Histological Colitis Score Research Articles

Protective effects of ginsenosides on ulcerative colitis: a meta-analysis and systematic review to reveal the mechanisms of action.

Ulcerative colitis (UC) is a chronic inflammatory disease of the colon. Ginsenoside may be an ideal agent for UC treatment. However, its efficacy and safety are unknown. We aim to conduct a systematic evaluation to assess the effects and potential mechanisms of ginsenosides in animal models of UC. Six electronic databases will be searched (PubMed, Embase, Web of Science, China Knowledge Network (CNKI), China Science and Technology Journal Database (CQVIP), and Wanfang Data Knowledge). SYRCLE list will be used to assess the quality of literature, and STATA 15.1 for data analysis. Time-dose effects analysis will be used to reveal the time-dosage response relations between ginsenosides and UC. Ultimately, fifteen studies involving 300 animals were included. Preliminary evidence was shown that ginsenosides could reduce Disease Activity Index (DAI) scores, weight loss, histological colitis score (HCS), spleen weight, Malondialdehyde (MDA), Myeloperoxidase (MPO) activity, interleukin-1β (IL-1β), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α) and increase colon length (CL), myeloperoxidase (GSH), interleukin 4 (IL-4), interleukin 10 (IL-10), Zonula Occludens-1 (ZO-1) and occludin. Results of time-dose interval analysis indicated that ginsenosides at a dosage of 5-200mg/kg with an intervention time of 7-28days were relatively effective. Preclinical evidence suggests that ginsenoside is a novel treatment for UC. And the mechanisms of ginsenosides in treating UC may involve anti-inflammatory, antioxidant, barrier protection, intestinal flora regulation, and immune regulation. Although, due to the high heterogeneity, further large-scale and high-quality preclinical studies are needed to examine the protection of ginsenosides against UC.

Electroacupuncture alleviates ulcerative colitis by targeting CXCL1: evidence from the transcriptome and validation.

We aimed to use transcriptomics, bioinformatics analysis, and core gene validation to identify the core gene and potential mechanisms for electroacupuncture (EA) treatment of ulcerative colitis (UC). EA was performed in mice after induction of UC via dextran sodium sulfate. Body weight, disease activity index (DAI), colon length, and hematoxylin-eosin of the colon tissue were used to evaluate the effects of EA. Mice transcriptome samples were analyzed to identify the core genes, and further verified with human transcriptome database; the ImmuCellAI database was used to analyze the relationship between the core gene and immune infiltrating cells (IICs); and immunofluorescence was used to verify the results. EA could reduce DAI and histological colitis scores, increase bodyweight and colon length, and improve the expression of local and systemic proinflammatory factors in the serum and colon of UC mice. Eighteen co-differentially expressed genes were identified by joint bioinformatics analyses of mouse and human transcriptional data; Cxcl1 was the core gene. EA affected IICs by inhibiting Cxcl1 expression and regulated the polarization of macrophages by affecting the Th1 cytokine IFN-γ, inhibiting the expression of CXCL1. CXCL1 is the target of EA, which is associated with the underlying immune mechanism related to Th1 cytokine IFN-γ.

Low dose dietary contamination with deoxynivalenol mycotoxin exacerbates enteritis and colorectal cancer in mice

BackgroundThe mycotoxin deoxynivalenol (DON) is a frequent contaminant of grain and cereal products worldwide. Exposure to DON can cause gastrointestinal inflammation, disturb gut barrier function, and induce gut dysbiosis in vivo under basal conditions, but little is known about the effects of DON ingestion in individuals with pre-existing gastrointestinal disease. ObjectivesMice were orally exposed to 10 and 100 μg/kg bw/day of DON, corresponding to 10 to 100-fold human tolerable daily intake concentrations, and to the translation in mice of current human daily intake. The effects of DON exposure were explored under steady-state conditions, and in murine models of enteritis and colorectal cancer (CRC). ResultsAfter 8 days of DON exposure, an increase of histomorphological and molecular parameters of epithelial proliferation were observed in normal mice, from the duodenum to the colon. The same exposure in a murine model of indomethacin-induced enteritis led to exacerbation of lesion development and induction of ileal cytokines. DON exposure also worsened the development of colitis-associated CRC in mice as shown by increases in endoscopic and histological colitis scores, tumor grades, and histological hyperplasia. In colon of DON-exposed mice, upstream and downstream ERK signaling genes were upregulated including Mapk1, Mapk3, Map 2k1, Map2k2 core ERK pathway effectors, and Bcl2 and Bcl2l1 antiapoptotic genes. The effects observed in the CRC model were associated with alterations in cecal microbiota taxonomic composition and metabolism of bacterial fucose and rhamnose. Strong Spearman's correlations were revealed between the relative abundance of the changed bacterial genera and CRC-related variables. DiscussionIngestion of DON mycotoxin at concentrations representative of human real-world exposure worsened the development of indomethacin-induced enteritis and colitis-associated CRC in mice. Our results suggest that even at low doses, which are currently tolerated in the human diet, DON could promote the development of intestinal inflammatory diseases and CRC.

