Search Results (176)

Background: Phosphodiesterase type 5 inhibitors (PDE5i), particularly tadalafil and sildenafil, are the first-line therapies for erectile dysfunction (ED). After the patent expiration of branded tadalafil in 2017, generic formulations became available. Despite equivalent efficacy, skepticism persists regarding the effectiveness and safety of generics. The SHIFT study aimed to evaluate the non-inferiority of a generic tadalafil (Dalerpen) compared with branded and other generic tadalafil in terms of clinical efficacy and patient satisfaction. Methods: A prospective, multicenter study was conducted involving 247 patients treated with tadalafil (either 5 mg or 20 mg) for ED. Patients switched from branded or other generic tadalafil to Dalerpen. Baseline and follow-up assessments included the International Index of Erectile Function—Erectile Function Domain (IIEF-EF) (primary endpoint), Sexual Encounter Profile (SEP-2 and SEP-3), and International Prostatic Symptom Score (IPSS). A one-month follow-up was performed. Results: A total of 247 patients were included in the final analysis. After switching to Dalerpen, significant improvements were observed in both IIEF-EF (18.8 ± 5.6 vs. 16.7 ± 5.4, p < 0.001) and IPSS scores (10.4 ± 6.7 vs. 11.2 ± 6.3, p < 0.001), though the minimal clinically important difference (MCID) was not reached. SEP-3 scores also significantly increased (3 ± 1.2 vs. 2 ± 1.1, p < 0.001). Multivariate analysis identified baseline IIEF, IPSS scores, and post-treatment IPSS as predictors of IIEF-EF improvement (p < 0.001). Switching to Dalerpen was an independent predictor of both IIEF-EF and IPSS improvement. No new adverse events were reported. Conclusions: The SHIFT study demonstrates that Dalerpen is non-inferior to branded tadalafil in terms of clinical efficacy, offering a reliable and cost-effective therapeutic option. Educating patients on bioequivalence and addressing concerns regarding generic drugs are essential to facilitate therapeutic switches. Full article

The development of functional endothelial monolayers on synthetic vascular grafts remains challenging, particularly for small-diameter vessels (<6 mm) prone to thrombosis. Here, we present a pharmacological strategy combining 8-(4-chlorophenylthio) adenosine 3′,5′-cyclic monophosphate sodium salt (pCPT-cAMP, a tight junction promoter) with nitric oxide/cGMP pathway agonists 3-morpholinosydnonimine (SIN-1), captopril, and sildenafil) to enhance endothelialization. In human umbilical vein endothelial cells (HUVECs), this four-agent cocktail induced a flat, extended phenotype with a 3-fold increased cell area and 57.5% fewer cells required for surface coverage compared to controls. Immunofluorescence analysis revealed enhanced ZO-1 expression and continuous tight junction formation, while sustained nitric oxide (NO) production (3.9-fold increase) and restored prostacyclin (PGI₂) secretion demonstrated preserved endothelial functionality. Anticoagulation assays confirmed a significant reduction in thrombus formation (p < 0.01) via dual inhibition of platelet activation and thrombin binding. These findings establish a synergistic drug combination that promotes rapid endothelialization while maintaining antithrombogenic activity, offering a promising solution for small-diameter vascular grafts. Further studies should validate long-term stability and translational potential in preclinical models. Full article

Phosphodiesterase type 5 (PDE5) inhibitors, including sildenafil, tadalafil, and vardenafil, are primarily prescribed for erectile dysfunction and pulmonary hypertension. Emerging evidence suggests they may also modulate inflammatory pathways and improve vascular function, but their effects on inflammatory biomarkers in humans remain incompletely defined. A systematic review and meta-analysis were conducted to evaluate the impact of PDE5 inhibitors on inflammatory and endothelial markers in adult humans. Randomized controlled trials comparing PDE5 inhibition to placebo were identified through electronic database searches. Outcomes included pro-inflammatory markers (TNF-α, IL-6, IL-8, CRP, VCAM-1, ICAM-1, P-selectin) and anti-inflammatory or signalling markers (IL-10, NO, cGMP), assessed at short-term (≤1 week), intermediate-term (4–6 weeks), or long-term (≥12 weeks) follow-up. Risk of bias was assessed using the Cochrane RoB 2 tool. A total of 20 studies comprising 1549 participants were included. Meta-analyses showed no significant short-term effects of PDE5 inhibition on TNF-α, IL-6, or CRP. Long-term treatment was associated with reduced IL-6 (SMD = −0.64, p = 0.002) and P-selectin (SMD = −0.57, p = 0.02), and increased cGMP (SMD = 0.87, p = 0.0003). Effects on IL-10 and nitric oxide were inconsistent across studies. Most trials had low risk of bias. PDE5 inhibitors may exert anti-inflammatory effects in long-term use by reducing vascular inflammation and enhancing cGMP signalling. These findings support further investigation of PDE5 in chronic inflammatory conditions. Full article

