Cardioprotector effect of phosphodiesterase 5 inhibitors in experimental model for diabetes mellitus / Efeito cardioprotetor dos inibidores da fosfodiesterase 5 em modelo de diabetes mellitus experimental

Diabetes mellitus (DM) is considered a 21st century pandemic and is often associated with cardiovascular disease (CVD). The aim of this integrative review was to analyze the cardioprotective effects of phosdodiesterase-5 (PDE5i) inhibitors in experimental diabetes models. The articles were selected from the PubMed, SciELO and LILACS databases from 2014 to 2019. The following descriptors were used in combination with the Boolean operators: Diabetes mellitus experimental AND Phosphodiesterase 5 inhibitors; Diabetic cardiomyopathies AND Phosphodiesterase 5 inhibitors. An initial sample of 155 articles was obtained, of which six met the criteria for the synthesis of the review. The studies analyzed showed that treatment with PDE5i in experimental models, resulted in positive effects on cardiac function and metabolic parameters. Similar results have also been seen in humans. The reduction in cardiac hypertrophy, apoptosis of cardiomyocytes, pro-inflammatory factors and oxidative stress and the modulation of transcription factors involved in diabetes homeostasis, were prevalent among studies. The mechanisms of action involved in cardioprotection have not yet been fully elucidated, however the restoration of the activated cyclic guanosine monofate (cGMP) pathway by soluble guanylate cyclase (sGC) via nitric oxide (NO) was a common mechanism among the studies.

O Diabetes mellitus (DM) é considerado uma pandemia do século XXI e está frequentemente associado às doenças cardiovasculares (DCVs). O objetivo desta revisão integrativa foi analisar os efeitos cardioprotetores de inibidores da fosdodiesterase 5 (PDE5i) em modelos de diabetes experimental. Os artigos foram selecionados nas bases de dados PubMed, SciElo e LILACS no período de 2014 a 2019. Foram utilizados os seguintes descritores combinados com os operadores booleanos: Diabetes mellitus experimental AND Phosphodiesterase 5 inhibitors; Diabetic cardiomyopathies AND Phosphodiesterase 5 inhibitors. Foi obtida uma amostra inicial de 155 artigos, dos quais seis se enquadraram nos critérios para a síntese da revisão. Os estudos analisados evidenciaram que o tratamento com os PDEi5 em modelos experimentais, resultou em efeitos positivos sobre a função cardíaca e parâmetros metabólicos. Resultados semelhantes também foram observados em humanos. A redução da hipertrofia cardíaca, apoptose de cardiomiócitos, fatores pró-inflamatórios e estresse oxidativo e a modulação de fatores de transcrição envolvidos na homeostasia do diabetes, foram achados prevalentes entre os estudos. Os mecanismos de ação envolvidos na cardioproteção ainda não foram totalmente elucidados, contudo a restauração da via da guanosina monofato cíclica ativada (GMPc) pela Guanilato ciclase solúvel (GCs) via Óxido Nítrico (NO) foi um mecanismo comum entre os estudos.

Resultados Clínicos e Hemodinâmicos de Longo Prazo após o Transplante de Coração em Pacientes Pré-Tratados com Sildenafil / Long-Term Clinical and Hemodynamic Outcomes after Heart Transplantation in Patients Pre-Treated with Sildenafil

Resumo Fundamento A resistência vascular pulmonar elevada ainda é um grande problema na seleção de candidatos ao transplante cardíaco. Objetivo Nosso objetivo foi avaliar o efeito da administração de sildenafila pré-transplante cardíaco em pacientes com hipertensão pulmonar fixa. Métodos O estudo retrospectivo, de centro único, incluiu 300 candidatos a transplante cardíaco consecutivos tratados entre 2003 e 2013. Destes, 95 pacientes tinham hipertensão pulmonar fixa e, dentre eles, 30 pacientes foram tratados com sildenafila e acabaram passando pelo transplante, formando o Grupo A. O Grupo B incluiu 205 pacientes sem hipertensão pulmonar que passaram pelo transplante cardíaco. A hemodinâmica pulmonar foi avaliada antes do transplante, 1 semana e 1 ano após o transplante. A taxa de sobrevivência foi comparada entre os grupos. Neste estudo, um P valor < 0,05 foi considerado estatisticamente significativo. Resultados Após o tratamento com sildenafila, mas antes do TxC, a RVP (-39%) e a PAPs (-10%) diminuíram significativamente. A PAPs diminuiu após o TxC em ambos os grupos, mas permaneceu significativamente alta no grupo A em relação ao grupo B (40,3 ± 8,0 mmHg versus 36,5 ± 11,5 mmHg, P=0,022). Um ano após o TxC, a PAPs era 32,4 ± 6,3 mmHg no Grupo A versus 30,5 ± 8,2 mmHg no Grupo B (P=0,274). O índice de sobrevivência após o TxC 30 dias (97% no grupo A versus 96% no grupo B), 6 meses (87% versus 93%) e um ano (80% versus 91%) após o TxC não foi estatisticamente significativo (Log-rank P=0,063). Depois do primeiro ano, o índice de mortalidade era similar entre os dois grupos (sobrevivência condicional após 1 ano, Log-rank p=0,321). Conclusão Nos pacientes com HP pré-tratados com sildenafila, a hemodinâmica pós-operatória inicial e o prognóstico são numericamente piores em pacientes sem HP, mas depois de 1 ano, a mortalidade em médio e longo prazo são semelhantes. (Arq Bras Cardiol. 2021; 116(2):219-226)

