“Cocoa and Chocolate: Science and Gastronomy”—The Second Annual Workshop of the Research Institute on Nutrition and Food Security (INSA): 9 November 2016

The Research Institute on Nutrition and Food Security at the University of Barcelona (INSA-UB) was founded in 2005 by twenty-two research groups from the Faculties of Pharmacy and Food Science; Biology; Chemistry; and Geography and History, as well as other UB-affiliated centers and hospitals. Most of the groups at the Institute are, or at least are part of, the research groups established by the Government of Catalonia. INSA-UB was founded to meet the current societal need for research, training and service provision in the sectors related to the agro-alimentary industry. Researchers at the Institute are experts in different fields of nutrition; food analysis and control; food safety and the study of the social and economic impact of food. The main objectives of the institute are to promote research in the fields in which it works; to encourage collaboration between researchers and the establishment of multidisciplinary teams; to promote participation in research programs and institutional administration, particularly in European research projects; to encourage the development of joint projects with companies in the sectors related to its scope; to make available all the social potential of the UB in this area, especially the training of technicians and specialists and provision of services; to promote the transfer of knowledge and the dissemination of research results between society and government; and to advise consumers, businesses and public authorities on nutrition, food safety and quality..

Flavonoids affect host-microbiota crosstalk through TLR modulation

Interaction between host cells and microbes is known as crosstalk. Among other mechanisms, this takes place when certain molecules of the micro-organisms are recognized by the toll-like receptors (TLRs) in the body cells, mainly in the intestinal epithelial cells and in the immune cells. TLRs belong to the pattern-recognition receptors and represent the first line of defense against pathogens, playing a pivotal role in both innate and adaptive immunity. Dysregulation in the activity of such receptors can lead to the development of chronic and severe inflammation as well as immunological disorders. Among components present in the diet, flavonoids have been suggested as antioxidant dietary factors able to modulate TLR-mediated signaling pathways. This review focuses on the molecular targets involved in the modulatory action of flavonoids on TLR-mediated signaling pathways, providing an overview of the mechanisms involved in such action. Particular flavonoids have been able to modify the composition of the microbiota, to modulate TLR gene and protein expression, and to regulate the downstream signaling molecules involved in the TLR pathway. These synergistic mechanisms suggest the role of some flavonoids in the preventive effect on certain chronic diseases

Cocoa and cocoa fibre differentially modulate IgA and IgM production at mucosal sites

Previous studies have shown that a 10% cocoa (C10) diet, containing polyphenols and fibre among others, modifies intestinal and systemic Ig production. The present study aimed at evaluating the impact of C10 on IgA and IgM production in the intestinal and extra-intestinal mucosal compartments, establishing the involvement of cocoa fibre (CF) in such effects. Mechanisms by which C10 intake may affect IgA synthesis in the salivary glands were also studied. To this effect, rats were fed either a standard diet, a diet containing C10, CF or inulin. Intestinal (the gut wash (GW), Peyer's patches (PP) and mesenteric lymph nodes (MLN)) and extra-intestinal (salivary glands) mucosal tissues and blood samples were collected for IgA and IgM quantification. The gene expressions of IgA production-and homing-related molecules were studied in the salivary glands. The C10 diet decreased intestinal IgA and IgM production. Although the CF diet decreased the GW IgA concentration, it increased PP, MLN and serum IgA concentrations. Both the C10 and the CF diets produced a down-regulatory effect on IgA secretion in the extra-intestinal tissues. The C10 diet interacted with the mechanisms involved in IgA synthesis, whereas the CF showed particular effects on the homing and transcytosis of IgA across the salivary glands. Overall, CF was able to up-regulate IgA production in the intestinal-inductor compartments, whereas it down-regulated its production at the mucosal-effector ones. Further studies must be directed to ascertain the mechanisms involved in the effect of particular cocoa components on gut-associated lymphoid tissue

Ludificació en Immunonutrició: tres estratègies per jugar amb els nutrients i el sistema immunitari

Amb la finalitat d'obtenir un aprenentatge més significatiu dels continguts de l'assignatura d'Immunonutrició, s'han portat a terme 3 activitats diferents per tal de ludificar el desenvolupament de les classes. Segons l'opinió dels estudiants les tres actuacions han estat altament satisfactòries. A més, el fet de poder obtenir el reforç addicional en la qualificació final de l'assignatura ha demostrat ser un motor per a la implicació dels estudiants en la dinàmica de classe

Intensive Training and Sex Influence Intestinal Microbiota Composition: A Preclinical Approach

Lifestyle, including regular physical activity and dietary habits, influences microbiota composition. Although some studies have demonstrated changes in microbiota composition due to moderate or high intensity training in athletes, the relationship between physical activity and changes in the intestinal bacteria is still a matter of discussion. In addition, as most studies are performed on males, the role of sexual dimorphism deserves to be explored. Therefore, the aim of this preliminary study was to ascertain the influence of an intensive training and the rat's sex on caecal microbiota composition. For this purpose, female and male 4-week-old Wistar rats were submitted to a 4-week running training program. At the end, caecal samples were collected immediately after performing an exhaustion test to characterize the microbiota composition by 16S rRNA sequencing technique. Parallel groups of female and male sedentary (SED) rats (age matched) were included. The results showed that young female rats had a higher ability to run than males but no sex- or training-associated changes were observed on microbiota diversity and richness indexes among groups. However, the Actinobacteria, Bifidobacteriaceae and Bifidobacterium spp. proportions were significantly higher in male than in female rats when comparing SED groups (p <0.05), whose proportions in males were decreased by the training program (p < 0.05 vs. SED). On the contrary, female SED rats showed a higher proportion of Odoribacteraceae (belonging to Bacteroidetes), Clostridiaceae and Eubacteriaceae (both Firmicutes) than in the respective male group (p < 0.05), although Eubacteriaceae proportion decreased by running (p < 0.05 vs. SED). However, training increased the proportion of the Paraeggerthella genus (Actinobacteria) in female rats with respect to its sedentary counterpart (p < 0.05). Overall, caecal microbiota composition is modified by intensive training in young rats but there are also sex-based differences that should be considered for interventional studies

