Inflammatory Bowel Disease: Pathophysiology and Current Therapeutic Approaches

Pomegranate seed oil mitigates liver and kidney damage in an experimental colitis model: Modulation of NF-κB activation and apoptosis

Pomegranate seed oil, extracted from pomegranate seeds, is a slightly fragrant yellow oil with a mild odor. Pomegranate seed oil is the main source of punicic acid (conjugated linolenic acid). Punicic acid is a long-chain omega-5 polyunsaturated fatty acid and a conjugated α-linolenic acid molecule. This acid is thought to provide many health benefits. This study evaluated the potential of pomegranate seed oil to attenuate damage to liver and kidney tissues in an acetic acid-induced colitis model. 32 male Sprague-Dawley rats were divided into 4 groups: control, colitis, 0.4 ml/kg, and 0.8 ml/kg pomegranate seed oil treatment after colitis. At the end of the experiment, histopathological and immunohistochemistry analyses of liver and kidney tissues were performed. Pomegranate seed oil treatment reduced damage in liver and kidney tissues, suppressed NF-κB activation, and regulated apoptosis. These findings support the potential effects of pomegranate seed oil against extraintestinal symptoms of colitis through its anti-inflammatory, and anti-apoptotic properties.

The Interaction between Stress and Inflammatory Bowel Disease in Pediatric and Adult Patients

Background: Inflammatory bowel diseases (IBDs) have seen an exponential increase in incidence, particularly among pediatric patients. Psychological stress is a significant risk factor influencing the disease course. This review assesses the interaction between stress and disease progression, focusing on articles that quantified inflammatory markers in IBD patients exposed to varying degrees of psychological stress. Methods: A systematic narrative literature review was conducted, focusing on the interaction between IBD and stress among adult and pediatric patients, as well as animal subjects. The research involved searching PubMed, Scopus, Medline, and Cochrane Library databases from 2000 to December 2023. Results: The interplay between the intestinal immunity response, the nervous system, and psychological disorders, known as the gut-brain axis, plays a major role in IBD pathophysiology. Various types of stressors alter gut mucosal integrity through different pathways, increasing gut mucosa permeability and promoting bacterial translocation. A denser microbial load in the gut wall emphasizes cytokine production, worsening the disease course. The risk of developing depression and anxiety is higher in IBD patients compared with the general population, and stress is a significant trigger for inducing acute flares of the disease. Conclusions: Further large studies should be conducted to assess the relationship between stressors, psychological disorders, and their impact on the course of IBD. Clinicians involved in the medical care of IBD patients should aim to implement stress reduction practices in addition to pharmacological therapies.

Lipid-lowering drugs and inflammatory bowel disease's risk: a drug-target Mendelian randomization study

BACKGROUND

Inflammatory bowel disease (IBD) has been associated with lipid-lowering drugs in observational studies. Drug-target Mendelian randomization (MR) was utilized in this study to examine the causal relationship between lipid-lowering drugs and incidence of IBD, aiming to identify new preventive uses for the drugs.

METHODS

We identified instrumental variables for three classes of lipid-lowering drugs: HMGCR inhibitors, PCSK9 inhibitors, and NPC1L1 inhibitors, using data from the Global Lipids Genetics Consortium. Summary statistics of IBD were obtained from UK Inflammatory Bowel Disease Genetics. The summary-data-based MR (SMR) and the inverse-variance weighted (IVW) MR were used for analysis. Sensitivity analyses were performed by conventional MR methods.

RESULTS

The SMR analysis showed no significant genetic association between increased gene expression of HMGCR, PCSK9, and NPC1L1 and IBD, Crohn's disease (CD) and ulcerative colitis (UC). According to IVW-MR analysis, increased HMGCR expression is associated with a reduced risk of IBD (OR = 0.73, 95% confidence interval (CI) 0.59-0.90, P = 0.003) and CD (OR = 0.75, 95% CI 0.57-0.97, P = 0.03), but not with UC. Additionally, increased NPC1L1 gene expression was associated with elevated risk of IBD (OR = 1.60, 95% CI 1.07-2.40, P = 0.023), but not with CD and UC. However, no significant causal relationships were found between PCSK9 gene expression and IBD, CD, and UC. The sensitivity analysis demonstrated no evidence of heterogeneity or pleiotropy among the reported results.

CONCLUSIONS

The heightened expression of genetic variations in HMGCR inhibitor targets could potentially reduce the risk of IBD and CD, while genetic variation in the expression of NPC1L1 targets was positively associated with IBD.

Synergistic effect of berberine hydrochloride and dehydrocostus lactone in the treatment of ulcerative colitis: Take gut microbiota as the target

Ulcerative colitis (UC) is a difficult-to-cure and recurrent inflammatory bowel disease, and it is difficult to maintain long-term results with a single drug. Inspired by clinical medication in traditional Chinese medicine, we used berberine hydrochloride (BBH) and dehydrocostus lactone (DEH) in combination for the first time and focused on studying their mechanism of treating UC based on gut microbiota. Therefore, we evaluated the therapeutic effects of BBH and DEH on DSS-induced UC mice using ELISA, HE and AB-PAS staining, 16s rDNA amplicon sequencing technology, and fecal transplantation experiments (FMT). In this study, the combination of BBH and DEH significantly relieved symptoms, colonic inflammation, and intestinal barrier damage of DSS-induced UC mice, and they did not show antagonism. In addition, the co-administration of BBH and DEH altered the composition and function of gut microbiota, with BBH increasing the abundance of key beneficial bacterial genus Akkermansia and DEH aiming to enhance species diversity and supplying intestinal proteins to prevent overconsumption. Furthermore, our data showed that BBH and DEH improve the levels of short-chain fatty acids, which also proved the positive regulation of gut microbiota by BBH and DEH. Finally, the FMT confirmed the strong correlation between BBH, DEH, and the gut microbiota. In conclusion, the co-administration of BBH and DEH protected the intestinal barrier and reduced inflammatory damage by regulating gut microbiota, targeting the key beneficial bacterial genus Akkermansia, and maintaining a normal supply of intestinal proteins.

Antioxidant Therapy in Inflammatory Bowel Disease: A Systematic Review and a Meta-Analysis of Randomized Clinical Trials

The objective of this study is to assess the effectiveness of treatment for inflammatory bowel diseases in modulating oxidative stress biomarkers and cytokine levels. A systematic review of clinical trials was conducted, searching electronic databases including PubMed, Science Direct, and Scopus. After excluding articles that did not meet the inclusion criteria, 19 studies were included in the systematic review and 8 in the meta-analysis (6 for antioxidant capacity, 6 for superoxide dismutase (SOD), and 5 for lipid peroxidation analyzed through malondialdehyde (MDA) levels). SOD was significantly modulated (RR = 0.3764, 95% CI [0.0262 to 0.7267], p = 0.035) but not antioxidant capacity (RR = 0.3424, 95% CI [0.0334 to 0.7183], p = 0.0742) or MDA (RR = -0.8534, 95% CI [-1.9333 to 0.2265], p = 0.1214). Nonetheless, studies investigating oxidative stress biomarkers and cytokines in the context of alternative therapies for IBD treatment are still scarce. This review highlights the potential of antioxidant supplementation in IBD management and underscores the need for further investigations into its effects on oxidative stress biomarkers and cytokines to improve therapeutic approaches for IBD patients.

A retrospective analysis of treatment patterns, drug discontinuation and healthcare costs in Crohn's disease patients treated with biologics

BACKGROUND/AIMS

This real-world analysis evaluated the persistence and direct healthcare costs of Crohn's Disease (CD) patients treated with biologics in Italy.

METHODS

A retrospective analysis on administrative databases of Italian healthcare entities, covering 10.4 million residents, was performed. Adult CD patients under biologics between 2015 and 2020 were included and attributed to first/second treatment line based on absence/presence of biologic prescriptions 5-years before index-date (first biologic prescription).

RESULTS

Of 16,374 CD patients identified, 1,398 (8.5%) were biologic-treated: 1,256 (89.8%) in first line and 135 (9.7%) in second line. Kaplan-Meier curves estimated a higher persistence for ustekinumab-treated patients followed by vedolizumab, infliximab and adalimumab, in both lines. Considering baseline variables and adalimumab as reference, infliximab in first line (HR: 0.537) and ustekinumab in first (HR: 0.057) and second line (HR: 0.213) were associated with significantly reduced risk of drug-discontinuation. First line total/average healthcare direct-costs were €13,637, €11,201, €17,104 and €18,340 in patients persistent on adalimumab, infliximab, ustekinumab and vedolizumab, respectively.

CONCLUSIONS

This real-world analysis showed differences in persistence over 12-months between biologic treatments, being higher in ustekinumab-treated group, followed by vedolizumab, infliximab and adalimumab. Patients' management was associated with comparable direct healthcare costs among treatment lines, mainly driven by drug-related expenses.