Abstract Background Elevated pulmonary vascular resistance remains a major problem for heart transplant (HT) candidate selection. Objective This study sought at assess the effect of pre-HT sildenafil administration in patients with fixed pulmonary hypertension. Methods This retrospective, single-center study included 300 consecutive, HT candidates treated between 2003 and 2013, in which 95 patients had fixed PH, and of these, 30 patients were treated with sildenafil and eventually received a transplant, forming Group A. Group B included 205 patients without PH who underwent HT. Pulmonary hemodynamics were evaluated before HT, as well as 1 week after and 1 year after HT. Survival was compared between the groups. In this study, a p value < 0.05 was considered statistically significant. Results After treatment with sildenafil but before HT, PVR (-39%) and sPAP (-10%) decreased significantly. sPAP decreased after HT in both groups, but it remained significantly higher in group A vs. group B (40.3 ± 8.0 mmHg vs 36.5 ± 11.5 mmHg, p=0.022). One year after HT, sPAP was 32.4 ± 6.3 mmHg in group A vs 30.5 ± 8.2 mmHg in group B (p=0.274). The survival rate after HT at 30 days (97% in group A versus 96% in group B), at 6 months (87% versus 93%) and at one year (80% vs 91%) were not statistically significant (Log-rank p=0.063). After this first year, the attrition rate was similar among both groups (conditional survival after 1 year, Log-rank p=0.321). Conclusion In patients with severe PH pre-treated with sildenafil, early post-operative hemodynamics and prognosis are numerically worse than in patients without PH, but after 1 year, the medium to long-term mortality proved to be similar. (Arq Bras Cardiol. 2021; 116(2):219-226)

Help-seeking patterns and funding strategies in patients with pulmonary arterial hypertension on phosphodiesterase-5 inhibitors: an orphan disease with effective but costly treatment

INTRODUCTION@#Pulmonary arterial hypertension (PAH) is associated with high medical and pharmaceutical costs. Phosphodiesterase type 5 (PDE5) inhibitors have been found to be beneficial but costly. They are not subsidised in Singapore except via the Medication Assistance Fund (MAF) Plus scheme. In this study, we described the help-seeking behaviour of patients and funding strategies for Singaporean patients on PDE5 inhibitors in our registry.@*METHODS@#We consecutively recruited all patients with PAH who presented to our pulmonary hypertension specialty centre between 1 January 2003 and 29 December 2016. Singaporean patients on PDE5 inhibitors were included. Data recorded and analysed for this study included baseline demographics, whether the patients received MAF Plus funding, percentage of funding, and any additional source of subsidies.@*RESULTS@#114 (77.0%) of 148 patients in the registry were Singapore citizens on PDE5 inhibitors. 75 (65.8%) of these 114 patients had been seen by a medical social worker, of whom 16 were on MAF Plus funding. 14 of the remaining 59 patients were subsidised by MediFund, whereas the remainder were self-paying. 30 (26.3%) patients in total were on some form of subsidy, and 28 (24.6%) patients were on combination therapy. Of this group, nine were receiving MAF Plus subsidies.@*CONCLUSION@#Fewer than expected patients were found to be receiving drug subsidies for PAH. This was partly due to insufficient referrals and lack of requests for financial assistance. Patients on combination therapy had greater financial challenges. This study should spur us on to study funding gaps further and address them.

Obesity and Erectile Dysfunction: From Bench to Clinical Implication

Obesity is a major public health issue worldwide and is frequently associated with erectile dysfunction (ED). Both conditions may share an internal pathologic environment, also known as common soil. Their main pathophysiologic processes are oxidative stress, inflammation, and resultant insulin and leptin resistance. Moreover, the severity of ED is correlated with comorbid medical conditions, including obesity. Therefore, amelioration of these comorbidities may increase the efficacy of ED treatment with phosphodiesterase 5 inhibitors, the first-line medication for patients with ED. Although metformin was originally developed as an insulin sensitizer six decades ago, it has also been shown to improve leptin resistance. In addition, metformin has been reported to reduce oxidative stress, inflammatory response, and body weight, as well as improve ED, in animal and human studies. Moreover, administration of a combination of metformin and phosphodiesterase 5 inhibitors improves erectile function in patients with ED who have a poor response to sildenafil and are insulin resistant. Thus, concomitant treatment of metabolic derangements associated with obesity in patients with ED who are obese would improve the efficacy and reduce the refractory response to penile vasodilators. In this review, we discuss the connecting factors between obesity and ED and the possible combined treatment modalities.

