Lactobacillus casei-fermented blueberry pomace ameliorates colonic barrier function in high fat diet mice through MAPK-NF-κB-MLCK signaling pathway

Enteromorpha prolifera polysaccharide-Fe (III) complex promotes intestinal development as a new iron supplement

Iron is a crucial micronutrient, and its deficiency can have detrimental effects on the health of infants. Dietary polysaccharide-iron (III) complexes (PICs) are promising for addressing iron deficiency due to their minimal adverse reactions and high iron absorption rate. This study aimed to investigate the effects of dietary Enteromorpha prolifera polysaccharide-Fe (III) complex (EP-Fe) on newborns, using 3-day weaned piglets as the iron-deficiency model. Results showed that EP-Fe improved iron levels and promoted intestinal development in piglets. Transcriptome sequencing revealed that EP-Fe increased the survival of intestinal epithelial cells under hypoxia by upregulating the expression of genes that promote the development of the vascular system. Additionally, EP-Fe enhanced the mucosal barrier functions by inhibiting myosin light chain kinase (MLCK)/phosphorylated myosin light chain (p-MLC) signaling pathway to increase the expression of intestinal tight junction proteins. Furthermore, the 16S rRNA gene sequencing of gut microbiota showed that EP-Fe promoted the enrichment of Bacteroides_fragilis and other gut microbes that can metabolize carbohydrates. In conclusion, EP-Fe is an effective iron supplement for newborns, and it can be developed as a comprehensive nutritional supplement.

Chlorogenic Acid/Linoleic Acid-Fortified Wheat-Resistant Starch Ameliorates High-Fat Diet-Induced Gut Barrier Damage by Modulating Gut Metabolism

This study aimed to investigate alterations in gut microbiota and metabolites mediated by wheat-resistant starch and its repair of gut barrier dysfunction induced by a high-fat diet (HFD). Structural data revealed that chlorogenic acid (CA)/linoleic acid (LA) functioned through noncovalent interactions to form a more ordered structure and fortify antidigestibility in wheat starch (WS)-CA/LA complexes; the resistant starch (RS) contents of WS-CA, WS-LA, and WS-CA-LA complexes were 23.40 ± 1.56%, 21.25 ± 1.87%, and 35.47 ± 2.16%, respectively. Dietary intervention with WS-CA/LA complexes effectively suppressed detrimental alterations in colon tissue morphology induced by HFD and repaired the gut barrier in ZO-1 and MUC-2 levels. WS-CA/LA complexes could augment gut barrier-promoting microbes including Parabacteroides, Bacteroides, and Muribaculum, accompanied by an increase in short-chain fatty acids (SCFAs) and elevated expression of SCFA receptors. Moreover, WS-CA/LA complexes modulated secondary bile acid metabolism by decreasing taurochenodeoxycholic, cholic, and deoxycholic acids, leading to the activation of bile acid receptors. Collectively, this study offered guiding significance in the manufacture of functional diets for a weak gut barrier.

Covalent conjugation with polyphenol reduced the sensitization of walnut and ameliorated allergy by enhancing intestinal epithelial barrier in mice

In order to reduce the sensitization of walnut protein (WP), the effects of the interaction between WP and (-)-Epigallocatechin gallate (EGCG), quercetin, trans-ferulic acid, and resveratrol were investigated. Covalent and non-covalent conjugations were compared. The results suggested that covalent conjugation reduced the free amino acid content, sulfhydryl content, and surface hydrophobicity. When compared to non-covalent conjugation, covalent modification showed a lower IgE binding capacity, accompanied by changes in protein conformation. Moreover, animal experiments revealed that there were up-regulation of transforming growth factor-β, T-box expressed in t cells, and forkhead transcription factor Foxp3 mRNA expression, and down-regulation of IL-4, IL-17, GATA binding protein 3 and retinoid-related orphan nuclear receptor γt mRNA expression in the conjugate groups. These results suggested that covalent conjugation of polyphenols, especially EGCG, likely ameliorated allergy by promoting Th1/Th2 and Treg/Th17 balance and alleviating allergy-induced intestinal barrier damage, which might be a support in reducing the allergenicity of WP.

