Published online Feb 15, 2024. doi: 10.4239/wjd.v15.i2.260
Peer-review started: September 24, 2023
First decision: December 6, 2023
Revised: December 13, 2023
Accepted: January 15, 2024
Article in press: January 15, 2024
Published online: February 15, 2024
Processing time: 132 Days and 18.3 Hours
Podocyte apoptosis plays a vital role in proteinuria pathogenesis in diabetic nephropathy (DN). The regulatory relationship between long noncoding RNAs (lncRNAs) and podocyte apoptosis has recently become another research hot spot in the DN field. LncRNAs are a potential therapeutic target for alleviating DN development to search for novel lncRNAs and alter the expression of specific lncRNAs.
We here investigated lncRNA expression profiles and the associated competing endogenous RNA (ceRNA) network using high-throughput RNA-sequencing (RNA-seq) technologies in normal glucose (5.5 mmol/L, NG group) and high glucose (25 mmol/L, HG group) cultured mouse podocytes. Then, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were conducted to determine the function of differentially expressed lncRNAs.
The present study investigated the function and underlying molecular mechanism of novel lncRNAs in endoplasmic reticulum stress (ERS)-podocyte apoptosis, providing the hope of developing a new and effective therapeutic strategy against DN.
Using NG or HG-cultured podocytes, the cellular functions and exact mechanisms underlying the regulatory effects of lncRNA protein-disulfide isomerase-associated 3 (Pdia3) on podocyte apoptosis and ERS were explored. LncRNA Pdia3 and miR-139-3p expression were measured through quantitative real-time polymerase chain reaction. Relative cell viability was detected through the cell counting kit-8 colorimetric assay. The podocyte apoptosis rate in each group was measured through flow cytometry. The interaction between lncRNA Pdia3 and miR-139-3p was examined through the dual luciferase reporter assay. Finally, western blotting was performed to detect the effect of lncRNA Pdia3 on podocyte apoptosis and ERS via miR-139-3p.
LncRNA Pdia3 was down-expressed in HG-cultured podocytes. LncRNA Pdia3 overexpression attenuated podocyte apoptosis and ERS in HG-cultured podocytes. LncRNA Pdia3 regulated podocyte apoptosis by serving as a ceRNA of miR-139-3p. Inhibition of miR-139-3p attenuated podocyte apoptosis and ERS in HG-cultured podocytes.
This study provided evidence that lncRNA Pdia3 downregulation is a significant contributing factor for podocyte apoptosis in DN. LncRNA Pdia3 downregulation could induce ERS and podocyte injury by serving as a ceRNA of miR-139-3p, thereby leading to DN progression.
In the future, whether the findings obtained in vitro can be applied to in vivo DN needs to be investigated. We intend to detect the expression and underlying molecular mechanism of lncRNA Pdia3 in DN patients.