lncRNA ZEB1-AS1 Was Suppressed by p53 for Renal Fibrosis in Diabetic Nephropathy

The role of p53 in renal fibrosis is still controversial, and its underlying mechanisms remain not clear. Here, we showed that the pharmacological inhibition and genetic deletion of p53 in proximal tubular cells can attenuate renal dysfunction, tubular epithelial disruption, and interstitial fibrosis in db/db and STZ-induced diabetic nephrology (DN) mice. In human renal proximal tubule (human kidney 2 [HK-2]) cells, inhibition of p53 by PIF reduced the high glucose (HG)-induced extracellular matrix (ECM) accumulation and reversed the inhibitory effect of HG on mRNA expression levels of lncRNA zinc finger E-box binding homeobox1-antisense RNA 1 (ZEB1-AS1) and ZEB1. Interestingly, our results demonstrated that both lncRNA ZEB1-AS1 and ZEB1 exhibited an anti-fibrotic role, while ZEB1 is positively regulated by lncRNA ZEB1-AS1 during HG treatment. Mechanistically, lnc ZEB1-AS1 bound directly to H3K4 methyltransferase myeloid and lymphoid or mixed-lineage leukemia 1 (MLL1) and promoted H3K4me3 histone modification on ZEB1 promoter, which was reduced by HG treatment. ChIP analysis indicated the binding of p53 to the promoter region of lnc ZEB1-AS1. Furthermore, the findings were verified by the kidney biopsy samples from patients with DN. Taken all together, our results suggest that p53 may be a therapeutic target for renal fibrosis in DN.