Fig. 4

miR-146a-5p-modified exosomes reduced toxicity of neurotoxic astrocytes in vitro. a b Representative western blot images and quantitative analysis of C3 and Lcn2 gene expression in control astrocytes, mixture(TNFα, IL1β, C1q)-induced astrocytes (neurotoxic astrocytes) and ExoN/ExoOE treated neurotoxic astrocytes. c Representative immunostaining images of GFAP (red)/C3 (green)/Lcn2 (green) and the quantification of the relative immunofluorescence intensity of C3 and Lcn2 in each group. Scale bar = 50 μm. d, e Representative images and quantitative analysis of neurite length in NGF-stimulated PC12 cells treated with conditioned medium of primary astrocytes (Control), neurotoxic astrocytes (Mix) and ExoN/ExoOE treated neurotoxic astrocytes (Mix-ExoN or Mix-ExoOE). Scale bar = 50 μm. f Cell viability of PC12 cells treated with conditioned medium of different groups. Data above are represented as mean ± SD. *, p < 0.05; **, p < 0.01. ExoN normal exosome, ExoOE miR-146a-5p-modified exosome