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Johnson I, Thurman AR, Cornell KA, Hatheway J, Dart C, Brainard CP, Friend DR, Goldstein A. Preliminary Efficacy of Topical Sildenafil Cream for the Treatment of Female Sexual Arousal Disorder: A Randomized Controlled Trial. Obstet Gynecol 2024; 144:144-152. [PMID: 38889431 PMCID: PMC11250102 DOI: 10.1097/aog.0000000000005648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 05/06/2024] [Accepted: 05/09/2024] [Indexed: 06/20/2024]
Abstract
OBJECTIVE To assess the efficacy of topical sildenafil cream, 3.6% among healthy premenopausal women with female sexual arousal disorder. METHODS We conducted a phase 2b, exploratory, randomized, placebo-controlled, double-blind study of sildenafil cream. Coprimary efficacy endpoints were the change from baseline to week 12 in the Arousal Sensation domain of the SFQ28 (Sexual Function Questionnaire) and question 14 of the FSDS-DAO (Female Sexual Distress Scale-Desire, Arousal, Orgasm). RESULTS Two hundred women with female sexual arousal disorder were randomized to sildenafil cream (n=101) or placebo cream (n=99). A total of 174 participants completed the study (sildenafil 90, placebo 84). Among the intention-to-treat (ITT) population, which included women with only female sexual arousal disorder and those with female sexual arousal disorder with concomitant sexual dysfunction diagnoses or genital pain, although the sildenafil cream group demonstrated greater improvement in the SFQ28 Arousal Sensation domain scores, there were no statistically significant differences between sildenafil and placebo cream users in the coprimary and secondary efficacy endpoints. An exploratory post hoc subset of the ITT population with an enrollment diagnosis of female sexual arousal disorder with or without concomitant decreased desire randomized to sildenafil cream reported significant increases in their SFQ28 Arousal Sensation domain score (least squares mean 2.03 [SE 0.62]) compared with placebo cream (least squares mean 0.08 [SE 0.71], P =.04). This subset achieved a larger mean improvement in the SFQ28 Desire and Orgasm domain scores. This subset population also had significantly reduced sexual distress and interpersonal difficulties with sildenafil cream use as measured by FSDS-DAO questions 3, 5, and 10 (all P ≤.04). CONCLUSION Topical sildenafil cream improved outcomes among women with female sexual arousal disorder, most significantly in those who did not have concomitant orgasmic dysfunction. In particular, in an exploratory analysis of a subset of women with female sexual arousal disorder with or without concomitant decreased desire, topical sildenafil cream increased sexual arousal sensation, desire, and orgasm and reduced sexual distress. CLINICAL TRIAL REGISTRATION ClinicalTrials.gov , NCT04948151.
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Affiliation(s)
- Isabella Johnson
- Daré Bioscience, San Diego, California; Strategic Science & Technologies, LLC, Cambridge, Massachusetts; Premier Research, Morrisville, North Carolina; and Copperstate OB/GYN, Tucson, Arizona
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Daniels SD, Boison D. Bipolar mania and epilepsy pathophysiology and treatment may converge in purine metabolism: A new perspective on available evidence. Neuropharmacology 2023; 241:109756. [PMID: 37820933 PMCID: PMC10841508 DOI: 10.1016/j.neuropharm.2023.109756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 09/25/2023] [Accepted: 10/07/2023] [Indexed: 10/13/2023]
Abstract
Decreased ATPergic signaling is an increasingly recognized pathophysiology in bipolar mania disease models. In parallel, adenosine deficit is increasingly recognized in epilepsy pathophysiology. Under-recognized ATP and/or adenosine-increasing mechanisms of several antimanic and antiseizure therapies including lithium, valproate, carbamazepine, and ECT suggest a fundamental pathogenic role of adenosine deficit in bipolar mania to match the established role of adenosine deficit in epilepsy. The depletion of adenosine-derivatives within the purine cycle is expected to result in a compensatory increase in oxopurines (uric acid precursors) and secondarily increased uric acid, observed in both bipolar mania and epilepsy. Cortisol-based inhibition of purine conversion to adenosine-derivatives may be reflected in observed uric acid increases and the well-established contribution of cortisol to both bipolar mania and epilepsy pathology. Cortisol-inhibited conversion from IMP to AMP as precursor of both ATP and adenosine may represent a mechanism for treatment resistance common in both bipolar mania and epilepsy. Anti-cortisol therapies may therefore augment other treatments both in bipolar mania and epilepsy. Evidence linking (i) adenosine deficit with a decreased need for sleep, (ii) IMP/cGMP excess with compulsive hypersexuality, and (iii) guanosine excess with grandiose delusions may converge to suggest a novel theory of bipolar mania as a condition characterized by disrupted purine metabolism. The potential for disease-modification and prevention related to adenosine-mediated epigenetic changes in epilepsy may be mirrored in mania. Evaluating the purinergic effects of existing agents and validating purine dysregulation may improve diagnosis and treatment in bipolar mania and epilepsy and provide specific targets for drug development.
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Affiliation(s)
- Scott D Daniels
- Hutchings Psychiatric Center, New York State Office of Mental Health, Syracuse, NY, 13210, USA
| | - Detlev Boison
- Dept. of Neurosurgery, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, 08854, USA.
