Effects of KGO ointment on epithelial thickness and changes in collagen fibre in HRM-2 mice. After 5 weeks, the epithelial thickness of the skin was observed after staining with H&E (A,B). A significant reduction was found in the epidermal thickness of the KGO ointment-treated groups. Values in the bar graphs are ± SEM from three independent experiments. *** p < 0.001, ** p < 0.05, and * p < 0.01 when compared with the UVB control. (C) The intensity of M-T staining was decreased in the UVB-control group compared to the normal group, suggesting that collagen fibre degradation progressed, and wrinkle formation accelerated. However, the amount of collagen fibres in the KGO ointments (1 and 0.5%) and positive control group increased, indicating that KGO ointments reduced the amount of collagen degradation. The normal mice are abbreviated as HRM-2 N; the UVB control is abbreviated as UVB-C; sunblock is abbreviated as SB.