Role of ERK MAP kinases in responses of cultured human airway smooth muscle cells to IL-1β
Role of ERK MAP kinases in responses of cultured human airway smooth muscle cells to IL-1β
复制标题
DOI：
10.1152/ajplung.1999.277.5.l943
复制
发表时间：
1999-11-01
影响因子：
4.9
通讯作者：
Shore, SA
中科院分区：
文献类型：
--
作者：
Laporte, JD;Moore, PE;Shore, SA
我们以前曾报道，白细胞介素（IL）-1 β通过增加环氧合酶-2（考克斯-2）表达和前列腺素形成，导致培养的人气道平滑肌细胞β-肾上腺素能低反应性。本研究的目的是确定细胞外信号调节激酶（ERK）是否参与这些事件。单独用IL-1 β（20 mg/ml）处理后15分钟，磷酸化ERK（p42和p44）水平分别增加8.3倍和18倍。用丝裂原活化蛋白激酶激酶抑制剂PD-98059或U-126预处理细胞（IL-1 β处理前2小时）可降低ERK磷酸化。单独IL-1 β（20 ng/ml，22 h）可显著诱导考克斯-2的表达，并使基础PGE（2）释放增加28倍（P < 0.001）。当在IL-1 β治疗前给药时，PD-98059（100 μ M）和U-126（10 μ M）均降低考克斯-2表达。在对照细胞中，PD-98059和U-126对基础或花生四烯酸没有影响。（AA; 10 μ M）刺激PGE（2）释放，但两种抑制剂均引起缓激肽显著降低（BK; 1 μ M）刺激的PGE（2）释放，这与ERK在BK激活磷脂酶A（2）中的作用一致。在IL-1 β处理的细胞中，预先给予PD-98059可使基础PGE（2）释放和BK及AA刺激的PGE（2）释放分别降低81%、92%和40（P < 0.01），而在IL-1 β后20小时给予PD-98059仅导致基础和BK刺激的PGE（2）释放减少38%和43%，对AA刺激的PGE（2）释放无影响（P> 0.05）。IL-1 β可减弱异丙肾上腺素诱导的人气道平滑肌僵硬度降低（通过磁扭转细胞术测量），PD-98059或U-126以浓度依赖性方式消除了这种作用。这些结果与以下假设一致：ERK参与IL-1 β诱导PGE（2）合成和β-肾上腺素能低反应的信号转导途径的早期，ERK通过诱导考克斯-2和激活磷脂酶A（2）发挥作用。
We have previously reported that interleukin (IL)-1 beta causes beta-adrenergic hyporesponsiveness in cultured human airway smooth muscle cells by increasing cyclooxygenase-2 (COX-2) expression and prostanoid formation. The purpose of this study was to determine whether extracellular signal-regulated kinases (ERKs) are involved in these events. Levels of phosphorylated ERK (p42 and p44) increased 8.3- and 18-fold, respectively, 15 min after treatment with IL-1 beta (20 mg/ml) alone. Pretreating cells with the mitogen-activated protein kinase kinase inhibitor PD-98059 or U-126 (2 h before IL-1 beta treatment) decreased ERK phosphorylation. IL-1 beta (20 ng/ml for 22 h) alone caused a marked induction of COX-2 and increased basal PGE(2) release 28-fold (P < 0.001). PD-98059 (100 mu M) and U-126 (10 mu M) each decreased COX-2 expression when administered before IL-1 beta treatment. In control cells, PD-98059 and U-126 had no effect on basal or arachidonic acid (AA; 10 mu M)-stimulated PGE(2) release, but both inhibitors caused a significant decrease in bradykinin (BK; 1 mu M)-stimulated PGE(2) release, consistent with a role for ERK in the activation of phospholipase A(2) by BK. In IL-lp-treated cells, prior administration of PD-98059 caused 81, 92 and 40% decreases in basal and BK-and AA-stimulated PGE(2) release, respectively (P < 0.01), whereas administration of PD-98059 20 h after IL-1 beta resulted in only 38 and 43% decreases in basal and BK-stimulated PGE(2) release, respectively (P < 0.02) and had no effect on AA-stimulated PGE(2) release. IL-1 beta attenuated isoproterenol-induced decreases in human airway smooth muscle stiffness as measured by magnetic twisting cytometry, and PD-98059 or U-126 abolished this effect in a concentrationdependent manner. These results are consistent with the hypothesis that ERKs are involved early in the signal transduction pathway through which IL-1 beta induces PGE(2) synthesis and beta-adrenergic hyporesponsiveness and that ERKs act by inducing COX-2 and activating phospholipase A(2).