Performance of fecal S100A12 as a novel non-invasive diagnostic biomarker for pediatric inflammatory bowel disease: a systematic review and meta-analysis

OBJECTIVE

The incidence and prevalence of inflammatory bowel disease (IBD) in pediatric patients are increasing. Currently, the diagnostic method for IBD is inconvenient, expensive, and difficult. S100A12, a type of calcium-binding protein, detected in the feces of patients with IBD has recently been suggested as a promising diagnostic tool. Hence, the authors aimed to evaluate the accuracy of fecal S100A12 in diagnosing IBD in pediatric patients by performing a meta-analysis.

METHODS

The authors performed a systematic literature search in five electronic databases for eligible studies up to July 15, 2021. Pooled diagnostic accuracies of fecal S100A12 were analyzed as the primary outcomes. Secondary outcomes were standardized mean difference (SMD) of fecal S100A12 levels between IBD and non-IBD groups and a comparison of diagnostic accuracies between fecal S100A12 and fecal calprotectin.

RESULTS

Seven studies comprising 712 children and adolescents (474 non-IBD controls and 238 IBD cases) were included. Fecal S100A12 levels were higher in the IBD group than in the non-IBD group (SMD = 1.88; 95% confidence interval [CI] = 1.19-2.58; p < 0.0001). Fecal S100A12 could diagnose IBD in pediatric patients with a pooled sensitivity of 95% (95% CI = 88%-98%), specificity of 97% (95% CI = 95%-98%), and area under the receiver operating summary characteristics (AUSROC) curve of 0.99 (95% CI = 0.97-0.99). Fecal S100A12 specificity and AUSROC curve values were higher than those of fecal calprotectin (p < 0.05).

CONCLUSION

Fecal S100A12 may serve as an accurate and non-invasive tool for diagnosing pediatric IBD.

Advancements in Inflammatory Bowel Disease: A Narrative Review of Diagnostics, Management, Epidemiology, Prevalence, Patient Outcomes, Quality of Life, and Clinical Presentation

Inflammatory bowel disease (IBD), encompassing ulcerative colitis (UC) and Crohn's disease (CD), is a chronic, immune-mediated disorder that impacts the gastrointestinal tract. Significant advancements in the diagnosis and treatment of IBD have been made during the past few decades, improving patient outcomes. This narrative review aims to provide an overview of recent developments in the diagnosis and treatment of IBD. Both from an evaluative and therapeutic standpoint, the management of IBD has undergone significant change. The standard of treatment for treating UC and CD patients has changed due to several medical developments. These developments include amino-salicylates, immunosuppressants, biological agents, and new therapeutics. The review also addresses the difficulties in applying these developments in clinical practice. Globally, the prevalence of IBD is rising, with Asia among the regions with the highest rates. These environments provide particular difficulties, such as poor disease knowledge, a lack of diagnostic services, and infectious IBD mimics. These issues must be resolved to diagnose and manage IBD in these populations accurately. New imaging modalities and other improvements in diagnostic methods have increased the precision and early identification of IBD. To reduce problems and improve patient outcomes, healthcare professionals treating patients with IBD must work effectively as a team. An extensive summary of current developments in the diagnosis and treatment of IBD is given in this narrative review. It draws attention to the therapeutic possibilities, difficulties, and uncertainties of integrating these developments into clinical practice. By keeping up with these changes, healthcare practitioners can better care for patients with IBD and improve their quality of life.

Stem Cell Therapy in Inflammatory Bowel Disease: A Review of Achievements and Challenges

Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), is a group of chronic inflammatory diseases of the gastrointestinal tract. Repeated inflammation can lead to complications, such as intestinal fistula, obstruction, perforation, and bleeding. Unfortunately, achieving durable remission and mucosal healing (MH) with current treatments is difficult. Stem cells (SCs) have the potential to modulate immunity, suppress inflammation, and have anti-apoptotic and pro-angiogenic effects, making them an ideal therapeutic strategy to target chronic inflammation and intestinal damage in IBD. In recent years, hematopoietic stem cells (HSCs) and adult mesenchymal stem cells (MSCs) have shown efficacy in treating IBD. In addition, numerous clinical trials have evaluated the efficiency of MSCs in treating the disease. This review summarizes the current research progress on the safety and efficacy of SC-based therapy for IBD in both preclinical models and clinical trials. We discuss potential mechanisms of SC therapy, including tissue repair, paracrine effects, and the promotion of angiogenesis, immune regulation, and anti-inflammatory effects. We also summarize current SC engineering strategies aimed at enhancing the immunosuppressive and regenerative capabilities of SCs for treating intestinal diseases. Additionally, we highlight current limitations and future perspectives of SC-related therapy for IBD.

Development of a Prediction Model for Short-Term Remission of Patients with Crohn's Disease Treated with Anti-TNF Drugs

Therapy with anti-tumor necrosis factor (TNF) has dramatically changed the natural history of Crohn's disease (CD). However, these drugs are not without adverse events, and up to 40% of patients could lose efficacy in the long term. We aimed to identify reliable markers of response to anti-TNF drugs in patients with CD. A consecutive cohort of 113 anti-TNF naive patients with CD was stratified according to clinical response as short-term remission (STR) or non-STR (NSTR) at 12 weeks of treatment. We compared the protein expression profiles of plasma samples in a subset of patients from both groups prior to anti-TNF therapy by SWATH proteomics. We identified 18 differentially expressed proteins (p ≤ 0.01, fold change ≥ 2.4) involved in the organization of the cytoskeleton and cell junction, hemostasis/platelet function, carbohydrate metabolism, and immune response as candidate biomarkers of STR. Among them, vinculin was one of the most deregulated proteins (p < 0.001), whose differential expression was confirmed by ELISA (p = 0.054). In the multivariate analysis, plasma vinculin levels along with basal CD Activity Index, corticosteroids induction, and bowel resection were factors predicting NSTR.

Treatment Effects of Natural Products on Inflammatory Bowel Disease In Vivo and Their Mechanisms: Based on Animal Experiments

Inflammatory bowel disease (IBD) is a chronic, non-specific inflammatory disease of the intestine that can be classified as ulcerative colitis (UC) and Crohn's disease (CD). Currently, the incidence of IBD is still increasing in developing countries. However, current treatments for IBD have limitations and do not fully meet the needs of patients. There is a growing demand for new, safe, and highly effective alternative drugs for IBD patients. Natural products (NPs) are used in drug development and disease treatment because of their broad biological activity, low toxicity, and low side effects. Numerous studies have shown that some NPs have strong therapeutic effects on IBD. In this paper, we first reviewed the pathogenesis of IBD as well as current therapeutic approaches and drugs. Further, we summarized the therapeutic effects of 170 different sources of NPs on IBD and generalized their modes of action and therapeutic effects. Finally, we analyzed the potential mechanisms of NPs for the treatment of IBD. The aim of our review is to provide a systematic and credible summary, thus supporting the research on NPs for the treatment of IBD and providing a theoretical basis for the development and application of NPs in drugs and functional foods.

Development of an Inflammatory Bowel Disease-Specific Medication Adherence Instrument and Reasons for Non-adherence

BACKGROUND

Medication adherence impacts disease control in inflammatory bowel disease (IBD). Existing adherence measures such as the Morisky Medication Adherence Scale 8^© are often costly, non-medication-specific, and time-consuming.

AIMS

We aimed to develop a non-proprietary, IBD-specific medication adherence instrument and to assess reasons for suboptimal medication adherence.

METHODS

We developed the IBD Medication Adherence Tool to assess frequency of adherence and indications for missed or delayed medication doses. We co-administered the IBD Medication Adherence Tool and the Morisky Medication Adherence Scale 8^© (licensed for use) to participants enrolled in an internet-based cohort of adults with IBD and taking least one daily, oral IBD medication. We used Spearman's correlation to evaluate associations between the IBD Medication Adherence Tool and Morisky Medication Adherence Scale 8^©. We then categorized patients as sub-optimally adherent (IBD Medication Adherence Tool score 1-4) and highly adherent (score 5) and evaluated factors associated with and reasons for suboptimal adherence using multivariable analysis.

RESULTS

We evaluated 514 patients (73% female, mean age 49), of whom 21.4% had suboptimal adherence. IBD Medication Adherence Tool scores were moderately correlated with Morisky Medication Adherence Scale 8^© (r = 0.56, p < 0.001). The most commonly reported reasons for suboptimal adherence were forgetting, feeling well, and cost. Younger age and current smoking were associated with suboptimal adherence.

CONCLUSIONS

We developed a non-proprietary, IBD-specific tool to assess adherence to IBD medications, validated in a cohort of patients with IBD on daily, oral medications. Common reasons for suboptimal IBD medication adherence include forgetting, feeling well, and cost.

