Abstract：
Diabetic nephropathy (DN) belongs to the major cause of end-stage kidney disease. We probed the functions of a microRNA miR-33a in inducing podocytes injury during childhood DN (CDN).
Kidney samples were collected from 20 children with DN. Matrix deposition and glomerular basement membranes thickness were examined by periodic acid-Schiff staining. Immunofluorescence staining was performed to assess kidney function-related proteins. MicroRNA (MiR)-33a mimic together with miR-33a inhibitor was transfected into podocytes for determining the roles of miR-33a. Glomerular podocyte apoptosis was determined by terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) staining along with flow cytometry.
Down-regulation of Nephrin and Podocin and increased podocyte apoptosis rate were observed in the glomerulus of CDN as well as podocytes treated with high glucose. MiR-33a was up regulated in the glomeruli and glucose-treated podocytes. Injury in podocytes was aggravated with miR-33a elevation but alleviated with miR-33a inhibition. Moreover, the expression of Sirtuin 6 (Sirt6) was decreased while the levels of notch receptor 1 (Notch1) and notch receptor 4 (Notch4) were elevated in the glomerulus and glucose-treated podocytes. Decreased level of Sirt6 upon glucose treatment was abrogated by miR-33a inhibition, and the podocytes injury induced by glucose exposure was relieved by Sirt6 via Notch signaling.
These findings indicated that miR-33a promoted podocyte injury via targeting Sirt6-dependent Notch signaling in CDN, which might provide a novel sight for CDN treatment. DOI: 10.52547/ijkd.7904.
Kidney samples were collected from 20 children with DN. Matrix deposition and glomerular basement membranes thickness were examined by periodic acid-Schiff staining. Immunofluorescence staining was performed to assess kidney function-related proteins. MicroRNA (MiR)-33a mimic together with miR-33a inhibitor was transfected into podocytes for determining the roles of miR-33a. Glomerular podocyte apoptosis was determined by terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) staining along with flow cytometry.
Down-regulation of Nephrin and Podocin and increased podocyte apoptosis rate were observed in the glomerulus of CDN as well as podocytes treated with high glucose. MiR-33a was up regulated in the glomeruli and glucose-treated podocytes. Injury in podocytes was aggravated with miR-33a elevation but alleviated with miR-33a inhibition. Moreover, the expression of Sirtuin 6 (Sirt6) was decreased while the levels of notch receptor 1 (Notch1) and notch receptor 4 (Notch4) were elevated in the glomerulus and glucose-treated podocytes. Decreased level of Sirt6 upon glucose treatment was abrogated by miR-33a inhibition, and the podocytes injury induced by glucose exposure was relieved by Sirt6 via Notch signaling.
These findings indicated that miR-33a promoted podocyte injury via targeting Sirt6-dependent Notch signaling in CDN, which might provide a novel sight for CDN treatment. DOI: 10.52547/ijkd.7904.
摘要：
背景：糖尿病肾病（DN）是终末期肾病的主要病因。我们探讨了microRNAmiR-33a在儿童DN（CDN）诱导足细胞损伤中的功能。
方法：收集20例DN患儿的肾脏样本。通过高碘酸希夫染色检查基质沉积和肾小球基底膜厚度。进行免疫荧光染色以评估肾功能相关蛋白。将微小RNA(MiR)-33a模拟物与miR-33a抑制剂一起转染到足细胞中以确定miR-33a的作用。通过末端脱氧核苷酸转移酶(TdT)dUTP尼克末端标记(TUNEL)染色以及流式细胞术确定肾小球足细胞凋亡。
结果：在高糖处理的CDN肾小球和足细胞中观察到Nephrin和Podocin的下调和足细胞凋亡率增加。MiR-33a在肾小球和葡萄糖处理的足细胞中上调。在足细胞中的损伤随着miR-33a的升高而加重,但随着miR-33a的抑制而减轻。此外，在肾小球和葡萄糖处理的足细胞中，Sirtuin6（Sirt6）的表达降低，而notch受体1（Notch1）和notch受体4（Notch4）的水平升高。葡萄糖处理后降低的Sirt6水平被miR-33a抑制消除，Sirt6通过Notch信号缓解了葡萄糖暴露引起的足细胞损伤。
结论：这些研究结果表明，miR-33a在CDN中通过靶向Sirt6依赖性Notch信号促进足细胞损伤，这可能为CDN治疗提供新的视野。DOI:10.52547/ijkd.7904。
方法：收集20例DN患儿的肾脏样本。通过高碘酸希夫染色检查基质沉积和肾小球基底膜厚度。进行免疫荧光染色以评估肾功能相关蛋白。将微小RNA(MiR)-33a模拟物与miR-33a抑制剂一起转染到足细胞中以确定miR-33a的作用。通过末端脱氧核苷酸转移酶(TdT)dUTP尼克末端标记(TUNEL)染色以及流式细胞术确定肾小球足细胞凋亡。
结果：在高糖处理的CDN肾小球和足细胞中观察到Nephrin和Podocin的下调和足细胞凋亡率增加。MiR-33a在肾小球和葡萄糖处理的足细胞中上调。在足细胞中的损伤随着miR-33a的升高而加重,但随着miR-33a的抑制而减轻。此外，在肾小球和葡萄糖处理的足细胞中，Sirtuin6（Sirt6）的表达降低，而notch受体1（Notch1）和notch受体4（Notch4）的水平升高。葡萄糖处理后降低的Sirt6水平被miR-33a抑制消除，Sirt6通过Notch信号缓解了葡萄糖暴露引起的足细胞损伤。
结论：这些研究结果表明，miR-33a在CDN中通过靶向Sirt6依赖性Notch信号促进足细胞损伤，这可能为CDN治疗提供新的视野。DOI:10.52547/ijkd.7904。
