The role of immunomodulators on intestinal barrier homeostasis in experimental models

Heat stroke-induced cerebral cortex nerve injury by mitochondrial dysfunction: A comprehensive multi-omics profiling analysis

In recent years, global warming has led to frequent instances of extremely high temperatures during summer, arousing significant concern about the adverse effects of high temperature. Among these, heat stroke is the most serious, which has detrimental effects on the all organs of human body, especially on brain. However, the comprehensive pathogenesis leading to brain damage remains unclear. In this study, we constructed a mouse model of heat stroke and conducted multi-omics profiling to identify relevant pathogenesis induced by heat stroke. The mice were placed in a constant temperature chamber at 42 °C with a humidity of 50 %, and the criteria for success in modeling were that the rectal temperature reached 42 °C and that the mice were trembling. Then the mice were immediately taken out for further experiments. Firstly, we conducted cFos protein localization and identified the cerebral cortex, especially the anterior cingulate cortex as the region exhibiting the most pronounced damage. Secondly, we performed metabolomics, transcriptomics, and proteomics analysis on cerebral cortex. This multi-omics investigation unveiled noteworthy alterations in proteins and metabolites within pathways associated with neurotransmitter systems, heatstroke-induced mitochondrial dysfunction, encompassing histidine and pentose phosphate metabolic pathways, as well as oxidative stress. In addition, the cerebral cortex exhibited pronounced Reactive Oxygen Species (ROS) production, alongside significant downregulation of the mitochondrial outer membrane protein Tomm40 and mitochondrial permeability transition pore, implicating cerebral cortex mitochondrial dysfunction as the primary instigator of neural impairment. This study marks a significant milestone as the first to employ multi-omics analysis in exploring the molecular mechanisms underlying heat stroke-induced damage in cerebral cortex neurons. It comprehensively identifies all potentially impacted pathways by heat stroke, laying a solid foundation for ensuing research endeavors. Consequently, this study introduces a fresh angle to clinical approaches in heatstroke prevention and treatment, as well as establishes an innovative groundwork for shaping future-forward environmental policies.

Up-regulation of sortase-dependent pili in Bifidobacterium longum BBMN68 in response to bile stress enhances its adhesion to HT-29 cells

Adhesion to gastrointestinal tract is crucial for bifidobacteria to exert their probiotic effects. Our previous work found that bile salts significantly enhance the adhesion ability of Bifidobacterium longum BBMN68 to HT-29 cells. In this study, trypsin-shaving and LC-MS/MS-based surface proteomics were employed to identify surface proteins involved in bile stress response. Among the 829 differentially expressed proteins, 56 up-regulated proteins with a fold change >1.5 were subjected to further analysis. Notably, the minor pilin subunit FimB was 4.98-fold up-regulated in response to bile stress. In silico analysis and RT-PCR confirmed that gene fimB, fimA and srtC were co-transcribed and contributed to the biosynthesis of sortase-dependent pili Pil1. Moreover, scanning electron microscopy and immunogold electron microscopy assays showed increased abundance and length of Pil1 on BBMN68 under bile stress. As the major pilin subunit FimA serves as adhesion component of Pil1, an inhibition assay using anti-FimA antibodies further confirmed the critical role of Pil1 in mediating the adhesion of BBMN68 to HT-29 cells under bile stress. Our findings suggest that the up-regulation of Pil1 in response to bile stress enhances the adhesion of BBMN68 to intestinal epithelial cells, highlighting a novel mechanism of gut persistence in B. longum strains.

Effects of crude protein and non-essential amino acids on growth performance, blood profile, and intestinal health of weaned piglets

This study investigated the effect of crude protein (CP) and non-essential amino acid (NEAA) supplementation on the growth performance, blood profile, intestinal morphology, mRNA relative abundance of inflammatory and antioxidant markers, and tight junction proteins in piglets over the first 2 weeks after weaning. Ninety 21-day-old piglets (7.55 ± 0.72 kg) were assigned in a randomized block design to one of three dietary treatments: (1) high CP, a diet with 24% CP; (2) low CP, a diet with 18% CP; and (3) low CP + NEAA, a diet with 18% CP supplemented with 5 g/kg Arg (L-arginine; purity >99%) and 10 g/kg Glu + Gln (minimum 10% L-glutamine and minimum 10% L-glutamate). Piglets were fed with corn-soybean meal basal diets in a 14-day trial. There was an improvement (p < 0.05) in the feed conversion ratio of piglets fed the high-CP diet compared to treatments with low CP or low CP + NEAA. Serum urea nitrogen was higher (p < 0.05) in piglets fed high CP compared to other dietary treatments. In the duodenum, the villus height of animals fed the low-CP + NEAA diets was greater (p < 0.05) than those fed with the high- and low-CP diets. The goblet cell proportion of piglets fed low CP + NEAA or high CP was higher (p < 0.05) compared to low CP. In the jejunum, the crypt depth of the piglets with the high-CP dietary treatment was greater (p < 0.05) in comparison with low CP + NEAA. In the jejunum, IFN-γ mRNA expression was higher (p < 0.05) in animals fed the high-CP diets compared to other dietary treatments. However, superoxide dismutase and occludin mRNA expression were higher (p < 0.05) in animals fed low CP + NEAA than in piglets on the high-CP diets. In the ileum, the number of Peyer's patches in piglets fed high CP was higher (p < 0.05) compared to other dietary treatments. In conclusion, the high-CP diet (24% CP) improves the feed conversion of piglets in the first 2 weeks after weaning compared to the low-CP diet (18% CP) supplemented or not with NEAA. However, the low-CP diet supplemented with NEAA (Arg, Gln, and Glu) improves intestinal health in piglets by promoting greater villus height and proportion of goblet cells in the duodenum, reducing jejunal crypt depth, and reducing Peyer's number patches in the ileum. In addition, piglets that received the low-CP + NEAA diet showed an increase in superoxide dismutase and occludin and a lower expression of IFN-γ mRNA.

Prolonged administration of total glucosides of paeony improves intestinal immune imbalance and epithelial barrier damage in collagen-induced arthritis rats based on metabolomics-network pharmacology integrated analysis

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease characterized by synovial inflammation and joint damage with complex pathological mechanisms. In recent years, many studies have shown that the dysregulation of intestinal mucosal immunity and the damage of the epithelial barrier are closely related to the occurrence of RA. Total glucosides of paeony (TGP) have been used clinically for the treatment of RA in China for decades, while the pharmacological mechanism is still uncertain. The purpose of this study was to investigate the regulatory effect and mechanism of TGP on intestinal immunity and epithelial barrier in RA model rats. The results showed that TGP alleviated immune hyperfunction by regulating the ratio of CD3+, CD4+ and CD8+ in different lymphocyte synthesis sites of the small intestine, including Peyer's patches (PPs), intraepithelial lymphocytes (IELs), and lamina propria lymphocytes (LPLs). Specially, TGP first exhibited immunomodulatory effects on sites close to the intestinal lumen (IELs and LPLs), and then on PPs far away from the intestinal lumen as the administration time prolonged. Meanwhile, TGP restores the intestinal epithelial barrier by upregulating the ratio of villi height (V)/crypt depth (C) and expression of tight junction proteins (ZO-1, occludin). Finally, the integrated analysis of metabolomics-network pharmacology was also used to explore the possible regulation mechanism of TGP on the intestinal tract. Metabolomics analysis revealed that TGP reversed the intestinal metabolic profile disturbance in CIA rats, and identified 32 biomarkers and 163 corresponding targets; network pharmacology analysis identified 111 potential targets for TGP to treat RA. By intersecting the results of the two, three key targets such as ADA, PNP and TYR were determined. Pharmacological verification experiments showed that the levels of ADA and PNP in the small intestine of CIA rats were significantly increased, while TGP significantly decreased their ADA and PNP levels. In conclusion, purine metabolism may play an important role in the process of TGP improving RA-induced intestinal immune imbalance and impaired epithelial barrier.

The What and Who of Dietary Lignans in Human Health: Special Attention to Estrogen Effects and Safety Evaluation

Lignans are a group of phenolic compounds found in plant-based diets. The human body can obtain lignans through diet, which are then metabolized into enterolignans. The enterolignans have been linked to several health benefits, including anticancer, anti-inflammatory, antioxidant effects, and estrogen effects. This review explores the relationship between the estrogenic effects of lignans and health. This review not only considers the estrogen-like activity of lignans but also discusses the safe dosage of lignans at different life stages. In addition, this review also identified other types of bioactive compounds that can act synergistically with lignans to promote health. Studies have shown that lignan administration during pregnancy and lactation reduces the risk of breast cancer in offspring. Further studies are needed to investigate the estrogenic safety effects of lignan on pregnant women and children. Whether lignans combine with other nutrients in complex food substrates to produce synergistic effects remains to be investigated. This review provides a basis for future studies on the safe dose of lignan and recommended dietary intake of lignan. We believe that the acquired as discussed here has implications for developing dietary therapies that can promote host nutrition and modulate estrogenic diseases.

