Understanding inflammatory bowel disease via immunogenetics

The molecular subtypes of autoimmune diseases

Autoimmune diseases (ADs) are characterized by their complexity and a wide range of clinical differences. Despite patients presenting with similar symptoms and disease patterns, their reactions to treatments may vary. The current approach of personalized medicine, which relies on molecular data, is seen as an effective method to address the variability in these diseases. This review examined the pathologic classification of ADs, such as multiple sclerosis and lupus nephritis, over time. Acknowledging the limitations inherent in pathologic classification, the focus shifted to molecular classification to achieve a deeper insight into disease heterogeneity. The study outlined the established methods and findings from the molecular classification of ADs, categorizing systemic lupus erythematosus (SLE) into four subtypes, inflammatory bowel disease (IBD) into two, rheumatoid arthritis (RA) into three, and multiple sclerosis (MS) into a single subtype. It was observed that the high inflammation subtype of IBD, the RA inflammation subtype, and the MS "inflammation & EGF" subtype share similarities. These subtypes all display a consistent pattern of inflammation that is primarily driven by the activation of the JAK-STAT pathway, with the effective drugs being those that target this signaling pathway. Additionally, by identifying markers that are uniquely associated with the various subtypes within the same disease, the study was able to describe the differences between subtypes in detail. The findings are expected to contribute to the development of personalized treatment plans for patients and establish a strong basis for tailored approaches to treating autoimmune diseases.

New insight in treating autoimmune diseases by targeting autophagy

Autophagy is a highly conserved biological process in eukaryotes, which degrades cellular misfolded proteins, damaged organelles and invasive pathogens in the lysosome-dependent manner. Autoimmune diseases caused by genetic elements, environments and aberrant immune responses severely impact patients' living quality and even threaten life. Recently, numerous studies have reported autophagy can regulate immune responses, and play an important role in autoimmune diseases. In this review, we summarised the features of autophagy and autophagy-related genes, enumerated some autophagy-related genes involved in autoimmune diseases, and further overviewed how to treat autoimmune diseases through targeting autophagy. Finally, we outlooked the prospect of relieving and curing autoimmune diseases by targeting autophagy pathway.

The histamine H4 receptor antagonist 1-[(5-chloro-2,3-dihydro-1-benzofuran-2-yl)methyl]-4-methyl-piperazine(LINS01007) prevents the development of DSS-induced colitis in mice

Ulcerative colitis (UC) is a chronic inflammatory bowel disease with growing incidence worldwide. Our group reported the compound 5-choro-1-[(2,3-dihydro-1-benzofuran-2-yl)methyl]piperazine (LINS01007) as H4R antagonist (pKi 6.2) and therefore the effects and pharmacological efficacy on a DSS-induced mice model of UC were assessed in this work. Experimental acute colitis was induced in male BALB/c mice (n = 5-10) by administering 3 % DSS in the drinking water for six days. The test compound LINS01007 was administered daily i.p. (5 mg/kg) and compared to control group without treatment. Body weight, water and food consumption, and the presence of fecal blood were monitored during 7-day treatment period. The levels of inflammatory markers (PGE2, COX-2, IL-6, NF-κB and STAT3) were also analyzed. Animals subjected to the acute colitis protocol showed a reduction in water and food intake from the fourth day (p < 0.05) and these events were prevented by LINS01007. Histological signs of edema, hyperplasia and disorganized intestinal crypts, as well as neutrophilic infiltrations, were found in control mice while these findings were significantly reduced in animals treated with LINS01007. Significant reductions in the levels of PGE2, COX-2, IL-6, NF-κB and STAT3 were observed in the serum and tissue of treated animals. The results demonstrated the significant effects of LINS01007 against DSS-induced colitis, highlighting the potential of H4R antagonism as promising treatment for this condition.

Label-free electrochemical biosensor for direct detection of Oncostatin M (OSM) inflammatory bowel diseases (IBD) biomarker in human serum

Oncostatin M (OSM) is an interleukin-6 (IL-6) member family cytokine implicated in the pathogenesis of chronic diseases including inflammatory bowel disease (IBD). OSM is a novel diagnostic biomarker over-expressed in the serum of IBD patients. This paper reports on the first electrochemical OSM immunosensor, developed using a multistep fabrication process aimed at covalently immobilizing OSM antibodies on a mixed self-assembled monolayer coated gold working electrode. Cyclic voltammetry, atomic force microscopy (AFM), IR spectroscopy and optical characterizations were used to validate the sensor functionalization protocol. Electrochemical impedance spectroscopy (EIS) measurements were performed to assess the reliability of the immunosensor preparation and to verify the antibody-antigen complexes formation. The label-free immunosensor showed high sensitivity identifying OSM at clinically relevant concentrations (37-1000 pg mL-1) with low detection limit of 2.86 pg mL-1. Both sensitivity and selectivity of the proposed immunosensor were also demonstrated in human serum in the presence of interfering biomarkers, making it an innovative potential platform for the OSM biomarker detection in IBD patients' serum.

Inflammatory bowel disease and allergic diseases: A Mendelian randomization study

BACKGROUND

Inflammatory bowel disease (IBD) and allergic diseases possess similar genetic backgrounds and pathogenesis. Observational studies have shown a correlation, but the exact direction of cause and effect remains unclear. The aim of this Mendelian randomization (MR) study is to assess bidirectional causality between inflammatory bowel disease and allergic diseases.

METHOD

We comprehensively analyzed the causal relationship between inflammatory bowel disease (IBD), Crohn's disease (CD), ulcerative colitis (UC) and allergic disease (asthma, Hay fever, and eczema) as a whole, allergic conjunctivitis (AC), atopic dermatitis (AD), allergic asthma (AAS), and allergic rhinitis (AR) by performing a bidirectional Mendelian randomization study using summary-level data from genome-wide association studies. The analysis results mainly came from the random-effects model of inverse variance weighted (IVW-RE). In addition, multivariate Mendelian randomization (MVMR) analysis was conducted to adjust the effect of body mass index (BMI) on the instrumental variables.

RESULTS

The IVW-RE method revealed that IBD genetically increased the risk of allergic disease as a whole (OR = 1.03, 95% CI = 1.01-1.04, fdr.p = .015), AC (OR = 1.04, 95% CI = 1.01-1.06, fdr.p = .011), and AD (OR = 1.06, 95% CI = 1.02-1.09, fdr.p = .004). Subgroup analysis further confirmed that CD increased the risk of allergic disease as a whole (OR = 1.02, 95% CI = 1.00-1.03, fdr.p = .031), AC (OR = 1.03, 95% CI = 1.01-1.05, fdr.p = .012), AD (OR = 1.06, 95% CI = 1.02-1.09, fdr.p = 2E-05), AAS (OR = 1.05, 95% CI = 1.02-1.08, fdr.p = .002) and AR (OR = 1.03, 95% CI = 1.00-1.07, fdr.p = .025), UC increased the risk of AAS (OR = 1.02, 95% CI = 0.98-1.07, fdr.p = .038). MVMR results showed that after taking BMI as secondary exposure, the causal effects of IBD on AC, IBD on AD, CD on allergic disease as a whole, CD on AC, CD on AD, CD on AAS, and CD on AR were still statistically significant. No significant association was observed in the reverse MR analysis.

CONCLUSION

This Mendelian randomized study demonstrated that IBD is a risk factor for allergic diseases, which is largely attributed to its subtype CD increasing the risk of AC, AD, ASS, and AR. Further investigations are needed to explore the causal relationship between allergic diseases and IBD.

Molecular Foundations of Inflammatory Diseases: Insights into Inflammation and Inflammasomes

Inflammatory diseases are a global health problem affecting millions of people with a wide range of conditions. These diseases, including inflammatory bowel disease (IBD), rheumatoid arthritis (RA), osteoarthritis (OA), gout, and diabetes, impose a significant burden on patients and healthcare systems. A complicated interaction between genetic variables, environmental stimuli, and dysregulated immune responses shows the complex biological foundation of various diseases. This review focuses on the molecular mechanisms underlying inflammatory diseases, including the function of inflammasomes and inflammation. We investigate the impact of environmental and genetic factors on the progression of inflammatory diseases, explore the connection between inflammation and inflammasome activation, and examine the incidence of various inflammatory diseases in relation to inflammasomes.

A family with ulcerative colitis maps to 7p21.1 and comprises a region with regulatory activity for the aryl hydrocarbon receptor gene

We have mapped a locus on chromosome 7p22.3-7p15.3 spanning a 22.4 Mb region for ulcerative colitis (UC) by whole genome linkage analyses of a large Danish family. The family represent three generations with UC segregating as an autosomal dominant trait with variable expressivity. The whole-genome scan resulted in a logarithm of odds score (LOD score) of Z = 3.31, and a whole genome sequencing (WGS) of two affected excluded disease-causing mutations in the protein coding genes. Two rare heterozygote variants, rs182281985:G>A and rs541426369:G>A, both with low allele frequencies (MAF A:0.0001, gnomAD ver3.1.2), were found in clusters of ChiP-seq transcription factors binding sites close to the AHR (aryl hydrocarbon receptor) gene and the UC associated SNP rs1077773:G>A. Testing the two SNPs in a promoter reporter assay for regulatory activity revealed that rs182281985:G>A influenced the AHR promoter. These results suggest a regulatory region that include rs182281985:G>A close to the UC GWAS SNP rs1077773:G>A and further demonstrate evidence that the AHR gene on the 7p-tel region is a candidate susceptible gene for UC.

