Changes and regulation of NF-κB activity and IκB-α as well as TNF-α expression of murine peritoneal macrophages following severe burns

Objective To explore some mechanisms of macrophage functional disorder at the level of nuclear transcription factors by observing the dynamic changes of NF κB activity and TNF α secretion as well as IκB α expression by murine peritoneal macrophages (PMΦs) at different time intervals and after using NF κB inhibitor PDTC. Methods Model of 15% TBSA fullthickness scalded mice was used as experimental animal and PMΦs were collected. The following parameters were measured with the method indicated in parathesis: TNF α in supernatant of cultured PMΦs(RIA), TNF α mRNA (RT PCR), NF κB activity (electrophoretic mobility shift assay, EMSA), IκB α expression (modified ELISA and Western blotting). Results NF κB activity and TNF α secretion were markedly activated and reached their peak 2 h after burn and 12 h after burn respectively. Expression of IκB α decreased firstly and then increased to high level. After using NF κB specific inhbitor PDTC, NF κB activity and TNF α mRNA expression decreased at the same time. Conclusions NF κB activity and TNF α secretion are markedly activated after severe scald. High IκB α expression exhibits a strong regulatory effect on NF κB activation of PMΦs. NF κB pathway participate in the regulation of TNF α expression of macrophage after severe scald.