Bacillus coagulant HYI (BC-HYI) Alleviates LPS-Elicited Oxidative Stress by Engaging the Nrf2/HO-1 Signaling Pathway and Regulates Gut Macrobiotics in Laying Chickens

In the current study, Bacillus coagulants had a role in combating oxidative stress by inhibiting the growth of intestinal pathogens. However, there are few studies on reducing the mechanisms of oxidative stress. Therefore, this study aimed to explore the effects and underlying mechanisms of B. coagulant HYI (BC-HYI) treatment on growth and intestinal functions in laying chickens under LPS-induced oxidative stress. The in vivo experimental group included five groups of laying chicks: normal control, LPS group, B6 group, B7 group and B8 group. The test consisted of six repetitions in each group, with six animals in each repetition. In the in vitro experiment, an LPS-induced oxidative stress model of chicken fibroblast DF-1 cells was established, and the DF-1 cells were divided into control group, LPS-treated group, B5 group, B6 group and B7 group. On the one hand, we found that BC-HYI can inhibit pathological changes in some intestinal tissues. On the other hand, BC-HYI supplementation has a dual effect on the gut microbiota, promoting the proliferation of beneficial microbes such as Barbarella, Lactobacillus, and Antibacterial while maintaining symbiotic balance. The abundance of Barbarella, Bactericide, and Cloistral was significantly different between the LPS group and the BC-HYI group (p < 0.01). Moreover, compared with the LPS group, BC-HYI significantly decreased reactive oxygen species levels and prevented cell apoptosis (p < 0.01). It used to prevent oxidative stress by activating the Nrf2-ARE/HO-1 signaling pathway, enhancing the scavenging of free radicals, and reducing oxidative damage. BC-HYI alleviated oxidative stress in laying chickens by modulating the gut microbiota and activating the Nrf2-ARE/HO-1 signaling pathway. In summary, laying chickens and cell experiments indicate that BC-HYI supplementation can improve the enzyme function of antioxidants, regulate intestinal barrier function and activate the Nrf2-ARE/HO-1 signaling pathway to regulate intestinal barrier function.