Fig. 6

Urate suppresses neuroinflammation induced by activated microglia in a rat model of LPS-induced PD. a Schematic illustration of the schedule for urate and LPS administration. b Motor coordination was evaluated with the rotarod test at 0, 3, and 4 weeks after LPS injection (n = 4–9/group). c Plasma concentration of urate was assessed with a fluorometric assay (n = 4–9/group). d–g Representative images of TH immunoreactivity in the STR (d, n = 4–5/group, scale bar = 1000 μm) and SN (f, n = 4–5/group, scale bar = 500 μm). Quantitative analysis of TH-positive fibers in STR shown as the intensity of intact side (left, L) and lesioned side (right, R) (e). Quantitative analysis of TH-positive cells in SN, shown as the number of TH-positive cells in intact side and lesioned side (g). h–m Representative images of Iba-1 immunoreactivity in the STR (h, n = 4–5/group, scale bar = 50 μm) and SN (k, n = 4–5/group, scale bar = 50 μm). Quantitative analysis of Iba-1-positive cells in STR (i) and SN (l), shown as the number of cells per square millimeter in intact side and lesioned side, respectively. Quantitative analysis of branch length and cell body diameter of Iba-1-positive cells, shown as the absolute of branch length and cell body diameter lesioned side in STR (j) and SN (m). n, o Representative images of immunofluorescence analysis of TH-positive (red) and Iba-1-positive (green) cells in the lesioned side of SN (n, n = 4–5/group, scale bar = 100 μm). Quantitative analysis of fluorescence intensity of Iba-1-positive cells in lesioned side (o). Quantification of TH-positive cells in SN was counted by sterology using Stereo Investigator software. TH-positive fibers in STR and Iba-1 positive cells in the STR and SN were performed using Image Pro Plus v5.0 image analysis software. p–r Protein expression in SN was assessed in animals subjected to the indicated treatments (n = 4–5/group). Tissue lysates were analyzed for expression of URAT1 and IL-1β by Western blotting (p). The levels were normalized to GAPDH and quantified as the ratio of the lesioned side to the intact side (q, r). s Tissue lysates were prepared and TNF-α concentration of SN was assessed by ELISA (n = 4–5/group). Rats injected with vehicle served as the sham. Data represent the mean ± SD. ^*p < 0.05, ^**p < 0.01, ^***p < 0.001 vs. sham group; ^#p < 0.05, ^##p < 0.01, ^###p < 0.001 vs. LPS group (one-way analysis of variance)