title: Involvement of intracellular signaling in the IL-1β inhibitory effect on fructose intestinal absorption.
abstract: A variety of bacteria and their excreted/secreted products having direct effects on epithelial ion transport and permeability and the release of cytokines during bacterial infection may impact directly on epithelial function. Interleukin-1β (IL-1β) is a pleiotropic cytokine that affects the intestinal absorption of nutrients. The aim of this work was to study the intracellular signaling pathways involved in the inhibitory effect of IL-1β on D-fructose intestinal transport in rabbit jejunum and Caco-2 cells. The results show that the cytokine inhibitory effect was completely reversed in presence of proteasome or PKC selective inhibitors in IL-1β treated rabbits. In addition, the activation of PI3K abolished the IL-1β effect. Likewise, these results were confirmed in Caco-2 cells. In addition, p-PI3K expression was increased by IL-1β-treatment whereas the expression of p-PKCα was not significantly affected. In summary, the results suggest that IL-1β could regulate the activation of pPKCα 73, pPI3K 55, and NF-kB proteins. These events could exert an inhibitory effect on fructose intestinal absorption by a modification of GLUT5 insertion to brush-border membrane and/or the functional transporter activity. This effect is independent of hormonal milieu and nervous stimuli.
authors.affiliation: Physiology Unit, Department of Pharmacology and Physiology, University of Zaragoza, Zaragoza, Spain; CIBER de Fisiopatología de la Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III (ISCIII), Spain.
authors.forename: María J
authors.initials: MJ
authors.lastname: Rodríguez-Yoldi
authors.forename: Sonia
authors.initials: S
authors.lastname: Gascón
authors.forename: Cristina
authors.initials: C
authors.lastname: Barranquero
authors.forename: Alberto
authors.initials: A
authors.lastname: García-Barrios
authors.forename: Jesús
authors.initials: J
authors.lastname: Osada
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D018938:Caco-2 Cells; D005632:Fructose / Q000378:metabolism*; D051296:Glucose Transporter Type 5 / Q000378:metabolism; D006801:Humans; D053583:Interleukin-1beta / Q000037:antagonists & inhibitors* / Q000378:metabolism; D007408:Intestinal Absorption / Q000187:drug effects* / Q000502:physiology; D007413:Intestinal Mucosa / Q000187:drug effects; D008297:Male; D016328:NF-kappa B / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D011817:Rabbits; D015398:Signal Transduction / Q000187:drug effects*
chemical_list: D051296:Glucose Transporter Type 5; D053583:Interleukin-1beta; D016328:NF-kappa B; D005632:Fructose; D019869:Phosphatidylinositol 3-Kinases