槲皮素对1型糖尿病肾病肾小管上皮细胞间质转分化的作用

Effect of quercetin on the mesenchymal transdifferentiation of renal tubular epithelial cells in type 1 diabetic nephropathy

关键词:  1型糖尿病肾病  肾小管上皮细胞间质转分化  槲皮素  大鼠实验

Key words:  type 1 diabetic nephropathy  renal tubular epithelial cell mesenchymal transdifferentiation  quercetin  rat experiment

摘要:

[目的] 研究槲皮素在1型糖尿病肾病（T1DN）肾小管上皮细胞间质转分化中的作用。[方法] 30只雄性SD大鼠随机分为3组：对照组、T1DN组和槲皮素组，每组10只。除对照组以外，其他大鼠空腹注射100 mg/kg链脲佐菌素，构建T1DN模型。槲皮素组大鼠灌胃100 mg/kg槲皮素，对照组和T1DN组大鼠灌胃同剂量的生理盐水，每日1次，持续8周。通过Masson和天狼星染色检测肾组织病理学变化；采用实时荧光定量聚合酶链反应（Real-time PCR）和蛋白质免疫印记法（Western blot）检测肾皮质中转化生长因子-β（TGF-β）/Smad信号通路、α-平滑肌肌动蛋白（α-SMA）、Snail和E-钙黏蛋白（E-cadherin）和基因的表达。[结果] 天狼星染色结果显示，对照组的肾组织结构完整，肾间质未见胶原纤维沉积，T1DN组肾组织结构破坏，间质胶原纤维沉积明显增加，槲皮素改善肾组织损伤，间质胶原纤维减少。Real-time PCR和Western blot结果显示，与对照组比较，T1DN组的TGF-β、Smad2/3、α-SMA、Snail蛋白和mRNA表达显著增加（P<0.05），E-cadherin的表达显著减少（P<0.05）。与T1DN组比较，槲皮素组的TGF-β、Smad2/3、α-SMA、Snail蛋白和mRNA表达显著降低（P<0.05），E-cadherin的表达显著增加（P<0.05）。[结论] 槲皮素可能通过降低TGF-β、Smad2/3、α-SMA、Snail的表达，促进E-cadherin的表达，从而抑制肾小管上皮细胞间质转分化和肾间质纤维化的发生发展。

Abstract:

[Objective] To study the role of quercetin in the mesenchymal transdifferentiation of renal tubular epithelial cells in type 1 diabetic nephropathy (T1DN).[Methods] Thirty male SD rats were randomly divided into 3 groups:control group (n=10),T1DN group (n=10) and quercetin group(n=10). Except for the control group,other rats were injected with 100 mg/kg streptozotocin on an empty stomach to construct a T1DN model. Rats in the quercetin group were given 100 mg/kg quercetin by intragastric administration,and rats in the control group and T1DN group were given the same dose of normal saline once a day for 8 weeks. Masson and Sirius staining were used to detect renal histopathological changes;Real-time PCR and Western blot were used to detect the expression of TGF-β/Smad signaling pathway,α-SMA,Snail and E-cadherin proteins and genes in the renal cortex.[Results] The results of Sirius staining showed that the renal tissue structure of the control group was intact,and there was no collagen fiber deposition in the renal interstitium. The renal tissue structure of the T1DN group was damaged,and the deposition of interstitial collagen fibers was significantly increased. Quercetin improves renal tissue damage and reduces interstitial collagen fibers. Real-time PCR and Western blot results showed that compared with the control group,the expression of TGF-β,Smad2/3,α-SMA,Snail protein and mRNA in the T1DN group increased significantly(P<0.05),and the expression of E-cadherin decreased significantly(P<0.05). Compared with the T1DN group,the expressions of TGF-β,Smad2/3,α-SMA,Snail protein and mRNA in the quercetin group were significantly reduced (P<0.05),and the expression of E-cadherin was significantly increased (P<0.05).[Conclusion] Quercetin may reduce the expression of TGF-β,Smad2/3,α-SMA and Snail,and promote the expression of E-cadherin,thereby inhibiting the mesenchymal transdifferentiation of renal tubular epithelial cells and the occurrence and development of renal interstitial fibrosis.