Search Results (39)

This research aimed to analyze the proteomic profile of the low-molecular mass fraction of salivary pools from patients with glioblastoma IDH wild type (GBM) to disclose the small protein and peptide components, including protein fragments, cryptides, and tumor-associated peptides, still lacking specific information in the literature, to the best of our knowledge. This fraction, corresponding to the unretained proteome fraction, was obtained by pretreating the acid-soluble fraction of saliva through Filter-Aided Sample Preparation devices with a filter molecular cutoff of 10 kDa. The fraction was analyzed by LC-MS in its entire form, without trypsin pre-digestion, following a top–down approach. Data from the analysis of pre- and post-operative salivary pools from patients with newly diagnosed and recurrent GBM were compared and discussed with data obtained in our previous study on the complementary salivary proteome fraction > 10 kDa analyzed by a bottom–up approach and data from the literature. The results highlighted a panel of GBM-associated peptide fragments from different protein precursors, namely, ANXA1, CFL1, GLUL, PFN1, H2AC12, ACTB, and HBB, which are suggested for further exploration as potential diagnostic and prognostic biomarkers and clinical applications. These findings, although providing only preliminary results on a small scale, offer new insights into the molecular characteristics of GBM tumor and lay the groundwork for further investigations on a large scale using saliva liquid biopsy for biomarker discovery and validation. The aim is to advance precision medicine and improve clinical outcomes in GBM, one of the most aggressive brain tumors with a poor prognosis, for which early diagnosis and monitoring of treatment response remain significant challenges. Full article

This study addressed the challenges posed by wet-grade maize distiller’s dried grains with solubles (DDGS), which are characterized by high moisture and complex fibers that limit their storage and utilization in poultry feed. Three experiments were conducted to enhance their nutritional value through enzymatic and solid-state fermentation treatments. In vitro pre-digestion using multiple enzymes significantly improved dry matter solubility (DMS) and reducing sugar yield for maize DDGS and the ingredient maize germ meal (MGM). Using optimized parameters, wet-based DDGS-MGM was subjected to solid-state fermentation with 500 mg/kg of cellulase and 200 mg/kg of the X1 enzyme (a laboratory-developed multi-enzyme complex), and this treatment enhanced both DMS and reducing sugar yield, and the resulting fermented product was subsequently applied in further experiments. In the broiler trial, forty 22-day-old Arbor Acres broilers with similar body weights were randomly assigned to five treatment groups, including the control group, (50% DDGS + 50% MGM) unfermented group, (62.5% DDGS + 37.5% MGM) unfermented group, (50% DDGS + 50% MGM) fermented group, and (62.5% DDGS + 37.5% MGM) fermented group, with eight replicates per treatment (one broiler per replicate). Replacement of 30% of the basal diet with fermented 50:50 DDGS-MGM material significantly increased apparent metabolizable energy (AME) and nitrogen-corrected AME by 2.74 MJ/kg and 2.73 MJ/kg, respectively, corresponding to improvements of 39.60% and 40.81% compared to the unfermented control (p < 0.05). Economic analysis indicated that using 5% fermented DDGS-MGM in feed reduced cost by 20.45 RMB per metric ton. These findings demonstrate that bioprocessing can improve the utilization and economic value of maize processing by-products, although further validation under practical conditions is needed. Full article

The gut microbiome of women can change after menopause, and during this phase women can also be more susceptible to vaginal dysbiosis. Recent studies have explored the probiotic potential of Lactobacillus crispatus BC4 and Lactobacillus gasseri BC9 against various pathogens and their use as co-starters in foods. However, their effects on the gut microbiota of post-menopausal women, who are more prone to dysbiosis, have not been examined. This study investigated the effects of predigested soy beverages (INFOGEST) containing BC4 and BC9 (encapsulated or not) on the composition and metabolic activity of the gut microbiota in post-menopausal women, using a fecal batch culture model. Parameters such as pH, gas, SCFAs, and microbiota composition (targeted qPCR and 16S rRNA gene sequencing) were assessed. The study, while highlighting a strong variability among donors, showed differences in gut microbiota response to the tested products. For instance, donor 2 showed a significant increase in bifidobacteria with BC4 + BC9 and E-BC9, while BC4 increased Ruminococcaceae in donors 1 and 3, and E-BC4 and E-BC9 enhanced Akkermansia in donor 1. BC4, E-BC4, E-BC9, and E-BC4 + BC9 significantly impacted metabolic activity, as measured by SCFAs, compared to other samples. However, no significant differences in gas production were observed. Full article