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Woolf B, Rajasundaram S, Cronjé HT, Yarmolinsky J, Burgess S, Gill D. A drug target for erectile dysfunction to help improve fertility, sexual activity, and wellbeing: mendelian randomisation study. BMJ 2023; 383:e076197. [PMID: 38086555 PMCID: PMC10716676 DOI: 10.1136/bmj-2023-076197] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/09/2023] [Indexed: 12/18/2023]
Abstract
OBJECTIVE To investigate the association of genetically proxied (using a surrogate biomarker) inhibition of phosphodiesterase 5 (PDE5), an established drug target for erectile dysfunction, with fertility, sexual behaviour, and subjective wellbeing. DESIGN Two sample cis-mendelian randomisation study. SETTING Summary data on genetic associations obtained from the International Consortium for Blood Pressure and UK Biobank. PARTICIPANTS Individuals of European ancestry from the International Consortium for Blood Pressure (n=757 601) for estimating PDE5 inhibition (using the surrogate biomarker of diastolic blood pressure reduction), and UK Biobank (n=211 840) for estimating the fertility, sexual behaviour, and subjective wellbeing outcomes in male participants. INTERVENTION Genetically proxied PDE5 inhibition. MAIN OUTCOME MEASURES Number of children fathered, number of sexual partners, probability of never having had sexual intercourse, and subjective wellbeing. RESULTS Genetically proxied PDE5 inhibition was associated with male participants having 0.28 (95% confidence interval 0.16 to 0.39) more children (false discovery rate corrected P<0.001). This association was not identified in female participants. No evidence was found of an association between genetically proxied PDE5 inhibition and number of sexual partners, probability of never having had sexual intercourse, or self-reported wellbeing in male participants. CONCLUSIONS The findings of this study provide genetic support for PDE5 inhibition potentially increasing the number of children fathered by male individuals. Absence of this association in female participants supports increased propensity for sustained and robust penile erections as a potential underlying mechanism. Further studies are required to confirm this, however, and these findings should not promote indiscriminate use of PDE5 inhibitors, which can also have harmful adverse effects.
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Affiliation(s)
- Benjamin Woolf
- School of Psychological Science, University of Bristol, Bristol, BS8 1TU, UK
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, UK
- Medical Research Council Biostatistics Unit, University of Cambridge, Cambridge, UK
| | - Skanda Rajasundaram
- Centre for Evidence-Based Medicine, University of Oxford, Oxford, UK
- Faculty of Medicine, Imperial College London, London, UK
| | - Héléne T Cronjé
- Department of Public Health, Section of Epidemiology, University of Copenhagen, Copenhagen, Denmark
| | - James Yarmolinsky
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, UK
- Population Health Sciences, University of Bristol, Bristol, UK
| | - Stephen Burgess
- Medical Research Council Biostatistics Unit, University of Cambridge, Cambridge, UK
| | - Dipender Gill
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, UK
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4
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Domiati S, Abd El Galil K, Ragab H. Molecular Mechanics Simulations and Experimental Investigation of the Effect of Tadalafil on Various Inflammatory Pain Mediators. ACS OMEGA 2022; 7:43747-43758. [PMID: 36506154 PMCID: PMC9730770 DOI: 10.1021/acsomega.2c04761] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 11/09/2022] [Indexed: 06/17/2023]
Abstract
PURPOSE Tadalafil's exact analgesic mechanism is still unclear. The current study aimed to elucidate this mechanism in an inflammatory pain model. METHODS Computer-assisted simulation docking experiments were carried out to assess the binding of tadalafil to different ligands. The anti-inflammatory and analgesic effects of tadalafil were evaluated using formalin-induced paw edema and a von Frey filament test, respectively. The plantar paw of the mice was then dissected to quantify iNOS, nNOS, COX-2, TNFα, IL1, and IL10 gene expression levels using a real-time polymerase chain reaction. iNOS, TNFα, and COX-2 inhibition was reassessed in vitro using the ELISA technique. One-way analysis of variance followed by post hoc Tukey test or t-test was used to compare the means. RESULTS Docking analysis showed a superior binding score of tadalafil to COX-2, iNOS, IL-1, and TNF-α compared to that of indomethacin and morphine and a similar binding score to nNOS and IL-10 relative to that of indomethacin. In the in vivo study, tadalafil, after an hour of formalin administration, inhibited significantly paw edema, similar to indomethacin. Furthermore, it significantly increased the withdrawal force in the von Frey filament test as compared to the negative control, which was similar to the effect observed with indomethacin and morphine. The RT-PCR revealed that tadalafil reduced significantly the iNOS, COX-2, and TNF-α gene expressions but had no effect on nNOS, IL 1, and IL10. In vitro ELISA tests confirmed the inhibition of iNOS, COX-2, and TNF-α. CONCLUSION Tadalafil probably exerts its analgesic effect through the simultaneous inhibition of iNOS, COX-2, and TNF-α, which is not the case with other nonsteroidal anti-inflammatory drugs. Nevertheless, further studies are required to confirm its mechanism.
