Oral 5-aminosalicylic acid for maintenance of remission in ulcerative colitis

Efficacy and safety of Xileisan combined with mesalazine for ulcerative colitis: A meta-analysis and trial sequential analysis

BACKGROUND

The benefits and risks of Xileisan (XLS) in the treatment of ulcerative colitis (UC) remain unclear.

AIM

The present study aimed to evaluate the efficacy and safety of the combination of XLS and mesalazine when treating UC.

METHODS

We searched eight databases for clinical trials evaluating the combination of XLS and mesalazine in the treatment of UC, up to January 2024. Meta-analysis and trial sequential analysis (TSA) were performed using Revman 5.3 and TSA 0.9.5.10 beta, respectively.

RESULTS

The present study included 13 clinical studies involving 990 patients, of which 501 patients received XLS combined with mesalazine while 489 patients received mesalazine alone. The meta-analysis showed that, in terms of efficacy, the combination of XLS and mesalazine significantly improved the clinical efficacy rate by 22% [risk ratio (RR) = 1.22; 95%CI: 1.15-1.28; P < 0.00001] and mucosal improvement rate by 25% (RR = 1.25; 95%CI: 1.12-1.39; P = 0.0001), while significantly reducing the duration of abdominal pain by 2.25 days [mean difference (MD) = -2.25; 95%CI: -3.35 to -1.14; P < 0.0001], diarrhea by 2.06 days (MD = -2.06; 95%CI: -3.92 to -0.20; P = 0.03), hematochezia by 2.32 days (MD = -2.32; 95%CI: -4.02 to -0.62; P = 0.008), tumor necrosis factor alpha by 16.25 ng/mL (MD = -16.25; 95%CI: -20.48 to -12.01; P < 0.00001), and interleukin-6 by 14.14 ng/mL (MD = -14.14; 95%CI: -24.89 to -3.39; P = 0.01). The TSA indicated conclusiveness in the meta-analysis of the efficacy endpoints. In terms of safety, the meta-analysis revealed that the combination of XLS and mesalazine did not increase the occurrence of total and gastrointestinal adverse events, abdominal distension, and erythema (P > 0.05). The TSA showed non conclusive findings in the meta-analysis of the safety endpoints. Harbord's test showed no publication bias (P = 0.734).

CONCLUSION

Treatment with XLS alleviated the clinical symptoms, intestinal mucosal injury, and inflammatory response in patients with UC, while demonstrating good safety.

Exploring inflammatory bowel disease therapy targets through druggability genes: a Mendelian randomization study

Background

Inflammatory bowel disease is an incurable group of recurrent inflammatory diseases of the intestine. Mendelian randomization has been utilized in the development of drugs for disease treatment, including the therapeutic targets for IBD that are identified through drug-targeted MR.

Methods

Two-sample MR was employed to explore the cause-and-effect relationship between multiple genes and IBD and its subtypes ulcerative colitis and Crohn's disease, and replication MR was utilized to validate this causality. Summary data-based Mendelian randomization analysis was performed to enhance the robustness of the outcomes, while Bayesian co-localization provided strong evidential support. Finally, the value of potential therapeutic target applications was determined by using the estimation of druggability.

Result

With our investigation, we identified target genes associated with the risk of IBD and its subtypes UC and CD. These include the genes GPBAR1, IL1RL1, PRKCB, and PNMT, which are associated with IBD risk, IL1RL1, with a protective effect against CD risk, and GPX1, GPBAR1, and PNMT, which are involved in UC risk.

Conclusion

In a word, this study identified several potential therapeutic targets associated with the risk of IBD and its subtypes, offering new insights into the development of therapeutic agents for IBD.

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.

Therapeutic effect of 5-ASA and hesperidin-loaded chitosan/Eudragit® S100 nanoparticles as a pH-sensitive carrier for local targeted drug delivery in a rat model of ulcerative colitis

Ulcerative colitis (UC) is an idiopathic disease characterized by colonic mucosal tissue destruction secondary to an excessive immune response. We synthesized pH-sensitive cross-linked chitosan/Eudragit® S100 nanoparticles (EU S100/CS NPs) as carriers for 5-aminosalicylic acid (5-ASA) and hesperidin (HSP), then conducted in-vitro and in-vivo studies and evaluated the therapeutic effects. In-vitro analysis revealed that the 5-ASA-loaded EU S100/CS NPs and the HSP-loaded EU S100/CS NPs had smooth and curved surfaces and ranged in size between 250 and 300 nm, with a zeta potential of 32 to 34 mV. FTIR analysis demonstrated that the drugs were loaded on the nanoparticles without significant alterations. The loading capacity and encapsulation efficiency of loading 5-ASA onto EU S100/CS NPs were 25.13 % and 60.81 %, respectively. Regarding HSP, these values were 38.34 % and 77.84 %, respectively. Drug release did not occur in simulated gastric fluid (SGF), while a slow-release pattern was recorded for both drugs in simulated intestinal fluid (SIF). In-vivo macroscopic and histopathological examinations revealed that both NPs containing drugs significantly relieved the symptoms of acetic acid (AA)-induced UC in Wistar rats. We conclude that the synthesized pH-sensitive 5-ASA/EU S100/CS NPs and HSP/EU S100/CS NPs offer promise in treating UC.

Activation of mucosal insulin receptor exacerbates intestinal inflammation by promoting tissue resident memory T cells differentiation through EZH2

BACKGROUND

Inflammatory Bowel Diseases (IBD), an autoimmune disease characterised by abnormal intestinal immunity, are related to vital morbidity around the world. However, therapeutic agents for IBD have not achieved desired benefit. Exploring new therapeutic targets for IBD, especially based on its abnormally intestinal immunity, could alleviate the flare-up and worsening of IBD. Tissue resident memory T cells (TRM) are core of multiple autoimmune diseases, including IBD. However, the mechanism of TRM differentiation remains to be investigated.

