Molecular Mechanism of TRIM16 Regulating Osteogenic Differentiation of Periodontal Ligament Stem Cells Under Inflammatory Microenvironment

ABSTRACT

This study explores the mechanism of TRIM16 on osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) in an inflammatory microenvironment. hPDLSCs were cultured and identified by flow cytometry and osteogenesis/adipogenesis induction. hPDLSCs were maintained with P. gingivalis LPS and induced by osteogenic differentiation. TRIM16, HOXA10, and KLF5 expression was tested via RT‐qPCR and Western blot. After overexpression of TRIM16, TNF‐α, IL‐6, and IL‐1β levels were examined via ELISA. Osteogenic differentiation of hPDLSCs was validated by Alizarin red staining, ALP staining, and Western blot. The binding of TRIM16 to HOXA10 was detected by Co‐IP, and the ubiquitinated HOXA10‐containing complexes were measured. Dual luciferase assay and ChIP analyzed the enrichment of HOXA10 on the KLF5 promoter. LPS treatment reduces TRIM16 and KLF5 expression, while elevating HOXA10 protein level. Overexpression of TRIM16 alleviates inflammation in LPS‐induced hPDLSCs and enhances osteogenic differentiation. Mechanistically, TRIM16 inhibits HOXA10 protein level via ubiquitination, thereby abating the enrichment of HOXA10 on the KLF5 promoter and promoting the expression of KLF5. In conclusion, TRIM16 facilitates osteogenic differentiation of hPDLSCs in an inflammatory microenvironment via HOXA10/KLF5 axis.