Metformin Attenuates Experimental Autoimmune Arthritis through Reciprocal Regulation of Th17/Treg Balance and Osteoclastogenesis
Figure 5
Metformin suppresses osteoclastogenesis in vitro. C57BL/6 mice preosteoclasts were cultured in the presence of 10 ng/mL M-CSF and/or 50 ng/mL RANKL in the presence or absence of metformin 1 mM. (a) Differentiated osteoclasts were stained for TRAP (scale bar = 200 μm) and The TRAP+ cells were indicated in graph (under). (b) The mRNA levels of TRAP, MMP-9, calcitonin receptor, carbonic anhydrase II, cathepsin K, integrin 3, HIF1-, and AMPK were quantified by real-time PCR. (c) Protein levels of pAMPK, TRAF6, pmTOR, mTOR, pSTAT3 Y705, pSTAT3 S727, STAT3, and -actin were analyzed using Western blot in osteoclasts. (d) Immunohistochemical detection of TRAF6, pmTOR pSTAT3 Y705, and pSTAT3 S727 were stained in the synovium of CIA and metformin-treated CIA. All tissues were counterstained with hematoxylin (original magnification, ×400) (scale bar = 50 μm). Data are presented as the mean ± SD of four independent experiments (; ; ).
