Elderly people intestinal microbiota as a target for probiotic functional food intervention

Objective: PROBIOSENIOR is a research project that aims to evaluate the effect of a probiotic functional food based-diet on the reduction of low-grade inflammation, by improving the intestinal barrier function and the composition of the intestinal microbiota, in healthy senior subjects. It is an in vivo, double-blind, randomized, placebo-controlled study. Preliminary results obtained from a small boarding home will be presented here. Methods: Eleven subjects have been selected following the inclusion criteria and a baseline characterization of the physiological, nutritional and lifestyle parameters have been performed sampling questionnaires and blood, urine, faecal samples. To analyse the biodiversity of gut microbiota, DNA extraction and Real-Time PCR were used detecting and quantifying the bacterial levels, while gas-chromatography coupled to flame ionization detection was used for Short Chain Fatty Acids quantification. Results: Questionnaires collected data about lifestyle, eating habits, pathological and psychological anamnesis of the recruited subjects. The microbial analysis showed the amount and variability of the bacterial groups quantified (Lactobacillus spp., Enterobacteriaceae, Bacteroides-Prevotella-Porphyromonas spp., Bifidobacterium spp., Staphylococcus spp., Cl. coccoides-Eu. rectale group, expressed in log CFU/g of faeces). SCFAs were also quantified for each senior subject. Conclusions: These preliminary results showed a correlation between dietary/lifestyle habits of this small community of elderly people and their gut microbial status. This is only a first piece of the PROBIOSENIOR project that will monitor a greater senior population following the changes made by the probiotic dietary intervention.