miR-142 regulates the function of microvascular endothelial cells through MAT2B

Astrocytes play a critical role in maintaining the integrity of the blood-brain barrier (BBB) under physiological conditions and become activated and secrete certain inflammatory cytokines under inflammatory conditions. These inflammatory factors directly or indirectly exacerbate BBB disruption by regulating the expression of tight junction proteins (TJPs), which are located between brain capillary endothelial cells. It has been reported that the protective function of the BBB, which is fundamental for homeostasis and normal neuronal activity, could be altered during stress conditions. MiR-142 is one of the most abundant miRNAs in the brain and is considered a molecular link between inflammation and neuronal dysfunction. The present research focused on studying the impact of microRNA-142 (miR-142)-5p on the regulation between astrocytes and brain microvascular endothelial cells (BMVECs) under a simulated inflammatory condition. The results of the present study showed that the miR-142 inhibition could alleviate the disruption of BMVECs induced by lipopolysaccharide (LPS) induced astrocytic media (L-ACM) through upregulating the expression of tight junction proteins (TJPs), increasing the ratio of Bcl-2/Bax and downregulating the level of NF-κB. This effect of miR-142-5p inhibition might complement through binding to Methionine adenosyltransferase 2B (MAT2B). Taken together, the downregulation on the miR-142-5p level in BMVECs might be a promising therapeutic strategy for BBB damage in inflammatory condition.