Matrix metalloproteinases are key targets of acupuncture in the treatment of ulcerative colitis.

The aim of this study was to elucidate the key targets of acupuncture in the colon of ulcerative colitis (UC) mice model using full-length transcriptome sequencing. 2.5% dextran sodium sulfate (DSS)-induced colitis mice were treated with or without acupuncture. Intestinal pathology was observed, and full transcriptome sequencing and bioinformatic analysis were performed. The results demonstrated that acupuncture treatment reduced the UC symptoms, disease activity index score, and histological colitis score and increased body weight, colon length, and the number of intestinal goblet cells. In addition, acupuncture can also decrease the expression of necrotic biomarker phosphorylates mixed lineage kinase domain-like pseudo kinase (p-MLKL). Full-length transcriptome analysis indicated that acupuncture reversed the expression of 987 of the 1918 upregulated differentially expressed genes (DEGs), and 632 of the 1351 downregulated DEGs induced by DSS. DEGs regulated by acupuncture were mainly involved in inflammatory responses and intestinal barrier pathways. The protein-protein interaction network analysis revealed that matrix metalloproteinases (MMPs) are important genes regulated by acupuncture. Gene set enrichment analysis revealed that extracellular matrix (ECM)-receptor interaction was an important target of acupuncture. In addition, alternative splicing analysis suggested that acupuncture improved signaling pathways related to intestinal permeability, the biological processes of xenobiotics, sulfur compounds, and that monocarboxylic acids are closely associated with MMPs. Overall, our transcriptome analysis results indicate that acupuncture improves intestinal barrier function in UC through negative regulation of MMPs expression.

Early life stress in mice leads to impaired colonic corticosterone production and prolonged inflammation following induction of colitis

Early life stress (ELS) is an environmental trigger linked to increased risk of inflammatory bowel disease (IBD). Our goal was to identify mechanisms whereby ELS in mice affects susceptibility to, and/or severity of, intestinal inflammation. We hypothesized that ELS alters the delicate balance of typical homeostatic mediators in the intestinal microenvironment, predisposing ELS-exposed individuals to IBD onset or worsened disease upon a pro-inflammatory triggering event within the gut. We utilized 2 published animal models of ELS. In the first model, newborn mice were separated from the dam daily for 4-8 hours beginning on postnatal day 2, then weaned early on postnatal day 17. Normally reared (NR) control mice were left undisturbed with the dams until standard weaning on postnatal day 21. In the second model, dams were fed the synthetic glucocorticoid – dexamethasone, or vehicle ad libitum in drinking water (3 μg/mL) on post-partum days 1-14. Colitis was induced in 4-week-old mice via intraperitoneal injection of IL-10 receptor blocking antibody (100 μg) every 5 days for 15 days. Five or 15 days later, histological colitis scores and colonic transcripts for Tnf, glucocorticoid receptors, and steroidogenic enzymes were measured. ELS-exposed mice displayed altered mucosa-associated immune cell balances, with an initial deficit in anti-inflammatory IL-10-producing CD4 T cells at 4-wks of age (n≥11, p<0.05), followed by an increase in IFNγ-producing CD4 T cells at 8-wks of age (n≥7, p<0.05). ELS-exposed mice also displayed reduced levels of the glucocorticoid, corticosterone in the plasma (n≥10, p<0.01) as well as locally within the colon (n≥7, p<0.05). Upon colitis induction, NR control animals showed improvements in indices of inflammation following cessation of IL-10 receptor blockade, whereas ELS-exposed animals maintained high levels of intestinal Tnf (n≥7, p<0.01) and histological signs of colitis (n≥7, p<0.05). In colitic animals, prior exposure to ELS was associated with significantly lower expression of genes associated with corticosterone synthesis ( Cyp11a1; n≥5, p<0.05) and responsiveness ( Nr3c1, Nr5a2; n≥5, p<0.01). Finally, ex-vivo TNF stimulation of colonic crypt cells from ELS mice led to increased inhibition of corticosterone synthesis, relative to NR control mice (n≥4, p<0.05). Our study identifies impaired local colonic glucocorticoid production and responsiveness as a potential mechanism whereby ELS predisposes to chronic colitis in susceptible hosts. Crohn's and Colitis Foundation Research Initiatives Award This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

DOP47 Gut microbiome contributes to the development of immune checkpoint inhibitor-related colitis

