Hyperproliferative apoptosis-resistant endothelial cells in idiopathic pulmonary arterial hypertension

Masri, Fares A.; Xu, Weiling; Comhair, Suzy; Asosingh, Kewal; Koo, Michelle; Vasanji, Amit; Drazba, Judith A.; Anand‐Apte, Bela; Erzurum, Serpil C.

doi:10.1152/ajplung.00428.2006

Cited by 326 publications

(345 citation statements)

References 38 publications

Supporting

Mentioning

316

Contrasting

Unclassified

Order By: Relevance

“…Moreover, Park and colleagues (33) reported the hyperactivation of PY-STAT3 in lungs of cav-1 Ϫ/Ϫ mice, which spontaneously developed PAH. Additionally, the increase in PY-STAT3 levels has now been confirmed in pulmonary arterial lesions of idiopathic PAH in humans (23), and a similar increase in STAT3 was also reported in lungs of mice with hypoxiainduced PAH (53). Thus the mechanisms of IL-6/STAT3 signal transduction from the plasma membrane to the cell interior in pulmonary arterial endothelial and vascular smooth muscle cells are of relevance to the pathobiology of PAH.…”

supporting

confidence: 59%

Cytoplasmic provenance of STAT3 and PY-STAT3 in the endolysosomal compartments in pulmonary arterial endothelial and smooth muscle cells: implications in pulmonary arterial hypertension

Mukhopadhyay

Shah

et al. 2008

American Journal of Physiology-Lung Cellular and Molecular Phys

View full text Add to dashboard Cite

PB. Cytoplasmic provenance of STAT3 and PY-STAT3 in the endolysosomal compartments in pulmonary arterial endothelial and smooth muscle cells: implications in pulmonary arterial hypertension. Am J Physiol Lung Cell Mol Physiol 294: L449-L468, 2008. First published December 14, 2007 doi:10.1152/ajplung.00377.2007.-Lung vascular lesions in pulmonary arterial hypertension (PAH) are characterized by enlarged, vacuolated ("megalocytotic") pulmonary arterial endothelial (PAEC) and smooth muscle cells (PASMC). We have recently proposed that dysfunction of vesicle tethers, soluble N-ethylmaleimide-sensitive factor attachment proteins (SNAPs), and SNAP receptors (SNAREs), leading to disruptions of intracellular trafficking in the Golgi to plasma membrane (centrifugal) and the plasma membrane to cell interior (centripetal) directions is a key causal mechanism in this disease. In PAH, there was a reciprocal relationship between loss of caveolin-1 (cav-1) in PAECs and increased expression of "activated" tyrosine-phosphorylated STAT3 (PY-STAT3) associated with a block in centrifugal trafficking to/through the Golgi organelle. In the present study, we investigated 1) whether centripetal trafficking of STAT3 and PY-STAT3 in PAECs and PASMCs was membrane-associated, and 2) whether this might be affected in PAH. Immunofluorescence and live cell imaging studies showed that, in both PAEC and PASMC, STAT3 was associated with cytoplasmic vesicles partially colocalizing with markers of the endolysosomal compartments (clathrin, EEA1, Rab5, Rab11, and LAMP1). Overexpression of cav-1 increased the targeting of STAT3 to lysosomes and inhibited STAT3 transcriptional activity. Exposure of PAECs to monocrotaline (MCT) pyrrole, which causes PAH in the rat, led to a loss of caveolar STAT3 with increased sequestration of STAT3 and PY-STAT3 in endosomes. In vivo, marked cytoplasmic sequestration of activated PY-STAT3 was a common feature in PAEC in the rat/MCT model and in cells in the proliferative arterial and plexiform lesions in PAH in humans. These data highlight the epigenetic regulation of centripetal cytokine and growth-factor signaling pathways and its modulation in PAH.caveolin-1; signaling endosome; monocrotaline PULMONARY ARTERIAL HYPERTENSION (PAH) is characterized by the reduction of the lumen of medium-sized pulmonary arteries by proliferating, enlarged, vacuolated, and apoptosis-resistant ("megalocytotic") pulmonary arterial endothelial (PAEC) and smooth muscle (PASMC) cells (42,43). We (24, 26 -28, 41-43, 47) recently proposed that dysfunction of vesicle tethers, soluble N-ethylmaleimide-sensitive factor attachment proteins (SNAPs), and SNAP receptors (SNAREs), leading to disruptions of intracellular trafficking from the Golgi to plasma membrane (centrifugal) and the plasma membrane to cell interior (centripetal) directions might represent a key subcellular mechanism leading to the changes observed in endothelial and vascular smooth muscle cells in PAH. We (24, 26 -28, 41-43, 47) have previously provided evidence for disrupt...

