Signs Of Colitis Research Articles

Point-of-care ultrasound of the inflammatory bowel disease

Background. The widespread use of portable ultrasound scanners has advanced the concept of ultrasound diagnosis (POCUS), namely «ultrasound examination (US) is performed at the bedside and is interpreted directly by a physician». Pocus is not a substitute for complex ultrasound, but rather allows the ultrasound doctor to quickly access clinical images for rapid diagnosis and effective examination and treatment of patients. Purpose – the work to identify ultrasound signs of inflammatory bowel disease (IBD) using POCUS. Materials and Methods. 70 patients aged 18 to 39 years (24 men and 46 women, mean age – 30.3 ± 13.7 years). The first group of patients included 32 people with a morphologically confirmed CD diagnosis, the second group included 38 people with a morphologically confirmed UC diagnosis. The control group consisted of 2 8 patients with no clinical and laboratory data on gastrointestinal lesions. Results. It was shown that the ultrasound can assess the thickness of the intestinal wall with sensitivity – 90.3% and specificity – 87.1% and ROC – 0.882, differentiation of the wall layers, surrounding structures (omentum, mesentery, lymph nodes), as well as the localization of the affected intestinal segment. Color Doppler Mapping (CDM) method with a sensitivity of 86.5% and specificity of 81.5% and ROC of 0.852 allows not only to assume the presence of active inflammation in the wall of the affected intestinal segment, but also to monitor the dynamics of the process during treatment. Conclusion. In this work, the capabilities of POCUS for the diagnosis of IBD were evaluated. Correct and accurate interpretation of POCUS findings is not only an important diagnostic step, but also a complement to other radiation and endoscopic imaging techniques. The main advantage of POCUS over CT and MRI is its fast availability, low cost, and high level of safety. An experienced ultrasound doctor is needed to examine the gastrointestinal tract, so training with ultrasound doctors and mastering practical skills is key to ensuring the effective use of POCUS.

Anti-Inflammatory Effect of Dietary Pentadecanoic Fatty Acid Supplementation on Inflammatory Bowel Disease in SAMP1/YitFc Mice.

Dietary fats have been linked to the increasing incidence of chronic diseases, including inflammatory bowel diseases (IBD), namely, Crohn's disease (CD). This study investigated the impact of pentadecanoic acid (C15:0), a type of an odd-numbered chain saturated fatty acid, for its potential anti-inflammatory properties in different mouse models of experimental IBD using the SAMP1/YitFc (SAMP) mouse line (14- or 24-week-old), including chronic ileitis and DSS-induced colitis. To quantitively assess the effect of C:15, we tested two dosages of C:15 in selected experiments in comparison to control mice. Intestinal inflammation and intestinal permeability were used as primary outcomes. In ileitis, C:15 supplementation showed an anti-inflammatory effect in SAMP mice (e.g., a reduction in ileitis severity vs. control p < 0.0043), which was reproducible when mice were tested in the DSS model of colitis (e.g., reduced permeability vs. control p < 0.0006). Of relevance, even the short-term C:15 therapy prevented colitis in mice by maintaining body weight, decreasing inflammation, preserving gut integrity, and alleviating colitis signs. Collectively, the findings from both ileitis and colitis in SAMP mice indicate that C:15 may have therapeutic effects in the treatment of IBD (colitis in the short term). This promising effect has major translational potential for the alleviation of IBD in humans.

Cutaneous Application of Capsaicin Cream Reduces Clinical Signs of Experimental Colitis and Repairs Intestinal Barrier Integrity by Modulating the Gut Microbiota and Tight Junction Proteins.

Capsaicin, a pungent compound in chili peppers, is described as having potent anti-inflammatory, antioxidant, and antimicrobial properties. It is also described as a potential modulator of the immune system and intestinal microbiota. Oral or rectal administration of capsaicin has been studied to treat or prevent colitis. However, those vias are often not well accepted due to the burning sensation that capsaicin can cause. Our objective was to evaluate whether the application of capsaicin skin creams (0.075%) would be effective in improving inflammation and epithelial barrier function as well as the composition of the gut microbiota in a model of mild colitis induced by dextran sulfate sodium (1.5%). The results showed that the cutaneous application of capsaicin reversed weight loss and decreased colon shortening and diarrhea, all typical signs of colitis. There was also an improvement in the intestinal epithelial barrier, preserving proteins from tight junctions. We also evaluated the biodistribution of 99mtechnetium-radiolabeled capsaicin (99mTc-CAPS) applied to the back skin of the animals. We found significant concentrations of 99 mTc-Cap in the colon and small intestine after 2 and 4 h of administration. In addition, there was an increased expression of capsaicin receptor TRPV1 in the colon. Moreover, animals with colitis receiving cutaneous capsaicin presented a better short-chain fatty acid profile and increased levels of SIgA, suggesting increased microbiota diversity. In conclusion, our work opens avenues for further studies to better understand capsaicin's potential benefits and mechanisms in addressing colitis through cutaneous application.

