Fig. 6: TRPV1 activation attenuated microgliosis and microglial lipid accumulation in ApoE4 HFD mice.

a Heatmap showing gene expression profiles correlated with microglial proinflammatory reactions (Cluster 1) and normal functions (Cluster 2). b Differentially expressed Cluster 1 genes between HFD-fed ApoE3 and ApoE4 mice from the heatmap (a). c Immunofluorescent images of Iba-1⁺ cells of ApoE3 and ApoE4 mice in the cerebral cortex (upper panel) and amplified single Iba-1⁺ cells (lower panel). d Morphological analyses of Iba-1⁺ cells from the immunofluorescence micrographs (c). Blue bars indicate ApoE3 mice, and red bars indicate ApoE4 mice. e Representative immunofluorescent images of FITC-labeled Aβ_1-42 and Iba-1⁺ cells of ApoE3 and ApoE4 mice. f Quantification of Aβ_1–42 uptake in Iba-1⁺ cells. g, h Representative immunofluorescent images and quantification of MAP2 in primary cortical neurons. i, j Representative immunofluorescent images and quantification of BODIPY⁺ puncta in primary neurons. n = 3 mice per group. Statistical tests: two-sided Student’s t test (b), two-way ANOVA followed by Sidak’s multiple comparison test (d), one-way ANOVA followed by Tukey’s post hoc test (f, h, j). Data represent the mean ± s.e.m. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. Scale bars, 50 μm (c upper panel), 20 μm (c lower panel), 25 μm (e).