Polyphenol Containing Sorghum Brans Exhibit an Anti-Cancer Effect in Apc Min/+ Mice Treated with Dextran Sodium Sulfate.

Colon cancer (CC) is considered a high-risk cancer in developed countries. Its etiology is correlated with a high consumption of red meat and low consumption of plant-based foods, including whole grains. Sorghum bran is rich in polyphenols. This study aimed to determine whether different high-phenolic sorghum brans suppress tumor formation in a genetic CC rodent model and elucidate mechanisms. Tissue culture experiments used colorectal cancer cell lines SW480, HCT-116 and Caco-2 and measured protein expression, and protein activity. The animal model used in this study was APC Min+/mouse model combined with dextram sodium sulfate. High phenolic sorghum bran extract treatment resulted in the inhibition of proliferation and induced apoptosis in CC cell lines. Treatment with high phenolic sorghum bran extracts repressed TNF-α-stimulated NF-κB transactivation and IGF-1-stimulated PI3K/AKT pathway via the downregulation of ß-catenin transactivation. Furthermore, high-phenolic sorghum bran extracts activated AMPK and autophagy. Feeding with high-phenolic sorghum bran for 6 weeks significantly suppressed tumor formation in an APC Min/+ dextran sodium sulfate promoted CC mouse model. Our data demonstrates the potential application of high-phenolic sorghum bran as a functional food for the prevention of CC.

High-polyphenol extracts from Sorghum bicolor attenuate replication of Legionella pneumophila within RAW 264.7 macrophages.

Polyphenols derived from a variety of plants have demonstrated antimicrobial activity against diverse microbial pathogens. Legionella pneumophila is an intracellular bacterial pathogen that opportunistically causes a severe inflammatory pneumonia in humans, called Legionnaires' Disease, via replication within macrophages. Previous studies demonstrated that tea polyphenols attenuate L. pneumophila intracellular replication within mouse macrophages via increased tumor necrosis factor (TNF) production. Sorghum bicolor is a sustainable cereal crop that thrives in arid environments and is well-suited to continued production in warming climates. Sorghum polyphenols have anticancer and antioxidant properties, but their antimicrobial activity has not been evaluated. Here, we investigated the impact of sorghum polyphenols on L. pneumophila intracellular replication within RAW 264.7 mouse macrophages. Sorghum high-polyphenol extract (HPE) attenuated L. pneumophila intracellular replication in a dose-dependent manner but did not impair either bacterial replication in rich media or macrophage viability. Moreover, HPE treatment enhanced both TNF and IL-6 secretion from L. pneumophila infected macrophages. Thus, polyphenols derived from sorghum enhance macrophage restriction of L. pneumophila, likely via increased pro-inflammatory cytokine production. This work reveals commonalities between plant polyphenol-mediated antimicrobial activity and provides a foundation for future evaluation of sorghum as an antimicrobial agent.