简介:AbstractBackground:Developing effective spinal cord repair strategies for spinal cord injury (SCI) is of great importance. Emerging evidence suggests that microRNAs (miRNAs) are closely linked to SCI recovery. This study aimed to investigate the function of miR-34c in the neuronal recovery in rats with SCI.Methods:A rat model with SCI was established. Differentially expressed miRNAs were identified by a microarray analysis. MiR-34c expression in rats was measured by reverse transcription quantitative polymerase chain reaction. Altered expression of miR-34c or C-X-C motif ligand 14 (CXCL14) was introduced in SCI rats to measure their roles in neuronal recovery. Western blot analysis was performed to determine the phosphorylation of Janus kinase 2 (JAK2) and signal transducer and activator of transcription-3 (STAT3). Neuronal apoptosis in rat spinal cord tissues was detected. The concentrations of SCI recovery-related proteins thyrotropin releasing hormone (TRH), prostacyclin (PGI2), and ganglioside (GM) were evaluated by enzyme-linked immunosorbent assay. Data were analyzed using a t-test with a one-way or two-way analysis of variance.Results:Rats with SCI presented decreased grip strength (112.03 ± 10.64 vs. 17.32 ± 1.49 g, P < 0.01), decreased miR-34c expression (7 days: 3.78 ± 0.44 vs. 0.95 ± 0.10, P < 0.05), and increased CXCL14 expression (7 days: 0.61 ± 0.06 vs. 2.91 ± 0.27, P < 0.01). MiR-34c was found to directly bind to CXCL14. Overexpression of miR-34c increased grip strength (11.23 ± 1.08 vs. 31.26 ± 2.99 g, P < 0.01) and reduced neuronal apoptosis in spinal cord tissues (53.61% ± 6.07% vs. 24.59% ± 3.32%, P < 0.01), and silencing of CXCL14 also increased the grip strength (12.76 ± 1.13 vs. 29.77 ± 2.75 g, P < 0.01) and reduced apoptosis in spinal cord tissues (55.74% ± 6.24% vs. 26.75% ± 2.84%, P < 0.01). In addition, miR-34c upregulation or CXCL14 downregulation increased the concentrations of TRH, PGI2, and GM, and reduced phosphorylation of JAK2 and STAT3 in rats with SCI (all P < 0.01).Conclusion:The study provided evidence that miR-34c could promote neuronal recovery in rats with SCI through inhibiting CXCL14 expression and inactivating the JAK2/STAT3 pathway. This study may offer new insights into SCI treatment.
简介:AbstractBackground:Myocardial infarction occurs due to insufficient (ischemia) blood supply to heart for long time; plasmacytoma variant translocation 1 (PVT1) is a long non-coding RNAs (lncRNAs) involved in the pathogenesis of various diseases, including heart disease; However, few studies have explored its role. The present study evaluated the effects of lncRNA PVT1 on hypoxic rat H9c2 cells.Methods:Hypoxic injury was examined by measuring cell viability and apoptosis by using cell counting kit-8 activity and flow cytometry assays. Gene expressions after hypoxia were estimated by quantitative real time polymerase chain reaction and the signaling pathway were explored by Western blot analysis. RNA immunoprecipitation and luciferase reporter assays were applied to examine the interactions among genes. Data were analyzed using t-test with one-way or two-way analysis of variance.Results:The lncRNA PVT1 is up-regulated in hypoxia-stressed H9c2 cells and knockdown of PVT1 mitigates hypoxia-induced injury in H9c2 cells. PVT1 acts as a sponge for miR-135a-5p and knockdown of PVT1 attenuated the increased hypoxia-induced injury by up-regulating miR-135a-5p. Forkhead box O1 (FOXO1) was identified as a target of miR-135a-5p, and the expression was negatively regulated by miR-135a-5p. The exploration of the underlying mechanism demonstrated that knockdown of FOXO1 reversed PVT1/miR-135a-5p mediated hypoxia-induced injury in H9c2 cells.Conclusions:PVT1 plays a crucial role in hypoxia-injured H9c2 cells through sponging miR-135a-5p and then positively regulating FOXO1.