Mango (Mangifera indica L.) polyphenols reduce IL-8, GRO, and GM-SCF plasma levels and increase Lactobacillus species in a pilot study in patients with inflammatory bowel disease

Inflammatory bowel disease (IBD) characterized by chronic intestinal inflammation and intestinal microbial dysbiosis present a major risk factor in the development of colorectal cancer. Previously, dietary polyphenols from mango (Mangifera indica L.) such as gallotannins and gallic acid have been shown to mitigate intestinal inflammation and carcinogenesis, as well as modulate intestinal microbial composition. To further translate findings from preclinical models, we hypothesized that mango polyphenols possess anti-inflammatory and microbiome-modulatory activities and may improve symptoms of IBD, reduce biomarkers for inflammation and modulate the intestinal microbiome when administered as an adjuvant treatment in combination with conventional medications in patients with mild to moderate IBD. In this study, ten participants received a daily dose of 200–400 g of mango pulp for 8 weeks (NCT02227602). Mango intake significantly improved the primary outcome Simple Clinical Colitis Activity Index (SCCAI) score and decreased the plasma levels of pro-inflammatory cytokines including interleukin-8 (IL-8), growth-regulated oncogene (GRO) and granulocyte macrophage colony-stimulating factor (GM-CSF) by 16.2% (P = .0475), 25.0% (P = .0375) and 28.6% (P = .0485), all factors related to neutrophil-induced inflammation, respectively. Mango intake beneficially altered fecal microbial composition by significantly increasing the abundance of Lactobacillus spp., Lactobacillus plantarum, Lactobacillus reuteri and Lactobacillus lactis, which was accompanied by increased fecal butyric acid production. Therefore, enriching diet with mango fruits or potentially other gallotannin-rich foods seems to be a promising adjuvant therapy combined with conventional medications in the management of IBD via reducing biomarkers of inflammation and modulating the intestinal microbiota.