Histologic Diagnosis of Inflammatory Bowel Diseases

The use of vitamin D for patients with inflammatory bowel diseases

As vitamin D (VD) plays an essential role in inflammatory bowel diseases (IBD), this systematic review aimed to update the participation of this vitamin in the prevention or remission of these diseases. This review has included studies in MEDLINE-PubMed, EMBASE, and Cochrane databases. The authors have followed PRISMA (Preferred Reporting Items for a Systematic Review and Meta-analysis) guidelines. According to the inclusion and exclusion criteria, twenty-two randomized clinical trials were selected. In total, 1,209 patients were included in this systematic review: 1034 received only VD and 175 received VD in combination with calcium. The average doses of VD supplementation were from oral 400 IU daily to 10,000 IU per kilogram of body weight. Single injection of 300,000 IU of VD was also used. Several studies have shown the crucial role that VD plays in the therapeutic approach of IBD due to its effects on the immune system. It effectively decreased inflammatory cytokines such as TNF-α and IFN-γ (p<0.05) and provided a reduction in disease activity assessed through different scores such as Crohn's Disease Activity Index (CDAI) (p<0.05) and Ulcerative Colitis Disease Activity Index (UCDAI) (p<0.05). Unfortunately, the available clinical trials are not standardized for of doses and routes of administration. Existing meta-analyses are biased because they compare studies using different doses or treatments in combination with different drugs or supplements such as calcium. Even though VD has crucial effects on inflammatory processes, there is still a need for standardized studies to establish how the supplementation should be performed and the doses to be administered.

Mucosal Architectural Change is an Important Feature in Distinguishing Crohn's Disease From Others in Terminal Ileum Ulcer Biopsy

BACKGROUND

Besides Crohn's disease (CD), there are a variety of other causes that can also lead to ulcerations in the terminal ileum. The purpose of this study was to identify useful diagnostic features for CD when evaluating terminal ileum biopsies in patients with endoscopic finding of ulcers.

METHODS

Five hundred and seventy-one patients with endoscopic finding of ulcers were included in this retrospective study. Five main histological features were analysed, which were crypt irregularity, mucosal thickening, villous stromal widening (including villous atrophy), granulomas, and pseudopyloric gland metaplasia. Clinical and pathological features were determined by uni- and multivariable logistic regression. Then another independent cohort of 99 patients was established for verifying this nomogram.

RESULTS

The crypt irregularity, mucosal thickening, and villous stromal widening were combined to be considered as one new variable named mucosal architectural change which was an independent variable in diagnosing CD. We found that mucosal architectural change, age <40 years, the presence of granulomas, and the presence of pseudopyloric gland metaplasia were independent factors for the pathological diagnosis of CD. Then nomogram was developed, with receiver operating characteristic (ROC) curve (area under the ROC curve [AUC] = 0.927) in training sets, and ROC curve (AUC = 0.913) in validation sets.

CONCLUSIONS

We found mucosal architectural change is very helpful in distinguishing CD from non-CD patients. In the context of small biopsy which may lack full scope of changes, the model developed by combining these key features is valuable in predicting a diagnosis of CD, especially in younger patients (age <40 years).

Untargeted metabolomics identifies potential serum biomarkers associated with Crohn's disease

Crohn's disease (CD) is well characterized by chronic inflammation of the gastrointestinal tract. The diagnose of CD relays on the comprehensive evaluation of patient symptoms, laboratory examination, radiology, and endoscopy. There is lack of biomarkers or simple test for CD detection. Serum samples from healthy subjects (n = 16) and CD patients (n = 16) were collected and prepared for untargeted metabolomics analysis using the ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) method. The alterations of serum metabolites and the potential biomarkers were profiled by statistical analysis. And the associated metabolic pathway was analyzed based on Kyoto Encyclopedia of Genes and Genomes (KEGG) database. The performance of potential biomarkers was assessed by receiver operating characteristic (ROC) analysis. A complete separation between HS and CD groups was seen in OPLS-DA. A total of 108 and 131 significantly altered metabolites in positive and negative ion mode, respectively, were identified, and most of them belong to several pathways ranging from lipid metabolism to amino acid metabolism and energy homeostasis. KEGG analysis revealed that lipid metabolism enriched most significantly. Further, ceramide, phosphatidylethanolamine (PE), and taurochenodeoxycholic acid (TCDCA) presented the highest predictive accuracy of the patients with CD as analyzed by ROC. The current study demonstrated that lipid metabolism is mostly related to CD pathogenesis. Further investigations are indicated to examine the use of lipid-related metabolites of ceramide, PE, and TCDCA as potential biomarkers for CD diagnosis.