METHODS

The alterations in mRNA and lncRNA profile of intestinal intraepithelial lymphocytes (IELs), the largest component of intestinal TRM, were analyzed in DSS-induced chronic colitis. Based on it, we examined the function of rectal insulin instillation in a dextran sodium sulfate (DSS) induced chronic colitis. Furthermore, we investigated the downstream-target of the insulin pathway-EZH2 and the crucial role of EZH2 in intestinal tissue resident memory T cell differentiation by utilizing EZH2fl/flCD4cre mice.

RESULTS

Insulin receptor (INSR) expression was found to be significantly reduced. Activation of mucosal insulin pathway by rectal insulin instillation exacerbated colitis by disrupting IELs subgroups and up-regulating TNF-ɑ and IL-17 expression. Rectal insulin instillation promoted EZH2 expression and EZH2 inhibition alleviated chronic colitis. EZH2fl/flCD4cre mice restored the normal IEL subgroups and suppressed TNF-ɑ and IL-17 expression, exhibiting alleviated colitis. IELs from EZH2fl/flCD4cre mice exhibit significant changes in TRM related phenotype. CD4+TRM was significantly increased in chronic colitis and decreased in EZH2fl/flCD4cre mice.

CONCLUSION

Insulin receptor of intestinal mucosal T-cells could promote intestinal TRM differentiation via EZH2. Our discoveries suggest that therapies targeting colonic INSR and EZH2 could be potential treatment for IBD based on its regulatory effects on TRM. Insulin receptor inhibitors rather than insulin should be applied during colitis-active phase. In addition, EZH2 shows to be a downstream signal of the insulin pathway and EZH2 inhibitor could alleviating intestinal inflammation. However, the critical role of EZH2 in TRM differentiation restricts the anti-tumor effects of EZH2 inhibitor in vivo.

Protective effect of Melissa officinalis against acetic acid-induced ulcerative colitis in rat models: an experimental study

Background

Inflammation and oxidative activities within the gut play major roles in the pathogenesis of ulcerative colitis (UC). We aimed to determine the effect of Melissa officinalis, an antioxidant and anti-inflammatory agent, on the colon histological characteristics in acetic acid (AA)-induced UC in rat models.

Methods

Thirty-six male rats with AA-induced colitis were divided into 5 groups: no treatment (AA); daily treatment with 300 mg/kg Melissa officinalis orally (MO) and rectally (MR); and 100 mg/kg mesalamine orally (AO) and rectally (AR). Macroscopic and histopathological evaluation of the colon, along with a biochemical laboratory evaluation, were performed 10 days after UC induction.

Results

All treatment groups demonstrated lower macroscopic grading scores compared to the AA group. After treatment with MO, 42.9% of cases demonstrated no macroscopic changes, while 14.3% demonstrated only mucosal erythema. In the MR group 28.6% of rats had no changes in their mucosal lining and 28.6% had only mucosal erythema. Following histopathological evaluation, the AO group had lower scores regarding the severity of ulcer, inflammation, destruction, crypt abscess, and disorganization compared to the MO group. (P=0.02) The MR group demonstrated lower microscopic scores compared to the MO group, and also lower macroscopic scores compared to the AR group, although not significantly (P>0.05).

Conclusions

Both oral and topical administration of Melissa officinalis have satisfactory healing properties compared to mesalamine, with topical route having better results. Therefore, further studies are needed to establish the benefit of Melissa officinalis administration (both orally and topically) within a UC treatment protocol.

Electroacupuncture for ulcerative colitis patients: A meta-analysis and acupoints selection study

Objective

To evaluate the efficacy and safety of electroacupuncture (EA) on ulcerative colitis (UC) and explore the influence of EA parameters and acupoint compatibility to optimize the clinical treatment plan.

Methods

After searching eight databases, data were extracted and analyzed to determine the quality and bias of the study's methodological design, and randomized controlled trial (RCT) datas were meta-analyzed.

Results

Twelve studies that meet the criteria were included. The results of meta-analysis indicated that, compared with the control group, experimental group had better clinical efficacy [RR = 1.27, 95%CI = (1.19, 1.36), P < 0.01], Other indicators such as cure rate [RR = 1.73, 95%CI = (1.43, 2.09), P < 0.01], effective rate of mucosal lesions under enteroscopy [RR = 1.24, 95%CI = (1.11, 1.38), P < 0.01], serum inflammatory factor TNF-α [MD = -41.11, 95%CI = (-46.01, 36.22), P < 0.01] were significantly better than those in the control group. Sixteen acupoints on the Ren, Bladder, Stomach, Spleen, and Liver meridians were used 74 times. RN4-ST25 is the most compatible acupoints.

Conclusion

The clinical efficacy of EA in treating UC is superior than the control group's, and it has curative effects in terms of cure rate, efficacy of mucosal lesions under colonoscopy, serum inflammatory factors, and Traditional Chinese Medicine (TCM) syndrome scores. Combining acupoints of the Bladder, Stomach, and Ren meridians and using dense wave for 30 min each time for more than 6 weeks may be optimal for UC patients.

Regulatory effect of lactulose on intestinal flora and serum metabolites in colitis mice: In vitro and in vivo evaluation

Lactulose is a common component in foods. However, the effect of lactulose on intestinal flora and overall metabolic levels remains unclear. Therefore, this study aims to explore the regulative role of lactulose on intestinal flora and serum metabolites via in vitro simulated colonic fermentation model and in vivo colitis mouse model. The results showed that lactulose significantly enriched beneficial bacteria including Dubosiella and Bifidobacterium, and reduced pathogenic bacteria such as Fusobacterium. Moreover, lactulose significantly inhibited dextran sodium sulfate-induced body weight loss, colon shortening, colonic inflammatory infiltration, and pro-inflammatory cytokines IL-6, TNF-α, IL-17, and IL-1β. Lactulose significantly affected serum metabolome in colitis mice and total 24 metabolites representing a high inter-group difference were obtained. Correlation analysis revealed that the changes in serum metabolites were closely associated with the role of intestinal flora, and thus affected phenotypic indicators. Our study provides a reference for nutritional characteristics and application scenarios of dietary lactulose.

