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Cayetano-Alcaraz AA, Tharakan T, Chen R, Sofikitis N, Minhas S. The management of erectile dysfunction in men with diabetes mellitus unresponsive to phosphodiesterase type 5 inhibitors. Andrology 2023; 11:257-269. [PMID: 35929992 DOI: 10.1111/andr.13257] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 07/29/2022] [Indexed: 01/18/2023]
Abstract
INTRODUCTION Erectile dysfunction is associated with diabetes mellitus with an estimated prevalence of 52.5% in the diabetic population. The first-line therapy for erectile dysfunction is phosphodiesterase type 5 inhibitors, but data suggest that diabetic men may be less responsive than non-diabetic men. Thus, other treatments, including intracavernosal injections, intraurethral prostaglandin, vacuum erection devices and penile prosthetic surgery, should be considered in management of diabetic men with erectile dysfunction refractory to phosphodiesterase type 5 inhibitors. Furthermore, combination therapy of phosphodiesterase type 5 inhibitors and other oral treatments such as arginine or l-carnitine may have synergistic effects resulting in better outcomes. In addition, there are novel therapies such as low-intensity shockwave therapy and stem-cell therapy, which may also be effective in targeted treatment modalities. Furthermore, studies suggest that erectile dysfunction can be improved by targeting concurrent comorbidities or metabolic diseases such as depression, hypertension, hypogonadism, and dyslipidaemia. We present an evidence-based narrative review focusing on the management of erectile dysfunction in diabetic men who have not responded to phosphodiesterase type 5 inhibitors. CONCLUSIONS Both clinicians and patients should be aware of the different management options in diabetic patients who have not responded to phosphodiesterase type 5 inhibitors.
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Affiliation(s)
| | - Tharu Tharakan
- Department of Urology, Imperial College Healthcare NHS Trust, Charing Cross Hospital, London, UK
| | - Runzhi Chen
- Faculty of Medicine, Imperial College London, London, UK
| | - Nikolaos Sofikitis
- Department of Urology, University of Ioannina School of Medicine, Ioannina, Greece
| | - Suks Minhas
- Department of Urology, Imperial College Healthcare NHS Trust, Charing Cross Hospital, London, UK
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Pierre CJ, Azeez TA, Rossetti ML, Gordon BS, La Favor JD. Long-term administration of resveratrol and MitoQ stimulates cavernosum antioxidant gene expression in a mouse castration model of erectile dysfunction. Life Sci 2022; 310:121082. [PMID: 36252696 PMCID: PMC9746260 DOI: 10.1016/j.lfs.2022.121082] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 10/01/2022] [Accepted: 10/11/2022] [Indexed: 11/09/2022]
Abstract
AIMS Erectile dysfunction is a common complication within many pathological conditions associated with low testosterone. Testosterone deficiency increases oxidative stress in the penile tissue that contributes to endothelial dysfunction and subsequent erectile dysfunction. Current therapies do not ameliorate oxidative stress so targeting oxidative stress may improve erectile dysfunction. Resveratrol and MitoQ are two prospective drugs that have antioxidant-like properties and may be useful to improve erectile dysfunction induced by androgen deprivation. MATERIALS AND METHODS We castrated 12-week-old male C57BL/6 mice and performed an eight-week intervention with oral delivery of resveratrol or MitoQ at low and high doses. We assessed vascular reactivity of the corpus cavernosum and internal pudendal arteries (IPA) through dose-dependent responses to vasodilatory, vasocontractile, and neurogenic stimuli in a myograph system. We performed qRT-PCR to measure expression changes of 18 antioxidant genes in the corpus cavernosum. KEY FINDINGS Castration significantly impaired erectile function via impaired endothelial-dependent and-independent relaxation, and increased constriction of the corpus cavernosum, and induced severe endothelial dysfunction of the IPA. Castration decreased expression of 8 of the antioxidant genes investigated. Resveratrol and MitoQ were ineffective in reversing the effects of androgen deprivation on vascular reactivity, however high-dose resveratrol treatment upregulated several key antioxidant genes, including Cat, Sod1, Gstm1, and Prdx3. SIGNIFICANCE Our findings suggest that oral resveratrol and MitoQ treatment may provide protection to the corpus cavernosum under androgen deprived conditions by stimulating endogenous antioxidant systems. However, they may need to be paired with vasoactive drugs to reverse erectile dysfunction under androgen deprived conditions.
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Affiliation(s)
- Clifford J Pierre
- Department of Nutrition and Integrative Physiology, College of Health and Human Sciences, Florida State University, Tallahassee, FL, United States
| | - Tooyib A Azeez
- Department of Nutrition and Integrative Physiology, College of Health and Human Sciences, Florida State University, Tallahassee, FL, United States
| | - Michael L Rossetti
- Department of Nutrition and Integrative Physiology, College of Health and Human Sciences, Florida State University, Tallahassee, FL, United States
| | - Bradley S Gordon
- Department of Nutrition and Integrative Physiology, College of Health and Human Sciences, Florida State University, Tallahassee, FL, United States
| | - Justin D La Favor
- Department of Nutrition and Integrative Physiology, College of Health and Human Sciences, Florida State University, Tallahassee, FL, United States.
