scholarly journals Suppression of endothelial PGC-1α is associated with hypoxia-induced endothelial dysfunction and provides a new therapeutic target in pulmonary arterial hypertension

2016 ◽  
Vol 310 (11) ◽  
pp. L1233-L1242 ◽  
Author(s):  
Jia-Xin Ye ◽  
Shan-Shan Wang ◽  
Min Ge ◽  
Dong-Jin Wang
Keyword(s):  
Pulmonary Arterial Hypertension ◽  
Endothelial Dysfunction ◽  
Endothelial Function ◽  
Arterial Hypertension ◽  
Therapeutic Target ◽  
Negative Impact ◽  
Peroxisome Proliferator ◽  
Pulmonary Arterial

Endothelial dysfunction plays a principal role in the pathogenesis of pulmonary arterial hypertension (PAH), which is a fatal disease with limited effective clinical treatments. Mitochondrial dysregulation and oxidative stress are involved in endothelial dysfunction. Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) is a key regulator of cellular energy metabolism and a master regulator of mitochondrial biogenesis. However, the roles of PGC-1α in hypoxia-induced endothelial dysfunction are not completely understood. We hypothesized that hypoxia reduces PGC-1α expression and leads to endothelial dysfunction in hypoxia-induced PAH. We confirmed that hypoxia has a negative impact on endothelial PGC-1α in experimental PAH in vitro and in vivo. Hypoxia-induced PGC-1α inhibited the oxidative metabolism and mitochondrial function, whereas sustained PGC-1α decreased reactive oxygen species (ROS) formation, mitochondrial swelling, and NF-κB activation and increased ATP formation and endothelial nitric oxide synthase (eNOS) phosphorylation. Furthermore, hypoxia-induced changes in the mean pulmonary arterial pressure and right heart hypertrophy were nearly normal after intervention. These results suggest that PGC-1α is associated with endothelial function in hypoxia-induced PAH and that improved endothelial function is associated with improved cellular mitochondrial respiration, reduced inflammation and oxygen stress, and increased PGC-1α expression. Taken together, these findings indicate that PGC-1α may be a new therapeutic target in PAH.

Abstract 3570: A Critical and Novel Role of Nogo (Neurite Outgrowth Inhibitor) in Pulmonary Arterial Hypertension

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Gopinath Sutendra ◽  
Sebastien Bonnet ◽  
Paulette Wright ◽  
Peter Dromparis ◽  
Alois Haromy ◽  
...  
Keyword(s):  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Nuclear Translocation ◽  
Pulmonary Arteries ◽  
Over Expression ◽  
Nfat Activation ◽  
Pulmonary Arterial ◽  
Systemic Arteries

Nogo was first identified as an inhibitor of neuronal axonal regeneration. Recently, Nogo-B was implicated in the proliferative and anti-apoptotic remodeling in systemic arteries; reduced Nogo-B expression was seen in remodeled mouse femoral arteries following injury. Pulmonary arterial hypertension (PAH) is also characterized by proliferative/anti-apoptotic remodeling in pulmonary arteries (PA), sparing systemic vessels. PAH PA smooth muscle cells (PASMC) are characterized by mitochondrial hyperpolarization (increased ΔΨm), decreased production of reactive oxygen species (ROS) (suppressing mitochondria-dependent apoptosis), down-regulation of Kv1.5 and activation of the transcription factor NFAT (promoting contraction and proliferation). We found that in contrast to systemic vessels, Nogo-B expression is significantly increased in vivo and in vitro in PAs and PASMCs from patients (n=6) and mice (n=42) with PAH, compared to normals. We hypothesized that Nogo is involved in the pathogenesis of PAH . Nogo −/− mice (n=7) had a normal phenotype and, in contrast to Nogo +/+ , did not develop chronic hypoxia (CH)-induced PAH assessed invasively (catheterization, RV/LV+Septum) and non-invasively (pulmonary artery acceleration time and treadmill performance) (n=7, Table ). CH- Nogo +/+ PASMC had the expected increase in ΔΨm (measured by TMRM), decreased ROS (MitoSOX), increased [Ca ++ ] i (FLUO3), decreased Kv1.5 (immunohistochemistry) and NFAT activation (nuclear translocation). None of these changes occurred in CH- Nogo −/− PASMC while all were induced in normoxic Nogo +/+ PASMC by adenoviral over-expression of Nogo-B . Heterozygote CH- Nogo +/− (n=7) values were between Nogo −/− and Nogo +/+ suggesting a gene dose-dependent effect. Nogo is over-expressed in human and rodent PAH and induces critical features of the PAH phenotype. Nogo targeting might represent a novel and selective therapeutic strategy for PAH. Table