No Causal Link between Phosphodiesterase Type 5 Inhibition and Melanoma

PURPOSE: To examine the association between phosphodiesterase type 5 (PDE5) inhibitor use and melanoma by 1) conducting a systematic review of observational studies; and 2) determining if low PDE5A gene expression in human melanoma correlated with decreased overall survival. MATERIALS AND METHODS: A systematic search of observational studies examining the association between PDE5 inhibitor use and melanoma was performed through ClinicalTrials.gov, the Cochrane Library, EMBASE, PubMed, and Web of Science databases, and seven eligible studies were identified. PDE5A gene expression was analyzed with RNA sequencing data from 471 human melanoma samples obtained from The Cancer Genome Atlas. RESULTS: Four studies reported a positive association between PDE5 inhibitor use and melanoma, and three studies found no correlation. RNA sequencing data analysis revealed that under-expression of the PDE5A gene did not impact clinical outcomes in melanoma. CONCLUSIONS: There is currently no evidence to suggest that PDE5 inhibition in patients causes increased risk for melanoma. The few observational studies that demonstrated a positive association between PDE5 inhibitor use and melanoma often failed to account for major confounders. Nonetheless, the substantial evidence implicating PDE5 inhibition in the cyclic guanosine monophosphate (cGMP)-mediated melanoma pathway warrants further investigation in the clinical setting.

Acute Hemodynamic Changes after Single Administration of Udenafil in Pulmonary Arterial Hypertension: a Phase IIa Study

BACKGROUND AND OBJECTIVES: Udenafil, a new phosphodiesterase-5 inhibitor (PDE5i), has been used to treat erectile dysfunction. Given the proven benefit of PDE5i in pulmonary arterial hypertension (PAH), we evaluated serial hemodynamic changes after single udenafil administration to determine the appropriate therapeutic dose. METHODS: Eighteen patients were randomly allocated into one of 3 groups: placebo, udenafil 50 mg (U50), and udenafil 100 mg (U100). Diagnosis for inclusion was idiopathic PAH or PAH associated with connective tissue disease. Patients with any contraindication to PDE5i, and/or PDE5i treatment in the past 1 month were excluded. Continuous hemodynamic monitoring was performed by placing a Swan-Ganz catheter. Information on cardiac index (CI), mean pulmonary arterial pressure (mPAP), mean systemic arterial pressure (mSAP), pulmonary arterial wedge pressure (PAWP), and pulmonary vascular resistance index (PVRI) was obtained for 4 hours after drug administration. RESULTS: The mPAP significantly decreased in both the U50 and U100 (−11 mmHg and −8 mmHg from baseline, respectively, p < 0.1). The mSAP also decreased in both U50 and U100; however, the decrease was greater in the U100 (Δ=−8.5 mmHg and Δ=−14.0 mmHg). CI increased in the U50, but decreased in the U100. Although PVRI decreased in both, statistical significance was only achieved in the U50 compared to placebo. PAWP was stable during monitoring. U50 had at least 4 hour-effect after administration. Only 2 patients with U100 experienced mild adverse events. CONCLUSIONS: This is the first demonstration of the acute hemodynamic changes induced by udenafil. U50 is considered an optimal dose for treating PAH with more than 4-hour treatment effect. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01553721.

A Case of Sexual Enhancer Induced Fixed Drug Eruption / 대한피부과학회지

Fixed drug eruption is a commonly reported mucocutaneous drug eruption. A 61-year-old male presented to our clinic with a complaint of an itchy round erythematous patch on the left hand dorsum with myalgia. On taking medical history, the patient correlated the episode with the intake of an oral sexual enhancer that he had obtained over the counter. We found the medicine contained tadalafil and sildenafil in combination with herbal ingredients. A short course of oral corticosteroid therapy resulted in the complete resolution of the lesion leaving residual hyperpigmentation of the skin involved. Various sexual enhancers with fancy names and attractive packaging are available without requiring a doctor's prescription. Most contain phosphodiesterase-5 inhibitors in various concentrations, often with herbal additions. These drugs are used erratically by the lay public, and often produce side effects. Herein, we report a case of fixed drug rash related to a sexual enhancer, which we believe to be the first report in Korea.