Amelioration of Dextran Sodium Sulfate-Induced Colitis in Mice through Oral Administration of Palmitoylethanolamide.

Inflammatory bowel disease (IBD) is a group of chronic disorders characterized by pain, ulceration, and the inflammation of the gastrointestinal tract (GIT) and categorized into two major subtypes: ulcerative colitis (UC) and Crohn's disease. The inflammation in UC is typically restricted to the mucosal surface, beginning in the rectum and extending through the entire colon. UC patients typically show increased levels of pro-inflammatory cytokines, leading to intestinal epithelial apoptosis and mucosal inflammation, which impair barrier integrity. Chronic inflammation is associated with the rapid recruitment and inappropriate retention of leukocytes at the site of inflammation, further amplifying the inflammation. While UC can be managed using a number of treatments, these drugs are expensive and cause unwanted side effects. Therefore, a safe and effective treatment for UC patients is needed. Palmitoylethanolamide (PEA) is an endogenous fatty acid amide and an analog of the endocannabinoid anandamine. PEA administration has been found to normalize intestinal GIT motility and reduce injury in rodents and humans. In the current study, we examined the efficacy of PEA encapsulated in phytosomes following oral administration in experimental ulcerative colitis. Here, we showed that PEA at a human-equivalent dose of 123 mg/kg (OD or BID) attenuated DSS-induced experimental colitis as represented by the reduction in clinical signs of colitis, reduction in gross mucosal injury, and suppression of leukocyte recruitment at inflamed venules. These findings add to the growing body of data demonstrating the beneficial effects of PEA to control the acute phase of intestinal inflammation occurring during UC.

Colitis reduces active social engagement in mice and is ameliorated by supplementation with human microbiota members

Multiple neurological disorders are associated with gastrointestinal (GI) symptoms, including autism spectrum disorder (ASD). However, it is unclear whether GI distress itself can modify aspects of behavior. Here, we show that mice that experience repeated colitis have impaired active social engagement, as measured by interactions with a foreign mouse, even though signs of colitis were no longer present. We then tested the hypothesis that individuals with ASD harbor a microbiota that might differentially influence GI health by performing microbiota transplantation studies into male germfree animals, followed by induction of colitis. Animals that harbor a microbiota from ASD individuals have worsened gut phenotypes when compared to animals colonized with microbiotas from familial neurotypical (NT) controls. We identify the enrichment of Blautia species in all familial NT controls and observe an association between elevated abundance of Bacteroides uniformis and reductions in intestinal injury. Oral treatment with either of these microbes reduces colon injury in mice. Finally, provision of a Blautia isolate from a NT control ameliorates gut injury-associated active social engagement in mice. Collectively, our data demonstrate that past intestinal distress is associated with changes in active social behavior in mice that can be ameliorated by supplementation of members of the human microbiota.

The emergence of inflammatory microglia during gut inflammation is not affected by FFAR2 expression in intestinal epithelial cells or peripheral myeloid cells