The Impacts of Fecal Microbiota Transplantation from Same Sex on the Symptoms of Ulcerative Colitis Patients

We aimed to compare the clinical efficacy of fecal microbiota transplantation (FMT) from the same sex on ulcerative colitis (UC) patients. A total of 272 UC patients were selected in the prospective clinical study, which incorporated four distinct groups, each comprising male and female patients, who were either receiving FMT or placebo, respectively. FMT was performed by sending the gut microbiota of healthy female or male adolescents to the same gender patients via gastroscope three times (one time/three weeks), and a placebo was used with an equal volume of saline. Abdominal pain, diarrhea, thick bloody stool, intestinal mucosal lesion, and Mayo scores were measured. Self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were evaluated. The changes of intestinal flora were detected by the 16S rRNA sequencing. FMT reduced the scores of diarrhea, abdominal pain, mucosal lesion, and Mayo, SAS, and SDS in UC patients compared to the placebo group (p < 0.05). Clostridiales and Desulfovibrionaceae were dominant in gut microbiota from male patients and were reduced after FMT. Meanwhile, the abundance of Prevotella, Lactobacillus, and Bifidobacterium was increased in the male group. Female patients had a higher abundance of Escherichia-Shigella, Desulfovibrionaceae, and Staphylococcaceae before FMT, and it was reduced after FMT. Meanwhile, the abundance of Porphyromonadaceae, Prevotella, Lactobacillus, and Bifidobacterium was increased in the female group. There were no significant changes for the species in the corresponding placebo groups. FMT improved the UC symptoms of male and female patients, which may be associated with different gut microbiota changes.

Probiotics for the treatment of ulcerative colitis: a review of experimental research from 2018 to 2022

Ulcerative colitis (UC) has become a worldwide public health problem, and the prevalence of the disease among children has been increasing. The pathogenesis of UC has not been elucidated, but dysbiosis of the gut microbiota is considered the main cause of chronic intestinal inflammation. This review focuses on the therapeutic effects of probiotics on UC and the potential mechanisms involved. In animal studies, probiotics have been shown to alleviate symptoms of UC, including weight loss, diarrhea, blood in the stool, and a shortened colon length, while also restoring intestinal microecological homeostasis, improving gut barrier function, modulating the intestinal immune response, and attenuating intestinal inflammation, thereby providing theoretical support for the development of probiotic-based microbial products as an adjunctive therapy for UC. However, the efficacy of probiotics is influenced by factors such as the bacterial strain, dose, and form. Hence, the mechanisms of action need to be investigated further. Relevant clinical trials are currently lacking, so the extension of animal experimental findings to clinical application requires a longer period of consideration for validation.

Chimonanthus salicifolius extract alleviates DSS-induced colitis and regulates gut microbiota in mice

Ulcerative colitis is a chronic and recurrent gastrointestinal intestinal disease accompanied by inflammatory disorders, immunologic inadequacy, and intestinal flora dysbiosis, and current therapeutic pharmaceuticals have limited side effects. In this study, we revealed the extraction method of Chimonanthus salicifolius, analyzed the main component, compared the effect of its extract, Lactobacillus, and conventional drugs with different properties on DSS (dextran sodium sulfate)-induced colitis, and indicated extract regulatory properties of inestinal flora. A colitis model was established on experimental design, and BALB/c mice (male, 7 weeks old) were randomly assigned to five groups (n = 10): control, DSS model, Chimonanthus salicifolius extract (CSE), Lactobacillus rhamnosus GG (LGG), and 5-aminosalicylic acid (5-ASA) groups. The three treatments could alleviate the symptoms and remit inflammation induced by DSS, in which CSE and LGG groups could both decrease the proinflammatory cytokine IL-6, IL-8, and TNF-α levels and increase anti-inflammatory cytokines IL-10 and TGF-β. The CSE intervention significantly promoted the higher production of butyric acid than LGG and 5-ASA groups (p < .05) after DSS challenge. Analysis of intestinal flora showed that CSE administration remarkably decreased the relative abundance of pathogenic bacteria Heliobacteriaceae and Peptococcaceae and exhibited higher abundance of Lactobacillaceae and Bifidobacterium than LGG in intestinal tract of mice (p < .05). These findings indicated that Chimonanthus salicifolius extract may have been beneficial for preventing and treating colitis.

Medication Formulation Preference of Mild and Moderate Ulcerative Colitis Patients: a European Survey

Introduction

Patient adherence is a major challenge for the successful management of any chronic disease, and ulcerative colitis (UC) is no exception. Patient adherence is closely related to patient preference of medication and formulation used.

Aim

The aim of this study was to investigate patient and physician perspectives around UC treatment preference.

Methods

This study was conducted in France, Germany, Spain, and the UK. Physicians and UK inflammatory bowel disease (IBD) nurses answered an online questionnaire. In addition, adult mild-to-moderate UC patients, treated with oral mesalazine, were invited to answer a 30-min online survey which included a conjoint exercise.

Results

400 patients, 160 physicians, and 20 IBD nurses participated in the survey. 68% of patients were taking tablets and 32% granules. Physicians stated that from their perspective patients are more adherent to tablets than granules (76% vs. 24%), patients tended to have better relief of symptoms with tablets (69% vs. 31%), and patients found tablets to be the most convenient formulation (61% vs. 39%). From the patients' perspective, when questioned which formulation they prefer, 58% answered tablets, 37% granules, and 5% none of these. When patients were asked about some negative attributes of tablets, the highest agreement was for "I would like to take fewer each day" (6.1/10) and "I wish I could take fewer at a time" (5.4/10).

Conclusions

The majority of UC patients in this survey prefer the tablet formulation. A high strength tablet overcoming the high pill burden could be a good solution to address patient expectations.

