Fig. 1

Taxifolin suppressed hyperproliferation of epidermis and expression levels of pro-inflammatory cytokines (IL-1α, IL-1β, and IL-6) and chemokines CXCL8 and CCL20) in TNF-α treated HaCaT cells. A Structure of taxifolin, B Cytotoxicity of taxifolin to HaCaT cells. Taxifolin did not show any cytotoxicity at concentrations up to 300 μg/mL. C TNF-α-induced epidermal hyper-proliferation was suppressed by taxifolin in a concentration-dependent manner. Here, the non-cytotoxic concentration of taxifolin was set to be 20 ug/ml and brazilin was used as positive control. D IL-1α mRNA expression levels in TNF-α induced HaCaT cells were verified by real-time RT-PCR. Taxifolin downregulated IL-1α mRNA expression in a concentration-dependent manner. Taxifolin inhibited E IL-1β F IL-6 gene expression levels in TNF-α signal pathway. Taxifolin also inhibited expression levels of chemokines such as G CXCL8 and H CCL20 in TNF-α treated HaCaT cells. #, p < 0.05; ##, p < 0.01; and ###, p < 0.001 versus control; *, p < 0.05, **, p < 0.01 versus TNF-α treated HaCaT cells