Impact of brown rice cultivated with deep-sea mineral fertiliser on colon cancer in vitro and in vivo studies

The suppressive effects of Naturaldream Brown Rice (NBR), cultivated with deep-sea mineral fertiliser in an azoxymethane (AOM)/ dextran sulphate sodium (DSS) mouse model of inflammatory colorectal cancer were explored by focusing on apoptosis, inflammatory responses and gut microbiota composition. NBR contains significantly higher levels of essential mineral contents and γ-oryzanol compared to conventional brown rice and organic brown rice, in addition to exhibiting robust antioxidant capacity and elevated total flavonoid and phenolic content. It also up-regulated cell cycle arrest factors, including p53 and p21 and pro-apoptotic markers such as Bax, Bak, Bim, Caspase 9 and Caspase 3. Concurrently, anti-apoptotic markers such as Bcl-2 and Bcl-xL were downregulated, enhancing cell death and cell cycle arrest. In the AOM/DSS mouse model, dietary intake of NBR improved mucosal integrity and reduced the expression of inflammatory cytokines (IL-1β, IL-6, IFN-γ) in serum, spleen cells and colon tissue. It also increased levels of the anti-inflammatory cytokines IL-10, induced cell cycle arrest, induced the expression of pro-apoptotic factors and inhibited the expression of anti-apoptotic factors in the colon. Furthermore, NBR altered the gut microbiota composition, elevating Lactobacillus and Faecalibacterium while decreasing Deferribacteraceae and Mucispirillum schaedleri. These results highlight the potential of NBR as a functional dietary source for colorectal cancer prevention through the enhancement of bioactive compounds, regulation of cellular and inflammatory responses and modulation of gut microbiota.