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AlRuwaili R, Al-Kuraishy HM, Alruwaili M, Khalifa AK, Alexiou A, Papadakis M, Saad HM, Batiha GES. The potential therapeutic effect of phosphodiesterase 5 inhibitors in the acute ischemic stroke (AIS). Mol Cell Biochem 2024; 479:1267-1278. [PMID: 37395897 PMCID: PMC11116240 DOI: 10.1007/s11010-023-04793-1] [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: 05/10/2023] [Accepted: 06/16/2023] [Indexed: 07/04/2023]
Abstract
Acute ischemic stroke (AIS) is a focal neurological disorder that accounts for 85% of all stroke types, due to occlusion of cerebral arteries by thrombosis and emboli. AIS is also developed due to cerebral hemodynamic abnormality. AIS is associated with the development of neuroinflammation which increases the severity of AIS. Phosphodiesterase enzyme (PDEs) inhibitors have neuro-restorative and neuroprotective effects against the development of AIS through modulation of the cerebral cyclic adenosine monophosphate (cAMP)/cyclic guanosine monophosphate (cGMP)/nitric oxide (NO) pathway. PDE5 inhibitors through mitigation of neuroinflammation may decrease the risk of long-term AIS-induced complications. PDE5 inhibitors may affect the hemodynamic properties and coagulation pathway which are associated with thrombotic complications in AIS. PDE5 inhibitors reduce activation of the pro-coagulant pathway and improve the microcirculatory level in patients with hemodynamic disturbances in AIS. PDE5 inhibitors mainly tadalafil and sildenafil improve clinical outcomes in AIS patients through the regulation of cerebral perfusion and cerebral blood flow (CBF). PDE5 inhibitors reduced thrombomodulin, P-selectin, and tissue plasminogen activator. Herein, PDE5 inhibitors may reduce activation of the pro-coagulant pathway and improve the microcirculatory level in patients with hemodynamic disturbances in AIS. In conclusion, PDE5 inhibitors may have potential roles in the management of AIS through modulation of CBF, cAMP/cGMP/NO pathway, neuroinflammation, and inflammatory signaling pathways. Preclinical and clinical studies are recommended in this regard.
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Affiliation(s)
- Raed AlRuwaili
- Department of Internal Medicine, College of Medicine, Jouf University, Sakaka, Saudi Arabia
| | - Hayder M Al-Kuraishy
- Department of Clinical Pharmacology and Medicine, College of Medicine, ALmustansiriyia University, Baghdad, Iraq
| | - Mubarak Alruwaili
- Department of Internal Medicine, College of Medicine, Jouf University, Sakaka, Saudi Arabia
| | - Amira Karam Khalifa
- Department of Medical Pharmacology, Kasr El-Ainy School of Medicine, Cairo University, El Manial, Cairo, 11562, Egypt
- Lecturer of Medical Pharmacology, Nahda Faculty of Medicine, Beni Suef, Egypt
| | - Athanasios Alexiou
- Department of Science and Engineering, Novel Global Community Educational Foundation, Hebersham, NSW, 2770, Australia
- AFNP Med, 1030, Vienna, Austria
| | - Marios Papadakis
- Department of Surgery II, University Hospital Witten-Herdecke, University of Witten-Herdecke, Heusnerstrasse 40, 42283, Wuppertal, Germany.
| | - Hebatallah M Saad
- Department of Pathology, Faculty of Veterinary Medicine, Matrouh University, Marsa Matrouh, 51744, Egypt
| | - Gaber El-Saber Batiha
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, Damanhour, 22511, AlBeheira, Egypt
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2
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ElHady AK, El-Gamil DS, Abdel-Halim M, Abadi AH. Advancements in Phosphodiesterase 5 Inhibitors: Unveiling Present and Future Perspectives. Pharmaceuticals (Basel) 2023; 16:1266. [PMID: 37765073 PMCID: PMC10536424 DOI: 10.3390/ph16091266] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 08/25/2023] [Accepted: 09/05/2023] [Indexed: 09/29/2023] Open
Abstract
Phosphodiesterase 5 (PDE5) inhibitors presented themselves as important players in the nitric oxide/cGMP pathway, thus exerting a profound impact on various physiological and pathological processes. Beyond their well-known efficacy in treating male erectile dysfunction (ED) and pulmonary arterial hypertension (PAH), a plethora of studies have unveiled their significance in the treatment of a myriad of other diseases, including cognitive functions, heart failure, multiple drug resistance in cancer therapy, immune diseases, systemic sclerosis and others. This comprehensive review aims to provide an updated assessment of the crucial role played by PDE5 inhibitors (PDE5-Is) as disease-modifying agents taking their limiting side effects into consideration. From a medicinal chemistry and drug discovery perspective, the published PDE5-Is over the last 10 years and their binding characteristics are systemically discussed, and advancement in properties is exposed. A persistent challenge encountered with these agents lies in their limited isozyme selectivity; considering this obstacle, this review also highlights the breakthrough development of the recently reported PDE5 allosteric inhibitors, which exhibit an unparalleled level of selectivity that was rarely achievable by competitive inhibitors. The implications and potential impact of these novel allosteric inhibitors are meticulously explored. Additionally, the concept of multi-targeted ligands is critically evaluated in relation to PDE5-Is by inspecting the broader spectrum of their molecular interactions and effects. The objective of this review is to provide insight into the design of potent, selective PDE5-Is and an overview of their biological function, limitations, challenges, therapeutic potentials, undergoing clinical trials, future prospects and emerging uses, thus guiding upcoming endeavors in both academia and industry within this domain.
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Affiliation(s)
- Ahmed K. ElHady
- School of Life and Medical Sciences, University of Hertfordshire Hosted by Global Academic Foundation, New Administrative Capital, Cairo 11865, Egypt;
| | - Dalia S. El-Gamil
- Department of Chemistry, Faculty of Pharmacy, Ahram Canadian University, Cairo 12451, Egypt;
| | - Mohammad Abdel-Halim
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy and Biotechnology, German University in Cairo, Cairo 11835, Egypt;
| | - Ashraf H. Abadi
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy and Biotechnology, German University in Cairo, Cairo 11835, Egypt;
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3
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Kloner RA, Stanek E, Crowe CL, Singhal M, Pepe RS, Bradsher J, Rosen RC. Effect of phosphodiesterase type 5 inhibitors on major adverse cardiovascular events and overall mortality in a large nationwide cohort of men with erectile dysfunction and cardiovascular risk factors: A retrospective, observational study based on healthcare claims and national death index data. J Sex Med 2023; 20:38-48. [PMID: 36897243 DOI: 10.1093/jsxmed/qdac005] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 08/23/2022] [Accepted: 09/12/2022] [Indexed: 01/15/2023]
Abstract
BACKGROUND Treatment with phosphodiesterase type 5 inhibitors (PDE-5is) is effective in treating erectile dysfunction (ED). AIM The objective of this study was to determine the effect of PDE-5is on the incidence of major adverse cardiovascular (CV) events (MACE; composite outcome of CV death, hospitalization for myocardial infarction, coronary revascularization, stroke, heart failure, and unstable angina pectoris) and overall mortality. METHODS A retrospective observational cohort study was conducted in a large US claims database in men with ≥1 diagnosis of ED without prior MACE within 1 year, from January 1, 2006, to October 31, 2020. The exposed group had ≥1 claim for PDE-5i and the unexposed group had no claims for PDE-5i, and the groups were matched up to 1:4 on baseline risk variables. OUTCOME The primary outcome was MACE and the secondary outcomes were overall mortality and individual components of MACE, determined by multivariable Cox proportional hazard modeling. RESULTS Matched plus multivariable analyses showed that MACE was lower by 13% in men exposed (n = 23 816) to PDE-5is (hazard ratio [HR] 0.87; 95% CI 0.79-0.95; P = .001) vs nonexposure (n = 48 682) over mean follow-up periods of 37 and 29 months, respectively, with lower incidence of coronary revascularization (HR 0.85; 95% CI 0.73-0.98; P = .029), heart failure (HR 0.83; 95% CI 0.72-0.97; P = .016), unstable angina (HR 0.78; 95% CI 0.64-0.96; P = .021), and CV death (HR 0.61; 95% CI 0.41-0.90; P = .014) with PDE-5i exposure. Phosphodiesterase type 5 inhibitor-exposed men had a 25% lower incidence of overall mortality (HR 0.75; 95% CI 0.65-0.87; P < .001). Men without coronary artery disease (CAD) but with CV risk factors at baseline showed a similar pattern. In the main study cohort, men in the highest quartile of PDE-5i exposure had the lowest incidence of MACE (HR 0.45; 95% CI 0.37-0.54; P < .001) and overall mortality (HR 0.51; 95% CI 0.37-0.71; P < .001) vs the lowest exposure quartile. In a subgroup with baseline type 2 diabetes (n = 6503), PDE-5i exposure was associated with a lower MACE risk (HR 0.79; 95% CI 0.64-0.97; P = .022). CLINICAL IMPLICATIONS PDE-5is may have cardioprotective effects. STRENGTHS AND LIMITATIONS Strengths are the large numbers of participants and consistency of the data; limitations include the retrospective nature of the study and unknown confounders. CONCLUSIONS In a large population of US men with ED, PDE-5i exposure was associated with lower incidence of MACE, CV death, and overall mortality risk compared to non-exposure. Risk reduction correlated with PDE-5i exposure level.
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Affiliation(s)
- Robert A Kloner
- Huntington Medical Research Institutes, Pasadena, CA, United States.,Keck School of Medicine, Department of Medicine, Division of Cardiovascular Medicine, Los Angeles, CA, United States
| | - Eric Stanek
- HealthCore Inc., Wilmington, DE, United States.,Anthem, Inc., Indianapolis, IN, United States
| | | | | | | | - Julia Bradsher
- Huntington Medical Research Institutes, Pasadena, CA, United States
| | - Raymond C Rosen
- Department of Psychiatry and Behavioral Sciences, School of Medicine, University of California, San Francisco, CA, United States
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de Paula LJC, Uchida AH, Rezende PC, Soares P, Scudeler TL. Protective or Inhibitory Effect of Pharmacological Therapy on Cardiac Ischemic Preconditioning: A Literature Review. Curr Vasc Pharmacol 2022; 20:409-428. [PMID: 35986546 DOI: 10.2174/1570161120666220819163025] [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: 03/21/2022] [Revised: 05/23/2022] [Accepted: 05/31/2022] [Indexed: 01/25/2023]
Abstract
Ischemic preconditioning (IP) is an innate phenomenon, triggered by brief, non-lethal cycles of ischemia/reperfusion applied to a tissue or organ that confers tolerance to a subsequent more prolonged ischemic event. Once started, it can reduce the severity of myocardial ischemia associated with some clinical situations, such as percutaneous coronary intervention (PCI) and intermittent aortic clamping during coronary artery bypass graft surgery (CABG). Although the mechanisms underlying IP have not been completely elucidated, several studies have shown that this phenomenon involves the participation of cell triggers, intracellular signaling pathways, and end-effectors. Understanding this mechanism enables the development of preconditioning mimetic agents. It is known that a range of medications that activate the signaling cascades at different cellular levels can interfere with both the stimulation and the blockade of IP. Investigations of signaling pathways underlying ischemic conditioning have identified a number of therapeutic targets for pharmacological manipulation. This review aims to present and discuss the effects of several medications on myocardial IP.