Safety and Effectiveness of Once-Daily Tadalafil (5 mg) Therapy in Korean Men with Benign Prostatic Hyperplasia/Lower Urinary Tract Symptoms in a Real-World Clinical Setting: Results from a Post-Marketing Surveillance Study

PURPOSE: The aim of this study was to investigate the safety and effectiveness of tadalafil 5 mg once daily (quaque die [everyday], QD) among Korean men with benign prostatic hyperplasia (BPH)/lower urinary tract symptoms (LUTS) in a real-world clinical setting. MATERIALS AND METHODS: This was a single-country, prospective, observational cohort study in which patients newly prescribed tadalafil 5 mg QD for the treatment of BPH/LUTS were followed-up for 12±2 or 24±2 weeks, or to the last treatment, during post-marketing surveillance. Safety was evaluated in terms of the frequency of treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs). Effectiveness was assessed by changes in the International Prostate Symptom Score (IPSS) from baseline to each endpoint. RESULTS: All patients receiving ≥1 dose of tadalafil 5 mg QD (N=637) were included in the safety population. Two percent of patients (n=13) experienced 15 TEAEs of mild (n=10; 66.7%) or moderate (n=5; 33.3%) severity. No severe TEAEs and no SAEs were reported. Effectiveness evaluations included all patients receiving tadalafil who had both baseline and endpoint observations (12-week, N=265; 24-week, N=44). Compared with baseline, the mean IPSS total score (±standard error) significantly improved by 4.7±0.3 and 6.4±0.7 points at the 12- and 24-week endpoints, respectively (p<0.0001), with significant improvements also observed on the storage, voiding, and quality of life subscores. In total, 69.1% of the patients had a clinically meaningful ≥3-point improvement in the IPSS total score. CONCLUSIONS: Tadalafil 5 mg QD was well tolerated and effective in Korean men with BPH/LUTS in a real-world clinical setting.

Recent progress in study onneuroprotection of phosphodiesterase 5 inhibitors / 中国药理学通报

In recent years,the role of phosphodiesterase 5(PDE5)has been highlighted in the development and progression of neurological disease.PDE5 inhibitors show significant effect of neruoprotection,which may be related with some effects such as resistance to stroke,anti-oxidation,inhibition of neuroinflammation and amelioration of cognitive deficits.Based on the domestic and overseas researches about PDE5,this review systematically summarized the neuroprotection of PDE5 and their related mechanisms.

Rapid determination of phosphodiesterase 5 inhibitors in invigorative health food by paper spray ionization mass spectrometry method / 中国食品卫生杂志

Objective A rapid method was constructed for detection of 3 kinds of phosphodiesterase 5 (PDE5) inhibitors (sidenafil,vardalafil,tadalafil) in invigorative health food by paper spray ionization mass spectrometry (PSI-MS method).Methods The characteristic ions of the PDE5 inhibitors could be used for preliminary identification and semiquantitative analysis with internal standard method using PSI-MS method.Results The 24 kinds of commercially available health-care products includes capsule,tablet,pill,powder,wine,syrup and liquid were tested.Results from PSI-MS were consistent with the HPLC-UV date.The calibration curves of PSI-MS has a good linearity in a given range.The linear coefficients of analytes were higher than 0.99.The LODs of 3 kinds of PDE5 inhibitors were lower than 1.0 mg/L.The RSDs of this method ranged from 20％ to 24％.Conclusion The PSI-MS method was rapid,accurate and targeted,which is compliant for quickly screening the PDE5 inhibitors in large complex matrix samples.

Penile Erection Induced by Scoparone from Artemisia capillaris through the Nitric Oxide-Cyclic Guanosine Monophosphate Signaling Pathway

PURPOSE: The objective of this study was to evaluate the relaxant effect of scoparone from Artemisia capillaris on rabbit penile corpus cavernosum smooth muscle (PCCSM) and to elucidate the mechanism of action of scoparone for the treatment of erectile dysfunction (ED). MATERIALS AND METHODS: PCCSM that had been precontracted with phenylephrine was treated with 3 Artemisia herbs (A. princeps, A. capillaris, and A. iwayomogi) and 3 fractions (n-hexane, ethyl acetate, and n-butanol) with different concentrations (0.1, 0.5, 1.0, and 2.0 mg/mL). Four components (esculetin, scopoletin, capillarisin, and scoparone) isolated from A. capillaris were also evaluated. The PCCSM was preincubated with Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME) and 1H-[1,2,4] oxadiazolo [4,3-a]quinoxalin-1-one (ODQ). Cyclic nucleotides in the perfusate were measured by a radioimmunoassay. The interactions of scoparone with udenafil and rolipram were also evaluated. RESULTS: A. capillaris extract relaxed PCCSM in a concentration-dependent manner. Scoparone had the highest relaxant effect on PCCSM among the 4 components (esculetin, scopoletin, capillarisin, and scoparone) isolated from the ethyl acetate fraction. The application of scoparone on PCCSM pretreated with L-NAME and ODQ led to significantly less relaxation. Scoparone also increased the cyclic guanosine monophosphate (cGMP) levels in the perfusate in a concentration-dependent manner. Furthermore, scoparone enhanced udenafil- and rolipram-induced relaxation of the PCCSM. CONCLUSIONS: Scoparone relaxed the PCCSM mainly by activating the nitric oxide-cGMP signaling pathway, and it may be a new promising treatment for ED patients who do not completely respond to udenafil.

