scholarly journals Hypoxia-induced mitogenic factor/FIZZ1 induces intracellular calcium release through the PLC-IP3 pathway

2009 ◽  
Vol 297 (2) ◽  
pp. L263-L270 ◽  
Author(s):  
Chunling Fan ◽  
Qingning Su ◽  
Yun Li ◽  
Lihua Liang ◽  
Daniel J. Angelini ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Pulmonary Artery ◽  
Calcium Release ◽  
Kinase Inhibitor ◽  
Specific Inhibitor ◽  
Dependent Manner ◽  
Mitogenic Factor ◽  
Intracellular Ca ◽  
Human Pulmonary Artery ◽  
Phosphatidylinositol Phospholipase C

Hypoxia-induced mitogenic factor (HIMF), also known as “found in inflammatory zone 1” (FIZZ1) or resistin-like molecule-α (RELMα), is a profound vasoconstrictor of the pulmonary circulation and a strong mitogenic factor in pulmonary vascular smooth muscle. To further understand the mechanism of these contractile and mitogenic responses, we examined the effect of HIMF on intracellular Ca2+ in human pulmonary artery smooth muscle cells (SMC). Ca2+ imaging in fluo 4-loaded human pulmonary artery SMC revealed that recombinant murine HIMF increased intracellular Ca2+ concentration ([Ca2+]i) in a sustained and oscillatory manner. This increase occurred independent of extracellular Ca2+ influx. Pretreatment of human pulmonary artery SMC with U-73122, a specific inhibitor of phosphatidylinositol-phospholipase C (PLC) completely prevented the HIMF-induced Ca2+ signal. The [Ca2+]i increase was also abolished by pretreatment with 2-aminoethoxydiphenyl borate (2-APB), an inositol 1,4,5-trisphosphate (IP3) receptor antagonist. Ryanodine pretreatment did not affect initiation of [Ca2+]i activation or internal release but reduced [Ca2+]i at the plateau phase. Pretreatment with the Gαi-specific inhibitor pertussis toxin and the Gαs-specific inhibitor NF-449 did not block the Ca2+ signal. Knockdown of Gαq/11 expression did not prevent Ca2+ release, but the pattern of Ca2+ release changed from the sustained oscillatory transients with prolonged plateau to a series of short [Ca2+]i transients that return to baseline. However, pretreatment with the tyrosine kinase inhibitor genistein completely inhibited the internal Ca2+ release. These results demonstrate that HIMF can stimulate intracellular Ca2+ release in human pulmonary artery SMC through the PLC signaling pathway in an IP3- and tyrosine phosphorylation-dependent manner and that Gαq/11 protein-coupled receptor and ryanodine receptor contribute to the increase of [Ca2+]i.

scholarly journals Thrombin-mediated increases in cytosolic [Ca2+] involve different mechanisms in human pulmonary artery smooth muscle and endothelial cells

2008 ◽  
Vol 295 (6) ◽  
pp. L1048-L1055 ◽  
Author(s):  
Richard S. Sacks ◽  
Amy L. Firth ◽  
Carmelle V. Remillard ◽  
Negin Agange ◽  
Jocelyn Yau ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Smooth Muscle ◽  
Pulmonary Artery ◽  
Calcium Influx ◽  
Dynamic Balance ◽  
Cyclopiazonic Acid ◽  
Cell Types ◽  
Intracellular Ca ◽  
Pulmonary Artery Smooth Muscle ◽  
Human Pulmonary Artery

