Resíduo do processamento da groselha negra (Ribes nigum L.) como um novo ingrediente funcional: percepções sobre a bioacessibilidade e bioatividade na carcinogênese colorretal

Abstract

Since dietary factors are considered responsible for the high risk of colon cancer, the present study aimed to evaluate the potential effect of blackcurrant press cake in cell culture and in animal models (Wistar rats) induced for colorectal cancer. For this, the blackcurrant press cake underwent an in vitro extraction and digestion process, chemical analysis and its respective extracts were tested in a cell culture model, to evaluate parameters such as cytotoxicity and antioxidant activity. Likewise, crude blackcurrant press cake was offered to the rats, incorporated into the feed, and parameters were evaluated in relation to the inflammatory process, oxidative stress, aberrant crypt foci in the colon, colon morphology and modulation of the intestinal microbiota. The results obtained indicated that the chemical analysis of the blackcurrant press cake showed a higher anthocyanin content after in vitro gastrointestinal digestion and, consequently, a higher antioxidant potential. When tested in cell culture, blackcurrant press cake extracts protected against ROS production and lipid peroxidation in vitro and showed no cytotoxicity in the tested cell lines. In colon cancer-induced (CRC) rats, consumption of the highest dosage of blackcurrant press cake increased pro-inflammatory parameters, as well as the expression of anti-apoptotic cytokines, in addition to accentuating the onset and progression of colon cancer, demonstrated through the analysis of aberrant crypt foci and histomorphological analyses. Furthermore, the cellular antioxidant defense could not adequately protect against the large amounts of ROS produced. Finally, fecal analysis showed that blackcurrant press cake alters the composition and function of the gut microbiome. Together, these evidences suggest that the anthocyanins present in blackcurrant press cake in highest dosages can act as a pro-oxidant compound, accentuating the inflammatory environment and the progression of CRC.