Preclinical immunomodulation by the probiotic Bifidobacterium breve M-16V in early life

This study aimed to investigate the effect of supplementation with the probiotic Bifidobacterium breve M-16V on the maturation of the intestinal and circulating immune system during suckling. In order to achieve this purpose, neonatal Lewis rats were supplemented with the probiotic strain from the 6th to the 18th day of life. The animals were weighed during the study, and faecal samples were obtained and evaluated daily. On day 19, rats were euthanized and intestinal wash samples, mesenteric lymph node (MLN) cells, splenocytes and intraepithelial lymphocytes (IEL) were obtained. The probiotic supplementation in early life did not modify the growth curve and did not enhance the systemic immune maturation. However, it increased the proportion of cells bearing TLR4 in the MLN and IEL, and enhanced the percentage of the integrin αEβ7+ and CD62L+ cells in the MLN and that of the integrin αEβ7+ cells in the IEL, suggesting an enhancement of the homing process of naïve T lymphocytes to the MLN, and the retention of activated lymphocytes in the intraepithelial compartment. Interestingly, B. breve M-16V enhanced the intestinal IgA synthesis. In conclusion, supplementation with the probiotic strain B. breve M-16V during suckling improves the development of mucosal immunity in early lif

Rotavirus double infection model to study preventive dietary interventions

Rotaviruses are the main cause of acute diarrhea among young children worldwide with an increased frequency of reinfection. Several life style factors, such as dietary components, may influence such processes by affecting the outcome of the first rotavirus infection and therefore having a beneficial impact on the anti-rotavirus immune responses during any subsequent reinfections. The aim of this research was to develop a double-infection model in rat that mimics real-life clinical scenarios and would be useful in testing whether nutritional compounds can modulate the rotavirus-associated disease and immune response. Three experimental designs and a preventive dietary-like intervention were conducted in order to achieve a differential response in the double-infected animals compared to the single-infected ones and to study the potential action of a modulatory agent in early life. Diarrhea was only observed after the first infection, with a reduction of fecal pH and fever. After the second infection an increase in body temperature was also found. The immune response against the second infection was regulated by the preventive effect of the dietary-like intervention during the first infection in terms of specific antibodies and DTH. A rotavirus-double-infection rat model has been developed and is suitable for use in future preventive dietary intervention studies. KEYWORDS: diarrhea; double-infection; model; rat; rotaviru

Effect of cocoa's theobromine on intestinal microbiota of rats

SCOPE: To establish the role of cocoa theobromine on gut microbiota composition and fermentation products after cocoa consumption in rats. METHODS AND RESULTS: Lewis rats were fed either a standard diet (RF diet), a diet containing 10% cocoa (CC diet) or a diet including 0.25% theobromine (TB diet) for 15 days. Gut microbiota (fluorescence in situ hybridization coupled to flow cytometry and metagenomics analysis), SCFA and IgA-coated bacteria were analyzed in fecal samples. CC and TB diets induced lower counts of E. coli whereas TB diet led to lower counts of Bifidobacterium spp., Streptococcus spp. and Clostridium histolyticum-C. perfingens group compared to RF diet. Metagenomics analysis also revealed a different microbiota pattern among the studied groups. The SCFA content was higher after both CC and TB diets, which was mainly due to enhanced butyric acid production. Furthermore, both diets decreased the proportion of IgA-coated bacteria. CONCLUSION: Cocoa's theobromine plays a relevant role in some effects related to cocoa intake, such as the lower proportion of IgA-coated bacteria. Moreover, theobromine modifies gut microbiota although other cocoa compounds could also act on intestinal bacteria, attenuating or enhancing the theobromine effects

Preventive effect of a synbiotic combination of galacto- and fructooligosaccharides mixture with Bifidobacterium breve M-16V in a model of multiple rotavirus infections

Rotavirus (RV) causes morbidity and mortality among infants worldwide, and there is evidence that probiotics and prebiotics can have a positive influence against infective processes such as that due to RV. The aim of this study was to evidence a preventive role of one prebiotic mixture (of short-chain galactooligosaccharide/long-chain fructooligosaccharide), the probiotic Bifidobacterium breve M-16V and the combination of the prebiotic and the probiotic, as a synbiotic, in a suckling rat double-RV infection model. Hyperimmune bovine colostrum was used as protection control. The first infection was induced with RV SA11 and the second one with EDIM. Clinical variables and immune response were evaluated after both infections. Dietary interventions ameliorated clinical symptoms after the first infection. The prebiotic and the synbiotic significantly reduced viral shedding after the first infection, but all the interventions showed higher viral load than in the RV group after the second infection. All interventions modulated ex vivo antibody and cytokine production, gut wash cytokine levels and small intestine gene expression after both infections. In conclusion, a daily supplement of the products tested in this preclinical model is highly effective in preventing RV-induced diarrhea but allowing the boost of the early immune response for a future immune response against reinfection, suggesting that these components may be potential agents for modulating RV infection in infants. Keywords: prebiotic, probiotic, synbiotic, rotavirus, FOS, GOS, Bifidobacterium brev