scholarly journals LncRNA-SMILR modulates RhoA/ROCK signaling by targeting miR-141 to regulate vascular remodeling in pulmonary arterial hypertension

2020 ◽  
Vol 319 (2) ◽  
pp. H377-H391 ◽  
Author(s):  
Si Lei ◽  
Fei Peng ◽  
Mei-Lei Li ◽  
Wen-Bing Duan ◽  
Cai-Qin Peng ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Long Noncoding Rna ◽  
Vascular Remodeling ◽  
Noncoding Rna ◽  
In Vivo Models ◽  
Pulmonary Arterial

Smooth muscle-enriched long noncoding RNA (SMILR), as a long noncoding RNA (lncRNA), was increased in pulmonary arterial hypertension (PAH) patients and in vitro and in vivo models. SMILR activated RhoA/ROCK signaling by targeting miR-141 to disinhibit its downstream target RhoA. SMILR knockdown or miR-141 overexpression inhibited hypoxia-induced cell proliferation and migration via repressing RhoA/ROCK signaling in pulmonary arterial smooth muscle cells (PASMCs), which was confirmed in vivo experiments that knockdown of SMILR inhibited vascular remodeling and alleviated PAH in rats. SMILR may be a promising and novel therapeutic target for the treatment and drug development of PAH.

scholarly journals Identification of Long Noncoding RNA H19 as a New Biomarker and Therapeutic Target in Right Ventricular Failure in Pulmonary Arterial Hypertension

Circulation ◽  
2020 ◽  
Vol 142 (15) ◽  
pp. 1464-1484 ◽  
Author(s):  
Junichi Omura ◽  
Karima Habbout ◽  
Tsukasa Shimauchi ◽  
Wen-Hui Wu ◽  
Sandra Breuils-Bonnet ◽  
...  
Keyword(s):  
Pulmonary Arterial Hypertension ◽  
Pulmonary Artery ◽  
Arterial Hypertension ◽  
Therapeutic Target ◽  
Noncoding Rna ◽  
Pulmonary Artery Banding ◽  
Pulmonary Arterial ◽  
Rv Function

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.

Peripheral Arterial Stiffness and Endothelial Dysfunction in Idiopathic and Scleroderma Associated Pulmonary Arterial Hypertension

2009 ◽  
Vol 36 (5) ◽  
pp. 970-975 ◽  
Author(s):  
NIR PELED ◽  
DAVID SHITRIT ◽  
BENJAMIN D. FOX ◽  
DEKEL SHLOMI ◽  
ANAT AMITAL ◽  
...  
Keyword(s):  
Pulmonary Arterial Hypertension ◽  
Endothelial Dysfunction ◽  
Arterial Stiffness ◽  
Endothelial Function ◽  
Arterial Hypertension ◽  
Systolic Pressure ◽  
Vascular Involvement ◽  
Pulmonary Pressure ◽  
Pulmonary Arterial ◽  
Peripheral Arterial