Lactobacillus Casei-fermented Amomum Xanthioides Mitigates non-alcoholic fatty liver disease in a high-fat diet mice model

Non-alcoholic fatty liver disease (NAFLD) is a substantial global health issue owing to its high prevalence and the lack of effective therapies. Fermentation of medicinal herbs has always been considered a feasible strategy for enhancing efficacy in treating various ailments. This study aimed to investigate the potential benefits of the Lactobacillus casei-fermented Amomum xanthioides (LAX) on NAFLD in a high-fat diet model. HFD-fed C57BL6/j mice were administered with 200 mg/kg of LAX or unfermented Amomum xanthioides (AX) or 100 mg/kg of metformin for 6 weeks from the 4th week. The 10-week HFD-induced alterations of hepatic lipid accumulation and hepatic inflammation were significantly attenuated by LAX dominantly (more than AX or metformin), which evidenced by pathohistological findings, lipid contents, inflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)- 6 and IL-1β, oxidative parameters such as reactive oxygen species (ROS) and malondialdehyde (MDA), and molecular changes reversely between lipogenic proteins such as glycerol-3-phosphate acyltransferase (GPAM) and sterol regulatory element-binding protein (SREBP)- 1, and lipolytic proteins including peroxisome proliferator-activated receptor (PPAR-α) and AMP-activated kinase (AMPK)-α in the liver tissues. In addition, the abnormal serum lipid parameters (triglyceride, total cholesterol and LDL-cholesterol) notably ameliorated by LAX. In conclusion, these findings support the potential of LAX as a promising plant-derived remedy for NAFLD.

Raspberry polyphenols alleviate neurodegenerative diseases: through gut microbiota and ROS signals

Neurodegenerative diseases are neurological disorders that become more prevalent with age, usually caused by damage or loss of neurons or their myelin sheaths, such as Alzheimer's disease and epilepsy. Reactive oxygen species (ROS) are important triggers for neurodegenerative disease development, and mitigation of oxidative stress caused by ROS imbalance in the human body is important for the treatment of these diseases. As a widespread delicious fruit, the raspberry is widely used in the field of food and medicine because of its abundant polyphenols and other bioactive substances. Polyphenols from a wide variety of raspberry sources could alleviate neurodegenerative diseases. This review aims to summarize the current roles of these polyphenols in maintaining neurological stability by regulating the composition and metabolism of the intestinal flora and the gut-brain axis signal transmission. Especially, we discuss the therapeutic effects on neurodegenerative diseases of raspberry polyphenols through intestinal microorganisms and ROS signals, by means of summary and analysis. Finally, methods of improving the digestibility and utilization of raspberry polyphenols are proposed, which will provide a potential way for raspberry polyphenols to guarantee the health of the human nervous system.

Wild blueberry (V. angustifolium) improves TNFα-induced cell barrier permeability through claudin-1 and oxidative stress modulation in Caco-2 cells

Increasing evidence links the impairment of intestinal permeability (IP), a feature of the intestinal barrier, to numerous dysmetabolic and dysfunctional conditions. Several host and environmental factors, including dietary factors, can negatively and/or positively affect IP. In this regard, polyphenol-rich foods including berries have been proposed as potential IP modulators. However, the exact mechanisms involved are not yet fully elucidated. The aim of the present study was to evaluate the effect of a wild blueberry (WB; V. angustifolium) powder, naturally rich in polyphenols, to affect Caco-2 cell monolayer permeability and to identify the potential mechanisms in modulating the IP process. Caco-2 cells were incubated with TNF-α (10 ng mL-1), as a pro-inflammatory stimulus, and supplemented for 24 hours with different concentrations (1 and 5 mg mL-1) of WB powder. The integrity of the intestinal cell monolayer was evaluated by measuring the transepithelial electrical resistance (TEER) and the paracellular transport of FITC-dextran. In addition, the production of the tight junction proteins, such as claudin-1 and occludin, as well as protein carbonyl and 8-hydroxy 2 deoxyguanosine, as oxidative stress markers, were quantified in the supernatant by ELISA kits. Overall, the treatment with WB powder (5 mg mL-1) mitigated the loss of Caco-2 cell barrier integrity, as documented by an increase in TEER and a reduction in FITC values. This modulation was accompanied by an upregulation of claudin-1 and a reduction of 8-OHdG. Conversely, no effect was documented for the lower concentration (1 mg mL-1) and the other IP markers, as well as oxidative stress markers analysed. In conclusion, our findings suggest a potential role of WB in the modulation of cell barrier integrity. This modulation process could be attributed to an increase in claudin-1 expression and a reduction in 8-OHdG. Further studies should be performed to corroborate the results obtained. In addition, since the effects were observed at doses of WB achievable with the diet, these findings should be substantiated also through in vivo approaches.