Arachidonate-regulated Ca2+ influx in human airway smooth muscle

Michael A. Thompson, Y.s. Prakash, Christina M Pabelick

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

Plasma membrane Ca2+ influx, especially store-operated Ca 2+ entry triggered by sarcoplasmic reticulum (SR) Ca2+ release, is a key component of intracellular calcium concentration ([Ca 2+]i) regulation in airway smooth muscle (ASM). Agonist-induced Ca2+ oscillations in ASM that involve both influx and SR mechanisms have been previously demonstrated. In nonexcitable cells, [Ca2+]i oscillations involve Ca2+ influx via arachidonic acid (AA) -stimulated channels, which show similarities to store-operated Ca2+ entry, although their molecular identity remains undetermined. Little is known about AA-regulated Ca2+ channels or their regulation in ASM. In enzymatically dissociated human ASM cells loaded with the Ca2+ indicator, fura-2, AA (1-10 μM) triggered [Ca 2+]i oscillations that were inhibited by removal of extracellular Ca2+. Other fatty acids, such as the diacylglycerol analog, 1-oleoyl-2-acetyl-SN-glycerol, oleic acid, and palmitic acid (10 μM each), failed to elicit similar [Ca2+]i responses. Preincubation with LaCl3 (1 μM or 1 mM) inhibited AA-induced oscillations. Inhibition of receptor-operated channels (SKF96,365 [10 μM]), lipoxygenase (zileuton [10 μM]), or cyclooxygenase (indomethacin [10 μM]) did not affect oscillation parameters. Inhibition of SR Ca2+ release (ryanodine [10 μM] or inositol 1,4,5-trisphosphate receptor inhibitor, xestospongin C [1 μM]) decreased [Ca2+]i oscillation frequency and amplitude. Small interfering RNA against caveolin-1, stromal interaction molecule 1, or Orai3 (20 nM each) reduced the frequency and amplitude of AA-induced [Ca2+]i oscillations. In ASM cells derived from individuals with asthma, AA increased oscillation amplitude, but not frequency. These results are highly suggestive of a novel AA-mediated Ca2+-regulatory mechanism in human ASM, reminiscent of agonist-induced oscillations. Given the role of AA in ASM intracellular signaling, especially with inflammation, AA-regulated Ca2+ channels could potentially contribute to increased [Ca2+]i in diseases such asthma.

Original languageEnglish (US)
Pages (from-to)68-76
Number of pages9
JournalAmerican Journal of Respiratory Cell and Molecular Biology
Volume51
Issue number1
DOIs
StatePublished - 2014

Fingerprint

Arachidonic Acid
Smooth Muscle
Muscle
Sarcoplasmic Reticulum
zileuton
Smooth Muscle Myocytes
Asthma
Inositol 1,4,5-Trisphosphate Receptors
Caveolin 1
Ryanodine
Lipoxygenase
Palmitic Acid
Fura-2
Diglycerides
Cell membranes
Oleic Acid
Prostaglandin-Endoperoxide Synthases
Indomethacin
Glycerol
Small Interfering RNA

Keywords

  • Arachidonic acid
  • Bronchial smooth muscle
  • Calcium
  • Influx
  • Sarcoplasmic reticulum

ASJC Scopus subject areas

  • Cell Biology
  • Pulmonary and Respiratory Medicine
  • Molecular Biology
  • Clinical Biochemistry

Cite this

Arachidonate-regulated Ca2+ influx in human airway smooth muscle. / Thompson, Michael A.; Prakash, Y.s.; Pabelick, Christina M.

In: American Journal of Respiratory Cell and Molecular Biology, Vol. 51, No. 1, 2014, p. 68-76.

