Figure 4.

Anti-inflammatory effects of HA-NPs in bone-marrow-derived macrophages (BMDMs). (a) The concentrations of pro-inflammatory markers of nitric oxide (NO) (upper left), tumor necrosis factor (TNF) (upper right), interleukin-6 (IL-6) (lower left), and interleukin-12 (IL-12) (lower right), excreted by BMDMs that were stimulated with lipopolysaccharide (LPS) and interferon-γ (INF-γ) for 24 h (Control) or that were first pre-stimulated for 24 h with HA-NPs at three concentrations of 25 μg/mL, 200 μg/mL, or 1000 μg/mL and subsequently stimulated with LPS and INF-γ. Free oligomeric HA was used at the same concentrations and using the same protocol as mentioned above. In the lower-left panel, “#” indicates significantly higher concentration compared to control, HA-NPs (all concentrations), and HA at 25 μg/mL. In the lower right panel, significant differences “*” are shown only for control and HA-NPs 1000 μg/mL; (b) Expression of arginase-1 gene (Arg-1) (relative induction compared to naive macrophages), which is associated with the pro-fibrotic macrophage phenotype. BMDMs were stimulated either with interleukin-4 (IL-4) for 24 h (Control) or were first pre-stimulated with HA-NPs or HA for 24 h at the concentrations mentioned above and subsequently stimulated with IL-4. “#” indicates significantly higher values compared to control at p < 0.05. Adapted with permission from [67]. Copyright 2017, American Chemical Society.