Preventive and therapeutic effects of blueberry (Vaccinium corymbosum) extract against DSS-induced ulcerative colitis by regulation of antioxidant and inflammatory mediators

An overview on the cellular mechanisms of anthocyanins in maintaining intestinal integrity and function

Structural and functional changes of the intestinal barrier, as a consequence of a number of (epi)genetic and environmental causes, have a main role in penetrations of pathogens and toxic agents, and lead to the development of inflammation-related pathological conditions, not only at the level of the GI tract but also in other extra-digestive tissues and organs. Anthocyanins (ACNs), a subclass of polyphenols belonging to the flavonoid group, are well known for their health-promoting properties and are widely distributed in the human diet. There is large evidence about the correlation between the human intake of ACN-rich products and a reduction of intestinal inflammation and dysfunction. Our review describes the more recent advances in the knowledge of cellular and molecular mechanisms through which ACNs can modulate the main mechanisms involved in intestinal dysfunction and inflammation, in particular the inhibition of the NF-κB, JNK, MAPK, STAT3, and TLR4 proinflammatory pathways, the upregulation of the Nrf2 transcription factor and the expression of tight junction proteins and mucins.

Antagomir of miR-31-5p modulates macrophage polarization via the AMPK/SIRT1/NLRP3 signaling pathway to protect against DSS-induced colitis in mice

Macrophage-driven immune dysfunction of the intestinal mucosa is involved in the pathophysiology of ulcerative colitis (UC). Emerging evidence indicates that there is an elevation in miR-31-5p levels in UC, which is accompanied by a downregulation of adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) expression. Nevertheless, the precise influence of miR-31-5p on macrophage polarization and the integrity of the intestinal epithelial barrier in UC remains to be fully elucidated. This study explored the role of miR-31-5p and AMPK in UC through a bioinformatics investigation. It investigated the potential of miR-31-5p antagomir to shift macrophages from pro-inflammatory M1 phenotype to anti-inflammatory M2 phenotype and enhance the intestinal mucosal barrier in DSS-induced UC mice. Additionally, RAW264.7 cells stimulated with LPS were employed to confirm the reversal of miR-31-5p antagomir's therapeutic effect under AMPK inhibition. The findings demonstrated that miR-31-5p antagomir penetrated colonic tissues and ameliorated DSS-induced experimental colitis. Transformation of spleen and mesenteric lymph node macrophages from M1 to M2 type was seen in the DSS+miR-31-5p antagomir group. AMPK/Sirt1 expression increased while NLRP3 expression decreased. Expression of M2-related genes and proteins was enhanced and that of the M1 phenotype suppressed. Tight junction proteins, ZO-1 and occludin, were increased. The therapeutic effects of miR-31-5p antagomir transfection into RAW264.7 cells were repressed when AMPK expression was inhibited. Therefore, our results suggest that suppression of miR-31-5p expression transformed macrophages from M1 to M2, ameliorated inflammation and repaired the intestinal epithelium to alleviate DSS-induced colitis. AMPK/Sirt1/NLRP3 was involved.

Citrate-coated silver nanoparticles loaded with agomelatine provide neuronal therapy in acute cerebral ischemia/reperfusion of rats by inhibiting the oxidative stress, endoplasmic reticulum stress, and P2X7 receptor-mediated inflammasome

Cerebral ischemia and reperfusion are related to various situations like injuries after various traumas, oxidative stress, increased calcium ion, capillary hypoperfusion, microvascular hyperpermeability, leukocyte infiltration, and blood-brain barrier disruption. An antidepressant Agomelatine which is a melatonin receptor (MT1/MT2) agonist and serotonin receptor (5-HT2C) antagonist has been reported by studies to have antioxidant and anti-inflammatory effects. In our study, we aimed to detect the effects of citrate-coated silver nanoparticle-loaded agomelatine application on neurodegeneration, endoplasmic reticulum stress, autophagic and apoptotic cell death, inflammation, and P2X7R expression in the cerebral ischemia-reperfusion model to facilitate the passage of blood-brain barrier. Forty two Sprague-Dawley rats in total were divided into six equal groups (n:7) and applications were performed. Acute cerebral injury in the ischemia-reperfusion model was created 2 h after internal carotid artery ligation in rats and then at the 2nd hour of reperfusion citrate-coated silver nanoparticles loaded with Agomelatine were applied. Twenty four hours later, neurologic analysis on animals in experimental groups was performed, animals were decapitated and GSH, GPx, SOD, CAT, MDA, IL-1β, and TNF-α parameters were examined after taking blood and the cerebral tissue samples. As a result, it was determined that ischemia-reperfusion caused endoplasmic reticulum stress in the cerebral tissues and thus caused cellular injury.

Curcumin Co-Encapsulation Potentiates Anti-Arthritic Efficacy of Meloxicam Biodegradable Nanoparticles in Adjuvant-Induced Arthritis Animal Model

This study aimed to evaluate the anti-arthritic activity of curcumin and meloxicam co-loaded PLGA nanoparticles in adjuvant-induced arthritic rats. PLGA nanoparticles encapsulating curcumin (nCur) and meloxicam (nMlx) alone and in combination (nCur/Mlx) were used to characterize zeta size and potential, polydispersity index, encapsulation efficiency (%), compound-polymer interactions (FT-IR analysis), and surface morphology (SEM imaging). In vivo, Complete Freund's adjuvant-induced arthritic rats were intraperitoneally (i.p.) administered with curcumin, meloxicam, curcumin plus meloxicam, nCur, nMlx, and nCur/Mlx for 28 consecutive days. Results showed that nCur, nMlx, and nCur/Mlx significantly (p ≤ 0.05) reduced paw swelling and arthritic score, restored body weight and the immune organ index (thymus and spleen), as well as attenuated serum inflammatory markers (RF, CRP, and PGE2) and oxidative stress parameters (MDA, SOD, and CAT) in adjuvant-induced arthritic rats compared to free compounds. In addition, mono- and dual-compound-loaded nanoparticles significantly (p ≤ 0.05) down-regulated pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6), up-regulated anti-inflammatory cytokines (IL-4, IL-10, and IFN-γ), and modulated OPG and RANKL expressions in paw tissue. The aforementioned results were further confirmed through radiological and histopathological examinations. Furthermore, the anti-arthritic effect of nCur/Mlx was notably (p ≤ 0.05) enhanced compared to nCur or nMlx alone. In conclusion, the co-nanoencapsulation of curcumin could potentiate the anti-arthritic activity of meloxicam and could provide a novel therapeutic approach for the formulation of nanocarrier pharmaceutical products for the management of arthritis.

Direct Polyphenol Attachment on the Surfaces of Magnetite Nanoparticles, Using Vitis vinifera, Vaccinium corymbosum, or Punica granatum

This study presents an alternative approach to directly synthesizing magnetite nanoparticles (MNPs) in the presence of Vitis vinifera, Vaccinium corymbosum, and Punica granatum derived from natural sources (grapes, blueberries, and pomegranates, respectively). A modified co-precipitation method that combines phytochemical techniques was developed to produce semispherical MNPs that range in size from 7.7 to 8.8 nm and are coated with a ~1.5 nm thick layer of polyphenols. The observed structure, composition, and surface properties of the MNPs@polyphenols demonstrated the dual functionality of the phenolic groups as both reducing agents and capping molecules that are bonding with Fe ions on the surfaces of the MNPs via -OH groups. Magnetic force microscopy images revealed the uniaxial orientation of single magnetic domains (SMDs) associated with the inverse spinel structure of the magnetite (Fe3O4). The samples' inductive heating (H0 = 28.9 kA/m, f = 764 kHz), measured via the specific loss power (SLP) of the samples, yielded values of up to 187.2 W/g and showed the influence of the average particle size. A cell viability assessment was conducted via the MTT and NRu tests to estimate the metabolic and lysosomal activities of the MNPs@polyphenols in K562 (chronic myelogenous leukemia, ATCC) cells.

