Fig. 2.

Quercetin attenuates LPS-induced inflammatory response in lamellar keratinocytes. A Chemical structure of quercetin (C₁₅H₁₀O₇). B The cellular metabolic activity of lamellar keratinocytes (passages 2–4) was assessed by CCK-8 assay after treatment with various concentrations of quercetin (0-100 µM) for 24–48 h. C The cellular metabolic activity of keratinocytes co-treated with LPS (10 µg/mL) and quercetin (0–50 µM) for 24 h. D-K Secretion levels of (D) TNF-α, (E) IL-6, (F) IL-1β, (G) IL-10, (H) CXCL-1, (I) CXCL-6, (J) COX-2, and (K) iNOS in cell supernatants, as determined by ELISA. The data are presented as mean ± standard deviation from three independent biological replicates (n = 3). The symbol “+” in the diagram indicates the addition of a substance, while “-” denotes no addition. The symbol * indicates P < 0.05, and ** indicates P < 0.01