Houslay MD. p62 (SQSTM1) and cyclic AMP phosphodiesterase-4A4 (PDE4A4) locate to a novel, reversible protein aggregate with links to autophagy and proteasome degradation pathways. Cell Signal 2010; 22:1576-96. [PMID: 20600853 DOI: 10.1016/j.cellsig.2010.06.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Accepted: 06/15/2010] [Indexed: 02/07/2023]
Abstract
Chronic challenge of cyclic AMP phosphodiesterase-4A4 (PDE4A4) with certain PDE4 selective inhibitors causes it to reversibly form intracellular aggregates that are not membrane-encapsulated. These aggregates are neither stress granules (SGs) nor processing bodies (PBs) as they contain neither PABP-1 nor Dcp1a, respectively. However, the PDE4 inhibitor rolipram decreases arsenite-induced SGs and increases the amount of PBs, while arsenite challenge ablates rolipram-induced PDE4A4 aggregates. PDE4A4 aggregates are neither autophagic vesicles (autophagosomes) nor aggresomes, although microtubule disruptors ablate PDE4A4 aggregate formation. PDE4A4 constitutively co-immunoprecipitates with p62 protein (sequestosome1, SQSTM1), which locates to both PDE4A4 aggregates and autophagosomes in cells constitutively challenged with rolipram. The mTor inhibitor, rapamycin, activates autophagy, prevents PDE4A4 from forming intracellular aggregates and triggers the loss of bound p62 from PDE4A4. siRNA-mediated knockdown of p62 attenuates PDE4A4 aggregate formation. The p62-binding protein, light chain 3 (LC3), is not found in PDE4A4 aggregates. Blockade of proteasome activity and activation of autophagy with MG132 both increases the level of ubiquitinated proteins found associated with PDE4A4 and inhibits PDE4A4 aggregate formation. Activation of autophagy with either thapsigargin or ionomycin inhibits PDE4A4 aggregate formation. Inhibition of autophagy with either wortmannin or LY294002 activates PDE4A4 aggregate formation. The protein kinase C inhibitors, RO 320432 and GO 6983, and the ERK inhibitors UO 126 and PD 98059 all activated PDE4A4 aggregate formation, whilst roscovitine, thalidomide and the tyrosine kinase inhibitors, genistein and AG17, all inhibited this process. We suggest that the fate of p62-containing protein aggregates need not necessarily be terminal, through delivery to autophagic vesicles and aggresomes. Instead, we propose a novel regulatory mechanism where a sub-population of p62-containing protein aggregates would form in a rapid, reversible manner so as to sequester specific cargo away from their normal, functionally important site(s) within the cell. Thus an appropriate conformational change in the target protein would confer reversible recruitment into a sub-population of p62-containing protein aggregates and so provide a regulatory function by removing these cargo proteins from their functionally important site(s) in a cell.
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Affiliation(s)
- Frank Christian
- Neuroscience and Molecular Pharmacology, Wolfson and Davidson Buildings, Faculty of Biomedical & Life Sciences, University of Glasgow, Glasgow, G12 8QQ, Scotland, United Kingdom
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Abstract
Increased levels of 3'-5'-cyclic adenosine monophosphate (cAMP) stimulate cell proliferation and fluid secretion in polycystic kidney disease. Levels of this molecule are more sensitive to inhibition of phosphodiesterases (PDEs), whose activity far exceeds the rate of cAMP synthesis by adenylyl cyclase. Several PDEs exist, and here we measured the activity and expression of PDE families, their isoforms, and the expression of downstream effectors of cAMP signaling in the kidneys of rodents with polycystic kidney disease. We found a higher overall PDE activity in kidneys from mice as compared with rats, as well as a higher contribution of PDE1, relative to PDE4 and PDE3, to total PDE activity of kidney lysates and lower PDE1, PDE3, and PDE4 activities in the kidneys of cystic as compared with wild-type mice. There were reduced amounts of several PDE1, PDE3, and PDE4 proteins, possibly due to increased protein degradation despite an upregulation of their mRNA. Increased levels of cGMP were found in the kidneys of cystic animals, suggesting in vivo downregulation of PDE1 activity. We found an additive stimulatory effect of cAMP and cGMP on cystogenesis in vitro. Cyclic AMP-dependent protein kinase subunits Ialpha and IIbeta, PKare, the transcription factor CREB-1 mRNA, and CREM, ATF-1, and ICER proteins were upregulated in the kidneys of cystic as compared with wild-type animals. Our study suggests that alterations in cyclic nucleotide catabolism may render cystic epithelium particularly susceptible to factors acting on Gs-coupled receptors. This may account, in part, for increased cyclic nucleotide signaling in polycystic kidney disease and contribute substantially to disease progression.
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Affiliation(s)
- Xiaofang Wang
- Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA
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Liu CY, Fraser SE, Koos DS. Grueneberg ganglion olfactory subsystem employs a cGMP signaling pathway. J Comp Neurol 2009; 516:36-48. [PMID: 19565523 DOI: 10.1002/cne.22096] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The mammalian olfactory sense employs several olfactory subsystems situated at characteristic locations in the nasal cavity to detect and report on different classes of odors. These olfactory subsystems use different neuronal signal transduction pathways, receptor expression repertoires, and axonal projection targets. The Grueneberg ganglion (GG) is a newly appreciated olfactory subsystem with receptor neurons located just inside of the nostrils that project axons to a unique domain of interconnected glomeruli in the caudal olfactory bulb. It is not well understood how the GG relates to other olfactory subsystems in contributing to the olfactory sense. Furthermore, the range of chemoreceptors and the signal transduction cascade utilized by the GG have remained mysterious. To resolve these unknowns, we explored the molecular relationship between the GG and the GC-D neurons, another olfactory subsystem that innervates similarly interconnected glomeruli in the same bulbar region. We found that mouse GG neurons express the cGMP-associated signaling proteins phosphodiesterase 2a, cGMP-dependent kinase II, and cyclic nucleotide gated channel subunit A3 coupled to a chemoreceptor repertoire of cilia-localized particulate guanylyl cyclases (pGC-G and pGC-A). The primary cGMP signaling pathway of the GG is shared with the GC-D neurons, unifying their target glomeruli as a unique center of olfactory cGMP signal transduction. However, the distinct chemoreceptor repertoire in the GG suggests that the GG is an independent olfactory subsystem. This subsystem is well suited to detect a unique set of odors and to mediate behaviors that remained intact in previous olfactory perturbations.
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Affiliation(s)
- Cambrian Y Liu
- Biological Imaging Center, California Institute of Technology, Pasadena, California 91125, USA
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PDE4 associates with different scaffolding proteins: modulating interactions as treatment for certain diseases. Handb Exp Pharmacol 2008:125-66. [PMID: 18491051 DOI: 10.1007/978-3-540-72843-6_6] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
cAMP is an ubiquitous second messenger that is crucial to many cellular processes. The sole means of terminating the cAMP signal is degradation by cAMP phosphodiesterases (PDEs). The PDE4 family is of particular interest because PDE4 inhibitors have therapeutic potential for the treatment of various inflammatory and auto-immune diseases and also have anti-depressant and memory-enhancing effects. The subcellular targeting of PDE4 isoforms is fundamental to the compartmentalization of cAMP signaling pathways and is largely achieved via proteinprotein interactions. Increased knowledge of these protein-protein interactions and their regulatory properties could aid in the design of novel isoform-specific inhibitors with improved efficacy and fewer prohibitive side effects.
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McCahill A, Campbell L, McSorley T, Sood A, Lynch MJ, Li X, Yan C, Baillie GS, Houslay MD. In cardiac myocytes, cAMP elevation triggers the down-regulation of transcripts and promoter activity for cyclic AMP phosphodiesterase-4A10 (PDE4A10). Cell Signal 2008; 20:2071-83. [PMID: 18721873 DOI: 10.1016/j.cellsig.2008.07.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2008] [Accepted: 07/28/2008] [Indexed: 12/11/2022]
Abstract
Transcripts for the PDE4A10 cyclic AMP phosphodiesterase isoform are present in a wide variety of rat tissues including the heart. Sequence comparisons between the putative human and mouse promoters revealed a number of conserved regions including both an Sp1 and a CREB-binding site. The putative mouse PDE4A10 promoter was amplified from genomic DNA and sub-cloned into a luciferase reporter vector for investigation of activity in neonatal cardiac myocytes. Transfection with this construct identified a high level of luciferase expression in neonatal cardiac myocytes. Surprisingly, this activity was down-regulated by elevation of intracellular cAMP through a process involving PKA, but not EPAC, signalling. Such inhibition of the rodent PDE4A10 promoter activity in response to elevated cAMP levels is in contrast to the PDE4 promoters so far described. Site-directed mutagenesis revealed that the Sp1 binding site at promoter position -348 to -336 is responsible for the basal constitutive expression of murine PDE4A10. The conserved CREB-binding motif at position -370 to -363 also contributes to basal promoter activity but does not in itself confer cAMP inhibition upon the PDE4A10 promoter. EMSA analysis confirmed the authenticity of CREB and Sp1 binding sites. The transcriptional start site was identified to be an adenine residue at position -55 in the mouse PDE4A10 promoter. We present evidence that this novel down-regulation of PDE4A10 is mediated by the transcription factor ICER in a PKA dependent manner. The pool of cAMP in cardiac myocytes that down-regulates PDE4A10 is regulated by beta-adrenoceptor coupled adenylyl cyclase activity and via hydrolysis determined predominantly by the action of PDE4 (cAMP phosphodiesterase-4) and not PDE3 (cAMP phosphodiesterase-3). We suggest that increased cAMP may remodel cAMP-mediated signalling events by not only increasing the expression of specific PDE4 cAMP phosphodiesterases but also by down-regulating specific isoforms, such as is shown here for PDE4A10 in cardiac myocytes.