Oxidative stress, hormones, and effects of natural antioxidants on intestinal inflammation in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic, relapsing gastrointestinal (GI) disorder characterized by intestinal inflammation. The etiology of IBD is multifactorial and results from a complex interplay between mucosal immunity, environmental factors, and host genetics. Future therapeutics for GI disorders, including IBD, that are driven by oxidative stress require a greater understanding of the cellular and molecular mechanisms mediated by reactive oxygen species (ROS). In the GI tract, oxidative stressors include infections and pro-inflammatory responses, which boost ROS generation by promoting the production of pro-inflammatory cytokines. Nuclear factor kappa B (NF-κB) and nuclear factor erythroid 2-related factor 2 (Nrf2) represent two important signaling pathways in intestinal immune cells that regulate numerous physiological processes, including anti-inflammatory and antioxidant activities. Natural antioxidant compounds exhibit ROS scavenging and increase antioxidant defense capacity to inhibit pro-oxidative enzymes, which may be useful in IBD treatment. In this review, we discuss various polyphenolic substances (such as resveratrol, curcumin, quercetin, green tea flavonoids, caffeic acid phenethyl ester, luteolin, xanthohumol, genistein, alpinetin, proanthocyanidins, anthocyanins, silymarin), phenolic compounds including thymol, alkaloids such as berberine, storage polysaccharides such as tamarind xyloglucan, and other phytochemicals represented by isothiocyanate sulforaphane and food/spices (such as ginger, flaxseed oil), as well as antioxidant hormones like melatonin that target cellular signaling pathways to reduce intestinal inflammation occurring with IBD.

Dealcoholized muscadine wine was partially effective in preventing and treating dextran sulfate sodium-induced colitis and restoring gut dysbiosis in mice

Muscadine wine has a unique polyphenol profile consisting of anthocyanins, ellagic acids, and flavonols. This study aims to compare the prevention, treatment, and combined activity (P + T) of dealcoholized muscadine wine (DMW) on DSS-induced colitis in mice and its impact on the gut microbiome. Male C57BL/6 mice in the healthy and colitis group received an AIN-93M diet for 28 days. In the prevention, treatment, and P + T (prevention + treatment) groups, mice received an AIN-93M diet containing 2.79% (v/w) DMW on days 1-14, 15-28, and 1-28, respectively. Except for mice in the healthy group, all mice were given water with 2.5% (w/v) DSS on days 8-14 to induce colitis. DMW in all three receiving groups reduced myeloperoxidase activity, histology scores, and phosphorylation of Iκb-α in the colon. Colon shortening, serum IL-6, and colonic mRNA of TNF-α were blunted only in the P + T group. Gut permeability was reduced in the treatment and P + T groups. DMW in P + T group showed higher activity to increase microbiome evenness, modulate β-diversity, elevate the cecal content of SCFAs, and enrich SCFA-producing bacteria, including Lactobacillaceae, Lachnospiraceae, Ruminococcaceae, and Peptococcaceae. This was accompanied by a decrease in pathogenic Burkholderiaceae in mice. This study suggests that muscadine wine has partial preventive and therapeutic effects against inflammatory bowel disease. The combination of prevention and treatment using DMW showed better activities than either prevention or treatment.

Blueberries Improve Abdominal Symptoms, Well-Being and Functioning in Patients with Functional Gastrointestinal Disorders

Blueberries beneficially modulate physiologic mechanisms relevant to the pathogenesis of functional gastrointestinal disorders (FGID). Forty-three patients with FGID received freeze-dried blueberries (equivalent to 180 g fresh blueberries) or sugar and energy-matched placebo in a double-blind, randomized, cross-over study. After 6 weeks of treatment, the differences in Gastrointestinal Clinical Rating Scale (GSRS) scores and abdominal symptom relief were compared as primary outcome measures. The quality of life and life functioning ratings (OQ45.2 questionnaire), Bristol stool scales, and fructose breath test results constituted secondary outcome measures. Blueberry treatment resulted in more patients with relevant abdominal symptom relief compared to placebo (53% vs. 30%, p = 0.03). Total and pain GSRS scores improved insignificantly (mean treatment differences [95% CI]: -3.4 [-7.4 to 0.6] (p = 0.09) and -1.0 [-2.2 to 0.1] (p = 0.08), respectively). OQ45.2 scores improved during blueberry treatment compared to placebo (treatment difference -3.2 [95% CI: -5.6 to -0], p = 0.01). Treatment effect differences for the further measures did not reach statistical significance. Blueberries relieved abdominal symptoms and improved general markers of well-being, quality of life, and life functioning more than placebo in patients with FGID. Consequently, the polyphenol and fiber components of blueberries exert broad beneficial effects separate from the sugars present in both treatments.

Targeting the aryl hydrocarbon receptor by gut phenolic metabolites: A strategy towards gut inflammation

The Aryl Hydrocarbon Receptor (AHR) is a ligand-dependent transcription factor able to control complex transcriptional processes in several cell types, which has been correlated with various diseases, including inflammatory bowel diseases (IBD). Numerous studies have described different compounds as ligands of this receptor, like xenobiotics, natural compounds, and several host-derived metabolites. Dietary (poly)phenols have been studied regarding their pleiotropic activities (e.g., neuroprotective and anti-inflammatory), but their AHR modulatory capabilities have also been considered. However, dietary (poly)phenols are submitted to extensive metabolism in the gut (e.g., gut microbiota). Thus, the resulting gut phenolic metabolites could be key players modulating AHR since they are the ones that reach the cells and may exert effects on the AHR throughout the gut and other organs. This review aims at a comprehensive search for the most abundant gut phenolic metabolites detected and quantified in humans to understand how many have been described as AHR modulators and what could be their impact on inflammatory gut processes. Even though several phenolic compounds have been studied regarding their anti-inflammatory capacities, only 1 gut phenolic metabolite, described as AHR modulator, has been evaluated on intestinal inflammatory models. Searching for AHR ligands could be a novel strategy against IBD.

Platycodon grandiflorus polysaccharide regulates colonic immunity through mesenteric lymphatic circulation to attenuate ulcerative colitis

Platycodon grandiflorus polysaccharide (PGP) is one of the main components of P. grandiflorus, but the mechanism of its anti-inflammatory effect has not been fully elucidated. The aim of this study was to evaluate the therapeutic effect of PGP on mice with dextran sodium sulfate (DSS)-induced ulcerative colitis (UC) and explore the underlying mechanisms. The results showed that PGP treatment inhibited the weight loss of DSS-induced UC mice, increased colon length, and reduced DAI, spleen index, and pathological damage within the colon. PGP also reduced the levels of pro-inflammatory cytokines and inhibited the enhancement of oxidative stress and MPO activity. Meanwhile, PGP restored the levels of Th1, Th2, Th17, and Treg cell-related cytokines and transcription factors in the colon to regulate colonic immunity. Further studies revealed that PGP regulated the balance of colonic immune cells through mesenteric lymphatic circulation. Taken together, PGP exerts anti-inflammatory and anti-oxidant effect and regulates colonic immunity to attenuate DSS-induced UC through mesenteric lymphatic circulation.

