Toxic effects of nonsteroidal antiinflammatory drugs on the small bowel, colon, and rectum

Colonic Diaphragmatic Disease: The Concerning Dark Depths of NSAIDs

Non-steroidal anti-inflammatory drugs (NSAIDs), widely used for their therapeutic benefits, are associated with significant gastrointestinal complications, including the rare occurrence of colonic diaphragm disease (CDD). Characterized by diaphragm-like fibrotic strictures that narrow the intestinal lumen, CDD often leads to symptoms such as chronic anemia, bowel obstruction, and gastrointestinal bleeding. This report discusses a case of NSAID-induced CDD in a 58-year-old male with a history of prolonged NSAID use for osteoarthritis. The patient's clinical course was marked by progressive fatigue, melena, and intestinal obstruction, necessitating multiple hospitalizations and interventions. Our findings underscore the frequent association of CDD with prolonged NSAID use, particularly enteric-coated formulations, and the predominance of lesions in the right colon. Furthermore, we conducted a comprehensive review of the literature, summarizing 53 reported cases of NSAID-induced colonic diaphragm disease. This review highlights the common clinical manifestations, diagnostic challenges, and therapeutic strategies for this rare condition. Despite medical management and endoscopic interventions, the patient required subtotal colectomy due to recurrent strictures and complications. This case underscores the diagnostic challenges posed by CDD, particularly its overlap with inflammatory bowel disease. Surgical exploration and histological evaluation were essential for diagnosing CDD and guiding appropriate management. This case highlights the importance of recognizing NSAID-induced enteropathy in the differential diagnosis of patients with unexplained gastrointestinal symptoms, emphasizing the need for a thorough drug history and tailored therapeutic strategies. Advanced surgical techniques and novel treatments continue to improve the management of gastrointestinal complications, bettering patient outcomes, and quality of life.

Recent progress in adverse events of carboxylic acid non-steroidal anti-inflammatory drugs (CBA-NSAIDs) and their association with the metabolism: the consequences on mitochondrial dysfunction and oxidative stress, and prevention with natural plant extracts

INTRODUCTION

Carboxylic acid non-steroidal anti-inflammatory drugs (CBA-NSAIDs) are extensively used worldwide due to their antipyretic, analgesic, and anti-inflammatory effects. CBA-NSAIDs have reasonable margin of safety at therapeutic doses, and in the current climate, do not possess addiction potential like opioid drugs. Studies have revealed that various adverse events of CBA-NSAIDs are related mitochondrial dysfunction and oxidative stress.

AREAS COVERED

This review article summarizes adverse events induced by CBA-NSAIDs, mechanisms of mitochondrial damage, oxidative stress, and metabolic interactions. Meanwhile, this review discusses the treatment and prevention of CBA-NSAIDs damage by natural plant extracts based on antioxidant effects.

EXPERT OPINION

CBA-NSAIDs can induce reactive oxygen species (ROS) production, mediate DNA, protein and lipid damage, lead to imbalance of cell antioxidant status, change of mitochondrial membrane potential, activate oxidative stress signal pathway, thus leading to oxidative stress and cell damage. Adverse events caused by CBA-NSAIDs often exhibit dose and time dependence. In order to avoid adverse events caused by CBA-NSAIDs, it is necessary to provide detailed patient consultation and eliminate influencing factors. Moreover, constructive research studies on the organ-specific toxicity and mechanism of natural plant extracts in preventing and treating metabolic abnormalities of CBA-NSAIDs, will provide important value for warning and guidance for use of CBA-NSAIDs.

Occurrence, toxicity, impact and removal of selected non-steroidal anti-inflammatory drugs (NSAIDs): A review

Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most frequently used pharmaceuticals for human therapy, pet therapeutics, and veterinary feeds, enabling them to enter into water sources such as wastewater, soil and sediment, and seawater. The control of NSAIDs has led to the advent of the novel materials for treatment techniques. Herein, we review the occurrence, impact and toxicity of NSAIDs against aquatic microorganisms, plants and humans. Typical NSAIDs, e.g., ibuprofen, ketoprofen, diclofenac, naproxen and aspirin were detected at high concentrations in wastewater up to 2,747,000 ng L-1. NSAIDs in water could cause genotoxicity, endocrine disruption, locomotive disorders, body deformations, organs damage, and photosynthetic corruption. Considering treatment methods, among adsorbents for removal of NSAIDs from water, metal-organic frameworks (10.7-638 mg g-1) and advanced porous carbons (7.4-400 mg g-1) were the most robust. Therefore, these carbon-based adsorbents showed promise in efficiency for the treatment of NSAIDs.

Research progress of non-steroidal anti-inflammatory drug-induced small intestinal injury

Non-steroidal anti-inflammatory drugs (NSAIDs) are used widely around the world because of their anti-inflammatory, analgesic, and antiplatelet activity. However, long-term application of NSAIDs can lead to complications. Previously, the clinical attention was dedicated to the NSAID-induced upper gastrointestinal complications. Recently, the detection rate of small intestinal damage related to NSAIDs has increased due to the wide use of endoscopes such as capsule endoscopy and double-balloon colonoscopy. Although the majority of patients have no significant symptoms, there are still a small percentage of patients who develop obvious symptoms or complicated ulcers that require therapeutic intervention. Despite significant advances in our understanding of NSAIDs, the treatment modality and regimen for NSAID-induced small intestinal damage have remained relatively unclear. This article will provide a comprehensive overview of NSAID-induced small intestinal damage with regard to the epidemiology, clinical manifestations, diagnosis, risk factors, pathogenesis, and treatment, in order to provide informative evidence for clinical practice.

Medical treatment of pouchitis: a guide for the clinician

Pouchitis is the most common complication in patients who have undergone restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA). Up to 81% of IPAA patients experience pouchitis, with 40% of patients presenting within the first year of surgery. Common risk factors include genetic mutations, extensive colitis, rheumatologic disorders, and primary sclerosing cholangitis. Currently, there are no medications with approved indications for pouchitis. As such, the conventional treatment of pouchitis is entirely off-label. This paper is intended to be a practical and up-to-date review of available therapies used for the management of pouchitis. The mainstay of treatment for acute pouchitis remains antibiotics, but newer therapeutics have also shown promise in the treatment of chronic pouchitis. Common lifestyle considerations that may play a role in pouchitis are also reviewed.

PLAIN LANGUAGE SUMMARY

Medical treatment of pouchitis: a guide for the clinician The ileal pouch-anal anastomosis ("pouch") is the most common way patients who require surgery to remove their colon are able to avoid a permanent ileostomy ("ostomy"). This pouch, created from the small intestines, serves as a reservoir to hold stool. The most common complication after pouch surgery is pouchitis. Pouchitis symptoms include more frequent bowel movements, urgency to defecate, blood in the stool, incontinence, and abdominal pain. This paper is intended to be a practical review of available therapies including medications and lifestyle changes that can be considered for the management of acute pouchitis, chronic pouchitis, and cuffitis.

In vitro Anti-inflammatory Effects of Satureja Kkhuzestanica Essential Oil Compared to Carvacrol

Introduction: Satureja khozestanica grows mainly in the southwest part of Iran as a native plant. This edible herb contains various compounds including the S. Khuzestanica essential oil (SKEO) and monoterpene known as Carvacrol. Previous studies have shown the anti-inflammatory effects of S. Khuzestanica without mentioning the exact mechanism of its function. Given that prostaglandin synthesis, which is one of the main mediators of inflammation, is regulated by the cyclooxygenase-2 (COX2) gene, the present study investigated the effects of SKEO and Carvacrol on the expression of the COX2 gene in the stimulated-J774A.1 macrophage cell line. Methods: To this end, fresh aerial parts of the plant were processed to prepare SKEO. Then, different doses of SKEO and Carvacrol (i.e., 0.004%, 0.008%, and 0.016% v/v) were used to treat with the lipopolysaccharides (LPS)-stimulated cell line for eight hours. After RNA extraction, the real-time polymerase chain reaction technique was applied for gene expression analysis. Results: In the LPS-stimulated J774A.1 macrophage cell line, COX2 gene expression reduced significantly in a dose-dependent manner (0.004%, 0.008%, and 0.016%, P = 0.024, P = 0.021, and P = 0.013 v/v of SKEO, respectively) by SKEO, and the effect of Carvacrol was less powerful (0.008% and 0.016%, P = 0.027 and P = 0.038 v/v, respectively) compared to SKEO. Finally, the comparison between SKEO and Carvacrol showed higher significant inhibitory effects of SKEO on COX2 gene expression in comparison with Carvacrol in 0.004% v/v concentration (P = 0.037). Conclusion: In general, SKEO significantly reduced COX2 gene expression, thus it can be suggested that its anti-inflammatory effect may result from the inhibition of the synthesis of this pro-inflammatory gene.

Mud-bath treatment of seronegative spondyloarthritis: experience at the Euganean Thermal Area

Mud-bath therapy (MBT) has been used as a treatment for rheumatic diseases and musculoskeletal complaints in the Euganean Thermal Area (near Padova, Italy) since ancient time. There is no consensus about the use of MBT in patients with inflammatory rheumatic diseases, although experimental studies have suggested a beneficial effect of MBT on chronic articular inflammation. To evaluate the effects of MBT in patients affected by seronegative spondyloarthritis, very common chronic inflammatory rheumatic diseases, randomized controlled trials (RCT) performed in the Euganean Thermal Area have been reviewed. A significant improvement of spondylitis parameters was observed in enteropathic spondylitis, without bowel symptom exacerbation. A long-term amelioration of clinical evaluation indices was found in ankylosing spondylitis. A significant improvement of cutaneous lesions, arthritis activity, and patient's functional ability was observed in psoriatic arthritis. MBT was usually well tolerated and adverse side effects were rarely reported. The review of the RCT suggests that MBT may exert additional beneficial effects in patients with seronegative spondyloarthritis treated with pharmacological therapy.

An Unusual Case of Colon Perforation With Multiple Transmural Ulcers After Use of Polmacoxib and Everolimus in a Metastatic Breast Cancer Patient

Everolimus (Afinitor) is an inhibitor of mammalian target of rapamycin. Polmacoxib (Acelex) is a nonsteroidal anti-inflammatory drug that belongs to the cyclooxygenase-2 (COX-2) inhibitor family and is mainly used for treatment of arthritis. Intestinal perforation has not been reported previously as a complication of everolimus, and perforation of the lower intestinal tract caused by a selective COX-2 inhibitor is extremely rare. We present here a case of colon perforation that occurred after use of polmacoxib in a metastatic breast cancer patient who had been treated with everolimus for the preceding six months.

Drugging cancer metabolism: Expectations vs. reality

As compared to their normal counterparts, neoplastic cells exhibit a variety of metabolic changes that reflect not only genetic and epigenetic defects underlying malignant transformation, but also the nutritional and immunobiological conditions of the tumor microenvironment. Such alterations, including the so-called Warburg effect (an increase in glucose uptake largely feeding anabolic and antioxidant metabolism), have attracted considerable attention as potential targets for the development of novel anticancer therapeutics. However, very few drugs specifically conceived to target bioenergetic cancer metabolism are currently approved by regulatory agencies for use in humans. This reflects the elevated degree of heterogeneity and redundancy in the metabolic circuitries exploited by neoplastic cells from different tumors (even of the same type), as well as the resemblance of such metabolic pathways to those employed by highly proliferating normal cells. Here, we summarize the major metabolic alterations that accompany oncogenesis, the potential of targeting bioenergetic metabolism for cancer therapy, and the obstacles that still prevent the clinical translation of such a promising therapeutic paradigm.

Mouse Model of Mutated in Colorectal Cancer Gene Deletion Reveals Novel Pathways in Inflammation and Cancer

BACKGROUND & AIMS

The early events by which inflammation promotes cancer are still not fully defined. The MCC gene is silenced by promoter methylation in colitis-associated and sporadic colon tumors, but its functional significance in precancerous lesions or polyps is not known. Here, we aimed to determine the impact of Mcc deletion on the cellular pathways and carcinogenesis associated with inflammation in the mouse proximal colon.

METHODS

We generated knockout mice with deletion of Mcc in the colonic/intestinal epithelial cells (Mcc^ΔIEC) or in the whole body (Mcc^Δ/Δ). Drug-induced lesions were analyzed by transcriptome profiling (at 10 weeks) and histopathology (at 20 weeks). Cell-cycle phases and DNA damage proteins were analyzed by flow cytometry and Western blot of hydrogen peroxide-treated mouse embryo fibroblasts.

RESULTS

Transcriptome profiling of the lesions showed a strong response to colon barrier destruction, such as up-regulation of key inflammation and cancer-associated genes as well as 28 interferon γ-induced guanosine triphosphatase genes, including the homologs of Crohn's disease susceptibility gene IRGM. These features were shared by both Mcc-expressing and Mcc-deficient mice and many of the altered gene expression pathways were similar to the mesenchymal colorectal cancer subtype known as consensus molecular subtype 4 (CMS4). However, Mcc deletion was required for increased carcinogenesis in the lesions, with adenocarcinoma in 59% of Mcc^ΔIEC compared with 19% of Mcc-expressing mice (P = .002). This was not accompanied by hyperactivation of β-catenin, but Mcc deletion caused down-regulation of DNA repair genes and a disruption of DNA damage signaling.

CONCLUSIONS

Loss of Mcc may promote cancer through a failure to repair inflammation-induced DNA damage. We provide a comprehensive transcriptome data set of early colorectal lesions and evidence for the in vivo significance of MCC silencing in colorectal cancer.

Balneotherapy in chronic inflammatory rheumatic diseases-a narrative review

Since ancient time, thermal baths and mudpacks have been used as treatments for rheumatic diseases and other musculoskeletal complaints. Despite basic researches suggest an anti-inflammatory effect of spa therapy, there is no consensus about the benefits of balneotherapy in patients with chronic inflammatory rheumatic diseases. The aim of this review is to summarize the currently available information on clinical effects of balneotherapy in these diseases. We did a literature search for articles considering the randomized controlled trials (RCTs) published until today. Although many selected studies do not have an elevated methodological quality, data from these RCTs support a beneficial effect of spa therapy. Balneotherapy highly improves the clinical course of the disease in patients with predominant axial involvement, such as with ankylosing and enteropathic spondylitis; the effects are less favorable in patients with predominant peripheral articular inflammation, such as rheumatoid arthritis. Good results have been observed in patients with psoriatic arthritis, but only few RCTs have been conducted on this disease. Spa therapy appears safe, and adverse events have been reported only in a few patients.

The colon and terminal ileum in patients with ankylosing spondylitis and controls in Bangladesh: a macroscopic and microscopic study

OBJECTIVE

Little is known about gut lesions in AS patients in a developing country, such as Bangladesh.

METHODS

Full colonoscopy, including the terminal ileum, was performed in 60 AS patients and 20 controls, without diarrhoea, to study macroscopic and microscopic lesions.

RESULTS

In the colon, in 60 AS patients 17 macroscopic lesions were found, of which 11 were in the rectum; only one lesion was found in 20 controls. The prevalence of microscopic lesions in the ascending colon, sigmoid colon and rectum was 51, 44 and 50 in patients, respectively, and 13, 9 and 8 in controls. In the terminal ileum, macroscopic and microscopic lesions were seen in 21/56 and 43/56 AS patients, respectively, and in 1/20 and 9/20 controls. In the AS group, macroscopic (38.5 vs 5%, P < 0.01) and microscopic (76.8 vs 45%, P = 0.009) lesions were more frequent than in controls; no IBD was diagnosed. Findings were comparable in the axial AS group (n = 25) and the mainly peripheral group (n = 35). In AS patients, marked eosinophilic infiltration was observed in the ascending colon and sigmoid colon but not in the rectum, and this infiltration was more than in controls. The colonic mucosa in controls was otherwise comparable with western studies. Anaemia was seen in 18/60 cases. No association was found between anaemia or HLA-B27 status and gut lesions.

