SETD1 and NF-κB Regulate Periodontal Inflammation through H3K4 Trimethylation

Abstract

The inflammatory response to periodontal pathogens is dynamically controlled by the chromatin state on inflammatory gene promoters. In the present study, we have focused on the effect of the methyltransferase SETD1B on histone H3 lysine K4 (H3K4) histone trimethylation on inflammatory gene promoters. Experiments were based on 3 model systems: 1) an in vitro periodontal ligament (PDL) cell culture model for the study of SETD1 function as it relates to histone methylation and inflammatory gene expression using Porphyromonas gingivalis lipopolysaccharide (LPS) as a pathogen, 2) a subcutaneous implantation model to determine the relationship between SETD1 and nuclear factor κB (NF-κB) through its activation inhibitor BOT-64, and 3) a mouse periodontitis model to test whether the NF-κB activation inhibitor BOT-64 reverses the inflammatory tissue destruction associated with periodontal disease. In our PDL progenitor cell culture model, P. gingivalis LPS increased H3K4me3 histone methylation on IL-1β, IL-6, and MMP2 gene promoters, while SETD1B inhibition decreased H3K4me3 enrichment and inflammatory gene expression in LPS-treated PDL cells. LPS also increased SETD1 nuclear localization in a p65-dependent fashion and the nuclear translocation of p65 as mediated through SETD1, suggestive of a synergistic effect between SETD1 and p65 in the modulation of inflammation. Confirming the role of SETD1 in p65-mediated periodontal inflammation, BOT-64 reduced the number of SETD1-positive cells in inflamed periodontal tissues, restored periodontal tissue integrity, and enhanced osteogenesis in a periodontal inflammation model in vivo. Together, these results have established the histone lysine methyltransferase SETD1 as a key factor in the opening of the chromatin on inflammatory gene promoters through histone H3K4 trimethylation. Our studies also confirmed the role of BOT-64 as a potent molecular therapeutic for the restoration of periodontal health through the inhibition of NF-κB activity and the amelioration of SETD1-induced chromatin relaxation.

Downregulation of Macrophage-Specific Act-1 Intensifies Periodontitis and Alveolar Bone Loss Possibly via TNF/NF-κB Signaling

“…These results further confirm the role of macrophage-specific Act-1 on periodontitis via immune modulation, inflammation regulation, and immune cell migration. NF-κB regulates periodontal inflammation and the pathophysiology of periodontitis (Francis et al, 2020). TNF/NF-κB signaling also plays a role in the pathophysiology of various inflammatory diseases (Liedtke and Trautwein, 2012;Kunz, 2013;Sayegh et al, 2019).…”

“…NF-κB regulates periodontal inflammation and the pathophysiology of periodontitis ( Francis et al, 2020 ). TNF/NF-κB signaling also plays a role in the pathophysiology of various inflammatory diseases ( Liedtke and Trautwein, 2012 ; Kunz, 2013 ; Sayegh et al, 2019 ).…”

Epigenetic regulation of inflammation in periodontitis: cellular mechanisms and therapeutic potential

“…Accumulating evidence indicates that oral pathogens can induce rapid changes in histone methylation also in other cell types. LPS stimulation of PDL cells leads to the accumulation of the activating H3K4Me3 marks and reduction of repressive H3K27 trimethylation on inflammatory gene promoters [ 38 , 39 ]. Histone demethylase JMJD3 (KDM6B), which catalyzes H3K27 demethylation, is recruited to IL6 and IL12B promoters and promotes gene transcription [ 38 ].…”

“…Histone demethylase JMJD3 (KDM6B), which catalyzes H3K27 demethylation, is recruited to IL6 and IL12B promoters and promotes gene transcription [ 38 ]. Similarly, the H3K4 methyltransferase SETD1B is upregulated in LPS-stimulated PDL cells and accumulates on the promoters of IL6 and IL1B genes [ 39 ]. Dynamic regulation of H3K27 as well as H3K4 trimethylation marks at the promoters of matrix-related and osteogenic genes ( COL1A1 , COL3A1 , and RUNX2 ) and other inflammatory mediators ( CCL5 , IL1B ) have also been observed in PDL cells following LPS stimulation [ 40 ].…”

“…The silencing of JMJD3 reduces LPS-induced IL-6, IL-8 and IL-12 production [ 38 ] and results in diminished alkaline phosphatase activity, indicative of reduced osteogenic potential [ 40 ]. SETD1B knockdown results in reduced IL6 and IL1B expression, associated with lower H3K4Me3 levels at IL6 and IL1B promoters [ 39 ]. It remains to be tested if pharmacological modulation of histone methylation regulators can recapitulate the effects of gene silencing and suppress pathological inflammatory processes in periodontitis.…”