Allitridum attenuates ischemia/reperfusion-induced apoptotic cell death by modulating expression of Bcl-2,Bax and NF-κB

AIM: To investigate the roles of Bcl-2,Bax and NF-κB in the anti-apoptosis effect of allitridum.METHODS: Sodium pentobarbital-anesthetized Sprague Dawley(SD) rats underwent 30 min of left anterior descending(LAD) coronary occlusion followed by 120 min of reperfusion.Forty-eight rats were randomly divided into three groups: control(CON,n=12),ischemia/reperfusion(I/R,n=18) group and allitridum pretreatment(AP,n=18) group.Twenty-four h before operation,allitridum was given to the AP group and saline was administered to the other groups.CON group underwent only sham operation,whereas the other two groups underwent I/R operation.Infarct size [IS/AAR(%)] was measured in the I/R group and AP group,and creatine kinase isoenzyme-MB(CK-MB),superoxide dismutase(SOD) and apoptosis index(AI) by TUNEL staining were measured in each group.DNA fragmentation agarose gel electrophoresis was conducted on isolated DNA and the expression of Bcl-2 and Bax protein and the activity of NF-κB were measured,respectively,by immunohistochemistry and electrophoretic mobility assay(EMSA) in each group.RESULTS: Allitridum pretreatment decreased the infarct size compared with that in I/R group [(21.8±1.5)% vs.(44.6±4.6)%,P0.01],CK-MB [(16.4±1.6) U/L vs.(34.1±1.8) U/L,P0.01].However,SOD levels in AP group were higher than those in I/R group [(2 337±215) U/mg pro vs.(1 219±187) U/mg pro,P0.01].AI in I/R group was higher than in AP group [(4.0±3.0)% vs.(7.0±1.2)%,P0.01],which was consistent with the result of DNA fragmentation agarose gel electrophoresis.No immunoreactivity of Bcl-2 was observed in CON group.Bcl-2 immunoreactivity was weakly expressed in the I/R group and strongly expressed in the peri-necrosis zone in the AP group.The expression of Bax significantly increased in I/R group but was weaker in the AP group.NF-κB binding activity was present at low levels in CON group but significantly increased in the I/R group.Allitridum markedly inhibited NF-κB binding in the I/R group.CONCLUSION: Allitridum has an obvious effect of protecting myocardium against I/R injury and decreasing infarcted zone.The protective effect is probably achieved through decreasing myocardium apoptosis in I/R injury and modulating the expression of Bcl-2 and Bax and the binding activity of NF-κB.