Nerve growth factor reduces amiloride-sensitive Na+ transport in human airway epithelial cells.
Nerve growth factor reduces amiloride-sensitive Na+ transport in human airway epithelial cells.
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DOI：
10.14814/phy2.12073
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发表时间：
2014-07-16
影响因子：
2.5
通讯作者：
Fedan JS
中科院分区：
文献类型：
--
作者：
Shimko MJ;Zaccone EJ;Thompson JA;Schwegler-Berry D;Kashon ML;Fedan JS
神经生长因子（NGF）在炎症性肺部疾病（包括病毒感染）患者中过度表达。气道表面液体（ASL）受上皮细胞离子转运调节，对于正常肺功能至关重要。没有关于 NGF 对气道上皮离子转运影响的信息。为了研究NGF是否会影响离子转运，将人原代空气界面培养的上皮细胞置于Ussing室中以获得跨上皮电压（-7.1±3.4mV）、短路电流（Isc，5.9±1.0μA）和跨上皮电阻（750Ω·cm2），并测量对离子转运抑制剂的反应。阿米洛利（顶端，3.5 × 10−5 mol/L）使 Isc 降低 55.3%。顶部应用 NGF (1 ng/mL) 在 5 分钟内使 Isc 降低 5.3%；基底外侧应用NGF没有效果。 NGF 存在时，阿米洛利的反应降低 (41.6%)。 K-252a（10 nmol/L，顶端）本身并不影响Na+转运，但它减弱了NGF诱导的Na+转运减少，表明trkA受体参与了NGF诱导的Na+转运减少。 PD-98059（30 μmol/L，顶端和基底外侧）本身并不影响 Na+ 转运，但减弱了 NGF 诱导的 Na+ 转运减少，表明 trkA 激活了 Erk 1/2 信号级联。 NGF 刺激 Erk 1/2 和 ENaC β 亚基的磷酸化。 K-252a 和 PD-98059 抑制这些反应。在顶端制霉菌素（50 μmol/L）存在下，NGF 对 Isc 没有影响。这些结果表明，NGF 通过与 ENaC 磷酸化相关的 trkA-Erk 1/2 激活信号通路抑制 Na+ 转运。神经生长因子（顶端，1 ng/mL）可减少人培养的支气管上皮细胞中阿米洛利敏感的 Na+ 转运。我们确定 Na+ 转运的减少是通过 NGF 介导的 trkA 受体激活和 Erk 1/2 信号级联反应导致 ENaC 磷酸化而发生的。
Nerve growth factor (NGF) is overexpressed in patients with inflammatory lung diseases, including virus infections. Airway surface liquid (ASL), which is regulated by epithelial cell ion transport, is essential for normal lung function. No information is available regarding the effect of NGF on ion transport of airway epithelium. To investigate whether NGF can affect ion transport, human primary air‐interface cultured epithelial cells were placed in Ussing chambers to obtain transepithelial voltage (−7.1 ± 3.4 mV), short‐circuit current (Isc, 5.9 ± 1.0 μA), and transepithelial resistance (750 Ω·cm2), and to measure responses to ion transport inhibitors. Amiloride (apical, 3.5 × 10−5 mol/L) decreased Isc by 55.3%. Apically applied NGF (1 ng/mL) reduced Isc by 5.3% in 5 min; basolaterally applied NGF had no effect. The response to amiloride was reduced (41.6%) in the presence of NGF. K‐252a (10 nmol/L, apical) did not itself affect Na+ transport, but it attenuated the NGF‐induced reduction in Na+ transport, indicating the participation of the trkA receptor in the NGF‐induced reduction in Na+ transport. PD‐98059 (30 μmol/L, apical and basolateral) did not itself affect Na+ transport, but attenuated the NGF‐induced reduction in Na+ transport, indicating that trkA activated the Erk 1/2 signaling cascade. NGF stimulated phosphorylation of Erk 1/2 and the β‐subunit of ENaC. K‐252a and PD‐98059 inhibited these responses. NGF had no effect on Isc in the presence of apical nystatin (50 μmol/L). These results indicate that NGF inhibits Na+ transport through a trkA‐Erk 1/2‐activated signaling pathway linked to ENaC phosphorylation. Nerve growth factor (apical, 1 ng/mL) reduced amiloride‐sensitive Na+ transport in human cultured bronchial epithelial cells. We determined that this reduction in Na+ transport occurred through NGF‐mediated activation of the trkA receptor and Erk 1/2 signaling cascade to cause phosphorylation of ENaC.