scholarly journals Spontaneous Adult-Onset Pulmonary Arterial Hypertension Attributable to Increased Endothelial Oxidative Stress in a Murine Model of Hereditary Hemorrhagic Telangiectasia

2010 ◽  
Vol 30 (3) ◽  
pp. 509-517 ◽  
Author(s):  
Mourad Toporsian ◽  
Mirjana Jerkic ◽  
Yu-Qing Zhou ◽  
Mohammed G. Kabir ◽  
Lisa X. Yu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Murine Model ◽  
Hereditary Hemorrhagic Telangiectasia ◽  
Adult Onset ◽  
Pulmonary Arterial

Pulmonary arterial hypertension in families with hereditary hemorrhagic telangiectasia: a 13-year follow-up study

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
Y.-P Zhou ◽  
X Jiang ◽  
Y.-X Zhang ◽  
K Sun ◽  
T.-Y Lian ◽  
...  
Keyword(s):  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Hereditary Hemorrhagic Telangiectasia ◽  
Clinical Status ◽  
Development Program ◽  
Resistance Index ◽  
Walking Distance ◽  
Funding Source ◽  
Free Survival ◽  
Pulmonary Arterial

Abstract Background Pulmonary arterial hypertension (PAH) can occur in families with hereditary hemorrhagic telangiectasia (HHT), but it has not been well-characterized. Purpose This study sought to characterize the genetic defects, clinical and hemodynamic features, and outcomes of PAH patients in HHT families. Methods All HHT families with at least one case of PAH investigated in our center from January 2006 to December 2018 were enrolled in the study. We did whole-exome sequencing (WES) or whole-genome sequencing (WGS) to every proband and available family members. The clinical data, hemodynamic features and outcomes of PAH patients were reviewed. Results A total of 64 PAH patients in 57 families were enrolled. Only 7 (12.3%) families had more than one case of PAH. Activin-receptor-like kinase 1 (ALK-1) mutation and Endoglin (ENG) mutation were confirmed in 49 (86.0%) and 3 (5.3%) families and other 5 (8.8%) had no known mutation associated with HHT or PAH. The median age when PAH diagnosis was 22 [9–33] years and female was dominant (70.3%). Most patients (84.4%) had signs of HHT and anemia was recorded in 14 (21.9%) patients. Remarkably, these patients showed severely compromised hemodynamics with elevated mean pulmonary artery pressure (62 [51, 77] mm Hg) and pulmonary vascular resistance index (17.0 [11.2, 22.8] Wood units*m2). Also, impaired exercise capacity was recorded at diagnosis with decreased six-minute walking distance (410 [342–485] meters) and over half (54.7%) were in WHO functional class III or IV. The 1-, 3-, 5- and 10-year transplantation-free survival for the overall PAH patients was 95.0%, 75.9%, 67.1% and 36.4%, respectively. Anemia (HR: 4.24 [1.32–13.65], p=0.016) and CI <2.5 l/min/m2 (HR: 4.39 [1.20–16.09], p=0.026) were independent risk factors for mortality. Conclusions PAH in HHT families is a devastating condition characterized by a young age at PAH diagnosis, poor clinical status and outcomes mainly underlying ALK-1 mutation, which emphasizes the importance to pay attention to this group of patients. Transplantation-free survival Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): The Beijing Natural Science Foundation (7181009), the National Key Research and Development Program of China (2016YFC0901502)

scholarly journals Effects of ovariectomy on antioxidant defence systems in the right ventricle of female rats with pulmonary arterial hypertension induced by monocrotaline

2018 ◽  
Vol 96 (3) ◽  
pp. 295-303 ◽  
Author(s):  
Rafaela Siqueira ◽  
Rafael Colombo ◽  
Adriana Conzatti ◽  
Alexandre Luz de Castro ◽  
Cristina Campos Carraro ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Pulmonary Arterial Hypertension ◽  
Right Ventricle ◽  
Protein Expression ◽  
Arterial Hypertension ◽  
Female Rats ◽  
Antioxidant Defenses ◽  
Thioredoxin 1 ◽  
Pulmonary Arterial ◽  
The Right

