Journal: Neural Regeneration Research
Article Title: Spinal cord injury–derived exosomes exacerbate damage: miR-155-5p mediates inflammatory responses
doi: 10.4103/NRR.NRR-D-24-01451
Figure Lengend Snippet: MiR-155-5p exacerbates spinal cord inflammatory responses by promoting M1 microglia polarization. (A, B) Heatmap (A) and scatterplot (B) of four upregulated and two downregulated miRNAs with ≥2.0-fold difference between Sham-Exos and SCI-Exos derived from spinal cord tissue ( n = 5). (C) Expression of the top four miRNAs in SCI-Exos and Sham-Exos ( n = 3). (D) miR-155-5p levels in the spinal cord after intervention with agomiR-155-5p and agomiR-Nc ( n = 3). (E) mRNA expression of inflammatory cytokines IL-1β, IL-6, TNF-α, and IL-10 in rats after treatment with agomiR-155-5p ( n = 3). (F) Expression of the M1 polarization-related gene CD86 in rats treated with agomiR-155-5p ( n = 3). (G) Expression of proinflammatory chemokines Cxcl2, Ccl2, and Ccl5 in SCI and Sham rats treated with agomiR-155-5p ( n = 3). (H) miR-155-5p levels in BV2 microglia treated with miR-155-5p mimic ( n = 3). (I) Higher miR-155-5p mimic concentrations (0, 100, 200, and 500 nM) had higher expressions of IL-1β and IL-6 in miR-155-5p mimic-treated BV2 cells ( n = 6, 4). (J) Higher miR-155-5p mimic concentrations (0, 100, 200, and 500 nM) had higher expression of TNF-α in miR-155-5p mimic-treated BV2 cells ( n = 4). (K) Expression of the M1 polarization-related gene CD86 in BV2 cells treated with miR-155-5p mimic ( n = 4). (L) Immunofluorescence analysis suggested a positive relationship between miR-155-5p mimic concentration (0, 100, 200, 500 nM) and CD86 expression in BV2 cells treated with miR-155-5p mimic. Scale bars: 100 μm. CD86, red; DAPI, blue. (M) Quantification of fluorescence intensities in L ( n = 3). * P < 0.05, ** P < 0.01, *** P < 0.001, **** P < 0.0001 (two-tailed unpaired Student’s t -test [C] or one-way analysis of variance followed by Tukey’s post hoc test [D–K, M]). Ccl: C–C motif chemokine ligand; CD: cluster of differentiation; Cxcl: C–X–C motif chemokine ligand; DAPI: 4′,6-diamidino-2-phenylindole; IL: interleukin; miR: microRNA; NC: negative control; PBS: phosphate-buffered saline; SCI: spinal cord injury; SCI-Exos: SCI-generated tissue exosomes; Sham-Exos: exosomes derived from normal spinal cord tissues; TNF: tumor necrosis factor.
Article Snippet: Additionally, miRNAs were reverse-transcribed into cDNA using the miRNA First Strand cDNA Synthesis Kit (Sangon Biotech).
Techniques: Derivative Assay, Expressing, Immunofluorescence, Concentration Assay, Fluorescence, Two Tailed Test, Negative Control, Saline, Generated
![MiR-155-5p exacerbates spinal cord inflammatory responses by promoting M1 microglia polarization. (A, B) Heatmap (A) and scatterplot (B) of four upregulated and two downregulated <t>miRNAs</t> with ≥2.0-fold difference between Sham-Exos and SCI-Exos derived from spinal cord tissue ( n = 5). (C) Expression of the top four miRNAs in SCI-Exos and Sham-Exos ( n = 3). (D) miR-155-5p levels in the spinal cord after intervention with agomiR-155-5p and agomiR-Nc ( n = 3). (E) mRNA expression of inflammatory cytokines IL-1β, IL-6, TNF-α, and IL-10 in rats after treatment with agomiR-155-5p ( n = 3). (F) Expression of the M1 polarization-related gene CD86 in rats treated with agomiR-155-5p ( n = 3). (G) Expression of proinflammatory chemokines Cxcl2, Ccl2, and Ccl5 in SCI and Sham rats treated with agomiR-155-5p ( n = 3). (H) miR-155-5p levels in BV2 microglia treated with miR-155-5p mimic ( n = 3). (I) Higher miR-155-5p mimic concentrations (0, 100, 200, and 500 nM) had higher expressions of IL-1β and IL-6 in miR-155-5p mimic-treated BV2 cells ( n = 6, 4). (J) Higher miR-155-5p mimic concentrations (0, 100, 200, and 500 nM) had higher expression of TNF-α in miR-155-5p mimic-treated BV2 cells ( n = 4). (K) Expression of the M1 polarization-related gene CD86 in BV2 cells treated with miR-155-5p mimic ( n = 4). (L) Immunofluorescence analysis suggested a positive relationship between miR-155-5p mimic concentration (0, 100, 200, 500 nM) and CD86 expression in BV2 cells treated with miR-155-5p mimic. Scale bars: 100 μm. CD86, red; DAPI, blue. (M) Quantification of fluorescence intensities in L ( n = 3). * P < 0.05, ** P < 0.01, *** P < 0.001, **** P < 0.0001 (two-tailed unpaired Student’s t -test [C] or one-way analysis of variance followed by Tukey’s post hoc test [D–K, M]). Ccl: C–C motif chemokine ligand; CD: cluster of differentiation; Cxcl: C–X–C motif chemokine ligand; DAPI: 4′,6-diamidino-2-phenylindole; IL: interleukin; miR: microRNA; NC: negative control; PBS: phosphate-buffered saline; SCI: spinal cord injury; SCI-Exos: SCI-generated tissue exosomes; Sham-Exos: exosomes derived from normal spinal cord tissues; TNF: tumor necrosis factor.](https://pub-med-central-images-cdn.bioz.com/pub_med_central_ids_ending_with_1823/pmc13211823/pmc13211823__NRR-21-2514-g006.jpg)