Anti-tumour necrosis factor agents reduce non-steroidal anti-inflammatory drug-induced small bowel injury in rheumatoid arthritis patients

DA-9601 has protective effects comparable to those of proton pump inhibitor and rebamipide against nonsteroidal anti-inflammatory drugs-induced upper and lower gastrointestinal bleeding in patients with rheumatoid arthritis: A nationwide study using Korean Health Insurance Review and Assessment Service database

DA-9601 extracted from Artemisia asiatica contains a bioactive compound - eupatilin - that can protect against gastric mucosal damage through anti-inflammatory and anti-oxidative properties and is approved for treating acute and chronic gastritis in Korea, but their ability to protect gastrointestinal (GI) bleeding caused by nonsteroidal anti-inflammatory drugs (NSAIDs) is unclear. We aimed to compare the protective effects of DA-9601 to those of proton pump inhibitors (PPI) and rebamipide against upper and lower GI bleeding in patients with rheumatoid arthritis (RA) undergoing long-term NSAIDs therapy using the Korean Health Insurance Review and Assessment database. In this nationwide retrospective cohort study, we evaluated patients with RA who concurrently received NSAIDs for >3 months with DA-9601, PPI, or rebamipide between January 2015 and December 2017. The index date was the date of NSAIDs initiation, and all patients were followed up until December 2020 to detect upper and lower GI bleeding. In total, 24,258 patients with RA were eligible, and 5468 (22.5%), 4417 (18.2%), and 14,373 (59.3%) received DA-9601, PPI, or rebamipide, respectively, on the index date. During follow-up, upper and lower GI bleeding occurred in 508 (2.1%) and 402 (1.6%) patients with RA, respectively. The incidence rate of upper and lower GI bleeding was 615/100,000 and 485/100,000 person-years, respectively. Among patients with RA receiving DA-9601, PPI, or rebamipide, the frequencies of NSAIDs-induced upper GI bleeding were 0.5%, 0.4%, and 1.2%, respectively. The frequencies of NSAIDs-induced lower GI bleeding were 0.4%, 0.4%, and 0.9%, respectively. The incidence of NSAIDs-induced upper GI bleeding in patients with RA receiving DA-9601, PPI, and rebamipide was 601/100,000, 705/100,000, and 596/100,000 person-years, respectively, while the incidence of NSAIDs-induced lower GI bleeding in the same groups was 449/100,000, 608/100,000, and 465/100,000 person-years, respectively. In the multivariate Cox regression analysis, no significant difference was observed in lower and upper GI bleeding hazards between patients with RA using DA-9601, PPI, and rebamipide. Our results suggest that DA-9601 may exhibit protection against NSAIDs-induced GI bleeding that is comparable to those of PPI and rebamipide in patients with RA.

Progression of Gastrointestinal Injury During Antiplatelet Therapy After Percutaneous Coronary Intervention: A Secondary Analysis of the OPT-PEACE Randomized Clinical Trial

Importance

Gastrointestinal injury progression induced by antiplatelet therapy in patients after percutaneous coronary intervention (PCI) has not been well studied.

Objective

To assess the association of aspirin, clopidogrel, and their combination with gastrointestinal injury progression among patients without high bleeding risk after PCI.

Design, Setting, and Participants

This secondary analysis assessed data from the Optimal Antiplatelet Therapy for Prevention of Gastrointestinal Injury Evaluated by ANKON Magnetically Controlled Capsule Endoscopy (OPT-PEACE) double-masked, placebo-controlled, multicenter randomized clinical trial. The OPT-PEACE trial was conducted at 28 centers in China, and recruitment took place from July 13, 2017, to July 13, 2019. The trial included patients with stable coronary artery disease or acute coronary syndromes without ST-segment elevation after PCI. Statistical analysis was conducted from September 13, 2022, to January 23, 2023.

Interventions

Patients underwent magnetically controlled capsule endoscopy (MCE) at baseline and after 6 months of dual antiplatelet therapy (DAPT) with aspirin (100 mg/d) plus clopidogrel (75 mg/d). Those with no evidence of gastrointestinal ulcers or bleeding (ie, the intention-to-treat [ITT] cohort) were randomized (1:1:1) to aspirin (100 mg/d) plus matching placebo (aspirin alone), clopidogrel (75 mg/d) plus matching placebo (clopidogrel alone), or DAPT for an additional 6 months. A third MCE was performed 12 months after PCI.

Main Outcomes and Measures

The primary outcome was the rate of gastric injury progression as assessed with the results of the 3 MCEs (at baseline, 6 months, and 12 months) in the modified intention-to-treat (mITT) population. The key secondary outcome was the rate of small-intestinal injury progression. Gastric or small-intestinal injury progression was defined as a quantitative increase in erosions or ulcers between the second and third MCEs (at 6 and 12 months, respectively).

Results

This study included the 394 patients in the mITT cohort. Their mean (SD) age was 56.9 (8.7) years, and most were men (296 [75.1%]). A total of 132 patients were randomized to aspirin alone, 132 to clopidogrel alone, and 130 to DAPT. Gastric injury progression occurred in 49 aspirin users (37.1%), 64 clopidogrel users (48.5%), and 69 DAPT users (53.1%) (P = .02), reflecting a lower rate of gastric injury progression among aspirin users vs DAPT users (risk ratio [RR], 0.70 [95% CI, 0.49-0.99]; P = .009). No significant difference was observed between clopidogrel alone and DAPT (48.5% vs 53.1%; P = .46) or between aspirin alone and clopidogrel alone (37.1% vs 48.5%; P = .06). A total of 51 aspirin users (38.6%), 65 clopidogrel users (49.2%), and 71 DAPT users (54.6%) (P = .03) developed progressive small-intestinal injury, reflecting a lower rate of small-intestinal injury among aspirin users vs DAPT users (RR, 0.71 [95% CI, 0.50-0.99]; P = .01). No difference was observed between patients treated with clopidogrel vs DAPT (49.2% vs 54.6%; P = .38) or with aspirin vs clopidogrel (38.6% vs 49.2%; P = .08).

