Further research on the clinical relevance of the ulcerative colitis colonoscopic index of severity for predicting 5-year relapse

Escin Ia ameliorates DSS-induced chronic colitis in mice by inhibiting inflammation and oxidative stress via the LOXL2/MMP-9 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Aesculus wilsonii Rehd.'s dried mature seeds are the source of escin, a significant triterpenoid saponin. Aesculus wilsonii Rehd was first mentioned in the Compendium of Materia Medica, according to the Chinese Pharmacopoeia. It possesses the effectiveness of anti-inflammatory as well as treating gastrointestinal disorders. Escin Ia is the primary active component of escin, exhibiting significant antioxidant and anti-inflammatory properties. An increasing number of studies have demonstrated that escin exhibits a broad spectrum of pharmacological activities beneficial for the protection against gastrointestinal diseases.

AIM OF THE STUDY

Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) that can be managed through pharmacological treatment; however, it features a high recurrence rate as well as propensity for complications. Therefore, reducing the rate of recurrence and improving the recurrence symptoms should be the primary focus of clinical prevention and treatment. Therefore, this research aims to study the effects of escin Ia on inflammation as well as oxidative stress in mice with chronic UC and to explain the molecular mechanisms underlying its potential to improve recurrent symptoms in UC mice.

MATERIALS AND METHODS

A mouse model of colitis produced via dextran sodium sulfate (DSS) was developed for in vivo studies. A model of inflammation was created in vitro using caco-2 cells that were generated by lipopolysaccharide (LPS). Through the observation of colitis symptoms and histological morphology in mice, the protective effect of escin Ia against colitis was ascertained. The enzyme-linked immunosorbent assay (ELISA) and biochemical kits were then harnessed to measure the levels of oxidative stress markers as well as inflammatory factors. Additionally, to identify the possible target and molecular mechanism of escin Ia, qRT-PCR and western blotting, immunofluorescence, molecular docking, and molecular dynamics modeling were employed.

RESULTS

We demonstrated that escin Ia remarkably improved the colitis symptoms as well as histological features of DSS-treated mice, lowered the levels of proinflammatory cytokines as well as oxidative stress biomarkers, and subsequently restored the permeability of the intestinal mucosa. Additionally, high expression of LOXL2 significantly reduced the protective effects of escin Ia in both inflamed mice and Caco-2 cells. Furthermore, escin Ia exhibited a strong binding affinity and notable stability with LOXL2.

CONCLUSION

Escin Ia inhibits inflammation and oxidative stress through the LOXL2/MMP-9 pathway, thereby restoring intestinal mucosal barrier function. Improved recurrent symptoms in mice with enteritis.

The protective effect of naringenin on ulcerative colitis in mice through increasing Nrf2 pathway activity

Ulcerative colitis (UC) is a chronic inflammatory disease with an increasing prevalence worldwide. Naringenin (NAR) has been proven effective in preventing UC, but its mechanism has not been fully elucidated. In this study, network pharmacology and bioinformatics methods are used to screen the genes associated with NAR and UC. A mouse model of dextran sulfate sodium (DSS)-induced UC is established. After treatment with NAR, the disease activity index (DAI) is scored, and colonic histopathology is observed via hematoxylin-eosin (HE) staining. The expressions of the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway and inflammation-related factors in the colons of UC mice are examined via western blot analysis and immunohistochemistry (IHC). The results of the animal experiments reveal that the model group of UC mice present the most severe weight loss and the highest DAI scores. After the administration of NAR, weight loss is alleviated, and DAI scores are reduced ( P < 0.05). NAR improves pathological manifestations in the mouse colon, such as reducing inflammatory cell infiltration and restoring goblet cell loss ( P < 0.05). NAR significantly increases the protein expression levels of Nrf2, heme oxygenase 1 (HO-1), and NAD(P)H dehydrogenase [quinone] 1 (NQO1) in the colon ( P < 0.05) but decreases the protein expression levels of nuclear factor kappa-B (NF-κB), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) ( P < 0.05), thus alleviating the inflammatory response in UC model mice.

