Lactylation Of Preosteoclast Regulates The Healing Of Mandible Defects.

The aim of this study was to investigate the presence of lactylation in preosteoclasts under hypoxic microenvironment conditions. Furthermore, the study sought to examine the impact of lactylation on the coupling of osteoclast-type H vessel in mandibular bone defect healing, with the ultimate goal of enhancing mandibular bone repair through regulation of this process. In this study, eight-week-old male C57BL/6 mice were used to establish mandibular defect models. The changes of preosteoclast and osteoclast-type h vessel coupling during bone healing were evaluated by immunofluorescence staining and TRAP staining. Meanwhile, RAW264.7 cells were induced to preosteoclast under hypoxic conditions in vitro, and lactylation proteomics sequencing was performed, followed by relevant bioinformatics analysis. In addition, the conditioned medium of preosteoclast was co-cultured with HUVECs to evaluate the effects on angiogenesis. In vivo studies have shown that in a hypoxic microenvironment, the proliferation and differentiation ability of preosteoclast are enhanced, which is closely related to the formation of type H vessels. In addition, it also have demonstrated that the lactylation level of preosteoclast increases under hypoxic conditions, and proteomic analysis indicates that HSP90 may be one of the important targets of major lactylation. Moreover, co-culture results suggest that preosteoclast can promote the formation of vessels in vitro under hypoxic microenvironments. This study has discovered that preosteoclast undergo lactylation in the early stage of bone repair. This process may be closely related to the formation of type H vessels and the healing of bone defects.