In vitro faecal fermentation of Tritordeum breads and its effect on the human gut health.

Spontaneous fermentation of Tritordeum flour enhances the nutritional potential of this hybrid cereal. However, the effect of consumption of Tritordeum sourdough bread (SDB) on gut health remains to be elucidated. This study investigated the effect of in vitro digestion and faecal fermentation of SDB compared to that of traditional baker's yeast (BYB) Tritordeum bread. After 24-h anaerobic faecal fermentation, both SDB and BYB (1% w/v) induced an increase in the relative abundances of Bifidobacterium, Megasphaera, Mitsuokella, and Phascolarctobacterium genera compared to baseline, while concentrations of acetate and butyrate were significantly higher at 24 h for SDB compared to those for BYB. Integrity of intestinal epithelium, as assessed through in vitro trans-epithelial electrical resistance (TEER) assay, was slightly increased after incubation with SDB fermentation supernatants, but not after incubation with BYB fermentation supernatants. The SDB stimulated in vitro mucosal immune response by inducing early secretion of inflammatory cytokines, IL-6 and TNF-α, followed by downregulation of the inflammatory trigger through induction of anti-inflammatory IL-10 expression. Overall, our findings suggest that Tritordeum sourdough can modulate gut microbiota fermentation activity and positively impact the gut health.

Salivary microbial profiles associate with responsiveness to warning oral sensations and dietary intakes.

Oral microbiota-host interactions are gaining recognition as potential factors contributing to interindividual variations in taste perception. However, whether such possible links imply specific bacterial co-occurrence networks remains unknown. To address this issue, we used 16 s rRNA gene sequencing to profile the salivary microbiota of 100 healthy individuals (52 % women; 18-30 y/o), who provided hedonic and psychophysical responses to 5 liquid and 5 solid commercially-available foods, each chosen to elicit a target sensation (sweet, sour, bitter, salty, pungent). The same cohort also completed several psychometric measures and a 4-day food diary. Unsupervised data-driven clustering of genus-level Aitchison distances supported the existence of two salivary microbial profiles (CL-1, CL-2). While CL-1 (n = 57; 49.1 % women) exhibited higher α-diversity metrics and was enriched in microbial genera assigned to the class Clostridia (e.g., Lachnospiraceae_[G-3]), CL-2 (n = 43; 55.8 % women) harbored greater amounts of taxa with potential cariogenic effects (e.g., genus Lactobacillus) and significantly lower abundances of inferred MetaCyc pathways related to the metabolic fate of acetate. Intriguingly, CL-2 showed enhanced responsiveness to warning oral sensations (bitter, sour, astringent) and a higher propensity to crave sweet foods or engage in prosocial behaviors. Further, the same cluster reported habitually consuming more simple carbohydrates and fewer beneficial nutrients (vegetable proteins, monounsaturated fatty acids). In summary, while the mediating role of participants' baseline diet on findings can not be definitively excluded, this work provides evidence suggesting that microbe-microbe and microbe-taste interactions may exert an influence on dietary habits and motivates further research to uncover a potential "core" taste-related salivary microbiota.

Microbial and metabolic characterization of organic artisanal sauerkraut fermentation and study of gut health-promoting properties of sauerkraut brine.

Sauerkraut is a traditionally fermented cabbage, and recent evidence suggests that it has beneficial properties for human health. In this work, a multi-disciplinary approach was employed to characterize the fermentation process and gut health-promoting properties of locally produced, organic sauerkraut from two distinct producers, SK1 and SK2. 16S rRNA metataxonomics showed that bacterial diversity gradually decreased as fermentation progressed. Differences in sauerkraut microbiota composition were observed between the two producers, especially at the start of fermentation. Lactic acid bacteria (LAB) dominated the microbiota after 35 days, with Lactiplantibacillus being the dominant genus in both sauerkraut products, together with Leuconostoc and Paucilactobacillus in SK1, and with Pediococcus, Levilactibacillus, and Leuconostoc in SK2. LAB reached between 7 and 8 Log CFU/mL brine at the end of fermentation (35 days), while pH lowering happened within the first week of fermentation. A total of 220 LAB strains, corresponding to 133 RAPD-PCR biotypes, were successfully isolated. Lactiplantibacillus plantarum and Lactiplantibacillus pentosus accounted for 67% of all SK1 isolates, and Lactiplantibacillus plantarum/paraplantarum and Leuconostoc mesenteroides represented 72% of all the isolates from SK2. 1H-NMR analysis revealed significant changes in microbial metabolite profiles during the fermentation process, with lactic and acetic acids, as well as amino acids, amines, and uracil, being the dominant metabolites quantified. Sauerkraut brine did not affect trans-epithelial electrical resistance through a Caco-2 cell monolayer as a measure of gut barrier function. However, significant modulation of inflammatory response after LPS stimulation was observed in PBMCs-Caco-2 co-culture. Sauerkraut brine supported a robust inflammatory response to endotoxin, by increasing TNF-α and IL-6 production while also stimulating the anti-inflammatory IL-10, therefore suggesting positive resolution of inflammation after 24 h and supporting the potential of sauerkraut brine to regulate intestinal immune function.

