Expression of Nrf2 in macrophage (RAW264.7) induced by serum of burn septic rat

Expression of Nrf2 in macrophage RAW264.7 induced by serum of septic rat infected with endotoxin and bacteria. Experiments were divided into animal model and cell model. For the animal model, the rats (n=45) were divided into normal control group, LPS group, Pure Burn group, Pseudomonas group, and Staphylococcus group. Rats of all groups were made 40 %total body surface area (TBSA) full thickness scald burn except normal control group. Lethal dose of Staphylococcus aureus, Pseudomonas aeruginosa and LPS were injected into burnt rat peritoneum according to the group respectively. Rats of all groups were killed by cardiac puncture method at 8 hours following burn and bloods collected were centrifuged to collect serum. Macrophage RAW264.7 cells were interfered with the serum separately. RT-PCR and Western blot were performed to study the expression of Nrf2. Nrf2 was prominently expressed in both experiments in all groups compared to normal control. In RT-PCR, Nrf2 mRNA expression level was the highest in the Pure Burn group (p<0.01) which was followed by the LPS group (p<0.01), Pseudomonas group (p<0.01) and Staphylococcus group (p<0.01) respectively. In the Western blot, Nrf2 protein expression was the highest in the LPS group (p<0.01) which was followed by the pure burn group (p<0.01), Pseudomonas group and staphylococcus group (p<0.05) respectively. The expression of Nrf2 indicates that different degree of endogenous anti oxidative system, host inflammatory response and its defense mechanism is active against oxidative stress inside the macrophage RAW264.7 interfered by different pathogens.