Fig. 6

Inhibition of TGFβ1/Smad3 signaling pathway impair the effect of ATRA on suppressing proinflammatory responses. a qRT-PCR results showing the relative mRNA levels of key molecules of the TGFβ1/Smad3 signaling pathway (TGF-β1, TGFBR1, TGFBR2 and Smad3). and inflammatory cytokines (TGF-β1. IL-10,TNF-α, IL-1β, IL-6 and IL-17). b Supernatant concentrations of TGF-β1. IL-10, TNF-α, IL-1β, IL-6, and IL-17. For all, data were presented as mean ± SEM. The same letter indicates no significant difference (p > 0.05), whereas different letters indicate a significant difference (p < 0.05)