Functional effects of microRNA-211-5p-targeted inhibition of erythropoietin hepatocyte kinase receptor and ligand B2 signaling pathway on spinal cord nerve injury
10.3760/cma.j.cn115455-20221116-00992
- VernacularTitle:微小RNA-211-5p靶向抑制促红细胞生成素肝细胞激酶受体及配体B2信号通路对脊髓神经损伤和功能影响研究
- Author:
Mingwu LI
1
;
Lihui QIAN
;
Farui SUN
;
Jun DUAN
;
Liang LIU
Author Information
1. 黄石市中心医院（湖北理工学院附属医院）骨科，黄石 435000
- Keywords:
Spinal cord injury;
MicroRNA-211-5p;
Erythropoietin producing hepatocyte kinase;
Function
- From:
Chinese Journal of Postgraduates of Medicine
2024;47(3):212-221
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To detect the expression of microRNA (miR)-211-5p, erythropoietin hepatocyte kinase receptor B2 (EphB2) and erythropoietin hepatocyte kinase ligand B2 (ephrin B2) in spinal cord tissues as well as nerve cells after spinal cord injury (SCI), and to explore their mechanisms and effects on neurological recovery in SCI rats.Methods:The study was conducted from May 2020 to June 2021 using Sprague Dawley (SD) rats and PC12 cells. SD rats were divided into sham-operated group and SCI group of 30 rats each, and Basso-Beattie-Bresnahan (BBB) score were performed at different postoperative time points (1, 3, 7, 14, 21 and 28 d), and the relative expression of miR-211-5p and Eph/ephrin B2 mRNA was measured by quantitative real-time polymerase chain reaction (qPCR); the SCI rats were divided into recombinant lentiviral vector LV-miR-211-5p group (group A), empty lentiviral vector LV-eGFP (group B) and saline group (group C), with 15 rats in each group, respectively. The recombinant lentiviral vector, empty lentiviral vector and saline were injected on the cephalic and caudal sides of the spinal cord injury, and the relative expression of miR-211-5p and Eph/ephrin B2 mRNA in the spinal cord tissue was measured at 1, 7 and 14 d after surgery. In addition, a PC12 injury cell line model was established with 150 μmol/L hydrogen peroxide (H 2O 2), and the apoptosis rate and apoptosis-related proteins and contents of different cell lines were detected by flow cytometry and Western blot, respectively. MiR-211-5p was verified to target EphB2 by dual luciferase reporter gene. Results:The results of the animal experiments showed that at different postoperative time points, the miR-211-5p levels in the SCI group were lower than those in the SHAM group: 0.70 ± 0.03 vs. 1.00 ± 0.10, 0.60 ± 0.04 vs. 1.00 ± 0.05, 0.45 ± 0.10 vs. 1.00 ± 0.12, 0.30 ± 0.06 vs. 1.00 ± 0.15, 0.20 ± 0.05 vs. 1.00 ± 0.13, 0.10 ± 0.02 vs. 1.00 ± 0.07. In contrast, levels of Eph/ephrin B2 were higher in the SCI group compared to the SHAM group: 1.10 ± 0.05 vs. 1.00 ± 0.01, 1.80 ± 0.01 vs. 1.00 ± 0.08, 2.30 ± 0.01 vs. 1.00 ± 0.10, 2.60 ± 0.01 vs. 1.00 ± 0.05, 2.80 ± 0.01 vs. 1.00 ± 0.06, 3.00 ± 0.01 vs. 1.00 ± 0.07 and 1.20 ± 0.05 vs. 1.00 ± 0.02, 1.60 ± 0.01 vs. 1.00 ± 0.03, 2.10 ± 0.10 vs. 1.00 ± 0.01, 2.40 ± 0.11 vs. 1.00 ± 0.09, 2.70 ± 0.13 vs. 1.00 ± 0.05, 2.90 ± 0.12 vs. 1.00 ± 0.03 ( P<0.05). At 14 d after surgery, Group A exhibited higher BBB scores than Groups B and C: (14.0 ± 1.1) points vs. (8.0 ± 1.1) and (8.2 ± 1.2) points, while miR-211-5p levels were higher than those in Groups B and C: 1.90 ± 0.10 vs. 0.40 ± 0.01 and 0.50 ± 0.02, and Eph/ephrin B2 levels were lower than those in Groups B and C: 0.70 ± 0.10 vs. 1.80 ± 0.04 and 1.90 ± 0.06, 0.60 ± 0.03 vs. 2.00 ± 0.04 and 2.10 ± 0.05 ( P<0.05). Immunofluorescence staining showed that the levels of GAP-43 and synaptophysin in group A were higher than those in groups B and C at 14 d after surgery ( P<0.05). Cellular assays showed that overexpression of miR-211-5p inhibited the apoptosis rate of H 2O 2-induced PC12 cells and the expression of the apoptosis-related gene Cleaved-caspase3 ( P<0.05). Knockdown of miR-211-5p increased the apoptosis rate of H 2O 2-induced PC12 cells and the expression of the apoptosis-related gene Cleaved-caspase3 ( P<0.05). Dual luciferase reporter gene assay confirmed that EphB2 was a target gene of miR-211-5p and overexpression of EphB2 antagonized the inhibitory apoptosis effect of miR-211-5p on H 2O 2-induced PC12 cells. Conclusions:This study showed that miR-211-5p could promote neurological repair in SCI by inhibiting the expression of Eph/ephrin B2 signaling pathway, suggesting that using miR-211-5p as a target to inhibit Eph/ephrin B2 signaling pathway may have a protective effect on SCI.
