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Cripps SM, Mattiske DM, Pask AJ. Erectile Dysfunction in Men on the Rise: Is There a Link with Endocrine Disrupting Chemicals? Sex Dev 2021; 15:187-212. [PMID: 34134123 DOI: 10.1159/000516600] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 04/18/2021] [Indexed: 11/19/2022] Open
Abstract
Erectile dysfunction (ED) is one of the most prevalent chronic conditions affecting men. ED can arise from disruptions during development, affecting the patterning of erectile tissues in the penis and/or disruptions in adulthood that impact sexual stimuli, neural pathways, molecular changes, and endocrine signalling that are required to drive erection. Sexual stimulation activates the parasympathetic system which causes nerve terminals in the penis to release nitric oxide (NO). As a result, the penile blood vessels dilate, allowing the penis to engorge with blood. This expansion subsequently compresses the veins surrounding the erectile tissue, restricting venous outflow. As a result, the blood pressure localised in the penis increases dramatically to produce a rigid erection, a process known as tumescence. The sympathetic pathway releases noradrenaline (NA) which causes detumescence: the reversion of the penis to the flaccid state. Androgen signalling is critical for erectile function through its role in penis development and in regulating the physiological processes driving erection in the adult. Interestingly, estrogen signalling is also implicated in penis development and potentially in processes which regulate erectile function during adulthood. Given that endocrine signalling has a prominent role in erectile function, it is likely that exposure to endocrine disrupting chemicals (EDCs) is a risk factor for ED, although this is an under-researched field. Thus, our review provides a detailed description of the underlying biology of erectile function with a focus on the role of endocrine signalling, exploring the potential link between EDCs and ED based on animal and human studies.
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Affiliation(s)
- Samuel M Cripps
- School of BioSciences, The University of Melbourne, Melbourne, Victoria, Australia
| | - Deidre M Mattiske
- School of BioSciences, The University of Melbourne, Melbourne, Victoria, Australia
| | - Andrew J Pask
- School of BioSciences, The University of Melbourne, Melbourne, Victoria, Australia
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Kodchakorn K, Viriyakhasem N, Wongwichai T, Kongtawelert P. Structural Determination, Biological Function, and Molecular Modelling Studies of Sulfoaildenafil Adulterated in Herbal Dietary Supplement. Molecules 2021; 26:949. [PMID: 33670094 PMCID: PMC7916901 DOI: 10.3390/molecules26040949] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/02/2021] [Accepted: 02/08/2021] [Indexed: 11/17/2022] Open
Abstract
Unapproved ingredients included in herbal medicines and dietary supplements have been detected as adulterated synthetic drugs used for erectile dysfunction. Extraction from a dietary supplement was performed to isolate the compounds by HPLC analysis. The structural characterization was confirmed using mass spectrometry (ESI-TOF/MS and LC-MS/MS), 1H NMR, and 13C NMR spectroscopy techniques. Results identified the thus-obtained compound to be sulfoaildenafil, a thioketone analogue of sildenafil. The biological activities of this active compound have been focused for the first time by the experimental point of view performance in vitro. The results revealed that sulfoaildenafil can affect the therapeutic level of nitric oxide through the upregulation of nitric oxide synthase and phosphodiesterase type 5 (PDE5) gene expressions. This bulk material, which displays structural similarity to sildenafil, was analyzed for the presence of a PDE5 inhibitor using a theoretical calculation. These unique features of the potential activity of PDE5 protein and its inhibitors, sildenafil and sulfoaildenafil, may play a key consideration for understanding the mode of actions and predicting the biological activities of PDE5 inhibitors.
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Affiliation(s)
- Kanchanok Kodchakorn
- Thailand Excellence Center for Tissue Engineering and Stem Cells, Department of Biochemistry, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand; (K.K.); (T.W.)
| | - Nawarat Viriyakhasem
- School of Traditional and Alternative Medicine, Chiang Rai Rajabhat University, Chiang Rai 57100, Thailand;
| | - Tunchanok Wongwichai
- Thailand Excellence Center for Tissue Engineering and Stem Cells, Department of Biochemistry, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand; (K.K.); (T.W.)
| | - Prachya Kongtawelert
- Thailand Excellence Center for Tissue Engineering and Stem Cells, Department of Biochemistry, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand; (K.K.); (T.W.)
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Tai LH, Alkayyal AA, Leslie AL, Sahi S, Bennett S, Tanese de Souza C, Baxter K, Angka L, Xu R, Kennedy MA, Auer RC. Phosphodiesterase-5 inhibition reduces postoperative metastatic disease by targeting surgery-induced myeloid derived suppressor cell-dependent inhibition of Natural Killer cell cytotoxicity. Oncoimmunology 2018; 7:e1431082. [PMID: 29872554 DOI: 10.1080/2162402x.2018.1431082] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 01/13/2018] [Accepted: 01/18/2018] [Indexed: 12/27/2022] Open
Abstract
Cancer surgery while necessary for primary tumor removal, has been shown to induce immune suppression and promote metastases in preclinical models and human cancer surgery patients. Activating the immune system and reversing immunosuppression have emerged as promising ways to treat cancer and they can be safely employed in the perioperative period. In this study, we evaluated the immunotherapeutic potential of phosphodiesterase-5 (PDE-5) inhibitors to target surgery-induced myeloid-derived suppressor cells (MDSC) and restore natural killer (NK) cell function in the clinically relevant perioperative period. Immunocompetent murine tumor models of major surgery were used to characterize the functional suppression of surgery-induced MDSC and to assess the in vivo efficacy of perioperative PDE5 inhibition. In cancer surgery patients with abdominal malignancies, we assessed postoperative NK cell function following co-culture with MDSC and PDE5 inhibition. Perioperative PDE5 inhibition reverses surgery-induced immunosuppression. In particular, sildenafil reduces surgery-derived granulocytic-MDSC (gMDSC) function through downregulation of arginase 1 (ARG1), IL4Ra and reactive oxygen species (ROS) expression, enabling NK cell antitumor cytotoxicity and reducing postoperative disease recurrence. By removing surgery-derived immunosuppressive mechanisms of MDSCs, sildenafil can be combined with the administration of perioperative influenza vaccination which targets NK cells to reduce postoperative metastasis. Importantly, sildenafil reverses MDSC suppression in cancer surgery patients. These findings demonstrate that PDE5 inhibitors reduce postoperative metastasis by their ability to inhibit surgery-induced MDSC. Further clinical studies are warranted to investigate the immunotherapeutic role of PDE5 inhibitors in combination with cancer surgery.
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Affiliation(s)
- Lee-Hwa Tai
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Almohanad A Alkayyal
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada.,Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, ON, Canada.,Department of Medical Laboratory Technology, University of Tabuk, Tabuk, Tabuk, Saudi Arabia
| | - Amanda L Leslie
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Shalini Sahi
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Sean Bennett
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada.,Department of Surgery, University of Ottawa, Ottawa, ON, Canada
| | | | - Katherine Baxter
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada.,Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Leonard Angka
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada.,Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Rebecca Xu
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Michael A Kennedy
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Rebecca C Auer
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada.,Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, ON, Canada.,Department of Surgery, University of Ottawa, Ottawa, ON, Canada
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Barone I, Giordano C, Bonofiglio D, Andò S, Catalano S. Phosphodiesterase type 5 and cancers: progress and challenges. Oncotarget 2017; 8:99179-99202. [PMID: 29228762 PMCID: PMC5716802 DOI: 10.18632/oncotarget.21837] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 09/23/2017] [Indexed: 01/05/2023] Open
Abstract
Cancers are an extraordinarily heterogeneous collection of diseases with distinct genetic profiles and biological features that directly influence response patterns to various treatment strategies as well as clinical outcomes. Nevertheless, our growing understanding of cancer cell biology and tumor progression is gradually leading towards rational, tailored medical treatments designed to destroy cancer cells by exploiting the unique cellular pathways that distinguish them from normal healthy counterparts. Recently, inhibition of the activity of phosphodiesterase type 5 (PDE5) is emerging as a promising approach to restore normal intracellular cyclic guanosine monophosphate (cGMP) signalling, and thereby resulting into the activation of various downstream molecules to inhibit proliferation, motility and invasion of certain cancer cells. In this review, we present an overview of the experimental and clinical evidences highlighting the role of PDE5 in the pathogenesis and prevention of various malignancies. Current data are still not sufficient to draw conclusive statements for cancer patient management, but could provide further rational for testing PDE5-targeting drugs as anticancer agents in clinical settings.
