The Impact Of Cytokines And Propofol On Neutrophil Apoptosis

Objectives: 1 To observe the influences of IL-6, IL-10, and propofol on human neutrophils apoptosis, necrosis, and myeloperoxidase(MPO) release; 2 To observe the effects of IL-6, IL-10, and propofol on human neutrophils caspase-3 activation, and then try to clarify the molecular mechanisms of IL-6, IL-10, and propofol interfering with neutrophil apoptosis. Methods: Neutrophils from 20 healthy volunteers' venous blood were isolated and incubated in RPMI1640 cell culture medium. Neutrophils from every case were divided into 8 parts and added NS(control group), IL-6, IL-10, IL-6+IL-10, propofol, intralipid(the lipid vehicle of propofol), IL-6+propofol, IL-6+intralipid in culture respectively. After 24 hours of incubation, neutrophils apoptosis and necrosis were observed morphologically and apoptosis and necrosis index were calculated. MPO activity was measured by a biochemical method.Neutrophils from other 12 healthy volunteers were isolated, divided into 8 groups, given cytokines or drugs, and incubated, by the same way as that described above. After 18 hours of incubation, activated caspase-3 was measured using an analysis kit through flow cytometer.Results: Spontaneous neutrophil apoptosis was significantly inhibited when co-incubated with IL-6 (P<0.01). Neither IL-10, nor propofol, nor intralipid influenced neutrophil apoptosis when given alone. However, IL-10 and propofol but not intralipid counteracted inhibition of neutrophil apoptosis induced by IL-6 (P<0.01, P=0.028, and 0.515 respectively).IL-6 could increase neutrophil necrosis (P=0.005 compared with control group); IL-10, propofol, or intralipid had no effects on neutrophil necrosis, and could not reverse the increase of neutrophil necrosis caused by IL-6.IL-6 could increase neutrophil MPO release (P=0.016), but IL-10, propofol, or...