Role of lncRNA NONMMUT104330.1-miR-709-DDX58 axis in mediating immunomodulatory effects of enoxaparin sodium bone cement on macrophage polarization and inflammatory response.

BACKGROUND

PMMA bone cement is known to induce tissue inflammation around implants. A previous research group developed a novel material, enoxaparin sodium bone cement (ES-PMMA), which combines 40 g of PMMA bone cement with 8000 AxaIU of enoxaparin sodium. This innovative bone cement has demonstrated anti-inflammatory and immunomodulatory properties within the local tissue microenvironment. This study aimed to explore the underlying molecular mechanisms.

METHODS

RAW264.7 cells were treated with different bone cement extract mediums to observe macrophage polarization and the expression of inflammatory factors. RAW264.7 cells treated with different bone cement extract mediums were collected for lncRNA sequencing, and the sequencing results were analyzed using bioinformatics. The lncRNA NONMMUT104330.1-miR-709-DDX58 regulatory axis was constructed based on the competing endogenous RNA mechanism. Subsequently, lncRNA NONMMUT104330.1 in RAW264.7 cells was either knocked down or overexpressed to observe the inflammatory response of the cells.

RESULTS

ES-PMMA bone cement induces M2 polarization of macrophages and increases the expression of anti-inflammatory factors. A bioinformatics analysis was conducted on the sequencing results to construct the lncRNA NONMMUT104330.1-miR-709-DDX58 regulatory axis. A dual-luciferase reporter gene assay was employed to verify the binding feasibility of the axis, and the results demonstrated that miR-709 could bind to the molecular sites of lncRNA NONMMUT104330.1 and DDX58, respectively. Knockout and overexpression experiments of lncRNA NONMMUT104330.1 demonstrated that the knockdown of lncRNA NONMMUT104330.1 induced M2 polarization in RAW264.7 cells, leading to a reduction in pro-inflammatory factor expression and an increase in anti-inflammatory factor expression. Conversely, upon overexpression of lncRNA NONMMUT104330.1, RAW264.7 cells were polarized to M1, resulting in elevated levels of pro-inflammatory factors.

CONCLUSION

Enoxaparin sodium bone cement can induce M2 polarization of macrophages, thereby playing an anti-inflammatory immunomodulatory role. The lncRNA NONMMUT104330.1-miR-709-DDX58 axis may significantly contribute to this process.

CLINICAL TRIAL NUMBER

Not applicable.