Functional anthocyanin-rich sausages diminish colorectal cancer in an animal model and reduce pro-inflammatory bacteria in the intestinal microbiota

Colorectal cancer is the fourth most common neoplasia in Europe, where it accounts for 28.2 new cases per 100,000 inhabitants. In an effort to decrease the incidence of this disease, various prevention measures are being studied, one of which are anthocyanin-rich foods. Anthocyanins are potent antioxidant flavonoids mainly found in flowers and colorful fruits and vegetables. These nutraceuticals have diverse biological functions once ingested, including immunomodulatory, anti-inflammatory and antitumor functions. In order to test the preventive effect of these flavonoids against colorectal cancer, an animal model (Rattus norvegicus F344) was developed. In this model two doses of azoxymethane (10 mg/kg) and two treatments with dextran sodium sulfate (DSS) were administered to the animals. For 20 weeks they were fed either control rat feed, control sausages, or functional sausages containing 0.1% (w/w) of anthocyanins from a mixture of dehydrated blackberries and strawberries. At the end of that period, the animals were sacrificed and their antioxidant plasma levels and digestive tract tissues were analyzed. The results revealed a statistically significant reduction in the number of colon tumors in the functional sausages cohort with respect to the control animals and an increase in the FRAP (ferric reducing ability of plasma) total antioxidant activity in that same cohort. Colon microbiota differences were also examined via metagenomics 16S ribosomal RNA (rRNA) sequencing, revealing a significant reduction in populations of the pro-inflammatory Bilophila wadsworthia. Therefore, the design of functional processed meat products, such as ones enriched with anthocyanins, may be an effective strategy for preventing inflammatory digestive diseases and colorectal cancer in human populations

Healthy effects of prebiotics and their metabolites against intestinal diseases and colorectal cancer

A specific group of plant and animal oligosaccharides does not suffer enzymatic digestion in the human upper intestinal tract, achieving the colon microbial ecosystem in intact form. The reason for that is their diverse glycosidic bond structure, in comparison with common energetic polysaccharides as starch or glycogen. In this complex ecosystem, these molecules serve as energy sources, via fermentation, of distinctive beneficial bacterial groups, mainly belonging to the Anaerostipes, Bifidobacterium, Coprococcus, Faecalibacterium, Lactobacillus, Roseburia and other genera. The main catabolic products of these fermentations are short-chain fatty acids (SCFA) as acetate, propionate and butyrate, which appear in high concentrations in the lumen around the colon mucosa. Acetate and propionate are associated to energetic purposes for enterocytes, hepatocytes and other cells. Butyrate is the preferred energy source for colonocytes where it controls their cell cycle; butyrate is able to induce cell cycle arrest and apoptosis in tumor colonocytes. These oligosaccharides that increase beneficial colon bacterial populations and induce SCFA production in this ecosystem are called prebiotics. Here, different sources and chemical structures for prebiotics are described, as well as their modulatory effect on the growth of specific probiotic bacterial groups in the colon, and how their fermentation renders diverse SCFA, with beneficial effects in gut healt

Galacto-oligosaccharides derived from lactulose protects against colorectal cancer development in an animal model

Workshop Probiotics and Prebiotics (9th, 2018, Zaragoza