title: Effect of a cocoa diet on the small intestine and gut-associated lymphoid tissue composition in an oral sensitization model in rats.
abstract: Previous studies have attributed to the cocoa powder the capacity to attenuate the immune response in a rat oral sensitization model. To gain a better understanding of cocoa-induced mechanisms at small intestinal level, 3-week-old female Lewis rats were fed either a standard diet or a diet containing 10% cocoa for 4 weeks with or without concomitant oral sensitization with ovalbumin (OVA). Thereafter, we evaluated the lymphocyte composition of the Peyer's patches (PPL), small intestine epithelium (IEL) and lamina propria (LPL). Likewise, gene expression of several immune molecules was quantified in the small intestine. Moreover, histological samples were used to evaluate the proportion of goblet cells, IgA+ cells and granzyme+cells as well. In cocoa-fed animals, we identified a five-time reduction in the percentage of IgA+ cells in intestinal tissue together with a decreased proportion of TLR4+ IEL. Analyzing the lymphocyte composition, almost a double proportion of TCRγδ+cells and an increase of NK cell percentage in PPL and IEL were found. In addition, a rise in CD25+, CD103+ and CD62L- cell proportions was observed in CD4+ PPL from cocoa-fed animals, along with a decrease in gene expression of CD11b, CD11c and IL-10. These results suggest that changes in PPL and IEL composition and in the gene expression induced by the cocoa diet could be involved, among other mechanisms, on its tolerogenic effect.
authors.affiliation: Section of Physiology, Department of Biochemistry and Physiology, Faculty of Pharmacy and Food Science, University of Barcelona, 08028, Barcelona, Spain; Nutrition and Food Safety Research Institute (INSA-UB), 08921 Santa Coloma de Gramenet, Spain; Institute of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, A-1090, Vienna, Austria. Electronic address: marionacamps@ub.edu.
authors.forename: Mariona
authors.initials: M
authors.lastname: Camps-Bossacoma
authors.affiliation: Section of Physiology, Department of Biochemistry and Physiology, Faculty of Pharmacy and Food Science, University of Barcelona, 08028, Barcelona, Spain; Nutrition and Food Safety Research Institute (INSA-UB), 08921 Santa Coloma de Gramenet, Spain. Electronic address: franciscoperez@ub.edu.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Pérez-Cano
authors.affiliation: Section of Physiology, Department of Biochemistry and Physiology, Faculty of Pharmacy and Food Science, University of Barcelona, 08028, Barcelona, Spain; Nutrition and Food Safety Research Institute (INSA-UB), 08921 Santa Coloma de Gramenet, Spain. Electronic address: angelsfranch@ub.edu.
authors.forename: Àngels
authors.initials: À
authors.lastname: Franch
authors.affiliation: Institute of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, A-1090, Vienna, Austria. Electronic address: eva.untersmayr@meduniwien.ac.at.
authors.forename: Eva
authors.initials: E
authors.lastname: Untersmayr
authors.affiliation: Section of Physiology, Department of Biochemistry and Physiology, Faculty of Pharmacy and Food Science, University of Barcelona, 08028, Barcelona, Spain; Nutrition and Food Safety Research Institute (INSA-UB), 08921 Santa Coloma de Gramenet, Spain. Electronic address: margaridacastell@ub.edu.
authors.forename: Margarida
authors.initials: M
authors.lastname: Castell
mesh_terms: D000284:Administration, Oral; D000818:Animals; D002099:Cacao; D004195:Disease Models, Animal; D004848:Epithelium / Q000473:pathology; D005260:Female; D005512:Food Hypersensitivity / Q000178:diet therapy* / Q000473:pathology; D007070:Immunoglobulin A / Q000378:metabolism; D007421:Intestine, Small / Q000378:metabolism / Q000473:pathology*; D008214:Lymphocytes / Q000473:pathology; D008221:Lymphoid Tissue / Q000473:pathology*; D010047:Ovalbumin / Q000008:administration & dosage / Q000009:adverse effects; D010581:Peyer's Patches / Q000473:pathology; D011917:Rats, Inbred Lew; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000378:metabolism; D051197:Toll-Like Receptor 4 / Q000378:metabolism
chemical_list: D007070:Immunoglobulin A; D016692:Receptors, Antigen, T-Cell, gamma-delta; C495347:Tlr4 protein, rat; D051197:Toll-Like Receptor 4; D010047:Ovalbumin
keywords: Cholera toxin; Cocoa; Ovalbumin; TCRγδ+cells; Tolerance