Thrombin is a procoagulant inflammatory agonist that can disrupt the endothelium-lumen barrier in the lung by causing contraction of endothelial cells and promote pulmonary cell proliferation. Both contraction and proliferation require increases in cytosolic Ca2+ concentration ([Ca2+]cyt). In this study, we compared the effect of thrombin on Ca2+ signaling in human pulmonary artery smooth muscle (PASMC) and endothelial (PAEC) cells. Thrombin increased the [Ca2+]cyt in both cell types; however, the transient response was significantly higher and recovered quicker in the PASMC, suggesting different mechanisms may contribute to thrombin-mediated increases in [Ca2+]cyt in these cell types. Depletion of intracellular stores with cyclopiazonic acid (CPA) in the absence of extracellular Ca2+ induced calcium transients representative of those observed in response to thrombin in both cell types. Interestingly, CPA pretreatment significantly attenuated thrombin-induced Ca2+ release in PASMC; this attenuation was not apparent in PAEC, indicating that a PAEC-specific mechanism was targeted by thrombin. Treatment with a combination of CPA, caffeine, and ryanodine also failed to abolish the thrombin-induced Ca2+ transient in PAEC. Notably, thrombin-induced receptor-mediated calcium influx was still observed in PASMC after CPA pretreatment in the presence of extracellular Ca2+. Ca2+ oscillations were triggered by thrombin in PASMC resulting from a balance of extracellular Ca2+ influx and Ca2+ reuptake by the sarcoplasmic reticulum. The data show that thrombin induces increases in intracellular calcium in PASMC and PAEC with a distinct CPA-, caffeine-, and ryanodine-insensitive release existing only in PAEC. Furthermore, a dynamic balance between Ca2+ influx, intracellular Ca2+ release, and reuptake underlie the Ca2+ transients evoked by thrombin in some PASMC. Understanding of such mechanisms will provide an important insight into thrombin-mediated vascular injury during hypertension.

scholarly journals Thymic Stromal Lymphopoietin Promotes Proliferation and Contractility of Human Pulmonary Artery Smooth Muscle

2018 ◽  
Author(s):  
Michael Thompson ◽  
Venkatachalem Sathish ◽  
Logan Manlove ◽  
Benjamin Roos ◽  
Bowen Wang ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Pulmonary Artery ◽  
Vascular Diseases ◽  
Thymic Stromal Lymphopoietin ◽  
Chronic Obstructive ◽  
Obstructive Pulmonary Disease ◽  
Functional Changes ◽  
Intracellular Ca ◽  
Human Pulmonary Artery ◽  
Inflammatory Changes

AbstractHypoxia is a well-recognized risk factor in several pulmonary vascular diseases including pulmonary hypertension (PH). Furthermore, hypoxia-associated inflammatory changes enhance the structural and functional changes in the pulmonary artery (PA) of PH patients. Understanding the mechanisms that link hypoxia and inflammation, particularly early in disease, is key to development of novel therapeutic avenues for PH. Thymic stromal lymphopoietin (TSLP) is an “early” inflammatory mediator thought to be critical in diseases such as asthma, chronic obstructive pulmonary disease and atopic dermatitis. TSLP has canonical effects on the immune system, but can also have non-canonical effects on resident lung cells, e.g. airway smooth muscle. Currently, the expression and role of TSLP in the PA is unknown. We hypothesized that locally-produced TSLP potentiates the effects of hypoxia in PA remodeling and contractility relevant to PH. Experiments in human PA endothelial cells (PAECs) and smooth muscle cells (PASMCs) found PAECs to be a larger source of TSLP which targets PASMCs to enhance intracellular Ca2+ responses to vasoconstrictor agonist as well as cell proliferation, acting via a number of signaling cascades including Stat3 and PI3/Akt. Hypoxia, acting via HIF1α, enhanced PAEC production of TSLP, and promoted TSLP effects on PASMCs. Interestingly, TSLP per se enhance HIF1a. Overall, these novel data highlight a role for TSLP in hypoxia effects on the PA, and thus relevance for inflammation in PH.

scholarly journals Histamine-mediated increases in cytosolic [Ca2+] involve different mechanisms in human pulmonary artery smooth muscle and endothelial cells