Background/Objectives: After birth, mothers provide the best nutrition for the healthy growth and development of their infants and the developing gut microbiota through breastfeeding. When breastfeeding is not or insufficiently available, infant formula is the only safe alternative. The production of infant formula includes heat-processing, which may induce protein glycation. Protein glycation has been shown to reduce protein digestion and absorption. The reduction in protein digestion and absorption because of protein glycation has been speculated to also impact gut comfort parameters as well as overnight sleep. Methods: As this could be partially due to the effect on the bacteria that reside in the infant’s gastrointestinal tract, we investigated whether protein glycation in infant formula impacts the composition and activity of infant gut microbiota by performing an in vitro study using the CoMiniGut colon model and fecal inocula obtained from a healthy six-month-old term infant. Incubations were performed for 24 h using a predigested infant formula-supplemented medium with varying levels of glycation (6.5–44.5%). Results: Our data indicate that high protein glycation increases microbial diversity and the relative abundance of Clostridium neonatale from 6.4% of the inoculum to around 25.5% of 20.8% glycation. Interestingly, propionate levels were inversely correlated with protein glycation levels after 24 h of incubation, with the 44.5% blocked lysine sample giving rise to 60% lower propionate levels as compared to the 6.4% sample. Higher propionate levels have been linked with longer uninterrupted sleep overnight, which could be indicative of the underlying mechanism of reduced crying/fussy time during nights for infants fed with a formula containing lower amounts of glycated protein. Full article

Milk boasts an array of potent bioactive compounds, such as lactoferrin (Lf), immunoglobulins, and functional proteins, all delivering substantial therapeutic benefits. In this study, Immune Powder (a functional dairy formulation) and its primary component called Fractionated Milk Protein (FMP) containing Lf, zinc, and immunoglobulins and formulated by Ausnutria Pty Ltd. were evaluated for their potential broad-spectrum pharmacological activity. In particular, this study investigated the antibacterial (against pathogenic Escherichia coli), prebiotic (promoting Lactobacillus delbrueckii growth), anti-inflammatory (inhibition of NO production in RAW264.7 macrophages), and antiviral (against human coronavirus 229E) effects of the samples. In addition, the impact of simulated gastric digestion on the efficacy of the samples was explored. LCMS-based proteomics was implemented to unveil cellular and molecular mechanisms underlying antiviral activity. The Immune Powder demonstrated antibacterial activity against E. coli (up to 99.74 ± 11.47% inhibition), coupled with prebiotic action (10.84 ± 2.2 viability fold-change), albeit these activities diminished post-digestion (p < 0.01). The Immune Powder effectively mitigated NO production in lipopolysaccharide-stimulated RAW264.7 macrophages, with declining efficacy post-digestion (p < 0.0001). The Immune Powder showed similar antiviral activity before and after digestion (p > 0.05) with up to 3-fold improvement. Likewise, FMP exhibited antibacterial potency pre-digestion at high concentrations (95.56 ± 1.23% inhibition at 125 mg/mL) and post-digestion at lower doses (61.82 ± 5.58% inhibition at 3906.25 µg/mL). FMP also showed enhanced prebiotic activity post-digestion (p < 0.0001), NO inhibition pre-digestion, and significant antiviral activity. The proteomics study suggested that the formulation and its primary component shared similar antiviral mechanisms by inhibiting scavenger receptor binding and extracellular matrix interaction. Full article