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Mykoniatis I, Pyrgidis N, Sokolakis I, Ouranidis A, Sountoulides P, Haidich AB, van Renterghem K, Hatzichristodoulou G, Hatzichristou D. Assessment of Combination Therapies vs Monotherapy for Erectile Dysfunction: A Systematic Review and Meta-analysis. JAMA Netw Open 2021; 4:e2036337. [PMID: 33599772 PMCID: PMC7893498 DOI: 10.1001/jamanetworkopen.2020.36337] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
IMPORTANCE Combining 2 first-line treatments for erectile dysfunction (ED) or initiating other modalities in addition to a first-line therapy may produce beneficial outcomes. OBJECTIVE To assess whether different ED combination therapies were associated with improved outcomes compared with first-line ED monotherapy in various subgroups of patients with ED. DATA SOURCES Studies were identified through a systematic search in MEDLINE, Cochrane Library, and Scopus from inception of these databases to October 10, 2020. STUDY SELECTION Randomized clinical trials or prospective interventional studies of the outcomes of combination therapy vs recommended monotherapy in men with ED were identified. Only comparative human studies, which evaluated the change from baseline of self-reported erectile function using validated questionnaires, that were published in any language were included. DATA EXTRACTION AND SYNTHESIS Data extraction and synthesis were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline. MAIN OUTCOMES AND MEASURES A meta-analysis was conducted that included randomized clinical trials that compared outcomes of combination therapy with phosphodiesterase type 5 (PDE5) inhibitors plus another agent vs PDE5 inhibitor monotherapy. Separate analyses were performed for the mean International Index of Erectile Function (IIEF) score change from baseline and the number of adverse events (AEs) by different treatment modalities and subgroups of patients. RESULTS A total of 44 studies included 3853 men with a mean (SD) age of 55.8 (11.9) years. Combination therapy compared with monotherapy was associated with a mean IIEF score improvement of 1.76 points (95% CI, 1.27-2.24; I2 = 77%; 95% PI, -0.56 to 4.08). Adding daily tadalafil, low-intensity shockwave therapy, vacuum erectile device, folic acid, metformin hydrochloride, or angiotensin-converting enzyme inhibitors was associated with a significant IIEF score improvement, but each measure was based on only 1 study. Specifically, the weighted mean difference (WMD) in IIEF score was 1.70 (95% CI, 0.79-2.61) for the addition of daily tadalafil, 3.50 (95% CI, 0.22-6.78) for the addition of low-intensity shockwave therapy, 8.40 (95% CI, 4.90-11.90) for the addition of a vacuum erectile device, 3.46 (95% CI, 2.16-4.76) for the addition of folic acid, 4.90 (95% CI, 2.82-6.98) for the addition of metformin hydrochloride and 2.07 (95% CI, 1.37-2.77) for the addition of angiotensin-converting enzyme inhibitors. The addition of α-blockers to PDE5 inhibitors was not associated with improvement in IIEF score (WMD, 0.80; 95% CI, -0.06 to 1.65; I2 = 72%). Compared with monotherapy, combination therapy was associated with improved IIEF score in patients with hypogonadism (WMD, 1.61; 95% CI, 0.99-2.23; I2 = 0%), monotherapy-resistant ED (WMD, 4.38; 95% CI, 2.37-6.40; I2 = 52%), or prostatectomy-induced ED (WMD, 5.47; 95% CI, 3.11-7.83; I2 = 53%). The treatment-related AEs did not differ between combination therapy and monotherapy (odds ratio, 1.10; 95% CI, 0.66-1.85; I2 = 78%). Despite multiple subgroup and sensitivity analyses, the levels of heterogeneity remained high. CONCLUSIONS AND RELEVANCE This study found that combination therapy of PDE5 inhibitors and antioxidants was associated with improved ED without increasing the AEs. Treatment with PDE5 inhibitors and daily tadalafil, shockwaves, or a vacuum device was associated with additional improvement, but this result was based on limited data. These findings suggest that combination therapy is safe, associated with improved outcomes, and should be considered as a first-line therapy for refractory, complex, or difficult-to-treat cases of ED.
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Affiliation(s)
- Ioannis Mykoniatis
- Department of Urology, Faculty of Medicine, Aristotle University of Thessaloniki School of Health Sciences, Thessaloniki, Greece
| | - Nikolaos Pyrgidis
- Department of Urology, Faculty of Medicine, Aristotle University of Thessaloniki School of Health Sciences, Thessaloniki, Greece
- Department of Urology, Martha-Maria Hospital Nuremberg, Nuremberg, Germany
| | - Ioannis Sokolakis
- Department of Urology, Martha-Maria Hospital Nuremberg, Nuremberg, Germany
| | - Andreas Ouranidis
- Department of Pharmaceutical Technology, Aristotle University of Thessaloniki, Thessaloniki, Greece
- Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Petros Sountoulides
- Department of Urology, Faculty of Medicine, Aristotle University of Thessaloniki School of Health Sciences, Thessaloniki, Greece
| | - Anna-Bettina Haidich
- Department of Hygiene, Social-Preventive Medicine & Medical Statistics, Aristotle University of Thessaloniki Medical School, University Campus, Thessaloniki, Greece
| | - Koenraad van Renterghem
- Department of Urology, Jessa Hospital, Hasselt University, Hasselt, Belgium
- Department of Urology, University Hospitals Leuven, Leuven, Belgium
| | | | - Dimitrios Hatzichristou
- Department of Urology, Faculty of Medicine, Aristotle University of Thessaloniki School of Health Sciences, Thessaloniki, Greece
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Sheweita SA, Meftah AA, Sheweita MS, Balbaa ME. Erectile dysfunction drugs altered the activities of antioxidant enzymes, oxidative stress and the protein expressions of some cytochrome P450 isozymes involved in the steroidogenesis of steroid hormones. PLoS One 2020; 15:e0241509. [PMID: 33166302 PMCID: PMC7652355 DOI: 10.1371/journal.pone.0241509] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 10/15/2020] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVES Infertility is a global health problem with about 15 percent of couples involved. About half of the cases of infertility are related to male-related factors. A major cause of infertility in men is oxidative stress, which refers to an imbalance between levels of reactive oxygen species (ROS) and antioxidants. Erectile dysfunction drugs (EDD), known as phosphodiesterase inhibitors (PDEIs), have been used for the treatment of ED. It has been shown that oxidative stress plays an important role in the progression of erectile dysfunction. Oxidative stress can be alleviated or decreased by non-antioxidants and antioxidant enzymes. The present study was undertaken to determine if these compounds could have a role in the incidence of infertility, especially after long-term use. Therefore, the present study aims to investigate the effect of EDD on the activities of antioxidant enzymes, free radical levels as well as the protein expression of different cytochrome P450 isozymes involved in the steroidogenesis of different hormones. In addition, the activity of both 17β-hydroxysteroid dehydrogenase and 17-ketosteroid reductase were assayed. The architectures of both livers and testes cells were investigated under the influence of EDD. METHODS A daily dose of Sildenafil (1.48 mg/kg), Tadalafil (0.285 mg/kg) and Vardenafil (0.285 mg/kg) were administered orally to male rabbits for 12 week. Western immunoblotting, ELISA, spectrophotometric and histopathological techniques were used in this study. RESULTS The present study showed that Sildenafil, Vardenafil, and Tadalafil treatments significantly decreased the levels of glutathione and free radicals in both livers and testes of rabbits. Also, Vardenafil and Sildenafil induced the activity of superoxide dismutase and catalase whereas, glutathione S-transferase, glutathione reductase, and glutathione peroxidase activities inhibited in livers of rabbits. The protein expression of cytochrome P450 isozymes (CYP 11A1, 21A2, and 19C) which are involved in the steroidogenesis was markedly changed in both livers and testes of rabbits after their treatments for 12 weeks. After the treatment of rabbits with these medication, the protein expression of CYP11A1 was slightly down-regulated in both livers and testes except Sildenafil up-regulated such protein expression. In addition, the protein expressions of CYP11A1 and CYP 19C in both livers and testes were down-regulated after treatment of rabbits with Sildenafil, Vardenafil, and Tadalafil for 12 weeks. Also, these drugs inhibited the activity of both 17β-hydroxysteroid dehydrogenase and 17-ketosteroid reductase in testes of rabbits. Moreover, Sildenafil, Vardenafil, and Tadalafil-treated rabbits showed a decrease in spermatocytes and the number of sperms in the testes. CONCLUSIONS It is concluded that ED drugs induced the activities of both SOD and catalase which consequently decreased MDA level. Decrement in MDA levels and oxidative stress could therefore sustain the erection for a long period of time. On the other hand, it is not advised to use these drugs for a long-term since the protein expressions of CYP isozymes involved in steroidogenesis as well as the numbers of spermatocytes in testes were decreased.