Abstract Background The gut microbiota is implicated in shaping immune checkpoint inhibitors (ICIs) efficacy, but relatively little is known about how the microbiota influences immune-related adverse events (irAEs). Our study aimed to explore the association and causal relationship between gut microbiome and immune checkpoint inhibitor-related colitis. Methods We collected faecal samples from 32 patients with advanced malignant tumor patients developing irAE after anti-PD-1 therapy from May 2020 to Aug 2021. Faecal samples were analyzed by 16s rDNA amplicon sequencing method on Illumina MiSeq (PE300) sequencing platform. We also performed faecal microbiota transplantation (FMT) for antibiotic-treated mice with samples from patients with colitic irAE and without irAE. Results We compared the microbiota between 8 colitic irAE and 24 non-colitic irAE patients. Principal coordinates analysis (PCoA) plot showed significant difference of microbiota composition by Adonis analysis (P=0.003) (Fig. 1A). LEfSe analysis detected a lower abundance of Bacteroidota and a higher abundance of Proteobacteria at the phylum level and a lower abundance of Bacteroides and Bifidobacterium and higher abundance of Enterococcus at the genus level in colitic irAE (Fig. 1B). The total abundance of major butyrate-producing bacteria was lower in colitic irAE compared with non-colitic irAE patients (P=0.018) (Fig. 1C). Functional prediction analyses revealed different abundances of environmental information processing, genetic information processing, and metabolic pathways between colitic and non-colitic irAE patients (Fig. 1D). By FMT experiments in mice, we sought to explore the causal relationship between microbiota immune-related colitis. After injection of anti-PD-1 and anti-CTLA-4, three of nine colitic-irAE-FMT mice developed fatal severe colitis, while all nine non-irAE-FMT mice survived without colitis (P=0.052). The three colitic mice showed more rapid weight loss and higher disease activity index (DAI) scores compared with other mice (Fig. 2A and B). The histological colitis score in the irAE-FMT-Sac. mouse (14 points) was higher than those in the non-irAE-FMT mice (3.89 ± 1.17 points) and colitic-irAE-FMT-survival mice (3.67 ± 1.03 points) (Fig. 2C). The mean IHC scores of irAE-FMT-Sac. mouse from high to low were CD8 3.8 ± 1.3 points, CD4 2.0 ± 1.9 points, and CD20 1.1 ± 1.3 points (Fig. 2D), which also supported the occurrence of immune-related colitis. Figure 1. The gut microbiotas of patients with colitic and non-colitic type irAEs. Figure 2. Comparison of colitis in colitic-irAE-FMT and non-irAE-FMT mice. Conclusion Gut microbiota might play important role in the development of immune-related colitis, possibly by modulating metabolic pathways.

Effects of Prebiotic Fructooligosaccharides on Susceptibility to Dextran Sodium Sulfate‐Induced Colitis

Inflammatory bowel disease (IBD) is a chronic intestinal disease that includes Crohn’s disease and ulcerative colitis. Previous studies have found alterations in the microbiome in IBD and in animal models of IBD, underscoring the role of the intestinal microbiota in IBD pathogenesis. Prebiotics are molecules in foods, such as fructooligosaccharides and other soluble fiber molecules, that support the growth or activity of beneficial probiotic microbes. Previous studies suggest that prebiotics can reduce symptoms in models of colitis. This study aimed to determine whether pretreatment with 1% short‐chain fructooligosacchardies (FOS) for 1 week, followed by 8 days of 3% DSS administration with continued FOS treatment, altered the severity of disease in C57Bl/6 mice. Clinical signs of colitis, including weight loss, fecal occult blood, and fecal consistency, were monitored daily during the DSS treatment period and the daily disease activity index was calculated. At the end of the experiment, samples were collected for histological scoring, and for RNA isolation and analysis of colonic pro‐inflammatory cytokine expression by RT‐PCR. Through the 8 days of DSS treatment, the disease activity index increased in both DSS‐treated and FOS/DSS‐treated mice compared to control non‐colitic mice, but was not significantly different between the two colitic groups. In addition, colon wet weight, colon length, and histological colitis scores were similar in colitic mice treated with FOS compared to colitic mice without FOS treatment. Colonic claudin mRNA expression was lower in DSS‐treated mice than control mice, but was not significantly altered by FOS treatment. These data suggest that treatment with fructooligosaccharides did not significantly alter susceptibility to DSS‐induced colitis.