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Affiliation(s)
- Angela McCahill
- Neuroscience and Molecular Pharmacology, Wolfson Link and Davidson Buildings, Faculty of Biomedical & Life Sciences, University of Glasgow, University Avenue, Glasgow G12 8QQ, Scotland, UK
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Human PDE4A8, a novel brain-expressed PDE4 cAMP-specific phosphodiesterase that has undergone rapid evolutionary change. Biochem J 2008; 411:361-9. [PMID: 18095939 DOI: 10.1042/bj20071251] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We have isolated cDNAs encoding PDE4A8 (phosphodiesterase 4 isoform A8), a new human cAMP-specific PDE4 isoform encoded by the PDE4A gene. PDE4A8 has a novel N-terminal region of 85 amino acids that differs from those of the related 'long' PDE4A4, PDE4A10 and PDE4A11 isoforms. The human PDE4A8 N-terminal region has diverged substantially from the corresponding isoforms in the rat and other mammals, consistent with rapid evolutionary change in this region of the protein. When expressed in COS-7 cells, PDE4A8 localized predominantly in the cytosol, but approx. 20% of the enzyme was associated with membrane fractions. Cytosolic PDE4A8 was exquisitely sensitive to inhibition by the prototypical PDE4 inhibitor rolipram (IC(50) of 11+/-1 nM compared with 1600 nM for PDE4A4), but was less sensitive to inhibition by cilomilast (IC(50) of 101+/-7 nM compared with 61 nM for PDE4A4). PDE4A8 mRNA was found to be expressed predominantly in skeletal muscle and brain, a pattern that differs from the tissue expression of other human PDE4 isoforms and also from that of rat PDE4A8. Immunohistochemical analysis showed that PDE4A8 could be detected in discrete regions of human brain, including the cerebellum, spinal cord and cerebral cortex. The unique tissue distribution of PDE4A8, combined with the evolutionary divergence of its N-terminus, suggest that this isoform may have a specific function in regulating cAMP levels in human skeletal muscle and brain.
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Cullen MD, Cheung YF, Houslay M, Hartman TL, Watson KM, Buckheit RW, Pannecouque C, De Clercq E, Cushman M. Investigation of the alkenyldiarylmethane non-nucleoside reverse transcriptase inhibitors as potential cAMP phosphodiesterase-4B2 inhibitors. Bioorg Med Chem Lett 2008; 18:1530-3. [PMID: 18222088 PMCID: PMC2268889 DOI: 10.1016/j.bmcl.2007.12.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2007] [Revised: 12/02/2007] [Accepted: 12/06/2007] [Indexed: 11/25/2022]
Abstract
The alkenyldiarylmethanes (ADAMs) are currently being investigated as non-nucleoside HIV-1 reverse transcriptase inhibitors (NNRTIs) of potential value in the treatment of HIV infection and AIDS. During the course of these studies, a number of ADAM analogues have been identified that protect HIV-infected cells from the cytopathic effects of the virus by an unknown, HIV-1 RT-independent mechanism. Since the phosphodiesterase 4 family is required for HIV infection, the effect of various ADAMs on the activity of PDE4B2 was investigated in an effort to determine if the ADAMs could possibly be targeting phosphodiesterases. Six compounds representative of the ADAM class were tested for inhibition of cAMP hydrolysis by PDE4B2 enzymatic activity. Four ADAMs were found to be weak inhibitors of PDE4B2 and two of them were inactive. The experimental results are consistent with an antiviral mechanism that does not include inhibition of PDE4 isoforms.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Mark Cushman
- To whom correspondence should be addressed. . Phone: 765-494-1465. Fax: 765-494-6790
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Smith KJ, Baillie GS, Hyde EI, Li X, Houslay TM, McCahill A, Dunlop AJ, Bolger GB, Klussmann E, Adams DR, Houslay MD. 1H NMR structural and functional characterisation of a cAMP-specific phosphodiesterase-4D5 (PDE4D5) N-terminal region peptide that disrupts PDE4D5 interaction with the signalling scaffold proteins, beta-arrestin and RACK1. Cell Signal 2007; 19:2612-24. [PMID: 17900862 DOI: 10.1016/j.cellsig.2007.08.015] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2007] [Accepted: 08/26/2007] [Indexed: 01/29/2023]
Abstract
The unique 88 amino acid N-terminal region of cAMP-specific phosphodiesterase-4D5 (PDE4D5) contains overlapping binding sites conferring interaction with the signaling scaffold proteins, betaarrestin and RACK1. A 38-mer peptide, whose sequence reflected residues 12 through 49 of PDE4D5, encompasses the entire N-terminal RACK1 Interaction Domain (RAID1) together with a portion of the beta-arrestin binding site. (1)H NMR and CD analyses indicate that this region has propensity to form a helical structure. The leucine-rich hydrophobic grouping essential for RACK1 interaction forms a discrete hydrophobic ridge located along a single face of an amphipathic alpha-helix with Arg34 and Asn36, which also play important roles in RACK1 binding. The Asn22/Pro23/Trp24/Asn26 grouping, essential for RACK1 interaction, was located at the N-terminal head of the amphipathic helix that contained the hydrophobic ridge. RAID1 is thus provided by a distinct amphipathic helical structure. We suggest that the binding of PDE4D5 to the WD-repeat protein, RACK1, may occur in a manner akin to the helix-helix interaction shown for G(gamma) binding to the WD-repeat protein, G(beta). A more extensive section of the PDE4D5 N-terminal sequence (Thr11-Ala85) is involved in beta-arrestin binding. Several residues within the RAID1 helix contribute to this interaction however. We show here that these residues form a focused band around the centre of the RAID1 helix, generating a hydrophobic patch (from Leu29, Val30 and Leu33) flanked by polar/charged residues (Asn26, Glu27, Asp28, Arg34). The interaction with beta-arrestin exploits a greater circumference on the RAID1 helix, and involves two residues (Glu27, Asp28) that do not contribute to RACK1 binding. In contrast, the interaction of RACK1 with RAID1 is extended over a greater length of the helix and includes Leu37/Leu38, which do not contribute to beta-arrestin binding. A membrane-permeable, stearoylated Val12-Ser49 38-mer peptide disrupted the interaction of both beta-arrestin and RACK1 with endogenous PDE4D5 in HEKB2 cells, whilst a cognate peptide with a Glu27Ala substitution selectively failed to disrupt PDE4D5/RACK1 interaction. The stearoylated Val12-Ser49 38-mer peptide enhanced the isoprenaline-stimulated PKA phosphorylation of the beta(2)-adrenergic receptors (beta(2)AR) and its activation of ERK, whilst the Glu27Ala peptide was ineffective in both these regards.
