Objective:To explore the effect and the mechanism of TREM-1vshRNA in the form of sepsis in mice caused by live bacteroides fragilis and the expression of TNF-α, IL-1β, IL-6 and IL-8.
Methods :Male mice（BALB/c） were randomly divided into 4 groups: positive control （group C）, saline（group S）,TREM-1vshRNA(group T) and GFPvshRNA control vshRNA (group G) groups. Bacteroides fragilis (25mg/ kg) was injected via caudal veins in each group to establish the murine septic model. The expression of TREM-1, tumor necrosis factor alpha (TNF-α), IL-1β,lL-6, IkBa, pDAP12 and NF-κBp65 in spleen was observed in each group.
Results:In comparison with group C there was marked elevation of expession of TREM-1mRNA and protein in group T (P＜0.01).Compared to group C there was marked elevation of TNF-α, IL-1β and IL-6 content in splenic cells of groups T,G and S (P＜0.01).The level of TNF-α, IL-1β and IL-6 in splenic cells of group T was markedly lower than that of groups S and G (P＜0.01).In splenic cells of group S,pDAP12 and NF-κBP 65 protein expression was markedly increased compared to group T; the expression of 1κBa protein in splenic cells of groups was decreased.
Conclusions:The interference of TREM-1 signal pathway by TREM-1vshRNA may inhibit the genetic transcriptions of inflammatory factors, such as TNF-α,IL-1β ,IL-6 by downregulating the expression of DAP12, so to stablize the compound of IkBa/NF-κB, can inhibit the inflammatory reaction induced by Bacteroides fragilis.