Astragalus mongholicus Bunge extract improves ulcerative colitis by promoting PLCB2 to inhibit colonic epithelial cell pyroptosis

ETHNOPHARMACOLOGICAL RELEVANCE

Astragalus mongholicus Bunge (AM) and its active ingredients are mainly used for anti-inflammatory, antiviral, antioxidant, immune regulation, cardiovascular and nervous system protection, anti-cancer, anti-tumor and so on.

AIM OF THE STUDY

To explore the Astragalus mongholicus Bunge extract pharmacological mechanisms and biology processes which improves ulcerative colitis (UC).

MATERIALS AND METHODS

Dextran sulfate sodium (DSS)-induced UC models in C57BL/6 mice were established, and the mice were treated with Astragalus mongholicus Bunge extract or salazosulfapyridine (SASP). DSS-induced mice- and human-derived colonic epithelial cell lines were used to reveal the inflammatory environment of UC. After treatment with Astragalus mongholicus Bunge extract, the expression of phospholipase C-β 2 (PLCB2) in the cells was detected by quantitative real-time PCR (qRT-PCR), and cell proliferative activity was detected by cell counting kit 8 (CCK-8) assay. Finally, the levels of pyroptosis-related inflammatory factors in cell culture supernatants was detected by ELISA.

RESULTS

Treatment of UC mice with Astragalus mongholicus Bunge extract do significantly improved DAI scores and histopathological damage scores, and decreased the levels of Eotaxin, GCSF, KC, MCP-1, TNF-α, and IL-6. Besides, Astragalus mongholicus Bunge extract inhibited the expression of nucleotide-binding oligomerization segment-like receptor family 3 (NLRP3), cleaved Caspase-1, and GSDMD-N in the colonic tissues, and reduced the levels of inflammation-related factors IL-1β and IL-18 in serum and tissues. In vitro, Astragalus mongholicus Bunge extract partially reversed the DSS-induced reduction of PLCB2 expression in CP-M030 and NCM460, promoted cell proliferative activity, and reduced the levels of IL-1β and IL-18.

CONCLUSIONS

In DDS-induced UC mice, Astragalus mongholicus Bunge extract improves ulcerative colitis by inhibiting colonic epithelial cell pyroptosis through PLCB2 promotion.

Deep mucosal healing in ulcerative colitis: how deep is better?

Ulcerative colitis (UC), characterized by its recurrent nature, imposes a significant disease burden and compromises the quality of life. Emerging evidence suggests that achieving clinical remission is not sufficient for long-term remission. In pursuit of a favorable prognosis, mucosal healing (MH) has been defined as the target of therapies in UC. This paradigm shift has given rise to the formulation of diverse endoscopic and histological scoring systems, providing distinct definitions for MH. Endoscopic remission (ER) has been widely employed in clinical practice, but it is susceptible to subjective factors related to endoscopists. And there's growing evidence that histological remission (HR) might be associated with a lower risk of disease flares, but the incorporation of HR as a routine therapeutic endpoint remains a debate. The integration of advanced technology has further enriched the definition of deep MH. Up to now, a universal standardized definition for deep MH in clinical practice is currently lacking. This review will focus on the definition of deep MH, from different dimensions, and analyze strengths and limitations, respectively. Subsequent multiple large-scale trials are needed to validate the concept of deep MH, offering valuable insights into potential benefits for UC patients.

Fecal calprotectin and endoscopic scores: The cornerstones in clinical practice for evaluating mucosal healing in inflammatory bowel disease

Managing inflammatory bowel disease (IBD) is becoming increasingly complex and personalized, considering the advent of new advanced therapies with distinct mechanisms of action. Achieving mucosal healing (MH) is a pivotal therapeutic goal in IBD management and can prevent IBD progression and reduce flares, hospitalization, surgery, intestinal damage, and colorectal cancer. Employing proactive disease and therapy assessment is essential to achieve better control of intestinal inflammation, even if subclinical, to alter the natural course of IBD. Periodic monitoring of fecal calprotectin (FC) levels and interval endoscopic evaluations are cornerstones for evaluating response/remission to advanced therapies targeting IBD, assessing MH, and detecting subclinical recurrence. Here, we comment on the article by Ishida et al Moreover, this editorial aimed to review the role of FC and endoscopic scores in predicting MH in patients with IBD. Furthermore, we intend to present some evidence on the role of these markers in future targets, such as histological and transmural healing. Additional prospective multicenter studies with a stricter MH criterion, standardized endoscopic and histopathological analyses, and virtual chromoscopy, potentially including artificial intelligence and other biomarkers, are desired.