Review on the effect of chemotherapy on the intestinal barrier: Epithelial permeability, mucus and bacterial translocation

Chemotherapy kills fast-growing cells including gut stem cells. This affects all components of the physical and functional intestinal barrier, i.e., the mucus layer, epithelium, and immune system. This results in an altered intestinal permeability of toxic compounds (e.g., endotoxins) as well as luminal bacterial translocation into the mucosa and central circulation. However, there is uncertainty regarding the relative contributions of the different barrier components for the development of chemotherapy-induced gut toxicity. This review present an overview of the intestinal mucosal barrier determined with various types of molecular probes and methods, and how they are affected by chemotherapy based on reported rodent and human data. We conclude that there is overwhelming evidence that chemotherapy increases bacterial translocation, and that it affects the mucosal barrier by rendering the mucosa more permeable to large permeability probes. Chemotherapy also seems to impede the intestinal mucus barrier, even though this has been less clearly evaluated from a functional standpoint but certainly plays a role in bacteria translocation. Combined, it is however difficult to outline a clear temporal or succession between the different gastrointestinal events and barrier functions, especially as chemotherapy-induced neutropenia is also involved in intestinal immunological homeostasis and bacterial translocation. A thorough characterization of this would need to include a time dependent development of neutropenia, intestinal permeability, and bacterial translocation, ideally after a range of chemotherapeutics and dosing regimens.

Blunting ROS/TRPML1 pathway protects AFB1-induced porcine intestinal epithelial cells apoptosis by restoring impaired autophagic flux

Aflatoxin B1 (AFB1) is a stable mycotoxin that contaminates animal feed on a large scale and causes severe damage to intestinal cells, induces inflammation and stimulates autophagy. Transient receptor potential mucolipin subfamily 1 (TRPML1) is a regulatory factor of autophagy, but the underlying mechanisms of TRPML1-mediated autophagy in AFB1 intestine toxicity remain elucidated. In the present study, AFB1 (0, 5, 10 μg/mL) was shown to reduce cell viability, increase reactive oxygen species (ROS) accumulation and apoptosis rate. Additionally, AFB1 caused structural damage to mitochondria and lysosomes and increased autophagosomes numbers. Furthermore, AFB1 promoted Ca²⁺ release by activating the TRPML1 channel, stimulated the expression of autophagy-related proteins, and induced autophagic flux blockade. Moreover, pharmacological inhibition of autophagosome formation by 3-methyladenine attenuated AFB1-induced apoptosis by downregulating the levels of TRPML1 and ROS, whereas blockade of autophagosome-lysosomal fusion by chloroquine alleviated AFB1-induced apoptosis by upregulating TRPML1 expression and exacerbating ROS accumulation. Intriguingly, blocking AFB1-induced autophagic flux generated ROS- and TRPML1-dependent cell death, as shown by the decreased apoptosis in the presence the free radical scavenger N-Acetyl-L-cysteine and the TRPML1 inhibitor ML-SI1. Overall, these results showed that AFB1 promoted apoptosis of IPEC-J2 cells by disrupting autophagic flux through activation of the ROS/TRPML1 pathway.

Paraprobiotic Lacticaseibacillus rhamnosus Protects Intestinal Damage in an Experimental Murine Model of Mucositis

Intestinal mucositis (IM) is a common side effect resulting from cancer treatment. However, the management so far has not been very effective. In the last years, the role of the gut microbiota in the development and severity of mucositis has been studied. Therefore, the use of probiotics and paraprobiotics could have a potential therapeutic effect on IM. The aim of our study was to investigate the impact of the administration of Lacticaseibacillus rhamnosus (L. rhamnosus) CGMCC1.3724 and the paraprobiotic on IM in mice. For 13 days, male Balb/c mice were divided into six groups: control (CTL) and mucositis (MUC)/0.1 mL of saline; CTL LrV and MUC LrV/0.1 mL of 10⁸ CFU of viable Lr; CTL LrI and MUC LrI/0.1 mL of 10⁸ CFU of inactivated Lr. On the 10th day, mice from the MUC, MUC LrV, and MUC LrI groups received an intraperitoneal injection (300 mg/kg) of 5-fluorouracil to induce mucositis. The results showed that the administration of the chemotherapeutic agent increased the weight loss and intestinal permeability of the animals in the MUC and MUC LrV groups. However, administration of paraprobiotic reduced weight loss and maintained PI at physiological levels. The paraprobiotic also preserved the villi and intestinal crypts, reduced the inflammatory infiltrate, and increased the mucus secretion, Muc2 gene expression, and Treg cells frequency.

Endogenous small intestinal microbiome determinants of transient colonisation efficiency by bacteria from fermented dairy products: a randomised controlled trial

BACKGROUND

The effects of fermented food consumption on the small intestine microbiome and its role on host homeostasis are largely uncharacterised as our knowledge on intestinal microbiota relies mainly on faecal samples analysis. We investigated changes in small intestinal microbial composition and functionality, short chain fatty acid (SCFA) profiles, and on gastro-intestinal (GI) permeability in ileostomy subjects upon the consumption of fermented milk products.

RESULTS

We report the results from a randomised, cross-over, explorative study where 16 ileostomy subjects underwent 3, 2-week intervention periods. In each period, they consumed either milk fermented by Lacticaseibacillus rhamnosus CNCM I-3690, or milk fermented by Streptococcus thermophilus CNCM I-1630 and Lactobacillus delbrueckii subsp. bulgaricus CNCM I-1519, or a chemically acidified milk (placebo) daily. We performed metataxonomic, metatranscriptomic analysis, and SCFA profiling of ileostomy effluents as well as a sugar permeability test to investigate the microbiome impact of these interventions and their potential effect on mucosal barrier function. Consumption of the intervention products impacted the overall small intestinal microbiome composition and functionality, mainly due to the introduction of the product-derived bacteria that reach in several samples 50% of the total microbial community. The interventions did not affect the SCFA levels in ileostoma effluent, or gastro-intestinal permeability and the effects on the endogenous microbial community were negligible. The impact on microbiome composition was highly personalised, and we identified the poorly characterised bacterial family, Peptostreptococcaceae, to be positively associated with a low abundance of the ingested bacteria. Activity profiling of the microbiota revealed that carbon- versus amino acid-derived energy metabolism of the endogenous microbiome could be responsible for the individual-specific intervention effects on the small intestine microbiome composition and function, reflected also on urine microbial metabolites generated through proteolytic fermentation.

CONCLUSIONS

The ingested bacteria are the main drivers of the intervention effect on the small intestinal microbiota composition. Their transient abundance level is highly personalised and influenced by the energy metabolism of the ecosystem that is reflected by its microbial composition ( http://www.

CLINICALTRIALS

gov , ID NCT NCT02920294). Video Abstract.

Effects of Hydrogen Peroxide-Induced Oxidative Stress on Intestinal Morphology, Redox Status, and Related Molecules in Squabs

The purpose of this study was to evaluate the potential effect of oxidative stress on the intestine of squabs, and to explore the molecular mechanisms. A total of 360 1-day-old squabs were divided evenly into five different groups (n = 72/group): control, negative control, low, medium, and high dose groups. On the 3rd, 5th, and 7th days, squabs in the control group were not effectively treated and the negative control group were intraperitoneally injected with normal saline, whereas the H₂O₂ group was injected with H₂O₂ of 2.0, 2.5, and 3.0 mmol/kg BW respectively. On the 21st day, the serum and duodenum were collected for further analysis. The results indicated that, compared with the control group, H₂O₂ caused squabs weight loss and intestinal morphology damage, and these effects were enhanced with an increase in dose. Further examination revealed that the contents of oxidative stress markers in both the serum and duodenum of the H₂O₂ group were significantly enhanced as the dose was increased. In addition, H₂O₂ exposure also resulted in the lower mRNA expression of Occludin, ZO-1, Beclin1, Atg5, and Caspase-3, but the expression of Claudin2 and Bcl-2 was decreased in comparison to the control group. These findings suggested that duodenal oxidative damage was accompanied by weight loss, changes in intestinal morphology, redox status imbalance, apoptosis as well as autophagy of intestinal cells, with, effects of 3.0 mmol/kg BW of H₂O₂ being the most severe.

Effects of N-acetylcysteine on the inflammatory response and bacterial translocation in a model of intestinal obstruction and ischemia in rats

PURPOSE

To evaluate effect of N-acetylcysteine (NAC) associated with Ringer lactate or hypertonic saline in inflammation and bacterial translocation on experimental intestinal obstruction (IO).

METHODS

Wistar rats was subjected to IO. Six or 24 hours after, rats were subjected to enterectomy and fluid resuscitation: IO, RL (subjected to the same procedures but with fluid resuscitation using Ringer's lactate solution); RLNAC (added NAC to Ringer's solution); and HSNAC (surgical procedure + fluid reposition with 7.5% hypertonic saline and NAC). After 24 h, tissues were collected to cytokines, bacterial translocation, and histological assessments.

