Sildenafil for pulmonary hypertension in neonates: An updated systematic review and meta-analysis

Correlating Severity of Pulmonary Hypertension by Echocardiogram with Mortality in Premature Infants with Bronchopulmonary Dysplasia

OBJECTIVE

 Bronchopulmonary dysplasia (BPD) is the most common complication of preterm birth. Infants with BPD are at increased risk for pulmonary hypertension (PH). Cardiac catheterization is the gold standard for diagnosing PH, but cardiac catheterization is challenging to perform in small, sick, premature infants. The utility of echocardiography for diagnosing PH and predicting outcomes in extremely premature infants has not been clearly defined. Therefore, we sought to use predefined criteria to diagnose PH by echocardiogram and relate PH severity to mortality in extremely premature infants with BPD.

STUDY DESIGN

 Echocardiograms from 46 infants born ≤28 weeks' postmenstrual age with a diagnosis of BPD were assessed for PH by three pediatric cardiologists using predefined criteria, and survival times among categories of PH patients were compared. A total of 458 echocardiograms were reviewed, and 15 (33%) patients were found to have at least moderate PH. Patients with at least moderate PH had similar demographic characteristics to those with no/mild PH.

RESULTS

 Ninety percent of infants without moderate to severe PH survived to hospital discharge, compared with 67% of infants with at least moderate PH (p = 0.048). Patients with severe PH had decreased survival to hospital discharge (38%) compared with moderate (100%) and no/mild PH (90%) groups. Kaplan-Meier survival curves also differed among PH severity groups (Wilcoxon p < 0.001).

CONCLUSION

 Using predefined criteria for PH, premature infants with BPD can be stratified into PH severity categories. Patients diagnosed with severe PH by echocardiogram have significantly reduced survival.

KEY POINTS

· A composite score definition of PH by echocardiogram showed high inter- and intrarater reliability.. · Infants with severe PH by echocardiogram had decreased survival rates.. · Early diagnosis of PH by echocardiogram dictates treatment which may improve outcomes..

Neonatal persistent pulmonary hypertension related to a novel TBX4 mutation: case report and review of the literature

TBX4 gene, located on human chromosome 17q23.2, encodes for T-Box Transcription Factor 4, a transcription factor that belongs to the T-box gene family and it is involved in the regulation of some embryonic developmental processes, with a significant impact on respiratory and skeletal illnesses. Herein, we present the case of a female neonate with persistent pulmonary hypertension (PH) who underwent extracorporeal membrane oxygenation (ECMO) on the first day of life and then resulted to have a novel variant of the TBX4 gene identified by Next-Generation Sequencing. We review the available literature about the association between PH with neonatal onset or emerging during the first months of life and mutations of the TBX4 gene, and compare our case to previously reported cases. Of 24 cases described from 2010 to 2023 sixteen (66.7%) presented with PH soon after birth. Skeletal abnormalities have been described in 5 cases (20%). Eleven cases (46%) were due to de novo mutations. Three patients (12%) required ECMO. Identification of this variant in affected individuals has implications for perinatal and postnatal management and genetic counselling. We suggest including TBX4 in genetic studies of neonates with pulmonary hypertension, even in the absence of skeletal abnormalities.

Randomized Controlled Trials of Pulmonary Vasodilator Therapy Adjunctive to Inhaled Nitric Oxide for Persistent Pulmonary Hypertension of the Newborn: A Systematic Review

Inhaled nitric oxide (iNO) is a pulmonary vasodilator considered standard of care to treat persistent pulmonary hypertension of the newborn. However, not all infants respond to iNO. The authors performed a systematic review to examine methodology, outcomes, and challenges of randomized controlled trials testing pulmonary vasodilator medications adjunctive to iNO. The 5 trials identified showed heterogeneity in eligibility criteria and outcomes assessed. No trial achieved recruitment goals, limiting conclusions regarding efficacy, safety, and pharmacology. Trial design consensus and alternative methodologic strategies such as deferred consent, real-world controls, nonrandomized database assessments, and Bayesian statistical approaches are needed.

