A Novel Mediation Strategy of DSS-Induced Colitis in Mice Based on an Iron-Enriched Probiotic and In Vivo Bioluminescence Tracing.

Iron deficiency (ID) caused by blood loss and/or reduced iron absorption is a serious problem influencing health in inflammatory bowel disease (IBD). However, traditional iron supplements may fail to meet no side effect demands for ID of IBD; thus, a new iron supplementation is highly desired to be developed. Herein, for the first time, probiotic Lactobacillus alimentarius NKU556 with an iron-enriching ability was screened from Chinese traditional fermented food then employed to intervene DSS-induced colitis with bioluminescence tracing in mice. As expected, oral administration with NKU556-Fe can remarkably enhance the expression of tight junction proteins and effectively reduce the pro-inflammatory cytokines as well as the oxidative stress on DSS-induced colitis in mice. Meanwhile, in comparison with the FeSO4 group, the intake of NKU556-Fe could suppress the expression of hepcidin derived from the liver and reduce the degradation of FPN1, thereby leading to the increase in the iron absorption of colitis in mice. According to the bioluminescence result, it was believed that the beneficial effects of oral administration with NKU556/NKU556-Fe on DSS-induced colitis in mice were hardly related to its metabolites but associated with its own function. These results concluded that the oral administration of NKU556-Fe could relieve colitis inflammation and increase iron absorption. In summary, current work not only proposed a novel mediation strategy for IBD but also offered some inspirations for future treatment of extraintestinal complications.

Dietary Supplementation of Foxtail Millet Ameliorates Colitis-Associated Colorectal Cancer in Mice via Activation of Gut Receptors and Suppression of the STAT3 Pathway.

Coarse cereal intake has been reported to be associated with reduced risk of colorectal cancer. However, evidence from intervention studies is absent and the molecular basis of this phenomenon remains largely unexplored. This study sought to investigate the effects of foxtail millet and rice, two common staple grains in Asia, on the progression of colitis-associated colorectal cancer (CAC) and define the mechanism involved. In total, 40 BALB/c mice were randomized into four groups. The Normal and azoxymethane/dextran sodium sulfate (AOM/DSS) groups were supplied with an AIN-93G diet, while the millet- and rice-treated groups were supplied with a modified AIN-93G diet. Compared to the AOM/DSS-induced CAC mice supplemented with rice, an increased survival rate, suppressed tumor burden, and reduced disease activity index were observed in the millet-treated group. The levels of IL-6 and IL-17 were decreased in the millet-treated group compared to both the AOM/DSS and AOM/DSS + rice groups. Millet treatment inhibited the phosphorylation of STAT3 and the related signaling proteins involved in cell proliferation, survival and angiogenesis. These beneficial effects were mediated by the activation of gut receptors AHR and GPCRs via the microbial metabolites (indole derivates and short-chain fatty acids) of foxtail millet. Moreover, millet-treatment increased the abundance of Bifidobacterium and Bacteroidales_S24-7 compared to the rice-treated mice. This study could help researchers to develop better dietary patterns that work against inflammatory bowel disease (IBD) and for CAC patients.