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Affiliation(s)
- Salah A. Sheweita
- Department of Clinical Biochemistry, Faculty of Medicine, King Khalid University, Abha, Kingdom of Saudi Arabia
- Department of Biotechnology, Alexandria University, Alexandria, Egypt
- * E-mail:
| | - Amal A. Meftah
- Department of Biotechnology, Alexandria University, Alexandria, Egypt
| | - Mohamed S. Sheweita
- Department of Urology, Alexandria Main Hospital, Alexandria University, Alexandria, Egypt
| | - Mahmoud E. Balbaa
- Department of Biochemistry, Faculty of Science, Alexandria University, Alexandria, Egypt
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Alcalase-hydrolyzed oyster (Crassostrea rivularis) meat enhances antioxidant and aphrodisiac activities in normal male mice. Food Res Int 2019; 120:178-187. [DOI: 10.1016/j.foodres.2019.02.033] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 02/18/2019] [Accepted: 02/19/2019] [Indexed: 01/06/2023]
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Haripriya VM, Dhamotharan K, Shukla SK, Suvekbala V, Ragupathy L, Kumaran A. Aphrodisiac properties of hydro-alcoholic extract of Cassia auriculata
flower in male rats. Andrologia 2018; 51:e13180. [DOI: 10.1111/and.13180] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 08/31/2018] [Accepted: 09/13/2018] [Indexed: 01/25/2023] Open
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Cancer Induced Infertility and the Role of L-Carnitine: A Review for Possible Future Clinical Applications. INTERNATIONAL JOURNAL OF CANCER MANAGEMENT 2017. [DOI: 10.5812/ijcm.9857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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8
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Priviero FBM, Toque HAF, Nunes KP, Priolli DG, Teixeira CE, Webb RC. Impaired Corpus Cavernosum Relaxation Is Accompanied by Increased Oxidative Stress and Up-Regulation of the Rho-Kinase Pathway in Diabetic (Db/Db) Mice. PLoS One 2016; 11:e0156030. [PMID: 27227463 PMCID: PMC4882003 DOI: 10.1371/journal.pone.0156030] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 05/09/2016] [Indexed: 11/30/2022] Open
Abstract
Basal release of nitric oxide from endothelial cells modulates contractile activity in the corpus cavernosum via inhibition of the RhoA/Rho-kinase signaling pathway. We aimed to investigate nitric oxide bioavailability, oxidative stress and the Rho-kinase pathway in the relaxation of the corpus cavernosum of an obese and diabetic model of mice (db/db mice). We hypothesized that in db/db mice impaired relaxation induced by Rho-kinase inhibitor is accompanied by diminished NO bioavailability, increased oxidative stress and upregulation of the RhoA/Rho-kinase signalling pathway. Cavernosal strips from male lean and non-diabetic db/+ and db/db mice were mounted in myographs and isometric force in response to Rho-kinase inhibitor Y-27632 was recorded. Enzyme activity and protein expression of oxidative stress markers and key molecules of the RhoA/Rho-kinase pathway were analyzed. The Rho-kinase inhibitor Y-27632 concentration-dependently caused corpus cavernosum relaxation and inhibited cavernosal contractions. Nonetheless, a rightward shift in the curves obtained in corpus cavernosum of db/db mice was observed. Compared to db/+, this strain presented increased active RhoA, higher MYPT-1 phosphorylation stimulated by phenylephrine, and increased expression of ROKα and Rho-GEFs. Further, we observed normal expression of endothelial and neuronal NOS in corpus cavernosum of db/db mice. However, nitrate/nitrate (NOx) levels were diminished, suggesting decreased NO bioavailability. We measured the oxidant status and observed increased lipid peroxidation, with decreased SOD activity and expression. In conclusion, our data demonstrate that in db/db mice, upregulation of the RhoA/Rho-kinase signalling pathway was accompanied by decreased NO bioavailability and increased oxidative stress contributing to impaired relaxation of the corpus cavermosum of db/db mice.