Leaky Gut and the Ingredients That Help Treat It: A Review

The human body is in daily contact with potentially toxic and infectious substances in the gastrointestinal tract (GIT). The GIT has the most significant load of antigens. The GIT can protect the intestinal integrity by allowing the passage of beneficial agents and blocking the path of harmful substances. Under normal conditions, a healthy intestinal barrier prevents toxic elements from entering the blood stream. However, factors such as stress, an unhealthy diet, excessive alcohol, antibiotics, and drug consumption can compromise the composition of the intestinal microbiota and the homeostasis of the intestinal barrier function of the intestine, leading to increased intestinal permeability. Intestinal hyperpermeability can allow the entry of harmful agents through the junctions of the intestinal epithelium, which pass into the bloodstream and affect various organs and systems. Thus, leaky gut syndrome and intestinal barrier dysfunction are associated with intestinal diseases, such as inflammatory bowel disease and irritable bowel syndrome, as well as extra-intestinal diseases, including heart diseases, obesity, type 1 diabetes mellitus, and celiac disease. Given the relationship between intestinal permeability and numerous conditions, it is convenient to seek an excellent strategy to avoid or reduce the increase in intestinal permeability. The impact of dietary nutrients on barrier function can be crucial for designing new strategies for patients with the pathogenesis of leaky gut-related diseases associated with epithelial barrier dysfunctions. In this review article, the role of functional ingredients is suggested as mediators of leaky gut-related disorders.

Jatrorrhizine Alleviates DSS-Induced Ulcerative Colitis by Regulating the Intestinal Barrier Function and Inhibiting TLR4/MyD88/NF-κB Signaling Pathway

Background

Ulcerative colitis (UC), a kind of autoimmune disease with unknown etiology, has been troubling human physical and mental health. Jatrorrhizine (Jat) is a natural isoquinoline alkaloid isolated from Coptis Chinensis, which has been proved to have antibacterial, anti-inflammatory, and antitumor effects.

Purpose

The purpose is to explore the therapeutic effect of Jat on DSS-induced UC and the mechanism of action. Study Design. The UC mice model was induced by 3% DSS in drinking water. The mice were orally administered with Jat (40, 80, 160 mg/kg) for 10 days.

Methods

The changes in body weight, colon length, spleen wet weight index, disease activity index (DAI), colonic histopathology, and inflammatory factors of serum and colon tissue were analyzed to evaluate the severity of colitis mice. The colon mucus secretion capacity was analyzed by Alcian blue periodic acid Schiff (AB-PAS) staining. Furthermore, protein expressions such as TLR4, MyD88, p–NF–κB-p65, NF-κB-p65, COX-2, ZO-1, and Occludin were detected to elucidate the molecular mechanism of Jat on DSS-induced colitis model.

Results

The results showed that Jat could significantly alleviate the symptoms, colon shortening, spleen index, and histological damage and restore the body weight in DSS-induced colitis mice. Jat also suppressed the levels of inflammatory cytokines and upregulated the levels of anti-inflammatory cytokines. In addition, Jat repaired the intestinal barrier function by upregulating the level of colonic tight junction (TJ) proteins and enhancing the secretion of mucin produced by goblet cells. Furthermore, Jat could significantly suppress the expression of TLR4, MyD88, p–NF–κB-p65/NF-κB-p65, and COX-2 in colon tissue.

Conclusion

The results suggested that Jat plays a protective role in DSS-induced colitis by regulating the intestinal barrier function and inhibiting the TLR4/MyD88/NF-κB signaling pathway. This study, for the first time, demonstrates the therapeutic and protective effects of Jat on UC.

Anti-Colitic Effect of an Exopolysaccharide Fraction from Pediococcus pentosaceus KFT-18 on Dextran Sulfate Sodium-Induced Colitis through Suppression of Inflammatory Mediators

We previously reported the immunostimulatory effect of an exopolysaccharide fraction from Pediococcus pentosaceus KFT18 (PE-EPS), a lactic acid bacterium, in macrophages and primary splenocytes, as well as in cyclophosphamide-induced immunosuppressed mice. In this study, the anti-colitic activity of PE-EPS was investigated in a dextran sulfate sodium (DSS)-induced colitis animal model. PE-EPS relieved DSS-induced colitis symptoms, such as stool blood, decreased colon length, crypt disruption, and mucus layer edema. Regarding the molecular mechanism, PE-EPS reduced the enhanced expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and pro-inflammatory cytokines (TNF-α, IL-6, and IL-1) in the colon tissue of colitis-induced mice. Additionally, PE-EPS protected against DSS-induced phosphorylation of p65 and signal transducer and activator of transcription 1 (STAT1). These findings suggested that the exopolysaccharide fraction from Ped. pentosaceus KFT18 can be used to treat inflammatory bowel disease by alleviating colonic inflammation.

Chemical Compounds of Berry-Derived Polyphenols and Their Effects on Gut Microbiota, Inflammation, and Cancer

Berry-derived polyphenols are bioactive compounds synthesized and secreted by several berry fruits. These polyphenols feature a diversity of chemical compounds, including phenolic acids and flavonoids. Here, we report the beneficial health effects of berry-derived polyphenols and their therapeutical application on gut-microbiota-related diseases, including inflammation and cancer. Pharmacokinetic investigations have confirmed the absorption, availability, and metabolism of berry-derived polyphenols. In vitro and in vivo tests, as well as clinical trials, showed that berry-derived polyphenols can positively modulate the gut microbiota, inhibiting inflammation and cancer development. Indeed, these compounds inhibit the growth of pathogenic bacteria and also promote beneficial bacteria. Moreover, berry-derived polyphenols exhibit therapeutic effects against different gut-microbiota-related disorders such as inflammation, cancer, and metabolic disorders. Moreover, these polyphenols can manage the inflammation via various mechanisms, in particular the inhibition of the transcriptional factor Nf-κB. Berry-derived polyphenols have also shown remarkable effects on different types of cancer, including colorectal, breast, esophageal, and prostate cancer. Moreover, certain metabolic disorders such as diabetes and atherosclerosis were also managed by berry-derived polyphenols through different mechanisms. These data showed that polyphenols from berries are a promising source of bioactive compounds capable of modulating the intestinal microbiota, and therefore managing cancer and associated metabolic diseases. However, further investigations should be carried out to determine the mechanisms of action of berry-derived polyphenol bioactive compounds to validate their safety and examinate their clinical uses.

Blueberry anthocyanin extracts protect against Helicobacter pylori-induced peptic epithelium injuries both in vitro and in vivo: the key role of MAPK/NF-κB pathway

PURPOSE

Anthocyanins are well-characterized by anti-oxidative and anti-inflammatory potentials. Peptic ulcers contribute to the development of severe gastric disorders. In the current study, the effects of blueberry anthocyanin extracts (BE) on the Helicobacter pylori lipopolysaccharide (LPS)-induced peptic epithelium injures were assessed and the associated mechanism driving the effects was explored by focusing on MAPK/NF-κB pathway.

METHODS

Peptic injures were induced in a mouse model using LPS plus ligation method and then the mice were treated with BE. Then changes in gastric histology, inflammatory response, and MAPK/NF-κB axis were detected. To reveal the role of MAPK/NF-κB axis in the effects of BE, human gastric epithelial cells (HGECs) were further subjected to co-treatment of BE, LPS, and MAPK activator.

