Resumen del trabajo presentado a las III Jornadas Científicas CIAL Fórum, celebradas del 22 al 23 de noviembre de 2018 en el Instituto de Investigación en Ciencias de la Alimentación (CIAL)., La microbiota intestinal se ha señalado como un factor clave en la obesidad, dada su influencia en las funciones metabólicas e inmunológicas del hospedador. Desde el punto de vista de la composición estructural, la disbiosis de la microbiota intestinal asociada a obesidad, se ha relacionado con cambios en los ratios de los filos Firmicutes y Bacteroidetes. Estos cambios no han mostrado consistencia en estudios posteriores, si bien la obesidad parece estar relacionada con una menor diversidad bacteriana, una menor riqueza de genes y una alteración de las funciones metabólicas de la microbiota intestinal. Hoy en día, tanto el impacto de la composición y/o la funcionalidad de la microbiota como los mecanismos específicos de acción de esta microbiota en la obesidad, no están del todo claros. El principal objetivo de este trabajo ha sido determinar la importancia relativa de la composición taxonómica y/o funcional de la microbiota intestinal en la obesidad. La composición taxonómica de la microbiota fecal de individuos obesos (Ob) y normopeso (Np) se determinó por secuenciación masiva mediante la plataforma Illumina Seq. La amplificación del gen 16S rARN se realizó empleando como cebadores secuencias dirigidas hacia las regiones V3-V4 del gen. La caracterización funcional se determinó por medida de los ácidos grasos de cadena corta (AGCCs) por cromatografía líquida de alta eficacia (HPLC) y por medida de la concentración de amonio espectrofotométricamente. El análisis de los datos mostró que en el dominio Bacteria los filos más abundantes fueron Bacteroidetes (13%), Firmicutes (76%), Actinobacteria (10%) y Proteobacteria (1.8 %) sin encontrar diferencias significativas entre los individuos Ob y Np. El filo Verrumicrobia se encontró significativamente en mayor proporción en los individuos Np. A nivel de género, los grupos Collinsella, Alistipes, Clostridium sensu stricto, Clostridium XIVa, Romboutsia y Oscillibacter, entre otros, mostraron diferencias significativas entre ambos grupos de individuos. La diversidad bacteriana según el índice Chao1 fue significativamente mayor en los individuos Np a nivel de Filo y Familia. Respecto a la caracterización funcional, las muestras fecales de individuos Ob mostraron las mayores concentraciones de ácidos acético y butírico. Los resultados ponen de manifiesto que aún dentro de la gran variabilidad interindividual, la microbiota de individuos obesos se caracteriza por una mayor o menor presencia de determinados grupos microbianos y una mayor formación de determinados AGCCs respecto a la microbiota de individuos normopeso., Los autores agradecen la financiación otorgada por el Ministerio de Ciencia, Innovación y Universidades a través del proyecto AGL2016-75951-R., Peer reviewed

Resumen del trabajo presentado al IX Workshop on Probiotics, Prebiotics of the Spanish Society of Probiotics and Prebiotics (Sociedad Española de Probióticos y Prebióticos, SEPyP), celebrado en Zaragoza (España) del 15 al 16 de febrero de 2018., [Introduction] Ageing is characterized by an impairment of the homeostatic systems (nervous and immune systems) and consequently by a higher risk of morbidity and mortality. Nutritional intervention is one of the most used strategies to slow down this deterioration, and recently the supplementation with probiotics has been suggested as a possible way of improving these systems., [Objectives] This study evaluated the effects of the supplementation with Lactobacillus rhamnosus GG (LGG) on several behavioral and immune function parameters in a model of prematurely aging mice (PAM)., [Methods] Adult PAM and non-prematurely aging mice (NPAM), were divided into two groups, which received LGG (109 CFU/mice/day; lyophilized in skim milk and added to drink water) or skim milk without LGG (controls). After 2 weeks, mice were submitted to behavioural tests (anxiety-like behaviours and exploratory capacity). After this, and after an extra 2 week LGG supplementation, peritoneal leukocytes were collected and several immune functions (macrophage and lymphocyte chemotaxis, macrophage phagocytosis, natural killer cell activity and lymphoproliferative response to mitogens) were analyzed., [Results] The higher anxiety levels together with the lower exploratory activity observed in PAM compared with NPAM disappeared after LGG supplementation. Similar results were shown with PAM premature immunosenescence, and after 2 and 4 weeks of LGG intake an improvement of leukocyte functions was observed, with similar values to those found in NPAM. LGG counts reached 6 log DNA copy/g faeces in PAM and NPAM. However, there were no differences between the faecal microbiota
composition and metabolism of both groups (PAM and NPAM) at the starting of the assay and throughout 4 week LGG supplementation., [Conclusions] In conclusion, LGG ingestion improves nervous and immune functions in PAM. Since the parameters evaluated are health and ageing rate markers LGG could be useful for achieving a healthy longevity., This work was supported by FIS (PI15/01787) of Health Institute Carlos III – Regional Developing Aid European Funds (ISCIII-FEDER), MINEICO (AGL2016-75951-R, CDTI (ADAPTEA IDI-20150753) and CYTED (P916PTE0233)., Peer reviewed