Effect of minocycline, methyl prednisolone, or combination treatment on the colonic bacterial population in a state of colonic inflammation using the murine dextran sulfate sodium model

BACKGROUND

Several reports demonstrated anti-inflammatory properties of minocycline in various inflammatory disorders including colitis. We have experimental evidence suggesting synergistic anti-inflammatory effect of minocycline with methyl prednisolone in reducing colitis severity in mice, but if this effect is in part related to modulating the composition of colonic microbiota is still unknown.

METHODS

the effect of vehicle (V), minocycline (M), methyl prednisolone (MP), or combination (C) regimen on the composition of the microbiota of mice in a state of colon inflammation compared to untreated (UT) healthy mice was determined using 16s metagenomic sequencing, and the taxonomic and functional profiles were summarized.

RESULTS

Overall, the bacterial flora from the phylum Firmicutes followed by Bacteroidota were found to be predominant in all the samples. However, the composition of Firmicutes was decreased relatively in all the treatment groups compared to UT group. A relatively higher percentage of Actinobacteriota was observed in the samples from the C group. At the genus level, Muribaculaceae, Bacteroides, Bifidobacterium, and Lactobacillus were found to be predominant in the samples treated with both drugs (C). Whereas "Lachnospiraceae NK4A136 group" and Helicobacter in the M group, and Helicobacter in the MP group were found to be predominant. But, in the UT group, Weissella and Staphylococcus were found to be predominant. Eubacterium siraeum group, Clostridia vadinBB60 group, Erysipelatoclostridium and Anaeroplasma genera were identified to have a significant (FDR p < 0.05) differential abundance in V compared to C and UT groups. While at the species level, the abundance of Helicobacter mastomyrinus, Massiliomicrobiota timonensis and uncultured Anaeroplasma were identified as significantly low in UT, C, and M compared to V group. Functional categories related to amino acid, carbohydrate, and energy metabolism, cell motility and cell cycle control were dominated overall across all the samples. Methane metabolism was identified as an enriched pathway. For the C group, "Colitis (decrease)" was among the significant (p = 1.81E-6) associations based on the host-intrinsic taxon set.

CONCLUSION

Combination regimen of minocycline plus methyl prednisolone produces a synergistic anti-inflammatory effect which is part related to alternation in the colonic microbiota composition.

Impact of Microbiome-Brain Communication on Neuroinflammation and Neurodegeneration

The gut microbiome plays a pivotal role in maintaining human health, with numerous studies demonstrating that alterations in microbial compositions can significantly affect the development and progression of various immune-mediated diseases affecting both the digestive tract and the central nervous system (CNS). This complex interplay between the microbiota, the gut, and the CNS is referred to as the gut-brain axis. The role of the gut microbiota in the pathogenesis of neurodegenerative diseases has gained increasing attention in recent years, and evidence suggests that gut dysbiosis may contribute to disease development and progression. Clinical studies have shown alterations in the composition of the gut microbiota in multiple sclerosis patients, with a decrease in beneficial bacteria and an increase in pro-inflammatory bacteria. Furthermore, changes within the microbial community have been linked to the pathogenesis of Parkinson's disease and Alzheimer's disease. Microbiota-gut-brain communication can impact neurodegenerative diseases through various mechanisms, including the regulation of immune function, the production of microbial metabolites, as well as modulation of host-derived soluble factors. This review describes the current literature on the gut-brain axis and highlights novel communication systems that allow cross-talk between the gut microbiota and the host that might influence the pathogenesis of neuroinflammation and neurodegeneration.

Effect of Carbamylated Erythropoietin in a Chronic Model of TNBS-Induced Colitis

BACKGROUND

Inflammatory bowel disease (IBD) is a public health issue with a growing prevalence, which can be divided into two phenotypes, namely Crohn's disease (CD) and ulcerative colitis (UC). Currently, used therapy is based only on symptomatic and/or palliative pharmacological approaches. These treatments seek to induce and maintain remission of the disease and ameliorate its secondary effects; however, they do not modify or reverse the underlying pathogenic mechanism. Therefore, it is essential to investigate new potential treatments. Carbamylated erythropoietin (cEPO) results from the modification of the Erythropoietin (EPO) molecule, reducing cardiovascular-related side effects from the natural erythropoiesis stimulation. cEPO has been studied throughout several animal models, which demonstrated an anti-inflammatory effect by decreasing the production of several pro-inflammatory cytokines.

AIM

This study aimed to evaluate the efficacy and safety of cEPO in a chronic TNBS-induced colitis model in rodents.

METHODS

Experimental colitis was induced by weekly intrarectal (IR) administrations of 1% TNBS for 5 weeks in female CD-1 mice. Then, the mice were treated with 500 IU/kg/day or 1000 IU/kg/day of cEPO through intraperitoneal injections for 14 days.

RESULTS

cEPO significantly reduced the concentration of alkaline phosphatase (ALP), fecal hemoglobin, tumor necrosis factor (TNF)-α, and interleukin (IL)-10. Also, it demonstrated a beneficial influence on the extra-intestinal manifestations, with the absence of significant side effects of its use.

CONCLUSION

Considering the positive results from cEPO in this experiment, it may arise as a new possible pharmacological approach for the future management of IBD.

The causal effect of inflammatory bowel disease on diffuse large B-cell lymphoma: two-sample Mendelian randomization study

Background

It has been reported that inflammatory bowel disease (IBD) is associated with an increased risk of malignancies, including lymphoma. A number of large observational studies have been devoted to exploring the causal link between IBD and malignant lymphoma. However, no consensus exists on whether there is a causal relationship between IBD and malignant lymphoma.

Methods

The summary dataset of the IBD and lymphoma genome-wide association studies (GWAS) was obtained from the OPEN GWAS website. Single-nucleotide polymorphisms (SNPs) were selected as genetic instrumental variants (IVs) for fulling P < 5 × 10-8 and linkage disequilibrium (LD) of r2 = 0.001 in the IBD GWAS. The proxy SNPs with LD of r2 > 0.8 were identified. Palindromic SNPs and outlier SNPs were excluded. The assessments of sensitivity employed the Cochran's Q test, Mendelian randomization (MR)-Egger intercept test, and leave-one-out analysis.

Results

The MR analysis results proved the causality of IBD on diffuse large B-cell lymphoma (DLBCL). The risk of developing DLBCL is increased by 28.6% in patients with IBD [odds ratio (OR)IVW = 1.286, 95% confidence interval (CI) 1.066-1.552, P = 0.009]. The results of the subgroup analysis showed that Crohn's disease (ORIVW = 1.218, 95% CI 1.030-1.441, P = 0.021) rather than ulcerative colitis (ORIVW = 1.206, 95% CI 0.984-1.478, P = 0.072) had a causal effect on DLBCL. No horizontal and directional pleiotropy was observed in the MR studies.

Conclusions

The above MR study concluded that IBD itself is causally responsible for DLBCL, especially Crohn's disease. Further investigations are needed to elucidate the mechanism underlying this direct causal link.

Oral intake of titanium dioxide nanoparticles affect the course and prognosis of ulcerative colitis in mice: involvement of the ROS-TXNIP-NLRP3 inflammasome pathway

BACKGROUND

Titanium dioxide (TiO₂), no matter in nanoscale or micron sizes, has been widely used in food industry as additives for decades. Given the potential impact of TiO₂ on the gastrointestinal epithelial and parenchymal cells, including goblet cells, the public consumers may suffer the risk of diseases caused by its widespread dissemination in food products. We therefore set out to investigate the impact of TiO₂ NPs on the course and prognosis of ulcerative colitis by oral gavaging TiO₂ NPs at the doses levels of 0, 30, 100, and 300 mg/kg during the induction (7 days, from day 1 to day 7) and recovery (10 days, from day 8 to day 17) phases of colitis in mice.

RESULTS

The ulcerative colitis (UC) disease model was established by administrating of 2.5% dextran sulfate sodium (DSS) solution. Our results show that TiO₂ NPs significantly enhanced the severity of DSS-induced colitis, decreased the body weight, increased the disease activity index (DAI) and colonic mucosa damage index (CMDI) scores, shortened the colonic length, increased the inflammatory infiltration in the colon. The most significant changes occurred in the low dose (30 mg/kg) group of TiO₂ NPs exposure during the development phase of UC and the high dose (300 mg/kg) group of TiO₂ NPs during UC self-healing phase. Increased reactive oxygen species (ROS) level and upregulation of anti-oxidant enzymes including total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-PX) and catalase (CAT), demonstrate that the TiO₂ NP exposure has triggered oxidative stress in mice. Moreover, the upregulation of caspase-1 mRNA and increased expression of thioredoxin interacting protein (TXNIP) further demonstrate the involvement of the ROS-TXNIP-NLR family pyrin domain containing 3 (NLRP3) inflammasome pathway in aggravating the development of UC.