RESULTS

In kidney, interleukin-1beta (IL-1beta) was lower in the groups with fluid resuscitation compared to IO group. The RLNAC showed lower levels compared to the RL. Interleukin-6 (IL-6), interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-alpha), and (IFN-gamma) were lower in the treatment groups than in IO. In lung, IL-1beta and IL-6 were lower in RLNAC compared to IO. IL-10 was lower in RL, RLNAC and HSNAC compared to IO. TNF-alpha was higher in HSNAC compared to both RL and RLNAC. Bacterial translocation was observed in all animals of IO group. In kidneys, inflammation and congestion degrees were lower in HSNAC compared to RL. In lungs, inflammation levels were higher in RLNAC compared with the sham group.

CONCLUSIONS

The data indicates that NAC associated with RL can promote a decrease in the inflammatory process in the kidneys and lungs in rats, following intestinal obstruction and ischemia in rats.

L. rhamnosus CNCM I-3690 survival, adaptation, and small bowel microbiome impact in human

Fermented foods and beverages are a significant source of dietary bacteria that enter the gastrointestinal (GI) tract. However, little is known about how these microbes survive and adapt to the small intestinal environment. Colony-forming units (CFU) enumeration and viability qPCR of Lacticaseibacillus rhamnosus CNCM I-3690 in the ileal effluent of 10 ileostomy subjects during 12-h post consumption of a dairy product fermented with this strain demonstrated the high level of survival of this strain during human small intestine passage. Metatranscriptome analyses revealed the in situ transcriptome of L. rhamnosus in the small intestine, which was contrasted with transcriptome data obtained from in vitro cultivation. These comparative analyses revealed substantial metabolic adaptations of L. rhamnosus during small intestine transit, including adjustments of carbohydrate metabolism, surface-protein expression, and translation machinery. The prominent presence of L. rhamnosus in the effluent samples did not elicit an appreciable effect on the composition of the endogenous small intestine microbiome, but significantly altered the ecosystem's overall activity profile, particularly of pathways associated with carbohydrate metabolism. Strikingly, two of the previously recognized gut-brain metabolic modules expressed in situ by L. rhamnosus (inositol degradation and glutamate synthesis II) are among the most dominantly enriched activities in the ecosystem's activity profile. This study establishes the survival capacity of L. rhamnosus in the human small intestine and highlights its functional adjustment in situ, which we postulate to play a role in the probiotic effects associated with this strain.

Dihydromyricetin Attenuates High-Intensity Exercise-Induced Intestinal Barrier Dysfunction Associated with the Modulation of the Phenotype of Intestinal Intraepithelial Lymphocytes

BACKGROUND

Exercise-induced gastrointestinal syndrome (GIS) has symptoms commonly induced by strenuous sports. The study aimed to determine the effect of dihydromyricetin (DHM) administration on high-intensity exercise (HIE)-induced intestinal barrier dysfunction and the underlying mechanism involved with intestinal intraepithelial lymphocytes (IELs).

METHODS

The HIE model was established with male C57BL/6 mice using a motorized treadmill for 2 weeks, and DHM was given once a day by oral gavage. After being sacrificed, the small intestines of the mice were removed immediately.

RESULTS

We found that DHM administration significantly suppressed HIE-induced intestinal inflammation, improved intestinal barrier integrity, and inhibited a HIE-induced increase in the number of IELs and the frequency of CD8αα⁺ IELs. Meanwhile, several markers associated with the activation, gut homing and immune functions of CD8αα⁺ IELs were regulated by DHM. Mechanistically, luciferase reporter assay and molecular docking assay showed DHM could activate the aryl hydrocarbon receptor (AhR).

CONCLUSIONS

These data indicate that DHM exerts a preventive effect against HIE-induced intestinal barrier dysfunction, which is associated with the modulation of the quantity and phenotype of IELs in the small intestine. The findings provide a foundation to identify novel preventive strategies based on DHM supplementation for HIE-induced GIS.

The Chinese Herbal Formula Huoxiang Zhengqi Dropping Pills Prevents Acute Intestinal Injury Induced by Heatstroke by Increasing the Expression of Claudin-3 in Rats

Intestinal injury has been regarded as an important causative factor for systemic inflammation during heatstroke, and maintaining intestinal integrity has been a potential target for the prevention of HS. Huoxiang Zhengqi Dropping Pills (HZPD) is a modern preparation of Huoxiang Zhengqi and widely used to prevent HS. The present study aims to explore the protective effect of HZDP on intestinal injury during heatstroke and analyze its potential pharmacodynamic basis. Male rats in the control and HS groups were given normal saline, and those in the HZDP groups were given HZDP (0.23, 0.46, and 0.92 g/kg) before induction of HS. Serum contents of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), intestinal fatty acid-binding protein (iFABP), and diamine oxidase (DAO) were determined using ELISA. Histopathology of intestinal injury was observed following H&E staining. The expression of claudin-3 was determined using western blot, immunohistochemistry, and immunofluorescence techniques. Moreover, network pharmacological tools were used to analyze the potential pharmacodynamic basis and the mechanism of HZDP. Treatment with HZDP significantly prolonged the time to reach Tc. Compared with the control group, the contents of TNF-α, IL-6, iFABP, and DAO in HS rats increased markedly. HZDP treatments reduced these levels significantly, and the effects in the middle dose group (0.46 g/kg) were most obvious. HZDP also attenuated intestinal injury and significantly reversed the decrease in claudin-3 expression. Bioinformatics analysis suggested that 35 active ingredients and 128 target genes of HZDP were screened from TCMSP and 93 target genes intersected with heatstroke target genes, which were considered potential therapeutic targets. TNF-α and IL-6 were the main inflammatory target genes of HZDP correlated with HS. These results indicated that HZDP effectively protected intestinal barrier function and prevented acute intestinal injury by increasing the expression of claudin-3 in rats, eventually improving heat resistance.

Dietary Component-Induced Inflammation and Its Amelioration by Prebiotics, Probiotics, and Synbiotics

A balanced diet with many dietary components maintains immune homeostasis directly by interacting with innate and adaptive immune components or indirectly through gut microbiota and their metabolites. Dietary components may inhibit pro-inflammatory mediators and promote anti-inflammatory functions or vice versa. Western diets with imbalanced dietary components skew the immune balance toward pro-inflammation and induce intestinal inflammation, consequently leading to many intestinal and systemic inflammatory diseases like ulcerative colitis, Crohn's disease, irritable bowel syndrome, cardiovascular problems, obesity, and diabetes. The dietary component-induced inflammation is usually chronic in nature and frequently caused or accompanied by alterations in gut microbiota. Therefore, microbiome-targeted therapies such as probiotics, prebiotics and synbiotics hold great potentials to amend immune dysregulation and gut dysbiosis, preventing and treating intestinal and systemic inflammatory diseases. Probiotics, prebiotics and synbioitcs are progressively being added to foods and beverages, with claims of health benefits. However, the underlining mechanisms of these interventions for preventing and treating dietary component-induced inflammation are still not very clear. In addition, possibly ineffective or negative consequences of some probiotics, prebiotics and synbiotics call for stringent testing and regulation. Here, we will first briefly review inflammation, in terms of its types and the relationship between different dietary components and immune responses. Then, we focus on current knowledge about the direct and indirect effects of probiotics, prebiotics and synbiotics on intestinal and systemic inflammation. Understanding how probiotics, prebiotics and synbiotics modulate the immune system and gut microbiota will improve our strategies for preventing and treating dietary component-induced intestinal inflammation and inflammatory diseases.

Lactobacillus delbrueckii CIDCA 133 Ameliorates Chemotherapy-Induced Mucositis by Modulating Epithelial Barrier and TLR2/4/Myd88/NF-κB Signaling Pathway

Intestinal mucositis promoted by the use of anticancer drugs is characterized by ulcerative inflammation of the intestinal mucosa, a debilitating side effect in cancer patients undergoing treatment. Probiotics are a potential therapeutic option to alleviate intestinal mucositis due to their effects on epithelial barrier integrity and anti-inflammatory modulation. This study investigated the health-promoting impact of Lactobacillus delbrueckii CIDCA 133 in modulating inflammatory and epithelial barrier markers to protect the intestinal mucosa from 5-fluorouracil-induced epithelial damage. L. delbrueckii CIDCA 133 consumption ameliorated small intestine shortening, inflammatory cell infiltration, intestinal permeability, villus atrophy, and goblet cell count, improving the intestinal mucosa architecture and its function in treated mice. Upregulation of Muc2, Cldn1, Hp, F11r, and Il10, and downregulation of markers involved in NF-κB signaling pathway activation (Tlr2, Tlr4, Nfkb1, Il6, and Il1b) were observed at the mRNA level. This work suggests a beneficial role of L. delbrueckii strain CIDCA 133 on intestinal damage induced by 5-FU chemotherapy through modulation of inflammatory pathways and improvement of epithelial barrier function.

