Expression Of Nrf2 In Macrophage (RAW264.7) Induced By Serum Of Burn Septic Rat

Objective:To study the expression of Nrf2 in macrophage(RAW264.7) induced by serum of septic rat of different group infected with endotoxins and bacteria.The main goal of our study is to research how Nrf2 is expressed in macrophage injured by some bacteria and endotoxins.Method:In this study,experiments were divided into two different categories;(1)Animal model and(2)Cell model.For the animal model, WISTAR rats were chosen as experimental animals.The rats were divided into the following 5 groups;1.Normal control group,2.LPS group,3.Pure Burn group,4.Pseudomonas group,and 5.Staphylococcus group.All four groups were made 40%deep second degree burn by keeping them in 90℃boiled water for 18 seconds except for the normal control group.Lethal dose of staphylococcus aureus 0.8ml(concentration becomes8×10⁹cuf/ml),Pseudomonas aeroginosa 0.5ml(contains1×10⁸cu f/ml bacteria)and LPS(6mgkg^-1)were injected into burnt mouse peritoneum according to the above groups.Blood collected from all the 5 groups by cardiac puncture at 8 hours were centrifuged to collect serum. Macrophage(RAW264.7)was used as a target cell and was interfered with above serum.RT-PCR and WESTERN BLOT were analyzed separately in order to study the expression of Nrf2 in that target cellsResult:There is prominent expression of Nrf2 in both RT-PCR and WESTERN BLOT experiments in all 5 groups.In RT-PCR,Nrf2 mRNA expression level is the highest in the Pure Burn group(81.19±3.83247), which is followed by the LPS group(71.8825±2.24292),Pseudomonas group(65.70752±2.97473),Staphylococcus group(60.525±3.5116)and the Normal control group(40.985±3.09207)respectively.In the WESTERN BLOT experiment,Nrf2 protein expression is the highest in the LPS group(97.733±3.274),which is followed by the pure burn group (89.8±2.9),pseudomonas group(80.066±2.059),staphylococcus group (73.333±3.082)and the normal control group(68.333±3.521) respectively.Conclusion:The expression of Nrf2 shows that the endogenous antioxidative system is present inside the macrophage RAW264.7 cell interfered with bacteria and LPS and protects against oxidative stress injury through endogenous antioxidant system.And can be a therapeutic goal for severe burn patient complicating MODS,septic shock etc.