A Randomized, Placebo-Controlled, Double-Blind, Multi-Center Therapeutic Confirmatory Study to Evaluate the Safety and Efficacy of Avanafil in Korean Patients with Erectile Dysfunction

A multi-center, randomized, double-blind, placebo-controlled study was conducted with 158 subjects who were randomized to placebo or avanafil 50, 100, and 200 mg on demand for 8 weeks to evaluate the safety, tolerability, and efficacy of avanafil in the treatment of erectile dysfunction (ED) in Korean men. The primary outcome was the erectile function (EF) domain score of the International Index of Erectile Function (IIEF) questionnaire. Secondary outcomes included changes in the scores of IIEF questions 3 and 4 (IIEF Q3, Q4) from baseline, changes in all domain scores in the IIEF from baseline, Sexual Encounter Profile questions 2–5 (SEP2–5), the Global Efficacy Assessment Question (GEAQ), and the number of subjects whose EF domain score at the 8th week visit was ≥ 26. After 8 weeks of treatment, the dose groups except avanafil 50 mg scored significantly higher on the IIEF-EF domain from baseline than the placebo group. The changes from baseline in the avanafil group in IIEF Q3 (all doses) and Q4 (200 mg alone) were higher than the placebo group. The differences between avanafil and placebo groups were significant in SEP2 (100 and 200 mg) and SEP3–5 (200 mg). The differences in the GEAQ “Yes” response were also significant in the avanafil 100 and 200 mg groups. Regarding the ratio of normal EF at the end of the study, avanafil 200 mg differed significantly from the placebo. Most treatment-associated adverse events were mild and resolved spontaneously. This is a clinical trial study and was registered at www.ClinicalTrials.gov (Identifier: NCT02477436).

Postprostatectomy Erectile Dysfunction: A Review

In the current era of the early diagnosis of prostate cancer (PCa) and the development of minimally invasive surgical techniques, erectile dysfunction (ED) represents an important issue, with up to 68% of patients who undergo radical prostatectomy (RP) complaining of postoperative erectile function (EF) impairment. In this context, it is crucial to comprehensively consider all factors possibly associated with the prevention of post-RP ED throughout the entire clinical management of PCa patients. A careful assessment of both oncological and functional baseline characteristics should be carried out for each patient preoperatively. Baseline EF, together with age and the overall burden of comorbidities, has been strongly associated with the chance of post-RP EF recovery. With this goal in mind, internationally validated psychometric instruments are preferable for ensuring proper baseline EF evaluations, and questionnaires should be administered at the proper time before surgery. Careful preoperative counselling is also required, both to respect the patient's wishes and to avoid false expectations regarding eventual recovery of baseline EF. The advent of robotic surgery has led to improvements in the knowledge of prostate surgical anatomy, as reflected by the formal redefinition of nerve-sparing techniques. Overall, comparative studies have shown significantly better EF outcomes for robotic RP than for open techniques, although data from prospective trials have not always been consistent. Preclinical data and several prospective randomized trials have demonstrated the value of treating patients with oral phosphodiesterase 5 inhibitors (PDE5is) after surgery, with the concomitant potential benefit of early re-oxygenation of the erectile tissue, which appears to be crucial for avoiding the eventual penile structural changes that are associated with postoperative neuropraxia and ultimately result in severe ED. For patients who do not properly respond to PDE5is, proper counselling regarding intracavernous treatment should be considered, along with the further possibility of surgical treatment for ED involving the implantation of a penile prosthesis.

