Fig 2: Effects of lncRNA-MM2P on the expression of pro-inflammatory cytokines in the supernatants of MSU-induced cells. The mRNA expression of inflammatory cytokines, (A) IL-1ß, (B) IL-8 and (C) TNFa, increased in the supernatants of RAW 264.7 cells after MSU treatment, and these effects were more notable when lncRNA-MM2P-1 was knocked down in cells. The mRNA expression of inflammatory cytokines, (D) IL-1ß, (E) IL-8 and (F) TNFa, increased in the supernatant of THP-1 cells after MSU treatment, and these effects were more notable when lncRNA-MM2P-1 was knocked down in cells. The mRNA expression of inflammatory cytokines, (G) IL-1ß, (H) IL-8 and (I) TNFa, increased in the supernatant of RAW 264.7 cells after MSU treatment, and these effects were reversed in lncRNA-MM2P-1 overexpressing cells. The mRNA expression of inflammatory cytokines, (J) IL-1ß, (K) IL-8 and (L) TNFa, increased in the supernatant of THP-1 cells after MSU treatment, and these effects were reversed in lncRNA-MM2P-1 overexpressing cells. *P<0.05, **P<0.01. lncRNA, long non-coding RNA; MSU, monosodium urate; IL, interleukin; TNF, tumor necrosis factor; ns, not significant.

Fig 3: Hyperphosphorylated tau aggregates induced significantly higher levels of all three pro-inflammatory cytokines than heparin-induced WT aggregates.(i) TNF-a, (ii) IL-1ß, and (iii) CCL5 ELISA assays were conducted on both a THP-1 human macrophage cells and b primary human macrophage cells to determine the pro-inflammatory responses mediated treatment by LPS, s-tau monomer or aggregates or heparin-induced WT aggregates or its monomeric control with or without the TLR4 antagonists RsLA or Tak-242. LPS and PBS served as the positive and negative controls. The P-values are based on unpaired two-sided Student’s t-test: **p < 0.01, ***p < 0.001, n.s. non-significant. Data are presented as mean values ± s.d. of three independent experiments except for a-(i) which had four independent experiments. Source data are provided as a Source Data file.

Fig 4: Cellular and temporal expression of Tnf mRNA in the thoracic spinal cord after SCI. (a–i) In situ hybridization was used to investigate the distribution of Tnf mRNA+ cells the first 24 h after SCI. Tnf mRNA expression was undetectable in naïve mice (a). Tnf mRNA+ cells in the white matter of the posterior funiculi (arrows in b) and in neuronal-like cells in the dorsal horn (arrowhead in c), at 1 h after SCI. Tnf mRNA+ cells in the white matter of the posterior funiculi (d) and in the grey matter of the ventral horn (e). At 3 h, most cells displayed macrophage- or glial-like morphology (arrows in f). By 6 h (g), 12 h (h), and 24 h (i), Tnf mRNA+ cells were mainly located in white matter areas of the damaged spinal cord (arrows). (j) Parallel spinal cord sections that were in situ hybridized for glyceraldehyde-3-phosphate dehydrogenase (Gapdh) mRNA showed a largely neuronal signal and confirmed the overall suitability of the tissue for in situ hybridization. (k,l) Parallel sections hybridized with buffer alone (k) or pretreated with RNAse A before the in situ hybridization (l) were devoid of signal. (m–o) RT-qPCR analysis of Tnf mRNA (m), Tnfrsf1a mRNA (n), and Tnfrsf1b mRNA (o) levels in naïve mice and in mice allowed 1, 3, 6, and 12 h and 1, 3, 7, 14, and 28-days survival after SCI. Tnf mRNA levels were significantly increased at 1, 3, and 6 h and 7 days after SCI, compared to naïve mice (Time: p < 0.0001, F9,39 = 58.14) (m). Tnfrsf1a mRNA levels significantly increased from 6 h to 28 days after SCI, compared to naïve mice (Time: p < 0.0001, F9,39 = 20.01) (n). Tnfrsf1b mRNA levels significantly increased at 3 h after SCI, compared to naïve mice (Time: p = 0.009, F9,39 = 2.965). Results are expressed as mean ± SEM, n = 5/group, * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001. Scale bars: (a–c, f–i, k,l) = 40 µm, (d,e) = 100 µm, and (j) = 200 µm.

Fig 5: TLR4 activation could reverse the inhibitory effect of n-3 PUFAs on hippocampal neuroinflammation. (A) Nissl staining detection of neuron damage. (B-D) qPCR detection of IL-6 mRNA, IL-1ß mRNA and TNF-a mRNA in the hippocampus of mice. (E-G) ELISA detection of the concentration of IL-6, IL-1ß, and TNF-a of hippocampus in mice. *p < .05, **p < .01, ***p < .001. IL, Interleukin; mRNA, messenger RNA; PUFAs, polyunsaturated fatty acids; qPCR,Quantitative real time polymerase chain reaction; TLR4, toll-like receptor 4; TNF, tumor necrosis factor.