CONCLUSION

Oral intake of TiO₂ NPs could affect the course of acute colitis in exacerbating the development of UC, prolonging the UC course and inhibiting UC recovery.

Lunasin reduces the susceptibility of IL-10 deficient mice to inflammatory bowel disease and modulates the activation of the NLRP3 inflammasome

Inflammatory bowel disease (IBD) is a chronic inflammatory condition that can cause severe damage to the gastrointestinal tract leading to lower quality of life and productivity. Our goal was to investigate the protective effect of the soy peptide lunasin in an in vivo model of susceptibility to IBD and to identify the potential mechanism of action in vitro. In IL-10 deficient mice, oral administration of lunasin reduced the number and frequency of mice exhibiting macroscopic signs of susceptibility to inflammation and significantly decreased levels of the pro-inflammatory cytokines TNF-α, IL-1β, IL-6, and IL-18 by up to 95%, 90%, 90%, and 47%, respectively, in different sections of the small and large intestines. Dose-dependent decrease of caspase-1, IL-1β, and IL-18 in LPS-primed and ATP-activated THP-1 human macrophages demonstrated the ability of lunasin to modulate the NLRP3 inflammasome. We demonstrated that lunasin can decrease susceptibility to IBD in genetically susceptible mice by exerting anti-inflammatory properties.

Selenoprotein W Ameliorates Experimental Colitis and Promotes Intestinal Epithelial Repair

Selenoprotein W (Selenow) is a ~9 kDa selenoprotein suggested to play a beneficial role in resolving inflammation. However, the underlying mechanisms are poorly understood. SELENOW expression in the human GI tract using ScRNAseq Gut Cell Atlas and Gene Expression Omnibus (GEO) databases revealed its expression in the small intestine and colonic epithelial, endothelial, mesenchymal, and stem cells and correlated with a protective effect in ulcerative colitis patients. Selenow KO mice treated with 4% dextran sodium sulfate (DSS) showed exacerbated acute colitis, with greater weight loss, shorter colons, and increased fecal occult blood compared to the WT counterparts. Selenow KO mice expressed higher colonic Tnfα, increased Tnfα+ macrophages in the colonic lamina propria, and exhibited loss in epithelial barrier integrity and decreased zonula occludens 1 (Zo-1) expression following DSS treatment. Expression of epithelial cellular adhesion marker (EpCam), yes-associated protein 1 (Yap1), and epidermal growth factor receptor (Egfr) were decreased along with CD24lo cycling epithelial cells in Selenow KO mice. Colonic lysates and organoids confirmed a crosstalk between Egfr and Yap1 that was regulated by Selenow. Overall, our findings suggest Selenow expression is key for efficient resolution of inflammation in experimental colitis that is mediated through the regulation of Egfr and Yap1.

Genetic and Epigenetic Etiology of Inflammatory Bowel Disease: An Update

Inflammatory bowel disease (IBD) is a chronic disease with periods of exacerbation and remission of the disease. The etiology of IBD is not fully understood. Many studies point to the presence of genetic, immunological, environmental, and microbiological factors and the interactions between them in the occurrence of IBD. The review looks at genetic factors in the context of both IBD predisposition and pharmacogenetics.

Dextran sodium sulfate alters antioxidant status in the gut affecting the survival of Drosophila melanogaster

Inflammatory bowel disease (IBD) is a group of disorders characterized by chronic inflammation in the intestine. Several studies confirmed that oxidative stress induced by an enormous amount of reactive free radicals triggers the onset of IBD. Currently, there is an increasing trend in the global incidence of IBD and it is coupled with a lack of adequate long-term therapeutic options. At the same time, progress in research to understand the pathogenesis of IBD has been hampered due to the absence of adequate animal models. Currently, the toxic chemical Dextran Sulfate Sodium (DSS) induced gut inflammation in rodents is widely perceived as a good model of experimental colitis or IBD. Drosophila melanogaster, a genetic animal model, shares ~ 75% sequence similarity to genes causing different diseases in humans and also has conserved digestion and absorption features. Therefore, in the current study, we used Drosophila as a model system to induce and investigate DSS-induced colitis. Anatomical, biochemical, and molecular analyses were performed to measure the levels of inflammation and cellular disturbances in the gastrointestinal (GI) tract of Drosophila. Our study shows that DSS-induced inflammation lowers the levels of antioxidant molecules, affects the life span, reduces physiological activity and induces cellular damage in the GI tract mimicking pathophysiological features of IBD in Drosophila. Such a DSS-induced Drosophila colitis model can be further used for understanding the molecular pathology of IBD and screening novel drugs.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-022-03349-2.

Preventive Effect of Vitamin C on Dextran Sulfate Sodium (DSS)-Induced Colitis via the Regulation of IL-22 and IL-6 Production in Gulo(−/−) Mice

Reactive oxygen species (ROS), which are exceptionally high in IBD lesions, are known to cause abnormal immune responses to inflammatory reactions in inflammatory bowel diseases (IBD) through damage to the intestinal mucosal linings. Moreover, they are theorized to be an agent of IBD development. Vitamin C is widely known to be an effective antioxidant for its ability to regulate inflammatory responses through its ROS scavenging effect. Therefore, we examined vitamin C’s influence on the development and progression of IBD in Gulo(−/−) mice, which cannot synthesize vitamin C like humans due to a defect in the expression of L-gulono-γ–lactone oxidase, an essential enzyme for vitamin C production. First, we found extensive oxidative stress and an inflammation increase in the colon of vitamin C-insufficient Gulo(−/−) mice. We also found decreased IL-22 production and NKp46(+) cell recruitment and the impaired activation of the p38MAPK pathway. Additionally, comparing vitamin C-insufficient Gulo(−/−) mice to vitamin C-sufficient Gulo(−/−) mice and wild-type mice, the insufficient group faced a decrease in mucin-1 expression, accompanied by an increase in IL-6 production, followed by the activation of the STAT3 and Akt pathways. The results suggest that vitamin C insufficiency induces severe colitis, meaning vitamin C could also take on a preventative role by regulating the production of cytokines and the induction of inflammation.

Pharmacological Management of Inflammatory Bowel Disease: a Century of Expert Opinions in Cecil Textbook of Medicine

BACKGROUND

Advances in drug therapy for inflammatory bowel disease (IBD) [Crohn disease and ulcerative colitis (UC)] have contributed to a decrease in the severity of these chronic and disabling conditions.

STUDY QUESTION

What are the milestones of the changes in the expert approach to the pharmacological management of IBD in the past century?

STUDY DESIGN

To determine the changes in the experts' approach to the management of regional ileitis and UC, as presented in a widely used textbook in the United States.

DATA SOURCES

The chapters presenting the management of IBD in the 26 editions of Cecil Textbook of Medicine published from 1927 through 2020.

RESULTS

No specific interventions existed from 1927 through 1942. The pharmacological management of IBD has had 3 slightly overlapping eras starting in 1943. During the first period (1943-1951), the medical management relied on antibiotics, primarily sulfonamides and chloramphenicol. In the second (1955-75), experts recommended the use of adrenocorticotropic hormone or corticosteroids and 5-aminosalicylate. In the third era, which commenced in 1979 and is continuing to date, the pharmacological interventions have been expanded and refined to include 5 main drug classes, 5-aminosalicylates (sulfasalazine, mesalamine, and olsalazine), corticosteroids (prednisone and budesonide), immunomodulators (azathioprine, 6-mercaptopurine, cyclosporine, and tofacitinib), biologics (infliximab adalimumab certolizumab pegol, and natalizumab), and antibiotics (metronidazole and ciprofloxacin). A consensus exists that the monoclonal antibodies again tumor necrosis factor alpha are cost-effective for induction and maintenance of clinical remission in both UC (golimumab) and Crohn disease (certolizumab pegol). The newer agents ustekinumab (a monoclonal antibody to the interleukin p40 subunit) and vedolizumab (a monoclonal antibody to the homing receptor integrin complex) have also performed well.

CONCLUSIONS

The pharmacological management of IBD has been the focus of intense research and development in the past 60 years. The pillars of drug treatment have been 5-aminosalicylates and corticosteroids. Recent pharmacological innovations (immunomodulators and biologicals) constitute an encouraging paradigm shift in the treatment of UC and Crohn disease.

Anti-Inflammatory Effect of Topiramate in a Chronic Model of TNBS-Induced Colitis

Inflammatory bowel disease (IBD) is characterized by a chronic and relapsing inflammatory response in the gastrointestinal tract, resulting in severe symptoms such as abdominal pain, vomiting, diarrhea, bloody stools, and weight loss. Currently, there is no cure, and the pharmacological treatment includes drugs that induce and keep the patient in remission, not reversing the underlying pathogenic mechanism. These therapies, in the long term, may cause various side effects and complications, which has increased the need to investigate new, more effective, and safer pharmacological approaches. In preclinical studies, topiramate has demonstrated a potential anti-inflammatory effect by inhibiting the production of several pro-inflammatory cytokines. This study aimed to investigate the effect of topiramate in a chronic TNBS-induced colitis model in rodents. Experimental colitis was induced by four intrarectal administrations of 1% TNBS in female CD-1 mice. Topiramate 10 and 20 mg were administered intraperitoneally for 14 days. Several parameters were evaluated, such as bodyweight, alkaline phosphatase (ALP), fecal hemoglobin, fecal calprotectin, tumor necrosis factor (TNF)-α, and interleukin (IL)-10. Topiramate reduces TNBS-induced colonic damage in a model of chronic experimental colitis and normalizes the stool consistency and anus appearance. Additionally, topiramate significantly reduced the concentration of ALP, fecal hemoglobin, fecal calprotectin, TNF-α, and IL-10, demonstrating it to be a promising pharmacological approach for the treatment of IBD in the future.

