Dietary Tangeretin Alleviated Dextran Sulfate Sodium-Induced Colitis in Mice via Inhibiting Inflammatory Response, Restoring Intestinal Barrier Function, and Modulating Gut Microbiota

Soluble Dietary Fiber from Fermentation of Tea Residues by Eurotium cristatum and the Effects on DSS-Induced Ulcerative Colitis

Tea residues are rich in dietary fiber, most of which are insoluble dietary fiber (IDF). However, soluble dietary fiber (SDF) is reported to show a better health-promoting effect. In this paper, the Eurotium cristatum (E. cristatum) fermentation method was employed to prepare SDF from tea residues. The results showed that the yield of SDF in fermented SDF (FSDF) was higher than that in unfermented SDF (USDF). Meanwhile, an increased proportion of galactose and a looser microstructure were observed in FSDF. In addition, FSDF has more advantages than USDF in relieving colitis symptoms. FSDF is more effective in reversing weight loss, colon shortening, and tissue damage. Meanwhile, it has a better regulatory effect on the level of inflammatory factors (IL-6, IL-1β, TNF-α, and IL-10) and oxidative stress (CAT, T-SOD, and MDA). FSDF treatment more effectively restored gut microbiota composition toward normal parameters compared to USDF by upregulating Akkermanisa and Lachospiracae_NK4A136_group and downregulating Helicobacter and Alisitipes. In conclusion, fermentation treatment with E. cristatum contributed to the preparation efficiency and bioactive effect of SDF from tea residues. This study will provide a theoretical basis for the development and utilization of tea residues.

Dynamics of chemical profile and microbial community in 3 consecutive years reveal Rhodococcus and Apiotrichum are potential microbes contributing to quality formation of Guang Chenpi

Currently, there remains a debate regarding the functional microorganisms responsible for the quality formation of Guang Chenpi (GCP). Thus, the metabolite profiles and microbial diversity of GCP samples subjected to natural treatment versus those sterilized via electron beam irradiation were investigated over a three-year period. It was found the main constituents of GCP were influenced both by spontaneous changes and microbial activity. In naturally treated GCP, we revealed a decrease in volatile components like terpenoids, alongside variations in flavonoid content. After 36 months of storage, there was a significant increase in hesperitin content (0.084-0.103 mg/g), while nobiletin content exhibited a marked decrease (7.294-2.825 mg/g). Microbial community succession can be categorized into four distinct stages based on storage duration, with Rhodococcus and Apiotrichum emerging as the predominant microbial genera (>35 %) at the 36-month mark. These two taxon were thought to be potential microbial organisms contributing to the chemical transformations in GCP.

Mung Bean Peptides Alleviate Dextran-Sulfate-Sodium-Induced Colitis Symptoms in Mice by Protecting the Intestinal Mechanical Barrier and Regulating Gut Microbiota

Ulcerative colitis (UC), an idiopathic and recurrent ailment, substantially influences a patient's health. Mung bean peptides (MBPs) are bioactive substances derived from mung bean protein that possess notable anti-inflammatory properties. However, their efficacy and underlying mechanisms in UC treatment remain unclear. In this study, the structural characteristics of MBPs were examined by determining various parameters, such as amino acid composition, molecular weight distribution, and peptide sequences, thereby structurally demonstrating their anti-inflammatory potential. The therapeutic effectiveness of MBPs in UC treatment was evaluated by assessing its influence on colon length, histological damage to colonic tissue, and disease activity index of mice suffering from colitis induced by dextran sulfate sodium (DSS). Additionally, the study explored the potential mechanism of action of MBPs in UC by analyzing the intestinal microbiota, inflammatory cytokines in serum, and tight junction (TJ) proteins in the colon tissue of mice. The results revealed that MBPs significantly increased colon length, reduced colonic tissue damage, and decreased the disease activity index in mice with UC. MBPs restored intestinal barrier function by upregulating the expression of ZO-1 and claudin-1 proteins within the colonic tissue of mice with DSS-induced colitis, thereby treating UC. MBPs exerted anti-inflammatory effects by downregulating the amplification of inflammatory cytokines in the serum, improving the gut microbiota structure in mice with colitis, and regulating immune-related signaling pathways. Therefore, there is an experimental basis for the potential use of MBPs as adjunctive therapy in UC.

Investigating the interaction between tangeretin metabolism and amelioration of gut microbiota disorders using dextran sulfate sodium-induced colitis and antibiotic-associated diarrhea models

Dysregulation of gut microbiota homeostasis can lead to various health issues. In this study, we investigated the effects of tangeretin (TAN) on gut microbiota homeostasis in a mouse model (C57BL/6J) of disease, specifically focusing on dextran sulfate sodium (DSS)-induced colitis and antibiotic-associated diarrhea through in vitro fermentation of intestinal bacteria. Our results demonstrated that TAN effectively improved the diversity and structure of the disordered microbiota, increasing the levels of beneficial bacteria such as Lachnospiraceae and Bacteroidaceae, while decreasing harmful bacteria such as Enterococcaceae and Pseudomonadaceae. Additionally, TAN enhanced the production of short-chain fatty acids (SCFAs) in disordered microbial communities. Moreover, the metabolism of TAN by intestinal microorganisms yielded two new metabolites, which exhibited an inverse-conjugate (deconjugate) role, leading to the production of more functional substances with high bioactivity. These findings provide a scientific basis for the potential use of TAN as a prebiotic to regulate intestinal microbiota.

Promotion of Healthy Aging Through the Nexus of Gut Microbiota and Dietary Phytochemicals

Aging is associated with the decline of tissue and cellular functions, which can promote the development of age-related diseases like cancer, cardiovascular disease, neurodegeneration, and disorders of the musculoskeletal and immune systems. Healthspan is the length of time an individual is in good health and free from chronic diseases and disabilities associated with aging. Two modifiable factors that can influence healthspan, promote healthy aging, and prevent the development of age-related diseases, are diet and microbiota in the gastrointestinal tract (gut microbiota). This review will discuss how dietary phytochemicals and gut microbiota can work in concert to promote a healthy gut and healthy aging. First, an overview is provided of how the gut microbiota influences healthy aging through its impact on gut barrier integrity, immune function, mitochondria function, and oxidative stress. Next, the mechanisms by which phytochemicals effect gut health, inflammation, and nurture a diverse and healthy microbial composition are discussed. Lastly, we discuss how the gut microbiota can directly influence health by producing bioactive metabolites from phytochemicals in food like urolithin A, equol, hesperetin, and sulforaphane. These and other phytochemical-derived microbial metabolites that may promote healthspan are discussed. Importantly, an individual's capacity to produce health-promoting microbial metabolites from cruciferous vegetables, berries, nuts, citrus, and soy products will be dependent on the specific bacteria present in the individual's gut.

Microbes: Drivers of Chenpi manufacturing, biotransformation, and physiological effects

Chenpi holds a rich history of both edible and medicinal applications worldwide, garnering increased attention from researchers in recent years due to its diverse physiological effects. While current research predominantly exploresed its chemical composition and physiological effects, there remains a notable gap in knowledge concerning its manufacturing, characteristic chemical substances, and the underlying mechanisms driving its physiological effects. In this review, the impacts of microbes on the manufacturing, biotransformation, and physiological effects of Chenpi were summarized, as well as the present status of product development. Furthermore, this review engaged in an in-depth discussion highlighting the challenges and shortcomings in recent research, while proposing potential directions and prospects. Additionally, the claim that "The longer the aging, the better the quality" of Chenpi was scientifically evaluated for the first time, providing a solid theoretical foundation for advancing the Chenpi industry.

Structural Characterization of Water-Soluble Pectin from the Fruit of Diospyros lotus L. and Its Protective Effects against DSS-Induced Colitis in Mice

Polysaccharides from Diospyros lotus L. were investigated for their structural characterization and anti-inflammatory activity. Four low polymer dispersity index (PDI) subfractions were obtained: DRP-1 (153.95 kDa), DRP-2 (61.22 kDa), DRP-3 (22.80 kDa), and DRP-4 (8.93 kDa), respectively. DRP-4 contained the highest number of RG-I domains (43.25%), while DRP-1 had the highest degree of methyl esterification (37.5%). Results from the dextran sulfate sodium (DSS) salt-induced ulcerative colitis (UC) mice model indicated that DCP promoted mucosal and tight junction protein (caudin-1 and occludin) expression. Moreover, DCP improved the microbial community composition through selective enrichment of beneficial bacteria such as Lachnospiraceae and Lactobacillaceae. The anti-inflammatory activity of DCP was speculated to be related to its neutral sugar side chain and low esterification degree. These results suggested that DCP could prevent DSS-induced colitis and inhibit colon inflammation by maintaining a balanced gut microbiome and protecting the colon mucosal barrier.

