P044 Milk derived exosomes has a therapeutic effect on experimental colitis

R. Golan-Gerstl1, N. Koroukhov1, Y. Elbaum Shiff2, I. Shilo1, S. Reif2

1Department of Pediatrics, Hadassah-Hebrew University Medical Center, Jerusalem, Israel, 2School of Nutritional Sciences, Hebrew University of Jerusalem, Jerusalem, Israel

Background

Inflammatory bowel disease (IBD) is a complex disorder that results from a dysregulated immune response in the gut. Emerging therapy for IBD treatment is mainly focused on regulation of the immune response. Exosomes are nanovesicle packing different molecules such as miRNAs that transfer their cargo to recipient cells. We and others found that mammalian milk contain high concentration of exosomes (milk-derived exosomes, MDE) carrying beneficial miRNAs such as miRNA-148. Furthermore, MDE are taken up by different cell type such as intestinal epithelial cells, modify target gene expression, promote proliferation and differentiation of colon epithelial cells. The aim of this study is to explore the therapeutic effect of MDE on colitis.

Methods

We used gavage administration of MDE labelled with DiR dye to track their localisation patterns in vivo. The therapeutic effect of MDE on colitis was study in mice model of SDS induced colitis, colon length, histopathological scoring grade, cytokine expression, stool consistency and miRNA expression were analysed.

Results

Imaging of mouse that have receive labelled MDE revealed an accumulation of fluorescent signal in the intestine. Moreover, fluorescent signal in the intestine and liver is time dependent. MDE reduced the histopathological scoring grade from 5.83 ± 1.47 to 0.6 ± 0.6, p < 0.05. The length of the colon of MDE-treated animals was 7.9 ± 0.19 in comparison to 6.92 ± 0.3 p < 0.05 of the untreated. The weight loss as a result of the colitis was reverted in MDE-treated mice. Likewise, MDE treatment reduced IL-6, TNF-α and caveolin expression from 3.83 to 0.78, 1.59 to 0.86 and 3.52 to 1.1, respectively. Highly expressed miRNAs (miRNA-320, 375, Let-7a and 6073) were found to be more abundant in colon of MDE treatment mice compared with the untreated.

Conclusion

This study demonstrated that MDE have a therapeutic effect on colitis in vivo. Proving the effect of MDE on colitis will have implications for the potential of adding MDE as a therapeutic nutrient to be included in the formulas for IBD patients.