Therapeutic Potential of Quercetin Loaded Nanoparticles: Novel Insights in Alleviating Colitis in an Experimental DSS Induced Colitis Model

Oxidative stress is considered the main etiologic factor involved in inflammatory bowel disease (IBD). Integration of nanocarriers for natural therapeutic agents with antioxidant and anti-inflammatory potential is a novel promising candidate for curing IBD. Herein, the colonic antioxidant and anti-inflammatory effects of different concentrations of quercetin nanoparticles (QT-NPs) were evaluated using a dextran sulfate sodium (DSS)-induced colitis model. Following colitis induction, the efficacy and mechanistic actions of QT-NPs were evaluated by assessing lesion severity, molecular aids controlling oxidative stress and inflammatory response, and histopathological and immunohistochemistry examination of colonic tissues. Administration of QT-NPs, especially at higher concentrations, significantly reduced the disease activity index and values of fecal calprotectin marker compared to the colitic group. Colonic oxidant/antioxidant status (ROS, H₂O₂, MDA, SOD, CAT, GPX and TAC) was restored after treatment with higher concentrations of QT-NPs. Moreover, QT-NPs at levels of 20 mg/kg and, to a lesser extent, 15 mg/kg reduced Nrf2 and HO-1 gene expression, which was in line with decreasing the expression of iNOS and COX2 in colonic tissues. Higher concentrations of QT-NPs greatly downregulated pro-inflammatory cytokines; upregulated genes encoding occludin, MUC-2 and JAM; and restored the healthy architectures of colonic tissues. Taken together, these data suggest that QT-NPs could be a promising alternative to current IBD treatments.

Protective effects of Ligularia fischeri root extracts against ulcerative colitis in mice through activation of Bcl-2/Bax signalings

BACKGROUND

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by high levels of proinflammatory cytokines and epithelial barrier dysfunction. The root of Ligularia fischeri (Ledeb.) Turcz. is a traditional Chinese medicinal herb with diverse therapeutic properties, which has been successfully used to treat inflammation-related diseases. However, little is known about its effect and mechanism against UC.

PURPOSE

To investigate the efficacy and mechanism of L. fischeri root extracts against UC.

METHODS

L. fischeri root samples were prepared using the alcohol extraction method and liquid-liquid extraction method. A dextran sodium sulfate-induced UC mouse model and a lipopolysaccharide (LPS)-induced inflammatory cell model were employed in the present study. Cell apoptosis was detected by TUNEL staining, and an enzyme-linked immunosorbent assay was used to quantify the abundance of inflammatory factors in tissues. Hematoxylin and eosin staining and Masson staining were employed to analyze drug toxicity to the liver and kidney. A myeloperoxidase (MPO) assay kit was used to detect neutrophil infiltration in colon tissues. RT-qPCR was then employed to quantify the transcriptional levels of proinflammatory and apoptotic-related genes, while tight junction and apoptosis-related proteins were quantified via western blotting. Gas Chromatography/Mass Spectrometry analysis was then performed to identify the natural compounds in L. fischeri root extracts.

RESULTS

The water decoction extract, methanol extract, and especially the chloroform extract (CE) exerted potent therapeutic effects in UC mice. Similar to the positive control group (5-aminosalicylic acid), oral administration of CE (30, 60, and 90 mg/kg/d) elicited distinct therapeutic effects on UC mice in the medium- and high-dose groups. CE decreased disease activity index, histopathological score, and MPO level significantly, and effectively retained the colon length. Furthermore, CE significantly reduced the levels of proinflammatory cytokines, including interleukin (IL)-1β, IL-6, and tumor necrosis factor-α and enhanced the expression of tight junction proteins, such as zonula occludens (ZO)-1, ZO-2, claudin-1, and occludin, as well as the transcriptional levels of mucins, such as MUC-1 and MUC-2, in UC mice. Notably, CE prevented apoptosis of colonic epithelial cells by up-regulating Bcl-2 and down-regulating Bax. Also, CE inhibited the secretion of pro-inflammatory cytokines and apoptosis in LPS-induced RAW264.7 macrophages via the activation of Bcl-2/Bax signals.

CONCLUSIONS

Collectively, L. fischeri root extracts, especially CE, have obvious therapeutic effects against UC. CE reduces inflammation and protects the intestinal epithelial cells and intestinal epithelial barrier via activation of the Bcl-2/Bax signaling pathway, and may be a promising therapeutic agent for UC treatment.

Chronic Experimental Model of TNBS-Induced Colitis to Study Inflammatory Bowel Disease

Background: Inflammatory bowel disease (IBD) is a world healthcare problem. In order to evaluate the effect of new pharmacological approaches for IBD, we aim to develop and validate chronic trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice. Methods: Experimental colitis was induced by the rectal administration of multiple doses of TNBS in female CD-1 mice. The protocol was performed with six experimental groups, depending on the TNBS administration frequency, and two control groups (sham and ethanol groups). Results: The survival rate was 73.3% in the first three weeks and, from week 4 until the end of the experimental protocol, the mice’s survival remained unaltered at 70.9%. Fecal hemoglobin presented a progressive increase until week 4 (5.8 ± 0.3 µmol Hg/g feces, p < 0.0001) compared with the ethanol group, with no statistical differences to week 6. The highest level of tumor necrosis factor-α was observed on week 3; however, after week 4, a slight decrease in tumor necrosis factor-α concentration was verified, and the level was maintained until week 6 (71.3 ± 3.3 pg/mL and 72.7 ± 3.6 pg/mL, respectively). Conclusions: These findings allowed the verification of a stable pattern of clinical and inflammation signs after week 4, suggesting that the chronic model of TNBS-induced colitis develops in 4 weeks.

Dysbiosis in Inflammatory Bowel Disease: Pathogenic Role and Potential Therapeutic Targets

Microbe-host communication is essential to maintain vital functions of a healthy host, and its disruption has been associated with several diseases, including Crohn's disease and ulcerative colitis, the two major forms of inflammatory bowel disease (IBD). Although individual members of the intestinal microbiota have been associated with experimental IBD, identifying microorganisms that affect disease susceptibility and phenotypes in humans remains a considerable challenge. Currently, the lack of a definition between what is healthy and what is a dysbiotic gut microbiome limits research. Nevertheless, although clear proof-of-concept of causality is still lacking, there is an increasingly evident need to understand the microbial basis of IBD at the microbial strain, genomic, epigenomic, and functional levels and in specific clinical contexts. Recent information on the role of diet and novel environmental risk factors affecting the gut microbiome has direct implications for the immune response that impacts the development of IBD. The complexity of IBD pathogenesis, involving multiple distinct elements, suggests the need for an integrative approach, likely utilizing computational modeling of molecular datasets to identify more specific therapeutic targets.

Oyster (Crassostrea gigas) Extract Attenuates Dextran Sulfate Sodium-Induced Acute Experimental Colitis by Improving Gut Microbiota and Short-Chain Fatty Acids Compositions in Mice

Drugs for inflammatory bowel diseases can be associated with serious side effects, and the development of alternative candidate resources derived from natural products has attracted considerable attention. Oyster extract (OE) derived from Crassostrea gigas contains glycogen, taurine, and amino acids, and has been assigned diverse health-promoting properties. This study investigated the anti-colitis effect of OE intake on fecal microbiota and its metabolites of acute experimental colitis mouse model induced by dextran sulfate sodium (DSS). C57BL/6J mice (male) were divided into three groups: (1) American Institute of Nutrition (AIN) 93G diet + DSS-untreated, (2) AIN93G diet + DSS-treated, and (3) 5% OE diet + DSS-treated. Mice were fed each diet for 21 days, and then administered 2.5% DSS solution to induce acute colitis for 7 days. In DSS-induced colitis mice, OE decreased body weight loss and increased disease activity index during the DSS-induced period. In addition, OE tended to decrease the colon length shortening and the relative spleen weight and alleviated colonic tissue damage. Moreover, OE improved fecal short-chain fatty acids compositions and altered the structure of fecal microbiota. These results provide insight into the health-promoting property of OE in alleviating DSS-induced acute colitis, providing a basis for the development and use of functional foods.