Gut inflammation can trigger neuroinflammation and is linked to mood disorders. Microbiota-derived short-chain fatty acids (SCFAs) can modulate microglia, yet the mechanism remains elusive. Since microglia do not express free-fatty acid receptor (FFAR)2, but intestinal epithelial cells (IEC) and peripheral myeloid cells do, we hypothesized that SCFA-mediated FFAR2 activation within the gut or peripheral myeloid cells may impact microglia inflammation. To test this hypothesis, we developed a tamoxifen-inducible conditional knockout mouse model targeting FFAR2 exclusively on IEC and induced intestinal inflammation with dextran sodium sulfate (DSS), a well-established colitis model. Given FFAR2′s high expression in myeloid cells, we also investigated its role by selectively deleting it in these populations of cells. In an initial study, male and female wild-type mice received 0 or 2% DSS for 5d and microglia were isolated 3d later to assess inflammatory status. DSS induced intestinal inflammation and upregulated inflammatory gene expression in microglia, indicating inflammatory signaling via the gut-brain axis. Despite the lack of significant effects of sex in the intestinal phenotype, male mice showed higher microglial inflammatory response than females. Subsequent studies using FFAR2 knockout models revealed that FFAR2 expression in IECs or immune myeloid cells did not affect DSS-induced colonic pathology (i.e. clinical and histological scores and colon length), or colonic expression of inflammatory genes. However, FFAR2 knockout led to an upregulation of several microglial inflammatory genes in control mice and downregulation in DSS-treated mice, suggesting that FFAR2 may constrain neuroinflammatory gene expression under healthy homeostatic conditions but may permit it during intestinal inflammation. No interactions with sex were observed, suggesting sex does not play a role on FFAR2 potential function in gut-brain communication in the context of colitis. To evaluate the role of FFAR2 activated by microbiota-derived SCFAs, we employed the same knockout and DSS models adding fermentable dietary fiber (0 or 2.5% inulin for 8 wks). Despite no genotype or fiber main effects, contrary to our hypothesis, inulin feeding augmented DSS-induced inflammation and signs of colitis, suggesting context-dependent effects of fiber. These findings highlight microglial involvement in colitis-associated neuroinflammation and advance our understanding of FFAR2′s role in the gut-brain axis. Although not integral, we observed that the role of FFAR2 differs between homeostatic and inflammatory conditions, underscoring the need to consider different inflammatory conditions and disease contexts when investigating the role of FFAR2 and SCFAs in the gut-brain axis.

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

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

TNF IS REQUIRED FOR SPONTANEOUS INNATE COLITIS IN MICE LACKING ADAPTIVE IMMUNITY

Abstract BACKGROUND Colitis involves excessive inflammation driven by the reciprocal interaction of innate and adaptive immune cells. To better understand how innate immunity contributes to colitis, we developed a spontaneous innate model of colitis that is highly penetrant, early onset, and driven by microbes. TNF is a cytokine produced predominantly by T cells but also by innate and non-immune cells and contributes to IBD in many patients. We therefore examined the role of TNF in innate immune mediated colitis. METHODOLOGY We developed a 100% penetrant mouse model of colitis by crossing villin transgenic expression of tnfaip3 (villin-tnfaip3) to rag1 null mice (rag1-/-), designated as TRAG mice (villin-tnfaip3 x rag1-/-). TRAG mice are characterized by inflammation of the colon in the absence of T and B cells. We crossed TRAG mice with tnfa-/- mice (tnfa-/- x TRAG) to elucidate the role of TNF in this model. The histopathological score of disease was evaluated by H&amp;E, and the innate immune populations characterized by multi-color flow cytometry. Apoptosis, necrosis, and cell death were evaluated histologically by localizing cleaved caspase-3, phosho-MLKL and TUNEL positive cells. Secretion of cytokines from intestinal tissue in culture was quantified by ELISA. RESULTS TRAG mice develop early-onset colitis that is driven by microbes but is not transmissible to rag1-/- littermates. TRAG mice showed histological signs of colitis and a high infiltration of leukocytes in the intestinal mucosa without concurrent systemic inflammation. This colitis was not observed in tnfa-/- x TRAG mice. TRAG mice exhibited a pro-inflammatory cytokine signature with elevated secretion of IL1a and IL1b but not IL-18 or IL-33, which was not observed in mucosa from tnfa-/- x TRAG mice. LPLs from TRAG colons indicated TNF production by inflammatory monocytes, monocytes, and neutrophils. Monocytes and macrophages from the TRAG mouse mucosa, but not the tnfa-/- x TRAG mucosa, showed an M1 profile defined by elevated iNOS and decreased arginase. Increased crypt cell death was evident in TRAG colons, and this was significantly diminished in the crypts of tnfa-/- x TRAG colons. Early aggressive treatment of TRAG mice with anti-TNF antibody, but not anti-IL1a antibody, prevented colitis in TRAG mice. CONCLUSIONS TNF drives innate colitis featuring increased infiltration of mucosal leukocytes, increased secretion of IL1a and IL1b, skewing of macrophages to an M1 profile, and increased cell death in colonic crypts. Even in the absence of T cell derived cytokines, including TNF, innate sources of TNF are sufficient to drive colitis and early use of anti-TNF therapy is effective against this innate form of colitis. We are currently investigating the signals and forms of cell death that are driven by TNF in this model.