New insights into the interactions between the gut microbiota and the inflammatory response to ulcerative colitis in a mouse model of dextran sodium sulfate and possible mechanisms of action for treatment with PE&AFWE

BACKGROUND

Inflammatory bowel disease (IBD), comprising Crohn's disease (CD) and ulcerative colitis (UC), is a heterogeneous state of chronic intestinal inflammation. Intestinal innate immunity, including innate immune cells, defends against pathogens and excessive entry of gut microbiota, while preserving immune tolerance to resident intestinal microbiota, and may be characterized by its capacity to produce a rapid and nonspecific reaction. The association between microbiota dysbiosis and the pathogenesis of IBD is complex and dynamic. When the intestinal ecosystem is in dysbiosis, the reduced abundance and diversity of intestinal gut microbiota make the host more vulnerable to the attack of exogenous and endogenous pathogenic gut microbiota. The aim of our study was to comprehensively assess the relationship between microbial populations within UC, the signaling pathways of pathogenic gut microbe therein and the inflammatory response, as well as to understand the effects of using PE&AFWE (poppy extract [Papaver nudicaule L.] and Artemisia frigida Willd. extract) on UC modulation.

METHODS

A UC mouse model was established by inducing SPF-grade C57BL/6 mice using dextrose sodium sulfate (DSS). Based on metagenomic sequencing to characterize the gut microbiome, the relationship between gut microbiota dysbiosis and gut microbiota was further studied using random forest and Bayesian network analysis methods, as well as histopathological analysis.

RESULTS

(1) We found that the 5 gut microbiota with the highest relative abundance of inflammatory bowel disease UC model gut microbiota were consistent with the top 5 ranked natural bacteria. There were three types of abundance changes in the model groups: increases (Chlamydiae/Proteobacteria and Deferribacteres), decreases (Firmicutes), and no significant changes (Bacteroidetes). The UC model group was significantly different from the control group, with 1308 differentially expressed species with abundance changes greater than or equal to 2-fold. (2) The proportion of the fecal flora in the UC group decreased by 37.5% in the Firmicutes and increased by 14.29% in the proportion of Proteobacteria compared to the control group before treatment. (3) The significantly enriched and increased signaling pathways screened were the 'arachidonic acid metabolic pathway' and the 'phagosomal pathway', which both showed a decreasing trend after drug administration. (4) Based on the causal relationship between different OTUs and the UC model/PE&AFWE administration, screening for directly relevant OTU networks, the UC group was found to directly affect OTU69, followed by a cascade of effects on OTU12, OTU121, OTU93, and OTU7, which may be the pathway of action that initiated the pathological changes in normal mice. (5) We identified a causal relationship between common differentially expressed OTUs and PE&AFWE and UC in the pre- and post-PE&AFWE-treated groups. Thereby, we learned that PE&AFWE can directly affect OTU90, after which it inhibits UC, inhibiting the activity of arachidonic acid metabolic pathway by affecting OTU118, which in turn inhibits the colonization of gut microbiota by OTU93 and OTU7. (6) Histopathological observation and scoring (HS) of the colon showed that there was a significant difference between the model group and the control group (p < 0.001), and that there was a significant recovery in both the sulfasalazine (SASP)and the PE&AFWE groups after the administration of the drug (p < 0.0001).

CONCLUSION

We demonstrated causal effects and inflammatory metabolic pathways in gut microbiota dysbiosis and IBD, with five opportunistic pathogens directly contributing to IBD. PE&AFWE reduced the abundance of proteobacteria in the gut microbiota, and histopathology showed significant improvement.