Janus kinase-targeting therapies in rheumatology: a mechanisms-based approach

The four Janus kinase (JAK) proteins and seven signal transducer and activator of transcription (STAT) transcription factors mediate intracellular signal transduction downstream of cytokine receptors, which are implicated in the pathology of autoimmune, allergic and inflammatory diseases. Development of targeted small-molecule therapies such as JAK inhibitors, which have varied selective inhibitory profiles, has enabled a paradigm shift in the treatment of diverse disorders. JAK inhibitors suppress intracellular signalling mediated by multiple cytokines involved in the pathological processes of rheumatoid arthritis and many other immune and inflammatory diseases, and therefore have the capacity to target multiple aspects of those diseases. In addition to rheumatoid arthritis, JAK inhibition has potential for treatment of autoimmune diseases including systemic lupus erythematosus, spondyloarthritis, inflammatory bowel disease and alopecia areata, in which stimulation of innate immunity activates adaptive immunity, leading to generation of autoreactive T cells and activation and differentiation of B cells. JAK inhibitors are also effective in the treatment of allergic disorders, such as atopic dermatitis, and can even be used for the COVID-19-related cytokine storm. Mechanism-based treatments targeting JAK-STAT pathways have the potential to provide positive outcomes by minimizing the use of glucocorticoids and/or non-specific immunosuppressants in the treatment of systemic immune-mediated inflammatory diseases.

An Update on the Pathogenic Role of Neutrophils in Systemic Juvenile Idiopathic Arthritis and Adult-Onset Still's Disease

Neutrophils are innate immune phagocytes that play a key role in immune defense against invading pathogens. The main offensive mechanisms of neutrophils are the phagocytosis of pathogens, release of granules, and production of cytokines. The formation of neutrophil extracellular traps (NETs) has been described as a novel defense mechanism in the literature. NETs are a network of fibers assembled from chromatin deoxyribonucleic acid, histones, and neutrophil granule proteins that have the ability to kill pathogens, while they can also cause toxic effects in hosts. Activated neutrophils with NET formation stimulate autoimmune responses related to a wide range of inflammatory autoimmune diseases by exposing autoantigens in susceptible individuals. The association between increased NET formation and autoimmunity was first reported in antineutrophil cytoplasmic antibody-related vasculitis, and the role of NETs in various diseases, including systemic lupus erythematosus, rheumatoid arthritis, and psoriasis, has since been elucidated in research. Herein, we discuss the mechanistic role of neutrophils, including NETs, in the pathogenesis of systemic juvenile idiopathic arthritis (SJIA) and adult-onset Still’s disease (AOSD), and provide their clinical values as biomarkers for monitoring and prognosis.

Interspecies variation in hominid gut microbiota controls host gene regulation

The gut microbiome exhibits extreme compositional variation between hominid hosts. However, it is unclear how this variation impacts host physiology across species and whether this effect can be mediated through microbial regulation of host gene expression in interacting epithelial cells. Here, we characterize the transcriptional response of human colonic epithelial cells in vitro to live microbial communities extracted from humans, chimpanzees, gorillas, and orangutans. We find that most host genes exhibit a conserved response, whereby they respond similarly to the four hominid microbiomes. However, hundreds of host genes exhibit a divergent response, whereby they respond only to microbiomes from specific host species. Such genes are associated with intestinal diseases in humans, including inflammatory bowel disease and Crohn’s disease. Last, we find that inflammation-associated microbial species regulate the expression of host genes previously associated with inflammatory bowel disease, suggesting health-related consequences for species-specific host-microbiome interactions across hominids.

Muehlbauer et al. investigate how variation between different hominid microbiomes drives host gene expression in colonic epithelial cell cultures. They find that host genes that respond only to microbiomes from a specific hominid species are linked to gastrointestinal diseases, suggesting implications for understanding how the microbiome can impact human health.

Meisoindigo attenuates dextran sulfate sodium-induced experimental colitis via its inhibition of TAK1 in macrophages

At present, inflammatory bowel disease (IBD) seriously threatens human health, and its treatment is a huge challenge for people. In our studies, we found that meisoindigo, a derivative of indirubin, significantly ameliorated dextran sulfate sodium (DSS)-induced experimental colitis in mice. Meisoindigo treatment markedly elevated the level of glutathione, while suppressed the activities of alkaline phosphatase and myeloperoxidase in colonic tissues. Moreover, the mRNA expression of vascular cell adhesion molecule 1, intercellular adhesion molecule 1, cyclooxygenase-2 which are important colitis-related molecules and the levels of the inflammatory cytokines interleukin (IL)-18, IL-1β, IL-6, tumor necrosis factor (TNF)-α and inducible nitric oxide synthase (iNOS) were suppressed dose-dependently following treatment with meisoindigo. Immunofluorescence results indicated that meisoindigo inhibited macrophage infiltration and nuclear factor (NF)-κB activation in colons from DSS-treated mice. Therefore, mouse RAW264.7 and human THP-1 cells were treated with lipopolysaccharide (LPS) alone or combined adenosine triphosphate to activate NF-κB pathway in vitro. It was shown that meisoindigo reduced the elevated levels of NO, IL-18, IL-1β and TNF-α after LPS treatment in both cells. In addition, meisoindigo showed inhibitory effects on NF-κB by using a luciferase reporter gene that depends on NF-κB. Through molecular docking, microscale thermophoresis and cellular thermal shift assay. It was further found that meisoindigo targeted transforming growth factor β activated kinase-1 (TAK1), which is an important regulator in the upstream of NF-κB pathway. In conclusion, our findings show that meisoindigo can alleviate IBD effectively at low doses, and negatively regulate proinflammatory responses by inhibiting the activation of TAK1, which provides new ideas for clinical anti-inflammatory therapy.

H19 Overexpression Improved Efficacy of Mesenchymal Stem Cells in Ulcerative Colitis by Modulating the miR-141/ICAM-1 and miR-139/CXCR4 Axes

Overexpression of C-X-C motif chemokine receptor 4 (CXCR4) and intercellular cell adhesion molecule-1 (ICAM-1) may promote homing of mesenchymal stem cells (MSC). In this study, we treated ulcerative colitis animals with MSC preconditioned with or without H19 and compared the therapeutic effect of MSC and MSC-H19. We evaluated the regulatory relationship of H19 vs. miR-141/miR-139 and miR-141/miR-139 vs. ICAM-1/CXCR4. We established an ulcerative colitis mouse model to assess the effect of MSC and MSC-H19. H19 was found to bind to miR-141 and miR-139. The activity of H19 was strongly decreased in cells c-transfected with miR-141/miR-139 and WT H19. ICAM-1 was confirmed to be targeted by miR-141 and CXCR4 was targeted by miR-139. The H19 expression showed a negative regulatory relationship with the miR-141 and miR-139 expression but a positive regulatory relationship with the ICAM-1 and CXCR4 expression. In summary, the overexpression of H19 in MSC downregulated miR-139 and miR-141, thus increasing the activity of their targets ICAM-1 and CXCR4, respectively, to exhibit therapeutic effects in ulcerative colitis.

Atopic Diseases Are Associated With Development of Inflammatory Bowel Diseases in Korea: A Nationwide Population-based Study

BACKGROUND & AIMS

The association between atopic diseases and inflammatory bowel diseases (IBD) is unclear. We conducted a nationwide population-based study in Korea to investigate the effect of atopic diseases on the development of IBD.

METHODS

A total of 9,923,521 participants, who received a medical check-up in 2009, were included and followed through 2017. The presence of any atopic diseases, including atopic dermatitis (AD), allergic rhinitis (AR), and asthma, was evaluated. Patients who developed IBD, including Crohn's disease (CD) and ulcerative colitis (UC), were identified using claims data from National Health Insurance; the association between atopic diseases and the risk of IBD was evaluated using Cox proportional hazard models, and presented as adjusted hazard ratios (aHRs) with 95% CIs.

RESULTS

During a mean follow-up period of 7.3 years, 1419 patients (0.014%) developed CD and 5897 patients (0.059%) developed UC. The incidences of CD (per 100,000 person-years) were 3.756, 2.248, and 2.346 in patients with AD, AR, or asthma, respectively. The incidences of UC were 11.952, 9.818, and 9.358 in patients with AD, AR, or asthma, respectively. Multivariable analysis revealed that the aHRs for incident CD in patients with AD, AR, or asthma were 2.02, 1.33, and 1.60 (95% CIs, 1.118-3.663, 1.149-1.529, and 1.193-2.136, respectively) compared with controls. The risks of incident UC in patients with AD, AR, or asthma were 1.51, 1.32, and 1.29 (95% CIs, 1.082-2.104, 1.229-1.410, and 1.115-1.491, respectively) compared with controls. Moreover, an increase in the number of atopic diseases gradually increased the risk for CD and UC; for 1 or 2 or more atopic diseases, the aHRs for CD were 1.35 and 1.65 (95% CIs, 1.171-1.560 and 1.146-2.376), and the aHRs for UC were 1.30 and 1.49 (95% CIs, 1.211-1.392 and 1.249-1.774), respectively.

CONCLUSIONS

Based on a nationwide population-based study in Korea, patients with any atopic disease, including AD, AR, or asthma, have an increased risk for CD and UC. The risk for IBD increases with the increase in the number of atopic diseases.

