The Protective Effect Of Heat Shock Pretreatment On The Hydrogen Peroxide Induced Cells Injury

[Objective]: The purpose of the research is to study the radioprotection character of heatshock proteins, through stimulating hydrogen peroxide as ionizing radiation. Theevaluating indicators includes two aspects: the strength of cell viability and the reductionof cell gene mutation. Because heat shock pretreatment is the best simple method to induceover expression of heat shock proteins, the optimal condition of heat shock pretreatmentof V79 and NIH3T3 was studied firstly. Then the protective effect of Heat shockpretreatment on the hydrogen peroxide induced cell viability damage and gene mutationboth were studied.[Methods]: Including three aspects:1.orthogonal experiment, that survival rate was measured by MTT, was adopted tostudy the optimal condition of heat shock pretreatment of V79 and NIH3T3.2.Cultured V79 cells were divided into three groups: heat shock pretreatment group,oxidation injury group and heat shock protection group, and control group was added intoall the three groups. The cell clone and dyeing method were adopted to measure cellviability.3.Cultured V79 cells were divided into three groups: heat shock pretreatment group,oxidation injury group and heat shock protection group, and control group was added intoall the three groups. Cell Clone was used to identify the cells of HPRT gene mutation andform cells clone, and Giemsa dyeing was applied to take count of the clones and computegene mutation rate of the groups.[Results]: 1. The heat shock pretreatment of 1 hours at 42℃and subsequently cultured in37℃for 4-8 hours may be the better Protective condition for V79 cells. The heat shockpretreatment of 0.5-2 hours at 42℃and subsequently cultured in 37℃for 2-8 hours may be the better Protective condition for NIH3T3 cells.2.To V79, the survival rate of heat shock protection group increased 20%, toNIH3T3, the survival rate of heat shock protection group increased 40%.3.Low cells density, there was no protective effect on the hydrogen peroxide inducedcell viability damage significantly (both clone ability and dyeing ability), P＞0.05.4.High cells density, heat shock pretreatment above 42℃would induce cell viabilitydamage significantly, P＜0.05.But below 42℃(including 42℃), there was no significantdamage, P＞0.05. There was protective effect on the hydrogen peroxide induced cellviability damage very significantly (both clone ability and dyeing ability), P＜0.01.5. After heat shock pretreatment of different temperature, the gene mutation rate ofcultured V79 cells did not increase significantly below 42℃(p＞0.05), but significantlyabove 42℃(p＜0.01).Heat shock pretreatment, had protection effect(compared with thehydrogen peroxide injury group)(p＜0.01).[Conclusion]1. Below 42℃(including 42℃),there was protective effect on the hydrogen peroxideinduced cell viability damage very significantly,both clone ability and dyeing ability, but42℃was optimal.2. Below 42℃(including 42℃),there was protective effect on the hydrogen peroxideinduced cell gene mutation very significantly, but 42℃was optimal.Above all, there was protective effect of heat shock pretreatment on the hydrogenperoxide induced cells injury, heat shock pretreatment had the radioprotection character, sodid heat shock proteins.