A combination of scGOS/lcFOS with Bifidobacterium breve M-16V protects suckling rats from rotavirus gastroenteritis.

PURPOSE: Rotavirus (RV) is the leading cause of severe diarrhoea among infants and young children, and although more standardized studies are needed, there is evidence that probiotics can help to fight against RV and other infectious and intestinal pathologies. On the other hand, the effects of prebiotics have not been properly addressed in the context of an RV infection. The aim of this study was to demonstrate a protective role for a specific scGOS/lcFOS 9:1 prebiotic mixture (PRE) separately, the probiotic Bifidobacterium breve M-16V (PRO) separately and the combination of the prebiotic mixture and the probiotic (synbiotic, SYN) in a suckling rat RV infection model. METHODS: The animals received the intervention from the 3rd to the 21st day of life by oral gavage. On day 7, RV was orally administered. Clinical parameters and immune response were evaluated. RESULTS: The intervention with the PRO reduced the incidence, severity and duration of the diarrhoea (p < 0.05). The PRE and SYN products improved clinical parameters as well, but a change in stool consistency induced by the PRE intervention hindered the observation of this effect. Both the PRE and the SYN, but not the PRO, significantly reduced viral shedding. All interventions modulated the specific antibody response in serum and intestinal washes at day 14 and 21 of life. CONCLUSIONS: A daily supplement of a scGOS/lcFOS 9:1 prebiotic mixture, Bifidobacterium breve M-16V or a combination of both is highly effective in modulating RV-induced diarrhoea in this preclinical model.

Cocoa intake attenuates oxidative stress associated with rat adjuvant arthritis.

Cocoa contains flavonoids with antioxidant properties. The aim of this study was to ascertain the effect of cocoa intake on oxidative stress associated with a model of chronic inflammation such as adjuvant arthritis. Female Wistar rats were fed with a 5% or 10% cocoa-enriched diet or were given p.o. a quercetin suspension every other day for 10 days. Arthritis was induced by a heat-killed Mycobacterium butyricum suspension. Reactive oxygen species (ROS) produced by macrophages, and splenic superoxide dismutase (total, cytoplasmic and mitochondrial) and catalase activities were determined. Clinically, joint swelling in arthritic rats was not reduced by antioxidants; however, the 5% cocoa diet and quercetin administration reduced ROS production. Moreover, the 5% cocoa diet normalized the activities of superoxide dismutase and catalase. In conclusion, a cocoa diet reduces the oxidative stress associated with a chronic inflammatory pathology, although it was not enough to attenuate joint swelling.

Effects of cooling and freezing storage on the stability of bioactive factors in human colostrum.

Breast milk constitutes the best form of newborn alimentation because of its nutritional and immunological properties. Banked human milk is stored at low temperature, which may produce losses of some bioactive milk components. During lactation, colostrum provides the requirements of the newborn during the first days of life. The aim of this study was to evaluate the effect of cooling storage at 4°C and freezing storage at -20°C and -80°C on bioactive factors in human colostrum. For this purpose, the content of IgA, growth factors such as epidermal growth factor, transforming growth factor (TGF)-ß1 and TGF-ß2, and some cytokines such as IL-6, IL-8, IL-10, and tumor necrosis factor (TNF)-α, and its type I receptor TNF-RI, were quantified. Some colostrum samples were stored for 6, 12, 24, and 48 h at 4°C and others were frozen at -20°C or -80°C for 6 and 12 mo. We quantified IgA, epidermal growth factor, TGF-ß1, and TGF-ß2 by indirect ELISA. Concentrations of IL-6, IL-10, and TNF-α cytokines, IL-8 chemokine, and TNF-RI were measured using the BD Cytometric Bead Array (BD Biosciences, Erembodegem, Belgium). Bioactive immunological factors measured in this study were retained in colostrum after cooling storage at 4°C for at least 48h, with the exception of IL-10. None of the initial bioactive factor concentrations was modified after 6 mo of freezing storage at either -20°C or -80°C. However, freezing storage of colostrum at -20°C and -80°C for 12 mo produced a decrease in the concentrations of IgA, IL-8, and TGF-ß1. In summary, colostrum can be stored at 4°C for up to 48 h or at -20°C or -80°C for at least 6 mo without losing its immunological properties. Future studies are necessary to develop quality assurance guidelines for the storage of colostrum in human milk banks, and to focus not only on the microbiological safety but also on the maintenance of the immunological properties of colostrum.