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Affiliation(s)
- Ines Barone
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Italy
| | - Cinzia Giordano
- Centro Sanitario, University of Calabria, Arcavacata di Rende, CS, Italy
| | - Daniela Bonofiglio
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Italy
| | - Sebastiano Andò
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Italy
| | - Stefania Catalano
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Italy
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Lescano CH, de Oliveira IP, Zaminelli T, Baldivia DDS, da Silva LR, Napolitano M, Silvério CBM, Lincopan N, Sanjinez-Argandoña EJ. Campomanesia adamantium Peel Extract in Antidiarrheal Activity: The Ability of Inhibition of Heat-Stable Enterotoxin by Polyphenols. PLoS One 2016; 11:e0165208. [PMID: 27764241 PMCID: PMC5072655 DOI: 10.1371/journal.pone.0165208] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 10/07/2016] [Indexed: 12/11/2022] Open
Abstract
Campomanesia adamantium (Myrtaceae) is a medicinal plant distributed in Brazilian Cerrado. Different parts of this plant are used in popular medicine for treatment of several diseases like fever, diarrhea, hypercholesterolemia and rheumatism. The aim of this work was to evaluate the inhibition of heat-stable enterotoxin type A (STa) by gallic acid present in the peel of C. adamantium fruit and assays to assess the antidiarrheal activity, anti-inflammatory and cytotoxic properties of peel extract using the T84 cell line model. The possible inhibition exerted by the gallic acid of the peel extract on the STa peptide was inferred by molecular dynamics simulations. The antidiarrheal effects were investigated measuring cGMP accumulation in cells after stimulation by STa toxin and antibacterial activity was assessed. The anti-inflammatory activity was assessed by inhibition of COX-1 and COX-2. MTT and LDH assays were used to evaluate any possible cytotoxic action while the CyQUANT test was used to investigate the effect on cell proliferation. A representation showing how the possible interactions between STa and the gallic acid of the extract might reduce the action of the enterotoxin is presented. C. adamantium peel extract significantly decreased the levels of cGMP in T84 cells. However, no effect on the species of microorganisms was observed. The extract also inhibited COX-1 (IC50 255.70 ± 0.04 ng/mL) and COX-2 (IC50 569.50 ± 0.11 ng/mL) enzymes. Cytotoxicity assay have shown significant changes in cells treated with the extract, which inhibited the cell proliferation until 72 hours of treatment. Direct interactions of phenolic compounds present in the extract with the STa toxin may limit its activity. Curative effect in the diarrhea treatment and its anti-inflammatory action is based on the pharmacological properties, mechanism of action of the C. adamantium peel extract, and no toxic effects of the peel extract presented on this work.
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Affiliation(s)
| | | | - Tiago Zaminelli
- Department of Pharmacology, University of Campinas, Campinas, São Paulo, Brazil
| | - Débora da Silva Baldivia
- Faculty of Biological and Environmental Sciences, Federal University of Grande Dourados, Dourados, Mato Grosso do Sul, Brazil
| | - Luan Ramos da Silva
- Faculty of Engineering, Federal University of Grande Dourados, Dourados, Mato Grosso do Sul, Brazil
| | - Mauro Napolitano
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, São Paulo, Brazil
| | | | - Nilton Lincopan
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, São Paulo, Brazil
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Peak TC, Richman A, Gur S, Yafi FA, Hellstrom WJG. The Role of PDE5 Inhibitors and the NO/cGMP Pathway in Cancer. Sex Med Rev 2016; 4:74-84. [PMID: 27872007 DOI: 10.1016/j.sxmr.2015.10.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 07/28/2015] [Indexed: 01/07/2023]
Abstract
INTRODUCTION Phosphodiesterase 5 (PDE5) inhibitors (PDE5i) have been used clinically for the treatment of erectile dysfunction, acting on the nitric oxide/cyclic guanosine monophosphate (NO/cGMP) signaling pathway. Simultaneously, researchers have elucidated the roles that this pathway plays in the regulation of cell proliferation, tumor development, and progression. As a result, our knowledge of PDE5i and cancer biology has expanded and provides an integration that holds great promise for some, but concern for others. AIM This review evaluates the role of PDE5i and the NO/cGMP signaling pathway in the pathogenesis and prevention of various malignancies. METHODS A literature review was performed with regard to the role of NO/cGMP pathway in tumor formation and prevention in preclinical and clinical studies. Studies that utilized PDE5i to further explore the involvement of this pathway also were included. MAIN OUTCOME MEASURES To evaluate whether PDE5i provide a potential benefit for treating and/or preventing malignancies; or if they create potential harm leading to the development of these malignancies. RESULTS The best available data suggest that the interactions between PDE5i and cancer are tumor- and tissue-specific. Currently, the effect of PDE5i use on melanoma development is being debated. Further clinical controversy lies in PDE5i use for penile rehabilitation after nerve-sparing prostate cancer surgery. Preclinical studies suggest that PDE5 inhibition could lead to a decreased risk of developing colorectal and breast cancer, leukemia, and myeloma. PDE5i also may provide an additional antitumor immune response. Finally, researchers have demonstrated a synergistic effect from combining PDE5i with current chemotherapeutic regimens. CONCLUSION Currently, there are inadequate data to make any conclusive statements regarding the role of PDE5i in cancer pathogenesis and how to alter clinical management. In order to create appropriate clinical guidelines, further experimental and clinical evidence is required.
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Affiliation(s)
- Taylor C Peak
- Department of Urology, Tulane University Health Sciences Center, New Orleans, LA, USA
| | - Ashley Richman
- Department of Urology, Tulane University Health Sciences Center, New Orleans, LA, USA
| | - Serap Gur
- Department of Pharmacology, School of Pharmacy, Ankara University, Ankara, Turkey
| | - Faysal A Yafi
- Department of Urology, Tulane University Health Sciences Center, New Orleans, LA, USA
| | - Wayne J G Hellstrom
- Department of Urology, Tulane University Health Sciences Center, New Orleans, LA, USA.
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7
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Giorgi M, Pompili A, Cardarelli S, Castelli V, Biagioni S, Sancesario G, Gasbarri A. Zaprinast impairs spatial memory by increasing PDE5 expression in the rat hippocampus. Behav Brain Res 2014; 278:129-36. [PMID: 25281278 DOI: 10.1016/j.bbr.2014.09.038] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 09/18/2014] [Accepted: 09/23/2014] [Indexed: 10/24/2022]
Abstract
In this work, we report the effect of post-training intraperitoneal administration of zaprinast on rat memory retention in the Morris water maze task that revealed a significant memory impairment at the intermediate dose of 10mg/kg. Zaprinast is capable of inhibiting both striatal and hippocampal PDE activity but to a different extent which is probably due to the different PDE isoforms expressed in these areas. To assess the possible involvement of cyclic nucleotides in rat memory impairment, we compared the effects obtained 30 min after the zaprinast injection with respect to 24h after injection by measuring both cyclic nucleotide levels and PDE activity. As expected, 30 min after the zaprinast administration, we observed an increase of cyclic nucleotides, which returned to a basal level within 24h, with the exception of the hippocampal cGMP which was significantly decreased at the dose of 10mg/kg of zaprinast. This increase in the hippocampal region is the result of a cGMP-specific PDE5 induction, confirmed by sildenafil inhibition, in agreement with literature data that demonstrate transcriptional regulation of PDE5 by cAMP/cGMP intracellular levels. Our results highlight the possible rebound effect of PDE inhibitors.