CONCLUSION

There was an equal percentage of microscopic lesions in the whole gut in AS cases and healthy controls. Previous helminth invasions might have played a role. Lesions differ significantly between AS and controls only in the ileum; therefore, the ileal lesions might be more disease related than the colonic ones.

Complications related to chronic supratherapeutic use of codeine containing compound analgesics in a cohort of patients presenting for codeine withdrawal

INTRODUCTION AND AIMS

This study aimed to compare complications arising due to the supratherapeutic use of paracetamol/codeine or ibuprofen/codeine containing compound analgesics in primary codeine-dependent patients presenting to a drug and alcohol withdrawal service. Data was compared to determine if there was any difference in the number of complications observed between the two groups.

DESIGN AND METHODS

A retrospective case review of patients presenting for primary codeine dependence from 2009 to 2014. Sixty patients (42F, 36 ± 10 years) using ibuprofen/codeine and 46 (26F, 39 ± 10 years) using paracetamol/codeine containing compound analgesics were compared. A P value of <0.05 was considered significant.

RESULTS

Patients consumed similar daily doses of codeine (699 ± 45 vs. 636 ± 50 mg) with those consuming ibuprofen/codeine containing compound analgesics ingesting twice as many tablets daily (median 60 vs. 30 tablets; P < 0.0001). Complications related to supratherapeutic use of codeine containing compound analgesics occurred more commonly in patients taking ibuprofen/codeine (52/60; 87%) versus paracetamol/codeine compound analgesics (30/46; 65%) (P < 0.01). Patients taking ibuprofen/codeine containing compound analgesics were more likely to have gastrointestinal bleeding (P < 0.05), anaemia (P < 0.0001) and renal tubular acidosis (P < 0.05). There were two deaths in the group abusing ibuprofen/codeine compound analgesics.

DISCUSSION AND CONCLUSIONS

In patients with primary codeine dependence, there were more complications related to the supratherapeutic use of ibuprofen/codeine versus paracetamol/codeine containing compound analgesics. The patients in both groups ingested similar total daily codeine amounts. Increased daily tablet intake in the ibuprofen/codeine group could possibly have been linked to lower codeine content per tablet.

Review article: a practical approach to the clinical management of NSAID enteropathy

Co-prescription of acid suppressive therapy, together with advances in small bowel imaging techniques, have shifted the burden of NSAID-related toxicity from gastro-duodenal to more distal small bowel injury. Due to predominantly subclinical disease, NSAID enteropathy remains under-recognised, with an incidence of 53-80% amongst healthy short-term users, and a prevalence of 50-71% following long-term (>3 months) use. Despite their distinct pathogenesis, those at risk of NSAID-related gastro-duodenal and small bowel complications share several risk factors. Clinical complications of NSAID enteropathy such as protein-losing enteropathy, small bowel strictures and diaphragm disease, confer significant morbidity, and are often irreversible. Small bowel prophylaxis has proven of modest efficacy after short-term, high-dose NSAID use in asymptomatic patients. While selective COX-2 inhibitors are associated with fewer gastro-duodenal complications relative to non-selective NSAIDs, their comparative benefit in protecting against small bowel enteropathy remains unclear. Prophylaxis should be considered in those at high risk of small bowel complications, as treatment options for established disease remain limited; however, the optimal agent remains unclear. We propose a clinical algorithm that may help prevent, monitor, investigate, and manage the sequelae of NSAID-induced small bowel toxicity.

The Effect of DA-6034 on Intestinal Permeability in an Indomethacin-Induced Small Intestinal Injury Model

Background/Aims

DA-6034 has anti-inflammatory activities and exhibits cytoprotective effects in acute gastric injury models. However, explanations for the protective effects of DA-6034 on intestinal permeability are limited. This study sought to investigate the effect of DA-6034 on intestinal permeability in an indomethacin-induced small intestinal injury model and its protective effect against small intestinal injury.

Methods

Rats in the treatment group received DA-6034 from days 0 to 2 and indomethacin from days 1 to 2. Rats in the control group received indomethacin from days 1 to 2. On the fourth day, the small intestines were examined to compare the severity of inflammation. Intestinal permeability was evaluated by using fluorescein isothiocyanate-labeled dextran. Western blotting was performed to confirm the association between DA-6034 and the extracellular signal-regulated kinase (ERK) pathway.

Results

The inflammation scores in the treatment group were lower than those in the control group, but the difference was statistically insignificant. Hemorrhagic lesions in the treatment group were broader than those in the control group, but the difference was statistically insignificant. Intestinal permeability was lower in the treatment group than in the control group. DA-6034 enhanced extracellular signal-regulated kinase expression, and intestinal permeability was negatively correlated with ERK expression.

Conclusions

DA-6034 may decrease intestinal permeability in an indomethacin-induced intestinal injury model via the ERK pathway.

Pharmacological Approach for Managing Pain in Irritable Bowel Syndrome: A Review Article

Context

Visceral pain is a leading symptom for patients with irritable bowel syndrome (IBS) that affects 10% - 20 % of the world population. Conventional pharmacological treatments to manage IBS-related visceral pain is unsatisfactory. Recently, medications have emerged to treat IBS patients by targeting the gastrointestinal (GI) tract and peripheral nerves to alleviate visceral pain while avoiding adverse effects on the central nervous system (CNS). Several investigational drugs for IBS also target the periphery with minimal CNS effects.

Evidence of Acquisition

In this paper, reputable internet databases from 1960 - 2016 were searched including Pubmed and ClinicalTrials.org, and 97 original articles analyzed. Search was performed based on the following keywords and combinations: irritable bowel syndrome, clinical trial, pain, visceral pain, narcotics, opioid, chloride channel, neuropathy, primary afferent, intestine, microbiota, gut barrier, inflammation, diarrhea, constipation, serotonin, visceral hypersensitivity, nociceptor, sensitization, hyperalgesia.

Results

Certain conventional pain managing drugs do not effectively improve IBS symptoms, including NSAIDs, acetaminophen, aspirin, and various narcotics. Anxiolytic and antidepressant drugs (Benzodiazepines, TCAs, SSRI and SNRI) can attenuate pain in IBS patients with relevant comorbidities. Clonidine, gabapentin and pregabalin can moderately improve IBS symptoms. Lubiprostone relieves constipation predominant IBS (IBS-C) while loperamide improves diarrhea predominant IBS (IBS-D). Alosetron, granisetron and ondansetron can generally treat pain in IBS-D patients, of which alosetron needs to be used with caution due to cardiovascular toxicity. The optimal drugs for managing pain in IBS-D and IBS-C appear to be eluxadoline and linaclotide, respectively, both of which target peripheral GI tract.

Conclusions

Conventional pain managing drugs are in general not suitable for treating IBS pain. Medications that target the GI tract and peripheral nerves have better therapeutic profiles by limiting adverse CNS effects.

Association between NSAIDs and Clostridium difficile-Associated Diarrhea: A Systematic Review and Meta-Analysis

Objective. Clostridium difficile infection is a leading cause of nosocomial diarrhea in developed countries. Studies evaluating the associations of increased risk of community-acquired CDAD and the use of nonsteroidal anti-inflammatory drugs (NSAIDs) have yielded inconclusive results. We conducted a systematic review and meta-analysis to compare the odds of NSAID exposure in patients with CDAD versus patients without CDAD in both community-based and healthcare-associated settings. Methods. Relevant observational studies indexed in PubMed/MEDLINE and EMBASE up to February 2015 were analyzed and data were extracted from nine studies. Of these, eight studies were included in the meta-analysis. Results. A search of the databases resulted in 987 articles. The nine studies from which data were extracted involved over 39,000 subjects. The pooled odds ratio for history of NSAID use in participants with CDAD compared with controls was 1.41 (95% CI 1.06-1.87; p < 0.01), indicating a significant increased odds of CDAD among patients exposed to NSAIDs. Conclusions. To the best of our knowledge, this is the first study of its nature to demonstrate the association between the use of NSAIDs and increased risk of CDAD. Further studies to evaluate if any specific types of NSAIDs can increase the risk of CDAD are warranted.

The Antiinflammatory Properties of Humic Substances: A Mini Review

Humic substances are effective in the suppression of delayed type hypersensitivity, rat paw oedema, a graft-versus-host reaction and contact hypersensitivity in rats. They reduce the C-reactive protein levels of patients suffering from osteoarthritis of the knee and the wheel and flare reaction of patients suffering from hay fever. They have also been described as cardioprotective and pro-angiogenic. Toxicity studies have indicated that potassium humate is safe in humans up to a daily dosage of 1 g/kg, whereas fulvic acid is safe in humans up to a daily dosage of 1.8 g per adult. The antiinflammatory action of potassium humate can be contributed to the inhibition of the release of inflammatory-related cytokines, an adhesion molecule, oxidants and components of the complement system.

Sulindac reversal of 15-PGDH-mediated resistance to colon tumor chemoprevention with NSAIDs

Non-steroidal anti-inflammatory drugs prevent colorectal cancer by inhibiting cyclooxygenase (COX) enzymes that synthesize tumor-promoting prostaglandins. 15-hydroxyprostaglandin dehydrogenase (15-PGDH) is a tumor suppressor that degrades tumor-promoting prostaglandins. Murine knockout of 15-PGDH increases susceptibility to azoxymethane-induced colon tumors. It also renders these mice resistant to celecoxib, a selective inhibitor of inducible COX-2 during colon neoplasia. Similarly, humans with low colonic 15-PGDH are also resistant to colon adenoma prevention with celecoxib. Here, we used aspirin and sulindac, which inhibit both COX-1 and COX-2, in order to determine if these broader COX inhibitors can prevent colon tumors in 15-PGDH knockout (KO) mice. Unlike celecoxib, sulindac proved highly effective in colon tumor prevention of 15-PGDH KO mice. Significantly, however, aspirin demonstrated no effect on colon tumor incidence in either 15-PGDH wild-type or KO mice, despite a comparable reduction in colonic mucosal Prostaglandin E₂ (PGE₂) levels by both sulindac and aspirin. Notably, colon tumor prevention activity by sulindac was accompanied by a marked induction of lymphoid aggregates and proximal colonic inflammatory mass lesions, a side effect seen to a lesser degree with celecoxib, but not with aspirin. These findings suggest that sulindac may be the most effective agent for colon cancer prevention in humans with low 15-PGDH, but its use may also be associated with inflammatory lesions in the colon.

Optimization of sustained release aceclofenac microspheres using response surface methodology

Polymeric microspheres containing aceclofenac were prepared by single emulsion (oil-in-water) solvent evaporation method using response surface methodology (RSM). Microspheres were prepared by changing formulation variables such as the amount of Eudragit® RS100 and the amount of polyvinyl alcohol (PVA) by statistical experimental design in order to enhance the encapsulation efficiency (E.E.) of the microspheres. The resultant microspheres were evaluated for their size, morphology, E.E., and in vitro drug release. The amount of Eudragit® RS100 and the amount of PVA were found to be significant factors respectively for determining the E.E. of the microspheres. A linear mathematical model equation fitted to the data was used to predict the E.E. in the optimal region. Optimized formulation of microspheres was prepared using optimal process variables setting in order to evaluate the optimization capability of the models generated according to IV-optimal design. The microspheres showed high E.E. (74.14±0.015% to 85.34±0.011%) and suitably sustained drug release (minimum; 40% to 60%; maximum) over a period of 12h. The optimized microspheres formulation showed E.E. of 84.87±0.005 with small error value (1.39). The low magnitudes of error and the significant value of R(2) in the present investigation prove the high prognostic ability of the design. The absence of interactions between drug and polymers was confirmed by Fourier transform infrared (FTIR) spectroscopy. Differential scanning calorimetry (DSC) and X-ray powder diffractometry (XRPD) revealed the dispersion of drug within microspheres formulation. The microspheres were found to be discrete, spherical with smooth surface. The results demonstrate that these microspheres could be promising delivery system to sustain the drug release and improve the E.E. thus prolong drug action and achieve the highest healing effect with minimal gastrointestinal side effects.

Prevalence and risk factors of Clostridium difficile infection in patients hospitalized for flare of inflammatory bowel disease: a retrospective assessment

BACKGROUND

Recent studies have identified a high frequency of Clostridium difficile infections in patients with active inflammatory bowel disease.

AIMS

To retrospectively assess the determinants and results of Clostridium difficile testing upon the admission of patients hospitalized with active inflammatory bowel disease in a tertiary care centre and to determine the predicting factors of Clostridium difficile infections.

METHODS

We reviewed all admissions from January 2008 and December 2010 for inflammatory bowel disease flare-ups. A toxigenic culture and a stool cytotoxicity assay were performed for all patients tested for Clostridium difficile.

RESULTS

Out of 813 consecutive stays, Clostridium difficile diagnostic assays have been performed in 59% of inpatients. The independent predictive factors for the testing were IBD (ulcerative colitis: OR 2.0, 95% CI 1.5-2.9; p<0.0001) and colonic involvement at admission (OR 2.2, 95% CI 1.5-3.1, p<0.0001). Clostridium difficile infection was present in 7.0% of the inpatients who underwent testing. In a multivariate analysis, the only independent predictor was the intake of nonsteroidal anti-inflammatory drugs within the two months before admission (OR 3.8, 95% CI 1.2-12.3; p=0.02).

CONCLUSIONS

Clostridium difficile infection is frequently associated with active inflammatory bowel disease. Our study suggests that a recent intake of nonsteroidal anti-inflammatory drugs is a risk factor for inflammatory bowel disease -associated Clostridium difficile infection.

Tolerability of selective cyclooxygenase 2 inhibitors used for the treatment of rheumatological manifestations of inflammatory bowel disease

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) are used to reduce inflammatory pain and swelling in inflammatory bowel disease (IBD) patients with rheumatological manifestations. While these drugs effectively reduce musculoskeletal pain and stiffness, long-term use is limited by gastrointestinal (GI) adverse effects (AEs) and disease exacerbation. As an alternative to NSAIDs, selective cyclooxygenase 2 (COX-2) inhibitors were developed to improve GI safety and tolerability. COX-2 inhibitors include drugs such as celecoxib, rofecoxib, valdecoxib, etoricoxib, and lumiracoxib. Rofecoxib and valdecoxib have been withdrawn from the market worldwide due to safety concerns (most importantly for cardiovascular adverse events) and lumiracoxib has been withdrawn in many countries due to liver toxicity. However, celecoxib and etoricoxib continue to be available for use in many countries. Several studies have examined whether COX-2 inhibitors can be safely used for the treatment of rheumatological manifestations of IBD with inconsistent results. Some investigators report acceptable safety profiles associated with these drugs while others found that COX-2 inhibitors are associated with high rates of disease exacerbation.

OBJECTIVES

The objective of this systematic review was to evaluate the tolerability and safety of COX-2 inhibitors used for the treatment of rheumatological manifestations of IBD.

SEARCH METHODS

We searched the following databases from inception to 19 September 2013: PubMed, EMBASE, MEDLINE and CENTRAL. The search was not limited by language. Additional trials were identified by manually searching the reference lists of relevant papers and conference proceedings and through correspondence with experts and pharmaceutical companies.