Maintenance of breast milk Immunoglobulin A after high-pressure processing.

Human milk is considered the optimal nutritional source for infants. Banked human milk is processed using low-temperature, long-time pasteurization, which assures microbial safety but involves heat denaturation of some desirable milk components such as IgA. High-pressure processing technology, the subject of the current research, has shown minimal destruction of food macromolecules. The objective of this study was to investigate the influence of pressure treatments on IgA content. Moreover, bacterial load was evaluated after pressure treatments. The effects of high-pressure processing on milk IgA content were compared with those of low-temperature, long-time pasteurization. Mature human milk samples were heat treated at 62.5 degrees C for 30min or pressure processed at 400, 500, or 600MPa for 5min at 12 degrees C. An indirect ELISA was used to measure IgA in human milk whey obtained after centrifugation at 800xg for 10min at 4 degrees C. All 3 high-pressure treatments were as effective as low-temperature, long-time pasteurization in reducing the bacterial population of the human milk samples studied. After human milk pressure processing at 400MPa, 100% of IgA content was preserved in milk whey, whereas only 72% was retained in pasteurized milk whey. The higher pressure conditions of 500 and 600MPa produced IgA retention of 87.9 and 69.3%, respectively. These results indicate that high-pressure processing at 400MPa for 5min at 12 degrees C maintains the immunological protective capacity associated with IgA antibodies. This preliminary study suggests that high-pressure processing may be a promising alternative to pasteurization in human milk banking.

[The bowel: a key component of the immune system]. / El intestino: pieza clave del sistema inmunitario.

The gut is constantly exposed to a high antigenic load coming from the diet and commensal bacteria. The Gut-Associated Lymphoid Tissue (GALT) constitutes the most extensive and complex part of the immune system and is capable of efficiently distinguishing invasive pathogens from innocuous antigens. The knowledge of its unique structure consisting on organised tissue, inductor of the immune response (Peyer's patches and mesenteric lymph nodes), and diffused tissue, effector of the immune response (intraepithelial lymphocytes and lamina propria lymphocytes), allow us to understand the development and regulation of the immune response in the gut and how this one can be extended to the rest of the organism.

Spleen lymphocyte function modulated by a cocoa-enriched diet.

Previous studies have shown the down-regulating in vitro effect of cocoa flavonoids on lymphocyte and macrophage activation. In the present paper, we report the capacity of a long-term rich cocoa diet to modulate macrophage cytokine secretion and lymphocyte function in young rats. Weaned rats received natural cocoa (4% or 10% food intake), containing 32 mg flavonoids/g, for 3 weeks. Spleen immune function was then evaluated through the analysis of lymphocyte composition, their proliferative response and their ability to secrete cytokines and Ig. In addition, the status of activated peritoneal macrophages was established through tumour necrosis factor (TNF)-alpha secretion. The richest cocoa diet (10%) caused a reduction of TNF-alpha secretion by peritoneal macrophages showing anti-inflammatory activity. Similarly, although a 10% cocoa diet increased lymphocyte proliferation rate, it down-regulated T helper 2 (Th2)-related cytokines and decreased Ig secretion. These changes were accompanied by an increase in spleen B cell proportion and a decrease in Th cell percentage. In summary, these results demonstrate the functional activity of a cocoa-high dosage in down-regulating the immune response that might be beneficial in hypersensitivity and autoimmunity.