MicroRNA-150 Deletion Reduces the Occurrence and Severity of Rheumatoid Arthritis by Inhibiting IL-17.

Abstract

Background: Understanding the effects of epigenetic factors on the pathogenesis of rheumatoid arthritis (RA) is important for the early diagnosis and therapeutic intervention of this disease. MicroRNA-150 (miR-150) exerts an important influence on the development and function of lymphocytes. However, the role of miR-150 in the pathogenesis of RA remains unclear.

Objective: To explore the role of miR-150 in the pathogenesis of RA and the related immune mechanism.

Methods: In this study, we used miR-150 knock-out (miR-150KO) and created animal models of RA. Flow cytometry, immunohistochemistry, and real-time RT-PCR were employed to assess the frequency of T cell subsets and cytokines expression.

Results: Compared to wild-type (WT) mice, the onset of RA was postponed and the incidence of RA was reduced in miR-150KO mice. The expression of IL-4 and IFN-γ significantly increased while the expression of IL-17 decreased significantly in NKT and CD4+ T cells of KO mice compared to that of WT mice after RA induction. In addition, the expression of IL-4 and IFN-γ increased while the expression of IL-17 decreased significantly in the joint tissues of KO mice compared to that of WT mice. Furthermore, the mRNA expression of TNF-α and IL-17 decreased significantly in the synovial fluid cells of KO mice compared to that of the WT mice after RA induction.

Conclusion: MiR-150 deficiency decreases the expression of IL-17 in T cells and joint tissues, and alleviates the occurrence and progression of RA in mice.