Cranberry extract promotes anti‐inflammatory activity of Lactobacillus plantarum on HT‐29 human colon cancer cells (647.35)

Probiotics modulate gastrointestinal inflammation by converting non‐digestible dietary nutrients into metabolites for colon epithelial health. Cranberry proanthocyanidins (PACs) can prevent urinary tract infection; however, the role of PACs as a prebiotic in the gastrointestinal tract is unclear. We studied the prebiotic effect of cranberry extract in promoting the anti‐inflammatory activity of Lactobacillus plantarum (Lp) on HT‐29 human colon cancer cells. Lp was incubated overnight with HT‐29 cells at a 10:1 ratio in the presence of 0, 0.01, or 0.1 mg PAC/mL cranberry extract. The presence of Lp decreased ( P <0.05) IL‐1β, IL‐2, IL‐6, and TNF‐α production by HT‐29 cells, indicating anti‐inflammatory activity. Addition of cranberry extract to HT‐29+Lp co‐cultures decreased ( P <0.05) NF‐κB and IL‐1β gene expression in HT‐29 cells in a dose‐dependent manner when compared to Lp alone. Cranberry extract (0.1 mg PAC/mL) downregulated ( P <0.05) COX‐2, and upregulated ( P <0.05) IL‐10 expression and superoxide dismutase activity in HT‐29 cells compared to Lp alone, suggesting enhanced antioxidant activity. Cranberry extract at 0.01 mg PAC/mL decreased ( P <0.05) while at 0.1 mg PAC/mL increased ( P <0.05) IL‐4 and IL‐8 production compared to Lp alone. Therefore, cranberry extract has a potential anti‐inflammatory and anti‐oxidant role in promoting Lp probiotic activity on HT‐29 cells. Grant Funding Source : Supported by ARC, Washington State University