Hypericumsampsonii attenuates inflammation in mice with ulcerative colitis via regulation of PDE4/PKA/CREB signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Hypericum sampsonii Hance (Yuanbaocao), a traditional herbal medicine with various pharmacological properties, is traditionally used to treat diarrhea and enteritis in China for hundreds of years. Investigations have uncovered its anti-inflammatory effects and corresponding bioactive constituents in H. sampsonii, however, the mechanisms of action for the treatment of enteritis are still unclear. AIMS OF THE STUDY: This study aims to investigate the therapeutic effects and molecular mechanisms of H. sampsonii in a dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) mice model. MATERIALS AND METHODS: The major ingredients of the ethyl acetate extract (HS) in H. sampsonii were analyzed by UPLC-QTOF-MS. The inflammatory state of UC mice was caused by 3% DSS once daily for seven days. During DSS treatment, the mice in the positive drug group and the other three groups were orally administered 5-ASA (positive control) or HS daily. After treatment with HS or 5-ASA for a week, colonic pathological observation and the molecular biological index were performed for therapeutic evaluation, including visual inspection in the length and weight of colons and spleens, pathological morphology by hematoxylin and eosin (HE) staining, determination of oxidative markers, inflammatory cytokines and tumor necrosis factor-alpha (TNF-α) levels in colonic tissues as well as spleen index. Gene expression levels of inflammatory cytokines, antioxidant enzymes and PDE4 were detected using kits and PCR, while the expression of colonic tight junction proteins and relative signals of PKA/CREB signaling pathway were analyzed by Western blot. RESULTS: The main components in HS were found to be polycyclic polyprenylated acylphloroglucinols (PPAPs). HS distinctly alleviated DSS-stimulated UC-like lesions symptoms as evidenced by a significant recovery from body weight, colon lengths, and histological injuries of colons. HS reduced the accumulation of pro-inflammatory cytokines and improved the mRNA level of IL-10. Simultaneously, the colonic mRNA expression levels of IL-1ß, IL-17, iNOS and COX-2 were all significantly suppressed by HS in a dose-dependent manner. Furthermore, HS restored the protein expression of tight junction-associated protein (ZO-1 and occluding). Besides, HS significantly inhibited the protein level of PDE4 and decreased the expressions of PKA and phosphorylated CREB. CONCLUSION: This is the first work about main composition and anti-UC effect of Hypericum sampsonii Hance. For the first time, this study reveals HS is not toxic in a single dose and exert significantly protective effect in DSS-colitis mice. The underlying mechanisms may involve the improvement to inflammatory status, the protection for intestinal barrier function, the inhibition of PDE4, and the activation of PKA/CREB signaling pathway. This study provided an experimental basis for the traditional application of H. sampsonii Hance in the treatment of diarrhea and dysentery.

Protective effects of Brownea grandiceps (Jacq.) against ϒ-radiation-induced enteritis in rats in relation to its secondary metabolome fingerprint.

Radiation enteritis is the most common complication of radiotherapy in patients with pelvic malignancies. Thus, the radioprotective activity of the total hydro-alcoholic extract (BGE) and the ethyl acetate soluble fraction (EAF) of Brownea grandiceps leaves was evaluated against ϒ-radiation-induced enteritis in rats. (BGE) and (EAF) were characterized using HPLC-PDA-ESI-MS/MS analysis. The total phenolic and flavonoid contents were also quantified. In vivo administration of (BGE) (400 mg/kg) and (EAF) (200 & 400 mg/kg) prevented intestinal injury and maintained the mucosal integrity of irradiated rats through increasing villi length and promoting crypt regeneration. Also, (EAF) showed more potent antioxidant activity than (BGE) through reduction of MDA level and enhancement of GSH content and catalase enzyme activity. (BGE) and (EAF) down-regulated intestinal NF-κB expression leading to diminished expression of downstream inflammatory cytokine TNF-α. Moreover, (EAF) markedly reduced the expression of profibrotic marker TGF-ß1. Seventy-nine compounds were tentatively identified, including flavonoids, proanthocyanidins, polar lipids and phenolic acids. (EAF) showed significantly higher total phenolic and flavonoid contents, as compared to (BGE). Results revealed remarkable radioprotective activity of (BGE) and (EAF), with significantly higher activity for (EAF). The chemical constituents of (BGE) and (EAF) strongly supported their radioprotective activity. To the best of our knowledge, the present study describes for the first time the radioprotective activity of B. grandiceps leaves in relation to its secondary metabolome fingerprint; emphasizing the great promise of B. grandiceps leaves, especially (EAF), to be used as natural radio-protective agent.

