Ulcerative colitis (UC) is a non-specific inflammatory bowel illness characterized by intestinal mucosal barrier degradation, inflammation, oxidative damage, and gut microbiota imbalances. Rosa roxburghii Tratt Fruit extract (RRTE) was extracted from Rosa roxburghii Tratt fruit, exhibiting an excellent prevention effect against UC; RRTE could prevent the damage of DSS-induced human normal colonic epithelial (NCM 460) cells, especially in cell viability and morphology, and oxidative damage. Additionally, in UC mice, RRTE could limit the intestinal mucosal barrier by increasing the expression of intestinal tight junction proteins and mucin, reducing inflammation and oxidative damage in colon tissue. More importantly, RRTE can increase the abundance of beneficial bacteria to regulate gut microbiota such as Ruminococcus, Turicibacter, and Parabacteroides, and reduce the abundance of harmful bacteria such as Staphylococcus and Shigella. Furthermore, transcriptomics of colonic mucosal findings point out that the beneficial effect of RRTE on UC could be attributed to the modulation of inflammatory responses such as the IL-17 and TNF signaling pathways. The qPCR results confirm that RRTE did involve the regulation of several genes in the IL-17 signaling pathway. In conclusion, RRTE could prevent DSS-induced damage both in vitro and in vivo.
Okra flowers are a good source of polysaccharides and flavonoids, with biological activities of anti-inflammatory action and modulation of the gut microbiota. Previously, we reported that flavonoid-rich extracts from okra flowers (AFE) presented effective anti-colorectal cancer (CRC) activity in CRC cells as well as xenograft models, but their role in colitis-associated cancer (CAC) is unidentified. In this study, we aimed to evaluate the effects of AFE and APE (polysaccharides extracted from okra flowers) on the CAC symptoms of azoxymethane (AOM)/dextran sodium sulfate (DSS)-intervened mice. The results showed that APE and AFE exert potent efficacy in inhibiting colitis and colorectal tumorigenesis stimulated by AOM/DSS, characterized by decreased colonic shortening, DAI score, and tumor numbers. Compared with the control group, APE/AFE alleviated the microbiota dysbiosis driven by AOM/DSS. In addition, AFE elicited its anticancer activity through regulation of NFκB/IL-6/Stat3, JAK2/Stat3, MAPKs, PI3K/AKT, and Wnt/β-catenin signal transductions in AOM/DSS mice, which was consistent with a vitro model of CT26 cells, while APE treatment exhibited anticancer activity through regulation of Nrf2/IL-6, MAPKs, PI3K/AKT, and Wnt/β-catenin signal transductions in the AOM/DSS mouse model. Collectively, our studies revealed, for the first time, that flavonoids and polysaccharides from okra flowers possess the ability to attenuate colitis and colorectal tumorigenesis, with them having great potential to become promising candidates against CRC.