How achievable are STRIDE-II treatment targets in real-world practice and do they predict long-term treatment outcomes?

Objective: The second iteration of the Selecting Therapeutic Targets in Inflammatory Bowel Disease (STRIDE-II) initiative recommends use of the Simple Endoscopic Score for Crohn's disease (SES-CD) as a treatment target for patients with CD. We aimed to assess whether the STRIDE-II endoscopic endpoints are achievable and whether the degree of mucosal healing (MH) affects long-term outcomes. Design/method: We performed a retrospective observational study between 2015 and 2022. Patients with CD who had baseline and follow-up SES-CD scores after biological therapy initiation were included. The primary outcome was treatment failure, defined as the need for: (1) change of biological therapy for active disease (2) corticosteroid use (3) CD-related hospitalisation or (4) surgery. We compared rates of treatment failure with the degree of MH achieved. Patients were followed up until treatment failure or study end (August 2022). Results: 50 patients were included and followed up for median 39.9 (34.6-48.6) months. Baseline characteristics: 62% male, median age 36.4 (27.8-43.9) years, disease distribution (L1: 4, L2: 11, L3: 35, perianal: 18). The proportion of patients achieving STRIDE-II end-points were: SES-CD≤2-25 (50%) and >50% reduction in SES-CD-35 (70%). Failure to achieve SES-CD≤2 (HR 11.62; 95% CI 3.33 to 40.56, p=0.003) or >50% improvement in SES-CD (HR 30.30; 95% CI 6.93 to 132.40, p<0.0001) predicted treatment failure. Conclusion: Use of SES-CD is feasible in real-world clinical practice. Achieving an SES-CD≤2 or a greater than 50% reduction, as set out by STRIDE-II, is associated with reduced rates of overall treatment failure including CD-related surgery.

A retrospective cohort study: pre-operative oral enteral nutritional optimisation for Crohn's disease in a UK tertiary IBD centre.

BACKGROUND: Low-quality evidence suggests that pre-operative exclusive enteral nutrition (E/EN) can improve postoperative outcomes in patients with Crohn's disease (CD). It is not standard practice in most centres. AIMS: To test the hypothesis that pre-operative EN in patients undergoing ileal/ileocolonic surgery for CD is associated with improved postoperative outcome. METHODS: We performed a single centre retrospective observational study comparing surgical outcomes in patients receiving pre-operative EN (≥600 kcal/day for ≥2 weeks) with those who received no nutritional optimisation. Consecutive adult patients undergoing ileal/ileocolonic resection from 2008 to 2020 were included. The primary outcome was postoperative complications <30 days. Secondary outcomes included EN tolerance, specific surgical complications, unplanned stoma formation, length of stay, length of bowel resected, readmission and biochemical/anthropometric changes. RESULTS: 300 surgeries were included comprising 96 without nutritional optimisation and 204 optimised cases: oral EN n = 173, additional PN n = 31 (4 of whom had received nasogastric/nasojejunal EN). 142/204 (69.6%) tolerated EN. 125/204 (61.3%) initiated EN in clinic. Patients in the optimised cohort were younger at operation and diagnosis, with an increased frequency of penetrating disease and exposure to antibiotics or biologics, and were more likely to undergo laparoscopic surgery. The optimised cohort had favourable outcomes on multivariate analysis: all complications [OR 0.29; 0.15-0.57, p < 0.001], surgical complications [OR 0.41; 95% CI 0.20-0.87, p = 0.02], non-surgical complications [OR 0.24 95% CI 0.11-0.52, p < 0.001], infective complications [OR 0.32; 95% CI 0.16-0.66, p = 0.001]. CONCLUSIONS: Oral EN was reasonably well tolerated and associated with a reduction in 30-day postoperative complications. Randomised controlled trials are required to confirm these findings.

Depression, anxiety, and stress among inflammatory bowel disease patients during COVID-19: A UK cohort study.

