Department of Molecular Science and Technology, Ajou University, Suwon 443-749, Republic of Korea.
Department of Molecular Science and Technology, Ajou University, Suwon 443-749, Republic of Korea.
Biochem Biophys Res Commun. 2014 May 30;448(2):182-8. doi: 10.1016/j.bbrc.2014.04.083. Epub 2014 Apr 24.
Calcineurin inhibitors such as cyclosporin A (CsA) are widely used to treat organ transplantation-associated complications. However, CsA use is limited due to renal dysfunction. This study attempts to characterize the mechanism of CsA-induced nephrotoxicity using a human embryonic kidney cell line (HK-2). We performed microarray-based whole-genome expression analysis in HK-2 cells. CsA treatment induced the expression of endoplasmic reticulum (ER) stress-related and apoptosis-inducing genes at 6 and 24h, respectively, indicating that ER-stress predisposed the cells to apoptosis. G1 phase cell-cycle arrest was also observed via ER stress in CsA-treated cells. Furthermore, we found an inverse relationship between activating transcription factor 3 (ATF3), a stress-inducible protein, and C/EBP homologous protein (CHOP), an apoptosis-inducing protein. Moreover, when ATF3 knockdown cells were exposed to CsA, a prompt induction of CHOP was observed, which stimulated ROS production and induced cell death-related genes as compared to wild type. Taken together, our data demonstrate that ATF3 plays a pivotal role in the attenuation of CsA-induced nephrotoxicity by downregulating CHOP and ROS production mediated by ER stress.
钙调神经磷酸酶抑制剂如环孢素 A（CsA）被广泛用于治疗器官移植相关并发症。然而，由于肾功能障碍，CsA 的使用受到限制。本研究试图使用人胚肾细胞系（HK-2）来描述 CsA 诱导的肾毒性的机制。我们对 HK-2 细胞进行了基于微阵列的全基因组表达分析。CsA 处理分别在 6 小时和 24 小时诱导内质网（ER）应激相关和凋亡诱导基因的表达，表明 ER 应激使细胞易于凋亡。通过 ER 应激，在 CsA 处理的细胞中也观察到 G1 期细胞周期停滞。此外，我们发现应激诱导蛋白激活转录因子 3（ATF3）与凋亡诱导蛋白 C/EBP 同源蛋白（CHOP）之间存在反比关系。此外，当 ATF3 敲低细胞暴露于 CsA 时，与野生型相比，迅速诱导 CHOP，刺激 ROS 产生并诱导与细胞死亡相关的基因。总之，我们的数据表明，ATF3 通过下调 ER 应激介导的 CHOP 和 ROS 产生在减轻 CsA 诱导的肾毒性中起关键作用。
