Pharmacotherapy of ulcerative colitis - current status and emerging trends

Impact of twice-daily budesonide foam administration on early clinical response and endoscopic remission in patients with ulcerative colitis: a post hoc analysis

BACKGROUND AND AIM

Early treatment response of ulcerative colitis (UC) symptom resolution is desirable. This post hoc analysis evaluated efficacy outcomes, including endoscopic remission, by responder status and the influence of once-daily (QD) versus twice-daily (BID) budesonide foam dosing in patients with UC.

METHODS

Data were pooled from phase 2 and phase 3 clinical trials of budesonide rectal foam QD or BID or placebo for up to 12 weeks. Outcomes were evaluated by treatment and budesonide administration regimen and by responder group: early (rectal bleeding subscore [RBS] 0 from Week 2 through Week 6), delayed (RBS 0 at Week 6), and nonresponder (RBS > 0 at Week 6).

RESULTS

The main analysis set included 55 (QD) and 120 (BID) budesonide-treated patients and 116 placebo-treated patients. At Week 6, the trend in early response rate was significant among treatment groups (BID, 45.3%; QD, 32.1%; placebo, 12.8%; P < 0.0001). Among BID recipients, trends for complete endoscopic remission rate (Mayo endoscopic score [MES] = 0) and endoscopic remission rate (MES = 0 or 1) were significant among responder status groups (early responder, 67.4% and 95.4%, respectively; delayed responder, 48.1% and 85.2%; nonresponder, 24.0% and 64.0%; P < 0.001 for both). Regardless of the administration regimen, most early responders achieved endoscopic remission at Week 6. Among responder status groups, early responders' cumulative non-relapse period was greatest (P = 0.07).

CONCLUSION

A BID budesonide administration regimen is preferred to increase the probability of early response and, following endoscopic remission, a better prognosis after stopping treatment.

Exploring the ameliorative potential of Bacopa monnieri in acetic acid induced ulcerative colitis in mice

The aim of the present study was to evaluate the role of Bacopa monnieri in acetic-acid-induced ulcerative colitis in mice. Acetic acid (3%v/v, in 0.9% saline) was infused intrarectally to induce ulceration in mice. Administration of acetic acid resulted in severe inflammation of the colon along with an increase in the myeloperoxidase (MPO) activity assessed on 7th day. Treatment with Bacopa monnieri extract (20 mg/kg and 40 mg/kg, p.o) and saponin-rich fraction (5 mg/kg and 10 mg/kg; p.o) for 7 days i.e. 2 days before and 5 days after acetic acid infusion, significantly attenuated the colonic inflammation in a dose-dependent manner. Furthermore, it also reduced the MPO levels and the disease activity score as compared to the control group. It may be concluded that Bacopa monnieri has the potential for ameliorating acetic-acid-induced colitis and its saponin-rich fraction may be responsible for this effect.

Application of Drug Repurposing Approach for Therapeutic Intervention of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), represented by Crohn's disease (CD) and ulcerative colitis (UC), is a chronic inflammatory disorder of the gastrointestinal tract (GIT) characterized by chronic relapsing intestinal inflammation, abdominal pain, cramping, loss of appetite, fatigue, diarrhoea, and weight loss. Although the etiology of IBD remains unclear, it is believed to be an interaction between genes, and environmental factors, such as an imbalance of the intestinal microbiota, changing food habits, an ultra-hygiene environment, and an inappropriate immune system. The development of novel effective therapies is stymied by a lack of understanding of the aetiology of IBD. The current therapy involves the use of aminosalicylates, immunosuppressants, and corticosteroids that can effectively manage symptoms, induce and sustain remission, prevent complications, modify the course of the disease, provide diverse treatment options, showcase advancements in biologic therapies, and enhance the overall quality of life. However, the efficacy of current therapy is overshadowed by a plethora of adverse effects, such as loss of weight, mood swings, skin issues, loss of bone density, higher vulnerability to infections, and elevated blood pressure. Biologicals, like anti-tumour necrosis factor agents, can stimulate an autoimmune response in certain individuals that may diminish the effectiveness of the medication over time, necessitating a switch to alternative treatments. The response of IBD patients to current drug therapy is quite varied, which can lead to disease flares that underlines the urgent need to explore alternative treatment option to address the unmet need of developing new treatment strategies for IBD with high efficacy and fewer adverse effects. Drug repurposing is a novel strategy where existing drugs that have already been validated safe in patients for the management of certain diseases are redeployed to treat other, unindicated diseases. The present narrative review focuses on potential drug candidates that could be repurposed for the management of IBD using on-target and off-target strategies. It covers their preclinical, clinical assessment, mechanism of action, and safety profiles, and forecasts their appropriateness in the management of IBD. The review presents useful insights into the most promising candidates for repurposing, like anti-inflammatory and anti-apoptotic troxerutin, which has been found to improve the DSS-induced colitis in rats, an antiosteoarthritic drug diacetylrhein that has been found to have remarkable ameliorating effects on DSS-induced colitis via anti-oxidant and anti- inflammatory properties and by influencing both apoptosis and pyroptosis. Topiramate, an antiepileptic and anticonvulsant drug, has remarkably decreased overall pathophysiological and histopathological events in the experimental model of IBD in rodents by its cytokine inhibitory action.

Topical phenytoin administration accelerates the healing of acetic acid-induced colitis in rats: evaluation of transforming growth factor-beta, platelet-derived growth factor, and vascular endothelial growth factor

Ulcerative colitis (UC), limited to the colon's innermost lining, has become a global health problem. Immunomodulatory and monoclonal antibodies are used to treat UC despite their side effects and limitations. Phenytoin is used to heal wounds owing to its effects on growth factors, collagen, and extracellular matrix synthesis. This study aimed to evaluate the effect of topical phenytoin administration in UC. Phenytoin was administered in two doses during the treatment. Eighty male Wistar rats (230-280 g) were divided randomly into ten groups of sham, control, hydrocortisone, phenytoin 1%, and 3% groups in 6- or 12-day treatment protocols. The UC model was induced by the administration of acetic acid 4% into the colon. Animals were killed on the 7th and 13th postoperative days. The main outcome measures included body weight loss, microscopic score, and ulcer index measured using specific criteria. Growth factors were measured by western blotting. Results illustrated that body weight loss was reversed in the treatment groups. Ulcer index had decreased on 6- and 12-day treatment protocols. Microscopic scores in 6-day enema treatment significantly decreased compared to the control groups. Transforming growth factor-beta (TGFβ) significantly increased in a time-dependent manner and platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) significantly increased in a time- and dose-dependent manner in phenytoin 1% and 3% in the 6- and 12-day protocols. Phenytoin dose- and time-dependently reversed weight loss. In addition, histopathological parameters included microscopic scores, and the ulcer index was decreased through the induction of growth factors TGFβ, PDGF, and VEGF and consequently accelerated ulcer healing.

Gut Microbiota-Mediated Transformation of Coptisine Into a Novel Metabolite 8-Oxocoptisine: Insight Into Its Superior Anti-Colitis Effect

Coptisine (COP) is a bioactive isoquinoline alkaloid derived from Coptis Chinemsis Franch, which is traditionally applied for the management of colitis. However, the blood concentration of COP was extremely low, and its gut microbiota-mediated metabolites were thought to contribute to its prominent bioactivities. To comparatively elucidate the protective effect and underlying mechanism of COP and its novel gut microbiota metabolite (8-oxocoptisine, OCOP) against colitis, we used dextran sulfate sodium (DSS) to induce colitis in mice. Clinical symptoms, microscopic alternation, immune-inflammatory parameters for colitis were estimated. The results indicated that OCOP dramatically ameliorated disease activity index (DAI), the shortening of colon length and colonic histopathological deteriorations. OCOP treatment also suppressed the mRNA expression and release of inflammatory mediators (TGF-β, TNF-α, IL-6, IL-18, IL-1β and IFN-γ) and elevated the transcriptional and translational levels of anti-inflammatory cytokine (IL-10) as well as the mRNA expression levels of adhesion molecules (ICAM-1 and VCAM-1). Besides, the activation of NF-κB pathway and NLRP3 inflammasome was markedly inhibited by OCOP. Furthermore, OCOP displayed superior anti-colitis effect to COP, and was similar to MSZ with much smaller dosage. Taken together, the protective effect of OCOP against DSS-induced colitis might be intimately related to inhibition of NF-κB pathway and NLRP3 inflammasome. And the findings indicated that OCOP might have greater potential than COP to be further exploited as a promising candidate in the treatment of colitis.

Effect of roxithromycin on contractile activity of gastrointestinal smooth muscles in colitic rats

OBJECTIVES

Roxithromycin, a macrolide antibiotic, has been shown to ameliorate acetic acid induced colitis in rats by suppressing inflammation and oxidative stress. The aim of this study was to evaluate the effect of roxithromycin on small intestinal transit and cholinergic responsiveness of the colonic smooth muscles of colitic rats.

METHODS

Colitis was induced in rats by acetic acid and the small intestinal transit was determined by measuring the distance traversed by charcoal meal from the gastro-duodenal junction in 1 h. The test drug roxithromycin, reference drug mesalazine and anti-inflammatory drug diclofenac were administered orally before inducing colitis and their effect on intestinal transit was compared with colitic control group. The effect on cholinergic responsiveness of colonic smooth muscles was evaluated in vitro by plotting a dose-response curve using different concentrations of acetylcholine. The concentration producing 50% of maximal response (EC₅₀) was calculated for all the treatment groups.