RESULTS

The assays of mouse model showed that BE attenuated gastric epithelial injuries by improving epithelial structure and suppressing gastric inflammatory response, which was associated with the inhibition of MAPK/NF-κB axis. In in vitro assays, BE suppressed viability and production of cytokines, and induced apoptosis in LPS-treated HGECs. The re-activation of MAPK pathway counteracted the effects of BE by re-inducing cell viability and suppressing cell apoptosis.

CONCLUSIONS

The protective effects of BE against LPS-induced injuries in mouse stomach depended on the inhibition of both MAPK pathway and the downstream NF-κB signaling.

Dehydrocostus Lactone Suppresses Dextran Sulfate Sodium-Induced Colitis by Targeting the IKKα/β-NF-κB and Keap1-Nrf2 Signalling Pathways

Dehydrocostus lactone (DCL) is a major sesquiterpene lactone isolated from Aucklandia lappa Decne, a traditional Chinese herbal medicine that used to treat gastrointestinal diseases. This study aimed to examine the therapeutic effects of DCL on dextran sulfate sodium (DSS)-induced colitis with a focus on identifying the molecular mechanisms involved in DCL-mediated anti-inflammatory activity in macrophages. First, oral administration of DCL (5–15 mg/kg) not only ameliorated symptoms of colitis and colonic barrier injury, but also inhibited the expression of proinflammatory cytokines and myeloperoxidase in colon tissues in DSS-challenged mice. Furthermore, DCL also exhibited significant anti-inflammatory activity in LPS/IFNγ-stimulated RAW264.7 macrophages. Importantly, DCL significantly suppressed the phosphorylation and degradation of IκBα and subsequent NF-κB nuclear translocation, and enhanced the nuclear accumulation of Nrf2 in LPS/IFNγ-treated RAW264.7 cells. Mechanistically, DCL could directly interact with IKKα/β and Keap1, thereby leading to the inhibition of NF-κB signalling and the activation of Nrf2 pathway. Furthermore, DCL-mediated actions were abolished by dithiothreitol, suggesting a thiol-mediated covalent linkage between DCL and IKKα/β or Keap1. These findings demonstrated that DCL ameliorates colitis by targeting NF-κB and Nrf2 signalling, suggesting that DCL may be a promising candidate in the clinical treatment of colitis.

Polyphenol-Enriched Extracts of Prunus spinosa Fruits: Anti-Inflammatory and Antioxidant Effects in Human Immune Cells Ex Vivo in Relation to Phytochemical Profile

The fresh fruits of Prunus spinosa L., a wild plum species, are traditionally used for dietary purposes and medicinal applications in disorders related to inflammation and oxidative stress. This study aimed to investigate the phytochemical composition of the fruits in the function of fractionated extraction and evaluate the biological potential of the extracts as functional products in two models of human immune cells ex vivo. Fifty-seven phenolic components were identified in the extracts by UHPLC-PDA-ESI-MS³, including twenty-eight new for the analysed fruits. Fractionation enabled the enrichment of polyphenols in the extracts up to 126.5 mg gallic acid equivalents/g dw total contents, 91.3 mg/g phenolic acids (caffeoyl-, coumaroyl-, and feruloylquinic acids), 41.1 mg/g flavonoids (mostly quercetin mono-, di- and triglycosides), 44.5 mg/g condensed proanthocyanidins, and 9.2 mg/g anthocyanins (cyanidin and peonidin glycosides). The hydroalcoholic extract and phenolic-enriched fractions of the fruits revealed significant ability to modulate pro-oxidant, pro-inflammatory, and anti-inflammatory functions of human neutrophils and peripheral blood mononuclear cells (PBMCs): they strongly downregulated the release of reactive oxygen species, TNF-α, and neutrophils elastase, upregulated the secretion of IL-10, and slightly inhibited the production of IL-8 and IL-6 in the cells stimulated by fMLP, fMLP+cytochalasin B, and LPS, depending on the test. Correlation studies and experiments on the pure compounds indicated a significant contribution of polyphenols to these effects. Moreover, cellular safety was confirmed for the extracts by flow cytometry in a wide range of concentrations. The results support the traditional use of fresh blackthorn fruits in inflammatory disorders and indicate extracts that are most promising for functional applications.

Orally Deliverable Dual-Targeted Pellets for the Synergistic Treatment of Ulcerative Colitis

Purpose

The effective treatment of ulcerative colitis (UC) poses substantial challenges, and the aetiopathogenesis of UC is closely related to infectious, immunological and environmental factors. Currently, there is a considerable need for the development of orally bioavailable dosage forms that enable the effective delivery of therapeutic drugs to local diseased lesions in the gastrointestinal tract.

Methods

Berberine (BBR) and Atractylodes macrocephala Koidz (AM) volatile oil, derived from the Chinese herbs Coptis chinensis Franch and Atractylodes macrocephala Koidz, have anti-inflammatory and immunomodulatory activities. In this study, we prepared colon-targeted pellets loaded with BBR and stomach-targeted pellets loaded with AM volatile oil for the synergistic treatment of UC. The Box-Behnken design and β-cyclodextrin inclusion technique were used to optimize the enteric coating formula and prepare volatile oil inclusion compounds.

Results

The two types of pellets were spherical and had satisfactory physical properties. The pharmacokinetic results showed that the AUC and MRT values of the dual-targeted (DPs) pellets were higher than those of the control pellets. In addition, in vivo animal imaging confirmed that the DPs could effectively deliver BBR to the colon. Moreover, compared with sulfasalazine and monotherapy, DPs exerted a more significant anti-inflammatory effect by inhibiting the expression of inflammatory factors including IL-1β, IL-4, IL-6, TNF-α and MPO both in serum and tissues and enhancing immunity by decreasing the production of IgA and IgG.

Conclusion

The DPs play a synergistic anti-UC effect by exerting systemic and local anti-inflammatory and provide an effective oral targeted preparation for the treatment of UC.

IL-6 downregulates hepatic carboxylesterases via NF-κB activation in dextran sulfate sodium-induced colitis

Ulcerative colitis (UC) is associated with increased levels of inflammatory factors, which is attributed to the abnormal expression and activity of enzymes and transporters in the liver, affecting drug disposition in vivo. This study aimed to examine the impact of intestinal inflammation on the expression of hepatic carboxylesterases (CESs) in a mouse model of dextran sulfate sodium (DSS)-induced colitis. Two major CESs isoforms, CES1 and CES2, were down-regulated, accompanied by decreases in hepatic microsomal metabolism of clopidogrel and irinotecan. Meanwhile, IL-6 levels significantly increased compared with other inflammatory factors in the livers of UC mice. In contrast, using IL-6 antibody simultaneously reversed the down-regulation of CES1, CES2, pregnane X receptor (PXR), and constitutive androstane receptor (CAR), as well as the nuclear translocation of NF-κB in the liver. We further confirmed that treatment with NF-κB inhibitor abolished IL-6-induced down-regulation of CES1, CES2, PXR, and CAR in vitro. Thus, it was concluded that IL-6 represses hepatic CESs via the NF-κB pathway in DSS-induced colitis. These findings indicate that caution should be exercised concerning the proper and safe use of therapeutic drugs in patients with UC.

