Fig. 5

miR-21 induces pro-inflammatory response through TLR7 activation. A Relative mRNA levels of miRNAs (Let-7b, miR-133a, miR-148a, miR-208a, miR-21, and miR-29a) in the kidneys of mice fed normal chow diet or adenine diet for 3 weeks. *p < 0.05 versus normal chow diet-fed mice. **p < 0.01 versus normal chow diet-fed mice. ***p < 0.001 versus normal chow diet-fed mice. B Representative ISH images of mir-21-5p (red) in the kidneys of mice fed a chow diet or adenine diet (upper panner). Representative ISH images of mir-21-5p (red) and Col1a2 (green) in the kidneys of mice fed a chow diet or adenine diet (lower panner). Scale bar = 50 μm. C Representative ISH images of mir-21-5p (red) and Tlr7 (green) in fibrotic kidney. Scale bar = 50 μm. D Relative mRNA levels of miR-21-5p in NRK52E cells treated with LPS were measured. **p < 0.01 versus control cells. E Protein levels of p65 and phosphorylated-p65 in NRK52E cells transfected with miR-21-5p were measured. β-actin was used as a loading control. F NF-κB activity in NRK52E cells treated with miR-21-5p was measured using the NF-κB promoter luciferase assay. #p < 0.05 versus blank group. *p < 0.05 versus control group. G Relative mRNA levels of pro-inflammatory chemokines (Ccl2, Il8, and Cxcl1) in NRK52E cells treated with miR-21-5p. *p < 0.05 versus N.C treated group. H NF-κB activity in NRK52E cells treated with miR-21-5p and M5049 was measured using the NF-κB promoter luciferase assay. #p < 0.05 versus control group. *p < 0.05 versus miR-21 treated group. I Relative mRNA levels of the pro-inflammatory chemokines (Cxcl1, Il8, and Ccl2) in NRK52E cells treated with miR-21-5p and M5049. #p < 0.05 versus control group. *p < 0.05 versus miR-21 treated group. J Relative Tlr7 mRNA levels in NRK52E cells transfected with TLR7 siRNA. ***p < 0.001 versus negative control group. K Protein level of TLR7 in NRK52E cells transfected with TLR7 siRNA. β-actin was used as a loading control. L Relative mRNA levels of the pro-inflammatory chemokines (Cxcl1, Il8, and Ccl2) in NRK52E cells transfected with TLR7 siRNA. miR-21 was further transfected after TLR7 knockdown. #p < 0.05 versus negative control group. *p < 0.05 versus negative control and miR-21 transfected group