The absorption of dietary phosphorus typically begins with the digestive phase, where various chemical processes take place. These include the solubilization of calcium phosphates by gastric acid in the stomach, as well as the enzymatic breakdown of various organic phosphorus compounds within the intestinal lumen. Enhancing the digestive phase can be achieved by pre-digesting diets or designing them to be readily digestible, which can be especially advantageous for fish with limited digestive capabilities. This improvement may involve supplementing the diets with phytase and organic acids, fermenting feed ingredients, and selecting highly digestible ingredients. Following the digestive phase, solubilized inorganic phosphates and small organic phosphates are absorbed across the intestinal epithelium. This absorptive process is governed by numerous bodily mechanisms that are not easily altered or enhanced. Nonetheless, comprehending these absorptive mechanisms of dietary phosphorus may pave the way for the development of novel methods to increase dietary phosphorus absorption. Full article

A predigested product from arachidonic acid oil (ARA) and docosahexaenoic acid (DHA) oil in a 2:1 (w/w) ratio has been developed and evaluated in an in vitro digestion model. To produce this predigested lipid mixture, first, the two oils were enzymatically hydrolyzed up to 90% of free fatty acids (FFAs) were achieved. Then, these two fatty acid (FA) mixtures were mixed in a 2:1 ARA-to-DHA ratio (w/w) and enzymatically esterified with glycerol to produce a mixture of FFAs, mono-, di-, and triacylglycerides. Different glycerol ratios and temperatures were evaluated. The best results were attained at 10 °C and a glycerol-to-FA molar ratio of 3:1. The bio-accessibility of this predigested mixture was studied in an in vitro digestion model. A total of 90% of the digestion product was found in the micellar phase, which contained 30% monoacylglycerides, more than 50% FFAs, and a very small amount of triacylglycerols (3% w/w). All these data indicate an excellent bio-accessibility of this predigested mixture. Full article

Western diets are rich in gluten-containing products, which are frequently poorly digested. The human large intestine harbors microorganisms able to metabolize undigested gluten fragments that have escaped digestion by human enzymatic activities. The aim of this work was obtaining and culturing complex human gut microbial communities derived from gluten metabolism to model the dynamics of healthy human large intestine microbiota associated with different gluten forms. For this purpose, stool samples from six healthy volunteers were inoculated in media containing predigested gluten or predigested gluten plus non-digested gluten. Passages were carried out every 24 h for 15 days in the same medium and community composition along time was studied via V3–V4 16S rDNA sequencing. Diverse microbial communities were successfully obtained. Moreover, communities were shown to be maintained in culture with stable composition for 14 days. Under non-digested gluten presence, communities were enriched in members of Bacillota, such as Lachnospiraceae, Clostridiaceae, Streptococcaceae, Peptoniphilaceae, Selenomonadaceae or Erysipelotrichaceae, and members of Actinomycetota, such as Bifidobacteriaceae and Eggerthellaceae. Contrarily, communities exposed to digested gluten were enriched in Pseudomonadota. Hence, this study shows a method for culture and stable maintenance of gut communities derived from gluten metabolism. This method enables the analysis of microbial metabolism of gluten in the gut from a community perspective. Full article

Inflammatory bowel disease (IBD) is characterized by chronic intestinal inflammation and its treatment varies widely; however, when inflammation is high, a complete nutrient containing pre-digested elemental diet (ED) is used to preserve the intestinal tract. In this study, we investigated the mechanisms underlying the effectiveness of EDs for IBD using mice. C57BL/6 mice were orally treated with the ED (5 mL/day) and its ingredient L-tryptophan (Trp) (1–100 mg/kg), respectively. Flow cytometry analysis revealed that treatment with the ED and Trp (10 and 100 mg/kg) significantly increased the percentage of splenic CD4+-/CD25+-/Foxp3+ regulatory T cells (Tregs). In the 2% DSS-induced colitis-mouse model, Trp administration (100 mg/kg) led to a significant decrease in TNF-α and increase in IL-10 in the serum as well as a significant decrease in the inflammation score. Furthermore, the aryl hydrocarbon receptor (AhR) agonistic activity, which is a key function of Treg induction, of Trp and 15 Trp metabolites was characterized using a highly sensitive DR-EcoScreen cell assay. Five Trp metabolites, including L-kynurenine, acted as AhR agonists, while Trp did not. Taken together, these results suggest that the ED treatment has a Trp-dependent immunoregulatory effect, and several Trp metabolites that activate the AhR might contribute to induction of remission in patients with IBD. Full article