2006 ◽  
Vol 290 (2) ◽  
pp. C325-C336 ◽  
Author(s):  
Joseph R. H. Mauban ◽  
Katherine Wilkinson ◽  
Christian Schach ◽  
Jason X.-J. Yuan
Keyword(s):  
Endothelial Cells ◽  
Smooth Muscle ◽  
Pulmonary Artery ◽  
Solution Treatment ◽  
Cyclopiazonic Acid ◽  
Free Solution ◽  
Intracellular Ca ◽  
Pulmonary Artery Smooth Muscle ◽  
Human Pulmonary Artery ◽  
Stimulation Of

Agonist stimulation of human pulmonary artery smooth muscle cells (PASMC) and endothelial cells (PAEC) with histamine showed similar spatiotemporal patterns of Ca2+ release. Both sustained elevation and oscillatory patterns of changes in cytosolic Ca2+ concentration ([Ca2+]cyt) were observed in the absence of extracellular Ca2+. Capacitative Ca2+ entry (CCE) was induced in PASMC and PAEC by passive depletion of intracellular Ca2+ stores with 10 μM cyclopiazonic acid (CPA; 15–30 min). The pyrazole derivative BTP2 inhibited CPA-activated Ca2+ influx, suggesting that depletion of CPA-sensitive internal stores is sufficient to induce CCE in both PASMC and PAEC. The recourse of histamine-mediated Ca2+ release was examined after exposure of cells to CPA, thapsigargin, caffeine, ryanodine, FCCP, or bafilomycin. In PASMC bathed in Ca2+-free solution, treatment with CPA almost abolished histamine-induced rises in [Ca2+]cyt. In PAEC bathed in Ca2+-free solution, however, treatment with CPA eliminated histamine-induced sustained and oscillatory rises in [Ca2+]cyt but did not affect initial transient increase in [Ca2+]cyt. Furthermore, treatment of PAEC with a combination of CPA (or thapsigargin) and caffeine (and ryanodine), FCCP, or bafilomycin did not abolish histamine-induced transient [Ca2+]cyt increases. These observations indicate that 1) depletion of CPA-sensitive stores is sufficient to cause CCE in both PASMC and PAEC; 2) induction of CCE in PAEC does not require depletion of all internal Ca2+ stores; 3) the histamine-releasable internal stores in PASMC are mainly CPA-sensitive stores; 4) PAEC, in addition to a CPA-sensitive functional pool, contain other stores insensitive to CPA, thapsigargin, caffeine, ryanodine, FCCP, and bafilomycin; and 5) although the CPA-insensitive stores in PAEC may not contribute to CCE, they contribute to histamine-mediated Ca2+ release.

Differential effects of intravenous anesthetics on capacitative calcium entry in human pulmonary artery smooth muscle cells

2008 ◽  
Vol 294 (5) ◽  
pp. L1007-L1012 ◽  
Author(s):  
Mikyung Yang ◽  
Xueqin Ding ◽  
Paul A. Murray
Keyword(s):  
Smooth Muscle ◽  
Pulmonary Artery ◽  
Smooth Muscle Cells ◽  
Signaling Pathways ◽  
Capacitative Calcium Entry ◽  
Intravenous Anesthetics ◽  
Intracellular Ca ◽  
Pulmonary Artery Smooth Muscle ◽  
Human Pulmonary Artery ◽  
Pkc Activation