Comparison of treprostinil and oral sildenafil for the treatment of persistent pulmonary hypertension of the newborn: a retrospective cohort study

Background

This study aims to evaluate the effectiveness of treprostinil and oral sildenafil in managing persistent pulmonary hypertension of newborns (PPHN).

Methods

We conducted a retrospective cohort study of 42 neonates with PPHN treated with continuous intravenous treprostinil or oral sildenafil from January 2020 to October 2022 in China. Outcomes assessed included echocardiographic pulmonary artery systolic pressure (PASP), shunt direction, and arterial blood gas measures.

Results

Treprostinil lowered PASP and improved oxygenation significantly better than sildenafil on days 1, 2, and 3 of treatment (P < 0.05). Treprostinil also corrected shunt direction faster than sildenafil (P < 0.05). The duration of mechanical ventilation, length of NICU stay, and overall hospital stay did not significantly differ between the two groups (P > 0.05).

Conclusions

Treprostinil effectively lowers pulmonary artery pressure and improves oxygenation in neonates with PPHN, without being associated with severe complications. It may serve as a beneficial adjunct therapy for neonates with PPHN.

Electrospinning of pullulan-based orodispersible films containing sildenafil

Feasibility of electrospinning in the manufacturing of sildenafil-containing orodispersible films (ODFs) intended to enhance oxygenation and to reduce pulmonary arterial pressure in pediatric patients was evaluated. Given the targeted subjects, the simplest and safest formulation was chosen, using water as the only solvent and pullulan, a natural polymer, as the sole fiber-forming agent. A systematic characterization in terms of shear and extensional viscosity as well as surface tension of solutions containing different amounts of pullulan and sildenafil was carried out. Accordingly, electrospinning parameters enabling the continuous production, at the highest possible rate, of defect-free fibers with uniform diameter in the nanometer range were assessed. Morphology, microstructure, drug content and relevant solid state as well as ability of the resulting non-woven films to interact with aqueous fluids were evaluated. To better define the role of the fibrous nanostructure on the performance of ODFs, analogous films were produced by spin- and blade-coating and tested. Interestingly, the disintegration process of electrospun products turned out to be the fastest (i.e. occurring within few s) and compliant with Ph. Eur. and USP limits, making relevant ODFs particularly promising for increasing sildenafil bioavailability, thus lowering its dosages.

Comparison of the efficacy of inhaled versus infused milrinone in the management of persistent pulmonary hypertension of the newborn in resource-limited settings: A randomized clinical trial

BACKGROUND

The standard treatment for persistent pulmonary hypertension of the newborn (PPHN) is inhaled nitric oxide (iNO), which is not available in Iran. Consequently, other drugs, such as milrinone, are prescribed. So far, no study has investigated the effectiveness of inhaled milrinone in the management of PPHN. The present study aimed to improve the management of PPHN in the absence of iNO.

METHODS

In this randomized clinical trial, neonates with PPHN, admitted to the neonatal intensive care unit of Hazrat Ali-Asghar and Akbar-Abadi hospitals, were treated with intravenous dopamine infusion and randomly divided into two groups, receiving milrinone through inhalation or infusion rout. The neonates were evaluated by Doppler echocardiography, clinical examinations, and oxygen demand test. The neonates were also evaluated for the clinical symptoms and mortality in the follow-up.

RESULTS

A total of 31 infants, with a median age of 2 days (interquartile range = 4), were included in this study. There was a significant decrease in the peak systolic and mean pulmonary arterial pressure in both inhalation and infusion groups following milrinone administration, with no significant difference between the groups (p = 0.584 and p = 0.147, respectively). There was no significant difference between the two groups regarding the mean systolic blood pressure before and after treatment. Additionally, diastolic blood pressure was significantly lower in the infusion group after treatment (p = 0.020); however, the amount of reduction was not significantly different between the groups (p = 0.928). Overall, 83.9% of the participants achieved full recovery, 75% of whom were in the infusion group and 93.3% in the inhalation group (p = 0.186).

