Functional KCa3.1 channels regulate steroid insensitivity in bronchial smooth muscle cells.
Functional KCa3.1 channels regulate steroid insensitivity in bronchial smooth muscle cells.
复制标题
DOI：
10.4049/jimmunol.1300104
复制
发表时间：
2013-09-01
期刊：
影响因子：
--
通讯作者：
Amrani Y
中科院分区：
文献类型：
--
作者：
Chachi L;Shikotra A;Duffy SM;Tliba O;Brightling C;Bradding P;Amrani Y
确定导致重症哮喘患者出现相对糖皮质激素（GC）抵抗的因素，并寻找逆转这种抵抗的方法至关重要。在哮喘患者体内，有证据表明气道平滑肌（ASM）束中存在GC抵抗通路，在体外可通过将培养的ASM细胞暴露于肿瘤坏死因子α（TNFα）/干扰素γ（IFNγ）来模拟这一情况。这会通过蛋白磷酸酶 - 5（PP5）依赖的方式损害GC受体（GR）的磷酸化，从而导致GC不敏感。在此，我们利用GC不敏感的ASM模型，研究KCa3.1离子通道是否对GC抵抗通路的活性有调节作用。支气管内活检组织的免疫组化染色显示，无论疾病严重程度如何，在健康对照组和哮喘患者的ASM中，KCa3.1通道均定位于质膜和细胞核。蛋白质免疫印迹分析和免疫荧光染色证实了KCa3.1通道在ASM细胞中的核定位。我们采用了包括KCa3.1阻滞剂（TRAM - 34和ICA - 17043）或腺病毒递送的KCa3.1特异性短发夹RNA（shRNA）等互补抑制策略，来评估KCa3.1通道在调节由TNFα/IFNγ诱导的GC抵抗趋化因子方面的功能重要性。KCa3.1通道阻断导致氟替卡松抵抗的CX3CL1、CCL5和CCL11基因及蛋白表达显著降低。KCa3.1通道阻断还通过抑制细胞因子诱导的PP5表达，恢复了氟替卡松诱导的GRα在丝氨酸211位点的磷酸化及其反式激活特性。KCa3.1阻断的作用在健康对照组和哮喘患者的ASM细胞中均很明显。总之，KCa3.1通道参与调节ASM细胞中的GC抵抗炎症通路：阻断KCa3.1通道可能增强重症哮喘中皮质类固醇的活性。
Identifying the factors responsible for relative glucocorticosteroid (GC) resistance present in patients with severe asthma and finding tools to reverse it are of paramount importance. In asthma there is in vivo evidence of GC-resistant pathways in airway smooth muscle (ASM) bundles which can be modelled in vitro by exposing cultured ASM cells to TNFα/IFNγ. This drives GC insensitivity via protein phosphatase-5 (PP5)-dependent impairment of GC receptor (GR) phosphorylation. Here, we investigated whether KCa3.1 ion channels modulate the activity of GC-resistant pathways using our ASM model of GC insensitivity. Immunohistochemical staining of endobronchial biopsies revealed that KCa3.1 channels are localized to the plasma membrane and nucleus of ASM in both healthy controls and asthmatic patients, irrespective of disease severity. Western blot assays and immunofluorescence staining confirmed the nuclear localisation of KCa3.1 channels in ASM cells. The functional importance of KCa3.1 channels in the regulation of GC-resistant chemokines induced by TNFα/IFNγ was assessed using complementary inhibitory strategies including KCa3.1 blockers (TRAM-34 and ICA-17043) or KCa3.1-specific shRNA delivered by adenoviruses. KCa3.1 channel blockade led to a significant reduction of fluticasone-resistant CX3CL1, CCL5 and CCL11 gene and protein expression. KCa3.1 channel blockade also restored fluticasone-induced GRα phosphorylation at ser211 and transactivation properties via the suppression of cytokine-induced PP5 expression. The effect of KCa3.1 blockade was evident in ASM cells from both healthy controls and asthmatic subjects. In summary KCa3.1 channels contribute to the regulation of GC-resistant inflammatory pathways in ASM cells: blocking KCa3.1 channels may enhance corticosteroid activity in severe asthma.
登录
查看更多内容
DOI：
10.1165/ajrcmb.10.5.8179909
发表时间：
1994-05-01
影响因子：
6.4
作者：
BRADDING, P;ROBERTS, JA;HOLGATE, ST
通讯作者：
HOLGATE, ST
影响因子：
5.4
作者：
Duffy, S Mark;Cruse, Glenn;Brightling, Christopher E;Bradding, Peter
通讯作者：
Bradding, Peter
影响因子：
4.4
作者：
El-Shazly, A;Berger, P;Tunon-de-Lara, JM
通讯作者：
Tunon-de-Lara, JM
影响因子：
158.5
作者：
Cox, Gerard;Thomson, Neil C.;Olsen, M.
通讯作者：
Olsen, M.
DOI：
10.1016/j.jaci.2011.07.047
发表时间：
2011-12
期刊：
The Journal of allergy and clinical immunology
影响因子：
--
作者：
Cruse G;Singh SR;Duffy SM;Doe C;Saunders R;Brightling CE;Bradding P
通讯作者：
Bradding P