Dataset Information

Endothelin-1, the unfolded protein response, and persistent inflammation: role of pulmonary artery smooth muscle cells.

ABSTRACT: Endothelin-1 is a potent vasoactive peptide that occurs in chronically high levels in humans with pulmonary hypertension and in animal models of the disease. Recently, the unfolded protein response was implicated in a variety of diseases, including pulmonary hypertension. In addition, evidence is increasing for pathological, persistent inflammation in the pathobiology of this disease. We investigated whether endothelin-1 might engage the unfolded protein response and thus link inflammation and the production of hyaluronic acid by pulmonary artery smooth muscle cells. Using immunoblot, real-time PCR, immunofluorescence, and luciferase assays, we found that endothelin-1 induces both a transcriptional and posttranslational activation of the three major arms of the unfolded protein response. The pharmacologic blockade of endothelin A receptors, but not endothelin B receptors, attenuated the observed release, as did a pharmacologic blockade of extracellular signal-regulated kinases 1 and 2 (ERK-1/2) signaling. Using short hairpin RNA and ELISA, we observed that the release by pulmonary artery smooth muscle cells of inflammatory modulators, including hyaluronic acid, is associated with endothelin-1-induced ERK-1/2 phosphorylation and the unfolded protein response. Furthermore, the synthesis of hyaluronic acid induced by endothelin-1 is permissive for persistent THP-1 monocyte binding. These results suggest that endothelin-1, in part because it induces the unfolded protein response in pulmonary artery smooth muscle cells, triggers proinflammatory processes that likely contribute to vascular remodeling in pulmonary hypertension.

SUBMITTER: Yeager ME

PROVIDER: S-EPMC3262656 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Endothelin-1, the unfolded protein response, and persistent inflammation: role of pulmonary artery smooth muscle cells.

Yeager Michael E ME Belchenko Dmitry D DD Nguyen Cecilia M CM Colvin Kelley L KL Ivy D Dunbar DD Stenmark K R KR

American journal of respiratory cell and molecular biology 20120101 1

Endothelin-1 is a potent vasoactive peptide that occurs in chronically high levels in humans with pulmonary hypertension and in animal models of the disease. Recently, the unfolded protein response was implicated in a variety of diseases, including pulmonary hypertension. In addition, evidence is increasing for pathological, persistent inflammation in the pathobiology of this disease. We investigated whether endothelin-1 might engage the unfolded protein response and thus link inflammation and t ...[more]

PMID: 21778413

Similar Datasets

Project description:Contraction of human pulmonary artery smooth muscle cells (HPASMC) isolated from pulmonary arterial hypertensive (PAH) and normal (non-PAH) subject lungs was determined and measured with real-time electrical impedance. Treatment of HPASMC with vasoactive peptides, endothelin-1 (ET-1) and bradykinin (BK) but not angiotensin II, induced a temporal decrease in the electrical impedance profile mirroring constrictive morphological change of the cells which typically was more robust in PAH as opposed to non-PAH cells. Inhibition with LIMKi3 and a cofilin targeted motif mimicking cell permeable peptide (MMCPP) had no effect on ET-1 induced HPASMC contraction indicating a negligible role for these actin regulatory proteins. On the other hand, a MMCPP blocking the activity of caldesmon reduced ET-1 promoted contraction pointing to a regulatory role of this protein and its activation pathway in HPASMC contraction. Inhibition of this MEK/ERK/p90RSK pathway, which is an upstream regulator of caldesmon phosphorylation, reduced ET-1 induced cell contraction. While the regulation of ET-1 induced cell contraction was found to be similar in PAH and non-PAH cells, a key difference was the response to pharmacological inhibitors and to siRNA knockdown of Rho kinases (ROCK1/ROCK2). The PAH cells required much higher concentrations of inhibitors to abrogate ET-1 induced contractions and their contraction was not affected by siRNA against either ROCK1 or ROCK2. Lastly, blocking of L-type and T-type Ca2+ channels had no effect on ET-1 or BK induced contraction. However, inhibiting the activity of the sarcoplasmic reticulum Ca2+ ATPase blunted ET-1 and BK induced HPASMC contraction in both PAH and non-PAH derived HPASMC. In summary, our findings here together with previous communications illustrate similarities and differences in the regulation PAH and non-PAH smooth muscle cell contraction relating to calcium translocation, RhoA/ROCK signaling and the activity of caldesmon. These findings may provide useful tools in achieving the regulation of the vascular hypercontractility taking place in PAH.

Project description:The chronic phase of pulmonary arterial hypertension (PAH) is associated with vascular remodeling, especially thickening of the smooth muscle layer of large pulmonary arteries and muscularization of small pulmonary vessels, which normally have no associated smooth muscle. Serotonin (5-hydroxytryptamine, 5-HT) has been shown to induce proliferation and hypertrophy of pulmonary artery smooth muscle cells (PASMC), and may be important for in vivo pulmonary vascular remodeling. Here, we show that 5-HT stimulates migration of pulmonary artery PASMC. Treatment with 5-HT for 16h increased migration of PASMC up to four-fold as monitored in a modified Boyden chamber assay. Increased migratory responses were associated with cellular morphological changes and reorganization of the actin cytoskeleton. 5-HT-induced alterations in morphology were previously shown in our laboratory to require cAMP [Lee SL, Fanburg BL. Serotonin produces a configurational change of cultured smooth muscle cells that is associated with elevation of intracellular cAMP. J Cell Phys 1992;150(2):396-405], and the 5-HT4 receptor was pharmacologically determined to be the primary activator of cAMP in bovine PASMC [Becker BN, Gettys TW, Middleton JP, Olsen CL, Albers FJ, Lee SL, et al. 8-Hydroxy-2-(di-n-propylamino)tetralin-responsive 5-hydroxytryptamine4-like receptor expressed in bovine pulmonary artery smooth muscle cells. Mol Pharmacol 1992;42(5):817-25]. We examined the role of the 5-HT4 receptor and cAMP in 5-HT-induced bovine PASMC migration. PASMC express 5-HT4 receptor mRNA, and a 5-HT4 receptor antagonist and a cAMP antagonist completely blocked 5-HT-induced cellular migration. Consistent with our previous report that a cAMP-dependent Cl(-) channel is required for 5-HT-induced morphological changes in PASMC, phenylanthranilic acid, a Cl(-) channel blocker, inhibited actin cytoskeletal reorganization and migration produced by 5-HT. We conclude that 5-HT stimulates PASMC migration and associated cytoskeletal reorganization through the 5-HT4 receptor and cAMP activation of a chloride channel.

Dataset Information

Endothelin-1, the unfolded protein response, and persistent inflammation: role of pulmonary artery smooth muscle cells.

Publications

Endothelin-1, the unfolded protein response, and persistent inflammation: role of pulmonary artery smooth muscle cells.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets