Mirna expression profiling of osteogenic differentiation of bone marrow mesenchymal stem cells induced by microchannel porous hydroxyapatite scaffold / 中国组织工程研究

ABSTRACT

BACKGROUND: Porous hydroxyapatite scaffolds have good osteogenesis in vivo and in vitro. However, little research has been done on the complex regulation mechanisms of miRNAs involved. OBJECTIVE: To investigate the changes of related miRNA expression in rat bone marrow mesenchymal stem cells during osteogenic mineralization by porous hydroxyapatite scaffolds. METHODS: Rat bone marrow mesenchymal stem cells were isolated, cultured and identified in vitro. Bone marrow mesenchymal stem cells co-cultured with porous hydroxyapatite scaffold were as experimental group, and bone marrow mesenchymal stem cells cultured alone served as blank control group, both of which underwent osteogenic induction for 7 days. During the osteogenic mineralization, miRNA high-throughput sequencing technology was used to analyze the changes of miRNA expression profiles followed by GO analysis. The miRNA molecules with obvious expression differences were screened and verified by qRT-PCR. RESULTS AND CONCLUSION: (1) Compared with the blank control group, in the experimental group, the expression levels of BMP2, ALP and Runx2 mRNA were up-regulated, and the expression level of BMP2 was up-regulated significantly (P < 0.05). (2) Results of miRNA high-throughput sequencing showed that 13 miRNAs such as miR-210-3p and miR-146a-5p were up-regulated, and 17 miRNAs such as let-7c-3p and let-3615 were down-regulated significantly. (3) GO analysis revealed that up-regulated miRNA target genes were mainly involved in biological regulation, cellular gene expression, and gene expression regulation, mainly including nuclear factor-κB, Toll-like receptor 9, intercellular adhesion, interleukin-1 regulation, and signaling pathways such as angiogenesis and Hippo. (4) Real-time fluorescence quantitative qPCR results showed that miRNA-210 was up-regulated 15 times and miR-146a-5p was up-regulated 10 times in the experimental group (P < 0.05). These results indicate that the new microchannel porous hydroxyapatite scaffold can promote the differentiation of bone marrow mesenchymal stem cells by up-regulating miRNA-210-3p and miR-146a.