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Although pulmonary hypertension (PH) and Eisenmenger's syndrome (ES) are common complications in adult congenital heart disease (ACHD), the frequency of diagnostic tests and the incidence of PH/ES in patients with ACHD in Japanese clinical practice are unclear. Therefore, we sought to clarify the frequency of diagnostic tests and incidence of PH/ES in patients with ACHD using the Medical Data Vision (MDV) database, the largest anonymized database of diagnosis procedure combination hospitals in Japan. We conducted a retrospective cohort study using the MDV database (April 2008 to December 2021) of patients with ACHD (International Classificaiton of Diseases, 10th revision codes: Q203-204, Q210-213, Q250) aged ≥15 years. The frequency of laboratory/clinical tests and the incidence of PH/ES were calculated. Subgroup analyses were performed for the periods 2008–2015 and 2016–2021. Overall, 28219 ACHD patients were extracted from the MDV database (females 56.3%, males 43.7%; mean ± standard deviation age 44.7 ± 23.5 years). The mean ± standard deviation follow-up period was 2.5 ± 2.7 years. The frequencies of electrocardiography, ultrasonography, brain natriuretic peptide (BNP), N-terminal pro-BNP (NT-proBNP), right heart catheterization, and pulmonary function tests (DLCO) were 2149.8, 1054, 1233, 340, 40.0, and 6.0 per 1000 person-years, respectively. The incidence rate of PH/ES was 32.8 per 1000 person-years. The incidence rate of PH/ES increased from 24.6 to 46.7 per 1000 person-years from 2008–2015 to 2016–2021. We have clarified the frequency of diagnostic tests related to PH/ES and the incidence of PH/ES in patients with ACHD in clinical practice in Japan, including non-specialist institutions for PH. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Patient and Therapeutic Profiles of Pulmonary Hypertension in Chronic Lung Diseases in Japan: A Cohort Study Using a Claims Database." The original article contained a mistake in the alignment of the heading in Table 3. The corrected table is provided in the correction notice. The article discusses the CCI and NHYA classes of the PAH therapy group and the no treatment group in relation to COPD and ILD. The authors of the article are Kazuki Kitahara, Junichi Omura, Shingo Wada, and Seok-Won Kim. [Extracted from the article]

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease characterised by exuberant tissue remodelling and associated with high unmet medical needs. Outcomes are even worse when IPF results in secondary pulmonary hypertension (PH). Importantly, exaggerated resistance to cell death, excessive proliferation and enhanced synthetic capacity are key endophenotypes of both fibroblasts and pulmonary artery smooth muscle cells, suggesting shared molecular pathways. Under persistent injury, sustained activation of the DNA damage response (DDR) is integral to the preservation of cells survival and their capacity to proliferate. Checkpoint kinases 1 and 2 (CHK1/2) are key components of the DDR. The objective of this study was to assess the role of CHK1/2 in the development and progression of IPF and IPF+PH.Methods and Results: Increased expression of DNA damage markers and CHK1/2 were observed in lungs, remodelled pulmonary arteries and isolated fibroblasts from IPF patients and animal models. Blockade of CHK1/2 expression or activity-induced DNA damage overload and reverted the apoptosis-resistant and fibroproliferative phenotype of disease cells. Moreover, inhibition of CHK1/2 was sufficient to interfere with transforming growth factor beta 1-mediated fibroblast activation. Importantly, pharmacological inhibition of CHK1/2 using LY2606368 attenuated fibrosis and pulmonary vascular remodelling leading to improvement in respiratory mechanics and haemodynamic parameters in two animal models mimicking IPF and IPF+PH.Conclusion: This study identifies CHK1/2 as key regulators of lung fibrosis and provides a proof of principle for CHK1/2 inhibition as a potential novel therapeutic option for IPF and IPF+PH. [ABSTRACT FROM AUTHOR]