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MESH Headings
- Adrenergic beta-2 Receptor Agonists
- Adrenergic beta-Agonists/pharmacology
- Amino Acid Sequence
- Arrestins/chemistry
- Arrestins/metabolism
- Binding Sites
- Cell Line
- Circular Dichroism
- Cyclic AMP-Dependent Protein Kinases/metabolism
- Cyclic Nucleotide Phosphodiesterases, Type 3
- Cyclic Nucleotide Phosphodiesterases, Type 4
- Epithelial Cells/drug effects
- Epithelial Cells/enzymology
- Epithelial Cells/metabolism
- GTP-Binding Proteins/chemistry
- GTP-Binding Proteins/metabolism
- Humans
- Hydrophobic and Hydrophilic Interactions
- Isoproterenol/pharmacology
- Models, Molecular
- Molecular Sequence Data
- Neoplasm Proteins/chemistry
- Neoplasm Proteins/metabolism
- Nuclear Magnetic Resonance, Biomolecular
- Peptides/pharmacology
- Phosphoric Diester Hydrolases/chemistry
- Phosphoric Diester Hydrolases/metabolism
- Phosphorylation
- Protein Binding
- Protein Structure, Secondary
- Protein Structure, Tertiary
- Receptors for Activated C Kinase
- Receptors, Adrenergic, beta-2/metabolism
- Receptors, Cell Surface/chemistry
- Receptors, Cell Surface/metabolism
- Signal Transduction
- beta-Arrestins
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Affiliation(s)
- K John Smith
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, PO Box 363, B15 2TT, UK
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26
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Vijayakrishnan L, Rudra S, Eapen MS, Dastidar S, Ray A. Small-molecule inhibitors of PDE-IV and -VII in the treatment of respiratory diseases and chronic inflammation. Expert Opin Investig Drugs 2007; 16:1585-99. [PMID: 17922623 DOI: 10.1517/13543784.16.10.1585] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Targeting phosphodiesterase IV (PDE-IV) with small-molecule inhibitors as a therapeutic for chronic inflammatory disorders has been an active area of research interest for many years. The major drawback, however, has been to develop pharmacophores that would differentiate between targeting isoforms of PDE-IV associated with inflammation, as opposed to those that cause emesis, a major side effect associated with PDE-IV inhibition. Several different approaches have been employed, including designing subtype selective PDE-IV inhibitors. A recent approach has been to develop chemotypes that target PDE-VII, a cAMP-specific PDE, expressed widely in immune and pro-inflammatory cells. It is hypothesized that dual inhibitors, which function to inhibit both PDE-IV and VII, may achieve a higher therapeutic index and thereby exhibit a lower propensity to cause adverse side effects that are characteristic when targeting PDE-IV alone. This review focuses on the major classes of compounds that are presently being studied for their potential to inhibit PDE-VII and discusses the available data in the development of dual PDE-IV and -VII inhibitors, their biologic activity and their scope as a therapeutic choice in chronic inflammatory diseases.
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Affiliation(s)
- Lalitha Vijayakrishnan
- Ranbaxy Laboratories Ltd, Department of Pharmacology, New Drug Discovery Research (R & D III), Plot No. 20, Sector-18, Gurgaon-122 001, India.
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27
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Cheung YF, Kan Z, Garrett-Engele P, Gall I, Murdoch H, Baillie GS, Camargo LM, Johnson JM, Houslay MD, Castle JC. PDE4B5, a Novel, Super-Short, Brain-Specific cAMP Phosphodiesterase-4 Variant Whose Isoform-Specifying N-Terminal Region Is Identical to That of cAMP Phosphodiesterase-4D6 (PDE4D6). J Pharmacol Exp Ther 2007; 322:600-9. [PMID: 17519386 DOI: 10.1124/jpet.107.122218] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The cAMP-specific phosphodiesterase-4 (PDE4) gene family is the target of several potential selective therapeutic inhibitors. The four PDE4 genes generate several distinct protein-coding isoforms through the use of alternative promoters and 5'-coding exons. Using mouse transcripts, we identified a novel, super-short isoform of human PDE4B encoding a novel 5' terminus, which we label PDE4B5. The protein-coding region of the novel 5' exon is conserved across vertebrates, chicken, zebrafish, and fugu. Reverse-transcription-polymerase chain reaction (PCR) and quantitative (PCR) measurements show that this isoform is brain-specific. The novel protein is 58 +/- 2 kDa; it has cAMP hydrolyzing enzymatic activity and is inhibited by PDE4-selective inhibitors rolipram and cilomilast (Ariflo). Confocal and subcellular fractionation analyses show that it is distributed predominantly and unevenly within the cytosol. The 16 novel N-terminal residues of PDE4B5 are identical to the 16 N-terminal residues of the super-short isoform of PDE4D (PDE4D6), which is also brain-specific. PDE4B5 is able to bind the scaffold protein DISC1, whose gene has been linked to schizophrenia. Microarray expression profiling of the PDE4 gene family shows that specific PDE4 genes are enriched in muscle and blood fractions; however, only by monitoring the individual isoforms is the brain specificity of the super-short PDE4D and PDE4B isoforms revealed. Understanding the distinct tissue specificity of PDE4 isoforms will be important for understanding phosphodiesterase biology and opportunities for therapeutic intervention.
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Affiliation(s)
- York-Fong Cheung
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow, Scotland, United Kingdom
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28
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Abstract
Cyclic AMP regulates a vast number of distinct events in all cells. Early studies established that its hydrolysis by cyclic nucleotide phosphodiesterases (PDEs) controlled both the magnitude and the duration of its influence. Recent evidence shows that PDEs also act as coincident detectors linking cyclic-nucleotide- and non-cyclic-nucleotide-based cellular signaling processes and are tethered with great selectively to defined intracellular structures, thereby integrating and spatially restricting their cellular effects in time and space. Although 11 distinct families of PDEs have been defined, and cells invariably express numerous individual PDE enzymes, a large measure of our increased appreciation of the roles of these enzymes in regulating cyclic nucleotide signaling has come from studies on the PDE4 family. Four PDE4 genes encode more than 20 isoforms. Alternative mRNA splicing and the use of different promoters allows cells the possibility of expressing numerous PDE4 enzymes, each with unique amino-terminal-targeting and/or regulatory sequences. Dominant negative and small interfering RNA-mediated knockdown strategies have proven that particular isoforms can uniquely control specific cellular functions. Thus the protein kinase A phosphorylation status of the beta(2) adrenoceptor and, thereby, its ability to switch its signaling to extracellular signal-regulated kinase activation, is uniquely regulated by PDE4D5 in cardiomyocytes. We describe how cardiomyocytes and vascular smooth muscle cells selectively vary both the expression and the catalytic activities of PDE4 isoforms to regulate their various functions and how altered regulation of these processes can influence the development, or resolution, of cardiovascular pathologies, such as heart failure, as well as various vasculopathies.
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MESH Headings
- 3',5'-Cyclic-AMP Phosphodiesterases/chemistry
- 3',5'-Cyclic-AMP Phosphodiesterases/metabolism
- A Kinase Anchor Proteins
- Adaptor Proteins, Signal Transducing/metabolism
- Animals
- Arrestins/metabolism
- Cardiovascular System/enzymology
- Cardiovascular System/metabolism
- Cyclic AMP/metabolism
- Cyclic Nucleotide Phosphodiesterases, Type 4
- Humans
- Isoenzymes/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/enzymology
- Myocytes, Cardiac/enzymology
- Myocytes, Smooth Muscle/enzymology
- Myocytes, Smooth Muscle/physiology
- Ryanodine Receptor Calcium Release Channel/metabolism
- Signal Transduction
- Vasoconstriction
- beta-Arrestins
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Affiliation(s)
- Miles D Houslay
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, UK.
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29
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Abstract
Contraction and relaxation of vascular smooth muscle and cardiac myocytes are key physiological events in the cardiovascular system. These events are regulated by second messengers, cAMP and cGMP, in response to extracellular stimulants. The strength of signal transduction is controlled by intracellular cyclic nucleotide concentrations, which are determined by a balance in production and degradation of cAMP and cGMP. Degradation of cyclic nucleotides is catalyzed by 3',5'-cyclic nucleotide phosphodiesterases (PDEs), and therefore regulation of PDEs hydrolytic activity is important for modulation of cellular functions. Mammalian PDEs are composed of 21 genes and are categorized into 11 families based on sequence homology, enzymatic properties, and sensitivity to inhibitors. PDE families contain many splice variants that mostly are unique in tissue-expression patterns, gene regulation, enzymatic regulation by phosphorylation and regulatory proteins, subcellular localization, and interaction with association proteins. Each unique variant is closely related to the regulation of a specific cellular signaling. Thus, multiple PDEs function as a particular modulator of each cardiovascular function and regulate physiological homeostasis.
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MESH Headings
- Animals
- Binding Sites
- Cyclic AMP/physiology
- Cyclic AMP-Dependent Protein Kinases/metabolism
- Cyclic GMP/physiology
- Female
- Gene Expression Regulation, Enzymologic
- Humans
- Isoenzymes/metabolism
- Male
- Mammals/metabolism
- Mice
- Mice, Knockout
- Mice, Transgenic
- Models, Biological
- Muscle Cells/enzymology
- Muscle Cells/physiology
- Muscle Contraction/physiology
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/enzymology
- Myocardial Contraction/physiology
- Myocytes, Cardiac/enzymology
- Myocytes, Cardiac/physiology
- Phenotype
- Phosphoproteins/metabolism
- Phosphoric Diester Hydrolases/classification
- Phosphoric Diester Hydrolases/genetics
- Phosphoric Diester Hydrolases/physiology
- Phosphorylation
- Phylogeny
- Protein Interaction Mapping
- Protein Kinases/physiology
- Protein Processing, Post-Translational/physiology
- Protein Structure, Tertiary
- Rats
- Signal Transduction/physiology
- Subcellular Fractions/enzymology
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Affiliation(s)
- Kenji Omori
- Discovery Research Laboratories, Tanabe Seiyaku Co Ltd, 2-50 Kawagishi 2-chome, Toda, Saitama 335-8505, Japan.
