Chang Seok-Woo, Lee Sang-Im, Bae Won-Jung, Min Kyung-San, Shin Eun-Sang, Oh Gi-Su, Pae Hyun-Ock, Kim Eun-Cheol
Department of Conservative Dentistry, The Institute of Oral Health Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
J Endod. 2009 Sep;35(9):1222-8. doi: 10.1016/j.joen.2009.06.005.
This study tested whether heat stress (42 degrees C for 30 minutes) induces reactive oxygen species (ROS), proinflammatory cytokines, Nrf2 activation, and Nrf2 target genes such as antioxidant enzymes in human dental pulp (HDP) cells.
ROS was evaluated by using flow cytometry. Proteins and messenger RNA levels for cytokines and antioxidant genes were determined by using Western blotting and reverse transcription-polymerase chain reaction (RT-PCR) analysis, respectively.
Heat stress induced the production of ROS and the increased expression of the interleukin (IL)-8 and IL-8 receptor genes. Exposure of cells to heat stress resulted in the nuclear translocation of Nrf2 and increased expression of Nrf2 target genes including heme oxygenase-1. Pretreatment with an exogenous antioxidant inhibited the heat-induced expression of IL-8 and Nrf2 target genes and Nrf2 translocation.
Collectively, these results show that heat-induced Nrf2 activation is the major regulatory pathway of cytoprotective gene expression against oxidative stress in HDP cells.
本研究旨在测试热应激（42摄氏度，持续30分钟）是否会诱导人牙髓（HDP）细胞中产生活性氧（ROS）、促炎细胞因子、核因子E2相关因子2（Nrf2）激活以及Nrf2靶基因（如抗氧化酶）。
通过流式细胞术评估ROS。分别使用蛋白质印迹法和逆转录聚合酶链反应（RT-PCR）分析来测定细胞因子和抗氧化基因的蛋白质和信使核糖核酸水平。
热应激诱导了ROS的产生以及白细胞介素（IL）-8和IL-8受体基因表达的增加。细胞暴露于热应激导致Nrf2的核转位以及包括血红素加氧酶-1在内的Nrf2靶基因表达增加。用外源性抗氧化剂预处理可抑制热诱导的IL-8和Nrf2靶基因表达以及Nrf2转位。
总体而言，这些结果表明热诱导的Nrf2激活是HDP细胞中针对氧化应激的细胞保护基因表达的主要调节途径。