Resumen del trabajo presentado al 10th Workshop on Probiotics and Prebiotics, celebrado en Las Palmas de Gran Canaria del 6 al 8 de febrero de 2019., [Background and Aims] The intestinal microbiota has been pointed out as a key factor in obesity, since it contributes to metabolic and inmunological homeostasis in the host. The dysbiosis of the gut microbiota linked to obesity has been related to a higher Firmicutes to Bacteroidetes ratio, a lower gene richness and an alteration of the metabolic functions of the gut microbiota. The main objective of this work was to outline the significance of the compositional and/or functional changes in the obese-associated intestinal microbiota., [Methods] The taxonomic composition of the fecal microbiota of obese (Ob) and normal weight (Np) individuals was determined by high-throughput sequencing analysis using the Illumina Seq platform.
Amplification of the 16S rRNA gene was carried out using as primers sequences directed towards the V3-V4 regions of the gene. Functional characterization was determined by measuring short chain fatty acids (SCFAs) by High Performance Liquid Chromatography (HPLC) and the ammonium concentration spectrophotometrically., [Results] Data analysis did not show significant differences between Ob and Np individuals in the dominant phyla Bacteroidetes (13%), Firmicutes (76%), Actinobacteria (10%) and Proteobacteria
(1.8%). Nevertheless, the proportion of Verrumicrobia was significantly higher in normal weight individuals (Np). At genus level, Collinsella, Alistipes, Clostridium, Clostridium XIVa, Romboutsia and Oscillibacter, among others, showed significant differences between both groups of individuals. Bacterial diversity according to the Chao1 index was significantly higher in Np individuals. Regarding the functional characterization, the fecal samples of Ob individuals showed the highest concentrations of acetic and butyric acids., [Conclusion] In spite of the great interindividual variability, the microbiota of obese individuals is characterized by a higher or lesser proportion of certain microbial groups and a higher formation of
SCFAs in relation to the microbiota of normal weight individuals., Finantial support by AGL2016-75951-R., Peer reviewed

Resumen del trabajo presentado al 10th Workshop on Probiotics and Prebiotics, celebrado en Las Palmas de Gran Canaria del 6 al 8 de febrero de 2019., [Background and Aims] Ageing is characterized by an impairment of the homeostatic (nervous and immune) systems and by changes in the intestinal microbiota. The objective of the study was to analyse differences in the gut microbiota and in several innate immune functions in old and prematurely ageing mice (PAM) when compared with adults, and the modulatory effects of supplementing with Lactobacillus rhamnosus GG., [Methods] Prematurely aging mice (PAM), old and adult mice (females ICR-CD1) were divided into two groups (N = 8-10), which received LGG (109 CFU/mice/day; lyophilized in skim milk and added to drink water) or skim milk without the probiotic LGG (controls). After 4 weeks of LGG supplementation, mice
were analysed for several innate immune parameters (chemotaxis, phagocytosis and natural killer activity). Faecal samples were collected for microbiota analysis at 0, 2 and 4 weeks of LGG
supplementation., [Results] Ageing in ICR-CD1 female mice was related with increase of Lactobacillus and Blautia coccoides/Eubacterium rectale and decrease of Akkermansia. LGG supplementation was related with changes in Bifidobacterium, Faecalibacterium and Ruminococcus counts. PAM and old mice showed lower values of the immune functions analysed than adult mice. After 4 weeks of LGG ingestion
all these functions improved, achieving values similar to those in adults., [Conclusion] L. rhamnosus GG can be considered a probiotic supplement useful for upgrading the immune system in ageing and, consequently, for reaching a healthy longevity., FIS (PI15/01787) of Health Institute Carlos III – Regional Developing Aid European Funds (ISCIII-FEDER), AGL2016-75951-R, CDTI (ADAPTEA IDI-20150753) and CYTED (P916PTE0233)., Peer reviewed