Effects of pigment epithelium derived factor on the expressions of Caspase-3 and Bax in retinal tissues of rat models with optic nerve injury

WANG Bin; ZHAO Junbo; SU Chunyong

doi:10.3969/j.issn.1002-7386.2017.13.003

Abstract：Objective To investigate the effects of pigment epithelium derived factor (PEDF) on the expressions of Caspase-3 and Bax in retinal tissues of rat models with optic nerve injury.Methods Ninety healthy female SD rats were randomly divided into three groups:blank control group,model group and PEDF group (experimental group),with 30 rats in each group.Except for blank control group,the rat models with optic nerve injury were established in model group and experimental group.After the animal models were successfully established,the left eye was taken as experimental specimen.The balanced salt solution 5μl was injected into vitreous cavity of rats in model group,and PEDF 5μl (0.2μg/μl) was injected into vitreous cavity of rats in experimental group,moreover,the balanced salt solution 5μl and PEDF 5μl was again injectd into vitreous cavity of rats in modle group and experimental group,respectively on 1 week and on 2 week.On the third week,the retinal tissues of rats in three groups were taken,and the ultrastructural changes of retinal tissues were observed by electron microscopy,and the expression levels of Caspase-3,Bax and the apoptosis of retinal ganglion cells were observed by immunohistochemical staining.Results The mitochondria edema and cytoplasm condensed axon swelling were observed in model group and experimental group.TUNEL cell apoptosis monitoring showed that it was negative in blank control group,however,positive staining of RGCs was found in model group and experimental group,moreover,the positive expression levels of RGCs in experimental group were significantly lower than those in model group (P<0.05).The expression of Caspase-3 was weakly positive in experimental group,which was strong positive in model group.the optical density value of Caspase-3 in experimental group was significantly lower than that in model group (P<0.05).Moreover the expression levels of Bax in model group and experimental group were significantly higher than those in blank control group (P<0.05).However the expression levels of Bax in experimental group were significantly lower than those in model group (P<0.05).Conclusion The Caspase-3 and Bax are important factors inducing apoptosis of RGCs cells.The intervention therapy of PEDF can reduce the expression levels of Caspase-3 and Bax so as to relieve the damage of RGCs.