Figure 6: Myricetin inhibits rotenone-induced phosphorylation of STAT3 and SMAD1/5/9. Cells were pretreated with 1 × 10–6 M myricetin for 1 hour, followed by co-treatment with 400 nM rotenone for 24 hours. (A) Original bands of phosphorylated and total STAT3 and SMAD1 in MES23.5 cells. β-Actin was used as a loading control. (B) Quantitative results of pSTAT3 expression, expressed as the optical density ratio to total STAT3. (C) Quantitative results of pSMAD1/5/9, expressed as the optical density ratio to total SMAD1. Data represent mean ± SD (n = 7 in B, 6 in C). **P < 0.01, ***P < 0.001, vs. control group; #P < 0.05, ###P < 0.001, vs. rotenone group (one-way analysis of variance followed by post hoc Tukey’s test). p: Phosphorylated; SMAD: drosophila mothers against decapentaplegic protein; STAT3: signal transducer and activator of transcription 3.