Oligosaccharides derived from Lycium barbarum ameliorate glycolipid metabolism and modulate the gut microbiota community and the faecal metabolites in a type 2 diabetes mouse model: metabolomic bioinformatic analysis

Herein, we assessed the effects of Lycium barbarum oligosaccharides (LBO) on the intestinal microenvironment of a type 2 diabetes (T2D) mouse model through gut microbiome and metabolomics analysis. We set high (300 mg kg^-1), medium (200 mg kg^-1), and low (100 mg kg^-1) doses of LBO for intervention once a day for 4 weeks. The results showed that the intervention effect of the medium-dose group was the most significant. It reduced the symptoms of hyperglycemia, inflammation, insulin resistance, and lipid accumulation in the T2D mouse model. It restored the structure of damaged tissues and cells, such as the pancreas, liver, and kidneys. LBO increased the relative abundance of beneficial bacteria, such as Lactobacillus, Bacteroides, Prevotella, and Akkermansia, and maintained intestinal barrier integrity. The faecal metabolic map showed that the contents of glycogen amino acids, such as proline, serine, and leucine, increased. The contents of cholic, capric, and dodecanoic acid decreased. In summary, we may suggest that LBO can be used as a prebiotic for treating T2D.

Probiotics Exhibit Strain-Specific Protective Effects in T84 Cells Challenged With Clostridioides difficile-Infected Fecal Water

Clostridioides difficile infection (CDI) is frequently associated with intestinal injury and mucosal barrier dysfunction, leading to an inflammatory response involving neutrophil localization and upregulation of pro-inflammatory cytokines. The severity of clinical manifestations is associated with the extent of the immune response, which requires mitigation for better clinical management. Probiotics could play a protective role in this disorder due to their immunomodulatory ability in gastrointestinal disorders. We assessed five single-strain and three multi-strain probiotics for their ability to modulate CDI fecal water (FW)-induced effects on T84 cells. The CDI-FW significantly (p < 0.05) decreased T84 cell viability. The CDI-FW-exposed cells also exhibited increased pro-inflammatory cytokine production as characterized by interleukin (IL)-8, C-X-C motif chemokine 5, macrophage inhibitory factor (MIF), IL-32, and tumor necrosis factor (TNF) ligand superfamily member 8. Probiotics were associated with strain-specific attenuation of the CDI-FW mediated effects, whereby Saccharomyces boulardii CNCM I-1079 and Lacticaseibacillus rhamnosus R0011 were most effective in reducing pro-inflammatory cytokine production and in increasing T84 cell viability. ProtecFlor™, Lactobacillus helveticus R0052, and Bifidobacterium longum R0175 showed moderate effectiveness, and L. rhamnosus GG R0343 along with the two other multi-strain combinations were the least effective. Overall, the findings showed that probiotic strains possess the capability to modulate the CDI-mediated inflammatory response in the gut lumen.

Immunological and Metabolic Alterations in Esophageal Cancer

Esophageal cancer is one of the most common types of gastrointestinal malignancies that is encountered. It has a global distribution and affects males and females and is linked to significant morbidity and mortality. The mechanisms underlying pathophysiology are multifactorial and involve the interaction of genetic and environmental factors. This review article describes the immunological and metabolic changes that occur in malignancy of the esophagus.

L-citrulline enriched fermented milk with Lactobacillus helveticus attenuates dextran sulfate sodium (DSS) induced colitis in mice

Inflammatory bowel disease (IBD) is a group of chronic inflammatory gastrointestinal diseases that causes worldwide suffering. L. helveticus is a probiotic that can enhance intestinal barrier function via alleviation of excessive inflammatory response. Citrulline, a functional amino acid, has been reported to stimulate muscle synthesis and to function with a prebiotic-like action with certain Lactobacillus strains. The aim of this study was to investigate the potential synergistic effect of combining L. helveticus and citrulline on protection against damage induced by dextran sulfate sodium (DSS) in a mouse model. 6-week-old male C57BL/6J mice were fed with DSS water and randomly divided for administering with different milk treatments: 1) plain milk (control or DSS control), 2) 1% (w/v) citrulline enriched milk (Cit_milk), 3) milk fermented with L. helveticus (LHFM) and 4) DSS+milk fermented with L. helveticus with 1% (w/v) citrulline (Cit_LHFM). The treatment effects on the survival and macroscopic and microscopic signs were examined. All treatments presented different degrees of protective effects on attenuating the damages induced by DSS. All treatments reduced the body weight loss, disease activity index (DAI), histological scores, pro-inflammatory cytokine expression (IL-6, TNF-α and IFN-γ) and production (IL-4) (all P <0.05) and the tight junction (TJ) protein (zonula occluden-1 (ZO-1) expression. LHFM and Cit_LHFM improved survival rate (both at P<0.05). Particularly, Cit_LHFM showed greater effects on protecting the damages induced by DSS, especially in ameliorating colonic permeability, TJ protein (ZO-1, occludin and claudin-1) expression and distribution as well as in reducing IL-4 and IL-17 expression (all P <0.05). Our findings suggested that the combination of and citrulline had significant synergistic effect on protecting against injury from DSS-induced colitis. Therefore, citrulline enriched L. helveticus fermented milk is suggested to be a potential therapy for treating IBD.

Plasma metabolites associated with physiological and biochemical indexes indicate the effect of caging stress on mallard ducks (Anas platyrhynchos)

Objective

Cage rearing has critical implications for the laying duck industry because it is convenient for feeding and management. However, caging stress is a type of chronic stress that induces maladaptation. Environmental stress responses have been extensively studied, but no detailed information is available about the comprehensive changes in plasma metabolites at different stages of caging stress in ducks. We designed this experiment to analyze the effects of caging stress on performance parameters and oxidative stress indexes in ducks.

Methods

Liquid chromatography tandem mass spectrometry (LC/MS-MS) was used to determine the changes in metabolites in duck plasma at 5 (CR5), 10 (CR10), and 15 (CR15) days after cage rearing and traditional breeding (TB). The associated pathways of differentially altered metabolites were analyzed using Kyoto encyclopedia of genes and genomes (KEGG) database.

Results

The results of this study indicate that caging stress decreased performance parameters, and the plasma total superoxide dismutase levels were increased in the CR10 group compared with the other groups. In addition, 1,431 metabolites were detected. Compared with the TB group, 134, 381, and 190 differentially produced metabolites were identified in the CR5, CR10, and CR15 groups, respectively. The results of principal component analysis (PCA) show that the selected components sufficiently distinguish the TB group and CR10 group. KEGG analysis results revealed that the differentially altered metabolites in duck plasma from the CR5 and TB groups were mainly associated with ovarian steroidogenesis, biosynthesis of unsaturated fatty acids, and phenylalanine metabolism.

Conclusion

In this study, the production performance, blood indexes, number of metabolites and PCA were compared to determine effect of the caging stress stage on ducks. We inferred from the experimental results that caging-stressed ducks were in the sensitive phase in the first 5 days after caging, caging for approximately 10 days was an important transition phase, and then the duck continually adapted.

Antarctic Strain of Rhodotorula mucilaginosa UFMGCB 18,377 Attenuates Mucositis Induced by 5-Fluorouracil in Mice

Mucositis is one of the most strenuous side effects caused by chemotherapy drugs, such as 5-fluorouracil (5-FU), during the treatment of several types of cancers. The disease is so prevalent and aggressive that many patients cannot resist such symptoms. However, despite its frequency and clinical significance, there is no effective treatment to prevent or treat mucositis. Thus, the use of probiotics as an adjuvant for the treatment has gained prominence. In the present study, we evaluated the effectiveness of oral administration of the Antarctic strain of Rhodotorula mucilaginosa UFMGCB 18,377 as an alternative to minimize side effects of 5-FU-induced mucositis in mice. Body weight, food consumption, stool consistency, and presence of blood in the feces were assessed daily in mice orally treated or not with the yeast and submitted or not to experimental mucositis. Blood, bones, and intestinal tissues and fluid were used to determine intestinal permeability and immunological, microbiological, and histopathological parameters. Treatment with R. mucilaginosa UFMGCB 18,377 was able to decrease clinical signs of the disease, such as reduction of food intake and body weight loss, and also decreased the number of intestinal enterobacteria and intestinal length shortening. Additionally, treatment was able to decrease the levels of MPO and EPO activities and inflammatory infiltrates, as well as the histopathological lesions characteristic of mucositis in the jejunum and ileum. Results of the present study showed that the oral administration of R. mucilaginosa UFMGCB 18,377 protected mice against mucositis induced by 5-FU.