The structure of gastrointestinal tract pathology in patients receiving hemodialysis treatment

BACKGROUND. Hemodialysis patients are characterized by a wide range of concomitant diseases, including cardiovascular, bone mineral, nutritional, cognitive, various metabolic disorders and anemia. Meanwhile, gastrointestinal tract disorders in these patients remains largely unexplored. Patients receiving treatment with programmed hemodialysis are characterized by a wide range of concomitant diseases, including cardiovascular, bone mineral, nutritional, cognitive, various metabolic disorders and anemia. Meanwhile, the pathology of the gastrointestinal tract in this category of patients remains largely unexplored.AIM: to investigate the structure of digestive diseases in patients receiving hemodialysis treatment.PATIENTS AND METHODS. This study included 180 hemodialysis patients. The median age was 60[47;68] years. Gastrointestinal Symptoms Questionnaire (GSQ) was used to evaluate gastrointestinal symptoms over the last month. The results of abdomen ultrasound, gastroscopy, colonoscopy, and complex laboratory examination were also analyzed.RESULTS. The overall prevalence of gastrointestinal symptoms was 77.2 % (139/180). The most frequent complaints were constipation (46.8 %) and abdominal pain (41 %). The most common stool frequency was one bowel action per day. The third, fourth, fifth type of stool according to the Bristol Stool Form Scale were noted by the majority of participants. Abdominal ultrasound revealed diffuse liver changes in 115 (63.9 %), signs of cirrhosis – in 7(3.9 %) patients. Ultrasound pathology of the gallbladder was represented by anomalies of its shape in 11.1 %, signs of chronic cholecystitis – in 10 %, stones (sludge) – in 7.2 %, polyps – in 2.2 % of patients. Diffuse changes in pancreatic parenchyma, steatosis, pseudocysts and dilatation of the main pancreatic duct were diagnosed respectively in 39(21,7 %), 21(11,7 %), 10(5,6 %) and 3(1.7 %) hemodialysis patients. According to 154 gastroscopies, the most common endoscopic finding in the stomach was chronic gastritis, detected in 86(55.8 %) of the subjects. Erosive gastritis was diagnosed in 22(14.3 %), gastric ulcer – in 3(2.0 %) patients. Endoscopic duodenal pathology was represented by erythematous duodenitis in 53(34.4 %), erosive duodenitis in 15(9.7 %), ulcer in 2(1.3 %), duodenal bulb abnormalities in 23(14.9 %) patients. Combined gastric and duodenal lesions were found in 88(57.1 %) patients. Сolonoscopy was performed in 56 patients, of whom 15 (26.8 %) had signs of colitis (mainly sigmoiditis), 2(3.6 %) – diverticulitis, 10(17.9 %) – diverticulosis, 12(21.4 %) – colon polyps, 8(14.3 %) – angiodysplasia mucosa, in 3(5.4 %) – dolichocolon. Despite the abundance of gastrointestinal symptoms and instrumental findings, no significant deviations in laboratory parameters (including an increase in AST, ALT, total bilirubin, amylase, lipase) were found.CONCLUSION. Hemodialysis patients are characterized by a high prevalence of gastrointestinal symptoms and various pathological changes in the gastrointestinal tract, the diagnosis and treatment of which require an individual multidisciplinary approach.

The Anti-Inflammatory Effects of Adipose Tissue Mesenchymal Stem Cell Exosomes in a Mouse Model of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a group of chronic, relapsing inflammatory disorders that affect the gastrointestinal tract, with the primary subtypes being ulcerative colitis (UC) and Crohn’s disease (CD). We aimed to evaluate the therapeutic potential of extracellular vesicles released by adipose-tissue-derived mesenchymal stem cells, which we, in this manuscript, call “exosomes” (ASC-EXOs), in a mouse model of IBD. We specifically aimed to determine the effectiveness of different treatment protocols and compare the effects with that of anti-IL-12 p40 monoclonal antibody. The addition of dextran sulfate sodium (DSS) to drinking water induced multiple signs of IBD, including weight loss, soft stool, and bloody feces. ASC-EXOs given by either intraperitoneal (IP) or intravenous (IV) routes resulted in moderate improvement in these signs of IBD. IV ASC-EXOs resulted in significantly reduced body weight loss, improved histopathological scoring, and suppressed the disease activity index (DAI) compared to the IBD control group. Also, a reduction in PCR for pro-inflammatory cytokines was observed. IV ASC treatment resulted in dose-related reduction in IBD signs, including weight loss. An increasing number of injections with ASC-EXOs reduced histopathological scores as well as DAI. Co-administration of ASC-EXOs with anti-IL-12 p40 significantly decreased DAI scores in the ASC-EXO + anti-IL-12 p40 group. In conclusion, ASC-EXOs have potential as a therapeutic agent for IBD, but the route of administration, number of injections, and dosage need to be considered to optimize the effects of ASC-EXO treatment. This study also highlights the potential benefits of combination therapies of ASC-EXOs and anti-IL-12. Our findings pave the way for further studies to unravel the underlying therapeutic mechanisms of ASC-EXOs in IBD treatment.