SELECTION CRITERIA

Randomized controlled trials (RCTs) that compared COX-2 inhibitors to placebo were considered for inclusion. Participants were adult patients with IBD presenting with rheumatological manifestations of at least two weeks duration.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial eligibility and extracted data. Methodological quality was assessed using the Cochrane risk of bias tool. The primary outcome measure was the proportion of patients with disease exacerbation as defined by the included studies. Secondary outcomes included GI adverse effects, renal toxicity, cardiovascular and thrombotic events. Data were analysed on an intention-to-treat basis where patients with missing final outcomes were assumed to have had an exacerbation of IBD. We calculated the risk ratio (RR) and corresponding 95% confidence interval (95% CI) for dichotomous outcomes. The overall quality of the evidence was assessed using the GRADE criteria.

MAIN RESULTS

There were no RCTs that assessed the tolerability or safety of the withdrawn COX-2 inhibitors rofecoxib, valdecoxib, or lumiracoxib. Two RCTs (n = 381 IBD patients with rheumatological manifestations) were included in the review. One study (n = 159) compared etoricoxib (60 to 120 mg/day) to placebo in IBD patients with quiescent or active ulcerative colitis or Crohn's disease. The other study (n = 222) compared celecoxib (200 mg twice daily) to placebo in patients with quiescent ulcerative colitis. Both studies were judged to be at low risk of bias. The two included studies were not pooled for meta-analysis due to differences in patient populations and treatment duration. There was no statistically significant difference in exacerbation of IBD between etoricoxib and placebo. After 12 weeks of treatment the IBD exacerbation rate was 17% (14/82) in the etoricoxib group compared to 19% (15/77) in the placebo group (RR 0.88, 95% CI 0.45 to 1.69). A GRADE analysis indicated that the overall quality of the evidence supporting this outcome was low due to very sparse data (29 events). There was no statistically significant difference in exacerbation of ulcerative colitis between celecoxib and placebo. After two weeks of treatment 4% (5/112) of celecoxib patients experienced an exacerbation of ulcerative colitis compared to 6% (7/110) of patients in the placebo group (RR 0.70, 95% CI 0.23 to 2.14). A GRADE analysis indicated that the overall quality of the evidence supporting this outcome was low due to very sparse data (12 events). The study comparing etoricoxib to placebo documented but did not report on AEs. The proportion of patients who experienced AEs was similar in the celecoxib and placebo groups (21% and 17%, respectively, P > 0.20). No patients in either group died or experienced serious adverse events. Eleven percent of patients in the celecoxib and placebo groups experienced GI AEs (RR 0.97, 95% CI 0.46 to 2.07). A GRADE analysis indicated that the overall quality of the evidence supporting this outcome was low due to very sparse data (24 events). GI AEs led to premature withdrawal from the study in 3% of patients in celecoxib and placebo groups respectively. GI AEs included increased stool frequency, rectal bleeding, and inflamed mucosa. No patients experienced any cardiovascular adverse events. Renal toxicity or thrombotic AEs were not reported.

AUTHORS' CONCLUSIONS

The results for disease exacerbation and AEs between the COX-2 inhibitors celecoxib and etoricoxib and placebo were uncertain. Thus no definitive conclusions regarding the tolerability and safety of the short term use of celecoxib and etoricoxib in patients with IBD can be drawn. The two included studies suggest that celecoxib and etoricoxib do not exacerbate IBD symptoms. However, it should be noted that both studies had relatively small sample sizes and short follow-up durations. Clinicians need to continue to weigh the risks and benefits of these drugs when treating patients IBD patients with rheumatological manifestations in order to avoid disease exacerbation and other adverse effects. Further RCTs are needed to determine the tolerability and safety of celecoxib and etoricoxib in these patients.

Reactive oxygen species-scavenging nanomedicines for the treatment of oxidative stress injuries

This Progress Report describes a development of two types of reactive oxygen species (ROS)-scavenging nanomedicines for the treatment of oxidative stress injuries, referred to as pH-sensitive redox nanoparticle (RNP(N) ) and pH-insensitive redox nanoparticle (RNP(O) ), which are prepared by self-assembling amphiphilic block copolymers possessing nitroxide radicals as a side chain of hydrophobic segment via amine and ether linkages, respectively. Due to a protonation of amino groups in hydrophobic core, RNP(N) disintegrates in low pH environments such as ischemic, inflamed, and tumor tissues, resulting in increased ROS-scavenging activity because of the exposed nitroxide radicals from the core. Utilizing pH-responsiveness of RNP(N) , it shows remarkable therapeutic effects on oxidative stress injuries such as renal and cerebral ischemia-reperfusion injuries after intravenous administration. Moreover, RNP(N) shows an enhancement of the activity of anticancer drugs by suppression of activation of transcription factors in tumor due to the ROS scavenging. On the other hand, orally administered RNP(O) has notable characteristics such as preferential accumulation in mucosa and inflamed area of gastrointestinal tract and no uptake into blood stream. Based on these characters, RNP(O) shows a remarkable therapeutic effect for the gastrointestinal inflammation without any adverse effects. Thus, ROS-scavenging nanomedicines have therapeutic efficacy in numerous oxidative stress diseases.

Cherry-tree colon: colonoscopic appearance suggesting drug-induced mucosal injury

Drug-induced damage to the gastrointestinal mucosa has been mainly focused on damage in the upper tract. However, increasing evidence suggests that commonly used drugs may also affect the mucosa of the lower gut, and particularly in the colon. The aim of this study was to report that fairly homogeneous colonoscopic findings, correlate with histological evidence of drug-induced mucosal injury. Charts of patients with the "cherry tree" colonoscopic aspect were reviewed to correlate the endoscopic and histological findings for a possible association with the use of drugs. Data from 29 patients (5 men, 24 women, age range 16-76 years) with the "cherry tree" colonoscopic findings were analyzed. Histology revealed an increase in eosinophils in the left colon in 23 patients, pseudomelanosis coli in 3, and microscopic colitis in 3. The findings were associated with proton pump inhibitors in 19 (65.5 %), non-steroidal anti-inflammatory drugs or statins (3 cases each), and other drugs [4 cases, including estroprogestinics (1), antidepressants (2), and thyroxin (1)]. The "cherry tree" colonoscopic appearance suggests drug-induced colonic damage. Awareness of this association may prevent unnecessary, expensive and time-consuming procedures.

NSAID-induced enteropathy: are the currently available selective COX-2 inhibitors all the same?

Nonsteroidal anti-inflammatory drugs (NSAIDs) can induce intestinal mucosal damage, but the underlying mechanisms remain poorly understood. The present study investigated the effects of celecoxib, etoricoxib, indomethacin, and diclofenac on small bowel integrity in rats. Male rats were treated orally with test drugs for 14 days. Animals were processed for assessment of blood hemoglobin levels and hepatic mitochondrial functions, microscopic evaluation of small intestinal damage, Western blot analysis of cyclooxygenase-1 and -2 (COX-1, COX-2) expression, and assay of malondialdehyde (MDA), myeloperoxidase (MPO), and prostaglandin E2 (PGE2) levels in small intestine. Indomethacin and diclofenac decreased blood hemoglobin levels, whereas etoricoxib and celecoxib were without effects. Celecoxib caused a lower degree of intestinal damage in comparison with the other test drugs. Indomethacin and diclofenac, but not etoricoxib or celecoxib, reduced intestinal PGE2 levels. Test drugs did not modify intestinal COX-1 expression, although they enhanced COX-2, with the exception of celecoxib, which downregulated COX-2. Indomethacin, diclofenac, and etoricoxib altered mitochondrial respiratory parameters, although celecoxib was without effects. Indomethacin or diclofenac increased MDA and MPO levels in both jejunum and ileum. In the jejunum, etoricoxib or celecoxib did not modify such parameters, whereas in the ileum, etoricoxib, but not celecoxib, increased both MDA and MPO levels. These findings suggest that nonselective NSAIDs and etoricoxib can induce enteropathy through a topic action, whereas celecoxib lacks relevant detrimental actions. The selectivity profile of COX-1/COX-2 inhibition by test drugs and the related effects on prostaglandin production do not appear to play a major role in the pathogenesis of enteropathy.