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Affiliation(s)
- Souraya Domiati
- Department
of Pharmacology and Therapeutics, Faculty of Pharmacy, Beirut Arab University, Beirut1107 2809, Lebanon
| | - Khaled Abd El Galil
- Department
of Pharmaceutical Sciences, Faculty of Pharmacy, Beirut Arab University, Beirut1107 2809, Lebanon
- Department
of Microbiology and Immunology, Faculty of Pharmacy, Mansoura University, Mansoura35516, Egypt
| | - Hanan Ragab
- Department
of Pharmaceutical Chemistry, Faculty of Pharmacy, Alexandria University, Alexandria21521, Egypt
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Leukes VN, Malherbe ST, Hiemstra A, Kotze LA, Roos K, Keyser A, De Swardt D, Gutschmidt A, Walzl G, du Plessis N. Sildenafil, a Type-5 Phosphodiesterase Inhibitor, Fails to Reverse Myeloid-Derived Suppressor Cell-Mediated T Cell Suppression in Cells Isolated From Tuberculosis Patients. Front Immunol 2022; 13:883886. [PMID: 35935981 PMCID: PMC9353143 DOI: 10.3389/fimmu.2022.883886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 06/24/2022] [Indexed: 11/13/2022] Open
Abstract
Successful TB treatment is hampered by increasing resistance to the two most effective first-line anti-TB drugs, namely isoniazid and rifampicin, thus innovative therapies focused on host processes, termed host-directed therapies (HDTs), are promising novel approaches for increasing treatment efficacy without inducing drug resistance. We assessed the ability of Sildenafil, a type-5 phosphodiesterase inhibitor, as a repurposed compound, to serve as HDT target, by counteracting the suppressive effects of myeloid-derived suppressor cells (MDSC) obtained from active TB cases on T-cell responsiveness. We confirm that MDSC suppress non-specific T-cell activation. We also show that Sildenafil treatment fails to reverse the MDSC-mediated suppression of T-cell functions measured here, namely activation and proliferation. The impact of Sildenafil treatment on improved immunity, using the concentration tested here, is likely to be minimal, but further identification and development of MDSC-targeting TB host-directed therapies are warranted.
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Affiliation(s)
- Vinzeigh N. Leukes
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Stephanus T. Malherbe
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Andriette Hiemstra
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Leigh A. Kotze
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Kelly Roos
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Alana Keyser
- Division of Medical Virology, Department of Pathology, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Dalene De Swardt
- Central Analytical Facility, Stellenbosch University, Cape Town, South Africa
| | - Andrea Gutschmidt
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Gerhard Walzl
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Nelita du Plessis
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
- *Correspondence: Nelita du Plessis,
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Megat S, Hugel S, Journée SH, Bohren Y, Lacaud A, Lelièvre V, Doridot S, Villa P, Bourguignon JJ, Salvat E, Schlichter R, Freund-Mercier MJ, Yalcin I, Barrot M. Antiallodynic action of phosphodiesterase inhibitors in a mouse model of peripheral nerve injury. Neuropharmacology 2021; 205:108909. [PMID: 34875284 DOI: 10.1016/j.neuropharm.2021.108909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 10/01/2021] [Accepted: 11/28/2021] [Indexed: 11/30/2022]
Abstract
Neuropathic pain arises as a consequence of a lesion or disease affecting the somatosensory nervous system. It is accompanied by neuronal and non-neuronal alterations, including alterations in intracellular second messenger pathways. Cellular levels of 3',5'-cyclic adenosine monophosphate (cAMP) and 3',5'-cyclic guanosine monophosphate (cGMP) are regulated by phosphodiesterase (PDE) enzymes. Here, we studied the impact of PDE inhibitors (PDEi) in a mouse model of peripheral nerve injury induced by placing a cuff around the main branch of the sciatic nerve. Mechanical hypersensitivity, evaluated using von Frey filaments, was relieved by sustained treatment with the non-selective PDEi theophylline and ibudilast (AV-411), with PDE4i rolipram, etazolate and YM-976, and with PDE5i sildenafil, zaprinast and MY-5445, but not by treatments with PDE1i vinpocetine, PDE2i EHNA or PDE3i milrinone. Using pharmacological and knock-out approaches, we show a preferential implication of delta opioid receptors in the action of the PDE4i rolipram and of both mu and delta opioid receptors in the action of the PDE5i sildenafil. Calcium imaging highlighted a preferential action of rolipram on dorsal root ganglia non-neuronal cells, through PDE4B and PDE4D inhibition. Rolipram had anti-neuroimmune action, as shown by its impact on levels of the pro-inflammatory cytokine tumor necrosis factor-α (TNFα) in the dorsal root ganglia of mice with peripheral nerve injury, as well as in human peripheral blood mononuclear cells (PBMCs) stimulated with lipopolysaccharides. This study suggests that PDEs, especially PDE4 and 5, may be targets of interest in the treatment of neuropathic pain.
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Affiliation(s)
- Salim Megat
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Sylvain Hugel
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Sarah H Journée
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Yohann Bohren
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France; Hôpitaux Universitaires de Strasbourg, Centre d'Evaluation et de Traitement de la Douleur, Strasbourg, France
| | - Adrien Lacaud
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Vincent Lelièvre
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Stéphane Doridot
- Centre National de la Recherche Scientifique, Université de Strasbourg, Chronobiotron, Strasbourg, France
| | - Pascal Villa
- Université de Strasbourg, Centre National de la Recherche Scientifique, Plateforme de Chimie Biologique Intégrative de Strasbourg, UAR3286, Illkirch, France
| | - Jean-Jacques Bourguignon
- Université de Strasbourg, Centre National de la Recherche Scientifique, Laboratoire d'Innovation Thérapeutique, Illkirch, France
| | - Eric Salvat
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France; Hôpitaux Universitaires de Strasbourg, Centre d'Evaluation et de Traitement de la Douleur, Strasbourg, France
| | - Remy Schlichter
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Marie-José Freund-Mercier
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Ipek Yalcin
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France.
| | - Michel Barrot
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France.