Prophylactic Coloprotective Effect of Urtica dioica Leaves against Dextran Sulfate Sodium (DSS)-Induced Ulcerative Colitis in Rats.

Background and Objectives: Urtica dioica, a source of bioactive functional compounds, provides nutritional and gastrointestinal therapeutic benefits. This study attempted to investigate the prophylactic coloprotective action of an aqueous extract of Urtica dioica (AEUD) on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC). Materials and Methods: Phenolic compounds, total sugar, and mineral levels were determined in AEUD. Then, AEUD at different doses (50, 100, and 200 mg/kg, BW, p.o.) and mesalazine (MESA) as a standard treatment (100 mg/kg, BW, p.o.) were given orally for 21 days. Acute colitis was induced by administering drinking water with 5% (w/v) DSS for 7 days. Body weight variation, fecal occult blood, and stool consistency were determined daily. The severity of colitis was graded according to colon length, disease activity index (DAI), histological evaluations, and biochemical alterations. Rats orally administered DSS regularly developed clinical and macroscopic signs of colitis. Results: Due to its richness in phenolic and flavonoid compounds (247.65 ± 2.69 mg EAG/g MS and 34.08 ± 0.53 mg EQt/g MS, respectively), AEUD markedly ameliorated DAI, ulcer scores, colon length shortening, colonic histopathological changes, and hematological and biochemical modifications. Taken together, AEUD treatment notably (p < 0.01) suppressed DSS-induced UC by reducing oxidative stress via lowering MDA/H2O2 production and stimulating the effect of enzyme antioxidants as well as attenuating inflammation by decreasing CRP levels by 79.5% between the DSS and DSS + AEUD-50 groups compared to the MESA group (75.6%). Conclusions: AEUD was sufficient to exert a coloprotective effect that might be influenced by its bioactive compounds' anti-inflammatory and antioxidant capabilities.

Lactobacillus johnsonii N5 from heat stress-resistant pigs improves gut mucosal immunity and barrier in dextran sodium sulfate-induced colitis

Developing effective strategies to prevent diarrhea and associated-gut disorders in mammals has gained great significance. Owing to the many health benefits provided by the commensal microbiota of the intestinal tract, such as against environmental perturbation, we explored the host phenotype-associated microbes and their probiotic potential. Based on the observations that the chronic heat stress-exposed weaned piglets present as heat stress-susceptible (HS-SUS) or heat stress-resistant (HS-RES) individuals, we confirmed the phenotypic difference between the two on growth performance (P < 0.05), diarrhea index (P < 0.001), intestinal heat shock protein 70 (HSP70) regulation (P < 0.01), and inflammatory responses (P < 0.01). By comparing the gut microbiome using 16S rRNA gene sequencing and KEGG functional analysis, we found that Lactobacillus johnsonii exhibited significantly higher relative abundance in the HS-RES piglets than in the HS-SUS ones (P < 0.05). Further experiments using a mouse model for chemical-induced inflammation and intestinal injury demonstrated that oral administration of a representative L. johnsonii N5 (isolated from the HS-RES piglets) ameliorated the clinical and histological signs of colitis while suppressing intestinal pro-inflammatory cytokines TNF-α and IL-6 production (P < 0.05). We found that N5 treatment enhanced tight junction proteins ZO-1 and occludin and cytoprotective HSP70 levels under physiological condition and restored their mucosal expressions in colitis (P < 0.05). In support of the high production of the anti-inflammatory cytokine IL-10, N5 promoted the intestinal Peyer's patches MHCII+ and CD103+ dendritic cell populations (P < 0.05), increased the regulatory T (Treg) cell numbers (P < 0.05), and decreased the Th17 population and its IL-17a production under physiological condition and during colitis (P < 0.01). Our results shed light on understanding the interaction between commensal Lactobacillus and the host health, and provide L. johnsonii N5 as an alternative to antibiotics for preventing diarrhea and intestinal diseases.

