The presence of metal ions, such as titanium (Ti) ions, is toxic to adjacent tissues of implants. Indeed, Ti ions may induce an inflammatory response through the NF‐κB pathway, thus causing damage to soft and hard tissues. The involvement of Yes‐associated protein (YAP), a key factor of the Hippo pathway, in an immuno‐inflammatory response has been confirmed, whereas its role in Ti ion‐mediated inflammation has not been elucidated. Therefore, this study aimed to investigate the role of signal crosstalk between the Hippo/YAP and NF‐κB signaling pathways in the pro‐inflammatory effect of Ti ions on macrophages. In our work, RAW264.7 cells were cocultured with Ti ions. The migration capacity of macrophages under Ti ion exposure was measured by transwell assay. Western blot analysis was used to detect the expressions of related proteins. Polymerase chain reaction was used to evaluate the expression of pro‐inflammatory cytokines. The nucleus translocation of YAP and P65 was visualized and analyzed via immunofluorescence staining. The results showed that the migration of macrophages was promoted under Ti ion exposure. Ten parts per million Ti ions induced nuclear expression of YAP and activated the NF‐κB pathway, which finally upregulated the expression of pro‐inflammatory cytokines in macrophages. Moreover, the inhibition of the NF‐κB pathway rescued the reduction of YAP expression under Ti ion exposure. Most importantly, the overexpression of YAP exacerbated the inflammatory response mediated by Ti ions through the NF‐κB pathway. In summary, this study explored the mechanism of Hippo‐YAP/NF‐κB pathway crosstalk involved in the regulation of macrophage behaviors under Ti ion exposure.

中文翻译：

---

Hippo-YAP/NF-κB信号通路串扰在调节钛离子暴露下巨噬细胞生物学行为中的作用

金属离子，例如钛 (Ti) 离子的存在对植入物的邻近组织是有毒的。事实上，Ti 离子可能通过 NF-κB 通路诱导炎症反应，从而对软、硬组织造成损伤。已证实 Yes 相关蛋白 (YAP) 是 Hippo 通路的关键因素，参与免疫炎症反应，而其在 Ti 离子介导的炎症中的作用尚未阐明。因此，本研究旨在研究 Hippo/YAP 和 NF-κB 信号通路之间的信号串扰在 Ti 离子对巨噬细胞的促炎作用中的作用。在我们的工作中，RAW264.7 细胞与钛离子共培养。巨噬细胞在钛离子暴露下的迁移能力通过 transwell 测定法测量。Western印迹分析用于检测相关蛋白的表达。聚合酶链反应用于评估促炎细胞因子的表达。通过免疫荧光染色观察和分析 YAP 和 P65 的细胞核易位。结果表明，Ti离子暴露促进了巨噬细胞的迁移。百万分之十的钛离子诱导 YAP 的核表达并激活 NF-κB 通路，最终上调巨噬细胞中促炎细胞因子的表达。此外，NF-κB 通路的抑制挽救了钛离子暴露下 YAP 表达的减少。最重要的是，YAP 的过表达加剧了 Ti 离子通过 NF-κB 途径介导的炎症反应。总之，