Conclusions and Relevance

In this secondary analysis of a randomized clinical trial, ongoing use of aspirin, clopidogrel, or their combination between 6 and 12 months after PCI was associated with progressive gastric and small-intestinal injury in a substantial proportion of patients, more so with DAPT than with monotherapy. Clopidogrel was at least as likely as aspirin to induce gastrointestinal injury progression. Future research is warranted to determine what impact the findings from MCEs would have on decision-making of antiplatelet therapy.

Trial Registration

ClinicalTrials.gov Identifier: NCT03198741.

Sanguinarine protects against indomethacin-induced small intestine injury in rats by regulating the Nrf2/NF-κB pathways

In recent years, small intestine as a key target in the treatment of Inflammatory bowel disease caused by NSAIDs has become a hot topic. Sanguinarine (SA) is one of the main alkaloids in the Macleaya cordata extracts with strong pharmacological activity of anti-tumor, anti-inflammation and anti-oxidant. SA is reported to inhibit acetic acid-induced colitis, but it is unknown whether SA can relieve NSAIDs-induced small intestinal inflammation. Herein, we report that SA effectively reversed the inflammatory lesions induced by indomethacin (Indo) in rat small intestine and IEC-6 cells in culture. Our results showed that SA significantly relieved the symptoms and reversed the inflammatory lesions of Indo as shown in alleviation of inflammation and improvement of colon macroscopic damage index (CMDI) and tissue damage index (TDI) scores. SA decreased the levels of TNF-α, IL-6, IL-1β, MDA and LDH in small intestinal tissues and IEC-6 cells, but increased SOD activity and ZO-1 expression. Mechanistically, SA dose-dependently promoted the expression of Nrf2 and HO-1 by decreasing Keap-1 level, but inhibited p65 phosphorylation and nuclear translocation in Indo-treated rat small intestine and IEC-6 cells. Furthermore, in SA treated cells, the colocalization between p-p65 and CBP in the nucleus was decreased, while the colocalization between Nrf2 and CBP was increased, leading to the movement of gene expression in the nucleus to the direction of anti-inflammation and anti-oxidation. Nrf2 silencing blocked the effects of SA. Together our results suggest that SA can significantly prevent intestinal inflammatory lesions induced by Indo in rats and IEC-6 cells through regulation of the Nrf2 pathway and NF-κBp65 pathway.

NSAID-Associated Small Intestinal Injury: An Overview From Animal Model Development to Pathogenesis, Treatment, and Prevention

With the wide application of non-steroidal anti-inflammatory drugs (NSAIDs), their gastrointestinal side effects are an urgent health burden. There are currently sound preventive measures for upper gastrointestinal injury, however, there is a lack of effective defense against lower gastrointestinal damage. According to a large number of previous animal experiments, a variety of NSAIDs have been demonstrated to induce small intestinal mucosal injury in vivo. This article reviews the descriptive data on the administration dose, administration method, mucosal injury site, and morphological characteristics of inflammatory sites of various NSAIDs. The cells, cytokines, receptors and ligands, pathways, enzyme inhibition, bacteria, enterohepatic circulation, oxidative stress, and other potential pathogenic factors involved in NSAID-associated enteropathy are also reviewed. We point out the limitations of drug modeling at this stage and are also pleased to discover the application prospects of chemically modified NSAIDs, dietary therapy, and many natural products against intestinal mucosal injury.

Review article: drug-induced small bowel injury

BACKGROUND

Drug-induced gastrointestinal injury has been increasingly reported, but its exact incidence is not known. The small and large intestines represent the most affected sites of injury, accounting for 20%-40% of all gastrointestinal side effects.

AIM

To provide an updated literature review detailing medications linked to the development of small bowel injury.

METHODS

We conducted a literature search on PubMed from its inception to May 1, 2021. We included English-language original studies, meta-analyses, systematic reviews, review articles and case reports.

RESULTS

Drug-induced enteropathy can range from asymptomatic histological changes resulting in a subtle, self-limited disease to a chronic inflammatory condition mimicking inflammatory bowel disease, or bowel perforation. Endoscopy can demonstrate erythema, mucosal friability, oedema, erosions, ulcers or strictures in severe cases. Histology may include mucosal erosions and ulcerations, focal active enteritis, villous atrophy, epithelial apoptosis or necrotising enteritis. A well-established association has been found with the use of nonsteroidal anti-inflammatory drugs, immunosuppressants, chemotherapeutic agents, antibiotics, immunotherapies, etanercept and olmesartan. Possible associations have been reported with other biologic agents, medications used for glycemic control, antihypertensives, cholinesterase inhibitors, potassium and iron supplements, with conflicting data regarding contraceptives/hormonal therapy and isotretinoin.

CONCLUSION

Physicians should be aware of the manifestations of drug-induced enteropathy as early recognition can lead to prompt discontinuation of the offending therapy and, therefore, a reduced risk of future complications.

Effects of Colchicine on NSAID-Induced Severe Small Intestinal Damage: A Pilot Study

BACKGROUND

We previously reported that nonsteroidal anti-inflammatory drugs (NSAIDs) induced small intestinal damage through nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome-dependent interleukin-1β secretion in mice. Our further study demonstrated that colchicine, a therapeutic agent for gout, significantly suppressed NSAID-induced small intestinal damage by inhibiting NLRP3 inflammasome activation in mice. However, clinical efficacy of colchicine for NSAID-induced small intestinal damage has not been established.

