Role of phospholipase C and tyrosine kinase systems in growth response of human airway smooth muscle cells

1996 ◽  
Vol 270 (5) ◽  
pp. L795-L802 ◽  
Author(s):  
S. De ◽  
E. T. Zelazny ◽  
J. F. Souhrada ◽  
M. Souhrada
Keyword(s):  
Smooth Muscle ◽  
Tyrosine Kinase ◽  
Cell Count ◽  
Phospholipase C ◽  
Airway Smooth Muscle ◽  
Thymidine Incorporation ◽  
Airway Smooth Muscle Cells ◽  
Dependent Manner ◽  
Human Airway Smooth Muscle ◽  
Human Airway

The primary culture of confluent human airway smooth muscle (ASM) cells were exposed up to 5 days to human recombinant interleukin (IL)-1 beta in the presence of indomethacin and 1% fetal bovine serum. The proliferation was assessed by a [3H]thymidine incorporation and direct cell count. We found that IL-1 beta significantly increased thymidine incorporation into and cell count of ASM cells in a concentration-dependent manner. Pretreatment of cells with specific polyclonal antibodies against platelet-derived growth factor (PDGF-BB homodimer) completely inhibited the IL-1 beta-induced increase in thymidine incorporation. The PDGF-BB, at the concentrations of 1.5 and 2.5 ng/ml, stimulated the proliferation of ASM cells. The proliferation action of IL-1 beta was potentiated when PDGF-BB was added into the medium in combination with IL-1 beta. Pretreatment of cells with genistein (0.37 microM), a specific tyrosine kinase inhibitor, attenuated the proliferative effect of IL-1 beta and PDGF-BB. To clarify whether these growth stimuli (IL-1 beta and PDGF-BB) activated phospholipase C (PLC), we examined the formation of phosphatidylinositols. We observed that both agents significantly increased phosphoinositide turnover. In contrast, genistein pretreatment (0.37 microM) prevented formation of inositol 1,4,5-trisphosphate (IP3), as induced by IL-1 beta and/or PDGF-BB. This study demonstrates that both IL-1 beta and PDGF-BB could induce proliferation of ASM cells through the activation of tyrosine kinase and PLC, which in turn stimulate the formation of IP3, a second messenger molecule.

TGF-β1 stimulates IL-8 release, COX-2 expression, and PGE2release in human airway smooth muscle cells

2000 ◽  
Vol 279 (1) ◽  
pp. L201-L207 ◽  
Author(s):  
Choong Yi Fong ◽  
Linhua Pang ◽  
Elaine Holland ◽  
Alan J. Knox
Keyword(s):  
Smooth Muscle ◽  
Airway Smooth Muscle ◽  
Transforming Growth Factor ◽  
Airway Smooth Muscle Cells ◽  
Dependent Manner ◽  
Human Airway Smooth Muscle ◽  
Human Airway ◽  
Cox Inhibitor ◽  
Cox 2 ◽  
Tgf Β1

We have recently shown that endogenous prostanoids are critical in bradykinin-stimulated interleukin (IL)-8 release from human airway smooth muscle (ASM) cells. In this study, we tested the ability of transforming growth factor (TGF)-β1 to stimulate IL-8 release, cyclooxygenase (COX)-2 expression and PGE2 generation in cultured human ASM cells and explored the role of COX products and COX-2 induction on IL-8 release. TGF-β1 stimulated IL-8 release, COX-2 induction, and PGE2 generation in a concentration- and time-dependent manner. Maximal IL-8 release was achieved with 10 ng/ml of TGF-β1 after 16 h of incubation, which was inhibited by the transcription inhibitor actinomycin D and the corticosteroid dexamethasone but was not affected by the nonselective COX inhibitor indomethacin and the selective COX-2 inhibitor NS-398 despite their inhibition on TGF-β1-induced PGE2 release. These results show for the first time that TGF-β1 stimulates IL-8 release, COX-2 induction, and PGE2 generation in human ASM cells and that PGE2 generation is not critical for TGF-β1-induced IL-8 release. These findings suggest that TGF-β1 may play an important role in the pathophysiology of asthma.

Role of ERK MAP kinases in responses of cultured human airway smooth muscle cells to IL-1β

1999 ◽  
Vol 277 (5) ◽  
pp. L943-L951 ◽  
Author(s):  
Johanne D. Laporte ◽  
Paul E. Moore ◽  
Joseph H. Abraham ◽  
Geoffrey N. Maksym ◽  
Ben Fabry ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Airway Smooth Muscle ◽  
Muscle Cells ◽  
Phospholipase A ◽  
Airway Smooth Muscle Cells ◽  
Dependent Manner ◽  
Human Airway Smooth Muscle ◽  
Human Airway ◽  
Cox 2