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Affiliation(s)
- Mauro Giorgi
- Department of Biology and Biotechnology "Charles Darwin", "Sapienza" University of Rome, Italy.
| | - Assunta Pompili
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Italy
| | - Silvia Cardarelli
- Department of Biology and Biotechnology "Charles Darwin", "Sapienza" University of Rome, Italy
| | - Valentina Castelli
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Italy
| | - Stefano Biagioni
- Department of Biology and Biotechnology "Charles Darwin", "Sapienza" University of Rome, Italy
| | - Giuseppe Sancesario
- Department of Systems Medicine, University of Rome "Tor Vergata", Italy; Fondazione Santa Lucia IRCCS, Rome, Italy
| | - Antonella Gasbarri
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Italy
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9
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Francis SH, Blount MA, Corbin JD. Mammalian Cyclic Nucleotide Phosphodiesterases: Molecular Mechanisms and Physiological Functions. Physiol Rev 2011; 91:651-90. [DOI: 10.1152/physrev.00030.2010] [Citation(s) in RCA: 451] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The superfamily of cyclic nucleotide (cN) phosphodiesterases (PDEs) is comprised of 11 families of enzymes. PDEs break down cAMP and/or cGMP and are major determinants of cellular cN levels and, consequently, the actions of cN-signaling pathways. PDEs exhibit a range of catalytic efficiencies for breakdown of cAMP and/or cGMP and are regulated by myriad processes including phosphorylation, cN binding to allosteric GAF domains, changes in expression levels, interaction with regulatory or anchoring proteins, and reversible translocation among subcellular compartments. Selective PDE inhibitors are currently in clinical use for treatment of erectile dysfunction, pulmonary hypertension, intermittent claudication, and chronic pulmonary obstructive disease; many new inhibitors are being developed for treatment of these and other maladies. Recently reported x-ray crystallographic structures have defined features that provide for specificity for cAMP or cGMP in PDE catalytic sites or their GAF domains, as well as mechanisms involved in catalysis, oligomerization, autoinhibition, and interactions with inhibitors. In addition, major advances have been made in understanding the physiological impact and the biochemical basis for selective localization and/or recruitment of specific PDE isoenzymes to particular subcellular compartments. The many recent advances in understanding PDE structures, functions, and physiological actions are discussed in this review.
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Affiliation(s)
- Sharron H. Francis
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee; and Department of Medicine-Renal Division, Emory University School of Medicine, Atlanta, Georgia
| | - Mitsi A. Blount
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee; and Department of Medicine-Renal Division, Emory University School of Medicine, Atlanta, Georgia
| | - Jackie D. Corbin
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee; and Department of Medicine-Renal Division, Emory University School of Medicine, Atlanta, Georgia
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Murray F, Maclean MR, Insel PA. Role of phosphodiesterases in adult-onset pulmonary arterial hypertension. Handb Exp Pharmacol 2011:279-305. [PMID: 21695645 DOI: 10.1007/978-3-642-17969-3_12] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Pulmonary arterial hypertension (PAH) is characterized by increased mean pulmonary artery pressure (mPAP) due to vasoconstriction and structural changes in the small pulmonary arteries (PAs); proliferation of pulmonary artery smooth muscle cells (PASMCs) contributes to the remodeling. The abnormal pathophysiology in the pulmonary vasculature relates to decreased cyclic nucleotide levels in PASMCs. Phosphodiesterases (PDEs) catalyze the hydrolysis of cAMP and cGMP, thereby PDE inhibitors are effective in vasodilating the PA and decreasing PASMC proliferation. Experimental studies support the use of PDE3, PDE5, and PDE1 inhibitors in PAH. PDE5 inhibitors such as sildenafil are clinically approved to treat different forms of PAH and lower mPAP, increase functional capacity, and decrease right ventricular hypertrophy, without decreasing systemic arterial pressure. New evidence suggests that the combination of PDE inhibitors with other therapies for PAH may be beneficial in treating the disease. Furthermore, inhibiting PDEs in the heart and the inflammatory cells that infiltrate the PA may offer new targets to reduce right ventricular hypertrophy and inhibit inflammation that is associated with and contributes to the development of PAH. This chapter summarizes the advances in the area and the future of PDEs in PAH.
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Affiliation(s)
- F Murray
- Department of Pharmacology and Department of Medicine, BSB 3073, University of California, 9500 Gilman Drive, La Jolla, San Diego, CA 92093-0636, USA.
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Francis SH, Busch JL, Corbin JD, Sibley D. cGMP-dependent protein kinases and cGMP phosphodiesterases in nitric oxide and cGMP action. Pharmacol Rev 2010; 62:525-63. [PMID: 20716671 DOI: 10.1124/pr.110.002907] [Citation(s) in RCA: 710] [Impact Index Per Article: 50.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
To date, studies suggest that biological signaling by nitric oxide (NO) is primarily mediated by cGMP, which is synthesized by NO-activated guanylyl cyclases and broken down by cyclic nucleotide phosphodiesterases (PDEs). Effects of cGMP occur through three main groups of cellular targets: cGMP-dependent protein kinases (PKGs), cGMP-gated cation channels, and PDEs. cGMP binding activates PKG, which phosphorylates serines and threonines on many cellular proteins, frequently resulting in changes in activity or function, subcellular localization, or regulatory features. The proteins that are so modified by PKG commonly regulate calcium homeostasis, calcium sensitivity of cellular proteins, platelet activation and adhesion, smooth muscle contraction, cardiac function, gene expression, feedback of the NO-signaling pathway, and other processes. Current therapies that have successfully targeted the NO-signaling pathway include nitrovasodilators (nitroglycerin), PDE5 inhibitors [sildenafil (Viagra and Revatio), vardenafil (Levitra), and tadalafil (Cialis and Adcirca)] for treatment of a number of vascular diseases including angina pectoris, erectile dysfunction, and pulmonary hypertension; the PDE3 inhibitors [cilostazol (Pletal) and milrinone (Primacor)] are used for treatment of intermittent claudication and acute heart failure, respectively. Potential for use of these medications in the treatment of other maladies continues to emerge.
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Affiliation(s)
- Sharron H Francis
- Department of Molecular Physiology & Biophysics, Vanderbilt University School of Medicine, 2215 Garland Avenue, Nashville, TN 37232-0615, USA.
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Andric SA, Janjic MM, Stojkov NJ, Kostic TS. Testosterone-induced modulation of nitric oxide-cGMP signaling pathway and androgenesis in the rat Leydig cells. Biol Reprod 2010; 83:434-42. [PMID: 20463352 DOI: 10.1095/biolreprod.110.083626] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Testosterone, acting as a systemic and local factor, is one of the major regulatory molecules that initiate and maintain testicular function. In the present study, different experimental approaches were used to evaluate the role of testosterone in regulation of the nitric oxide (NO)-cGMP pathway in Leydig cells derived from normal and hypogonadotropic male rats treated with testosterone for 24 h and 2 wk. Real-time quantitative PCR and Western blot analysis revealed increased inducible NO synthase (NOS2) expression followed by increased NO secretion from Leydig cells ex vivo after continuous treatment with testosterone for 2 wk in vivo. The cGMP-specific phosphodiesterases Pde5, Pde6, and Pde9 were up-regulated, whereas PRKG1 protein was decreased after a 2-wk testosterone treatment. Induction of Nos2 and Pde5 in Leydig cells was blocked by androgen receptor antagonist. In experimental hypogonadotropic hypogonadism, expression of NOS2 was significantly reduced, and treatment with testosterone increased NOS2 expression above control levels. PDE5 protein level was unchanged in hypogonadal rats, whereas treatment of hypogonadal rats with testosterone significantly increased it. In contrast, hypogonadism and testosterone replacement reduced PRKG1 protein in Leydig cells. In vitro treatment with testosterone caused gradually increased Nos2 gene expression followed by increased nitrite and cGMP production by purified Leydig cells. In summary, testosterone up-regulated NO signaling via increased NOS2 expression and contributed to down-regulation of cGMP signaling in Leydig cells. Thus, testosterone-induced modulation of NO-cGMP signaling may serve as a potent autocrine regulator of testicular steroidogenesis.
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Affiliation(s)
- Silvana A Andric
- Reproductive Endocrinology and Signaling Group, Department of Biology and Ecology, Faculty of Sciences, University of Novi Sad, Novi Sad, Serbia
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Farrow KN, Lakshminrusimha S, Czech L, Groh BS, Gugino SF, Davis JM, Russell JA, Steinhorn RH. SOD and inhaled nitric oxide normalize phosphodiesterase 5 expression and activity in neonatal lambs with persistent pulmonary hypertension. Am J Physiol Lung Cell Mol Physiol 2010; 299:L109-16. [PMID: 20400523 DOI: 10.1152/ajplung.00309.2009] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Phosphodiesterase 5 (PDE5) and soluble guanylate cyclase (sGC) are key regulators of cGMP and pulmonary vascular tone. We sought to determine the impact of mechanical ventilation with O(2) with or without inhaled nitric oxide (iNO) or recombinant human Cu/Zn SOD (rhSOD) on sGC, PDE5, and cGMP in the ovine ductal ligation model of persistent pulmonary hypertension of the newborn (PPHN). PPHN lambs were ventilated with 100% O(2) for 24 h alone or combined with either inhalation of 20 parts per million (ppm) iNO continuously or a single intratracheal dose of rhSOD (5 mg/kg). Ventilated PPHN lambs were compared with PPHN fetuses, control fetuses, and 1-day-old spontaneously breathing lambs (1DSB). In the small pulmonary arteries of 1DSB lambs, sGC expression increased, PDE5 expression decreased, and cGMP concentrations increased relative to fetal levels. In PPHN lambs ventilated with 100% O(2), sGC activity increased to levels comparable with 1DSB levels. However, PDE5 expression and activity increased, and cGMP levels remained at fetal levels. Addition of either iNO or rhSOD decreased PDE5 expression and activity in PPHN lambs and increased cGMP levels to levels comparable with 1DSB lambs. These data suggest that ventilation of PPHN lambs with 100% O(2) impairs cGMP-mediated vasodilation in part due to increased PDE5 expression and activity. The addition of either iNO or rhSOD normalized PDE5 and cGMP levels. Thus therapies designed to decrease PDE5 and increase cGMP, such as iNO and rhSOD, may prove useful in the treatment of PPHN in newborn infants.
