ANG II induces c-Jun NH2-terminal kinase activation and proliferation of human mesangial cells via redox-sensitive transactivation of the EGFR

作者：Ding Guixia; Zhang Aihua; Huang Songming; Pan Xiaoqin; Zhen Guo; Chen Ronghua; Yang Tianxin^*

来源：American Journal of Physiology - Renal Fluid and Electrolyte Physiology, 2007, 293(6): F1889-F1897.

DOI：10.1152/ajprenal.00112.2007

• glomerular disease
• reactive oxygen species
• cell growth

We previously showed that ANG II induces mesangial cell (MC) proliferation via the JNK-activator protein-1 pathway. The present study attempted to determine the upstream mediators of JNK activation, with emphasis on reactive oxygen species (ROS) and the epidermal growth factor (EGF) receptor (EGFR). In cultured human MCs (HMCs), as early as 3 min, ANG II time dependently increased intracellular ROS production, which was sensitive to 10 mu M diphenyleneiodonium sulfate and 500 mu M apocynin, two structurally distinct NADPH oxidase inhibitors. In contrast, inhibitors of other oxidant-producing enzymes, including the mitochondrial complex I inhibitor rotenone, the xanthine oxidase inhibitor allopurinol, the cyclooxygenase inhibitor indomethacin, the lipoxygenase inhibitor nordihydroguiaretic acid, the cytochrome P-450 oxygenase inhibitor ketoconazole, and the nitric oxide synthase inhibitor N-G-nitro-L-arginine methyl ester, were without effect. ANG II-induced ROS generation was inhibited by the angiotensin type 1 receptor antagonist losartan (10 mu M) but not the angiotensin type 2 receptor antagonist PD-123319 ( 10 mu M). ANG II induced translocation of p47(phox) and p67(phox) from the cytosol to the membrane. The antioxidants almost abolished the ANG II mitogenic response, as assessed by [H-3] thymidine incorporation and cell number, associated with a remarkable blockade of the activation of EGFR (90% inhibition) and JNK (83% inhibition). The EGFR inhibitor AG-1478 was able to mimic the effect of antioxidants, in that it inhibited the mitogenic response and the JNK activation following ANG II treatment. Together, these data suggest that the ROS-EGFRJNK pathway is involved in transducing the proliferative effect of ANG II in cultured HMCs.

• 出版日期2007-12
• 单位南京医科大学