The Preliminary Study Of Protein Coded By Mitochondrial DNA In The Process Of Inflammation

Objective Trauma is a leading factor which causes SIRS(systemic inflammatoryresponse syndrome),even MODS(multiple organ dysfunction syndrome). It is wellknown that there is a large number of broken mitochondria after trauma. The proteincoded by mitochondrial DNA in mitochondria is released into the circulation and cantrigger inflammation through FPR. Cytochrome b as one of the protein should be aimportant factor which causes inflammation without microorganism.This study have3parts.:First, analyses the relativity between Cytochrome b and inflammation.; Second,Cytochrome b activates macrophage in vivo; Third, Mice were injectedintra-articularly with cytochrome c to induce arthritis. The whole experiment studythe role of cytochrome c in inflammation to provide the new idea for the preventionand treatment of SIRS and MODS afer severe trauma.Methods The fist part of experiment: Preparation of femoral shaft fracture ratmodel(n=27), after trauma in1hour,2hours,4hours,8hours,12hours,24hoursand36hours observed the expression levels of TNF-alpha、IL-1、IL-6in peripheralblood by enzyme-linked immunosorbent assay (ELISA); The second part: in vitro,the rat peritoneal macrophages can be devied into medium control group; mtDNA(10ug/ml) group; Cyt-b (0.1ug/ml) group; Cyt-b (1ug/ml) group and Cyt-b (10ug/ml)group. In1hour,2hours,4hours,8hours,12hours,24hours and36hours observedthe expression levels of TNF-alpha、IL-1、IL-6in inoculum by enzyme-linkedimmunosorbent assay (ELISA); The third part: the rats injected intra-articularly weredivided into3groups;①buffer group the②Cyt-b (10ug/ml) group③mtDNA(10ug/ml) group. All the rats were killed5days after injection and the knee jointswere evaluated histopathologically. Results The concentration of Cyt-b in peripheral blood reach peak in4hourafter trauma, then gradually decline slowly;The concentration of TNF-α reach peakin6hour,of IL-10、IL-6reach peak in6hour,then gradually decline slowly; Therelativity between Cyt-b and inflammation is positive. The control group、Cyt-b(0.1ug/ml) group and Cyt-b (1ug/ml) group show no significant changes at each timepoint of peripheral blood levels of inflammatory factors; Cyt-b (10ug/ml) group andmtDNA (10ug/ml) group can increase the expression of TNF-α、IL-1、IL-6. Theknees of the rats injected intra-articularly with Cyt-b (10ug/ml) and mtDNA (10ug/ml)can be observed influx of inflammation cells and synovial hypertrophyhistopathologically. The frequency and severity of arthritis in Cyt-b (10ug/ml) groupand mtDNA (10ug/ml) group are higer than control group.Conclusions The relativity between Cyt-b and inflammation is positive. Cyt-b(10ug/ml) group and mtDNA (10ug/ml) group can activate macrophage and canstimulate macrophages to produce TNF-α、IL-1、IL-6, also can induce rat arthritis invivo.