Prevention of Rotavirus Diarrhea in Suckling Rats by a Specific Fermented Milk Concentrate with Prebiotic Mixture

Several microbial modulatory concepts, such as certain probiotics and prebiotics, confer protection against gastrointestinal infections, among which is acute diarrhea caused by the rotavirus (RV). Other microbiota modulators, such as postbiotics, produced during fermentation, might also have the potential to counteract RV infection. In light of this, a fermented milk, made by using Bifidobacterium breve C50 (BbC50) and Streptococcus thermophilus 065 (St065) with a prebiotic mixture¿short chain galactooligosaccharides/long chain fructooligosaccharides (scGOS/lcFOS 9:1)¿with potential to impact the intestinal microbiota composition was tested. An RV infected rat model was used to evaluate the amelioration of the infectious process and the improvement of the immune response induced by the fermented milk with prebiotic mixture. The dietary intervention caused a reduction in the clinical symptoms of diarrhea, such as severity and incidence. Furthermore, a modulation of the immune response was observed, which might enhance the reduction of the associated diarrhea. In addition, the fermented milk with prebiotic mixture was able to bind the virus and reduce its clearance. In conclusion, the postbiotic components in the fermented milk in combination with the prebiotics used here showed protective properties against RV infection

Immunomodulatory role of probiotics in early life

Podeu consultar el llibre complet a: http://hdl.handle.net/2445/12071

Acció moduladora de prebiòtics i probiòtics sobre la infecció per rotavirus en un model de rates lactants

[cat] El rotavirus (RV) és el principal causant de diarrea greu en nens menors de cinc anys i, encara que es necessiten més estudis estandarditzats, hi ha evidència de que els probiòtics poden ajudar a lluitar contra el RV i contra altres patologies infeccioses i intestinals. Sobre aquesta base, l'objectiu de la present tesi va ser el d’avaluar l'efecte protector de productes relacionats amb els probiòtics i els prebiòtics contra les infeccions per rotavirus, utilitzant models experimentals en rata lactant. Per aconseguir aquest objectiu, es va utilitzar un model d’infecció simple per RV ja existent, amb algunes noves variables. D'altra banda, es va desenvolupar un nou model de doble infecció per rotavirus en rates. Diverses variables immunològiques van demostrar que és adequat per a la realització d'estudis intervencionals, i sembla que les accions moduladores sobre la primera infecció tenen una influència sobre la resposta immunitària desenvolupada enfront a una segona infecció per RV. Això s'ha demostrat amb l'administració d’un calostre boví hiperimmune contra el RV (HBC) durant la primera infecció. Pel que fa a la suplementació amb la soca probiòtica Bifidobacterium breve M-16V durant la lactància, s’ha observat que millora el desenvolupament de la immunitat de la mucosa en rates per mitjà de la modulació de l'expressió de TLR, la millora del procés de reclutament dels limfòcits T verges als GLM i la retenció dels limfòcits activats al compartiment intraepitelial, així com la potenciació de la síntesi d’IgA intestinal. D'altra banda, modula la infecció i la reinfecció per RV en el model d’infecció simple i doble, respectivament, alleugerint les manifestacions clíniques durant la primera infecció, però permetent a l'hoste elaborar la pròpia resposta immunitària, que l'ajudarà a controlar una segona infecció. En quant a la suplementació prebiòtica durant la lactància en rates, la barreja prebiòtica scGOS/lcFOS 9:1 (Immunofortis), tot i presentar un efecte directe sobre la consistència de les femtes, ha mostrat efectes beneficiosos contra la infecció per RV i ha modulat la reinfecció en el model de doble infecció, mostrant una important acció immunomoduladora. Aquests efectes han estat comparables als del prebiòtic Bimuno® GOS. Com a simbiòtic, quan s’ha avaluat en combinació amb el probiòtic B. breve M-16V, s’ha mostrat molt eficaç en la modulació de la diarrea induïda per RV, així com en la modulació de la resposta immunitària i de la reinfecció per RV en el model preclínic de doble infecció. Per contra, la combinació d’Immunofortis® amb oligosacàrids acídics derivats de pectina (pAOS) no ha potenciat el seu efecte preventiu sobre el model de gastroenteritis per RV en rata. D'altra banda, la suplementació amb un postbiòtic (una llet fermentada per B. breve i Streptococcus thermophilus) durant la lactància en rates, ha estat capaç de prevenir gairebé totes les manifestacions derivades de la diarrea induïda per RV, mentre que també ha modulat la resposta immunitària anti-RV. L’addició d’Immunofortis® a aquest postbiòtic no ha mostrat efectes clars de sinèrgia. Com a conclusió general, tots els productes estudiats, essent el probiòtic i el postbiòtic els més eficaços, han mostrat efectes beneficiosos sobre la gastroenteritis induïda per RV en el model de rata lactant, modulant les variables clíniques i resposta immunitària en primeres etapes de vida. Així i tot, calen més estudis per comprendre millor el seu mecanisme d'acció i per a ser considerats per a la seva inclusió en preparats per a lactants o suplements, com estratègies per a la protecció contra la diarrea induïda per RV en nens.[eng] Rotavirus (RV) is the leading cause of severe diarrhoea among infants and young children and there is evidence that probiotics can help to fight against RV infection. The aim of the present thesis was to evaluate the protective effect of probiotics, prebiotics and other related products against RV infections using the suckling rat as experimental model. To achieve this objective, an updated model of simple RV infection and a new RV double-infection model in rat were used. Regarding the probiotic effect, the supplementation with Bifidobacterium breve M-16V improved the development of mucosal immunity in early-life rats. Moreover, it attenuated RV infection and reinfection by ameliorating diarrhoea during first infection but allowing the host to elaborate its own immune response, which seems to help control the second infection. Regarding the prebiotic effect, scGOS/lcFOS 9:1 (Immunofortis) ameliorated RV infection in the single-infection model and modulated reinfection in the double RV infection model, showing a high immunomodulatory action. Its effect was comparable to that of the prebiotic Bimuno GOS. A synbiotic combining the scGOS/lcFOS prebiotic with the probiotic Bifidobacterium breve M-16V, was highly effective in modulating RV-induced diarrhoea as well as modulating immune response and RV reinfection in the double-infection preclinical model. Conversely, the combination of Immunofortis with pectin-derived acidic oligosaccharides (pAOS) did not potentiate its preventive effect. The postbiotic supplementation with a Bifidobacterium breve and Streptococcus thermophilus-fermented formula, and its combination with scGOS/lcFOS were able to prevent almost all features derived from the RV-induced diarrhoea and they also modulated the anti-RV immune response. Overall, all tested products showed beneficial effects on the RV-induced gastroenteritis in the neonatal rat model, modulating clinical biomarkers and immune system responses early in life, with the probiotic and the postbiotic being the most effective. Further studies are needed in order to better understand their mechanism of action and for them to be considered for inclusion in infant formulas or supplements as strategies for protecting against human RV-induced diarrhoea in children