Background: Coagulation disorders, including both bleeding and thrombotic complications, are common in patients undergoing hemodialysis (HD). Here, we aimed to characterize platelet function in patients undergoing hemodialysis three times per week, compared to healthy controls. Methods: Platelet function was assessed using the Multiplate analyzer (Roche), which is based on multiple electrode impedance aggregometry. Platelet aggregation was induced using adenosine diphosphate (ADP), and the area under the curve (AUC) served as the primary endpoint. In addition, platelet counts and C-reactive protein (CRP) levels were measured. To further evaluate nitric oxide (NO)-mediated inhibition of platelet aggregation, blood samples were incubated with the NO donor, sodium nitroprusside (SNP), and the phosphodiesterase 5A (PDE5A) inhibitor, sildenafil. Results: A total of 60 patients undergoing HD and 67 healthy controls were included in the analysis. Patients receiving HD treatment had significantly lower platelet counts compared to healthy controls (226.9 ± 53.47 vs. 246.7 ± 47.21 G/L, p = 0.029). Platelet aggregation was markedly reduced in patients undergoing HD compared to controls (462.0 ± 266.54 vs. 644.5 ± 254.44 AU × min, p < 0.001) with a significant correlation for platelet count (r = 0.42, p = 0.001) and systemic inflammation as indicated by CRP levels (r = 0.28, p = 0.035). Following SNP and sildenafil administration, inhibition of platelet aggregation remained more pronounced in patients undergoing HD. However, the change in platelet aggregation after SNP/sildenafil treatment did not differ significantly between the groups. Conclusions: Patients undergoing HD exhibit altered platelet function, indicated by reduced aggregation and platelet counts, as well as an association with systemic inflammation. Multiple electrode impedance aggregometry appears to be a feasible method for detecting platelet function alterations in patients receiving HD treatment. Responsiveness to NO donors was preserved in patients undergoing HD. Further studies are needed to identify the underlying mechanisms, particularly the role of NO signaling in platelet dysfunction in patients undergoing HD. Full article

Background/Objectives: Phosphodiesterase 5 (PDE5) inhibitors, sildenafil, vardenafil, and tadalafil, activate the cyclic guanosine monophosphate pathway resulting in vascular smooth muscle relaxation. They have been tested for a broad variety of conditions from cancer to Alzheimer’s disease with a positive impact. The known mechanism of action of these drugs could not explain such a plethora of effects. We studied the influence of PDE5 inhibitors on lipid bilayers as a possible application point of their action. Methods: To monitor the membrane changes induced by PDE5 inhibitors, the differential scanning microcalorimetry and the molecular dynamics simulation were used. Results: We found that sildenafil, vardenafil, and tadalafil change elastic properties of model membranes: PDE5 inhibitors disorder thin membranes and order thick membranes. Moreover, PDE inhibitors were able to induce lipid interdigitation. To address the biological aspect of the findings, we performed molecular dynamics on smooth muscle cell’s lipid raft treated with PDE5 inhibitors and revealed the increased density of the lipids. Furthermore, we showed that the lipid condensation in the PDE inhibitors presence increases nitric oxide permeability. Conclusions: The obtained results may be of biological relevance as lipid raft thickening might have an impact on membrane protein function. Moreover, improved nitric oxide flow through membrane may partially explain therapeutic action of these drugs. The presented results are useful for finding novel implications for PDE inhibitors. Full article