We assessed the roles of the protein kinase C (PKC) and the tyrosine kinase (TK) signaling pathways in regulating capacitative calcium entry (CCE) in human pulmonary artery smooth muscle cells (PASMCs) and investigated the effects of intravenous anesthetics (midazolam, propofol, thiopental, ketamine, etomidate, morphine, and fentanyl) on CCE in human PASMCs. Fura-2-loaded human PASMCs were placed in a dish (37°C) on an inverted fluorescence microscope. Intracellular Ca2+ concentration ([Ca2+]i) was measured as the 340/380 fluorescence ratio in individual PASMCs. Thapsigargin, a sarcoplasmic reticulum Ca2+-adenosine triphosphatase inhibitor, was used to deplete intracellular Ca2+ stores after removing extracellular Ca2+. CCE was then activated by restoring extracellular Ca2+ (2.2 mM). The effects of PKC activation and inhibition, TK inhibition, and the intravenous anesthetics on CCE were assessed. Thapsigargin caused a transient increase in [Ca2+]i. Restoring extracellular Ca2+ caused a rapid peak increase in [Ca2+]i, followed by a sustained increase in [Ca2+]i; i.e., CCE was stimulated in human PASMCs. PKC activation attenuated ( P < 0.05), whereas PKC inhibition potentiated ( P < 0.05), both peak and sustained CCE. TK inhibition attenuated ( P < 0.05) both peak and sustained CCE. Midazolam, propofol, and thiopental each attenuated ( P < 0.05) both peak and sustained CCE, whereas ketamine, etomidate, morphine, and fentanyl had no effect on CCE. Our results suggest that CCE in human PASMCs is influenced by both the TK and PKC signaling pathways. Midazolam, propofol, and thiopental each attenuated CCE, whereas ketamine, etomidate, morphine, and fentanyl had no effect on CCE.

scholarly journals Fenfluramine-Induced Gene Dysregulation in Human Pulmonary Artery Smooth Muscle and Endothelial Cells

2011 ◽  
Vol 1 (3) ◽  
pp. 405-418 ◽  
Author(s):  
Weijuan Yao ◽  
Wenbo Mu ◽  
Amy Zeifman ◽  
Michelle Lofti ◽  
Carmelle V. Remillard ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Smooth Muscle ◽  
Pulmonary Artery ◽  
Gene Dysregulation ◽  
Pulmonary Artery Smooth Muscle ◽  
Human Pulmonary Artery

Urokinase-induced migration of human vascular smooth muscle cells requires coupling of the small GTPases RhoA and Rac1 to the Tyk2/PI3-K signalling pathway

2003 ◽  
Vol 89 (05) ◽  
pp. 904-914 ◽  
Author(s):  
Natalia Tkachuk ◽  
Hermann Haller ◽  
Inna Dumler ◽  
Ioulia Kiian
Keyword(s):  
Smooth Muscle ◽  
Cell Migration ◽  
Vascular Smooth Muscle ◽  
Kinase Inhibitor ◽  
Rho Kinase ◽  
Small Gtpases ◽  
Janus Kinase ◽  
Immunocytochemical Staining ◽  
Boyden Chamber ◽  
Dependent Manner

SummaryUrokinase-type plasminogen activator (uPA) facilitates cell migration by localizing proteolisys on the cell surface and by inducing intracellular signalling pathways. In human vascular smooth muscle cell (VSMC) uPA stimulates migration via the uPA receptor (uPAR) signalling complex containing the Janus kinase Tyk2 and phosphatidylinositol 3-kinase (PI3-K). We report that active GTP-bound forms of small GTPases RhoA and Rac1, but not Cdc42, are directly associated with Tyk2 and PI3-K in an uPA/uPAR-dependent fashion. Endogenous RhoA, but not Rac1 or Cdc42, was significantly activated in response to uPA. RhoA activation was abolished by cell treatment with two unrelated, structurally distinct, specific inhibitors of PI3-K, wortmannin, and LY294002. Downstream of RhoA, phosphorylation of myosin light chain (MLC) was dramatically upregulated by uPA in a Rho kinase- and PI3-K-dependent manner. Thus, selective Rho kinase inhibitor Y27632 and PI3-K inhibitors wortmannin and LY294002 prevented the uPA-induced stimulation of MLC phosphorylation. Rho kinase inhibition also decreased uPA-stimulated VSMC migration as observed in a Boyden chamber. VSMC immunocytochemical staining demonstrated redistribution of RhoA and Rac1 active forms to the newly formed leading edge of migrating cell. VSMC microinjection with antibodies to either Rho or Rac1 decreased uPA-stimulated cell migration, indicating the involvement of both GTPases in the migration process. Our results provide evidence that the small GTPases RhoA and Rac1, together with Rho kinase, are necessary to mediate the uPA/uPAR-directed migration via the Tyk2/PI3-K signalling complex in human VSMC.

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