Inhibition of the lncRNA 585189 prevents podocyte injury and mitochondria dysfunction by promoting hnRNP A1 and SIRT1 in diabetic nephropathy

Abstract Podocyte damage is a crucial cause for diabetic nephropathy and end-stage renal disease. Moreover, mitochondria play an indispensable role in diabetic nephropathy and high glucose-associated podocyte damage. Through RNA sequencing, we firstly discovered that long non-coding RNA (lncRNA) ENST00000585189.1 (lncRNA 585189), was up-regulated in the plasma of patients diagnosed with DN, accompanied with higher albumin/creatinine ratios. Additionally, RNA-FISH in the tissues and immortalized human podocytes identified that the variation of lncRNA 585189 was mainly located in podocytes. In podocytes under the high glucose condition, we found that the silence of lncRNA 585189 expression not only decreased the production of ROS, rescued mitochondrial morphology and the alteration of the mitochondrial membrane potential, but also restored the podocyte damage, reversing the aberrant expression of ZO-1 and Desmin. Through bioinformatics analysis, lncRNA 585189 was predicted to combined with hnRNP A1 at the nt224 motif, which was demonstrated by RIP, pull-down and EMSA. Meanwhile, under high glucose condition, declined hnRNP A1 can be rescued by repressing lncRNA 585189. With the treatment of cloheximide (CHX) and MG-132, we also verified that lncRNA 585189 depressed the stability of hnRNPA1. Intriguingly, hnRNP A1 oppositely promoted the expression of lncRNA 585189. Moreover, RIP, pull-down, co-IP and actinomycin D (ActD) verified that hnRNP A1 simultaneously bound with the mRNA and protein of SIRT1 and promote the stability of SIRT1. Besides, lncRNA 585189 repressed SIRT1 via hnRNPA1, impeding SIRT1 recuperating mitochondrial abnormity and podocyte damage induced by high glucose. Collectively, our findings revealed that lncRNA 585189 combined with hnRNPA1 at nt224 and depressed the expression of hnRNP A1 and subsequently decreased SIRT1 in transcriptional and translational level, leading to mitochondria dysfunction and podocyte injury in DN.