Objective.Pulmonary endothelial dysfunction and increased reflection of pulmonary pressure waves have been reported in pulmonary arterial hypertension (PAH). However, the systemic vascular involvement is not fully understood. Our study focused on the systemic arterial stiffness and endothelial involvement in idiopathic and scleroderma associated PAH.Methods.Peripheral arterial stiffness and endothelial function were evaluated in 38 patients with idiopathic (n = 28) and scleroderma associated (n = 10) PAH, and 21 control subjects (13 healthy; 8 with scleroderma and normal pulmonary pressure). All participants underwent clinical and cardiopulmonary evaluation. Arterial stiffness was measured through the fingertip tonometry derived augmentation index (AI), which is the boost increase in the late systolic pressure wave after the initial systolic shoulder. Endothelial function was measured by forearm blood flow dilatation response to brachial artery occlusion by a noninvasive plethysmograph (EndoPAT 2000), which is associated with nitric oxide-dependent vasodilatation and yields a peripheral arterial tone (PAT) ratio.Results.Mean systolic pulmonary pressure was 70.5 ± 21.6 mm Hg (idiopathic-PAH) and 69.3 ± 20 mm Hg (scleroderma-PAH). AI was higher in scleroderma patients (10.5% ± 19.6% in healthy controls, 9.0% ± 21.5% in idiopathic-PAH, 20.1% ± 19.1% in scleroderma-PAH, and 24.4% ± 18.9% in scleroderma-controls; nonsignificant). PAT ratio was significantly lower (p < 0.05) than control values in idiopathic-PAH and scleroderma-PAH (PAT ratio: control 2.20 ± 0.25; idiopathic 1.84 ± 0.51; scleroderma 1.66 ± 0.66). AI was not correlated to endothelial dysfunction. There were no differences between the 2 PAH patient groups in age, body mass index, New York Heart Association classification, or 6-min walk test.Conclusion.Our study shows a trend towards increased arterial stiffness in scleroderma (nonsignificant), and also peripheral endothelial dysfunction in idiopathic-PAH and in scleroderma-PAH. These findings suggest involvement of different vessels in scleroderma-PAH compared to idiopathic-PAH.

Suppression of endothelial CD39/ENTPD1 is associated with pulmonary vascular remodeling in pulmonary arterial hypertension

2015 ◽  
Vol 308 (10) ◽  
pp. L1046-L1057 ◽  
Author(s):  
Mikko H. Helenius ◽  
Sanna Vattulainen ◽  
Mark Orcholski ◽  
Joonas Aho ◽  
Anne Komulainen ◽  
...  
Keyword(s):  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Cell Activation ◽  
Purinergic Signaling ◽  
Vascular Dysfunction ◽  
Healthy Donors ◽  
Pulmonary Arterial ◽  
Novel Target

Endothelial cell (EC) dysfunction plays a role in the pathobiology of occlusive vasculopathy in pulmonary arterial hypertension (PAH). Purinergic signaling pathways, which consist of extracellular nucleotide and nucleoside-mediated cell signaling through specific receptors, are known to be important regulators of vascular tone and remodeling. Therefore, we hypothesized that abnormalities in the vascular purinergic microenvironment are associated with PAH. Enzymatic clearance is crucial to terminate unnecessary cell activation; one of the most abundantly expressed enzymes on the EC surface is E-NTPDase1/CD39, which hydrolyzes ATP and ADP to AMP. we used histological samples from patients and healthy donors, radioisotope-labeled substrates to measure ectoenzyme activity, and a variety of in vitro approaches to study the role of CD39 in PAH. Immunohistochemistry on human idiopathic PAH (IPAH) patients' lungs demonstrated that CD39 was significantly downregulated in the endothelium of diseased small arteries. Similarly, CD39 expression and activity were decreased in cultured pulmonary ECs from IPAH patients. Suppression of CD39 in vitro resulted in EC phenotypic switch that gave rise to apoptosis-resistant pulmonary arterial endothelial cells and promoted a microenvironment that induced vascular smooth muscle cell migration. we also identified that the ATP receptor P2Y11 is essential for ATP-mediated EC survival. Furthermore, we report that apelin, a known regulator of pulmonary vascular homeostasis, can potentiate the activity of CD39 both in vitro and in vivo. we conclude that sustained attenuation of CD39 activity through ATP accumulation is tightly linked to vascular dysfunction and remodeling in PAH and could represent a novel target for therapy.

scholarly journals Skeletal muscle mitochondrial oxidative phosphorylation function in idiopathic pulmonary arterial hypertension: in vivo and in vitro study

