Figure 6.

Metformin Inhibited Inflammatory Cytokines by Promoting AMPK

Expression levels of inflammatory cytokines were measured after culturing RA-FLSs with normal saline or metformin for 36 h (n = 3). (A) Compared to controls, expression levels of AMPK-α1 and PKA-α1 genes were significantly increased while the expression of IL-6 was significantly decreased in metformin-treated RA-FLSs. (B and C) Negative correlation of AMPK-α1 with RAPTOR (B) and IL-6 (C) gene expression. (D) Western blot analysis of IL-1β and TNF-α levels. (E) Negative correlation between p-AMPK-α1 and TNF-α levels. A representative example from three independent experiments is shown. ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001, ∗∗∗∗p < 0.0001.