BACKGROUND AND AIM: Patients with chronic diseases are believed to be at increased risk of mental health conditions during the COVID-19 pandemic. We aimed to assess the incidence of psychological morbidity in inflammatory bowel disease (IBD) patients during the COVID-19 pandemic, explore for association with risk of severe COVID-19 and other factors, and establish patients' interest in psychological support. METHODS: A survey including the Patient Health Questionnaire-9, General Anxiety Disorder-7, and Perceived Stress Scale tools for depression, anxiety, and stress was administered to IBD patients from a tertiary center in London, United Kingdom, in June 2020. RESULTS: Two hundred seventy-four patients responded to the survey (57% response rate), with 271 (99%) completing it. Moderate-severe depression was observed in 61 (22.5%), while 49 (18%) had moderate-severe anxiety; 39 (14%) had both diagnoses. Mean (SD) stress score was 16.2 (7.4). There was no association between degree of severe COVID-19 risk and psychological morbidity. Flare symptoms and fatigue were associated with worse psychological morbidity, while accessibility of information regarding COVID-19 risk and reducing that risk was protective for depression (odds ratio [OR] 0.56 [0.33-0.94], P = 0.03), anxiety (OR 0.62 [0.4-0.96], P = 0.03), and stress (standardized ß-coefficient -0.15 [-0.28 to -0.03], P = 0.02). Seventy-nine (30%) respondents were interested in receiving psychological support during the pandemic, while 200 (76%) expressed interest beyond the pandemic. CONCLUSIONS: Although depression, anxiety, and stress among IBD patients during the pandemic were common, their frequency was similar to pre-pandemic rates and recent general population levels. Ensuring easy access to personalized risk information with targeted psychological support may mitigate psychological burden as patients reintegrate into society and deal with future COVID-19 waves.

An observational study of switching infliximab biosimilar: no adverse impact on inflammatory bowel disease control or drug levels with first or second switch.

BACKGROUND: Biologics account for a significant cost in inflammatory bowel disease (IBD) management; however, switching from infliximab originator to its biosimilars has enabled cost saving without compromising disease control. The effects on IBD activity and infliximab trough levels of a second switch to another biosimilar are, however, uncertain. AIMS: To assess the effects on disease activity and infliximab trough levels associated with switching from infliximab biosimilar CT-P13 to another biosimilar SB2 and compare outcomes in those switching for the first and second time. METHODS: IBD patients on CT-P13, including some previously switched from originator, were prospectively followed during a switch to SB2. C-reactive protein (CRP), trough infliximab level and clinical disease activity indices were collected at baseline, Infusion 3 or 4 ('early' after switch), and 1 year. RESULTS: One hundred eighty-six patients (n = 99 second switch) on stable infliximab dosing underwent switching. Compared with baseline, there was no significant change in CRP, clinical disease activity scores or median trough infliximab level at the early time point among first-switch (baseline vs early: 5.7 vs 6.6 µg/mL, P = 0.05) and second-switch (4.3 vs 4.9 µg/mL, P = 0.07) patients nor at 1 year (median infliximab trough levels, baseline vs 1 year, in first-switch [5.7 vs 5.7 µg/mL, P = 0.37] and second-switch [4.3 vs 4.7 µg/mL, P = 0.06] patients). The proportion of patients in clinical remission did not significantly change at the early (92% vs 91% at baseline, P = 0.75) or 1 year (95% vs 91% at baseline, P = 0.16) time points. There was no significant difference in time to loss of response between patients switching for the first or second time (P = 0.69). CONCLUSIONS: Switching from one infliximab biosimilar to another had no adverse impact on infliximab trough levels, and clinical and biochemical disease activity, regardless of whether switching for the first or second time.

Interleukin 33 Triggers Early Eosinophil-Dependent Events Leading to Metaplasia in a Chronic Model of Gastritis-Prone Mice.

