Over-expressed miR-27a-3p inhibits inflammatory response to spinal cord injury by decreasing TLR4.

We investigate whether microRNA-27a-3p (miR-27a-3p) can inhibit the inflammatory response of spinal cord injury by negatively regulating toll-like receptor 4 (TLR4).The quantitative Real-time polymerase chain reaction (qRT-PCR) assay was used to detect the expression of miR-27a-3p and TLR4 in serum samples from patients with spinal cord injury and in hydrogen peroxide-treated C8-B4 and C8-D1A cells. Dual luciferase reporter assays were used to detect targeted binding of TLR4 to miR-27a-3p. The protein expression of miR-27a-3p and TLR4 and the two inflammatory factors, tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6), were all detected by Western blot.TLR4 expression was elevated and miR-27a-3p was decreased in serum samples from patients with spinal cord injury and in hydrogen peroxide-treated C8-D1A and C8-B4 cells. Dual luciferase reporter assays results demonstrated that miR-27a-3p can bind to TLR4. Up-regulation of miR-27a-3p can decrease the expression of TNF-α and IL-6 and can also reduce TLR4 expression. After overexpression of TLR4, the expression of TNF-α and IL-6 were increased.miR-27a-3p can inhibit the inflammatory response of spinal cord injury by negatively regulating TLR4.