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Affiliation(s)
- Kathryn N Farrow
- Dept. of Pediatrics, Northwestern Univ. Feinberg School of Medicine, 310 E. Superior St., Morton 4-685D, Chicago, IL 60611, USA.
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Balestrieri C, Alberghina L, Vanoni M, Chiaradonna F. Data recovery and integration from public databases uncovers transformation-specific transcriptional downregulation of cAMP-PKA pathway-encoding genes. BMC Bioinformatics 2009; 10 Suppl 12:S1. [PMID: 19828069 PMCID: PMC2762058 DOI: 10.1186/1471-2105-10-s12-s1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023] Open
Abstract
BACKGROUND The integration of data from multiple genome-wide assays is essential for understanding dynamic spatio-temporal interactions within cells. Such integration, which leads to a more complete view of cellular processes, offers the opportunity to rationalize better the high amount of "omics" data freely available in several public databases.In particular, integration of microarray-derived transcriptome data with other high-throughput analyses (genomic and mutational analysis, promoter analysis) may allow us to unravel transcriptional regulatory networks under a variety of physio-pathological situations, such as the alteration in the cross-talk between signal transduction pathways in transformed cells. RESULTS Here we sequentially apply web-based and statistical tools to a case study: the role of oncogenic activation of different signal transduction pathways in the transcriptional regulation of genes encoding proteins involved in the cAMP-PKA pathway. To this end, we first re-analyzed available genome-wide expression data for genes encoding proteins of the downstream branch of the PKA pathway in normal tissues and human tumor cell lines. Then, in order to identify mutation-dependent transcriptional signatures, we classified cancer cells as a function of their mutational state. The results of such procedure were used as a starting point to analyze the structure of PKA pathway-encoding genes promoters, leading to identification of specific combinations of transcription factor binding sites, which are neatly consistent with available experimental data and help to clarify the relation between gene expression, transcriptional factors and oncogenes in our case study. CONCLUSIONS Genome-wide, large-scale "omics" experimental technologies give different, complementary perspectives on the structure and regulatory properties of complex systems. Even the relatively simple, integrated workflow presented here offers opportunities not only for filtering data noise intrinsic in high throughput data, but also to progressively extract novel information that would have remained hidden otherwise. In fact we have been able to detect a strong transcriptional repression of genes encoding proteins of cAMP/PKA pathway in cancer cells of different genetic origins. The basic workflow presented herein may be easily extended by incorporating other tools and can be applied even by researchers with poor bioinformatics skills.
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Affiliation(s)
- Chiara Balestrieri
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, Milan, Italy.
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15
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Abstract
INTRODUCTION Penile detumescence depends on the hydrolysis of cyclic guanosine monophosphate (cGMP) by phosphodiesterase type 5 (PDE5). It is hoped that a review of publications relevant to the regulation of PDE5 in the penis will be helpful to both scientists and clinicians who are interested in the sciences of erectile function/dysfunction. AIMS The aim of this article is to comprehensively review the mechanisms by which PDE5 activity and expression in the penis are regulated. All published studies relevant to PDE5 regulation in the penis or penile cells will be reviewed. METHODS Entrez (PubMed) was used to search for publications relevant to the topics of this review. Keywords used in the searches included vascular, cavernous, penis, smooth muscle, signaling molecules, erection, priapism, and PDE5. Articles that are dedicated to the study of erectile function/dysfunction were prioritized for citation. RESULTS Regulation of PDE5 can occur at both protein and gene levels. At protein level, PDE5 is activated by phosphorylation and/or allosteric cGMP binding. Deactivation is carried out by protein phosphatase 1 and thus linked to the Rho-kinase signaling pathway. Cleavage of PDE5 into an inactive form has been shown as carried out by caspase-3. At the gene level, PDE5 expression is regulated at two alternative promoters, PDE5A and PDE5A2, both of which are positively regulated by cyclic adenosine monophosphate and cGMP. Downregulation of PDE5 has been observed in the penis of castrated animals; however, proof of androgen regulation of PDE5 gene requires examination of the smooth muscle content. Hyperoxia and hypoxia, respectively, regulate PDE5 expression positively and negatively. Hypoxic downregulation of PDE5 is a possible mechanism for the development of priapism. CONCLUSIONS PDE5 can be regulated at protein and gene levels. In the penis, changes of PDE5 activity have been linked to its phosphorylation status, and downregulation of PDE5 expression has been associated with hypoxia.
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Affiliation(s)
- Ching-Shwun Lin
- Knuppe Molecular Urology Laboratory, University of California, Department of Urology, San Francisco, CA 94115, USA.
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16
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Zhang H, Pakeerappa P, Lee HJ, Fisher SA. Induction of PDE5 and de-sensitization to endogenous NO signaling in a systemic resistance artery under altered blood flow. J Mol Cell Cardiol 2009; 47:57-65. [PMID: 19374906 DOI: 10.1016/j.yjmcc.2009.03.025] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2008] [Revised: 03/10/2009] [Accepted: 03/30/2009] [Indexed: 11/26/2022]
Abstract
In the classical pathway, the opposing activities of guanylyl cyclases (GC) and phosphodiesterases (PDE), and the effect of the cGMP-dependent protein kinase (cGK) on its targets, determine the biological responses to NO signaling. Here we tested the hypothesis that vascular dysfunction may be due to altered expression and activity of these effectors of NO signaling. Every other set of rat second order mesenteric resistance arteries (MA) were ligated, resulting in chronic low flow (LF) in the upstream MA1 and high flow (HF) in the adjacent MA1 without tissue ischemia. eNOS and iNOS were up-regulated in HF and LF MA1, respectively, in the sub-acute phase (four days) of vascular remodeling. The Day4 HF/LF MA1s were under increased control of NO as indicated by reduced sensitivity to the vasoconstrictor phenylephrine and its normalization with the NOS antagonist L-NAME. PDE5 mRNA and protein were also significantly up-regulated in the HF/LF MA1 with no change in sGC or PKG1, an effect that was dependent upon NO synthesis. The PDE5 inhibitor Sildenafil was several-fold more powerful in relaxing the HF/LF MA1s, and pre-treatment with Sildenafil uncovered an increased responsiveness of HF/LF MA1s to the NO donor DEA/NO. We conclude that induction of PDE5 de-sensitizes this systemic resistance artery to sustained NO signaling under chronic HF/LF. Treatment with PDE5 antagonists, in contrast to NO donors, may more specifically and effectively increase blood flow to chronically hypo-perfused tissues.