The role of cholesterol and mitochondrial bioenergetics in activation of the inflammasome in IBD

Inflammatory Bowel Disease (IBD) is characterized by a loss of intestinal barrier function caused by an aberrant interaction between the immune response and the gut microbiota. In IBD, imbalance in cholesterol homeostasis and mitochondrial bioenergetics have been identified as essential events for activating the inflammasome-mediated response. Mitochondrial alterations, such as reduced respiratory complex activities and reduced production of tricarboxylic acid (TCA) cycle intermediates (e.g., citric acid, fumarate, isocitric acid, malate, pyruvate, and succinate) have been described in in vitro and clinical studies. Under inflammatory conditions, mitochondrial architecture in intestinal epithelial cells is dysmorphic, with cristae destruction and high dynamin-related protein 1 (DRP1)-dependent fission. Likewise, these alterations in mitochondrial morphology and bioenergetics promote metabolic shifts towards glycolysis and down-regulation of antioxidant Nuclear erythroid 2-related factor 2 (Nrf2)/Peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) signaling. Although the mechanisms underlying the mitochondrial dysfunction during mucosal inflammation are not fully understood at present, metabolic intermediates and cholesterol may act as signals activating the NLRP3 inflammasome in IBD. Notably, dietary phytochemicals exhibit protective effects against cholesterol imbalance and mitochondrial function alterations to maintain gastrointestinal mucosal renewal in vitro and in vivo conditions. Here, we discuss the role of cholesterol and mitochondrial metabolism in IBD, highlighting the therapeutic potential of dietary phytochemicals, restoring intestinal metabolism and function.

Extracellular vesicle miRNAs promote the intestinal microenvironment by interacting with microbes in colitis

Inflammatory bowel disease (IBD) is a global disease with no cure. Disruption of the microbial ecosystem is considered to be an important cause of IBD. Extracellular vesicles (EVs) are vital participants in cell-cell and cell-organism communication. Both host-derived EVs and bacteria-derived membrane vesicles (OMVs) contribute to homeostasis in the intestine. However, the roles of EVs-miRNAs and MVs in host-microbe interactions in colitis remain unclear. In the present study, the animal model of colitis was established by dextran sulfate sodium (DSS) to investigate the changes of miRNAs in colonic EVs from colitis. Several miRNAs were significantly altered in colitis EVs. miR-181b-5p transplantation inhibited M1 macrophage polarization and promoted M2 polarization to reduce the levels of inflammation both in acute and remission of chronic colitis. miR-200b-3p could interact with bacteria and regulate the composition of the microbiota, which contributed to intestinal barrier integrity and homeostasis. Notably, MVs from normal feces could effectively reverse the composition of the intestinal microbiota, restore the intestinal barrier and rescue colitis, and BMVs from colitis would also have similar effects after miR-200b-3p treatment. Our results preliminarily identify a vesicle-based host-microbe interaction cycle in colitis and provide new ideas for colitis treatment.

Identification of lncRNA DLEU2 as a potential diagnostic biomarker and anti-inflammatory target for ulcerative colitis

The incidence of ulcerative colitis (UC) in China has significantly increased over the past 10 years. Here we aim to explore potential diagnostic biomarkers and anti-inflammatory targets associated with UC. Patients with UC were enrolled in this study. The expression of lncRNAs and mRNAs in the nidus of the gut mucosa and adjacent normal mucosa samples was evaluated by RNA sequencing. The role of DLEU2 in inflammation and NF-κB signaling pathway was examined by RT-qPCR, Western blotting, and ELISA with human macrophage-like cells derived from THP-1. 564 lncRNAs and 859 mRNAs are significantly altered in the nidus of the gut mucosa of UC patients. Among the differentially expressed lncRNAs, DLEU2 changes the most. The expression of DLEU2 is negatively associated with inflammatory factors such as TNF-α, IL-1α, IL-1β, IL-6, and NLRP3. Mechanistically, DLEU2 exerts anti-inflammatory activity by inhibiting the NF-κB signaling pathway. In conclusion, the lncRNA DLEU2 in the intestinal mucosa is dysregulated upon gut inflammation and may act as a diagnostic biomarker and a therapeutic target for UC.

Mebendazole, an anti-helminth drug, suppresses inflammation, oxidative stress and injury in a mouse model of ulcerative colitis

Mebendazole (MBZ) is an efficacious anthelmintic with known anti-inflammatory and fibrinolytic properties. In this study, we aimed to explore the protective effects of this FDA-approved drug against DSS-induced colitis in a murine model either alone or in combination with Sulfasalazine (SSZ), a standard therapy for ulcerative colitis. We found that MBZ significantly improved colitis disease activity index as assessed by changes in body weight, degree of stool consistency, rectal bleeding, and prolapse. We also found that MBZ ameliorated the colon histopathological score by attenuating crypt loss, mucosal damage, and inflammation score in colitis tissues. Similarly, DSS-induced colon shortening, colon weight loss, and increase in spleen weight were all abrogated in the presence of MBZ. Moreover, MBZ decreased inflammation, possibly by reducing oxidative stress markers, suppressing inflammatory cell infiltration, and down-regulation of inflammatory genes in colon tissues. Furthermore, MBZ potently reduced fibrosis by decreasing collagen deposition and down-regulating pro-fibrotic genes including Col 1a1 and Col 1a2 in colitis tissue homogenates. In conclusion, our study showed that this broad-spectrum anthelminthic could be repurposed as a novel therapy for ulcerative colitis without any observed side effects, however, regarding the concerns about the potential toxicity of MBZ in UC patients, future experiments on MBZ therapy in other models of UC is needed to completely address the toxicity concerns.

Effects of Commercial Probiotics on Colonic Sensitivity after Acute Mucosal Irritation

Gastrointestinal pathologies associated with abdominal pain, such as irritable bowel syndrome or inflammatory bowel disease, lack sufficiently effective treatments. In our study we have used a rat model of visceral pain (72 animals; n = 8–13 per experimental group) to analyze the consequences of intracolonic administration of the irritant acetic acid on visceral sensitivity, histology of the colonic wall, and inflammatory response. Moreover, we have studied the possible beneficial effects of a pretreatment with a commercial probiotic (Actimel^®). Contrary to expectations, acetic acid application (7 cm proximal to the anus) decreased the nociceptive response to intracolonic mechanical stimulation, with a slight increase in the histological damage of colonic mucosa. The intensity of these changes depended on the concentration (4% or 0.6%) and the time of application (30 or 60 min). Pretreatment with probiotics (by daily gavage, for 1 week) normalized the values obtained in the visceral sensitivity test but revealed an increase in the number of macrophages. These results suggest a possible activation of inhibitory mechanisms early after colonic irritation, not previously described (which need further experimental confirmation), and the ability of probiotics to normalize the effects of acetic acid. In addition, pretreatment with probiotics has a direct effect on immune functions, stimulating macrophagic activity.

Stress and Inflammatory Bowel Disease: Clear Mind, Happy Colon

Inflammatory bowel disease (IBD) is a condition whose prevalence in the general population worldwide is increasing at an exponential pace. Many risk factors affect the incidence, progression, and overall outcome of IBD, one of them being psychological stress. This study examined the relationship between psychological stress and inflammatory bowel disease.

A search for relevant studies was conducted using PubMed, Google Scholar, ResearchGate, and SCOPUS. A systematic review was conducted on the relevant articles after critical appraisal.

This article mainly focused on studies that evaluated the presence of inflammatory markers observed in individuals who have been diagnosed with IBD and have high levels of psychological stress. It also assessed if lowering an individual’s psychological stress could help improve the outcomes of IBD.

Psychological stress can have a detrimental effect on individuals diagnosed with IBD. There is a need to conduct studies that can further confirm the association between psychological stressors, mental health conditions, and IBD. We should also encourage medical practitioners to educate patients who have been diagnosed with IBD regarding the benefits of stress reduction.

Indoleamine-2,3-dioxygenase-related anti-inflammatory effects of 3-aminobenzamide and infliximab in experimental colitis

OBJECTIVE

This study aimed to investigate the presence of indoleamine-2,3-dioxygenase and bacterial translocation after the administration of 3-aminobenzamide and infliximab in the TNBS model of rat colitis.

METHODS

The study group was divided into five categories as follows: group 1: (control), group 2: colitis+saline, group 3: colitis+3-aminobenzamide, group 4: colitis+infliximab, and group 5: colitis+3-aminobenzamide+infliximab. Intestinal mesenteric cultures were incubated on specific agar media plates under aerobic and anaerobic conditions, bacterial translocation was evaluated and assessed as colony-forming units per gram of tissue. Colonic tissue samples were evaluated by Western blotting method to detect the presence of indoleamine-2,3-dioxygenase.

RESULTS

The results obtained were as follows: group 1: normal gut flora; group 2: eight of nine samples had bacterial translocation, of which six of them had positive indoleamine-2,3-dioxygenase protein; group 3: five of nine samples had bacterial translocation, of which seven of them had positive indoleamine-2,3-dioxygenase; group 4: three of nine samples had bacterial translocation, of which seven of them had positive indoleamine-2,3-dioxygenase; and group 5: only one sample had exact indoleamine-2,3-dioxygenase protein.