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Mintzes B, Tiefer L, Cosgrove L. Bremelanotide and flibanserin for low sexual desire in women: the fallacy of regulatory precedent. Drug Ther Bull 2021; 59:185-188. [PMID: 34642243 DOI: 10.1136/dtb.2021.000020] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The US Food and Drug Administration (FDA) has approved two drugs for 'hypoactive sexual desire disorder' in women, flibanserin (Addyi) in 2015 and bremelanotide (Vyleesi) in 2019. In this paper we examine the outcome measures and clinical trial data upon which regulatory approval was based. In clinical trials, flibanserin led to an average of only one additional enjoyable sexual experience every two months, bremelanotide to none. Trials for both drugs feature shifts in primary outcomes and a contested indication. A politicised industry-sponsored advocacy campaign and conflicted patient and expert testimony likely influenced flibanserin's approval at its third attempt. Bremelanotide, with even weaker efficacy, capitalised on the regulatory precedent set by the approval of flibanserin. Reconsideration of regulatory decisions to approve these drugs is in order, as well as a broader examination of how future regulatory decisions can better address conflicts of interest and clinically meaningful benefit.
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Affiliation(s)
- Barbara Mintzes
- School of Pharmacy and Charles Perkins Centre, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia .,School of Population and Public Health, University of British Columbia, Vancouver, British Columbia, Canada
| | - Leonore Tiefer
- Department of Psychiatry, New York School of Medicine, New York, New York, USA
| | - Lisa Cosgrove
- Counseling Psychology Department and Applied Ethics Center, University of Massachusetts Boston, Boston, Massachusetts, USA
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8
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Leukes V, Walzl G, du Plessis N. Myeloid-Derived Suppressor Cells as Target of Phosphodiesterase-5 Inhibitors in Host-Directed Therapeutics for Tuberculosis. Front Immunol 2020; 11:451. [PMID: 32269568 PMCID: PMC7109258 DOI: 10.3389/fimmu.2020.00451] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 02/27/2020] [Indexed: 01/11/2023] Open
Abstract
Resistance toward current and new classes of anti-tuberculosis (anti-TB) antibiotics are rapidly emerging; thus, innovative therapies focused on host processes, termed host-directed therapies (HDTs), are promising novel approaches for shortening therapy regimens without inducing drug resistance. Development of new TB drugs is lengthy and expensive, and success is not guaranteed; thus, alternatives are needed. Repurposed drugs have already passed Food and Drug Administration (FDA) as well as European Medicines Agency (EMA) safety requirements and may only need to prove efficacy against Mycobacterium tuberculosis (M.tb). Phosphodiesterases (PDEs) hydrolyze the catalytic breakdown of both cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) to their inactive mononucleotides. Advances in molecular pharmacology have identified 11 PDE families; and the success of sildenafil, a PDE-5 selective inhibitor (PDE-5i), in treating pulmonary hypertension and erectile dysfunction has invigorated research into the therapeutic potential of selective PDE inhibitors in other conditions. Myeloid-derived suppressor cells (MDSCs) suppress anti-TB T-cell responses, likely contributing to TB disease progression. PDE-5i increases cGMP within MDSC resulting in the downregulation of arginase-1 (ARG1) and nitric oxide synthase 2 (NOS2), reducing MDSC's suppressive potential. The effect of this reduction decreases MDSC-induced T-cell-suppressive mechanisms. This review highlights the possibility of HDT targeting of MDSC, using a PDE-5i in combination with the current TB regimen, resulting in improved TB treatment efficacy.
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Affiliation(s)
- Vinzeigh Leukes
- Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, DST-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Stellenbosch University, Cape Town, South Africa
| | - Gerhard Walzl
- Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, DST-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Stellenbosch University, Cape Town, South Africa
| | - Nelita du Plessis
- Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, DST-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Stellenbosch University, Cape Town, South Africa
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Teplitsky S, Murphy A, Shenot PJ. Knowledge Gaps in Urologic Care of Female Spinal Cord Injury Patients. Curr Urol Rep 2019; 20:21. [PMID: 30904966 DOI: 10.1007/s11934-019-0884-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
PURPOSE OF REVIEW We highlight the substantial gaps in knowledge on urologic care of female spinal cord injury (SCI) patients. RECENT FINDINGS Males account for approximately 80% of people living with SCI in developed nations. Although there is a robust body of literature in some aspects of urologic care of individuals with SCI, such as treatments for neurogenic detrusor overactivity, there are relatively few studies focusing specifically on females. There are also few studies focusing on other aspects of urologic care of women with SCI such as sexual dysfunction, pelvic organ prolapse, and bladder cancer. Established guidelines for bladder management exist, generally recommending intermittent catheterization, but the fact remains that a substantial number of women with SCI utilize indwelling catheters for bladder management. There remains a paucity of literature using patient-reported measures regarding both outcomes and experiences of urologic management in the SCI population. Bladder management is challenging for many women with SCI. There are few studies on other urologic concerns in women with SCI.
