scholarly journals Phenotype transitions induced by mechanical stimuli in airway smooth muscle are regulated by differential interactions of parvin isoforms with paxillin and Akt

2020 ◽  
Vol 318 (5) ◽  
pp. L1036-L1055 ◽  
Author(s):  
Youliang Huang ◽  
Susan J. Gunst
Keyword(s):  
Smooth Muscle ◽  
Airway Smooth Muscle ◽  
Mechanical Stimuli ◽  
Akt Activation ◽  
High Tension ◽  
Inflammatory Phenotype ◽  
Inflammatory State ◽  
Differentiation Marker ◽  
Low Tension ◽  
Phenotype Expression

Mechanical tension and humoral stimuli can induce transitions in airway smooth muscle phenotype between a synthetic inflammatory state that promotes cytokine secretion and a differentiated state that promotes the expression of smooth muscle phenotype-specific proteins. When tissues are maintained under high tension, Akt activation and eotaxin secretion are suppressed, but expression of the differentiation marker protein, smooth muscle myosin heavy chain (SmMHC), is promoted. When tissues are maintained under low tension, Akt activation and eotaxin secretion are stimulated, and the differentiated phenotype is suppressed. We hypothesized that mechanical stimuli are differentially transduced to Akt-mediated signaling pathways that regulate phenotype expression by α-parvin and β-parvin integrin-linked kinase/PINCH/parvin (IPP) signaling complexes within integrin adhesomes. High tension or ACh triggered paxillin phosphorylation and the binding of phospho-paxillin to β-parvin IPP complexes. This inhibited Akt activation and promoted SmMHC expression. Low tension or IL-4 did not elicit paxillin phosphorylation and triggered the binding of unphosphorylated paxillin to α-parvin IPP complexes, which promoted Akt activation and eotaxin secretion and suppressed SmMHC expression. Expression of a nonphosphorylatable paxillin mutant or β-parvin depletion by siRNA promoted the inflammatory phenotype, whereas the depletion of α-parvin promoted the differentiated phenotype. Results demonstrate that phenotype expression is regulated by the differential interaction of phosphorylated and unphosphorylated paxillin with α-parvin and β-parvin IPP complexes and that these complexes have opposite effects on the activation of Akt. Our results describe a novel molecular mechanism for transduction of mechanical and humoral stimuli within integrin signaling complexes to regulate phenotype expression in airway smooth muscle.

scholarly journals Focal adhesion kinase (FAK) and mechanical stimulation negatively regulate the transition of airway smooth muscle tissues to a synthetic phenotype

2016 ◽  
Vol 311 (5) ◽  
pp. L893-L902 ◽  
Author(s):  
Yidi Wu ◽  
Youliang Huang ◽  
Susan J. Gunst
Keyword(s):  
Smooth Muscle ◽  
Focal Adhesion Kinase ◽  
Airway Smooth Muscle ◽  
Focal Adhesion ◽  
Inflammatory Responses ◽  
Mechanical Load ◽  
Akt Activation ◽  
Lower Load ◽  
Synthetic Phenotype

The effects of mechanical forces and focal adhesion kinase (FAK) in regulating the inflammatory responses of airway smooth muscle (ASM) tissues to stimulation with interleukin (IL)-13 were investigated. Canine tracheal tissues were subjected to different mechanical loads in vitro, and the effects of mechanical load on eotaxin secretion and inflammatory signaling pathways in response to IL-13 were determined. Eotaxin secretion by tissues in response to IL-13 was significantly inhibited in muscles maintained at a higher (+) load compared with those at a lower (−) load as assessed by ELISA, and Akt activation was also reduced in the higher (+) loaded tissues. Conversely the (+) mechanical load increased activation of the focal adhesion proteins FAK and paxillin in the tissues. The role of FAK in regulating the mechanosensitive responses was assessed by overexpressing FAK-related nonkinase in the tissues, by expressing the FAK kinase-dead mutant FAK Y397F, or by treating tissues with the FAK inhibitor PF-573228. FAK inactivation potentiated Akt activity and increased eotaxin secretion in response to IL-13. FAK inhibition also suppressed the mechanosensitivity of Akt activation and eotaxin secretion. In addition, FAK inactivation suppressed smooth muscle myosin heavy chain expression induced by the higher (+) mechanical load. The results demonstrate that the imposition of a higher mechanical load on airway smooth muscle stimulates FAK activation, which promotes the expression of the differentiated contractile phenotype and suppresses the synthetic phenotype and the inflammatory responses of the muscle tissue.

