NRF2 Activation Inhibits Both TGF-β1- and IL-13-Mediated Periostin Expression in Fibroblasts: Benefit of Cinnamaldehyde for Antifibrotic Treatment

Figure 6

The involvement of NRF2 signaling in the downregulation of IL-13- and TGF-β1-induced tenascin-C, VEGF, and CTGF mRNA expression by cinnamaldehyde. (a–c) Knockdown of NRF2 reverses the effects of cinnamaldehyde (CIN) on TGF-β1-induced mRNA expression of TNC, VEGF, and CTGF. (d–f) Knockdown of NRF2 reverses the effects of CIN on IL-13-induced mRNA expression of TNC, VEGF, and CTGF. NHDF cells were transiently transfected with control siRNA or 5 nM NRF2 siRNA for 24 h; next, cells were precultured with 25 μM CIN for 30 min and then treated with 5 ng/mL TGF-β1 or 50 ng/mL IL-13 or left untreated for 48 h. mRNA expression levels of TNC, VEGF, and CTGF are depicted. The values were adjusted by GAPDH expression. The same experiments were performed three times. , . NS: not significant.

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