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30
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Hajjhussein H, Suvarna NU, Gremillion C, Judson Chandler L, O’Donnell JM. Changes in NMDA receptor-induced cyclic nucleotide synthesis regulate the age-dependent increase in PDE4A expression in primary cortical cultures. Brain Res 2007; 1149:58-68. [PMID: 17407767 PMCID: PMC2720317 DOI: 10.1016/j.brainres.2007.02.090] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2006] [Revised: 02/17/2007] [Accepted: 02/21/2007] [Indexed: 10/23/2022]
Abstract
NMDA receptor-induced cAMP and cGMP are selectively hydrolyzed by PDE4 and PDE2, respectively, in rat primary cerebral cortical and hippocampal cultures. Because cAMP levels regulate the expression of PDE4 in rat primary cortical cultures, we examined the manner in which NMDA receptor activity regulates the age-dependent increase in the expression of PDE4A observed in vivo and in vitro. Inhibiting the activity of NR2B subunit with ifenprodil blocked NMDA receptor-induced cGMP synthesis and increased NMDA receptor-induced cAMP levels in a manner that reduced PDE4 activity. Therefore, NR1/NR2B receptor-induced cGMP signaling is involved in an acute cross-talk regulation of NR1/NR2A receptor-induced cAMP levels, mediated by PDE4. Chronic inhibition of NMDA receptor activity with MK-801 reduced PDE4A1 and PDE4A5 expression and activity in a time-dependent manner; this effect was reversed by adding the PKA activator dbr-cAMP. Inhibiting GABA receptors with bicuculline increased NMDA receptor-induced cAMP synthesis and PDE4A expression in cultures treated between DIV 16 and DIV 21 but not in cultures treated between DIV 8 and DIV 13. This effect was due to a high tone of NMDA receptor-induced cGMP in younger cultures, which negatively regulated the expression of PDE4A by a PKG-mediated process. The present results are consistent with behavioral data showing that both PDE4 and PDE2 are involved in NMDA receptor-mediated memory processes.
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Affiliation(s)
- Hassan Hajjhussein
- Department of Pharmacology, University of Tennessee Health Science Center, Memphis, TN
| | - Neesha U. Suvarna
- Department of Pharmacology, University of Tennessee Health Science Center, Memphis, TN
| | - Carmen Gremillion
- Department of Pharmacology, Louisiana State University Health Sciences Center, Shreveport, LA
| | - L. Judson Chandler
- Departments of Physiology/Neuroscience and Psychiatry, Medical University of South Carolina, Charleston, SC
| | - James M. O’Donnell
- Departments of Behavioral Medicine & Psychiatry and Neurobiology & Anatomy, West Virginia University Health Sciences Center, Morgantown, WV
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31
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Stefan E, Wiesner B, Baillie GS, Mollajew R, Henn V, Lorenz D, Furkert J, Santamaria K, Nedvetsky P, Hundsrucker C, Beyermann M, Krause E, Pohl P, Gall I, MacIntyre AN, Bachmann S, Houslay MD, Rosenthal W, Klussmann E. Compartmentalization of cAMP-dependent signaling by phosphodiesterase-4D is involved in the regulation of vasopressin-mediated water reabsorption in renal principal cells. J Am Soc Nephrol 2006; 18:199-212. [PMID: 17135396 DOI: 10.1681/asn.2006020132] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The cAMP/protein kinase A (PKA)-dependent insertion of water channel aquaporin-2 (AQP2)-bearing vesicles into the plasma membrane in renal collecting duct principal cells (AQP2 shuttle) constitutes the molecular basis of arginine vasopressin (AVP)-regulated water reabsorption. cAMP/PKA signaling systems are compartmentalized by A kinase anchoring proteins (AKAP) that tether PKA to subcellular sites and by phosphodiesterases (PDE) that terminate PKA signaling through hydrolysis of localized cAMP. In primary cultured principal cells, AVP causes focal activation of PKA. PKA and cAMP-specific phosphodiesterase-4D (PDE4D) are located on AQP2-bearing vesicles. The selective PDE4 inhibitor rolipram increases AKAP-tethered PKA activity on AQP2-bearing vesicles and enhances the AQP2 shuttle and thereby the osmotic water permeability. AKAP18delta, which is located on AQP2-bearing vesicles, directly interacts with PDE4D and PKA. In response to AVP, PDE4D and AQP2 translocate to the plasma membrane. Here PDE4D is activated through PKA phosphorylation and reduces the osmotic water permeability. Taken together, a novel, compartmentalized, and physiologically relevant cAMP-dependent signal transduction module on AQP2-bearing vesicles, comprising anchored PDE4D, AKAP18delta, and PKA, has been identified.
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MESH Headings
- 3',5'-Cyclic-AMP Phosphodiesterases/antagonists & inhibitors
- 3',5'-Cyclic-AMP Phosphodiesterases/genetics
- 3',5'-Cyclic-AMP Phosphodiesterases/metabolism
- Adaptor Proteins, Signal Transducing/genetics
- Adaptor Proteins, Signal Transducing/metabolism
- Amino Acid Sequence
- Animals
- Aquaporin 2/metabolism
- Arginine Vasopressin/metabolism
- Arginine Vasopressin/pharmacology
- Cells, Cultured
- Cyclic AMP/metabolism
- Cyclic AMP-Dependent Protein Kinases/genetics
- Cyclic AMP-Dependent Protein Kinases/metabolism
- Cyclic Nucleotide Phosphodiesterases, Type 3
- Cyclic Nucleotide Phosphodiesterases, Type 4
- Humans
- Kidney Tubules, Collecting/cytology
- Kidney Tubules, Collecting/drug effects
- Kidney Tubules, Collecting/metabolism
- Models, Biological
- Molecular Sequence Data
- Phosphodiesterase Inhibitors/pharmacology
- Rats
- Rats, Sprague-Dawley
- Recombinant Proteins/antagonists & inhibitors
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Rolipram/pharmacology
- Sequence Homology, Amino Acid
- Signal Transduction
- Water/metabolism
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Affiliation(s)
- Eduard Stefan
- Leibniz-Institut für Molekulare Pharmakologie, Berlin, Germany
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32
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Huston E, Houslay TM, Baillie GS, Houslay MD. cAMP phosphodiesterase-4A1 (PDE4A1) has provided the paradigm for the intracellular targeting of phosphodiesterases, a process that underpins compartmentalized cAMP signalling. Biochem Soc Trans 2006; 34:504-9. [PMID: 16856845 DOI: 10.1042/bst0340504] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Specificity of cAMP signalling pathways has shown that the intracellular targeting of the individual components confers a three-dimensional context to the signalling paradigms in which they can exquisitely control the specificity of the outcome of the signal. Pivotal to this paradigm is degradation of cAMP by sequestered PDEs (phosphodiesterases). cAMP rapidly diffuses within cells and, without the action of spatially confined PDE populations, cAMP gradients could not be formed and shaped within cells so as to regulate targeted effector proteins. Of particular importance in regulating compartmentalized cAMP signalling are isoforms of the PDE4 family, which are individually defined by unique N-terminal regions. We have developed and pioneered the concept that a major function of this N-terminal region is to confer intracellular targeting of particular PDE4 isoforms on specific signalling complexes and intracellular locations. The paradigm for this concept developed from our original studies on the PDE4A1 (RD1) isoform. The N-terminal region unique to PDE4A1 consists of two well-defined helical regions separated by a mobile hinge region. Helix-2 provides the core membrane-insertion module, with helix-1 facilitating membrane association and fidelity of targeting in living cells. The irreversible, Ca(2+)-dependent insertion of the N-terminal region of PDE4A1 into membranes provides 'long-term' memory of cell activation.
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Affiliation(s)
- E Huston
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, UK
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33
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Bender AT, Beavo JA. Cyclic Nucleotide Phosphodiesterases: Molecular Regulation to Clinical Use. Pharmacol Rev 2006; 58:488-520. [PMID: 16968949 DOI: 10.1124/pr.58.3.5] [Citation(s) in RCA: 1317] [Impact Index Per Article: 73.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Cyclic nucleotide phosphodiesterases (PDEs) are enzymes that regulate the cellular levels of the second messengers, cAMP and cGMP, by controlling their rates of degradation. There are 11 different PDE families, with each family typically having several different isoforms and splice variants. These unique PDEs differ in their three-dimensional structure, kinetic properties, modes of regulation, intracellular localization, cellular expression, and inhibitor sensitivities. Current data suggest that individual isozymes modulate distinct regulatory pathways in the cell. These properties therefore offer the opportunity for selectively targeting specific PDEs for treatment of specific disease states. The feasibility of these enzymes as drug targets is exemplified by the commercial and clinical successes of the erectile dysfunction drugs, sildenafil (Viagra), tadalafil (Cialis), and vardenafil (Levitra). PDE inhibitors are also currently available or in development for treatment of a variety of other pathological conditions. In this review the basic biochemical properties, cellular regulation, expression patterns, and physiological functions of the different PDE isoforms will be discussed. How these properties relate to the current and future development of PDE inhibitors as pharmacological agents is especially considered. PDEs hold great promise as drug targets and recent research advances make this an exciting time for the field of PDE research.
