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Proteolytic starter cultures with intrinsic immunomodulatory activities are desirably features for the development of functional foods, which would significantly reduce the cost of their production (one-strain starter) having an additional beneficial effect on the host. In this work, Lactobacillus delbrueckii strains were selected according to their ability to efficiently hydrolyse ß-casein and to modulate the immune system. Among 36 strains evaluated, the highest proteolytic activities were found for L. delbrueckii subsp. lactis CRL581 and L. delbrueckii subsp. bulgaricus CRL656. The immunomodulatory effect of both strains and their ß-casein hydrolysates (CRL581 and CRL656 hydrolysates, respectively) were studied in a murine model. Balb/c mice were fed lactobacilli or their hydrolysates for three days. One day after the last lactobacilli or hydrolysate treatments, mice were challenged with the Toll-like receptor 3 (TLR3) agonist poly(I:C) by intraperitoneal injection. Before and after poly(I:C) challenge the phagocytic and microbicidal activity of peritoneal macrophages, intestinal immunoglobulin A (IgA), cytokine profile, and histological analysis of the intestine were analysed. L. delbrueckii subsp. lactis CRL581 significantly increased the activation of peritoneal macrophages as well as the levels of intestinal IgA, interleukin (IL)-10 and interferon (IFN)-γ when compared to untreated controls. In addition, the CRL581 strain was able to significantly reduce the intestinal inflammatory damage triggered by TLR3 activation. L. delbrueckii CRL581 increased the levels of IL-10, IFN-γ and IFN-ß, and reduced tumour necrosis factor alpha and IL-6 concentrations in the intestine of poly(I:C)-challenged mice. No immunomodulatory effects were observed for the CRL656 strain or for the CRL581 or CRL656 hydrolysates. The results of this work show that the technologically relevant and high proteolytic strain L. delbrueckii CRL581 is able to beneficially modulate the intestinal innate antiviral immune response. Although further studies with the CRL581 strain are required to corroborate and deepen its immunological effects, this bacterium is an interesting alternative for the development of new functional foods with antiviral capabilities.

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Previously, we reported that the non-viable immunomodulatory Bifidobacterium infantis MCC12 and Bifidobacterium breve MCC1274 strains (paraimmunobiotic bifidobacteria) were able to increase the protection against rotavirus infection in bovine intestinal epithelial (BIE) cells. In order to gain insight into the influence of paraimmunobiotic bifidobacteria on the innate antiviral immune response of BIE cells, their effect on the transcriptomic response triggered by Toll-like receptor 3 (TLR3) activation was investigated. By using microarray technology and qPCR analysis, we obtained a global overview of the immune genes involved in the innate antiviral immune response in BIE cells. Activation of TLR3 by poly(I:C) in BIE cells significantly increased the expression of interferon (IFN)-α and IFN-ß, several interferon-stimulated genes, cytokines, and chemokines. It was also observed that both paraimmunobiotic bifidobacteria differently modulated immune genes expression in poly(I:C)-challenged BIE cells. Most notable changes were found in genes involved in antiviral defence (IFN-ß, MX1, OAS1X, MDA5, TLR3, STAT2, STAT3), cytokines (interleukin (IL)-6), and chemokines (CCL2, CXCL2, CXCL6) that were significantly increased in bifidobacteria-treated BIE cells. B. infantis MCC12 and B. breve MCC1274 showed quantitative and qualitative differences in their capacities to modulate the innate antiviral immune response in BIE cells. B. breve MCC1274 was more efficient than the MCC12 strain to improve the production of type I IFNs and antiviral factors, an effect that could be related to its higher ability to protect against rotavirus replication in BIE cells. Interestingly, B. infantis MCC12 showed a remarkable anti-inflammatory effect. The MCC12 strain was more efficient to reduce the expression of inflammatory cytokines and chemokines (IL-16, IL-20, CX3CL1) when compared with B. breve MCC1274. These results provided valuable information for the deeper understanding of the antiviral immune response of intestinal epithelial cells as well as the host-paraimmunobiotic interaction in the bovine host.

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Helicobacter pylori infection is associated with important gastric pathologies. An aggressive proinflammatory immune response is generated in the gastric tissue infected with H. pylori, resulting in gastritis and a series of morphological changes that increase the susceptibility to cancer development. Probiotics could present an alternative solution to prevent or decrease H. pylori infection. Among them, the use of immunomodulatory lactic acid bacteria represents a promising option to reduce the severity of chronic inflammatory-mediated tissue damage and to improve protective immunity against H. pylori. We previously isolated Lactobacillus fermentum UCO-979C from human gastric tissue and demonstrated its capacity to reduce adhesion of H. pylori to human gastric epithelial cells (AGS cells). In this work, the ability of L. fermentum UCO-979C to modulate immune response in AGS cells and PMA phorbol 12-myristate 13-acetate (PMA)-differentiated THP-1 (human monocytic leukaemia) macrophages in response to H. pylori infection was evaluated. We demonstrated that the UCO-979C strain is able to differentially modulate the cytokine response of gastric epithelial cells and macrophages after H. pylori infection. Of note, L. fermentum UCO-979C was able to significantly reduce the production of inflammatory cytokines and chemokines in AGS and THP-1 cells as well as increase the levels of immunoregulatory cytokines, indicating a remarkable anti-inflammatory effect. These findings strongly support the probiotic potential of L. fermentum UCO-979C and provide evidence of its beneficial effects against the inflammatory damage induced by H. pylori infection. Although our findings should be proven in appropriate experiments in vivo, in both H. pylori infection animal models and human trials, the results of the present work provide a scientific rationale for the use of L. fermentum UCO-979C to prevent or reduce H. pylori-induced gastric inflammation in humans.

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El Retardo Mental en los niños es una condición anormal del desarrollo del Sistema Nervioso, cuyo origen es usualmente multifactorial pero aun insuficientemente estudiada, lo cual repercute en la efectividad de acciones de intervención preventiva. Con el objetivo de tratar de establecer una relación entre las insuficiencias nutricionales de las madres embarazadas y la aparición de retardo mental no explicado por otras causas en sus hijos, se diseñó una investigación cualitativa con un diseño tipo descriptivo, cualitativo etnográfico por categorías, correlacional, parcialmente retrospectivo-prospectivo, desarrollado en el Centro de Recuperación Nutricional Infantil Integral “Dr. Pastor Oropeza”. La muestra estuvo constituida por 10 binomios madre-hijo, aplicándose una metodología de encuesta con la Encuesta “Identificación de riesgos nutricionales y peligros de discapacidad prenatal” a las madres y la Guía Portage de Educación Preescolar a los niños, para identificar posibles retardos en las áreas de socialización, lenguaje, motricidad, cognición y autoayuda. Los resultados fueron: se ejecutaron 918 evaluaciones a los 10 niños incluidos según los ítems sugeridos en la Guía Portage, encontrando que el 84.20 por ciento no logró superar lo explorado y de manera mas severa el área de lenguaje y cognitivo con 90 por ciento de fallas. En cuanto a las madres, se encontró que el 84 por ciento no poseían conocimientos ni practicas saludables en nutrición durante el embarazo, atribuibles no solo a las madres sino también al equipo de salud que las hubo de atender durante los controles de embarazo. La casi coincidencia de los dos porcentajes: 84.20 y 84, sugieren una posible asociación (RR=1) (OR=7), cuya fundamentación es ampliamente discutida en el texto de trabajo, analizada a la luz de las numerosas evidencias obtenidas en la bibliografía disponible.

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