Quinic acid ameliorates ulcerative colitis in rats, through the inhibition of two TLR4-NF-κB and NF-κB-INOS-NO signaling pathways

OBJECTIVE

In this study, the therapeutic effect of quinic acid (QA), which has anti-inflammatory activity, was investigated on acetic acid-induced colitis in male Wistar rats.

METHODS

Ulcerative colitis (UC) was induced in rats by acetic acid intrarectally, and the protective effects of QA in 10, 30, 60, and 100 mg/kg doses were investigated. Rats were treated for 5 days and their colon tissues were dissected out at the end. Macroscopic and histopathological examinations were performed in colon tissues. Also, the expression of inflammatory and apoptotic genes, including TLR4, IL-1β, INOS, IL-6, TNF-α, NF-κB, Caspase-3, Caspase-8, Bax, and Bcl-2, was measured. Biochemistry indices, such as malondialdehyde (MDA) and nitrite oxide (NO) content, in addition to, total antioxidant capacity (TAC), superoxide dismutase (SOD), catalase (CAT), and enzymes activities were also assessed.

RESULTS

Colitis increased the levels of MDA and NO, and enhanced the inflammatory and apoptotic gene expressions, while reducing the SOD and CAT enzymes activity, and TAC levels in the colitis rats. Also, results showed that colitis was associated with the infiltration of inflammatory cells, epithelium damage, and edema in colon tissue. QA significantly ameliorated histopathological indices, oxidative stress, inflammation, and apoptosis in colitis rats.

CONCLUSION

QA ameliorated UC through the inhibition of two TLR4-NF-κB and NF-κB-INOS-NO signaling pathways, which results in the reduction of colitis complications, including oxidative stress, inflammation, apoptosis and histopathological injuries in rats. Therefore it can be concluded, that QA exerts its therapeutic effects through antiapoptotic, antioxidant, and anti-inflammatory properties.

Clostridioides difficile Toxin B Induced Senescence: A New Pathologic Player for Colorectal Cancer?

Clostridioides difficile (C. difficile) is responsible for a high percentage of gastrointestinal infections and its pathological activity is due to toxins A and B. C. difficile infection (CDI) is increasing worldwide due to the unstoppable spread of C. difficile in the anthropized environment and the progressive human colonization. The ability of C. difficile toxin B to induce senescent cells and the direct correlation between CDI, irritable bowel syndrome (IBS), and inflammatory bowel diseases (IBD) could cause an accumulation of senescent cells with important functional consequences. Furthermore, these senescent cells characterized by long survival could push pre-neoplastic cells originating in the colon towards the complete neoplastic transformation in colorectal cancer (CRC) by the senescence-associated secretory phenotype (SASP). Pre-neoplastic cells could appear as a result of various pro-carcinogenic events, among which, are infections with bacteria that produce genotoxins that generate cells with high genetic instability. Therefore, subjects who develop IBS and/or IBD after CDI should be monitored, especially if they then have further CDI relapses, waiting for the availability of senolytic and anti-SASP therapies to resolve the pro-carcinogenic risk due to accumulation of senescent cells after CDI followed by IBS and/or IBD.

Hypericumsampsonii attenuates inflammation in mice with ulcerative colitis via regulation of PDE4/PKA/CREB signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Hypericum sampsonii Hance (Yuanbaocao), a traditional herbal medicine with various pharmacological properties, is traditionally used to treat diarrhea and enteritis in China for hundreds of years. Investigations have uncovered its anti-inflammatory effects and corresponding bioactive constituents in H. sampsonii, however, the mechanisms of action for the treatment of enteritis are still unclear.