De-escalation of Therapy in Patients with Quiescent Inflammatory Bowel Disease

Inflammatory bowel disease is a chronic disease of unknown origin that requires long-term treatment. The optical duration of maintenance treatment once remission has been achieved remains unclear. When discussing a de-escalation strategy, not only the likelihood of relapse but also, the outcome of retreatment for relapse after de-escalation should be considered. Previous evidence has demonstrated controversial results for risk factors for relapse after de-escalation due to the various definitions of remission and relapse. In fact, endoscopic or histologic remission has been suggested as a treatment target; however, it might not always be indicative of a successful drug withdrawal. For better risk stratification of relapse after de-escalation, it may be necessary to evaluate both the current and previous treatments. Following de-escalation, biomarkers should be closely monitored. In addition to the risk of relapse, a comprehensive understanding of the overall outcome, such as the long-term safety, patient quality of life, and impact on healthcare costs, is necessary. Therefore, a shared decision-making with patients on a case-by-case basis is imperative.

Significance of 5-Aminosalicylic Acid Intolerance in the Clinical Management of Ulcerative Colitis

BACKGROUND

Two major types of 5-aminosalicylic acid (5-ASA)-containing preparations, namely, mesalazine/5-ASA and sulfasalazine (SASP), are currently used as first-line therapy for ulcerative colitis. Recent reports show that optimization of 5-ASA therapy is beneficial for both patient outcomes and healthcare costs. Although 5-ASA and SASP have good efficacy and safety profiles, clinicians occasionally encounter patients who develop 5-ASA intolerance.

SUMMARY

The most common symptoms of acute 5-ASA intolerance syndrome are exacerbation of diarrhea, fever, and abdominal pain. Patients who discontinue 5-ASA therapy because of intolerance have a higher risk of adverse clinical outcomes, such as hospital admission, colectomy, need for advanced therapies, and loss of response to anti-tumor necrosis factor (TNF) biologics. When patients develop symptoms of 5-ASA intolerance, the clinician should consider changing the type of 5-ASA preparation. Recent genome-wide association studies and meta-analyses have shown that 5-ASA allergy is associated with certain single-nucleotide polymorphisms. Although there are no modalities or biomarkers for diagnosing 5-ASA intolerance, the drug-induced lymphocyte stimulation test can be used to assist in the diagnosis of acute 5-ASA intolerance syndrome with high specificity and low sensitivity. This review presents a general overview of 5-ASA and SASP in the treatment of inflammatory bowel disease and discusses the latest insights into 5-ASA intolerance.

KEY MESSAGES

5-ASA is used as first-line therapy for ulcerative colitis. Optimization of 5-ASA may be beneficial for patient outcomes and healthcare systems. Acute 5-ASA intolerance syndrome is characterized by diarrhea, fever, and abdominal pain. Periodic renal function monitoring is recommended for patients receiving 5-ASA.

Bromodomain-containing protein 4 (BRD4): a key player in inflammatory bowel disease and potential to inspire epigenetic therapeutics

INTRODUCTION

Inflammatory bowel diseases (IBDs) are debilitating chronic inflammatory disorders with increasing prevalence worldwide. Epigenetic regulator bromodomain-containing protein 4 (BRD4) is critical in controlling gene expression of IBD-associated inflammatory cytokine networks. BRD4 as a promising therapeutic target is also tightly associated with many other diseases, such as airway inflammation and fibrosis, cancers, infectious diseases and central nervous system disorders.

AREAS COVERED

This review briefly summarized the critical role of BRD4 in the pathogenesis of IBDs and the current clinical landscape of developing bromodomain and extra terminal domain (BET) inhibitors. The challenges and opportunities as well as future directions of targeting BRD4 inhibition for potential IBD medications were also discussed.

EXPERT OPINION

Targeting BRD4 with potent and specific inhibitors may offer novel effective therapeutics for IBD patients, particularly those who are refractory to anti-TNFα therapy and IBD-related profibrotic. Developing highly specific BRD4 inhibitors for IBD medications may help erase the drawbacks of most current pan-BET/BRD4 inhibitors, such as off-target effects, poor oral bioavailability, and low gut mucosal absorbance. Novel strategies such as combinatorial therapy, BRD4-based dual inhibitors and proteolysis targeting chimeras (PROTACs) may also have great potential to mitigate side effects and overcome drug resistance during IBD treatment.

A broad cuproptosis landscape in inflammatory bowel disease

Background

Cuproptosis, a genetic process of copper-dependent cell death linked to mitochondria respiration, demonstrates its correlation with inhibiting tumoral angiogenesis and motility. Recent studies have developed systematic bioinformatics frameworks to identify the association of cuproptosis with tumors but any non-neoplastic diseases. Therefore, against the background of an increased incidence of inflammatory bowel disease (IBD), the landscape of cuproptosis regulation in IBD is a critical need to be investigated.

Methods

The differentially expressed cuproptosis-related genes (DECRGs) were identified with human sequencing profiles for four inflammatory digestive disorders. Another four independent IBD datasets from GEO were used as a validation cohort. And experimental mice model provides another validation method. Using single sample gene set enrichment analysis (ssGSEA), receiver operating characteristic (ROC) curve, CIBERSORT, and consensus clustering algorithms, we explored the association between immune score and cuproptosis-related genes, as well as the diagnostic value of these genes. Molecular docking screened potential interaction of IBD drugs with the structural regulator by Autodock Vina.

Results

Cuproptosis-related regulators exhibited extensive differential expression in Crohn's Disease (CD), Ulcerative Colitis (UC), Celiac Disease (CEL), and IBD-induced cancer (IBD-CA) that share common differential genes (PDHA1, DBT, DLAT, LIAS). The differential expression of DECRGs was reverified in the validated cohort and immunohistochemistry assay. Moreover, the cell signaling pathways and ontology mainly focused on the mitochondrial respiratory function, which was highly enriched in Gene set enrichment analysis (GSEA). According to ssGSEA and ROC, when considering the four regulators, which showed robust association with immune infiltration in IBD, the area under the ROC (AUC) was 0.743. In addition, two clusters of consensus clustering based on the four regulators exhibit different immune phenotypes. According to molecular docking results, methotrexate gained the highest binding affinity to the main chain of key cuproptosis-related regulators compared with the remaining ten drugs.