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Affiliation(s)
- Andrew T Bender
- Department of Pharmacology, University of Washington Medical School, Health Sciences Building, Box 357280, Seattle, WA 98195-7280, USA
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34
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Bingham J, Sudarsanam S, Srinivasan S. Profiling human phosphodiesterase genes and splice isoforms. Biochem Biophys Res Commun 2006; 350:25-32. [PMID: 16987497 DOI: 10.1016/j.bbrc.2006.08.180] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2006] [Accepted: 08/28/2006] [Indexed: 11/29/2022]
Abstract
A mere 21 human phosphodiesterase (PDE) genes are responsible for modulating cellular levels of cAMP and cGMP in response to stimuli. Considering the importance of cAMP and cGMP to disparate physiological functions including visual response, smooth muscle relaxation, platelet aggregation, immune response, and cardiac contractibility, perhaps the 200 or more splice isoforms of PDE genes also play a major functional role. We profiled the human PDEs across 25 tissue samples using splice sensitive oligonucleotide microarrays containing probes for exons and exon-exon junctions. Our results suggest that PDEs exhibit tissue-specific differences in expression, as demonstrated by the high expression of PDE4B in skeletal muscle. At the splice variant level, the majority of PDE genes--notably 1A, 1C, 2A, 4C, 4D, 5A, 7A, 8A, 8B, 9A, 10A, and 11A--exhibited tissue-specific splicing with potential functional implications for PDE biology. This work validates expression of many EST transcripts, and confirms and expands on published findings based on PCR and cloning, illuminating some of the complexity of cAMP and cGMP processing.
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35
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Houslay MD, Schafer P, Zhang KYJ. Keynote review: phosphodiesterase-4 as a therapeutic target. Drug Discov Today 2006; 10:1503-19. [PMID: 16257373 DOI: 10.1016/s1359-6446(05)03622-6] [Citation(s) in RCA: 505] [Impact Index Per Article: 28.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Cyclic AMP (cAMP) is a key second messenger in all cells. It is compartmentalized within cells and its levels are controlled, as a result of spatially discrete signaling cassettes controlling its generation, detection and degradation. Underpinning compartmentalized cAMP signaling are approximately 20 members of the phosphodiesterase-4 (PDE4) family. The selective inhibition of this family generates profound, functional effects and PDE4 inhibitors are currently under development to provide potential, novel therapeutics for the treatment of inflammatory diseases, such as asthma, chronic obstructive pulmonary disease and psoriasis, as well as treating depression and serving as cognitive enhancers. Here, we delineate the range of PDE4 isoforms, their role in signaling, their structural biology and related preclinical and clinical pharmacology.
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Affiliation(s)
- Miles D Houslay
- Division of Biochemistry and Molecular Biology, IBLS, Wolfson Link Building, University of Glasgow, University Avenue, Glasgow, G12 8QQ, Scotland, UK.
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36
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Millen J, MacLean MR, Houslay MD. Hypoxia-induced remodelling of PDE4 isoform expression and cAMP handling in human pulmonary artery smooth muscle cells. Eur J Cell Biol 2006; 85:679-91. [PMID: 16458997 DOI: 10.1016/j.ejcb.2006.01.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Human pulmonary artery smooth muscle cells (hPASM cells) express PDE4A10, PDE4A11, PDE4B2, PDE4C and PDE4D5 isoforms. Hypoxia causes a transient up-regulation of PDE4B2 that reaches a maximum after 7 days and sustained up-regulation of PDE4A10/11 and PDE4D5 over 14 days in hypoxia. Seven days in hypoxia increases both intracellular cAMP levels, protein kinase A (PKA) activity and activated, phosphorylated extracellular signal regulated kinase (pERK) but does not alter either PKA isoform expression or total cAMP phosphodiesterase-4 (PDE4) activity or cAMP phosphodiesterase-3 (PDE3) activity. Both the cyclooxygenase inhibitor, indomethacin and the ERK inhibitors, UO126 and PD980589 reverse the hypoxia-induced increase in intracellular cAMP levels back to those seen in normoxic hPASM cells. Challenge of normoxic hPASM cells with prostaglandin E(2) (PGE(2)) elevates cAMP to levels comparable to those seen in hypoxic cells but fails to increase intracellular cAMP levels in hypoxic hPASM cells. The adenylyl cyclase activator, forskolin increases cAMP levels in both normoxic and hypoxic hPASM cells to comparable elevated levels. Challenge of hypoxic hPASM cells with indomethacin attenuates total PDE4 activity whilst challenge with UO126 increases total PDE4 activity. We propose that the hypoxia-induced activation of ERK initiates a phospholipase A(2)/COX-driven autocrine effect whereupon PGE(2) is generated, causing the activation of adenylyl cyclase and increase in intracellular cAMP. Despite the hypoxia-induced increases in the expression of PDE4A10/11, PDE4B2 and PDE4D5 and activation of certain of these long PDE4 isoforms through PKA phosphorylation, we suggest that the failure to see any overall increase in PDE4 activity is due to ERK-mediated phosphorylation and inhibition of particular PDE4 long isoforms. Such hypoxia-induced increase in expression of PDE4 isoforms known to interact with certain signalling scaffold proteins may result in alterations in compartmentalised cAMP signalling. The hypoxia-induced increase in cAMP may represent a compensatory protective mechanism against hypoxia-induced mitogens such as endothelin-1 and serotonin.
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Affiliation(s)
- Jennifer Millen
- Division of Neuroscience and Biomedical Systems, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, UK
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37
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D'Sa C, Eisch AJ, Bolger GB, Duman RS. Differential expression and regulation of the cAMP-selective phosphodiesterase type 4A splice variants in rat brain by chronic antidepressant administration. Eur J Neurosci 2006; 22:1463-75. [PMID: 16190900 DOI: 10.1111/j.1460-9568.2005.04321.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Chronic antidepressant treatment up-regulates the cAMP cascade in limbic brain regions, suggesting that activation of this pathway contributes to the therapeutic efficacy of antidepressants. A role for cAMP signaling is supported by the finding that rolipram, a selective inhibitor of cAMP-specific phosphodiesterases type 4 (PDE4), has antidepressant efficacy in behavioral models of depression and in clinical trials. To elucidate further the role of PDE4 isozymes, we characterized the expression and regulation of PDE4A splice variants (i.e. PDE4A1, PDE4A5, PDE4A8 and PDE4A10) in rat brain by chronic antidepressant treatment. Initial in situ hybridization studies (ISH) revealed high levels of PDE4A1 mRNA in medial septum, diagonal band, olfactory system, hippocampus and cerebellum. PDE4A5 mRNA expression was restricted to the olfactory nuclei, deep cortical layers, dentate and CA1 pyramidal layers. PDE4A10 mRNA was localized in the dentate gyrus and CA1 pyramidal layers. PDE4A8 mRNA was absent in rat brain. We determined the influence of chronic fluoxetine or electroconvulsive seizure (ECS) treatments on PDE4A splice variants expression in various brain regions. ISH analysis indicated that chronic fluoxetine or ECS treatments significantly increased PDE4A1, but not PDE4A5 or PDE4A10, mRNA levels in frontal and parietal cortices. ECS increased PDE4A5 levels in the anterior cingulate and frontoparietal cortices, CA1 and dentate gyrus, whereas chronic fluoxetine or ECS treatment increased PDE4A10 levels in the hippocampus. The differential up-regulation of PDE4A splice variants suggests compensatory region-specific responses to the antidepressant-induced increase in cAMP signaling and suggests that these splice variants may be relevant as targets for antidepressant intervention.
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Affiliation(s)
- Carrol D'Sa
- Department of Psychiatry and Pharmacology, Yale University School of Medicine, New Haven, CT 06508, USA.
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Guilpain P, Servettaz A, Tamby MC, Chanseaud Y, Le Guern V, Guillevin L, Mouthon L. Pathogénie des vascularites systémiques primitives (II): vascularites ANCA-négatives. Presse Med 2005; 34:1023-33. [PMID: 16225258 DOI: 10.1016/s0755-4982(05)84105-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The pathogenesis of different types of systemic vasculitis negative for antineutrophil cytoplasm antibodies (ANCA) and involving small or medium-sized vessels is not very well documented. During polyarteritis nodosa (PAN), which is related to hepatitis B virus (HBV) infection, as well as during cryoglobulinemic vasculitides, associated with hepatitis C virus (HCV), and probably during Henoch Schönlein purpura, histological lesions may result from the deposition of immune complexes formed from viral antigens and from antibodies responsible for the activation of the classic complement pathway and for recruitment of polymorphonuclear neutrophils. Two other mechanisms are discussed for other types of ANCA-negative systemic vasculitis: immune complex deposition and sheer stress at arterial bifurcation points. A bacterial superantigen is suspected in Kawasaki disease but remains unproved.