Background: This case report describes the surgical management of pulmonary artery banding (PAB) in a cat diagnosed with an incomplete atrioventricular canal (AVC) defect and a concurrent muscular septal defect. It highlights the use of PAB as a palliative treatment to manage this rare congenital heart condition in companion animals. Case Presentation: A 9-month-old European long-haired male cat presented with clinical signs of heart failure. Pharmacological treatment with sildenafil and furosemide failed to stabilize the patient’s condition. Echocardiographic assessment revealed an incomplete AVC type A and a muscular septal defect. Pulmonary artery banding was performed to reduce pulmonary blood flow and alleviate heart failure symptoms. Pre- and postoperative echocardiographic evaluations were conducted to monitor structural and functional changes in the heart. Post-surgical outcomes included a marked reduction in the size of the right atrium and ventricle and a stable pulmonary artery flow velocity of 3.8 m/s. The cat has remained in very good condition without the need for pharmacotherapy for 13 months post-surgery and is still alive at the time of reporting. Conclusions: PAB proved effective as a palliative intervention for managing an incomplete AVC in this feline patient. The successful outcome suggests that PAB may offer significant long-term benefits and improved survival in selected cases of incomplete AVCs in cats. Full article

Background and Objectives: The pulmonary artery pulsatility index (PAPi) is an emerging marker of right ventricular (RV) injury but has not been well investigated in acute pulmonary embolism (PE) or chronic thromboembolic pulmonary hypertension (CTEPH). We aimed to investigate its discriminatory capabilities and ability to detect therapeutic effects in acute PE and CTEPH. Materials and Methods: This was a secondary analysis of data from both experimental studies of autologous PE and human studies of acute PE and CTEPH. PAPi was calculated and compared in (1) PE versus sham and (2) before and after interventions aimed at reducing RV afterload in PE and CTEPH. The correlations between PAPi, cardiac output, and RV to pulmonary artery coupling were investigated. Results: PAPi did not differ between animals with acute PE versus sham, nor was it affected by clot burden (p = 0.673) or at a 30-day follow-up (p = 0.242). Pulmonary vasodilatation with oxygen was associated with a reduction in PAPi (4.9 [3.7–7.8] vs. 4.0 [3.2–5.6], p = 0.016), whereas positive inotropes increased PAPi in the experimental PE. In humans, PAPi did not change consistently with interventions. Balloon pulmonary angioplasty did not significantly increase PAPi (6.5 [4.3–10.7] vs. 9.8 [6.8–14.2], p = 0.1) in patients with CTEPH, and a non-significant reduction in PAPi (4.3 ± 1.6 vs. 3.3 ± 1.2, p = 0.074) was observed in patients with acute PE who received sildenafil. PAPi did not correlate well with cardiac output or measures of RV to pulmonary artery coupling in either species. Conclusions: PAPi did not detect acute, experimental PE or changes as a result of therapeutic interventions in patients with hemodynamically stable acute PE or CTEPH. However, it did change with pharmacological interventions in the experimental PE. Further research should establish its utility in detecting and monitoring RV injury in different clinical phenotypes of acute PE and CTEPH. Full article

Sildenafil is used to treat erectile dysfunction and pulmonary arterial hypertension but is often illicitly added to energy drinks and chocolates. This study introduces a lateral flow strip test using aptamers specific to sildenafil for detecting its illegal presence in food. The process involved using graphene oxide SELEX to identify high-affinity aptamers, which were then converted into molecular gate structures on mesoporous silica nanoparticles, creating a unique signaling system. This system was integrated into lateral flow chromatography strips and tested on buffers and chocolate samples containing sildenafil. The method simplifies the lateral flow assay (LFA) for small molecules and provides a tool for signal amplification. The detection limit for these strips was found to be 68.2 nM (31.8 µg/kg) in spiked food samples. Full article

Erectile dysfunction (ED) is a multifactorial social problem affecting men worldwide. While phosphodiesterase type 5 inhibitors (PDE5) like sildenafil are commonly used, they often present side effects, underscoring the need for alternative therapies. Therefore, this study investigated the potential of phytochemicals from Detarium senegalense in the management of ED. A library of phytochemicals from Detarium senegalense was generated, prepared, and interacted with six key enzymes implicated in ED, including PDE5, using the Schrödinger Maestro suite. The results identified catechin, epicatechin, and gallic acid as the leading compounds with significant binding affinities for the targeted enzymes. Catechin and epicatechin (−9.877 and −11.408 kcal/mol, respectively) exhibited comparable binding affinities to sildenafil (−11.926 kcal/mol) on PDE5. The MD simulation results also revealed superior stability and ability to maintain interaction with key amino acids at the active site of PDE5 over the entire simulation period for these compounds. These compounds also demonstrated favorable ADMET profiles over sildenafil, including high gastrointestinal absorption and no violation of Lipinski’s rule, indicating good bioavailability and drug likeness. These findings suggest that flavonoids from Detarium senegalense, especially catechin and epicatechin, have potential in the management of ED by interacting with multiple targets involved in its pathogenesis. Full article

