Objective To study the effect of overexpression of LncRNA TERC on the expression of histone H3K27 trimethylation (H3K27me3) and DKK1 after dexamethasone intervention in osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) to further validate its role in osteogenic differentiation.Methods ① Dexamethasone intervention in osteogenic differentiation of BMSCs. The experiment was divided into the control group (osteogenic induction alone) and the intervention group (Dexamethasone). On the 14th day, using alizarin red staining to detect the osteogenic differentiation ability, RT-PCR detection was performed on the 3rd, 7th, 14th, and 21st day of each group of cells in the expression of osteogenic-related genes, such as BMP-2, SMAD-1, Dlx5 and Dlx3. ② Dexamethasone intervened in the osteogenic differentiation of BMSCs; a TERC overexpression vector was constructed; and the following groups were set up: a blank control group (osteogenic group with Dexamethasone intervention); a blank vector group; and a TERC overexpression group. RT-PCR was performed to detect the expression of osteogenic genes, such as BMP-2, SMAD-1, Dlx5 and Dlx3, in the cells of each group on day 3, 7, 14 and 21, and Western blot was performed to detect the protein levels of H3K27me3 and DKK1 in the cells of each group. A Western blot assay was performed to detect the protein levels of H3K27me3 and DKK1 in each group of cells.Results ① After Dexamethasone intervened in the osteogenic differentiation of BMSCs, alizarin red staining showed a decrease in osteogenic capacity (all P<0.05), and RT-PCR showed that osteogenesis-related genes, such as BMP-2, SMAD-1, Dlx5 and Dlx3, were down-regulated with the prolongation of intervention time (all P<0.05). ② In the TERC overexpression transfection experiment, osteogenesis-related genes such as BMP-2, SMAD-1, Dlx5, Dlx3, etc. were up-regulated in the cells of the TERC overexpression group compared with those of the other two groups (P<0.05), and there was no difference in the expression levels of the osteogenic genes in the other two groups (P>0.05); the protein expression level of H3K27me3 in the cells of the TERC overexpression group was significantly increased compared with the other two groups (P both <0.05), and the protein level of DKK1 was significantly decreased compared with the other two groups (P both <0.05). The protein expression levels of the above genes in the other two groups were similar, with no significant difference (P>0.05).Conclusion Overexpression of LncRNA TERC significantly increased the ability of dexamethasone to interfere with BMSCs differentiation into osteoblasts, and was correlated with H3K27me3 and DKK1 in the intervention of dexamethasone in BMSCs differentiation into osteoblasts. |