Lactobacillus acidophilus 6074 Fermented Jujube Juice Ameliorated DSS-induced Colitis via Repairing Intestinal Barrier, Modulating Inflammatory Factors, and Gut Microbiota

Lactobacillus acidophilus L. acidophilus Lactobacillus, Bifidobacterium, and Akkermansia, This study aimed to explore the ameliorative effects and underlying mechanisms of oral administration Lactobacillus acidophilus 6074 fermented jujube juice (LAFJ) on dextran sulfate sodium (DSS)-induced colitis in mice. In this study, jujube juice was used as a substrate and fermented by L. acidophilus 6074 to investigate its effects on gut microbiota, intestinal barrier function, oxidative stress, inflammatory factors, and short-chain fatty acids (SCFAs) in mice with colitis and to reveal its potential mechanism for alleviating colitis. The results demonstrated that fermentation caused significant changes in the nutrients and nonnutrients of jujube juice, mainly in organic acids (malic acid, lactic acid, citric acid, and succinic acid) and free amino acids (Thr, Met, Ser, Ile, and Lys). High-dose LAFJ (20 mL/kg/day) significantly reduced the disease activity index (DAI), improved histopathological morphology, and increased colon length in colitis mice. LAFJ alleviated colon damage and preserved the integrity of the colonic mucosal barrier by promoting the expression of colonic tight junction proteins occludin, claudin-1, and zonula occluden-1 (ZO-1). Furthermore, LAFJ inhibited the production of proinflammatory factors and attenuated oxidative stress. Gut microbiota of mice revealed that LAFJ increased beneficial bacteria such as Lactobacillus, Bifidobacterium, and Akkermansia, promoted the production of SCFAs, and inhibited the growth of harmful microorganisms. Overall, LAFJ could reshape and restore gut microbiota imbalance caused by intestinal inflammation and alleviate the development of colitis, which may become a novel dietary intervention.

Effects of Flavonoids in Fructus Aurantii Immaturus on Carcass Traits, Meat Quality and Antioxidant Capacity in Finishing Pigs

This experiment aimed to explore the effects of flavonoids in Fructus Aurantii Immaturus (FFAI) on carcass traits, meat quality, and the antioxidant capacity of finishing pigs. The results indicated that the addition of an appropriate amount of FFAI into their diet could significantly reduce the backfat thickness and perirenal fat percentage of finishing pigs, as well as the drip loss, water-holding capacity, shear force, and the levels of lactate, glucose-6-phosphate, glucose, ATP, phosphofructokinase, and pyruvate in the longissimus dorsi (LD) muscle. It also elevated the levels of flavor amino acids such as glutamate, serine, and threonine, and enriched the composition of flavor substances, including benzene and octanal, which significantly contributed to the enhancement of pork flavor. Furthermore, it enhanced the expression levels of MyHC I and MyHC IIa. In summary, the appropriate addition of FFAI to the diet could improve the carcass traits, meat quality, and antioxidant capacity of finishing pigs. The optimal level of FFAI supplementation is 0.12%.

Novel selenium-enriched Pichia kudriavzevii as a dietary supplement to alleviate dextran sulfate sodium-induced colitis in mice by modulating the gut microbiota and host metabolism

Inflammatory bowel disease (IBD) poses persistent challenges due to its chronic and recurrent nature, exacerbated by the unsatisfactory outcomes of the traditional treatment approaches. In this study, we developed a dietary supplement, selenium-enriched Pichia kudriavzevii (SeY), to alleviate dextran sulfate sodium-induced colitis in mice. The newly developed functional food shows dual-functional activity, acting both as a probiotic and a reliable source of organic selenium. This study aimed to investigate the preventive effects of SeY against dextran sulfate sodium-induced colitis in mice and elucidate the underlying mechanisms. Results showed that SeY, especially at high doses (HSeY), significantly ameliorated colitis symptoms, reduced colonic damage, attenuated inflammatory responses, and mitigated oxidative stress. Furthermore, HSeY strengthened intestinal barrier function by increasing goblet cell numbers, upregulating MUC2 expression, and enhancing tight junction proteins (ZO-1, claudin-1, and occludin). Additionally, HSeY alleviated gut microbiota dysbiosis by promoting the colonization of beneficial bacteria such as norank-f-Muribaculaceae and Bacteroides, while suppressing harmful microorganisms such as norank-f-norank-o-Clostridia-UCG-014. The altered gut microbiota also affected gut metabolism, with differential metabolites primarily associated with amino acids, such as tryptophan metabolism, contributing to the mitigation of oxidative stress and inflammatory responses. Further studies involving antibiotic-mediated depletion of gut flora and fecal microbiota transfer trials corroborated that the preventive effect of HSeY against IBD relied on the gut microbiota. This study provides vital insights into colitis prevention and advances selenium-enriched fortified food-targeted nutritional interventions.

Morin alleviates DSS-induced ulcerative colitis in mice via inhibition of inflammation and modulation of intestinal microbiota

Ulcerative colitis (UC) is a chronic inflammatory condition with recurrent and challenging symptoms. Effective treatments are lacking, making UC management a critical research area. Morin (MO), a flavonoid from the Moraceae family, shows potential as an anti-UC agent, but its mechanisms are not fully understood. Using a dextran sulfate sodium (DSS)-induced UC mouse model, we employed network pharmacology to predict MO's therapeutic effects. Assessments included changes in body weight, disease activity index (DAI), and colon length. Immunofluorescence, hematoxylin and eosin (H&E), and PAS staining evaluated colon damage. ELISA and western blot analyzed inflammatory factors, tight junction (TJ)-associated proteins (Claudin-3, Occludin, ZO-1), and Mitogen-Activated Protein Kinase (MAPK)/ Nuclear Factor kappa B (NF-κB) pathways. 16S rRNA sequencing assessed gut microbiota diversity, confirmed by MO's modulation via Fecal Microbial Transplantation (FMT). Early MO intervention reduced UC severity by improving weight, DAI scores, and colon length, increasing goblet cells, enhancing barrier function, and inhibiting MAPK/NF-κB pathways. MO enriched gut microbiota, favoring beneficial bacteria like Muribaculaceae and Erysipelotrichaceae while reducing harmful Erysipelotrichaceae and Muribaculaceae. This study highlights MO's potential in UC management through inflammation control, mucosal integrity maintenance, and gut flora modulation.

Camel milk polar lipids ameliorate dextran sulfate sodium-induced colitis in mice by modulating the gut microbiota

Milk contains abundant polar lipids, which are vital constituents of biological membranes. These polar lipids are present in the human diet as phospholipids and sphingolipids. Nevertheless, the limited focus has been on the attributes and role of camel milk polar lipids (MPL). In this study, camel MPL were isolated, and the composition of their lipidome was determined using ultra-high-performance liquid chromatography-tandem MS. This study characterized a total of 333 polar lipids, which encompassed glycerophospholipids and sphingolipids. Camel milk is rich in polar lipids, mainly phosphatidylethanolamine, sphingomyelin, and phosphatidylcholine. The results indicated that MPL intervention relieved the clinical symptoms and colon tissue damage in mice with dextran sulfate sodium-induced colitis, along with suppressing the expression of proinflammatory cytokines. Moreover, the administration of MPL partially alleviated mouse gut microbiota dysbiosis by increasing the abundance of probiotics (such as Lachnospiraceae_NK4A136_group and Muribaculaceae) and decreasing the number of harmful bacteria (such as Bacteroides and Parabacteroides). This study was conducted to investigate the potent protective effects of MPL in camel milk treatments on a mouse model of colitis and provided new ideas for the application of camel milk.

Dietary rutin improves the antidiarrheal capacity of weaned piglets by improving intestinal barrier function, antioxidant capacity and cecal microbiota composition

BACKGROUND

Early weaning is prone to damage intestinal barrier function, resulting in diarrhea, whereas rutin, as a natural flavonoid with multiple biological functions, shows potential in piglets. Therefore, the effects of dietary rutin on growth, antidiarrheal, barrier function, antioxidant status and cecal microbiota of weaned piglets were investigated with the control group (CON) (basal diet) and Rutin (basal diet+500 mg kg-1 rutin) groups fed for 14 days.

RESULTS

The results showed that dietary 500 mg kg-1 rutin significantly decreased diarrhea index, serum diamine oxidase activity and total aerobic bacterial population in mesenteric lymph nodes, whereas it significantly increased the gain-to-feed ratio (G:F) and serum growth hormone content, jejunal villus height and villus height to crypt depth ratio, and also enhanced jejunal claudin-1 and zonula occludens-1 mRNA and protein expression. Meanwhile, dietary rutin significantly decreased inflammation-associated mRNA expression, malondialdehyde (MDA) content, swollen mitochondrial number and mitochondrial area in the jejunum, whereas it increased the total superoxide dismutase (T-SOD) and glutathione peroxidase activities and activated the Nrf2 signaling pathway. Moreover, dietary rutin significantly increased Firmicutes abundance and decreased Campylobacterota abundance, which were closely associated with the decreased diarrhea index and MDA content or increased Claudin-1 expression and T-SOD activity.

CONCLUSION

Dietary 500 mg kg-1 rutin increased G:F by improving intestinal morphology, and alleviated diarrhea by enhancing intestinal barrier, which might be associated with the enhanced antioxidant capacity via activating the Nrf2/Keap1 signaling pathway and the improved cecal microbial composition in weaned piglets. © 2024 Society of Chemical Industry.