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Affiliation(s)
- Fernanda B. M. Priviero
- Laboratory of Multidisciplinary Research, Universidade São Francisco, Bragança Paulista, São Paulo, Brazil
- * E-mail:
| | - Haroldo A. F. Toque
- Department of Pharmacology and Toxicology, Augusta University, Augusta, Georgia, United States of America
| | - Kenia Pedrosa Nunes
- Department of Biological Sciences, Florida Institute of Technology, Melbourne, Florida, United States of America
| | - Denise G. Priolli
- Laboratory of Multidisciplinary Research, Universidade São Francisco, Bragança Paulista, São Paulo, Brazil
| | - Cleber E. Teixeira
- Department of Physiology, Augusta University, Augusta, Georgia, United States of America
| | - R. Clinton Webb
- Department of Physiology, Augusta University, Augusta, Georgia, United States of America
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Effects of prolonged ingestion of epigallocatechin gallate on diabetes type 1-induced vascular modifications in the erectile tissue of rats. Int J Impot Res 2016; 28:133-8. [PMID: 27169491 DOI: 10.1038/ijir.2016.19] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Revised: 02/26/2016] [Accepted: 04/12/2016] [Indexed: 12/28/2022]
Abstract
Diabetes Mellitus type 1 is a metabolic disease that predisposes to erectile dysfunction, partly owing to structural and molecular changes in the corpus cavernosum (CC) vessels. The aim of this study was to determine the effects of early treatment with the antioxidant epigallocatechin gallate (EGCG) in cavernous diabetes-induced vascular modifications. Diabetes was induced in two groups of young Wistar rats; one group was treated with EGCG for 10 weeks. A reduction in smooth muscle content was observed in the CC of diabetic rats, which was significantly attenuated with EGCG consumption. No differences were observed among groups, neither in the expression of VEGF assayed by western blotting nor in the immunofluorescent labeling of vascular endothelial growth factor (VEGF) and its receptors (VEGFR1 and VEGFR2). VEGFR2 was restricted to the endothelium, whereas VEGF and VEGFR1 co-localized in the smooth muscle layer. With regard to the Angiopoietin/Tie-2 system, no quantitative differences in Angiopoietin 1 were observed among the experimental groups. Ang1 localization was restricted to the smooth muscle layer, and receptor Tie2 and Angiopoietin 2 were both expressed in the endothelium. In brief, our results suggest that EGCG consumption prevented diabetes-induced loss of cavernous smooth muscle but does not affect vascular growth factor expression in young rats.
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Mongioi L, Calogero AE, Vicari E, Condorelli RA, Russo GI, Privitera S, Morgia G, La Vignera S. The role of carnitine in male infertility. Andrology 2016; 4:800-7. [DOI: 10.1111/andr.12191] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 02/26/2016] [Accepted: 03/01/2016] [Indexed: 01/02/2023]
Affiliation(s)
- L. Mongioi
- Department of Clinical and Experimental Medicine; University of Catania; Catania Italy
| | - A. E. Calogero
- Department of Clinical and Experimental Medicine; University of Catania; Catania Italy
| | - E. Vicari
- Department of Clinical and Experimental Medicine; University of Catania; Catania Italy
| | - R. A. Condorelli
- Department of Clinical and Experimental Medicine; University of Catania; Catania Italy
| | - G. I. Russo
- Department of Urology; University of Catania; Catania Italy
| | - S. Privitera
- Department of Urology; University of Catania; Catania Italy
| | - G. Morgia
- Department of Urology; University of Catania; Catania Italy
| | - S. La Vignera
- Department of Clinical and Experimental Medicine; University of Catania; Catania Italy
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Kim JH, Lee HJ, Song YS. Mesenchymal stem cell-based gene therapy for erectile dysfunction. Int J Impot Res 2016; 28:81-7. [PMID: 26888355 DOI: 10.1038/ijir.2016.3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Revised: 10/17/2015] [Accepted: 11/23/2015] [Indexed: 12/12/2022]
Abstract
Despite the overwhelming success of PDE5 inhibitor (PDE5I), the demand for novel pharmacotherapeutic and surgical options for ED continues to rise owing to the increased proportion of elderly individuals in the population, in addition to the growing percentage of ED patients who do not respond to PDE5I. Surgical treatment of ED is associated with many complications, thus warranting the need for nonsurgical therapies. Moreover, none of the above-mentioned treatments essentially corrects, cures or prevents ED. Although gene therapy is a promising option, many challenges and obstacles such as local inflammatory response and random transgene expression, in addition to other safety issues, limit its use at the clinical level. The use of stem cell therapy alone also has many shortcomings. To overcome these inadequacies, many scientists and clinicians are investigating new gene and stem cell therapies.
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Affiliation(s)
- J H Kim
- Department of Urology, Soonchunhyang University Hospital, College of Medicine, Soonchunhyang University, Seoul, Korea
| | - H J Lee
- Biomedical Research Institute, Chung-Ang School of Medicine, Seoul, Korea
| | - Y S Song
- Department of Urology, Soonchunhyang University Hospital, College of Medicine, Soonchunhyang University, Seoul, Korea
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12
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Sheweita S, Salama B, Hassan M. Erectile dysfunction drugs and oxidative stress in the liver of male rats. Toxicol Rep 2015; 2:933-938. [PMID: 28962432 PMCID: PMC5598225 DOI: 10.1016/j.toxrep.2015.06.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 05/29/2015] [Accepted: 06/01/2015] [Indexed: 12/14/2022] Open
Abstract
Erectile dysfunction (ED) affected the lives of more than 300 million men worldwide. Erectile dysfunction drugs (EDD), known as phosphodiesterase inhibitors (PDEIs), have been used for treatment of ED. It has been shown that oxidative stress plays an important role in the progression of erectile dysfunction. Oxidative stress can be alleviated or decreased by antioxidant enzymes. Therefore, the present study aims at investigating the changes in the activity of antioxidant enzymes such as superoxide dismutase, catalase, and glutathione reductase as well as protein expression of glutathione peroxidase and glutathione S-transferase after treatment of male rats with a daily dose of sildenafil (1.48 mg/kg), tadalafil (0.285 mg/kg) and vardenafil (0.285 mg/kg) for three weeks. In addition, levels of reduced glutathione and malondialdyhyde (MDA) were assayed. The present study showed that sildenafil, vardenafil, and tadalafil treatments significantly decreased the levels of glutathione, MDA and the activity of glutathione reductase. In addition, vardenafil and sildenafil increased the activity of superoxide dismutase and catalase. Interestingly, western immunoblotting data showed that vardenafil induced the activity of glutathione peroxidase (GPX) and its protein expression, whereas tadalafil and sildenafil inhibited such enzyme activity and its protein expression. In addition, the protein expression of GST π isozyme was markedly reduced after treatment of rats with sildenafil. It is concluded that ED drugs induced the activities of both SOD and catalase which consequently decreased MDA level. Therefore, decrement in MDA levels could increase nitric oxide–cGMP level which in turn promotes the erection mechanism.