BACKGROUND & AIMS: Interleukin (IL)33/IL1F11 is an important mediator for the development of type 2 T-helper cell (Th2)-driven inflammatory disorders and has also been implicated in the pathogenesis of gastrointestinal (GI)-related cancers, including gastric carcinoma. We therefore sought to mechanistically determine IL33's potential role as a critical factor linking chronic inflammation and gastric carcinogenesis using gastritis-prone SAMP1/YitFc (SAMP) mice. METHODS: SAMP and (parental control) AKR mice were assessed for baseline gastritis and progression to metaplasia. Expression/localization of IL33 and its receptor, ST2/IL1R4, were characterized in corpus tissues, and activation and neutralization studies were both performed targeting the IL33/ST2 axis. Dissection of immune pathways leading to metaplasia was evaluated, including eosinophil depletion studies using anti-IL5/anti-CCR3 treatment. RESULTS: Progressive gastritis and, ultimately, intestinalized spasmolytic polypeptide-expressing metaplasia (SPEM) was detected in SAMP stomachs, which was absent in AKR but could be moderately induced with exogenous, recombinant IL33. Robust peripheral (bone marrow) expansion of eosinophils and local recruitment of both eosinophils and IL33-expressing M2 macrophages into corpus tissues were evident in SAMP. Interestingly, IL33 blockade did not affect bone marrow-derived expansion and local infiltration of eosinophils, but markedly decreased M2 macrophages and SPEM features, while eosinophil depletion caused a significant reduction in both local IL33-producing M2 macrophages and SPEM in SAMP. CONCLUSIONS: IL33 promotes metaplasia and the sequelae of eosinophil-dependent downstream infiltration of IL33-producing M2 macrophages leading to intestinalized SPEM in SAMP, suggesting that IL33 represents a critical link between chronic gastritis and intestinalizing metaplasia that may serve as a potential therapeutic target for preneoplastic conditions of the GI tract.

The effects of COVID-19 on IBD prescribing and service provision in a UK tertiary centre.

BACKGROUND: To quantify the effects of COVID-19 on our inflammatory bowel disease (IBD) unit, including service provision, prescribing practices and use of therapeutic drug monitoring (TDM). METHODS: We performed a single centre retrospective observational cohort study. Data was extracted from our IBD database, electronic patient records and radiology/endoscopy reporting systems between 16/3/20-17/4/20 and the corresponding period in 2019. RESULTS: A similar number of patients commenced biologic therapy before COVID-19 (n = 37) and during the pandemic (n = 36). Patients in the pre-COVID-19 cohort were older (median 36 vs 29 years, P = 0.009) with a longer median disease duration (9.3 vs 5.2 years, P = 0.02). During COVID-19 there was a nonsignificant increase in prescribing of vedolizumab (8/37, 22% vs 14/36, 39%, P = 0.13) and a higher proportion of patients were anti-TNF-naïve (3/17, 18% vs 18/24, 74%, P = 0.0004). There was a reduction in use of concomitant immunomodulators (22/29, 76% vs 4/34, 12%, P < 0.0001) and increased biologic use in thiopurine-naïve patients (3/37, 8% vs 15/36, 42%, P = 0.001). Use of TDM fell by 75% (240 vs 59 tests). Outpatient appointments fell by 68% and were conducted via telemedicine. MRI scanning, endoscopy, luminal surgery and inpatient numbers fell by 87%, 85%, 100% and 82% respectively. IBD Clinical Nurse Specialist and Pharmacist helpline contacts increased by 76% and 228% respectively. CONCLUSIONS: We observed prescribing differences during COVID-19, bypassing the initiation of immunomodulators and/or anti-TNF therapy in favour of vedolizumab with a reduction in immunomodulator prescribing. We also observed a rapid reorganisation of service provision, including a shift towards telemedicine and online solutions.

Therapeutic thresholds for golimumab serum concentrations during induction and maintenance therapy in ulcerative colitis: results from the GO-LEVEL study.

