title: Retinoid levels influence enterohemorrhagic Escherichia coli infection and Shiga toxin 2 susceptibility in mice.
abstract: Enterohemorrhagic Escherichia coli (EHEC) is a food-borne pathogen that produces Shiga toxin (Stx) and causes hemorrhagic colitis. Under some circumstances, Stx produced within the intestinal tract enters the bloodstream, leading to systemic complications that may cause the potentially fatal hemolytic-uremic syndrome. Although retinoids like vitamin A (VA) and retinoic acid (RA) are beneficial to gut integrity and the immune system, the effect of VA supplementation on gastrointestinal infections of different etiologies has been controversial. Thus, the aim of this work was to study the influence of different VA status on the outcome of an EHEC intestinal infection in mice. We report that VA deficiency worsened the intestinal damage during EHEC infection but simultaneously improved survival. Since death is associated mainly with Stx toxicity, Stx was intravenously inoculated to analyze whether retinoid levels affect Stx susceptibility. Interestingly, while VA-deficient (VA-D) mice were resistant to a lethal dose of Stx2, RA-supplemented mice were more susceptible to it. Given that peripheral blood polymorphonuclear cells (PMNs) are known to potentiate Stx2 toxicity, we studied the influence of retinoid levels on the absolute number and function of PMNs. We found that VA-D mice had decreased PMN numbers and a diminished capacity to produce reactive oxygen species, while RA supplementation had the opposite effect. These results are in line with the well-known function of retinoids in maintaining the homeostasis of the gut but support the idea that they have a proinflammatory effect by acting, in part, on the PMN population.
authors.affiliation: Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental (IMEX) (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Cabrera
authors.affiliation: Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental (IMEX) (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina.
authors.forename: Romina J
authors.initials: RJ
authors.lastname: Fernández-Brando
authors.affiliation: Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental (IMEX) (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina.
authors.forename: María Jimena
authors.initials: MJ
authors.lastname: Abrey-Recalde
authors.affiliation: Servicio de Fisiopatogenia, Instituto Nacional de Enfermedades Infecciosas-ANLIS Dr. Carlos Malbrán, Buenos Aires, Argentina.
authors.forename: Ariela
authors.initials: A
authors.lastname: Baschkier
authors.affiliation: Laboratorio de Neurofisiología, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Alipio
authors.initials: A
authors.lastname: Pinto
authors.affiliation: Laboratorio de Neurofisiología, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Jorge
authors.initials: J
authors.lastname: Goldstein
authors.affiliation: Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Elsa
authors.initials: E
authors.lastname: Zotta
authors.affiliation: Departamento de Patología, Centro de Estudios Oncológicos, Academia Nacional de Medicina, Buenos Aires, Argentina.
authors.forename: Roberto
authors.initials: R
authors.lastname: Meiss
authors.affiliation: Servicio de Fisiopatogenia, Instituto Nacional de Enfermedades Infecciosas-ANLIS Dr. Carlos Malbrán, Buenos Aires, Argentina.
authors.forename: Marta
authors.initials: M
authors.lastname: Rivas
authors.affiliation: Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental (IMEX) (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina mspalermo@hematologia.anm.edu.ar.
authors.forename: Marina S
authors.initials: MS
authors.lastname: Palermo
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D054324:Enterohemorrhagic Escherichia coli / Q000378:metabolism*; D004927:Escherichia coli Infections / Q000378:metabolism* / Q000382:microbiology; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D017382:Reactive Oxygen Species / Q000378:metabolism; D012176:Retinoids / Q000378:metabolism*; D022641:Shiga Toxin 2 / Q000378:metabolism*; D014801:Vitamin A / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species; D012176:Retinoids; D022641:Shiga Toxin 2; D014801:Vitamin A