Conclusion

Cuproptosis-related regulators were widely linked to risk variants, immune cells, immune function, and drug efficacy in IBD. Regulation of cuproptosis may deeply influence the occurrence and development of patients with IBD.

The insoluble excretion of multi-matrix system mesalazine preparations in patients with ulcerative colitis

BACKGROUND

Multi-matrix mesalazine (MMX) is an important treatment for ulcerative colitis (UC); however, it is often excreted intact, which increases the risk of relapse. This study aimed to clarify the risk factors for insoluble MMX excretion.

METHODS

The subjects were 102 UC patients who were newly prescribed MMX alone to induce remission. Their stools were evaluated on the Bristol Stool Form Scale (BSFS), the presence/absence of insoluble MMX excretion was investigated in interviews, and defecation frequency at the start of treatment and disease type were retrospectively investigated by examining their medical records.

RESULTS

The insoluble excretion rate (IER) was 14.7%. It tended to be higher in the patients with left-sided colitis or extensive colitis, although the differences among the disease types were not significant (p = 0.053). The mean defecation frequency of the patients that reported insoluble MMX excretion was significantly higher than that of the patients that did not report it (6.27 ± 5.28 vs. 3.69 ± 3.17, p < 0.05). The IER tended to be higher among the patients with soft stools (4.5%, 21.9%, and 23.1% in those with BSFS scores of ≤ 4, 5, and ≥ 6, respectively). In ROC analysis of defecation frequency, ≥ 3.5 defecations was found to exhibit sensitivity and specificity of 66.7% and 65.5%, respectively, for predicting insoluble MMX excretion.

CONCLUSIONS

The likelihood of insoluble MMX excretion is influenced by defecation frequency and the extent of inflammation. It is important to keep the possibility of insoluble excretion in mind when prescribing MMX.

No increased risk of flare in ulcerative colitis patients in corticosteroid-free remission after stopping 5-aminosalicylic acid: A territory-wide population-based study

BACKGROUND AND AIM

Whether 5-aminosalicylic acid (ASA) can be stopped in patients with stable ulcerative colitis (UC) remains unclear. We aimed to examine whether 5-ASA can be safely withdrawn in UC patients who have been in corticosteroid-free clinical remission for ≥ 1 year.

METHODS

This is a retrospective cohort study using territory-wide healthcare database in Hong Kong. Primary outcome was development of UC flare, defined as new corticosteroid use or UC-related hospitalizations within 5 years. UC patients on oral 5-ASA ≥ 2 g daily for ≥ 1 year with C-reactive protein (CRP) < 10 mg/dL and no 5-ASA dosage escalation, UC-related hospitalization or corticosteroid use in the past year were included. Patients on biological agents were excluded. Patients were classified as "stopping" if 5-ASA was withdrawn for ≥ 90 days within follow-up period. We performed multivariable Cox regression models adjusting for demographics, blood parameters and immunosuppressants used. Adjusted hazard ratio (aHR) with 95% confidence interval (CI) was reported comparing stopping and continuous-use groups.

RESULTS

A total of 1408 patients were included with a median follow-up duration of 41.8 months (interquartile range [IQR]: 17.2-60.0 months). Stopping 5-ASA was not associated with an increased risk of UC flare (aHR 0.91; 95% CI 0.64-1.31; P = 0.620). A higher CRP levels at the time of stopping 5-ASA (aHR 1.15; 95% CI: 1.01-1.30; P = 0.037) were associated with increased risk of flare.

CONCLUSION

Stopping 5-ASA in UC patients in corticosteroid-free remission for ≥ 1 year was not associated with increased risk of flare. Future prospective trials should evaluate the role of stopping 5-ASA in stable UC patients.

Gut Microbiota Associated with Clinical Relapse in Patients with Quiescent Ulcerative Colitis

The microbiota associated with relapse in patients with quiescent ulcerative colitis (qUC) remains unclear. Our objective was to analyze the fecal microbiota of Japanese patients with qUC and identify the relapse-associated microbiota. In this study, 59 patients with qUC and 59 healthy controls (HCs) were enrolled (UMIN 000019486), and their fecal microbiota was compared using 16S rRNA gene amplicon sequencing. We followed their clinical course up to 3.5 years and analyzed the relapse-associated microbiota. Potential functional changes in the fecal microbiota were evaluated using PICRUSt software and the Kyoto Encyclopedia of Genes and Genomes database. There were significant differences in fecal microbiota diversity between HC and qUC subjects, with 13 taxa characterizing each subject. Despite no significant difference in variation of microbiota in a single sample (α diversity) between patients in sustained remission and relapsed patients, the variation in microbial communities between samples (β diversity) was significantly different. Prevotella was more abundant in the sustained remission patients, whereas Faecalibacterium and Bifidobacterium were more abundant in the relapsed patients. We clustered the entire cohort into four clusters, and Kaplan–Meier analysis revealed the subsequent clinical course of each cluster was different. We identified 48 metabolic pathways associated with each cluster using linear discriminant analysis effect size. We confirmed the difference in microbiota between patients with qUC and HCs and identified three genera associated with relapse. We found that the clusters based on these genera had different subsequent clinical courses and activated different metabolic pathways.

Sulfasalazine exacerbates Angiotensin II induced cardiac remodeling by activating Akt signal pathway

A thorough understanding of the pathological process underlying hypertension-induced cardiac remodeling may help in prevention and treatment of heart failure. Angiotensin II (Ang II) results in cardiac fibrosis and hypertrophy partly through activation of inflammation, which increases the fibroblasts and promotes extracellular matrix production. Sulfasalazine (SASP) has evident anti-inflammatory effects and pharmacological functions on autoimmune disease. The roles of SASP in the cardiac remodeling remain unknow. In this study, we established Ang II-induced cardiac remodeling mice model and then treated with SASP. Blood pressure, cardiac pump function, and pathological changes of cardiac remodeling were analyzed in these mice. To explore the mechanism, phosphorylated Akt was detected in vivo and vitro. In this study, we found that SASP aggravated cardiac dysfunction, hypertrophy and fibrosis after Ang II infusion. In addition, SASP activated Akt in Ang II-remodeled mouse hearts and cardiac cells. Our findings indicate that independent of anti-inflammatory property, SASP exacerbates Ang II-induced cardiac remodeling by activation of Akt signaling pathway.