OBJECTIVES

We examined the clinical efficacy of colchicine in patients with NSAID-induced severe small intestinal damage as an animal-to-human translational research.

METHODS

This is a single-center, single-arm, prospective pilot study. From February 2017 to March 2019, we performed video capsule endoscopy (VCE) to screen 10 patients who took NSAIDs continuously for more than 3 months, and 7 of those with severe small intestinal damage were enrolled. Participants were treated with oral colchicine 0.5 mg twice daily for 8 weeks and thereafter followed up with blood tests and VCE.

RESULTS

After 8 weeks of colchicine treatment, complete healing was achieved in 4 patients (57.1%), and the median number of small erosions decreased significantly from 7.0 (range, 5.0-10.5) to 0.0 (range, 0.0-2.3) (p = 0.031). One patient withdrew due to diarrhea, and 5 patients revealed slightly elevated liver enzymes during the study. No other adverse events including changes in blood tests and clinical symptoms were observed.

CONCLUSIONS

Colchicine treatment achieved a high rate of complete healing in patients with NSAID-induced severe small intestinal damage.

NSAIDs, gastrointestinal toxicity and inflammatory bowel disease

Non-steroidal antiinflammatory drugs (NSAIDs) are currently one of the most widely used drugs. The use of NSAIDs is associated with gastrointestinal toxicity, affecting both upper gastrointestinal tract (peptic ulcer disease) and lower gastrointestinal tract (NSAID-induced enteropathy). NSAIDs use has been associated with an increased risk of clinical relapse in inflammatory bowel disease patients. In this article, we review the upper and lower gastrointestinal toxicity of NSAIDs, with a focus on the risks and specific data of these drugs in inflammatory bowel disease patients, giving recommendations for its appropriate use in the clinical practice. Although evidence is scarce, short-term use of NSAIDs appears to be safe, and the data available suggest that selective COX-2 inhibitors are the safer option. NSAIDs should be avoided as long-term treatment or with high doses, especially in patients with active inflammation.

Effects of phenylbutazone alone or in combination with a nutritional therapeutic on gastric ulcers, intestinal permeability, and fecal microbiota in horses

Background

Gastrointestinal (GI) injury and dysbiosis are adverse events associated with nonsteroidal anti‐inflammatory drug (NSAID) use in horses. Phenylbutazone has been shown to alter GI barrier function both in vitro and ex vivo, but its effects on barrier function have not been assessed in vivo. In addition, the ability of nutritional therapeutics to prevent these changes is not known.

Objective

Our objectives were to determine whether (a) phenylbutazone affected barrier function in vivo and (b) if phenylbutazone‐induced GI injury could be ameliorated by the use of a nutritional therapeutic.

Animals

Thirty healthy horses were randomly assigned to 3 groups (n = 10 per group): control, phenylbutazone, or phenylbutazone plus nutritional therapeutic.

Methods

This study was conducted as a blinded, randomized block design. All horses were managed identically throughout the study period. Samples were collected throughout the study period to monitor fecal microbiota changes and gastric ulcers before and after treatment. Quantification of the bacterial 16S rRNA gene in blood was used as a marker of intestinal permeability.

Results

Phenylbutazone increased amounts of bacterial 16S rDNA in circulation 3.02‐fold (95% confidence interval [CI], 0.1.89‐4.17), increased gastric ulceration score by a mean of 1.1 grade (P = .02), and induced specific changes in the microbiota, including loss of Pseudobutyrivibrio of family Lachnospiraceae. These changes were attenuated by nutritional treatment.

Conclusions and Clinical Importance

Collectively, these findings suggest that phenylbutazone induces GI injury, including impaired barrier function, and that nutritional treatment could attenuate these changes.

Gut Microbiota in NSAID Enteropathy: New Insights From Inside

As a class of the commonly used drugs in clinical practice, non-steroidal anti-inflammatory drugs (NSAIDs) can cause a series of adverse events including gastrointestinal injuries. Besides upper gastrointestinal injuries, NSAID enteropathy also attracts attention with the introduction of capsule endoscopy and double balloon enteroscopy. However, the pathogenesis of NSAID enteropathy remains to be entirely clarified. Growing evidence from basic and clinical studies presents that gut microbiota is a critical factor in NSAID enteropathy progress. We have reviewed the recent data about the interplay between gut microbiota dysbiosis and NSAID enteropathy. The chronic medication of NSAIDs could change the composition of the intestinal bacteria and aggravate bile acids cytotoxicity. Meanwhile, NSAIDs impair the intestinal barrier by inhibiting cyclooxygenase and destroying mitochondria. Subsequently, intestinal bacteria translocate into the mucosa, and then lipopolysaccharide released from gut microbiota combines to Toll-like receptor 4 and induce excessive production of nitric oxide and pro-inflammatory cytokines. Intestinal injuries present in the condition of intestinal inflammation and oxidative stress. In this paper, we also have reviewed the possible strategies of regulating gut microbiota for the management of NSAID enteropathy, including antibiotics, probiotics, prebiotics, mucosal protective agents, and fecal microbiota transplant, and we emphasized the adverse effects of proton pump inhibitors on NSAID enteropathy. Therefore, this review will provide new insights into a better understanding of gut microbiota in NSAID enteropathy.