AMPK activation by ozone therapy inhibits tissue factor-triggered intestinal ischemia and ameliorates chemotherapeutic enteritis.

Chemotherapeutic enteritis is a major dose-limiting adverse reaction to chemotherapy, with few effective drugs in clinic. Intestinal ischemic injury plays prominent role in chemotherapeutic enteritis clinically. However, mechanism is not clear. In this article, irinotecan (CPT-11) was used to establish chemotherapeutic enteritis mice model. Western blotting, gelatin zymography, immunohistochemistry (IHC), Laser Doppler flowmetry (LDF) were used to detect the pathogenesis of ischemia-hypoxia injury. CPT-11 increased levels of tissue factor (TF) both in the blood and in intestines, and decreased the intestinal blood flow in mice. Interestingly, the elevation of TF in the blood displayed "double-peak," which was consistent with the intestinal mucosal "double-strike" injury trend. Intestinal microthrombus and mixed thrombus formation were detectable in chemotherapeutic enteritis. Furthermore, ozone therapy relieved chemotherapeutic enteritis in mice. Ozone inhibited TF expression induced by CPT-11 via activating AMPK/SOCS3, and effectively ameliorated the intestinal mucosal injury in mice. Moreover, ozone autotransfusion therapy effectively attenuated chemotherapeutic enteritis and the blood hypercoagulability in patients. For the first time, we proposed that TF-induced thrombotic intestinal ischemic injury is a core trigger pathological mechanism of chemotherapeutic enteritis, and provided a new treatment strategy, ozone therapy, to suppress TF expression and treat chemotherapeutic enteritis.

Dietary lipids fuel GPX4-restricted enteritis resembling Crohn's disease.

The increased incidence of inflammatory bowel disease (IBD) has become a global phenomenon that could be related to adoption of a Western life-style. Westernization of dietary habits is partly characterized by enrichment with the ω-6 polyunsaturated fatty acid (PUFA) arachidonic acid (AA), which entails risk for developing IBD. Glutathione peroxidase 4 (GPX4) protects against lipid peroxidation (LPO) and cell death termed ferroptosis. We report that small intestinal epithelial cells (IECs) in Crohn's disease (CD) exhibit impaired GPX4 activity and signs of LPO. PUFAs and specifically AA trigger a cytokine response of IECs which is restricted by GPX4. While GPX4 does not control AA metabolism, cytokine production is governed by similar mechanisms as ferroptosis. A PUFA-enriched Western diet triggers focal granuloma-like neutrophilic enteritis in mice that lack one allele of Gpx4 in IECs. Our study identifies dietary PUFAs as a trigger of GPX4-restricted mucosal inflammation phenocopying aspects of human CD.

Future therapies for eosinophilic gastrointestinal disorders.

OBJECTIVE: To review novel therapeutics in development for treatment of eosinophilic gastrointestinal disorders (EGIDs). DATA SOURCES: Clinical trial data (clinicaltrials.gov) and literature search on PubMed. STUDY SELECTIONS: Studies on treatment and clinical trials in EGIDs were included in this review. RESULTS: During the past decade, significant progress has been made in understanding disease mechanisms in EGIDs. As a result, a variety of novel therapeutics have been developed for treatment of these disorders. Several monoclonal antibodies against targets, including interleukin (IL) 4, IL-5, IL-13, integrins, and siglec-8, have shown promise in early trials. Novel formulations of corticosteroids are also in development. CONCLUSION: The field of EGID research has advanced rapidly, and disease-modifying therapeutics are closer to clinical application.