TNFAIP3 DRIVES COLITIS THROUGH DEATH CELL AND TNFα PRODUCTION

Abstract IBD is characterized by inflammation involving a complex interplay between innate and adaptive immunity, non-immune cells, and intestinal microbes. To understand the contributions of innate immunity to inflammation during colitis we have developed a chronic model of innate immune-mediated colitis wherein RAG1-/- mice are crossed with mice expressing TNFAIP3 in intestinal epithelial cells (villin-TNFAIP3 mice). These villin-TNFAIP3 x RAG1-/- (TRAG) mice develop early onset, 100% penetrant, chronic colitis driven by gut microbes. To understand the inflammatory signals that lead to innate colitis in this model, we crossed TRAG mice with TNFα-/- mice (FRAG mice) and compared the severity of colitis in TRAG vs. FRAG mice. In addition, we characterized TNFα-producing myeloid populations from the lamina propria of TRAG mice. Finally, we assessed the expression and localization of proteins involved in cell death pathways, to unravel the mechanisms driving innate-immune mediated colitis. Our results show that, compared to RAG1-/- mice, TRAG mice have significantly increased numbers of lamina propria leukocytes, including increased numbers of neutrophils, inflammatory monocytes, macrophages, dendritic cells, and innate lymphoid cells. TRAG mice lacking TNFα (FRAG mice) had significantly lower numbers of all these leukocyte subsets. Consistent with this, FRAG mice had significantly lower histological colitis scores, compared to TRAG mice. Inflammatory monocytes, monocytes, macrophages, and neutrophils were found to be the main sources of TNFα production, while TNFα production was null or minimal in dendritic cells, natural killer cells, ILC1, ILC3 and IC2. Macrophages and inflammatory monocytes in TRAG mice were characterized by the expression of iNOS, whereas macrophages and monocytes of FRAG and RAG1-/- mice were notably marked by Arginase1 expression. Localization of active caspase3, phosphor-MLKL and TUNEL positive cells indicated extensive epithelial crypt cell death in TRAG mice that was markedly suppressed in FRAG mice. Together our results show that TNFα drives innate immune mediated colitis, potentially through induction of IEC necroptosis. TNFAIP3 is well known as a negative regulator of receptor-mediated NFκB and MAPK activation and therefore attempts to increase TNFAIP3 expression are considered promising avenues for prevention of inflammation. The present study, indicating that intestinal epithelial cell expression of TNFAIP3 drives TNFα-induced IEC death and innate colitis, highlights potential tissue-specific roles for TNFAIP3 that should be considered in the paradigm of TNFAIP3 as a target for prevention of inflammation.

AUPHOS, A “FIRST-IN CLASS“ ORAL AGENT FOR CORRECTING METABOLIC DYSFUNCTION IN IBD

Abstract BACKGROUND Mucosal repair is the goal of medical therapy in IBD. Prospective inception cohort pediatric studies suggest that suppression of mitochondrial genes lead to unfavorable clinical outcomes in ulcerative colitis (UC) and Crohn’s disease (CD). We posit that the inability to restore epithelial mitochondrial respiration impairs ulcer healing in IBD. In the current study, we tested whether a novel compound (AuPhos) that improves mitochondrial function promotes ulcer healing in IBD. METHODS Biodistribution and pharmacokinectic (PK) studies were performed (6h, 12h, 24h) after single oral dose (25mg/kg) of AuPhos using C57/BL/6 (WT) mice. Mitochondrial uptake of AuPhos was determined by measuring gold content in normal colonocytes (NCM460) using graphite furnace atomic absorption spectroscopy. Oxygen consumption rate (OCR) in isolated crypt-IECs from AuPhos-fed WT mice were examined using high-resolution respirometry. The effect of AuPhos in colitis was tested in DSS (2%; 7d) WT (B6) mice. Disease activity index (DAI) (weight loss, diarrhea, and hematochezia), intestinal permeability (FITC-dextran), histological scoring and the frequency of fissioning crypts were determined throughout the 21d time course. Tissue mRNA levels for mitochondrial enzyme, cytokine, chemokine and intestinal stem cell (ISC) marker genes were assessed by RT-qPCR. RESULTS Biodistribution and PK studies revealed that higher levels of orally administered AuPhos in small intestine and colon tissue, with limited systemic absorption. AuPhos displayed a dose-dependent mitochondrial uptake in IEC where respirometry showed >30% increase in OCR after oral dosing in vivo. AuPhos treatment decreased DAI (**; p<0.01), histologic colitis scores D11-15 (*; p<0.05) and FITC-dextran permeability in DSS colitis mice. Notably, AuPhos increased fissioning crypt numbers near healing ulcers in DSS-colitis mice (**; p<0.01) while it reduced mRNA for pro-inflammatory cytokines/chemokines (IL-1β, IL-6, IFN-γ, IP10). AuPhos induced mRNA for ISC markers [Lgr4 (*; p<0.05), Lgr5, Lrig1 (***; p<0.001)] and mitochondrial complexes [mtCO1 (**; p<0.01) and COX2 (***; p<0.001)]. These findings suggest that AuPhos-induced mitochondrial respiration drives transcriptomic regulation of IEC genes involved in colitis ulcer healing. CONCLUSION Our data suggests that AuPhos compound improves ulcer healing under acute colitis conditions by increasing mucosal OxPHOS metabolism. Specifically, we find that AuPhos increases mitochondrial respiration-induced crypt fissioning and ulcer healing associated with reduced mucosal inflammation and increased barrier integrity. Overall, AuPhos may be an important “first-in class” oral therapeutic for correcting the metabolic dysfunction central to IBD pathogenesis.

