RESUMEN
BACKGROUND: The involvement of micro RNAs (miRNAs) in multiple sclerosis (MS) has been recently explored. Up-regulated miRNAs may play critical roles in MS pathogenesis and may be used as a signature for MS. Besides, the role of inflammatory cytokines has been long established with recent focus on interleukin-17 (IL-17). OBJECTIVE: To evaluate the level of expression miR-18b in relation to IL-17A in relapsing remitting (RR) MS patients during relapse and remission SUBJECTS AND METHODS: Twenty-eight RRMS patients and 26 age and sex matched control subjects were included. Serum miR-18b was assessed by quantitative real-time PCR, and serum level of IL-17A was measured by ELISA. RESULTS: Serum miR-18b expression was higher in relapse compared with remission and with controls (24.8⯱â¯21.91 vs 2.49⯱â¯0.97 vs 1⯱â¯0.36 respectively; Pâ¯<â¯0.001). Serum IL-17Awas higher in MS patients during relapse than during remission and controls (8.49⯱â¯1.26â¯vs 5.78⯱â¯2.27â¯vs 4.18⯱â¯2.13, respectively; Pâ¯<â¯0.001). No correlations existed between miR-18 and IL-17 in MS patients during relapse (râ¯=â¯0.35; Pâ¯=â¯0.22) or remission (râ¯=â¯0.340; Pâ¯=â¯0.234). CONCLUSION: Upregulation of miR-18 during relapse in patients with RRMS points to a possible contribution to the pathogenesis of the inflammatory process in MS. The lack of a significant correlation between upregulated miR-18 and IL-17A implicates that the influence of miR-18 may be exhibited via another inflammatory pathway.