An Update on Current Pharmacotherapeutic Options for the Treatment of Ulcerative Colitis

The main goals of Ulcerative Colitis (UC) treatment are to both induce and maintain the clinical and endoscopic remission of disease, reduce the incidence of complications such as dysplasia and colorectal carcinoma and improve quality of life. Although a curative medical treatment for UC has not yet been found, new therapeutic strategies addressing specific pathogenetic mechanisms of disease are emerging. Notwithstanding these novel therapies, non-biological conventional drugs remain a mainstay of treatment. The aim of this review is to summarize current therapeutic strategies used as treatment for ulcerative colitis and to briefly focus on emerging therapeutic strategies, including novel biologic therapies and small molecules. To date, multiple therapeutic approaches can be adopted in UC and the range of available compounds is constantly increasing. In this era, the realization of well-designed comparative clinical trials, as well as the definition of specific therapeutic models, would be strongly suggested in order to achieve personalized management for UC patients.

The Influence of Acupuncture Parameters on Efficacy and the Possible Use of Acupuncture in Combination with or as a Substitute for Drug Therapy in Patients with Ulcerative Colitis

Background. Ulcerative colitis (UC) is an inflammatory disease of the colonic mucosa, which is accompanied by chronic, idiopathic characteristics. Acupuncture may be an effective therapy for UC. Here we focused on manual acupuncture and electroacupuncture (MA/EA), two widely used and studied acupuncture interventions, to probe the effects of acupuncture parameters on clinical efficacy in patients with UC and the use of MA/EA alone or with other drugs to support their wider adoption in clinical practice. Methods. The PubMed, Cochrane Library, Web of Science, Embase, China National Knowledge Infrastructure Database, and Wanfang databases were searched from inception to April 27, 2021. Randomized clinical trials (RCTs) published in Chinese or English were included, and subgroup analyses were performed according to acupuncture parameter, acupuncture type, and control medicine type. The risk of bias was assessed using the Cochrane Risk of Bias tool and modified Jadad scale, and Review Manager 5.4 and Stata 14.0 were used to perform a meta-analysis. Sources of heterogeneity were explored; sensitivity analysis was performed; and the GRADE methodology was used to assess the evidence level. Results. Sixteen studies (1454 individuals) were included. Retention of the needle [10–30 minutes (RR 1.18, 95% CI [1.11, 1.26], $P<0.01$ ; heterogeneity: χ2 = 6.25, df = 6 ( $P=0.40$ ), I2 = 4%)], the frequency of MA [once every other day (RR 1.21, 95% CI [1.08, 1.35], $P<0.01$ ; heterogeneity: χ2 = 0.80, df = 1 ( $P=0.37$ ), I2 = 0%)], and the length of treatment [8 weeks (RR 1.35, 95% CI [1.01, 1.81], $P=0.04$ )] improved clinical efficacy at the end of treatment compared with medications alone. MA (RR 1.18, 95% CI [1.11, 1.25], $P<0.01$ ; heterogeneity: χ2 = 6.19, df = 7 ( $P=0.52$ ), I2 = 0%) increased clinical efficacy compared with medications. Furthermore, MA plus medications (RR 1.26, 95% CI [1.13, 1.40], $P<0.01$ ; heterogeneity: χ2 = 0.95, df = 2 ( $P=0.62$ ), I2 = 0%) and EA plus medications (RR 1.36, 95% CI [1.13, 1.63], $P<0.01$ ; heterogeneity: χ2 = 0.13, df = 1 ( $P=0.72$ ), I2 = 0%) both dramatically improved clinical efficacy. The clinical efficacy of MA plus mesalazine or MA plus metronidazole and sulfasalazine was greater than with mesalazine or metronidazole and sulfasalazine alone. Similarly, EA plus sulfasalazine was more effective than sulfasalazine alone. MA/EA resulted in fewer adverse reactions than medical therapies. The use of MA plus medications significantly reduced Baron scores. GRADE evaluations indicated that the evidence strength was moderate to low but mostly low. Conclusions. Our study provides the latest evidence to allow us to speculate about the possible optimal MA parameters to treat patients with UC. The low number of adverse reactions and high efficacy make MA/EA a possible supplement to or replacement for traditional UC drugs. The variable parameter settings preferred by patients and acupuncturists may be an important factor limiting the wider clinical deployment of acupuncture as a potential UC therapy.

Dapsone Azo-Linked with Two Mesalazine Moieties Is a "Me-Better" Alternative to Sulfasalazine

Dapsone (DpS) is an antimicrobial and antiprotozoal agent, especially used to treat leprosy. The drug shares a similar mode of action with sulfonamides. Additionally, it possesses anti-inflammatory activity, useful for treating autoimmune diseases. Here, we developed a “me-better” alternative to sulfasalazine (SSZ), a colon-specific prodrug of mesalazine (5-ASA) used as an anti-inflammatory bowel diseases drug; DpS azo-linked with two molecules of 5-ASA (AS-DpS-AS) was designed and synthesized, and its colon specificity and anti-colitic activity were evaluated. AS-DpS-AS was converted to DpS and the two molecules of 5-ASA (up to approximately 87% conversion) within 24 h after incubation in the cecal contents. Compared to SSZ, AS-DpS-AS showed greater efficiency in colonic drug delivery following oral gavage. Simultaneously, AS-DpS-AS substantially limited the systemic absorption of DpS. In a dinitrobenzene sulfonic acid-induced rat colitis model, oral AS-DpS-AS elicited better efficacy against rat colitis than oral SSZ. Moreover, intracolonic treatment with DpS and/or 5-ASA clearly showed that combined treatment with DpS and 5-ASA was more effective against rat colitis than the single treatment with either DpS or 5-ASA. These results suggest that AS-DpS-AS may be a “me-better” drug of SSZ with higher therapeutic efficacy, owing to the combined anti-colitic effects of 5-ASA and DpS.

