Musch M W, Ciancio M J, Sarge K, Chang E B
Department of Medicine, University of Chicago, Illinois 60637.
Am J Physiol. 1996 Feb;270(2 Pt 1):C429-36. doi: 10.1152/ajpcell.1996.270.2.C429.
The potential importance of inducible heat shock proteins (HSPs) in conferring protection to intestinal epithelial cells was investigated using IEC-18 cells. To establish optimal HSP induction, [35S]methionine and [35S]cysteine incorporation was assessed. Two 35S-labeled proteins of 70 and 90 kDa were preferentially synthesized. Western and Northern blot analyses confirmed induction of HSP70. This induction provided significant protection to the cells treated with the oxidant monochloramine or lethal heat (49 degrees C). To better establish the protective role of HSP70, cells were stably transfected with human HSP70 under control of the lac operator. When these cells were subjected to injury, they were protected by isopropylthiogalactoside-stimulated HSP70 induction under nonstress conditions. Additionally, the rate of protein synthesis (assessed by [3H]leucine incorporation) was protected. These results demonstrate that HSPs are preferentially and rapidly induced in IEC-18 cells and that induction of inducible HSP70 is important in promoting protection against cellular injury.
利用IEC - 18细胞研究了诱导型热休克蛋白（HSPs）在赋予肠道上皮细胞保护作用方面的潜在重要性。为了建立最佳的HSP诱导，评估了[35S]甲硫氨酸和[35S]半胱氨酸的掺入情况。优先合成了两种分子量分别为70 kDa和90 kDa的35S标记蛋白。蛋白质印迹法和Northern印迹分析证实了HSP70的诱导。这种诱导为用氧化剂一氯胺处理或致死性热（49℃）处理的细胞提供了显著的保护。为了更好地确定HSP70的保护作用，在乳糖操纵子的控制下用人HSP70对细胞进行稳定转染。当这些细胞受到损伤时，在非应激条件下异丙基硫代半乳糖苷刺激的HSP70诱导对其起到了保护作用。此外，蛋白质合成速率（通过[3H]亮氨酸掺入评估）也得到了保护。这些结果表明，HSPs在IEC - 18细胞中优先且快速地被诱导，并且诱导型HSP70的诱导在促进细胞免受损伤的保护中起重要作用。