CONCLUSION

Altered expression of indoleamine-2,3-dioxygenase results in a lower bacterial translocation via infliximab compared with 3-aminobenzamide treatment. Combined treatments emphasized different approaches for the new molecules related to indoleamine-2,3-dioxygenase.

Development and validation of HPLC-DAD and LC-(ESI)/MS methods for the determination of sulfasalazine, mesalazine and hydrocortisone 21-acetate in tablets and rectal suppositories: In vitro and ex vivo permeability studies

Controlled-release tablets and rectal suppositories of sulfasalazine (SLF) and hydrocortisone 21-acetate (HA) were prepared as recommended dosage forms for the treatment of acute episodes of ulcerative colitis, in patients who do not respond to monotherapy. A High-Performance Liquid Chromatography (HPLC) Diode-array method with a gradient elution mobile phase was developed to evaluate the production quality of both formulations (assay and dissolution profiles in gastric and intestinal fluids). Method's validation was carried out providing good linearity (r ≥ 0.9995), precision (RSD < 1.53%), recovery (96.9% - 103.7%) and limits of detection (LOD_SLF = 12 ng/mL, LOD_HA = 15 ng/mL). Experimental design and Plackett-Burman methodology was constructed to study the robustness of the analysis. In all composite substrates, a freezing lipid precipitation approach was used as purification step. The method was optimized by applying Central Composite design mode. The in-vitro/ex-vivo permeability studies of both formulations were evaluated by a Liquid Chromatography-Electron Spray Ionization Mass Spectrometry (LC-ESI/MS) +/- mode. The analysis of sulfamethazine (internal standard, SLM, m/z 279), HA (m/z 449, [M + HCOO]^-), SLF (m/z 399) and its active metabolite mesalazine (MSL, m/z 154) was performed using a C₁₈ column and gradient elution. The validation of the method met the requirements of the International Council for Harmonization (ICH) (r ≥ 0.9997, RSD ≤ 4.62%, Recovery > 95%, LOD_SLF = 1.28 ng/mL, LOD_HA = 1.07 ng/mL, LOD_MSL = 3.16 ng/mL). Based on the results, important conclusions were drawn concerning the role of excipients and SLF metabolism.

Artificial Intelligence Algorithm-Based Differential Diagnosis of Crohn's Disease and Ulcerative Colitis by CT Image

The aim of this study was to investigate the effect of low-dose CT enterography (CTE) based on modified guided image filtering (GIF) algorithm in the differential diagnosis of ulcerative colitis (UC) and Crohn's disease (CD). Methods. One hundred and twenty patients with suspected diagnosis of IBD were studied. They were randomly divided into control group (routine CT examination) and observation group (low-dose CTE examination based on improved GIF algorithm), with 60 cases in each group. Comprehensive diagnosis was used as the standard to assess the diagnostic effect. Results. (1) The peak signal-to-noise ratio (PSNR) (26.02 dB) and structural similarity (SSIM) (0.8921) of the algorithm were higher than those of GIF (17.22 dB/0.8491), weighted guided image filtering (WGIF) (23.78 dB/0.8489), and gradient domain guided image filtering (GGIF) (23.77 dB/0.7567) (P < 0.05); (2) the diagnostic sensitivity (91.49%), specificity (92.31%), accuracy (91.67%), positive predictive value (97.73%), and negative predictive value (75%) of the observation group were higher than those of the control group (P < 0.05); the sensitivity and specificity of CTE in the diagnosis of UD and CD were 96.77% and 81.25% and 98.33% and 93.33%, respectively (P < 0.05); there were significant differences in symmetrical intestinal wall thickening and smooth serosal surface between UD and CD (P < 0.05). Conclusion. (1) The improved GIF algorithm has a more effective application value in the denoising processing of low-dose CT images and can better improve the image quality; (2) the accuracy of CTE in the diagnosis of IBD is high, and CTE is of great value in the differential diagnosis of UD and CD.

The Complex Relationship Between Microbiota, Immune Response and Creeping Fat in Crohn's Disease

In the last decade, there has been growing interest in the pathological involvement of hypertrophic mesenteric fat attached to the serosa of the inflamed intestinal segments involved in Crohn's disease [CD], known as creeping fat. In spite of its protective nature, creeping fat harbours an aberrant inflammatory activity which, in an already inflamed intestine, may explain why creeping fat is associated with a greater severity of CD. The transmural inflammation of CD facilitates the interaction of mesenteric fat with translocated intestinal microorganisms, contributing to activation of the immune response. This may be not the only way in which microorganisms alter the homeostasis of this fatty tissue: intestinal dysbiosis may also impair xenobiotic metabolism. All these CD-related alterations have a functional impact on nuclear receptors such as the farnesoid X receptor or the peroxisome proliferator-activated receptor γ, which are implicated in regulation of the immune response, adipogenesis and the maintenance of barrier function, as well as on creeping fat production of inflammatory-associated cells such as adipokines. The dysfunction of creeping fat worsens the inflammatory course of CD and may favour intestinal fibrosis and fistulizing complications. However, our current knowledge of the pathophysiology and pathogenic role of creeping fat is controversial and a better understanding might provide new therapeutic targets for CD. Here we aim to review and update the key cellular and molecular alterations involved in this inflammatory process that link the pathological components of CD with the development of creeping fat.

Serum inter-alpha-trypsin inhibitor heavy chain 4 in patients with inflammatory bowel disease: correlation with disease risk, inflammation, activity, and its variation after treatment

BACKGROUND

Inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4) plays vital roles in inflammatory and auto-immune diseases, but its correlations with disease risk and clinical features in inflammatory bowel disease (IBD) need further investigation. The present study intended to explore the correlation of ITIH4 with disease activity and inflammation, as well as its change after treatment in IBD patients.

METHODS

Totally, 40 active Crohn's disease (A-CD) patients, 40 clinical-remission CD (R-CD) patients, 40 active ulcerative colitis (A-UC) patients, 40 clinical-remission UC (R-UC) patients, and 40 health controls (HCs) were enrolled. ITIH4 in serum was assessed by ELISA.

RESULTS

ITIH4 was lower in A-CD, R-CD, A-UC, and R-UC patients than in HCs (P < 0.001). Notably, ITIH4 reduced in A-CD patients than in R-CD patients (P = 0.017), and in A-UC patients compared with R-UC patients (P = 0.010). Besides, in A-CD patients, ITIH4 negatively correlated with tumor necrosis factor-alpha (TNF-α), interleukin (IL)-17A, IL-1β, C-reactive protein (CRP), and clinical disease activity index score (all P < 0.05). In A-UC patients, ITIH4 negatively correlated with TNF-α, IL-17A, IL-1β, IL-6, CRP, and Mayo score (all P < 0.05). However, in R-CD and R-UC patients, these correlations were less obvious than in A-CD and A-UC patients. ITIH4 was increased after treatment (all P < 0.05), and its expression at W12 after treatment was higher in response patients compared with no response patients in A-CD (P = 0.022) and A-UC groups (P = 0.038).

CONCLUSION

ITIH4 correlates with IBD susceptibility, active risk, inflammation level, and its elevation after treatment relates to clinical response in IBD patients.

Is endoscopic retrograde appendicitis therapy a better modality for acute uncomplicated appendicitis? A systematic review and meta-analysis

BACKGROUND

Previous studies had shown endoscopic retrograde appendicitis therapy (ERAT) is an effective treatment for acute appendicitis. However, different studies reported conflicting outcomes regarding the effectiveness of ERAT in comparison with laparoscopic appendectomy (LA).

AIM

To compare the effectiveness of ERAT with LA.

METHODS

Randomized controlled trials (RCTs) and retrospective studies of ERAT for acute uncomplicated appendicitis were searched in PubMed, Cochrane Library, Web of Science, Embase database, China National Knowledge Infrastructure (CNKI), the WanFang Database, and Chinese Scientific Journals Database (VIP) from the establishment date to March 1 2021. Heterogeneity was assessed using the I-squared statistic. Pooled odds ratios (OR), weighted mean difference (WMD), and standard mean difference (SMD), with 95% confidence intervals (CI) were calculated through either fixed-effects or random-effects model. Sensitivity analysis was also performed. Publication bias was tested by Egger's test, and Begg's test. The quality of included RCT were evaluated by the Jadad scale, while Newcastle-Ottawa scale is adopted for assessing the methodological quality of case-control studies. All statistical analysis was performed using Stata 15.1 statistical software. All statistical analysis was performed using Stata 15.1 statistical software. This study is registered with PROSPERO, CRD42021243955.

