Fig. 4

M1 macrophage polarization and obesity-related neutrophilic airway inflammation were reduced in a female db/db murine model. a Flow chart for the generation of a female obesity-related neutrophilic airway inflammation mouse model. b Neutrophil, eosinophil, macrophage, and lymphocyte percentages in BALF. c Representative H&E-stained histological lung sections and a bar graph showing the inflammation scores. Scale bar = 50 μm. d Representative PAS-stained histological lung sections and a bar graph showing the PAS scores. Scale bar = 20 μm. e The levels of inflammatory cytokines (IFN-γ, TNF-α, IL-1β, IL-6, and IL-17A) in lung homogenates. f Representative histogram of CD11c (M1) expression (left) and quantitative analysis of CD11c (right) expression in BALF. g Representative histogram of CD86 (M1) expression (left) and the quantitative analysis of CD86 (right) expression in BALF. h Representative flow cytometry analysis of M1 macrophages (CD11c⁺CD86⁺) (gating on macrophages) (left) and quantitative analysis of the M1 macrophage number (right) in lung single-cell suspensions. i Western blot analysis of iNOS in lung tissues; GAPDH was used as a loading control. The displayed protein expression value is the ratio of iNOS protein to total protein. The data are expressed as the means ± SDs. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001. i.t., intratracheal; i.p., intraperitoneal. For b–d and f, g, n = 5 female mice per group; for e, n = 4–5 female mice per group; for h, n = 4 female mice per group; for i, n = 3 female mice per group