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Affiliation(s)
| | | | - Paulo Cury Rezende
- Instituto do Coração (InCor), Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Paulo Soares
- Instituto do Coração (InCor), Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Thiago Luis Scudeler
- Instituto do Coração (InCor), Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
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Banjac NM, Vasović VM, Stilinović NP, Prodanović DV, Tomas Petrović AD, Vasović LV, Jakovljević VL. Tadalafil in Increasing Doses: The Influence on Coronary Blood Flow and Oxidative Stress in Isolated Rat Hearts. Pharmacology 2021; 107:150-159. [PMID: 34903698 DOI: 10.1159/000520498] [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: 07/06/2021] [Accepted: 10/27/2021] [Indexed: 11/19/2022]
Abstract
INTRODUCTION This study aimed to assess the influence of different doses of tadalafil on coronary flow and oxidative stress in isolated rat hearts. METHODS The hearts of male Wistar albino rats (n = 48) were retrogradely perfused according to the Langendorff technique at gradually increased constant perfusion pressure (CPP) (40-120 mm Hg). Coronary flow and oxidative stress markers: nitrite oxide (NO) outflow and superoxide anion production in coronary effluent were measured. The experiments were performed during control conditions and in the presence of tadalafil (10, 20, 50, and 200 nM) alone or with Nω-nitro-L-arginine monomethyl ester (L-NAME) (30 μM). RESULTS Tadalafil administration significantly increased coronary flow at all CPP values at all administered doses. Tadalafil led to an increase in the NO levels, but a statistically significant NO release increase was found only at the highest dose and highest CPP. Tadalafil did not significantly affect the release of O2-. After inhibiting the nitrite oxide synthase system by L-NAME, tadalafil-induced changes in cardiac flow and NO levels were reversed. L-NAME administration had no pronounced effect on the O2- release. CONCLUSION Tadalafil causes changes in the heart vasculature in a dose-dependent manner. It does not lead to a significant increase in the production of superoxide anion radicals.
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Affiliation(s)
- Nada M Banjac
- University of Banja Luka, Faculty of Medicine, Banja Luka, Bosnia and Herzegovina
| | - Velibor M Vasović
- Department of Pharmacology, Toxicology and Clinical Pharmacology, University of Novi Sad, Faculty of Medicine, Novi Sad, Serbia
| | - Nebojša P Stilinović
- Department of Pharmacology, Toxicology and Clinical Pharmacology, University of Novi Sad, Faculty of Medicine, Novi Sad, Serbia
| | - Dušan V Prodanović
- Department of Pharmacology, Toxicology and Clinical Pharmacology, University of Novi Sad, Faculty of Medicine, Novi Sad, Serbia
| | - Ana D Tomas Petrović
- Department of Pharmacology, Toxicology and Clinical Pharmacology, University of Novi Sad, Faculty of Medicine, Novi Sad, Serbia
| | | | - Vladimir Lj Jakovljević
- Department of Physiology, University of Kragujevac, Faculty of Medical Sciences, Kragujevac, Serbia
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6
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Andersson DP, Landucci L, Lagerros YT, Grotta A, Bellocco R, Lehtihet M, Holzmann MJ. Association of Phosphodiesterase-5 Inhibitors Versus Alprostadil With Survival in Men With Coronary Artery Disease. J Am Coll Cardiol 2021; 77:1535-1550. [PMID: 33766260 DOI: 10.1016/j.jacc.2021.01.045] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/27/2021] [Accepted: 01/28/2021] [Indexed: 01/25/2023]
Abstract
BACKGROUND Phosphodiesterase 5 inhibitor (PDE5i) treatment is associated with reduced mortality compared with no treatment for erectile dysfunction after myocardial infarction (MI). OBJECTIVES This study sought to investigate the association between treatment with PDE5i or alprostadil and outcomes in men with stable coronary artery disease. METHODS All Swedish men with a prior MI or revascularization who received PDE5i or alprostadil during 2006 through 2013 at >6 months after the event were included, using the Swedish Patient Register and the Swedish Prescribed Drug Register. Cox regression was used to estimate adjusted hazard ratios with 95% confidence intervals for all-cause mortality, MI, heart failure, cardiovascular mortality, noncardiovascular mortality, cardiac revascularization, peripheral arterial disease, and stroke in men treated with PDE5i versus alprostadil. RESULTS This study included 16,548 men treated with PDE5i and 1,994 treated with alprostadil. The mean follow-up was 5.8 years, with 2,261 deaths (14%) in the PDE5i group and 521 (26%) in the alprostadil group. PDE5i compared with alprostadil treatment was associated with lower mortality (hazard ratio: 0.88; 95% confidence interval: 0.79 to 0.98) and with similar associations for MI, heart failure, cardiovascular mortality, and revascularization. When quintiles (q) of filled PDE5i prescriptions were compared using q1 as reference, patients in q3, q4, and q5 had lower all-cause mortality. Among alprostadil users, those in q5 had a lower all-cause mortality compared to q1. CONCLUSIONS In men with stable coronary artery disease, treatment with PDE5i is associated with lower risks of death, MI, heart failure, and revascularization compared with alprostadil treatment. Although the decrease in all-cause mortality was PDE5i dose dependent, the data do not permit the inference of causality or any clinical benefits of PDE5i because of the observational study design.
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Affiliation(s)
- Daniel P Andersson
- Department of Medicine Huddinge H7, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Laura Landucci
- Functional Area of Emergency Medicine, Karolinska University Hospital, Huddinge, Stockholm, Sweden
| | - Ylva Trolle Lagerros
- Department of Medicine, Clinical Epidemiology Unit, Karolinska University Hospital, Stockholm, Sweden; Center for Obesity, Academic Specialist Center, Stockholm Health Services, Stockholm, Sweden
| | - Alessandra Grotta
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Rino Bellocco
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden; Department of Statistics and Quantitative Methods, University of Milano-Bicocca, Milan, Italy
| | - Mikael Lehtihet
- Department of Medicine Huddinge H7, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Martin J Holzmann
- Department of Medicine, Clinical Epidemiology Unit, Karolinska University Hospital, Stockholm, Sweden; Department of Emergency and Reparative Medicine, Karolinska University Hospital, Stockholm, Sweden.
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7
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Ala M, Mohammad Jafari R, Dehpour AR. Sildenafil beyond erectile dysfunction and pulmonary arterial hypertension: Thinking about new indications. Fundam Clin Pharmacol 2020; 35:235-259. [PMID: 33226665 DOI: 10.1111/fcp.12633] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 11/06/2020] [Accepted: 11/20/2020] [Indexed: 12/13/2022]
Abstract
Sildenafil, approved two decades ago, is the inhibitor of phosphodiesterase 5 (PDE5). First of all, it was designated for angina pectoris, but soon it showed a wonderful efficacy in erectile dysfunction (ED) and then pulmonary arterial hypertension (PAH). Due to the distribution of phosphodiesterase (PDE) in almost all organs, maybe it effects other diseases. Hence, a great number of investigations began to understand the role of PDEi in different organs. Preliminary research on sildenafil in cell culture and animal models has yielded promising results. Soon, a greater number of animal researches and clinical trials joined them. The results disclosed sildenafil can have beneficial effects in each organ such as heart, liver, kidney, brain, and intestines. Furthermore, it has significantly improved the prognosis of organ ischemia in various animal models. Clinical trials in several diseases, such as recurrent spontaneous miscarriage, fatty liver disease, bronchopulmonary dysplasia (BPD), heart failure, and premature ejaculation (PE) brought promising results. Although some clinical trials are available on the effects of sildenafil on various diseases, further studies on humans are needed to consolidate the ultimate effects of sildenafil. The aim of this review was to describe the effects of sildenafil on each organ and explain its mechanisms of action. Further, other PDE inhibitors such as tadalafil and vardenafil have been briefly discussed in parts of this review.
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Affiliation(s)
- Moein Ala
- Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, 13145-784, Iran.,Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, 13145-784, Iran
| | - Razieh Mohammad Jafari
- Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, 13145-784, Iran
| | - Ahmad Reza Dehpour
- Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, 13145-784, Iran.,Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, 13145-784, Iran
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Armaly Z, Artol S, Jabbour AR, Saffouri A, Habashi N, Abd Elkadir A, Ghattas N, Farah R, Kinaneh S, Nseir W. Impact of pretreatment with carnitine and tadalafil on contrast-induced nephropathy in CKD patients. Ren Fail 2020; 41:976-986. [PMID: 31797710 PMCID: PMC6913644 DOI: 10.1080/0886022x.2019.1669459] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Objective: The present study assesses whether phosphodiesterase type 5 (PDE-5) inhibitor or carnitine exert nephroprotective effects against clinical contrast-induced nephropathy (CIN). Materials and Methods: The present study consisted of three groups of CKD patients. The first group was control group, who were treated with N-acetyl-L-cysteine 1 day before and on the day of radiocontrast administration. The second one was carnitine group, where the patients were infused with carnitine over 10 min 2 h prior to the radiocontrast administration and 24 h post CT. The third one was PDE-5 inhibitor group, where patients were given tadalafil 2 h prior to the administration of the radiocontrast and in the subsequent day. Urine and blood samples were collected before and at the following time sequence: 2, 6, 12, 24, 48, and 120 h after the contrast administration, for creatinine and NGAL determination. Results: Pretreated with N-acetyl-L-cysteine prior to administration of contrast media (CM) to CKD patients caused a significant increase in urinary but not of plasma neutrophil gelatinase-associated lipocalin (NGAL) and serum creatinine (SCr). In contrast, pretreatment with carnitine prevented the increase in urinary NGAL and reduced SCr below basal levels. Similarly, tadalafil administration diminished the elevation of CM-induced urinary NGAL. Conclusions: These results indicate that carnitine and PDE-5 inhibitors may comprise potential therapeutic maneuvers for CIN.