2018 ◽  
Vol 8 (2) ◽  
pp. 204589401876829 ◽  
Author(s):  
Sasiharan Sithamparanathan ◽  
Mariana C. Rocha ◽  
Jehill D. Parikh ◽  
Karolina A. Rygiel ◽  
Gavin Falkous ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Pulmonary Arterial Hypertension ◽  
Oxidative Phosphorylation ◽  
Arterial Hypertension ◽  
Idiopathic Pulmonary Arterial Hypertension ◽  
Mitochondrial Oxidative Phosphorylation ◽  
Pulmonary Vessels ◽  
Pulmonary Arterial

Mitochondrial dysfunction within the pulmonary vessels has been shown to contribute to the pathology of idiopathic pulmonary arterial hypertension (IPAH). We investigated the hypothesis of whether impaired exercise capacity observed in IPAH patients is in part due to primary mitochondrial oxidative phosphorylation (OXPHOS) dysfunction in skeletal muscle. This could lead to potentially new avenues of treatment beyond targeting the pulmonary vessels. Nine clinically stable participants with IPAH underwent cardiopulmonary exercise testing, in vivo and in vitro assessment of mitochondrial function by 31P-magnetic resonance spectroscopy (31P-MRS) and laboratory muscle biopsy analysis. 31P-MRS showed abnormal skeletal muscle bioenergetics with prolonged recovery times of phosphocreatine and abnormal muscle pH handling. Histochemistry and quadruple immunofluorescence performed on muscle biopsies showed normal function and subunit protein abundance of the complexes within the OXPHOS system. Our findings suggest that there is no primary mitochondrial OXPHOS dysfunction but raises the possibility of impaired oxygen delivery to the mitochondria affecting skeletal muscle bioenergetics during exercise.

Protective effects of isorhamnetin on pulmonary arterial hypertension: in vivo and in vitro studies

2020 ◽  
Vol 34 (10) ◽  
pp. 2730-2744
Author(s):  
Zhi Chang ◽  
Jia‐ling Wang ◽  
Zhi‐cheng Jing ◽  
Ping Ma ◽  
Qing‐bing Xu ◽  
...  
Keyword(s):  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
In Vitro Studies ◽  
Protective Effects ◽  
Pulmonary Arterial

Hyperproliferative apoptosis-resistant endothelial cells in idiopathic pulmonary arterial hypertension

2007 ◽  
Vol 293 (3) ◽  
pp. L548-L554 ◽  
Author(s):  
Fares A. Masri ◽  
Weiling Xu ◽  
Suzy A. A. Comhair ◽  
Kewal Asosingh ◽  
Michelle Koo ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Idiopathic Pulmonary Arterial Hypertension ◽  
Janus Kinase ◽  
Vascular Lesions ◽  
Nuclear Antigen ◽  
Pulmonary Arterial

Idiopathic pulmonary arterial hypertension (IPAH) is characterized by plexiform vascular lesions, which are hypothesized to arise from deregulated growth of pulmonary artery endothelial cells (PAEC). Here, functional and molecular differences among PAEC derived from IPAH and control human lungs were evaluated. Compared with control cells, IPAH PAEC had greater cell numbers in response to growth factors in culture due to increased proliferation as determined by bromodeoxyuridine incorporation and Ki67 nuclear antigen expression and decreased apoptosis as determined by caspase-3 activation and TdT-mediated dUTP nick end labeling assay. IPAH cells had greater migration than control cells but less organized tube formation in in vitro angiogenesis assay. Persistent activation of signal transducer and activator of transcription 3 (STAT3), a regulator of cell survival and angiogenesis, and increased expression of its downstream prosurvival target, Mcl-1, were identified in IPAH PAEC. A Janus kinase (JAK) selective inhibitor reduced STAT3 activation and blocked proliferation of IPAH cells. Phosphorylated STAT3 was detected in endothelial cells of IPAH lesions in vivo, suggesting that STAT3 activation plays a role in the proliferative pulmonary vascular lesions in IPAH lungs.

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