Sini San ameliorates duodenal mucosal barrier injury and low­grade inflammation via the CRF pathway in a rat model of functional dyspepsia.

The gut­brain interaction is associated with impaired duodenal mucosal integrity and low­grade inflammation, which have been proven to be important pathological mechanisms of functional dyspepsia (FD). Sini San (SNS) is a classical Chinese medicine used to treat FD, but its underlying mechanisms are poorly understood. The aim of the present study was to evaluate the effects of SNS on duodenal mucosal barrier injury and low­grade inflammation with FD, and to assess its potential molecular mechanisms on the brain­gut axis. FD rats were established using the iodoacetamide and tail­squeezed methods. The expression of corticotropin­releasing factor (CRF), CRF receptor 1 (CRF­R1) and CRF­R2, were determined by western blot analysis and/or immunohistochemistry (IHC). In addition, mast cell (MC) migration was assessed by IHC with an anti­tryptase antibody, and histamine concentration was quantified using ELISA. The mRNA expression levels of tryptase and protease­activated receptor 2 (PAR­2) were quantified using reverse transcription­quantitative PCR, and the protein expression levels of zona occludens protein 1 (ZO­1), junctional adhesion molecule 1 (JAM­1), ß­catenin and E­cadherin were determined via western blot analysis. It was demonstrated that the expression level of CRF was downregulated in the central nervous system and duodenum following SNS treatment, and that SNS modulated the expression of both CRF­R1 and CRF­R2. In addition, SNS suppressed MC infiltration and the activity of the tryptase/PAR­2 pathway in the duodenum. Furthermore, treatment with SNS restored the normal expression levels of ZO­1, JAM­1 and ß­catenin in FD rats. These findings suggested that the therapeutic effects of SNS on FD were achieved by restoring mucosal barrier integrity and suppressing low­grade inflammation in the duodenum, which was at least partially mediated via the CRF signaling pathway.

Animal Models of Undernutrition and Enteropathy as Tools for Assessment of Nutritional Intervention.

: Undernutrition is a major public health problem leading to 1 in 5 of all deaths in children under 5 years. Undernutrition leads to growth stunting and/or wasting and is often associated with environmental enteric dysfunction (EED). EED mechanisms leading to growth failure include intestinal hyperpermeability, villus blunting, malabsorption and gut inflammation. As non-invasive methods for investigating gut function in undernourished children are limited, pre-clinical models are relevant to elucidating the pathophysiological processes involved in undernutrition and EED, and to identifying novel therapeutic strategies. In many published models, undernutrition was induced using protein or micronutrient deficient diets, but these experimental models were not associated with EED. Enteropathy models mainly used gastrointestinal injury triggers. These models are presented in this review. We found only a few studies investigating the combination of undernutrition and enteropathy. This highlights the need for further developments to establish an experimental model reproducing the impact of undernutrition and enteropathy on growth, intestinal hyperpermeability and inflammation, that could be suitable for preclinical evaluation of innovative therapeutic intervention.

Corn gluten meal induces enteritis and decreases intestinal immunity and antioxidant capacity in turbot (Scophthalmus maximus) at high supplementation levels.

Corn gluten meal (CGM) is an important alternative protein source in aquafeed production. However, in turbot (Scophthalmus maximus), CGM could not be effectively utilized because of its low digestibility, the reason for which is still unclear. The purpose of the present study was to investigate and elucidate the cause for the poor utilization of CGM by turbot from the view of gut health. An 8-week feeding trial was conducted with turbot individuals (initial body weight 11.4 ± 0.2 g), which were fed with one of four isonitrogenous and isolipidic diets formulated to include 0%, 21.2%, 31.8%, and 42.6% CGM to progressively replace 0%, 33%, 50%, and 67% fish meal (FM) protein in a FM-based diet, respectively. The results showed that CGM caused dose-dependent decreases in (1) growth performance, nutrient digestibility, and feed utilization; (2) activities of brush-border membrane enzymes; (3) intestinal antioxidant indices of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase activities, and reduced glutathione level; (4) intestinal immune parameters of acid phosphatase activity, complement 3, complement 4, and IgM concentrations. Dose-dependent increases in the severity of the inflammation, with concomitant alterations on microvilli structure and increasing expression of inflammatory cytokine genes of Il-1ß, Il-8, and Tnf-α were observed but without a change in the intracellular junctions and the epithelial permeability established by the plasma diamine oxidase activity and D-lactate level examinations. In conclusion, the present work proved that CGM negatively affected the gut health of turbot by inducing enteritis and by decreasing intestinal immunity and antioxidant capacity, which could be one of the reasons for the reduced utilization of CGM by turbot.