RESULTS

After screening, 10 RCTs and 2 case-control studies were included in the current systematic review. Firstly, the length of hospitalizations [WMD = -1.15, 95%CI: -1.99, -0.31; P = 0.007] was shorter than LA group. Secondly, the level of post-operative CRP [WMD = -10.06, 95%CI: (-17.39, -2.73); P = 0.007], TNF-α [WMD = -7.70, 95%CI: (-8.47, -6.93); P < 0.001], and IL-6 Levels [WMD = -9.78, 95%CI: (-10.69, -8.88); P < 0.001; P < 0.001] in ERAT group was significantly lower than LA group. Thirdly, ERAT group had a lower incidence of intestinal obstruction than LA group. [OR = 0.19, 95%CI: (0.05, 0.79); P = 0.020]. Moreover, the quality of 10 RCTs were low with 0-3 Jadad scores, while the methodological quality of two case-control studies were fair with a score of 2 (each).

CONCLUSION

Compared with LA, ERAT reduces operation time, the level of postoperative inflammation, and results in fewer complications and shorter recovery time, with preserving the appendix and its immune and biological functions.

MiRNA-182-5p aggravates experimental ulcerative colitis via sponging Claudin-2

Tight junction proteins play crucial roles in maintaining the integrity of intestinal mucosal barrier. MiRNA-182-5p is capable of targeting claudin-2 which is one of the vital tight junction proteins and the effect and mechanism of miRNA-182-5p was explored here in the DSS-induced colitis model. The pathological conditions were evaluated via hematoxylin and eosin staining. The gene expression level was assessed via PCR. Quantitative immunohistochemistry analysis was performed for the measurement of claudin-2. microRNA.org online tool was used for target gene prediction. Luciferase reporter assay and RNA pull-down assay were performed to detect the target of miRNA-182-5p. The inflammatory and oxidative stress level were measured using corresponding kits. MiRNA-182-5p was highly expressed in colitis model and miRNA-182-5p inhibitor exerted protective effects on colitis induced by DSS in mice. The protective effects includded improvement of pathological changes, increases in anti-inflammation and anti-oxidative genes, and up-regulation of TGF-β1. Claudin-2 mRNA was predicted as the target of miRNA-182-5p, which was validated via luciferase reporter assay and RNA pull-down assay. Claudin-2 overexpression was found in miRNA-182-5p inhibitor group. Consistent with the role of miRNA-182-5p, claudin-2 overexpression also exerted protective effects on DSS-induced colitis in mice. Inhibition of miRNA-182-5p exerted protective effects on colitis via targeting and upregulating claudin-2. The findings in study provide a new therapeutic strategy for colitis treatment and lay the foundation for future study.

Naringin Exerts Therapeutic Effects on Mice Colitis: A Study Based on Transcriptomics Combined With Functional Experiments

Naringin has been shown to exert protective effects in an animal model of ulcerative colitis, but detailed mechanisms remain unclear. This study aimed to investigate function and signaling mechanisms underlying naringin-induced therapeutic effects on colitis. Two mouse models were established to mimic human Inflammatory bowel disease (IBD) by treating drinking water with dextran sodium sulphate or intra-colonic administration of 2, 4, 6-trinitrobenzene sulfonic acid. Transcriptomics combined with functional experiments were used to investigate underlying mechanisms. Colitis symptoms, including weight loss and high disease activity index were significantly reversed by naringin. The inflammatory response, oxidative reactions, and epithelial cell apoptosis that occur with colitis were also alleviated by naringin. After naringin treatment, transcriptomics results identified 753 differentially expressed mRNAs that were enriched in signaling pathways, including the neuroactive ligand-receptor interaction, calcium signaling, and peroxisome proliferator-activated receptor (PPAR) signaling. The naringin-induced alleviation of colitis was significantly inhibited by the PPAR-γ inhibitor BADGE. In IEC-6 and RAW264.7 cells incubated with lipopolysaccharide (LPS), NF-κB-p65, a downstream protein of PPAR-γ, was significantly increased. Naringin suppressed LPS-induced high expression of NF-κB-p65, which was inhibited by small interfering RNA targeting PPAR-γ. Our study clarifies detailed mechanisms underlying naringin-induced therapeutic effects on mice colitis, and PPAR-γ was found to be the main target of naringin by functional experiments both in vivo and in vitro. Our study supplies new scientific information for the use of naringin in colitis treatment.

Receptor-mediated targeted drug delivery systems for treatment of inflammatory bowel disease: Opportunities and emerging strategies

Inflammatory bowel disease (IBD) is a chronic intestinal disease with painful clinical manifestations and high risks of cancerization. With no curative therapy for IBD at present, the development of effective therapeutics is highly advocated. Drug delivery systems have been extensively studied to transmit therapeutics to inflamed colon sites through the enhanced permeability and retention (EPR) effect caused by the inflammation. However, the drug still could not achieve effective concentration value that merely utilized on EPR effect and display better therapeutic efficacy in the inflamed region because of nontargeted drug release. Substantial researches have shown that some specific receptors and cell adhesion molecules highly expresses on the surface of colonic endothelial and/or immune cells when IBD occurs, ligand-modified drug delivery systems targeting such receptors and cell adhesion molecules can specifically deliver drug into inflamed sites and obtain great curative effects. This review introduces the overexpressed receptors and cell adhesion molecules in inflamed colon sites and retrospects the drug delivery systems functionalized by related ligands. Finally, challenges and future directions in this field are presented to advance the development of the receptor-mediated targeted drug delivery systems for the therapy of IBD.

The immunosuppressive activity of artemisinin-type drugs towards inflammatory and autoimmune diseases

The sesquiterpene lactone artemisinin from Artemisia annua L. is well established for malaria therapy, but its bioactivity spectrum is much broader. In this review, we give a comprehensive and timely overview of the literature regarding the immunosuppressive activity of artemisinin-type compounds toward inflammatory and autoimmune diseases. Numerous receptor-coupled signaling pathways are inhibited by artemisinins, including the receptors for interleukin-1 (IL-1), tumor necrosis factor-α (TNF-α), β3-integrin, or RANKL, toll-like receptors and growth factor receptors. Among the receptor-coupled signal transducers are extracellular signal-regulated protein kinase (ERK), c-Jun N-terminal kinase (JNK), phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K), AKT serine/threonine kinase (AKT), mitogen-activated protein kinase (MAPK)/extracellular signal regulated kinase (ERK) kinase (MEK), phospholipase C γ1 (PLCγ), and others. All these receptors and signal transduction molecules are known to contribute to the inhibition of the transcription factor nuclear factor κ B (NF-κB). Artemisinins may inhibit NF-κB by silencing these upstream pathways and/or by direct binding to NF-κB. Numerous NF-κB-regulated downstream genes are downregulated by artemisinin and its derivatives, for example, cytokines, chemokines, and immune receptors, which regulate immune cell differentiation, apoptosis genes, proliferation-regulating genes, signal transducers, and genes involved in antioxidant stress response. In addition to the prominent role of NF-κB, other transcription factors are also inhibited by artemisinins (mammalian target of rapamycin [mTOR], activating protein 1 [AP1]/FBJ murine osteosarcoma viral oncogene homologue [FOS]/JUN oncogenic transcription factor [JUN]), hypoxia-induced factor 1α (HIF-1α), nuclear factor of activated T cells c1 (NF-ATC1), Signal transducers and activators of transcription (STAT), NF E2-related factor-2 (NRF-2), retinoic-acid-receptor-related orphan nuclear receptor γ (ROR-γt), and forkhead box P-3 (FOXP-3). Many in vivo experiments in disease-relevant animal models demonstrate therapeutic efficacy of artemisinin-type drugs against rheumatic diseases (rheumatoid arthritis, osteoarthritis, lupus erythematosus, arthrosis, and gout), lung diseases (asthma, acute lung injury, and pulmonary fibrosis), neurological diseases (autoimmune encephalitis, Alzheimer's disease, and myasthenia gravis), skin diseases (dermatitis, rosacea, and psoriasis), inflammatory bowel disease, and other inflammatory and autoimmune diseases. Randomized clinical trials should be conducted in the future to translate the plethora of preclinical results into clinical practice.

Effect of supplementing fava bean (Vicia faba L.) on ulcerative colitis and colonic mucosal DNA content in rats fed a high-sucrose diet

Ulcerative colitis (UC) is an inflammatory bowel disease with high morbidity. Acetic acid-induced damage of colonic mucosa in rats is a commonly used experimental animal model of UC. This research aimed to explore for the first time the ameliorative effect of dietary supplementation with fava bean on the incidence of UC in rats fed with sucrose containing diet. Rats were divided into five groups as follows: G1, control healthy rats; G2, colitic rats; G3, colitic rats fed diets containing 30% sucrose, G4, healthy rats fed diets containing 30% sucrose and G5, colitic rats fed diets containing 30% sucrose supplemented with dried ground fava bean. Colonic injury and inflammation were evaluated through a disturbance of oxidative biomarkers, a significant increase in inflammatory biomarkers and inflammatory cytokines, and histological abnormalities in colonic tissues accompanied by colonic mucosal DNA damage. Colitic rats fed on sucrose containing diet demonstrated additional histological, biochemical, and DNA alterations in colonic mucosa of rats. Dietary supplementation with dried ground fava bean significantly corrected the impaired oxidative and inflammatory biomarker levels and modulated histological features and DNA alterations. Finally, fava bean attenuated the oxidative damage and colonic injury induced by acetic acid, which confirmed its high anti-oxidant and anti-incendiary properties.