Current knowledge on non-steroidal anti-inflammatory drug-induced small-bowel damage: a comprehensive review

Recent advances in small-bowel endoscopy such as capsule endoscopy have shown that non-steroidal anti-inflammatory drugs (NSAIDs) frequently damage the small intestine, with the prevalence rate of mucosal breaks of around 50% in chronic users. A significant proportion of patients with NSAIDs-induced enteropathy are asymptomatic, but some patients develop symptomatic or complicated ulcers that need therapeutic intervention. Both inhibition of prostaglandins due to the inhibition of cyclooxygenases and mitochondrial dysfunction secondary to the topical effect of NSAIDs play a crucial role in the early process of injury. As a result, the intestinal barrier function is impaired, which allows enterobacteria to invade the mucosa. Gram-negative bacteria and endogenous molecules coordinate to trigger inflammatory cascades via Toll-like receptor 4 to induce excessive expression of cytokines such as tumor necrosis factor-α and to activate NLRP3 inflammasome, a multiprotein complex that processes pro-interleukin-1β into its mature form. Finally, neutrophils accumulate in the mucosa, resulting in intestinal ulceration. Currently, misoprostol is the only drug that has a proven beneficial effect on bleeding small intestinal ulcers induced by NSAIDs or low-dose aspirin, but its protection is insufficient. Therefore, the efficacy of the combination of misoprostol with other drugs, especially those targeting the innate immune system, should be assessed in the next step.

Dynamics of concomitant therapy in children with juvenile idiopathic arthritis treated with etanercept and methotrexate

BACKGROUND

Both the steroid- and NSAID-sparing effects of biologics in juvenile idiopathic arthritis (JIA) treatment are key aspects of the dynamics of patient's condition. The proper selection of biologics enables maximum treatment effectiveness and reduction of the dosage of concomitant therapy. Our aim was to study the dynamics of concomitant therapy during etanercept (ETA) and methotrexate (MTX) treatment in patients with JIA.

METHODS

This analysis included 215 JIA patients (63.3% females) showing sufficient response to main therapy. One hundred patients received MTX as main therapy, 24 received ETA monotherapy, and 91 received ETA þ MTX combination therapy. The dynamics of concomitant therapy were analyzed after 1 month, every 3 months during the first year, and every 6 months during the long-term follow-up (up to 5 years).

RESULTS

At the baseline, 24 (11.2%) patients received concomitant oral glucocorticoids (orGCs) and NSAIDs; the remaining 191 (88.8%) patients were treated with concomitant NSAIDs only. Within 1-year treatment, NSAIDs were discontinued in 162 (75.3%) patients. There were no significant differences in the dynamics of withdrawal of NSAIDs in patients who received and did not receive concomitant MTX. However, the percentage of treatment discontinuation in the MTX group was significantly lower compared to the other two groups (p < 0.001). Oral GCs were discontinued completely in 4 children (16.7%), and the dose of oral GCs was reduced in another 4 patients (16.7%). By the end of the follow-up period, 44 of 115 patients (38.3%) treated with ETA in combination with any concomitant therapy could switch to ETA monotherapy.

CONCLUSION

Therapy with ETA makes it possible to reduce the dosage or completely discontinue most concomitant medications (orGCs, NSAIDs, MTX) in a significant percentage of patients. This reduces the risk of development of NSAID- and GC-induced pathological conditions, while the effectiveness of therapy of the underlying condition remains high.

Long-term outcome of endoscopic submucosal dissection for early gastric cancer in patients with severe comorbidities: a comparative propensity score analysis

BACKGROUND

Recently, endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) has been performed on patients with severe comorbidities because it is less invasive, although little is known regarding long-term outcomes. This study aimed to assess the long-term outcomes of ESD for patients with severe and non-severe comorbidities.

METHODS

We enrolled 1081 patients who underwent ESD for EGC between February 2004 and June 2013. Based on the American Society of Anesthesiologists Physical Status (ASA-PS) classification, we defined patients with severe and non-severe comorbidities as ASA-PS 3 and 1/2, respectively. We retrospectively compared the overall survival, risk factors for mortality, and adverse events between these two groups using propensity score matching and inverse probability of treatment weighting.

RESULTS

A total of 488 patients met the eligibility criteria. After matching, the ASA-PS 3 group showed a significantly shorter survival than the ASA-PS 1/2 group (5-year overall survival rate, 79.1 vs. 87.7%; p < 0.01). In addition, only the ASA-PS 3 group had a significant risk factor for mortality using both the Cox analysis [hazard ratio (HR), 2.56; 95% confidence interval (CI) 1.18-5.52; p = 0.02] and the IPTW method (HR, 3.14; 95% CI 1.91-5.14; p < 0.01). There was no significant difference in adverse events after matching between the two groups (p = 0.21).

CONCLUSIONS

The long-term outcome of gastric ESD for patients with severe comorbidities was worse than for those with non-severe comorbidities. Further studies will be necessary to determine if ESD is truly warranted in these patients.

Network pharmacology-based identification of protective mechanism of Panax Notoginseng Saponins on aspirin induced gastrointestinal injury

BACKGROUND & AIMS

Aspirin is the first line therapy for cardiovascular and cerebrovascular diseases and is widely used. However aspirin-induced gastrointestinal injury is one of its most common side effect which limits long-term use. Panax Notoginseng Saponins(PNS) which is also used to prevent thrombus may alleviate this side effect according to previous clinical evidences. Owing to the complexity of drug combination, the protective mechanism of PNS on aspirin-induced gastrointestinal injury remains unclear. Therefore, a network pharmacology-based strategy was proposed in this study to address this problem.

