Changes in N6‐methyladenosine RNA methylomes of human periodontal ligament cells in response to inflammatory conditions

Abstract

Objective To investigate the changes in the m6A methylation modification profile of human periodontal ligament cells (hPDLCs) in response to inflammatory conditions. Background Periodontitis is an infectious disease of the periodontal support tissue that leads to the loss of alveolar bone. HPDLCs are primary cells that can repair periodontal tissue defects caused by periodontitis. However, the inflammatory conditions induce inflammatory damage and decrease ossification of hPDLCs. This inflammatory response depends on genetic and epigenetic mechanisms, including m6A methylation. Methods HPDLCs were cultured with osteogenic induction medium (NC group), while TNF‐α (10 ng/mL) and IL‐1β (5 ng/mL) were added to simulate inflammatory conditions (Inflam group). Then RNA‐seq and MeRIP‐seq analyses were performed to identify m6A methylation modification in the transcriptome range of hPDLCs. Results The results showed that the osteogenic differentiation of hPDLCs was inhibited under inflammatory conditions. RNA‐seq analysis also revealed that the decreased genes in response to inflammatory conditions were primarily annotated in processes associated with ossification. Compared with the NC group, differentially m6A‐methylated genes were primarily enriched in histone modification processes. Among 145 histone modification genes, 25 genes have been reported to be involved in the regulation of osteogenic differentiation, and they include KAT6B, EP300, BMI1, and KDMs (KDM1A, KDM2A, KDM3A, KDM4B, and KDM5A). Conclusion This study demonstrated that the m6A landscape of hPDLCs was changed in response to inflammation. M6A methylation differences among histone modification genes may act on the osteogenic differentiation of hPDLCs.

Multiplexed LC‐MS/MS quantification of salivary RNA modifications in periodontitis

“…According to Zhang et al, the expression of most m6A regulators was altered when comparing periodontitis patients to healthy subjects, suggesting that the m6A regulators can be involved in the development of periodontitis 22 . In the same way, Sun et al and Zou et al found changes in m6A methylated genes in periodontal ligament cells during inflammatory phenomena associated with a decrease in osteogenic differentiation 23,24 . Thus, we hypothesized that epitranscriptomics profiling could be useful in the search for biomarkers of periodontal disease.…”

“…Among RNA modifications, methylation and especially m6A, is the most studied. M6A appears to have a major role in the osteogenic differentiation of periodontal ligament stem cells, 23,24 as well as in the immune microenvironment of periodontitis. 22 As methylations are dynamically regulated, m6A can also be further methylated in m6Am by the methyltransferase PCIF1.…”

“…22 In the same way, Sun et al and Zou et al found changes in m6A methylated genes in periodontal ligament cells during inflammatory phenomena associated with a decrease in osteogenic differentiation. 23,24 Thus, we hypothesized that epitranscriptomics profiling could be useful in the search for biomarkers of periodontal disease.…”

Sinensetin protects against periodontitis through binding to Bach1 enhancing its ubiquitination degradation and improving oxidative stress

“…Cell culture and inflammatory stimulation have been described as previous study. 40 PDLCs were cultured in DMEM containing 10% FBS and 1% penicillin/streptomycin. PDLCs between passages 2 and 5 were used for subsequent experiments.…”

Sinensetin protects against periodontitis via binding to Bach1, enhancing its ubiquitination degradation and improving oxidative stress

“…The PDLCs were purchased from ScienCell Research Laboratories (ScienCell, #2630). Cell culture and in ammatory stimulation have been described as previous study 39 . PDLCs were cultured in DMEM containing 10% FBS and 1% penicillin/streptomycin.…”