葛花总黄酮对糖尿病小鼠视网膜神经细胞凋亡及相关基因Bax和Bcl-2的影响

Effects of Total Flavonoids from Flos Puerariae Lobatae on Retinal Neuronal Apoptosis and Related Genes Bax and Bcl-2 in Diabetic Mouse

目的:探讨葛花总黄酮(total flavonoids from Flos Puerariae Lobatae,TFF)对糖尿病小鼠视网膜神经细胞凋亡及凋亡相关基因Bax、Bcl-2表达的影响。方法:50只C57BL/6J小鼠随机分为正常对照组(Control组),糖尿病模型组(DM组),葛花总黄酮50 mg·kg^(-1)·d^(-1)组(TFFⅠ组)、100 mg·kg^(-1)·d^(-1)组(TFFⅡ组)和200 mg·kg^(-1)·d^(-1)组(TFFⅢ组)。采用脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(TUNEL)检测小鼠视网膜神经细胞的凋亡;透射电镜下观察视网膜神经节细胞超微结构的变化;免疫组织化学染色法检测视网膜中Bax、Bcl-2的表达。结果:与DM组比较,葛花总黄酮治疗组(TFFⅠ、TFFⅡ、TFFⅢ)小鼠视网膜神经细胞凋亡指数均降低。电镜下观察,葛花总黄酮治疗组神经节细胞超微结构得到改善。与DM组比较,TFFⅠ和TFFⅡ组Bax表达减弱,Bcl-2表达增强,Bcl-2/Bax比值升高。结论:葛花总黄酮可通过上调Bcl-2的表达和下调Bax的表达,抑制糖尿病小鼠视网膜神经细胞凋亡,发挥对糖尿病视网膜病变神经细胞的保护作用。

Objective To investigate the effect of total flavonoids from Flos Puerariae Lobata(TFF)on retinal neuronal apoptosis and expression of apoptosis-related genes Bax and Bcl-2 in diabetic mouse.Methods 50 C57BL/6J mice were randomly divided into 5 groups:normal control group,diabetic model group(DM),TFF 50 mg·kg^(-1)·d^(-1) group(TFFⅠ),TFF 100 mg·kg^(-1)·d^(-1) group(TFF Ⅱ)and TFF 200 mg·kg^(-1)·d^(-1) group(TFF Ⅲ).Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling(TUNEL)was used to detect the apoptosis of retinal neurons in retina.Ultrastructural changes of retinal ganglion cellswere observed under transmission electron microscope.The expressions of Bax and Bcl-2 in retina were detected by immunohistochemical staining.Results Compared with the model group,the apoptosis index in TFF treatment group(TFF Ⅰ,TFF Ⅱ and TFF Ⅲ)decreased.Observed under the electron microscope,the ultrastructure of ganglion cell in TFF treatment groups was improved.Compared with the model group,the expression of Bax decreased,the expression of Bcl-2 increased,and the ratio of Bcl-2/Bax increased in the TFF Ⅰ and TFF Ⅱ groups.Conclusion The total flavonoids from Flos Puerariae Lobatae can inhibit retinal neuronal apoptosis through up-regulating Bcl-2 expression and down-regulating Bax expression in diabetic mouse retina.It plays a protective effect on nerve cells in diabetic retinopathy.