Recreational Use of Phosphodiesterase 5 Inhibitors and Its Associated Factors among Undergraduate Male Students in an Ethiopian University: A Cross-Sectional Study

PURPOSE: To assess the prevalence of phosphodiesterase 5 (PDE5) inhibitor use and associated factors among University of Gondar undergraduate students. MATERIALS AND METHODS: An institution-based, cross-sectional study, using a survey questionnaire, was conducted from October to December 2015 to assess PDE5 inhibitor use and associated factors among male students at the University of Gondar. A Self-Esteem and Relationship questionnaire (14 items), an International Index of Erectile Function questionnaire (15 items) and a questionnaire on PDE5 inhibitor use (14 items) were included in the survey. RESULTS: Across all respondents (age, 21.9±1.88 years), more than half (55.7%, n=233) had heard about PDE5 inhibitors, but only 23 men (5.5%) reported trying a PDE5 inhibitor drug at least once. Older students were more likely to use PDE5 inhibitors compared to younger students (adjusted odds ratio [AOR], 1.40; 95% confidence interval [CI], 1.109~1.768). Those students who were smokers were 5.15 times more likely to use PDE5 inhibitors as compared to their non-smoking counterparts (AOR, 5.15; 95% CI, 2.096~12.687). In addition, multivariate logistic regression showed that being in a relationship, alcohol use, greater number of cigarettes smoked per day, and more sexual partners were significantly associated with PDE5 inhibitor use. CONCLUSIONS: The prevalence of PDE5 inhibitor use among undergraduate students was 5.5%. Cigarette smoking and other substance use, older age, and greater number of sexual partners were significantly associated factors for PDE5 inhibitor use. These findings suggest that restricting access to PDE5 inhibitor drugs is essential to curtailing misuse among university students.

Inhibidores de fosfodiesterasa-5 para el tratamiento de la hipertensión arterial pulmonar / Phosphodiesterase-5 inhibitors for the treatment of pulmonary arterial hypertension

En cardiología clínica y experimental, los inhibidores de fosfodiesterasa-5 (PDE-5) han atraído el interés científico en años recientes como herramienta terapéutica para el tratamiento de la HAP. Las fosfodiesterasas son una superfamilia de enzimas que inactivan el adenosín monofosfato cíclico y el guanosín monofosfato cíclico, los segundos mensajeros de la prostaciclina y del óxido nítrico. El razonamiento para utilizar los inhibidores de PDE-5 en HAP se basa en su relativa selectividad por la circulación pulmonar y en su capacidad para sobreexpresar la vía del óxido nítrico por inhibición de la hidrólisis del guanosín monofosfato cíclico e incrementar sus concentraciones, lo cual produce efectos vasodilatadores, antiproliferativos y proapoptóticos que pueden revertir el remodelado vascular pulmonar. Además, pueden aumentar el inotropismo ventricular derecho al incrementar el adenosín monofosfato cíclico mediado por la inhibición de la fosfodiesterasa tipo 3 sensible al guanosín monofosfato cíclico. El sildenafil, el tadalafil y el vardenafil son 3 inhibidores de PDE-5 actualmente en uso clínico que comparten similar mecanismo de acción aunque presentan algunas diferencias significativas en potencia, selectividad por la PDE-5 y propiedades farmacocinéticas. Para el tratamiento de la HAP en pacientes en clase funcional II y III (NYHA/WHO), el sildenafil fue aprobado por la Food and Drug Administration y la European Medicines Agency en 2005; y tadalafil por la Food and Drug Administration y la European Medicines Agency en 2009. En México, el sildenafil y el tadalafil recibieron la aprobación por parte de la Comisión Federal para la Protección contra Riesgos Sanitarios para la misma indicación en 2010 y 2011 respectivamente.

In experimental and clinical cardiology, phosphodiesterase type 5 (PDE-5) inhibitors have brought scientific interest as a therapeutic tool in pulmonary arterial hypertension (PAH) management in recent years. Phosphodiesterases are a superfamily of enzymes that inactivate cyclic adenosine monophosphate and cyclic guanosine monophosphate, the second messengers of prostacyclin and nitric oxide. The rationale for the use of PDE-5 inhibitors in PAH is based on their capacity to overexpresss the nitric oxide pathway pursued inhibition of cyclic guanosine monophosphate hydrolysis. By increasing cyclic guanosine monophosphate levels it promotes vasodilation, antiproliferative and pro-apoptotic effects that may reverse pulmonary vascular remodeling. There is also evidence that these drugs may directly enhance right ventricular contractility through an increase in cyclic adenosine monophosphate mediated by the inhibition of the cyclic guanosine monophosphate -sensitive PDE-3. Sildenafil, tadalafil and vardenafil are 3 specific PDE-5 inhibitors in current clinical use, which share similar mechanisms of action but present some significant differences regarding potency, selectivity for PDE-5 and pharmacokinetic properties. Sildenafil received approval in 2005 by the Food and Drug Administration and the European Medicines Agency and tadalafil in 2009 by the Food and Drug Administration and the European Medicines Agency for the treatment of PAH in patients classified as NYHA/WHO functional class II and III. In Mexico, sildenafil and tadalafil were approved by Comisión Federal de Protección contra Riesgos Sanitarios for this indication in 2010 and 2011, respectively.