Structural characterization of the glucan from Gastrodia elata Blume and its ameliorative effect on DSS-induced colitis in mice

The polysaccharide glucan was extracted from Gastrodia elata Blume, and its structural characterizations and beneficial effects against acute dextran sulfate sodium (DSS)-induced ulcerative colitis were investigated. The results showed that a polysaccharide GP with a molecular weight of 811.0 kDa was isolated from G. elata Blume. It had a backbone of α-D-1,4-linked glucan with branches of α-d-glucose linked to the C-6 position. GP exhibited protective effects against DSS-induced ulcerative colitis, and reflected in ameliorating weight loss and pathological damages in mice, increasing colon length, inhibiting the expression of inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), decreasing the levels of inflammatory related proteins NLRP3 and ASC, and elevating the anti-inflammatory cytokine interleukin-10 (IL-10) level in mouse colon tissues. GP supplementation also reinforced the intestinal barrier by promoting the expression of ZO-1, Occludin, and MUC2 of colon tissues, and positively regulated intestinal microbiota. Thus, GP treatment possessed a significant improvement in ulcerative colitis in mice, and it was expected to be developed as a functional food.

Matrine Ameliorates DSS-Induced Colitis by Suppressing Inflammation, Modulating Oxidative Stress and Remodeling the Gut Microbiota

Matrine (MT) possesses anti-inflammatory, anti-allergic and antioxidative properties. However, the impact and underlying mechanisms of matrine on colitis are unclear. The purpose of this research was to examine the protective impact and regulatory mechanism of matrine on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice. MT alleviated DSS-induced UC by inhibiting weight loss, relieving colon shortening and reducing the disease activity index (DAI). Moreover, DSS-induced intestinal injury and the number of goblet cells were reversed by MT, as were alterations in the expression of zonula occludens-1 (ZO-1) and occludin in colon. Simultaneously, matrine not only effectively restored DSS-induced oxidative stress in colonic tissues but also reduced the production of inflammatory cytokines. Furthermore, MT could treat colitis mice by regulating the regulatory T cell (Treg)/T helper 17 (Th17) cell imbalance. We observed further evidence that MT alleviated the decrease in intestinal flora diversity, reduced the proportion of Firmicutes and Bacteroidetes, decreased the proportion of Proteobacteria and increased the relative abundance of Lactobacillus and Akkermansia in colitis mice. In conclusion, these results suggest that MT may mitigate DSS-induced colitis by enhancing the colon barrier integrity, reducing the Treg/Th17 cell imbalance, inhibiting intestinal inflammation, modulating oxidative stress and regulating the gut microbiota. These findings provide strong evidence for the development and application of MT as a dietary treatment for UC.

Polyphenols from hickory nut reduce the occurrence of atherosclerosis in mice by improving intestinal microbiota and inhibiting trimethylamine N-oxide production

BACKGROUND

Trimethylamine N-oxide (TMAO), a metabolite produced by intestinal microbiota through metabolizing phosphatidylcholine, choline, l-carnitine and betaine in the diet, has been implicated in the pathogenesis of atherosclerosis (AS). Concurrently, dietary polyphenols have garnered attention for their potential to ameliorate obesity, diabetes and atherosclerosis primarily by modulating the intestinal microbial structure. Hickory (Carya cathayensis) nut, a polyphenol-rich food product favored for its palatability, emerges as a candidate for exploration.

HYPOTHESIS/PURPOSE

The relationship between polyphenol of hickory nut and atherosclerosis prevention will be firstly clarified, providing theoretical basis for the discovery of natural products counteracting TMAO-induced AS process in hickory nut.

STUDY DESIGN AND METHODS

Employing Enzyme-linked Immunosorbent Assay (ELISA) and histological examination of aortic samples, the effects of total polyphenol extract on obesity index, inflammatory index and pathological changes of atherosclerosis in C57BL/6 J mice fed with high-fat and high choline diet were evaluated. Further, the composition, abundance, and function of mouse gut microbiota were analyzed through 16srDNA sequencing. Concurrently, the levels of TMAO and the expression of key enzymes (CutC and FMO3) involved in its synthesis are quantified using ELISA, Western Blot and Real-Time Quantitative PCR (RT-qPCR). Additionally, targeted metabolomic profiling of the hickory nut polyphenol extract was conducted, accompanied by molecular docking simulations to predict interactions between candidate polyphenols and the CutC/FMO3 using Autodock Vina. Finally, the docking prediction were verified by microscale thermophoresis (MST) .

RESULTS

Polyphenol extracts of hickory nut improved the index of obesity and inflammation, and alleviated the pathological changes of atherosclerosis in C57BL/6 J mice fed with high-fat and high-choline diet. Meanwhile, these polyphenol extracts also changed the composition and function of intestinal microbiota, and increased the abundance of microorganisms in mice. Notably, the abundance of intestinal microbiota endowed with CutC gene was significantly reduced, coherent with expression of CutC catalyzing TMA production. Moreover, polyphenol extracts also decreased the expression of FMO3 in the liver, contributing to the reduction of TMAO levels in serum. Furthermore, metabonomic profile analysis of these polyphenol extracts identified 647 kinds of polyphenols. Molecular docking predication further demonstrated that Casuariin and Cinnamtannin B2 had the most potential inhibition on the enzymatic activities of CutC or FMO3, respectively. Notably, MST analysis corroborated the potential for direct interaction between CutC enzyme and available polyphenols such as Corilagin, (-)-Gallocatechin gallate and Epigallocatechin gallate.

CONCLUSION

Hickory polyphenol extract can mitigate HFD-induced AS by regulating intestinal microflora in murine models. In addition, TMA-FMO3-TMAO pathway may play a key role in this process. This research unveils, for the inaugural time, the complex interaction between hickory nut-derived polyphenols and gut microbial, providing novel insights into the role of dietary polyphenols in AS prevention.

S/O/W Emulsion with CAPE Ameliorates DSS-Induced Colitis by Regulating NF-κB Pathway, Gut Microbiota and Fecal Metabolome in C57BL/6 Mice

Inflammatory bowel disease (IBD) has attracted much attention worldwide due to its prevalence. In this study, the effect of a solid-in-oil-in-water (S/O/W) emulsion with Caffeic acid phenethyl ester (CAPE, a polyphenolic active ingredient in propolis) on dextran sulfate sodium (DSS)-induced colitis in C57BL/6 mice was evaluated. The results showed that CAPE-emulsion could significantly alleviate DSS-induced colitis through its effects on colon length, reduction in the disease activity index (DAI), and colon histopathology. The results of ELISA and Western blot analysis showed that CAPE-emulsion can down-regulate the excessive inflammatory cytokines in colon tissue and inhibit the expression of p65 in the NF-κB pathway. Furthermore, CAPE-emulsion promoted short-chain fatty acids production in DSS-induced colitis mice. High-throughput sequencing results revealed that CAPE-emulsion regulates the imbalance of gut microbiota by enhancing diversity, restoring the abundance of beneficial bacteria (such as Odoribacter), and suppressing the abundance of harmful bacteria (such as Afipia, Sphingomonas). The results of fecal metabolome showed that CAPE-emulsion restored the DSS-induced metabolic disorder by affecting metabolic pathways related to inflammation and cholesterol metabolism. These research results provide a scientific basis for the use of CPAE-emulsions for the development of functional foods for treating IBD.

Anti-inflammatory probiotics HF05 and HF06 synergistically alleviate ulcerative colitis and secondary liver injury

Given the limited efficacy and adverse effects associated with conventional drugs, probiotics are emerging as a promising therapeutic strategy for mitigating the chronic nature of ulcerative colitis (UC) and its consequential secondary liver injury (SLI). Limosilactobacillus fermentum HF06 and Lactiplatibacillus plantarum HF05 are strains we screened with excellent anti-inflammatory and probiotic properties in vitro. In this study, the intervention of HF06 and HF05 in combination (MIXL) was found to be more effective in alleviating intestinal inflammation and secondary liver injury in UC mice compared to supplementing with the two strains individually. Results demonstrated that MIXL effectively attenuated colon shortening and weight loss, downregulated the expression of pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 mRNA in the intestines, mitigated SLI, and augmented the enzymatic activities of SOD, CAT, and GSH-Px in the liver. MIXL enhances the intestinal barrier in UC mice, regulates the structure and composition of the gut microbiota, promotes the abundance of Lactobacillus, and suppresses the abundance of bacteria associated with inflammation and liver injury, including Clostridium_Sensu_Stricto_1, Escherichia, Shigella, Enterococcus, Corynebacterium, Desulfovibrio, and norank_f__Oscillospiraceae. This study demonstrated the synergistic effect of HF06 and HF05, providing a reliable foundation for the alleviation of UC.

A Probiotic Targets Bile Acids Metabolism to Alleviate Ulcerative Colitis by Reducing Conjugated Bile Acids

SCOPE

Gut microbiota (GM) dysbiosis and dysregulated bile acids (BAs) metabolism have been linked to ulcerative colitis (UC) pathogenesis. The possibility of utilizing live probiotics with a defined BAs-metabolizing capability to modify the composition BAs for UC treatment remains unexplored.