Research output: Contribution to journalArticle

@article{ab974062850c471c98b805a5f9b464d6,
title = "Arachidonate-regulated Ca2+ influx in human airway smooth muscle",
abstract = "Plasma membrane Ca2+ influx, especially store-operated Ca 2+ entry triggered by sarcoplasmic reticulum (SR) Ca2+ release, is a key component of intracellular calcium concentration ([Ca 2+]i) regulation in airway smooth muscle (ASM). Agonist-induced Ca2+ oscillations in ASM that involve both influx and SR mechanisms have been previously demonstrated. In nonexcitable cells, [Ca2+]i oscillations involve Ca2+ influx via arachidonic acid (AA) -stimulated channels, which show similarities to store-operated Ca2+ entry, although their molecular identity remains undetermined. Little is known about AA-regulated Ca2+ channels or their regulation in ASM. In enzymatically dissociated human ASM cells loaded with the Ca2+ indicator, fura-2, AA (1-10 μM) triggered [Ca 2+]i oscillations that were inhibited by removal of extracellular Ca2+. Other fatty acids, such as the diacylglycerol analog, 1-oleoyl-2-acetyl-SN-glycerol, oleic acid, and palmitic acid (10 μM each), failed to elicit similar [Ca2+]i responses. Preincubation with LaCl3 (1 μM or 1 mM) inhibited AA-induced oscillations. Inhibition of receptor-operated channels (SKF96,365 [10 μM]), lipoxygenase (zileuton [10 μM]), or cyclooxygenase (indomethacin [10 μM]) did not affect oscillation parameters. Inhibition of SR Ca2+ release (ryanodine [10 μM] or inositol 1,4,5-trisphosphate receptor inhibitor, xestospongin C [1 μM]) decreased [Ca2+]i oscillation frequency and amplitude. Small interfering RNA against caveolin-1, stromal interaction molecule 1, or Orai3 (20 nM each) reduced the frequency and amplitude of AA-induced [Ca2+]i oscillations. In ASM cells derived from individuals with asthma, AA increased oscillation amplitude, but not frequency. These results are highly suggestive of a novel AA-mediated Ca2+-regulatory mechanism in human ASM, reminiscent of agonist-induced oscillations. Given the role of AA in ASM intracellular signaling, especially with inflammation, AA-regulated Ca2+ channels could potentially contribute to increased [Ca2+]i in diseases such asthma.",
keywords = "Arachidonic acid, Bronchial smooth muscle, Calcium, Influx, Sarcoplasmic reticulum",
author = "Thompson, {Michael A.} and Y.s. Prakash and Pabelick, {Christina M}",
year = "2014",
doi = "10.1165/rcmb.2013-0144OC",
language = "English (US)",
volume = "51",
pages = "68--76",
journal = "American Journal of Respiratory Cell and Molecular Biology",
issn = "1044-1549",
publisher = "American Thoracic Society",
number = "1",

}

TY - JOUR

T1 - Arachidonate-regulated Ca2+ influx in human airway smooth muscle

AU - Thompson, Michael A.

AU - Prakash, Y.s.

AU - Pabelick, Christina M

PY - 2014

Y1 - 2014

N2 - Plasma membrane Ca2+ influx, especially store-operated Ca 2+ entry triggered by sarcoplasmic reticulum (SR) Ca2+ release, is a key component of intracellular calcium concentration ([Ca 2+]i) regulation in airway smooth muscle (ASM). Agonist-induced Ca2+ oscillations in ASM that involve both influx and SR mechanisms have been previously demonstrated. In nonexcitable cells, [Ca2+]i oscillations involve Ca2+ influx via arachidonic acid (AA) -stimulated channels, which show similarities to store-operated Ca2+ entry, although their molecular identity remains undetermined. Little is known about AA-regulated Ca2+ channels or their regulation in ASM. In enzymatically dissociated human ASM cells loaded with the Ca2+ indicator, fura-2, AA (1-10 μM) triggered [Ca 2+]i oscillations that were inhibited by removal of extracellular Ca2+. Other fatty acids, such as the diacylglycerol analog, 1-oleoyl-2-acetyl-SN-glycerol, oleic acid, and palmitic acid (10 μM each), failed to elicit similar [Ca2+]i responses. Preincubation with LaCl3 (1 μM or 1 mM) inhibited AA-induced oscillations. Inhibition of receptor-operated channels (SKF96,365 [10 μM]), lipoxygenase (zileuton [10 μM]), or cyclooxygenase (indomethacin [10 μM]) did not affect oscillation parameters. Inhibition of SR Ca2+ release (ryanodine [10 μM] or inositol 1,4,5-trisphosphate receptor inhibitor, xestospongin C [1 μM]) decreased [Ca2+]i oscillation frequency and amplitude. Small interfering RNA against caveolin-1, stromal interaction molecule 1, or Orai3 (20 nM each) reduced the frequency and amplitude of AA-induced [Ca2+]i oscillations. In ASM cells derived from individuals with asthma, AA increased oscillation amplitude, but not frequency. These results are highly suggestive of a novel AA-mediated Ca2+-regulatory mechanism in human ASM, reminiscent of agonist-induced oscillations. Given the role of AA in ASM intracellular signaling, especially with inflammation, AA-regulated Ca2+ channels could potentially contribute to increased [Ca2+]i in diseases such asthma.