Comparison of fecal calprotectin levels and endoscopic scores for predicting relapse in patients with ulcerative colitis in remission

BACKGROUND

Although the usefulness of endoscopic scores, such as the Mayo Endoscopic Subscore (MES), Ulcerative Colitis Endoscopic Index of Severity (UCEIS), and Ulcerative Colitis Colonoscopic Index of Severity (UCCIS), and biomarkers such as fecal calprotectin (FC) for predicting relapse in ulcerative colitis (UC) has been reported, few studies have included endoscopic scores for evaluating the entire colon.

AIM

To compare the usefulness of FC value and MES, UCEIS, and UCCIS for predicting relapse in patients with UC in clinical remission.

METHODS

In total, 75 patients with UC in clinical and endoscopic remission who visited our institution between February 2019 and March 2022 were enrolled. The diagnosis of UC was confirmed based on the clinical presentation, endoscopic findings, and histology, according to the current established criteria for UC. Fecal samples were collected the day before or after the colonoscopy for measurement of FC. Endoscopic evaluations were performed using MES, UCEIS, and UCCIS. The primary outcome measure of this study was the assessment of the association between relapse within 12 mo and MES, UCEIS, UCCIS, and FC. The secondary outcome was the comparison between endoscopic scores and biomarkers in enrolled patients with UC with mucosal healing.

RESULTS

FC and UCCIS showed a significant correlation with UCEIS (r = 0.537, P < 0.001 and r = 0.957, P < 0.001, respectively). Receiver-operating characteristic analysis for predicting MES 0 showed that the area under the curve of UCCIS was significantly higher than that of FC (P < 0.01). During the 1-year observation period, 18 (24%) patients experienced a relapse, and both the FC and UCCIS of the relapse group were significantly higher than that of the remission group. The cut-off values for predicting relapse were set at FC = 323 mg/kg and UCCIS = 10.2. The area under the curve of the receiver-operating characteristic analysis for predicting relapse did not show a significant difference between FC and UCCIS. The accuracy of the endoscopic scores and biomarkers in predicting relapse was 86.7% for UCCIS, 85.3% for UCEIS, 76.0% for FC, and 73.3% for MES.

CONCLUSION

The three endoscopic scores and FC may predict UC relapse during clinical remission. Among these scores, UCEIS may be the most useful in terms of ease of evaluation and accuracy.

Histologic healing and factors associated with complete remission following conventional treatment in ulcerative colitis

BACKGROUND

Endoscopic and histological activity scores in ulcerative colitis (UC) are associated with clinical outcomes and have become important targets of clinical trials. However, these endpoints have been scarcely investigated in patients receiving only conventional treatment.

OBJECTIVE

We aimed to assess the deep and complete remission rates after 3 months of conventional treatment in patients with newly diagnosed UC with moderate to severe endoscopic activity. We also aimed to investigate whether selected clinical and biochemical variables at baseline were associated with complete remission status after 3 months.

DESIGN

This was a prospective cohort study.

METHODS

Newly diagnosed patients with active UC commencing 5-aminosalicylate, corticosteroid, and/or azathioprine treatment were consecutively included. Clinical, biochemical, endoscopic, and histological data were collected at baseline and after 3 months. Rates of clinical remission (Partial Mayo Score ⩽ 2), mucosal healing (Mayo Endoscopic Score ⩽ 1), and histologic healing (Nancy Index ⩽ 1) were determined. Deep remission was assessed as clinical remission plus mucosal healing and complete remission as deep remission plus histologic healing. Predictors of complete remission were identified by logistic regression.

RESULTS

A total of 180 patients were included in the study. Deep remission and complete remission occurred in 62.8% and 42.2% of patients, respectively. Thus, of patients in deep remission one-third had persistent histologic activity. Histologic activity in mucosally healed patients was associated with higher symptom scores and faecal calprotectin levels. Of baseline variables, less endoscopic distribution and disease activity showed strongest association with achieving complete remission, and limited distribution in combination with moderate activity gave highest odds for complete remission (odds ratio: 4.1, 95% confidence interval: 7.69-2.18).

