Fig. 6

RBA-NPs drive M1-to-M2 phenotypic switch by down-regulating the glycolysis level via blocking ERK/HIF-1α/GLUT1 pathway. a Volcano plot of all proteins identified in this study. Red and blue dots indicate up-or down-regulated proteins significantly, respectively (folds change of >1.5 or <0.667 and p-value of <0.05). b Significantly changed pathways of the differentially expressed up-regulated genes based on the KEGG analysis. The proteins affected by RBA-NPs treatment were enriched in fatty acid metabolism, glycolysis and other pathways. c–e The histogram of ECAR, relative ATP, lactate levels in different groups. The production of ECAR, relative ATP, lactate could reflect the glycolysis ability. Data represent mean ± SD (n = 5). *P < 0.05 vs. M0 group; ^#P < 0.05 vs. M1 group. f–h IL-1β, TNF-α, and IL-6 levels were analyzed by the kits. Data represent mean ± SD (n = 5). *P < 0.05 vs. M0 group; ^#P < 0.05 vs. M1 group. i Immunofluorescence staining of LDHA (green) and nuclei (blue) on M1 macrophages in different groups. Scale bar = 20 μm. LDHA was the last step in the process of catalytic glycolysis and an important indicator for measuring glycolysis process. j Immunofluorescence staining of ERK (red), HIF-1α (green), GLUT1 (red) and nuclei (blue) on M1 macrophages in different groups. Scale bar = 20 μm. RBA-NPs significantly blocked ERK/HIF-1α/GLUT1 pathway. k The proportions of M1 phenotype macrophages (CD86 + ) and M2 phenotype macrophages (CD206 + ) on M1 macrophages in different groups without or with treatment siERK were detected by flow cytometry assay. l The expressions of M1 phenotype (iNOS, TNF-α, IL-1β) and M2 phenotype (Arg-1, IL-10, TGF-β) macrophage makers genes were detected. Data were expressed as mean ± SD, n = 4. ^#P < 0.05 vs. Normal group; *P < 0.05 vs. M1 group