The present study tested sildenafil citrate as an example of pharmacological repositioning against the opportunistic pathogen Pseudomonas aeruginosa, known for its potent biofilm formation. We evaluated its antimicrobial, synergistic, and antibiofilm effects using broth microdilution, checkerboard assays, and atomic force microscopy techniques. Sildenafil citrate showed antimicrobial activity, effectively inhibiting bacterial growth at minimum inhibitory concentrations ranging from 3.12 to 6.25 mg/mL and minimum bactericidal concentrations between 3.12 and 25 mg/mL. When combined with reference antimicrobial agents—cefepime, imipenem, cilastatin, and polymyxin—sildenafil citrate had a synergistic effect. It also effectively inhibited and eradicated biofilms, reducing total biomass by 87.1% for inhibition and 83.8% for eradication. Atomic force microscopy confirmed the efficacy of sildenafil citrate in destroying and inhibiting biofilms, decreasing the overall amplitude of the biofilm. Consequently, sildenafil citrate appears to be a promising candidate for combination with commercial antimicrobial drugs to prevent and treat P. aeruginosa infections. Full article

The therapeutic potential of combining 5-FU with repurposed drugs such as Sildenafil, Tezosentan, Levosimendan, and Resveratrol was investigated in lung cancer treatment using the A549 cell line. This study aimed to enhance 5-FU efficacy while mitigating side effects and overcoming drug resistance. The cytotoxic effects of 5-FU were assessed via MTT assay, with an IC₅₀ value of 5.03 µM for A549 cells. Subsequent experiments evaluated the impact of combining 5-FU with the aforementioned drugs on cell viability, clonogenic potential, and morphology. The results demonstrated that while Sildenafil and Tezosentan modestly improved 5-FU efficacy, Levosimendan reduced cell viability by 40% (p < 0.01) and Resveratrol by over 50% (p < 0.001), with clonogenicity reduced by up to 60% (p < 0.001). These findings suggest that combining 5-FU with Levosimendan or Resveratrol offers promising approaches for lung cancer therapy, potentially reducing the need for higher doses of 5-FU and minimizing associated toxicity. Future studies are warranted to elucidate the mechanisms underlying these interactions and assess their clinical relevance. Full article

Growing evidence suggests that neuroinflammation is not just a consequence of neurodegeneration in pathologies such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease or Amyotrophic lateral sclerosis, but it is rather a determinant factor, which plays a pivotal role in the onset and progression of these disorders. Neuroinflammation can affect cells and processes in the central nervous system (CNS) as well as immune cells, and might precede protein aggregation, which is a hallmark of the neurodegenerative process. Standard treatment methods are far from being able to counteract inflammation and delay neurodegeneration. Remarkably, phosphodiesterase 5 inhibitors (PDE5is), which represent potent vasoactive drugs used as a first-line treatment for erectile dysfunction (ED), display important anti-inflammatory effects through cyclic guanosine monophosphate (cGMP) level stabilization. Since PDE5 hydrolyzes cGMP, several studies positioned PDE5 as a therapeutic target, and more specifically, PDE5is as potential alternative strategies for the treatment of a variety of neurological disorders. Indeed, PDE5is can limit neuroinflammation and enhance synaptic plasticity, with beneficial effects on cognitive function and memory. The aim of this review is to provide an overview of some of the main processes underlying neuroinflammation and neurodegeneration which may be potential targets for PDE5is, focusing on sildenafil, the most extensively studied. Current strategies using PDEis for the treatment of neurodegenerative diseases will be summarized. Full article