Un nuevo enfoque terapéutico para la disfunción eréctil: las ondas de choque de baja intensidad / A new therapeutic approach for erectile dysfunction: Low intensity shockwaves / Um novo enfoque terapêutico para a disfunção eréctil: as ondas de choque de baixa intensidade

La disfunción eréctil es la incapacidad de lograr o mantener una erección del pene para la penetración vaginal y el desempeño sexual satisfactorio; se la considera el segundo problema más frecuente de disfunción sexual en hombres, después de la eyaculación precoz, con una prevalencia aproximada del 30%. La mayoría de los casos de disfunción eréctil tienen origen orgánico, principalmente por enfermedades vasculares, pero también está asociada a factores psicológicos, neurológicos u hormonales, o a alteraciones estructurales. La terapia farmacológica con inhibidores de la 5-fosfodiesterasa ha tenido eficacia clínica, pero hay pacientes que no responden a ella. Por tal razón se recurrió a las ondas de choque de baja intensidad que mejoran la vascularización y el flujo sanguíneo del pene con lo que se logran erecciones que permiten mejorar la calidad de la vida sexual. En esta revisión se incluyen diferentes estudios que demuestran la efectividad de este tratamiento.

Erectile dysfunction is the inability to achieve or sustain a penile erection for vaginal penetration and satisfactory sexual performance. It is the second most frequent problem of sexual dysfunction in men, after premature ejaculation, with an approximate prevalence rate of 30%. Most cases of erectile dysfunction have an organic origin, mostly vascular diseases, but it is also associated with psychological, neurological, and hormonal factors, or with structural alterations of the penis. Therapy with 5-phosphodiesterase inhibitors has been clinically effective, but some patients do not respond to it. Lowintensity shock waves may improve penile vascularity and blood flow, leading to better erections, and improvement of the quality of sexual performance. In this review several studies are included that show the effectiveness of this treatment for erectile dysfunction.

A disfunção eréctil é a incapacidade de conseguir ou manter uma ereção do pénis para a penetração vaginal e o desempenho sexual satisfatório; se a considera o segundo problema mais frequente de disfunção sexual em homens, depois da ejaculação precoce, com uma prevalência aproximada de 30%. A maioria dos casos de disfunção eréctil têm origem orgânica, principalmente por doenças vasculares, mas também está associada a fatores psicológicos, neurológicos ou hormonais, ou a alterações estruturais. A terapia farmacológica com inibidores da 5-fosfodiesterasa teve eficácia clínica, mas há pacientes que não respondem a ela. Por tal razão se recorreu às ondas de choque de baixa intensidade que melhoram a vascularização e o fluxo sanguíneo do pénis com o que se conseguem ereções que permitem melhorar a qualidade da vida sexual. Nesta revisão se incluem diferentes estudos que demonstram a efetividade deste tratamento.

Hepatotoxicity following separate administration of two phosphodiesterase-5 inhibitors (sildenafil & tadalafil) and opioid (tramadol); evaluation of possible reversal following their withdrawal.

The use of phosphodiesterase-5 inhibitors (PDE5i) and tramadol in the absence of erectile and ejaculatory dysfunctions in Nigeria has become a norm. In this study, we comparatively assess the effects of chronic use of these drugs on hepatotoxicity. Fifty male albino wistar rats weighing 180–200g were randomly assigned into 5 groups (n=10) as follows; control, sildenafil (1mg/100g b.w), tadalafil (1mg/100g b.w), tramadol (2mg/100g b.w) and sildenafil+tramadol treated group (1mg/100g and 2mg/100g b.w, respectively). Drugs were orally administered, once, every two days for 8weeks, at the end of which five animals were sacrificed per group (batch 1), while the remaining five animals per group were allowed for another 8weeks without drug administration (batch 2). Serum concentration of liver enzymes (AST, ALT and ALP) and bilirubin were assessed in both batches. Serum concentrations of AST, ALT, ALP, total bilirubin and unconjugated bilirubin were significantly (p<0.001) increased in all treated groups (batch 1), while conjugated bilirubin concentration was significantly (p<0.001) reduced in all treated groups, compared with control. Serum concentrations of AST and ALT were significantly reduced in sildenafil (p<0.01), tadalafil (p<0.05), tramadol (p<0.001) and sildenafil+tramadol (p<0.001) recovery groups, compared with their treated groups. Total and unconjugated bilirubin fractions were significantly (p<0.05 and p<0.01, respectively) reduced in tadalafil recovery group, compared with the treated group. Sildenafil+tramadol recovery group showed significantly (p<0.001) reduced total and unconjugated bilirubin concentrations, compared with the treated group. Chronic administration of PDE5i and tramadol reversibly altered liver functions.

