Clostridium butyricum and Its Culture Supernatant Alleviate the Escherichia coli-Induced Endometritis in Mice

SIMPLE SUMMARY: This study evaluated the therapeutic effect of Clostridium butyricum and its culture supernatant on Escherichia coli-induced endometritis in mice. We infused E. coli into the uterine cavity of mice and induced endometritis. After 48 hours, Clostridium butyricum or its culture supernatant was infused into the uterine cavity of mice. After 48 hours, physiological indicators, uterine morphology, histopathology and uterine bacterial load were examined. The results showed that both Clostridium butyricum and its culture supernatant relieved uterine inflammation. In addition, we evaluated the reproductive performance of mice treated with Clostridium butyricum and its culture supernatant, and the results showed that they improved the reproductive performance of mice with endometritis. Finally, we have investigated the effect of Clostridium butyricum and its culture supernatant on the NF-κB signaling pathway, and the results show that they inhibit the activation of NF-κB signaling pathway. In conclusion, Clostridium butyricum and its culture supernatant have a potential therapeutic effect on Escherichia coli-induced endometritis. ABSTRACT: Endometritis is a disease with a high incidence in dairy cows and causes great economic loss to milk production. This study examined the therapeutic effects of Clostridium butyricum and its culture supernatant on Escherichia coli-induced endometritis in mice. The results showed that Clostridium butyricum and its culture supernatant effectively suppressed inflammatory responses of uterine tissues, such as uterine morphological changes, pathological damage, and the production of inflammatory cytokines. Clostridium butyricum and its culture supernatant significantly decreased uterine microbial loads. In addition, Clostridium butyricum and its culture supernatant restored reproduction outcomes in Escherichia coli-induced endometritis mice. Western blot analysis showed that Clostridium butyricum and its culture supernatant suppressed the NF-κB signaling pathway. Therefore, the anti-inflammatory mechanism of Clostridium butyricum and its culture supernatant may occur through the anti-bacterial activity and regulation of the expression of NF-κB in the uterus. The anti-inflammatory effect of the culture supernatant of C. butyricum was slightly better than that of viable C. butyricum. Therefore, our experimental results showed that Clostridium butyricum culture supernatant may be an effective drug for treating endometritis.