Identification of Sitogluside as a Potential Skin-Pigmentation-Reducing Agent through Network Pharmacology

Figure 4

Sitogluside can downregulate the TYR expression through inhibiting the ERK/MAPK and p38/MAPK pathway. (a) The changes of melanogenesis-related gene protein levels in MNT1 and B16F0 cells treated with different concentrations of sitogluside were detected by western blotting. (b) The expression of key proteins in MAPK and PKA pathways was determined by western blotting. (c) Sitogluside can reduce the protein content of TYR by inhibiting the phosphorylation level of ERK activated by PMA. (d) Sitogluside can reduce the protein content of TYR by inhibiting the phosphorylation level of ERK activated by anisomycin. (e) Fontana-Masson melanin staining suggests that sitogluside (200 μM) can reduce melanin content increased by PMA (25 ng/mL). (f) Fontana-Masson melanin staining suggests that sitogluside (200 μM) can reduce melanin content increased by anisomycin (4 nM). (g) The molecular docking between sitogluside and opioid u receptor, melanocortin 1 receptor, stem cell factor receptor, endothelin B receptors, adrenergic β receptor, and prostaglandin receptor. PMA: 12-O-tetradecanoyl phorbol-13-acetate; Sito: sitogluside; Anis: anisomycin.

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