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Affiliation(s)
- Haiying Zhang
- Department of Medicine (Cardiology), Case Western Reserve School of Medicine, 4-533 Wolstein Research Bldg., 2103 Cornell Rd., Cleveland, OH 44106, USA
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17
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Dimitriadis F, Giannakis D, Pardalidis N, Zikopoulos K, Paraskevaidis E, Giotitsas N, Kalaboki V, Tsounapi P, Baltogiannis D, Georgiou I, Saito M, Watanabe T, Miyagawa I, Sofikitis N. Effects of phosphodiesterase-5 inhibitors on sperm parameters and fertilizing capacity. Asian J Androl 2008; 10:115-33. [PMID: 18087651 DOI: 10.1111/j.1745-7262.2008.00373.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The aim of this review study is to elucidate the effects that phosphodiesterase 5 (PDE5) inhibitors exert on spermatozoa motility, capacitation process and on their ability to fertilize the oocyte. Second messenger systems such as the cAMP/adenylate cyclase (AC) system and the cGMP/guanylate cyclase (GC) system appear to regulate sperm functions. Increased levels of intracytosolic cAMP result in an enhancement of sperm motility and viability. The stimulation of GC by low doses of nitric oxide (NO) leads to an improvement or maintenance of sperm motility, whereas higher concentrations have an adverse effect on sperm parameters. Several in vivo and in vitro studies have been carried out in order to examine whether PDE5 inhibitors affect positively or negatively sperm parameters and sperm fertilizing capacity. The results of these studies are controversial. Some of these studies demonstrate no significant effects of PDE5 inhibitors on the motility, viability, and morphology of spermatozoa collected from men that have been treated with PDE5 inhibitors. On the other hand, several studies demonstrate a positive effect of PDE5 inhibitors on sperm motility both in vivo and in vitro. In vitro studies of sildenafil citrate demonstrate a stimulatory effect on sperm motility with an increase in intracellular cAMP suggesting an inhibitory action of sildenafil citrate on a PDE isoform other than the PDE5. On the other hand, tadalafil's actions appear to be associated with the inhibitory effect of this compound on PDE11. In vivo studies in men treated with vardenafil in a daily basis demonstrated a significantly larger total number of spermatozoa per ejaculate, quantitative sperm motility, and qualitative sperm motility; it has been suggested that vardenafil administration enhances the secretory function of the prostate and subsequently increases the qualitative and quantitative motility of spermatozoa. The effect that PDE5 inhibitors exert on sperm parameters may lead to the improvement of the outcome of assisted reproductive technology (ART) programs. In the future PDE5 inhibitors might serve as adjunct therapeutical agents for the alleviation of male infertility.
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Affiliation(s)
- F Dimitriadis
- Department of Urology, Ioannina University School of Medicine, Ioannina 45110, Greece
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18
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Abstract
Phosphodiesterase type 5A (PDE5A) selectively hydrolyzes cyclic GMP. Inhibitors of PDE5A such as sildenafil are widely used to treat erectile dysfunction, but growing evidence supports important roles for the enzyme in both the vasculature and heart. In disorders such as cardiac failure, PDE5A upregulation may contribute to a decline in cGMP and protein kinase G signaling, exacerbating dysfunction. PDE5A plays an important role in the pulmonary vasculature where its inhibition benefits patients with pulmonary hypertension. In the heart, PDE5A signaling appears compartmentalized, and its inhibition is cardioprotective against ischemia-reperfusion and antracycline toxicity, blunts acute adrenergic contractile stimulation, and can suppress chronic hypertrophy and dysfunction attributable to pressure-overload. In this review, we discuss the molecular biology, pharmacology, and physiology of PDE5A, mechanisms of vascular and cardiac regulation, and recent evidence supporting the utility of selective PDE5A inhibition for the treatment of cardiovascular disorders.
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Affiliation(s)
- David A Kass
- Division of Cardiology, Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD 21205, USA.
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19
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Dlaboga D, Hajjhussein H, O'Donnell JM. Chronic haloperidol and clozapine produce different patterns of effects on phosphodiesterase-1B, -4B, and -10A expression in rat striatum. Neuropharmacology 2007; 54:745-54. [PMID: 18222493 DOI: 10.1016/j.neuropharm.2007.12.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2007] [Revised: 12/06/2007] [Accepted: 12/09/2007] [Indexed: 01/12/2023]
Abstract
Phosphodiesterase-10A (PDE10A), -1B (PDE1B), -4B (PDE4B), and -4A (PDE4A) are important regulators of signal transduction in striatum due to their catalysis of cyclic AMP and cyclic GMP. The typical antipsychotic drug haloperidol and the atypical antipsychotic drug clozapine are thought to regulate cyclic nucleotide signaling in striatum. Since this brain region is essential in mediation of both therapeutic and extrapyramidal side effects, it was of interest to determine whether chronic treatment for 21 days with haloperidol (1 mg/kg) or clozapine (20 mg/kg) affected PDE expression in rat striatum. This was accomplished using SDS-PAGE/immunoblotting and real-time RT-PCR. Both antipsychotic drugs increased PDE10A and did not change PDE4A. By contrast, PDE1B was increased by haloperidol treatment, but not clozapine treatment, while PDE4B was increased by clozapine, but not haloperidol. In all cases, changes in protein expression were accompanied by corresponding changes in mRNA, and only were observed with chronic treatment. Up-regulation of PDEs may represent compensatory responses to haloperidol and clozapine treatments, due to altered cyclic nucleotide signaling, and that different patterns of effects produced by these drugs may be associated with their mechanisms of action.
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Affiliation(s)
- Daniel Dlaboga
- Department of Behavioral Medicine & Psychiatry, West Virginia University Health Sciences Center, Morgantown, WV 26506, USA.
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20
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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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21
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Serafini P, Meckel K, Kelso M, Noonan K, Califano J, Koch W, Dolcetti L, Bronte V, Borrello I. Phosphodiesterase-5 inhibition augments endogenous antitumor immunity by reducing myeloid-derived suppressor cell function. ACTA ACUST UNITED AC 2006; 203:2691-702. [PMID: 17101732 PMCID: PMC2118163 DOI: 10.1084/jem.20061104] [Citation(s) in RCA: 578] [Impact Index Per Article: 32.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Phosphodiesterase-5 (PDE5) inhibitors (sildenafil, tadalafil, and vardenafil) are agents currently in clinical use for nonmalignant conditions. We report the use of PDE5 inhibitors as modulators of the antitumor immune response. In several mouse tumor models, PDE5 inhibition reverses tumor-induced immunosuppressive mechanisms and enables a measurable antitumor immune response to be generated that substantially delays tumor progression. In particular, sildenafil, down-regulates arginase 1 and nitric oxide synthase-2 expression, thereby reducing the suppressive machinery of CD11b+/Gr-1+ myeloid-derived suppressor cells (MDSCs) recruited by growing tumors. By removing these tumor escape mechanisms, sildenafil enhances intratumoral T cell infiltration and activation, reduces tumor outgrowth, and improves the antitumor efficacy of adoptive T cell therapy. Sildenafil also restores in vitro T cell proliferation of peripheral blood mononuclear cells from multiple myeloma and head and neck cancer patients. In light of the recent data that enzymes mediating MDSC-dependent immunosuppression in mice are active also in humans, these findings demonstrate a potentially novel use of PDE5 inhibitors as adjuncts to tumor-specific immune therapy.
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MESH Headings
- 3',5'-Cyclic-GMP Phosphodiesterases/antagonists & inhibitors
- 3',5'-Cyclic-GMP Phosphodiesterases/physiology
- Animals
- Antineoplastic Agents/pharmacology
- CD8-Positive T-Lymphocytes/drug effects
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/pathology
- Cell Differentiation/immunology
- Cell Line, Tumor
- Cyclic Nucleotide Phosphodiesterases, Type 5
- Melanoma, Experimental/enzymology
- Melanoma, Experimental/immunology
- Melanoma, Experimental/prevention & control
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Myeloid Cells/cytology
- Myeloid Cells/immunology
- Neoplasms/enzymology
- Neoplasms/immunology
- Neoplasms/prevention & control
- Phosphodiesterase Inhibitors/pharmacology
- T-Lymphocytes, Regulatory/enzymology
- T-Lymphocytes, Regulatory/immunology
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Affiliation(s)
- Paolo Serafini
- Sidney Kimmel Comprehensive Cancer Center, Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University, Baltimore, MD 21231, USA
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22
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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: 1331] [Impact Index Per Article: 73.9] [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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23
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Piggott LA, Hassell KA, Berkova Z, Morris AP, Silberbach M, Rich TC. Natriuretic peptides and nitric oxide stimulate cGMP synthesis in different cellular compartments. J Gen Physiol 2006; 128:3-14. [PMID: 16769793 PMCID: PMC2151547 DOI: 10.1085/jgp.200509403] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2005] [Accepted: 05/23/2006] [Indexed: 11/20/2022] Open
Abstract
Cyclic nucleotide-gated (CNG) channels are a family of ion channels activated by the binding of cyclic nucleotides. Endogenous channels have been used to measure cyclic nucleotide signals in photoreceptor outer segments and olfactory cilia for decades. Here we have investigated the subcellular localization of cGMP signals by monitoring CNG channel activity in response to agonists that activate either particulate or soluble guanylyl cyclase. CNG channels were heterologously expressed in either human embryonic kidney (HEK)-293 cells that stably overexpress a particulate guanylyl cyclase (HEK-NPRA cells), or cultured vascular smooth muscle cells (VSMCs). Atrial natriuretic peptide (ANP) was used to activate the particulate guanylyl cyclase and the nitric oxide donor S-nitroso-n-acetylpenicillamine (SNAP) was used to activate the soluble guanylyl cyclase. CNG channel activity was monitored by measuring Ca2+ or Mn2+ influx through the channels using the fluorescent dye, fura-2. We found that in HEK-NPRA cells, ANP-induced increases in cGMP levels activated CNG channels in a dose-dependent manner (0.05-10 nM), whereas SNAP (0.01-100 microM) induced increases in cGMP levels triggered little or no activation of CNG channels (P < 0.01). After pretreatment with 100 microM 3-isobutyl-1-methylxanthine (IBMX), a nonspecific phosphodiesterase inhibitor, ANP-induced Mn2+ influx through CNG channels was significantly enhanced, while SNAP-induced Mn2+ influx remained small. In contrast, we found that in the presence of IBMX, both 1 nM ANP and 100 microM SNAP triggered similar increases in total cGMP levels. We next sought to determine if cGMP signals are compartmentalized in VSMCs, which endogenously express particulate and soluble guanylyl cyclase. We found that 10 nM ANP induced activation of CNG channels more readily than 100 muM SNAP; whereas 100 microM SNAP triggered higher levels of total cellular cGMP accumulation. These results suggest that cGMP signals are spatially segregated within cells, and that the functional compartmentalization of cGMP signals may underlie the unique actions of ANP and nitric oxide.