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Affiliation(s)
- Zaher Armaly
- Department of Nephrology, E.M.M.S. Hospital, and Azrieli Faculty of Medicine in Galilee, Bar- Ilan University, Zafed, Israel
| | - Suheil Artol
- Department of Radiology, E.M.M.S. Hospital, Nazareth, Israel
| | - Adel R Jabbour
- Laboratory of Medicine, E.M.M.S. Hospital, Nazareth, Israel
| | - Amer Saffouri
- Department of Internal Medicine, E.M.M.S. Hospital, Nazareth, Israel
| | - Nayef Habashi
- Department of Nephrology, HaEmeq Hospital Afula, Afula, Israel
| | - Amir Abd Elkadir
- Department of Nephrology, E.M.M.S. Hospital, and Azrieli Faculty of Medicine in Galilee, Bar- Ilan University, Zafed, Israel
| | - Naser Ghattas
- Department of Internal Medicine, The Western Galilee Hospital, Nahariya, Israel
| | - Raymond Farah
- Department of Internal Medicine "B", Ziv Medical Center, and Azrieli Faculty of Medicine in Galilee, Bar- Ilan University, Zafed, Israel
| | - Safa Kinaneh
- Department of Nephrology, E.M.M.S. Hospital, and Azrieli Faculty of Medicine in Galilee, Bar- Ilan University, Zafed, Israel
| | - William Nseir
- Department of Internal Medicine, E.M.M.S. Hospital, Nazareth, Israel
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Köktürk S, Benli E, Ayyıldız A, Cırrık S, Çetinkol Y, Ayyıldız SN, Noyan T. Positive outcomes of phosphodiesterase type 5 inhibitor on histopathologic and biochemical changes induced by ureteral obstruction. ACTA ACUST UNITED AC 2019; 65:388-393. [PMID: 30994838 DOI: 10.1590/1806-9282.65.3.388] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 10/02/2018] [Indexed: 11/21/2022]
Abstract
OBJECTIVES We examined the effects of tadalafil, one of the phosphodiesterase type 5 (PDE5) inhibitors, in a rat model of with partial and complete unilateral ureteral obstruction (UUO). METHODS The rats were divided into 5 groups: sham (n=6), partial unilateral ureteral obstruction (PUUO, n=6), PUUO with tadalafil treatment (PUUO+T; Cialis, 10 mg/72 h, intragastric; Lilly, Indianapolis, Indiana, USA), complete unilateral ureteral obstruction (CUUO, n=6), and CUUO with tadalafil treatment (CUUO+T). RESULTS Fifteen days after the UUO, the ureter presented changes in the layers of urothelium and significant infiltration of inflammatory cells in the PUUO and CUUO groups. Compared with the sham, PUUO and CUUO groups had severe increased inflammatory cell infiltration. The urothelial epithelium exhibited cell degeneration and loss because of the swollen, atrophic, and denuded epithelial cells in the PUUO and CUUO groups. In the PUUO+T and CUUO+T groups, the urothelium revealed less epithelial cell degeneration and loss.The expressions of α-smooth muscle actin (α-SMA) and transforming growth factor-β (TGF-β) exhibited up-regulation in the PUUO and CUUO groups. The expression of TGF-β decreased positively correlated with that of α-SMA in the tadalafil therapy groups, PUUO+T and CUUO+T. CONCLUSION The phosphodiesterase type 5 inhibitor's tadalafil reduced expressions of α-SMA and TGF-β in the obstructed ureters, measured by biochemical examinations. In addition, tadalafil decreased urothelium degeneration due to the decreased epithelial cell loss and inflammatory cell infiltration. Our results show that tadalafil prevents or slows down the onset of ureter inflammation and urothelial degeneration in rats with UUO.
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Affiliation(s)
- Sibel Köktürk
- Department of Histology and Embryology, Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Erdal Benli
- Department of Urology, Faculty of Medicine, Ordu University, Ordu, Turkey
| | - Ali Ayyıldız
- Department of Urology, Faculty of Medicine, Ordu University, Ordu, Turkey
| | - Selma Cırrık
- Department of Physiology, Faculty of Medicine, Ordu University, Ordu, Turkey
| | - Yeliz Çetinkol
- Department of Medical Microbiology, Faculty of Medicine, Ordu University, Ordu, Turkey
| | - Sema Nur Ayyıldız
- Department of Biochemistry, Ordu University Faculty of Medicine, Ordu, Turkey
| | - Tevfik Noyan
- Department of Biochemistry, Ordu University Faculty of Medicine, Ordu, Turkey
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10
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Elmadbouh I, Ashraf M. Tadalafil, a long acting phosphodiesterase inhibitor, promotes bone marrow stem cell survival and their homing into ischemic myocardium for cardiac repair. Physiol Rep 2018; 5:5/21/e13480. [PMID: 29138357 PMCID: PMC5688776 DOI: 10.14814/phy2.13480] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Accepted: 09/23/2017] [Indexed: 12/31/2022] Open
Abstract
The aim was to evaluate the tadalafil‐mediated effects at molecular level on bone marrow‐derived mesenchymal stem cells (MSCs) survival and their homing into the infarcted hearts to promote cardiac repair and improve function. MSCs were pretreated in vitro with inhibitors of PKG, MAPK, FasL, nitric oxide synthase (NOS) (L‐NAME), CXCR4 (AMD3100), or miR‐21 inhibitors (+/−luciferase construction +/−Fas) prior to tadalafil treatment for 2 h. These MSCs were then subjected to H2O2 stress to assess their injury. Rats were subjected to acute myocardial infarction (AMI), and then followed by injection of saline or 1.5 x 106 MSCs‐treated ± tadalafil into infarcted and peri‐infarcted area. In another group, AMI was performed in 1‐month post‐myelo‐ablated rats and were injected intraperitoneally (IP) with tadalafil ± AMD3100 or L‐NAME for 5 days. Also, in another group, AMI mice were treated with IP ± tadalafil before intravenous injection with 111In‐oxine‐MSCs followed by CT/SPECT imaging to locate mobilized MSCs. Cardiac function was assessed by echocardiography. MSCs and heart extracts were analyzed by molecular bioassays. Tadalafil‐treated MSCs had higher expression of cGMP, NOS, SDF‐1α, p‐VASP, p‐Erk1/2, p‐STAT3, p‐Akt, PKG1 and Bcl‐xl; expression of these molecules was reduced with PKG1, MAPK, NOS or FasL inhibitors. Tadalafil inhibited apoptosis through increased miR‐21 expression and improved cell survival by inhibiting Fas (restored by PKG1, MAPK or miR‐21 inhibitors). In vivo, heart function, grafted cell survival, MSCs mobilization and homing were improved in tadalafil‐treated AMI animals versus controls. Conclusions: Tadalafil prolonged MSCs survival via up‐regulation of miR‐21 dependent suppression of Fas, and increased MSCs mobilization and their homing into infarcted myocardium resulting in improved cardiac repair and function.
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Affiliation(s)
- Ibrahim Elmadbouh
- Department of Emergency Medicine, Davis Heart and Lung Research Institute, Wexner Medical Center, Ohio State University, Columbus, Ohio.,Faculty of Medicine, Menoufia University, Shebin Elkom, Egypt
| | - Muhammad Ashraf
- Department of Emergency Medicine, Davis Heart and Lung Research Institute, Wexner Medical Center, Ohio State University, Columbus, Ohio
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11
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Wietzikoski EGG, Foiatto JC, Czeczko NG, Malafaia O, Koleski FC, Mierzwa TC, Gomes RDPX. Tadalafil protector effect during ischemia-reperfusion in rats. Acta Cir Bras 2017; 32:973-983. [DOI: 10.1590/s0102-865020170110000009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Accepted: 10/08/2017] [Indexed: 05/29/2023] Open
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12
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Andersson DP, Trolle Lagerros Y, Grotta A, Bellocco R, Lehtihet M, Holzmann MJ. Association between treatment for erectile dysfunction and death or cardiovascular outcomes after myocardial infarction. Heart 2017; 103:1264-1270. [PMID: 28280146 PMCID: PMC5537549 DOI: 10.1136/heartjnl-2016-310746] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 02/03/2017] [Indexed: 12/13/2022] Open
Abstract
Objective Erectile dysfunction (ED) is associated with an increased risk of cardiovascular disease in healthy men. However, the association between treatment for ED and death or cardiovascular outcomes after a first myocardial infarction (MI) is unknown. Methods In a Swedish nationwide cohort study all men <80 years of age without prior MI, or cardiac revascularisation, hospitalised for MI during 2007–2013 were included. Treatment for ED, defined as dispensed phosphodiesterase-5 inhibitors or alprostadil, was related to risk of death, MI, cardiac revascularisation or heart failure. Results Forty-three thousand one hundred and forty-five men with mean age 64 (±10) years were included, of whom 7.1% had ED medication dispensed during a mean 3.3 years (141 739 person-years) of follow-up. Men with, compared with those without treatment for ED, had a 33% lower mortality (adjusted HR 0.67 (95%CI 0.55 to 0.81)), and 40% lower risk of hospitalisation for heart failure (HR 0.60 (95% CI 0.44 to 0.82)). There was no association between treatment with alprostadil and mortality. The adjusted risk of death in men with 1, 2–5 and >5 dispensed prescriptions of phosphodiesterase-5 inhibitors was reduced by 34% (HR 0.66 (95% CI 0.38 to 1.15), 53% (HR 0.47 (95% CI 0.26 to 0.87) and 81% (HR 0.19 (95% CI 0.08 to 0.45), respectively, when compared with alprostadil treatment. Conclusions Treatment for ED after a first MI was associated with a reduced mortality and heart failure hospitalisation. Only men treated with phosphodiesterase-5 inhibitors had a reduced risk, which appeared to be dose-dependent.
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Affiliation(s)
- Daniel P Andersson
- Department of Medicine, Karolinska Institutet, Unit of Endocrinology, Metabolism and Diabetes, Karolinska University Hospital, Stockholm, Sweden
| | - Ylva Trolle Lagerros
- Department of Medicine, Clinical Epidemiology Unit, Karolinska Institutet, Stockholm, Sweden
| | - Alessandra Grotta
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Rino Bellocco
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.,Department of Statistics and Quantitative Methods, University of Milano-Bicocca, Milan, Italy
| | - Mikael Lehtihet
- Department of Medicine, Karolinska Institutet, Unit of Endocrinology, Metabolism and Diabetes, Karolinska University Hospital, Stockholm, Sweden
| | - Martin J Holzmann
- Department of Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Emergency Medicine, Karolinska University Hospital, Stockholm, Sweden
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13
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Salama A, Mostafa RE, Omara EA. Effects of phosphodiestrase type 5 inhibitors in epinephrine-induced arrhythmia in rats: Involvement of lactate dehydrogenase and creatine kinase downregulation and adiponectin expression. Hum Exp Toxicol 2017; 37:256-264. [PMID: 29233027 DOI: 10.1177/0960327117695638] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Cardiac arrhythmia is a common cause of mortality, and its progression may be due to abnormal sympathetic nerve activity and catecholamine release. Besides, lactate dehydrogenase (LDH) and creatine kinase (CK) downregulation and adiponectin expression play important roles in promoting coronary artery disease. The study aimed to examine the possible cardioprotective effect of members of phosphodiesterase type 5 (PDE-5) inhibitors in epinephrine-induced arrhythmia in rats. Arrhythmia was induced by cumulative boluses of epinephrine (4, 8, 16, 32, 64, and 128 mg/kg) given at 10-min intervals. Rats were randomly allocated into five groups. Group I: Normal control group received only saline. Group II: Rats injected with epinephrine and served as arrhythmia group. Groups III, IV, and V: Rats received daily oral sildenafil (0.5 mg/kg), vardenafil (3 mg/kg), and tadalafil (10 mg/kg), respectively, for 30 days prior to epinephrine injections. Injection of epinephrine to rats decreased heart rate and QTc interval but increased RR interval and duration of arrhythmia. Epinephrine group had lower serum reduced glutathione (GSH) and adiponectin levels and higher serum malondialdehyde (MDA), nitric oxide (NO), heart LDH, and CK contents. Histopathological investigations of epinephrine group provoked necrotic changes with strong positive immunoreactivity for caspases-3. While pretreatment of rats with PDE-5 inhibitors improved GSH and adiponectin contents, ameliorated serum MDA and NO levels and heart LDH and CK contents and corrected epinephrine-induced histopathological changes. PDE-5 inhibitors may delay epinephrine-induced arrhythmia through expression of adiponectin and downregulation of heart LDH and CK.
