Interference of Interleukin-1 Mediated by Lentivirus Promotes Functional Recovery of Spinal Cord Contusion Injury in Rats via the PI3K/AKT1 Signaling Pathway.

Purpose: Inflammation and apoptosis after spinal cord contusion (SCC) are important causes of irreversible spinal cord injury. Interleukin-1 (IL-1) is a key inflammatory factor that promotes the aggravation of spinal cord contusion. However, the specific role and regulatory mechanism of IL-1 in spinal cord contusion is still unclear. Therefore, this study applied bioinformatics to analyze and mine potential gene targets interlinked with IL-1, animal experiments and lentiviral interference technology were used to explore whether IL-1 affected the recovery of motor function in spinal cord contusion by interfering with PI3K/AKT1 signaling pathway.

Method: This study used bioinformatics to screen and analyze gene targets related to IL-1. The rat SCC animal model was established by the Allen method, and the Basso Beattie Bresnahan (BBB) score was used to evaluate the motor function of the spinal cord-injured rats. Immunohistochemistry and immunofluorescence were used to localize the expression of IL-1 and AKT1 proteins in spinal cord tissue. Quantitative polymerase chain reaction and Western blot were used to detect the gene and protein expressions of IL-1, PI3K, and AKT1. RNAi technology was used to construct lentivirus to inhibit the expression of IL-1, lentiviral interference with IL-1 was used to investigate the effect of IL-1 and AKT1 on the function of spinal cord contusion and the relationship among IL-1, AKT1, and downstream signaling pathways.

Results: Bioinformatics analysis suggested a close relationship between IL-1 and AKT1. Animal experiments have confirmed that IL-1 is closely related to the functional recovery of spinal cord contusion. Firstly, from the phenomenological level, the BBB score decreased after SCC, IL-1 and AKT1 were located in the cytoplasm of neurons in the anterior horn of the spinal cord, and the expression levels of IL-1 gene and protein in the experimental group were higher than those in the sham operation group. At the same time, the expression of AKT1 gene decreased, the results suggested that the increase of IL-1 affected the functional recovery of spinal cord contusion. Secondly, from the functional level, after inhibiting the expression of IL-1 with a lentivirus-mediated method, the BBB score was significantly increased, and the motor function of the spinal cord was improved. Thirdly, from the mechanistic level, bioinformatics analysis revealed the relationship between IL-1 and AKT1. In addition, the experiment further verified that in the PI3K/AKT1 signaling pathway, inhibition of IL-1 expression upregulated AKT1 gene expression, but PI3K expression was unchanged.

Conclusion: Inhibition of IL-1 promotes recovery of motor function after spinal cord injury in rats through upregulation of AKT1 expression in the PI3K/AKT1 signaling pathway. Bioinformatics analysis suggested that IL-1 may affect apoptosis and regeneration by inhibiting the expression of AKT1 in the PI3K/AKT1 signaling pathway to regulate the downstream FOXO, mTOR, and GSK3 signaling pathways; thereby hindering the recovery of motor function in rats after spinal cord contusion. It provided a new perspective for clinical treatment of spinal cord contusion in the future.