Influence of titanium dioxide nanotubes on macrophage polarization and endothelial cell vascularisation under oxidative stress microenvironment

Elderly fracture healing is significantly impaired by oxidative stress-induced vascular dysfunction. This study investigates the effects of 110 nm titanium dioxide nanotubes (TNT 110 ) on macrophage polarization and endothelial cell vascularization under oxidative stress. Under H 2 O 2 -induced oxidative stress, RAW264.7 macrophages cultured on TNT 110 exhibit enhanced M1 polarization, with significantly upregulated M1 marker expression versus the Ti group. Conditioned medium from TNT 110 -stimulated macrophages markedly promoted HUVEC migration and tube formation by activating the ERK/Akt signaling pathway. In vivo, TNT 110 implants demonstrate superior neovascularization (CD31 + areas) and bone regeneration compared to pure titanium. These findings suggest that TNT 110 enhances vascular and bone tissue regeneration under oxidative stress by modulating macrophage polarization and endothelial cell signaling pathways. • TNT 110 induces slower polarization of macrophages towards M2 state under oxidative stress. • Crosstalk between HUVECs and macrophages enhances the migration function of HUVECs. • TNT 110 displays good vascular regeneration properties in vitro and in vivo under oxidative stress.