MicroRNA expression aberration in Chinese patients with relapsing remitting multiple sclerosis.

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease that is caused by an abnormal immune system that attacks the central nervous system. MicroRNAs (miRNAs) are known to play essential roles in the immune system. Most of the previous studies about miRNA dysregulation in MS have focused on European populations. In the present study, the miRNA expression profiles associated with Chinese MS patients are investigated. Here, human miRNA expression profiling experiments were performed on the peripheral blood mononuclear leukocytes from ten MS patients and ten healthy controls. Nine overexpressed and six underexpressed miRNAs were found. The 15 miRNAs were validated independently in a second cohort of 40 MS patients and 40 controls by real-time PCR; six miRNAs were significantly abnormally expressed, and principal component analysis of six miRNAs indicated that the MS patients could be clearly differentiated from the healthy controls based on the miRNA expression patterns. This study provided the indications of abnormal miRNA expression patterns in the peripheral blood mononuclear leukocytes of Chinese MS patients. The potential roles of these differentially expressed miRNAs as MS biomarker and in pathogenesis need to be investigated in future studies.