Background: Right ventricular (RV) function is the major determinant for both functional capacity and survival in patients with pulmonary arterial hypertension (PAH). Despite the recognized clinical importance of preserving RV function, the subcellular mechanisms that govern the transition from a compensated to a decompensated state remain poorly understood and as a consequence there are no clinically established treatments for RV failure and a paucity of clinically useful biomarkers. Accumulating evidence indicates that long noncoding RNAs are powerful regulators of cardiac development and disease. Nonetheless, their implication in adverse RV remodeling in PAH is unknown.Methods: Expression of the long noncoding RNA H19 was assessed by quantitative PCR in plasma and RV from patients categorized as control RV, compensated RV or decompensated RV based on clinical history and cardiac index. The impact of H19 suppression using GapmeR was explored in 2 rat models mimicking RV failure, namely the monocrotaline and pulmonary artery banding. Echocardiographic, hemodynamic, histological, and biochemical analyses were conducted. In vitro gain- and loss-of-function experiments were performed in rat cardiomyocytes.Results: We demonstrated that H19 is upregulated in decompensated RV from PAH patients and correlates with RV hypertrophy and fibrosis. Similar findings were observed in monocrotaline and pulmonary artery banding rats. We found that silencing H19 limits pathological RV hypertrophy, fibrosis and capillary rarefaction, thus preserving RV function in monocrotaline and pulmonary artery banding rats without affecting pulmonary vascular remodeling. This cardioprotective effect was accompanied by E2F transcription factor 1-mediated upregulation of enhancer of zeste homolog 2. In vitro, knockdown of H19 suppressed cardiomyocyte hypertrophy induced by phenylephrine, while its overexpression has the opposite effect. Finally, we demonstrated that circulating H19 levels in plasma discriminate PAH patients from controls, correlate with RV function and predict long-term survival in 2 independent idiopathic PAH cohorts. Moreover, H19 levels delineate subgroups of patients with differentiated prognosis when combined with the NT-proBNP (N-terminal pro-B-type natriuretic peptide) levels or the risk score proposed by both REVEAL (Registry to Evaluate Early and Long-Term PAH Disease Management) and the 2015 European Pulmonary Hypertension Guidelines.Conclusions: Our findings identify H19 as a new therapeutic target to impede the development of maladaptive RV remodeling and a promising biomarker of PAH severity and prognosis. [ABSTRACT FROM AUTHOR]

Pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) are fatal diseases; however, their pathogenesis still remains to be elucidated. We have recently screened novel pathogenic molecules and have performed drug discovery targeting those molecules. Pulmonary artery smooth muscle cells (PASMCs) in patients with PAH (PAH-PASMCs) have high proliferative properties like cancer cells, which leads to thickening and narrowing of distal pulmonary arteries. Thus, we conducted a comprehensive analysis of PAH-PASMCs and lung tissues to search for novel pathogenic proteins. We validated the pathogenic role of the selected proteins by using tissue-specific knockout mice. To confirm its clinical significance, we used patient-derived blood samples to evaluate the potential as a biomarker for diagnosis and prognosis. Finally, we conducted a high throughput screening and found inhibitors for the pathogenic proteins. [ABSTRACT FROM AUTHOR]

Background: Right ventricular failure (RVF) is the major prognostic factor for both morbidity and mortality in pulmonary hypertension. A better understanding of the molecular mechanisms accounting for the transition from a compensated (preserve cardiac output) RV hypertrophy (CRVH) to a decompensated (decrease cardiac output) DRVH in PAH patients is needed. Recent Omics analyses have demonstrated the deregulation of several long non-coding RNAs (LncRNAs) in heart failure, but their role in RVF remains unknown. The LncRNA H19 and its encoded miR-675 are regulated by the epigenetic repressor EZH2 and have been implicated in both hypertrophy and fibrosis processes, (2 features of RVF) but never been studied in RVF. We hypothesized that H19/miR-675 up-regulation is implicated in the development of DRVH and is driven by EZH2 repression. Methods and Results: By qRT-PCR we showed in human RV biopsies obtained from control donors (n=10), CRVH patients (n=7, Cardiac index > 2.2) and DRVH patients (n=12, PAH patients died from RVF), that H19 and miR-675 were specifically upregulated (p<0.001) in DRVH. Similar findings were found in the monocrotaline rat (n≈50 p<0.05). Interestingly H19/miR-675 up-regulation was RV specific as no change was seen in both LV and lung of DRVH patients and rats. In ≈70 patients, we showed that H19 plasma levels were up-regulated in PAH (p<0.001) and positively correlated with PAH severity (pulmonary vascular resistance, PA pressure, cardiac index and pro-BNP, p<0.05), this was also confirmed in rats. Mechanistically, we demonstrated that the up-regulation of H19/miR-675 is driven by the repression of EZH2 and that enhanced H19 expression is associated with reduced CamKII δ/GSK3/β-catenin signaling (p<0.05) which is implicated in hypertrophy & fibrosis. Therefore, as expected H19/miR-675 expression correlated positively with both RV fibrosis (p<0.01) and cardiomyocytes hypertrophy (p<0.05). Conclusions: We demonstrated for the first time that EZH2/H19/miR-675 axis is implicated in the transition from CRVH to DRVH in RVF by impacting both hypertrophy and fibrosis. Given its RV specificity, circulating H19 represents an attractive biomarker of RV function in PAH patients. The therapeutic value of H19 remains to be established. [ABSTRACT FROM AUTHOR]