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Affiliation(s)
- P Guilpain
- Université Paris-Descartes, Faculté de médecine, UPRES EA 1833, site Cochin, Paris
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Houslay MD. The long and short of vascular smooth muscle phosphodiesterase-4 as a putative therapeutic target. Mol Pharmacol 2005; 68:563-7. [PMID: 15958394 DOI: 10.1124/mol.105.015719] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In this issue, Tilley and Maurice (p. 596) show that differentiation of vascular smooth muscle cells to a proliferative phenotype is associated with a profound up-regulation of specific phosphodiesterase-4 (PDE4) isoforms because of increased histone acetylation. The increased PDE4 activity is seen as preventing cAMP from inhibiting the enhanced proliferation, migration, and production of extracellular matrix seen in activated VSMC. This Perspective examines the proposal that selective inhibition of PDE4D1/2 could find use in adjunctive pharmacotherapy after percutaneous coronary interventions and, in addition, discusses the recent genetic evidence that PDE4D7 may provide a therapeutic target in stroke.
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Affiliation(s)
- Miles D Houslay
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, IBLS, Wolfson Building, University of Glasgow, Glasgow G12 8QQ, Scotland, UK.
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Tilley DG, Maurice DH. Vascular smooth muscle cell phenotype-dependent phosphodiesterase 4D short form expression: role of differential histone acetylation on cAMP-regulated function. Mol Pharmacol 2005; 68:596-605. [PMID: 15937214 DOI: 10.1124/mol.105.014126] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Sustained activation of adenylyl cyclase in vascular smooth muscle cells (VSMCs) results in the activation of a series of complex regulatory systems designed to desensitize these cells to further cAMP-mediated events. Although an increase in phosphodiesterase (PDE) 4-mediated hydrolysis of cAMP forms an integral part of this desensitization program in both "contractile/quiescent" and "synthetic/activated" VSMCs, distinct PDE4D gene variants coordinate these events in these phenotypically distinct cells. Using a combination of pharmacological, biochemical, and molecular biological approaches, and both in vivo and in vitro systems, we have identified the molecular basis underlying this VSMC phenotype-selective expression of PDE4D in response to cAMP-elevating agents in these cells. Thus, whereas the protein kinase A/cAMP response element-binding protein/cAMP response element signaling cascade regulates PDE4D expression in each VSMC phenotype, elevated levels of histone acetylation of the intronic promoter regulating PDE4D1 and PDE4D2 expression allows selective cAMP-mediated induction of expression of these PDE4D variants in synthetic/activated VSMCs. In contrast, the newly described EPAC1/Rap1A cAMP-dependent signaling cascade plays no role in regulating PDE4D expression in either VSMC phenotype. Our data are presented in the context of PDE4-mediated desensitization to cAMP-elevating agents in VSMCs and with the recognition that cAMP-elevating agents are being considered as adjunctive pharmacotherapy in percutaneous coronary interventions, including stenting.
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Affiliation(s)
- Douglas G Tilley
- Department of Pharmacology and Toxicology, Queen's University, Kingston, Ontario, Canada, K7L 3N6
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41
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Wallace DA, Johnston LA, Huston E, MacMaster D, Houslay TM, Cheung YF, Campbell L, Millen JE, Smith RA, Gall I, Knowles RG, Sullivan M, Houslay MD. Identification and characterization of PDE4A11, a novel, widely expressed long isoform encoded by the human PDE4A cAMP phosphodiesterase gene. Mol Pharmacol 2005; 67:1920-34. [PMID: 15738310 DOI: 10.1124/mol.104.009423] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
PDE4A11 is a novel cAMP-specific phosphodiesterase that is conserved in humans, mouse, rat, pig, and bat. Exon-1(4A11) encodes its unique, 81 amino acid N-terminal region. Reverse-transcriptase polymerase chain reaction performed across the splice junction, plus identification of expressed sequence tags, identifies PDE4A11 as a long isoform possessing UCR1 and UCR2 regulatory domains. Transcript analysis shows that PDE4A11 is widely expressed compared with PDE4A10 and PDE4A4B long isoforms. Truncation analysis identifies a putative promoter in a 250-base pair region located immediately upstream of the start site in Exon-1(4A11). Recombinant PDE4A11, expressed in COS-7 cells, is a 126-kDa protein localized predominantly around the nucleus and in membrane ruffles. PDE4A11 exhibits a K(m) for cAMP hydrolysis of 4 microM, with relative V(max) similar to that of PDE4A10 and PDE4A4B. PDE4A11 is dose-dependently inhibited by rolipram, 4-[(3-butoxy-4-methoxyphenyl)-methyl]-2-imidazolidinone (Ro 20-1724), cilomilast, roflumilast, and denbufylline, with IC(50) values of 0.7, 0.9, 0.03, 0.004, and 0.3 microM, respectively. Soluble and particulate PDE4A11 exhibit distinct rates of thermal inactivation (55 degrees C; T((0.5)) = 2.5 and 4.4 min, respectively). Elevating cAMP levels in COS-7 cells activates PDE4A11 concomitant with its phosphorylation at Ser119 by protein kinase A (PKA). PDE4A11 differs from PDE4A4 in sensitivity to cleavage by caspase-3, interaction with LYN SH3 domain, redistribution upon long-term rolipram challenge, and sensitivity to certain PDE4 inhibitors. PDE4A11, PDE4A10, and PDE4A4 all can interact with betaarrestin. PDE4A11 is a novel, widely expressed long isoform that is activated by PKA phosphorylation and shows a distinct intracellular localization, indicating that it may contribute to compartmentalized cAMP signaling in cells in which it is expressed.
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Affiliation(s)
- Derek A Wallace
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, Wolfson Building, University Avenue, University of Glasgow, Glasgow G12 8QQ, Scotland, UK
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42
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Leeb T, Müller M. Comparative human–mouse–rat sequence analysis of the ICAM gene cluster on HSA 19p13.2 and a 185-kb porcine region from SSC 2q. Gene 2004; 343:239-44. [PMID: 15588578 DOI: 10.1016/j.gene.2004.10.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2004] [Revised: 09/10/2004] [Accepted: 10/05/2004] [Indexed: 11/30/2022]
Abstract
The human intercellular adhesion molecule gene (ICAM) cluster is located in a GC-rich and gene-rich region on HSA 19p13.2. We determined the complete DNA sequence of a 185-kb porcine bacterial artificial chromosome (BAC) clone containing parts of the ICAM gene cluster. We used the porcine sequence for a detailed comparative analysis between human, pig, mouse and rat. The 185 kb of porcine sequence covered 220 kb of homologous sequence in the human genome, which adds to the growing evidence that the porcine genome is somewhat smaller than the human genome. The genomic sequences of the four species showed a high level of conserved synteny and no rearrangements in gene order were observed. During evolution, the ICAM3 gene was inactivated by mutation in the mouse and rat genome, whereas it is still present in the human and pig genome. The loss of Icam3 in rodent genomes might be relevant for rodent-specific properties of the T-cell-mediated immune response. All the other investigated genes are conserved across all four investigated sequences.
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Affiliation(s)
- Tosso Leeb
- Institute of Animal Breeding and Genetics, School of Veterinary Medicine Hannover, Bünteweg 17p, 30559 Hannover, Germany.
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Ahlström M, Pekkinen M, Huttunen M, Lamberg-Allardt C. Dexamethasone down-regulates cAMP-phosphodiesterase in human osteosarcoma cells. Biochem Pharmacol 2004; 69:267-75. [PMID: 15627479 DOI: 10.1016/j.bcp.2004.09.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2004] [Accepted: 09/17/2004] [Indexed: 11/17/2022]
Abstract
Cyclic adenosine monophosphate (cAMP) is an important second messenger in the hormonal regulation of bone metabolism. cAMP is inactivated by the cyclic nucleotide phosphodiesterases (PDEs), a superfamily of enzymes divided into 11 known families, designated PDE1-11. Interference with the cAMP signaling pathway has been suggested as one mechanism causing glucocorticoid induced osteoporosis. We speculated that glucocorticoids could affect the cAMP pathway by a down-regulation of PDE-mediated cAMP hydrolysis. The main cAMP hydrolysing enzyme families of human MG-63 and SaOS-2 osteosarcoma cells were identified as PDE1 and PDE4 by assaying the PDE activity of Q-sepharose fractions and cell homogenates with selective inhibitors. Treatment with the glucocorticoid dexamethasone (Dex) decreased cAMP-PDE activity by up to 50%, without affecting cGMP-PDE activity. Dex treatment reduced the sensitivity of the total cAMP-PDE activity towards the PDE4 selective PDE inhibitor rolipram. Forskolin stimulated cAMP accumulation was increased 30-60-fold in the presence of rolipram. Treatment with Dex did not affect the basal or forskolin stimulated cAMP accumulation, but treatment resulted in a reduced effect of rolipram on cAMP accumulation. Expression of the following cAMP-PDE subtypes were detected by reverse transcriptase PCR (RT-PCR): PDE1A, PDE1C, PDE2A, PDE3A, PDE4A, PDE4B, PDE4C, PDE4D, PDE7A, PDE7B, PDE8A, PDE10A and PDE11A. Using semi-quantitative RT-PCR, we detected a 50-70% decrease in the mRNA of PDE4A and PDE4B subtypes following Dex treatment. Further analysis revealed that Dex reduced the PDE4A4 and PDE4B1 isoforms. PDE4A1 PDE4A, PDE4A7, PDE4A10, PDE4B2 were also expressed, but Dex did not affect the transcription of these isoforms. We conclude that Dex treatment could affect the cAMP signaling pathway of human osteosarcoma cells by reducing type 4 cAMP-phosphodiesterase (PDE4).
