Fig. 4: Therapeutic efficacy evaluation of TYR degradation in a mouse hyperpigmentation model.

a Schematic of the experimental plan in the mouse hyperpigmentation model. b Images of square pigmentation patterns on the backs of mice treated with (1) blank control, (2) VH032, (3) Alk-TIn, (4) VH032 + Alk-TIn, (5) epi-VH032-Azi3 + Alk-TIn + SA, (6) DeTYR-3 and (7) VH032-Azi3 + Alk-TIn + SA creams at different time points (0, 24 and 48 h). c Fontana-Masson (FM) staining of melanin in mouse skin. (n  =  3 independent samples). d Normalized pigmentation level in different treatment groups by digital image analysis using Image J. (n  =  3 biological replicates). Data are presented as mean ± standard deviation (SD). ****P < 0.0001. e Melanin contents of mouse skin samples treated with different groups for 48 h. (n  =  5 biological replicates). Data are presented as mean ± standard deviation (SD). ****P  <  0.0001. f Western blot assay of TYR and MITF in mice skin samples treated with different groups for 48 h. (n  =  3 independent experiments). g H&E staining of mouse skin tissues treated with different groups for 48 h. (n  =  3 independent samples). Statistical analysis was performed using ONE-WAY variance (ANOVA) by Dunnett’s multiple comparisons.