The protective role of the miR-25-mediated notch signaling pathway in the memory capacity and brain tissue of mice with central nervous system infections

Objective: The study aimed to explore the role of miR-25 and the Notch signaling pathway in the memory capacity and brain tissue of mice with central nervous system (CNS) infections.

Methods: A bioinformatics website and the dual-luciferase reporter assay were used to analyze the targeting relationship between miR-25 and Notch1. The mice were randomized into 7 groups (n=10 per group), including the normal group, the model group (lipopolysaccharide at a dose of 500 μg/kg for the model establishment), the NC group, the miR-25 mimic group, the miR-25 inhibitor group, the DAPT group, and the miR-25 inhibitor + DAPT group. qRT-PCR and western blot were used to measure the miR-25, Notch1, and Hes5 expression levels in the hippocampal CA1 region of the mice's brains, along with the cyclo-oxygenase 2 (COX-2) and inducible nitric oxide synthase (iNOS) levels in the mice's hippocampi.

Results: Compared with the normal mice, the model mice had up-regulated miR-25, COX-2, and iNOS expressions and down-regulated Notch1 and Hes5 expressions, lower superoxide dismutase (SOD) levels in the hippocampi, and higher malondialdehyde (MDA) levels. Compared with the model group, the miR-25 mimic and DAPT groups had down-regulated Notch1 and Hes5 expressions, lower learning and memory capacities and SOD levels, higher MDA levels, and up-regulated COX-2 and iNOS expressions.

Conclusion: Down-regulating miR-25 may improve the memory capacity in mice with CNS infections by activating the Notch signaling pathway.