Tumor necrosis factor-α mediates pancreatitis responses in acinar cells via protein kinase C and proline-rich tyrosine kinase 2
Tumor necrosis factor-α mediates pancreatitis responses in acinar cells via protein kinase C and proline-rich tyrosine kinase 2
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DOI：
10.1053/j.gastro.2005.05.005
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发表时间：
2005-08-01
期刊：
影响因子：
29.4
通讯作者：
Pandol, SJ
中科院分区：
文献类型：
--
作者：
Satoh, A;Gukovskaya, AS;Pandol, SJ
背景和目标：虽然肿瘤坏死因子α是急性胰腺炎炎症反应的重要介质，但其在疾病其他病理特征中的作用仍不清楚。我们研究了肿瘤坏死因子α在胰腺腺泡细胞的细胞骨架反应和潜在的信号机制中的作用。研究方法：在离体大鼠胰腺腺泡和AR 42 J细胞中，我们用罗丹明鬼笔环肽检测了肿瘤坏死因子对肌动蛋白细胞骨架的影响。使用药理学和分子方法，我们评估了蛋白激酶C，Src激酶和富含脯氨酸的酪氨酸激酶2在这个过程中的参与。我们还研究了这些信号通路参与肿瘤坏死因子-α诱导的核因子-κ B活化和凋亡。结果：肿瘤坏死因子-α可增加腺泡细胞中富含脯氨酸的酪氨酸激酶2的酪氨酸磷酸化。广谱蛋白激酶C抑制剂和Src激酶抑制剂均抑制肿瘤坏死因子-α诱导的富含脯氨酸的酪氨酸激酶2磷酸化，但在不同的酪氨酸残基。使用蛋白激酶C亚型特异性抑制剂和反义方法，我们发现蛋白激酶C δ和β介导富含脯氨酸的酪氨酸激酶2酪氨酸磷酸化。肿瘤坏死因子-α通过依赖于蛋白激酶C、Src激酶和富含脯氨酸的酪氨酸激酶2的机制引起肌动蛋白细胞骨架的解体。抑制蛋白激酶C，但不是Src激酶，减少肿瘤坏死因子-α诱导的细胞凋亡。此外，通过反义转染，我们发现蛋白激酶C δ和酪氨酸激酶2介导肿瘤坏死因子α诱导的核因子-κ B活化，而非富含脯氨酸的酪氨酸激酶2。结论：肿瘤坏死因子-α激活富含脯氨酸的酪氨酸激酶2引起细胞骨架紊乱，激活核因子-κ B引起炎症反应，并通过蛋白激酶C介导的不同机制触发细胞死亡信号。这些结果为胰腺腺泡细胞中将肿瘤坏死因子α与急性胰腺炎的关键过程联系起来的机制提供了见解。
Background & Aims: Although tumor necrosis factor alpha is implicated as an important mediator of the inflammatory response in acute pancreatitis, its role in other pathologic features of the disease remains unknown. We investigated the role for tumor necrosis factor alpha in cytoskeletal responses and the underlying signaling mechanisms in pancreatic acinar cells. Methods: In isolated rat pancreatic acini and AR42J cells, we determined the effect of tumor necrosis factor (x on the actin cytoskeleton by rhodamine-phalloidin. Using pharmacological and molecular approaches, we assessed the involvement of protein kinase C, Src kinases, and proline-rich tyrosine kinase 2 in the process. We also studied the involvement of these signaling pathways in tumor necrosis factor-alpha-induced nuclear factor-kappa B activation and apoptosis. Results: Tumor necrosis factor-alpha increased the tyrosine phosphorylation of proline-rich tyrosine kinase 2 in acinar cells. The broad-spectrum protein kinase C inhibitor and the Src kinase inhibitor both inhibited tumor necrosis factor-alpha-induced proline-rich tyrosine kinase 2 phosphorylation, but at different tyrosine residues. Using protein kinase C isoform-specific inhibitors and the antisense approach, we showed that protein kinase C delta and epsilon mediate proline-rich tyrosine kinase 2 tyrosine phosphorylation. Tumor necrosis factor-alpha caused disorganization of the actin cytoskeleton by a mechanism dependent on protein kinase C, Src kinases, and proline-rich tyrosine kinase 2. Inhibition of protein kinase C, but not Src kinases, decreased tumor necrosis factor-alpha-induced apoptosis. Furthermore, with antisense transfections, we showed that protein kinase C delta and epsilon, but not proline-rich tyrosine kinase 2, mediate tumor necrosis factor alpha-induced nuclear factor-kappa B activation. Conclusions: Tumor necrosis factor-alpha activates proline-rich tyrosine kinase 2 to cause cytoskeletal disorganization and nuclear factor-kappa B to cause inflammatory response, and it triggers cell death signaling through divergent mechanisms mediated by protein kinase C. The results provide insights into the mechanisms in pancreatic acinar cells that link tumor necrosis factor alpha to critical processes in acute pancreatitis.