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Affiliation(s)
- Aaa Salama
- 1 Department of Pharmacology, National Research Centre, Giza, Egypt
| | - R E Mostafa
- 1 Department of Pharmacology, National Research Centre, Giza, Egypt
| | - E A Omara
- 2 Department of Pathology, National Research Centre, Giza, Egypt
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14
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Medeiros VDFLP, Azevedo ÍM, Carvalho MDF, Oliveira CN, Egito ESTD, Medeiros AC. The renoprotective effect of oral Tadalafil pretreatment on ischemia/reperfusion injury in rats. Acta Cir Bras 2017; 32:90-97. [DOI: 10.1590/s0102-865020170201] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 01/20/2017] [Indexed: 01/08/2023] Open
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15
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Voznesensky I, DeLay KJ, Hellstrom WJG. Advances in pharmacotherapy for erectile dysfunction and associated cardiac impact. Expert Opin Pharmacother 2016; 17:2281-2289. [DOI: 10.1080/14656566.2016.1241766] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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16
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Cameron RB, Beeson CC, Schnellmann RG. Development of Therapeutics That Induce Mitochondrial Biogenesis for the Treatment of Acute and Chronic Degenerative Diseases. J Med Chem 2016; 59:10411-10434. [PMID: 27560192 DOI: 10.1021/acs.jmedchem.6b00669] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Mitochondria have various roles in cellular metabolism and homeostasis. Because mitochondrial dysfunction is associated with many acute and chronic degenerative diseases, mitochondrial biogenesis (MB) is a therapeutic target for treating such diseases. Here, we review the role of mitochondrial dysfunction in acute and chronic degenerative diseases and the cellular signaling pathways by which MB is induced. We then review existing work describing the development and application of drugs that induce MB in vitro and in vivo. In particular, we discuss natural products and modulators of transcription factors, kinases, cyclic nucleotides, and G protein-coupled receptors.
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Affiliation(s)
- Robert B Cameron
- Department of Drug Discovery and Biomedical Sciences, Medical University of South Carolina , 280 Calhoun Street, Charleston, South Carolina 29425, United States.,College of Pharmacy, University of Arizona , 1295 N. Martin Avenue, Tucson, Arizona 85721, United States
| | - Craig C Beeson
- Department of Drug Discovery and Biomedical Sciences, Medical University of South Carolina , 280 Calhoun Street, Charleston, South Carolina 29425, United States
| | - Rick G Schnellmann
- Department of Drug Discovery and Biomedical Sciences, Medical University of South Carolina , 280 Calhoun Street, Charleston, South Carolina 29425, United States.,College of Pharmacy, University of Arizona , 1295 N. Martin Avenue, Tucson, Arizona 85721, United States
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17
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Lux A, Pokreisz P, Swinnen M, Caluwe E, Gillijns H, Szelid Z, Merkely B, Janssens SP. Concomitant Phosphodiesterase 5 Inhibition Enhances Myocardial Protection by Inhaled Nitric Oxide in Ischemia-Reperfusion Injury. ACTA ACUST UNITED AC 2015; 356:284-92. [DOI: 10.1124/jpet.115.227850] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Accepted: 11/23/2015] [Indexed: 01/12/2023]
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18
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Sousa RCD, Moreira Neto AA, Capelozzi VL, Ab'Saber AM, Rodrigues OR. Effects of vardenafil on the kidney of Wistar rats submitted to acute ischemia and reperfusion. Acta Cir Bras 2015; 30:339-44. [PMID: 26016933 DOI: 10.1590/s0102-865020150050000005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 04/18/2015] [Indexed: 11/22/2022] Open
Abstract
PURPOSE To investigate the effect of vardenafil in kidney of rats submitted to acute ischemia and reperfusion. METHODS Twenty-eight rats were randomly distributed into two groups. Right nephrectomy was performed and the vardenafil group received vardenafil solution (at a concentration of 1 mg/ml in 10 mg/kg) while the control group received 0.9% saline solution (SS) one hour prior to the ligature of the left renal pedicle. After one hour of ischemia, animals were submitted to twenty-four hours of reperfusion, followed by left nephrectomy. The kidney's histological parameters evaluated on the study included vacuolar degeneration and tubular necrosis. Apoptosis was assessed by immunohistochemistry for cleaved caspase-3 using the point-counting and digital methods (Cytophotometry). Also, a biochemical analysis for creatinine was conducted. RESULTS There were statistically significant differences between groups only with regards to the vacuolar degeneration parameter and to the cleaved caspase-3 digital method. CONCLUSION Vardenafil showed a protective effect on the kidney of rats subjected to acute ischemia and reperfusion in this model.
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19
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Saleh RM, Awadin WF, El-Shafei RA, Elseady YY, Wehaish FE, Elshal MF. Cardioprotective role of tadalafil against cisplatin-induced cardiovascular damage in rats. Eur J Pharmacol 2015; 765:574-81. [PMID: 26381656 DOI: 10.1016/j.ejphar.2015.09.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 09/09/2015] [Accepted: 09/11/2015] [Indexed: 01/23/2023]
Abstract
The present study investigated the possible cardioprotective effect of tadalafil (Tad) on cisplatin (CDDP)-induced cardiac and vascular damages in rats. A total number of seventy two healthy male albino rats initially weighting between 200 and 220 g were used and randomly divided into four groups,18 rats in each. The control group received no treatment; CDDP group received a single dose of CDDP (4 mg/kg) intraperitoneal (i.p.) per week for 4 weeks the duration of the experiment; Tad group received 0.4 mg/kg BW Tad i.p. daily and Tad +CDDP group received 0.4 mg/kg BW Tad i.p. +4 mg/kg BW CDDP i.p. The results showed that Tad was able to decrease blood pressure, heart rate, levels of serum cardiac troponin (cTn-I), malondialdehyde (MDA) and increased levels of reduced glutathione (GSH) and nitric oxide (NO) in the heart homogenate sample from CDDP treated rats. Semi-quantitative analysis showed that Tad was able to decrease the histopathological scores of cardiac muscular hyalinzation and fibrosis in three sacrifices in CDDP treated rats. CDDP treated rats showed significantly increased thickening in wall of aorta with an irregular luminal layer of endothelial cell linings in three sacrifices when it was compared to other groups. Moreover, immunohistochemical labeling of α- smooth muscle actin (α-SMA) in aorta revealed significant lower scores in Tad +CDDP group when they were compared to CDDP group. In conclusion, Tad alone did not induce any harmful effects on blood pressure, selective antioxidant, peroxidation markers or cardiac histology, in addition, Tad has a cardio-protective role against CDDP.
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Affiliation(s)
- Rasha M Saleh
- Department of Animal Physiology, Faculty of Veterinary Medicine, Mansoura University, Egypt
| | - Walaa F Awadin
- Department of Pathology, Faculty of Veterinary Medicine, Mansoura University, Egypt
| | - Reham A El-Shafei
- Department of Pharmacology, Faculty of Veterinary Medicine, Mansoura University, Mansoura, Egypt.
| | - Yousef Y Elseady
- Department of Animal Physiology, Faculty of Veterinary Medicine, Mansoura University, Egypt
| | - Faheim E Wehaish
- Department of Animal Physiology, Faculty of Veterinary Medicine, Mansoura University, Egypt
| | - Mohamed F Elshal
- Molecular Biology Department, Genetic Engineering and Biotechnology Research Institute, Sadat City University, Egypt; Department of Biochemistry, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
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20
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Erol B, Turker T, Tok A, Bektas S, Mungan G, Ozkanli S, Karakas B, Tokgoz H, Akduman B, Mungan A. The protective effects of tadalafil on renal damage following ischemia reperfusion injury in rats. Kaohsiung J Med Sci 2015; 31:454-62. [DOI: 10.1016/j.kjms.2015.06.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 04/11/2015] [Accepted: 05/11/2015] [Indexed: 12/14/2022] Open
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21
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Effects of phosphodiesterase-5 inhibitor on ischemic kidney injury during nephron sparing surgery: quantitative assessment by NGAL and KIM-1. World J Urol 2015; 33:2053-62. [DOI: 10.1007/s00345-015-1579-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 04/26/2015] [Indexed: 01/02/2023] Open
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22
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Kumar S, Ashraf M. Tadalafil, a Phosphodiesterase Inhibitor Protects Stem Cells over Longer Period Against Hypoxia/Reoxygenation Injury Through STAT3/PKG-I Signaling. Stem Cells Dev 2015; 24:1332-41. [PMID: 25602782 DOI: 10.1089/scd.2014.0288] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Pharmacological preconditioning (PC) with tadalafil, a PDE5A inhibitor, enhances protein kinase G-1 (PKG-I) activity, resulting in stem cell survival. Protection by PC had two different phases, early (2 h) and late (24 h). However, the mechanism of protection during these phases remained grossly unknown. Mesenchymal stem cells (MSCs) from adult male Fischer-344 rats were cultured and pretreated with tadalafil (100 μM) for an hour and subjected to 2 h of hypoxia (1% O2), followed by reoxygenation (HR: in vitro model mimicking ischemia/reperfusion). We observed (i) increased MSC survival with reduced cell cytotoxicity as revealed by low lactate dehydrogenase release and trypan blue staining, respectively, in tadalafil-treated cells upon HR; (ii) decrease in TUNEL positivity as well as caspase activity; (iii) an increase in pAkt/Akt, iNOS, eNOS, and pGSK3β/GSK3β during the early protection phase of PC, and this protection seemed to be a spontaneous adaptive response of MSCs against HR and was independent of tadalafil, whereas an increase in Bcl2/Bax was tadalafil dependent; and (iv) during the late phase, we observed phosphorylation of STAT3 at serine727, leading to its entry inside the nucleus and binding onto the promoter of PKG-I by three-fold (P<0.05). In conclusion, an increase in Bcl2/Bax during the early phase and transcriptional upregulation of PKG-I by STAT3 during the late phase were responsible for stem cell protection by tadalafil against ischemic injury.
