The inhibition of colon cancer development by black rice bran on BALB/C Mice

Black rice bran (BRB) is well-known for its high antioxidant activity and its pivotal role in preventing colon cancer. The present study aims to investigate the effects of BRB administration on BALB/C mice induced with azoxymethane (AOM) and dextran sodium sulphate (DSS). The 24 mice were divided into three groups: the group induced by colon cancer (C+), the group induced by cancer and given the BRB diet (C+BRB), and the normal group (C−). Both the C− and C+ groups were given a standard AIN-93 M diet containing cellulose fiber. After 16 weeks, the mice were anesthetized, and the colonic tissue was identified for nodule distribution, histopathological observation, and mRNA expression analysis of proliferating cell nuclear antigen (PCNA), caspase-3, and caspase-8 genes using qRT PCR technique. Nodule distribution in the C+BRB group showed a significant decrease compared to the C+ group, with 1.65 ± 0.71 nodule/cm2 vs. 5.73 ± 2.93 nodule/cm². Then, the colon weight was significantly decreased in the C+BRB group, at 0.19 ± 0.04 (g) compared to 0.25 ± 0.03 (g) in the C+ group. Also, the BRB diet in the C+BRB group significantly decreased PCNA mRNA expression compared to the C+ group, with values of 0.58 ± 0.09-fold change vs. 5.22 ± 0.80-fold change. Conversely, increased the mRNA expression of caspase-3 (0.91 ± 0.20-fold change vs. 0.36 ± 0.15-fold change) and caspase-8 (0.51 ± 0.18-fold change vs. 0.13 ± 0.31-fold change). In conclusion, administration of BRB inhibited the rate of cancer development by suppressing cancer cell proliferation and inducing apoptosis.