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Affiliation(s)
- Mikael Ahlström
- Department of Applied Chemistry and Microbiology, University of Helsinki, P.O. Box 66, Helsinki 00014, Finland.
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Johnston LA, Erdogan S, Cheung YF, Sullivan M, Barber R, Lynch MJ, Baillie GS, Van Heeke G, Adams DR, Huston E, Houslay MD. Expression, intracellular distribution and basis for lack of catalytic activity of the PDE4A7 isoform encoded by the human PDE4A cAMP-specific phosphodiesterase gene. Biochem J 2004; 380:371-84. [PMID: 15025561 PMCID: PMC1224194 DOI: 10.1042/bj20031662] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2003] [Revised: 02/19/2004] [Accepted: 03/04/2004] [Indexed: 12/23/2022]
Abstract
PDE4A7 is an isoform encoded by the human PDE4A cAMP-specific phosphodiesterase gene that fails to hydrolyse cAMP and whose transcripts are widely expressed. Removal of either the N- or C-terminal unique portions of PDE4A7 did not reconstitute catalytic activity, showing that they did not exert a chronic inhibitory effect. A chimera (Hyb2), formed by swapping the unique N-terminal portion of PDE4A7 with that of the active PDE4A4C form, was not catalytically active. However, one formed (Hyb1) by swapping the unique C-terminal portion of PDE4A7 with that common to all active PDE4 isoforms was catalytically active. Compared with the active PDE4A4B isoform, Hyb1 exhibited a similar K(m) value for cAMP and IC50 value for rolipram inhibition, but was less sensitive to inhibition by Ro-20-1724 and denbufylline, and considerably more sensitive to thermal denaturation. The unique C-terminal region of PDE4A7 was unable to support an active catalytic unit, whereas its unique N-terminal region can. The N-terminal portion of the PDE4 catalytic unit is essential for catalytic activity and can be supplied by either highly conserved sequence found in active PDE4 isoforms from all four PDE4 subfamilies or the unique N-terminal portion of PDE4A7. A discrete portion of the conserved C-terminal region in active PDE4A isoforms underpins their aberrant migration on SDS/PAGE. Unlike active PDE4A isoforms, PDE4A7 is exclusively localized to the P1 particulate fraction in cells. A region located within the C-terminal portion of active PDE4 isoforms prevents such exclusive targeting. Three functional regions in PDE4A isoforms are identified, which influence catalytic activity, subcellular targeting and conformational status.
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Affiliation(s)
- Lee Ann Johnston
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Wolfson Building, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, UK
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45
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Sasaki T, Kotera J, Omori K. Transcriptional activation of phosphodiesterase 7B1 by dopamine D1 receptor stimulation through the cyclic AMP/cyclic AMP-dependent protein kinase/cyclic AMP-response element binding protein pathway in primary striatal neurons. J Neurochem 2004; 89:474-83. [PMID: 15056290 DOI: 10.1111/j.1471-4159.2004.02354.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Phosphodiesterase (PDE) 7B, a cAMP-specific PDE which is dominantly expressed in striatum, is expected to be involved in dopaminergic signaling in striatal neurons. Here we show, for the first time, the involvement of the dopaminergic signaling pathway in transcriptional activation of rat PDE7B in primary striatal culture. RT-PCR analysis revealed that dopamine, D1 agonist, forskolin and 8-Br-cAMP stimulation potentiated PDE7B transcription in striatal neurons, while D2 agonist failed to activate the PDE7B transcription. Pre-treatment with D1 antagonist abolished the dopamine- or D1 agonist-induced transcriptional activation of PDE7B. The activation of PDE7B transcription by these stimulators was completely ablated by pre-treatment of the cells with a cAMP-dependent protein kinase inhibitor, H-89. RT-PCR using splice variant-specific primers revealed that transcription of PDE7B1, but not of other splice variants, was activated by D1 agonist. We determined the putative transcription start site of PDE7B1, a brain-specific splice variant of PDE7B, by 5'-RACE and identified a promoter region of PDE7B1. Sequence analysis of the PDE7B1 promoter revealed the presence of a canonical cAMP-response element at 166 bp upstream of the putative transcription start site. The cAMP-responsiveness of the PDE7B1 promoter was demonstrated by functional promoter analysis using the luciferase reporter system. Deletion and mutation of the cAMP-response element site in the PDE7B1 promoter abolished the forskolin-induced activation of the PDE7B1 promoter activity. Electrophoretic mobility shift assay showed the binding of cAMP-response element binding protein to the PDE7B1 promoter. These data demonstrate the dopamine D1 receptor-mediated transcriptional activation of PDE7B through the cAMP/cAMP-dependent protein kinase/cAMP-response element binding protein pathway in striatal neurons.
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MESH Headings
- 3',5'-Cyclic-AMP Phosphodiesterases/genetics
- 3',5'-Cyclic-AMP Phosphodiesterases/metabolism
- 8-Bromo Cyclic Adenosine Monophosphate/pharmacology
- Alternative Splicing/genetics
- Animals
- Base Sequence
- Cells, Cultured
- Colforsin/pharmacology
- Cyclic AMP/metabolism
- Cyclic AMP Response Element-Binding Protein/metabolism
- Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors
- Cyclic AMP-Dependent Protein Kinases/metabolism
- Cyclic Nucleotide Phosphodiesterases, Type 7
- Dopamine/metabolism
- Dopamine/pharmacology
- Dopamine Agonists/pharmacology
- Dopamine Antagonists/pharmacology
- Enzyme Inhibitors/pharmacology
- Isoenzymes/genetics
- Isoenzymes/metabolism
- Molecular Sequence Data
- Neostriatum/cytology
- Neurons/drug effects
- Neurons/metabolism
- Promoter Regions, Genetic/drug effects
- Promoter Regions, Genetic/physiology
- Rats
- Rats, Wistar
- Receptors, Dopamine D1/agonists
- Receptors, Dopamine D1/antagonists & inhibitors
- Receptors, Dopamine D1/metabolism
- Signal Transduction/drug effects
- Signal Transduction/genetics
- Signal Transduction/physiology
- Transcriptional Activation/drug effects
- Transcriptional Activation/genetics
- Transcriptional Activation/physiology
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Affiliation(s)
- Takashi Sasaki
- Discovery and Pharmacology Research Laboratories, Tanabe Seiyaku Co., Ltd, Toda, Saitama, Japan
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Shepherd MC, Baillie GS, Stirling DI, Houslay MD. Remodelling of the PDE4 cAMP phosphodiesterase isoform profile upon monocyte-macrophage differentiation of human U937 cells. Br J Pharmacol 2004; 142:339-51. [PMID: 15066910 PMCID: PMC1574950 DOI: 10.1038/sj.bjp.0705770] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2003] [Revised: 02/13/2004] [Accepted: 03/01/2004] [Indexed: 11/08/2022] Open
Abstract
Monocytes and macrophages provide key targets for the action of novel anti-inflammatory therapeutics targeted at inhibition of PDE4 cAMP-specific phosphodiesterases. PDE4 enzymes provide the dominant cAMP phosphodiesterase activity in U937 human monocytic cells. Differentiation of U937 monocytic cells to a macrophage-like phenotype causes a marked reduction in total cellular PDE4 activity. Monocytic U937 cells express the long PDE4A4, PDE4D5 and PDE4D3 isoforms plus the short PDE4B2 isoform. Differentiation of U937 cells to a macrophage-like phenotype causes a marked downregulation of PDE4D3 and PDE4D5, elicits a marked upregulation of PDE4B2 and induces the novel PDE4A10 long isoform. Comparable patterns are found in human peripheral blood monocytes and macrophages differentiated from them. Immunopurification of PDE4 subfamilies identifies long PDE4D isoforms as providing the major PDE4 activity in U937 monocytic cells. In U937 macrophage-like cells, the activity of the short PDE4B2 isoform predominates. No indication of either the expression or induction of PDE4C was evident. Activation of ERK exerts an inhibitory effect on total PDE4 activity in monocytic U937 cells, where the activity of long PDE4 isoforms predominates. The effect of ERK activation is switched to one of overall stimulation of total PDE4 activity in macrophage U937 cells, where the activity of the short PDE4B2 isoform predominates.10 The profound differentiation-induced changes in PDE4 isoform profile identified here suggests that the development of inhibitors specific for particular PDE4 isoforms may allow for selective effects on monocytes and macrophages to be achieved.