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Affiliation(s)
- Sanjay Kumar
- 1Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida
| | - Muhammad Ashraf
- 2Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois
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23
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Vilela VR, de Oliveira AL, Comar JF, Peralta RM, Bracht A. Tadalafil inhibits the cAMP stimulated glucose output in the rat liver. Chem Biol Interact 2014; 220:1-11. [PMID: 24911673 DOI: 10.1016/j.cbi.2014.05.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 05/20/2014] [Accepted: 05/28/2014] [Indexed: 12/20/2022]
Abstract
The purpose of the present work was to verify if tadalafil affects hepatic glucose output, one of the primary targets of cAMP, in the isolated perfused rat liver. No effects on glycogen catabolism and oxygen uptake were found under basal conditions for tadalafil concentrations in the range between 0.25 and 10 μM. However, tadalafil had a clear and time-dependent inhibitory effect on the cAMP- and glucagon-stimulated glucose release. Constant infusion of tadalafil in the range between 0.25 and 10 μM eventually abolished 100% of the stimulatory action of those effectors. The tadalafil concentrations producing half-maximal rates of inhibition of the cAMP and glucagon stimulated glycogenolysis were 0.46±0.04 and 1.07±0.16 μM, respectively. These concentrations are close to the plasma peak concentrations in patients after ingestion of 20 mg tadalafil. The drug also diminished the activity of glycogen phosphorylase a and increased the activities of glucose 6-phosphatase, glucokinase, pyruvate kinase and glucose 6-phosphate dehydrogenase. These actions occurred only in the cellular environment. Tadalafil did not affect binding of cAMP to protein kinase A. Diminution of cAMP-stimulated glucose output is the opposite of what can be expected from a phosphodiesterase inhibition, the most common effect attributed to tadalafil. Diminution of glucose output by tadalafil can be attributed (a) to an interference with glycogen phosphorylase stimulation and (b) to an increased futile cycling of glucose 6-phosphate and glucose with a concomitant increased flow of hexose units into cellular metabolic pathways. The effects described in the present work may prove to represent important side effects of tadalafil.
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Affiliation(s)
| | | | | | | | - Adelar Bracht
- Department of Biochemistry, University of Maringá, 87020900 Maringá, Brazil.
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24
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Bice JS, Burley DS, Baxter GF. Novel approaches and opportunities for cardioprotective signaling through 3',5'-cyclic guanosine monophosphate manipulation. J Cardiovasc Pharmacol Ther 2014; 19:269-82. [PMID: 24572031 DOI: 10.1177/1074248413518971] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Limiting the injurious effects of myocardial ischemia-reperfusion is a desirable therapeutic target, which has been investigated extensively over the last three decades. Here we provide an up to date review of the literature documenting the experimental and clinical research demonstrating the effects of manipulating cGMP for the therapeutic targeting of the injurious effects of ischemic heart disease. Augmentation of the cyclic nucleotide cGMP plays a crucial role in many cardioprotective signaling pathways. There is an extensive body of literature which supports pharmacological targeting of cGMP or upstream activators in models of ischemia-reperfusion to limit injury. NO donors have long been utilised to manipulate cGMP, and more recently non-NO synthase derived NOx species have been investigated, resulting in their evaluation in clinical trials for the treatment of ischemic heart disease. Encouraging results demonstrate that natriuretic peptides are worthy candidates in manipulating cGMP and its downstream effectors to afford cytoprotection. Synthetic ligands have been designed which co-activate natriuretic peptide receptors to improve targeting this pathway. Advances have been made in targeting the soluble guanylyl cyclase which catalyzes the production of cGMP independently of the endogenous ligand NO using NO-independent stimulators and activators of sGC. These novel compounds show promise as a new class of drugs that target this signaling cascade specifically under pathological conditions when endogenous NO production may be compromised. Regulating the degradation of cGMP via phosphodiesterase inhibition also shows therapeutic potential. It is clear that production and regulation of cGMP is complex, indeed its spatial production and cellular distribution are only just emerging.
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Affiliation(s)
- Justin S Bice
- 1School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, United Kingdom
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25
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Effectiveness and Safety of Phosphodiesterase 5 Inhibitors in Patients with Cardiovascular Disease and Hypertension. Curr Hypertens Rep 2013; 15:475-83. [DOI: 10.1007/s11906-013-0377-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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26
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Koka S, Das A, Salloum FN, Kukreja RC. Phosphodiesterase-5 inhibitor tadalafil attenuates oxidative stress and protects against myocardial ischemia/reperfusion injury in type 2 diabetic mice. Free Radic Biol Med 2013; 60:80-8. [PMID: 23385031 DOI: 10.1016/j.freeradbiomed.2013.01.031] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Revised: 01/04/2013] [Accepted: 01/29/2013] [Indexed: 12/21/2022]
Abstract
Diabetic patients exhibit increased risk for the development of cardiovascular diseases primarily because of impaired nitric oxide (NO) bioavailability. The phosphodiesterase-5 (PDE-5) inhibitor sildenafil restores NO signaling and protects against ischemia/reperfusion (I/R) injury. In this study, we determined the effect of the long-acting PDE-5 inhibitor tadalafil on diabetes-associated complications and its role in attenuating oxidative stress after I/R injury in type 2 diabetic db/db mice. Adult male db/db mice (n=40/group) were randomized to receive dimethyl sulfoxide (10% DMSO, 0.2ml, ip) or tadalafil (1mg/kg in 10% DMSO, ip) for 28 days. After 28 days treatment, the hearts were isolated and subjected to 30min global ischemia followed by 60min reperfusion in the Langendorff mode. Infarct size was measured using computer morphometry of tetrazolium-stained sections. Cardiomyocytes were isolated from a subset of hearts and subjected to 40min simulated ischemia followed by 1h of reoxygenation (SI/RO). Dichlorodihydrofluorescein diacetate and JC-1 staining was used to measure reactive oxygen species (ROS) generation and mitochondrial membrane potential (Δψm), respectively. Another subset of hearts was used for the estimation of lipid peroxidation, glutathione, and the expression of myocardial pRac1, Rac1, gp91(phox), p47(phox), and p67(phox) by Western blot. Tadalafil treatment improved the metabolic status and reduced infarct size compared to the untreated db/db mice (21.2±1.8% vs 45.8±2.8%; p<0.01). The db/db mice showed enhanced oxidative stress in cardiomyocytes as indicated by a significant increase in ROS production. Cardiac NAD(P)H oxidase activity, lipid peroxidation, and oxidized glutathione were also increased in db/db mice compared to nondiabetic control animals. Tadalafil treatment in db/db mice suppressed oxidative stress, attenuated myocardial expression of pRac1 and gp91(phox), and also preserved the loss of Δψm in cardiomyocytes after SI/RO. In conclusion, these results demonstrate that chronic treatment with tadalafil attenuates oxidative stress and improves mitochondrial integrity while providing powerful cardioprotective effects in type 2 diabetes.
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MESH Headings
- Animals
- Apoptosis/drug effects
- Carbolines/administration & dosage
- Cardiotonic Agents/administration & dosage
- Cyclic Nucleotide Phosphodiesterases, Type 5/metabolism
- Diabetes Mellitus, Experimental/drug therapy
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Experimental/pathology
- Diabetes Mellitus, Type 2/drug therapy
- Diabetes Mellitus, Type 2/metabolism
- Diabetes Mellitus, Type 2/physiopathology
- Humans
- Mice
- Mitochondria, Heart/drug effects
- Mitochondria, Heart/pathology
- Myocardial Reperfusion Injury/drug therapy
- Myocardial Reperfusion Injury/pathology
- Myocytes, Cardiac/cytology
- Myocytes, Cardiac/drug effects
- Nitric Oxide/metabolism
- Oxidative Stress/drug effects
- Oxidative Stress/genetics
- Phosphodiesterase 5 Inhibitors/administration & dosage
- Reactive Oxygen Species/metabolism
- Tadalafil
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Affiliation(s)
- Saisudha Koka
- Pauley Heart Center, Division of Cardiology, Department of Internal Medicine, Virginia Commonwealth University Medical Center, Richmond, VA 23298-0204, USA
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Abstract
Male sexuality in the elderly is an important issue with a growing relevance. In contrast to the assumption of an asexual state when becoming older, recent representative surveys show that the majority of men maintain sexual desires and fantasies into old age. Sexual activity primarily depends on the availability of a partner and on maintaining intimacy and sexuality in the face of changes in the sexual response cycle and increasing comorbidity. This review aims to clarify the normal aging process, the sexual behavior of aging males and the prevalence of sexual dysfunction.
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Affiliation(s)
- L Rinnab
- Schwerpunkt Medikamentöse Tumortherapie & Andrologie, Praxis für Urologie und Männermedizin Neu-Ulm, Augsburgerstraße 1a, 89231 Neu-Ulm, Deutschland.
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28
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Sohotnik R, Nativ O, Abbasi A, Awad H, Frajewicki V, Bishara B, Sukhotnik I, Armaly Z, Aronson D, Heyman SN, Nativ O, Abassi Z. Phosphodiesterase-5 inhibition attenuates early renal ischemia-reperfusion-induced acute kidney injury: assessment by quantitative measurement of urinary NGAL and KIM-1. Am J Physiol Renal Physiol 2013; 304:F1099-104. [PMID: 23364806 DOI: 10.1152/ajprenal.00649.2012] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Acute kidney injury (AKI) is a common clinical problem that still lacks effective treatment. Phosphodiesterase-5 (PDE5) inhibitors possess anti-apoptotic and anti-oxidant properties, making it a promising therapy for ischemia-reperfusion (I/R) injury of various organs. The present study evaluated the early nephroprotective effects of Tadalafil, a PDE5 inhibitor, in an experimental model of renal I/R. Sprague-Dawley rats were divided into two groups: vehicle-treated I/R (n = 10), and Tadalafil (10 mg/kg po)-treated I/R group (n = 11). After removal of the right kidney and collection of two baseline urine samples, the left renal artery was clamped for 45 min followed by reperfusion for 60, 120, 180, and 240 min. Functional and histological parameters of the kidneys from the various groups were determined. In the vehicle-treated I/R group, glomerular filtration rate was significantly reduced compared with that in normal kidneys. In addition, the ischemic kidney showed remarkable cast formation, necrosis, and congestion, a consistent pattern of acute tubular necrosis. Furthermore, urinary excretion of NGAL and KIM-1, two novel biomarkers of kidney injury, substantially increased following I/R insult. In contrast, Tadalafil treatment resulted in a significant improvement in kidney function and amelioration of the adverse histological alterations of the ischemic kidney. Noteworthy, the urinary excretion of NGAL and KIM-1 markedly decreased in the Tadalafil-treated I/R group. These findings demonstrate that Tadalafil possesses early nephroprotective effects in rat kidneys subjected to I/R insult. This approach may suggest a prophylactic therapy for patients with ischemic AKI.