METHODS

A network pharmacology approach comprising multiple components, candidate targets of each component, known therapeutic targets, network analysis has been used in this study. Also, we establish aspirin-induced gastrointestinal injury model by the oral administration of aspirin (0.5 g/kg body weight) to verify the predicted targets from network pharmacology. All rats was randomly allocated to control groups (n = 6),aspirin groups (n = 6)and aspirin + PNS groups (n = 6) and conducted H&E staining and ELISA for VEGFA.

RESULTS

The comprehensive systematic approach was successfully to identify 5 compounds and 154 candidate targets in PNS and 479 candidate targets in aspirin. After network establishment and analysis, 27 potential targets hit by PNS, aspirin and 6 kind of gastrointestinal diseases were found. The experiments results indicated that aspirin group has visible inflammation and lesions while aspirin + PNS group have not. The higher expression of VEGFA in aspirin + PNS group verified the predicted potential protective targets of PNS.

CONCLUSIONS

PNS may have protective function for aspirin-induced gastrointestinal injury through increasing VEGFA expression. Network pharmacology strategy may provide a forceful tool for exploring the mechanism of herb medicine and discovering novel bioactive ingredients.

Does discontinuation of antithrombotics affect the diagnostic yield of small bowel capsule endoscopy in patients demonstrating obscure gastrointestinal bleeding?

A large proportion of patients demonstrating obscure gastrointestinal bleeding (OGIB) are antithrombotic users and need to undergo small bowel capsule endoscopy (SBCE). We examined the effect of discontinuation of antithrombotics on the diagnostic yield of SBCE. Additionally, we assessed predictive factors associated with positive SBCE findings. Our study included 130 patients using antithrombotics who underwent SBCE for overt OGIB. The primary endpoint was the difference in the rate of positive SBCE findings between patients who continued and those who discontinued antithrombotics. Secondary endpoints were to investigate the effect of discontinuation of antithrombotics using a propensity score analysis, and to assess predictive factors associated with a positive SBCE. Among the 73 patients who continued use of antithrombotics, 36 (49.3%) patients demonstrated positive findings, while among the 57 patients who discontinued antithrombotics, 35 (61.4%) patients showed positive findings. Rates of positive SBCE findings didn't differ between the two groups. After we performed propensity score matching, discontinuation didn't affect the rate of positive SBCE findings. The lowest hemoglobin level was the only independent predictive factor associated with positive SBCE findings. In conclusion, discontinuation of antithrombotic therapy didn't affect the diagnostic yield of SBCE in patients presenting with overt OGIB.

Isoliquiritigenin Ameliorates Indomethacin-Induced Small Intestinal Damage by Inhibiting NOD-Like Receptor Family, Pyrin Domain-Containing 3 Inflammasome Activation

Activation of the NOD-Like Receptor Family, Pyrin Domain-Containing 3 (NLRP3) inflammasome, which consists of NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), and pro-caspase-1, triggers pro-caspase-1 cleavage promoting the processing of pro-interleukin (IL)-1β into mature IL-1β, which is critical for the development of non-steroidal anti-inflammatory drug (NSAID)-induced enteropathy. We investigated the effects of isoliquiritigenin, a flavonoid derived from the roots of Glycyrrhiza species, on NSAID-induced small intestinal damage and the inflammasome activation. To induce enteropathy, mice were administered indomethacin by gavage with or without isoliquiritigenin pretreatment. Some mice received an intraperitoneal injection of recombinant murine IL-1β in addition to isoliquiritigenin and indomethacin. Indomethacin induced small intestinal damage and increased protein levels of cleaved caspase-1 and mature IL-1β in the small intestine. Treatment with 7.5 and 75 mg/kg isoliquiritigenin inhibited indomethacin-induced small intestinal damage by 40 and 56%, respectively. Isoliquiritigenin also inhibited the indomethacin-induced increase in cleaved caspase-1 and mature IL-1β protein levels, whereas it did not affect the mRNA expression of NLRP3, ASC, caspase-1, and IL-1β. Protection against intestinal damage in isoliquiritigenin-treated mice was completely abolished with exogenous IL-1β. NLRP3-/- and caspase-1-/- mice exhibited resistance to intestinal damage, and isoliquiritigenin treatment failed to inhibit the damage in NLRP3-/- and caspase-1-/- mice. Isoliquiritigenin prevents NSAID-induced small intestinal damage by inhibiting NLRP3 inflammasome activation.

Clinical factors associated with positive capsule endoscopy findings in patients with obscure gastrointestinal bleeding: a single-center study

BACKGROUND

Capsule endoscopy (CE) is a useful tool for patients with obscure gastrointestinal bleeding (OGIB), but positive finding rate differs among trials, which may be attributable to the difference in patients' background.

OBJECTIVES

To evaluate the predictive factors associated with positive findings on CE.

METHODS

Consecutive patients with OGIB who underwent CE between March 2004 and May 2015 at a single university hospital were enrolled. Patients' clinical factors and CE data were reviewed retrospectively, and we evaluated the relationship between clinical factors and positive findings by univariate and multivariate logistic regression analyses.

RESULTS

Five hundred and seventy-eight patients were included in the analysis. Positive CE findings were obtained in 284 patients (49.1%). In multivariate analysis, low hemoglobin level (odds ratio (OR), 1.142 per 1 g/dL decrease; p < .001), Charlson comorbidity index (CCI) score (OR, 1.170 per 1 point increase; p = .002), and non-steroidal anti-inflammatory drug (NSAID) use (OR, 1.640; p = .044) were associated with an increased prevalence of positive findings. As for components of CCI, malignant tumor (OR, 1.839; p = .017) was associated with the positive findings.

CONCLUSIONS

OGIB patient with a low-hemoglobin level, complex and severe comorbidities, and NSAID use should receive CE.