METHODS AND RESULTS

In this study, Strain GR-4 is sourced from traditional Chinese fermented food, "Jiangshui," and demonstrated the ability to deconjugate two common conjugated BAs by over 69% and 98.47%, respectively. It administers strain GR-4 to dextran sulfate sodium (DSS)-induced UC mice, and observes an overall alleviation of UC symptoms, as evidence by improved colon morphology, reduces inflammation and oxidative stress, and restores intestinal barrier function. Importantly, these effects are reliant on an intact commensal microbiota, as depletion of GM mitigated GR-4s efficacy. Metabolomics analysis unveils a decline in conjugated BAs and an increase in secondary BAs following GR-4 administration. GM analysis indicates that GR-4 selectively enriches bacterial taxa linked to BAs metabolism, enhancing GM's capacity to modify BAs.

CONCLUSION

This research demonstrates the potential for natural fermented foods and probiotics to effectively manipulate BAs composition, including conjugated and secondary BAs, to alleviate UC symptoms, underscoring the benefits of these approaches for gut health.

Resistant Starch from Purple Sweet Potatoes Alleviates Dextran Sulfate Sodium-Induced Colitis through Modulating the Homeostasis of the Gut Microbiota

Ulcerative colitis (UC) is a complicated inflammatory disease with a continually growing incidence. In this study, resistant starch was obtained from purple sweet potato (PSPRS) by the enzymatic isolation method. Then, the structural properties of PSPRS and its protective function in dextran sulfate sodium (DSS)-induced colitis were investigated. The structural characterization results revealed that the crystallinity of PSPRS changed from CA-type to A-type, and the lamellar structure was totally destroyed during enzymatic hydrolysis. Compared to DSS-induced colitis mice, PSPRS administration significantly improved the pathological phenotype and colon inflammation in a dose-dependent manner. ELISA results indicated that DSS-induced colitis mice administered with PSPRS showed higher IL-10 and IgA levels but lower TNF-α, IL-1β, and IL-6 levels. Meanwhile, high doses (300 mg/kg) of PSPRS significantly increased the production of acetate, propionate, and butyrate. 16S rDNA high-throughput sequencing results showed that the ratio of Firmicutes to Bacteroidetes and the potential probiotic bacteria levels were notably increased in the PSPRS treatment group, such as Lactobacillus, Alloprevotella, Lachnospiraceae_NK4A136_group, and Bifidobacterium. Simultaneously, harmful bacteria like Bacteroides, Staphylococcus, and Akkermansia were significantly inhibited by the administration of a high dose of PSPRS (p < 0.05). Therefore, PSPRS has the potential to be a functional food for promoting intestinal health and alleviating UC.

Amygdalin Alleviates DSS-Induced Colitis by Restricting Cell Death and Inflammatory Response, Maintaining the Intestinal Barrier, and Modulating Intestinal Flora

Inflammatory bowel disease (IBD) refers to a cluster of intractable gastrointestinal disorders with an undetermined etiology and a lack of effective therapeutic agents. Amygdalin (Amy) is a glycoside extracted from the seeds of apricot and other Rosaceae plants and it exhibits a wide range of pharmacological properties. Here, the effects and mechanisms of Amy on colitis were examined via 16S rRNA sequencing, ELISA, transmission electron microscopy, Western blot, and immunofluorescence. The results showed that Amy administration remarkably attenuated the signs of colitis (reduced body weight, increased disease activity index, and shortened colon length) and histopathological damage in dextran sodium sulfate (DSS)-challenged mice. Further studies revealed that Amy administration significantly diminished DSS-triggered gut barrier dysfunction by lowering pro-inflammatory mediator levels, inhibiting oxidative stress, and reducing intestinal epithelial apoptosis and ferroptosis. Notably, Amy administration remarkably lowered DSS-triggered TLR4 expression and the phosphorylation of proteins related to the NF-κB and MAPK pathways. Furthermore, Amy administration modulated the balance of intestinal flora, including a selective rise in the abundance of S24-7 and a decline in the abundance of Allobaculum, Oscillospira, Bacteroides, Sutterella, and Shigella. In conclusion, Amy can alleviate colitis, which provides data to support the utility of Amy in combating IBD.

Dietary flavonoids-microbiota crosstalk in intestinal inflammation and carcinogenesis

Colorectal cancer (CRC) is currently the third leading cancer and commonly develops from chronic intestinal inflammation. A strong association was found between gut microbiota and intestinal inflammation and carcinogenic risk. Flavonoids, which are abundant in vegetables and fruits, can inhibit inflammation, regulate gut microbiota, protect gut barrier integrity, and modulate immune cell function, thereby attenuating colitis and preventing carcinogenesis. Upon digestion, about 90% of flavonoids are transported to the colon without being absorbed in the small intestine. This phenomenon increases the abundance of beneficial bacteria and enhances the production of short-chain fatty acids. The gut microbe further metabolizes these flavonoids. Interestingly, some metabolites of flavonoids play crucial roles in anti-inflammation and anti-tumor effects. This review summarizes the modulatory effect of flavonoids on gut microbiota and their metabolism by intestinal microbe under disease conditions, including inflammatory bowel disease, colitis-associated cancer (CAC), and CRC. We focus on dietary flavonoids and microbial interactions in intestinal mucosal barriers as well as intestinal immune cells. Results provide novel insights to better understand the crosstalk between dietary flavonoids and gut microbiota and support the standpoint that dietary flavonoids prevent intestinal inflammation and carcinogenesis.

Limosilactobacillus fermentum HF06-derived paraprobiotic and postbiotic alleviate intestinal barrier damage and gut microbiota disruption in mice with ulcerative colitis

BACKGROUND

Paraprobiotics and postbiotics have shown potential in the treatment of ulcerative colitis (UC). However, their in vivo application is still in its infancy and their mechanisms of action are not well understood.

RESULTS

Here, we investigated the mitigation effects of Limosilactobacillus fermentum HF06-derived paraprobiotic (6-PA) and postbiotic (6-PS) on dextran sulfate sodium induced UC and the potential mechanisms. Results indicated that the administration of 6-PA and 6-PS resulted in the inhibition of weight loss and colon shortening in mice with UC. Furthermore, they led to a significant reduction in both fecal moisture content and the levels of proinflammatory cytokines and oxidative stress in the intestine of the mice. 6-PA and 6-PS treatment strengthened the intestinal mucosal barrier by dramatically upregulating the levels of zonula occludens-1 and occludin proteins. In addition, 6-PA and 6-PS restored intestinal dysbiosis by regulating abundances of certain bacteria, such as Bifidobacterium, Faecalibaculum, Muribaculaceae, Corynebacterium, Escherichia-Shigella and Clostridium_sensu_stricto_1, and regulated the level of short-chain fatty acids.

CONCLUSION

These findings illustrated for the first time that L. fermentum HF06-derived paraprobiotic and postbiotic enhanced the intestinal barrier function, and restored gut microbiota alterations. © 2023 Society of Chemical Industry.

Oral Troxerutin Alleviates Depression Symptoms in Mice by Modulating Gut Microbiota and Microbial Metabolism

SCOPE

A growing body of evidence suggests that the harmful gut microbiota in depression patients can play a role in the progression of depression. There is limited research on troxerutin's impact on the central nervous system (CNS), especially in depression. The study finds that troxerutin effectively alleviates depression and anxiety-like behavior in mice by increasing the abundance of beneficial bacteria like Lactobacillus and Firmicutes while decreasing the abundance of harmful bacteria like Proteobacteria, Bacteroides, and Actinobacteria in the gut. Furthermore, the research reveals that troxerutin regulates various metabolic pathways in mice, including nucleotide metabolism, caffeine metabolism, purine metabolism, arginine biosynthesis, histidine metabolism, 2-oxocarboxylic acid metabolism, biosynthesis of amino acids, glycine, serine and threonine metabolism, and Arginine and proline metabolism.

CONCLUSIONS

In conclusion, the study provides compelling evidence for the antidepressant efficacy of troxerutin. Through the investigation of the role of intestinal microorganisms and metabolites, the study identifies these factors as key players in troxerutin's ability to prevent depression. Troxerutin achieves its neuroprotective effects and effectively prevents depression and anxiety by modulating the abundance of gut microbiota, including Proteobacteria, Bacteroides, and Actinobacteria, as well as regulating metabolites such as creatine.

