DNMT1-mediated DNA methylation in toll-like receptor 4 (TLR4) inactivates NF-κB signal pathway-triggered pyroptotic cell death and cellular inflammation to ameliorate lipopolysaccharides (LPS)-induced osteomyelitis

• DOI: 10.1016/j.mcp.2023.101922
• Publication Date: 2023-07-31T17:01:06Z
• Authors: Muguo Song; Junyi Li; Jian Sun; Xiaoyong Yang; Xijiao Zhang; Kehan Lv; Yongqing Xu; Jian Shi
• Keywords: Chromatin immunoprecipitation; DNMT1

Toll-like receptor 4 (TLR4) plays a critical role in various human diseases, and was associated with pyroptotic cell death inflammatory responses. DNA methylation, which has stable reversible properties, been reported to alter the expression of target genes, including TLR4. However, methylated TLR4 osteomyelitis (OM) underlying molecular mechanisms remain unclear. RNA sequencing used identify differentially expressed genes signaling pathways. RT-qPCR, Western blot, emzyme-linked immunosorbent assay (ELISA), counting kit-8 (CCK-8) LDH kit were detect mRNA protein relevant viability activity, respectively. methylation detected by methylation-specific PCR (MSP) verified Chromatin immunoprecipitation (ChIP). Here, we found that methyltransferase-1 (DNMT1)-mediated demethylation significantly suppressed lipopolysaccharides (LPS)-induced pyroptosis response inhibiting TLR4/nuclear transcription factor-kappa B (NF-κB) axis. First, confirmed as study transcriptome analysis, observably high-expressed both OM patients LPS-treated osteoblastic MC3T3-E1. Then, downregulation DNMT1 blocked promoter modification, resulting upregulation Simultaneously, functional experiments indicated suppression or overexpression promoted proliferation inhibited inflammation LPS-induced MC3T3-E1, while restored effects silencing on progression. In addition, elevated phosphorylation IκB-α NF-κB p65 signal pathway, inhibition inhibitor PDTC reversed influence DNMT1. conclusion, our demonstrated DNMT1-mediated alleviated pathway.