scholarly journals Mechanical stimuli and IL-13 interact at integrin adhesion complexes to regulate expression of smooth muscle myosin heavy chain in airway smooth muscle tissue

2011 ◽  
Vol 301 (3) ◽  
pp. L275-L284 ◽  
Author(s):  
Leena P. Desai ◽  
Yidi Wu ◽  
Robert S. Tepper ◽  
Susan J. Gunst
Keyword(s):  
Smooth Muscle ◽  
Protein Expression ◽  
Airway Smooth Muscle ◽  
Heavy Chain ◽  
High Load ◽  
Phenotypic Marker ◽  
Akt Activation ◽  
Muscle Tissues ◽  
Low Load ◽  
Muscle Myosin

Airway smooth muscle phenotype may be modulated in response to external stimuli under physiological and pathophysiological conditions. The effect of mechanical forces on airway smooth muscle phenotype were evaluated in vitro by suspending weights of 0.5 or 1 g from the ends of canine tracheal smooth muscle tissues, incubating the weighted tissues for 6 h, and then measuring the expression of the phenotypic marker protein, smooth muscle myosin heavy chain (SmMHC). Incubation of the tissues at a high load significantly increased expression of SmMHC compared with incubation at low load. Incubation of the tissues at a high load also decreased activation of PKB/Akt, as indicated by its phosphorylation at Ser 473. Inhibition of Akt or phosphatidylinositol-3,4,5 triphosphate-kinase increased SmMHC expression in tissues at low load but did not affect SmMHC expression at high load. IL-13 induced a significant increase in Akt activation and suppressed the expression of SmMHC protein at both low and high loads. The role of integrin signaling in mechanotransduction was evaluated by expressing a PINCH (LIM1–2) fragment in the muscle tissues that prevents the membrane localization of the integrin-binding IPP complex (ILK/PINCH/α-parvin), and also by expressing an inactive integrin-linked kinase mutant (ILK S343A) that inhibits endogenous ILK activity. Both mutants inhibited Akt activation and increased expression of SmMHC protein at low load but had no effect at high load. These results suggest that mechanical stress and IL-13 both act through an integrin-mediated signaling pathway to oppositely regulate the expression of phenotypic marker proteins in intact airway smooth muscle tissues. The stimulatory effects of mechanical stress on contractile protein expression oppose the suppression of contractile protein expression mediated by IL-13; thus the imposition of mechanical strain may inhibit changes in airway smooth muscle phenotype induced by inflammatory mediators.

The Proprotein Convertase Furin inhibits IL-13 Induced Inflammation in Airway Smooth Muscle by Regulating Integrin Associated Signaling Complexes

2021 ◽  
Author(s):  
Yidi Wu ◽  
Youliang Huang ◽  
Wenwu Zhang ◽  
Susan J. Gunst
Keyword(s):  
Smooth Muscle ◽  
Airway Smooth Muscle ◽  
Inflammatory Responses ◽  
Therapeutic Potential ◽  
Proprotein Convertase ◽  
Akt Activation ◽  
Inflammatory Conditions ◽  
Muscle Tissues ◽  
Muscle Myosin

Furin is a proprotein convertase that regulates the activation and inactivation of multiple proteins including matrix metalloproteinases, integrins and cytokines. It is a serine endoprotease that localizes to the plasma membrane and can be secreted into the extracellular space. The role of furin in regulating inflammation in isolated canine airway smooth muscle tissues was investigated. The treatment of airway tissues with recombinant furin (rFurin) inhibited the activation of Akt and eotaxin secretion induced by IL-13, and it prevented the IL-13 induced suppression of smooth muscle myosin heavy chain expression. rFurin promoted a differentiated phenotype by activating β1 integrin proteins and stimulating the activation of the adhesome proteins vinculin and paxillin by talin. Activated paxillin induced the binding of Akt to β-parvin IPP (ILK, PINCH, parvin) complexes, which inhibits Akt activation. Treatment of tissues with a furin inhibitor or the depletion of endogenous furin using shRNA resulted in Akt activation and inflammatory responses similar to those induced by IL-13. Furin inactivation or IL-13 caused talin cleavage and integrin inactivation, resulting in the inactivation of vinculin and paxillin. Paxillin inactivation resulted in the coupling of Akt to α-parvin IPP complexes, which catalyze Akt activation and an inflammatory response. The results demonstrate that furin inhibits inflammation in airway smooth muscle induced by IL-13, and that the anti-inflammatory effects of furin are mediated by activating integrin proteins and integrin-associated signaling complexes that regulate Akt-mediated pathways to the nucleus. Furin may have therapeutic potential for the treatment of inflammatory conditions of the lungs and airways.