Development of trans-Chalcone loaded pectin/casein biodegradable microcapsules: Efficacy improvement in the management of experimental colitis

Improved therapies for inflammatory bowel diseases are sorely needed. Novel therapeutic agents and the development of controlled release systems for targeted tissue delivery are interesting approaches to overcome these barriers. We investigated the activity of trans-chalcone (T) in acetic acid-induced colitis in mice and developed, characterized, and determined the therapeutic effect of pectin/casein polymer microcapsules containing T (MT) in a colitis mouse model. In vitro, compound release was achieved in simulated intestinal fluid but not in the simulated gastric fluid. In vivo, since T at the dose of 3 mg/kg but not 0.3 mg/kg ameliorated colitis, we next tested the effects of MT at 0.3 mg/kg (non-effective dose). MT, but not free T at 0.3 mg/kg, significantly improved colitis outcomes such as neutrophil recruitment, antioxidant capacity, cytokine production, and NF-kB activation. This translated into reduced macro and microscopic damage in the colon. T release from the microcapsules is mediated by a pH-dependent and pectinase-regulated mechanism that provide controlled and prolonged release of T. Moreover, MT lowered the required dose for T therapeutic effect, indicating that could be a suitable pharmaceutical approach to colitis treatment. This is the first demonstration that T or MT is effective at reducing the signs of colitis.

Anti-Inflammatory Activity of Black Soldier Fly Oil Associated with Modulation of TLR Signaling: A Metabolomic Approach

Dietary intervention in the treatment of ulcerative colitis involves, among other things, modifications in fatty acid content and/or profile. For example, replacing saturated long chain fatty acids with medium chain fatty acids (MCFAs) has been reported to ameliorate inflammation. The Black Soldier Fly Larvae’s (BSFL) oil is considered a sustainable dietary ingredient rich in the MCFA C12:0; however, its effect on inflammatory-related conditions has not been studied until now. Thus, the present study aimed to investigate the anti-inflammatory activity of BSFL oil in comparison to C12:0 using TLR4- or TLR2-activated THP-1 and J774A.1 cell lines and to assess its putative protective effect against dextran sulfate sodium (DSS)-induced acute colitis in mice. BSFL oil and C12:0 suppressed proinflammatory cytokines release in LPS-stimulated macrophages; however, only BSFL oil exerted anti-inflammatory activity in Pam3CSK4-stimulated macrophages. Transcriptome analysis provided insight into the possible role of BSFL oil in immunometabolism switch, involving mTOR signaling and an increase in PPAR target genes promoting fatty acid oxidation, exhibiting a discrepant mode of action compared to C12:0 treatment, which mainly affected cholesterol biosynthesis pathways. Additionally, we identified anti-inflammatory eicosanoids, oxylipins, and isoprenoids in the BSFL oil that may contribute to an orchestrated anti-inflammatory response. In vivo, a BSFL oil-enriched diet (20%) ameliorated the clinical signs of colitis, as indicated by improved body weight recovery, reduced colon shortening, reduced splenomegaly, and an earlier phase of secretory IgA response. These results indicate the novel beneficial use of BSFL oil as a modulator of inflammation.

Picroside III, an Active Ingredient of Picrorhiza scrophulariiflora, Ameliorates Experimental Colitis by Protecting Intestinal Barrier Integrity.

This study aims to explore the protective effects of Picroside III, an active ingredient of Picrorhiza scrophulariiflora, on the intestinal epithelial barrier in tumor necrosis factor-α (TNF-α) induced Caco-2 cells and dextran sulfate sodium (DSS) induced colitis in mice. Results show that Picroside III significantly alleviated clinical signs of colitis including body weight loss, disease activity index increase, colon shortening, and colon tissue damage. It also increased claudin-3, ZO-1 and occludin expressions and decreased claudin-2 expression in the colon tissues of mice with colitis. In vitro, Picroside III also significantly promoted wound healing, decreased the permeability of cell monolayer, upregulated the expressions of claudin-3, ZO-1 and occludin and downregulated the expression of claudin-2 in TNF-α treated Caco-2 cells. Mechanism studies show that Picroside III significantly promoted AMP-activated protein kinase (AMPK) phosphorylation in vitro and in vivo, and blockade with AMPK could significantly attenuate the upregulation of Picroside III in ZO-1 and occludin expressions and the downregulation of claudin-2 expression in TNF-α treated Caco-2 cells. In conclusion, this study demonstrates that Picroside III attenuated DSS-induced colitis by promoting colonic mucosal wound healing and epithelial barrier function recovery via the activation of AMPK.