AB - Plasma membrane Ca2+ influx, especially store-operated Ca 2+ entry triggered by sarcoplasmic reticulum (SR) Ca2+ release, is a key component of intracellular calcium concentration ([Ca 2+]i) regulation in airway smooth muscle (ASM). Agonist-induced Ca2+ oscillations in ASM that involve both influx and SR mechanisms have been previously demonstrated. In nonexcitable cells, [Ca2+]i oscillations involve Ca2+ influx via arachidonic acid (AA) -stimulated channels, which show similarities to store-operated Ca2+ entry, although their molecular identity remains undetermined. Little is known about AA-regulated Ca2+ channels or their regulation in ASM. In enzymatically dissociated human ASM cells loaded with the Ca2+ indicator, fura-2, AA (1-10 μM) triggered [Ca 2+]i oscillations that were inhibited by removal of extracellular Ca2+. Other fatty acids, such as the diacylglycerol analog, 1-oleoyl-2-acetyl-SN-glycerol, oleic acid, and palmitic acid (10 μM each), failed to elicit similar [Ca2+]i responses. Preincubation with LaCl3 (1 μM or 1 mM) inhibited AA-induced oscillations. Inhibition of receptor-operated channels (SKF96,365 [10 μM]), lipoxygenase (zileuton [10 μM]), or cyclooxygenase (indomethacin [10 μM]) did not affect oscillation parameters. Inhibition of SR Ca2+ release (ryanodine [10 μM] or inositol 1,4,5-trisphosphate receptor inhibitor, xestospongin C [1 μM]) decreased [Ca2+]i oscillation frequency and amplitude. Small interfering RNA against caveolin-1, stromal interaction molecule 1, or Orai3 (20 nM each) reduced the frequency and amplitude of AA-induced [Ca2+]i oscillations. In ASM cells derived from individuals with asthma, AA increased oscillation amplitude, but not frequency. These results are highly suggestive of a novel AA-mediated Ca2+-regulatory mechanism in human ASM, reminiscent of agonist-induced oscillations. Given the role of AA in ASM intracellular signaling, especially with inflammation, AA-regulated Ca2+ channels could potentially contribute to increased [Ca2+]i in diseases such asthma.

KW - Arachidonic acid

KW - Bronchial smooth muscle

KW - Calcium

KW - Influx

KW - Sarcoplasmic reticulum

UR - http://www.scopus.com/inward/record.url?scp=84903719251&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84903719251&partnerID=8YFLogxK

U2 - 10.1165/rcmb.2013-0144OC

DO - 10.1165/rcmb.2013-0144OC

M3 - Article

C2 - 24471656

AN - SCOPUS:84903719251

VL - 51

SP - 68

EP - 76

JO - American Journal of Respiratory Cell and Molecular Biology

JF - American Journal of Respiratory Cell and Molecular Biology

SN - 1044-1549

IS - 1

ER -