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Affiliation(s)
- Seth Teplitsky
- Department of Urology, Sidney Kimmel Medical College, Thomas Jefferson University, 1025 Walnut St, Ste 1100, Philadelphia, PA, 19107, USA
| | - Alana Murphy
- Department of Urology, Sidney Kimmel Medical College, Thomas Jefferson University, 1025 Walnut St, Ste 1100, Philadelphia, PA, 19107, USA
| | - Patrick J Shenot
- Department of Urology, Sidney Kimmel Medical College, Thomas Jefferson University, 1025 Walnut St, Ste 1100, Philadelphia, PA, 19107, USA.
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10
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Caruso S, Cianci A, Cianci S, Monaco C, Fava V, Cavallari V. Ultrastructural Study of Clitoral Cavernous Tissue and Clitoral Blood Flow From Type 1 Diabetic Premenopausal Women on Phosphodiesterase-5 Inhibitor. J Sex Med 2019; 16:375-382. [PMID: 30773497 DOI: 10.1016/j.jsxm.2019.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 12/29/2018] [Accepted: 01/04/2019] [Indexed: 01/21/2023]
Abstract
BACKGROUND The effects of phosphodiesterase-type 5 (PDE5) inhibitors on the in vivo clitoral structure of women with diabetes have never been investigated. AIM To study the in vivo structural and hemodynamic changes of the clitoris in premenopausal women with type 1 diabetes on PDE5 inhibitors. METHODS 38 premenopausal women with type 1 diabetes aged 36 -46 years. A randomized 1:1 study design was used: Study Group (group A) on Tadalafil 5 mg daily, and control group (group B). Blood samples were taken from each woman to measure HbA1c, testosterone, and Free Androgen Index. The women underwent microbiopsy of the clitoral body by means of semiautomatic gun during total anesthesia for surgery therapy of a benign gynecological pathology. The tissue removed was processed for electron microscopy. Translabial color Doppler ultrasound was used to measure the peak systolic velocity (PSV), the end diastolic velocity (EDV), and the pulsatility index (PI) of clitoral arteries. MAIN OUTCOME MEASURES Micro-ultrastructure observation of clitoral tissue and color Doppler sonography of clitoral blood flow. RESULTS Of the 38 women, 13 (68.4%) of group A and 15 (78.9%) of group B completed the study. Group A showed a mean PSV and EDV increase, and a mean PI decrease with respect to baseline (P < .001). Group B did not show any change in both the parameters (P = NS). By a quantitative study in both groups a variable degree of ultrastructural abnormalities of smooth muscle cells (SMCs) was observed, consisting in increased glycogen and lipoic deposits, cytoplasmic vacuoles, and focal increase of electron density of SMCs. Moreover, the mean SMC thickness of group A (1.83 ± 0.68 µm) was larger than that of group B (1.3 ± 0.41 µm) (P = .02). CLINICAL IMPLICATIONS PDE5 inhibitors could be used to treat diabetic women with genital arousal disorder. STRENGTHS & LIMITATIONS The study shows a clear effect of PDE5 inhibitors on clitoral SMCs. However, a limit was to not have investigated the sexual function/behavior of women of both groups, this was because of the short time of the study. CONCLUSION This study could help to understand in what way PDE5 inhibitors act on the ultrastructural pathophysiological clitoral cavernous tissue of women with diabetes. It could support PDE5 inhibitor usage in women with genital sexual arousal disorder due to metabolic diseases. Caruso S, Cianci A, Cianci S, et al. Ultrastructural Study of Clitoral Cavernous Tissue and Clitoral Blood Flow From Type 1 Diabetic Premenopausal Women on Phosphodiesterase-5 Inhibitor. J Sex Med 2019;16:375-382.
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Affiliation(s)
- Salvatore Caruso
- Department of General Surgery and Medical Surgical Specialties, Gynecological Clinic, Research Group for Sexology, University of Catania, Catania, Italy.
| | - Antonio Cianci
- Department of General Surgery and Medical Surgical Specialties, Gynecological Clinic, Research Group for Sexology, University of Catania, Catania, Italy
| | - Stefano Cianci
- Department of General Surgery and Medical Surgical Specialties, Gynecological Clinic, Research Group for Sexology, University of Catania, Catania, Italy
| | - Caterina Monaco
- Department of General Surgery and Medical Surgical Specialties, Gynecological Clinic, Research Group for Sexology, University of Catania, Catania, Italy
| | - Valentina Fava
- Department of General Surgery and Medical Surgical Specialties, Gynecological Clinic, Research Group for Sexology, University of Catania, Catania, Italy
| | - Vittorio Cavallari
- Unit of Ultrastructural Pathology, Department of Human Pathology, University of Messina, Messina, Italy
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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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12
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Courtois F, Alexander M, McLain AB(J. Women's Sexual Health and Reproductive Function After SCI. Top Spinal Cord Inj Rehabil 2017; 23:20-30. [PMID: 29339874 PMCID: PMC5340506 DOI: 10.1310/sci2301-20] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Sexual function and to a lesser extent reproduction are often disrupted in women with spinal cord injuries (SCI), who must be educated to better understand their sexual and reproductive health. Women with SCI are sexually active; they can use psychogenic or reflexogenic stimulation to obtain sexual pleasure and orgasm. Treatment should consider a holistic approach using autonomic standards to describe remaining sexual function and to assess both genital function and psychosocial factors. Assessment of genital function should include thoracolumbar dermatomes, vulvar sensitivity (touch, pressure, vibration), and sacral reflexes. Self-exploration should include not only clitoral stimulation, but also stimulation of the vagina (G spot), cervix, and nipples conveyed by different innervation sources. Treatments may consider PDE5 inhibitors and flibanserin on an individual basis, and secondary consequences of SCI should address concerns with spasticity, pain, incontinence, and side effects of medications. Psychosocial issues must be addressed as possible contributors to sexual dysfunctions (eg, lower self-esteem, past sexual history, depression, dating habits). Pregnancy is possible for women with SCI; younger age at the time of injury and at the time of pregnancy being significant predictors of successful pregnancy, along with marital status, motor score, mobility, and occupational scores. Pregnancy may decrease the level of functioning (eg, self-care, ambulation, upper-extremity tasks), may involve complications (eg, decubitus ulcers, weight gain, urological complications), and must be monitored for postural hypotension and autonomic dysreflexia. Taking into consideration the physical and psychosocial determinants of sexuality and childbearing allows women with SCI to achieve positive sexual and reproductive health.