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Key Words
- CAT, catalase
- Catalase
- ED, erectile dysfunction
- EDD, erectile dysfunction drugs
- GPx, glutathione peroxidase
- GR, glutathione reductase
- GSH, glutathione
- GST, glutathione S-transferase
- Glutathione
- Glutathione peroxidase
- Glutathione reductase
- MDA, malondialdyhyde
- Oxidative stress
- PDE-5, phosphodiesterase type-5
- PDEIs, phosphodiesterase inhibitors
- ROS, reactive oxygen species
- SOD, superoxide dismutase
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Affiliation(s)
- Salah Sheweita
- Department of Biotechnology, Institute of Graduate Studies & Research, Alexandria University, Egypt
| | - Basant Salama
- Department of Biotechnology, Institute of Graduate Studies & Research, Alexandria University, Egypt
| | - Mostafa Hassan
- Department of Environmental Studies, Institute of Graduate Studies & Research, Alexandria University, Egypt
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La Vignera S, Condorelli RA, Burgio G, Vicari E, Favilla V, Russo GI, Cimino S, Morgia G, Calogero AE. Functional characterization of platelets in patients with arterial erectile dysfunction. Andrology 2014; 2:709-15. [DOI: 10.1111/j.2047-2927.2014.00255.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2013] [Revised: 05/23/2014] [Accepted: 07/09/2014] [Indexed: 01/31/2023]
Affiliation(s)
- S. La Vignera
- Section of Endocrinology, Andrology and Internal Medicine; Department of Internal Medicine and Systemic Disease; University of Catania; Catania Italy
| | - R. A. Condorelli
- Section of Endocrinology, Andrology and Internal Medicine; Department of Internal Medicine and Systemic Disease; University of Catania; Catania Italy
| | - G. Burgio
- Section of Endocrinology, Andrology and Internal Medicine; Department of Internal Medicine and Systemic Disease; University of Catania; Catania Italy
| | - E. Vicari
- Section of Endocrinology, Andrology and Internal Medicine; Department of Internal Medicine and Systemic Disease; University of Catania; Catania Italy
| | - V. Favilla
- Department of Urology; University of Catania; Catania Italy
| | - G. I. Russo
- Department of Urology; University of Catania; Catania Italy
| | - S. Cimino
- Department of Urology; University of Catania; Catania Italy
| | - G. Morgia
- Department of Urology; University of Catania; Catania Italy
| | - A. E. Calogero
- Section of Endocrinology, Andrology and Internal Medicine; Department of Internal Medicine and Systemic Disease; University of Catania; Catania Italy
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Alga Ecklonia bicyclis, Tribulus terrestris, and glucosamine oligosaccharide improve erectile function, sexual quality of life, and ejaculation function in patients with moderate mild-moderate erectile dysfunction: a prospective, randomized, placebo-controlled, single-blinded study. BIOMED RESEARCH INTERNATIONAL 2014; 2014:121396. [PMID: 25136552 PMCID: PMC4127274 DOI: 10.1155/2014/121396] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 06/01/2014] [Indexed: 12/18/2022]
Abstract
We aimed to evaluate the efficacy of oral therapy with alga Ecklonia bicyclis, Tribulus terrestris, and glucosamine oligosaccharide (Tradamix TX1000) in patients with erectile dysfunction (ED) at 3 months of follow-up. From January 2013 to September 2013, 177 patients diagnosed with mild-moderate ED (IIEF-EF < 26) were enrolled in this multicenter, single-blinded, placebo-controlled study and randomized in Group A (Tradamix, n = 87) and Group B (placebo, n = 90). Penile color Doppler ultrasound measures, IIEF-15 questionnaire, male sexual health questionnaire-ejaculation disorder (MSHQ-EjD), and sexual quality of life (SQoL-M) were collected. We observed significant changes of the IIEF-15 in Group A (mean difference: 11.54; P < 0.05) at 3 months versus Group B (P < 0.05). PSV (P < 0.05), IIEF-intercourse satisfaction (P < 0.05), IIEF-orgasmic function (mean P < 0.05), IIEF-sexual desire (P < 0.05), IIEF-overall satisfaction (P < 0.05), MSHQ-EjD (mean difference: 1.21; P < 0.05), and SQoL-M (mean difference: 10.2; P < 0.05) were significantly changed in Group A versus baseline and Group B. Patients with moderate arterial dysfunction showed significant increase of PSV (P < 0.05), IIEF-EF (P < 0.05), MSHQ-EjD (P < 0.05), and SQoL-M (P < 0.05) in Group A. Therapy with Tradamix improves erectile and ejaculation function and sexual quality of life in patients with mild-moderate ED and in particular for those with moderate arterial dysfunction.
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Bivalacqua TJ, Musicki B, Hsu LL, Berkowitz DE, Champion HC, Burnett AL. Sildenafil citrate-restored eNOS and PDE5 regulation in sickle cell mouse penis prevents priapism via control of oxidative/nitrosative stress. PLoS One 2013; 8:e68028. [PMID: 23844149 PMCID: PMC3699477 DOI: 10.1371/journal.pone.0068028] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 05/23/2013] [Indexed: 11/18/2022] Open
Abstract
Sildenafil citrate revolutionized the practice of sexual medicine upon its federal regulatory agency approval approximately 15 years ago as the prototypical phosphodiesterase type 5 inhibitor indicated for the treatment of male erectile dysfunction. We now provide scientific support for its alternative use in the management of priapism, a clinical disorder of prolonged and uncontrolled penile erection. Sildenafil administered continuously to sickle cell mice, which show a priapism phenotype, reverses oxidative/nitrosative stress effects in the penis, mainly via reversion of uncoupled endothelial nitric oxide synthase to the functional coupled state of the enzyme, which in turn corrects aberrant signaling and function of the nitric oxide/cyclic GMP/protein kinase G/phosphodiesterase type 5 cascade. Priapism tendencies in these mice are reverted partially toward normal neurostimulated erection frequencies and durations after sildenafil treatment in association with normalized cyclic GMP concentration, protein kinase G activity and phosphodiesterase type 5 activity in the penis. Thus, sildenafil exerts pleiotropic effects in the penis that extend to diverse erection disorders.