Auricularia auricula-judae (AAJ) has been cultivated for food in China for centuries, and is also used as a folk medicine for the regulation of glucose and lipid metabolism. However, there are few studies on the effects of different processing technologies on the therapeutic efficacy of AAJ to date. This study investigated the effectiveness of the AAJ made by using superfine grinding and enzymatic pre-digestion technologies, respectively, in a high-fat diet obese rat model. It was found that oral administrations of two AAJ products significantly alleviated dyslipidemia by decreasing serum lipid levels and restoring liver functions. AAJ products made by using pre-digestion technology have appreciable potential to ameliorate lipid metabolic disorders over other products, possibly due to the higher levels of dietary fiber, crude polysaccharides, and total flavonoids released from AAJ during processing. By analysis of transcriptome sequencing and protein expression, it was clear that starch and sucrose metabolism and glycerolipid metabolism-related factors involved in fatty acid synthesis and metabolism in the liver of obese rats were significantly improved. This study gives further evidence that AAJ significantly ameliorates the progression of glucose and lipid metabolism in obese rats. Moreover, this study demonstrated for the first time that the pre-digestion method may be a better and more efficient processing approach for the improvement of AAJ bioavailability. Full article

Background: The microbial metabolites short-chain fatty acids (SCFAs) are proposed to largely contribute to improvements in metabolic health associated with dietary fiber (saccharolytic) fermentation. Nevertheless, towards the distal colon, fermentable carbohydrates become depleted, and gut bacteria switches towards protein (proteolytic) fermentation. This yields a diversity of metabolites like branched-chain fatty acids (BCFAs), often considered detrimental to metabolic health. We previously demonstrated that acute SCFA administration to the distal, but not the proximal colon, led to beneficial alterations in human substrate and energy metabolism. Hence, we hypothesize that a switch from proteolytic to saccharolytic fermentation in the distal colon has the most pronounced metabolic health effects and aimed to identify a complex carbohydrate mixture capable of inducing such a microbial substrate switch. Methods: The TIM-2 model, an in vitro computer-controlled dynamic model, was used to mimic colonic fermentation, simulating amongst others body temperature, luminal pH, microbial metabolite absorption, and peristalsis. TIM-2 was inoculated with standardized pooled microbiota from individuals with overweight/obesity and disturbed glucose homeostasis. After an overnight adaptation period, pre-digested proteins were added to the model to create a high protein background. Subsequently, either separately or in combination, potato fiber, native inulin from chicory, pectin from sugar beet, or no fibers (protein control) were administered. Samples of the lumen and dialysate were taken at various time points and assessed for proximal (0–8 h) and distal (8–24 h) SCFA and BCFA levels. Results: Of all the tested combinations, combining potato fiber and pectin resulted in the highest distal SCFA production (26.3 vs 6.4 mmol) and SCFA:BCFA ratio (13.3 vs 2.2) compared to the protein control. Discussion: The combination of potato fiber and pectin was best able to increase distal SCFA production in pooled microbiota of individuals who were overweight/obese. To assess whether these results translate to improvements in metabolic health, we are currently conducting a 12-week double-blind placebo-controlled randomized study. 44 individuals who are overweight/obese and have a disturbed glucose homeostasis are randomized to supplementation with a potato fiber/pectin mixture or placebo (maltodextrin) while consuming an eucaloric high protein diet (25 E% protein). The primary outcome will be the change in peripheral insulin sensitivity. Full article

