Department of Internal Medicine 1, Shimane University Faculty of Medicine, Shimane, Japan.
J Diabetes Complications. 2013 Jan-Feb;27(1):11-5. doi: 10.1016/j.jdiacomp.2012.07.006. Epub 2012 Sep 1.
Tumor necrosis factor (TNF)-α and reactive oxygen species (ROS) are involved in the endothelial dysfunction and the progression of atherosclerosis. In the pathogenesis of diabetic micro- and macro-vascular complications, advanced glycation end products (AGEs) and their receptor signaling are thought to play pivotal roles. We have studied the interaction among AGEs, TNF-α and ROS production using human aortic endothelial cells (HAoEC), and elucidated the significance of transcription factor NF-κB in that interaction. Concentration of TNF-α as well as 8-hydroxy-2'-deoxyguanosine (8-OHdG), an indicator of ROS generation, in the culture medium was significantly elevated 24 h after treatment with glycolaldehyde-derived AGE3. Antioxidant TEMPOL almost completely inhibited AGE3-induced TNF-α secretion, whereas NF-κB inhibitor PDTC partly suppressed AGE3-induced 8-OHdG production. Since NF-κB, which induces TNF-α expression is activated by ROS and TNF-α itself, AGE3-induced ROS generation is partly through NF-κB activation and subsequent TNF-α production in these cells. Our findings suggest that sustained activation of NF-κB might be crucial for endothelial dysfunction in diabetes, and that inhibition of local NF-κB and/or TNF-α action could be one of therapeutic strategies for vascular complications.
肿瘤坏死因子 (TNF)-α 和活性氧 (ROS) 参与内皮功能障碍和动脉粥样硬化的进展。在糖尿病微血管和大血管并发症的发病机制中,认为晚期糖基化终产物 (AGEs) 及其受体信号转导发挥关键作用。我们使用人主动脉内皮细胞 (HAoEC) 研究了 AGEs、TNF-α 和 ROS 产生之间的相互作用,并阐明了转录因子 NF-κB 在这种相互作用中的意义。在甘醛衍生的 AGE3 处理 24 小时后,培养基中 TNF-α 的浓度以及 ROS 产生的指标 8-羟基-2'-脱氧鸟苷 (8-OHdG) 显著升高。抗氧化剂 TEMPOL 几乎完全抑制 AGE3 诱导的 TNF-α 分泌,而 NF-κB 抑制剂 PDTC 部分抑制 AGE3 诱导的 8-OHdG 产生。由于诱导 TNF-α 表达的 NF-κB 被 ROS 和 TNF-α 本身激活,因此 AGE3 诱导的 ROS 生成部分通过这些细胞中的 NF-κB 激活和随后的 TNF-α 产生。我们的发现表明,NF-κB 的持续激活可能对糖尿病中的内皮功能障碍至关重要,并且抑制局部 NF-κB 和/或 TNF-α 作用可能是血管并发症的治疗策略之一。