CONCLUSION

Milrinone inhalation can have similar effects to milrinone infusion as an adjunct treatment in the management of PPHN. Also, infusion and inhalation of milrinone showed similar safety.

Function of sildenafil on diseases other than urogenital system: An umbrella review

Background: To investigate the function of sildenafil on diseases other than urogenital system, an umbrella review was conducted. Methods: Meta-analysis and systematic reviews on this topic were comprehensively evaluated in this umbrella review. Quality of evidence was evaluated through AMSTAR and the Grading of Recommendations, Assessment, Development and Evaluation system to generate a reliable and valid conclusion. Results: 77 out of 1164 meta-analysis were enrolled. 33 significant outcomes and 41 non-significant outcomes were extracted from all eligible articles. We found sildenafil did significant help in reducing arterial systolic pressure, mean pulmonary arterial pressure, pulmonary arterial pressure, systolic pulmonary arterial pressure in patients with pulmonary and cardiovascular diseases. Besides, sildenafil also improved exercise capacity or performance in patients with pulmonary and cardiovascular diseases. Other than these patients, this drug contributed great help in pregnant women with fetal growth restriction and preeclampsia by increasing the weight of newborns and lowering uterine and umbilical pulsatility indices. Additionally, it was reported that utilization of sildenafil has brought increased risk of melanoma. Conclusion: We can conclude from our study that sildenafil played an important role in many fields, especially in vascular protection. This finding provides a strong evidence for further expansion of sildenafil utilization in other diseases.

Quantifying side effects and caregiver burdens of pediatric pulmonary hypertension therapies

BACKGROUND AND OBJECTIVES

Pulmonary hypertension (PH) is a rare, but serious disease among children. However, PH has been primarily evaluated among adults. Consequently, treatment therapies have not been fully evaluated among pediatric populations and are used in an 'off label' manner. The purpose of this study was to estimate the side effect profiles of the most commonly prescribed pediatric PH therapies and to understand the burdens placed upon families caring for children living with PH.

METHODS

Participants were recruited online through the "Families of children with pulmonary hypertension" Facebook group and asked to complete a survey about PH treatments.

RESULTS

A total of 139 parents of a child living with PH completed the survey. Almost all children used ≥ 1 medication to treat PH, with 52% using ≥ 3 medications. The highest average number of side effects was reported by users of Treprostinil, Selexipag and type-5 phosphodiesterase (PDE₅) inhibitors. The most common side effects were skin flushing, headache, nasal congestion, joint/muscle pain, and nausea. In terms of accessing care, 81% travel ≥ 20 miles and 68% travel for ≥ 60 min to receive care.

CONCLUSIONS

We found an array of treatment combinations employed to mitigate symptoms of PH in children, with a wide range of side effects. We also found a large, unseen economic, emotional, and time burden of caring for a child living with PH. Further research is warranted to understand the clinical implications of these side effects to move towards labeled usage of these therapies rather than post-hoc off-label usage.

Computational Drug Repurposing Approach to Identify Novel Inhibitors of ILK Protein for Treatment of Esophageal Squamous Cell Carcinoma

Purpose

Esophageal squamous cell cancer (ESCC) is a deadly malignant tumor characterized by an overall 5-year survival rate below 20%, with China accounting for approximately 50% of all cases worldwide. Our previous studies have demonstrated that high integrin-linked kinase (ILK) expression plays a key role in development and progression of ESCC both in vitro and in vivo. Here, we employed the drug repurposing approach to identify a novel FDA-approved anticancer inhibitor against ILK-induced tumorigenesis and progression.

Methods

We screened the ZINC15 database and predicted the molecular docking ability among FDA-approved and publicly available drugs to ILK and then performed computational docking and visual inspection analyses of the top 10 ranked drugs. Two computer-based virtual screened drugs were evaluated in vitro for their ability to directly bind purified ILK by surface plasmon resonance. Cytotoxicity of the two candidate drugs was validated in vitro using CCK-8 and LDH assays.