Neuroprotective effect of wild lowbush blueberry (Vaccinium angustifolium) on global cerebral ischemia/reperfusion injury in rats: Downregulation of iNOS/TNF-α and upregulation of miR-146a/miR-21 expression

This study aims to investigate the neuroprotective effect of wild lowbush blueberry on CIRI in rats. Accordingly, CIRI and reperfusion were induced in rats for 60 min and 24 h, respectively. Then, the mechanisms of the neuroprotective effects of BBE were investigated in the injury through evaluating miR-146a, miR-21, and their targets in a CIRI rat model. After that, the BBE (30, 60, and 120 mg/kg b.wt) was intraperitoneally injected for 14 days, then CIRI was induced by BCCAO for 60 min for ischemic stroke and reperfusion for 24 h. Several parameters including the oxidative stress levels in the hippocampus and serum were measured 24 h after the CIRI. The findings showed that the BBE significantly decreased the levels of malondialdehyde (MDA) and nitric oxide (NO) and increased ferric ion reducing antioxidant power (FRAP) levels in the hippocampus and serum following the stroke. The BBE also maximized the miR-146a and miR-21 expressions and moderated iNOS and TNF-α expressions in the hippocampus. Likewise, the BBE enlarged the CA1 and CA3 domains of the post-stroke pyramidal cell layers of the hippocampus. Overall, the results revealed that BBE had potent neuroprotective efficacy against CIRI via the effective modulation of neuroinflammatory cascades and protected neurons against ischemic death.

Vaccinium Species (Ericaceae): From Chemical Composition to Bio-Functional Activities

The genus Vaccinium L. (Ericaceae) includes more than 450 species, which mainly grow in cooler areas of the northern hemisphere. Vaccinium species have been used in traditional medicine of different cultures and the berries are widely consumed as food. Indeed, Vaccinium supplement-based herbal medicine and functional food, mainly from V. myrtillus and V. macrocarpon, are used in Europe and North America. Biological studies support traditional uses since, for many Vaccinium components, important biological functions have been described, including antioxidant, antitumor, anti-inflammatory, antidiabetic and endothelium protective activities. Vaccinium components, such as polyphenols, anthocyanins and flavonoids, are widely recognized as modulators of cellular pathways involved in pathological conditions, thus indicating that Vaccinium may be an important source of bioactive molecules. This review aims to better describe the bioactivity of Vaccinium species, focusing on anti-inflammatory and endothelial protective cellular pathways, modulated by their components, to better understand their importance for public health.

Discovery of a AHR pelargonidin agonist that counter-regulates Ace2 expression and attenuates ACE2-SARS-CoV-2 interaction

The severe acute respiratory syndrome (SARS)-CoV-2 is the pathogenetic agent of Corona Virus Induced Disease (COVID)19. The virus enters the human cells after binding to the angiotensin converting enzyme (ACE)2 receptor in target tissues. ACE2 expression is induced in response to inflammation. The colon expression of ACE2 is upregulated in patients with inflammatory bowel disease (IBD), highlighting a potential risk of intestinal inflammation in promoting viral entry in the human body. Because mechanisms that regulate ACE2 expression in the intestine are poorly understood and there is a need of anti-SARS-CoV-2 therapies, we have settled to investigate whether natural flavonoids might regulate the expression of Ace2 in intestinal models of inflammation. The results of these studies demonstrated that pelargonidin activates the Aryl hydrocarbon Receptor (AHR) in vitro and reverses intestinal inflammation caused by chronic exposure to high fat diet or to the intestinal braking-barrier agent TNBS in a AhR-dependent manner. In these two models, development of colon inflammation associated with upregulation of Ace2 mRNA expression. Colon levels of Ace2 mRNA were directly correlated with Tnf-α mRNA levels. Molecular docking studies suggested that pelargonidin binds a fatty acid binding pocket on the receptor binding domain of SARS-CoV-2 Spike protein. In vitro studies demonstrated that pelargonidin significantly reduces the binding of SARS-CoV-2 Spike protein to ACE2 and reduces the SARS-CoV-2 replication in a concentration-dependent manner. In summary, we have provided evidence that a natural flavonoid might hold potential in reducing intestinal inflammation and ACE2 induction in the inflamed colon in a AhR-dependent manner.

New Class of Anti-Inflammatory Therapeutics Based on Gold (III) Complexes in Intestinal Inflammation-Proof of Concept Based on In Vitro and In Vivo Studies

Inflammatory bowel diseases (IBD) are at the top of the worldwide rankings for gastrointestinal diseases as regards occurrence, yet efficient and side-effect-free treatments are currently unavailable. In the current study, we proposed a new concept for anti-inflammatory treatment based on gold (III) complexes. A new gold (III) complex TGS 121 was designed and screened in the in vitro studies using a mouse macrophage cell line, RAW264.7, and in vivo, in the dextran sulphate sodium (DSS)-induced mouse model of colitis. Physicochemical studies showed that TGS 121 was highly water-soluble; it was stable in water, blood, and lymph, and impervious to sunlight. In lipopolysaccharide (LPS)-stimulated RAW264.7 cells, the complex showed a potent anti-inflammatory profile, as evidenced in neutral red uptake and Griess tests. In the DSS-induced mouse model of colitis, the complex administered in two doses (1.68 μg/kg, intragastrically, and 16.8 μg/kg, intragastrically, once daily) produced a significant (* p < 0.05) anti-inflammatory effect, as shown by macroscopic score. The mechanism of action of TGS 121 was related to the enzymatic and non-enzymatic antioxidant system; moreover, TGS 121 induced changes in the tight junction complexes expression in the intestinal wall. This is the first study proving that gold (III) complexes may have therapeutic potential in the treatment of IBD.

Role of dietary polyphenols on gut microbiota, their metabolites and health benefits

The beneficial health roles of dietary polyphenols in preventing oxidative stress related chronic diseases have been subjected to intense investigation over the last two decades. As our understanding of the role of gut microbiota advances our knowledge of the antioxidant and anti-inflammatory functions of polyphenols accumulates, there emerges a need to examine the prebiotic role of dietary polyphenols. This review focused onthe role of different types and sources of dietary polyphenols on the modulation of the gut microbiota, their metabolites and how they impact on host health benefits. Inter-dependence between the gut microbiota and polyphenol metabolites and the vital balance between the two in maintaining the host gut homeostasis were discussed with reference to different types and sources of dietary polyphenols. Similarly, the mechanisms behind the health benefits by various polyphenolic metabolites bio-transformed by gut microbiota were also explained. However, further research should focus on the importance of human trials and profound links of polyphenols-gut microbiota-nerve-brain as they provide the key to unlock the mechanisms behind the observed benefits of dietary polyphenols found in vitro and in vivo studies.

Compound sophorae decoction enhances intestinal barrier function of dextran sodium sulfate induced colitis via regulating notch signaling pathway in mice

BACKGROUND

Compound sophorae decoction (CSD), a Chinese Herbal decoction, is frequently clinically prescribed for patients suffered from ulcerative colitis (UC) characterized by bloody diarrhea. Yet, the underlying mechanism about how this formulae works is remain elusive.

METHODS

In the present study, the experimental colitis in C57BL/6 J mice was induced by oral administration of standard diets containing 3% dextran sodium sulfate (DSS), and CSD was given orally for treatment at the same time. The clinical symptoms including stool and body weight were recorded each day, and colon length and its histopathological changes were observed. Apoptosis of colonic epithelium was studied by detecting protein expression of cleaved caspase-3, and cell proliferation by Ki-67 immunohistochemistry. Tight junction complex like ZO-1 and occludin were also determined by transmission electron microscope and immunofluorescence. The concentration of FITC-dextran 4000 was measured to evaluate intestinal barrier permeability and possible signaling pathway was investigated. Mucin2 (MUC2) and notch pathway were tested through western blot. The M1/M2 ratio in spleen and mesenteric lymph nodes were detected by flow cytometry. And the mRNA levels of iNOS and Arg1 were examined by qRT-PCR.