Artemotil mediates protection in experimental colitis through the induction of Type 1 regulatory T cells

Abstract Artemotil (β-arteether) is a semi-synthetic derivative of artemisinin - a natural compound isolated from the plant Artemisia annuaand used worldwide as a front-line anti-malarial drug. Besides its anti-malarial effect, several studies have reported its potential use as an anti-tumor and anti-inflammatory agent. Artemotil was found to suppress the generation and function of Th1 and Th17 while promoting the generation of Foxp3+ regulatory T cells (Tregs). The role of Artemotil in modulating the generation and functions of Type 1 regulatory T cells is not yet identified. Tr1 cells are one of the key cell types that are essential for inhibiting inflammatory response through IL-10. In this study, we report an additional role of Artemotil by selectively inducing the generation of Tr1 cells induced by IL-27 by upregulating the signature of Tr1 cells genes such as c-maf and Prdm1, IRF-1, and Batf. We found that co-administer of Artemotil with anti-CD3 antibody increases the induction of IL-10 and frequency of Tr1 cells while suppressing Th1 and Th17 cells in vivo associated with less severe T-cell-induced enteropathy and intestinal inflammation. We further show the anti-inflammatory role of Artemotil in the chronic T-cell-induced colitis model in which Artemotil treatment alleviates the signs of colitis associated with the increased frequencies of Tr1 cells. Taken together, these data suggest that Artemotil provides protection in T-cell-mediated colitis by increasing the expansion of Tr1 cells and inhibiting the generation of Th1 and Th17 cells. This study was supported by grants from Science &amp; Engineering Research Board (SERB), Department of Science and Technology (DST), Government of India (CRG/2018/002653)

ON104, a novel antibody targeting oxidized Macrophage Migration Inhibitory Factor (oxMIF) shows efficacy in preclinical models of chronic inflammation

Abstract Macrophage Migration Inhibitory Factor (MIF) is a pleiotropic inflammatory cytokine, ubiquitously present in various tissues and the circulation of healthy subjects. MIF is a primary counter-actor of glucocorticoids that emerged as a pivotal regulator of chronic inflammation. During inflammation, MIF converts into oxidized (ox)MIF which was described as the pathogenic and druggable isoform of MIF. ON104, a fully human antibody, was engineered to specifically neutralize oxMIF without triggering immune cell effector functions. ON104 was tested in three experimental models of chronic inflammatory diseases (CIDs): Glomerulonephritis (GN) in WKY rats, Collagen-Induced Arthritis (CIA) in DBA/1j mice; and adoptive T-cell transfer colitis in SCID mice. At disease onset, ON104 was administered at different dose levels twice a week for 1, 3, and 8 weeks in GN, CIA, and colitis, respectively. Clinical evaluations, blood and tissue sampling were done for all individual animals. In the GN model, ON104 significantly reduced proteinuria, hematuria, and CD68 +macrophage infiltration within the inflamed kidneys. During CIA, ON104 ameliorated the severity of arthritis as indicated by reduced paw thickness, and decreased disease score. Furthermore, treatment with ON104 substantially attenuated clinical signs of colitis by preventing body weight loss and restoring stool consistency compared to the vehicle-treated controls. Our findings substantiate the role of oxMIF in the pathogenesis of various CIDs. Thus, ON104 has the potential to become a well-tolerated therapeutic antibody for treating patients with CIDs.

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&lt;0.05), followed by an increase in IFNγ-producing CD4 T cells at 8-wks of age (n≥7, p&lt;0.05). ELS-exposed mice also displayed reduced levels of the glucocorticoid, corticosterone in the plasma (n≥10, p&lt;0.01) as well as locally within the colon (n≥7, p&lt;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&lt;0.01) and histological signs of colitis (n≥7, p&lt;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&lt;0.05) and responsiveness ( Nr3c1, Nr5a2; n≥5, p&lt;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&lt;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.

Network Pharmacology Study of Bioactive Components and Molecular Mechanisms of the Glycoside Fraction from Picrorhiza scrophulariiflora Against Experimental Colitis.