Cinacalcet Targets the Neurokinin-1 Receptor and Inhibits PKCδ/ERK/P65 Signaling to Alleviate Dextran Sulfate Sodium-Induced Colitis

Objective: Inflammatory bowel disease is an immune-mediated chronic inflammatory disease of the gastrointestinal tract for which curative drugs are currently not available. This study was performed to assess the therapeutic effects of cinacalcet on dextran sulfate sodium (DSS)-induced colitis. Methods: Primary macrophages obtained from bone marrow and the macrophage cell line RAW264.7 were used to examine the inhibitory effect of cinacalcet on cytokine production, the PKCδ/ERK/P65 signaling pathway, and NF-κB P65 translocation. Colitis was induced using DSS to assess the treatment effect of cinacalcet. Bioinformatics approaches were adopted to predict potential targets of cinacalcet, and a drug affinity responsive target stability (DARTs) assay was performed to confirm binding between cinacalcet and potential target. Results: In vivo analysis showed that cinacalcet reduced the disease activity score, prevented shortening of the colon, diminished inflammatory cell infiltration, and protected the structural integrity of the intestinal wall. Cinacalcet also reduced production of the inflammatory cytokines TNFα, IL-1β, and IL-6 in the colon and sera of mice with DSS-induced colitis. In vitro studies revealed that cinacalcet suppressed the translocation of P65 and inhibited production of the inflammatory cytokines IL-1β and IL-6. Mechanistic studies revealed that the target of cinacalcet was neurokinin-1 receptor (NK1R) and their binding was confirmed by a DARTs assay. Furthermore, the inhibition of NK-κB P65 activation was found to occur via the suppression of PKCδ/ERK/P65 signaling mediated by cinacalcet. Conclusion: Cinacalcet inhibits the activation of NF-κB and reduces the production of inflammatory cytokines by suppressing the PKCδ/ERK/P65 signaling pathway via targeting NK1R, suggesting that it can be used to treat inflammatory diseases, particularly colitis.

Photodynamic Therapy of Novel Photosensitizer Ameliorates TNBS-Induced Ulcerative Colitis via Inhibition of AOC1

Ulcerative colitis (UC), a chronic, nonspecific inflammatory bowel disease characterized by continuous and diffuse inflammatory changes in the colonic mucosa, requires novel treatment method. Photodynamic therapy (PDT), as a promising physico-chemical treatment method, were used to treat UC rats’ model with novel photosensitizer LD₄ in this paper, the treatment effect and mechanism was investigated. LD₄-PDT could improve the survival rate of 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced UC model rats, decrease expression of interleukin (IL)-6, IL-1, tumor necrosis factor (TNF)-α, malondialdehyde (MDA), myeloperoxidase (MPO) and increase the expression of glutathione (GSH) and superoxide oxidase (SOD), while protecting the integrity of the intestinal epithelium. LD₄-PDT treatment could rebuild the intestinal microflora composition and reprogram the colonic protein profiles in TNBS-induced rats to almost the normal state. Proteomics analysis based upon TNBS-induced UC model rats revealed that Amine oxidase copper-containing 1 (AOC₁) was a potential target of LD₄-PDT. Novel photosensitizer agent LD₄-PDT represents an efficient treatment method for UC, and AOC₁ may be a promising target.

The Exopolysaccharide Produced by Lactobacillus paracasei IJH-SONE68 Prevents and Ameliorates Inflammatory Responses in DSS-Induced Ulcerative Colitis

Inflammatory bowel disease (IBD) is an autoimmune disease characterized by chronic inflammation of the gastrointestinal tract. IBD includes Crohn’s disease (CD) and ulcerative colitis (UC). CD can occur in any part of the gastrointestinal tract, whereas UC mainly occurs in the colon and rectum. We previously demonstrated that a novel exopolysaccharide (EPS) produced by a plant-derived bacterium, Lactobacillus paracasei IJH-SONE68, prevents and improves the inflammation in contact dermatitis model mice via oral administration. To evaluate the preventive effect of the EPS against other inflammatory diseases, in the present study, we employed dextran sulfate sodium (DSS)-induced UC model mice. The stool consistency, hematochezia, and colonic atrophy of the mice were improved by the orally administered EPS. We also evaluated the cytokine transcription. Overexpression of the mouse macrophage inflammatory protein 2 mRNA in the colon as a functional homolog of human interleukin-8 was decreased by the orally administered EPS. However, the expression of interleukin-10, which is known as an anti-inflammatory cytokine, was stimulated in the EPS-administrated group. Based on these results, we conclude that the IJH-SONE68-derived EPS is a promising lead material for the development of drugs useful in treating inflammatory diseases such as UC.

Patient Preference and Adherence to Aminosalicylates for the Treatment of Ulcerative Colitis

Ulcerative colitis (UC) is a chronic inflammatory disorder that requires sustained treatment for optimal outcomes. The 5-aminosalicylate (5-ASA) class of medications are first-line for the treatment of mild-to-moderate UC but suffer from suboptimal adherence rates in real-world settings. This review summarizes the literature on adherence and patient preference to 5-ASA in patients with UC. We begin by highlighting key studies that measure real-world adherence rates, as well as some of the pitfalls associated with certain techniques. We examine the data on the consequences of non-adherence, which range from decreased quality of life and higher risk of colorectal cancer at the individual level to increased costs to the overall healthcare system. We then turn to the reasons and risk factors for non-adherence and summarize the current understanding of the barriers towards adherence. Afterwards, we describe the research on patient preferences between 5-ASA formulations and dosing regimen. Finally, we summarize the evidence regarding interventions to improve 5-ASA adherence. While adherence remains a challenge in practice, understanding the current state of the field can better inform future efforts towards increasing adherence, and thus clinical outcomes, in UC.

