Abstract:Objective: This study was to investigate the effects of sericin on the inhibition of retinal neuron apoptosi via regulation of JNK signaling pathway in diabetic rat. Methods:The diabetic rat models were established by feeding high lipid foods and intraperitoneal injection of small-dose streptozotocin. Rats were randomly divided into three groups, sericine-treatment group, diabetes model group and normal control group. The sericin solution dissolved in normal saline solution 2.4 g·kg-1·d-1 was used for 35 days in gavage method in the sericin-treated group. The rats were sacrificed by an overdose of anesthesia and retinal sections were prepared. The expressions of phosphorylation c-Jun N-terminal kinase( p-JNK),Cytochrome(Cyt-c)and Cysteine aspartate kinase 9(caspase-9)in retinas in protein levels were detected by Western blot . The activity of Cysteine aspartate kinase 3(caspase-3)in the retina was detected by spectrophotometry. TUNEL staining was employed to detect retinal neuron apoptosis. Results:The relative expression levels of p-JNK, Cyt-c and caspase-9 proteins, the activity of caspase-3,the apoptotic index(AI) in rat retinas in the sericintreated group were significantly lower than those in the diabetic model group (all at P<0.05). Conclusion:Sericin can inhibit retinal neuron apoptosis by regulating JNK signaling pathway in diabetic rats.
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