RESULTS

The small intestinal transit was enhanced in colitic rats as compared to normal rats (86.00 ± 1.36 vs. 57.00 ± 1.34 cm; p<0.001). Like mesalazine, roxithromycin normalized intestinal transit while diclofenac was ineffective. The results of in vitro experiment show that colitis increased cholinergic responsiveness of the colonic smooth muscles that was not affected by roxithromycin and mesalazine while diclofenac significantly decreased it.

CONCLUSIONS

This study shows that like mesalazine, roxithromycin affords protection in colitis mainly by normalizing propulsive movement of the small intestine than by affecting cholinergic responsiveness of the colonic smooth muscles.

Integrative transcriptomic and metabonomic profiling analyses reveal the molecular mechanism of Chinese traditional medicine huankuile suspension on TNBS-induced ulcerative colitis

This study aimed to investigate the therapeutic mechanism of Huankuile suspension (HKL), a typical traditional Chinese medicine, on ulcerative colitis (UC) in a rat model. UC model was established by 2,4,6-trinitrobenzene sulfonic acid (TNBS) enema. Then, the rats were randomly divided into three groups: water treated group, HKL treated group and 5- amino salicylic acid (5-ASA) treated group. After 7 days treatment, the histological score in the HKL treated group was comparable with those in the control group. qRT-PCR and western blot demonstrated that HKL could significantly decreased pro-inflammatory cytokines, including TNF-α, IL-1β and IL-6, while having less effect on anti-inflammatory cytokines, including IL-4 and IL-10. Transcriptomic analysis identified 670 differentially expressed genes (DEGs) between HKL treated UC rats and water treated UC rats. These DEGs were mostly related with immune response. Besides, metabonomic profile revealed 136 differential metabolites which were significantly enriched in “pyrimidine metabolism”, “glutathione metabolism”, “purine metabolism” and “citrate cycle”. Finally, integrated analysis revealed that metabonomic pathways including “steroid hormone biosynthesis”, “pyrimidine metabolism”, “purine metabolism”, and “glutathione metabolism” were altered by HKL at both transcriptomic and metabonomic levels. HKL could inhibit inflammation and regulate bile metabolism, pyrimidine metabolism, purine metabolism, glutathione metabolism and citrate cycle.

Inflammatory Bowel Disease - Non-biological treatment

Nowadays, non-biological treatments remain valuable approaches among the therapeutic armamentarium of inflammatory bowel disease (IBD). Mesalamine is the core treatment of mild‑to‑moderate ulcerative colitis (UC) and corticosteroids are crucial for the induction of remission of moderate‑to‑severe flares in both UC and Crohn's disease (CD). Even approaches as cyclosporine, tacrolimus, azathioprine, methotrexate, and surgery still have a nuclear position as strategies to induce and/or maintain remission in IBD. Due to their particularities and to the accumulated evidence, each of these strategies conquered peculiar roles in the overall IBD strategy, all of them contributing to better outcomes. This review emphasizes the particular roles that non-biological treatments gained over time: recent mesalamine formulations to increase adhesion rates, higher doses of 5-ASA for high-risk patients, MMX technology to improve drug release and attain higher bowel concentrations, cyclosporine as a bridge to vedolizumab, tacrolimus as a potential alternative to thiopurines or infliximab, azathioprine in combination therapy with infliximab and dubious in monotherapy, and surgery as a mean to a "better end".

Ulcerative Colitis: Disease Burden, Impact on Daily Life, and Reluctance to Consult Medical Professionals: Results from a Japanese Internet Survey

Background and Aim

The prevalence of ulcerative colitis has increased in Asian populations in recent years. This Japanese internet survey investigated the symptoms, impact, and treatment of ulcerative colitis, and communication between patients and medical professionals.

Methods

This was a non-interventional analysis of responses from participants with ulcerative colitis who had regularly visited medical providers for their disease in the past year.

Results

In 501 evaluable participants, the mean age was 39.8 years and mean disease duration was 7.6 years. Ulcerative colitis had a "significant impact" on daily life in 43.5% of participants who experienced bowel urgency and 48.6% who experienced bowel incontinence. Although the prevalence of bowel urgency and bowel incontinence was associated with higher stool frequency and rectal bleeding scores (p value for trend <0.0001), they still existed even in patients without frequent stools or rectal bleeding. Around 30% of participants hesitated to discuss symptoms such as bowel incontinence with a medical professional. Approximately three-quarters preferred to use websites for medical information. Most participants (78.0%) had used topical treatments. However, 25.7% were hesitant to use such treatments due to concerns about discomfort (48.1%) and administration difficulty (47.3%).

Conclusions

Ulcerative colitis significantly affects daily life, largely due to symptoms such as bowel urgency and bowel incontinence. Despite desiring to improve bowel incontinence, patients are embarrassed to consult physicians or nurses. Therefore, medical professionals should make an active effort to draw out patients' individual concerns, including symptoms that patients may not initially feel able to talk about openly.