N-acetylcysteine modulates lipopolysaccharide-induced intestinal dysfunction.

The gastrointestinal epithelium functions in nutrient absorption and pathogens barrier and its dysfunction directly affects livestock performance. N-Acetylcysteine (NAC) improves mucosal function, but its effects on intestinal functions at the molecular level remain unclear. Here, we performed gene expression profiling of the pig small intestine after dietary NAC treatment under LPS challenge and investigated the effects of NAC on intestinal epithelial cells in vitro. Dietary NAC supplementation under LPS challenge altered the small intestine expression of 959 genes related to immune response, inflammatory response, oxidation-reduction process, cytokine-cytokine receptor interaction, and the cytokine-mediated signalling, Toll-like receptor signalling pathway, Jak-STAT signalling pathway, and TNF signalling pathway. We then analysed the expression patterns of the top 10 altered genes, and found that NAC markedly stimulated HMGCS3 and LDHC expression in IPEC-J2 cells. In vitro, NAC pre-treatment significantly reduced TNF-α and NF-κB, TNF-α, IFN-γ, and IL-6 expression in LPS-induced IPEC-J2 cells. NAC treatment also significantly reduced oxidative stress in LPS-induced IPEC-J2 cells and alleviated intestinal barrier function and wound healing. Thus, NAC as a feed additive can enhance livestock intestinal health by modulating intestinal inflammation, permeability, and wound healing under LPS-induced dysfunction, improving our molecular understanding of the effects of NAC on the intestine.

A combination of NMR and liquid chromatography to characterize the protective effects of Rhus tripartita extracts on ethanol-induced toxicity and inflammation on intestinal cells.

Consumption of ethanol may have severe effects on human organs and tissues and lead to acute and chronic inflammation of internal organs. The present study aims at investigating the potential protective effects of three different extracts prepared from the leaves, root, and stem of the sumac, Rhus tripartita, against ethanol-induced toxicity and inflammation using intestinal cells as a cell culture system, in vitro model of the intestinal mucosa. The results showed an induction of cytotoxicity by ethanol, which was partially reversed by co-administration of the plant extracts. As part of investigating the cellular response and the mechanism of toxicity, the role of reduced thiols and glutathione-S-transferases were assessed. In addition, intestinal cells were artificially imposed to an inflammation state and the anti-inflammatory effect of the extracts was estimated by determination of interleukin-8. Finally, a detailed characterization of the contents of the three plant extracts by high resolution Nuclear Magnetic Resonance (NMR) spectroscopy and mass spectrometry revealed significant differences in their chemical compositions.

The American cockroach peptide periplanetasin-4 inhibits Clostridium difficile toxin A-induced cell toxicities and inflammatory responses in the mouse gut.

Many reports have shown that crude extracts of the American cockroach have therapeutic effects on inflammation. In a previous study, our research group showed that an antimicrobial peptide (Periplanetasin-2) derived from the American cockroach via de novo transcriptome analysis inhibited apoptosis of human colonocytes and inflammatory responses of the mouse gut caused by Clostridium difficile toxin A. Here, we examined whether Periplanetasin-4 (Peri-4), another antimicrobial peptide identified via de novo transcriptome analysis of the American cockroach, could also inhibit the various toxicities induced by C. difficile toxin A. We found that Peri-4 significantly reduced the cell viability loss and cell apoptosis caused by toxin A in vitro. Peri-4 also ameliorated the severe inflammatory responses seen in the toxin A-induced mouse enteritis model, rescuing the villus disruption and interleukin-6 production induced by luminal injection of toxin A into the mouse gut. Mechanistically, we found that Peri-4 could reduce toxin A-induced reactive oxygen species production to inhibit the activations of p38MAPK and p21Cip1/Waf1 , which are critical for the cell damages induced by toxin A. These results collectively suggest that the Peri-4 may be a potential therapeutic agent for treating toxin A-induced pseudomembranous colitis. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.