RESULTS

CSD could significantly alleviate the clinical manifestations and pathological damage. Body weight loss and DAI score of mice with colitis were improved and shortening of colon was inhibited. The administration of CSD was able to reduce apoptotic epithelial cells and facilitate epithelial cell regeneration. Increased intestinal permeability was reduced in DSS-induced colitis mice. In addition, CSD treatment obviously up-regulated the expression of ZO-1 and occludin and the secretion of MUC2, regulated notch signaling, and decreased the ratio of M1/M2.

CONCLUSIONS

These data together suggest that CSD can effectively mitigate intestinal inflammation, promote phenotypic change in macrophage phenotype and enhance colonic mucosal barrier function by, at least in part, regulating notch signaling in mice affected by DSS-induced colitis.

Polyphenol Extract of Moringa Oleifera Leaves Alleviates Colonic Inflammation in Dextran Sulfate Sodium-Treated Mice

Moringa oleifera Lam. is an essential herb used for the treatment of inflammation, diabetes, high blood pressure, and other diseases. In this study, phenolic extracts of M. oleifera leaves were obtained and analyzed. The results showed that the main identifiable phenols were astragalin, chlorogenic acid, isoquercitrin, kaempferitrin, luteolin, quercetin, and rutin. The effects of M. oleifera polyphenol extract (MOPE) on experimental colitis induced by 3% dextran sulfate sodium (DSS) were investigated. The results showed that oral administration of MOPE significantly alleviated the symptoms of DSS-induced colitis. MOPE significantly reduced weight loss, the disease activity index, colon shortening, and mucosal damage. In addition, MOPE attenuated the infiltration of CD3⁺ T cells, CD177⁺ neutrophils, and F4/80⁺ macrophages and significantly inhibited the secretion of IL-6 and TNF-α. After the MOPE administration, the expression of proteins associated with the NF-κB signaling pathway changed. Specifically, compared with that of the DSS group, the protein expression of NF-κB p65 and p-IκBα was downregulated, and the expression of IκBα was upregulated. This study revealed the anti-inflammatory effects and mechanisms of MOPE in the colon, indicating its potential use in preventing inflammation-driven diseases.

Pinto beans modulate the gut microbiome, augment MHC II protein, and antimicrobial peptide gene expression in mice fed a normal or western-style diet

The onset of type 2 diabetes in obesity is associated with gut dysbiosis and a failure to confine commensal bacteria and toxins to the gut lumen while prebiotics may prevent these effects. This study evaluated the effects of pinto beans (PB) supplementation on cecal bacteria, short-chain fatty acids (SCFAs), distal ileal antigen presentation marker (major histocompatibility complex [MHC] II) and antimicrobial peptide genes during short-term high-fat, high sucrose (HFS) feeding. Six-week-old, male C57BL/6J mice were randomly assigned to four groups (n=12/group), and fed a control (C) or HFS diet with or without cooked PB (10%, wt/wt) for 30 days. Supplemental PB in both the C and HFS diets decreased the abundance of Tenericutes and the sulfate-reducing bacteria Bilophila. In contrast, PB raised the abundance of taxa within the SCFAs-producing family, Lachnospiraceae, compared to groups without PB. Consequently, fecal butyric acid was significantly higher in PB-supplemented groups compared to C and HFS groups. PB reversed the HFS-induced ablation of the distal ileal STAT3 phosphorylation, and up-regulated antimicrobial peptide genes (Reg3γ and Reg3β). Furthermore, the expression of MHC II protein was elevated in the PB supplemented groups compared to C and HFS. Tenericutes and Bilophilia negatively correlated with activated STAT3 and MHC II proteins. Finally, supplemental PB improved fasting blood glucose, glucose tolerance and suppressed TNFα and inducible nitric oxide synthase mRNA in the visceral adipose tissue. Put together, the beneficial impact of PB supplementation on the gut may be central to its potential to protect against diet-induced inflammation and impaired glucose tolerance.

Chlorogenic Acid Improves Symptoms of Inflammatory Bowel Disease in Interleukin-10 Knockout Mice

Inflammatory bowel disease (IBD) is a chronic intestinal inflammation that is highly prevalent worldwide. Interleukin (IL)-10 can effectively inhibit negative cascades such as the production of inflammatory mediators (inducible nitric oxide synthase [iNOS], cyclooxygenase-2), accumulation of inflammatory infiltrates (macrophages, eosinophils, neutrophils), toxicity (lower T cell subsets), and secretion of pro-inflammatory cytokines (IL-1β, TNF-α) in tissues such as the spleen, mesenteric lymph nodes (MLN), Peyer's patch (PP), and colon. In this study, we investigated whether chlorogenic acid (CHA) can regulate inflammation in IL-10 knockout (KO) mice used as an IBD animal model. CHA significantly increased the ratio of CD4⁺/CD8⁺, T cell subsets in PP, and MLN of IL-10 KO mice. In addition, CHA also morphologically attenuated colon inflammation in IL-10 KO mice. We demonstrated that CHA significantly reduced the expression levels of iNOS, IL-1β, TNF-α, which were highly expressed in IL-10 KO mice. Therefore, CHA may provide beneficial effects for improving IBD by decreasing inflammations.

Berry polyphenols metabolism and impact on human gut microbiota and health

Berries are rich in phenolic compounds such as phenolic acids, flavonols and anthocyanins. These molecules are often reported as being responsible for the health effects attributed to berries. However, their poor bioavailability, mostly influenced by their complex chemical structures, raises the question of their actual direct impact on health. The products of their metabolization, however, may be the most bioactive compounds due to their ability to enter the blood circulation and reach the organs. The main site of metabolization of the complex polyphenols to smaller phenolic compounds is the gut through the action of microorganisms, and reciprocally polyphenols and their metabolites can also modulate the microbial populations. In healthy subjects, these modulations generally lead to an increase in Bifidobacterium, Lactobacillus and Akkermansia, therefore suggesting a prebiotic-like effect of the berries or their compounds. Finally, berries have been demonstrated to alleviate symptoms of gut inflammation through the modulation of pro-inflammatory cytokines and have chemopreventive effects towards colon cancer through the regulation of apoptosis, cell proliferation and angiogenesis. This review recapitulates the knowledge available on the interactions between berries polyphenols, gut microbiota and gut health and identifies knowledge gaps for future research.

Chemopreventive Effect of Dietary Anthocyanins against Gastrointestinal Cancers: A Review of Recent Advances and Perspectives

Anthocyanins are a group of dietary polyphenols, abundant mainly in fruits and their products. Dietary interventions of anthocyanins are being studied extensively related to the prevention of gastrointestinal (GI) cancer, among many other chronic disorders. This review summarizes the hereditary and non-hereditary characteristics of GI cancers, chemistry, and bioavailability of anthocyanins, and the most recent findings of anthocyanin in GI cancer prevention through modulating cellular signaling pathways. GI cancer-preventive attributes of anthocyanins are primarily due to their antioxidative, anti-inflammatory, and anti-proliferative properties, and their ability to regulate gene expression and metabolic pathways, as well as induce the apoptosis of cancer cells.