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Affiliation(s)
- Leslie A Piggott
- Program in Cell and Regulatory Biology, The University of Texas Graduate School of Biomedical Sciences at Houston, 77225, USA
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Vernet D, Magee T, Qian A, Nolazco G, Rajfer J, Gonzalez-Cadavid N. Phosphodiesterase type 5 is not upregulated by tadalafil in cultures of human penile cells. J Sex Med 2006; 3:84-94; discussion 94-5. [PMID: 16409221 DOI: 10.1111/j.1743-6109.2005.00197.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Tadalafil, a long-acting phosphodiesterase type 5 (PDE5) inhibitor, improves the erectile response by inhibiting cyclic guanosine monophosphate (cGMP) breakdown. Sustained higher levels of cGMP may hypothetically upregulate PDE5 expression and/or activity and lead to tachyphylaxis. We have investigated whether PDE5 upregulation occurs in vitro in cultures of human penile cells subjected to long-term incubation with increasing concentrations of tadalafil in the presence of a nitric oxide (NO) donor. METHODS Human corpora cavernosa smooth muscle cells (CSMC) and tunica albuginea fibroblasts (TAF) primary cultures were characterized by immunocytochemistry and Western blot, and incubated with graded concentrations of tadalafil for 14 days, adding S-nitroso-N-acetyl penicillamine (SNAP) as an NO donor for the last 24 hours or at time zero, and cGMP levels were measured. Incubations were repeated for 7, 10, and 14 days, in the presence of SNAP, and PDE5 was estimated by Western blot, and at 14 days, by immunocytochemistry combined with quantitative image analysis, and by real-time reverse transcriptase polymerase chain reaction (RT-PCR). Constructs of the human PDE5A promoter expressing luciferase were cloned and transfected into CSMC, and promoter activation by 8-deoxybromo-cGMP (8-Br-cGMP) was measured by luminometry. RESULTS Incubations of CSMC with SNAP and tadalafil up to 14 days did not upregulate PDE5 mRNA or protein levels. With TAF, PDE5 protein was also not upregulated despite a slight increase in mRNA levels. PDE5 enzyme activity was unaffected by tadalafil in either CSMC or TAF. No upregulation of the PDE5 promoter was observed with up to 2 mM 8-Br-cGMP. CONCLUSIONS Long-term incubation of human penile cells with tadalafil at concentrations above the in vitro IC50, and around the in vivo Cmax utilized in the clinical setting, did not upregulate PDE5A expression nor decrease cGMP levels. These data suggest that PDE5 upregulation is unlikely to occur in vivo on long-term tadalafil treatment.
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Affiliation(s)
- Dolores Vernet
- Los Angeles Biomedical Research Institute-Urology, Torrance, CA, USA
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25
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Abstract
INTRODUCTION Penile erection depends on cavernous smooth muscle relaxation that is principally regulated by cyclic nucleotide signaling. It is hoped that a comprehensive review of publications relevant to this subject will be helpful to both scientists and clinicians who are interested in the sciences of erectile function/dysfunction. AIMS. To review the roles of extracellular signaling molecules, their receptors, intracellular effectors, and phosphodiesterases in cyclic nucleotide signaling that leads to cavernous smooth muscle relaxation. The involvement of these molecules in the development of erectile dysfunction and the possibility of using them as therapeutic agents or targets are also discussed. METHODS Entrez, the search engine for life sciences, was used to search for publications relevant to the topics of this review. Keywords used in the searches included vascular, cavernous, penis, smooth muscle, signaling molecules (adenosine, nitric oxide, etc.), and key elements in the cyclic nucleotide signaling pathways (cAMP, cGMP, cyclases, PKG, PKA, etc.). Articles that are dedicated to the study of erectile function/dysfunction were prioritized for citation. RESULTS More than 1,000 articles were identified, many of which are studies of the vascular system and are therefore reviewed but not cited. Studies on erectile function have identified both cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) signaling pathways in cavernous smooth muscle. Many signaling molecules of these two pathways have been shown capable of inducing erection when administered intracavernously. However, for sexually induced erection, nitric oxide (NO) is the responsible signaling molecule and it passes on the signal through soluble guanyl cyclase (sGC), cGMP, and protein kinase G (PKG). CONCLUSIONS The NO/sGC/cGMP/PKG pathway is principally responsible for sexually stimulated erection. Detumescence is mainly carried out by the degradation of cGMP by phosphodiesterase 5. Both cAMP and cGMP signaling pathways are susceptible to genetic and biochemical alterations in association with erectile dysfunction. Several key elements along these pathways are potential therapeutic targets.
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Affiliation(s)
- Ching-Shwun Lin
- Knuppe Molecular Urology Laboratory, Department of Urology, University of California, San Francisco, CA 94143-1695, USA.
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26
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Hwang TIS, Chen HE, Tsai TF, Lin YC. Combined use of androgen and sildenafil for hypogonadal patients unresponsive to sildenafil alone. Int J Impot Res 2006; 18:400-4. [PMID: 16395321 DOI: 10.1038/sj.ijir.3901446] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
To investigate the therapeutic effect of androgen on hypogonadal patients unresponsive to sildenafil alone. In total, 32 hypogonadal patients with erectile dysfunction (ED), initially had an inadequate response to sildenafil (100 mg). Oral testosterone undecanoate (Restandol, 80 mg, bid or tid) alone was supplied for 2 months, and if patients could not achieve a satisfactory erection, combined use of testosterone and sildenafil was continued thereafter. Total testosterone (TT), free testosterone (FT), and the parameters of the International Index of Erectile Function (IIEF), International Prostate Symptom Score (IPSS), and uroflow rate (UFR) were assessed. Eleven patients (34.3%) achieved satisfactory erectile function after testosterone replacement only. Another 12 (37.5%) patients experienced satisfactory intercourse after combined therapy. Serum TT and FT levels significantly increased after the use of testosterone alone (415+/-163 vs 220+/-101 ng/dl, P<0.01; 10.4+/-4.6 vs 5.1+/-1.9 ng/dl; P<0.01, respectively) and the combined use of testosterone and sildenafil (498+/-178 vs 220+/-101 ng/dl, P<0.01; 11.7+/-4.6 vs 5.1+/-1.9 ng/dl, P<0.001, respectively); as did the IIEF score (14.8+/-6.8 vs 12.6+/-7.5, P<0.01, 17.5+/-5.2 vs 12.6+/-7.5, P<0.001, respectively). However, no statistical differences were demonstrated for IPSS or UFR. In conclusions, one-third of hypogonadal patients with ED who failed to respond to sildenafil, responded to testosterone alone, another third responded to sildenafil again after normalization of testosterone. So, in hypogonadal patients with ED, androgen supplementation is first-line therapy. If patients are unresponsive to androgen alone or sildenafil alone, combined use may improve erectile function and enhance the therapeutic effect of PDE-5 inhibitors.