Investigating the shared genetic architecture between multiple sclerosis and inflammatory bowel diseases

An epidemiological association between multiple sclerosis (MS) and inflammatory bowel disease (IBD) is well established, but whether this reflects a shared genetic aetiology, and whether consistent genetic relationships exist between MS and the two predominant IBD subtypes, ulcerative colitis (UC) and Crohn’s disease (CD), remains unclear. Here, we use large-scale genome-wide association study summary data to investigate the shared genetic architecture between MS and IBD overall and UC and CD independently. We find a significantly greater genetic correlation between MS and UC than between MS and CD, and identify three SNPs shared between MS and IBD (rs13428812), UC (rs116555563) and CD (rs13428812, rs9977672) in cross-trait meta-analyses. We find suggestive evidence for a causal effect of MS on UC and IBD using Mendelian randomization, but no or weak and inconsistent evidence for a causal effect of IBD or UC on MS. We observe largely consistent patterns of tissue-specific heritability enrichment for MS and IBDs in lung, spleen, whole blood and small intestine, and identify cell-type-specific enrichment for MS and IBDs in CD4⁺ T cells in lung and CD8⁺ cytotoxic T cells in lung and spleen. Our study sheds light on the biological basis of comorbidity between MS and IBD.

An epidemiological association between multiple sclerosis (MS) and inflammatory bowel disease (IBD) is well-established, but a genetic link is unclear. Here, the authors investigate the shared genetic architecture between MS and IBD to shed light on the biological basis of comorbidity.

Canagliflozin, an SGLT-2 inhibitor, ameliorates acetic acid-induced colitis in rats through targeting glucose metabolism and inhibiting NOX2

BACKGROUND

Inflammatory bowel disease is defined as chronic noninfectious inflammation of the gastrointestinal tract, including ulcerative colitis and Crohn's disease. Its incidence and predominance have increased globally, with no effective agents for preventing its recurrence or treatment until now.

AIM

The current study aimed to investigate the possible role of canagliflozin (CANA), a sodium-glucose co-transporter-2 inhibitor (SGLT-2), to prevent and treat acetic acid (AA)-induced colitis in a rat model.

METHODS

Colitis was induced in male Wistar rats by intrarectal instillation of 1 ml of 4% (v/v) AA. Rats were treated orally with either CANA (30 mg/kg/day, p.o.) for 10 days before or after colitis induction or sulfasalazine (360 mg/kg/day, p.o.) for 10 days before colitis induction.

RESULTS

AA resulted in a significant increase in disease activity index, colonic weight over length ratio, colon macroscopic damage score, and histological signs of colitis. All of these effects were significantly decreased by CANA administration. Additionally, CANA markedly inhibited AA-induced oxidative stress and inflammatory responses by significantly reducing the up-regulated levels in malondialdehyde, total nitrite, NF-κB, interleukin-1β, and TNF-α, and significantly increasing the down-regulated levels in reduced glutathione, superoxide dismutase, and interleukin-10. CANA significantly inhibited caspase-3 level while rescued survivin expression in colons. Finally, CANA reduced the elevated levels of pyruvic acid and G6PDH activity, as well as the levels of p22phox and NOX2 in the AA-induced colitis.

CONCLUSION

Our findings provide novel evidence that CANA has protective and therapeutic effects against AA-induced colitis by the impact of its antioxidant, anti-inflammatory, and anti-apoptotic effects.

Kaempferol Alleviates Murine Experimental Colitis by Restoring Gut Microbiota and Inhibiting the LPS-TLR4-NF-κB Axis

Intestinal microbiota dysbiosis is an established characteristic of ulcerative colitis (UC). Regulating the gut microbiota is an attractive alternative UC treatment strategy, considering the potential adverse effects of synthetic drugs used to treat UC. Kaempferol (Kae) is an anti-inflammatory and antioxidant flavonoid derived from a variety of medicinal plants. In this study, we determined the efficacy and mechanism of action of Kae as an anti-UC agent in dextran sulfate sodium (DSS)-induced colitis mice. DSS challenge in a mouse model of UC led to weight loss, diarrhea accompanied by mucous and blood, histological abnormalities, and shortening of the colon, all of which were significantly alleviated by pretreatment with Kae. In addition, intestinal permeability was shown to improve using fluorescein isothiocyanate (FITC)-dextran administration. DSS-induced destruction of the intestinal barrier was also significantly prevented by Kae administration via increases in the levels of ZO-1, occludin, and claudin-1. Furthermore, Kae pretreatment decreased the levels of IL-1β, IL-6, and TNF-α and downregulated transcription of an array of inflammatory signaling molecules, while it increased IL-10 mRNA expression. Notably, Kae reshaped the intestinal microbiome by elevating the Firmicutes to Bacteroidetes ratio; increasing the linear discriminant analysis scores of beneficial bacteria, such as Prevotellaceae and Ruminococcaceae; and reducing the richness of Proteobacteria in DSS-challenged mice. There was also an evident shift in the profile of fecal metabolites in the Kae treatment group. Serum LPS levels and downstream TLR4-NF-κB signaling were downregulated by Kae supplementation. Moreover, fecal microbiota transplantation from Kae-treated mice to the DSS-induced mice confirmed the effects of Kae on modulating the gut microbiota to alleviate UC. Therefore, Kae may exert protective effects against colitis mice through regulating the gut microbiota and TLR4-related signaling pathways. This study demonstrates the anti-UC effects of Kae and its potential therapeutic mechanisms, and offers novel insights into the prevention of inflammatory diseases using natural products.

Flaxseed oligosaccharides alleviate DSS-induced colitis through modulation of gut microbiota and repair of the intestinal barrier in mice

Intestinal epithelial barrier dysfunction with dysbiosis of gut microbiota contributes to the occurrence and acceleration of colitis. This study aimed to evaluate the effect of flaxseed oligosaccharides (FOSs) on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) mice and to elucidate the underlying mechanisms. UC was induced in mice by administering 2% DSS in drinking water for 8 days. Then, FOS (50 mg kg-1 d-1, 100 mg kg-1 d-1 and 200 mg kg-1 d-1) was administered by gavage for 14 days. The results showed that FOS treatment (200 mg kg-1 d-1) significantly ameliorated colitis by decreasing disease activity index (DAI), increasing colon length and improving colonic histology. FOS treatment (200 mg kg-1 d-1) down-regulated the critical markers of oxidative stresses, including malondialdehyde (MDA) and myeloperoxidase (MPO). Furthermore, FOS (200 mg kg-1 d-1) significantly suppressed the levels of pro-inflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-6 and interleukin (IL)-1β but increased that of anti-inflammatory cytokine interleukin (IL)-10. The 16S rDNA gene high-throughput sequencing results indicated that FOS treatment increased the gut microbial diversity and inhibited the proliferation of inflammation-related bacteria such as unidentified_Clostridiales. An increase in total short-chain fatty acids (SCFAs), propionic acid and butyric acid, was also observed by FOS supplementation. FOS (200 mg kg-1d-1) also protected the intestinal barrier by increasing the protein levels of Claudin1 and Occludin. In conclusion, FOS attenuated DSS-induced colitis by modulating the gut microbiota and repairing the intestinal barrier.

Antioxidant Therapy in Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD) are a group of chronic, incurable diseases of the digestive tract, the etiology of which remains unclear to this day. IBD result in significant repercussions on the quality of patients’ life. There is a continuous increase in the incidence and prevalence of IBD worldwide, and it is becoming a significant public health burden. Pharmaceuticals commonly used in IBD management, for example, mesalamine, sulfasalazine, corticosteroids, and others, expose patients to diverse, potentially detrimental side effects and frequently do not provide sufficient disease control. The chronic inflammation underlies the etiology of IBD and closely associates with oxidative/nitrosative stress and a vast generation of reactive oxygen/nitrogen species. Relative to this, several substances with antioxidant and anti-inflammatory properties are now intensively researched as possible adjunctive or independent treatment options in IBD. Representatives of several different groups, including natural and chemical compounds will be characterized in this dissertation.

Effect of Cynara cardunculus L. var. altilis (DC) in Inflammatory Bowel Disease

Background: Cynara cardunculus L. var. altilis (DC) is a plant generally associated as an ingredient in the Mediterranean diet. The polyphenols present in this plant provide pharmacological and nutritional properties. C. cardunculus L. has been used throughout animal studies, which demonstrated an anti-inflammatory effect. Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract. Since there is not a known cure, the research of new possible pharmacological approaches is essential. This study aims to evaluate the effect of an aqueous extract of C. cardunculus L. dry leaves in a 2,4,6-Trinitrobenzenesulfonic acid (TNBS)-induced colitis model. Methods: CD-1 mice with TNBS-induced colitis received an intraperitoneal (IP) administration of C. cardunculus L. once per day for 4 days. Results: The C. cardunculus L. demonstrated a beneficial effect in this experimental model of IBD with anti-inflammatory action through the reduction of tumor necrosis factor (TNF)-α levels. It also demonstrated a beneficial influence on the extra-intestinal manifestations related to IBD, with the absence of significant side effects of its use. Conclusions: The extract of C. cardunculus L. dry leaves can become an interesting tool for new possible pharmacological approaches in the management of IBD.