show abstract

supporting

confidence: 59%

Cytoplasmic provenance of STAT3 and PY-STAT3 in the endolysosomal compartments in pulmonary arterial endothelial and smooth muscle cells: implications in pulmonary arterial hypertension

Mukhopadhyay

Shah

et al. 2008

American Journal of Physiology-Lung Cellular and Molecular Phys

View full text Add to dashboard Cite

show abstract

“…STAT3 activation [tyrosine phosphorylated (PY)-STAT3] is emerging as an important factor in vascular diseases including PH. Activation of PY-STAT3 has been reported in a number of experimental models such as the MCT-(78), hypoxia-[reviewed in Mathew (81)], and myocardial infarction-induced PH (59), and also in ECs obtained from patients with idiopathic PAH (74). The downstream effects of PY-STAT3 are mediated by cyclin D1 (cell cycle regulator), survivin and B-cell lymphoma-extra large (Bcl-xL) (antiapoptotic factors), all reported to be upregulated in PH.…”

Section: Caveolae and Caveolin-1mentioning

confidence: 99%

Pathogenesis of pulmonary hypertension: a case for caveolin-1 and cell membrane integrity

Mathew

2014

American Journal of Physiology-Heart and Circulatory Physiology

View full text Add to dashboard Cite

Mathew R. Pathogenesis of pulmonary hypertension: a case for caveolin-1 and cell membrane integrity. Am J Physiol Heart Circ Physiol 306: H15-H25, 2014. First published October 25, 2013 doi:10.1152/ajpheart.00266.2013.-Pulmonary hypertension (PH) is a progressive disease with a high morbidity and mortality rate. Despite important advances in the field, the precise mechanisms leading to PH are not yet understood. Main features of PH are loss of vasodilatory response, the activation of proliferative and antiapoptotic pathways leading to pulmonary vascular remodeling and obstruction, elevated pressure and right ventricular hypertrophy, resulting in right ventricular failure and death. Experimental studies suggest that endothelial dysfunction may be the key underlying feature in PH. Caveolin-1, a major protein constituent of caveolae, interacts with several signaling molecules including the ones implicated in PH and modulates them. Disruption and progressive loss of endothelial caveolin-1 with reciprocal activation of proliferative pathways occur before the onset of PH, and the rescue of caveolin-1 inhibits proliferative pathways and attenuates PH. Extensive endothelial damage/loss occurs during the progression of the disease with subsequent enhanced expression of caveolin-1 in smooth muscle cells. This caveolin-1 in smooth muscle cells switches from being an antiproliferative factor to a proproliferative one and participates in cell proliferation and cell migration, possibly leading to irreversible PH. In contrast, the disruption of endothelial caveolin-1 is not observed in the hypoxia-induced PH, a reversible form of PH. However, proliferative pathways are activated in this model, indicating caveolin-1 dysfunction. Thus disruption or dysfunction of endothelial caveolin-1 leads to PH, and the status of caveolin-1 may determine the reversibility versus irreversibility of PH. This article reviews the role of caveolin-1 and cell membrane integrity in the pathogenesis and progression of PH.caveolin-1; endothelial cells; pulmonary hypertension; smooth muscle cells THIS ARTICLE is part of a collection on Pathophysiology of Hypertension. Other articles appearing in this collection, as well as a full archive of all collections, can be found online at http://ajpheart.physiology.org/.In 1891, Ernst von Romberg, a German physician, described histological changes in pulmonary hypertension (PH) as pulmonary vascular sclerosis (30). Since then remarkable advances have been made in the understanding of PH, but the pathogenesis of PH still remains elusive, partly because a number of diseases can lead to PH and multiple signaling pathways are implicated in PH. Furthermore, not all signaling pathways are activated in a given patient, and their activation may depend on the stage of the disease. Experimental data suggest that the vascular changes occur before the onset of PH (47,48). Therefore, it is not surprising that by the time the diagnosis of PH is made, most patients have significant pathological changes in pulmonary vasculatu...

