[HO-1Cδ23 reduces the permeability of the blood-spinal barrier by upregulating miR-125a-5p after hypoxic injury].

Objective To detect the effects of microRNA 125a-5p (miR-125a-5p) in heme oxygenase 1 (HO-1) truncation (HO-1Cδ23) regulating the blood-spinal barrier (BSCB) after hypoxic injury. Methods HCMEC/D3 and astrocytes were co-cultured in Transwell chamber to establish BSCB model in vitro, and then prepared with cobalt chloride to establish BSCB hypoxic injury model. The experiment was divided into blank group, non-virus loading group, HO-1Cδ23 group (Lv-HO-1Cδ23), miRNA negative control group (Lv-HO-1Cδ23 combined with miR-NC treatment), miRNA mimic group (Lv-HO-1Cδ23 combined with miR-125a-5p mimics treatment) and miRNA inhibitor group (Lv-HO-1Cδ23 combined with miR-125a-5p inhibitor treatment). The expression levels of miR-125a-5p and zonula occludens-1 (ZO-1), occludin and vascular endothelial adhesion protein (VE-cadherin) were detected by reverse transcription PCR and real-time quantitative PCR. Western blot was used to detect the expressions of HO-1, ZO-1, occludin and VE-cadherin proteins. The permeability of BSCB in vitro was evaluated by the spillage rate of horseradish peroxidase (HRP). Results The success rate of HO-1Cδ23 transfection was about 70%. After transfection, the content of HO-1Cδ23 was significantly increased, and the expression of miR-125a-5p up-regulated compared with the blank group. Compared with the blank group, the mRNA and protein levels of ZO-1, occludin, and VE-cadherin in the HO-1Cδ23 group, the miRNA negative control group, and miRNA mimic group increased, but the HRP spillover rate decreased; on the contrary, the mRNA and protein levels of ZO-1 occludin and VE-cadherin in the miRNA inhibitor group decreased, while the HRP spillover rate increased significantly. Compared with the HO-1Cδ23 group, the mRNA and protein levels of ZO-1, occludin and VE-cadherin increased significantly in the miRNA mimic group, and the HRP spillover rate decreased significantly, while the mRNA and protein levels of ZO-1, occludin, and VE-cadherin as well as the HRP spillover rate in the miRNA inhibitor group showed the opposite trend. Conclusion Under hypoxic injury, HO-1Cδ23 may promote the transcription and translation of the genes involved in junction and adhesion and reduce the permeability of BSCB by up-regulating the expression of miR-125a-5p.