tricin and Colitis

Ulcerative colitis is a subtype of inflammatory bowel disease, characterized by relapsing inflammation in the gastrointestinal tract with limited treatment options. Previous studies suggested that the natural compound tricin, a flavone isolated from rice bran, could suppress chemically-induced colitis in mice, while our recent study also demonstrated the anti-metastatic effect of tricin in colon tumor-bearing mice.. Here we further investigated the underlying mechanism of the inhibitory effects of tricin on lipopolysaccharides-activated macrophage RAW264.7 cells and explored the efficacy of tricin in acute colitis mouse model induced by 4.5% dextran sulfate sodium (DSS) for 7 days.. Tricin (75, 100, and 150 mg/kg) or the positive control drug sulfasalazine (200 mg/kg) were orally administered to mice for 7 days. Stool consistency scores, stool blood scores, and body weight were recorded daily. Disease activity index (DAI) was examined on day 7, and colon tissues were collected for biochemical analyses. The fecal microbiome of colitis mice after tricin treatment was characterized for the first time in this study using 16S rDNA amplicon sequencing.. Results showed that tricin (50 µM) remarkably reduced nitric oxide production in lipopolysaccharides-activated RAW264.7 cells and the anti-inflammatory activity of tricin was shown to act through the NF-κB pathway. Besides, tricin treatment at 150 mg/kg significantly reversed colon length reduction, reduced myeloperoxidase activities and DAI scores, as well as restored the elevated myeloid-derived suppressive cells population in acute colitis mice. The influence from DSS on gut microbiota, such as the increased population of Proteobacteria phylum and Ruminococcaceae family, was shown to be relieved after tricin treatment.. Our present study firstly demonstrated that tricin ameliorated acute colitis by improving colonic inflammation and modulating gut microbiota profile, which supports the potential therapeutic use of tricin for colitis treatment.

Topics: Animals; Anti-Inflammatory Agents; Colitis; Colitis, Ulcerative; Colon; Dextran Sulfate; Disease Models, Animal; Flavones; Flavonoids; Macrophages; Mice; NF-kappa B; RAW 264.7 Cells

Tricin present in rice and wheat exhibits antigrowth activity in several human cancer cell lines and anti-inflammatory potential. However, the chemopreventive activity has not yet been elucidated in preclinical animal models. This study was designed to determine whether dietary tricin exerts inflammation-associated colon carcinogenesis induced by azoxymethane (AOM) and dextran sulfate sodium (DSS) in mice. Male Crj: CD-1 mice were initiated with a single i.p. injection of AOM (10 mg/kg bw) and followed by a 1-week exposure to DSS (1.5%, w/v) in drinking water to induce colonic neoplasms. They were then given the experimental diet containing 50 or 250 ppm tricin. The experiment was terminated at week 18 to determine the chemopreventive efficacy of tricin. The effects of dietary tricin on the expression of several inflammatory cytokines, including tumor necrosis factor (TNF)-α, were also assayed. Feeding with tricin at both doses significantly inhibited the development of colonic tumors. Dietary tricin also significantly reduced the proliferation index and the numbers of mitoses/anaphase bridging of adenocarcinoma cells. Tricin feeding significantly suppressed the TNF-α expression in the normal appearing crypts. Our findings may suggest a potential use of tricin for clinical trials of colorectal cancer chemoprevention in the inflamed colon.

Topics: Animals; Anticarcinogenic Agents; Azoxymethane; Carcinogenesis; Colitis; Colon; Colonic Neoplasms; Cytokines; Dextran Sulfate; Diet; Flavonoids; Male; Mice; Tumor Necrosis Factor-alpha