McKay, Kelsea2022-02-282022-02-282022-02-28http://hdl.handle.net/10393/43333http://dx.doi.org/10.20381/ruor-27550Multiple Sclerosis (MS) is a chronic, inflammatory disease of the central nervous system. MS is caused by the immune-mediated destruction of myelin and oligodendrocytes, resulting in demyelination and neurodegeneration. The microRNA miR-145-5p has been demonstrated to be upregulated in MS lesions. Our lab has previously shown that dysregulation of miR-145-5p can interfere with oligodendrocyte differentiation in mice and that knockout of miR-145-5p protects mice from experimental autoimmune encephalomyelitis (EAE), a model for MS. The objective of this study is to determine if inhibition of miR-145-5p with an antisense oligonucleotide (ASO) is sufficient to protect mice from EAE. Female mice were induced with EAE and then treated with a control or miR-145 ASO at the onset of disease. We evaluated disease progression by monitoring clinical severity, and evaluating molecular and structural characteristics of EAE by RT-qPCR, histology, immunohistochemistry and electron microscopy. We have shown that the miR-145 ASO reduced miR-145-5p expression in the lumbar spinal cord, spleen and thymus following EAE induction. Treatment with the miR-145-5p ASO resulted in improved clinical severity of EAE, reduced neuroinflammation and increased myelination. Inhibition of miR-145-5p may represent a novel treatment for MS.enMultiple SclerosisExperimental Autoimmune EncephalomyelitisRemyelinationmicroRNAsAntisense OligonucleotideOligodendrocyteThesis