Antibiotics Protect against Septic Shock in Mice Administered β-Glucan and Indomethacin

We have developed an animal model of sepsis in mice by repeatedly administering beta-glucan, a biological response modifier, and indomethacin (IND), a nonsteroidal anti-inflammatory drug. The combination of these drugs induced bacteremia by translocation of the enterobacterial flora, resulting in increasing the number of activated leukocytes, and inducing hyper cytokinemia. In the present study, we examined the effect of antibiotics on beta-glucan and IND-induced septic shock. Treatment with antibiotics inhibited microbial translocation, inhibited contraction of the colon, reduced lipopolysaccharides (LPS)-elicited production of TNF-alpha and IL-6, and finally prolonged survival. However, the efficacy of antibiotics treatment was limited in mice administered IND orally. These findings strongly suggested that the antibiotics controlled the gut-associated action of IND and reduced various symptoms accompanying sepsis.

Sulindac activates NF-κB signaling in colon cancer cells

BACKGROUND

The non-steroidal anti-inflammatory drug (NSAID) sulindac has shown efficacy in preventing colorectal cancer. This potent anti-tumorigenic effect is mediated through multiple cellular pathways but is also accompanied by gastrointestinal side effects, such as colon inflammation. We have recently shown that sulindac can cause up-regulation of pro-inflammatory factors in the mouse colon mucosa. The aim of this study was to determine the signaling pathways that mediate the transcriptional activation of pro-inflammatory cytokines in colon cancer epithelial cells treated with sulindac sulfide.

RESULTS

We found that sulindac sulfide increased NF-κB signaling in HCT-15, HCT116, SW480 and SW620 cells, although the level of induction varied between cell lines. The drug caused a decrease in IκBα levels and an increase of p65(RelA) binding to the NF-κB DNA response element. It induced expression of IL-8, ICAM1 and A20, which was inhibited by the NF-κB inhibitor PDTC. Sulindac sulfide also induced activation of the AP-1 transcription factor, which co-operated with NF-κB in up-regulating IL-8. Up-regulation of NF-κB genes was most prominent in conditions where only a subset of cells was undergoing apoptosis. In TNFα stimulated conditions the drug treatment inhibited phosphorylation on IκBα (Ser 32) which is consistent with previous studies and indicates that sulindac sulfide can inhibit TNFα-induced NF-κB activation. Sulindac-induced upregulation of NF-κB target genes occurred early in the proximal colon of mice given a diet containing sulindac for one week.

CONCLUSIONS

This study shows for the first time that sulindac sulfide can induce pro-inflammatory NF-κB and AP-1 signaling as well as apoptosis in the same experimental conditions. Therefore, these results provide insights into the effect of sulindac on pro-inflammatory signaling pathways, as well as contribute to a better understanding of the mechanism of sulindac-induced gastrointestinal side effects.

A 9-year evaluation of temporal trends in alosetron postmarketing safety under the risk management program

OBJECTIVES

Adverse events (AEs) of ischemic colitis (IC) and complications of constipation (CoC) associated with alosetron are rare and have been adjudicated during the first 5.5 years of the risk management program (RMP); however, changes in incidence rates relative to reductions in AE reports and increases in alosetron prescriptions over the 9-year RMP have not been evaluated. The authors aim to evaluate temporal trends in alosetron postmarketing safety over the 9-year RMP.

METHODS

The alosetron safety database was searched to identify cases of IC, CoC, and related AEs from 20 November 2002 to 31 December 2011. Adjudication of IC and CoC cases were based on US Food and Drug Administration-defined criteria. Incidence rates were calculated using the number of AEs and alosetron prescriptions (expressed as cases/1000 patient-years exposure).

RESULTS

A total of 29 cases were adjudicated as probable/possible IC and 7 cases were adjudicated as CoC. Cumulative adjudicated incidence rate of IC (1.03 cases/1000 patient-years) is low and stable, while that of CoC (0.25 cases/1000 patient-years) is low, declining progressively over time. Decreases in the incidence rates of potential symptoms of IC (abdominal pain with bloody diarrhea/hematochezia) and CoC (constipation) were also observed.

CONCLUSIONS

Over the 9-year RMP period, incidence rates of IC and CoC remain rare. Substantial reductions over time were observed in the incidence of CoC and in symptoms suggestive of IC or CoC, while IC incidence has been stable at approximately 1.0 case/1000 patient-years. Decreases in AEs and serious outcomes associated with IC and CoC since the reintroduction of alosetron are likely attributable to the RMP.

Proton pump inhibitors are not the key for therapying non-steroidal anti-inflammatory drugs-induced small intestinal injury

The ability of non-steroidal anti-inflammatory drugs (NSAIDs) to injure the small intestine has been well established in humans and animals. Proton pump inhibitors (PPIs) are frequently prescribed to reduce gastric and duodenal injury caused in high-risk patients taking NSAIDs. However, scarce information is available concerning the effects of PPIs on intestinal damage induced by NSAIDs, and the suppression of gastric acid secretion by PPIs is hard to provide any protection against the damage caused by NSAIDs in the small intestine. The present study was designed to examine the effects of intragastric treatment of two PPIs widely used in clinical practice, namely omeprazole and pantoprazole, on the intestinal damage induced by administration of diclofenac in rat. Male SD rats were treated with omeprazole or pantoprazole for 9 days, with concomitant treatment with anti-inflammatory doses of diclofenac on the final 5 days. The anatomical lesion, villous height, the thickness, and the section area of small intestine were quantitatively analyzed. The change of ultrastructural organization was observed. Endotoxin level in blood was measured by photometry. Epidermal growth factor was observed by immunohistochemistry. Omeprazole and pantoprazole didn't decrease the macroscopic and histologic damage induced by diclofenac in the rat's small intestine. In the two PPI groups, villous height was (89.6 ± 11.8 and 92.6 ± 19.3 μm) lower than which of the control group (P < 0.05). The thickness became thinning, and the section area became small. LPS levels in the portal blood of omeprazole and pantoprazole were (4.36 ± 1.26 and 4.25 ± 1.17 EU/ml), significantly higher than in controls (P < 0.05). The EFG of PPI group descended significantly compared with the control group (P < 0.05). Omeprazole and pantoprazole cannot protect the small intestine from the damage induced by diclofenac in the conscious rat. PPIs cannot repair NSAID-induced intestinal damage at least in part because of significant lesion in mechanical barrier function and reduction in epidermal growth factor.

Targeting cyclooxygenase-2 in depression is not a viable therapeutic approach and may even aggravate the pathophysiology underpinning depression

Depression is a complex progressive disorder accompanied by activation of inflammatory and Th-1 driven pathways, oxidative and nitrosative stress (O&NS), lowered antioxidant levels, mitochondrial dysfunctions, neuroprogression and increased bacterial translocation. In depression, activation of immuno-inflammatory pathways is associated with an increased risk for cardio-vascular disorder (CVD). Because of the inflammatory component, the use of cyclooxygenase 2 (COX-2) inhibitors, such as celecoxib, has been advocated to treat depression. Electronic databases, i.e. PUBMED, Scopus and Google Scholar were used as sources for this selective review on the effects of COX-2 inhibitors aggravating the abovementioned pathways. COX-2 inhibitors may induce neuroinflammation, exacerbate Th1 driven responses, increase lipid peroxidation, decrease the levels of key antioxidants, damage mitochondria and aggravate neuroprogression. COX-2 inhibitors may aggravate bacterial translocation and CVD through Th1-driven mechanisms. COX-2 inhibitors may aggravate the pathophysiology of depression. Since Th1 and O&NS pathways are risk factors for CVD, the use of COX-2 inhibitors may further aggravate the increased risk for CVD in depression. Selectively targeting COX-2 may not be a viable therapeutic approach to treat depression. Multi-targeting of the different pathways that play a role in depression is more likely to yield good treatment results.

