Abstract: ［Abstract］ Objective〖HTSS〗〓To investigate the effect of microRNA(miR146) on rheumatoid arthritis(RA) fibroblastlike synoviocytes(FLS) through  PI3K/Akt signaling pathway.
〖HTH〗〖WTHZ〗Methods〖HTSS〗〓RAFLS cells were divided into the control group, lipopolysaccharide(LPS) group and LPS+miR146 group. After transfection of miR146 in the LPS+miR146 group, the LPS group and the LPS+miR146 group were incubated with LPS for 24 h, respectively. The cell proliferation was determined by methylthiazolyldiphenyltetrazolium. The Flow cytometry was used to detect cell apoptosis. The levels of interleukin1β(IL1β), interleukin6(IL6) and tumor necrosis factorα(TNFα) in supernatants were determined by enzymelinked immunosorbent assay. The realtime quantitative polymerase chain reaction was used to detect the expression of miR146, PI3K and Akt mRNA. Western blotting was used to detect the expression of PI3K, Akt and phosphorylated(p)Akt.
〖HTH〗〖WTHZ〗Results〖HTSS〗〓Compared with LPS group, the expression of miR146 in LPS+miR146 group was significantly increased(P＜005), the proliferation of RAFLS cells was significantly decreased(P＜005), and the apoptosis was significantly increased(P＜005). Compared with LPS group, the contents of IL1β, IL6 and TNFα in the supernatant in LPS+miR146 group were significantly decreased(P＜005), the expression of PI3K mRNA and protein in LPS+miR146 group was downregulated(P＜005), and the expression of Akt mRNA and protein in LPS+miR146 group was not significantly changed(P＞005), and the expression of pAkt protein in LPS+miR146 group was significantly decreased(P＜005).
〖HTH〗〖WTHZ〗Conclusion〖HTSS〗〓miR146 may regulate the proliferation, apoptosis and inflammatory factors of RAFLS cells by interfering with PI3K/Akt signaling pathway.

Key words: arthritis, rheumatoid, microRNA146, phosphoinositide 3kinase