Abstract: Demyelinating diseases of the central nervous system are common, yet few effective strategies for myelin repair and remyelination are available. An increasing number of studies highlight the role of microRNAs (miRNAs) as key regulators of demyelination. miRNA mimics and inhibitors, which are currently in preclinical development, have shown promise as novel therapeutic agents. However, the mechanisms by which they protect myelin are not fully understood. Using a mouse model of acute central nervous system demyelination induced by infection with Angiostrongylus cantonensis, we investigated alterations in miRNA expression in the mouse brain. Our findings revealed a significant early-stage increase in the levels of miR-200, particularly miR-200a and miR-200c. Subsequent analysis demonstrated that combined miR-200a and miR-200c overexpression improved neurobehavioral outcomes and attenuated demyelination in Angiostrongylus cantonensis-infected mice. Further lipid metabolomic profiling indicated that miR-200a and miR-200c synergistically inhibited the production of phosphatase and tensin homolog (PTEN) and activated the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway, as confirmed by double luciferase reporter assay and western blotting. Additionally, in vitro experiments showed that miR-200a and miR-200c protected oligodendrocyte precursor cells from lipopolysaccharide-induced damage and enhanced their survival. Our study indicates the critical role of miR-200a and miR-200c in protecting against central nervous system demyelination by targeting PTEN and modulating key survival pathways. Furthermore, our findings suggest that miR-200a and miR-200c are promising diagnostic biomarkers of and therapeutic targets for treating demyelination-related disorders.

Key words: Angiostrongylus cantonensis, central nervous system, demyelination, endogenous, miR-200s, phosphatase and tensin homolog