Bae Won-Jung, Lee Sang-Im
Department of Pharmacology, College of Dentistry, Dankook University, Cheonan 31116, Republic of Korea.
Department of Dental Hygiene, College of Health Science, Dankook University, Cheonan 31116, Republic of Korea.
Int J Mol Sci. 2025 May 21;26(10):4959. doi: 10.3390/ijms26104959.
Oral cellular aging plays a critical role in the pathogenesis of chronic periodontitis and alveolar bone resorption. Although activating transcription factor 3 (ATF3) has been implicated as a senescence-associated factor, its specific role in periodontal ligament cell (PDLC) senescence remains unclear. Human PDLCs were exposed to lipopolysaccharide (LPS, 1 μg/mL) and nicotine (5 mM) for 3 days to induce senescence. ATF3 expression was silenced using siRNA. The expression of senescence-associated secretory phenotype (SASP) factors (IFNγ, IL6, IL8, TNFα, and IL1β) and the secretion of nitric oxide (NO) and prostaglandin E (PGE) were assessed by RT-PCR and immunoassay. Conditioned media (CM) from these cells were applied to mouse bone marrow macrophages (BMMs) to evaluate osteoclast differentiation and bone resorption. In addition, key signaling pathways, including STAT3, ERK, NF-κB (p65), and AP-1, were investigated by Western blotting and immunofluorescence. ATF3 knockdown markedly reduced the LPS/nicotine-induced expression of SASP factors and decreased NO and PGE levels. CM from ATF3-silenced PDLCs markedly inhibited osteoclast differentiation, as evidenced by reduced tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells and diminished bone resorption. Moreover, ATF3 inhibition led to a decreased RANKL/OPG ratio and attenuated the phosphorylation of STAT3 and ERK, along with the reduced nuclear translocation of p65 and AP-1 components. These findings suggest that ATF3 plays a critical role in mediating cellular senescence and osteoclastogenesis in PDLCs. Targeting ATF3 may represent a novel therapeutic strategy for managing age-related oral diseases, such as chronic periodontitis.
口腔细胞衰老在慢性牙周炎和牙槽骨吸收的发病机制中起关键作用。尽管激活转录因子3（ATF3）被认为是一种衰老相关因子，但其在牙周膜细胞（PDLC）衰老中的具体作用仍不清楚。将人PDLC暴露于脂多糖（LPS，1μg/mL）和尼古丁（5mM）中3天以诱导衰老。使用小干扰RNA使ATF3表达沉默。通过逆转录聚合酶链反应（RT-PCR）和免疫测定评估衰老相关分泌表型（SASP）因子（IFNγ、IL6、IL8、TNFα和IL1β）的表达以及一氧化氮（NO）和前列腺素E（PGE）的分泌。将这些细胞的条件培养基（CM）应用于小鼠骨髓巨噬细胞（BMM）以评估破骨细胞分化和骨吸收。此外，通过蛋白质免疫印迹法和免疫荧光研究包括信号转导和转录激活因子3（STAT3）、细胞外信号调节激酶（ERK）、核因子κB（p65）和活化蛋白-1（AP-1）在内的关键信号通路。ATF3基因敲低显著降低LPS/尼古丁诱导的SASP因子表达，并降低NO和PGE水平。来自ATF3沉默的PDLC的CM显著抑制破骨细胞分化，这通过抗酒石酸酸性磷酸酶（TRAP）阳性多核细胞减少和骨吸收减少得到证明。此外，ATF3抑制导致核因子κB受体活化因子配体（RANKL）/骨保护素（OPG）比值降低，并减弱STAT3和ERK的磷酸化，同时p65和AP-1成分的核转位减少。这些发现表明，ATF3在介导PDLC细胞衰老和成骨细胞生成中起关键作用。靶向ATF3可能代表一种治疗与年龄相关的口腔疾病（如慢性牙周炎）的新策略。
