Elastase-Like Activities of Arterial Smooth Muscle Cells in Cultuhe are Located on the Plasma Membrane

Pulmonary arterial hypertension (PAH) is a rare and lethal disease characterized by vascular remodeling and vasoconstriction, which is associated with increased intracellular calcium ion concentration ([Ca2+]i). Platelet-derived growth factor-BB (PDGF-BB) is the most potent mitogen for pulmonary arterial smooth muscle cells (PASMCs) and is involved in vascular remodeling during PAH development. PDGF signaling has been proved to participate in maintaining Ca2+ homeostasis of PASMCs; however, the mechanism needs to be further elucidated. Here, we illuminate that the expression of plasma membrane calcium-transporting ATPase 4 (PMCA4) was downregulated in PASMCs after PDGF-BB stimulation, which could be abolished by restraining the mitogen-activated protein kinase/extracellular signal-regulated kinase (MEK/ERK). Functionally, suppression of PMCA4 attenuated the [Ca2+]i clearance in PASMCs after Ca2+ entry, promoting cell proliferation and elevating cell locomotion through mediating formation of focal adhesion. Additionally, the expression of PMCA4 was decreased in the pulmonary artery of monocrotaline (MCT)- or hypoxia-induced PAH rats. Moreover, knockdown of PMCA4 could increase the right ventricular systolic pressure (RVSP) and wall thickness (WT) of pulmonary artery in rats raised under normal conditions. Taken together, our findings demonstrate the importance of the PDGF/MEK/ERK/PMCA4 axis in intracellular Ca2+ homeostasis in PASMCs, indicating a functional role of PMCA4 in pulmonary arterial remodeling and PAH development.

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PICK1/calcineurin suppress ASIC1-mediated Ca2+ entry in rat pulmonary arterial smooth muscle cells

AJP Cell Physiology ◽

10.1152/ajpcell.00091.2015 ◽

2016 ◽

Vol 310 (5) ◽

pp. C390-C400 ◽

Cited By ~ 6

Author(s):

Lindsay M. Herbert ◽

Carlos H. Nitta ◽

Tracylyn R. Yellowhair ◽

Carly Browning ◽

Laura V. Gonzalez Bosc ◽

...

Keyword(s):

Smooth Muscle ◽

Plasma Membrane ◽

Smooth Muscle Cells ◽

Muscle Cells ◽

Membrane Localization ◽

Arterial Smooth Muscle ◽

Plasma Membrane Localization ◽

Pulmonary Arterial ◽

Arterial Smooth Muscle Cells ◽

Pulmonary Arterial Smooth Muscle

Acid-sensing ion channel 1 (ASIC1) contributes to Ca2+ influx and contraction in pulmonary arterial smooth muscle cells (PASMC). ASIC1 binds the PDZ (PSD-95/Dlg/ZO-1) domain of the protein interacting with C kinase 1 (PICK1), and this interaction is important for the subcellular localization and/or activity of ASIC1. Therefore, we first hypothesized that PICK1 facilitates ASIC1-dependent Ca2+ influx in PASMC by promoting plasma membrane localization. Using Duolink to determine protein-protein interactions and a biotinylation assay to assess membrane localization, we demonstrated that the PICK1 PDZ domain inhibitor FSC231 diminished the colocalization of PICK1 and ASIC1 but did not limit ASIC1 plasma membrane localization. Although stimulation of store-operated Ca2+ entry (SOCE) greatly enhanced colocalization between ASIC1 and PICK1, both FSC231 and shRNA knockdown of PICK1 largely augmented SOCE. These data suggest PICK1 imparts a basal inhibitory effect on ASIC1 Ca2+ entry in PASMC and led to an alternative hypothesis that PICK1 facilitates the interaction between ASIC1 and negative intracellular modulators, namely PKC and/or the calcium-calmodulin-activated phosphatase calcineurin. FSC231 limited PKC-mediated inhibition of SOCE, supporting a potential role for PICK1 in this response. Additionally, we found PICK1 inhibits ASIC1-mediated SOCE through an effect of calcineurin to dephosphorylate the channel. Furthermore, it appears PICK1/calcineurin-mediated regulation of SOCE opposes PKA phosphorylation and activation of ASIC1. Together our data suggest PKA and PICK1/calcineurin differentially regulate ASIC1-mediated SOCE and these modulatory complexes are important in determining downstream Ca2+ signaling.

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H 2 O 2 decreases ASIC1 plasma membrane localization in rat pulmonary arterial smooth muscle cells (1175.3)

The FASEB Journal ◽

10.1096/fasebj.28.1_supplement.1175.3 ◽

2014 ◽

Vol 28 (S1) ◽

Author(s):

Danielle Plomaritas ◽

Lindsay Herbert ◽

Thomas Resta ◽

Benjimen Walker ◽

Nikki Jernigan

Keyword(s):

Smooth Muscle ◽

Plasma Membrane ◽

Smooth Muscle Cells ◽

Muscle Cells ◽

Membrane Localization ◽

Arterial Smooth Muscle ◽

Plasma Membrane Localization ◽

Pulmonary Arterial ◽

Arterial Smooth Muscle Cells ◽

Pulmonary Arterial Smooth Muscle

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Pathogenesis of arteritis of SL/Ni mice. Possible lytic effect of anti-gp70 antibodies on vascular smooth muscle cells.

Journal of Experimental Medicine ◽

10.1084/jem.166.4.890 ◽

1987 ◽

Vol 166 (4) ◽

pp. 890-908 ◽

Cited By ~ 23

Author(s):

M Miyazawa ◽

M Nose ◽

M Kawashima ◽

M Kyogoku

Keyword(s):

Smooth Muscle ◽

Plasma Membrane ◽

Smooth Muscle Cells ◽

Leukemia Virus ◽

Muscle Cells ◽

Fibroblast Cell ◽

Natural Antibodies ◽

Electron Microscopic ◽

Arterial Smooth Muscle ◽

Arterial Smooth Muscle Cells

The SL/Ni strain of mice spontaneously develops a necrotizing polyarteritis (NPA) that is histologically quite similar to human polyarteritis nodosa. This NPA most frequently affected parametrial tissues and/or ovaries of females and small arterioles of the major salivary glands. Electron microscopic studies of early arterial lesions revealed massive budding of C-type particles from arterial smooth muscle cells just before or at the onset of arteritis. In addition, binding of mouse IgG and C3 to the plasma membrane of virus-producing smooth muscle cells was shown by immunoelectron microscopy. Antibody-bound muscle cells showed disintegration of their plasma membrane, but degeneration and necrosis of muscle cells were not associated with dense infiltration of neutrophils. SL/Ni mice had natural antibodies that bound specifically to a fibroblast cell line infected with an endogenous ecotropic murine leukemia virus (MuLV) recovered from a SL/Ni mouse. Most of the natural antibodies were cytotoxic in the presence of murine complement. Western blot immunoassays revealed that among 14 SL/Ni female mice tested, all of the 9 mice that were affected by arteritis had anti-gp70 antibodies, while the 3 anti-gp70- mice were not affected. The presence of anti-p30 or anti-p15 (anti-p12) antibodies, which were also detected in some SL/Ni mice, did not correlate with the development of arteritis. These results strongly support the hypothesis that NPA in SL/Ni mice is mediated by the lysis of arterial smooth muscle cells due to the deposition of cytotoxic natural antibodies directed to cell membrane-bound gp70 molecules of an endogenous ecotropic MuLV.

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