We have previously reported that interleukin (IL)-1β causes β-adrenergic hyporesponsiveness in cultured human airway smooth muscle cells by increasing cyclooxygenase-2 (COX-2) expression and prostanoid formation. The purpose of this study was to determine whether extracellular signal-regulated kinases (ERKs) are involved in these events. Levels of phosphorylated ERK (p42 and p44) increased 8.3- and 13-fold, respectively, 15 min after treatment with IL-1β (20 ng/ml) alone. Pretreating cells with the mitogen-activated protein kinase kinase inhibitor PD-98059 or U-126 (2 h before IL-1β treatment) decreased ERK phosphorylation. IL-1β (20 ng/ml for 22 h) alone caused a marked induction of COX-2 and increased basal PGE2 release 28-fold ( P < 0.001). PD-98059 (100 μM) and U-126 (10 μM) each decreased COX-2 expression when administered before IL-1β treatment. In control cells, PD-98059 and U-126 had no effect on basal or arachidonic acid (AA; 10 μM)-stimulated PGE2 release, but both inhibitors caused a significant decrease in bradykinin (BK; 1 μM)-stimulated PGE2 release, consistent with a role for ERK in the activation of phospholipase A2 by BK. In IL-1β-treated cells, prior administration of PD-98059 caused 81, 92 and 40% decreases in basal and BK- and AA-stimulated PGE2 release, respectively ( P < 0.01), whereas administration of PD-98059 20 h after IL-1β resulted in only 38 and 43% decreases in basal and BK-stimulated PGE2release, respectively ( P < 0.02) and had no effect on AA-stimulated PGE2 release. IL-1β attenuated isoproterenol-induced decreases in human airway smooth muscle stiffness as measured by magnetic twisting cytometry, and PD-98059 or U-126 abolished this effect in a concentration-dependent manner. These results are consistent with the hypothesis that ERKs are involved early in the signal transduction pathway through which IL-1β induces PGE2 synthesis and β-adrenergic hyporesponsiveness and that ERKs act by inducing COX-2 and activating phospholipase A2.

Impaired cAMP production in human airway smooth muscle cells by bradykinin: role of cyclooxygenase products

1998 ◽  
Vol 275 (2) ◽  
pp. L322-L329 ◽  
Author(s):  
Linhua Pang ◽  
Elaine Holland ◽  
Alan J. Knox
Keyword(s):  
Smooth Muscle ◽  
Airway Smooth Muscle ◽  
Airway Smooth Muscle Cells ◽  
Dependent Manner ◽  
Human Airway Smooth Muscle ◽  
Human Airway ◽  
Camp Generation ◽  
Cox Inhibitor ◽  
Cox 2

Interleukin (IL)-1β impairs human airway smooth muscle (ASM) cell cAMP responses to isoproterenol (Iso). We investigated if bradykinin (BK) could cause a similar effect and the role of cyclooxygenase (COX) products in this event, since we have recently reported that BK, like IL-1β, also causes COX-2 induction and prostanoid release in human ASM cells. BK pretreatment significantly attenuated Iso-induced cAMP generation in a time- and concentration-dependent manner. cAMP generation by prostaglandin (PG) E2but not by forskolin was also impaired. The COX inhibitor indomethacin completely prevented the impairment, whereas the selective COX-2 inhibitors NS-398 and nimesulide, protein synthesis inhibitors cycloheximide and actinomycin D, and steroid dexamethasone were all partially effective. The impairment was mimicked by the B2agonist [Tyr(Me)8]BK, the Ca2+ionophore A-23187, and PGE2and prevented by the B2antagonist HOE-140, but anti-IL-1β serum was ineffective. The results indicate that BK impairs human ASM cell responses to Iso, and the effect is largely mediated by B2receptor-related COX product release via both COX isoforms and is independent of IL-1β.

scholarly journals Actin depolymerization via the β-adrenoceptor in airway smooth muscle cells: a novel PKA-independent pathway

2001 ◽  
Vol 281 (5) ◽  
pp. C1468-C1476 ◽  
Author(s):  
Carol A. Hirshman ◽  
Defen Zhu ◽  
Reynold A. Panettieri ◽  
Charles W. Emala
Keyword(s):  
Smooth Muscle ◽  
Tyrosine Kinase ◽  
Smooth Muscle Cells ◽  
Airway Smooth Muscle ◽  
Actin Polymerization ◽  
Muscle Cells ◽  
Airway Smooth Muscle Cells ◽  
Human Airway Smooth Muscle ◽  
Actin Depolymerization ◽  
Human Airway

Actin is a major functional and structural cytoskeletal protein that mediates such diverse processes as motility, cytokinesis, contraction, and control of cell shape and polarity. While many extracellular signals are known to mediate actin filament polymerization, considerably less is known about signals that mediate depolymerization of the actin cytoskeleton. Human airway smooth muscle cells were briefly exposed to isoproterenol, forskolin, or the cAMP-dependent protein kinase A (PKA) agonist stimulatory diastereoisomer of adenosine 3′,5′-cyclic monophosphate (Sp-cAMPS). Actin polymerization was measured by concomitant staining of filamentous actin with FITC-phalloidin and globular actin with Texas red DNase I. Isoproterenol, forskolin, or Sp-cAMPS induced actin depolymerization, indicated by a decrease in the intensity of filamentous/globular fluorescent staining. The PKA inhibitor Rp diastereomer of adenosine 3′,5′-cyclic monophosphothioate (Rp-cAMPS) completely inhibited forskolin-stimulated depolymerization, whereas it only partially inhibited isoproterenol-induced depolymerization. The protein tyrosine kinase inhibitors genistein or tyrphostin A23 also partially inhibited isoproterenol-induced actin depolymerization. In contrast, the combination of Rp-cAMPS and either tyrosine kinase inhibitor had an additive effect at inhibiting isoproterenol-induced actin depolymerization. These results suggest that both PKA-dependent and -independent pathways mediate actin depolymerization in human airway smooth muscle cells.

