[Heat shock protein 70 induction by heat stress suppress interleukin-1beta and tumor necrosis factor-alpha levels in the brain tissue in rats with infectious brain edema].

OBJECTIVE

To investigate the changes of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) in the brain tissue of rats with infectious brain edema (IBE) and their relationship with heat shock protein 70 (HSP70) by heat stress response (HSR).

METHODS

Seventy-two SD rats were randomly divided into normal controls group (NS group), IBE group, and HSP group, each group was divided into three subgroups. The rats in subgroups were killed at 4 hours, 8 hours and 24 hours after the injections of IBE or normal saline respectively. HSP70 in brain tissues were determined by western blot analysis. The concentrations of IL-1beta and TNF-alpha in the brain homogenate of rats were determined by enzyme linked immunoadsorbent assay (ELISA).

RESULTS

The results showed that HSP70 in brain tissues were elevated after heat shock. IBE group and NS group at 4 hours, 8 hours, 24 hours were induced to base levels of HSP70. The concentrations of TNF-alpha were significantly elevated in IBE group than in NS group at the various time points (P<0.01 or P<0.05), especially at 8 hours. The concentrations of IL-1beta were significantly increased in IBE group compared with NS group at 4 hours, 8 hours. HSR reduced the IL-1beta and TNF-alpha concentrations in the brain tissue in compared with IBE group (P<0.05 or P<0.01).

CONCLUSION

IL-1beta and TNF-alpha are involved in infectious brain edema by IBE. HSP70 against infectious brain edema in rats may be associated with the reduction of IL-1beta and TNF-alpha in brain tissue.