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Affiliation(s)
- Trinity J. Bivalacqua
- The James Buchanan Brady Urological Institute, Johns Hopkins Medical Institutions, Baltimore, Maryland, United States of America
| | - Biljana Musicki
- The James Buchanan Brady Urological Institute, Johns Hopkins Medical Institutions, Baltimore, Maryland, United States of America
| | - Lewis L. Hsu
- Vascular Medicine Branch, National Heart Lung Blood Institute, National Institutes of Health, Bethesda, Maryland, United States of America
- Department of Pediatrics, University of Illinois, Chicago, Illinois, United States of America
| | - Dan E. Berkowitz
- Department of Anesthesiology and Critical Care Medicine, and Biomedical Engineering, Johns Hopkins Medical Institutions, Baltimore, Maryland, United States of America
| | - Hunter C. Champion
- Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
| | - Arthur L. Burnett
- The James Buchanan Brady Urological Institute, Johns Hopkins Medical Institutions, Baltimore, Maryland, United States of America
- * E-mail:
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Muniz JJ, Lacchini R, Sertório JTC, Jordão AA, Nobre YTDA, Tucci S, Martins ACP, Tanus-Santos JE. Low nitric oxide bioavailability is associated with better responses to sildenafil in patients with erectile dysfunction. Naunyn Schmiedebergs Arch Pharmacol 2013; 386:805-11. [DOI: 10.1007/s00210-013-0882-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2013] [Accepted: 05/08/2013] [Indexed: 12/19/2022]
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Condorelli RA, Calogero AE, Vicari E, Favilla V, Morgia G, Cimino S, La Vignera S. Vascular regenerative therapies for the treatment of erectile dysfunction: current approaches. Andrology 2013; 1:533-40. [DOI: 10.1111/j.2047-2927.2013.00087.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2013] [Revised: 03/01/2013] [Accepted: 03/09/2013] [Indexed: 12/20/2022]
Affiliation(s)
- R. A. Condorelli
- Section of Endocrinology; Andrology and Internal Medicine; Department of Medical and Pediatric Sciences; University of Catania; Catania; Italy
| | - A. E. Calogero
- Section of Endocrinology; Andrology and Internal Medicine; Department of Medical and Pediatric Sciences; University of Catania; Catania; Italy
| | - E. Vicari
- Section of Endocrinology; Andrology and Internal Medicine; Department of Medical and Pediatric Sciences; University of Catania; Catania; Italy
| | - V. Favilla
- Department of Urology; University of Catania; Catania; Italy
| | - G. Morgia
- Department of Urology; University of Catania; Catania; Italy
| | - S. Cimino
- Department of Urology; University of Catania; Catania; Italy
| | - S. La Vignera
- Section of Endocrinology; Andrology and Internal Medicine; Department of Medical and Pediatric Sciences; University of Catania; Catania; Italy
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Condorelli RA, Calogero AE, Favilla V, Morgia G, Johnson EO, Castiglione R, Salemi M, Mongioí L, Nicoletti C, Duca Y, Di Mauro M, Vicari E, La Vignera S. Arterial erectile dysfunction: different severities of endothelial apoptosis between diabetic patients "responders" and "non responders" to sildenafil. Eur J Intern Med 2013; 24:234-40. [PMID: 23357410 DOI: 10.1016/j.ejim.2013.01.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Revised: 12/23/2012] [Accepted: 01/03/2013] [Indexed: 11/30/2022]
Abstract
BACKGROUND The low pharmacological response to phosphodiesterase type 5 inhibitors represents an expression of higher endothelial damage in certain categories of patients with erectile dysfunction and high cardiovascular risk. The present study evaluated this objective in type 2 diabetic patients with erectile dysfunction, classified as "non responders" to Sildenafil. METHODS Eighteen "responder" and twelve "non responder" type 2 diabetic patients were evaluated, relatively to different levels of endothelial damage, through the diagnostic use of a new immunophenotype of circulating endothelial progenitor cells (CD45neg/CD34pos/CD144pos) and endothelial microparticles (CD45neg/CD144pos/Annexin Vpos), recently developed and published by our group. RESULTS "Non responder" patients showed a significant higher severity [8.0±3.0 (International Index of Erectile Function-abbreviated version with 5 questions) vs 14.0±3.0] and duration (10.0±2.0 vs 7.0±2.0 years) of erectile dysfunction, higher level of penile arterial insufficiency (peak systolic velocity=13.0±16.0 vs 28.0±26.0cm/s; acceleration time=153±148 vs 125±128 mm/s) and finally a significant higher level of endothelial apoptosis [0.15±0.13 vs 0.05±.0.03% (serum concentrations of endothelial microparticles)] associated with higher serum concentrations of circulating late immunophenotype of endothelial progenitor cells (0.40±0.35 vs 0.12±.0.10%). CONCLUSIONS The results of this study corroborate the clinical value of the low clinical response to phosphodiesterase type 5 inhibitors in the treatment of erectile dysfunction in the patients with high cardiovascular risk profile, such as diabetics. In addition, the markers used in this study confirm their potential application in clinical practice as useful indicators of endothelial alteration. However, in the future we will have to assess a larger number of patients and for a longer period of observation in order to better understand the causal and temporal relations.
