miR-183 inhibits microglia activation and expression of inflammatory factors in rats with cerebral ischemia reperfusion via NF-κB signaling pathway.

Ischemic stroke represents 87% of all strokes, and is the third leading cause of disability and mortality worldwide. The cause of ischemic stroke is the obstruction of blood flow through the artery that supplies oxygen-rich blood to the brain, with ischemia-reperfusion injury as its major cause. microRNAs (miRNA) are small non-coding RNAs, which serve important roles in the regulation of gene expression at the post-transcription level. The aim of the present study was to investigate the effect of miRNA-183 (miR-183) on microglia activation in rats with cerebral ischemia-reperfusion injury. To this end, a rat cerebral ischemia-reperfusion injury model was established. The results indicated that miR-183 expression was decreased by cerebral ischemia-reperfusion. In addition, treatment using miR-183 agomir significantly reduced the neurological function scores, percentage of cerebral infarction volume, and ionized calcium-binding adapter molecule-1 (IBA-1)-positive cells in the CA1 area of the hippocampus in rats subjected to cerebral ischemia-reperfusion injury, implicating a neuroprotective role for miR-183. MiR-183 agomir treatment also decreased the expression of pro-inflammatory-associated proteins interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α. Finally, the expression of the nuclear factor (NF)-κB p65 and IκBα was decreased and increased by miR-183 agomir treatment, respectively, indicating inhibition of the NF-κB signaling pathway. These observations suggest that miR-183 regulates the activation of microglia in rats with cerebral ischemia-reperfusion injury by inhibiting the NF-κB signaling pathway.