Preclinical Immunomodulation by the Probiotic Bifidobacterium breve M-16V in Early Life.

This study aimed to investigate the effect of supplementation with the probiotic Bifidobacterium breve M-16V on the maturation of the intestinal and circulating immune system during suckling. In order to achieve this purpose, neonatal Lewis rats were supplemented with the probiotic strain from the 6th to the 18th day of life. The animals were weighed during the study, and faecal samples were obtained and evaluated daily. On day 19, rats were euthanized and intestinal wash samples, mesenteric lymph node (MLN) cells, splenocytes and intraepithelial lymphocytes (IEL) were obtained. The probiotic supplementation in early life did not modify the growth curve and did not enhance the systemic immune maturation. However, it increased the proportion of cells bearing TLR4 in the MLN and IEL, and enhanced the percentage of the integrin αEβ7+ and CD62L+ cells in the MLN and that of the integrin αEβ7+ cells in the IEL, suggesting an enhancement of the homing process of naïve T lymphocytes to the MLN, and the retention of activated lymphocytes in the intraepithelial compartment. Interestingly, B. breve M-16V enhanced the intestinal IgA synthesis. In conclusion, supplementation with the probiotic strain B. breve M-16V during suckling improves the development of mucosal immunity in early life

Preventive Effect of a Synbiotic Combination of Galacto- and Fructooligosaccharides Mixture With Bifidobacterium breve M-16V in a Model of Multiple Rotavirus Infections

Rotavirus (RV) causes morbidity and mortality among infants worldwide, and there is evidence that probiotics and prebiotics can have a positive influence against infective processes such as that due to RV. The aim of this study was to evidence a preventive role of one prebiotic mixture (of short-chain galactooligosaccharide/long-chain fructooligosaccharide), the probiotic Bifidobacterium breve M-16V and the combination of the prebiotic and the probiotic, as a synbiotic, in a suckling rat double-RV infection model. Hyperimmune bovine colostrum was used as protection control. The first infection was induced with RV SA11 and the second one with EDIM. Clinical variables and immune response were evaluated after both infections. Dietary interventions ameliorated clinical symptoms after the first infection. The prebiotic and the synbiotic significantly reduced viral shedding after the first infection, but all the interventions showed higher viral load than in the RV group after the second infection. All interventions modulated ex vivo antibody and cytokine production, gut wash cytokine levels and small intestine gene expression after both infections. In conclusion, a daily supplement of the products tested in this preclinical model is highly effective in preventing RV-induced diarrhea but allowing the boost of the early immune response for a future immune response against reinfection, suggesting that these components may be potential agents for modulating RV infection in infants

αE integrin/CD62L molecular pattern in the total lymphocytes of the spleen, mesenteric lymph nodes (MLN) and intraepithelial lymphocytes (IEL).

<p>Representative histograms for the reference (REF) and probiotic (PRO) groups are shown. In each quadrant the mean ± SEM (n = 8 animals/group) is included. Statistical differences: *p<0.05 <i>vs</i>. REF.</p