Successful Manipulation of the Gut Microbiome to Treat Spontaneous and Induced Murine Models of Colitis.

There is clinical interest in the sustainability or otherwise of prebiotic, microbial, and antibiotic treatments to both prevent and treat inflammatory bowel diseases. This study examined the role of antibiotic manipulation of the gut microbiome to treat spontaneous and induced murine models of colitis. Symptomatic, histological, molecular, and microbial ecology and bioinformatic readouts were used to study the effect of a 10-day antibiotic cocktail and then follow-up over 2 months in the spontaneous Winnie colitis mouse preclinical model of ulcerative colitis and also the indirect antibiotic and Winnie microbiotic gavage effects in an acute dextran sodium sulfate-induced colitis model in wild-type mice. The antibiotics elicited a striking reduction in both colitis symptoms and blinded histological colitis scores, together with a convergence of the microbial taxonomy of the spontaneous colitis and wild-type control mice, toward a taxonomic phenotype usually considered to be dysbiotic. The improvement in colitis was sustained over the following 8 weeks although the microbial taxonomy changed. Invitro, fecal waters from the antibiotic-treated colitis and wild-type mice suppressed the inflammatory tenor of colonic epithelial cells, and gavaged cecal slurries from these mice moderated the acute induced colitis. The results clearly show the possibility of a sustained remission of colitis by microbial manipulation, which is relevant to clinical management of inflammatory bowel diseases. The beneficial effects appeared to depend on the microbial metabolome rather than its taxonomy.

Pro-Resolving Factors Released by Macrophages After Efferocytosis Promote Mucosal Wound Healing in Inflammatory Bowel Disease

Nonresolving inflammation is a critical driver of several chronic inflammatory diseases, including inflammatory bowel diseases (IBD). This unresolved inflammation may result from the persistence of an initiating stimulus or from the alteration of the resolution phase of inflammation. Elimination of apoptotic cells by macrophages (a process called efferocytosis) is a critical step in the resolution phase of inflammation. Efferocytosis participates in macrophage reprogramming and favors the release of numerous pro-resolving factors. These pro-resolving factors exert therapeutic effects in experimental autoimmune arthritis. Here, we propose to evaluate the efficacy of pro-resolving factors produced by macrophages after efferocytosis, a secretome called SuperMApo, in two IBD models, namely dextran sodium sulfate (DSS)-induced and T cell transfer-induced colitis. Reintroducing these pro-resolving factors was sufficient to decrease clinical, endoscopic and histological colitis scores in ongoing naive T cell-transfer-induced colitis and in DSS-induced colitis. Mouse primary fibroblasts isolated from the colon demonstrated enhanced healing properties in the presence of SuperMApo, as attested by their increased migratory, proliferative and contractive properties. This was confirmed by the use of human fibroblasts isolated from patients with IBD. Exposure of an intestinal epithelial cell (IEC) line to these pro-resolving factors increased their proliferative properties and IEC acquired the capacity to capture apoptotic cells. The improvement of wound healing properties induced by SuperMApo was confirmed in vivo in a biopsy forceps-wound colonic mucosa model. Further in vivo analysis in naive T cell transfer-induced colitis model demonstrated an improvement of intestinal barrier permeability after administration of SuperMApo, an intestinal cell proliferation and an increase of α-SMA expression by fibroblasts, as well as a reduction of the transcript coding for fibronectin (Fn1). Finally, we identified TGF-β, IGF-I and VEGF among SuperMApo as necessary to favor mucosal healing and confirmed their role both in vitro (using neutralizing antibodies) and in vivo by depleting these factors from efferocytic macrophage secretome using antibody-coated microbeads. These growth factors only explained some of the beneficial effects induced by factors released by efferocytic macrophages. Overall, the administration of pro-resolving factors released by efferocytic macrophages limits intestinal inflammation and enhance tissue repair, which represents an innovative treatment of IBD.

Gum Arabic Supplementation Suppresses Colonic Fibrosis After Acute Colitis by Reducing Transforming Growth Factor β1 Expression.

