RESUMO
The aim of this study was to explore the role and pathological mechanism of microRNA-663b in interleukin-1beta (IL-1ß)-induced inflammation and apoptosis of nucleus pulposus cells. First, the best concentration and time to construct the nucleus pulposus cell inflammation model was screen out. Overexpression or inhibition of miR-663b expression was performed by adding microRNA-663b mimic or microRNA-663b inhibitor. 293T cells were transfected according to experimental requirements. The luciferase activity of each group was detected to analyze the targeted regulation of microRNA-663b on interleukin-1 receptor (IL1R1). Compared with the mimic negative control (NC) group, the expression of inflammatory factors in the microRNA-663b overexpression group was inhibited (P<0.05), and the expression of type 2 collagen and polysaccharide protein increased (P<0.05), and the apoptosis of nucleus pulposus cells was inhibited (P<0.01), and the number of TUNEL-positive cells decreased significantly (P<0.01), and the microRNA and protein expression of IL1R1, the ratio of P-P65/P65 and phospho-nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (P-IκBα)/nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) protein expression were significantly decreased (P<0.05). The expression of inflammatory factors in the miR-663b inhibitor group was significantly higher than that in the inhibitor NC group (P<0.01), and the expression of type 2 collagen and polysaccharide protein was significantly decreased (P<0.01), and the number of apoptosis cells and TUNEL staining positive cells increased (p<0.01). The expression of IL1R1 gene and protein was significantly increased (P<0.01). The ratio of P-P65/P65 and P-IκBα/IκBα protein expression increased (P<0.05). IL1R1 is a downstream target gene of microRNA-663b. MicroRNA-663b may down-regulate the expression of IL1R1 at the transcriptional level by targeting IL1R1, inhibit the inflammatory response of nucleus pulposus cells, and slow down the degeneration of nucleus pulposus cells.