Emu Oil Combined with Lyprinol™ Reduces Small Intestinal Damage in a Rat Model of Chemotherapy-Induced Mucositis.

Chemotherapy-induced mucositis is characterized by inflammation and ulcerating lesions lining the alimentary tract. Emu Oil and Lyprinol™ have independently demonstrated their therapeutic potential in intestinal inflammatory disorders, including mucositis. We investigated Emu Oil and Lyprinol™ in combination for their further potential to alleviate chemotherapy-induced mucositis in rats. Rats were gavaged with (1 ml) water, Olive Oil, Emu Oil + Olive Oil, Lyprinol™ + Olive Oil or Emu Oil + Lyprinol™ from Days 0 to 7, injected with saline (control) or 5-Fluorouracil (5-FU) on Day 5 and euthanized on Day 8. Myeloperoxidase (MPO) activity (indicative of acute inflammation), histological severity scores, and intestinal architecture were quantified. Myeloperoxidase activity was significantly increased in the jejunum and ileum following 5-FU, compared to saline controls. Both Olive Oil and Emu Oil + Lyprinol™ significantly reduced jejunal MPO levels (1.8-fold and 1.7-fold, respectively), whereas only Emu Oil + Lyprinol™ significantly decreased ileal MPO levels, relative to 5-FU controls. All oil treatments decreased histological severity scores in the jejunum and ileum, and normalized crypt depth in the mid small intestine, relative to 5-FU controls. Emu Oil combined with Lyprinol™ partially reduced acute small intestinal inflammation. Isolating bioactive constituents of these naturally sourced oils could provide a more targeted strategy to protect against intestinal mucositis.

Lactoferrin Decreases the Intestinal Inflammation Triggered by a Soybean Meal-Based Diet in Zebrafish.

Intestinal inflammation is a harmful condition in fish that can be triggered by the ingestion of soybean meal. Due to the positive costs-benefits ratio of including soybean meal in farmed fish diets, identifying additives with intestinal anti-inflammatory effects could contribute to solving the issues caused by this plant protein. This study evaluated the effect of incorporating lactoferrin (LF) into a soybean meal-based diet on intestinal inflammation in zebrafish. Larvae were fed with diets containing 50% soybean meal (50SBM) or 50SBM supplemented with LF to 0.5, 1, 1.5 g/kg (50SBM+LF0.5; 50SBM+LF1.0; 50SBM+LF1.5). The 50SBM+LF1.5 diet was the most efficient and larvae had a reduced number of neutrophils in the intestine compared with 50SBM larvae and an indistinguishable number compared with control larvae. Likewise, the transcription of genes involved in neutrophil migration and intestinal mucosal barrier functions (mmp9, muc2.2, and ß-def-1) were increased in 50SBM larvae but were normally expressed in 50SBM+LF1.5 larvae. To determine the influence of intestinal inflammation on the general immune response, larvae were challenged with Edwardsiella tarda. Larvae with intestinal inflammation had increased mortality rate compared to control larvae. Importantly, 50SBM+LF1.5 larvae had a mortality rate lower than control larvae. These results demonstrate that LF displays a dual effect in zebrafish, acting as an intestinal anti-inflammatory agent and improving performance against bacterial infection.

Dynamics of intestinal metabolites and morphology in response to necrotic enteritis challenge in broiler chickens.

