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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]

Women with pulmonary arterial hypertension (PAH) exhibit better right ventricular (RV) function and survival than men; however, the underlying mechanisms are unknown. We hypothesized that 17[beta]-estradiol (E2), through estrogen receptor a (ER-[alpha]), attenuates PAH-induced RV failure (RVF) by upregulating the procontractile and prosurvival peptide apelin via a BMPR2-dependent mechanism. We found that ER-[alpha] and apelin expression were decreased in RV homogenates from patients with RVF and from rats with maladaptive (but not adaptive) RV remodeling. RV cardiomyocyte apelin abundance increased in vivo or in vitro after treatment with E2 or ER-[alpha] agonist. Studies employing ER-[alpha]-null or ER-[beta]-null mice, ER-[alpha] loss-of-function mutant rats, or siRNA demonstrated that ER-[alpha] is necessary for E2 to upregulate RV apelin. E2 and ER-[alpha] increased BMPR2 in pulmonary hypertension RVs and in isolated RV cardiomyocytes, associated with ER-[alpha] binding to the Bmpr2 promoter. BMPR2 is required for E2-mediated increases in apelin abundance, and both BMPR2 and apelin are necessary for E2 to exert RV-protective effects. E2 or ER-[alpha] agonist rescued monocrotaline pulmonary hypertension and restored RV apelin and BMPR2. We identified what we believe to be a novel cardioprotective E2/ER-[alpha]/BMPR2/apelin axis in the RV. Harnessing this axis may lead to novel RV-targeted therapies for PAH patients of either sex., Introduction Pulmonary arterial hypertension (PAH) is characterized by dysregulated vasoconstriction, muscularization of precapillary arteries, and formation of complex obstructive plexiform lesions in the pulmonary vasculature (1). This leads to increased [...]

Background and Aim: Portopulmonary hypertension (PoPH) is a complication associated with portal hypertension. Since the epidemiological study in Japan was limited, this study aimed to investigate the characteristics, treatment patterns, and prognosis of PoPH patients in real‐world data. Methods: The characteristics and treatment patterns of PoPH (n = 386) and portal hypertension without pulmonary arterial hypertension (portal hypertension w/o PAH) (n = 96 463) were analyzed based on the Medical Data Vision (MDV) dataset from April 2008 to September 2020. Survival‐time analyses of emergency hospitalization and mortality were also conducted between matched pair cohorts of PoPH (n = 210) and portal hypertension w/o PAH (n = 840). Results: Among 386 PoPH patients, the Child–Pugh classification of PoPH group comprised patients with Class A (59 [15.3%]), B (109 [28.2%]), and C (42 [10.9%]), and missing (176 [45.6%]). Regarding the feature of PoPH group, the proportion of primary biliary cholangitis (PBC) (13.7%) and splenomegaly (9.8%) was higher compared with portal hypertension w/o PAH group. The survival time of all‐cause hospitalization in PoPH group was shorter than portal hypertension w/o PAH group in matched pair cohort (P < 0.001 by log‐rank test). Of PoPH patients, the frequency of PAH‐specific medicine usage within 90 days was monotherapy of 79 patients (20.5%), combination therapy of 64 patients (16.6%), and PAH‐specific medicine usage of 243 patients (63.0%). Conclusion: This was the first study demonstrating that high proportion of PBC and splenomegaly and a greater risk of hospitalization were observed in PoPH patients based on the analysis using administrative claim database. [ABSTRACT FROM AUTHOR]

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]

Abstract Pulmonary arterial hypertension (PAH) encompasses a group of clinical entities characterized by sustained vasoconstriction and progressive vascular remodeling that act in concert to elevate pulmonary vascular resistance. The current treatments for PAH are mainly dedicated to target the process of vasoconstriction and do not offer a cure. There is now accumulating evidence that expansion of pulmonary artery cells due to increased proliferation and apoptotic evasion is a key pathological component of vascular remodeling that occurs in PAH. Thus, vascular lesions seen in advanced PAH patients present some cancer-like characteristics offering important avenues for exploration and expanding treatment options. In this review article, we will discuss recent advances into mechanisms underlying disease progression, with a focus on pulmonary artery smooth muscle cells. [ABSTRACT FROM AUTHOR]

