O-GlcNAc Modification of CEBPB Promotes Astrocytic Pyroptosis by Activating NLRP3 Inflammasome Through Transcriptional Activation of IKKβ

Major depressive disorder (MDD) is associated with astrocytic pyroptosis, but the mechanisms involved remain unclear. This study investigates how O-GlcNAc modification of CCAAT enhancer binding protein beta (CEBPB) influences its ability to regulate pyroptosis in astrocytes. In our study, primary astrocytes were exposed to LPS plus ATP to activate NLRP3 inflammasomes. Cell viability was assessed by CCK8 assay. IL-18 and IL-1β release was measured using ELISA. sWGA pull-down and Co-IP assays were performed to assess O-GlcNAc modification level of CEBPB. ChIP assay was used for promoter binding analysis, and ubiquitination detection was performed using Co-IP. Our results showed that LPS+ATP treatment significantly increased IKKβ expression in astrocytes, and IKKβ knockdown markedly reduced NLRP3 inflammasome activity and pyroptosis. Mechanistically, CEBPB transcriptionally activated IKKβ expression in astrocytes. Functionally, CEBPB knockdown ameliorated LPS+ATP-induced NLRP3 inflammasome activation and pyroptosis in astrocytes, which was abolished by IKKβ overexpression. In addition, O-GlcNAc modification at Thr235 enhanced CEBPB protein stability in astrocytes, driving NLRP3 inflammasome activation and pyroptosis. Collectively, these findings demonstrated that O-GlcNAc-modified CEBPB promoted pyroptosis in astrocytes during MDD progression by activating NLRP3 inflammasome through transcriptionally activating IKKβ.