LncRNA ENST00000532153.1 Alleviates Podocyte Injury by Inhibiting PARP1-Mediated PARylation of ATF3 in Diabetic Kidney Disease

Background: Podocyte injury plays a crucial role in the progression of diabetic kidney disease (DKD), and the involvement of long non-coding RNAs (lncRNAs) in DKD and podocyte injury is emerging. Our previous RNA-seq results indicated a decrease in the expression of lncRNA ENST00000532153.1(lncRNA 153) in DKD. However, the functional role and underlying mechanisms of lncRNA 153 in DKD have to be elucidated. Methods: Real-time PCR and FISH were used to detect lncRNA 153 expression level, while RNA-pulldown and mass spectrometry analysis identified its binding proteins. Subsequently, endoplasmic reticulum (ER) stress, apoptosis, and podocyte injury were assessed through Western blot, real-time PCR, immunofluorescence, and flow cytometry. RNA-seq results were combined with multiple databases to find downstream transcription factors. Co-IP, PLA, and molecular docking analyses were employed to validate the interaction between PARP1 and ATF3. Chromatin immunoprecipitation and dual-luciferase reporter assay were utilized to investigate the role of lncRNA 153 and PARP1 in transcriptional regulation. Results: LncRNA 153 is down-regulated in DKD and correlated with clinical parameters. Meanwhile, overexpression of lncRNA 153 mitigated podocyte injury caused by high glucose. Subsequently, PARP1 was then identified as the binding protein of lncRNA 153 through filtration selection. Knockdown of PARP1 in podocytes under HG levels inhibited ER stress and apoptosis, thereby alleviating podocyte injury both in vitro and in vivo. Furthermore, we found that ATF3 is a novel interacting protein of PARP1, the interaction between them shown to be involved in regulation of gene transcription and regulated by lncRNA 153. Conclusion: Overall, these data suggest that lncRNA 153 binds to PARP1, inhibiting its interaction with ATF3 and subsequently reducing the transcriptional activity of ATF3, ultimately alleviating podocyte injury in DKD by suppressing ER stress and apoptosis. Therefore, our study suggests that lncRNA 153 and PARP1 may be attractive therapeutic targets for DKD. Funding: Government Support – Non-U.S.