The non-invasive exfoliated transcriptome (exfoliome) reflects the tissue-level transcriptome in a mouse model of NSAID enteropathy

Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most frequently used classes of medications in the world, yet they induce an enteropathy that is associated with high morbidity and mortality. A major limitation to better understanding the pathophysiology and diagnosis of this enteropathy is the difficulty of obtaining information about the primary site of injury, namely the distal small intestine. We investigated the utility of using mRNA from exfoliated cells in stool as a means to surveil the distal small intestine in a murine model of NSAID enteropathy. Specifically, we performed RNA-Seq on exfoliated cells found in feces and compared these data to RNA-Seq from both the small intestinal mucosa and colonic mucosa of healthy control mice or those exhibiting NSAID-induced enteropathy. Global gene expression analysis, data intersection, pathway analysis, and computational approaches including linear discriminant analysis (LDA) and sparse canonical correlation analysis (CCA) were used to assess the inter-relatedness of tissue (invasive) and stool (noninvasive) datasets. These analyses revealed that the exfoliated cell transcriptome closely mirrored the transcriptome of the small intestinal mucosa. Thus, the exfoliome may serve as a non-invasive means of detecting and monitoring NSAID enteropathy (and possibly other gastrointestinal mucosal inflammatory diseases).

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.

Different effects of anti-TNF-alpha biologic drugs on the small bowel macroscopic inflammation in patients with ankylosing spondylitis

BACKGROUND & AIMS

Considering the ability of anti-TNF alpha drugs to lower the burden intestinal inflammation in patients with inflammatory bowel disease (IBD), and the similarity between IBD and ankylosing spondylitis (AS) regarding inflammatory intestinal involvement, we aimed to investigate the impact of anti-TNF alpha biologic therapy on subclinical intestinal inflammation in AS patients.

METHODS

Between January 2008 and December 2013, 38 AS patients and 23 controls were enrolled in the study and investigated with small bowel videocapsule endoscopy examination and ileocolonoscopy. Each tertile of the small bowel (proximal, mid and distal) was assessed by calculating the Lewis score based on the image stream.

RESULTS

The Lewis scores were significantly higher in the AS group compared to controls (580.9 ± 818 vs. 81 ± 121, p<0.001). 16 patients (42.1%) were on anti-TNF alpha therapy (Adalimumab (n = 5), Infliximab (n = 5) or Etanercept (n = 6)).31.3% of them used NSAIDs simultaneously, compared with 77.3% of the other patients (p<0.01). Their Lewis scores were lower compared to the other patients for the entire small bowel (306 ± 164 vs. 790 ± 1038, p = 0.015), its proximal and distal tertiles (238 ± 154 vs. 560 ± 543, p = 0.021, and 140 ± 189 vs. 300 ± 220, p = 0.027, respectively). The Lewis score was also lower in patients receiving Adalimumab/Infliximab compared to those on Etanercept for the entire bowel and its distal tertile (262 ± 165 vs. 380 ± 148, p = 0.069 and 62 ± 101 vs. 273 ± 236, p = 0.060, respectively).

CONCLUSION

Anti-TNF alpha therapy in patients with AS reduces the subclinical intestinal inflammation, but the magnitude seems to depend upon the class anti-TNF alpha agent used (Clinical Trials. gov NCT00768950).

Long-term prognosis of expanded-indication differentiated-type early gastric cancer treated with endoscopic submucosal dissection or surgery using propensity score analysis

BACKGROUND AND AIMS

Although endoscopic submucosal dissection (ESD) for expanded-indication lesions of differentiated-type early gastric cancer (EGC) has been widely accepted, no prospective randomized study has been conducted on this subject. This study aimed to evaluate the long-term outcomes of ESD and surgery for expanded-indication lesions of differentiated-type EGC.

METHODS

Between 1997 and 2012, 1500 consecutive patients with EGC were treated in Osaka City University Hospital. Using propensity score matching and inverse probability of treatment weighting (IPTW), we retrospectively evaluated the long-term outcomes, risk factors for mortality, and adverse events for patients with expanded-indication lesions of differentiated-type EGC who underwent ESD or surgical treatments.

RESULTS

A total of 308 patients with expanded-indication lesions of differentiated-type EGC confirmed by pathologic examination after ESD or surgery met the eligibility criteria. After matching, the 5-year overall survival rate was higher in the ESD group than in the surgery group (97.1% vs 85.8%; P = .01). We also found that surgery was significantly associated with mortality using both the IPTW method (hazard ratio [HR], 10.89; 95% confidence interval [CI], 1.37-86.6; P < .01), and Cox analysis (HR, 8.60; 95% CI, 1.11-66.52; P = .04) after matching. Significantly fewer adverse events were associated with ESD than with surgery (6.8% vs 28.4%; P < .01). No cause-specific mortality was observed in either group.

CONCLUSIONS

Our results indicate that ESD might be an alternative treatment modality for expanded-indication lesions of differentiated-type EGC.