Previous experimental findings have led to considerable interest in the beneficial effects on pulmonary hypertension (PH) produced by sildenafil and in the pleiotropic effects of rosuvastatin and their positive role in the process of pulmonary angiogenesis. However, magnesium sulfate, the most abundant intracellular cation, is essential in vascular endothelial functionality due to its anti-inflammatory and vasodilatory effects. Therefore, the present study aims to assess these treatment regimens and how they could potentially provide some additional benefits in PH therapy. Fourteen days after chronic-hypoxia PH was induced, rosuvastatin, sildenafil and magnesium sulfate were administered for an additional fourteen days to male Wistar rats. The Fulton Index, right ventricle (RV) anterior wall thickness, RV internal diameter and pulmonary arterial (PA) acceleration time/ejection time were evaluated, and another four biochemical parameters were calculated: brain natriuretic peptide, vascular endothelial growth factor, nitric oxide metabolites and endothelin 1. The present study demonstrates that sildenafil and rosuvastatin have modest effects in reducing RV hypertrophy and RV systolic pressure. The drug combination of sildenafil + rosuvastatin + magnesium sulfate recorded statistically very highly significant results on all parameters; through their positive synergistic effects on vascular endothelial function, oxidative stress and pathological RV remodeling, they attenuated PH in the chronic hypoxia pulmonary hypertension (CHPH) rat model. Full article

Cerebral ischemic stroke is a major cause of death worldwide due to brain cell death resulting from ischemia-reperfusion injury. However, effective treatment approaches for patients with ischemic stroke are still lacking in clinical practice. This study investigated the potential neuroprotective effects of sildenafil, a phosphodiesterase-5 inhibitor, in a gerbil model of global brain ischemia. We investigated the effects of sildenafil on the expression of glial fibrillary acidic protein and aquaporin-4, which are markers related to astrocyte activation and water homeostasis, respectively. Immunofluorescence analysis showed that the number of cells co-expressing these markers, which was elevated in the ischemia-induced group, was significantly reduced in the sildenafil-treated groups. This suggests that sildenafil may have a potential mitigating effect on astrocyte activation induced by ischemia. Additionally, we performed various behavioral tests, including the open-field test, novel object recognition, Barnes maze, Y-maze, and passive avoidance tests, to evaluate sildenafil’s effect on cognitive function impaired by ischemia. Overall, the results suggest that sildenafil may serve as a neuroprotective agent, potentially alleviating delayed neuronal cell death and improving cognitive function impaired by ischemia. Full article

The use of phosphodiesterase inhibitors in the treatment of Parkinson’s disease is currently widely discussed. The study aimed to investigate the impact of acute and chronic treatment with the phosphodiesterase 5 inhibitor, sildenafil, at low and moderate doses of 2 mg/kg and 6 mg/kg, and L-DOPA (12.5 mg/kg), alone or in combination, on asymmetric behavior and dopamine (DA) and serotonin metabolism in the striatum and substantia nigra of unilaterally 6-OHDA-lesioned rats. Acute administration of sildenafil at both tested doses jointly with L-DOPA significantly increased the number of contralateral rotations during a 2 h measurement compared to L-DOPA alone. The effect of a lower dose of sildenafil combined with L-DOPA was much greater in the second hour of measurement. However, the acute combined administration of a higher dose of sildenafil with L-DOPA resulted in an immediate and much stronger increase in the number of contralateral rotations compared to L-DOPA alone, already visible in the first hour of measurement. Interestingly, the chronic combined administration of 2 mg/kg of sildenafil and L-DOPA significantly reduced the number of contralateral rotations, especially during the first hour of measurement, compared to the long-term treatment with L-DOPA alone. Such an effect was not observed after the long-term combined treatment of a higher dose of sildenafil and L-DOPA compared to L-DOPA alone. The concentration of DA in the ipsilateral striatum and substantia nigra after the last combined chronic dose of sildenafil (2 or 6 mg/kg) and L-DOPA (12.5 mg/kg) was significantly higher than after L-DOPA alone. In spite of much stronger increases in the DA concentration in the ipsilateral striatum and substantia nigra, the number of contralateral rotations was reduced in the group of rats treated with the combination of 2 mg/kg sildenafil and L-DOPA compared to the group receiving L-DOPA alone. Moreover, the combined treatment with a low dose of sildenafil and L-DOPA had an opposite effect on DA catabolism, as assessed by DOPAC/DA and HVA/DA indexes, and these indexes were reduced in the ipsilateral striatum but increased in the contralateral striatum and substantia nigra compared to the treatment with L-DOPA alone. The results of the present study show that the addition of a low dose of a PDE5 inhibitor to the standard L-DOPA therapy differently modulates rotational behavior, the tissue DA concentration and its catabolism in the striatum and substantia nigra. Full article