Processed Animal Proteins from Insect and Poultry By-Products in a Fish Meal-Free Diet for Rainbow Trout: Impact on Intestinal Microbiota and Inflammatory Markers.

Sustainability of aquaculture is tied to the origin of feed ingredients. In search of sustainable fish meal-free formulations for rainbow trout, we evaluated the effect of Hermetia illucens meal (H) and poultry by-product meal (P), singly (10, 30, and 60% of either H or P) or in combination (10% H + 50% P, H10P50), as partial replacement of vegetable protein (VM) on gut microbiota (GM), inflammatory, and immune biomarkers. Fish fed the mixture H10P50 had the best growth performance. H, P, and especially the combination H10P50 partially restored α-diversity that was negatively affected by VM. Diets did not differ in the Firmicutes:Proteobacteria ratio, although the relative abundance of Gammaproteobacteria was reduced in H and was higher in P and in the fishmeal control. H had higher relative abundance of chitin-degrading Actinomyces and Bacillus, Dorea, and Enterococcus. Actinomyces was also higher in H feed, suggesting feed-chain microbiome transmission. P increased the relative abundance of protein degraders Paeniclostridium and Bacteroidales. IL-1ß, IL-10, TGF-ß, COX-2, and TCR-ß gene expression in the midgut and head kidney and plasma lipopolysaccharide (LPS) revealed that the diets did not compromise the gut barrier function or induce inflammation. H, P, and H10P50 therefore appear valid protein sources in fishmeal-free aquafeeds.

Effects of Exogenous Dietary Advanced Glycation End Products on the Cross-Talk Mechanisms Linking Microbiota to Metabolic Inflammation.

Heat-processed diets contain high amounts of advanced glycation end products (AGEs). Here we explore the impact of an AGE-enriched diet on markers of metabolic and inflammatory disorders as well as on gut microbiota composition and plasma proteins glycosylation pattern. C57BL/6 mice were allocated into control diet (CD, n = 15) and AGE-enriched diet (AGE-D, n = 15) for 22 weeks. AGE-D was prepared replacing casein by methylglyoxal hydroimidazolone-modified casein. AGE-D evoked increased insulin and a significant reduction of GIP/GLP-1 incretins and ghrelin plasma levels, altered glucose tolerance, and impaired insulin signaling transduction in the skeletal muscle. Moreover, AGE-D modified the systemic glycosylation profile, as analyzed by lectin microarray, and increased Nε-carboxymethyllysine immunoreactivity and AGEs receptor levels in ileum and submandibular glands. These effects were associated to increased systemic levels of cytokines and impaired gut microbial composition and homeostasis. Significant correlations were recorded between changes in bacterial population and in incretins and inflammatory markers levels. Overall, our data indicates that chronic exposure to dietary AGEs lead to a significant unbalance in incretins axis, markers of metabolic inflammation, and a reshape of both the intestinal microbiota and plasma protein glycosylation profile, suggesting intriguing pathological mechanisms underlying AGEs-induced metabolic derangements.

Baricitinib counteracts metaflammation, thus protecting against diet-induced metabolic abnormalities in mice.

OBJECTIVE: Recent evidence suggests the substantial pathogenic role of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway in the development of low-grade chronic inflammatory response, known as "metaflammation," which contributes to obesity and type 2 diabetes. In this study, we investigated the effects of the JAK1/2 inhibitor baricitinib, recently approved for the treatment of rheumatoid arthritis, in a murine high-fat-high sugar diet model. METHODS: Male C57BL/6 mice were fed with a control normal diet (ND) or a high-fat-high sugar diet (HD) for 22 weeks. A sub-group of HD fed mice was treated with baricitinib (10 mg/kg die, p.o.) for the last 16 weeks (HD + Bar). RESULTS: HD feeding resulted in obesity, insulin-resistance, hypercholesterolemia and alterations in gut microbial composition. The metabolic abnormalities were dramatically reduced by chronic baricitinib administration. Treatment of HD mice with baricitinib did not change the diet-induced alterations in the gut, but restored insulin signaling in the liver and skeletal muscle, resulting in improvements of diet-induced myosteatosis, mesangial expansion and associated proteinuria. The skeletal muscle and renal protection were due to inhibition of the local JAK2-STAT2 pathway by baricitinib. We also demonstrated that restored tissue levels of JAK2-STAT2 activity were associated with a significant reduction in cytokine levels in the blood. CONCLUSIONS: In summary, our data suggest that the JAK2-STAT2 pathway may represent a novel candidate for the treatment of diet-related metabolic derangements, with the potential for EMA- and FDA-approved JAK inhibitors to be repurposed for the treatment of type 2 diabetes and/or its complications.

Ultrasound and interstitial lung disease: use and limitations.

The Connective Tissue Diseases (CTDs)-related Interstitial Lung Disease (ILD) early diagnosis by Transthoracic Ultrasound (TUS) still arises several issues. Gutierrez et al. clearly underlined the current role of ultrasound artifacts for ILD definition according to some Authors. In this Letter to the Editor, we would like to highlight the proper role of TUS and its pitfalls.