To explore the potential mechanism of glycosidic fraction of Picrorhiza scrophulariiflora Pennell (GPS) extract for the treatment of colitis using UPLC-QTOF-MS analysis, network pharmacology and experimental research. The active components of GPS extract were identified by UPLC-QTOF-MS analysis and extracted their targets from the databases, which was used for network pharmacology analysis. Kyoto Encyclopedia of genes and genomes (KEGG) pathway analysis was performed to discover potential therapeutic mechanisms, and the network pharmacology results were then validated by in vivo and in vitro experiments. The results showed that GPS extract significantly alleviated the clinical signs of colitis, including body weight, disease activity index, colon shortening, and colon tissue damage, and inhibited the transcription and production of colonic IL-1β and IL-6 in DSS-induced colitis mice. In vitro, GPS extract also significantly suppressed nitric oxide (NO) production, iNOS expression, IL-1β and IL-6 transcription of LPS-activated RAW 264.7 cells. Network pharmacology integrated with experimental validation identified that GPS extract significantly suppressed Akt, p38, ERK, and JNK phosphorylation in vivo and in vitro, and luteolin, apocynin, caffeic acid, caffeic acid methyl ester, luteoloside, picroside II, aucubin, cinnamic acid, vanillic acid, and sweroside were the main components responsible for the anti-inflammatory effect of GPS. These findings demonstrate that the potential anti-inflammatory effect of GPS extract against colitis is achieved through suppressing PI3K/Akt and MAPK pathways, and that the abovementioned active components mainly exerted its anti-inflammatory effect. The therapeutic effect of GPS extract on colitis is related to PI3K/Akt and MAPK pathways, which is a promising remedy for colitis therapy.

A51 INTESTINAL MICROBIOTA DETERMINES ARYL HYDROCARBON RECEPTOR ACTIVATION AND SUSCEPTIBILITY TO COLITIS

Abstract Background Intestinal microbiota, diet, and the immune system have been proposed to contribute to the development of inflammatory bowel diseases (IBD). The aryl hydrocarbon receptor (AhR) is a critical regulator of intestinal immunity and mucosal barrier homeostasis that is activated by agonists such as host and microbial tryptophan metabolites. IBD patients have altered microbiota and reduced AhR agonists in intestinal content resulting in the downregulation of AhR. These findings necessitate further study to understand how diet-microbiota interactions contribute to intestinal inflammation. Purpose To study the influence of intestinal microbiota on tryptophan metabolism, AhR activation, and colitis severity. Method 8- to 10-week-old germ-free C57BL/6 mice were colonized with cecal content of mice harbouring specific pathogen-free (SPF) or a limited and well-defined altered Schaedler flora (ASF) microbiota. Germ-free mice were used as controls. Three weeks following colonization, mucosal injury was induced in a subset of mice with dextran sulfate sodium (DSS) in drinking water for five days followed by two days of water recovery. Activation of AhR was measured in stool using an in vitro AhR luciferase reporter assay. Stool AhR agonists were determined using high-performance liquid chromatography coupled to high-resolution mass spectrometry. Colonic expression of AhR pathway genes Cyp1a1, Il22, Ahrr, Ahr, and Il17 was evaluated by RT-qPCR. Susceptibility to colitis was assessed by analysing stool consistency and stool blood, colonic microscopic damage, immune infiltration by immunohistochemistry, and pro-inflammatory gene expression (NanoString). Fecal microbiota was analysed by 16S rRNA gene sequencing (Illumina). Result(s) AhR agonists, AhR activation in vitro, and AhR pathway gene expression were elevated in mice colonized with SPF microbiota in comparison to mice colonized with ASF microbiota and germ-free mice. In ASF-colonized mice, DSS induced more severe inflammation than in SPF-colonized mice, as demonstrated by worsened mucosal injury, greater weight loss, and softer stools. SPF-colonized mice developed less mucosal immune cell infiltration and pro-inflammatory gene signaling. Conclusion(s) Our findings suggest that intestinal microbiota composition determines the metabolic capacity to degrade tryptophan into agonists that homeostatically activate AhR. When mucosal injury is induced, mice with elevated microbiota-derived AhR agonists and AhR activation develop less severe mucosal injury and signs of colitis. This study presents a useful tool for evaluating dietary and microbial therapies in the context of a microbiota with impaired tryptophan metabolism. Please acknowledge all funding agencies by checking the applicable boxes below CCC, CIHR Disclosure of Interest None Declared