Evaluation of the Effects of the Tritordeum-Based Diet Compared to the Low-FODMAPs Diet on the Fecal Metabolome of IBS-D Patients: A Preliminary Investigation.

Since irritable bowel syndrome (IBS)-a common gastrointestinal (GI) disorder-still lacks effective therapy, a nutritional approach may represent a practical alternative. Different reports demonstrated that a low-fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) diet (LFD) reduces symptoms in IBS with diarrhea (IBS-D) patients, also inducing beneficial pathophysiological and biochemical modifications. More recently, diets with alternative cereals having a different gluten composition, such as tritordeum, have also been considered (TBD). We investigated the impact of TBD and LFD on the fecal metabolome composition in 38 IBS-D patients randomly allocated to the two diets for 12 weeks. Summarily, at baseline, the profile of fecal volatile organic compounds (VOCs) of IBS-D patients was not significantly different in the two groups. After treatment, significant changes were observed in the two groups regarding the VOCs content since some of them increased in the TBD group (namely, decanoic acid), whereas others (i.e., nonanal and ethanol) increased in the LFD one. Further, at baseline, short-chain fatty acids were positively related to inflammation and showed a significant decreasing trend after both diets compared to baseline values (namely, acetic and propanoic acid). Preliminary results from this pilot study suggest a potential positive intervention of TBD and LFD affecting the fecal metabolome composition in IBS-D patients.

How Metabolomics Provides Novel Insights on Celiac Disease and Gluten-Free Diet: A Narrative Review.

Celiac disease (CD) is an inflammatory autoimmune disorder triggered by the ingestion of gluten from wheat and other cereals. Nowadays, its positive diagnosis is based on invasive approaches such as the histological examination of intestinal biopsies and positive serology screening of antibodies. After proven diagnosis, the only admissible treatment for CD individuals is strict life-long adherence to gluten-free diet (GFD), although it is not a conclusive therapy. Acting by different mechanisms and with different etiologies, both CD and GFD have a great impact on gut microbiota that result in a different taxa composition. Altered production of specific metabolites reflects these microbiota changes. In this light, the currently available literature reports some suggestions about the possible use of specific metabolites, detected by meta-omics analyses, as potential biomarkers for a CD non-invasive diagnosis. To highlight insights about metabolomics application in CD study, we conducted a narrative dissertation of selected original articles published in the last decade. By applying a systematic search, it clearly emerged how the metabolomic signature appears to be contradictory, as well as poorly investigated.

Nutrients Bioaccessibility and Anti-inflammatory Features of Fermented Bee Pollen: A Comprehensive Investigation.

We compared raw bee-collected pollen (Raw-BCP), spontaneously fermented BCP (Unstarted-BCP), and BCP fermented with selected microbial starters (Started-BCP) to deepen whether fermentation may favorably affect the nutrients bioaccessibility and functional features of BCP. Under in vitro gastrointestinal batches, the highest serum-availability of phenolic compounds was found in Started-BCP, highlighting the positive effect exerted by selected microbial starters. The same effect was not found in spontaneously fermented BCP. In colon adenocarcinoma cell line-2 (Caco-2) cells stressed by a pro-inflammatory stimulus, the treatment with Started-BCP halted the increase of pro-inflammatory mediator's level. Started-BCP counteracted efficiently the deleterious effects of inflammatory stimuli on the integrity of the Caco-2 cells monolayer and its barrier function. Started-BCP successfully counteracted the H2O2-induced intracellular accumulation of reactive oxygen species (ROS) in Caco-2 cells. A protective role against lipopolysaccharide (LPS)-induced inflammation was exerted by Started-BCP in human keratinocytes. The same protective effects on Caco-2 and keratinocyte cell lines were negligible after treatments with Raw-BCP or Unstarted-BCP.

Metaproteomics Approach and Pathway Modulation in Obesity and Diabetes: A Narrative Review.

Low-grade inflammatory diseases revealed metabolic perturbations that have been linked to various phenotypes, including gut microbiota dysbiosis. In the last decade, metaproteomics has been used to investigate protein composition profiles at specific steps and in specific healthy/pathologic conditions. We applied a rigorous protocol that relied on PRISMA guidelines and filtering criteria to obtain an exhaustive study selection that finally resulted in a group of 10 studies, based on metaproteomics and that aim at investigating obesity and diabetes. This batch of studies was used to discuss specific microbial and human metaproteome alterations and metabolic patterns in subjects affected by diabetes (T1D and T2D) and obesity. We provided the main up- and down-regulated protein patterns in the inspected pathologies. Despite the available results, the evident paucity of metaproteomic data is to be considered as a limiting factor in drawing objective considerations. To date, ad hoc prepared metaproteomic databases collecting pathologic data and related metadata, together with standardized analysis protocols, are required to increase our knowledge on these widespread pathologies.