Fig. 3

Oral LG283 administration ameliorates bleomycin-induced skin fibrosis regardless of inflammation in mice. a The antifibrotic effects of LG283 were analyzed in the back skin of mice receiving daily subcutaneous injections of bleomycin concurrent with daily oral gavage of LG283 or placebo (sterilized olive oil) for 4 weeks. Representative images of H&E stained (upper columns) and Masson’s trichrome stained tissue (lower columns). Double-headed allows indicate the measured length of dermal thickness. Scale bar, 200 μm. b Skin fibrosis in bleomycin-injected mice with or without oral LG283 was compared by determining dermal thickness and ratio of trichrome-stained area/total area. Values represent mean ± SEM; n =10 each group; **p ≤ 0.01. c Skin fibrosis in bleomycin-injected mice with or without oral LG283 was evaluated by expression of COL1A2 and FN1. Values were normalized to GAPDH levels and are shown as the mean of fold change compared to vehicle control; n=3 each group. All values represent mean ± SEM; **p ≤ 0.01. Molecular weights of the paneled proteins; 130 kDa (COL1A2), 250 kDa (FN1), and 37 kDa (GAPDH). d Oral LG283 suppressed the bleomycin-induced decrease of CD31-positive dermal capillary vessels in mice. Representative immunohistochemistry images of day 28 are shown (left). Scale bar, 50 μm. Quantitative analysis is shown in the bar graph (right). Values represent mean ± SEM; n =3 each group; *p ≤ 0.05. e Oral LG283 did not affect the infiltration of F4/80-positive or CD3-positive leukocytes in the skin of mice after 7 days of daily bleomycin injections. Representative images are shown (left). Scale bar, 50 μm. Quantitative analysis is shown in the bar graph (right). Values represent mean ± SEM; n =5 in each group. f Oral LG283 did not change the infiltration of inflammatory CD11b⁺Ly6C^hi monocytes and profibrotic CD11b⁺CD204⁺ M2 macrophages analyzed by flow cytometry after 21 days of bleomycin injection. Values represent mean ± SEM; n = 5 each group