原花青素调控miR-21表达对糖尿病视网膜病变大鼠血管内皮细胞功能及视网膜神经节细胞的保护机制研究

Proanthocyanidins regulate the expression of miR-21 on vascular endothelial cell function and retinal ganglion cells in rats with diabetic retinopathy

目的观察原花青素对miR-21的影响,探讨原花青素对糖尿病视网膜病变(diabetic retinopathy,DR)大鼠血管内皮细胞功能及视网膜神经节细胞的保护机制。方法体外培养人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs),采用不同浓度(5、25、50、75、100 mg/L)原花青素处理细胞24 h后,用CCK-8法检测细胞增殖活性并筛选出原花青素50 mg/L进行后续实验,采用细胞划痕实验法测定细胞迁移能力,采用定量聚合酶链反应(polymerase chain reaction,PCR)检测miR-21的表达;将30只大鼠分为正常组、模型对照组和原青花素250 mg/kg组,正常组不经处理,模型对照组和原青花素250 mg/kg组经过腹腔注射链脲佐菌素诱导大鼠DR,原青花素250 mg/kg组经过灌胃250 mg/kg原花青素干预2周,采用显微镜观察视网膜细胞情况,TUNEL法测定神经节细胞凋亡情况,定量PCR检测miR-21的表达。结果原花青素抑制HUVECs增殖的效果呈浓度依赖性,5 mg/L组与对照组差异无统计学意义(P>0.05),25 mg/L、50 mg/L、75 mg/L和100 mg/L组与对照组比较,差异均有统计学意义(P<0.05)。50 mg/L迁移能力较对照组减弱,miR-21表达下调(P<0.05);模型对照组和原花青素250 mg/kg组大鼠视网膜miR21表达量高于正常组,模型对照组高于原花青素250 mg/kg组(P<0.05)。模型对照组和原花青素250 mg/kg组大鼠视网膜神经节细胞凋亡指数大于正常组,模型对照组大于原花青素250 mg/kg组。结论原花青素能够抑制血管内皮细胞增殖、迁移,并抑制DR大鼠视网膜神经节细胞凋亡,保护视网膜病变,其机制可能与下调miR-21表达有关。

Objective To observe the effect of proanthocyanidins on miR-21,and explore the protective mechanism of proanthocyanidins on vascular endothelial function and retinal ganglion cells in diabetic retinopathy rats.Methods To observe the effect of proanthocyanidins on miR-21,and explore the protective mechanism of proanthocyanidins on vascular endothelial function and retinal ganglion cells in diabetic retinopathy rats.Results The effect of proanthocyanidins on the proliferation of human umbilical vein endothelial cells(HUVECs)was concentration-dependent.There was no significant difference between the 5 mg/L group and the control group(P>0.05).Compared with the control group,the 25 mg/L,50 mg/L,75 mg/L and 100 mg/L groups had statistically significant differences(P<0.05).The migration ability of 50 mg/L was weaker than that of the control group(P<0.05),and the expression of miR-21 was down-regulated(P<0.05).The expression of miR-21 in the retina of rats in the model control group and the procyanidin 250 mg/kg group were higher than that in the normal group,and the model control group was higher than the procyanidin 250 mg/kg group(P<0.05).The apoptosis index of retinal ganglion cells in the model control group and the procyanidin 250 mg/kg group was greater than that of the normal group,and the model control group was greater than the procyanidin 250 mg/kg group.Conclusion Proanthocyanidins can inhibit the proliferation and migration of vascular endothelial cells,and inhibit the apoptosis of retinal ganglion cells in diabetic retinopathy rats,and protect retinopathy.The mechanism may be related to down-regulation of miR-21 expression.