Apoevs Promote Diabetic Tooth Extraction Healing By Regulating Neutrophil Phenotype

To investigate the effect of apoptotic extracellular vesicles derived from stem cells from human exfoliated deciduous teeth (SHED-ApoEVs) on diabetic tooth extraction and its underlying mechanism of inducing neutrophil phenotypic transformation. C57BL6 mice (female, 6-8 w) were used to induce diabetes. SHED-ApoEVs were isolated and injected into the extraction socket of diabetic mice. The healing was observed by stereoscopic microscope, histological staining and micro-CT. The infiltration of pro-inflammatory neutrophils (N1) and anti-inflammatory neutrophils (N2) were observed by immunofluorescence staining. In vitro, neutrophils were co-cultured with SHED-ApoEVs. N1 and N2 were detected by flow cytometry and the cytokine expression were tested by ELISA. Proteomic analysis was used to further explore the mechanisms. The glycolysis level of neutrophils was measured be extracellular acidification rate (ECAR) and lactate production assay. The expression of HK2/PI3K/AKT was detected by western blot. SHED-ApoEVs promoted the gingiva and bone regeneration of tooth extraction, shortened the infiltration time and facilitated the N2 phenotypic transformation of neutrophils. After co-cultured with SHED-ApoEVs, the proportion of N1 decreased while N2 increased, accompanied by reduced pro-inflammatory cytokine and elevated anti-inflammatory cytokine expression. Moreover, ApoEVs promoted neutrophil phenotypic transformation by inhibiting the glycolytic rate-limiting enzyme HK2, thereby reducing ECAR and lactate production, which was related to the suppression of PI3K/AKT signaling pathway. SHED-ApoEVs promote the diabetic wound healing of tooth extraction through inhibiting PI3K/AKT pathway mediated glycolysis to induce neutrophil anti-inflammatory phenotypic transformation.