Effects of PDE type 5 inhibitors on Left Ventricular Diastolic Dysfunction in Resistant Hypertension / Efeitos dos Inibidores da PDE do Tipo 5 sobre a Disfunção Diastólica Ventricular Esquerda na Hipertensão Arterial Resistente

Resistant hypertension (RHTN) is a multifactorial disease characterized by blood pressure (BP) levels above goal (140/90 mmHg) in spite of the concurrent use of three or more antihypertensive drugs of different classes. Moreover, it is well known that RHTN subjects have high prevalence of left ventricular diastolic dysfunction (LVDD), which leads to increased risk of heart failure progression. This review gathers data from studies evaluating the effects of phosphodiesterase-5 (PDE-5) inhibitors (administration of acute sildenafil and short-term tadalafil) on diastolic function, biochemical and hemodynamic parameters in patients with RHTN. Acute study with sildenafil treatment found that inhibition of PDE-5 improved hemodynamic parameters and diastolic relaxation. In addition, short-term study with the use of tadalafil demonstrated improvement of LVDD, cGMP and BNP-32 levels, regardless of BP reduction. No endothelial function changes were observed in the studies. The findings of acute and short-term studies revealed potential therapeutic effects of IPDE-5 drugs on LVDD in RHTN patients.

A Hipertensão arterial resistente (HAR) é uma doença multifatorial caracterizada por níveis pressóricos acima das metas (140/90 mmHg), a despeito de tratamento farmacológico otimizado de 3 ou mais fármacos anti-hipertensivos de diferentes classes. Pacientes diagnosticados como hipertensos resistentes apresentam alta prevalência de disfunção diastólica do ventrículo esquerdo (DDVE) que proporciona risco aumentado para insuficiência cardíaca. Esta revisão reúne dados de estudos prévios avaliando os efeitos dos inibidores de fosfodiesterase-5 (PDE-5) (administração aguda de sildenafil e de curto prazo de tadalafil) na função diastólica e nos parâmetros bioquímicos e hemodinâmicos em pacientes com HAR. O estudo agudo com sildenafil demonstrou que a inibição da PDE-5 melhorou os parâmetros hemodinâmicos e de relaxamento diastólico. Além disso, o estudo curto prazo com o uso de tadalafil revelou melhora da DDVE e dos níveis de GMPc e BNP-32, independente de redução de pressão arterial. A função endotelial não apresentou alteração com ambos os tratamentos. Os resultados dos estudos agudo e de curto prazo sugerem efeitos terapêuticos potenciais dos fármacos inibidores da PDE-5 na disfunção diastólica em pacientes com HAR.

Mirodenafil Prevents Bladder Dysfunction Induced by Chronic Bladder Ischemia in Rats / 대한배뇨장애요실금학회지

PURPOSE: To investigate the protective effect of mirodenafil on bladder function in a rat model of chronic bladder ischemia (CBI). METHODS: Twenty-four Sprague-Dawley rats were randomized to three groups: untreated, sham-operated rats (control group); untreated, CBI model rats (CBI group); and CBI rats treated daily with 4 mg/kg mirodenafil (CBI+mirodenafil group). The CBI and CBI+mirodenafil groups underwent endothelial injury to the iliac arteries and were fed a 2% cholesterol diet after injury. Four weeks after surgery, the CBI+mirodenafil group started daily treatment with mirodenafil for four weeks. Eight weeks after surgery, continuous in vivo cystometry and in vivo organ bath studies of detrusor muscle strips were performed. RESULTS: in vivo cystometry revealed that the rats in the CBI group had a significantly higher micturition frequency, lower bladder capacity, and lower compliance than the rats in the control and CBI+mirodenafil groups. The detrusor muscle strip study showed that the magnitude of the carbachol-induced contractile response was significantly lower in the CBI group compared to either the control or CBI+mirodenafil group. Addition of daily mirodenafil after induction of CBI decreased the contractile response, compared to untreated CBI rats. CBI induced submucosal fibrosis and degenerative changes in bladder walls, which was reversed by the addition of mirodenafil. CONCLUSIONS: Daily treatment with mirodenafil showed protective effects against bladder dysfunction resulting from CBI in rats.

The risk factors, diagnosis and treatment guideline of erectile dysfunction

Erectile dysfunction (ED) can negatively impact the quality of life among men, and increasingly affects all age strata. This has led to an explosion of health information on ED both for patients and doctors, which may cause potentially harmful effects when misused or abused. Therefore, the necessity of developing a standardized, appropriate guideline for the diagnosis and management of ED is increasing. In this review, the author describes risk factors, diagnosis and treatment guidelines for ED, which can be usefully applied in clinical practice.