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Affiliation(s)
- Frédérique Courtois
- Departement of Sexology, Université du Québec à Montréal, Montreal, Canada
- Institut de réadaptation Gingras Lindsay de Montréal, Montreal, Canada
| | - Marcalee Alexander
- Department of Rehabilitative Medicine, Birmingham VA Medical Center, Birmingham, Alabama
- Department of Physical Medicine and Rehabilitation, University of Alabama at Birmingham
- Department of Physical Medicine and Rehabilitation, Harvard School of Medicine, Boston, Massachusetts
| | - Amie B. (Jackson) McLain
- Department of Physical Medicine and Rehabilitation, University of Alabama School of Medicine, Birmingham, Alabama
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13
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Gao L, Yang L, Qian S, Li T, Han P, Yuan J. Systematic review and meta-analysis of phosphodiesterase type 5 inhibitors for the treatment of female sexual dysfunction. Int J Gynaecol Obstet 2015; 133:139-45. [DOI: 10.1016/j.ijgo.2015.08.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Revised: 08/14/2015] [Accepted: 12/01/2015] [Indexed: 12/29/2022]
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Morrow KA, Seifert R, Kaever V, Britain AL, Sayner SL, Ochoa CD, Cioffi EA, Frank DW, Rich TC, Stevens T. Heterogeneity of pulmonary endothelial cyclic nucleotide response to Pseudomonas aeruginosa ExoY infection. Am J Physiol Lung Cell Mol Physiol 2015; 309:L1199-207. [PMID: 26386118 PMCID: PMC4652153 DOI: 10.1152/ajplung.00165.2015] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 09/11/2015] [Indexed: 01/16/2023] Open
Abstract
Here, we tested the hypothesis that a promiscuous bacterial cyclase synthesizes purine and pyrimidine cyclic nucleotides in the pulmonary endothelium. To test this hypothesis, pulmonary endothelial cells were infected with a strain of the Gram-negative bacterium Pseudomonas aeruginosa that introduces only exoenzyme Y (PA103 ΔexoUexoT::Tc pUCPexoY; ExoY(+)) via a type III secretion system. Purine and pyrimidine cyclic nucleotides were simultaneously detected using mass spectrometry. Pulmonary artery (PAECs) and pulmonary microvascular (PMVECs) endothelial cells both possess basal levels of four different cyclic nucleotides in the following rank order: cAMP > cUMP ≈ cGMP ≈ cCMP. Endothelial gap formation was induced in a time-dependent manner following ExoY(+) intoxication. In PAECs, intercellular gaps formed within 2 h and progressively increased in size up to 6 h, when the experiment was terminated. cGMP concentrations increased within 1 h postinfection, whereas cAMP and cUMP concentrations increased within 3 h, and cCMP concentrations increased within 4 h postinfection. In PMVECs, intercellular gaps did not form until 4 h postinfection. Only cGMP and cUMP concentrations increased at 3 and 6 h postinfection, respectively. PAECs generated higher cyclic nucleotide levels than PMVECs, and the cyclic nucleotide levels increased earlier in response to ExoY(+) intoxication. Heterogeneity of the cyclic nucleotide signature in response to P. aeruginosa infection exists between PAECs and PMVECs, suggesting the intracellular milieu in PAECs is more conducive to cNMP generation.
