Abstract:

The study aims to investigate the mechanism of endometrial inflammatory in cows with Escherichia coli, and lay a foundation for screening drugs that act on key signaling pathway targets. In this study, bovine endometrial epithelial cells (bEEC) were obtained and purified from cow uterus with primarily cultured tissue explant and trypsin. The cells by 30 μg/mL lipopolysaccharide (LPS) stimulating 12 h was screened out, which was used as the bEEC inflammatory injury model in vitro. IL-1β, IL-8, IL-6 and TNF-α mRNA levels of bEEC induced in 2 h, 6 h, 9 h and 12 h by LPS were detected with RT-PCR, and NF-κB and MAPKs related proteins in LPS-bEEC cells were detected by Western-blot. The results showed that IL-1β, IL-8, IL-6 and TNF-α mRNA were highly expressed in 2 h, 6 h, 9 h and 12 h caused by 30 μg/mL LPS (P<0.01). LPS could up-regulate the phosphorylation levels of P38, ERK and JNK which were related with MAPKs (P<0.01), and promote the degradation of IκBα which was the inhibitory protein of NF-κB (P<0.05). MAPKs and NF-кB signaling pathway of bEEC could be activated by LPS, and then a large number of inflammatory mediators were released, causing inflammation damage of the cells.

Key words: lipopolysaccharide, cow endometritis, epithelial cells, cytokines, MAPKs