Results

We initially selected the top 10 compounds, based on their minimum binding energy to the ILK crystal, after molecular docking and subjected them to further screening. Taking the binding energy of -10 kcal/mol as the threshold, we selected two drugs, namely, nilotinib and teniposide, for the wet-lab experiment. Surface plasmon resonance (SPR) revealed that nilotinib and teniposide had equilibrium dissociation constant (KD) values of 6.410E - 6 and 1.793E - 6, respectively, which were lower than 2.643E - 6 observed in ILK-IN-3 used as the positive control. The IC50 values for nilotinib and teniposide in ESCC cell lines were 40 μM and 200-400 nM, respectively. Results of the CCK-8 assay demonstrated that both nilotinib and teniposide significantly inhibited proliferation of cells (P < 0.01). LDH results revealed that both drugs significantly suppressed the rate of cell death (P < 0.01).

Conclusion

The drug repositioning procedure can effectively identify new therapeutic tools for ESCC. Our findings suggest that nilotinib and teniposide are efficacious inhibitors of ILK and thus have potential to target ILK-mediated signaling pathways for management of ESCC.

Astragaloside IV ameliorates pulmonary vascular remodeling in hypoxia-induced pulmonary hypertension by restraining the T follicular helper cell response and expanding T follicular regulatory cell response

BACKGROUND

Pulmonary hypertension (PH) is a progressive disorder lacking a validated and effective therapy which characterized by elevated pulmonary arterial pressure, vascular remodeling and eventual death. FDA approved sildenafil is being used as a first-line drug for PH, however, neither survival rates nor quality of life have been improved because of side effects and patient noncompliance. Thus, the exploration of novel therapeutic drugs is urgently needed. Astragaloside IV (ASIV) exhibits a protective effect on HPH, but its mechanisms of action is unclear.

HYPOTHESIS

CD4+T cell subsets, Tfh and Tfr cells, may contribute to the development of chronic hypoxia-induced PH (HPH). We hypothesized that ASIV could effectively ameliorates pulmonary vascular remodeling of HPH by restraining the Tfh cell response and expanding Tfr cell response.

METHODS AND RESULTS

HPH mice model was established by exposure to chronic hypoxia for 21 days. Mice were randomly assigned to six groups: NaCl group, model group, SN group (100 mg/kg of sildenafil), low-dose group (20 mg/kg of ASIV), medium-dose group (40 mg/kg of ASIV) and high-dose group (80 mg/kg of ASIV). Primary culture and identification of distal pulmonary artery smooth muscle cells (PASMCs) in mice were established. Here, we demonstrated that ASIV treatment could significantly ameliorate the increase of mean PAP, RV/ (LV+S) ratio and PAMT in HPH mice. ASIV inhibited Tfh cell differentiation and IL-21 production, but promoted Tfr cell differentiation and TGF-β, IL-10 production. Chronic hypoxia promoted germinal center B cell responses, which inhibited by ASIV. ASIV regulated Tfh and Tfr cell differentiation by inhibiting the phosphorylation of mTOR signaling pathway, and the effect of ASIV-H was better than that observed in the SN group. ASIV inhibited the proliferation, migration and adhesion of PASMCs in vitro. Moreover, ASIV significantly downregulated the protein level of RhoA and upregulated the protein level of p27 in PASMCs under hypoxic condition.

CONCLUSION

Collectively, ASIV may regulate Tfh and Tfr cell responses to subsequently repress pulmonary vascular remodeling and hypoxic pulmonary hypertension.

The Role of Sildenafil in Treating Brain Injuries in Adults and Neonates

Sildenafil is a recognized treatment for patients suffering from erectile dysfunction and pulmonary hypertension. However, new evidence suggests that it may have a neuroprotective and a neurorestorative role in the central nervous system of both adults and neonates. Phosphodiesterase type 5-the target of sildenafil-is distributed in many cells throughout the body, including neurons and glial cells. This study is a comprehensive review of the demonstrated effects of sildenafil on the brain with respect to its function, extent of injury, neurons, neuroinflammation, myelination, and cerebral vessels.