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Affiliation(s)
- K A Morrow
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, Alabama; Center for Lung Biology, University of South Alabama, Mobile, Alabama
| | - R Seifert
- Institute of Pharmacology, Hannover Medical School, Hannover, Germany
| | - V Kaever
- Research Core Unit Metabolomics, Hannover Medical School, Hannover, Germany
| | - A L Britain
- Department of Pharmacology, University of South Alabama, Mobile, Alabama; Center for Lung Biology, University of South Alabama, Mobile, Alabama
| | - S L Sayner
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, Alabama; Center for Lung Biology, University of South Alabama, Mobile, Alabama
| | - C D Ochoa
- Physician-Scientist Training Program, Department of Medicine, University of Texas-Southwestern Medical Center, Dallas, Texas; Physician-Scientist Training Program, Division of Pulmonary and Critical Care, University of Texas-Southwestern Medical Center, Dallas, Texas
| | - E A Cioffi
- Department of Pharmacology, University of South Alabama, Mobile, Alabama; Center for Lung Biology, University of South Alabama, Mobile, Alabama
| | - D W Frank
- Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin; and Center for Infectious Disease Research, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - T C Rich
- Department of Pharmacology, University of South Alabama, Mobile, Alabama; Center for Lung Biology, University of South Alabama, Mobile, Alabama
| | - T Stevens
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, Alabama; Department of Medicine, University of South Alabama, Mobile, Alabama; Center for Lung Biology, University of South Alabama, Mobile, Alabama;
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15
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Courtois F, Charvier K. Sexual dysfunction in patients with spinal cord lesions. HANDBOOK OF CLINICAL NEUROLOGY 2015; 130:225-45. [PMID: 26003247 DOI: 10.1016/b978-0-444-63247-0.00013-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Many aspects of sexuality can be disrupted following a spinal cord lesion (SCL). It can alter an individual's self-esteem and body image, interfere with positioning and mobility, introduce unexpected problems with incontinence and spasticity, decrease pleasure, and delay orgasm. Sexual concerns in men can involve erectile function, essential for intercourse, ejaculation function, necessary for fertility, and the ability to reach orgasm. In women they can involve concerns with vaginal lubrication, genital congestion, and vaginal infections, which can all go unnoticed, and orgasm, which may be lost. All of these concerns must be addressed during rehabilitation as individuals with SCL continue to live an active sexual life, and consider sexuality among their top priority for quality of life. This chapter describes the impact of SCL on various phases of men's and women's sexual responses and on various aspects of sexuality. Treatments are described in terms of what is currently available and what is specific to the SCL population. New approaches in particular for women are described, along with tips from sexual counseling which consider an overall approach, taking into account the primary, secondary, and tertiary consequences of the SCL on the individual's sexuality. Throughout the chapter, attempts are made to integrate neurophysiologic knowledge, findings from the literature on SCL, and clinical experience in sexual rehabilitation.
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Affiliation(s)
- Frédérique Courtois
- Department of Sexology, Université du Québec à Montréal, Montreal, Quebec, Canada.
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Caruso S, Cicero C, Romano M, Lo Presti L, Ventura B, Malandrino C. Tadalafil 5 mg Daily Treatment for Type 1 Diabetic Premenopausal Women Affected by Sexual Genital Arousal Disorder. J Sex Med 2012; 9:2057-65. [DOI: 10.1111/j.1743-6109.2012.02777.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Vascular alterations and sexual function in systemic sclerosis. Int J Rheumatol 2010; 2010:139020. [PMID: 20981305 PMCID: PMC2958492 DOI: 10.1155/2010/139020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2010] [Accepted: 07/08/2010] [Indexed: 11/17/2022] Open
Abstract
Sexual dysfunction is common in systemic sclerosis (SSc). Male erectile dysfunction (MED) has been reported in around 80% of subjects and more than half of female patients fulfill criteria for diagnosis as female sexual arousal Disorder (FSAD). While some evidence supports a role for cavernosal fibrosis, abundant data suggest that MED is yet another clinical feature of SSc related to vasculopathy. The contribution of vasculopathy to the more complex issues of female sexual dysfunction is less clear. Inhibitors of Type V phosphodiesterase are effective in men with MED secondary to SSc. Limited study in women suggests inconsistent effects on behavior (frequency) but not on measures related to perfusion. Sexual activity is an important component of quality of life and an important domain for the caregiver to address; it is not clear that it warrants primary consideration as a consistent measure of scleroderma-related vasculopathy.
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Courtois F, Charvier K, Leriche A, Côté M, Lemieux A. L’évaluation et le traitement des troubles des réactions sexuelles chez l’homme et la femme blessés médullaires. SEXOLOGIES 2009. [DOI: 10.1016/j.sexol.2007.11.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Affiliation(s)
- Clair Kaplan
- Yale University School of Nursing, New Haven, Conn, USA
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Beharry RKS, Hale TM, Heaton JPW, Shamloul R, Adams MA. Restoration of female genital vasocongestive arousal responses in young and aged rats. J Sex Med 2008; 5:804-812. [PMID: 18221278 DOI: 10.1111/j.1743-6109.2007.00750.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Treatments of aged, male hypertensive rats that induce vascular remodeling or that normalize endothelial function are known to produce sustained improvements in erectile function. Whether the treatments targeting these processes benefit female genital vasocongestive arousal (GVA) responses is currently not known. AIM To determine whether the actions of nitric oxide (NO) are critical to the apomorphine (APO)-generated GVA responses in both intact and ovariectomized OVX young adult female rats (before any aging-associated decreases in the responses). In addition, we also investigated whether the diminished GVA responses in aged rats could be restored, at least in part, using an antihypertensive treatment, which is known to enhance erectile responses and improve general vascular function in male rats. METHODS In female Wistar rats, APO-induced GVA responses (80 microg/kg, subcutaneously [sc], 30 minutes) were assessed by videomonitoring following various treatments. Young adult females were ovariectomized or were treated with the nitric oxide synthase (NOS) inhibitor N-nitro-L-arginine methyl ester (30 mg/kg, iv), followed by an NO mimetic, sodium nitroprusside (10 microg/kg/minute, intravenous). Aged females (18 months) were treated for 2 weeks with the angiotensin converting enzyme (ACE) inhibitor, enalapril (30 mg/kg/day, orally) plus low sodium (0.04%). MAIN OUTCOME MEASURES APO-induced GVA responses in female rats. RESULTS There was an age-associated reduction in sexual responses in normotensive rats that was greatly enhanced (fourfold) by brief, aggressive antihypertensive treatment. The enhanced vasocongestive responses persisted for a 5-week off-treatment. Both OVX and NOS inhibition significantly decreased sexual responses by approximately 80% in young female rats. Systemic administration of an NO mimetic recovered vasocongestive responses in the NOS-blocked rats, but not in OVX animals. CONCLUSIONS Although mechanisms were not established, the major findings were that brief aggressive ACE inhibitor treatment markedly improved sexual responses in aged female rats, and systemic delivery of an NO mimetic recovered sexual responses in globally NOS-blocked animals.