BACKGROUND: Significant associations between serum golimumab concentrations and favourable outcomes have been observed during both induction and maintenance therapy in ulcerative colitis (UC). However, data regarding optimal therapeutic serum golimumab concentration thresholds are limited. AIMS: To identify optimal serum golimumab concentration thresholds during induction and maintenance treatment with golimumab. METHODS: GO-LEVEL was an open label, phase IV study that included a prospective cohort of UC patients commencing golimumab, as well as a cross-sectional cohort receiving maintenance treatment. Patients commencing induction for active UC (defined as a simple clinical colitis activity index [SCCAI] >5 in addition to a raised faecal calprotectin [FC] >59µg/g or, raised C-reactive protein [CRP] [>5mg/L] or, Mayo endoscopic disease activity 2 or 3) were evaluated at weeks 6, 10 and 14. Patients receiving maintenance therapy were recruited either at the point of flare or during remission. Combined clinical-biochemical remission was defined as SCCAI ≤2 and FC <250µg/g. Serum golimumab concentrations were measured using a commercially available ELISA (LISATRACKER, Theradiag). RESULTS: Thirty-nine patients were included in the induction cohort, of whom 15 (38%) achieved combined clinical-biochemical remission at week 6. The median serum golimumab concentration of those in combined clinical-biochemical remission was significantly higher than those who were not (5.0 vs 3.1 µg/mL, respectively, P = 0.03). Receiver operating characteristic (ROC) curve analysis demonstrated 3.8 µg/mL as the optimal threshold (sensitivity 0.71, specificity 0.65, area under curve [AUC] 0.72, positive predictive value [PPV] 0.59 and negative predictive value [NPV] 0.79). Sixty-three patients were included in the maintenance cohort; 31 (49%) were in combined remission, 32 (51%) were not. The median serum golimumab concentration of those in combined remission was significantly higher (2.9 vs 2.1 µg/mL, respectively, P = 0.01). ROC curve analysis demonstrated 2.4 µg/mL as the optimal threshold (sensitivity 0.68, specificity 0.66, AUC 0.68, PPV 0.65 and NPV 0.66). CONCLUSIONS: GO-LEVEL (NCT03124121) offers further evidence regarding golimumab's exposure-response relationship. Clinicians may consider using therapeutic drug monitoring to optimise golimumab dosing aiming to achieve our suggested therapeutic thresholds of 3.8 µg/mL at week 6 and 2.4 µg/mL during maintenance.

Effectiveness of vedolizumab dose intensification to achieve inflammatory bowel disease control in cases of suboptimal response.

BACKGROUND: Despite the proven efficacy of vedolizumab (VDZ) for ulcerative colitis (UC) and Crohn's disease (CD), suboptimal response is commonly encountered. However, data regarding the effectiveness of dose intensification (by interval shortening) to achieve response are limited. OBJECTIVES: We evaluated the effectiveness of dose intensification at achieving response in patients with a previously suboptimal response to VDZ. Additionally, we aimed to identify predictors of response to this strategy. METHODS: We performed a retrospective cohort study of patients who underwent VDZ dose intensification for suboptimal response. Clinical disease activity was evaluated at the point of dose intensification (baseline) and at weeks 12 and 24. Response was defined as Harvey-Bradshaw Index (HBI) or Simple Clinical Colitis Activity Index (SCCAI) reduction of ≥3, and remission as HBI <5 or SCCAI <3. RESULTS: A total of 36 patients received dose intensification to 4-weekly infusions: 18 CD, 14 UC and 4 inflammatory bowel disease-unclassified (analysed in the UC group). Median SCCAI scores fell from 6 (range 0-11) at baseline to 4 (0-6, p=0.008) at week 24, while HBI scores did not change significantly (4 (0-27) and 3 (0-8), p=0.092). Overall median C reactive protein (CRP) fell from 6 mg/L (1-23) to 2 mg/L (1-17, p=0.011). Of 20 patients with clinically active disease at baseline, 10 (50%) responded, of whom 4 (20%) achieved remission at week 24. Univariate analysis demonstrated low baseline CRP (p=0.045) and response at week 12 (0.020) were associated with week 24 response. CONCLUSIONS: Our findings demonstrate VDZ dose intensification to be effective at achieving clinical response in half of patients. Low baseline CRP and response at week 12 are potential predictors of week 24 response.

Real-world Effectiveness of Tofacitinib for Moderate to Severe Ulcerative Colitis: A Multicentre UK Experience.