Infant microbiota shaping strictly influences newborns’ well-being and long-term health, and babies born by cesarean-section and formula-fed generally show low microbial gut diversity and are more prone to develop various disorders. The supplementation with beneficial microbes of vaginal origin or derivatives (postbiotics, including heat-inactivated cells) represents a valid strategy to drive the correct gut microbiota shaping. Here, we explored for the first time the bifidogenic activity of a heat-killed vaginal strain (Limosilactobacillus vaginalis BC17), in addition to the assessment of its safety. L. vaginalis BC17 whole genome was sequenced by Nanopore technology and highlighted the absence of antibiotic resistance genes and virulence factors, indicating the strain safety profile for human health. MIC values confirmed that L. vaginalis BC17 is susceptible to widely employed antibiotics. Heat-killed BC17 cells significantly enhanced the planktonic growth of Bifidobacterium spp. For the first time, stimulating effects were observed also toward biofilm formation of bifidobacteria and their pre-formed biofilms. Conversely, heat-killed BC17 cells exerted antibacterial and anti-biofilms activities against Gram-positive and Gram-negative pathogens. Lyophilized heat-killed BC17 cells were formulated in a sunflower oil suspension (10¹⁰ heat-killed cell/g) intended for infant oral intake. This possessed optimal technological (i.e., re-dispersibility and stability) and functional properties (i.e., bifidogenic activity) that were maintained even after pre-digestion in acidic conditions. Full article

NUTRIOSE^® (Roquette, Lestrem, France) is a resistant dextrin with well-established prebiotic effects. This study evaluated the indirect effects of pre-digested NUTRIOSE^® on host immune response and gut barrier integrity. Fecal samples from eight healthy donors were inoculated in a Colon-on-a-plate^® system (ProDigest, Ghent, Belgium) with or without NUTRIOSE^® supplementation. Following 48 h fermentation, colonic suspensions were tested in a Caco-2/THP1-Blue™ co-culture system to determine their effects on gut barrier activity (transepithelial electrical resistance) and immune response following lipopolysaccharide stimulation. Additionally, changes in short-chain fatty acid levels (SCFA) and microbial community composition following a 48 h fermentation in the Colon-on-a-plate^® system were measured. Across all donors, immune-mediated intestinal barrier damage was significantly reduced with NUTRIOSE^®-supplemented colonic suspensions versus blank. Additionally, IL-6 and IL-10 levels were significantly increased, and the level of the neutrophil chemoattractant IL-8 was significantly decreased with NUTRIOSE^®-supplemented colonic suspensions versus blank in the co-culture models following lipopolysaccharide stimulation. These beneficial effects of NUTRIOSE^® supplementation were likely due to increased acetate and propionate levels and the enrichment of SCFA-producing bacteria. NUTRIOSE^® was well fermented by the colonic bacteria of all eight donors and had protective effects on inflammation-induced disruption of the intestinal epithelial barrier and strong anti-inflammatory effects. Full article

The presence of proteases and their resulting level of activity on human milk (HM) proteins may aid in the generation of indigenous peptides as part of a pre-digestion process, of which some have potential bioactivity for the infant. The present study investigated the relative abundance of indigenous peptides and their cleavage products in relation to the abundance of observed proteases and protease inhibitors. The proteomes and peptidomes in twelve HM samples, representing six donors at lactation months 1 and 3, were profiled. In the proteome, 39 proteases and 29 protease inhibitors were identified in 2/3 of the samples. Cathepsin D was found to be present in higher abundance in the proteome compared with plasmin, while peptides originating from plasmin cleavage were more abundant than peptides from cathepsin D cleavage. As both proteases are present as a system of pro- and active- forms, their activation indexes were calculated. Plasmin was more active in lactation month 3 than month 1, which correlated with the total relative abundance of the cleavage product ascribed to plasmin. By searching the identified indigenous peptides in the milk bioactive peptide database, 283 peptides were ascribed to 10 groups of bioactivities. Antimicrobial peptides were significantly more abundant in month 1 than month 3; this group comprised 103 peptides, originating from the β-CN C-terminal region. Full article

Proteases play a role in different processes for protozoans and for the free-living amoeba Acanthamoeba. Some of these processes are related to pathogenicity and to encystment. In this study we describe the discovery of a protease with antimicrobial activity produced by Acanthamoeba. To identify it, we developed a novel zymogram using bacteria as an in-gel substrate that can help identify proteins capable of bacterial degradation. We used chromatography to isolate the proteases and showed that it quickly degrades in the environment. Additionally, we identified overexpressed proteases during encystment. The study of proteases from Acanthamoeba can serve several purposes including new antimicrobial proteins that the amoeba can use for potentially predigesting prokaryotes. Secondly, it can help with the identification of potential new therapies against Acanthamoeba infection. Full article