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Affiliation(s)
- T I-S Hwang
- Division of Urology, Department of Surgery, Shin Kong WHS Memorial Hospital, Taipei, Taiwan, ROC.
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27
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Lugnier C. Cyclic nucleotide phosphodiesterase (PDE) superfamily: a new target for the development of specific therapeutic agents. Pharmacol Ther 2005; 109:366-98. [PMID: 16102838 DOI: 10.1016/j.pharmthera.2005.07.003] [Citation(s) in RCA: 643] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2005] [Accepted: 07/12/2005] [Indexed: 01/08/2023]
Abstract
Cyclic nucleotide phosphodiesterases (PDEs), which are ubiquitously distributed in mammalian tissues, play a major role in cell signaling by hydrolyzing cAMP and cGMP. Due to their diversity, which allows specific distribution at cellular and subcellular levels, PDEs can selectively regulate various cellular functions. Their critical role in intracellular signaling has recently designated them as new therapeutic targets for inflammation. The PDE superfamily represents 11 gene families (PDE1 to PDE11). Each family encompasses 1 to 4 distinct genes, to give more than 20 genes in mammals encoding the more than 50 different PDE proteins probably produced in mammalian cells. Although PDE1 to PDE6 were the first well-characterized isoforms because of their predominance in various tissues and cells, their specific contribution to tissue function and their regulation in pathophysiology remain open research fields. This concerns particularly the newly discovered families, PDE7 to PDE11, for which roles are not yet established. In many pathologies, such as inflammation, neurodegeneration, and cancer, alterations in intracellular signaling related to PDE deregulation may explain the difficulties observed in the prevention and treatment of these pathologies. By inhibiting specifically the up-regulated PDE isozyme(s) with newly synthesized potent and isozyme-selective PDE inhibitors, it may be potentially possible to restore normal intracellular signaling selectively, providing therapy with reduced adverse effects.
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Affiliation(s)
- Claire Lugnier
- CNRS UMR, 7034, Pharmacologie et Physicochimie des Interactions Moléculaires et Cellulaires, Faculté de Pharmacie, Université Louis Pasteur de Strasbourg, 74 route du Rhin, BP 60024, 67401 Illkirch, France.
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Abstract
The cyclic nucleotide signalling pathway mediates the smooth-muscle relaxing effects of nitric oxide necessary for normal erectile function. Down-regulation of this pathway is central to the pathophysiology of many forms of erectile dysfunction (ED), which is often associated with other chronic diseases (e.g. hypertension, type 2 diabetes mellitus) and treatments (e.g. certain drugs, radical prostatectomy). Conversely, selective inhibition of the enzyme that catalyses the degradation of cGMP (phosphodiesterase type 5, PDE-5) promotes erectile responses to sexual stimulation. The successful launch and commercialization of the selective PDE5 inhibitor (PDE5I) sildenafil transformed the treatment of ED, not only by providing an effective, well tolerated oral ED therapy, but also by fostering greater candour about the problem among men. Sildenafil is highly effective in promoting erectile responses across a wide spectrum of severity and causes of ED, including patients with ED that is often refractory to treatment. The recent advent of vardenafil, which has the highest in vitro potency of all available PDE5Is, and tadalafil, which has a prolonged half-life that may enable couples to have sexual activity with less planning, represent further advances. Other PDE5Is offering further potential improvements are under active investigation.
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Affiliation(s)
- Culley C Carson
- Department of Surgery, Division of Urology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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Wharton J, Strange JW, Møller GMO, Growcott EJ, Ren X, Franklyn AP, Phillips SC, Wilkins MR. Antiproliferative effects of phosphodiesterase type 5 inhibition in human pulmonary artery cells. Am J Respir Crit Care Med 2005; 172:105-13. [PMID: 15817798 DOI: 10.1164/rccm.200411-1587oc] [Citation(s) in RCA: 239] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Phosphodiesterase Type 5 (PDE5) inhibition represents a novel strategy for the treatment of pulmonary hypertension. OBJECTIVES Our aim was to establish the distribution of PDE5 in the pulmonary vasculature and effects of PDE5 inhibition on pulmonary artery smooth muscle cells (PASMCs). METHODS AND MEASUREMENTS PDE5 expression was examined by immunohistochemistry and Western blotting, in both normal and hypertensive lung tissues. DNA synthesis, proliferation, PDE activity, and apoptosis were measured in distal human PASMCs treated with soluble guanylyl cyclase activators (nitric oxide donors and BAY41-2272) and sildenafil. MAIN RESULTS Cells containing PDE5 and alpha-smooth muscle actin occurred throughout the pulmonary vasculature, including obstructive intimal lesions. Three molecular forms of PDE5 were identified and protein expression was greater in hypertensive than control lung tissue. Most cyclic guanosine monophosphate hydrolysis (about 80%) in cultured cells was attributed to PDE5. Sildenafil induced a greater elevation of intracellular cyclic guanosine monophosphate levels compared with nitric oxide donors and BAY41-2272 (about 10-fold versus about 2-fold) and cotreatment had a synergistic effect, increasing cyclic nucleotide levels up to 50-fold. Dual stimulation of soluble guanylyl cyclase and inhibition of PDE5 activities also had significant downstream effects, increasing phosphorylation of vasodilator-stimulated phosphoprotein, reducing DNA synthesis and cell proliferation, and stimulating apoptosis, and these effects were mimicked by cyclic guanosine monophosphate analogs. CONCLUSIONS Phosphodiesterase Type 5 is the main factor regulating cyclic guanosine monophosphate hydrolysis and downstream signaling in human PASMCs. The antiproliferative effects of this signaling pathway may be significant in the chronic treatment of pulmonary hypertension with PDE5 inhibitors such as sildenafil.
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Affiliation(s)
- John Wharton
- Section on Experimental Medicine and Toxicology, Imperial College London, Hammersmith Campus, Du Cane Road, London W12 ONN, UK.
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30
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Abstract
Phosphodiesterase 5 (PDE5) has been identified in many species. The three isoforms, PDE5A1, PDE5A2, and PDE5A3, differ only in their N-terminal sequence. PDE5A1 and PDE5A2 are ubiquitous, but PDE5A3 is specific to smooth muscle. The initial three exons (A1-A3-A2) of PDE5A, located on chromosome 4q26, are alternative first exons encoding the isoform-specific sequences. The PDE5A promoter overlaps with the A1-specific exon, while the PDE5A2 promoter is located between the A3- and A2-specific exons. Both respond to cyclic guanosine monophosphate (cGMP) or cyclic adenosine monophosphate (cAMP) stimulation. The PDE5A2 promoter contains an Sp1-binding sequence critical for basal and cGMP/cAMP-inducible promoter activities. PDE5A is induced by adjacent sequences (enhancers) containing Sp1-binding sites. The potential role of PDE5A promoters in the tachyphylaxis effect of PDE5 inhibitors is currently being investigated. Preliminary data suggest that hypoxia might down-regulate PDE5A promoters, implying an involvement of PDE5 in stuttering priapism.
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Affiliation(s)
- C-S Lin
- Department of Urology, University of California, San Francisco, CA 94115, USA.
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31
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Hu H, McCaw EA, Hebb ALO, Gomez GT, Denovan-Wright EM. Mutant huntingtin affects the rate of transcription of striatum-specific isoforms of phosphodiesterase 10A. Eur J Neurosci 2004; 20:3351-63. [PMID: 15610167 DOI: 10.1111/j.1460-9568.2004.03796.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Huntington's disease (HD) is caused by the inheritance of a copy of the gene encoding mutant huntingtin with an expanded CAG repeat. Phosphodiesterase 10A (PDE10A) mRNA decreases in transgenic HD mice expressing exon 1 of the human huntingtin gene (HD). The mouse PDE10A mRNA is expressed through alternative splicing and polyadenylation in a tissue-specific manner and that transcription of striatal PDE10A mRNA is driven by two promoters. PDE10A2 is the predominant isoform of the gene is expressed in the striatum. Using in situ hybridization and quantitative RT-PCR, we determined that decreased steady-state levels of PDE10A2 mRNA were caused by an altered transcription initiation rate rather than by post-transcriptional mRNA instability in HD mice. Transcription from three initiation sites located within a 50-bp region in the PDE10A2-specific promoter was differentially affected by the presence of the mutant huntingtin transgene. The mouse and human PDE10A2 promoters are highly conserved with respect to the relative position of cis-regulatory elements. Several transcription factors that have been shown to interact with mutant huntingtin, including Sp1, neuron restrictive silencing factor, TATA-binding protein and cAMP-response element binding protein, are unlikely to be involved in mutant huntingtin-induced PDE10A2 transcriptional dysregulation.
