Soy genistein administered in soluble chitosan microcapsules maintains antioxidant activity and limits intestinal inflammation.

We used water-soluble Chitosan obtained by Maillard reaction with glucosamine to microencapsulate soy genistein (Ge) and preserve its biological activity for oral administration. Release of Ge was pH dependent with a super Case II mechanism at pH 1.2 and an anomalous transport with non-Fickian kinetics at pH 6.8. Microencapsulated Ge retained its antioxidant properties in vitro and its daily administration to mice attenuated clinical signs of acute colitis, limited inflammatory reaction and reduced oxidative stress and tissue injury as well. Remarkably, after feeding microencapsulated Ge the production of IL-10 in colonic tissue was restored to levels of untreated controls. According to statistical multivariate analysis, this cytokine was the parameter with the highest influence on the inflammatory/oxidative status. Microencapsulation of Ge with derivatized Chitosan becomes an interesting alternative to develop therapeutic approaches for oxidative inflammatory diseases; our findings suggest that the soy isoflavone could be incorporated into any functional food for application in intestinal inflammation.

Migratory capacity and function of dendritic cells from mesenteric afferent lymph nodes after feeding a single dose of vitamin A.

Lamina propria dendritic cells (DCs) have a permanent turnover with constitutive migration to mesenteric lymph nodes and replenishment by progenitors. Luminal bacteria and dietary constituents provide key signals that endow DCs their unique properties in vivo. Taking into account that the intestinal immune system is greatly influenced by retinoids, we evaluated in B6 mice 3, 8, 16 and 24 h after feeding a single dose of vitamin A phenotype and function of cells present in mesenteric afferent lymph nodes as well as signals involved in migration. We studied the frequency of CD11c+MHC-II+CD103+CD86+ and RALDH+ DCs by flow cytometry, we determined CCL-21 and D6 levels in tissue homogenates by Western blot, and we co-cultured cells isolated from afferent lymphatics with sorted CD4+ lymphocytes to assess Foxp-3 induction and homing receptor expression. Sixteen hours after vitamin A administration, DCs isolated from afferent lymphatics were able to induce homing receptors and Foxp3 expression in CD4+ lymphocytes. Our results show that a single dose of vitamin A generated a stream of signals and amplified the tolerogenic activity of DCs migrating to lymphoid tissue.