Ameliorating role of Tetrastigma hemsleyanum polysaccharides in antibiotic-induced intestinal mucosal barrier dysfunction in mice based on microbiome and metabolome analyses

Revealing quality chemicals of Tetrastigma hemsleyanum roots in different geographical origins using untargeted metabolomics and random-forest based spectrum-effect analysis

Tetrastigma hemsleyanum root is a popular functional food in China, and the price varies based on the origin of the product. The link between the origin, metabolic profile, and bioactivity of T. hemsleyanum must be investigated. This study compares the metabolic profiles of 254 samples collected from eight different areas with 49 potential key chemical markers using plant metabolomics. The metabolic pathways of the five critical flavonoid metabolites were annotated and enriched using the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. Moreover, a random forest model aiding the spectrum-effect relationship analysis was developed for the first time indicating catechin and darendoside B as potential quality markers of antioxidant activity. The findings of this study provide a comprehensive understanding of the chemical composition and bioactive compounds of T. hemsleyanum as well as valuable information on the evaluation of the quality of various samples and products in the market.

Fermented Gracilaria lemaneiformis polysaccharides alleviate food allergy by regulating Treg cells and gut microbiota

Food allergy has a significant impact on the health and well-being of individuals, affecting both their physical and mental states. Research on natural bioactive compounds, such as polysaccharides extracted from seaweeds, holds great promise in the treatment of food allergies. In this study, fermented Gracilaria lemaneiformis polysaccharides (F-GLSP) were prepared using probiotic fermentation. Probiotic fermentation of Gracilaria lemaneiformis reduces the particle size of polysaccharides. To compare the anti-allergic activity of F-GLSP with unfermented Gracilaria lemaneiformis polysaccharides (UF-GLSP), an OVA-induced mouse food allergy model was established. F-GLSP exhibited a significant reduction in OVA-specific IgE and mMCP levels in allergic mice. Moreover, it significantly inhibited Th2 differentiation and IL-4 production and significantly promoted Treg differentiation and IL-10 production in allergic mice. In contrast, UF-GLSP only reduced OVA-specific IgE and mMCP in the serum of allergic mice. Furthermore, F-GLSP demonstrated a more pronounced regulation of intestinal flora abundance compared to UF-GLSP, significantly influencing the populations of Firmicutes, Bacteroidetes, Lactobacillus, and Clostridiales in the intestines of mice with food allergy. These findings suggest that F-GLSP may regulate food allergies in mice through multiple pathways. In summary, this study has promoted further development of functional foods with anti-allergic properties based on red algae polysaccharides.

Dietary nobiletin regulated cefuroxime- and levofloxacin-associated "gut microbiota-metabolism" imbalance and intestinal barrier dysfunction in mice

Nobiletin (NOB) exhibits significant biological activities and may be a potential dietary treatment for antibiotic-associated gut dysbiosis. In this study, mice were gavaged with 0.2 mL day-1 of 12.5 g L-1 cefuroxime (LFX) and 10 g L-1 levofloxacin (LVX) for a duration of 10 days, accompanied by 0.05% NOB to investigate the regulatory effect and potential mechanisms of NOB on antibiotic-induced intestinal microbiota disorder and intestinal barrier dysfunction. Our results indicated that dietary NOB improved the pathology of intestinal epithelial cells and the intestinal permeability by upregulating the expression of intestinal tight junction proteins (TJs) and the number of goblet cells. Furthermore, dietary NOB reduced the levels of serum lipopolysaccharide (LPS) and pro-inflammatory factors (TNF-α and IL-1β), thereby facilitating the restoration of the intestinal mucosal barrier. Additionally, dietary NOB increased the abundance of beneficial bacteria f_Lachnospiraceae and regulated the metabolic disorders of short-chain fatty acids (SCFAs) and bile acids (BAs). Notably, NOB supplementation resulted in elevated levels of butyric acid and lithocholic acid (LCA), which contributed to the repair of the intestinal mucosal barrier function and the maintenance of intestinal homeostasis. Collectively, our results propose a healthy dietary strategy for the prevention or mitigation of antibiotic-associated gut dysbiosis by dietary NOB.