Immunomodulatory Effect of Lactobacillus casei in a Murine Model of Colon Carcinogenesis

We previously reported beneficial effects of the probiotic strain Lactobacillus casei 393 in hindering colon carcinogenesis in a 1,2-dimethylhydrazine (DMH)-induced BALB/c mouse model of colon cancer. In the present study, we investigated the effect of preventive administration of L. casei 393 on the levels of selected pro- and anti-inflammatory circulating cytokines, as well as subpopulations of splenic T cells. The resulting experimental data on IFNγ, TNFα, IL-10, and colon histological features demonstrated that administration of L. casei 2 weeks before DMH treatment impaired the pro-inflammatory effect of DMH, while maintaining the levels of the three cytokines as well as colon histology; it also modulated splenic CD4⁺, CD8⁺, and NK T cell subpopulations. The preventive administration of L. casei to DMH-treated mice increased IL-17A synthesis and Treg percentages, further indicating a tumor-protecting role. Together, the results suggest that the colon-cancer-protective properties of L. casei 393 involve the dampening of inflammation through cytokine homeostasis and the maintenance of a healthy T cell subpopulation dynamic. For these reasons, probiotics such as L. casei may contribute to the health of the host as they promote optimal control of the immune response. Further, they may be used as prophylactic agents in combination with standard therapies against colon cancer.

Unhealthy Lifestyle and Gut Dysbiosis: A Better Understanding of the Effects of Poor Diet and Nicotine on the Intestinal Microbiome

The study of the intestinal or gut microbiome is a newer field that is rapidly gaining attention. Bidirectional communication between gut microbes and the host can impact numerous biological systems regulating immunity and metabolism to either promote or negatively impact the host's health. Habitual routines, dietary choices, socioeconomic status, education, host genetics, medical care and environmental factors can all contribute to the composition of an individual's microbiome. A key environmental factor that may cause negative outcomes is the consumption of nicotine products. The effects of nicotine on the host can be exacerbated by poor dietary choices and together can impact the composition of the gut microbiota to promote the development of metabolic disease including non-alcoholic fatty liver disease. This review explores the contribution of nicotine, poor dietary choices and other unhealthy lifestyle factors to gut dysbiosis.

Chemotherapeutics-Induced Intestinal Mucositis: Pathophysiology and Potential Treatment Strategies

The gastrointestinal tract is particularly vulnerable to off-target effects of antineoplastic drugs because intestinal epithelial cells proliferate rapidly and have a complex immunological interaction with gut microbiota. As a result, up to 40-100% of all cancer patients dosed with chemotherapeutics experience gut toxicity, called chemotherapeutics-induced intestinal mucositis (CIM). The condition is associated with histological changes and inflammation in the mucosa arising from stem-cell apoptosis and disturbed cellular renewal and maturation processes. In turn, this results in various pathologies, including ulceration, pain, nausea, diarrhea, and bacterial translocation sepsis. In addition to reducing patient quality-of-life, CIM often leads to dose-reduction and subsequent decrease of anticancer effect. Despite decades of experimental and clinical investigations CIM remains an unsolved clinical issue, and there is a strong consensus that effective strategies are needed for preventing and treating CIM. Recent progress in the understanding of the molecular and functional pathology of CIM had provided many new potential targets and opportunities for treatment. This review presents an overview of the functions and physiology of the healthy intestinal barrier followed by a summary of the pathophysiological mechanisms involved in the development of CIM. Finally, we highlight some pharmacological and microbial interventions that have shown potential. Conclusively, one must accept that to date no single treatment has substantially transformed the clinical management of CIM. We therefore believe that the best chance for success is to use combination treatments. An optimal combination treatment will likely include prophylactics (e.g., antibiotics/probiotics) and drugs that impact the acute phase (e.g., anti-oxidants, apoptosis inhibitors, and anti-inflammatory agents) as well as the recovery phase (e.g., stimulation of proliferation and adaptation).

Adjunct therapy with probiotics for chronic urticaria in children: randomised placebo-controlled trial

Backgrounds

Chronic urticaria is a common disorder of the skin, characterised by recurrent skin wheals and angioedema. Recent reports have shown that altered diversity and composition of the gut microbiota may lead to imbalances in immune regulation, a causal factor in the occurrence of chronic urticaria.

Objective

This study aimed to evaluate the efficacy of the Yimingjia^® probiotic formula in the adjuvant treatment of chronic urticaria in children.

Methods

We enrolled 206 children with confirmed diagnoses of chronic urticaria and randomly assigned them to the treatment (n = 104) or placebo group (n = 102). The children in each group were treated with desloratadine dry suspension, and those in the treatment group also received Yimingjia^®. Clinical efficacy was evaluated at 1, 2 and 4 weeks.

Results

Clinical symptom scores did not differ significantly at weeks 1 and 2 (p > 0.05), but at 4 weeks, wheal size and attack frequency were significantly reduced in the treatment group (p = 0.049 and 0.03, respectively). The overall response rate (significant improvement + complete response) significantly differed between the treatment (80.8%) and placebo groups (62.5%) (χ² = 4.20, p = 0.04).

Conclusion

Adjunct therapy with Yimingjia^® was safe and effective at 4 weeks in the treatment of chronic urticaria in children. The study was registered under trial number NCT03328897.

Multidimensional Approach for Investigating the Effects of an Antibiotic-Probiotic Combination on the Equine Hindgut Ecosystem and Microbial Fibrolysis

The equine hindgut ecosystem is specialized in dietary fibers' fermentation to provide horses' energy and contribute to its health. Nevertheless, antibiotics are known to disrupt the hindgut microbiota, affecting the fibrolytic activity of bacteria and the intestinal immune balance, leading to diseases. This in vivo study used a general and comprehensive approach for characterizing the hindgut ecosystem of 9 healthy horses over 28 days in response to a 5-day challenge with oral trimethoprim-sulfadiazine (TMS), with a special emphasis on microbial fibrolytic activity and the host immune response. Horses were supplemented with two doses of Lactobacillus acidophilus, Ligilactobacillus salivarius (formerly L. salivarius), and Bifidobacterium lactis blend or a placebo in a 3 × 3 Latin square design. Changes in fecal microbiota were investigated using 16S rRNA sequencing. Clostridioides difficile was quantified in feces using quantitative polymerase chain reaction. Anaerobic microbiological culture was used to enumerate functional bacterial groups (cellulolytic, amylolytic, and lactic acid-utilizing). The environmental dimensions were assessed by measuring the concentrations of volatile fatty acids (VFAs) and lactic acid using biochemical methods, and changes in pH and dry matter weight. Systemic and local inflammation was evaluated by determination of cytokine and immunoglobulin (Ig)A concentrations in the serum and secretory IgA (SIgA) concentrations in the feces using immuno-enzymatic methods. Oral TMS treatment strongly altered the whole hindgut ecosystem by 2 days after the first administration. Bacterial diversity decreased in proportion to the relative abundance of fibrolytic genera, which coincided with the decrease in the concentration of cellulolytic bacteria. At the same time, the composition of microbiota members was reorganized in terms of relative abundances, probably to support the alteration in fibrolysis. C. difficile DNA was not found in these horses, but the relative abundances of several potential pathobiont genera increased. 2 days after the first TMS administration, fecal concentrations of VFAs and SIgA increased in parallel with fecal water content, suggesting an alteration of the integrity of the hindgut mucosa. Recovery in bacterial composition, functions, and immune biomarkers took 2-9 days after the end of TMS administration. Supplementation with this bacterial blend did not limit bacterial alteration but might have interesting mucosal immunomodulatory effects.

Aflatoxin B1 and Aflatoxin M1 Induce Compromised Intestinal Integrity through Clathrin-Mediated Endocytosis

With the growing diversity and complexity of diet, humans are at risk of simultaneous exposure to aflatoxin B1 (AFB1) and aflatoxin M1 (AFM1), which are well-known contaminants in dairy and other agricultural products worldwide. The intestine represents the first barrier against external contaminants; however, evidence about the combined effect of AFB1 and AFM1 on intestinal integrity is lacking. In vivo, the serum biochemical parameters related to intestinal barrier function, ratio of villus height/crypt depth, and distribution pattern of claudin-1 and zonula occluden-1 were significantly affected in mice exposed to 0.3 mg/kg b.w. AFB1 and 3.0 mg/kg b.w. AFM1. In vitro results on differentiated Caco-2 cells showed that individual and combined AFB1 (0.5 and 4 μg/mL) and AFM1 (0.5 and 4 μg/mL) decreased cell viability and trans-epithelial electrical resistance values as well as increased paracellular permeability of fluorescein isothiocyanate-dextran in a dose-dependent manner. Furthermore, AFM1 aggravated AFB1-induced compromised intestinal barrier, as demonstrated by the down-regulation of tight junction proteins and their redistribution, particularly internalization. Adding the inhibitor chlorpromazine illustrated that clathrin-mediated endocytosis partially contributed to the compromised intestinal integrity. Synergistic and additive effects were the predominant interactions, suggesting that these toxins are likely to have negative effects on human health.