The aim of this study was to evaluate the impact of ovariectomy on oxidative stress in the right ventricle (RV) of female rats with pulmonary arterial hypertension (PAH) induced by monocrotaline (MCT). Rats were divided into 4 groups (n = 6 per group): sham (S), sham + MCT (SM), ovariectomized (O), and ovariectomized + MCT (OM). MCT (60 mg·kg−1 i.p.) was injected 1 week after ovariectomy or sham surgery. Three weeks later, echocardiographic analysis and RV catheterisation were performed. RV morphometric, biochemical, and protein expression analysis through Western blotting were done. MCT promoted a slight increase in pulmonary artery pressure, without differences between the SM and OM groups, but did not induce RV hypertrophy. RV hydrogen peroxide increased in the MCT groups, but SOD, CAT, and GPx activities were also enhanced. Non-classical antioxidant defenses diminished in ovariectomized groups, probably due to a decrease in the nuclear factor Nrf2. Hemoxygenase-1 and thioredoxin-1 protein expression was increased in the OM group compared with SM, being accompanied by an elevation in the estrogen receptor β (ER-β). Hemoxygenase-1 and thioredoxin-1 may be involved in the modulation of oxidative stress in the OM group, and this could be responsible for attenuation of PAH and RV remodeling.

scholarly journals Hyperbaric oxygen effects on the alveoli-capillary unit in a murine model of pulmonary arterial hypertension

2020 ◽  
Author(s):  
Pedro J. Curi-Curi ◽  
Maria C. Castillo-Hernandez ◽  
Miguel Chavez-Martinez ◽  
Lilia Loredo-Mendoza ◽  
Eduardo Rios-Garcia ◽  
...  
Keyword(s):  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Hyperbaric Oxygen ◽  
Murine Model ◽  
Oxygen Effects ◽  
Pulmonary Arterial

Abstract 382: Cyclophilin A (CypA) is a Pathogenic Mediator of Pulmonary Arterial Hypertension

2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Chao Xue
Keyword(s):  
Oxidative Stress ◽  
Smooth Muscle ◽  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Specific Inhibitor ◽  
Cyclophilin A ◽  
Pulmonary Vasculature ◽  
Tunel Staining ◽  
Mesenchymal Transition ◽  
Pulmonary Arterial

Rationale: Pulmonary arterial hypertension (PAH) is a devastating disease in which oxidative stress has been proposed to mediate pathological changes to the pulmonary vasculature such as endothelial cell (EC) apoptosis, endothelial to mesenchymal transition (EndMT), vascular smooth muscle cell (VSMC) proliferation, and inflammation. Our previous study showed that cyclophilin A (CypA) was secreted from EC and VSMC in response to oxidative stress, and much of the secreted CypA was acetylated (AcK-CypA). Furthermore, CypA was increased in the plasma of patients with PAH. Objective: To evaluate the cell- s pecific role of CypA in PAH and compare the relative effects of AcK-CypA and CypA on EC apoptosis, development of an inflammatory EC phenotype and EndMT. Methods and Results: Transgenic overexpression of CypA in EC, but not SMC, caused a PAH phenotype including increased pulmonary artery pressure, α-smooth muscle actin expression in small arteries, and CD45 positive cells in the lungs. Mechanistic analysis using cultured mouse lung microvascular EC showed that CypA and AcK-CypA increased apoptosis measured by caspase 3 cleavage and TUNEL staining. MM284, a specific inhibitor of extracellular CypA, prevented EC apoptosis. In addition, CypA and AcK-CypA promoted an EC inflammatory phenotype assessed by increased VCAM1 and ICAM1 expression, phosphorylation of p65, and degradation of IkB. Furthermore, CypA and AcK-CypA promoted EndMT assayed by change in cell morphology, increased mesenchymal markers and EndMT related transcription factors. At all concentrations, AcK-CypA stimulated greater increases in apoptosis, inflammation and EndMT than CypA. Conclusions: EC-derived CypA (especially AcK-CypA) causes PAH by a presumptive mechanism involving increased EC apoptosis, inflammation and EndMT. Our results suggest that inhibiting extracellular secreted CypA is a novel therapeutic approach for PAH.