Despite the relatively small contribution to metabolizable energy that volatile fatty acids (VFAs) provide in chickens, these organic acids have been reported to play beneficial roles in the gastrointestinal tract (GIT) of birds, for example, inhibition of the growth of some pathogenic bacteria. However, information regarding the dynamics of these metabolites in the GIT of chickens is still scarce, especially under disease conditions such as necrotic enteritis (NE). Here, we investigated the dynamics of VFAs and lactic acid, and intestinal morphology in response to NE predisposing factors, that is, excessive dietary fishmeal and Eimeria inoculation, and causative agent Clostridium perfringens producing NetB toxin. The experiment was designed in a 2 × 2 × 2 factorial arrangement of treatments with or without: fishmeal feeding, Eimeria inoculation and C. perfringens challenge. The results showed that these factors significantly influenced composition and concentration of VFAs and lactic acids, pH and histomorphometry in one way or another. These changes may be important for the onset of NE or only the synergetic responses to micro environmental stress. Eimeria appeared to be more important than fishmeal in predisposing birds to NE, thus the application of Eimeria in NE challenge provides more consistent success in inducing the disease. The metabolic responses to various adverse factors such as excessive dietary fishmeal and Eimeria infection are complex. Thus, intensive efforts are required to better understand NE so as to achieve the control of the disease in the absence of antibiotics.

Capsaicin-induced satiety is associated with gastrointestinal distress but not with the release of satiety hormones.

BACKGROUND: Capsaicin, which is the major pungent principle in chili peppers, is able to induce satiety and reduce caloric intake. The exact mechanism behind this satiating effect is still unknown. We hypothesized that capsaicin induces satiety through the release of gastrointestinal peptides, such as glucagon-like peptide-1 (GLP-1) and peptide YY (PYY), from enteroendocrine cells in the small intestine. OBJECTIVE: We investigate the effects of an intraduodenal capsaicin infusion (1.5 mg pure capsaicin) in healthy volunteers on hunger, satiety, and gastrointestinal symptoms and the release of GLP-1 and PYY. DESIGN: Thirteen participants (7 women) [mean ± SEM age: 21.5 ± 0.6 y; body mass index (in kg/m(2)): 22.8 ± 0.6] participated in this single-blind, randomized, placebo-controlled crossover study with 2 different treatments. During test days, an intraduodenal infusion of either capsaicin or a placebo (physiologic saline) was performed with the use of a nasoduodenal catheter over a period of 30 min. Visual analog scale scores were used to measure hunger, satiety, and gastrointestinal symptoms. Blood samples were drawn at regular intervals for GLP-1 and PYY. Gallbladder volumes were measured with the use of real-time ultrasonography. RESULTS: The intraduodenal capsaicin infusion significantly increased satiety (P-treatment effect < 0.05) but also resulted in an increase in the gastrointestinal symptoms pain (P-treatment × time interaction < 0.0005), burning sensation (P-treatment × time interaction < 0.0001), nausea (P-treatment × time interaction < 0.05), and bloating (P-treatment × time interaction < 0.001) compared with the effects of the placebo infusion. Satiety scores had a positive correlation with all gastrointestinal symptoms. No differences in GLP-1 and PYY concentrations and gallbladder volumes were observed after the capsaicin infusion compared with after the placebo infusion. CONCLUSIONS: An intraduodenal infusion of capsaicin significantly increases satiety but does not affect plasma concentrations of GLP-1 and PYY. Rather, the effect on satiety seems related to gastrointestinal stress as shown by the associations with pain, burning sensation, nausea, and bloating scores. This trial was registered at clinicaltrials.gov as NCT01667523.

Heterogeneous Nuclear Ribonucleoprotein A1 Improves the Intestinal Injury by Regulating Apoptosis Through Trefoil Factor 2 in Mice with Anti-CD3-induced Enteritis.

