Purpose: In this study, we showed the beneficial effects of donkey milk (DM) on inflammatory damages, endogenous antimicrobial peptides levels and fecal microbiota profile in a mice model of Crohn's disease. Nowadays, new strategies of microbiome manipulations are on the light involving specific diets to induce and/or to maintain clinical remission. Interest of DM is explained by its high levels of antimicrobial peptides which confer it anti-inflammatory properties.
Methods: C57BL/6 mice were orally administered with or without indomethacin for 5 days and co-treated with vehicle, DM or heated DM during 7 days. Intestinal length and macroscopic damage scores (MDSs) were determined; ileal samples were taken off for microscopic damage (MD), lysozyme immunostaining and mRNA α-defensin assessments. Ileal luminal content and fecal pellets were collected for lysozyme enzymatic activity and lipocalin-2 (LCN-2) evaluations. Fecal microbiota profiles were compared using a real-time quantitative PCR-based analysis.
Results: Administration of indomethacin caused an ileitis in mice characterized by (1) a decrease in body weight and intestinal length, (2) a significant increase in MDS, MD and LCN-2, (3) a reduction in both α-defensin mRNA expression and lysozyme levels in Paneth's cells reflected by a decrease in lysozyme activity in feces, and (4) a global change in relative abundance of targeted microbial communities. DM treatment significantly reduced almost of all these ileitis damages, whereas heated DM has no impact on ileitis.
Conclusions: DM consumption exerts anti-inflammatory properties in mice by restoring the endogenous levels of antimicrobial peptides which contribute in turn to reduce microbiota imbalance.
Keywords: Antimicrobial peptides; Crohn’s disease; Donkey milk; Dysbiosis; Ileitis.