Role of transient receptor potential C3 in TNF-α-enhanced calcium influx in human airway myocytes
Role of transient receptor potential C3 in TNF-α-enhanced calcium influx in human airway myocytes
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DOI：
10.1165/rcmb.2006-0003oc
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发表时间：
2006-08-01
影响因子：
6.4
通讯作者：
Wylam, Mark E.
中科院分区：
文献类型：
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作者：
White, Thomas A.;Xue, Ailing;Wylam, Mark E.
先前的研究表明，促炎细胞因子肿瘤坏死因子 -α通过改变气道平滑肌（ASM）对激动剂刺激的钙离子（Ca²⁺）反应，导致气道高反应性。本研究检测了肿瘤坏死因子 -α对培养的人ASM细胞（HASMCs）中Ca²⁺内流途径的影响。瞬时受体电位（TRP）基因家族编码的蛋白质作为受体操纵性和储存操纵性Ca²⁺内流（SOCE）发生的通道发挥作用。在本研究中，通过逆转录聚合酶链反应（RT - PCR）和蛋白质印迹分析证实了培养的HASMCs中存在TRPC1、TRPC3、TRPC4、TRPC5和TRPC6的信使核糖核酸（mRNA）及蛋白质表达。肿瘤坏死因子 -α处理显著增加了HASMCs中TRPC3的mRNA和蛋白质水平以及SOCE。肿瘤坏死因子 -α处理还增加了乙酰胆碱和缓激肽引起的HASMCs内的峰值和平台期细胞内Ca²⁺浓度反应。使用小干扰RNA转染降低TRPC3表达后，肿瘤坏死因子 -α处理对SOCE和激动剂诱导的细胞内Ca²⁺浓度反应的影响减弱。因此，在炎症性气道疾病中，肿瘤坏死因子 -α处理可能由于Ca²⁺内流途径改变而导致肌细胞激活增加。这些结果表明，TRPC3可能是哮喘和慢性阻塞性肺疾病等炎症性气道疾病的一个重要治疗靶点。
Previous studies have suggested that the proinflammatory cytokine, TNF-alpha, contributes to airway hyperresponsivness by altering airway smooth muscle (ASM) Ca2+ responses to agonist stimulation. The present study examined the effects of TNF-alpha on Ca2+ influx pathways in cultured human ASM cells (HASMCs). Proteins encoded by the transient receptor potential (TRIP) gene family function as channels through which receptor-operated and store-operated Ca2+ entry (SOCE) occur. In the present study, the presence of TRPC1, TRPC3, TRPC4, TRPC5, and TRPC6 mRNA and protein expression was confirmed in cultured HASMCs using RT-PCR and Western blot analysis. TNIF-alpha treatment significantly increased TRPC3 mRNA and protein levels in HASMCs as well as SOCE. TNF-alpha treatment also increased both the peak and plateau intracellular Ca2+ concentration responses in HASMCs elicited by acetylcholine and bradykinin. The effects of TNF-alpha treatment on SOCE and agonist-induced intracellular Ca2+ concentration responses were attenuated using small interfering RNA transfection, which knocked down TRPC3 expression. Thus, in inflammatory airway diseases, TNF-alpha treatment may result in increased myocyte activation due to altered Ca2+ influx pathways. These results suggest that TRPC3 may be an important therapeutic target in inflammatory airway diseases such as asthma and chronic obstructive pulmonary disease.