BACKGROUND: Tofacitinib is a partially selective Janus kinase inhibitor approved for the treatment of refractory moderate to severe ulcerative colitis [UC]. We sought to define the effectiveness and adverse effects of tofacitinib in a real-world cohort. METHODS: We conducted a retrospective observational cohort study of 134 patients with UC [64% male; median age 37 years [range 16-81]; 83% of patients had previously received at least one biologic] treated with tofacitinib from October 2018 to October 2019 in four UK centres. Disease activity was assessed using the Simple Clinical Colitis Activity Index [SCCAI] or partial Mayo score [PMS], depending on study site. Response and remission were defined as a reduction in SCCAI or PMS of ≥3and SCCAI ≤2 or a PMS ≤1, respectively. RESULTS: Overall, 74% (88/119; 95 confidence interval [CI] 65-81%] patients responded to tofacitinib at Week 8 and steroid-free remission was observed in 44% [47/108; 95% CI 3453%] patients at Week 26. Primary non-response was independently associated with younger age [p = 0.014] and higher C-reactive protein [CRP] levels at baseline [p = 0.004]. Only 23% [3/13] of patients who continued tofacitinib in the setting of primary non-response were in steroid-free remission at Week 26. Prior biologic exposure did not influence response or remission rates. Dose escalation, however, recaptured response in approximately half of patients who had lost response. Dyslipidaemia was observed in 20% [27/134; 95% CI 1428%] of patients, but adverse events necessitating drug withdrawal were uncommon and no venous thromboembolic events occurred. CONCLUSIONS: In this multicentre real-world cohort, tofacitinib was well tolerated and clinically effective in a treatment-refractory UC population.

Validation and Investigation of the Operating Characteristics of the Ulcerative Colitis Endoscopic Index of Severity.

BACKGROUND: The Ulcerative Colitis Endoscopic Index of Severity (UCEIS) is a novel instrument to evaluate endoscopic disease activity. It has been demonstrated to outperform the more widely used Mayo endoscopic score (MES) in predicting long-term prognosis, including the need for colectomy. Despite its potential benefits, many clinicians still prefer to use MES because its operating characteristics are better defined and its grades are more readily applicable to clinical decision-making. The aims of our study were to quantify the UCEIS cutoff most closely associated with the need for treatment escalation and to perform a validation exercise using MES and clinical, biochemical, and histological measures of disease activity. METHODS: Endoscopies performed in UC patients between November 2016 and January 2018 were retrospectively reviewed. Agreement between the UCEIS and MES was quantified using Kappa (κ) statistics. A UCEIS cutoff for treatment escalation was calculated using chi-square, receiver operating characteristic curve, and area under the curve (AUC) analyses. The Pearson correlation coefficient was used to compare linear relationships between UCEIS and clinical (Simple Clinical Colitis Activity Index [SCCAI]), biochemical (C-reactive protein [CRP]), and histological (Nancy Histological Index [NHI]) activity. RESULTS: Two hundred one (56%) procedures documented both UCEIS and MES, demonstrating substantial agreement (κ = 0.713; P < 0.001). Treatment was escalated after 199 (56%) procedures. Receiver operating characteristic curve analysis of need for treatment escalation showed the highest sensitivity and specificity for UCEIS ≥4 (0.80 and 0.93, respectively; AUC, 0.93). Of 170 patients with a UCEIS ≥4, treatment was escalated in 159 (94%), but not for 11 (6%). Of 185 patients with a UCEIS ≤3, 40 (22%) were escalated, whereas 145 (78%) were not (P < 0.001). UCEIS correlated strongly with NHI (0.723; P < 0.001), moderately with SCCAI (0.671; P < 0.001), and weakly with CRP (0.279; P < 0.001). CONCLUSIONS: A UCEIS ≥4 was significantly associated with treatment escalation. This cutoff could therefore be used to support clinical decision-making based on endoscopic findings. Strong and moderate correlations were found between UCEIS and histological and clinical disease activity, respectively, whereas a weak correlation was found with CRP.10.1093/ibd/izy325_Video_1 izy325.video1 5849933952001.

Current Practices in Ileal Pouch Surveillance for Patients With Ulcerative Colitis: A Multinational, Retrospective Cohort Study.

