Fig. 7. Molecular interactions of emodin with EGFR and MAP kinase proteins. The 2D interaction diagram depicts emodin’s interactions with (A) EGFR, (B) MEK1, (C) MEK2, (D) ERK1, (E) ERK2, and (F) p38 MAPK. Molecular docking studies revealed that emodin exhibited strong binding interactions with EGFR, MEK1/MEK2, ERK1/ERK2, and p38 MAPK proteins, with binding affinities ranging from ‒8.3 to ‒9.5 kcal/mol (
Table 1,
Fig. 7). Among these interactions, emodin showed the highest binding affinity for MEK2 (‒9.5 kcal/mol;
Fig. 7C) and the lowest for ERK2 (‒8.3 kcal/mol;
Fig. 7E). Additionally, emodin exhibited moderate interactions with the EGFR and p38 MAPK (‒8.6 kcal/mol) (
Fig. 7A,
7F), forming two and four conventional hydrogen bonds, respectively (
Table 1). These results suggest that emodin suppresses MUC5AC gene expression by inhibiting the activation of EGFR-MAPK pathway through interacting with each protein.