Tangeretin Attenuates Cerebral Ischemia-Reperfusion-Induced Neuronal Pyroptosis by Inhibiting AIM2 Inflammasome Activation via Regulating NRF2

Pyroptosis is closely involved in the pathopoiesis of cerebral ischemia and reperfusion (I/R) injury which seriously dangers human's life. Studies report that tangeretin (TANG), which is enriched in the peel of Citrus reticulata, has neuroprotective effects. Here, we explored whether absent in melanoma 2 (AIM2) inflammasome-mediated pyroptosis is involved in the cerebral I/R injury and the protective mechanism of TANG against cerebral I/R injury. In this study, we found that TANG treatment effectively alleviated I/R-induced brain injury and inhibited neuronal pyroptosis in an in vivo mice model with middle cerebral artery occlusion/reperfusion (MCAO/R) injury and in an in vitro hippocampal HT22 cell model with oxygen-glucose deprivation and reoxygenation (OGD/R) injury. Furthermore, we found TANG inhibited cerebral I/R-induced neuronal AIM2 inflammasome activation in vivo and in vitro via regulating nuclear factor E2-related factor 2 (NRF2). Moreover, administration of ML385, a chemical inhibitor of NRF2, notably blocked the neuroprotective effects of TANG against cerebral I/R injury. In conclusion, TANG attenuates cerebral I/R-induced neuronal pyroptosis by inhibiting AIM2 inflammasome activation via regulating NRF2. These findings indicate TANG is a potential therapeutic agent for cerebral I/R injury.

Soluble dietary fibers from solid-state fermentation of wheat bran by the fungus Cordyceps cicadae and their effects on colitis mice

Ulcerative colitis is a chronic inflammatory disease with a complex pathogenesis for which there is no definitive therapeutic agent. Fermentation, as a green and efficient bioprocessing technique, has been shown to enhance the biological activity of food ingredients. Soluble dietary fiber isolated from plants is thought to have the potential to prevent and alleviate ulcerative colitis. This work was designed to study the differences in the chemical properties of the soluble dietary fiber from wheat bran fermented by Isaria cicadae Miq. (FSDF) and the unfermented soluble dietary fiber from wheat bran (UFSDF) and their effects on colitis mice. The results showed that FSDF and UFSDF differed in molecular weight, monosaccharide compositions, and surface morphology. In addition, supplementation with UFSDF and FSDF ameliorated the symptoms of DSS-induced colitis in mice by attenuating body weight loss, decreasing the disease activity index and splenic index, shortening the length of the colon, and attenuating colonic tissue damage. UFSDF and FSDF also increased the production of the anti-inflammatory cytokine IL-10 and inhibited the expression of IL-6, IL-1β, and TNF-α. The results of gut flora and short-chain fatty acid analyses showed that UFSDF and FSDF improved the diversity of gut microbiota, up-regulated the abundance of some beneficial bacteria such as Akkermansia and Muribaculaceae, increased the levels of acetic acid, propionic acid, and butyric acid, and restored dextran sodium sulfate (DSS)-induced dysbiosis of the intestinal flora in mice. These findings provide guidance for the development of FSDF and UFSDF as functional foods for the relief of ulcerative colitis.

Dietary tangeretin improved antibiotic-associated diarrhea in mice by enhancing the intestinal barrier function, regulating the gut microbiota, and metabolic homeostasis

Antibiotic-associated diarrhea is mediated by antibiotic treatment and is usually caused by the disruption of the intestinal barrier, gut microbiota, and metabolic balance. To identify a dietary strategy that can mitigate the side effects of antibiotics, this study investigated the effect of tangeretin on antibiotic-associated diarrhea in C57BL/6 mice. The results revealed that dietary tangeretin significantly ameliorated symptoms of antibiotic-associated diarrhea, as evidenced by the decreased diarrhea status scores, the reduced fecal water content, the decreased caecum/body weight ratio, and the alleviated colonic tissue damage. Dietary tangeretin also exhibited a protective effect on the intestinal barrier function by upregulating the mRNA and protein expression of claudin-1 and ZO-1. Furthermore, analysis of the gut microbiota using 16S rRNA gene sequencing indicated that dietary tangeretin modulated the gut microbiota of mice with antibiotic-associated diarrhea via increasing the gut microbiota diversity and the abundance of beneficial bacteria, e.g., Lactobacillaceae and Ruminococcaceae, and decreasing the abundance of harmful bacteria, e.g., Enterococcus and Terrisporobacter. Additionally, dietary tangeretin restored the levels of short-chain fatty acids and modulated metabolic pathways by enriching purine metabolism, bile acid metabolism, ABC transporters, and choline metabolism in cancer. Collectively, these findings provide a solid scientific basis for the rational use of tangeretin as a preventive and therapeutic agent for antibiotic-associated diarrhea.

Astaxanthin nanoparticles ameliorate dextran sulfate sodium-induced colitis by alleviating oxidative stress, regulating intestinal flora, and protecting the intestinal barrier

This study aimed to develop a novel astaxanthin nanoparticle using gum arabic (GA) and whey protein powder enriched with milk fat globule membranes (MFGM-WPI) as carriers and to investigate its effect and alleviation mechanism on colitis in mice. We demonstrated that MFGM-GA-astaxanthin could improve the bioaccessibility of astaxanthin and cope with oxidative stress more effectively in a Caco-2 cell model. In vivo studies demonstrated that MFGM-GA-astaxanthin alleviated colitis symptoms and repaired intestinal barrier function by increasing the expression of mucin 2, occludin, and zonula occludens-1. This was attributed to the alleviating effect of MFGM-GA-astaxanthin on oxidative stress. Moreover, MFGM-GA-astaxanthin restored the abnormalities of flora caused by dextran sulfate sodium, including Lactobacillus, Bacteroides, Ruminococcus, and Shigella. This study provides a basis for the therapeutic effect of astaxanthin nanoparticles on colon diseases.

Tangeretin attenuates bleomycin-induced pulmonary fibrosis by inhibiting epithelial-mesenchymal transition via the PI3K/Akt pathway

Background: Pulmonary fibrosis (PF) is a terminal pathological change in a variety of lung diseases characterized by excessive deposition of extracellular matrix, for which effective treatment is lacking. Tangeretin (Tan), a flavonoid derived from citrus, has been shown to have a wide range of pharmacological effects. This study aimed to investigate the role and potential mechanisms of Tan on pulmonary fibrosis. Methods: A model of pulmonary fibrosis was established by administering bleomycin through tracheal drip, followed by administering Tan or pirfenidone through gavage. HE and Masson staining were employed to assess the extent of pulmonary fibrosis. Subsequently, Western blot, enzyme-linked immunosorbent assay (ELISA), RNA sequencing, and immunohistochemistry techniques were employed to uncover the protective mechanism of Tan in PF mice. Furthermore, A549 cells were stimulated with TGF-β1 to induce epithelial-mesenchymal transition (EMT) and demonstrate the effectiveness of Tan in mitigating PF. Results: Tan significantly ameliorated bleomycin-induced pulmonary fibrosis, improved fibrotic pathological changes, and collagen deposition in the lungs, and reduced lung inflammation and oxidative stress. The KEGG pathway enrichment analysis revealed a higher number of enriched genes in the PI3K/Akt pathway. Additionally, Tan can inhibit the EMT process related to pulmonary fibrosis. Conclusion: Taken together, the above research results indicate that Tan suppresses inflammation, oxidative stress, and EMT in BLM-induced pulmonary fibrosis via the PI3K/Akt pathway and is a potential agent for the treatment of pulmonary fibrosis.

The alleviating effect of ellagic acid on DSS-induced colitis via regulating gut microbiomes and gene expression of colonic epithelial cells

The anti-inflammatory effect of ellagic acid (EA) and its possible underlying mechanism in dextran sulfate sodium (DSS)-induced mouse chronic colonic inflammation were studied. It was observed that EA administration significantly alleviated the colonic inflammation phenotypes, including decreasing the disease activity index (DAI), enhancing the body weight loss, and improving the shortened length of the colon and pathological damage of colon tissue. Additionally, EA reshaped the constitution of the gut microbiota by elevating the ratio of Bacteroidetes along with Bacteroides and Muribaculaceae, while decreasing the proportion of Firmicutes. The Phylogenetic Investigation of Communities by Reconstruction of Unobserved States 2 (PICRUSt2) revealed that the metabolic function of the gut microbiota was also changed. Furthermore, mouse colon transcriptome analysis showed that the tight junction and peroxisome proliferator-activated receptor (PPAR) signaling pathways were activated and the expressions of related genes were upregulated after EA intervention. These results showed that EA could remodel the gut bacterial composition, change the intestinal epithelial cell gene expressions in mice, and consequently improve the colonic inflammatory symptoms.

Anti-Inflammatory and Gut Microbiota Modulation Potentials of Flavonoids Extracted from Passiflora foetida Fruits

This study aimed to explore the anti-inflammatory and gut microbiota modulation potentials of flavonoid-rich fraction (PFF) extracted from Passiflora foetida fruits. The results showed that PFF markedly reduced the production of nitric oxide (NO), tumor necrosis factor α (TNF-α), and interleukin 6 (IL-6) in LPS-stimulated RAW 264.7 cells. Meanwhile, PFF treatment also effectively decreased the phosphorylation levels of MAPK, PI3K/Akt, and NF-κB signaling-pathway-related proteins (ERK, JNK, p38, Akt, and p65). Moreover, PFF had an impact on microbial composition and metabolites in a four-stage dynamic simulator of human gut microbiota (BFBL gut model). Specifically, PFF exhibited the growth-promoting ability of several beneficial bacteria, including Bifidobacterium, Enterococcus, Lactobacillus, and Roseburia, and short-chain fatty acid (SCFA) generation ability in gut microbiota. In addition, spectroscopic data revealed that PFF mainly contained five flavonoid compounds, which may be bioactive compounds with anti-inflammatory and gut microbiota modulation potentials. Therefore, PFF could be utilized as a natural anti-inflammatory agent or supplement to health products.