Introduction: Pulmonary arterial hypertension (PAH) is characterized by enhanced proliferation and reduced apoptosis of pulmonary artery smooth muscle cells (PASMCs). Hypothesis: To discover a novel compound for PAH patients from the original 5,562 compounds of Tohoku University. Methods: We performed high-throughput screening using PASMCs from PAH patients (PAH-PASMCs). Next, we performed functional tests for emetine in vivo. Results: We found that emetine inhibits PAH-PASMC proliferation. Interestingly, emetine significantly reduced activities of HIF-1α and -2α in PAH-PASMCs (n=3 each, P <0.05). Consistently, emetine reduced secretion of inflammatory cytokines/chemokines and growth factors, and oxidative stress-augmenting proteins such as cyclophilin A and its receptor basigin in PAH-PASMCs (n=3 each, P <0.05). Moreover, emetine significantly suppressed Rho-kinase activity in PAH-PASMCs (n=3 each, P <0.05). Additionally, emetine increased apoptosis, detected by TUNEL assay and reduced the expression of the anti-apoptotic protein Bcl2 in PAH-PASMCs (n=3 each, P <0.05). Next, we performed functional tests for emetine in vivo. Six-week-old male SD rats were used for the two experimental PH models; monocrotaline-induced PH and Sugen/hypoxia-induced PH. In the prevention protocol, after subcutaneous injection of monocrotaline (60 mg/kg), the animals were assigned to the simultaneous oral administration with emetine (0.05 mg/kg/day) or vehicle for 3 weeks. Emetine significantly reduced right ventricular (RV) systolic pressure (57±3 vs. 77±4 mmHg), RV hypertrophy (0.40±0.02 vs. 0.50±0.02), and PA remodeling compared with controls (all P <0.01, n=10~15). In the treatment protocol, after establishment of PH with Sugen (20 mg/kg) and hypoxia (10% O2) for 3 weeks followed by normoxia for 6 weeks, the animals were assigned to the oral administration of emetine (0.05 mg/kg/day) or vehicle for additional 4 weeks. Emetine significantly reduced RV systolic pressure (93±5 vs. 59±5 mmHg), RV hypertrophy (0.52±0.04 vs. 0.35±0.02), and PA remodeling compared with controls (all P <0.01, n=10~12). Importantly, emetine significantly reduced TNF-α and MCP-1 in serum compared with vehicle controls, suggesting its potent anti-inflammatory effects in vivo. Finally, emetine significantly reduced protein levels of cyclophilin A, basigin, and Rho-kinase activities in both models in vivo. Conclusions: We identified emetine as a novel promising drug for the treatment of PAH. [ABSTRACT FROM AUTHOR]