Effect of Cordyceps militaris Powder Prophylactic Supplementation on Intestinal Mucosal Barrier Impairment and Microbiota-Metabolites Axis in DSS-Injured Mice

Ulcerative colitis (UC) is a chronic and recurrent inflammatory disease with an unknown pathogenesis and increasing incidence. The objective of this study is to investigate the impact of prophylactic treatment with Cordyceps militaris on UC. The findings demonstrate that prophylactic supplementation of C. militaris powder effectively mitigates disease symptoms in DSS-injured mice, while also reducing the secretion of pro-inflammatory cytokines. Furthermore, C. militaris powder enhances the integrity of the intestinal mucosal barrier by up-regulating MUC2 protein expression and improving tight junction proteins (ZO-1, occludin, and claudin 1) in DSS-injured mice. Multiomics integration analyses revealed that C. militaris powder not only reshaped gut microbiota composition, with an increase in Lactobacillus, Odoribacter, and Mucispirillum, but also exerted regulatory effects on various metabolic pathways including amino acid, glyoxylates, dicarboxylates, glycerophospholipids, and arachidonic acid. Subsequent analysis further elucidated the intricate interplay of gut microbiota, the intestinal mucosal barrier, and metabolites, suggesting that the microbiota-metabolite axis may involve the effect of C. militaris on intestinal mucosal barrier repair in UC. Moreover, in vitro experiments demonstrated that peptides and polysaccharides, derived from C. militaris, exerted an ability to change the gut microbiota structure of UC patients' feces, particularly by promoting the growth of Lactobacillus. These findings suggest that regulatory properties of C. militaris on gut microbiota may underlie the potential mechanism responsible for the protective effect of C. militaris in UC. Consequently, our study will provide support for the utilization of C. militaris as a whole food-based ingredient against the occurrence and development of UC.

Polysaccharides from Tetrastigma Hemsleyanum Diels et Gilg ameliorated inflammatory bowel disease by rebuilding the intestinal mucosal barrier and inhibiting inflammation through the SCFA-GPR41/43 signaling pathway

In this study, the therapeutic effects of Tetrastigma hemsleyanum polysaccharide (THP) on inflammatory bowel disease (IBD) and its possible mechanisms were investigated based on the IBD mouse model induced by dextran sodium sulfate (DSS) and the lipopolysaccharide (LPS)-stimulated Caco-2 cell model. THP significantly alleviated the signs and symptoms of DSS-induced IBD mice, including the reduced weight, shortened colonic length, and increased colitis disease activity index. In vivo, THP significantly reduced inflammatory cell infiltration and oxidative damage, promoted intestinal mucus secretion, and restored the integrity of the intestinal epithelial barrier and mucus barrier. Furthermore, THP reversed the changes in the intestinal flora of colonized mice and restored the levels of short-chain fatty acids (SCFAs) by increasing the abundance of potentially beneficial bacteria and increasing the abundance of butyrate-producing bacteria. In addition, THP upregulated the expression of G-protein-coupled receptors (GPR41 and GPR43) both in vivo and in vitro. In summary, the current investigation showed that THP effectively protected against intestinal inflammation and impairment in the intestinal barrier in the setting of DSS-induced IBD, possibly by regulating gut microbiota structure and corresponding SCFA metabolites, and the pathway of SCFAs action may be related to SCFA-GPR41/43 signaling pathway.

Inhibitory effect of Portulaca oleracea L. aqueous extract and juice on NLRP3 inflammasome activation in an ulcerative colitis mouse model

Portulaca oleracea L. (PO) is an edible and medicinal plant used for treating gastrointestinal diseases. However, the effects of PO on ulcerative colitis (UC) and underlying mechanisms remain unclear. This study investigated the effects of PO aqueous extract (POE) and PO juice (PJ) on dextran sulfate sodium (DSS)-induced UC in a mouse model and attempted to unravel their underlying mechanisms. The results revealed that PJ contains more bioactive compounds and has more overlapping targets with UC than POE. Both POE and PJ effectively reduced Disease Activity Index scores and inflammatory cell infiltration in the UC mouse model, but PJ had a better effect than POE. Furthermore, PJ inhibited pyroptosis by decreasing the expression of the NLRP3 inflammasome, while also repairing the dysfunction of the intestinal barrier by upregulating the expression of tight junction proteins. Therefore, based on the study findings, we concluded that PJ can improve DSS-induced UC and may suppress pyroptosis by interfering with the activation of the NLRP3 inflammasome.

Plant-Based Dietary Fibers and Polysaccharides as Modulators of Gut Microbiota in Intestinal and Lung Inflammation: Current State and Challenges

Recent research has underscored the significant role of gut microbiota in managing various diseases, including intestinal and lung inflammation. It is now well established that diet plays a crucial role in shaping the composition of the microbiota, leading to changes in metabolite production. Consequently, dietary interventions have emerged as promising preventive and therapeutic approaches for managing these diseases. Plant-based dietary fibers, particularly polysaccharides and oligosaccharides, have attracted attention as potential therapeutic agents for modulating gut microbiota and alleviating intestinal and lung inflammation. This comprehensive review aims to provide an in-depth overview of the current state of research in this field, emphasizing the challenges and limitations associated with the use of plant-based dietary fibers and polysaccharides in managing intestinal and lung inflammation. By shedding light on existing issues and limitations, this review seeks to stimulate further research and development in this promising area of therapeutic intervention.