BACKGROUND AND AIMS: There are no universally accepted guidelines regarding surveillance of ulcerative colitis [UC] patients after restorative proctocolectomy and ileal pouch-anal anastomosis [IPAA]. There also exists a lack of validated quality assurance standards for performing pouchoscopy. To better understand IPAA surveillance practices in the face of this clinical equipoise, we carried out a retrospective cohort study at five inflammatory bowel disease [IBD] referral centres. METHODS: Records of patients who underwent IPAA for UC or IBD unclassified [IBDU] were reviewed, and patients with <1-year follow-up after restoration of intestinal continuity were excluded. Criteria for determining the risk of pouch dysplasia formation were collected as well as the use of pouchoscopy, biopsies, and completeness of reports. RESULTS: We included 272 patients. Median duration of pouch follow-up was 10.5 [3.3-23.6] years; 95/272 [35%] had never undergone pouchoscopy for any indication; 191/272 [70%] had never undergone pouchoscopy with surveillance as the specific indication; and 3/26 [12%] high-risk patients had never undergone pouchoscopy. Two cases of adenocarcinoma were identified, occurring in the rectal cuff of low-risk patients. Patients under the care of surgeons appeared more likely to undergo surveillance, but rates of incomplete reporting were higher among surgeons [78%] than gastroenterologists [54%, p = 0.002]. CONCLUSIONS: We observed wide variation in surveillance of UC/IBDU-IPAA patients. In addition, the rate of neoplasia formation among 'low-risk' patients was higher than may have been expected. We therefore concur with previous recommendations that pouchoscopy be performed at 1 year postoperatively, to refine risk-stratification based on clinical factors alone. Reports should document findings in all regions of the pouch and biopsies should be taken.

In vitro and in vivo modeling of lipid bioaccessibility and digestion from almond muffins: The importance of the cell-wall barrier mechanism.

This study compares in vitro and in vivo models of lipid digestion from almond particles within a complex food matrix (muffins) investigating whether the cell-wall barrier regulates the bioaccessibility of nutrients within this matrix. Muffins containing small (AF) or large (AP) particles of almond were digested in triplicate using an in vitro dynamic gastric model (DGM, 1 h) followed by a static duodenal digestion (8 h). AF muffins had 97.1 ± 1.7% of their lipid digested, whereas AP muffins had 57.6 ± 1.1% digested. In vivo digestion of these muffins by an ileostomy volunteer (0-10 h) gave similar results with 96.5% and 56.5% lipid digested, respectively. The AF muffins produced a higher postprandial triacylglycerol iAUC response (by 61%) than the AP muffins. Microstructural analysis showed that some lipid remained encapsulated within the plant tissue throughout digestion. The cell-wall barrier mechanism is the main factor in regulating lipid bioaccessibility from almond particles.

Outcomes following Serial Intragastric Balloon Therapy for Obesity and Nonalcoholic Fatty Liver Disease in a Single Centre.

Background: The incidence of nonalcoholic fatty liver disease (NAFLD) continues to parallel the rise in obesity rates. Endobariatric devices such as the intragastric balloon (IGB) may provide an alternative treatment option. Methods: Outcomes following IGB treatment in 135 patients with obesity and NAFLD (mean baseline weight 117.9 kg; BMI 41.7 kg/m2; HOMA-IR 3.6) were retrospectively examined. Clinical, anthropometric, and biochemical changes were analysed at six months and after consecutive treatment with two and three serial IGBs. Results: After six months, significant changes were seen with weight and BMI (mean reductions of 11.3 kg and 4.1 kg/m2, resp., p < 0.01 for both). Significant improvements were also seen with ALT, GGT, and HOMA-IR, with all changes corresponding with weight loss. Forty-eight patients received two IGBs, and 20 were treated with three serial IGBs. The greatest amount of total weight loss was observed after the first 6 months (mean weight lost 7.4 kg, versus 3.6 kg and 1.9 kg with two and three IGBs, resp.). Conclusions: IGB therapy is an effective, alternative nonsurgical means for weight loss in the management of obesity and NAFLD over the short term, with greatest outcomes observed after six months. Improvements in insulin resistance and hepatic transaminases correlated with weight change.

