Histone H3K27 methyltransferase EZH2 regulates apoptotic and inflammatory responses in sepsis-induced AKI

Abstract

Rationale: The role of histone methylation modifications in renal disease, particularly in sepsis-induced acute kidney injury (AKI), remains unclear. This study aims to investigate the potential involvement of the histone methyltransferase zeste homolog 2 (EZH2) in sepsis-induced AKI and its impact on apoptosis and inflammation. Methods: We first examined the expression of EZH2 in the kidney of sepsis-induced AKI (LPS injection) mice and LPS-stimulated tubular epithelial cells. We next constructed the EZH2 knockout mice to further confirm the effects of EZH2 on apoptosis and inflammatory response in AKI. And the inflammatory level of epithelial cells can be reflected by detecting chemokines and the chemotaxis of macrophages. Subsequently, we constructed the EZH2 knocked-down cells again and performed Chromatin Immunoprecipitation sequencing to screen out the target genes regulated by EZH2 and the enrichment pathway. Then we confirmed the EZH2 target gene and its regulatory pathway in vivo and in vitro experiments. Experimental results were finally confirmed using another in vivo model of sepsis-induced AKI (cecal perforation ligation). Results: The study found that EZH2 was upregulated in sepsis-induced AKI and that silencing EZH2 could reduce renal tubular injury by decreasing apoptosis and inflammatory response of tubular epithelial cells. EZH2 knockout mice showed significantly reduced renal inflammation and macrophage infiltration. Chromatin immunoprecipitation sequencing and polymerase chain reaction identified Sox9 as a target of EZH2. EZH2 was found to be enriched on the promoter of Sox9. Silencing EZH2 resulted in a significant increase in the transcriptional level of Sox9 and activation of the Wnt/β-catenin signaling pathway. The study further reversed the effects of EZH2 silencing by silencing Sox9 or administering the Wnt/β-catenin inhibitor icg001. It was also found that Sox9 positively regulated the expression of β-catenin and its downstream pathway-related genes. Finally, the study showed that the EZH2 inhibitor 3-deazaneplanocin A significantly alleviated sepsis-induced AKI. Conclusion: Our results indicate that silencing EZH2 can protect renal function by relieving transcriptional inhibition of Sox9, activating the Wnt/β-catenin pathway, and attenuating tubular epithelial apoptosis and inflammatory response of the renal interstitium. These results highlight the potential therapeutic value of targeting EZH2 in sepsis-induced AKI.

The SOX4/EZH2/SLC7A11 signaling axis mediates ferroptosis in calcium oxalate crystal deposition-induced kidney injury

“…Moreover, the protective effect of EZH2 inhibition with 3-DZNep has been demonstrated in kidney injuries. In a model of sepsis-induced AKI, inhibition of EZH2 expression could reduce the apoptotic and inflammatory responses of renal TEC, alleviating AKI by mitigating the transcriptional inhibition of SOX9 [ 34 ]. Furthermore, EZH2 inhibition was proven to suppress cisplatin-induced renal TEC apoptosis and AKI by maintaining the expression level of E-calmodulin [ 35 ].…”

The SOX4/EZH2/SLC7A11 signaling axis mediates ferroptosis in calcium oxalate crystal deposition-induced kidney injury.

“…Moreover, the protective effect of EZH2 inhibition with 3-DZNep have been demonstrated in kidney injuries. In a model of sepsis-induced AKI, inhibition of EZH2 expression could reduce the apoptotic and in ammatory responses of renal TEC, alleviating AKI by mitigating the transcriptional inhibition of SOX9 [33]. Furthermore, EZH2 inhibition was proven to suppress cisplatin-induced renal TEC apoptosis and AKI by maintaining the expression level of E-calmodulin [34].…”

Role of SPRY4 in health and disease

“…Consistent with previous results, researchers found that overexpression of SPRY4 induces apoptosis in human colorectal cancer cell lines (SW480), increasing the apoptotic rate, upregulating the expression of pro-apoptotic proteins (Bax, Cleaved Caspase-3), and downregulating the expression of anti-apoptotic proteins (Bcl2 and EZH2) ( 8 ). It has been reported that silencing EZH2 can reduce apoptosis and inflammatory responses in renal tubular epithelial cells ( 39 ). Therefore, it is speculated that SPRY4 may induce apoptosis by inhibiting EZH2.…”