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Affiliation(s)
- Rochard K S Beharry
- Queen's University-Department of Pharmacology and Toxicology, Kingston, Ontario, Canada
| | - Taben M Hale
- University of Montreal- Department of Pharmacology, Montreal, Quebec, Canada
| | - Jeremy P W Heaton
- Queen's University-Department of Pharmacology and Toxicology, Kingston, Ontario, Canada
| | - Rany Shamloul
- Queen's University-Department of Pharmacology and Toxicology, Kingston, Ontario, Canada;; Department of Andrology, Sexology and STDs, Cairo University, Cairo, Egypt
| | - Michael A Adams
- Queen's University-Department of Pharmacology and Toxicology, Kingston, Ontario, Canada;.
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21
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Miyagawa Y. Feasibility of sildenafil citrate for female sexual dysfunction (Editorial Comment). Int J Urol 2007. [DOI: 10.1111/j.1442-2042.2007.01519.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Werkström V, Svensson A, Andersson KE, Hedlund P. Phosphodiesterase 5 in the female pig and human urethra: morphological and functional aspects. BJU Int 2006; 98:414-23. [PMID: 16626307 DOI: 10.1111/j.1464-410x.2006.06217.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVE To characterize the distribution of phosphodiesterase 5 (PDE-5), cGMP and cGMP-dependent protein kinase I (PKG1), and to evaluate the effect of pharmacological inhibition of PDE-5 in isolated preparations of pig and human urethra, as the nitric oxide (NO)/cGMP pathway generates the main inhibitory signals to reduce resistance in the bladder outlet and urethra during emptying of the bladder. MATERIALS AND METHODS After obtaining ethics committee approval, urethral specimens were obtained from three female patients during cystectomy, and from young female pigs. The specimens were prepared for immunohistochemical investigations and for functional studies in organ baths. Effects of sildenafil, vardenafil and tadalafil (1 nm to 30 microm) were studied in l-noradrenaline (1 microm)-activated or spontaneously contracted preparations, and on relaxations induced by electrical-field stimulation (EFS). Levels of cGMP were determined by radioimmunoassay. RESULTS After stimulation with the NO donor, DETA NONO-ate (1 mm), there was greater cGMP-immunoreactivity (IR) in urethral and vascular smooth muscles. There was a wide distribution of cGMP- and vimentin-positive interstitial cells between pig urethral smooth muscle bundles. There was also cGMP-IR within NO-synthase-IR endothelium. There was PDE-5 IR within the urethral and vascular smooth muscle cells, but also in vascular endothelial cells that expressed cGMP-IR. In pig and human sections, there was strong PKG1-IR in alpha-actin-IR urethral smooth muscle cells that also contained IR for cGMP. Sildenafil, vardenafil and tadalafil caused mean (sem) concentration-dependent relaxations of the pig urethra which, at 30 microm, were 80 (3)% (11 samples), 81 (5)% (12 samples) and 64 (4)% (10 samples) of the spontaneous tone. The relaxation of L-noradrenaline-contracted female human urethra was 100% in response to 10 microm sildenafil, and 85 (15)% and 47 (13)% for 30 microm of vardenafil and tadalafil, respectively (three samples). Vardenafil or sildenafil (30 microm) doubled cGMP levels in pig specimens. There were no effects on cGMP levels with tadalafil. EFS (1-32 Hz) caused l-NG-nitroarginine-sensitive relaxations of pig urethral muscle that were increased in amplitude and duration by PDE-5 inhibition. At 0.1 microm, sildenafil, vardenafil or tadalafil significantly prolonged the mean (sem) duration of the relaxation at 4 Hz by 55 (19)%, 45 (14)% and 51 (12)%, respectively. CONCLUSIONS PDE-5-, cGMP- and PKG1-IR is widely distributed in human and pig urethral tissues. Nerve-induced relaxations of urethral preparations were enhanced at low concentrations of sildenafil, vardenafil and tadalafil, whereas there were direct smooth muscle-relaxant actions of the PDE-5 inhibitors at high concentrations. Inhibition of PDE-5 might be an interesting option to facilitate cGMP-mediated relaxation of the outflow region.
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Affiliation(s)
- Viktoria Werkström
- Department of Clinical and Experimental Pharmacology, Institute for Laboratory Medicine, Lund University Hospital, Lund, Sweden
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