Protective Effects of Yiqi Xingnao Oral Liquid on Cerebral Ischemia-Reperfusion Injury in Rats and Its Related Mechanisms

Purpose

This study aimed to investigate the effects of different concentrations of Yiqi Xingnao (YQXN) oral liquid on cerebral ischemia/reperfusion (I/R) injury in rats and YQXN's related mechanisms.

Methods

Rats were pretreated with 3 mL/kg, 6 mL/kg, and 12 mL/kg YQXN and Naoxuekang capsule (NXK). Afterwards, cerebral I/R model rats were established by a middle cerebral artery occlusion surgery. Neurological deficits, histopathology, and cerebral infarction volume were used to evaluate the effects of YQXN. Evans blue and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining were utilized to determine the blood-brain barrier permeability and cell apoptosis, respectively. The expression of VEGF and Bcl-2 was analyzed by real-time quantification PCR (RT-qPCR) and western blot. The malondialdehyde (MDA) content and superoxide dismutase (SOD) activity were measured using corresponding assay kits.

Results

The rats pretreated with YQXN had improved neurological deficits, reduced infarct volume and blood-brain barrier permeability, and ameliorated ischemia-induced morphology change in injured brain tissues. TUNEL staining results showed that different concentrations of YQXN inhibited cell apoptosis of neurocytes in I/R rats. Besides, RT-qPCR and western blot analyses indicated that the expression levels of VEGF and Bcl-2 were significantly upregulated by YQXN compared with the I/R group (P < 0.05). Additionally, rats in the I/R group had lower SOD activity and higher MDA content than those in the sham-operated group, while their levels were recovered by YQXN (P < 0.05).

Conclusion

YQXN could alleviate cerebral I/R injury by suppressing blood-brain barrier permeability, neuron apoptosis, and oxidative stress, promoting angiogenesis.

Interaction of Polyphenols as Antioxidant and Anti-Inflammatory Compounds in Brain-Liver-Gut Axis

Oxidative stress plays an important role in the onset as well as the progression of inflammation. Without proper intervention, acute inflammation could progress to chronic inflammation, resulting in the development of inflammatory diseases. Antioxidants, such as polyphenols, have been known to possess anti-oxidative properties which promote redox homeostasis. This has encouraged research on polyphenols as potential therapeutics for inflammation through anti-oxidative and anti-inflammatory pathways. In this review, the ability of polyphenols to modulate the activation of major pathways of inflammation and oxidative stress, and their potential to regulate the activity of immune cells are examined. In addition, in this review, special emphasis has been placed on the effects of polyphenols on inflammation in the brain–liver–gut axis. The data derived from in vitro cell studies, animal models and human intervention studies are discussed.

Interventions of natural and synthetic agents in inflammatory bowel disease, modulation of nitric oxide pathways

Inflammatory bowel disease (IBD) refers to a group of disorders characterized by chronic inflammation of the gastrointestinal (GI) tract. The elevated levels of nitric oxide (NO) in serum and affected tissues; mainly synthesized by the inducible nitric oxide synthase (iNOS) enzyme; can exacerbate GI inflammation and is one of the major biomarkers of GI inflammation. Various natural and synthetic agents are able to ameliorate GI inflammation and decrease iNOS expression to the extent comparable with some IBD drugs. Thereby, the purpose of this study was to gather a list of natural or synthetic mediators capable of modulating IBD through the NO pathway. Electronic databases including Google Scholar and PubMed were searched from 1980 to May 2018. We found that polyphenols and particularly flavonoids are able to markedly attenuate NO production and iNOS expression through the nuclear factor κB (NF-κB) and JAK/STAT signaling pathways. Prebiotics and probiotics can also alter the GI microbiota and reduce NO expression in IBD models through a broad array of mechanisms. A number of synthetic molecules have been found to suppress NO expression either dependent on the NF-κB signaling pathway (i.e., dexamethasone, pioglitazone, tropisetron) or independent from this pathway (i.e., nicotine, prednisolone, celecoxib, β-adrenoceptor antagonists). Co-administration of natural and synthetic agents can affect the tissue level of NO and may improve IBD symptoms mainly by modulating the Toll like receptor-4 and NF-κB signaling pathways.

Quyushengxin Formula Causes Differences in Bacterial and Phage Composition in Ulcerative Colitis Patients

Background

Ulcerative colitis (UC) is a chronic inflammatory disease that affects the colon and the rectum. Recently, some studies have shown that microorganisms in the gut play important roles in many chronic diseases such as UC.

Methods

To study the candidate viruses and bacteria involved in UC and to investigate the therapeutic mechanism of Quyushengxin formula (QYSX) in UC patients, metagenomic sequencing was performed on the feces from healthy donors and UC patients before and after QYSX treatment.

Results

QYSX improved the symptoms of UC. In all participants, Caudovirales and Herpesvirales were the most dominant viruses. The abundance of Caudovirales in UC patients was significantly higher than that in the normal controls, while QYSX restored Caudovirales abundance. Furthermore, the abundance of crAssphage was enhanced in UC patients compared with the normal control, while the diversity was then decreased after QYSX treatment. However, there was no significant difference (P > 0.05). Additionally, other non-crAssphage bacteriophages including phiST, SP-10, and phi17:2 were higher in UC patients and QYSX decreased these viruses, while the trends of MED4−213, P-HM1, and P−HM2 were adverse. Interestingly, PhiDP23.1 was only found in UC patients before and after QYSX treatment. In addition, Bifidobacterium, Bacteroidetes, Prevotellaceae, Actinobacteria, and Corynebacteriales were the biomarkers in UC patients after QYSX treatment due to their high abundance. GO terms and KEGG analysis showed that the identified gut microbiome was involved in many biological processes and pathways.

Conclusions

QYSX could regulate disordered gut microbiome and phages, indicating that QYSX has great therapeutic potential for UC.

Grape peel powder attenuates the inflammatory and oxidative response of experimental colitis in rats by modulating the NF-κB pathway and activity of antioxidant enzymes

Most phenolic compounds and dietary fiber reach intact to the colon. We hypothesized that grape peel powder (GPP), a rich source of these bioactive compounds, modulates inflammatory and oxidative pathways collaborating to attenuate colonic damage in experimental colitis. To determine which bioactive fraction would be responsible for this effect, the aim of this study was to evaluate the effect of dietary supplementation with whole GPP or the isolated bioactive-rich fractions from GPP (extractable polyphenols [EP], dietary fiber and fiber-bound polyphenols [NEP-F], and dietary fiber) in rats with experimental colitis. Colitis was induced by intrarectal injection of 2,4,6-trinitrobenzene sulfonic acid (TNBS) after 15 days of dietary supplementation. EP diet did not reverse the decrease in feed intake and indeed worsened colon shortening and increased spleen weight; however, these effects were not observed for the GPP group, which had polyphenols associated to the matrix besides the extractable ones. Colitis impaired the activity of colonic antioxidant enzymes and increased lipid peroxidation, protein oxidation, nitric oxide (NO) levels, and proinflammatory cytokines in serum and in the colon tissue. GPP restored the activity of antioxidant enzymes and decreased colon oxidation and NO levels. All grape peel fractions reduced the protein expression of the inhibitor of kappa kinase beta and NO levels in colon tissue, but only NEP-F reduced the expression of phosphorylated nuclear factor kappa B and myeloperoxidase activity. Results demonstrated that GPP attenuates inflammatory and oxidative response in TNBS-induced colitis by downregulating the nuclear factor kappa B pathway and upregulating antioxidant enzymes, with NEP-F being the fraction most likely associated to these protective effects.