scholarly journals Interleukin-1β modulates smooth muscle cell phenotype to a distinct inflammatory state relative to PDGF-DD via NF-κB-dependent mechanisms

2012 ◽  
Vol 44 (7) ◽  
pp. 417-429 ◽  
Author(s):  
Matthew R. Alexander ◽  
Meera Murgai ◽  
Christopher W. Moehle ◽  
Gary K. Owens
Keyword(s):  
Gene Expression ◽  
Smooth Muscle ◽  
Smooth Muscle Cell ◽  
Marker Gene ◽  
Marker Genes ◽  
Atherosclerotic Plaques ◽  
Phenotypic Modulation ◽  
Marker Gene Expression ◽  
Inflammatory State ◽  
Differentiation Marker

Smooth muscle cell (SMC) phenotypic modulation in atherosclerosis and in response to PDGF in vitro involves repression of differentiation marker genes and increases in SMC proliferation, migration, and matrix synthesis. However, SMCs within atherosclerotic plaques can also express a number of proinflammatory genes, and in cultured SMCs the inflammatory cytokine IL-1β represses SMC marker gene expression and induces inflammatory gene expression. Studies herein tested the hypothesis that IL-1β modulates SMC phenotype to a distinct inflammatory state relative to PDGF-DD. Genome-wide gene expression analysis of IL-1β- or PDGF-DD-treated SMCs revealed that although both stimuli repressed SMC differentiation marker gene expression, IL-1β distinctly induced expression of proinflammatory genes, while PDGF-DD primarily induced genes involved in cell proliferation. Promoters of inflammatory genes distinctly induced by IL-1β exhibited over-representation of NF-κB binding sites, and NF-κB inhibition in SMCs reduced IL-1β-induced upregulation of proinflammatory genes as well as repression of SMC differentiation marker genes. Interestingly, PDGF-DD-induced SMC marker gene repression was not NF-κB dependent. Finally, immunofluorescent staining of mouse atherosclerotic lesions revealed the presence of cells positive for the marker of an IL-1β-stimulated inflammatory SMC, chemokine (C-C motif) ligand 20 (CCL20), but not the PDGF-DD-induced gene, regulator of G protein signaling 17 (RGS17). Results demonstrate that IL-1β- but not PDGF-DD-induced phenotypic modulation of SMC is characterized by NF-κB-dependent activation of proinflammatory genes, suggesting the existence of a distinct inflammatory SMC phenotype. In addition, studies provide evidence for the possible utility of CCL20 and RGS17 as markers of inflammatory and proliferative state SMCs within atherosclerotic plaques in vivo.

Allergen inhalation generates pro-inflammatory oxidised phosphatidylcholine associated with airway dysfunction

2020 ◽  
pp. 2000839 ◽  
Author(s):  
Christopher D. Pascoe ◽  
Aruni Jha ◽  
Min Hyung Ryu ◽  
Mirna Ragheb ◽  
Jignesh Vaghasiya ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Smooth Muscle ◽  
Airway Smooth Muscle ◽  
High Performance ◽  
Allergen Challenge ◽  
Airway Narrowing ◽  
Gm Csf ◽  
Liquid Chromatography Tandem Mass ◽  
Inflammatory Phenotype ◽  
Novel Target