Ulcerative colitis is a chronic inflammation of the colonic mucosa. Gum Arabic (GA) has been reported to exert anti-inflammatory and antifibrotic activity. This study aimed to evaluate the effect of GA on disease activity in an experimental model of colitis. Dextran sodium sulfate (DSS) was used to induce colitis in C57BL/6 mice and the animals were then switched to normal drinking water to monitor recovery. Mice received 140 g/L GA before (pre-GA group) or after (post-GA group) induction of colitis. Disease activity and recovery were assessed by changes in body weight, disease activity index (DAI), and histological assessment. Gene expression of proinflammatory, anti-inflammatory, and fibrotic markers was measured in colonic tissues. Mice in the pre-GA group showed an increase in body weight, with no differences in DAI scores, during the recovery phase and had lower histological colitis scores than mice in the post-GA group, which showed higher DAI and histological scores during the recovery phase. During the recovery phase, mice in the pre-GA group showed increased expression of proinflammatory markers, while gene expression of the fibrotic markers, transforming growth factor β1 (TGFβ1) and procollagen I, was reduced. The reduced fibrotic marker expression was associated with reduced collagen staining and increased epithelial cell proliferation. Administration of GA had protective and alleviative effects on the severity of DSS-induced colitis, with a reduction in colonic fibrosis and TGFβ1 expression. These data warrant further in vitro and in vivo investigations on the effect of GA on fibroblast activity.

Energy Drink Administration Ameliorates Intestinal Epithelial Barrier Defects and Reduces Acute DSS Colitis.

The rise in the prevalence of inflammatory bowel diseases in the past decades coincides with changes in nutritional habits, such as adaptation of a Western diet. However, it is largely unknown how certain nutritional habits, such as energy drink consumption, affect intestinal inflammation. Here, we assessed the effect of energy drink supplementation on the development of intestinal inflammation in vitro and in vivo. HT-29 and T84 intestinal epithelial cells and THP-1 monocytic cells were treated with IFNγ in presence or absence of different concentrations of an energy drink. Colitis was induced in C57BL/6 mice by addition of dextran sodium sulfate (DSS) to drinking water with or without supplementation of the energy drink. Energy drink supplementation caused a dose-dependent decrease in IFNγ-induced epithelial barrier permeability, which was accompanied by upregulation of the pore-forming protein claudin-2. Administration of the energy drink reduced secretion of the pro-inflammatory cytokines interleukin-6 and tumor necrosis factor-α from HT-29, T84, and THP-1 cells. In vivo, energy drink administration reduced clinical symptoms of DSS-induced colitis and epithelial barrier permeability. Endoscopic and histologic colitis scores and expression of pro-inflammatory cytokines were significantly reduced by energy drink co-administration. Energy drink consumption seems to exert an unexpected anti-inflammatory effect in vitro and in vivo in our experimental setting. However, our experimental approach focuses on intestinal inflammation and neglects additional effects of energy drink consumption on the body (eg, on metabolism or sleep). Therefore, the translation of our findings into the human situation must be taken with caution.

One‐Pot Synthesis of pH‐Responsive Eudragit‐Mesoporous Silica Nanocomposites Enable Colonic Delivery of Glucocorticoids for the Treatment of Inflammatory Bowel Disease

AbstractOral glucocorticoids are backbones for the acute management of inflammatory bowel disease (IBD). However, the clinical effectiveness of conventional oral dosage forms of glucocorticoids is hindered by their low delivery efficiency and systemic side effects. To overcome this problem, a smart drug delivery system with high loading capacity and colonic release by coating functionalized mesoporous silica nanoparticles (MSNs) with a pH‐responsive polymer Eudragit S100 is proposed. In vitro dissolution tests show that Eudragit‐coated MSNs can limit the burst release of loaded prednisolone and budesonide in the gastric environment with more than 60% of the drugs released only at colonic pH (i.e., pH ≥ 7). In vivo therapeutic efficacy of budesonide‐loaded nanoparticles is tested in a murine model of dextran sodium sulfate‐induced colitis. An oral budesonide dose of 0.2 mg kg−1 nanoparticles with Eudragit coating improves the disease activity index compared to other groups. Interestingly, both coated and uncoated nanoparticles show pathological improvements demonstrated by similar levels of histological colitis score. However, coated nanoparticles significantly decrease mRNA expression of the cytokines (Il‐1β, Il‐17, and Il‐10) particularly in proximal colon, indicating colonic delivery. Overall, this study demonstrates the effectiveness of a simple method to fabricate targeted nanomedicine for the treatment of IBD.

Serum-Free Medium Enhances the Therapeutic Effects of Umbilical Cord Mesenchymal Stromal Cells on a Murine Model for Acute Colitis.