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Affiliation(s)
- Haibei Hu
- Laboratory of Molecular Neurobiology, Department of Pharmacology, Dalhousie University, Canada B3H 1X5
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Salvi F, Sarzani R, Giorgi R, Donatelli G, Pietrucci F, Micheli A, Baldoni M, Minardi D, Minaroli D, Dessì-Fulgheri P, Polito M, Muzzonigro G, Rappelli A. Cardiovascular effects of sildenafil in hypertensive men with erectile dysfunction and different alleles of the type 5 cGMP-specific phosphodiesterase (PDE5). Int J Impot Res 2004; 16:412-7. [PMID: 15175637 DOI: 10.1038/sj.ijir.3901246] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Erectile dysfunction (ED) is frequent in patients with essential hypertension (EH); a likely common pathogenetic pathway could be a reduced ability of arteriolar vascular smooth muscle (VSM) to relax. Increasing intracellular levels of cGMP reduce the contractile status of VSM; on the contrary, type 5 cGMP-specific phosphodiesterase (PDE5, codified by PDE5A gene) regulates cGMP levels through its clearance. The PDE5A gene represents a good candidate for the intermediate phenotype EH/ED: genetic variants of the PDE5A may predispose to EH and ED and could affect the local and systemic response to sildenafil administration. Thus, a functionally relevant portion of PDE5 5'-flanking promoter region was analyzed by PCR and direct sequencing in patients with EH and idiopathic ED. The sequences obtained showed a T/G polymorphism at position -1142, near an AP1 regulatory element, that was not apparently associated with the intermediate phenotype. We also studied the relationship between this polymorphism and the effects of oral sildenafil on blood pressure (BP) and heart rate (HR) in men with ED. Sildenafil caused a significant decrease of BP, but had no effects on HR; statistical analysis showed no differences in BP and HR variations among PDE5A genotypes. In conclusion, our data showed no correlations of a novel polymorphism of the PDE5A promoter gene with the intermediate phenotype EH/ED and the BP and HR response to sildenafil administration. Further studies are necessary to define the role of this polymorphism and to study the genetic predisposition for EH with ED.
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Affiliation(s)
- F Salvi
- Department of Internal Medicine, Polytechnical University of Marche, Ancona, Italy.
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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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Aversa A, Isidori AM, Spera G, Lenzi A, Fabbri A. Androgens improve cavernous vasodilation and response to sildenafil in patients with erectile dysfunction. Clin Endocrinol (Oxf) 2003; 58:632-8. [PMID: 12699447 DOI: 10.1046/j.1365-2265.2003.01764.x] [Citation(s) in RCA: 205] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
OBJECTIVES We have recently shown that, in men with erectile dysfunction (ED), free testosterone (FT) directly correlates with penile arterial inflow. This led us to further investigate the effect(s) of androgen administration on cavernous arteries in patients failing sildenafil treatment. DESIGN Prospective randomized placebo-controlled pilot study. PATIENTS Twenty patients with arteriogenic ED as evaluated by dynamic colour duplex ultrasound (D-CDU) studies, normal sexual desire but testosterone (T) and FT in the lower quartile of normal range (low-normal), not responding to sildenafil treatment (100 mg) on six consecutive attempts. MEASUREMENTS All patients had D-CDU, hormonal [LH, prostate-specific antigen (PSA), total and free testosterone, sex hormone-binding protein (SHBG), oestradiol], biochemical [haematocrit, low-density lipoprotein (LDL) and HDL cholesterol, triglycerides], and sexual evaluations [International Index of Erectile Function (IIEF)] before and after 1 month of therapy with transdermal testosterone (5 mg/day, n = 10) or placebo along with sildenafil treatment on demand. Measurement of flow parameters by D-CDU on cavernous arteries was the primary endpoint of the study. Improvement of erectile function was assessed using the IIEF questionnaire and the Global Assessment Question (GAQ). RESULTS One month treatment with transdermal testosterone led to a significant increase in T and FT levels (23.7 +/- 3.3 SD vs. 12.8 +/- 2.1 nmol/l and 473 +/- 40.2 vs. 260 +/- 18.1 pmol/l, P < 0.01, respectively). In addition testosterone administration induced a significant increase in arterial inflow to cavernous arteries measured by D-CDU (32 +/- 3.6 vs. 25.2 +/- 4 cm/s, P < 0.05), with no adverse effects. Also, a significant improvement in erectile function domain score at IIEF was found in the androgen but not in the placebo-treated patients (21.8 +/- 2.1 vs. 14.4 +/- 1.4, P < 0.05) which was associated with significant changes in the GAQ score (80%vs. 10%, P < 0.01). CONCLUSIONS In patients with arteriogenic ED and low-normal androgen levels, short-term testosterone administration increases T and FT levels and improves the erectile response to sildenafil likely by increasing arterial inflow to the penis during sexual stimulation.
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Affiliation(s)
- Antonio Aversa
- AFaR-CRCCS, Ospedale Fatebenefratelli Isola Tiberina, Rome, Italy.
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Gavrilyuk V, Dello Russo C, Heneka MT, Pelligrino D, Weinberg G, Feinstein DL. Norepinephrine increases I kappa B alpha expression in astrocytes. J Biol Chem 2002; 277:29662-8. [PMID: 12050158 DOI: 10.1074/jbc.m203256200] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The neurotransmitter norepinephrine (NE) can inhibit inflammatory gene expression in glial cells; however, the mechanisms involved are not clear. In primary astrocytes, NE dose-dependently increased the expression of inhibitory I kappa B alpha protein accompanied by an increase in steady state levels of I kappa B alpha mRNA. Maximal increases were observed at 30-60 min for the mRNA and at 4 h for protein, and these effects were mediated by NE binding to beta-adrenergic receptors. NE activated a 1.3-kilobase I kappa B alpha promoter transfected into astrocytes or C6 glioma cells, and this activation was prevented by a beta-antagonist and by protein kinase A inhibitors but not by an NF kappa B inhibitor. NE increased I kappa B alpha protein in both the cytosolic and the nuclear fractions, suggesting an increase in nuclear uptake of I kappa B alpha. I kappa B alpha was detected in the frontal cortex of normal adult rats, and its levels were reduced if central NE levels were depleted by lesion of the locus ceruleus. The reduction of brain I kappa B alpha levels was paralleled by increased inflammatory responses to lipopolysaccharide. These results demonstrate that I kappa B alpha expression is regulated by NE at both transcriptional and post-transcriptional levels, which could contribute to the observed anti-inflammatory properties of NE in vitro and in vivo.
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Affiliation(s)
- Vitaliy Gavrilyuk
- Department of Anesthesiology, University of Illinois at Chicago, Chicago, Illinois 60612, USA
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Lin CS, Lue TF. Application of molecular biology to impotence research. MOLECULAR UROLOGY 2002; 5:91-8. [PMID: 11690555 DOI: 10.1089/10915360152559567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
To encourage further application of molecular biology in impotence research, we have compiled a list of techniques that have been or can be used in such endeavors. While by no means complete or perfect, the list encompasses both some of the most commonly used (such as RT-PCR) and some of the most promising (such as gene chip) methods. All three levels of the gene expression hierarchy, namely, DNA, RNA, and protein, are represented in the discussion. Whenever possible, each technique is discussed with references relevant to impotence research. Interested readers therefore can trace the original or the most recent research protocols for more detailed information.
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MESH Headings
- 3',5'-Cyclic-GMP Phosphodiesterases/genetics
- 3',5'-Cyclic-GMP Phosphodiesterases/metabolism
- Cyclic Nucleotide Phosphodiesterases, Type 5
- DNA Footprinting
- Electrophoresis, Gel, Two-Dimensional
- Erectile Dysfunction/physiopathology
- Humans
- Immunoblotting
- In Situ Hybridization
- Male
- Molecular Biology/methods
- Mutagenesis, Site-Directed
- Oligonucleotide Array Sequence Analysis
- Penis/physiology
- Polymerase Chain Reaction/methods
- Promoter Regions, Genetic
- RNA, Messenger/metabolism
- Single-Strand Specific DNA and RNA Endonucleases/metabolism
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
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