Hyptis suaveolens (L.) Poit protects colon from TNBS-induced inflammation via immunomodulatory, antioxidant and anti-proliferative mechanisms

ETHNOPHARMACOLOGICAL RELEVANCE

In folk medicine Hyptis suaveolens (Lamiaceae) has been reported to relieve respiratory and gastrointestinal infections, indigestion, cold, pain, fever, cramps, skin diseases, gastric ulcer and inflammatory disorders. This study investigated the effects and the mechanisms of action of Hyptis suaveolens (L.) Poit (Lamiaceae) ethanol extract (Hs-EtOH) and hexane phase (Hs-HexF) against intestinal inflammation.

MATERIAL AND METHODS

Acute and relapse TNBS-induced ulcerative colitis protocols were used to evaluate intestinal anti-inflammatory activity. Damage evaluations, biochemical, histological and immunostaining parameters were determined.

RESULTS

Both extracts decreased macroscopic colonic inflammation and the area of lesion induced by TNBS. Nevertheless, only Hs-HexF was able to reduce colonic wall thickness, edema and diffuse inflammatory cell infiltration and to prevent GSH depletion in the acute model of ulcerative colitis. In the chronic phase with relapse of colonic ulceration, yet again only Hs-HexF significantly attenuated inflammatory parameters and presented a decrease in nitrite/nitrate, MDA, MPO, IL-1-β and TNF-α and increased levels of SOD, CAT, GSH and IL-10. Hs-HexF also significantly reduced positive cells immunostained for PCNA.

CONCLUSION

The data indicate intestinal anti-inflammatory activity for H. suaveolens, due to the participation of the antioxidant system, decreased neutrophil infiltration and cytokine modulation, as well as, owing to regulation of cell proliferation.

Long-term Prognosis of Localized Lymphoid Hyperplasia of the Rectum

Background/Aims

Although localized lymphoid hyperplasia (LLH) of the rectum is occasionally observed, its clinical implications are unclear. This study aimed to investigate the clinical course and significance of LLH of the rectum.

Methods

We identified 65 patients diagnosed with LLH of the rectum using a histopathologic examination and who received follow-up endoscopies between January 2009 and June 2015. Patients with a history of inflammatory bowel disease, lymphoma, familial adenomatous polyposis, or uncontrolled malignancy and patients who underwent scar biopsy after endoscopic resection or surgery were excluded. Endoscopic findings and clinical courses were analyzed.

Results

During the median follow-up of 31 months (interquartile range, 19 to 40 months), 81.5% (53/65) of LLHs of the rectum were resolved. Clinically significant diseases, including ulcerative colitis (UC, n=5) and mucosa-associated lymphoid tissue (MALT) lymphoma (n=1), were diagnosed in 9.2% of patients (6/65). The other six patients showed no significant changes in the lesion (n=3) or a waxing and waning appearance (n=3). According to endoscopic findings, all of the 47 polypoid types showed resolution or waxing and waning patterns. Five of the 11 nodular types (45.5%) developed into UC. One of the seven submucosal tumor (SMT)-like types (14.3%) developed into MALT lymphoma.

Conclusions

LLH of the rectum with persistent symptoms or the endoscopic appearance of the nodular or SMT-like type may lead to clinically significant disease. Risk stratification according to endoscopic findings and careful surveillance are required for these lesions.

The Role of Organoids as a Novel Platform for Modeling of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic relapsing-remitting immune-mediated disorder affecting the gut. It is common in Westernized regions and is increasing in incidence in developing countries. At a molecular level, intrinsic deficiencies in epithelial integrity, mucosal barrier function, and mechanisms of immune response and resolution contribute to the development of IBD. Traditionally two platforms have been utilized for disease modeling of IBD; in-vitro monolayer cell culture and in-vivo animal models. Both models have limitations, including cost, lack of representative cell types, lack of complexity of cellular interactions in a living organism, and xenogeneity. Organoids, three-dimensional cellular structures which recapitulate the basic architecture and functional processes of the organ of origin, hold potential as a third platform with which to investigate the pathogenesis and molecular defects which give rise to IBD. Organoids retain the genetic and transcriptomic profile of the tissue of origin over time and unlike monolayer cell culture can be induced to differentiate into most adult intestinal cell types. They may be used to model intestinal host-microbe interactions occurring at the mucosal barrier, are amenable to genetic manipulation and can be co-cultured with other cell lines of interest. Bioengineering approaches may be applied to render a more faithful representation of the intestinal epithelial niche. In this review, we outline the concept of intestinal organoids, discuss the advantages and disadvantages of the platform comparative to alternative models, and describe the translational applications of organoids in IBD.

Therapeutic Potential of Triptolide as an Anti-Inflammatory Agent in Dextran Sulfate Sodium-Induced Murine Experimental Colitis

Inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn’s disease (CD), is a group of chronic and incurable inflammatory diseases involving the gastrointestinal tract. In this study, we investigated the anti-inflammatory effects of triptolide in a dextran sulfate sodium (DSS)-induced mouse colitis model and LPS-activated macrophages and explored the specific molecular mechanism(s). In mice, triptolide treatment showed significant relief and protection against colitis, and it markedly reduced the inflammatory responses of human monocytes and mouse macrophages. Pharmacological analysis and weighted gene co-expression network analysis (WGCNA) suggested that PDE4B may be an important potential targeting molecule for IBD. Exploration of the specific mechanism of action indicated that triptolide reduced the production of ROS, inhibited macrophage infiltration and M1-type polarization by activating the NRF2/HO-1 signaling pathway, and inhibited the PDE4B/AKT/NF-κB signaling cascade, which may help weaken the intestinal inflammatory response. Our findings laid a theoretical foundation for triptolide as a treatment for IBD and revealed PDE4B as a target molecule, thus providing new ideas for the treatment of IBD.

Standardized Fraction of Turbinaria ornata Alleviates Dextran Sulfate Sodium-Induced Chronic Colitis in C57BL/6 Mice via Upregulation of FOXP3+ Regulatory T Cells

Turbinaria ornata is a tropical brown algae (seaweed) known to have anti-inflammatory properties. In this study, we analyzed T. ornata extract (TOE) using liquid chromatography quadrupole time of flight mass spectrometry (LC-QTOF-MS) and nuclear magnetic resonance (NMR) and evaluated the in vivo efficacy of TOE against dextran sulfate sodium-induced chronic colitis in C57BL/6 mice. The bioactive fraction of TOE was administered orally daily for 6 weeks to mice under different treatments normal, colitis, and colitis + conventional drug (5-aminosalicylic acid, 5-ASA). Regarding clinical manifestation, the disease activity index and colon length of the colitis + TOE group were significantly reduced compared to those of the colitis group. The results of myeloperoxidase activity and histopathological examination showed similar results. Western blot analysis of colon tissues revealed that cyclooxygenase-2, tumor necrosis factor alpha (TNF-α), and phosphorylated signal transducer and activator of transcription-3 (p-STAT3) were significantly decreased in the colitis + 5-ASA group, whereas forkhead box P3 (FOXP3) was increased. qPCR results showed changes in T cell subsets; the administration of TOE upregulated regulatory T cell (Treg) expression, although T helper 17 cell (Th17) expression did not change significantly. Interestingly, the colitis + TOE group showed high levels of both Th1 and Th2 transcription factors, but the secreted cytokine interferon (IFN)-γ and interleukin (IL)-4 remained unchanged and somewhat reduced. Additionally, TNF-α gene expression was significantly reduced in the colitis + TOE group. IL-6 mRNA levels were also decreased, although not significantly. Four compounds were structurally elucidated using 1D- and 2D-NMR spectroscopy, and five compounds were fully identified or tentatively characterized using LC-QTOF-MS. In conclusion, TOE could alleviate chronic colitis via upregulation of Foxp3+ Treg cells and production of the anti-inflammatory cytokine IL-10, which directly inhibits macrophages and pro-inflammatory cytokine synthesis, leading to reduced colitis.

The Synthetic Myeloperoxidase Inhibitor AZD3241 Ameliorates Dextran Sodium Sulfate Stimulated Experimental Colitis

Chronic inflammatory bowel disease (IBD) is a condition with multifactorial pathophysiology. To date, there is no permanent cure and the disease is primarily managed by immunosuppressive drugs; long-term use promotes serious side effects including increased risk malignancies. The current study aimed to target neutrophil-myeloperoxidase, a key contributor to the pathogenesis of IBD, through the use of AZD3241that inhibits extracellular myeloperoxidase. Experimental colitis was induced in C57BL/6 male mice by 2% dextran sodium sulfate in drinking water ad libitum over 9 days. Mice received either normal drinking water and peanut butter (control), 2% DSS in drinking water and peanut butter or 2% DSS in drinking water and AZD3241 (30 mg/kg) dispersed in peanut butter daily for 9 days. Administered AZD3241 attenuated body weight loss (10% p<0.05) and improved clinical score (9 fold p<0.05; a score comprising the time-dependent assessment of stool consistency and extent of rectal bleeding), loss of colonic crypts (p<0.001), preserved surface epithelium (p<0.001) and enhanced expression of the transcription factor Nrf-2 (regulator of antioxidants) and enhanced expression of the downstream antioxidant response element haeoxygenase-1 (HO-1) in the colon tissue. Also, the concentration of fecal hemoglobin and the myeloperoxidase specific oxidative damage biomarker 3-chlorotyrosine in the colon were significantly decreased in the presence of AZD3241. This latter result was consistent with AZD3241 inhibiting MPO activity in vitro. Overall, AZD3241 ameliorated the course and severity of experimental colitis through ameliorating MPO derived tissue damage and could be considered a potential therapeutic option, subject to further validation in chronic IBD models.