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Affiliation(s)
- Rima Sohotnik
- Department of Nephrology and Hypertension, Carmel Medical Center, Haifa, Israel
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Wang JS, Kovanecz I, Vernet D, Nolazco G, Kopchok GE, Chow SL, White RA, Gonzalez-Cadavid NF. Effects of sildenafil and/or muscle derived stem cells on myocardial infarction. J Transl Med 2012; 10:159. [PMID: 22871104 PMCID: PMC3476974 DOI: 10.1186/1479-5876-10-159] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Accepted: 07/16/2012] [Indexed: 12/05/2022] Open
Abstract
Background Previous studies have shown that long-term oral daily PDE 5 inhibitors (PDE5i) counteract fibrosis, cell loss, and the resulting dysfunction in tissues of various rat organs and that implantation of skeletal muscle-derived stem cells (MDSC) exerts some of these effects. PDE5i and stem cells in combination were found to be more effective in non-MI cardiac repair than each treatment separately. We have now investigated whether sildenafil at lower doses and MDSC, alone or in combination are effective to attenuate LV remodeling after MI in rats. Methods MI was induced in rats by ligature of the left anterior descending coronary artery. Treatment groups were: “Series A”: 1) untreated; 2) oral sildenafil 3 mg/kg/day from day 1; and “Series B”: intracardiac injection at day 7 of: 3) saline; 4) rat MDSC (106 cells); 5) as #4, with sildenafil as in #2. Before surgery, and at 1 and 4 weeks, the left ventricle ejection fraction (LVEF) was measured. LV sections were stained for collagen, myofibroblasts, apoptosis, cardiomyocytes, and iNOS, followed by quantitative image analysis. Western blots estimated angiogenesis and myofibroblast accumulation, as well as potential sildenafil tachyphylaxis by PDE 5 expression. Zymography estimated MMPs 2 and 9 in serum. Results As compared to untreated MI rats, sildenafil improved LVEF, reduced collagen, myofibroblasts, and circulating MMPs, and increased cardiac troponin T. MDSC replicated most of these effects and stimulated cardiac angiogenesis. Concurrent MDSC/sildenafil counteracted cardiomyocyte and endothelial cells loss, but did not improve LVEF or angiogenesis, and upregulated PDE 5. Conclusions Long-term oral sildenafil, or MDSC given separately, reduce the MI fibrotic scar and improve left ventricular function in this rat model. The failure of the treatment combination may be due to inducing overexpression of PDE5.
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Affiliation(s)
- Judy Sc Wang
- Department of Surgery, Los Angeles Biomedical Research Institute (LABioMed) at Harbor-UCLA Medical Center, Torrance, CA, USA
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Porst H, Hell-Momeni K, Büttner H. Chronic PDE-5 inhibition in patients with erectile dysfunction – a treatment approach using tadalafil once-daily. Expert Opin Pharmacother 2012; 13:1481-94. [DOI: 10.1517/14656566.2012.693162] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Chrysant SG, Chrysant GS. The pleiotropic effects of phosphodiesterase 5 inhibitors on function and safety in patients with cardiovascular disease and hypertension. J Clin Hypertens (Greenwich) 2012; 14:644-9. [PMID: 22947364 DOI: 10.1111/j.1751-7176.2012.00669.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Phosphodiesterase 5 (PDE-5) inhibitors are selective blockers of PDE-5, which catalyzes the hydrolysis of cyclic guanosine monophosphate (cGMP) to its corresponding monophosphates. cGMP is a potent vasodilator and nitric oxide donor. Since PDE-5 is widely distributed in the body, it was hypothesized that inhibition of its actions could lead to significant vasodilation, which could benefit patients with coronary artery disease. This hypothesis led to the development of PDE-5 inhibitors, the first being sildenafil citrate. Studies of sildenafil in patients with coronary artery disease demonstrated a modest cardiovascular effect but a potent action on penile erection in men, resulting in sildenafil becoming first-line treatment of erectile dysfunction. Two more PDE-5 inhibitors are now US Food and Drug Administration-approved (vardenafil and tadalafil) for the treatment of erectile dysfunction. Recent studies have demonstrated several beneficial pleiotropic cardiovascular effects of PDE-5 inhibitors in patients with erectile dysfunction and multiple comorbidities, including coronary artery disease, heart failure, hypertension, and diabetes mellitus. Treatment of these conditions with PDE-5 inhibitors has been very effective, safe, and well tolerated. Drug interactions have been minimal with the exception of nitrates, where coadministration may result in severe vasodilation and hypotension. These beneficial pleiotropic and safe cardiovascular effects of PDE-5 inhibitors will be discussed in this concise review.
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Affiliation(s)
- Steven G Chrysant
- Oklahoma Cardiovascular and Hypertension Center and the University of Oklahoma, Oklahoma City, OK, USA.
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Gerczuk PZ, Kloner RA. An update on cardioprotection: a review of the latest adjunctive therapies to limit myocardial infarction size in clinical trials. J Am Coll Cardiol 2012; 59:969-78. [PMID: 22402067 DOI: 10.1016/j.jacc.2011.07.054] [Citation(s) in RCA: 165] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 06/13/2011] [Accepted: 07/19/2011] [Indexed: 12/13/2022]
Abstract
Acute myocardial infarction (AMI) with subsequent left ventricular dysfunction and heart failure continues to be a major cause of morbidity and mortality in the Western world. Rapid advances in the treatment of AMI, mainly through timely reperfusion, have substantially improved outcomes in patients presenting with acute coronary syndrome and particularly ST-segment elevation myocardial infarction. A vast amount of research, both translational and clinical, has been published on various pharmacological and interventional techniques to prevent myocardial cell death during the time of ischemia and subsequent reperfusion. Several methods of cardioprotection have shown the ability to limit myocardial infarction size in clinical trials. Examples of interventional techniques that have proven beneficial are ischemic post-conditioning and remote ischemic per-conditioning, both of which can reduce infarction size. Lowering core body temperature with cold saline infusion and cooling catheters have also been shown to be effective in certain circumstances. The most promising pharmaceutical cardioprotective agents at this time appear to be adenosine, atrial natriuretic peptide, and cyclosporine, with other potentially effective medications in the pipeline. Additional pre-clinical and clinical research is needed to further investigate newer cardioprotective strategies to continue the current trend of improving outcomes following AMI.
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Affiliation(s)
- Paul Z Gerczuk
- Heart Institute, Good Samaritan Hospital, Wilshire Boulevard, Los Angeles, CA 90017, USA
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Dai W, Kloner RA. Is inhibition of phosphodiesterase type 5 by sildenafil a promising therapy for volume-overload heart failure? Circulation 2012; 125:1341-3. [PMID: 22319107 DOI: 10.1161/circulationaha.112.094912] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Chronic treatment with long acting phosphodiesterase-5 inhibitor tadalafil alters proteomic changes associated with cytoskeletal rearrangement and redox regulation in Type 2 diabetic hearts. Basic Res Cardiol 2012; 107:249. [PMID: 22311732 DOI: 10.1007/s00395-012-0249-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 01/16/2012] [Accepted: 01/27/2012] [Indexed: 01/09/2023]
Abstract
Diabetic patients are prone to metabolic perturbations that progressively contribute to structural, functional and proteomic alterations in the myocardium. Phosphodiesterase-5 (PDE-5) inhibitors exhibit cardioprotective effects against ischemic/reperfusion injury, however the effects of chronic administration of PDE-5 inhibitors, particularly under diabetic conditions, remain unknown. Hence, the present study was designed to identify novel protein targets related to long-acting PDE-5 inhibitor tadalafil-induced cardioprotection in diabetes. Using two-dimensional differential in-gel electrophoresis with 3 CyDye labeling and MALDI-TOF/TOF tandem mass spectrometry we identified alterations in the expressions of cardiac proteins in diabetic db/db mice treated with tadalafil. Tadalafil reversed the coordinated alterations of cytoskeletal/contractile proteins such as myosin light chain (MLY) 2 and 4, myosin heavy chain α and myosin-binding protein C which contributes to contractile dysfunction. The expression of intermediate filament protein vimentin and extra-cellular matrix proteins like cysteine and glycine rich protein-3 and collagen type VI α were upregulated in db/db mice indicating cardiac remodeling in diabetes. These detrimental proteomic alterations were reflected in cardiac function which were reversed in tadalafil treated mice. Tadalafil also enhanced antioxidant enzyme glutathione S-transferase Kappa-1 (GSKT-1) and downregulated redox regulatory chaperones like heat shock protein 8 (HSPA8), and 75 kD glucose regulatory protein (75GRP). Furthermore, tadalafil treatment significantly attenuated GSSG/GSH ratio and improved the metabolic status of db/db mice. Chronic treatment with tadalafil in db/db mice modulates proteins involved in cytoskeletal rearrangement and redox signaling of the heart, which may explain the beneficial effects of PDE-5 inhibition in diabetes.
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Gasanov F, Aytac B, Vuruskan H. The effects of tadalafil on renal ischemia reperfusion injury: an experimental study. Bosn J Basic Med Sci 2012; 11:158-62. [PMID: 21875417 DOI: 10.17305/bjbms.2011.2567] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Many pharmacological agents were investigated for the prevention of renal ischemic reperfusion (I/R) injury as well as the phosphodiesterase (PDE) inhibitors. The aim of the study was to examine the possible renoprotective effect of a member in this family, tadalafil (Td) on I/R injury. Thirty-six Spraque Dawley rats were allocated to six groups as; control, sham, ischemia (I), ischemia/reperfusion (I/R), Td pretreatment ischemia (Td/I) and Td pretreatment ischemia/reperfusion (Td/IR) groups. Right nephrectomy was performed in all groups. Td was dissolved in saline solution and given as a single dose (1mg/kg) through an orogastrictube 60 min before the operation in the Td pretreatment groups. In ischemia group the left renal pedicle was occluded for 45 minutes and after than underwent left nephrectomy. In I/R group left renal pedicle was occluded for 45 minutes, reperfused for 1hour and after then underwent nephrectomy. The left kidneys were evaluated after standard laboratory procedures with regard to tubular morphology, and leukocyte infiltration. The data were analyzed by using Kruskal-Wallis test to determine differences among the groups. A p value of < 0.05 was considered significant. Renal tubular damage was significant increased in the ischemia and I/R group (Groups III and IV) when compared to those in the sham group (Group II), (p = 0.004, 0.004, respectively). Tubular damage, in the Td pretreatment ischemia (Td/I) (Group V) and Td pretreatment ischemia/reperfusion (Td/IR) (Group VI) were less than that in the ischemia group (Group III) (p= 0.010, p= 0.025, respectively). Td administration prior to the renal I/R injury attenuated these morphological disarrangements, which were observed in renal I/R. Tubular necrosis, which may be considered as an important issue of the developing renal injury, was also completely prevented with Td administration.