Bradykinin activates calcium-dependent potassium channels in cultured human airway smooth muscle cells

2007 ◽  
Vol 292 (4) ◽  
pp. L898-L907 ◽  
Author(s):  
Bo Liu ◽  
Anette M. Freyer ◽  
Ian P. Hall
Keyword(s):  
Smooth Muscle ◽  
Potassium Channels ◽  
Airway Smooth Muscle ◽  
Inositol Phosphate ◽  
Outward Current ◽  
Airway Smooth Muscle Cells ◽  
Dependent Manner ◽  
Human Airway Smooth Muscle ◽  
Early Passage ◽  
Human Airway

Bradykinin (BK) is an inflammatory mediator that can cause bronchoconstriction. In this study, we investigated the membrane currents induced by BK in cultured human airway smooth muscle (ASM) cells. Depolarization of the cells induced outward currents, which were inhibited by tetraethylammonium (TEA) in a concentration-dependent manner with an IC50 of 0.33 μM. The currents were increased by elevating intracellular free Ca2+ concentration, suggesting they are calcium-activated potassium channels [ IK(Ca)]. Preexposure to inhibitor of IK(Ca) of large conductance (BKCa), iberiotoxin, and small conductance (SKCa), apamin, inhibited the increase of outward current induced by BK. The relative contribution of BKCa was greatest in early passage cells. Both nickel and SKF-96365 (10 μM) inhibited the increase of the IK(Ca) induced by BK; however, the l-type Ca2+ channel blocker, nifedipine, had no effect. Activation of the BK-induced current was inhibited by heparin, indicating dependence on intact inositol 1,4,5-triphosphate (IP3)-sensitive intracellular Ca2+ stores. BK also increased inositol phosphate accumulation and induced a transient Ca2+-activated chloride current (CACC) and a sustained nonselective cation current ( ICAT). In summary, BK activates BKCa, SKCa, CACC, and ICAT via IP3-sensitive stores in human ASM.

Functional TRPV4 channels are expressed in human airway smooth muscle cells

2004 ◽  
Vol 287 (2) ◽  
pp. L272-L278 ◽  
Author(s):  
Yanlin Jia ◽  
Xin Wang ◽  
LoriAnn Varty ◽  
Charles A. Rizzo ◽  
Richard Yang ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Airway Smooth Muscle ◽  
Transient Receptor Potential ◽  
Muscle Cells ◽  
Ruthenium Red ◽  
Airway Smooth Muscle Cells ◽  
Dependent Manner ◽  
Human Airway Smooth Muscle ◽  
Human Airway

Hypotonic stimulation induces airway constriction in normal and asthmatic airways. However, the osmolarity sensor in the airway has not been characterized. TRPV4 (also known as VR-OAC, VRL-2, TRP12, OTRPC4), an osmotic-sensitive cation channel in the transient receptor potential (TRP) channel family, was recently cloned. In the present study, we show that TRPV4 mRNA was expressed in cultured human airway smooth muscle cells as analyzed by RT-PCR. Hypotonic stimulation induced Ca2+influx in human airway smooth muscle cells in an osmolarity-dependent manner, consistent with the reported biological activity of TRPV4 in transfected cells. In cultured muscle cells, 4α-phorbol 12,13-didecanoate (4-αPDD), a TRPV4 ligand, increased intracellular Ca2+level only when Ca2+was present in the extracellular solution. The 4-αPDD-induced Ca2+response was inhibited by ruthenium red (1 μM), a known TRPV4 inhibitor, but not by capsazepine (1 μM), a TRPV1 antagonist, indicating that 4-αPDD-induced Ca2+response is mediated by TRPV4. Verapamil (10 μM), an L-type voltage-gated Ca2+channel inhibitor, had no effect on the 4-αPDD-induced Ca2+response, excluding the involvement of L-type Ca2+channels. Furthermore, hypotonic stimulation elicited smooth muscle contraction through a mechanism dependent on membrane Ca2+channels in both isolated human and guinea pig airways. Hypotonicity-induced airway contraction was not inhibited by the L-type Ca2+channel inhibitor nifedipine (1 μM) or by the TRPV1 inhibitor capsazepine (1 μM). We conclude that functional TRPV4 is expressed in human airway smooth muscle cells and may act as an osmolarity sensor in the airway.

Sign in / Sign up

Export Citation Format

Share Document