Department of Ophthalmology, Weifang Eye Hospital, Weifang, China.
Eur Rev Med Pharmacol Sci. 2019 Aug;23(3 Suppl):9-16. doi: 10.26355/eurrev_201908_18621.
To explore the effects of miR-21 on the rats with proliferative diabetic retinopathy by regulating the transforming growth factor-beta (TGF-β) signaling pathway.
A total of 36 Sprague-Dawley rats were randomly divided into the normal group (n=12), model group (n=12), and inhibitor group (TGF-β signaling inhibitor) (n=12). No treatment was performed in the normal group, the diabetic retinopathy model was established in the model group, and the model was established in the inhibitor group after the intraperitoneal injection of the inhibitor. Then, the materials were sampled for detection. In each group, the retinal morphology was observed via hematoxylin-eosin (HE) staining, the expressions of TGF-β1 and Smad3 were detected via immunohistochemistry, the relative protein expression levels of phosphorylated Smad3 (p-Smad3) and TGF-β were determined via Western blotting, the expression of miR-21 was detected via quantitative Polymerase Chain Reaction (qPCR), and the hemodynamic indicators of the ocular tissues were detected using the color Doppler ultrasonography.
The HE staining results revealed that the rats in the model group had evident retinal damage, which could be effectively improved using the inhibitor. According to the immunohistochemistry detection results, the positive expression level of TGF-β1 was substantially raised in both model group and inhibitor group compared with that in the normal group (p<0.05), and it was notably lower in the inhibitor group than that in the model group (p<0.05). Moreover, the three groups did not differ in the positive expression level of Smad3 (p>0.05). The Western blotting results showed that the model and inhibitor groups had remarkably higher relative protein expression levels of p-Smad3 and TGF-β1 than the normal group (p<0.05), and they were markedly lowered in the inhibitor group compared with those in the model group (p<0.05). According to the qPCR results, the expression level of miR-21 was notably elevated in both model group and inhibitor group compared with that in the normal group (p<0.05), and there was no difference in the expression level of miR-21 between the former two groups (p>0.05). Finally, based on the color Doppler ultrasonography findings, the levels of the hemodynamic indicators substantially declined in both model group and inhibitor group compared with those in the normal group (p<0.05), and they were notably higher in the inhibitor group than those in the model group.
We found that miR-21 regulates the TGF-β signaling pathway to affect the hemodynamics in the rats with proliferative diabetic retinopathy.
探讨 miR-21 通过调控转化生长因子-β（TGF-β）信号通路对增生性糖尿病视网膜病变大鼠的影响。
将 36 只 Sprague-Dawley 大鼠随机分为正常组（n=12）、模型组（n=12）和抑制剂组（TGF-β 信号抑制剂）（n=12）。正常组不做处理，模型组建立糖尿病视网膜病变模型，抑制剂组造模后腹腔注射抑制剂。然后取样检测。各组均采用苏木精-伊红（HE）染色观察视网膜形态，免疫组化法检测 TGF-β1 和 Smad3 的表达，Western blot 法检测磷酸化 Smad3（p-Smad3）和 TGF-β的相对蛋白表达水平，qPCR 法检测 miR-21 的表达，彩色多普勒超声检测眼组织血流动力学指标。
HE 染色结果显示，模型组大鼠视网膜损伤明显，抑制剂可有效改善。免疫组化检测结果显示，模型组和抑制剂组 TGF-β1 阳性表达水平均明显高于正常组（p<0.05），抑制剂组明显低于模型组（p<0.05）。而且三组 Smad3 阳性表达水平无差异（p>0.05）。Western blot 结果显示，模型组和抑制剂组 p-Smad3 和 TGF-β1 的相对蛋白表达水平明显高于正常组（p<0.05），抑制剂组明显低于模型组（p<0.05）。qPCR 结果显示，模型组和抑制剂组 miR-21 的表达水平均明显高于正常组（p<0.05），前两组之间表达水平无差异（p>0.05）。最后，根据彩色多普勒超声检查结果，模型组和抑制剂组的血流动力学指标水平均明显低于正常组（p<0.05），抑制剂组明显高于模型组。
我们发现 miR-21 通过调控 TGF-β 信号通路影响增生性糖尿病视网膜病变大鼠的血流动力学。
