Figure 4.

let-7c-5p ameliorated LPS-induced pulpitis by suppressing DMP1-mediated NF-κB signaling in vivo. SD rats were first injected with NC or let-7c-5p agomir and then subjected to pulpitis induction using LPS. At 9 h after LPS administration, rats were sacrificed and the dental tissues were collected for H&E staining, immunochemistry, RT²-PCR, and Western blot analysis. LPS decreased the level of let-7c-5p in dental tissues and injection of let-7c-5p agomir restored the level (A). As shown by H&E staining, LPS induced neutrophil infiltration in dental tissues and let-7c-5p agomir inhibited the LPS-induced neutrophils infiltration (B). LPS also increased the expression and distribution of DMP1 (C, D), which further induced the activation of NF-κB signaling (D). However, increased expression of let-7c-5p by agomir injection effectively inhibited the LPS-induced activation of DMP1/NF-κB signaling transduction. * P<0.05 vs. Blank group. ^# P<0.05 vs. LPS group. Arrows indicate neutrophil infiltration detected by H&E staining. Scale bar for H&E staining, 100 μm. Scale bar for immunochemistry, 50 μm. Each assay was represented by 6 replicates.