Short Communication: Lack of Effect of Maraviroc Intensification on Blood and Gut Reservoir.

We show that intensification of treatment with maraviroc in patients chronically infected with HIV-1 receiving successful long-term antiretroviral therapy was not associated with improvements in HIV-related morbidity, HIV reservoir, microbial translocation, immune activation, or immune exhaustion in either gut or peripheral blood. The measurement of reservoir in both gut and blood longitudinally contributes to a paucity of data in the area.

Hepatic rhythmicity of endoplasmic reticulum stress is disrupted in perinatal and adult mice models of high-fat diet-induced obesity.

We investigated the regulation of hepatic ER stress in healthy liver and adult or perinatally programmed diet-induced non-alcoholic fatty liver disease (NAFLD). Female mice were fed either obesogenic or control diet before mating, during pregnancy and lactation. Post-weaning, offspring from each maternal group were divided into either obesogenic or control diet. At six months, offspring were sacrificed at 4-h intervals over 24 h. Offspring fed obesogenic diets developed NAFLD phenotype, and the combination of maternal and offspring obesogenic diets exacerbated this phenotype. UPR signalling pathways (IREα, PERK, ATF6) and their downstream regulators showed different basal rhythmicity, which was modified in offspring exposed to obesogenic diet and maternal programming. The double obesogenic hit increased liver apoptosis measured by TUNEL staining, active caspase-3 and phospho-JNK and GRP78 promoter methylation levels. This study demonstrates that hepatic UPR is rhythmically activated. The combination of maternal obesity (MO) and obesogenic diets in offspring triggered altered UPR rhythmicity, DNA methylation and cellular apoptosis.

Mechanisms and models for intestinal fibrosis in IBD.

Intestinal fibrosis is a common outcome in IBD leading to significant morbidity that, to date, has no effective medical treatment. Current knowledge regarding potential mechanism(s) of intestinal fibrogenesis and stricture formation is limited, due in large part to the lack of relevant animal models. Although conventional models possess aspects that are advantageous to study specific mechanisms involved in gut fibrosis, most lack the features of a spontaneously occurring process leading to the formation of intestinal fibrotic lesions following mucosal inflammatory events and the ability to investigate the natural course of disease over time. This review aims to discuss established and novel animal models of gut fibrosis, particularly focusing on the advantages and disadvantages of each model system and the insights they bring to our understanding of the mechanisms of fibrogenesis. In fact, recent enhancements to existing models and the expansion of novel animal models of gut fibrosis is opening up multiple avenues for investigation which should stimulate progress in our mechanistic understanding of intestinal fibrogenesis and facilitate the development of effective pharmacotherapy in an area of significant unmet need.

Central role of IL-17/Th17 immune responses and the gut microbiota in the pathogenesis of intestinal fibrosis.

PURPOSE OF REVIEW: Intestinal fibrosis is a serious, yet common, outcome in patients with inflammatory bowel disease (IBD). Despite advances in developing novel treatment modalities to control chronic gut inflammation characteristic of IBD, no effective antifibrotic therapies exist to date. As such, a deeper understanding of the molecular mechanisms underlying intestinal fibrosis and the availability of relevant animal models are critical to move this area of investigation forward. RECENT FINDINGS: Emerging concepts in the pathogenesis of intestinal fibrosis include the central role of interleukin (IL)-17 and Th17 immune responses, although their precise contribution to chronic inflammation and IBD remains controversial. Other novel mediators of intestinal fibrosis, such as tumor necrosis factor-like ligand 1A and components of the renin-angiotensin system, support the importance of IL-17. Additionally, recent studies utilizing novel mouse models highlight the significance of the gut microbiota and link components of bacterial sensing, including nucleotide-binding oligomerization domain-containing protein 2, to IL-17/Th17 immune responses in the development of inflammation-associated intestinal fibrosis. SUMMARY: Recent progress in identifying key mediators, novel animal models, and important mechanistic pathways in the pathogenesis of intestinal fibrosis holds promise for the development of effective antifibrotics in an area of significant, unmet clinical need.