ADAM-17 is activated by the mitogenic protein kinase ERK in a model of kidney fibrosis.
ADAM-17 is activated by the mitogenic protein kinase ERK in a model of kidney fibrosis.
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DOI：
10.1097/maj.0b013e3181cb4487
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发表时间：
2010-02
期刊：
影响因子：
--
通讯作者：
Gööz M
中科院分区：
文献类型：
--
作者：
Bell HL;Gööz M
慢性肾脏疾病影响九分之一的美国人，并导致肾衰竭和死亡。最近的科学证据表明，在疾病的发展过程中，去整合素和金属酶ADAM-17的活化增加，并且提出ADAM-17的苏氨酸磷酸化可能是酶活性的重要调节剂。本研究的目的是研究促纤维化5-羟色胺（5-HT）是否诱导ADAM-17的磷酸化，以及ADAM-17的磷酸化是否增加其酶活性。我们使用肾系膜细胞作为我们的模型系统，发现5-HT处理（1 μM，10分钟）诱导ADAM-17磷酸化显著增加3倍。细胞外信号调节激酶（ERK）激活抑制剂PD 98059（1 μM）可完全抑制ADAM-17的磷酸化。在免疫共沉淀分析中，我们观察到5-HT刺激10分钟后激活的ERK与ADAM-17的结合增加（2.7倍）。在使用荧光ADAM-17肽底物MCA-PLAQAV（Dpa）的ADAM-17活性测定中，我们发现5-HT处理诱导了2.3倍的ADAM-17活化，并且用1 μM PD 98059预处理显著减弱了5-HT诱导的ADAM-17活性（至对照的1.5倍）。我们的结论是，在促纤维化刺激ERK磷酸化ADAM-17苏氨酸在肾细胞和磷酸化的ADAM-17诱导伴随的酶活性增加。我们的数据表明，抑制ADAM-17磷酸化可能对减缓肾纤维化具有潜在的治疗意义。
Chronic kidney disease affects 1 out of 9 Americans and leads to kidney failure and death. Recent scientific evidence showed increased activation of the disintegrin and metalloenzyme ADAM-17 during development of the disease and it was suggested that threonine phosphorylation of ADAM-17 may be an important regulator of the enzyme activity. The goal of our study was to investigate whether profibrotic serotonin (5-HT) induces phosphorylation of ADAM-17 and whether phosphorylation of ADAM-17 increases its enzymatic activity. We used kidney mesangial cells as our model system and found that 5-HT treatment (1 μM for 10 min) induced a significant 3-fold increase in ADAM-17 phosphorylation. PD98059 (1 μM) an inhibitor of extracellular signal regulated kinase (ERK) activation completely inhibited ADAM-17 phosphorylation. In co-immunoprecipitation analysis we observed increased (2.7-fold) binding of activated ERK to ADAM-17 after 10 min of 5-HT stimulation. In ADAM-17 activity assay using a fluorogenic ADAM-17 peptide substrate MCA-PLAQAV(Dpa) we found that 5-HT treatment induced a 2.3-fold activation of ADAM-17 and that pre-treatment with 1 μM of PD98059 significantly attenuated 5-HT-induced ADAM-17 activity (to 1.5-fold over control). We conclude that during profibrotic stimulus ERK phosphorylates ADAM-17 on threonines in kidney cells and that phosphorylation of ADAM-17 induces concomitant increase in the enzyme activity. Our data suggest that inhibiting ADAM-17 phosphorylation can have potential therapeutic significance to slow down kidney fibrosis.