BACKGROUND: The role of hnRNP A1 in the onset of intestinal inflammation remains unclear. This study investigated the function of hnRNP A1 in mice enteritis models. METHODS: C57Bl6/J mice were intraperitoneally injected with anti-CD3 antibodies to develop enteritis. In the DSS-induced colitis group, the mice were allowed free access to 3% DSS solution in their drinking water for 5 days. 3H-mannitol flux and complementary DNA array tests were used to assess the intestinal barrier function and messenger RNA (mRNA) expression, respectively. Real-time PCR was performed after immunoprecipitation with anti-hnRNP antibodies to determine the specific mRNA binding of hnRNP A1. RESULTS: The hnRNP A1 expression was increased in the intestine of the mouse at 24 hours after treatment with anti-CD3 antibodies and 5 days after starting DSS administration. Small interfering RNA (siRNA) against hnRNP A1 exacerbated the intestinal injuries in both models. According to the microarray analysis, trefoil factor 2 (TFF2) was identified as a candidate molecule targeted by hnRNP A1 in the anti-CD3 antibody-induced enteritis group. Moreover, the binding between hnRNP A1 and TFF2 mRNA significantly increased in the enteritis mice, and the administration of siRNA against either hnRNP A1 or TFF2 exacerbated the degree of intestinal injury. In the DSS-induced colitis group, treatment with the siRNA of hnRNP A1 worsened the intestinal injury, while the expression of TFF3 did not change. CONCLUSIONS: hnRNP A1 improves intestinal injury in anti-CD3 antibody-induced enteritis mice through the upregulation of TFF2, which regulates apoptosis and enhances epithelial restoration, whereas this molecule ameliorates DSS-induced colitis through a different pathway.

Maternal high-zinc diet attenuates intestinal inflammation by reducing DNA methylation and elevating H3K9 acetylation in the A20 promoter of offspring chicks.

A20 is an anti-inflammatory protein that suppresses ubiquitin-dependent nuclear factor κB (NF-κB) signaling, which can be regulated by the microelement zinc (Zn). In mammals, Zn deficiency contributes to a decrease in A20 abundance, which impairs the gut mucosa barrier. However, it is unclear whether the epigenetic reprogramming of the A20 promoter is involved in enhanced Zn-induced intestinal immunity, especially in avian species. Herein, we show that maternal organic Zn exposure resulted in significantly improved intestinal morphological characteristics, increased mucin 2 (MUC2) abundance and secretory IgA (sIgA) production in progeny jejunums. Maternal and offspring Zn supplementation partially alleviated Zn-deficiency-induced inflammatory response, accompanied by repression of NF-κB signaling. Additionally, we observed DNA hypomethylation and histone H3 at lysine 9 (H3K9) hyperacetylation at the A20 promoter region and subsequent activated A20 expression in Zn-supplemented hens compared with control. Notably, maternal dietary organic Zn exposure exhibited greater attenuation of gut impairment, along with increased MUC2 expression and sIgA level, and decreased the abundance of TNF-α and A20 relative to the inorganic-Zn group. Furthermore, enhanced acetylated H3K9 and A20 transcription at day 14 was found in the offspring adequate dietary Zn group. Thus, A20 may be a novel inflammatory-suppressed factor of chick gut that is persistently promoted by dietary Zn supplementation via epigenetic modifications at A20 promoter.

TU-100 (Daikenchuto) and ginger ameliorate anti-CD3 antibody induced T cell-mediated murine enteritis: microbe-independent effects involving Akt and NF-κB suppression.

The Japanese traditional medicine daikenchuto (TU-100) has anti-inflammatory activities, but the mechanisms remain incompletely understood. TU-100 includes ginger, ginseng, and Japanese pepper, each component possessing bioactive properties. The effects of TU-100 and individual components were investigated in a model of intestinal T lymphocyte activation using anti-CD3 antibody. To determine contribution of intestinal bacteria, specific pathogen free (SPF) and germ free (GF) mice were used. TU-100 or its components were delivered by diet or by gavage. Anti-CD3 antibody increased jejunal accumulation of fluid, increased TNFα, and induced intestinal epithelial apoptosis in both SPF and GF mice, which was blocked by either TU-100 or ginger, but not by ginseng or Japanese pepper. TU-100 and ginger also blocked anti-CD3-stimulated Akt and NF-κB activation. A co-culture system of colonic Caco2BBE and Jurkat-1 cells was used to examine T-lymphocyte/epithelial cells interactions. Jurkat-1 cells were stimulated with anti-CD3 to produce TNFα that activates epithelial cell NF-κB. TU-100 and ginger blocked anti-CD3 antibody activation of Akt in Jurkat cells, decreasing their TNFα production. Additionally, TU-100 and ginger alone blocked direct TNFα stimulation of Caco2BBE cells and decreased activation of caspase-3 and polyADP ribose. The present studies demonstrate a new anti-inflammatory action of TU-100 that is microbe-independent and due to its ginger component.