The detailed molecular mechanisms of the pleiotropic effects of statins remain to be fully elucidated. Here, we hypothesized that cardioprotective effects of statins are mediated by small GTP-binding protein GDP dissociation stimulator (SmgGDS). SmgGDS(+/-) and wild-type (WT) mice were treated with continuous infusion of angiotensin II (Ang II) for 2 weeks with and without oral treatment with atorvastatin or pravastatin. At 2 weeks, the extents of Ang II-induced cardiac hypertrophy and fibrosis were comparable between the 2 genotypes. However, statins significantly attenuated cardiomyocyte hypertrophy and fibrosis in WT mice, but not in SmgGDS(+/-) mice. In SmgGDS(+/-) cardiac fibroblasts (CFs), Rac1 expression, extracellular signal-regulated kinases 1/2 activity, Rho-kinase activity, and inflammatory cytokines secretion in response to Ang II were significantly increased when compared with WT CFs. Atorvastatin significantly reduced Rac1 expression and oxidative stress in WT CFs, but not in SmgGDS(+/-) CFs. Furthermore, Bio-plex analysis revealed significant upregulations of inflammatory cytokines/chemokines and growth factors in SmgGDS(+/-) CFs when compared with WT CFs. Importantly, conditioned medium from SmgGDS(+/-) CFs increased B-type natriuretic peptide expression in rat cardiomyocytes to a greater extent than that from WT CFs. Furthermore, atorvastatin significantly increased SmgGDS secretion from mouse CFs. Finally, treatment with recombinant SmgGDS significantly reduced Rac1 expression in SmgGDS(+/-) CFs. These results indicate that both intracellular and extracellular SmgGDS play crucial roles in the inhibitory effects of statins on cardiac hypertrophy and fibrosis, partly through inhibition of Rac1, Rho kinase, and extracellular signal-regulated kinase 1/2 pathways, demonstrating the novel mechanism of the pleiotropic effects of statins. [ABSTRACT FROM AUTHOR]

Pulmonary arterial hypertension (PAH) is a progressive disorder characterized by a sustained elevation of pulmonary artery (PA) pressure, right ventricular failure, and premature death. Enhanced proliferation and resistance to apoptosis (as seen in cancer cells) of PA smooth muscle cells (PASMCs) is a major pathological hallmark contributing to pulmonary vascular remodeling in PAH, for which current therapies have only limited effects. Emerging evidence points toward a critical role for Enhancer of Zeste Homolog 2 (EZH2) in cancer cell proliferation and survival. However, its role in PAH remains largely unknown. The aim of this study was to determine whether EZH2 represents a new factor critically involved in the abnormal phenotype of PAH-PASMCs. We found that EZH2 is overexpressed in human lung tissues and isolated PASMCs from PAH patients compared to controls as well as in two animal models mimicking the disease. Through loss- and gain-of-function approaches, we showed that EZH2 promotes PAH-PASMC proliferation and survival. By combining quantitative transcriptomic and proteomic approaches in PAH-PASMCs subjected or not to EZH2 knockdown, we found that inhibition of EZH2 downregulates many factors involved in cell-cycle progression, including E2F targets, and contributes to maintain energy production. Notably, we found that EZH2 promotes expression of several nuclear-encoded components of the mitochondrial translation machinery and tricarboxylic acid cycle genes. Overall, this study provides evidence that, by overexpressing EZH2, PAH-PASMCs remove the physiological breaks that normally restrain their proliferation and susceptibility to apoptosis and suggests that EZH2 or downstream factors may serve as therapeutic targets to combat pulmonary vascular remodeling. [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]