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Affiliation(s)
- Rosita A Condorelli
- Section of Endocrinology, Andrology and Internal Medicine, Department of Medical and Pediatric Sciences, University of Catania, Italy
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Mostafa T, Sabry D, Abdelaal AM, Mostafa I, Taymour M. Cavernous antioxidant effect of green tea, epigallocatechin-3-gallate with/without sildenafil citrate intake in aged diabetic rats. Andrologia 2012; 45:272-7. [PMID: 22928786 DOI: 10.1111/and.12005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/20/2012] [Indexed: 02/05/2023] Open
Abstract
This study aimed to assess the cavernous antioxidant effect of green tea (GT), epigallocatechin-3-gallate (EGCG) with/without sildenafil citrate intake in aged diabetic rats. One hundred and four aged male white albino rat were divided into controls that received ordinary chow, streptozotocin (STZ)-induced aged diabetic rats, STZ-induced diabetic rats on infused green tea, induced diabetic rats on epigallocatechin-3-gallate and STZ-induced diabetic rats on sildenafil citrate added to EGCG. After 8 weeks, dissected cavernous tissues were assessed for gene expression of eNOS, cavernous malondialdehyde (MDA), glutathione peroxidase (GPx), cyclic guanosine monophosphate (cGMP), and serum testosterone (T). STZ-induced diabetic rats on GT demonstrated significant increase in cavernous eNOS, cGMP, GPx and significant decrease in cavernous MDA compared with diabetic rats. Diabetic rats on EGCG demonstrated significant increase in cavernous eNOS, cGMP, GPx and significant decrease in cavernous MDA compared with diabetic rats or diabetic rats on GT. Diabetic rats on EGCG added to sildenafil showed significant increase in cavernous eNOS, cGMP and significant decrease in cavernous MDA compared with other groups. Serum T demonstrated nonsignificant difference between the investigated groups. It is concluded that GT and EGCG have significant cavernous antioxidant effects that are increased if sildenafil is added.
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Affiliation(s)
- T Mostafa
- Department of Andrology and Sexology, Faculty of Medicine, Cairo University, Cairo, Egypt.
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Chen Y, Li XX, Lin HC, Qiu XF, Gao J, Dai YT, Wang R. The effects of long-term administration of tadalafil on STZ-induced diabetic rats with erectile dysfunction via a local antioxidative mechanism. Asian J Androl 2012; 14:616-20. [PMID: 22504870 DOI: 10.1038/aja.2012.22] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Type 5 phosphodiesterase inhibitors (PDE5Is) are well known being effective via the nitric oxide and cyclic guanosine monophosphate (NO-cGMP) pathway and are widely used in the treatment of diabetic erectile dysfunction (ED). However, it is unclear whether other pathways may be involved in the treatment of diabetic ED with PDE5Is. The purpose of this study was to clarify the role of antioxidants in diabetic ED treatment through the long-term administration of PDE5Is. Three groups of Sprague-Dawley rats were utilized: Group N, the normal control; Group D, streptozotocin (STZ)-induced diabetic rats as a control; and Group D+T, STZ-induced diabetic rats who received oral administration of tadalafil for 8 weeks. Erectile function was assessed by intracavernous pressure (ICP) and mean arterial pressure (MAP) during electrical stimulation of the cavernous nerve before euthanasia. The levels of malondialdehyde (MDA), superoxide dismutase (SOD) and mitochondrial membrane potential (MMP) of cavernous tissue were assessed by biochemical analysis. The morphology of mitochondria was observed by electron microscopy. The ICP/MAP ratio was higher in Group D+T than in Group D (P<0.05). The levels of MDA decreased and the activities of SOD increased in Group D+T in comparison with Group D (P<0.05). The mitochondrial membrane potential level of cavernous tissue in diabetic rats was partially recovered by tadalafil treatment for 8 weeks. The morphology changes of mitochondria were also remarkably ameliorated in Group D+T. Collectively, the long-term administration of tadalafil in diabetic rats partially reduced oxidative stress lesions of the penis via a local antioxidative stress pathway. Long-term dosages of tadalafil given once daily beginning soon after the onset of diabetes may aid in preventing rats from developing diabetic ED.
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Affiliation(s)
- Yun Chen
- Department of Urology, the Affiliated Drum Tower Hospital, Nanjing University Medical School, Nanjing 210008, China
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Decaluwé K, Pauwels B, Verpoest S, Van de Voorde J. New Therapeutic Targets for the Treatment of Erectile Dysfunction. J Sex Med 2011; 8:3271-90. [DOI: 10.1111/j.1743-6109.2011.02459.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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22
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Xu M, Tang YQ, Dai DZ, Zheng YF, Cheng YS, Zhang Q, Dai Y. Comparison of sildenafil with strontium fructose diphosphate in improving erectile dysfunction against upregulated cavernosal NADPH oxidase, protein kinase Cε, and endothelin system in diabetic rats. J Pharm Pharmacol 2011; 64:244-51. [DOI: 10.1111/j.2042-7158.2011.01390.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Abstract
Objectives
Phosphodiesterase type 5 inhibitors are potent in relieving erectile dysfunction (ED), however, they are less satisfactory in diabetic patients, probably due to the pro-inflammatory biomarkers caused by diabetes. Therefore, it was interesting to compare the effects of sildenafil with strontium fructose 1,6-diphosphate (FDP-Sr) on cavernosal vascular activity and expressions of pro-inflammatory biomarkers in diabetic rats.
Methods
Male Sprague-Dawley rats were injected with streptozocin (60 mg/kg, i.p.) to develop diabetes. The animals were diabetic for eight weeks with sildenafil (12 mg/kg per day) or FDP-Sr (200 mg/kg per day) being administered for the last four of those eight weeks.
Key findings
Sildenafil was more effective in relieving reduced vascular dilatation (relevant to ED), but less in attenuating over-expressions of NADPH oxidase p22, p47 and p67 subunits, and ETA/BR (endothelin receptor type A and type B) in the diabetic cavernosum. In contrast, FDP-Sr was less effective in improving ED, but more effective in normalizing the abnormal NADPH oxidase and ETA/BR.
Conclusions
The activated NADPH oxidase and upregulated ETAR and ETBR due to diabetic lesions played a minor or moderate role in ED. By offering extra ATP, FPD-Sr suppressed these abnormalities, however, sildenafil did not. A combined therapy of sildenafil with FDP-Sr may be more effective in relieving ED in diabetic patients through normalizing pro-inflammatory cytokines and improving the nitric oxide/cGMP pathway in the cavernosum.