Systems biology approach highlights mechanistic differences between Crohn's disease and ulcerative colitis

The molecular mechanisms of IBD have been the subject of intensive exploration. We, therefore, assembled the available information into a suite of causal biological network models, which offer comprehensive visualization of the processes underlying IBD. Scientific text was curated by using Biological Expression Language (BEL) and compiled with OpenBEL 3.0.0. Network properties were analysed by Cytoscape. Network perturbation amplitudes were computed to score the network models with transcriptomic data from public data repositories. The IBD network model suite consists of three independent models that represent signalling pathways that contribute to IBD. In the “intestinal permeability” model, programmed cell death factors were downregulated in CD and upregulated in UC. In the “inflammation” model, PPARG, IL6, and IFN-associated pathways were prominent regulatory factors in both diseases. In the “wound healing” model, factors promoting wound healing were upregulated in CD and downregulated in UC. Scoring of publicly available transcriptomic datasets onto these network models demonstrated that the IBD models capture the perturbation in each dataset accurately. The IBD network model suite can provide better mechanistic insights of the transcriptional changes in IBD and constitutes a valuable tool in personalized medicine to further understand individual drug responses in IBD.

Soluble ligands as drug targets for treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD), which includes Crohn's disease and ulcerative colitis, is characterized by persistent inflammation in a hereditarily susceptible host. In addition to gastrointestinal symptoms, patients with IBD frequently suffer from extra-intestinal complications such as fibrosis, stenosis or cancer. Mounting evidence supports the targeting of cytokines for effective treatment of IBD. Cytokines can be included in a newly proposed classification "soluble ligands" that has become the third major target of human protein therapeutic drugs after enzymes and receptors. Soluble ligands have potential significance for research and development of anti-IBD drugs. Compared with traditional drug targets for IBD treatment, such as receptors, at least three factors contribute to the increasing importance of soluble ligands as drug targets. Firstly, cytokines are the main soluble ligands and targeting of them has demonstrated efficacy in patients with IBD. Secondly, soluble ligands are more accessible than receptors, which are embedded in the cell membrane and have complex tertiary membrane structures. Lastly, certain potential target proteins that are present in membrane-bound forms can become soluble following cleavage, providing further opportunities for intervention in the treatment of IBD. In this review, 49 drugs targeting 25 distinct ligands have been evaluated, including consideration of the characteristics of the ligands and drugs in respect of IBD treatment. In addition to approved drugs targeting soluble ligands, we have also assessed drugs that are in preclinical research and drugs inhibiting ligand-receptor binding. Some new types of targetable soluble ligands/proteins, such as epoxide hydrolase and p-selectin glycoprotein ligand-1, are also introduced. Targeting soluble ligands not only opens a new field of anti-IBD drug development, but the circulating soluble ligands also provide diagnostic insights for early prediction of treatment response. In conclusion, soluble ligands serve as the third-largest protein target class in medicine, with much potential for the drugs targeting them.

Xi Lei San Attenuates Dextran Sulfate Sodium-Induced Colitis in Rats and TNF-α-Stimulated Colitis in CACO2 Cells: Involvement of the NLRP3 Inflammasome and Autophagy

Objective

Inflammatory bowel disease (IBD) is a chronic nonspecific inflammatory bowel disease with an unclear etiology. The active ingredients of traditional Chinese medicines (TCMs) exert anti-inflammatory, antitumor, and immunomodulatory effects, and their multitarget characteristics provide them with a unique advantage for treating IBD. However, the therapeutic effects and underlying mechanisms of Xi Lei San in treatment of IBD remain unknown. This study was designed to investigate whether Xi Lei San exerted an anti-inflammatory effect in IBD via a mechanism involving NLRP3 inflammasomes and autophagy.

Methods

We successfully established a rat model of dextran sulfate sodium- (DSS-) induced colitis as well as a cellular model of TNF-α-induced colitis. Xi Lei San and indirubin were identified by HPLC analysis. Rats were treated with Xi Lei San or alum crystals, and their body weights and morphology of intestinal tissues were examined. A western blot analysis was performed to determine the expression levels of inflammasome-related proteins and autophagy-related proteins, ELISA was performed to analyze IL-1β, IL-18, and IL-33 concentrations, and flow cytometry was used to monitor cell apoptosis and ROS levels.

Results

Xi Lei San and indirubin were identified by HPLC analysis. We found that Xi Lei San could significantly increase the weights of rats and improve the structure of the intestinal tissues in DSS-induced colitis model rats. We also found that Xi Lei San significantly inhibited NLRP3 inflammasome activity, reduced the levels of inflammatory cytokines, and suppressed autophagy in DSS-induced colitis model rats. In vitro experiments revealed that Xi Lei San could repress apoptosis as well as ROS and inflammatory cytokine production in TNF-α-induced CACO2 cells by reducing the activity of NLRP3 inflammasomes and autophagy.

Conclusions

Our findings showed that Xi Lei San significantly ameliorated IBD by inhibiting NLRP3 inflammasome, autophagy, and oxidative stress.

Development of an Advanced Multicellular Intestinal Model for Assessing Immunomodulatory Properties of Anti-Inflammatory Compounds

Intestinal inflammation is the collective term for immune system-mediated diseases of unknown, multifactorial etiology, with often complex interactions between genetic and environmental factors. To mechanistically investigate the effect of treatment with compounds possessing immunomodulating properties in the context of intestinal inflammation, we developed an immunocompetent in vitro triculture intestinal model consisting of a differentiated intestinal epithelial layer (Caco-2/HT29-MTX) and immunocompetent cells (differentiated THP-1). The triculture mimicked a healthy intestine with stable barrier integrity. Lipopolysaccharide treatment triggered a controlled and reversible inflammatory state, resulting in significant impairment of barrier integrity and release of pro-inflammatory cytokines and chemokines, which are known hallmarks of intestinal inflammation. Treatment with known anti-inflammatory reference compounds (TPCA-1 and budenoside) prevented the induction of an inflammatory state; the decreasing triculture responses to this treatment measured by cytokine release, transepithelial electric resistance (TEER), and epithelial layer permeability proved the suitability of the intestinal model for anti-inflammatory drug screening. Finally, selected tobacco alkaloids (nicotine and anatabine (R/S and S forms)) were tested in the in vitro triculture for their potential anti-inflammatory properties. Indeed, naturally occurring alkaloids, such as tobacco-derived alkaloids, have shown substantial anti-inflammatory effects in several in vitro and in vivo models of inflammation, gaining increasing interest. Similar to the anti-inflammatory reference compounds, one of the tobacco alkaloids under investigation partially prevented the decrease in the TEER and increase in permeability and reduced the release of pro-inflammatory cytokines and chemokines. Taken together, these data confirm that our in vitro model is suitable for screening potential anti-inflammatory compounds in the context of intestinal inflammation.

Mendelian randomization as an approach to assess causal effects of inflammatory bowel disease on atrial fibrillation

Background: Despite growing evidence indicating that patients with inflammatory bowel disease (IBD) have an increased risk of atrial fibrillation (AF), owing to the potential biases of confounding effects and reverse causation, the specific relationship between IBD and AF remains controversial. The aim of this study is to determine whether there is a causal effect of IBD on AF.

Methods: A two-sample Mendelian randomization (MR) study was performed to evaluate the causal effect of IBD on AF. Statistical summaries for the associations between single nucleotide polymorphisms (SNPs) and traits of interest were obtained from independent consortia with European populations. The dataset of IBD was acquired from genome-wide association studies (GWAS), including more than 75,000 cases and controls. A GWAS with 60,620 AF cases and 970,216 controls was used to identify genetic variation underlying AF. The causal effect was estimated using the multiplicative random effects inverse-variance weighted method (IVW), followed by sensitivity analysis.

Results: Using 81 SNPs, there was no evidence to suggest an association between genetically predicted IBD and risk of AF with multiplicative random-effects IVW MR analysis (odds ratio = 1.0000, 95% confidence interval: 0.9994 1.0005, p = 0.88).

Conclusion: As opposed to current assumptions, no substantial evidence was found to support a causal role of IBD in the development of AF.