HSP70, a Novel Regulatory Molecule in B Cell-Mediated Suppression of Autoimmune Diseases

B cells have recently emerged as playing regulatory role in autoimmune diseases. We have previously demonstrated that human peripheral blood CD19⁺CD24^hiCD27⁺ B cells have regulatory function both in healthy donors and in patients with autoimmune disease. However, the mechanism of this regulation is still not fully understood. In this study, microarrays were utilized to compare gene expression of CD19⁺CD24^hiCD27⁺ B cells (regulatory B cells, Bregs) with CD19⁺CD24^loCD27^- B cells (non-Bregs) in human peripheral blood. We found that heat shock protein 70 (HSP70) expression was significantly upregulated in Bregs. In vitro studies explored that HSP70 inhibition impaired the regulatory function of peripheral blood Bregs. In mouse models of autoimmune disease, using HSP70-deficient mice or HSP70 inhibitors, Bregs suppressed effector cells and rescued disease-associated phenotypes that were dependent on HSP70. Mechanistically, Bregs secreted HSP70, directly suppressing effector cells, such as T effect cells. These findings reveal that HSP70 is a novel factor that modulates Breg function and suggest that enhancing Breg-mediated production of HSP70 could be a viable therapy for autoimmune disease.

p-Cymene and Rosmarinic Acid Ameliorate TNBS-Induced Intestinal Inflammation Upkeeping ZO-1 and MUC-2: Role of Antioxidant System and Immunomodulation

p-Cymene (p-C) and rosmarinic acid (RA) are secondary metabolites that are present in medicinal herbs and Mediterranean spices that have promising anti-inflammatory properties. This study aimed to evaluate their intestinal anti-inflammatory activity in the trinitrobenzene sulphonic acid (TNBS)-induced colitis model in rats. p-C and RA (25-200 mg/kg) oral administration reduced the macroscopic lesion score, ulcerative area, intestinal weight/length ratio, and diarrheal index in TNBS-treated animals. Both compounds (200 mg/kg) decreased malondialdehyde (MDA) and myeloperoxidase (MPO), restored glutathione (GSH) levels, and enhanced fluorescence intensity of superoxide dismutase (SOD). They also decreased interleukin (IL)-1β and tumor necrosis factor (TNF)-α, and maintained IL-10 basal levels. Furthermore, they modulated T cell populations (cluster of differentiation (CD)4+, CD8+, or CD3+CD4+CD25+) analyzed from the spleen, mesenteric lymph nodes, and colon samples, and also decreased cyclooxigenase 2 (COX-2), interferon (IFN)-γ, inducible nitric oxide synthase (iNOS), and nuclear transcription factor kappa B subunit p65 (NFκB-p65) mRNA transcription, but only p-C interfered in the suppressor of cytokine signaling 3 (SOCS3) expression in inflamed colons. An increase in gene expression and positive cells immunostained for mucin type 2 (MUC-2) and zonula occludens 1 (ZO-1) was observed. Altogether, these results indicate intestinal anti-inflammatory activity of p-C and RA involving the cytoprotection of the intestinal barrier, maintaining the mucus layer, and preserving communicating junctions, as well as through modulation of the antioxidant and immunomodulatory systems.

Mortality and Hospitalizations in Mexican Patients with Inflammatory Bowel Disease: Results from a Nationwide Health Registry

BACKGROUND

Incidence of inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease (CD), is increasing worldwide; nevertheless, it is still unknown if this is the case in Mexico. Thus, the aim of this study was to analyze the distribution and trends of hospital discharges (HD) (for the period between 2004 and 2015) and deaths (for the period between 2004 and 2013) reported for UC and CD in Mexico.

METHODS

Quantitative cross-sectional study was performed. Secondary data sources analysis was performed through Dynamic Cubes of the General Direction of Health Information; variables were categorized by diagnosis, age, sex, and state. The Mann-Whitney U test was used to analyze the differences between the first and last years that were studied. Statistical analysis was performed in SPSS v.24.

RESULTS

The number of HD increased by 98.9% between 2004 and 2015 (IBD: p=0.033, CD: p=0.009, UC: p=0.051); it was more frequent, for both sexes and diagnoses, between 15 and 44 years, with a second peak for men with UC (between 45 and 64 years). Deaths increased by 96.2% from 2004 to 2011 (IBD: p=0.056, CD: p=0.064, UC: p=0.04). UC is three times more frequent than CD. Mexico City has the highest number of HD (4,179; 22.7%) while the state of Veracruz has the highest number of deaths (273; 38.2%).

CONCLUSIONS

HD for IBD in Mexico is increasing significantly; the number of deaths increased until 2011, but from then on, they are apparently decreasing. IBD affects Mexican people without any gender predominance, often affecting patients between 15 and 44 years of age. UC is three times more frequent than CD.

Intervention with the crude polysaccharides of Physalis pubescens L. mitigates colitis by preventing oxidative damage, aberrant immune responses, and dysbacteriosis

In this study, a colitis mouse model induced by dextran sulfate sodium (DSS) was used to investigate the mechanisms of action of an extract of crude polysaccharides (POL) from Physalis pubescens L. as a dietary intervention for colitis. Our results showed that the administration of POL prior to DSS-induced colitis protected the colon mucosal layer; maintained intestinal barrier integrity; alleviated oxidative damage; and lowered neutrophil infiltration by downregulating intercellular cell adhesion molecule-1 and monocyte chemoattractant protein-1 expression. More importantly, POL pretreatment reduced the expression of the proinflammatory factors tumor necrosis factor-α, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), thereby modulating the nuclear factor-κB/iNOS-COX-2 signal transduction pathway. In addition, POL reversed DSS-induced gut dysbiosis, accompanied by reducing the relative abundance of Helicobacter, Mucispirillum, and Erysipelatoclostridium. In conclusion, POL ameliorated DSS-induced intestinal injury in mice, indicating that POL could be a useful dietary nutrient to protect against colitis. PRACTICAL APPLICATION: Physalis pubescens L. is an edible fruit. The results of this study show that the intervention with Physalis pubescens L. crude polysaccharides may help prevent ulcerative colitis.

Methane Alleviates Inflammation and Apoptosis of Dextran Sulfate Sodium-Induced Inflammatory Bowel Diseases by Inhibiting Toll-Like Receptor 4 (TLR4)/Myeloid Differentiation Factor 88 (MyD88)/Nuclear Translocation of Nuclear Factor-κB (NF-κB) and Endoplasmic Reticulum Stress Pathways in Mice

Background

Inflammatory bowel diseases (IBDs) are chronic idiopathic diseases with increased occurrence and recurrence rates. The aim of this study was to explore whether methane-rich saline (MRS) would be beneficial to IBD.

Material/Methods

Dextran sulfate sodium (DSS) was utilized to establish an IBD model. Male C57BL/6J mice were randomly grouped as follows: the control group, the DSS+NS group, the DSS+5-ASA group, the DSS+MRS (1) and DSS+MRS (10) groups. Seven days after model induction, blood and colon tissues were collected to assess the treatment effects.

Results

The DSS+MRS (10) group showed obviously reduced weight loss, disease activity index, and spleen index. The isolated colon samples had a notably longer length, less thickness and weight, and better macroscopic score with MRS treatment compared with the DSS+NS group. Additionally, assessment of morphological impairment revealed a milder and lower microscopic score in the DSS+MRS (10) group, consistent with the myeloperoxidase (MPO) results. The inflammation-related molecules levels were dramatically reduced by MRS. MRS also significantly reduced oxidative stress related proteins. In addition, apoptotic cells were visually decreased in the DSS+MRS (10) group, in which the pro-apoptotic molecules Bax and cleaved caspase-3 were reduced, whereas the level of Bcl-2 was increased. Furthermore, MRS markedly decreased the TLR4, MyD88, p-NF-κB p65, p-IKKαβ, and p-IκBα, and increased IL-10, p-JAK1, and p-STAT3 expression levels. Proteins involved in endoplasmic reticulum stress (ERS) were also notably reduced under MRS treatment.

Conclusions

MRS exerts protective effects on DSS-induced IBD via inhibiting inflammatory reaction, promoting anti-inflammatory capacity, suppressing oxidative stress, and ameliorating apoptosis.

High-Resolution Regulatory Maps Connect Vascular Risk Variants to Disease-Related Pathways

Supplemental Digital Content is available in the text.

Genetic variant landscape of coronary artery disease is dominated by noncoding variants among which many occur within putative enhancers regulating the expression levels of relevant genes. It is crucial to assign the genetic variants to their correct genes both to gain insights into perturbed functions and better assess the risk of disease.