Effects of gut microbiota on atherosclerosis through hydrogen sulfide

Cardiovascular diseases are the leading cause of death and morbidity worldwide. Atherosclerotic cardiovascular disease (ASCVD) is affected by both environmental and genetic factors. Microenvironmental disorders of the human gut flora are associated with a variety of health problems, not only gastrointestinal diseases, such as inflammatory bowel disease, but also extralintestinal organs. Hydrogen sulfide (H₂S) is the third gas signaling molecule other than nitric oxide and carbon monoxide. In the cardiovascular system, H₂S plays important roles in the regulation of blood pressure, angiogenesis, smooth muscle cell proliferation and apoptosis, anti-oxidative stress, cardiac functions. This review is aiming to explore the potential role of gut microbiota in the development of atherosclerosis through hydrogen sulfide production as a novel therapeutic direction for atherosclerosis.

Intake of Lactobacillus delbrueckii (pExu:hsp65) Prevents the Inflammation and the Disorganization of the Intestinal Mucosa in a Mouse Model of Mucositis

5-Fluorouracil (5-FU) is an antineoplastic drug that causes, as a side effect, intestinal mucositis, acute inflammation in the small bowel. The Heat Shock Protein (Hsp) are highly expressed in inflammatory conditions, developing an important role in immune modulation. Thus, they are potential candidates for the treatment of inflammatory diseases. In the mucositis mouse model, the present study aimed to evaluate the beneficial effect of oral administration of milk fermented by Lactobacillus delbrueckii CIDCA 133 (pExu:hsp65), a recombinant strain. This approach showed increased levels of sIgA in the intestinal fluid, reducing inflammatory infiltrate and intestinal permeability. Additionally, the histological score was improved. Protection was associated with a reduction in the gene expression of pro-inflammatory cytokines such as Tnf, Il6, Il12, and Il1b, and an increase in Il10, Muc2, and claudin 1 (Cldn1) and 2 (Cldn2) gene expression in ileum tissue. These findings are corroborated with the increased number of goblet cells, the electronic microscopy images, and the reduction of intestinal permeability. The administration of milk fermented by this recombinant probiotic strain was also able to reverse the high levels of gene expression of Tlrs caused by the 5-FU. Thus, the rCIDCA 133:Hsp65 strain was revealed to be a promising preventive strategy for small bowel inflammation.

Prophylactic and therapeutic supplementation using fructo-oligosaccharide improves the intestinal homeostasis after mucositis induced by 5- fluorouracil

The beneficial effects of prebiotic, such as fructo-oligosaccharides (FOS), in intestinal inflammation have been demonstrated in several studies. Herein, we evaluate whether joint treatment with FOS, both before and during mucositis, had additional beneficial effects and investigated the mechanisms underlying in the action of FOS on the intestinal barrier. BALB/c mice were randomly divided into five groups: CTR (without mucositis + saline solution), FOS (without mucositis + 6 % FOS), MUC (mucositis + saline solution), PT (mucositis + 6 % FOS supplementation before disease induction), and TT (mucositis + 6 % FOS supplementation before and during disease induction). Mucositis was induced by intraperitoneal injection (300 mg/kg) of 5-fluorouracil (5-FU). After 72 h, the animals were euthanized and intestinal permeability (IP), tight junction, bacterial translocation (BT), histology and morphometry, and immunoglobulin A secretory (sIgA), inflammatory infiltrate, and production of short-chain fatty acids (acetate, butyrate and propionate) were evaluated. The MUC group showed an increase in the IP, BT, and inflammatory infiltrate but a decrease in the tight junction expression and butyrate and propionate levels (P < 0.05). In the PT and TT groups, FOS supplementation maintained the IP, tight junction expression, and propionate concentration within physiologic levels, increased butyrate levels, and reduced BT and inflammatory infiltrate (P < 0.05). Total treatment with FOS (TT group) was more effective in maintaining histological score, morphometric parameters, and sIgA production. Thus, total treatment (prophylactic and therapeutic supplementation) with FOS was more effective than pretreatment alone, in reducing 5-FU-induced damage to the intestinal barrier.

Saccharomyces boulardii as therapeutic alternative in experimental giardiasis

AIMS

The objective of this study was to evaluate the effect of treatment with the probiotic Saccharomyces boulardii with or without metronidazole in experimental giardiasis.

METHODS AND RESULTS

The effect of treatment with S. boulardii with or without metronidazole on the intestinal mucosa, the antioxidant defence system and the parasitic load was determined in experimental giardiasis. Eight groups of animals with infection and/or treatment with the probiotic and/or drugs for 1 week after infection with Giardia lamblia were used. A reduction of approximately 90% in the parasitic load was observed in all the treated groups. Saccharomyces boulardii attenuated the damage caused by infection in the intestinal mucosa preserving its architecture and inhibiting the oxidative stress induced by parasite and metronidazole.

CONCLUSIONS

Saccharomyces boulardii was effective alone or in combination with metronidazole in resolving already established G. lamblia infection.

SIGNIFICANCE AND IMPACT OF THE STUDY

These results suggest the use of S. boulardii as an alternative treatment for giardiasis mainly in cases of resistance or intolerance to conventional treatment.

Yacón (Smallanthus sonchifolius) prevented inflammation, oxidative stress, and intestinal alterations in an animal model of colorectal carcinogenesis

BACKGROUND

Yacón (Smallanthus sonchifolius) roots store carbohydrate in the form of prebiotic fructooligosaccharides (FOS), which improve intestinal health. Yacon has the potential to prevent the intestinal barrier alterations associated with colorectal cancer (CRC). This study aimed to investigate the preventive effects of yacón flour (YF) on alterations promoted by CRC induced by 1,2-dimethylhydrazine in rats.

RESULTS

CRC increased tumor necrosis factor alpha levels (group CY = 10.2 ± 0.72; group C = 9.6 ± 1.0; group Y = 5.8 ± 0.54; group S = 5.95 ± 0.6 pg mL^-1 ) and short-chain fatty acid production, and decreased total antioxidant capacity (group CY = 4.7 ± 0.72; group C = 3.3 ± 0.3; group Y = 4.1 ± 0.47; group S = 6.7 ± 0.78 U mL^-1 ). Furthermore, YF treatment reduced intraluminal pH (group CY = 6.45 ± 0.47; group C = 7.65 ± 0.44; group Y = 6.75 ± 0.46; group S = 8.13 ± 0.2), lactulose/mannitol ratio, tumor necrosis factor-alpha (TNF-α)/interleukin (IL)-10 ratio, and increased secretory immunoglobulin A (group CY = 9.48 ± 1.46; group C = 10.95 ± 3.87; group Y = 15.95 ± 7.36; group S = 9.19 ± 1.52), but did not affect IL-10, IL-12, and TNF-α levels nor the IL-12/IL-10 ratio.

CONCLUSION

YF as a source of fructooligosaccharides may help to maintain the integrity of intestinal health, which is altered in induced CRC in rats. © 2020 Society of Chemical Industry.

Lactobacillus plantarum PMO 08 as a Probiotic Starter Culture for Plant-Based Fermented Beverages

Lactobacillus plantarum PMO 08 was evaluated as a starter culture for plant-based probiotic beverages. Its viability under various culture conditions and acidification ability in standardized tomato medium, fermentation parameters, and beverage properties were assessed. Lactobacillus plantarum PMO 08 could grow under various culture conditions; there was a high correlation between the incubation time to reach the optimal conditions and the inoculation concentration of lactic acid bacteria (LAB) (r² = 0.997). Acidity (0.958 ± 0.002%) and LAB count (9.78 ± 0.14 Log₁₀ CFU/mL) were significantly higher when fermented with L. plantarum than with the yogurt starter culture. A survival rate of 96% and 95% in artificial gastric juice and artificial intestinal juice, respectively, indicated that the probiotic requirements were met. The total polyphenol and glutamine content, and antioxidant activity increased after fermentation. The proline content significantly increased in L. plantarum PMO 08- fermented beverage. Thus, L. plantarum PMO 08 is an effective starter culture for non-dairy probiotic beverages whose functional quality may be improved by fermentation.

The Compromised Intestinal Barrier Induced by Mycotoxins

Mycotoxins are fungal metabolites that occur in human foods and animal feeds, potentially threatening human and animal health. The intestine is considered as the first barrier against these external contaminants, and it consists of interconnected physical, chemical, immunological, and microbial barriers. In this context, based on in vitro, ex vivo, and in vivo models, we summarize the literature for compromised intestinal barrier issues caused by various mycotoxins, and we reviewed events related to disrupted intestinal integrity (physical barrier), thinned mucus layer (chemical barrier), imbalanced inflammatory factors (immunological barrier), and dysfunctional bacterial homeostasis (microbial barrier). We also provide important information on deoxynivalenol, a leading mycotoxin implicated in intestinal dysfunction, and other adverse intestinal effects induced by other mycotoxins, including aflatoxins and ochratoxin A. In addition, intestinal perturbations caused by mycotoxins may also contribute to the development of mycotoxicosis, including human chronic intestinal inflammatory diseases. Therefore, we provide a clear understanding of compromised intestinal barrier induced by mycotoxins, with a view to potentially develop innovative strategies to prevent and treat mycotoxicosis. In addition, because of increased combinatorial interactions between mycotoxins, we explore the interactive effects of multiple mycotoxins in this review.

