5-Aminosalicylic Acid Attenuates Monocrotaline-Induced Pulmonary Arterial Hypertension in Rats by Increasing the Expression of Nur77.

The aim of this study is to investigate the effect of 5-aminosalicylic acid (5-ASA) on monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH) in rats and its molecular mechanism. Sixty male Sprague-Dawley rats (250-300 g) were evenly randomized into six groups: control group; PAH group induced by MCT intraperitoneal injection (50 mg/kg) on day 1; and four PAH groups treated for 30 days from day 2 with 5-ASA at 50 (5-ASA-50 group), 100 (5-ASA-100 group), 150 (5-ASA-150 group), and 200 mg/kg/day (5-ASA-200 group), respectively. Body mass, weight increment, survival rates, pulmonary artery pressure (PAP), right ventricular hypertrophy index (RVHI), and the signal pathway regulated by 5-ASA were assessed. (1) Compared with the control group, the PAH group had lower body mass and weight increment, and relative to the latter, 5-ASA-treated groups had larger body mass and weight increment except for groups 5-ASA-150 and 5-ASA-200 and greater overall survival rates; (2) SPAP, DPAP, MPAP, and RVHI in 5-ASA-treated groups, except for MPAP and RVHI in 5-ASA-200 group, were lower than those in the PAH group; (3) compared with the PAH group, Nur77 expression in the pulmonary arteries of 5-ASA-treated groups was increased; and (4) expression of inflammatory mediators (NF-κB p65) was lower, while that of IκBα was higher in the pulmonary arteries of 5-ASA-treated groups and control group than that in the PAH group (all P < 0.05). 5-ASA attenuates PAH in MCT-injected rats, reducing pulmonary arterial pressures and right ventricular hypertrophy and improving survival rates, via the Nur77-NF-κB/IκBα pathway involved in modulating the pulmonary vascular remodeling.

The Application of Intravascular Ultrasound to Evaluate Pulmonary Vascular Properties and Mortality in Patients with Pulmonary Arterial Hypertension.

BACKGROUND: The aim of this study was to explore the application of intravascular ultrasound (IVUS) to evaluate pulmonary vascular properties and mortality in patients with pulmonary arterial hypertension (PAH). METHODS: Patients (n = 51) with systolic pulmonary artery pressures ≥ 40 mm Hg on echocardiography were prospectively enrolled. All patients underwent right-heart catheterization and IVUS and were divided into three groups: PAH associated with connective tissue diseases (group 1, n = 25), PAH due to other causes (group 2, n = 15), and patients with connective tissue diseases without pulmonary hypertension (group 3, n = 11). PAH groups (groups 1 and 2) were divided into distal (n = 22) and proximal (n = 18) remodeling subtypes on the basis of IVUS results. All patients were followed (19 ± 10 months) to compare the differences among clinical variables, pulmonary vascular properties, and survival rates. RESULTS: A total of 408 segments of pulmonary arteries were studied. The PAH groups demonstrated a greater mean wall thickness than group 3 (P < .01 for all). Pulmonary vascular mechanical properties, including compliance, distensibility, elastic modulus, and stiffness index ß, were found to be worse in the PAH groups than in group 3 (P < .01 for all), but they tended to be better in group 1 than in group 2. An inverse exponential association was found between pulmonary vascular mechanical properties and hemodynamics, with R(2) values ranging from 0.54 to 0.78 (P < .001). In the PAH groups, the mortality in group 1 was similar to that in group 2 (12% vs 13%, P > .05), while the distal remodeling subtype had higher mortality than the proximal remodeling subtype (23% vs 0%, P < .05). CONCLUSIONS: IVUS is useful in PAH assessment by evaluating pulmonary vascular properties and predicting mortality. The classification of the proximal and distal remodeling type of PAH may be proposed to predict mortality and evaluate the prognosis of patients with PAH in clinical practice.

Two-dimensional echocardiography in the assessment of long-term prognosis in patients with pulmonary arterial hypertension.

OBJECTIVE: To investigate the relationship between cardiac diastolic dysfunction and outcomes in patients with pulmonary arterial hypertension (PAH) and to clarify the potential effect of two-dimensional echocardiography (2D-echo) on prognostic value in patients with PAH. METHODS: Patients diagnosed with PAH (as WSPH (World Symposia on Pulmonary Hypertension) classification I) confirmed by right heart catheterization (RHC), received targeted monotherapy or combination therapy. 2D-echo parameters, World Health Organization (WHO) functional classification and 6-minute walking distance (6MWD) were recorded. The clinical prognosis of patients was assessed by the correlation between echo parameters and clinical 6MWD using receiver operating characteristic (ROC) curve analysis. RESULTS: Fifty-eight patients were included. Left and right ventricular diastolic dysfunction (LVDD and RVDD) scores measured by 2D-echo had good correlation with 6MWD at baseline (rLVDD  = -0.699; rRVDD  = -0.818, both P < 0.001) and at last follow-up (rLVDD  = -0.701; rRVDD  = -0.666, both P<0.001). Furthermore, bi-ventricular (LVDD + RVDD) scores measured by 2D-echo had a better correlation with 6MWD at baseline and last follow-up (r =  0.831; r = -0.771, both P < 0.001). ROC curve analysis showed that the area under curves (AUCs) for LVDD score, RVDD score and (LVDD + RVDD) scores were 0.823 (P < 0.0001), 0.737 (P = 0.0002), and 0.825 (P < 0.0001), respectively. Compared with ROC analysis of other single parameters, cardiac diastolic function score was more accurate in predicting survival in patients with PAH. CONCLUSION: LVDD score, RVDD score and (LVDD + RVDD) scores yielded a comprehensive quantitative assessment of LV and RV diastolic function that correlated moderately with clinical functional parameters and might be useful in the assessment of PAH.