Concerning SIRS injury carries a disproportionately high morbidity and mortality in the elderly to re-search whether Interleukin-6 be risk or protective inflammatory cytokine as different age mice suffered burn and sepsis.Methods We used TBSA burn and burn adding sepsis(S.pneumoniae) mice model to simulate clinic pathological process.IL-6 knock out is used for evaluating the role of Il-6 in this process.we used wild type C56 /BL6 male and IL-6 knock out mice in 2 months and 14 months respectively.In addition to observation of cardiac function,morphology and pathology,we analyzed the IL-6 related cell signal protein: the transcription factor signal transducer and activator of transcription 3 (STAT3) ,the phospho-stat3 (p-stat3) ,the sarco(endo) plasmic reticulum Ca2 + -ATPase 2a (SER-CA2a) ,the suppressor of cytokine signaling 3 (socs3) ,inducible NO synthase (iNOS) .As same time,to isolate car-diomyocytes to measure [Ca2 +]i(intracellular calcium concentrations) .Result Burn complicated by sepsis promoted [Ca2+]i overloading,inflammatory injury and decreased cardiac contractility.Age was a promoter for this procedure.IL-6 deficiency could attenuated this injury process.But the old Il-6 knockout mice didn’t get more benefit like the young,although the aged Il-6 knock out mice lead to milder inflammation in heart pathology.Excepting iNOS,the variations of STAT3,p-stat3,SERCA2a,socs3 was related to cardiac dysfunction,inflammatory injury,and [Ca2 +]i overloading.Conclusions The cytokine Il-6 is a risk factor in burn and sepsis pathogenesis.But IL-6 deficiency seem to be disadvantageous for aged mice suffering from burn and sepsis.
