Notch1和多聚二磷酸腺苷核糖聚合酶-1在糖尿病小鼠视网膜中的表达

Expressions of Notch1 and poly（adenosine diphosphate-ribose） polymerase 1 in mouse retina with diabetes mellitus

背景 多聚二磷酸腺苷核糖聚合酶-1（PARP-1）在糖尿病视网膜病变（DR）发生过程中具有重要作用,而Notch1是生物体重要的信号转导通路,可能参与对视网膜新生血管性疾病的拮抗过程,Notch1是否参与了DR的发生还未得到证实. 目的 探讨Notch1、Dll4、PARP-1、Akt、核因子-κB（NF-κB）及caspase-3在糖尿病小鼠视网膜组织及高糖视网膜血管内皮细胞（RVECs）中的表达. 方法 建立糖尿病小鼠模型,应用免疫组织化学法和Western blot法检测Notch1、Dll4、PARP-1、Akt、NF-κB及caspase-3在糖尿病小鼠视网膜组织及RVECs的表达.结果 Notch1、Dll4、p-Akt在糖尿病小鼠视网膜组织中的表达量比正常对照组明显降低,而PARP-1、caspase-3在糖尿病小鼠视网膜组织中的表达量比正常对照组明显增加,差异均有统计学意义（均P＜0.05）,但NF-κB的表达量无明显变化,差异无统计学意义（t=0.748,P=0.530）.RVECs中Notch1、p-Akt的表达量随葡萄糖浓度的增高而增加,而剪切型PARP-1、caspase-3的表达量则随葡萄糖浓度的增高而降低,在葡萄糖浓度为30 mmol/L时上述变化最显著,与正常对照组比较差异均有统计学意义（均P＜0.05）,而NF-κB的表达量无明显变化. 结论 在糖尿病小鼠视网膜中,剪切型PARP和caspase-3蛋白的表达上调,但Notch1、p-Akt蛋白的表达量下调.剪切型PARP和caspase-3表达量随葡萄糖浓度的增高而增加,Notch1、p-Akt则相反.

Background Poly（adenosine diphosphate-ribose） polymerase 1 （PARP-1） plays an important role in the pathogenesis of diabetic retinopathy （DR）,and Notch1 signal pathway is one of the important signal transduction pathways in the organism which may antagonize retinal vascular diseases.However,if Notch1 signaling pathway is involved in pathogenesis of DR has not been confirmed yet.Objective This study was to investigate the expressions of Notch1,Dll4,PARP-1,Akt,nuclear factor-κB （NF-κB） and caspase-3 in the retina of diabetic mouse model and retinal vascular endothelial cells （RVECs） under the high glucose.Methods The expressions of Notch1,Dll4,PARP-1,Akt,NF-κB and caspase-3 in the retina of diabetic mouse models were investigated using immunochemistry and Western blot method after the diabetic mouse models were established.And these proteins were detected in retinal RVECs under the high glucose by Western blot.Results The expressions of Notch1,Dll4 and phosphorylated Akt （p-Akt） in retinas reduced significantly and simultaneously companied with increases of PARP-1 and caspase-3 in diabetic mice compared with normal mice （all at P〈0.05）.However,no obvious change was found in the expression of NF-κB （P〉0.05）.Expressions of Notch1 and p-Akt in RVECs increased with the increase of glucose concentration,but expressions of cleaved PARP-1 and caspase-3 decreased,especially in the 30 mmol/L group,showing significant differences in comparison with the normal control group （all at P〈0.05）.But no altering of NF-κB expression was seen in the mice with diabetes mellitus.Conclusions The expressions of cleaved-PARP-1 and caspase-3 in the retinas is up-regulated,but the expressions of Notch1 and p-Akt are down-regulated in diabetic mice.