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Affiliation(s)
- Feyzul Gasanov
- Department of Urology, Uludag University, Gorukle, Bursa, Turkey
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Schwartz BG, Levine LA, Comstock G, Stecher VJ, Kloner RA. Cardiac Uses of Phosphodiesterase-5 Inhibitors. J Am Coll Cardiol 2012; 59:9-15. [DOI: 10.1016/j.jacc.2011.07.051] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 06/28/2011] [Accepted: 07/25/2011] [Indexed: 01/01/2023]
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Phé V, Rouprêt M. Erectile dysfunction and diabetes: a review of the current evidence-based medicine and a synthesis of the main available therapies. DIABETES & METABOLISM 2011; 38:1-13. [PMID: 22056307 DOI: 10.1016/j.diabet.2011.09.003] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2011] [Accepted: 09/25/2011] [Indexed: 12/20/2022]
Abstract
AIM This review aimed to provide an update of the epidemiology, pathophysiology and management of erectile dysfunction (ED) in diabetes patients. METHODS Data on the management of ED in diabetes patients in the literature were analyzed using Medline, and by matching the following keywords: diabetes; erectile dysfunction; endothelial dysfunction; cardiovascular disease; phosphodiesterase inhibitors; intracavernous injection; and penile prosthesis. RESULTS ED has a higher incidence in diabetic patients. The pathophysiology is multifactorial, involving endothelial dysfunction, specific complications of diabetes and psychological factors. Recent studies have shown that ED is able to predict future cardiovascular events not only in non-diabetics, but also in patients with diabetes. ED could also be a potential marker to screen for silent coronary artery disease. The management of ED has been revolutionized by the discovery of phosphodiesterase type-5 (PDE5) inhibitors, the first-line therapeutic options for diabetic men with ED that are efficient and safe. As a second line, intracavernous injections remain a gold-standard treatment, although a vacuum device can be used as well. In cases of failure, penile prosthesis may be considered. Hypogonadism, commonly found in diabetics, may require identification and treatment. Optimalized glycaemic control, management of associated co-morbidities and lifestyle modifications are essential in all patients. As ED and diabetes negatively impact male self-esteem, and generate depression and anxiety, the psychological treatment of patients is also likely to be beneficial. CONCLUSION The aetiology of diabetic ED is multifactorial. Endothelial dysfunction is the link between diabetes-induced ED and coronary artery disease. A global approach is needed for the successful management of diabetic ED.
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Affiliation(s)
- V Phé
- Urology and Andrology Academic Department of Pitié-Salpêtrière Hospital, Assistance Publique-Hôpitaux de Paris, Faculté de Médecine Pierre-et-Marie-Curie, University Paris-VI, Paris, France
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Guzeloglu M, Yalcinkaya F, Atmaca S, Bagriyanik A, Oktar S, Yuksel O, Fansa I, Hazan E. The beneficial effects of tadalafil on renal ischemia-reperfusion injury in rats. Urol Int 2010; 86:197-203. [PMID: 21160160 DOI: 10.1159/000321927] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Accepted: 09/26/2010] [Indexed: 11/19/2022]
Abstract
Acute renal failure due to ischemia-reperfusion (I/R) injury is a common complication in cardiovascular surgery. We determined the influence of tadalafil on renal injury in a renal I/R model in rats. For this purpose, 21 male Wistar albino rats were separated into 3 groups: sham, placebo and tadalafil. A right nephrectomy was performed, and the left renal pedicles were occluded for 60 min and reperfused for 60 min in the placebo and tadalafil groups. A single dose of tadalafil (10 mg/kg) through an orogastric tube was administered to the tadalafil group. Tubular atrophy with acute inflammation in renal histology, total oxidant status (TOS) and total antioxidant status (TAS) were determined in tissue homogenates. Compared to the tadalafil group, tubular atrophy and acute inflammation was significant in the placebo group. TAS levels were significantly higher in the tadalafil group compared to the placebo (p = 0.01) and sham groups (p = 0.04). While TOS levels were significantly higher in the placebo group (p = 0.03), tadalafil did not significantly alter the TOS levels. The beneficial effects of tadalafil can be attributed to its protective effects on renal tubular cells and inhibition of leukocyte infiltration in renal tissue. We think that tadalafil treatment has an important role in reducing renal injury resulting from renal I/R.
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Affiliation(s)
- Mehmet Guzeloglu
- Department of Cardiovascular Surgery, Tayfur Ata Sokmen Medical Faculty, Mustafa Kemal University, Hatay, Turkey. mehmetguzeloglu @ hotmail.com
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Koka S, Das A, Zhu SG, Durrant D, Xi L, Kukreja RC. Long-acting phosphodiesterase-5 inhibitor tadalafil attenuates doxorubicin-induced cardiomyopathy without interfering with chemotherapeutic effect. J Pharmacol Exp Ther 2010; 334:1023-30. [PMID: 20543097 DOI: 10.1124/jpet.110.170191] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Doxorubicin (DOX) is one of the most effective anticancer drugs. However, its cardiotoxicity remains a clinical concern that severely restricts its therapeutic usage. We designed this study to investigate whether tadalafil, a long-acting phosphodiesterase-5 (PDE-5) inhibitor, protects against DOX-induced cardiotoxicity. We also sought to delineate the cellular and molecular mechanisms underlying tadalafil-induced cardioprotection. Male CF-1 outbred mice were randomized into three groups (n = 15-24/group) to receive either saline (0.2 ml i.p.), DOX (15 mg/kg, given by a single intraperitoneal injection), or tadalafil (4 mg/kg p.o. daily for 9 days) plus DOX. Left ventricular function was subsequently assessed by transthoracic echocardiography and Millar conductance catheter. Cardiac contractile function was impaired by DOX, and it was significantly improved by cotreatment with tadalafil. Tadalafil attenuated DOX-induced apoptosis and depletion of prosurvival proteins, including Bcl-2 and GATA-4, in myocardium. Cardiac oxidative stress was attenuated and antioxidant capacity was enhanced by tadalafil possibly via up-regulation of mitochondrial superoxide dismutase (MnSOD). Moreover, the tadalafil-treated group demonstrated increased cardiac cGMP level and protein kinase G (PKG) activity. Tadalafil did not interfere with the efficacy of DOX in killing human osteosarcoma cells in vitro or its antitumor effect in vivo in tumor xenograft model. We conclude that tadalafil improved left ventricular function and prevented cardiomyocyte apoptosis in DOX-induced cardiomyopathy through mechanisms involving up-regulation of cGMP, PKG activity, and MnSOD level without interfering with the chemotherapeutic benefits of DOX.
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Affiliation(s)
- Saisudha Koka
- Division of Cardiology, Department of Internal Medicine, Virginia Commonwealth University Medical Center, Richmond, Virginia, USA
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Salloum FN, Chau VQ, Hoke NN, Abbate A, Varma A, Ockaili RA, Toldo S, Kukreja RC. Phosphodiesterase-5 inhibitor, tadalafil, protects against myocardial ischemia/reperfusion through protein-kinase g-dependent generation of hydrogen sulfide. Circulation 2009; 120:S31-6. [PMID: 19752383 DOI: 10.1161/circulationaha.108.843979] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Tadalafil is a novel long-acting inhibitor of phosphodiesterase-5. Because cGMP-dependent protein kinase (PKG) signaling plays a key role in cardioprotection, we hypothesized that PKG activation with tadalafil would limit myocardial ischemia/reperfusion (I/R) injury and dysfunction. Additionally, we contemplated that cardioprotection with tadalafil is mediated by hydrogen sulfide (H(2)S) signaling in a PKG-dependent fashion. METHODS AND RESULTS After baseline transthoracic echocardiography (TTE), adult ICR mice were injected i.p. with vehicle (10% DMSO) or tadalafil (1 mg/kg) with or without KT5823 (KT, PKG blocker, 1 mg/kg) or dl-propargylglycine (PAG, Cystathionine-gamma-lyase [CSE, H(2)S-producing enzyme] blocker; 50 mg/kg) 1 hour before coronary artery ligation for 30 minutes and reperfusion for 24 hours, whereas C57BL wild-type and CSE-knockout mice were treated with either vehicle or tadalafil. After reperfusion, TTE was performed and hearts were collected for infarct size (IS) measurement using TTC staining. Survival was increased with tadalafil (95%) compared with control (65%, P<0.05). Infarct size was reduced with tadalafil (13.2+/-1.7%) compared to vehicle (40.6+/-2.5%; P<0.05). KT and PAG abolished tadalafil-induced protection (IS: 39.2+/-1% and 51.2+/-2.4%, respectively) similar to genetic deletion of CSE (47.2+/-5.1%). Moreover, tadalafil preserved fractional shortening (FS: 31+/-1.5%) compared to control (FS: 22+/-4.8%, P<0.05). Baseline FS was 44+/-1.7%. KT and PAG abrogated the preservation of LV function with tadalafil by decline in FS to 17+/-1% and 23+/-3%, respectively. Compared to vehicle, myocardial H(2)S production was significantly increased with tadalafil and was abolished with KT. CONCLUSIONS PKG activation with tadalafil limits myocardial infarction and preserves LV function through H(2)S signaling.
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Affiliation(s)
- Fadi N Salloum
- Department of Internal Medicine, Virginia Commonwealth University, Richmond, 23298, USA.
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Porst H, Hell-Momeni K, Büttner H. Chronische PDE-5-Hemmung bei erektiler Dysfunktion. Urologe A 2009; 48:1318, 1320-9. [DOI: 10.1007/s00120-009-2089-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Abstract
A growing body of animal studies provides evidence for potential cardioprotective effects of inhibitors of the enzyme phosphodiesterase isoform 5. Infarct size reduction by administration of phosphodiesterase 5 inhibitors was described in various experimental models of ischaemia and reperfusion. Furthermore, potential beneficial effects were demonstrated in experimental models of congestive heart failure and left ventricular hypertrophy. Some of the observed effects resemble the basic mechanisms of ischaemic pre-conditioning, mimicking both acute and delayed effects. Other effects may be due to action on systemic and cardiac haemodynamics. Mechanisms and signalling pathways, characterized in some of the experimental models, appear to be complex: for instance, the rate of cyclic guanosine monophosphate (cGMP) synthesis and the functional compartmentalization of intracellular cGMP metabolism as well as interaction with ss-adrenergic and nitric oxide signalling may influence effects in different experimental settings. In this review, we discuss mechanisms, signalling pathways, and experimental limitations and touch on considerations for translation into potentially useful applications in the clinical arena.
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Affiliation(s)
- Thorsten Reffelmann
- Klinik und Poliklinik für Innere Medizin B, Universitätsklinikum der Ernst-Moritz-Arndt-Universität Greifswald, Friedrich-Löffler-Str. 23 a, 17475 Greifswald, Germany.