Abstract 263: Differential Effects of 17ß-Estradiol and 16a-Hydroxyestrone in Oxidative Stress and Proliferative Responses in Human Pulmonary Artery Smooth Muscle Cells - Implications in Pulmonary Arterial Hypertension

Hypertension ◽  
2013 ◽  
Vol 62 (suppl_1) ◽  
Author(s):  
Katie Y Hood ◽  
Augusto C Montezano ◽  
Margaret R MacLean ◽  
Rhian M Touyz
Keyword(s):  
Oxidative Stress ◽  
Pulmonary Arterial Hypertension ◽  
Cell Growth ◽  
Arterial Hypertension ◽  
Molecular Mechanisms ◽  
Antioxidant Systems ◽  
Ros Generation ◽  
Ros Production ◽  
Differential Effects ◽  
Pulmonary Arterial

Women develop pulmonary arterial hypertension (PAH) more frequently than men. This may relate, in part, to metabolism of 17β-estradiol (E2), leading to formation of the deleterious metabolite, 16α-hydroxyestrone (16α OHE1), which plays a role in the remodelling of pulmonary arteries. Molecular mechanisms whereby 16αOHE1 influences PASMC remodelling are unclear but ROS may be important, since oxidative stress has been implicated in the pathogenesis of PAH. We hypothesised that E2 and 16αOHE1 leads to Nox-induced ROS production, which promotes PASMC damage. Cultured PASMCs were stimulated with either E2 (1nM) or 16αOHE1 (1nM) in the presence/absence of EHT1864 (100μM, Rac1 inhibitor) or tempol (antioxidant; 10μM). ROS production was assessed by chemiluminescence (O2-) and Amplex Red (H2O2). Antioxidants (thioredoxin, peroxiredoxin 1 and NQ01), regulators of Nrf2 (BACH1, Nrf2) and, marker of cell growth (PCNA) were determined by immunoblotting. E2 increased O2- production at 4h (219 ± 30% vs vehicle; p<0.05), an effect blocked by EHT1864 and tempol. E2 also increased H2O2 generation (152 ± 4%; p<0.05). Thioredoxin, NQ01 and peroxiredoxin1 (71 ± 6%; 78 ± 9%; 69 ± 8%; p<0.05 respectively) levels were decreased by E2 as was PCNA expression (72 ± 2%; p<0.05). 16αOHE1 exhibited a rapid (5 min) and exaggerated increase in ROS production (355 ± 41%; p<0.05), blocked by tempol and EHT1864. This was associated with an increase in Nox4 expression (139 ± 11% vs vehicle, p<0.05). 16αOHE1 increased BACH1, (129 ± 3%; p<0.05), a competitor of Nrf2, which was decreased (92 ± 2%). In contrast, thioredoxin expression was increased by 16aOHE1 (154 ± 22%; p<0.05). PCNA (150 ± 5%) expression was also increased after exposure to 16αOHE1. In conclusion, E2 and 16αOHE1 have differential effects on redox processes associated with PASMC growth. Whereas E2 stimulates ROS production in a slow and sustained manner without effect on cell growth, 16αOHE1 upregulates Nox4 with associated rapid increase in ROS generation and downregulation of antioxidant systems, affecting proliferation. Our findings suggest that E2 -derived metabolites may promote a pro-proliferative PASMC phenotype through Nox4-derived ROS generation. These deleterious effects may impact on vascular remodeling in PAH.

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