microRNA let-7i-5p aggravates kidney fibrosis via targeting GALNT1.

Renal fibrosis poses critical health problem. We aimed to investigate role of let-7i-5p in renal fibrosis. In silico reproduction of Mouse Kidney FibrOmics browser was used to identify potential target of let-7i-5p. In vivo validation was conducted in C57BL/6 mice with unilateral ureteral obstruction (UUO) and folic acid (FA) induction. In vitro validation was performed in transforming growth factor (TGF)-ß1-treated HK-2 cells. Mimics and inhibitors of let-7i-5p, and target gene polypeptide N-acetylgalactosaminyltransferase 1 (GALNT1) were monitored by RT-PCR and Western blotting. Fibrosis markers, injury markers, and house-keeping genes were evaluated. Levels of interleukin (IL)-6, IL-1ß, and tumor necrosis factor (TNF)-α in serum and media were measured by ELISA. In silico analysis showed gradual increase of let-7i-5p and decrease of GALNT1 over time and the combination was validated both in mouse and human miR-gene target prediction databases. Expression of GALNT1 decreased while expression of let-7i-5p increased in renal tissues of both UUO and FA mice. Serum IL-6, IL-1ß, and TNF-α levels were elevated in vivo. In vitro models revealed negative correlation between expression levels of let-7i-5p and GALNT1. Overexpression of let-7i-5p inhibited GALNT1 expression and reduced release of inflammatory factors. In conclusion, overexpression of GALNT1 may combat the inflammation induced by let-7i-5p.

Erratum to: "Fer exacerbates renal fibrosis and can be targeted by miR-29c-3p".

[This corrects the article DOI: 10.1515/med-2021-0319.].

Fer exacerbates renal fibrosis and can be targeted by miR-29c-3p.

AIM: Renal fibrosis (RF) is a common clinical condition leading to irreversible renal function loss. Tyrosine kinase proteins and microRNAs (miRs) are associated with pathogenesis and we aim to investigate the role of Fer and its partner miR(s) in RF. METHOD: In silico reproduction of Mouse Kidney FibrOmics browser was performed to identify potential miR(s) and target gene(s). In vivo validation was performed in C57BL/6 mice with unilateral ureteral obstruction (UUO). In vitro validation was performed in rat kidney fibroblast NRK-49F cells. Mimics and inhibitors of miR-29c-3p were constructed. The target gene Fer was monitored by RT-PCR and western blotting. The levels of interleukin (IL)-6, IL-1ß, and tumor necrosis factor (TNF)-α in serum and media were measured by ELISA. RESULTS: The Fer expression and protein level were gradually increased during 14 days of UUO modeling. miR-29c-3p expression was strongly correlated with that of Fer. In vivo validation showed increased expressions of fibrosis-associated genes and increased phospoho-Smad3 level in the UUO model. Fer-knockdown (KD) significantly decreased expressions of fibrosis-associated genes. Pharmaceutical inhibition of Fer showed similar effects to miR-29c-3p, and miR inhibition showed a significant decrease of excretion of inflammatory factors. CONCLUSION: Dysregulation of miR-29c-3p and Fer plays a role in RF. Pharmaceutical or genetic inhibition of Fer may serve as the potential treatment for RF.