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Ahmad N, Wang Y, Ali AK, Ashraf M. Long-acting phosphodiesterase-5 inhibitor, tadalafil, induces sustained cardioprotection against lethal ischemic injury. Am J Physiol Heart Circ Physiol 2009; 297:H387-91. [PMID: 19429825 DOI: 10.1152/ajpheart.00169.2009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The ability of pharmacological preconditioning mimetics to confer long-lasting and sustained cardioprotection may be a logical criterion to develop a drug that can be used clinically for cardioprotection. We propose here that the use of long-acting phosphodiesterase-5 inhibitor, tadalafil, may confer sustained cardioprotection against ischemia. Tadalafil (5 mg/kg) was administered orally to male C57B/6J mice (n = 6 in each treatment subgroup at each time point studied). Hearts were isolated and subjected to 40 min of ischemia and 30 min of reperfusion on Langendorff's apparatus at 1, 12, 24, 36, 48, 60, 72, and 108 h after tadalafil administration. In 1- to 48-h subgroups, tadalafil was given once at 0 h only. In 60- and 72-h subgroups, tadalafil was given twice at 0 and 36 h. Similarly, in the 108-h subgroup, tadalafil was administered at 0, 36, and 72 h. In the same subgroups, wortmannin (15 microg/kg ip), an inhibitor of phosphatidylinositol 3-kinase or 5-hydroxydecanoic acid (5 mg/kg ip), an inhibitor of mitochondrial ATP-sensitive K(+) channels, was given together with tadalafil, and the hearts were subjected to ischemia-reperfusion at 36 h to determine whether the effect of tadalafil on ischemia-reperfusion injury was abolished. As a result, tadalafil treatment reduced left ventricular end-diastolic pressure and increased left ventricular developed pressure as well as reduced lactate dehydrogenase release. This protection remained till 36-40 h, and thereafter it vanished. The readministration of tadalafil at 36 and 72 h restored the protection till 108 h. Tadalafil treatment accelerated Akt phosphorylation in cardiac tissue and decreased myocyte apoptosis. The administration of wortmannin abolished the beneficial effects of tadalafil on hemodynamic parameters and myocyte apoptosis, together with significantly reduced Akt phosphorylation. 5-Hydroxydecanoic acid also abolished the antiapoptotic effect of tadalafil. It is concluded that tadalafil treatment induces the long-term protection of ischemic myocardium via phosphatidylinositol 3-kinase/Akt signaling pathway.
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Affiliation(s)
- Nauman Ahmad
- Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, OH 45267-0529, USA
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Rao YJ, Xi L. Pivotal effects of phosphodiesterase inhibitors on myocyte contractility and viability in normal and ischemic hearts. Acta Pharmacol Sin 2009; 30:1-24. [PMID: 19060915 DOI: 10.1038/aps.2008.1] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Phosphodiesterases (PDEs) are enzymes that degrade cellular cAMP and cGMP and are thus essential for regulating the cyclic nucleotides. At least 11 families of PDEs have been identified, each with a distinctive structure, activity, expression, and tissue distribution. The PDE type-3, -4, and -5 (PDE3, PDE4, PDE5) are localized to specific regions of the cardiomyocyte, such as the sarcoplasmic reticulum and Z-disc, where they are likely to influence cAMP/cGMP signaling to the end effectors of contractility. Several PDE inhibitors exhibit remarkable hemodynamic and inotropic properties that may be valuable to clinical practice. In particular, PDE3 inhibitors have potent cardiotonic effects that can be used for short-term inotropic support, especially in situations where adrenergic stimulation is insufficient. Most relevant to this review, PDE inhibitors have also been found to have cytoprotective effects in the heart. For example, PDE3 inhibitors have been shown to be cardioprotective when given before ischemic attack, whereas PDE5 inhibitors, which include three widely used erectile dysfunction drugs (sildenafil, vardenafil and tadalafil), can induce remarkable cardioprotection when administered either prior to ischemia or upon reperfusion. This article provides an overview of the current laboratory and clinical evidence, as well as the cellular mechanisms by which the inhibitors of PDE3, PDE4 and PDE5 exert their beneficial effects on normal and ischemic hearts. It seems that PDE inhibitors hold great promise as clinically applicable agents that can improve cardiac performance and cell survival under critical situations, such as ischemic heart attack, cardiopulmonary bypass surgery, and heart failure.
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Twenty years of IJIR. Int J Impot Res 2008; 20:429-30. [PMID: 18787555 DOI: 10.1038/ijir.2008.37] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Kloner RA. Erectile dysfunction: the new harbinger for major adverse cardiac events in the diabetic patient. J Am Coll Cardiol 2008; 51:2051-2. [PMID: 18498960 DOI: 10.1016/j.jacc.2007.11.084] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2007] [Accepted: 11/27/2007] [Indexed: 10/22/2022]
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Salloum FN, Abbate A, Das A, Houser JE, Mudrick CA, Qureshi IZ, Hoke NN, Roy SK, Brown WR, Prabhakar S, Kukreja RC. Sildenafil (Viagra) attenuates ischemic cardiomyopathy and improves left ventricular function in mice. Am J Physiol Heart Circ Physiol 2008. [DOI: 10.1152/ajpheart.ajpheart.91438.2007] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We tested the hypothesis that chronic treatment with sildenafil attenuates myocardial infarction (MI)-induced heart failure. Sildenafil has potent protective effects against necrosis and apoptosis following ischemia-reperfusion in the intact heart and cardiomyocytes. ICR mice underwent MI by left anterior descending coronary artery ligation and were treated with sildenafil (0.71 mg/kg bid) or saline for 4 wk. Infarct size (IS) was measured 24 h postinfarction, and apoptosis was measured by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling. Left ventricular end-diastolic diameter (LVEDD) and fractional shortening (FS) were measured by echocardiography. Sildenafil reduced IS (40.0 ± 4.6%) compared with that in saline (69.6 ± 4.1%, P < 0.05). NG-nitro-l-arginine methyl ester, a nitric oxide synthase (NOS) inhibitor (15 mg/kg bid), blocked the protective effect of sildenafil (IS, 60.2 ± 1.6%, P < 0.05 vs. sildenafil). Western blot analysis revealed a significant increase in endothelial NOS/inducible NOS proteins 24 h post-MI after treatment with sildenafil versus saline. Apoptosis decreased from 2.4 ± 0.3% with saline to 1.2 ± 0.1% with sildenafil ( P < 0.05) on day 7 and from 2.0 ± 0.2% with saline to 1.2 ± 0.1% with sildenafil on day 28 ( P < 0.05), which was associated with an early increase in the Bcl-2-to-Bax ratio. LVEDD increased from baseline value of 3.6 ± 0.1 to 5.2 ± 0.2 and to 5.5 ± 0.1 mm on days 7 and 28, respectively, with saline ( P < 0.05) but was attenuated to 4.4 ± 0.2 and 4.4 ± 0.1 mm following sildenafil treatment on days 7 and 28, respectively ( P > 0.05 vs. baseline). FS significantly improved post-MI with sildenafil. A marked decline in cardiac hypertrophy was observed with sildenafil, which paralleled a reduction in pulmonary edema. Survival rate was lower with saline (36%) compared with sildenafil (93%, P < 0.05). Sildenafil attenuates ischemic cardiomyopathy in mice by limiting necrosis and apoptosis and by preserving left ventricular function possibly through a nitric oxide-dependent pathway.
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Reffelmann T, Kieback A, Kloner RA. The cardiovascular safety of tadalafil. Expert Opin Drug Saf 2008; 7:43-52. [DOI: 10.1517/14740338.7.1.43] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Thorsten Reffelmann
- Klinik und Poliklinik für Innere Medizin B, Universitätsklinik der, Ernst-Moritz-Arndt-Universität Greifswald, Friedrich-Löffler Str. 23 a, 17475 Greifswald, Germany ;
- University of Southern California, The Heart Institute, Good Samaritan Hospital, Division of Cardiology, 1225 Wilshire Boulevard, Los Angeles, CA 90017-2395, USA
| | - Arne Kieback
- Klinik und Poliklinik für Innere Medizin B, Universitätsklinik der, Ernst-Moritz-Arndt-Universität Greifswald, Friedrich-Löffler Str. 23 a, 17475 Greifswald, Germany ;
| | - Robert A Kloner
- University of Southern California, The Heart Institute, Good Samaritan Hospital, Division of Cardiology, 1225 Wilshire Boulevard, Los Angeles, CA 90017-2395, USA
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Salom JB, Castelló-Ruiz M, Burguete MC, Guzmán C, Jover-Mengual T, Torregrosa G, Jover R, Lizasoain I, Alborch E. Role of K+ and Ca2+ fluxes in the cerebroarterial vasoactive effects of sildenafil. Eur J Pharmacol 2007; 581:138-47. [PMID: 18155692 DOI: 10.1016/j.ejphar.2007.11.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2007] [Revised: 11/05/2007] [Accepted: 11/15/2007] [Indexed: 11/28/2022]
Abstract
The aim of this study was to assess the role of K(+) and Ca(2+) fluxes in the cerebroarterial vasoactive effects of the phosphodiesterase-5 inhibitor sildenafil. We used isolated rabbit basilar arteries to assess the effects of extracellular K(+) raising on sildenafil-induced vasodilatation, and studied the pharmacological interaction of sildenafil with selective modulators of membrane K(+) and Ca(2+) channels. Expression of Kv1 subunits of K(+) channels was assessed at messenger and protein levels. Parallel experiments were carried out with zaprinast for comparison. Sildenafil (10 nM-0.1 mM) induced concentration-dependent relaxation of endothelin-1 (10 nM)-precontracted arteries, which was partially inhibited by depolarization with KCl (50 mM), 3 mM tetraethylammonium (non-selective K(+) channel blocker) or 1 mM aminopyridine (inhibitor of K(v) channels), but not by 1 microM glibenclamide (inhibitor of K(ATP) channels) or 50 nM iberiotoxin (inhibitor of K(Ca) channels). Arterial smooth muscle expressed messengers for Kv1.2, Kv1.3, Kv1.4, Kv1.5 and Kv1.6, and proteins of Kv1.1, Kv1.2 and Kv1.4. CaCl(2) (10 microM- 10 mM) induced concentration-dependent contraction in Ca(2+)-free, depolarizing (50 mM KCl) medium. Sildenafil (0.1-100 microM) produced reversible concentration-dependent inhibition of the response to CaCl(2), which was completely abolished by the highest sildenafil concentration. By contrast, only 100 microM zaprinast inhibited the response to CaCl(2). The L-type Ca(2+) channel activator Bay K 8644 (0.1 nM-1 microM) induced concentration-dependent potentiation of the response to CaCl(2) inhibited by 100 microM sildenafil. Moreover, Bay K 8644 (0.1 nM-1 microM) induced concentration-dependent contraction in slightly depolarizing (15 mM) medium, which was inhibited to the same extent and in a concentration-dependent way by sildenafil (0.1-100 microM) and zaprinast (1 or 100 microM). These results show that sildenafil relaxes the rabbit basilar artery by increasing K(+) efflux through K(v) channels, which in turn may affect Ca(2+) signalling. Expression of Kv1 subunits involved in this pharmacological effect occurs at the messenger and, in some cases, at the protein level. In addition to this phosphodiesterase-5-related effect, sildenafil and zaprinast inhibit cerebroarterial vasoconstriction at least in part by directly blocking L-type Ca(2+) channels, although a decrease in the sensitivity of the contractile apparatus to Ca(2+) can not be discarded.
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Affiliation(s)
- Juan B Salom
- Centro de Investigación, Hospital Universitario La Fe, Valencia, Spain.
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