RationaleOxidised phosphatidylcholines (OxPC) are produced under conditions of elevated oxidative stress and can contribute to human disease pathobiology. However, their role in allergic asthma is unexplored.ObjectivesCharacterise the OxPC profile in the airways after allergen challenge of people with airway hyperresponsiveness (AHR) or mild-asthma. Determine the capacity of OxPC to contribute to pathobiology associated with asthma.MethodsUsing bronchoalveolar lavage (BAL) from two human cohorts, OxPC species were quantified using ultra high performance liquid chromatography tandem mass spectrometry. Murine thin cut lung slices (TCLS) were used to measure airway narrowing caused by OxPCs. Human airway smooth muscle (HASM) cells were exposed to OxPCs to assess concentration-associated changes in inflammatory phenotype and activation of signalling networks.Measurements and Main ResultsOxPC profiles were different in the airways of people with or without AHR and correlated with methacholine responsiveness. Exposure of mild-asthmatics to allergens produced unique OxPC signatures that were associated with the late asthma response severity. OxPCs dose-dependently induced 15% airway narrowing in murine TCLS. In HASM, OxPCs dose-dependently increased the biosynthesis of cyclooxygenase-2, IL-6, IL-8, GM-CSF, and the production of oxylipins via protein kinase C-dependent pathways.ConclusionsData from human cohorts and primary HASM culture we show that OxPCs are present in the airways, increase after allergen challenge, and correlate with metrics of a dysfunction. Furthermore, OxPCs may contribute to asthma pathobiology by promoting airway narrowing and inducing a pro-inflammatory phenotype and contraction of airway smooth muscle. OxPCs represent a potential novel target for treating oxidative stress-associated pathobiology in asthma.

scholarly journals Caveolin-1 is required for contractile phenotype expression by airway smooth muscle cells

2011 ◽  
Vol 15 (11) ◽  
pp. 2430-2442 ◽  
Author(s):  
Reinoud Gosens ◽  
Gerald L. Stelmack ◽  
Sophie T. Bos ◽  
Gordon Dueck ◽  
Mark M. Mutawe ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Airway Smooth Muscle ◽  
Muscle Cells ◽  
Airway Smooth Muscle Cells ◽  
Caveolin 1 ◽  
Contractile Phenotype ◽  
Phenotype Expression

Monocyte-derived fibrocytes induce an inflammatory phenotype in airway smooth muscle cells

2014 ◽  
Vol 44 (11) ◽  
pp. 1347-1360 ◽  
Author(s):  
T.-Y. Lin ◽  
N. Venkatesan ◽  
M. Nishioka ◽  
S. Kyoh ◽  
L. Al-Alwan ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Airway Smooth Muscle ◽  
Muscle Cells ◽  
Airway Smooth Muscle Cells ◽  
Inflammatory Phenotype

scholarly journals Akt activation induces hypertrophy without contractile phenotypic maturation in airway smooth muscle

2011 ◽  
Vol 300 (5) ◽  
pp. L701-L709 ◽  
Author(s):  
Lan Ma ◽  
Melanie Brown ◽  
Paul Kogut ◽  
Karina Serban ◽  
Xiaojing Li ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Airway Smooth Muscle ◽  
Molecular Mechanisms ◽  
Glycogen Synthase ◽  
Progressive Increase ◽  
Akt Activation ◽  
Downstream Target ◽  
Lentiviral Infection ◽  
Gsk 3Β ◽  
Constitutively Active

Airway smooth muscle (ASM) hypertrophy is a cardinal feature of severe asthma, but the underlying molecular mechanisms remain uncertain. Forced protein kinase B/Akt 1 activation is known to induce myocyte hypertrophy in other muscle types, and, since a number of mediators present in asthmatic airways can activate Akt signaling, we hypothesized that Akt activation could contribute to ASM hypertrophy in asthma. To test this hypothesis, we evaluated whether Akt activation occurs naturally within airway myocytes in situ, whether Akt1 activation is sufficient to cause hypertrophy of normal airway myocytes, and whether such hypertrophy is accompanied by excessive accumulation of contractile apparatus proteins (contractile phenotype maturation). Immunostains of human airway sections revealed concordant activation of Akt (reflected in Ser473 phosphorylation) and of its downstream effector p70S6Kinase (reflected in Thr389 phosphorylation) within airway muscle bundles, but there was no phosphorylation of the alternative Akt downstream target glycogen synthase kinase (GSK) 3β. Artificial overexpression of constitutively active Akt1 (by plasmid transduction or lentiviral infection) caused a progressive increase in size and protein content of cultured canine tracheal myocytes and increased p70S6Kinase phosphorylation but not GSK3β phosphorylation; however, constitutively active Akt1 did not cause disproportionate overaccumulation of smooth muscle (sm) α-actin and SM22. Furthermore, mRNAs encoding sm-α-actin and SM22 were reduced. These results indicate that forced Akt1 signaling causes hypertrophy of cultured airway myocytes without inducing further contractile phenotypic maturation, possibly because of opposing effects on contractile protein gene transcription and translation, and suggest that natural activation of Akt1 plays a similar role in asthmatic ASM.

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