AIMS OF THE STUDY

This study aims to investigate the therapeutic effects and molecular mechanisms of H. sampsonii in a dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) mice model.

MATERIALS AND METHODS

The major ingredients of the ethyl acetate extract (HS) in H. sampsonii were analyzed by UPLC-QTOF-MS. The inflammatory state of UC mice was caused by 3% DSS once daily for seven days. During DSS treatment, the mice in the positive drug group and the other three groups were orally administered 5-ASA (positive control) or HS daily. After treatment with HS or 5-ASA for a week, colonic pathological observation and the molecular biological index were performed for therapeutic evaluation, including visual inspection in the length and weight of colons and spleens, pathological morphology by hematoxylin and eosin (HE) staining, determination of oxidative markers, inflammatory cytokines and tumor necrosis factor-alpha (TNF-α) levels in colonic tissues as well as spleen index. Gene expression levels of inflammatory cytokines, antioxidant enzymes and PDE4 were detected using kits and PCR, while the expression of colonic tight junction proteins and relative signals of PKA/CREB signaling pathway were analyzed by Western blot.

RESULTS

The main components in HS were found to be polycyclic polyprenylated acylphloroglucinols (PPAPs). HS distinctly alleviated DSS-stimulated UC-like lesions symptoms as evidenced by a significant recovery from body weight, colon lengths, and histological injuries of colons. HS reduced the accumulation of pro-inflammatory cytokines and improved the mRNA level of IL-10. Simultaneously, the colonic mRNA expression levels of IL-1β, IL-17, iNOS and COX-2 were all significantly suppressed by HS in a dose-dependent manner. Furthermore, HS restored the protein expression of tight junction-associated protein (ZO-1 and occluding). Besides, HS significantly inhibited the protein level of PDE4 and decreased the expressions of PKA and phosphorylated CREB.

CONCLUSION

This is the first work about main composition and anti-UC effect of Hypericum sampsonii Hance. For the first time, this study reveals HS is not toxic in a single dose and exert significantly protective effect in DSS-colitis mice. The underlying mechanisms may involve the improvement to inflammatory status, the protection for intestinal barrier function, the inhibition of PDE4, and the activation of PKA/CREB signaling pathway. This study provided an experimental basis for the traditional application of H. sampsonii Hance in the treatment of diarrhea and dysentery.

Evidence-based pathogenesis and treatment of ulcerative colitis: A causal role for colonic epithelial hydrogen peroxide

In this comprehensive evidence-based analysis of ulcerative colitis (UC), a causal role is identified for colonic epithelial hydrogen peroxide (H₂O₂) in both the pathogenesis and relapse of this debilitating inflammatory bowel disease. Studies have shown that H₂O₂ production is significantly increased in the non-inflamed colonic epithelium of individuals with UC. H₂O₂ is a powerful neutrophilic chemotactic agent that can diffuse through colonic epithelial cell membranes creating an interstitial chemotactic molecular “trail” that attracts adjacent intravascular neutrophils into the colonic epithelium leading to mucosal inflammation and UC. A novel therapy aimed at removing the inappropriate H₂O₂ mediated chemotactic signal has been highly effective in achieving complete histologic resolution of colitis in patients experiencing refractory disease with at least one (biopsy-proven) histologic remission lasting 14 years to date. The evidence implies that therapeutic intervention to prevent the re-establishment of a pathologic H₂O₂ mediated chemotactic signaling gradient will indefinitely preclude neutrophilic migration into the colonic epithelium constituting a functional cure for this disease. Cumulative data indicate that individuals with UC have normal immune systems and current treatment guidelines calling for the suppression of the immune response based on the belief that UC is caused by an underlying immune dysfunction are not supported by the evidence and may cause serious adverse effects. It is the aim of this paper to present experimental and clinical evidence that identifies H₂O₂ produced by the colonic epithelium as the causal agent in the pathogenesis of UC. A detailed explanation of a novel therapeutic intervention to normalize colonic H₂O₂, its rationale, components, and formulation is also provided.