Four novel sleep-promoting peptides screened and identified from bovine casein hydrolysates using a patch-clamp model in vitro and Caenorhabditis elegans in vivo

Bovine casein hydrolysates (CHs) have demonstrated sleep-promoting activities. However, only few peptides were identified from CHs with sleep-promoting effects. In this work, an in vitro model based on the electrophysiology of brain neurons was established for the evaluation of sleep-promoting effects. Based on this model, four novel peptides were systematically separated from CH. Compared with the control group, the action potential (AP) inhibitory rate of four peptides increased by 38.63%, 340.93%, 233.28%, and 900%, respectively, and the membrane potential (MP) change rate of four peptides increased by 319.78%, 503.09%, 381.22%, and 547.10%, respectively. These results suggested that four peptides have sleep-promoting activities. Furthermore, Caenorhabditis elegans (C. elegans) sleep behavior results indicated that all the four peptides could significantly increase the total sleep duration, the motionless sleep duration of C. elegans, implying that these four peptides can significantly improve sleep. The LC-MS/MS results showed that the primary structures of these novel peptides were HQGLPQEVLNENLLR (α_s1-CN, f8-22), YKVPQLEIVPNSAEER (α_s1-CN, f104-119), HPIKHQGLPQEVLNENLLR (α_s1-CN, f4-22), and VPQLEIVPNSAEER (α_s1-CN, f106-119). Overall, this study revealed that the four novel sleep-promoting peptides identified were strong candidates as potential functional ingredients in the development of sleep-promoting products.

Review of recent advances on health benefits, microbial transformations, and authenticity identification of Citri reticulatae Pericarpium bioactive compounds

The extensive health-promoting effects of Citri Reticulatae Pericarpium (CRP) have attracted researchers' interest. The difference in storage time, varieties and origin of CRP are closely related to the content of bioactive compounds they contain. The consitituent transformation mediated by environmental microorganisms (bacteria and fungi) and the production of new bioactive components during the storage process may be the main reason for 'the older, the better' of CRP. In addition, the gap in price between different varieties can be as large as 8 times, while the difference due to age can even reach 20 times, making the 'marketing young-CRP as old-CRP and counterfeiting origin' flood the entire market, seriously harming consumers' interests. However, so far, the research on CRP is relatively decentralized. In particular, a summary of the microbial transformation and authenticity identification of CRP has not been reported. Therefore, this review systematically summarized the recent advances on the main bioactive compounds, the major biological activities, the microbial transformation process, the structure, and content changes of the active substances during the transformation process, and authenticity identification of CRP. Furthermore, challenges and perspectives concerning the future research on CRP were proposed.

Total flavonoids of Tetrastigma hemsleyanum Diels et Gilg inhibits colorectal tumor growth by modulating gut microbiota and metabolites

Tetrastigma hemsleyanum Diels et Gilg is a dietary supplement in southern China. The total flavonoids of T. hemsleyanum (THTF) can be used for gastrointestinal disease treatment. Colorectal cancer (CRC) is associated with gut microbiota dysbiosis. This study was designed to investigate the effect of THTF on CRC from gut microbiota and fecal metabolomics. THTF (120 mg/kg) oral gavage reduced tumor growth and protected intestinal function (p-p65/p65, ZO-1) in HCT116 xenografts. THTF increased probiotics Bifidobacteriales, Bifidobacteriaceae, Bifidobacterium, Bifidobacterium pseudolongum, and decreased "harmful" bacteria Bacteroidota, Firmicutes, Bacteroidia, Rikenellaceae, Odoribacter, Alistipes richness. Furthermore, THTF restored abnormal fecal metabolite levels. It showed a strong correlation among gut microbiota, metabolites, and tumor weight. Finally, THTF promoted Bifidobacterium pseudolongum growth in vitro, whose cell-free supernatant further inhibited HCT116 cell proliferation and clonogenicity. Together, THTF delays CRC tumor growth by maintaining microbiota homeostasis, restoring fecal metabolites, and protecting intestinal function.

Natural flavones from edible and medicinal plants exhibit enormous potential to treat ulcerative colitis

Ulcerative colitis (UC) is a chronic aspecific gut inflammatory disorder that primarily involves the recta and colons. It mostly presents as a long course of repeated attacks. This disease, characterized by intermittent diarrhoea, fecal blood, stomachache, and tenesmus, severely decreases the living quality of sick persons. UC is difficult to heal, has a high recurrence rate, and is tightly related to the incidence of colon cancer. Although there are a number of drugs available for the suppression of colitis, the conventional therapy possesses certain limitations and severe adverse reactions. Thus, it is extremely required for safe and effective medicines for colitis, and naturally derived flavones exhibited huge prospects. This study focused on the advancement of naturally derived flavones from edible and pharmaceutical plants for treating colitis. The underlying mechanisms of natural-derived flavones in treating UC were closely linked to the regulation of enteric barrier function, immune-inflammatory responses, oxidative stress, gut microflora, and SCFAs production. The prominent effects and safety of natural-derived flavones make them promising candidate drugs for colitis treatment.

New Insights of Biological Functions of Natural Polyphenols in Inflammatory Intestinal Diseases

The intestine is critically crucial for nutrient absorption and host defense against exogenous stimuli. Inflammation-related intestinal diseases, including enteritis, inflammatory bowel disease (IBD), and colorectal cancer (CRC), are heavy burdens for human beings due to their high incidence and devastating clinical symptoms. Current studies have confirmed that inflammatory responses, along with oxidative stress and dysbiosis as critical pathogenesis, are involved in most intestinal diseases. Polyphenols are secondary metabolites derived from plants, which possess convincible anti-oxidative and anti-inflammatory properties, as well as regulation of intestinal microbiome, indicating the potential applications in enterocolitis and CRC. Actually, accumulating studies based on the biological functions of polyphenols have been performed to investigate the functional roles and underlying mechanisms over the last few decades. Based on the mounting evidence of literature, the objective of this review is to outline the current research progress regarding the category, biological functions, and metabolism of polyphenols within the intestine, as well as applications for the prevention and treatment of intestinal diseases, which might provide ever-expanding new insights for the utilization of natural polyphenols.

Dietary (poly)phenols mitigate inflammatory bowel disease: Therapeutic targets, mechanisms of action, and clinical observations

Inflammatory bowel diseases (IBD), which include Crohn's disease and ulcerative colitis, are a rapidly growing public health concern worldwide. These diseases are heterogeneous at the clinical, immunological, molecular, genetic, and microbial level, but characteristically involve a disrupted immune-microbiome axis. Shortcomings in conventional treatment options warrant the need for novel therapeutic strategies to mitigate these life-long and relapsing disorders of the gastrointestinal tract. Polyphenols, a diverse group of phytochemicals, have gained attention as candidate treatments due to their array of biological effects. Polyphenols exert broad anti-inflammatory and antioxidant effects through the modulation of cellular signaling pathways and transcription factors important in IBD progression. Polyphenols also bidirectionally modulate the gut microbiome, supporting commensals and inhibiting pathogens. One of the primary means by which gut microbiota interface with the host is through the production of metabolites, which are small molecules produced as intermediate or end products of metabolism. There is growing evidence to support that modulation of the gut microbiome by polyphenols restores microbially derived metabolites critical to the maintenance of intestinal homeostasis that are adversely disrupted in IBD. This review aims to define the therapeutic targets of polyphenols that may be important for mitigation of IBD symptoms, as well as to collate evidence for their clinical use from randomized clinical trials.

Integrated Microbiome and Metabolomic Analysis Reveal the Repair Mechanisms of Ovalbumin on the Intestine Barrier of Colitis Mice

The development and progression of colitis would detrimentally destroy the intestine barrier. However, there remains a paucity of evidence on whether ovalbumin (OVA) can be used as a nutritional food protein to repair the intestinal barrier. In this study, the repairing mechanism of OVA on intestinal barrier was thoroughly investigated by gut microbiota and untargeted metabolomics techniques. The findings demonstrated that OVA reduced intestinal permeability and restored mucin (0.75 ± 0.06) and tight junction (TJ) protein (0.67 ± 0.14) expression in colitis mice caused by 3% dextran sulfate sodium (DSS). In addition, the inflammation response and oxidative stress were also attenuated. The intake of OVA upregulated the abundance of Lactobacillaceae (7.60 ± 3.34%) and Akkermansiaceae (10.39 ± 5.97%). Furthermore, OVA upregulated the abundance of inosine (6.06 ± 0.36%), putrescine (4.14 ± 0.20%), and glycocholic acid (5.59 ± 0.23%) in colitis mice through ATP binding cassette (ABC) transporters and bile secretion pathways. In summary, our findings revealed that OVA could maintain intestinal health, which may provide crucial insights for preventing and treating intestinal diseases.

