MicroRNA let-7c Improves LPS-Induced Outcomes of Endometritis by Suppressing NF-κB Signaling.

Endometritis is a common inflammatory disease which endangers human and animal reproductive health. MicroRNA (miRNA) let-7c plays an important role in the inflammatory process; however, the regulatory underlying mechanism of let-7c in endometritis is unclear. In this study, we confirmed that let-7c was significantly reduced in LPS-induced mouse endometritis model, and overexpression of let-7c was able to effectively reduce uterine tissue damage caused by lipopolysaccharide (LPS), and then, a LPS-induced bovine endometrial epithelial cell (BEND) line was used to mimic the inflammatory model in vitro. Our data showed that overexpression of let-7c significantly reduced the expression of pro-inflammatory cytokines in BEND cells induced by LPS. Meanwhile, immunofluorescence and western blotting results showed that let-7c significantly inhibited LPS-induced phosphorylation of NF-κB, thereby inhibiting downstream pro-inflammatory cytokine expression. Taken together, our results suggested that let-7c ameliorates LPS-induced endometritis by attenuating the expression of pro-inflammatory cytokines via inhibition of the activation of NF-κB.