The usage of animal serum may ultimately prevent the application of ex vivo cultured mesenchymal stromal cells (MSCs) in a clinical setting due to safety concerns and batch-to-batch variability. Increasing regulatory pressure to limit use of animal serum has been issued and serum-free, xeno-free, and chemically defined media (S&XFM-CD) is encouraged to replace serum-containing media (SCM) in the stem cell preparation process. We previously developed a S&XFM-CD for the expansion of umbilical cord-derived MSCs (UCMSCs). Different culture conditions affect the function of MSCs, which may further affect the therapeutic efficiency and mechanisms of action. In this study, we compared the therapeutic effect and mechanism of UCMSCs in S&XFM-CD (UCMSCS&XFM−CD) in experimental colitis with those in SCM (UCMSCSCM). UCMSCS&XFM−CD exhibited better therapeutic effects than UCMSCSCM by body weight, disease activity index, and histological colitis score. UCMSCS&XFM−CD or UCMSCSCM migrated to the inflammation site of injured colon, but exhibited low levels of recruitment and persistence. Systemic depletion of endogenous macrophages impaired the therapeutic effects of UCMSCSCM and UCMSCS&XFM−CD. Furthermore, UCMSCS&XFM−CD more markedly promoted intestinal macrophage polarisation from M1 to M2 phenotype to produce higher levels of IL-10 and lower levels of TNF-α in colon tissue than UCMSCSCM, while a higher level of IL-4 was produced in UCMSCSCM-treated group. UCMSCS&XFM−CD cocultured with RAW264.7 cells in a transwell system promoted the release of TSG-6 and IL-6, whereas UCMSCSCM increased PGE2 levels. Taken together, we demonstrated that UCMSCs in S&XFM-CD exhibited improved therapeutic effects with altered cytokine secretion in an experimental acute colitis model.

Immunosuppressive Effect of Exosomes from Mesenchymal Stromal Cells in Defined Medium on Experimental Colitis.

Background and ObjectivesThe exosomes released by mesenchymal stromal cells (MSCs) in classical FBS-containing media have been demonstrated as an alternative, cell-free therapy in various diseases including inflammatory bowel disease (IBD). It has been found that the function of exosomes is affected by culture condition. We previously developed a serum-free, xeno-free and chemically defined medium, and umbilical cord-derived MSCs in this medium retained the immunosuppressive capability.MethodsIn this study, we evaluated the immunosuppressive function of exosomes from MSCs (MSC-Exo) in defined medium and their therapeutic effect on treating colitis.Results and ConclusionsIn vitro studies indicated that MSC-Exo reduced the concentration of pro-inflammatory cytokines IFN-γ, TNF-α and IL-1β, and increased the secretion of anti-inflammatory cytokines TGF-β1 and IL-10, but no significant change of inhibitory effect on peripheral blood mononuclear cells proliferation was shown. In vivo experimental colitis showed that administration of MSC-Exo was able to significantly ameliorate the disease activity index score, weight loss, colon shortening, and the histological colitis score through up-regulation anti-inflammatory responses and down-regulation of inflammatory responses. Moreover, the use of MSC-Exo (200 μg) led to an improved therapeutic efficacy when compared with MSCs at a dose of 1×106 cells. Our findings indicate that the exosomes from MSCs in defined medium possess a certain degree of immunosuppressive effect in vitro and exhibit a therapeutic capability in a mouse model of DSS-induced colitis through suppressing inflammation mechanism.

Preconditioning Enhances the Therapeutic Effects of Mesenchymal Stem Cells on Colitis Through PGE2-Mediated T-Cell Modulation

Mesenchymal stem cell (MSC)-based cell therapy has been demonstrated as a promising strategy in the treatment of inflammatory bowel disease (IBD), which is considered an immune disease. While the exact mechanisms underlying the therapeutic effect of MSCs are still unclear, MSCs display anti-inflammatory and immunomodulatory effects by interacting with various immunoregulatory cells. Our previous studies have shown that MSCs can be preconditioned and deconditioned with enhanced cell survival, differentiation and migration. In this study, we evaluated the effect of preconditioning on the immunoregulatory function of human umbilical cord-derived MSCs (hUCMSCs) and their therapeutic effect on treating IBD. Our results show that intraperitoneal administration of deconditioned hUCMSCs (De-hUCMSCs) reduces the disease activity index (DAI), histological colitis score and destruction of the epithelial barrier, and increases the body weight recovery more intensively than that of un-manipulated hUCMSCs. In addition, De-hUCMSCs but not hUCMSCs elicit anti-apoptotic effects via induction of the ERK pathway during the early stage of IBD development. In vitro co-culture studies indicate that De-hUCMSCs suppress T-cell proliferation and activation more markedly than hUCMSCs. Moreover, De-hUCMSCs block the induction of inflammatory cytokines such as tumor necrosis factor (TNF)α and interleukin (IL)-2, while promoting the secretion of the anti-inflammatory cytokine IL-10 in T-cells. Mechanically, we find that prostaglandin E2 (PGE2) secretion is significantly increased in De-hUCMSCs, the suppression of which dramatically abrogates the inhibitory effect of De-hUCMSCs on T-cell activation, implying that the crosstalk between De-hUCMSCs and T-cells is mediated by PGE2. Together, we have demonstrated that preconditioning enhances the immunosuppressive and therapeutic effects of hUCMSCs on treating IBD via increased secretion of PGE2.