Dietary 5-demethylnobiletin prevents antibiotic-associated dysbiosis of gut microbiota and damage to the colonic barrier

5-Demethylnobiletin (5DN) is an important ingredient of citrus extract that is rich in polymethoxyflavones (PMFs). In this study, we systemically investigated the preventive effects of 5DN on antibiotic-associated intestinal disturbances. Experimental mice were gavaged 0.2 mL per day of the antibiotic cocktail (12.5 g L^-1 cefuroxime and 10 g L^-1 levofloxacin) for 10 days, accompanied by dietary 0.05% 5DN for 10 and 20 days. The results showed that the combination of cefuroxime and levofloxacin caused swelling of the cecum and injury to the colon tissue. Meanwhile, the balance of intestinal oxidative stress and the barrier function of mice was also damaged by the antibiotics through upregulation of the relative mRNA levels of superoxide dismutase 3 (SOD3), quinine oxidoreductase 1 (NQO1) and glutathione peroxidase 1 (GPX1), and downregulation of the relative protein levels of tight junction proteins (TJs). Moreover, antibiotic exposure led to disorder of the gut microbiota, particularly increased harmful bacteria (Proteobacteria) and decreased beneficial bacteria (Bacteroideta). However, dietary 5DN could reduce antibiotic-associated intestinal damage, evidenced by the results that 5DN alleviated gut oxidative damage and attenuated intestinal barrier injury via increasing the expression of TJs including occludin and zonula occluden1 (ZO1). Additionally, dietary 5DN modulated the composition of the gut microbiota in antibiotic-treated mice by increasing the relative levels of beneficial bacteria, such as Dubosiella and Lactobacillus. Moreover, PMFs increased the contents of isobutyric acid and butyric acid, which were almost eliminated by antibiotic exposure. In conclusion, 5DN could alleviate antibiotic-related imbalance of intestinal oxidative stress, barrier function damage, intestinal flora disorders and the reduction of short-chain fatty acids (SCFAs), which lays a foundation for exploring safer and more effective ways to prevent or mitigate antibiotic-associated intestinal damage.

Rosmarinic Acid Restores Colonic Mucus Secretion in Colitis Mice by Regulating Gut Microbiota-Derived Metabolites and the Activation of Inflammasomes

Maintaining a steady state of mucus barrier is an important potential target for polyphenol to exert its anticolitis activity. This study elucidates the pivotal role of polyphenol rosmaric acid (RA) in regulating the mucus barrier function and alleviating inflammation by identifying its gut microbiota-derived metabolites and evaluating its inhibitory effect on inflammasomes in colitis mice. Results demonstrated that RA treatment promoted the proliferation of goblet cells and restored the level of mucus secretion, especially Muc2. RA reshaped the microbiota of colitis mice, particularly the boost of core probiotics, such as p. Bacteroidaceae, f. Muribaculaceae, g. Muribaculaceae, g. Alistipes, and g. Clostridia_UCG-014. Nontargeted metabonomics and targeted metabonomics confirmed a significant increase in the bile acids and their metabolites (7-sulfocholic acid, stercobilin, chenodeoxycholic acid 3-sulfate, chenodeoxycholic acid sulfate, and ursodeoxycholic acid 3-sulfate), indole metabolites ((R)-2,3-dihydro-3,5-dihydroxy-2-oxo-3-indoleacetic acid, frovatriptan, 3-formyl-6-hydroxyindole, and brassicanal A), and short-chain fatty acids (SCFAs) (acetic acid, butyric acid, isobutyric acid, isovaleric acid, and valeric acid) that contributed to the strengthened mucus barrier function. In addition, being absorbed mainly in the lower digestive tract, RA inhibited the overexpression of inflammasomes (especially NLRP6) that occurred in colitis mice to promote the mucus secretion of goblet cells. These data confirmed that RA, as a promising candidate to enhance gut health, restored colonic mucus secretion in colitis mice by mediating the production of gut microbiota-derived metabolites and the overexpression of inflammasomes. The presented study provides scientific evidence explaining the apparent paradox of low bioavailability and high bioactivity in polyphenols.

Evolving interplay between natural products and gut microbiota

Growing evidence suggests gut microbiota status affects human health, and microbiota imbalance will induce multiple disorders. Natural products are gaining increasing attention for their therapeutical effects and less side effects. The emerging studies support that the activities of many natural products are dependent on gut microbiota, meanwhile gut microbiota is modulated by natural products. In this review, we summarized the interplay between the gut microbiota and host disease, and the emerging molecular mechanisms of the interaction between natural products and gut microbiota. Focusing on gut microbiota metabolite of various natural products, and the effects of natural products on gut microbiota, we summarized the biotransformation pathways of natural products, and discussed the effect of natural products on the composition modulation of gut microbiota, protection of gut mucosal barrier and modulation of the gut microbiota metabolites. Dissecting the interplay between gut microbiota and natural products will help elucidate the therapeutic mechanisms of natural products.

Galactooligosaccharides ameliorate dietary advanced glycation end product-induced intestinal barrier damage in C57BL/6 mice by modulation of the intestinal microbiome

Advanced glycation end products (AGEs) are increasingly recognized as potentially pathogenic components of processed foods, and long-term consumption of dietary AGEs triggers disruption of the intestinal barrier integrity and increases the risk of chronic diseases. Galactooligosaccharides (GOS) as prebiotics can modulate the intestinal microbiota and improve the intestinal barrier integrity. In this study, we aimed to investigate whether GOS could ameliorate the intestinal barrier damage induced by AGEs. The results showed an increased number of goblet cells (AGEs vs. H-GOS, 133.4 vs. 174.7, p < 0.05) and neutral mucin area (PAS positive area, 7.29% vs. 10.05%, p < 0.05). Upregulated expressions of occludin and claudin-1 and improved intestinal barrier integrity were observed in the H-GOS group. Using 16S rRNA sequencing analysis, we found that GOS significantly reduced the high enrichment of Akkermansia (16.95% vs. 1.29%, p < 0.05) induced by dietary AGEs while increasing the content of short-chain fatty acids. Fecal microbiota transplantation (FMT) showed that AGE-induced damage to the intestinal mucus barrier was reversed in the H-GOS transplanted group. Collectively, GOS ameliorated dietary AGE-induced intestinal barrier damage by reversing the dysregulated state of the intestinal microbiota. Our study lays the foundation for further research on dietary guidelines for populations with high AGE diets.

The Chemistry and the Anti-Inflammatory Activity of Polymethoxyflavonoids from Citrus Genus

Polymethoxyflavonoids (PMFs) are a large group of compounds belonging to the more general class of flavonoids that possess a flavan carbon framework decorated with a variable number of methoxy groups. Hydroxylated polymethoxyflavonoids (HPMFs), instead, are characterized by the presence of both hydroxyl and methoxy groups in their structural unities. Some of these compounds are the aglycone part in a glycoside structure in which the glycosidic linkage can involve the -OH at various positions. These compounds are particular to Citrus genus plants, especially in fruits, and they are present mainly in the peel. A considerable number of PMFs and HPMFs have shown promising biological activities and they are considered to be important nutraceuticals, responsible for some of the known beneficial effects on health associated with a regular consumption of Citrus fruits. Among their several actions on human health, it is notable that the relevant contribution in controlling the intracellular redox imbalance is associated with the inflammation processes. In this work, we aim to describe the status concerning the chemical identification and the anti-inflammatory activity of both PMFs and HPMFs. In particular, all of the chemical entities unambiguously identified by isolation and complete NMR analysis, and for which a biochemical evaluation on the pure compound was performed, are included in this paper.

Acetylation Enhances the Anticancer Activity and Oral Bioavailability of 5-Demethyltangeretin

A kind of hydroxylated polymethoxyflavone (PMFs) existing in the citrus genus, 5-Demethyltangeretin (5-DTAN), has been reported to possess several bioactivities in vitro and in vivo. The aim of this study was to investigate whether acetylation could enhance the anticancer activity and oral bioavailability of 5-DTAN. PC-3 human prostate cancer cells were treated with tangeretin (TAN), 5-DTAN, and 5-acetylated TAN (5-ATAN), and the results showed that the cytotoxic effect 5-ATAN (IC50 value of 5.1 µM) on the cell viability of PC-3 cells was stronger than that of TAN (IC50 value of 17.2 µM) and 5-DTAN (IC50 value of 11.8 µM). Compared to 5-DTAN, 5-ATAN treatment caused a more pronounced DNA ladder, increased the sub-G1 phase population, and induced G2/M phase arrest in the cell cycle of PC-3 cells. We also found that 5-ATAN triggered the activation of caspase-3 and the progression of the intrinsic mitochondrial pathway in PC-3 cells, suggesting the induction of apoptosis. In a cell wound healing test, 5-ATAN dose-dependently reduced the cell migration, and the expression of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) was decreased after 48 h of 5-ATAN treatment. Moreover, oral administration of 5-ATAN showed a significantly stronger inhibitory effect on tumor size and tumor weight in tumor-bearing nude mice than those of vehicle or the 5-DTAN group (p < 0.05). Furthermore, pharmacokinetic results showed that single-dose oral administration of 5-ATAN exhibited a higher maximum concentration (Cmax) and area under the curve (AUC) of 5-DTAN in plasma than that of 5-DTAN. More extensive distribution of 5-DTAN to most tissues of mice was also observed in mice treated with 5-ATAN for 7 days. In conclusion, acetylation strongly enhances the anticancer activity and oral bioavailability of 5-DTAN and could be a promising strategy to promote the potential bioactivities of natural products.