Anti-Inflammatory Potential of Cow, Donkey and Goat Milk Extracellular Vesicles as Revealed by Metabolomic Profile

In recent years, extracellular vesicles (EVs), cell-derived micro and nano-sized structures enclosed in a double-layer membrane, have been in the spotlight for their high potential in diagnostic and therapeutic applications. Indeed, they act as signal mediators between cells and/or tissues through different mechanisms involving their complex cargo and exert a number of biological effects depending upon EVs subtype and cell source. Being produced by almost all cell types, they are found in every biological fluid including milk. Milk EVs (MEVs) can enter the intestinal cells by endocytosis and protect their labile cargos against harsh conditions in the intestinal tract. In this study, we performed a metabolomic analysis of MEVs, from three different species (i.e., bovine, goat and donkey) by mass spectroscopy (MS) coupled with Ultrahigh-performance liquid chromatography (UHPLC). Metabolites, both common or specific of a species, were identified and enriched metabolic pathways were investigated, with the final aim to evaluate their anti-inflammatory and immunomodulatory properties in view of prospective applications as a nutraceutical in inflammatory conditions. In particular, metabolites transported by MEVs are involved in common pathways among the three species. These metabolites, such as arginine, asparagine, glutathione and lysine, show immunomodulating effects. Moreover, MEVs in goat milk showed a greater number of enriched metabolic pathways as compared to the other kinds of milk.

Water-Soluble Fiber from Bengkoang (Pachyrhizus erosus (L.) Urban) Tuber Modulates Immune System Activity in Male Mice

Our previous study showed that water-soluble fiber from bengkoang (Pachyrizus erosus (L.) Urban) fiber extract (BFE) and bengkoang fiber fraction B (BFE-B) have phagocytic activity and modulation of cytokine production in vitro. The present study evaluates the immunomodulatory effects of water-soluble fibers BFE and BFE-B on male mice induced by hepatitis B vaccine. Thirty mice were divided into six groups and induced by hepatitis B vaccine intraperitoneally on days 7 and 14. The mice were then treated with BFE, BFE-B, levamisole, or sodium carboxymethyl cellulose for 18 days. At the end of the treatments (day 19), phagocytic activity, lymphocyte proliferation, spleen index, cytokine, and immunoglobulin G (IgG) production were determined. The results showed that the water-soluble fiber treatment could significantly increase phagocytic capacity, nitric oxide production, and spleen index. However, BFE-B could modulate tumor necrosis factor (TNF)-α and interleukin (IL)-10 secretion, BFE demonstrated no such effect on cytokine production. Lymphocyte proliferation assay revealed that treatment with 50 mg/kg body weight (BW) BFE and 50 mg/kg BW BFE-B could significantly enhance lymphocyte proliferation. Treatment with 25 and 50 mg/kg BW BFE-B stimulated IgG production. In conclusion, BFE and BFE-B similarly have immunomodulatory effects on innate immune responses. BFE-B further demonstrated immunomodulatory effects on adaptive immune responses.

The interaction between microbiome and host central nervous system: the gut-brain axis as a potential new therapeutic target in the treatment of obesity and cardiometabolic disease

INTRODUCTION

The role of the intestinal microbiota in host cardiometabolic health and disease has gained significant attention over recent decades. Previous studies have shown effects on metabolic health through gut microbiota modulation; this suggests diverse interaction pathways that constitute the communication between gut microbiota and host central nervous system, the so-called gut-brain axis.

AREAS COVERED

This article provides an overview of the various mechanisms that may mediate the gut-brain axis. It places an emphasis on cardiometabolic health, including effects of short-chain fatty acids (SCFA), alterations in neurotransmitters and gut peptides and microbial effects on chronic inflammation and immune function. Moreover, this paper sheds light on whether these mechanisms afford therapeutic targets to promote metabolic health. To this end, a PubMed search with the terms 'gut microbiota,' 'obesity' and 'insulin sensitivity' was performed.

EXPERT OPINION

Many properties of the human gut microbiome are associated with the central regulation of appetite and metabolic status. Some of these relationships are causal and there are positive effects from certain intervention methods. Microbial manipulation may offer a means to prevent or treat obesity and associated co-morbidities. However, to establish direct causal relations between altered gut microbiota and metabolic disease, clinical intervention studies are necessary.

The magnitude of physical exercise-induced hyperthermia is associated with changes in the intestinal permeability and expression of tight junction genes in rats

We investigated whether the magnitude of exercise-induced hyperthermia influences intestinal permeability and tight junction gene expression. Twenty-nine male Wistar rats were divided into four groups: rest at 24 °C and exercise at 13 °C, 24 °C or 31 °C. The exercise consisted of a 90-min treadmill run at 15 m/min, and different ambient temperatures were used to produce distinct levels of exercise-induced hyperthermia. Before the experimental trials, the rats were treated by gavage with diethylenetriaminepentaacetic acid labeled with technetium-99 metastable as a radioactive probe. The rats' core body temperature (T_CORE) was measured by telemetry. Immediately after the trials, the rats were euthanized, and the intestinal permeability was assessed by measuring the radioactivity of blood samples. The mRNA levels of occludin and zonula occludens-1 (ZO-1) genes were determined in duodenum samples. Exercise at 24 °C increased T_CORE to values close to 39 °C, without changing permeability compared with the resting trial at the same environment. Meanwhile, rats' T_CORE exceeded 40 °C during exercise at 31 °C, leading to greater permeability relative to those observed after exercise in the other ambient temperatures (e.g., 0.0037%/g at 31 °C vs. 0.0005%/g at 13 °C; data expressed as medians; p < 0.05). Likewise, the rats exercised at 31 °C exhibited higher mRNA levels of ZO-1 and occludin genes than the rats exercised at 24 °C or 13 °C. The changes in permeability and gene expression were positively and significantly associated with the magnitude of hyperthermia. We conclude that marked hyperthermia caused by exercise in the warmer environment increases intestinal permeability and mRNA levels of tight junction genes.

Odd-numbered agaro-oligosaccharides alleviate type 2 diabetes mellitus and related colonic microbiota dysbiosis in mice

Agaro- and neoagaro-oligosaccharides with even-numbered sugar units possess a variety of biological activities. However, the effects of the odd-numbered oligosaccharides from Gracilaria agarose (OGAOs) on type 2 diabetes mellitus (T2DM) have not been reported. In this study, we aimed to evaluate the effects of OGAOs on anti-T2DM from different aspects. We found that OGAOs treatment could alleviate oxidative stress, inflammation, and the related hyperglycemia, insulin resistance, lipid accumulation, and obesity in high-fat diet (HFD) induced T2DM. Investigation of the underlying mechanism showed that colitis and colonic microbiota dysbiosis in T2DM mice were ameliorated after OGAOs treatment. First, OGAOs increased the expression of ZO-1, occludin, and AMPK, and suppressed the TLR4/MAPK/NF-κB pathway in colon indicating that OGAOs enhance intestinal integrity and conduct the anti-apoptosis effects to prevent the invasion of toxins and harmful microorganisms. Moreover, the relative abundance of Akkermansia was significantly upregulated in the gut microbiome of T2DM mice associated with a dramatic decrease of the relative abundance of Helicobacter, which are both beneficial for alleviating colitis and T2DM. In addition, Spearman's correlation analysis indicated that changes in the colonic microbiota could regulate oxidative stress, inflammation, and hyperlipidemia. In summary, the underlying mechanism of OGAOs on alleviating colitis and colonic microbiota dysbiosis in T2DM has been intensively studied, illustrating that OGAOs could be further developed as a potential pharmaceutical agent for T2DM.

Cocoa diet modulates gut microbiota composition and improves intestinal health in Zucker diabetic rats

Cocoa supplementation improves glucose metabolism in Zucker diabetic fatty (ZDF) rats via multiple mechanisms. Furthermore, cocoa rich-diets modify the intestinal microbiota composition both in humans and rats in healthy conditions. Accordingly, we hypothesized that cocoa could interact with the gut microbiota (GM) in ZDF rats, contributing to their antidiabetic effects. Therefore, here we investigate the effect of cocoa intake on gut health and GM in ZDF diabetic rats. Male ZDF rats were fed with standard (ZDF-C) or 10% cocoa-rich diet (ZDF-Co) during 10 weeks. Zucker Lean animals (ZL) received the standard diet. Colon tissues were obtained to determine the barrier integrity and the inflammatory status of the intestine and faeces were analysed for microbial composition, short-chain fatty acids (SCFA) and lactate levels. We found that cocoa supplementation up-regulated the levels of the tight junction protein Zonula occludens-1 (ZO-1) and the mucin glycoprotein and reduced the expression of pro-inflammatory cytokines such as tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6) and monocyte chemoattractant protein 1 (MCP-1) in the colon of ZDF diabetic animals. Additionally, cocoa modulated the microbial composition of the ZDF rats to values similar to those of the lean group. Importantly, cocoa treatment increased the relative abundance of acetate-producing bacteria such as Blautia and prevented the increase in the relative amount of lactate-producing bacteria (mainly Enterococcus and Lactobacillus genera) in ZDF diabetic animals. Accordingly, the total levels of SCFA (mainly acetate) increased significantly in the faeces of ZDF-Co diabetic rats. Finally, modified GM was closely associated with improved biochemical parameters related to glucose homeostasis and intestinal integrity and inflammation. These findings demonstrate for the first time that cocoa intake modifies intestinal bacteria composition towards a healthier microbial profile in diabetic animals and suggest that these changes could be associated with the improved glucose homeostasis and gut health induced by cocoa in ZDF diabetic rats.