[Efficacy and Safety of Fecal Microbiota Transplantation and Prospect of Microbe-based Therapies for Inflammatory Bowel Disease]

The use of 5-ASA, immunomodulators, biologics, and small molecule drugs are the main treatment for inflammatory bowel disease (IBD), however, fecal microbiota transplantation (FMT) is also drawing attention as a treatment to improve intestinal dysbiosis by transplantaing normal human stool into patients with IBD. FMT demonstrates relatively good effects in inducing clinical remission in IBD, but unlike Clostridium difficile infection, multiple FMT can enhance the clinical effect. There are no reports of the long-term effectiveness and safety of FMT conducted in IBD yet, therefore, well-designed, prospective studies will be needed. Gut microbiota can affect inflammatory response, intestinal barrier function, and host metabolism, so microbe-based therapies are likely to be a new treatment option for IBD. The deeper the understanding of microbe products or effectors, the more likely it is to provide personalized therapy in IBD.

Construction of Chitosan/Alginate Nano-Drug Delivery System for Improving Dextran Sodium Sulfate-Induced Colitis in Mice

(1) Background: In the treatment of ulcerative colitis (UC), accurate delivery and release of anti-inflammatory drugs to the site of inflammation can reduce systemic side effects. (2) Methods: We took advantage of this goal to prepare resveratrol-loaded PLGA nanoparticles (RES-PCAC-NPs) by emulsification solvent volatilization. After layer-by-layer self-assembly technology, we deposited chitosan and alginate to form a three-layer polyelectrolyte film. (3) Results: It can transport nanoparticles through the gastric environment to target inflammation sites and slowly release drugs at a specific pH. The resulting RES-PCAC-NPs have an ideal average diameter (~255 nm), a narrow particle size distribution and a positively charged surface charge (~13.5 mV). The Fourier transform infrared spectroscopy showed that resveratrol was successfully encapsulated into PCAC nanoparticles, and the encapsulation efficiency reached 87.26%. In addition, fluorescence imaging showed that RES-PCAC-NPs with positive charges on the surface can effectively target and accumulate in the inflammation site while continuing to penetrate downward to promote mucosal healing. Importantly, oral RES-PCAC-NPs treatment in DSS-induced mice was superior to other results in significantly improved inflammatory markers of UC. (4) Conclusions: Our results strongly prove that RES-PCAC-NPs can target the inflamed colon for maximum efficacy, and this oral pharmaceutical formulation can represent a promising formulation in the treatment of UC.

Factors associated with the persistence of oral 5-aminosalicylic acid monotherapy in ulcerative colitis: a nationwide Norwegian cohort study

BACKGROUND

Oral 5-aminosalicylic acid (5-ASA) is the mainstay treatment of ulcerative colitis (UC) and therapy with oral 5-ASA is associated with beneficial outcomes. We have examined factors associated with the persistence of oral 5-ASA treatment in a national cohort of UC patients.

METHODS

Patients with newly diagnosed UC from 2010 to 2014 using oral 5-ASA monotherapy were identified by combining data from the Norwegian Patient Registry and the Norwegian Prescription Database. The median follow-up time was 1029 days. Drug persistence was defined as duration of oral 5-ASA preparation as monotherapy. Non-persistence of a oral 5-ASA preparation as monotherapy was defined as stopping oral 5-ASA, initiation of any further anti-inflammatory treatment including a course of glucocorticoids and a change to another oral 5-ASA preparation. Drug persistence was analyzed using the Kaplan-Meier method and influence of covariates on drug persistence was analyzed with the Cox proportional hazard model.

RESULTS

A total of 3421 patients were identified. The overall median 5-ASA drug persistence was 179 days. In univariate analyses, persistence was associated with preparation type and high-dose treatment, while oral glucocorticoid use or hospitalization around the start of oral 5-ASA were associated with shorter 5-ASA persistence. In multivariate analyses, oral glucocorticoids [HR 1.67 (1.54-1.80), p < 0.005] and hospitalization around start of 5-ASA [HR 1.23 (1.14-1.34), p < 0.005] were associated with non-persistence, whereas high dose (⩾3 g/day) 5-ASA was associated with longer persistence [HR 0.68 (0.65-0.71), p < 0.005].

CONCLUSION

High-dose treatment with oral 5-ASA was associated with longer persistence of oral 5-ASA monotherapy, whereas the presence of factors indicating more severe disease around initiation of 5-ASA monotherapy was associated with a shorter persistence.

5-Aminolevulinic Acid as a Novel Therapeutic for Inflammatory Bowel Disease

5-Aminolevulinic acid (5-ALA) is a naturally occurring nonprotein amino acid licensed as an optical imaging agent for the treatment of gliomas. In recent years, 5-ALA has been shown to possess anti-inflammatory and immunoregulatory properties through upregulation of heme oxygenase-1 via enhancement of porphyrin, indicating that it may be beneficial for the treatment of inflammatory conditions. This study systematically examines 5-ALA for use in inflammatory bowel disease (IBD). Firstly, the ex vivo colonic stability and permeability of 5-ALA was assessed using human and mouse fluid and tissue. Secondly, the in vivo efficacy of 5-ALA, in the presence of sodium ferrous citrate, was investigated via the oral and intracolonic route in an acute DSS colitis mouse model of IBD. Results showed that 5-ALA was stable in mouse and human colon fluid, as well as in colon tissue. 5-ALA showed more tissue restricted pharmacokinetics when exposed to human colonic tissue. In vivo dosing demonstrated significantly improved colonic inflammation, increased local heme oxygenase-1 levels, and decreased concentrations of proinflammatory cytokines TNF-α, IL-6, and IL-1β in both plasma and colonic tissue. These effects were superior to that measured concurrently with established anti-inflammatory treatments, ciclosporin and 5-aminosalicylic acid (mesalazine). As such, 5-ALA represents a promising addition to the IBD armamentarium, with potential for targeted colonic delivery.