Introduction: Pulmonary arterial hypertension (PAH) is a fatal disease characterized by enhanced proliferation of pulmonary artery smooth muscle cells (PASMCs). However, all the drugs in clinical use target pulmonary vascular dilatation, which may not be an effective target for patients with advanced PAH. Celastramycin is a benzoyl pyrrole-type compound originally found in a bacteria extract with anti-inflammatory effects. We aimed to discover a novel drug for PAH that inhibits PASMC proliferation. Methods and Results: We screened 5,562 compounds from original library using high-throughput screening (HTS) system. Among the compounds, we identified that celastramycin (CEL), a benzoyl pyrrole-type compound originally found in a bacteria extract, inhibited the proliferation of PASMCs from patients with PAH (PAH-PASMCs) in a dose-dependent manner with minimal effects on PASMCs from healthy donors (n=8 each, P <0.05). Moreover, cell toxicity assays showed that CEL inhibited cell proliferation without any cell death in PAH-PASMCs (n=8 each, P <0.05). Mechanistic analysis demonstrated that CEL significantly inhibited ERK and NF-κB signaling in PAH-PAMSCs compared with vehicle controls (both P <0.05, n=4 each). Moreover, CEL significantly reduced protein levels of bromodomain-containing protein 4 (BRD4), a member of the BET family with inflammatory property, compared with vehicle controls (both P <0.05, n=6 each). Consistently, CEL treatment reduced reactive oxygen species (ROS) production in PAH-PASMCs with increased protein levels of NF-E2-related factor 2, a master regulator of cellular response against oxidative stress (n=8 each, P <0.05). Furthermore, using a Seahorse apparatus, which provides information on mitochondrial function through real-time measurements of oxygen consumption rate (OCR) and extracellular acidification rate (ECAR), we found that CEL recovered mitochondrial function in PAH-PASMCs. Indeed, metabolome analysis showed that CEL increased metabolites in TCA cycle in PAH-PASMCs. Finally, CEL treatment significantly ameliorated hypoxia-induced pulmonary hypertension (PH) in mice, monocrotaline-induced PH in rats, and Sugen/hypoxia-induced PH in rats (all P <0.05), in which we found significantly reduced cytokines/chemokines and growth factors in lung homogenates (e.g. IL-2, IL-6, and M-CSF). Conclusions: CEL is a potential novel drug for the treatment of PAH with anti-proliferative, anti-oxidative, and anti-inflammatory effects. [ABSTRACT FROM AUTHOR]

Background: Pulmonary arterial hypertension (PAH) is a vascular remodeling disease characterized by persistent elevation of pulmonary vascular resistance, which results in a striking increase in right ventricular (RV) afterload and subsequent failure. Pulmonary artery (PA) smooth muscle cells (PASMCs) from PAH patients exhibit a cancer-like phenotype with increased glycolysis (Hexokinase 2 activity) and reduced glucose oxidation (inhibition of pyruvate dehydrogenase (PDH)) promoting cell proliferation and apoptosis-resistant contributing to obliteration of the PA lumen. Emerging evidence have demonstrated a critical role for the histone methyltransferase EZH2 in cancer cell survival and several EZH2 inhibitors are now clinically investigated. However, its role in PAH remains unknown. We hypothesized that EZH2 expression is upregulated in PAH-PASMCs leading to PA remodeling. Methods and Results: Using Western blot (WB), we showed that EZH2 is upregulated in lungs, distal PAs and isolated PASMCs from PAH patients (p<0.01, n=10) compared to controls. Consistently, increased EZH2 expression was found in distal PAs from animal models mimicking PAH (monocrotaline and Sugen/Hypoxia). Using proteomic LC-MSMS approach followed by Maxquant/Andromeda analysis in PASMCs isolated from 4 PAH patients, we identified 139 proteins differentially expressed (27 up-regulated ≥ 1.2 or and 112 down-regulated ≤ 0.84; p ≤ 0.05) following EZH2 knockdown. Results of KEGG pathway analysis revealed that the tricarboxylic acid (TCA) cycle, carbon metabolism and metabolic pathways were the top significant pathways (FDR p-value <10-4). This suggests that EZH2 is important for regulating bioenergetic metabolism in PAH-PASMCs. In agreement with this, pharmacological (GSK126 or EPZ-6438) or molecular (siEZH2) inhibition of EZH2 leads to reduced expression (WB) of Hexokinase 2, pPDH and PDH. This was associated with a significant reduction in PAH-PASMC proliferation (Ki67 labeling and EdU assay, p<0.001) and resistance to apoptosis (Annexin V assay p<0.001). Conclusion: We provide evidence that EZH2 is overexpressed in human PAH and implicated in the pro-proliferative and anti-apoptotic phenotype of PAH-PASMCs. [ABSTRACT FROM AUTHOR]