Effects of oxidative stress on neuronal apoptosis and protein expression of c-myc after intracerebral hemor rhage

Objective To investigate the relationship between oxidative stress and neuronal apoptosis after intracerebral hemorrhage (ICH),and the influence of oxidative stress on c-myc expression. Methods Eighty-four male SD rats of 7-week-old were selected and randomly divided into sham operation group,model group,MPEG-SOD group,with 28 rats in each group.Intracerebral hemorrhage model was induced by autologous blood injection.Rats in MPEG-SOD group were injected with MPEG-SOD before modeling.The neurological deficit score (NDS) was measured at 12 h,1 d,3 d and 7 d after the operation.The water content of brain tissue was measured,and the content of malondialdehyde (MDA) and superoxide dismutase (SOD) in brain was measured by spectrophotometric method.The expression of nuclear factor-kappa B (NF-κB) p65 positive cells was detected by immunohistochemistry.The apoptosis of neurons was measured by TUNEL and the expression of c-myc protein was detected by Western blot. Results Compared with the sham-operated group,the NDS score and SOD activity at each time points were obviously decreased,while the water content in the brain tissue,MDA content,c-myc protein expression,NF-κB p65 and TUNEL-positive cells in the model group were significantly increased (P<0.05),which reached the peak 3d after the operation.Compared with the model group,the NDS score,SOD activity,water content in the brain tissue,MDA content,c-myc protein expression and TUNEL,NF-κB p65 positive cells in the MPEG-SOD group were significantly decreased (P<0.05).The expression of c-myc protein and TUNEL-positive cells in the brain tissue was correlated (R=0.83 in model group,as well as r=0.91 in MPEG-SOD group,P<0.05). Conclusion The oxidative stress-induced apoptosis of neurons may be related to the initiation of apoptosis-related gene c-myc after intracerebral hemorrhage.