MiR-24 inhibits oligodendrocyte precursor cell differentiation after spinal injury by targeting adrenal medulla.

OBJECTIVE: Oligodendrocyte precursor cells (OPCs) differentiate into oligodendrocytes (OLs) that provide nutrients to neurons. Adrenal medulla is (ADM) involved in nerve damage. MiR-24 participates in various diseases. However, the regulation and mechanism of miR-24 in oligodendrocyte precursor cell differentiation after spinal injury is unclear. MATERIALS  AND METHODS: Wistar rats were divided into sham operation group and model group. Real Time-PCR detects miR-24, PDGFRa and NG2 and MBP expression. OPC cells were cultured and divided into control group, miR-24 group, and si-miR-24 group followed by analysis of miR-24 expression by Real Time-PCR, expression of PDGFRa, NG2 and MBP by Western blot, as well as ADM content and secretion of IL-6 and TNF-α by enzyme-linked immunosorbent assay (ELISA). RESULTS: Expression of miR-24, PDGFRa, and NG2 was increased in the model group and MBP and ADM expression was decreased with increased secretion of IL-6 and TNF-α. Compared with control group, the difference was statistically significant (p<0.05). Upregulation of miR-24 promoted the expression of PDGFRa and NG2, decreased MBP and ADM level, and increased IL-6 and TNF-α secretion. Compared with control group, the difference was statistically significant (p<0.05). Downregulation of miR-24 reversed the above changes, and the difference was statistically significant (p<0.05). CONCLUSIONS: MiR-24 expression is increased in spinal injury. Upregulation of miR-24 expression reduces adrenal medulla expression and inhibits oligodendrocyte precursor cell differentiation.