Poly-pharmacokinetic strategy represented the synergy effects of bioactive compounds in a traditional Chinese medicine formula, Si Shen Wan and its separated recipes to normal and colitis rats

Si Shen Wan is a classic traditional Chinese medicine formula, which has been used to treat chronic colitis for thousands of years. Many research and experience show that Si Shen Wan was developed by the combination of two sets of "Herb Pairs," Er Shen Wan and Fructus Schisandrae Chinensis Powder. This research aimed to revealing the effective substances, guide the clinical treatment, and represent the synergy effects from the view of pharmacokinetics. An ultra high performance liquid chromatography with tandem mass spectrometry method was established and validated for simultaneous quantification of 26 main bioactive compounds in normal and colitis rat plasma after oral administration of Si Shen Wan and its "Herb Pairs" extract. The method validation results illustrated that the experimental method was reliable and reproducible for quantitative determination of the biological samples. The pharmacokinetic behaviors in different groups were compared and discussed comprehensively, which indicated that the treatment of Si Shen Wan has a superiority in synthetic action of the "Herb Pairs" for the higher peak concentrations and bioavailability of some mainly components. Furthermore, the synergy effect was still existing backed up again for the longer eliminate time and a better bioavailability in colitis groups. The pharmacokinetics research of multiple components in Si Shen Wan and its "Herb Pairs" supplied a significant basis for better understanding the metabolic mechanism of these formulas in both normal and pathological state.

Disrupted Circadian Rest-Activity Cycles in Inflammatory Bowel Disease Are Associated With Aggressive Disease Phenotype, Subclinical Inflammation, and Dysbiosis

Patients with inflammatory bowel disease (IBD)-Crohn's disease (CD), and ulcerative colitis (UC), have poor sleep quality. Sleep and multiple immunologic and gastrointestinal processes in the body are orchestrated by the circadian clock, and we recently reported that a later category or chronotype of the circadian clock was associated with worse IBD specific outcomes. The goal of this study was to determine if circadian misalignment by rest-activity cycles is associated with markers of aggressive disease, subclinical inflammation, and dysbiosis in IBD. A total of 42 patients with inactive but biopsy-proven CD or UC and 10 healthy controls participated in this prospective cohort study. Subjects were defined as having an aggressive IBD disease history (steroid dependence, use of biologic or immunomodulator, and/or surgery) or non-aggressive history. All participants did two weeks of wrist actigraphy, followed by measurement of intestinal permeability and stool microbiota. Wrist actigraphy was used to calculate circadian markers of rest-activity- interdaily stability (IS), intradaily variability (IV), and relative amplitude (RA). Aggressive IBD history was associated with decrease rest-activity stability (IS) and increased fragmentation compared to non-aggressive IBD and health controls at 0.39 ±.15 vs. 0.51 ± 0.10 vs. 0.55 ± 0.09 (P < 0.05) and 0.83 ± 0.20 vs. 0.72 ± 0.14 (P < 0.05) but not HC at 0.72 ± 0.14 (P = 0.08); respectively. There was not a significant difference in RA by IBD disease history. Increased intestinal permeability and increased TNF-α levels correlated with an increased rest activity fragmentation (IV) at R = 0.35, P < 0.05 and R = 0.37, P < 0.05, respectively; and decreased rest-activity amplitude (RA) was associated with increased stool calprotectin at R = 0.40, P < 0.05. Analysis of intestinal microbiota showed a significant decrease in commensal butyrate producing taxa and increased pro-inflammatory bacteria with disrupted rest-activity cycles. In this study, different components of circadian misalignment by rest-activity cycles were associated with a more aggressive IBD disease history, increased intestinal permeability, stool calprotectin, increased pro-inflammatory cytokines, and dysbiosis. Wrist activity allows for an easy non-invasive assessment of circadian activity which may be an important biomarker of inflammation in IB.

Protective Effect of Prunus mume Fermented with Mixed Lactic Acid Bacteria in Dextran Sodium Sulfate-Induced Colitis

The fruit of Prunus mume (PM) is widely cultivated in East Asia, and it has been used as a folk medication for gastrointestinal disorders, e.g., diarrhea, stomach ache and ulceration. In this study, the pectinase-treated PM juice (PJ) was fermented with Lactobacillus strains containing fundamental organic acids and free amino acids. The PJ fermented with Lactobacillus plantarum and L. casei (FP) was investigated for its protective effect in dextran sodium sulfate (DSS)-induced colitis mice model. The administration of FP reduced lipid peroxidation and histopathological colitis symptoms, e.g., shortening of the colon length, depletion of mucin, epithelial injury and ulceration, in colonic tissues. The FP-supplemented group showed the alleviation of pro-inflammatory cytokines. Compared with the DSS control group, the supplementation of FP significantly reduced the levels of serum interferon-γ (IFN-γ), interleukin (IL)-1β, IL-6, IL-12 and IL-17 as well as colonic tumor necrosis factor-α, IFN-γ, IL-12 and IL-17. Furthermore, the DSS-induced TUNEL-positive area was significantly reduced by the FP supplementation. These results show that the supplementation of FP fermented with mixed lactic acid bacteria, L. plantarum and L. casei, elucidated the protective effect in DSS-induced colitis mice. Hence, this study suggests that FP can be utilized as a natural therapeutic agent for colitis and intestinal inflammation.

Involvement of dopaminergic signaling in the cross talk between the renin-angiotensin system and inflammation

The renin-angiotensin system (RAS) is a fundamental regulator of blood pressure and has emerged as an important player in the control of inflammatory processes. Accordingly, imbalance on RAS components either systemically or locally might trigger the development of inflammatory disorders by affecting immune cells. At the same time, alterations in the dopaminergic system have been consistently involved in the physiopathology of inflammatory disorders. Accordingly, the interaction between the RAS and the dopaminergic system has been studied in the context of inflammation of the central nervous system (CNS), kidney, and intestine, where they exert antagonistic actions in the regulation of the immune system. In this review, we summarized, integrated, and discussed the cross talk of the dopaminergic system and the RAS in the regulation of inflammatory pathologies, including neurodegenerative disorders, such as Parkinson’s disease. We analyzed the molecular mechanisms underlying the interaction between both systems in the CNS and in systemic pathologies. Moreover, we also analyzed the impact of the commensal microbiota in the regulation of RAS and dopaminergic system and how it is involved in inflammatory disorders. Furthermore, we summarized the therapeutic approaches that have yielded positive results in preclinical or clinical studies regarding the use of drugs targeting the RAS and dopaminergic system for the treatment of inflammatory conditions. Further understanding of the molecular and cellular regulation of the RAS-dopaminergic cross talk should allow the formulation of new therapies consisting of novel drugs and/or repurposing already existing drugs, alone or in combination, for the treatment of inflammatory disorders.

Anatabine ameliorates intestinal inflammation and reduces the production of pro-inflammatory factors in a dextran sulfate sodium mouse model of colitis

Background

Inflammatory bowel disease (IBD) is the collective term for chronic immune-mediated diseases of unknown, multifactorial etiology, arising from the interplay between genetic and environmental factors and including two main disease manifestations: ulcerative colitis (UC) and Crohn’s disease. In the last few decades, naturally occurring alkaloids have gained interest because of their substantial anti-inflammatory effects in several animal models of disease. Studies on mouse models of IBD have demonstrated the anti-inflammatory action of the main tobacco alkaloid, nicotine. In addition, anatabine, a minor tobacco alkaloid also present in peppers, tomato, and eggplant presents anti-inflammatory properties in vivo and in vitro. In this study, we aimed to evaluate the anti-inflammatory properties of nicotine and anatabine in a dextran sulfate sodium (DSS) mouse model of UC.

Results

Oral administration of anatabine, but not nicotine, reduced the clinical symptoms of DSS-induced colitis. The result of gene expression analysis suggested that anatabine had a restorative effect on global DSS-induced gene expression profiles, while nicotine only had limited effects. Accordingly, MAP findings revealed that anatabine reduced the colonic abundance of DSS-associated cytokines and increased IL-10 abundance.

Conclusions

Our results support the amelioration of inflammatory effects by anatabine in the DSS mouse model of UC, and suggest that anatabine constitutes a promising therapeutic agent for IBD treatment.

The reduction of DSS-induced colitis severity in mice exposed to cigarette smoke is linked to immune modulation and microbial shifts

Exposure to cigarette smoke (CS) causes detrimental health effects, increasing the risk of cardiovascular, pulmonary diseases and carcinogenesis in exposed individuals. The impact of CS on Inflammatory Bowel Disease (IBD) has been established by a number of epidemiological and clinical studies. In fact, CS is associated with a higher risk of developing Crohn’s disease (CD) while inversely correlates with the development, disease risks, and relapse rate of ulcerative colitis (UC). To investigate the effect of CS exposure on experimental colitis, we performed a comprehensive and integrated comparative analysis of colon transcriptome and microbiome in mice exposed to dextran sodium sulfate (DSS) and CS. Colon transcriptome analysis revealed that CS downregulated specific pathways in a concentration-dependent manner, affecting both the inflammatory state and composition of the gut microbiome. Metagenomics analysis demonstrated that CS can modulate DSS-induced dysbiosis of specific bacterial genera, contributing to resolve the inflammation or accelerate recovery. The risks of smoking far outweigh any possible benefit, thus smoking cessation must always be encouraged because of its significant health benefits. However, the inverse association between active smoking and the development of UC cannot be ignored and the present study lays the foundation for investigating potential molecular mechanisms responsible for the attenuation of colitis by certain compounds of tobacco when decoupled from combustion.

