Limits...
Wnt/β-catenin signaling modulates human airway sensitization induced by β2-adrenoceptor stimulation.

Faisy C, Grassin-Delyle S, Blouquit-Laye S, Brollo M, Naline E, Chapelier A, Devillier P - PLoS ONE (2014)

Bottom Line: Compared to paired controls, fenoterol-sensitization was abolished by inhibition/blockage of the Wnt/β-catenin signaling, especially the cell-surface LRP5/6 co-receptors or Fzd receptors (1 µM SFRP1 or 1 µM DKK1) and the nuclear recruitment of TCF/LEF transcriptions factors (0.3 µM FH535).Wnt proteins secretion did not seem to be involved in the fenoterol-induced sensitization since the mRNA expression of Wnt remained low after fenoterol exposure and the inactivator of Wnt secretion (1 µM IWP2) had no effect on the fenoterol-sensitization.Collectively, our pharmacological investigations indicate that fenoterol-sensitization is modulated by the inhibition/blockage of canonical Wnt/β-catenin pathway, suggesting a phenomenon of biased agonism in connection with the β2-adrenoceptor stimulation.

View Article: PubMed Central - PubMed

Affiliation: Unité Propre de Recherche de l'Enseignement Supérieur, Equipe d'Accueil 220, Université Versailles Saint-Quentin, Hôpital Foch, Suresnes, France; Medical Intensive Care Unit, Hôpital Européen Georges Pompidou, Assistance Publique-Hôpitaux de Paris, Paris, France.

ABSTRACT

Background: Regular use of β2-agonists may enhance non-specific airway responsiveness. The wingless/integrated (Wnt) signaling pathways are responsible for several cellular processes, including airway inflammation and remodeling while cAMP-PKA cascade can activate the Wnt signaling. We aimed to investigate whether the Wnt signaling pathways are involved in the bronchial hyperresponsiveness induced by prolonged exposure to β2-adrenoceptor agonists in human isolated airways.

Methods: Bronchi were surgically removed from 44 thoracic surgery patients. After preparation, bronchial rings and primary cultures of bronchial epithelial cells were incubated with fenoterol (0.1 µM, 15 hours, 37 °C), a β2-agonist with high intrinsic efficacy. The effects of inhibitors/blockers of Wnt signaling on the fenoterol-induced airway sensitization were examined and the impact of fenoterol exposure on the mRNA expression of genes interacting with Wnt signaling or cAMP-PKA cascade was assessed in complete bronchi and in cultured epithelial cells.

Results: Compared to paired controls, fenoterol-sensitization was abolished by inhibition/blockage of the Wnt/β-catenin signaling, especially the cell-surface LRP5/6 co-receptors or Fzd receptors (1 µM SFRP1 or 1 µM DKK1) and the nuclear recruitment of TCF/LEF transcriptions factors (0.3 µM FH535). Wnt proteins secretion did not seem to be involved in the fenoterol-induced sensitization since the mRNA expression of Wnt remained low after fenoterol exposure and the inactivator of Wnt secretion (1 µM IWP2) had no effect on the fenoterol-sensitization. Fenoterol exposure did not change the mRNA expression of genes regulating Wnt signaling or cAMP-PKA cascade.

Conclusions: Collectively, our pharmacological investigations indicate that fenoterol-sensitization is modulated by the inhibition/blockage of canonical Wnt/β-catenin pathway, suggesting a phenomenon of biased agonism in connection with the β2-adrenoceptor stimulation. Future experiments based on the results of the present study will be needed to determine the impact of prolonged fenoterol exposure on the extra- and intracellular Wnt signaling pathways at the protein expression level.

Show MeSH

Related in: MedlinePlus

Concentration–response curves for endothelin-1 (ET-1)–induced contraction in human bronchi after 15 hours of incubation with 0.1 µM fenoterol or Krebs–Henseleit solution for the paired control in presence or in absence of: (A) Wortmaninn (1 µM); (B) Y27632 (1 µM); (C) Pioglitazone (1 µM); (D) FH535 (0.3 µM).Open circles, control; Filled circles, 0.1 µM fenoterol; Open square, control + pretreatment; Filled square, fenoterol + pretreatment. Values are means ± SEM. For comparisons, see Tables 1 and 2.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4216012&req=5

pone-0111350-g006: Concentration–response curves for endothelin-1 (ET-1)–induced contraction in human bronchi after 15 hours of incubation with 0.1 µM fenoterol or Krebs–Henseleit solution for the paired control in presence or in absence of: (A) Wortmaninn (1 µM); (B) Y27632 (1 µM); (C) Pioglitazone (1 µM); (D) FH535 (0.3 µM).Open circles, control; Filled circles, 0.1 µM fenoterol; Open square, control + pretreatment; Filled square, fenoterol + pretreatment. Values are means ± SEM. For comparisons, see Tables 1 and 2.

Mentions: Values were determined in paired human bronchi after incubation with 0.1 µM fenoterol or oxygenated Krebs–Henseleit solution (control) for 15 hours at 37°C with or without pretreatment co-incubated with fenoterol (Fig. 5–6). Emax (g) represented the maximal contraction induced by 0.1 µM ET-1. ΔEmax represented the difference between Emax obtained with the fenoterol-treated bronchi and Emax obtained with their paired controls. The observed effect of pretreatment co-incubated with fenoterol is small (/d/≥.20), medium (/d/≥.50), or large (/d/≥.80) according to the Cohen's conventions [36]. The 95% CI for d consists of the uncertainty around the real effect of pretreatment. †Except for wortmaninn which was added in organ bath before concentration-response curve for ET-1. *P<.05, **P<.01, ***P<.001 with vs without pretreatment.