Mechanism of Citri Reticulatae Pericarpium as an Anticancer Agent from the Perspective of Flavonoids: A Review

Citri Reticulatae Pericarpium (CRP), also known as “chenpi”, is the most common qi-regulating drug in traditional Chinese medicine. It is often used to treat cough and indigestion, but in recent years, it has been found to have multi-faceted anti-cancer effects. This article reviews the pharmacology of CRP and the mechanism of the action of flavonoids, the key components of CRP, against cancers including breast cancer, lung cancer, prostate cancer, hepatic carcinoma, gastric cancer, colorectal cancer, esophageal cancer, cervical cancer, bladder cancer and other cancers with a high diagnosis rate. Finally, the specific roles of CRP in important phenotypes such as cell proliferation, apoptosis, autophagy and migration–invasion in cancer were analyzed, and the possible prospects and deficiencies of CRP as an anticancer agent were evaluated.

Potential effects of fructus aurantii ethanol extracts against colitis-associated carcinogenesis through coordination of Notch/NF-κB/IL-1 signaling pathways

Colitis-associated cancer (CAC) is the colorectal cancer (CRC) subtype that is difficult to treat, and shows high mortality. The consumption of flavonoid-rich fructus aurantii extracts (FAE) has been associated with multiple beneficial effects including anti-inflammatory and anti-cancer properties, but the potential effects on the colitis-associated carcinogenesis have not been thoroughly investigated. Recent clinical data show that, as yet, few agents clearly inhibited CRC development in long-standing inflammatory bowel diseases. Here, we identified that FAE showed significant efficiency to inhibit HT-29 cell proliferation. The potential of FAE in vivo was further evaluated in an AOM/DSS-induced CAC mouse model. Intriguingly, FAE diminished the number of polyps in mice. Furthermore, FAE inhibited CAC by regulating the gene expression of Notch/ NF-κB/IL-1 signaling pathways. Collectively, these results were indicative of FAE has great potential in CAC prevention and treatment.

Bacillus amyloliquefaciens Enriched Camel Milk Attenuated Colitis Symptoms in Mice Model

Fermented camel's milk has various health beneficial prebiotics and probiotics. This study aimed to evaluate the preventive efficacy of Bacillus amyloliquefaciens enriched camel milk (BEY) in 2-, 4- and 6-Trinitrobenzenesulfonic acid (TNBS)-induced colitis mice models. To this end, the immune modulatory effects of Bacillus amyloliquefaciens (BA) on TNF-α challenged HT29 colon cells were estimated using the cell proliferation and cytokines ELISA method. BEY was prepared using the incubation method and nutritional value was quantified by comparing it to commercial yogurt. Furthermore, TNBS-induced colitis was established and the level of disease index, pathological scores, and inflammatory markers of BEY-treated mice using macroscopic and microscopic examinations, qPCR and immunoblot were investigated. The results demonstrate that BA is non-toxic to HT29 colon cells and balanced the inflammatory cytokines. BEY reduced the colitis disease index, and improved the body weight and colon length of the TNBS-induced mice. Additionally, Myeloperoxidase (MPO) and pro-inflammatory cytokines (IL1β, IL6, IL8 and TNF-α) were attenuated by BEY treatment. Moreover, the inflammatory progress mRNA and protein markers nuclear factor kappa B (NFκB), phosphatase and tensin homolog (PTEN), proliferating cell nuclear antigen (PCNA), cyclooxygenase-2 (COX-2) and occludin were significantly down-regulated by BEY treatment. Interestingly, significant suppression of PCNA was observed in colonic tissues using the immunohistochemical examination. Treatment with BEY increased the epigenetic (microRNA217) interactions with PCNA. In conclusion, the BEY clearly alleviated the colitis symptoms and in the future could be used to formulate a probiotic-based diet for the host gut health and control the inflammatory bowel syndrome in mammals.

Camel milk modulates the gut microbiota and has anti-inflammatory effects in a mouse model of colitis

Camel milk is a nutritionally rich food that shows anti-inflammatory, immune regulation, and gut microbiota maintenance properties. However, the relationship between camel milk and the intestinal microbiota during colitis is unclear. Herein, we evaluated the protective effect of camel milk in mice with colitis induced using dextran sodium sulfate. Our results showed that camel milk can prevent body weight loss and colon shortening, reduce the disease activity index, and attenuate colon tissue damage. Additionally, camel milk could reduce the overexpression of inflammatory factors, inhibit the apoptosis of intestinal epithelial cells, and promote the expression of claudin-1, occludin, and zonula occludens-1 proteins. Moreover, camel milk effectively regulated intestinal microbiota in mice with colitis by increasing the gut microbiota diversity, increasing the abundance of beneficial bacteria (such as g_norank_f_Muribaculaceae, and Lachnospiraceae_NK4A136_group), and reducing the number of harmful bacteria (Bacteroides, Escherichia-Shigella). In addition, camel milk increased the levels of intestinal short-chain fatty acids. The results of the present study demonstrated that via regulating the intestinal microbiota, maintaining intestinal barrier function, and inhibiting proinflammatory cytokines, camel milk can ameliorate dextran sodium sulfate-induced colitis.

Simotang Alleviates the Gastrointestinal Side Effects of Chemotherapy by Altering Gut Microbiota

Simotang oral liquid (SMT) is a traditional Chinese medicine (TCM) consisting of four natural plants and is used to alleviate gastrointestinal side effects after chemotherapy and functional dyspepsia (FD). However, the mechanism by which SMT helps cure these gastrointestinal diseases is still unknown. Here, we discovered that SMT could alleviate gastrointestinal side effects after chemotherapy by altering gut microbiota. C57BL/6J mice were treated with cisplatin (DDP) and SMT, and biological samples were collected. Pathological changes in the small intestine were observed, and the intestinal injury score was assessed. The expression levels of the inflammatory factors IL-1β and IL-6 and the adhesive factors Occludin and ZO-1 in mouse blood or small intestine tissue were also detected. Moreover, the gut microbiota was analyzed by high-throughput sequencing of 16S rRNA amplicons. SMT was found to effectively reduce gastrointestinal mucositis after DDP injection, which lowered inflammation and tightened the intestinal epithelial cells. Gut microbiota analysis showed that the abundance of the anti-inflammatory microbiota was downregulated and that the inflammatory microbiota was upregulated in DDP-treated mice. SMT upregulated anti-inflammatory and anticancer microbiota abundance, while the inflammatory microbiota was downregulated. An antibiotic cocktail (ABX) was also used to delete mice gut microbiota to test the importance of gut microbiota, and we found that SMT could not alleviate gastrointestinal mucositis after DDP injection, showing that gut microbiota might be an important mediator of SMT treatment. Our study provides evidence that SMT might moderate gastrointestinal mucositis after chemotherapy by altering gut microbiota.

Hydroxytyrosol Alleviates Dextran Sulfate Sodium-Induced Colitis by Modulating Inflammatory Responses, Intestinal Barrier, and Microbiome

Hydroxytyrosol (HT), a polyphenol derived from olive oil, was examined against dextran sulfate sodium (DSS)-induced colitis to study its potential in preventing colitis and the underlying mechanisms involved. The low dose and high dose of HT used in mice were 10 and 50 mg/kg, respectively. Research findings have shown that HT is effective in preventing colitis by alleviating the signs of colitis. HT intervention significantly reduces colitis markers such as myeloperoxidase (MPO) and proinflammatory cytokine (IL-6, IL-1β, and TNF-α). Also, mice treated with a high dose of HT showed increased secretion of antioxidant enzymes (heme oxygenase-1 (HO) and anti-inflammatory cytokine (IL-10) by 2.32- and 2.28-fold, respectively, in comparison to the DSS-treated group. Modulation effects of HT on the antioxidant signal pathway (NRF2) and the inflammatory pathway (NF-κB) were confirmed. Meanwhile, HT promoted the regeneration of the intestinal barrier and maintained intestinal functional homeostasis by boosting the regeneration of goblet cells and the expression of mucin protein (Muc2) and tight junction (TJ) proteins (claudin-1, occludin, and Zonula Occludens-1). Moreover, HT intervention obviously transformed the gut microbiota, leading to a lower abundance of inflammation-related microbes (e.g., Bacteroidaceae and Desulfovibrionaceae) and a higher level of short-chain fatty acids (SCFAs) producing bacteria (e.g., Lachnospiraceae, Muribaculaceae, ASF356, and Colidextribacter). Scientific evidence for the beneficial effect of the "Mediterranean diet" (MD) on intestinal health was achieved by elucidating the alleviation mechanism of hydroxytyrosol on colitis.