Hypoxic preconditioning enhances cell hypoxia tolerance and correlated lncRNA and mRNA analysis

Hypoxia makes cells death but it is not always true. Short term anoxia can boost remaining cells activities and promote tissue repair. This study is to explore the effects of hypoxic preconditioning (HP) on osteoblasts and analyze the involved lncRNA and mRNA.

Human osteoblast was used. Normoxic control group (N) were cultured in normoxic culture medium (L-DMEM, 10% FBS and 1% penicillin-streptomycin) 8 h. Long-term hypoxic group (H) were cultured in 4 h hypoxic culture medium (200 μmol/L CoCl₂ and L-DMEM)/4 h normoxic culture medium. Hypoxic preconditioning group (HP) were received 3 times HP (cultured in 10 min hypoxic culture medium/10 min normoxic culture medium, which was HP 1times) and then cultured in 4 h hypoxic culture medium/4 h normoxic culture medium. Cell proliferation ability, osteonectin, transforming growth factor-β1, insulin like growth factors-1 and osteopontin were test. The lncRNA and mRNA was detected by high-throughput sequencing. p-Value < 0.05 was accepted as statistically significant.

Cell proliferation activity: N > HP > P. Corrected osteonectin, TGF-β1, IGF-1 and osteopontin: HP > P > N. High-throughput sequencing of gene shown the expression of 4630 RNAs. Further, we identified that HP group made 239 and 160 target genes up-regulated and down-regulated respectively compared with H group (p < 0.05). GO, KEGG and PPI analysis indicated relevant biological processes.

Hypoxic preconditioning alleviated cells anoxia tolerance and promoted cells to synthesis many cytokines. The protection mechanism involved many lncRNAs and mRNAs.