Does Flavonoid Consumption Improve Exercise Performance? Is It Related to Changes in the Immune System and Inflammatory Biomarkers? A Systematic Review of Clinical Studies since 2005

Flavonoids are attracting increasing attention due to their antioxidant, cardioprotective, and immunomodulatory properties. Nevertheless, little is known about their role in exercise performance in association with immune function. This systematic review firstly aimed to shed light on the ergogenic potential of flavonoids. A search strategy was run using SCOPUS database. The returned studies were screened by prespecified eligibility criteria, including intervention lasting at least one week and performance objectively quantified, among others. Fifty-one studies (54 articles) met the inclusion criteria, involving 1288 human subjects, either physically untrained or trained. Secondly, we aimed to associate these studies with the immune system status. Seventeen of the selected studies (18 articles) assessed changes in the immune system. The overall percentage of studies reporting an improved exercise performance following flavonoid supplementation was 37%, the proportion being 25% when considering quercetin, 28% for flavanol-enriched extracts, and 54% for anthocyanins enriched extracts. From the studies reporting an enhanced performance, only two, using anthocyanin supplements, focused on the immune system and found certain anti-inflammatory effects of these flavonoids. These results suggest that flavonoids, especially anthocyanins, may exert beneficial effects for athletes' performances, although further studies are encouraged to establish the optimal dosage and to clarify their impact on immune status

Alterations in the innate immune system due to exhausting exercise in intensively trained rats

It is known that intensive physical activity alters the immune system's functionality. However, the influence of the intensity and duration of exercise needs to be studied in more depth. We aimed to establish the changes in the innate immune response induced by two programmes of intensive training in rats compared to sedentary rats. A short training programme included 2 weeks of intensive training, ending with an exhaustion test (short training with exhaustion, S-TE). A second training programme comprised 5-week training including two exhaustion tests and three trainings per week. In this case, immune status was assessed before (T), immediately after (TE) and 24 h after (TE24) an additional final exhaustion test. Biomarkers such as phagocytic activity, macrophage cytokine and reactive oxygen species (ROS) production, and natural killer (NK) cell activity were quantified. S-TE was not enough to induce changes in the assessed innate immunity biomarkers. However, the second training was accompanied by a decrease in the phagocytic activity, changes in the pattern of cytokine secretion and ROS production by macrophages and reduced NK cell proportion but increased NK cytotoxic activity. In conclusion, a 5-week intense training programme, but not a shorter training, induced alterations in the innate immune system functionality

Association between urinary metabolic profile and the intestinal effects of cocoa in rats

The aim of this study was to elucidate the relationship between the urinary metabolic fingerprint and the effects of cocoa and cocoa fibre on body weight, hormone metabolism, intestinal immunity and microbiota composition. To this effect, Wistar rats were fed, for 3 weeks, a diet containing 10 % cocoa (C10) or two other diets with same the proportion of fibres: one based on cocoa fibre (CF) and another containing inulin as a reference (REF) diet. The rats' 24 h urine samples were analysed by an untargeted 1H NMR spectroscopy-based metabonomic approach. Concentrations of faecal IgA and plasma metabolic hormones were also quantified. The C10 diet decreased the intestinal IgA, plasma glucagon-like peptide-1 and glucagon concentrations and increased ghrelin levels compared with those in the REF group. Clear differences were observed between the metabolic profiles from the C10 group and those from the CF group. Urine metabolites derived from cocoa correlated with the cocoa effects on body weight, immunity and the gut microbiota. Overall, cocoa intake alters the host and bacterial metabolism concerning energy and amino acid pathways, leading to a metabolic signature that can be used as a marker for consumption. This metabolic profile correlates with body weight, metabolic hormones, intestinal immunity and microbiota composition.</p

Alteractions in the mucosal immune system by a chronic exhausting exercise in Wistar rats

Exhausting exercise can disturb immune and gastrointestinal functions. Nevertheless, the impact of it on mucosal-associated lymphoid tissue has not been studied in depth. Here, we aim to establish the effects of an intensive training and exhausting exercise on the mucosal immunity of rats and to approach the mechanisms involved. Rats were submitted to a high-intensity training consisting of running in a treadmill 5 days per week for 5 weeks, involving 2 weekly exhaustion tests. At the end, samples were obtained before (T), immediately after (TE) and 24 h after (TE24) an additional final exhaustion test. The training programme reduced the salivary production of immunoglobulin A, impaired the tight junction proteins' gene expression and modified the mesenteric lymph node lymphocyte composition and function, increasing the ratio between Tαβ+ and B lymphocytes, reducing their proliferation capacity and enhancing their interferon-γ secretion. As a consequence of the final exhaustion test, the caecal IgA content increased, while it impaired the gut zonula occludens expression and enhanced the interleukin-2 and interferon-γ secretion. Our results indicate that intensive training for 5 weeks followed or not by an additional exhaustion disrupts the mucosalassociated lymphoid tissue and the intestinal epithelial barrier integrity in rats