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Affiliation(s)
- Malcolm C Shepherd
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical & Life Sciences, Wolfson Building, University Avenue, University of Glasgow, Glasgow G12 8QQ, Scotland
| | - George S Baillie
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical & Life Sciences, Wolfson Building, University Avenue, University of Glasgow, Glasgow G12 8QQ, Scotland
| | - David I Stirling
- Celgene Corporation, 7 Powder Horn Drive, Warren, NJ 07059, U.S.A
| | - Miles D Houslay
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical & Life Sciences, Wolfson Building, University Avenue, University of Glasgow, Glasgow G12 8QQ, Scotland
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47
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Bolger GB, Peden AH, Steele MR, MacKenzie C, McEwan DG, Wallace DA, Huston E, Baillie GS, Houslay MD. Attenuation of the activity of the cAMP-specific phosphodiesterase PDE4A5 by interaction with the immunophilin XAP2. J Biol Chem 2003; 278:33351-63. [PMID: 12810716 DOI: 10.1074/jbc.m303269200] [Citation(s) in RCA: 135] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The cyclic AMP-specific phosphodiesterase (PDE4) isoform PDE4A5 interacted with the immunophilin XAP2 in a yeast two-hybrid assay. The interaction was confirmed in biochemical pull-down analyses. The interaction was specific, in that PDE4A5 did not interact with the closely related immunophilins AIPL1, FKBP51, or FKBP52. XAP2 also did not interact with other PDE4A isoforms or typical isoforms from the three other PDE4 subfamilies. Functionally, XAP2 reversibly inhibited the enzymatic activity of PDE4A5, increased the sensitivity of PDE4A5 to inhibition by the prototypical PDE4 inhibitor 4-[3-(cyclopentyloxy)-4-methoxyphenyl]-2-pyrrolidinone (rolipram) and attenuated the ability of cAMP-dependent protein kinase to phosphorylate PDE4A5 in intact cells. XAP2 maximally inhibited PDE4A5 by approximately 60%, with an IC50 of 120 nm, and reduced the IC50 for rolipram from 390 nm to 70-90 nm. Co-expression of XAP2 and PDE4A5 in COS7 cells showed that they could be co-immunoprecipitated and also reduced both the enzymatic activity of PDE4A5 and its IC50 for rolipram. Native XAP2 and PDE4A5 could be co-immunoprecipitated from the brain. The isolated COOH-terminal half of XAP2 (amino acids 170-330), containing its tetratricopeptide repeat domain, but not the isolated NH2-terminal half (amino acids 1-169), containing the immunophilin homology region, similarly reduced PDE4A5 activity and its IC50 for rolipram. Mutation of Arg271 to alanine, in the XAP2 tetratricopeptide repeat region, attenuated its ability to both interact with PDE4A5 in two-hybrid assays and to inhibit PDE4A5 activity. Either the deletion of a specific portion of the unique amino-terminal region or specific mutations in the regulatory UCR2 domain of PDE4A5 attenuated its ability be inhibited by XAP2. We suggest that XAP2 functionally interacts with PDE4A5 in cells.
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Affiliation(s)
- Graeme B Bolger
- Veterans Affairs Medical Center, Huntsman Cancer Institute, Department of Medicine, Division of Oncology, University of Utah Health Sciences Center, Salt Lake City, Utah 84148, USA.
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48
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Houslay MD, Adams DR. PDE4 cAMP phosphodiesterases: modular enzymes that orchestrate signalling cross-talk, desensitization and compartmentalization. Biochem J 2003; 370:1-18. [PMID: 12444918 PMCID: PMC1223165 DOI: 10.1042/bj20021698] [Citation(s) in RCA: 580] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2002] [Revised: 11/13/2002] [Accepted: 11/22/2002] [Indexed: 11/17/2022]
Abstract
cAMP is a second messenger that controls many key cellular functions. The only way to inactivate cAMP is to degrade it through the action of cAMP phosphodiesterases (PDEs). PDEs are thus poised to play a key regulatory role. PDE4 cAMP-specific phosphodiesterases appear to have specific functions with selective inhibitors serving as potent anti-inflammatory agents. The recent elucidation of the structure of the PDE4 catalytic unit allows for molecular insight into the mode of catalysis as well as substrate and inhibitor selectivity. The four PDE4 genes encode over 16 isoforms, each of which is characterized by a unique N-terminal region. PDE4 isoforms play a pivotal role in controlling functionally and spatially distinct pools of cAMP by virtue of their unique intracellular targeting. Targeting occurs by association with proteins, such as arrestins, SRC family tyrosyl kinases, A-kinase anchoring proteins ('AKAPs') and receptor for activated C kinase 1 ('RACK1'), and, in the case of isoform PDE4A1, by a specific interaction (TAPAS-1) with phosphatidic acid. PDE4 isoforms are 'designed' to be regulated by extracellular-signal-related protein kinase (ERK), which binds to anchor sites on the PDE4 catalytic domain that it phosphorylates. The upstream conserved region 1 (UCR1) and 2 (UCR2) modules that abut the PDE4 catalytic unit confer regulatory functions by orchestrating the functional outcome of phosphorylation by cAMP-dependent protein kinase ('PKA') and ERK. PDE4 enzymes stand at a crossroads that allows them to integrate various signalling pathways with that of cAMP in spatially distinct compartments.
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Affiliation(s)
- Miles D Houslay
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Davidson Building, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, UK.
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49
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Le Jeune IR, Shepherd M, Van Heeke G, Houslay MD, Hall IP. Cyclic AMP-dependent transcriptional up-regulation of phosphodiesterase 4D5 in human airway smooth muscle cells. Identification and characterization of a novel PDE4D5 promoter. J Biol Chem 2002; 277:35980-9. [PMID: 12121997 DOI: 10.1074/jbc.m204832200] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Phosphodiesterase 4D (PDE4D), part of the complex cAMP-specific PDE4 family, plays a pivotal role in the regulation of airway smooth muscle relaxation by catalyzing the hydolysis of cAMP. Its gene on chromosome 5q12 encodes 5 splice variants, which show tissue-dependent expression and regulation. The genomic arrangement of PDE4D was determined using in silico methods, and a putative promoter of one of the protein kinase A-activated, long isoforms, PDE4D5 was identified. Promoter-luciferase constructs, transiently transfected into a beta(2) adrenoreceptor-expressing CHO-K1 cell line, were used to demonstrate that the PDE4D5 promoter up-regulated reporter gene expression in response to increased cell cAMP. Site-directed mutagenesis of the cAMP-response element (CRE) at position -201 identified this as the principal component of the mechanism underlying this cAMP responsiveness. In the second part of this study, cAMP-dependent induction of PDE4D5 transcript in primary cultured human airway smooth muscle cells (hASMs) was demonstrated using both qualitative reverse-transcriptase PCR and quantitative real-time PCR. Isolated PDE4D5 isoenzyme activity, measured after selective immunoprecipitation from hASMs, confirmed that this increase in expression led to an up-regulation of functional activity. We present evidence for cAMP-driven PDE4D5 up-regulation in hASMs and suggest a CRE-containing, isoform-specific promoter as the primary mechanism.
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MESH Headings
- 3',5'-Cyclic-AMP Phosphodiesterases/metabolism
- 8-Bromo Cyclic Adenosine Monophosphate/metabolism
- Alternative Splicing
- Animals
- Base Sequence
- CHO Cells
- Chromosomes, Human, Pair 5
- Cricetinae
- Culture Media, Serum-Free/pharmacology
- Cyclic AMP/metabolism
- Cyclic Nucleotide Phosphodiesterases, Type 3
- Cyclic Nucleotide Phosphodiesterases, Type 4
- Down-Regulation
- Genes, Reporter
- Humans
- Kinetics
- Luciferases/metabolism
- Models, Genetic
- Molecular Sequence Data
- Muscle, Smooth/cytology
- Mutagenesis, Site-Directed
- Phosphoric Diester Hydrolases/biosynthesis
- Phosphoric Diester Hydrolases/chemistry
- Precipitin Tests
- Promoter Regions, Genetic
- Protein Isoforms
- Protein Structure, Tertiary
- Reverse Transcriptase Polymerase Chain Reaction
- Trachea/cytology
- Transcription, Genetic
- Transfection
- Up-Regulation
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Affiliation(s)
- Ivan R Le Jeune
- Division of Therapeutics and Institute of Cell Signalling, University Hospital, Nottingham NG7 2UH, United Kingdom
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Affiliation(s)
- James V Donadio
- Division of Nephrology, Department of Medicine, Mayo Clinic and Mayo Foundation, Rochester, Minn 55905, USA.
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