Natural Products: Experimental Efficient Agents for Inflammatory Bowel Disease Therapy

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Inflammatory bowel disease (IBD) is a chronic, elusive disorder resulting in relapsing inflammation of intestine with incompletely elucidated etiology, whose two representative forms are ulcerative colitis (UC) and Crohn’s disease (CD). Accumulating researches have revealed that the individual genetic susceptibility, environmental risk elements, intestinal microbial flora, as well as innate and adaptive immune system are implicated in the pathogenesis and development of IBD. Despite remarkable progression of IBD therapy has been achieved by chemical drugs and biological therapies such as aminosalicylates, corticosteroids, antibiotics, anti-tumor necrosis factor (TNF)-α, anti-integrin agents, etc., healing outcome still cannot be obtained, along with inevitable side effects. Consequently, a variety of researches have focused on exploring new therapies, and found that natural products (NPs) isolated from herbs or plants may serve as promising therapeutic agents for IBD through antiinflammatory, anti-oxidant, anti-fibrotic and anti-apoptotic effects, which implicates the modulation on nucleotide- binding domain (NOD) like receptor protein (NLRP) 3 inflammasome, gut microbiota, intestinal microvascular endothelial cells, intestinal epithelia, immune system, etc. In the present review, we will summarize the research development of IBD pathogenesis and current mainstream therapy, as well as the therapeutic potential and intrinsic mechanisms of NPs in IBD.

Nutritional Support and Probiotics as a Potential Treatment of IBD

The pathogenesis of inflammatory bowel disease (IBD) remains unknown. However, there is growing evidence that the increase in the overall incidence of IBD relates to the improvement of sanitary and hygienic conditions of the society leading to lower exposure to both bacterial and parasitic infections. IBD is incurable and characterized by alternating periods of exacerbation and remission of symptoms. Therefore, the main goal of treatment strategies in IBD patients is the most effective maintenance of clinical and endoscopic remission, which does allow patients to function normally for a significant part of life. Taking into account the evidence from different areas, there is a strong rationale supporting the concept that bacteria are important in gut inflammation and that probiotic bacteria may modulate the host-microbe interaction in a way that is directly beneficial to IBD patients along with nutritional support. In this review, we focus on the potential role of gastrointestinal microbiota in the pathogenesis of IBD and the possible value of probiotics, prebiotics, and symbiotics as well as nutritional support in the treatment of IBD.

Experimental colitis reduces microglial cell activation in the mouse brain without affecting microglial cell numbers

Inflammatory bowel disease (IBD) patients frequently suffer from anxiety disorders and depression, indicating that altered gut-brain axis signalling during gastrointestinal inflammation is a risk factor for psychiatric disease. Microglia, immune cells of the brain, is thought to be involved in a number of mental disorders, but their role in IBD is largely unknown. In the current work, we investigated whether colitis induced by dextran sulphate sodium (DSS), a murine model of IBD, alters microglial phenotypes in the brain. We found that colitis caused a reduction of Iba-1 and CD68 immunoreactivity, microglial activation markers, in specific brain regions of the limbic system such as the medial prefrontal cortex (mPFC), while other areas remained unaffected. Flow cytometry showed an increase of monocyte-derived macrophages during colitis and gene expression analysis in the mPFC showed pronounced changes of microglial markers including cluster of differentiation 86 (CD86), tumour necrosis factor-α, nitric oxide synthase 2, CD206 and chitinase-like protein 3 consistent with both M1 and M2 activation. Taken together, these findings suggest that experimental colitis-induced inflammation is propagated to the brain altering microglial function.

Therapeutic effect of gold nanoparticles on DSS-induced ulcerative colitis in mice with reference to interleukin-17 expression

Ulcerative colitis (UC) is among the most challenging human diseases. Nanotechnology has incontestable promising outcomes in inflammatory bowel diseases. This study aimed to investigate the therapeutic effect of naked gold nanoparticles (AuNPs) on dextran sodium sulphate (DSS) induced ulcerative colitis in mice. We also examined the expression of interleukin-17 (IL-17) following AuNPs treatment. Mice were randomly divided into control, DSS and DSS+ AuNPs groups. Severity of colitis was assessed by disease activity index (DAI) measurement. At the end of the experiment, the final body weights were recorded. The colon was dissected and processed for histopathological examinations by light and electron microscopes. Colon homogenates were prepared for assay of tissue malondialdehyde (MDA) and real-time PCR analysis of IL-17A. Immunohistochemical localization of IL-17A was carried out. Scanning electron microscopy (SEM) and Energy Dispersive X-ray (EDX) detector were used to detect the presence of AuNPs in the colonic tissue of DSS+ AuNPs groups. Our results showed that AuNPs effectively targeted the colonic tissue, and reduced changes induced by DSS. The underlying mechanisms could be related to anti-oxidant effect (as evident by decreasing tissue MDA) and anti-inflammatory potential of AuNPs. Our study draws attention to as a novel therapeutic strategy for treating UC.

Nitric oxide in the gastrointestinal tract: opportunities for drug development

Nitric oxide (NO) plays important roles in gastrointestinal mucosal defence, as well as in the pathogenesis of several gastrointestinal diseases (e.g. irritable bowel syndrome and inflammatory bowel disease). The potent cytoprotective effects of NO have been demonstrated in a range of animal models. However, in some disease states, inhibition of NO synthesis is beneficial. Several attempts have been made to develop drugs for ulcerative and/or inflammatory disorders of the gastrointestinal tract, with varying degrees of success. Covalently linking a NO-releasing group to non-steroidal anti-inflammatory drugs or to drugs used in the treatment of inflammatory bowel disease and irritable bowel syndrome has shown some benefit, although no drug of this type has yet been fully developed. LINKED ARTICLES: This article is part of a themed section on Nitric Oxide 20 Years from the 1998 Nobel Prize. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.2/issuetoc.

Modulating the conformation of the TIR domain by a neoteric MyD88 inhibitor leads to the separation of GVHD from GVT

Graft-versus-host disease (GVHD) remains the least curable complication after allogeneic bone marrow transplantation (BMT). Myeloid differentiation factor 88 (MyD88) is an adaptor molecule critically involved in the toll-like receptor (TLR) signaling pathway. The Toll/IL-1 receptor (TIR) domains of MyD88 and TLR are interactional modules responsible for sorting and signaling via direct or indirect TIR-TIR interactions, which can contribute to all phases of GVHD progression. Here, we describe the mechanisms of the novel MyD88 inhibitor, TJ-M2010-5, and the discovery of its immunosuppressive properties in the context of GVHD and the graft-versus-tumor (GVT) effect in a fully MHC-mismatched murine model. TJ-M2010-5 potentially interrupted the conformation of the TIR domain through its predicted DD loops, BB loops, and Poc site, and inhibited the homodimerization of MyD88, the LPS-stimulated activation of dendritic cells, and the priming of donor allogeneic T cell proliferation in a dose-dependent manner. Oral administration of TJ-M2010-5 ameliorated the inflammatory environment, decreased the number of apoptotic cells, increased tissue repair in GVHD target organs, and suppressed lethal GVHD. Further, protection against GVHD by TJ-M2010-5 did not abrogate a GVT effect against SP2/0, a myeloma cell line. Our data define the mechanisms of actions and provide novel insight into the potential clinical uses of TJ-M2010-5 for GVHD prevention.

N-Methylcytisine Ameliorates Dextran-Sulfate-Sodium-Induced Colitis in Mice by Inhibiting the Inflammatory Response

This study aimed to investigate the anti-inflammatory effects of N-methylcytisine (NMC) in a dextran sulfate sodium (DSS)-induced colitis model and explore its possible mechanisms. Experimental colitis was induced by administering the mice with 5% DSS for 7 days. Different doses of NMC (1, 4 and 16 mg/kg) and 5-aminosalicylic acid (100 mg/kg) were given orally once every day for 7 days. The protective effect of NMC was evaluated using the disease activity index, colon length and results of histopathological examination. The possible mechanisms of NMC were explored by evaluating the expression levels of tumour necrosis factor-α, interleukin-1β and interleukin-6 (IL-6) using ELISA and analysing the protein expression levels of nuclear factor (NF)-κB p65, p-NF-κB p65, p-IκB, IκB, IκB kinase (IKK) and p-IKK using western blots. Results demonstrated that the oral administration of NMC attenuated the DSS-induced clinical symptoms and pathological damage. In addition, NMC treatment significantly reduced myeloperoxidase activity and level of pro-inflammatory cytokines. Further studies revealed that NMC blocked the activation of NF-κB by inhibiting IκB and IKK phosphorylation. These findings suggested that NMC exerts anti-inflammatory effects on DSS-induced colitis, and its mechanism may be related to the suppression of NF-κB activation. Thus, NMC may have potential therapeutic value in the treatment of colitis.