The Possible Anti-Inflammatory Effect of Dehydrocostus Lactone on DSS-Induced Colitis in Mice

Background

Dehydrocostus lactone (DL), one of the main active constituents in Aucklandia lappa Decne. (Muxiang), reported to have anti-inflammatory, antiulcer, and immunomodulatory properties. However, the effect of DL on ulcerative colitis (UC) has not been reported. To analyze the anti-inflammatory potential role of DL in UC, we provide a mechanism for the pharmacological action of DL.

Methods

The experimental model of UC was induced by using oral administration of 2% dextran sulfate sodium (DSS) with drinking water in BALB/c mice. Mesalazine (Mes, 0.52 g/kg/d), DL-high doses (DL-H, 20 mg/kg/d), DL-middle doses (DL-M, 15 mg/kg/d), DL-low doses (DL-L, 10 mg/kg/d) were gavaged once a day from day 4 to day 17. Disease activity index (DAI) was calculated daily. On day 18, mice were rapidly dissected and the colorectal tissues were used to detect the levels of UC-related inflammatory cytokines (TNF-α, IL-1β, MCP-1, MPO, SOD, IL-6, IL-17, and IL-23), IL-6/STAT3 inflammatory signaling pathway (iNOS, COX2, IL-6, GP130, L-17, and IL-23), and colorectal mucosal barrier-related regulatory factors (MUC2, XBP1s, and α, IL-1

Results

DL reduced the colorectal inflammation histological assessment, decreased UC-related inflammatory cytokines (TNF-α, IL-1β, MCP-1, MPO, SOD, IL-6, IL-17, and IL-23), IL-6/STAT3 inflammatory signaling pathway (iNOS, COX2, IL-6, GP130, L-17, and IL-23), and colorectal mucosal barrier-related regulatory factors (MUC2, XBP1s, and α, IL-1

Conclusions

DL possessed the potential of anti-inflammatory effect to treated colitis. The protective mechanism of DL may involve in reducing inflammation and improving colorectal barrier function via downregulating the IL-6/STAT3 signaling.

Exploring the therapeutic potential of sodium benzoate in acetic acid-induced ulcerative colitis in rats

Background Ulcerative colitis is a chronic mucosal inflammation of the large intestine mainly affecting the colon and rectum. The lack of effective and safe therapeutic agents led to the identification of new therapeutic agents to effectively manage the symptoms and complications of ulcerative colitis. The present study aimed to evaluate the protective effect of sodium benzoate in acetic acid-induced ulcerative colitis in rats. Methods Infusion of 3% acetic acid in the colon through the rectum was done to construct a rat model of ulcerative colitis. After 5 days of infusion, macroscopic, biochemical, and histopathological examinations and disease activity scoring of the colon were done to assess colonic damage. Results Acetic acid infusion resulted in severe inflammation in the colon assessed macroscopically and histopathologically. Moreover, it also led to increase in myeloperoxidase (MPO) and reduction in glutathione (GSH) levels. In the present study, repeated administration of sodium benzoate (400 and 800 mg/kg i.p.) and sulfasalazine (500 mg/kg orally) for 7 days, i.e. 2 days before and continued for 5 days after acetic acid infusion, significantly attenuated macroscopic damage and disease activity score as compared to disease control. Further, it also significantly reduced the levels of MPO and enhanced colonic levels of reduced GSH. However, the lower dose of sodium benzoate (200 mg/kg) did not show sufficient protective effect in acetic acid-induced ulcerative colitis. Further, sodium benzoate per se did not show any effect in normal rats. Conclusions The observed protective effect of sodium benzoate may be due to its antioxidant and anti-inflammatory activities in an ulcerative colitis model.

Advances in research of tacrolimus for treatment of inflammatory bowel disease

Traditional drugs for inflammatory bowel disease (IBD) include aminosalicylic acid preparations, glucocorticoids, and immunosuppressive agents such as thiopurine and cyclosporine. In recent ten years, the application of anti-tumor necrosis factor (anti-TNF) drugs has greatly improved the clinical remission of patients with IBD, but there are still some problems, such as no response, intolerance, and recurrence after withdrawal. In recent years, tacrolimus, as a new powerful immunosuppressive agent, has been used as a second-line therapeutic drug for IBD. At present, the tacrolimus induced short-term remission effect in IBD is relatively obvious, and it has been gradually used for treatment of IBD refractory to traditional drugs or anti-TNF drugs. A few studies have found that tacrolimus can be used safely for a long time under proper monitoring. However, there is little evidence of long-term efficacy and safety. In this paper, we review the latest advances in the treatment of IBD with tacrolimus and make a comparison with anti-TNF drugs.