Key genes and regulatory networks of hypoxic preconditioning on osteoblasts

Abstract

The purpose of this study was to identify the key genes and pathways involved in hypoxic preconditioning of osteoblasts. Cells of the hypoxic-preconditioning group underwent 10 min of hypoxic cultivation/10 min normoxic cultivation three times before 4 h of hypoxic cultivation. The long-time hypoxia group underwent 4 h of hypoxic cultivation, and the control group cells underwent 4 h of normoxic cultivation. Differences in miRNAs expressed were analyzed by high-throughput sequencing. MiRwalk 3.0 was used to predict the target genes and conduct a Gene Set Enrichment Analysis. The STRING database and Cytoscape were used to explore the hub genes. A total of 8635 genes and 121 pathways are enriched in the hypoxic-preconditioning compared with the long-time hypoxia group, including the hub genes Utp6, Eif3a, Etf1, Rrp12 and Mkks. 8,476 target genes and 121 pathways are enriched in the hypoxic-preconditioning group compared with the control group, including the hub genes Chd7, Cebpa and Fosb, and 9,315 target genes and 131 pathways are enriched in the long-term hypoxia group compared with the control group, including the hub genes Dcun1d2, Ube2d1 and Frk. Hypoxia preconditioning improved cell viability (p < 0.01), enhanced ALP, IL10 and VEGF expression, and inhibited IL6 expression (p < 0.05). Hypoxic preconditioning is an effective method for promoting osteoblast activity.

Keywords

• hypoxic preconditioning
• osteoblasts
• regulatory network
• hub genes