Investigation of the effect of phlomisoside F on complete Freund's adjuvant-induced arthritis

Phlomis younghusbandii Mukerjee (Labiatae) has been reported to be effective in the treatment of rheumatoid arthritis (RA). In the present study, the anti-inflammatory and anti-arthritic effects of phlomisoside F (PF), isolated from P. younghusbandii Mukerjee (Labiatae), were investigated in male Wistar rats subjected to carrageen-induced paw edema and complete Freund's adjuvant (CFA)-induced arthritis. Arthritis scores were evaluated by a 5-point ordinal scale (scores 0-4). Expression levels of TNF-α, IL-1β, IL-6, IL-10, COX-2 and 5-LOX were determined via ELISA and western blot assays. Subsequent to establishing the edema and arthritis models, oral administration of PF (5, 10 and 20 mg/kg) significantly inhibited mean edema rate, compared with the control group in carrageenan-induced paw edema assay. In addition, administration of PF (5, 10 and 20 mg/kg/day) for 28 days markedly exhibited an anti-arthritic activity by offsetting the body weight loss, inhibiting the paw edema, reducing the arthritis scores and the indices of thymus and spleen, inhibiting the expression levels of TNF-α, IL-1β, IL-6, COX-2 and 5-LOX, and increasing the expression of IL-10, when compared with the respective control group in CFA-induced arthritis assay. In conclusion, PF is a valuable anti-arthritic constituent of P. younghusbandii, and the present study results suggest that this herb may be used in the treatment of RA.

Colchicine prevents NSAID-induced small intestinal injury by inhibiting activation of the NLRP3 inflammasome

The inflammasome is a large, multiprotein complex that consists of a nucleotide-binding oligomerization domain-like receptor (NLR), an apoptosis-associated speck-like protein containing a caspase recruitment domain, and pro-caspase-1. Activation of the inflammasome results in cleavage of pro-caspase-1 into cleaved caspase-1, which promotes the processing of pro-interleukin (IL)-1β into mature IL-1β. We investigated the effects of colchicine on non-steroidal anti-inflammatory drug (NSAID)-induced small intestinal injury and activation of the NLR family pyrin domain-containing 3 (NLRP3) inflammasome. Colchicine treatment inhibited indomethacin-induced small intestinal injury by 86% (1 mg/kg) and 94% (3 mg/kg) as indicated by the lesion index 24 h after indomethacin administration. Colchicine inhibited the protein expression of cleaved caspase-1 and mature IL-1β, without affecting the mRNA expression of NLRP3 and IL-1β. Although treatment with recombinant IL-1β (0.1 μg/kg) did not change the severity of small intestinal damage, the preventive effects of colchicine were abolished by supplementation with the same dose of recombinant IL-1β. Indomethacin-induced small intestinal damage was reduced by 77%, as determined by the lesion index in NLRP3^−/− mice, and colchicine treatment failed to inhibit small intestinal damage in NLRP3^−/− mice. These results demonstrate that colchicine prevents NSAID-induced small intestinal injury by inhibiting activation of the NLRP3 inflammasome.

Clinical importance of nonsteroidal anti-inflammatory drug enteropathy: the relevance of tumor necrosis factor as a promising target

The pathogenesis of nonsteroidal anti-inflammatory drug (NSAID) enteropathy is still unclear, and consequently, there is no approved therapeutic strategy for ameliorating such damage. On the other hand, molecular treatment strategies targeting tumor necrosis factor (TNF) exerts beneficial effects on NSAID-induced intestinal lesions in rodents and rheumatoid arthritis patients. Thus, TNF appears to be a potential therapeutic target for both the prevention and treatment of NSAID enteropathy. However, the causative relationship between TNF and NSAID enteropathy is largely unknown. Currently approved anti-TNF agents are highly expensive and exhibit numerous side effects. Hence, in this review, the pivotal role of TNF in NSAID enteropathy has been summarized and plant-derived polyphenols have been suggested as useful alternative anti-TNF agents because of their ability to suppress TNF activated inflammatory pathways both in vitro and in vivo.

Mechanisms of NLRP3 inflammasome activation and its role in NSAID-induced enteropathy

Nonsteroidal anti-inflammatory drugs (NSAIDs) induce cytokines, including tumor necrosis factor-α and interleukins (ILs), in the small intestine via a Toll-like receptor 4 (TLR4)-dependent pathway, leading to intestinal ulceration. Activation of the inflammasome promotes pro-caspase-1 cleavage, leading to pro-IL-1β maturation. We examined the role of NLRP3 inflammasome in NSAID-induced enteropathy. Small intestinal damage developed 3 h after indomethacin administration, accompanied by increases in IL-1β and NLRP3 mRNA expression and mature caspase-1 and IL-1β levels. In vivo blocking of IL-1β using neutralizing antibodies attenuated indomethacin-induced damage, whereas exogenous IL-1β aggravated it. NLRP3(-/-) and caspase-1(-/-) mice exhibited resistance to the damage with reduction of mature IL-1β production. This resistance was abolished by exogenous IL-1β. TLR4 deficiency prevented intestinal damage and inhibited upregulation of NLRP3 and IL-1β mRNAs and maturation of pro-caspase-1 and pro-IL-1β, whereas TLR4 activation by its agonists exerted opposite effects. Apyrase, an adenosine triphosphate (ATP) scavenger, or Brilliant Blue G, a purinergic P2X7 receptor antagonist, inhibited the damage as well as caspase-1 activation and IL-1β processing, despite there being sufficient amounts of pro-IL-1β and NLRP3. These results suggest that NLRP3 inflammasome-derived IL-1β plays a crucial role in NSAID-induced enteropathy and that both TLR4- and P2X7-dependent pathways are required for NLRP3 inflammasome activation.

A multicenter, randomized, double-blind, placebo-controlled trial of high-dose rebamipide treatment for low-dose aspirin-induced moderate-to-severe small intestinal damage

BACKGROUND

Low-dose aspirin (LDA) frequently causes small bowel injury. While some drugs have been reported to be effective in treating LDA-induced small intestinal damage, most studies did not exclude patients with mild damage thought to be clinically insignificant.

AIM

We conducted a multicenter, randomized, double-blind, placebo-controlled trial to assess the efficacy of a high dose of rebamipide, a gastroprotective drug, for LDA-induced moderate-to-severe enteropathy.