Bioactivity-guided isolation of ethyl-p-methoxycinnamate, an anti-inflammatory constituent, from Kaempferia galanga L. extracts

This study evaluated the anti-inflammatory effect of Kaempferia galanga (KG) using an activity-guided approach. KG rhizomes were serially extracted with petroleum ether, chloroform, methanol and water. These extracts (2 g/kg each) were tested for their ability to inhibit carrageenan-induced rat paw edema. The chloroform extract was found to exert the highest inhibition (42.9%) compared to control (p < 0.001), hence it was further fractionated by washing serially with hexane, hexane-chloroform (1:1) and chloroform. The chloroform fraction (1 g/kg) showed the highest inhibitory effect (51.9%, p < 0.001) on carrageenan-induced edema. This chloroform fraction was further fractionated with hexane-chloroform (1:3) and chloroform, and of the two fractions, the hexane-chloroform sub-fraction was the most effective in inhibiting edema (53.7%, p < 0.001). GC-MS analysis of the active sub-fraction identified ethyl-p-methoxycinnamate (EPMC) as the major component, which was re-crystallized. EPMC dose-dependently inhibited carrageenan-induced edema with an MIC of 100 mg/kg. Moreover, in an in vitro study, EPMC non-selectively inhibited the activities of cyclooxygenases 1 and 2, with IC₅₀ values of 1.12 µM and 0.83 µM respectively. These results validate the anti-inflammatory activity of KG which may be exerted by the inhibition of cyclooxygenases 1 and 2. EPMC isolated from this plant may be the active anti-inflammatory agent.

Prevention and management of non-steroidal anti-inflammatory drugs-induced small intestinal injury

Non-steroidal anti-inflammatory drug (NSAID)-induced small bowel injury is a topic that deserves attention since the advent of capsule endoscopy and balloon enteroscopy. NSAID enteropathy is common and is mostly asymptomatic. However, massive bleeding, stricture, or perforation may occur. The pathogenesis of small intestine injury by NSAIDs is complex and different from that of the upper gastrointestinal tract. No drug has yet been developed that can completely prevent or treat NSAID enteropathy. Therefore, a long-term randomized study in chronic NSAID users is needed.

Haemoglobin decreases in NSAID users over time: an analysis of two large outcome trials

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) have been associated with clinically significant decreases in haemoglobin dependent and independent of acute bleeding events.

AIM

To evaluate the incidence and time to a clinically meaningful decrease in haemoglobin in two double-blind, prospective randomised clinical trials comparing NSAIDs in patients with osteoarthritis (OA) or rheumatoid arthritis (RA).

METHODS

In CLASS, patients with OA/RA who were aged ≥ 18 years and required continuous NSAID treatment were included; patients who were Helicobacter pylori positive and/or using aspirin were not excluded. In contrast, in the CONDOR trial, comparing celecoxib alone to diclofenac sustained release (plus omeprazole), patients were aged ≥ 60 years or ≥ 18 years with a history of gastroduodenal ulcer and were H. pylori negative; aspirin or other anti-platelet users were excluded. To make a parallel post hoc analysis we limited our study to 6 months and the populations to only the non-aspirin users in CLASS and those patients receiving either celecoxib or diclofenac. A decrease in haemoglobin of ≥ 2 g/dL defined the primary end point.

RESULTS

At 6 months, in the CLASS and CONDOR trials, 1.9% and 2.0% of patients treated with celecoxib and 3.3% and 5.7% of patients treated with diclofenac developed a ≥ 2 g/dL decrease in haemoglobin, respectively, [CLASS: odds ratio (OR) 1.80 (95% confidence interval (CI), 1.22-2.65) and CONDOR: OR 2.93 (95% CI, 2.06-4.15), respectively].

CONCLUSION

IN these two large, independent trials, clinically-meaningful decreases in haemoglobin ≥ 2 g/dL occurred in a relatively similar fashion over time despite differences in trial designs.

Clinical patterns and outcomes of ischaemic colitis: results of the Working Group for the Study of Ischaemic Colitis in Spain (CIE study)

BACKGROUND

There is a lack of prospective studies evaluating the natural history of colonic ischaemia (CI). We performed such a study to evaluate the clinical presentation, outcome, and mortality as well as clinical variables associated with poor prognosis.

METHODS

An open, prospective, and multicentre study was conducted in 24 Spanish hospitals serving a population of 3.5 million people. The study included only patients who met criteria for definitive or probable CI. A website (www.colitisisquemica.org) provided logistical support.

RESULTS

A total of 364 patients met criteria for inclusion. CI was suspected clinically in only 24.2% of cases. The distribution of clinical patterns was as follows: reversible colopathy (26.1%), transient colitis (43.7%), gangrenous colitis (9.9%), fulminant pancolitis (2.5%), and chronic segmental colitis (17.9%). A total of 47 patients (12.9%) had an unfavorable outcome as defined by mortality and/or the need for surgery. Multivariate analysis identified the following signs as independent risk factors for an unfavorable outcome: abdominal pain without rectal bleeding [odds ratio (OR) 3.9; 95% confidence interval (CI) = 1.6-9.3], non-bloody diarrhoea (OR 10; 95% CI = 3.7-27.4), and peritoneal signs (OR 7.3; 95% CI = 2.7-19.6). Unfavorable outcomes also were more frequent in isolated right colon ischaemia (IRCI) compared with non-IRCI (40.9 vs. 10.3%, respectively; p < 0.0001). The overall mortality rate was 7.7%.

CONCLUSIONS

The clinical presentation of CI is very heterogeneous, perhaps explaining why clinical suspicion of this disease is so low. The presence of IRCI, and occurrence of peritoneal signs or onset of CI as severe abdominal pain without bleeding, should alert the physician to a potentially unfavorable course.

Diazoxide attenuates indomethacin-induced small intestinal damage in the rat

ATP-sensitive potassium (K(ATP)) channel openers have been shown to protect against cellular damage in neurons, cardiac muscle, and kidney and to effectively reduce nonsteroidal anti-inflammatory drug (NSAID)-induced gastric damage in rats. We investigated the effects of K(ATP) channel opener diazoxide on small intestinal injury induced in rats by indomethacin administration. The effect of glibenclamide, a K(ATP) channel blocker, was also evaluated. Diazoxide (15, 45 and 135mg/kg) or glibenclamide (18mg/kg), were given by oral gavage 1h before and 6h after indomethacin treatment (20mg/kg p.o.). After 24h, macroscopic and histologic lesions, myeloperoxidase (MPO) activity and lipid peroxidation levels were evaluated. Diazoxide at 15mg/kg was ineffective, while at doses of 45mg/kg and 135mg/kg was able to significantly improve all damage parameters. Glibenclamide administration enhanced intestinal injury. These results show for the first time a beneficial effect of diazoxide in indomethacin-induced enteritis in the rat. Several mechanisms, such as oxidative phosphorylation uncoupling and hypermotility seem particularly important in NSAID-induced intestinal injury. Such events lead to increased mucosal permeability and to penetration of noxious lumen components, which ignite the inflammatory response. Since K(ATP) channel openers were shown to protect against mitochondrial damage, to reduce intercellular permeability and to relax smooth muscle, we suggest that diazoxide could exert its beneficial effects by one or more of these actions.

cPLA2 is protective against COX inhibitor-induced intestinal damage

Cytosolic phospholipase A(2) (cPLA(2)) is the rate-limiting enzyme responsible for the generation of prostaglandins (PGs), which are bioactive lipids that play critical roles in maintaining gastrointestinal (GI) homeostasis. There has been a long-standing association between administration of cyclooxygenase (COX) inhibitors and GI toxicity. GI injury is thought to be induced by suppressed production of GI-protective PGs as well as direct injury to enterocytes. The present study sought to determine how pan-suppression of PG production via a genetic deletion of cPLA(2) impacts the susceptibility to COX inhibitor-induced GI injury. A panel of COX inhibitors including celecoxib, rofecoxib, sulindac, and aspirin were administered via diet to cPLA(2)(-/-) and cPLA(2)(+/+) littermates. Administration of celecoxib, rofecoxib, and sulindac, but not aspirin, resulted in acute lethality (within 2 weeks) in cPLA(2)(-/-) mice, but not in wild-type littermates. Histomorphological analysis revealed severe GI damage following celecoxib exposure associated with acute bacteremia and sepsis. Intestinal PG levels were reduced equivalently in both genotypes following celecoxib exposure, indicating that PG production was not likely responsible for the differential sensitivity. Gene expression profiling in the small intestines of mice identified drug-related changes among a panel of genes including those involved in mitochondrial function in cPLA(2)(-/-) mice. Further analysis of enterocytic mitochondria showed abnormal morphology as well as impaired ATP production in the intestines from celecoxib-exposed cPLA(2)(-/-) mice. Our data demonstrate that cPLA(2) appears to be an important component in conferring protection against COX inhibitor-induced enteropathy, which may be mediated through affects on enterocytic mitochondria.

