Su Qin, Chen Jiao
Department of Stomatology, Wuhan Fourth Hospital, Wuhan 430033, Hubei, P.R. China.
J Microbiol Biotechnol. 2025 Aug 18;35:e2505016. doi: 10.4014/jmb.2505.05016.
Periodontitis is a chronic inflammatory disease-causing tissue destruction and systemic effects. Despite significant advancements, the molecular mechanisms driving tissue degeneration remain incompletely understood. Emerging evidence suggests that RNA modifications, particularly N6-methyladenosine (mA) methylation, critically regulate inflammatory responses. This study investigates the role of METTL3-mediated mA modification of loricrin (LOR) in lipopolysaccharide (LPS)-induced periodontal injury. Bioinformatics analyses identified the key downregulated gene in periodontitis. To establish an periodontitis model, human periodontal ligament fibroblast (HPLF) cells were treated with LPS. LOR and METTL3 levels in clinical samples and HPLF cells were measured by qRT-PCR. Inflammatory cytokines, cell proliferation, and apoptosis were examined using ELISA, CCK8, EdU, and flow cytometry assays, respectively. The interaction between LOR and METTL3 was evaluated through Pearson correlation, MeRIP assay, qRT-PCR, immunoblotting, and mRNA stability assays. LOR was identified as a key downregulated gene in periodontitis, as validated in both clinical tissues and a periodontitis cell model. Functional assays showed that LPS-treatment promoted inflammatory cytokine production, inhibited cell proliferation, and increased apoptosis, whereas upregulating LOR in these cells reversed these effects. Furthermore, METTL3 expression was reduced in periodontitis clinical tissues and positively correlated with LOR expression. METTL3 overexpression enhanced LOR mRNA stability via mA methylation. Moreover, silencing METTL3 partially negated the protective effects of LOR overexpression in LPS-induced periodontitis cell model. These findings reveal that METTL3-mediated mA modification of LOR mitigates periodontal injury, suggesting that the METTL3-LOR axis may represent a potential avenue for future therapeutic exploration to maintain periodontal homeostasis.
牙周炎是一种导致组织破坏和全身影响的慢性炎症性疾病。尽管取得了重大进展，但驱动组织退化的分子机制仍未完全了解。新出现的证据表明，RNA修饰，特别是N6-甲基腺苷（m⁶A）甲基化，对炎症反应起着关键调节作用。本研究探讨了METTL3介导的loricrin（LOR）的m⁶A修饰在脂多糖（LPS）诱导的牙周损伤中的作用。生物信息学分析确定了牙周炎中关键的下调基因。为建立牙周炎模型，用人牙周膜成纤维细胞（HPLF）进行LPS处理。通过qRT-PCR检测临床样本和HPLF细胞中LOR和METTL3的水平。分别使用ELISA、CCK8、EdU和流式细胞术检测炎症细胞因子、细胞增殖和细胞凋亡。通过Pearson相关性分析、MeRIP分析、qRT-PCR、免疫印迹和mRNA稳定性分析评估LOR与METTL3之间的相互作用。LOR被确定为牙周炎中的关键下调基因，这在临床组织和牙周炎细胞模型中均得到验证。功能分析表明，LPS处理促进炎症细胞因子产生、抑制细胞增殖并增加细胞凋亡，而在这些细胞中上调LOR可逆转这些作用。此外，METTL3在牙周炎临床组织中的表达降低，且与LOR表达呈正相关。METTL3过表达通过m⁶A甲基化增强LOR mRNA稳定性。此外，沉默METTL3部分抵消了LOR过表达在LPS诱导的牙周炎细胞模型中的保护作用。这些发现揭示了METTL3介导的LOR的m⁶A修饰减轻了牙周损伤，表明METTL3-LOR轴可能代表了未来治疗探索以维持牙周稳态的潜在途径。