Pre-clinical and translational pharmacology of a human interleukin-22 IgG fusion protein for potential treatment of infectious or inflammatory diseases

Interleukin (IL)-22 plays protective roles in infections and in inflammatory diseases that have been linked to its meditation of innate immunity via multiple mechanisms. IL-22 binds specifically to its heterodimeric receptor, which is expressed on a variety of epithelial tissues. UTTR1147A is a recombinant fusion protein that links the human cytokine IL-22 with the Fc portion of human immunoglobulin (Ig) G4. Here, we report extensive in vitro and in vivo nonclinical studies that were conducted to characterize the pharmacological activity of UTTR1147A. The in vitro activity and potency of UTTR1147A were analyzed using primary human hepatocytes and human colonic epithelial cell lines. Assessment of in vivo efficacy was performed in a mouse colitis model and by measuring relevant pharmacodynamic biomarkers, including antimicrobial peptides REG3A/β, serum amyloid protein A (SAA) and lipopolysaccharide binding protein (LBP). The pharmacokinetic and pharmacodynamic characteristics of UTTR1147A were assessed in healthy mice, rats and cynomolgus monkeys. UTTR1147A induced STAT3 activation through binding to IL-22 receptor expressed in primary human hepatocytes and human colon cell lines. In both, activation occurred in a concentration-dependent manner with similar potencies. In the mouse colitis model, murine IL-22Fc- (muIL-22Fc) treated groups at doses of 1.25 μg and above had statistically lower average histologic colitis scores compared to the control treated group. Administration of muIL-22Fc or UTTR1147A was associated with a dose-dependent induction of PD markers REG3β and SAA in rodents as well as REG3A, SAA and LBP in cynomolgus monkeys. The combined data confirm pharmacological activity of IL-22Fc and support potential regenerative and protective mechanisms in epithelial tissues.

Nanoparticle curcumin ameliorates experimental colitis via modulation of gut microbiota and induction of regulatory T cells.

Background and AimsCurcumin is a hydrophobic polyphenol derived from turmeric, a traditional Indian spice. Curcumin exhibits various biological functions, but its clinical application is limited due to its poor absorbability after oral administration. A newly developed nanoparticle curcumin shows improved absorbability in vivo. In this study, we examined the effects of nanoparticle curcumin (named Theracurmin) on experimental colitis in mice.MethodsBALB/c mice were fed with 3% dextran sulfate sodium (DSS) in water. Mucosal cytokine expression and lymphocyte subpopulation were analyzed by real-time PCR and flow cytometry, respectively. The profile of the gut microbiota was analyzed by real-time PCR.ResultsTreatment with nanoparticle curcumin significantly attenuated body weight loss, disease activity index, histological colitis score and significantly improved mucosal permeability. Immunoblot analysis showed that NF-κB activation in colonic epithelial cells was significantly suppressed by treatment with nanoparticle curcumin. Mucosal mRNA expression of inflammatory mediators was significantly suppressed by treatment with nanoparticle curcumin. Treatment with nanoparticle curcumin increased the abundance of butyrate-producing bacteria and fecal butyrate level. This was accompanied by increased expansion of CD4+ Foxp3+ regulatory T cells and CD103+ CD8α− regulatory dendritic cells in the colonic mucosa.ConclusionsTreatment with nanoparticle curcumin suppressed the development of DSS-induced colitis potentially via modulation of gut microbial structure. These responses were associated with induction of mucosal immune cells with regulatory properties. Nanoparticle curcumin is one of the promising candidates as a therapeutic option for the treatment of IBD.

Umbilical cord-derived mesenchymal stem cell extracts reduce colitis in mice by re-polarizing intestinal macrophages

Human umbilical cord mesenchymal stem cells (hUC-MSCs), originating in Wharton’s jelly, are multipotent stem cells that home to damaged tissues and can modulate the immune system. We examined whether administering extracts of MSCs (MSC-Ex) instead of MSCs could augment the beneficial effects of MSC therapy by overcoming the low homing efficiency of MSCs systemically administered in inflammatory bowel diseases (IBD). Dextran sodium sulfate-induced colitis model was established in C57BL/6 mice, and MSC-Ex was administered intraperitoneally. MSC-Ex reduced colitis, disease activity index (DAI), and histological colitis scores, and increased the body weight. Treatment with MSC-Ex completely blocked the induction of inflammatory cytokines, which were strongly detected in mice with colitis. MSC-Ex shifted the macrophage functional phenotype from M1 to M2 by decreasing the levels of MCP1, CXCL9, and iNOS, but increasing the levels of IL-10, LIGHT, CCL1, and Arg-1. MSC-Ex recovered the destruction of the epithelial barrier in the differentiated Caco-2 cells in vitro. Treatment with MSC-Ex was more potent than that with MSC in reducing DAI, the histological score, and nitrite levels. These data strongly support that MSC-Ex treatment can be a potent approach to overcome severe refractory IBD.