Ischemic colitis and complications of constipation associated with the use of alosetron under a risk management plan: clinical characteristics, outcomes, and incidences

OBJECTIVES

Alosetron is a potent, selective 5-HT(3) receptor antagonist prescribed for women with severe diarrhea-predominant irritable bowel syndrome (IBS-D) under a risk management plan (RMP). The RMP was implemented following cases of ischemic colitis (IC) and complications of constipation (CoC) associated with the use of alosetron. The objectives of this study were to characterize IC and CoC clinical features, outcomes, and incidence rates in the new restricted patient population to evaluate the effectiveness of the RMP in the prevention of serious outcomes.

METHODS

Safety data from adverse event reporting from November 2002 through June 2008 were reviewed for probable and possible IC and CoC using the US Food and Drug Administration/sponsor-defined criteria and definitions. Evidence for IC included medical documentation, colonoscopy, and sigmoidoscopy+/-biopsy. Evidence for CoC included medical history and confirmation from health-care professionals.

RESULTS

Within the inclusion dates, 29,072 patients received 203,939 alosetron prescriptions. Although the absolute numbers of IC and CoC cases have declined, the incidence rates for IC and CoC (0.95 and 0.36 cases per 1,000 patient-years, respectively) were similar to rates during the postmarketing cycle before alosetron withdrawal. In patients with severe IBS-D receiving alosetron (n=998) or placebo (n=411) in clinical trials since reintroduction, incidence rates for IC were 4 and 2 cases per 1,000 patients, respectively. Rates for CoC were 2 and 0 cases per 1,000 patients in the alosetron and placebo groups, respectively. No mesenteric ischemia, surgeries, transfusions, or deaths occurred in patients with IC and no cases of CoC were associated with toxic megacolon, perforation, surgeries, transfusions, or deaths. IC and CoC cases were typically of short duration and all improved on prompt withdrawal of alosetron.

CONCLUSIONS

Serious outcomes associated with IC and CoC appear to be mitigated since introduction of alosetron under the RMP.

Gastrointestinal and liver side effects of drugs in elderly patients

It is expected that the percentage of people >60 years of age will be 22% worldwide by the year 2050. Multi-morbidity and poly-pharmacy are common in individuals during old age, while adverse drug reactions are at least twice as common in the elderly compared to younger adults. Publications related to drug side effects are rather rare in this age group since most clinical trials exclude patients >75-80 years of age. Gastrointestinal adverse drug reactions studied in the elderly include non-steroidal anti-inflammatory drugs (NSAIDs) and anticoagulant-induced gastrointestinal tract mucosal injuries. Malabsorption, diarrhoea and constipation are common side effects of laxatives, antibiotics, anticholinergics and calcium channel blockers. Drug (amoxycilin/clavulanic acid, isoniazide, nitrofurantoin, diclifenac and methotrexate)-induced hepatotoxicity in the elderly is four times more common than in younger adults and may simulate almost all known liver disorders. Further clinical studies are needed to investigate gastrointestinal and hepatic side effects of drugs in elderly patients.

Exacerbation of inflammatory bowel diseases associated with the use of nonsteroidal anti-inflammatory drugs: myth or reality?

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs), conventional and selective cyclooxygenase-2 (COX-2) inhibitors, are among the most widely used medications for the treatment of various inflammatory conditions. There is strong evidence of a possible association between the use of these drugs and the relapse of inflammatory bowel diseases (IBD).

OBJECTIVE

Our objective was to examine the literature regarding the exacerbation of IBD associated with the use of conventional NSAIDs and selective COX-2 inhibitors and the underlying pathogenetic mechanisms.

STUDY DESIGN

We reviewed articles, including original papers, controlled trials, case reports, reviews, and editorials published in English at the PubMed, Scopus Database, and Science Direct database, searching with the following keywords: nonsteroidal anti-inflammatory drugs (NSAIDs), COX-2 inhibitors, Coxibs, inflammatory bowel diseases (IBD), ulcerative colitis (UC), Crohn's disease (CD).

RESULTS

There is substantial evidence that exacerbation of IBD happens after treatment with NSAIDs, but the available data remain conflicting, and it is not clear whether selective COX-2 inhibitors are safer than traditional NSAIDs. However, there is some evidence that selective COX-2 inhibition and COX-1 inhibition (with low-dose aspirin) appear to be well-tolerated in the short term. Regarding the mechanisms of relapse, the reduction of prostaglandins appears to be the hallmark of the NSAIDs adverse effects.

CONCLUSIONS

Further randomized, double-blind, controlled trials should be performed to address this issue, and more in vitro studies to identify the pathways involved are required.

Lupus mesenteric vasculitis can cause acute abdominal pain in patients with SLE

Lupus mesenteric vasculitis (LMV) is a unique clinical entity found in patients who present with gastrointestinal manifestations of systemic lupus erythematosus, and is the main cause of acute abdominal pain in these patients. LMV usually presents as acute abdominal pain with sudden onset, severe intensity and diffuse localization. Other causes of abdominal pain, such as acute gastroenteritis, peptic ulcers, acute pancreatitis, peritonitis, and other reasons for abdominal surgery should be ruled out. Prompt and accurate diagnosis of LMV is critical to ensure implementation of appropriate immunosuppressive therapy and avoidance of unnecessary surgical intervention. The pathology of LMV comprises immune-complex deposition and complement activation, with subsequent submucosal edema, leukocytoclastic vasculitis and thrombus formation; most of these changes are confined to small mesenteric vessels. Abdominal CT is the most useful tool for diagnosing LMV, which is characterized by the presence of target signs, comb signs, and other associated findings. The presence of autoantibodies against phospholipids and endothelial cells might provide information about the likelihood of recurrence of LMV. Immediate, high-dose, intravenous steroid therapy can lead to a favorable outcome and prevent serious complications such as bowel ischemia, necrosis and perforation.

NSAIDs-induced diaphragm-like colonic strictures: a case report

A 48-year-old woman presented with a 2-week history of diarrhoea and abdominal pain. No overt gastrointestinal bleeding was reported and there was no history of loss of weight or loss of appetite. General and abdominal examination was unremarkable except for subconjunctival pallor. The haemoglobin was 7.1 g/dl at presentation with the peripheral blood film indicating iron deficiency anaemia. An urgent colonoscopy revealed two strictures within a 5 cm segment of transverse colon. The distal stricture showed significant ulceration and inflammation, while the proximal one showed an impassable "diaphragm-like" stricture. Biopsies from both of the strictures showed chronic inflammatory infiltrate with numerous eosinophils and no evidence of malignancy. The patient had been taking enteric-coated diclofenac tablets 50 mg three times daily over the past 10 years for chronic backache. Her bowel symptoms resolved significantly within 4 weeks of stopping diclofenac and she continued to remain relatively asymptomatic at 3 months follow-up.