Dietary Intake of Whole Strawberry Inhibited Colonic Inflammation in Dextran-Sulfate-Sodium-Treated Mice via Restoring Immune Homeostasis and Alleviating Gut Microbiota Dysbiosis

Strawberry (Fragaria chiloensis) is a major edible berry with various potential health benefits. This study determined the protective effects of whole strawberry (WS) against dextran-sulfate-sodium-induced colitis in mice. In colitic mice, dietary WS reduced the disease activity index, prevented the colon shortening and spleen enlargement, and alleviated the colonic tissue damages. The abundance of proinflammatory immune cells was reduced by dietary WS in the colonic mucosa, which was accompanied by the suppression of overproduction of proinflammatory cytokines. Western blotting and immunohistochemical analysis revealed that dietary WS decreased the expression of proinflammatory proteins in the colonic mucosa. Moreover, dietary WS partially reversed the alteration of gut microbiota in the colitic mice by increasing the abundance of potential beneficial bacteria, e.g., Bifidobacterium and Lactobacillus, and decreasing the abundance of potential harmful bacteria, e.g., Dorea and Bilophila. Dietary WS also restored the decreased production of short-chain fatty acids in the cecum of the colitic mice. The results revealed the anti-inflammatory effects and mechanisms of dietary WS in the colon, which is critical for the rational utilization of strawberry for the prevention of inflammation-driven diseases.

The Aryl Hydrocarbon Receptor (AhR) Mediates the Counter-Regulatory Effects of Pelargonidins in Models of Inflammation and Metabolic Dysfunctions

Pelargonidins are anthocyanidins thought to be beneficial for the human health, although controversies exist over the doses needed and the unclear mechanism of action, along with poor systemic bioavailability. One putative target of pelargonidins is the aryl hydrocarbon receptor (AhR). A synthetic pelargonidin (Mt-P) was synthesized by the methylation of the pelargonidin (the natural compound indicated as P). Mt-P transactivated the AhR with an EC50 of 1.97 µM and was ~2-fold more potent than the natural compound. In vitro Mt-P attenuated pro-inflammatory activities of Raw264.7 macrophage cells in an AhR-dependent manner. In vivo, administration of the Mt-P in Balb/c mice resulted in a dose-dependent attenuation of signs and symptoms of colitis induced by TNBS. A dose of 5 mg/kg Mt-P, but not the natural compound P, reversed intestinal inflammation and increased expression of Tnf-α, Ifn-ƴ, and Il-6, while promoted the expansion of regulatory T cells and M2 macrophages. In C57BL/6J mice fed a high fat diet (HFD), Mt-P attenuated body weight gain, intestinal and liver inflammation, and ameliorated insulin sensitivity, while worsened liver steatosis by up-regulating the liver expression of Cd36 and Apo100b. These effects were abrogated by AhR gene ablation. Mt-P is a synthetic pelargonidin endowed with robust AhR agonist activity that exerts beneficial effects in murine models of inflammation and metabolic dysfunction.

Aronia Berry Supplementation Mitigates Inflammation in T Cell Transfer-Induced Colitis by Decreasing Oxidative Stress

Oxidative stress is involved in the pathogenesis and progression of inflammatory bowel disease. Consumption of aronia berry inhibits T cell transfer colitis, but the antioxidant mechanisms pertinent to immune function are unclear. We hypothesized that aronia berry consumption could inhibit inflammation by modulating the antioxidant function of immunocytes and gastrointestinal tissues. Colitis was induced in recombinase activating gene-1 deficient (Rag1^-/-) mice injected with syngeneic CD4⁺CD62L⁺ naïve T cells. Concurrent with transfer, mice consumed either 4.5% w/w aronia berry-supplemented or a control diet for five weeks. Aronia berry inhibited intestinal inflammation evidenced by lower colon weight/length ratios, 2-deoxy-2-[¹⁸F]fluoro-d-glucose (FDG) uptake, mRNA expressions of tumor necrosis factor alpha (TNF-α), and interferon gamma (IFN-γ) in the colon. Aronia berry also suppressed systemic inflammation evidenced by lower FDG uptake in the spleen, liver, and lung. Colitis induced increased colon malondialdehyde (MDA), decreased colon glutathione peroxidase (GPx) activity, reduced glutathione (rGSH) level, and suppressed expression of antioxidant enzymes in the colon and mesenteric lymph node (MLN). Aronia berry upregulated expression of antioxidant enzymes, prevented colitis-associated depletion of rGSH, and maintained GPx activity. Moreover, aronia berry modulated mitochondria-specific antioxidant activity and decreased splenic mitochondrial H₂O₂ production in colitic mice. Thus, aronia berry consumption inhibits oxidative stress in the colon during T cell transfer colitis because of its multifaceted antioxidant function in both the cytosol and mitochondria of immunocytes.

Comparison of Antioxidant and Anti-Inflammatory Effects of Honey and Spirulina platensis with Sulfasalazine and Mesalazine on Acetic Acid-Induced Ulcerative Colitis in Rats

Background:

Antioxidant therapy has gained attention for the treatment of ulcerative colitis (UC). The excessive generation of reactive oxygen/nitrogen species in the gastrointestinal tract increases oxidative stress, thereby leading to antioxidant defense depletion, lipid peroxidation, inflammation, tissue damage, and ulceration. Spirulina platensis (SP) and honey are excellent sources of potent antioxidants such as polyphenols and other bioactive compounds. We aimed to investigate antioxidant and anti-inflammatory effects of honey and SP in comparison with sulfasalazine (SSZ) and mesalazine on acetic acid-induced colitis (AA-colitis) in rats.

Materials and Methods:

Fifty-six Sprague Dawley male rats were allocated to seven groups, with each group comprising eight rats. UC was induced, except in normal controls (NC). All groups received oral treatments for seven days. The normal saline solution of 2 mL was intrarectally administered to the NC group. The AA-colitis and NC groups received 2 mL acetic acid intrarectally as a single dose and 2 mL normal saline for seven consecutive days orally. The mesalazine group received 100 mg/kg mesalazine, the SSZ group 360 mg/kg SSZ, the honey or H group 1 mL honey diluted with 1 mL distilled water, the SH group 1g/kg SP and 1 mL honey, and the SP group 1g/kg SP. After clinical activity score assessment, the rats were sacrificed. Colonic weight/length ratio, prostaglandin E2 (PGE2), myeloperoxidase (MPO), nitric oxide (NO), malondialdehyde (MDA), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), glutathione peroxidase (GPx), total antioxidant capacity (TAC), reduced glutathione (GSH), and superoxide dismutase (SOD) were measured. Colonic histopathological changes were observed microscopically.

Results:

Treatment of UC with SP, honey, and combination regimen significantly reduced TNF-α, IL-1β, IL-6, MDA, MPO, NO, and PGE2, and increased TAC, GSH, GPx, and SOD in interventional groups compared to the AA-colitis group (P<0.05).

Conclusion:

Honey and SP might be beneficial food supplements for medical nutrition therapy in UC.

Etiology and pathogenesis of ulcerative colitis from the perspective of modern medicine

According to the modern medical research on ulcerative colitis (UC), many factors, including environmental and psychological factors as well as hereditary susceptibility, participate in the pathogenesis of UC, which is a complex process involving chronic inflammation. Intestinal mucosal barrier damage and disorder of neuroendocrine immune network, such as dysfunction of biological barrier, immune barrier, and brain-gut peptide, play a critical role in this process. Meanwhile, we suggest that the microbiome-gut-brain axis is the key to elucidating the pathogenesis of UC.