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Affiliation(s)
- Ming Xu
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - Yi-Qun Tang
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - De-Zai Dai
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - Yu-Feng Zheng
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - Yu-Si Cheng
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - Qi Zhang
- College of Life Science and Pharmaceutical Engineering, Nanjing University of Technology, Nanjing, China
| | - Yin Dai
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China
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Francis SH, Corbin JD. PDE5 inhibitors: targeting erectile dysfunction in diabetics. Curr Opin Pharmacol 2011; 11:683-8. [PMID: 21924956 DOI: 10.1016/j.coph.2011.08.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2011] [Accepted: 08/24/2011] [Indexed: 12/17/2022]
Abstract
Erectile dysfunction (ED) is strongly linked to cardiovascular disease (CVD), especially in diabetics. ED is associated with deleterious changes in the overall vasculature and is recognized as an indicator of higher risk for adverse cardiovascular events. Endothelial dysfunction, vascular smooth muscle changes and increased fibrosis are indicated as major players in both ED and CVD. ED in diabetics is more refractory to acute treatment with phosphodiesterase-5 (PDE5) inhibitors (Viagra, Cialis, Levitra, Zydena) than in non-diabetics, but recent studies indicate that chronic administration of these drugs improves endothelial function, preserves vascular smooth muscle and decreases fibrotic changes. Use of PDE5 inhibitors in pre-diabetic and diabetic men may protect cardiovascular health, including vascular function in penile tissues.
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Affiliation(s)
- Sharron H Francis
- Department Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232-0615, United States.
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Ferrini MG, Moon J, Rivera S, Rajfer J, Gonzalez-Cadavid NF. Amelioration of diabetes-induced cavernosal fibrosis by antioxidant and anti-transforming growth factor-β1 therapies in inducible nitric oxide synthase-deficient mice. BJU Int 2011; 109:586-93. [PMID: 21851542 DOI: 10.1111/j.1464-410x.2011.10397.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
OBJECTIVE • To investigate whether sustained long-term separate treatments of diabetic inducible nitric oxide synthase knockout (iNOSKo) mice with allopurinol, an antioxidant inhibiting xanthine oxidoreductase, decorin, a transforming growth factor-β1 (TGFβ1) -binding antagonist, and molsidomine, a long-life nitric oxide donor, prevent the processes of diabetes-induced cavernosal fibrosis. MATERIALS AND METHODS • Eight week old male iNOS knock out (iNOSKo) mice were made diabetic by injecting 150 mg/kg B.W Streptozotocin (1P) with were either left untreated or treated with the oral antioxidant allopurinol (40 mg/kg/day), or decoin (50 mg, 1P, twice), as an anti-TGFβ1 agent (n = 8/group). • Glycemia and oxidative stress markers were determined in blood and urine. • Paraffin-embedded tissue sections from the penile shaft were subjected to Masson trichrome staining for the smooth muscle (smc)/collagen ratio, and imunostaining for smc content, profibrotic factors, oxidative stress, cell replication and cell death markers followed by quantitative image analysis. RESULTS • Eight-week treatment with either allopurinol or decorin counteracted the decrease in smooth muscle cells and the increase in apoptosis and local oxidative stress within the corpora tissue. • Decorin but not allopurinol increased the smooth muscle cell/collagen ratio, whereas allopurinol but not decorin inhibited systemic oxidative stress. • Molsidomine was effective in reducing both local and systemic oxidative stress, but did not prevent corporal fibrosis. CONCLUSION • Both allopurinol and decorin appear as promising approaches either as a single or a combined pharmacological modality for protecting the diabetic corpora from undergoing apoptosis and fibrosis although their functional effects still need to be defined.
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Affiliation(s)
- Monica G Ferrini
- Department of Internal Medicine, Charles R. Drew University Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
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Nunes KP, Cordeiro MN, Richardson M, Borges MN, Diniz SOF, Cardoso VN, Tostes R, De Lima ME, Webb RC, Leite R. Nitric oxide-induced vasorelaxation in response to PnTx2-6 toxin from Phoneutria nigriventer spider in rat cavernosal tissue. J Sex Med 2010; 7:3879-88. [PMID: 20722794 DOI: 10.1111/j.1743-6109.2010.01978.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Priapism is one of several symptoms observed in accidental bites by the spider Phoneutria nigriventer. The venom of this spider is comprised of many toxins, and the majority has been shown to affect excitable ion channels, mainly sodium (Na(+) ) channels. It has been demonstrated that PnTx2-6, a peptide extracted from the venom of P. nigriventer, causes erection in anesthetized rats and mice. AIM We investigated the mechanism by which PnTx2-6 evokes relaxation in rat corpus cavernosum. MAIN OUTCOME MEASURES PnTx2-6 toxin potentiates nitric oxide (NO)-dependent cavernosal relaxation. METHODS Rat cavernosal strips were incubated with bretylium (3 × 10(-5) M) and contracted with phenylephrine (PE; 10(-5) M). Relaxation responses were evoked by electrical field stimulation (EFS) or sodium nitroprusside (SNP) before and after 4 minutes of incubation with PnTx2-6 (10(-8) M). The effect of PnTx2-6 on relaxation induced by EFS was also tested in the presence of atropine (10(-6) M), a muscarinic receptor antagonist, N-type Ca(2+) channel blockers (ω-conotoxin GVIA, 10(-6) M) and sildenafil (3 × 10(-8) M). Technetium99m radiolabeled PnTx2-6 subcutaneous injection was administrated in the penis. RESULTS Whereas relaxation induced by SNP was not affected by PnTx2-6, EFS-induced relaxation was significantly potentiated by this toxin as well as PnTx2-6 plus SNP. This potentiating effect was further increased by sildenafil, not altered by atropine, however was completely blocked by the N-type Ca(2+) channels. High concentrated levels of radiolabeled PnTx2-6 was specifically found in the cavernosum tissue, suggesting PnTx2-6 is an important toxin responsible for P. nigriventer spider accident-induced priapism. CONCLUSION We show that PnTx2-6 slows Na(+) channels inactivation in nitrergic neurons, allowing Ca(2+) influx to facilitate NO/cGMP signalling, which promotes increased NO production. In addition, this relaxation effect is independent of phosphodiesterase enzyme type 5 inhibition. Our data displays PnTx2-6 as possible pharmacological tool to study alternative treatments for erectile dysfunction.
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Affiliation(s)
- Kenia P Nunes
- Biological Science Institute, Belo Horizonte, MG, Brazil.
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