Cyclosporin A disrupts bradykinin signaling through superoxide.
Cyclosporin A disrupts bradykinin signaling through superoxide.
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环孢菌素 A 通过超氧化物破坏缓激肽信号传导。
DOI：
10.1161/01.hyp.0000068201.48340.3b
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发表时间：
2003
期刊：
影响因子：
--
通讯作者：
Chang,Chung-Ho
中科院分区：
文献类型：
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作者：
Vetter,Michael;Chen,Zi-Jiang;Chang,Geen-Dong;Che,Danian;Liu,Shiguo;Chang,Chung-Ho
环孢素 A (CsA) 用于降低移植排斥率。然而，长期使用会对肾脏产生破坏性的毒性作用，导致高血压。在本研究中，我们研究了 CsA 治疗对缓激肽/可溶性鸟苷酸环化酶信号级联的影响以及 LLC-PK1 猪肾近曲小管细胞中超氧化物的参与。用1μmol/L CsA处理24小时使基础cGMP水平增加41%，而CsA抑制缓激肽刺激的cGMP产生26%。蛋白质印迹显示 eNOS 表达增加，但缓激肽/可溶性鸟苷酸环化酶 (sGC) 途径中的其他蛋白没有受到影响。利用光泽精依赖性化学发光，我们发现 CsA 处理显着增加了超氧化物的产生。 10 μmol/L 羟嘌呤醇或 30 μmol/L 酮康唑并未显着降低 O2− 的产生。然而，它被 NADPH 氧化酶抑制剂氯化二亚苯基碘鎓 (10 μmol/L) 以及 O2-清除剂超氧化物歧化酶 (SOD) (100 U) 抑制。用 50 μmol/L 槲皮素、10 mmol/LN-乙酰半胱氨酸、两种抗氧化剂以及 O2−清除剂 Tiron (10 mmol/L) 处理，并与 1 μmol/L CsA 一起处理 24 小时，cGMP 产生的激活与 O2− 的减少相结合，得到恢复。用 100 μmol/L 甲萘醌（一种活性氧发生器）和 10 nmol/L 缓激肽孵育，对 cGMP 水平的影响与 CsA 相似。研究发现 CsA 治疗可增加硝基酪氨酸水平。这些发现表明，CsA 可能通过与 NO 结合形成过氧亚硝酸盐 (ONOO−) 来激活 NADPH 氧化酶，释放 O2− 并破坏缓激肽/可溶性鸟苷酸环化酶途径。
Cyclosporin A (CsA) is used to reduce transplant rejection rates. Chronic use, however, has a destructive toxic effect on the kidney, resulting in hypertension. In this study, we investigated the effects of CsA treatment on the bradykinin/soluble guanylate cyclase signaling cascade and the involvement of superoxide in LLC-PK1 porcine kidney proximal tubule cells. Treatment with 1 μmol/L CsA for 24 hours increased basal cGMP levels by 41%, whereas CsA inhibited bradykinin-stimulated cGMP production by 26%. Western blotting showed increased expression of eNOS, but no other protein in the bradykinin/soluble guanylate cyclase (sGC) pathway was affected. Using lucigenin-dependent chemiluminescence, we found that CsA treatment significantly increased superoxide production. Production of O2−was not significantly reduced by 10 μmol/L oxypurinol or 30 μmol/L ketoconazole. However, it was inhibited by the NADPH oxidase inhibitor diphenyleneiodonium chloride (10 μmol/L) as well as the O2−scavenger superoxide dismutase (SOD) (100 U). On treatment with 50 μmol/L quercetin, 10 mmol/LN-acetyl-cysteine, both antioxidants, as well as the O2−scavenger Tiron (10 mmol/L), concomitant with 1 μmol/L CsA for 24 hours the activation of cGMP production, was restored in combination with a reduction in O2−. Incubation with 100 μmol/L menadione, a reactive oxygen generator, and 10 nmol/L bradykinin showed similar effects on the level of cGMP as with CsA. CsA treatment was found to increase nitrotyrosine levels. These findings suggest that CsA activates a NADPH oxidase that releases O2−and disrupts the bradykinin/soluble guanylate cyclase pathway, probably by binding with NO to form peroxynitrite (ONOO−).