CONCLUSION

In patients with mucosal healing, persistent histologic activity was a common finding and was associated with increased disease activity. Pancolitis and severe inflammatory activity at baseline were associated with lower complete remission rates.

The potential mechanism of huazhuojiedu decoction in the treatment of ulcerative colitis based on network pharmacology and experimental validation

Huazhuojiedu decoction (HZJDD), a traditional Chinese medicine prescription, has been clinically proven to be an effective treatment for ulcerative colitis (UC). However, the mechanism of HZJDD in the treatment of UC remains unclear. This study combined network pharmacology with experimental validation to explore the potential mechanism of HZJDD on UC. First, the relationship network diagrams between HZJDD and UC were established based on multiple databases. Then, the HZJDD-UC intersection genes target network was constructed and Gene Ontology-Biological processes (GO-BP) analysis was performed to discover the potential pharmacological mechanism. Finally, the results of GO-BP were verified in dextran sulfate sodium salt (DSS) induced UC rats. The network pharmacology results showed that 119 active components and 146 potential targets were screened for HZJDD, and six of the top 15 biological processes belonged to inflammatory response, cellular response to hypoxia, and cellular response to lipopolysaccharide (LPS). The GO-BP results indicated that the mechanism of HZJDD treatment of UC was related to inflammation, oxidative stress, and the regulation of LPS. Animal experiments showed that HZJDD could significantly reduce the disease activity index (DAI) score, improve colon length, and effectively repair the histomorphological and micromorphological changes in DSS-induced UC rats. Moreover, HZJDD reduced the expressions of CRP, TNF-α, IL-6, LPS, IL-1β, and IL-18; downregulated the activity of MDA; and upregulated the activities of CAT, GSH, and SOD in DSS-induced UC rats. Furthermore, HZJDD suppressed the expression of the NLRP3/caspase-1 signaling pathway at the gene and protein levels to inhibit pyroptosis. Network pharmacology and animal experiments showed that HZJDD exerted a therapeutic effect on DSS-induced UC rats by reducing inflammation, oxidative stress, and restraining the NLRP3/caspase-1 signaling pathway to inhibit pyroptosis.

Artemisinin Alleviates Intestinal Inflammation and Metabolic Disturbance in Ulcerative Colitis Rats Induced by DSS

Objective

This study is aimed to reveal the possible mechanisms of artemisinin in the treatment of ulcerative colitis (UC) through bioinformatics analysis and experimental verification in UC model rats.

Methods

Firstly, we searched two microarray data of the Gene Expression Omnibus (GEO) database to explore the differentially expressed genes (DEGs) between UC samples and normal samples. Then, we selected DEGs for gene ontology (GO) function enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. The acute UC model of rats was established by using 3.5% dextran sulfate sodium (DSS) for 10 days to verify the core pathway. Finally, we evaluated the therapeutic effect of artemisinin at the molecular level and used metabonomics to study the endogenous metabolites in the rat serum.

Results

We screened in the GEO database and selected two eligible microarray datasets, GSE36807 and GSE9452. We performed GO function and KEGG pathway enrichment analyses of DEGs and found that these DEGs were mainly enriched in the inflammatory response, immune response, and IL-17 and NF-κB signaling pathways. Finally, we verified the IL-17 signaling pathway and key cytokines, and ELISA and immunohistochemical results showed that artemisinin could downregulate the expression of proinflammatory cytokines such as IL-1β and IL-17 in the IL-17 signaling pathway and upregulate the expression of the anti-inflammatory cytokine PPAR-γ. Metabolomics analysis showed that 33 differential metabolites were identified in the artemisinin group (AG) compared to the model group (MG). Differential metabolites were mainly involved in alanine, aspartate, and glutamate metabolism and synthesis and degradation of ketone bodies.

Conclusion

In this study, we found that artemisinin can significantly inhibit the inflammatory response in UC rats and regulate metabolites and related metabolic pathways. This study provides a foundation for further research on the mechanism of artemisinin in the treatment of UC.