Wnt/β-catenin signaling modulates human airway sensitization induced by β2-adrenoceptor stimulation.

Faisy C, Grassin-Delyle S, Blouquit-Laye S, Brollo M, Naline E, Chapelier A, Devillier P - PLoS ONE (2014)

Concentration–response curves for endothelin-1 (ET-1)–induced contraction in human bronchi after 15 hours of incubation with 0.1 µM fenoterol or Krebs–Henseleit solution for the paired control in presence or in absence of: (A) Wortmaninn (1 µM); (B) Y27632 (1 µM); (C) Pioglitazone (1 µM); (D) FH535 (0.3 µM).Open circles, control; Filled circles, 0.1 µM fenoterol; Open square, control + pretreatment; Filled square, fenoterol + pretreatment. Values are means ± SEM. For comparisons, see Tables 1 and 2.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4216012&req=5

pone-0111350-g006: Concentration–response curves for endothelin-1 (ET-1)–induced contraction in human bronchi after 15 hours of incubation with 0.1 µM fenoterol or Krebs–Henseleit solution for the paired control in presence or in absence of: (A) Wortmaninn (1 µM); (B) Y27632 (1 µM); (C) Pioglitazone (1 µM); (D) FH535 (0.3 µM).Open circles, control; Filled circles, 0.1 µM fenoterol; Open square, control + pretreatment; Filled square, fenoterol + pretreatment. Values are means ± SEM. For comparisons, see Tables 1 and 2.
Mentions: Values were determined in paired human bronchi after incubation with 0.1 µM fenoterol or oxygenated Krebs–Henseleit solution (control) for 15 hours at 37°C with or without pretreatment co-incubated with fenoterol (Fig. 5–6). Emax (g) represented the maximal contraction induced by 0.1 µM ET-1. ΔEmax represented the difference between Emax obtained with the fenoterol-treated bronchi and Emax obtained with their paired controls. The observed effect of pretreatment co-incubated with fenoterol is small (/d/≥.20), medium (/d/≥.50), or large (/d/≥.80) according to the Cohen's conventions [36]. The 95% CI for d consists of the uncertainty around the real effect of pretreatment. †Except for wortmaninn which was added in organ bath before concentration-response curve for ET-1. *P<.05, **P<.01, ***P<.001 with vs without pretreatment.

Bottom Line: Compared to paired controls, fenoterol-sensitization was abolished by inhibition/blockage of the Wnt/β-catenin signaling, especially the cell-surface LRP5/6 co-receptors or Fzd receptors (1 µM SFRP1 or 1 µM DKK1) and the nuclear recruitment of TCF/LEF transcriptions factors (0.3 µM FH535).Wnt proteins secretion did not seem to be involved in the fenoterol-induced sensitization since the mRNA expression of Wnt remained low after fenoterol exposure and the inactivator of Wnt secretion (1 µM IWP2) had no effect on the fenoterol-sensitization.Collectively, our pharmacological investigations indicate that fenoterol-sensitization is modulated by the inhibition/blockage of canonical Wnt/β-catenin pathway, suggesting a phenomenon of biased agonism in connection with the β2-adrenoceptor stimulation.

View Article: PubMed Central - PubMed

Affiliation: Unité Propre de Recherche de l'Enseignement Supérieur, Equipe d'Accueil 220, Université Versailles Saint-Quentin, Hôpital Foch, Suresnes, France; Medical Intensive Care Unit, Hôpital Européen Georges Pompidou, Assistance Publique-Hôpitaux de Paris, Paris, France.

ABSTRACT

Background: Regular use of β2-agonists may enhance non-specific airway responsiveness. The wingless/integrated (Wnt) signaling pathways are responsible for several cellular processes, including airway inflammation and remodeling while cAMP-PKA cascade can activate the Wnt signaling. We aimed to investigate whether the Wnt signaling pathways are involved in the bronchial hyperresponsiveness induced by prolonged exposure to β2-adrenoceptor agonists in human isolated airways.

Methods: Bronchi were surgically removed from 44 thoracic surgery patients. After preparation, bronchial rings and primary cultures of bronchial epithelial cells were incubated with fenoterol (0.1 µM, 15 hours, 37 °C), a β2-agonist with high intrinsic efficacy. The effects of inhibitors/blockers of Wnt signaling on the fenoterol-induced airway sensitization were examined and the impact of fenoterol exposure on the mRNA expression of genes interacting with Wnt signaling or cAMP-PKA cascade was assessed in complete bronchi and in cultured epithelial cells.

Results: Compared to paired controls, fenoterol-sensitization was abolished by inhibition/blockage of the Wnt/β-catenin signaling, especially the cell-surface LRP5/6 co-receptors or Fzd receptors (1 µM SFRP1 or 1 µM DKK1) and the nuclear recruitment of TCF/LEF transcriptions factors (0.3 µM FH535). Wnt proteins secretion did not seem to be involved in the fenoterol-induced sensitization since the mRNA expression of Wnt remained low after fenoterol exposure and the inactivator of Wnt secretion (1 µM IWP2) had no effect on the fenoterol-sensitization. Fenoterol exposure did not change the mRNA expression of genes regulating Wnt signaling or cAMP-PKA cascade.

Conclusions: Collectively, our pharmacological investigations indicate that fenoterol-sensitization is modulated by the inhibition/blockage of canonical Wnt/β-catenin pathway, suggesting a phenomenon of biased agonism in connection with the β2-adrenoceptor stimulation. Future experiments based on the results of the present study will be needed to determine the impact of prolonged fenoterol exposure on the extra- and intracellular Wnt signaling pathways at the protein expression level.

Show MeSH
Related in: MedlinePlus