METHODS

We enrolled patients who received 100 mg of enteric-coated aspirin daily for more than 3 months and were found to have more than 3 mucosal breaks (i.e., erosions or ulcers) in the small intestine by capsule endoscopy. Eligible patients were assigned to receive either rebamipide 300 mg (triple dose) 3 times daily or placebo for 8 weeks in a 2:1 ratio. Capsule endoscopy was then repeated. The primary endpoint was the change in the number of mucosal breaks from baseline to 8 weeks. Secondary endpoints included the complete healing of mucosal breaks at 8 weeks and the change in Lewis score (an endoscopic score assessing damage severity) from baseline to 8 weeks.

RESULTS

The study was completed by 38 patients (rebamipide group: n = 25, placebo group: n = 13). After 8 weeks of treatment, rebamipide, but not placebo, significantly decreased the number of mucosal breaks (p = 0.046). While the difference was not significant (p = 0.13), the rate of complete mucosal break healing in the rebamipide group (32%, 8 of 25) tended to be higher than that in the placebo group (7.7%, 1 of 13). Rebamipide treatment significantly improved intestinal damage severity as assessed by the Lewis score (p = 0.02), whereas placebo did not. The triple dose of rebamipide was well tolerated.

CONCLUSIONS

High-dose rebamipide is effective for the treatment of LDA-induced moderate-to-severe enteropathy.

TRIAL REGISTRATION

UMIN Clinical Trials Registry UMIN000003463.

Amelioration of small bowel injury by switching from nonselective nonsteroidal anti-inflammatory drugs to celecoxib in rheumatoid arthritis patients: a pilot study

BACKGROUND/AIMS

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used in patients with rheumatoid arthritis (RA) but have several side effects including mucosal damage in the small intestine. We aimed to evaluate whether the small bowel injury is ameliorated by switching from nonselective NSAIDs to celecoxib in patients with RA.

METHODS

Sixteen patients with RA who were treated with nonselective NSAIDs were enrolled in this study. Nonselective NSAIDs were converted to celecoxib for 12 weeks. Capsule endoscopy was performed before and after treatment with celecoxib. Videos were screened by gastroenterologists blinded to the patients' treatment.

RESULTS

Before the administration of celecoxib, reddened folds, denuded areas, petechiae/red spots and mucosal breaks were observed in 63, 63, 88 and 69% of the patients, respectively. In the 14 patients who completed this study, conversion to celecoxib significantly reduced the number of petechiae/red spots, the number of mucosal breaks, and Lewis scores. RA activity and cytokine levels in the peripheral blood were not significantly different before and after treatment with celecoxib.

CONCLUSIONS

The incidence of small bowel injury by nonselective NSAIDs is high in patients with RA. Conversion from nonselective NSAIDs to celecoxib can be useful for protecting patients with RA from small bowel injury.

The prevalence of adverse events associated with double-balloon enteroscopy from a single-centre dataset in Japan

BACKGROUND

There are few comprehensive reports detailing the prevalence of major adverse events associated with a double-balloon enteroscopy procedure.

METHODS

We retrospectively investigated the prevalence of major adverse events in 538 patients (262 males and 276 females; median age, 65 years; age range, 12-95 years) who underwent double-balloon enteroscopy at our Institution between April 2008 and October 2011.

RESULTS

Of the 17 adverse events recorded (3.2%), acute pancreatitis (n=5; 0.9%) occurred during both diagnostic (n=3) and therapeutic (n=2) anterograde double-balloon enteroscopy, and all of them were treated conservatively. For these cases, the average duration of the examination was 135 min, which was longer than for the other patients (97 min) (P=0.046). Intestinal bleeding (1.3%) was observed in 6 cases after endoscopic polypectomy and in 1 case following a biopsy procedure during a diagnostic double-balloon enteroscopy. The prevalence rates of intestinal perforation and other complications were 0.2% and 0.7%, respectively.

CONCLUSIONS

The rate of adverse events associated with double-balloon enteroscopy was high compared to that associated with conventional upper/lower gastrointestinal endoscopy (0.042%/0.078%). The occurrence of acute pancreatitis may be significantly dependent on the duration of double-balloon enteroscopy examination.

Mouse models of hepatitis B and delta virus infection

Liver disease associated to persistent infection with the hepatitis B virus (HBV) continues to be a major health problem of global impact. Therapeutic regimens currently available can efficiently suppress HBV replication; however, the unique replication strategies employed by HBV permit the virus to persist within the infected hepatocytes. As a consequence, relapse of viral activity is commonly observed after cessation of treatment with polymerase inhibitors. Among the HBV chronically infected patients, more than 15million patients are estimated to be co-infected with the hepatitis delta virus (HDV), a defective satellite virus that needs the HBV envelope for propagation. No specific drugs are currently available against HDV, while nucleos(t)ide analogs are not effective against HDV replication. Since chronic HBV/HDV co-infection leads to the most severe form of chronic viral hepatitis in men, a better understanding of the molecular mechanisms of HDV-mediated pathogenesis and the development of improved therapeutic approaches is urgently needed. The obvious limitations imposed by the use of great apes and the paucity of robust experimental models of HBV infection have hindered progresses in understanding the complex network of virus-host interactions that are established in the course of HBV and HDV infections. This review focuses on summarizing recent advances obtained with well-established and more innovative experimental mouse models, giving emphasis on the strength of infection systems based on the reconstitution of the murine liver with human hepatocytes, as tools for elucidating the whole life cycle of HBV and HDV, as well as for studies on interactions with the infected human hepatocytes and for preclinical drug evaluation.