Abstract：
OBJECTIVE: Adhesion molecules play vital roles in the induction of airway hyperresponsiveness (AHR) or airway inflammation. The down-regulation of catenin alpha-like 1 (CTNNAL1) in the bronchial epithelial cells of asthma patients and mice models has been noted in our previous study. In this work, we further explore the underlying mechanism of CTNNAL1 in asthma.
METHODS: We constructed a house dust mite (HDM)-induced asthma animal model on control mice and applied CTNNAL1-siRNA transfection to create CTNNAL1-deficient mice.
RESULTS: We documented much more severe airway inflammation and increased leukocyte infiltration in the lungs of the CTNNAL1-deficient mice comparing to control mice, along with elevated expression of inflammatory cytokines. Dexamethasone (DEX) treatment led to less reduced inflammation in CTNNAL1-deficient mice compared with control mice. Immunoprecipitation confirmed the interaction between heat shock protein90 (hsp90) and CTNNAL1. The expression of hsp90 was upregulated after CTNNAL1 silencing. Meanwhile, the use of hsp90 inhibitor geldanamycin significantly decreased the expression of NR3C1, ICAM-1 and the ratio of p-p65/p65 in CTNNAL1-silenced 16HBE14o- cells. Both geldanamycin and DEX could function to suppress the expression of ICAM-1 and the phosphorylation level of p65. Nevertheless, the anti-inflammatory effect of DEX proved less potent than geldanamycin in the CTNNAL1-silenced group. The combined therapy of geldanamycin and DEX significantly decreased the inflammatory responses in CTNNAL1-deficient HBE cells than DEX monotherapy.
CONCLUSIONS: Our study corroborates that CTNNAL1 deficiency induced aggravated airway inflammation and rendered insensitivity to glucocorticoids via triggering hsp90 signaling pathway.
METHODS: We constructed a house dust mite (HDM)-induced asthma animal model on control mice and applied CTNNAL1-siRNA transfection to create CTNNAL1-deficient mice.
RESULTS: We documented much more severe airway inflammation and increased leukocyte infiltration in the lungs of the CTNNAL1-deficient mice comparing to control mice, along with elevated expression of inflammatory cytokines. Dexamethasone (DEX) treatment led to less reduced inflammation in CTNNAL1-deficient mice compared with control mice. Immunoprecipitation confirmed the interaction between heat shock protein90 (hsp90) and CTNNAL1. The expression of hsp90 was upregulated after CTNNAL1 silencing. Meanwhile, the use of hsp90 inhibitor geldanamycin significantly decreased the expression of NR3C1, ICAM-1 and the ratio of p-p65/p65 in CTNNAL1-silenced 16HBE14o- cells. Both geldanamycin and DEX could function to suppress the expression of ICAM-1 and the phosphorylation level of p65. Nevertheless, the anti-inflammatory effect of DEX proved less potent than geldanamycin in the CTNNAL1-silenced group. The combined therapy of geldanamycin and DEX significantly decreased the inflammatory responses in CTNNAL1-deficient HBE cells than DEX monotherapy.
CONCLUSIONS: Our study corroborates that CTNNAL1 deficiency induced aggravated airway inflammation and rendered insensitivity to glucocorticoids via triggering hsp90 signaling pathway.
摘要：
目的：粘附分子在诱导气道高反应性（AHR）或气道炎症中起重要作用。在我们之前的研究中已经注意到在哮喘患者和小鼠模型的支气管上皮细胞中连环蛋白α样1(CTNNAL1)的下调。在这项工作中,我们进一步探讨了CTNNAL1在哮喘中的作用机制。
方法：我们在对照小鼠上构建了屋尘螨（HDM）诱导的哮喘动物模型，并应用CTNNAL1-siRNA转染来创建CTNNAL1缺陷小鼠。
结果：我们记录了与对照小鼠相比，缺乏CTNNAL1的小鼠肺部更严重的气道炎症和白细胞浸润增加，伴随着炎性细胞因子的表达升高。与对照小鼠相比，地塞米松（DEX）治疗导致CTNNAL1缺陷小鼠炎症减少。免疫沉淀证实了热休克蛋白90（hsp90）和CTNNAL1之间的相互作用。CTNNAL1沉默后，hsp90的表达上调。同时,使用hsp90抑制剂格尔德霉素可显著降低CTNNAL1沉默的16HBE14o细胞中NR3C1,ICAM-1的表达和p-p65/p65的比值.格尔德霉素和DEX均可抑制ICAM-1的表达和p65的磷酸化水平。然而，在CTNNAL1沉默组中,DEX的抗炎作用不如格尔德霉素.与DEX单一疗法相比，格尔德霉素和DEX的联合疗法显着降低了CTNNAL1缺陷型HBE细胞的炎症反应。
结论：我们的研究证实，CTNNAL1缺乏通过触发hsp90信号通路导致气道炎症加重，并导致对糖皮质激素不敏感。
方法：我们在对照小鼠上构建了屋尘螨（HDM）诱导的哮喘动物模型，并应用CTNNAL1-siRNA转染来创建CTNNAL1缺陷小鼠。
结果：我们记录了与对照小鼠相比，缺乏CTNNAL1的小鼠肺部更严重的气道炎症和白细胞浸润增加，伴随着炎性细胞因子的表达升高。与对照小鼠相比，地塞米松（DEX）治疗导致CTNNAL1缺陷小鼠炎症减少。免疫沉淀证实了热休克蛋白90（hsp90）和CTNNAL1之间的相互作用。CTNNAL1沉默后，hsp90的表达上调。同时,使用hsp90抑制剂格尔德霉素可显著降低CTNNAL1沉默的16HBE14o细胞中NR3C1,ICAM-1的表达和p-p65/p65的比值.格尔德霉素和DEX均可抑制ICAM-1的表达和p65的磷酸化水平。然而，在CTNNAL1沉默组中,DEX的抗炎作用不如格尔德霉素.与DEX单一疗法相比，格尔德霉素和DEX的联合疗法显着降低了CTNNAL1缺陷型HBE细胞的炎症反应。
结论：我们的研究证实，CTNNAL1缺乏通过触发hsp90信号通路导致气道炎症加重，并导致对糖皮质激素不敏感。