Long-term cysteine fortification impacts cysteine/glutathione homeostasis and food intake in ageing rats.

PURPOSE: Healthy ageing is associated with higher levels of glutathione. The study aimed to determine whether long-term dietary fortification with cysteine increases cysteine and glutathione pools, thus alleviating age-associated low-grade inflammation and resulting in global physiological benefits. METHODS: The effect of a 14-week dietary fortification with cysteine was studied in non-inflamed (NI, healthy at baseline) and in spontaneously age-related low-grade inflamed (LGI, prefrail at baseline) 21-month-old rats. Fifty-seven NI rats and 14 LGI rats received cysteine-supplemented diet (4.0 g/kg of free cysteine added to the standard diet containing 2.8 g/kg cysteine). Fifty-six NI rats and 16 LGI rats received a control alanine-supplemented diet. RESULTS: Cysteine fortification in NI rats increased free cysteine (P < 0.0001) and glutathione (P < 0.03) in the liver and the small intestine. In LGI rats, cysteine fortification increased total non-protein cysteine (P < 0.0007) and free cysteine (P < 0.03) in plasma, and free cysteine (P < 0.02) and glutathione (P < 0.01) in liver. Food intake decreased over time in alanine-fed rats (r² = 0.73, P = 0.0002), whereas it was constant in cysteine-fed rats (r² = 0.02, P = 0.68). Cysteine fortification did not affect inflammatory markers, mortality, body weight loss, or tissue masses. CONCLUSION: Doubling the dietary intake of cysteine in old rats increased cysteine and glutathione pools in selected tissues. Additionally, it alleviated the age-related decline in food intake. Further validation of these effects in the elderly population suffering from age-related anorexia would suggest a useful therapeutic approach to the problem.

TNF-alpha modulates iNOS expression in an experimental rat model of indomethacin-induced jejunoileitis.

Multiple mucosal immune factors, such as TNF-alpha and IL-1beta, are thought to be key mediators involved in inflammatory bowel disease. We evaluated the role of the pro-inflammatory cytokine TNF-alpha on nitric oxide synthase (NOS) expression in indomethacin-induced jejunoileitis in rats. Jejunoileitis was induced in rats with subcutaneous injections of indomethacin (7.5 mg/kg) 24 h apart for two consecutive days, and animals were randomized into four groups. Group 1 received only indomethacin. Group 2 was treated with a daily dose of phosphodiesterase (PDE) inhibitor (theophylline or pentoxifylline) by oral gavage for 2 days before and 4 days after indomethacin. Group 3 received a single dose of anti-TNF-alpha monoclonal antibody (TNF-Ab, IP) 30 min before indomethacin. Group 4 was treated with 1 h hyperbaric oxygenation (HBO(2)) for 5 days after indomethacin. Rats were sacrificed at 12 h or 4 days after final indomethacin injection. PDE inhibitor, TNF-Ab, or HBO(2) treatment significantly decreased indomethacin-induced ulceration, myeloperoxidase activity, and disease activity index. Although indomethacin significantly increased serum TNF-alpha and nitrate/nitrite (NOx) concentrations above control values at 12 h, inducible NOS (iNOS) expression was detected only at day 4. Serum IL-1beta levels did not change at 12 h but increased 4-fold after 4 days. Indomethacin had no effect on constitutive NOS. Treatment with PDE inhibitor, TNF-Ab, or HBO(2) significantly reduced serum/tissue TNF-alpha, IL-1beta, NOx, and iNOS expression. Our data show TNF-alpha plays an early pro-inflammatory role in indomethacin-induced jejunoileitis. Additionally, down-regulation of NOx by PDE inhibitors, TNF-Ab, or HBO(2) suggests that TNF-alpha modulates iNOS expression.