Role of reactive oxygen species in apoptosis of intestinal endothelial cells induced by heat stress / 解放军医学杂志

ABSTRACT

Objective To observe the oxidative stress, integrity of lysosome and apoptosis of intestinal epithelial cells 6 (IEC-6) after heat stress, and explore the pathogenesis of intestinal damage caused by heat stress.Methods In the heat stress groups,the cells were incubated at 43℃ for 1 hour, then, further incubated at 37℃ and 5% CO2 for 0, 1, 3, 6 and 12 hours respectively; in the medicine intervention group, the cells were pretreated with the medicine 1h before heat stress; while in control group, the cells were incubated at 37℃ and 5% CO2. The amount of reactive oxygen species (ROS) was assayed with 2', 7'-dichlorofluorescin diacetate (DCFH-DA) and dihydroethidium (DHE) staining. The stability of lysosome membrane was checked by AO staining. Apoptosis was analyzed by flow cytometry using annexinⅤ-FITC/PI staining, CCK-8 assay was used to assess cellular viability.Results Compared with control group, cell viability decreased and apoptosis increased at 1 h after heat stress, which was the most obvious at 12h after rewarming (P<0.05). While ROS and pale cells increased immediately after heat stress and the increase become the most obvious (P<0.05). The cell viability in E-64 pretreatment group was significantly improved such as apoptosis reduction, compared with heat stress group (P<0.05).Conclusion Heat stress could induce robust increase of ROS, which mediates lysosome damage and results in cell apoptosis, thus suggesting that ROS-lysosome pathway may play an important role in intestinal injury in heat stress.