Regulatory T Cells Could Improve Intestinal Barrier Dysfunction in Heatstroke

Intestinal barrier dysfunction plays a pivotal role in multiorgan dysfunction during heatstroke (HS). Neutrophils are involved in intestinal inflammation and thus dampen the mucosal integrity. Regulatory T cells (Tregs) have been shown to orchestrate neutrophils and thus sustain mucosal integrity in miscellaneous inflammation-related diseases. However, whether Tregs are involved in HS-induced intestinal barrier dysfunction remains unknown. Thus, we investigated whether Tregs could alleviate intestinal barrier dysfunction in mice. We found that HS could induce intestinal injury and mucosal barrier dysfunction 0, 24, and 72 h after heat stress. Flow cytometry revealed an increase of neutrophil infiltration and a decrease of Treg frequencies in the small intestinal epithelium 72 h after heat stress. Treg depletion starting 2 days before HS exacerbated intestinal damage and mucosal barrier dysfunction. Adoptive transfer of Tregs at 0 h improved intestinal injury and mucosal barrier dysfunction at 72 h. The manipulation of Tregs affected the neutrophil frequencies in the small intestinal epithelium 72 h after heat stress. Our study demonstrated that Tregs could improve HS-induced intestinal barrier dysfunction, probably via modulation of neutrophils in the intestine of mice during HS.

Intestinal Injury in Heat Stroke

BACKGROUND

Heat stroke is a life-threatening syndrome that is characterized by its severe clinical symptoms, rapid progression, and high rate of mortality. Recently, research has indicated that a dysfunctional intestinal epithelia barrier plays an important role in the pathophysiology of heat stroke. Protecting the intestines from heat stress had been identified as a potentially effective treatment for patients with heat stroke and may reduce the innate immune response caused by endotoxins in circulation.

OBJECTIVES

The aim of this review is to discuss this key event in heat stroke and to describe the mechanism during progression.

DISCUSSION

Direct injuries and secondary impairments of the intestine induced by heat stress are discussed; recent studies that refer to intestine-specific prevention and treatment in heat stroke and heat stress-induced injuries are also summarized.

CONCLUSIONS

A more detailed pathogenesis of heat stroke needs to be elucidated so that potentially effective means of treatment and prevention of heat stroke can be developed and studied.

Gastrointestinal microecology: a crucial and potential target in acute pancreatitis

In the early stage of acute pancreatitis (AP), abundant cytokines induced by local pancreatic inflammation enter the bloodstream, further cause systemic inflammatory response syndrome (SIRS) by "trigger effect", which eventually leads to multiple organ dysfunction syndrome (MODS). During SIRS and MODS, the intestinal barrier function was seriously damaged accompanied by the occurrence of gut-derived infection which forms a "second hit summit" by inflammatory overabundance. Gastrointestinal microecology, namely the biologic barrier, could be transformed into a pathogenic state, which is called microflora dysbiosis when interfered by the inflammatory stress during AP. More and more evidences indicate that gastrointestinal microflora dysbiosis plays a key role in "the second hit" induced by AP gut-derived infection. Therefore, the maintenance of gastrointestinal microecology balance is likely to provide an effective method in modulating systemic infection of AP. This article reviewed the progress of gastrointestinal microecology in AP to provide a reference for deeply understanding the pathogenic mechanisms of AP and identifying new therapeutic targets.

Grape peel powder promotes intestinal barrier homeostasis in acute TNBS-colitis: A major role for dietary fiber and fiber-bound polyphenols

Inflammatory bowel diseases are characterized by impaired intestinal barrier function. This study aimed to evaluate the effects of grape peel powder (GPP) and its bioactive rich-fractions on the barrier function and colonic injury in a model of colitis induced by 2,4,6 trinitrobenzene sulfonic acid (TNBS). Wistar rats received diets supplemented with either GPP (8%), extractable polyphenols (EP), non-extractable polyphenols-rich fraction (NEP-F), or polyphenols-poor, fiber-rich fraction (F) from grapes at amounts equivalent to the GPP group during 15 days before and for 7 days after colitis induction. NEP-F has decreased the extension of colonic lesion but the other grape peel bioactive fractions did not protect against macroscopic or microscopic colonic damage, EP diet increased macroscopic colonic damage. GPP, EP, and NEP-F reduced claudin-2 mRNA expression, whereas GPP and F fraction increased occludin and ZO-1 mRNA expression. All experimental diets reduced the colitis-triggered increase of MMP-9 mRNA expression. Colitis reduced by 30% the production of cecal short-chain fatty acids (SCFA). GPP and NEP-F completely protected against this effect, whereas F fraction was ineffective. Only GPP and NEP-F were able to decrease the upregulation of GRP94 mRNA triggered by colitis. Dietary fiber seems to reestablish the intestinal barrier function, whereas fiber-bound phenolics were able to restore cecal metabolism to produce beneficial metabolites like SCFA and to reduce the activation of the unfolded protein response.

Reduced Plasma Amino Acid Levels During Allogeneic Hematopoietic Stem Cell Transplantation Are Associated with Systemic Inflammation and Treatment-Related Complications

Patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT) are challenged by cytotoxic effects of the conditioning regimen, resulting in tissue damage, systemic inflammation, and increased metabolic demands for amino acids to regenerate damaged tissues, reconstitute hematopoietic cells, and establish antioxidant defenses. To date, few studies have addressed the role of plasma amino acid (PAA) levels during transplantation, and it remains unknown if amino acid deficiency can aggravate treatment-related morbidity. We determined plasma levels of the 23 human amino acids in 80 HSCT recipients (age 1.1 to 55.4 years) before conditioning and on days +7 and +21 post-transplant along with C-reactive protein (CRP) and IL-6 levels on day +7. Significant changes were observed in plasma concentrations of several human amino acids during HSCT. On day +7, numerous amino acids were inversely correlated with both CRP and IL-6, including glutamic acid, serine, alanine, glutamine, arginine, cysteine, glycine, histidine, lysine, tryptophan, threonine, taurine, proline, and methionine (r = -.22 to -.66; all P < .05). Patients who developed sinusoidal obstruction syndrome (SOS) had significantly lower mean total PAA levels compared with patients without SOS (2013 ng/L [95% confidence interval (CI), 1709 to 2318 ng/L] versus 2706 ng/L [95% CI, 2261 to 3150 ng/L]; P = .006), along with lower individual levels of glutamic acid, serine, arginine, glycine, lysine, valine, tryptophan, threonine, and proline on day +7 (all P < .05). Patients with severe acute graft-versus-host disease had a lower mean total PAA level (1922 ng/L [95% CI, 1738 to 2106 ng/L] versus 2649 ng/L [95% CI, 2244 to 3055 ng/L]; P = .014) and lower levels of serine, glutamine, cysteine, glycine, lysine, and threonine on day +7 (all P < .05). These results indicate a relationship between low concentrations of certain amino acids and the risk of treatment-related complications.

Targeting regulation of tryptophan metabolism for colorectal cancer therapy: a systematic review

Colorectal cancer (CRC) is one of the most malignant cancers resulting from abnormal metabolism alterations. As one of the essential amino acids, tryptophan has a variety of physiological functions, closely related to regulation of immune system, central nervous system, gastrointestinal nervous system and intestinal microflora. Colorectal cancer, a type of high-grade malignancy disease, stems from a variety of factors and often accompanies inflammatory reactions, dysbacteriosis, and metabolic disorders. Colorectal cancer accompanies inflammation and imbalance of intestinal microbiota and affects tryptophan metabolism. It is known that metabolites, rate-limiting enzymes, and ARH in tryptophan metabolism are associated with the development of CRC. Specifically, IDO1 may be a potential therapeutic target in colorectal cancer treatment. Furthermore, the reduction of tryptophan amount is proportional to the poor quality of life for colorectal cancer patients. This paper aims to discuss the role of tryptophan metabolism in a normal organism and investigate the relationship between this amino acid and colorectal cancer. This study is expected to provide theoretical support for research related to targeted therapy for colorectal cancer. Furthermore, strategies that modify tryptophan metabolism, effectively inhibiting tumor progression, may be more effective for CRC treatment.

Colorectal cancer (CRC) is one of the most malignant cancers resulting from abnormal metabolism alterations.