show abstract

“…Similar results were recently obtained with cultured endothelial cells isolated form patients with IPAH. These cells have greater proliferation rate and decreased apoptosis, higher level of phosphorylated STAT3 and increased expression of its downstream prosurvival target, Mcl-1 [55]. Moreover, endothelial cells from idiopathic PAH lungs have decreased mitochondria and use preferentially the glycolytic pathway to generate energy, properties in common to cancer cells [56].…”

Section: Hypoxia Signaling In the Lungmentioning

confidence: 99%

Hypoxia and chronic lung disease

et al. 2007

View full text Add to dashboard Cite

The lung is both the conduit for oxygen uptake and is also affected by hypoxia and hypoxia signaling. Decreased ventilatory drive, airway obstructive processes, intra-alveolar exudates, septal thickening by edema, inflammation, fibrosis, or damage to alveolar capillaries will all interpose a significant and potentially life-threatening barrier to proper oxygenation, therefore enhancing the alveolar/arterial pO 2 gradient. These processes result in decreased blood and tissue oxygenation. This review addresses the relationship of hypoxia with lung development and with lung diseases. We particularly focus on molecular mechanisms underlying hypoxia-driven physiological and pathophysiological lung processes, specifically in the infant lung, pulmonary hypertension, and chronic obstructive pulmonary disease.Keywords Hypoxia . Lung . Pathology . HIF Air, containing oxygen at approximately 21% partial pressure at sea level (140-150 mmHg), travels through up to 20 generations of airways by mass flow and then diffuses into the gas exchange units (alveoli) in the lung with a partial pressure of approximately 105-110 mmHg. The human lung contains approximately 480 million alveoli, which represent 64% of total lung structure. These alveoli are elegantly packed in only 1.3-2.6 L of total lung volume, providing a surface area of 120-150 m 2 , equivalent to the dimensions of a "tennis court" dedicated for gas exchange. Although the molecular determinants of lung size are not known, oxygen diffusion constant and gas exchange surface area are roughly proportional to body weight and oxygen consumption in different species [1]. Physical hyperactivity and exposure to a cold environment or high altitude lead to increased oxygen diffusion capacity, in proportion to enhanced oxygen consumption [1].Decreased ventilatory drive, airway obstructive processes, intraalveolar exudates, septal thickening by edema, inflammation, fibrosis, or damage to alveolar capillaries will all interpose a significant and potentially life-threatening barrier to proper oxygenation, therefore enhancing the alveolar/ arterial pO 2 gradient. This review addresses the contribution of hypoxia to lung diseases and the potential molecular mechanisms involved in hypoxia-driven physiological and pathophysiological lung processes (Fig. 1), particularly in the infant lung, pulmonary hypertension, and chronic obstructive pulmonary disease. The fundamental concepts underlying hypoxia-induced gene expression and the molecular regulation of HIF(s) also apply to the lung, and they will be cited in relation to their demonstrated role in lung physiology or pathophysiology.

show abstract

Hyperproliferative apoptosis-resistant endothelial cells in idiopathic pulmonary arterial hypertension

Cited by 326 publications

References 38 publications

Cytoplasmic provenance of STAT3 and PY-STAT3 in the endolysosomal compartments in pulmonary arterial endothelial and smooth muscle cells: implications in pulmonary arterial hypertension

Cytoplasmic provenance of STAT3 and PY-STAT3 in the endolysosomal compartments in pulmonary arterial endothelial and smooth muscle cells: implications in pulmonary arterial hypertension

Pathogenesis of pulmonary hypertension: a case for caveolin-1 and cell membrane integrity

Hypoxia and chronic lung disease

Contact Info

Product

Resources

About