GLPK mediates inflammatory response in RAW264.7 macrophages through H3K23 succinylation-dependent mitochondrial homeostasis

LIU Yuxiang; MEI Jian; ZHU Xiangrui; OU Langlin; PANG Xiangming; MENG Zitong; TANG Yujing; SHEN Ao; WEN Shiqing; MA Cui

doi:10.13431/j.cnki.immunol.j.20240095

Abstract：Objective To elucidate the regulatory effects of Glycerol Kinase(GLPK)on the inflammatory response induced by lipopolysaccharide(LPS)in mouse Raw264.7 macrophages.Methods Raw264.7 macrophages were cultured in vitro,and an inflammatory model was established through LPS induction.The transcriptional levels of inflammatory cytokines NF-κB,TNF-α,IL-6,and IL-1β were quantified using RT-qPCR.The expression and localization of GLPK were examined via Western blot and immunofluorescence.Additionally,Western blot analysis was employed to detect the levels of cellular pan-succinylation and H3K23su expression.ChIP-qPCR was utilized to assess the enrichment of H3K23su modification at the IL-10 promoter.The total reactive oxygen species production was measured using DCFH-DA probes,while mitochondrial ROS levels were determined with Mito-SOX probes.Mitochondrial membrane potential changes,indicative of mitochondrial dysfunction,were evaluated using JC-1 fluorescent probes.Furthermore,GLPK overexpression plasmids were transfected into cells to investigate the effects of GLPK on inflammatory responses,mitochondrial function,and epigenetic modifications.Results LPS treatment led to mitochondrial dysfunction,inflammatory responses exacerbation,succinylation modifications reduction,and GLPK protein expression decrease in Raw264.7 cells.Overexpression of GLPK in LPS-treated cells improved mitochondrial function and reduced the transcription of pro-inflammatory cytokines.ChIP-qPCR analysis revealed that GLPK overexpression could reverse the LPS-induced suppression of H3K23su modification at the IL-10 promoter,thereby attenuating the inflammatory response.Conclusion LPS mediates inflammatory responses in Raw264.7 macrophages through a GLPK-dependent H3K23 succinylation modification mechanism.